Search results for: Maria Soledad Vicente
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1110

Search results for: Maria Soledad Vicente

60 A Patient-Centered Approach to Clinical Trial Development: Real-World Evidence from a Canadian Medical Cannabis Clinic

Authors: Lucile Rapin, Cynthia El Hage, Rihab Gamaoun, Maria-Fernanda Arboleda, Erin Prosk

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Introduction: Sante Cannabis (SC), a Canadian group of clinics dedicated to medical cannabis, based in Montreal and in the province of Quebec, has served more than 8000 patients seeking cannabis-based treatment over the past five years. As randomized clinical trials with natural medical cannabis are scarce, real-world evidence offers the opportunity to fill research gaps between scientific evidence and clinical practice. Data on the use of medical cannabis products from SC patients were prospectively collected, leading to a large real-world database on the use of medical cannabis. The aim of this study was to report information on the profiles of both patients and prescribed medical cannabis products at SC clinics, and to assess the safety of medical cannabis among Canadian patients. Methods: This is an observational retrospective study of 1342 adult patients who were authorized with medical cannabis products between October 2017 and September 2019. Information regarding demographic characteristics, therapeutic indications for medical cannabis use, patterns in dosing and dosage form of medical cannabis and adverse effects over one-year follow-up (initial and 4 follow-up (FUP) visits) were collected. Results: 59% of SC patients were female, with a mean age of 56.7 (SD= 15.6, range= (19-97)). Cannabis products were authorized mainly for patients with a diagnosis of chronic pain (68.8% of patients), cancer (6.7%), neurological disorders (5.6%), and mood disorders (5.4 %). At initial visit, a large majority (70%) of patients were authorized exclusively medical cannabis products, 27% were authorized a combination of pharmaceutical cannabinoids and medical cannabis and 3% were prescribed only pharmaceutical cannabinoids. This pattern was recurrent over the one-year follow-up. Overall, oil was the preferred formulation (average over visits 72.5%) followed by a combination of oil and dry (average 19%), other routes of administration accounted for less than 4%. Patients were predominantly prescribed products with a balanced THC:CBD ratio (59%-75% across visits). 28% of patients reported at least one adverse effect (AE) at the 3-month follow-up visit and 12% at the six-month FUP visit. 84.8% of total AEs were mild and transient. No serious AE was reported. Overall, the most common side effects reported were dizziness (11.95% of total AEs), drowsiness (11.4%), dry mouth (5.5%), nausea (4.8%), headaches (4.6%), cough (4.4%), anxiety (4.1%) and euphoria (3.5%). Other adverse effects accounted for less than 3% of total AE. Conclusion: Our results confirm that the primary area of clinical use for medical cannabis is in pain management. Patients in this cohort are largely utilizing plant-based cannabis oil products with a balanced ratio of THC:CBD. Reported adverse effects were mild and included dizziness and drowsiness. This real-world data confirms the tolerable safety profile of medical cannabis and suggests medical indications not yet validated in controlled clinical trials. Such data offers an important opportunity for the investigation of the long-term effects of cannabinoid exposure in real-life conditions. Real-world evidence can be used to direct clinical trial research efforts on specific indications and dosing patterns for product development.

Keywords: medical cannabis, safety, real-world data, Canada

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59 The Evaluation of Child Maltreatment Severity and the Decision-Making Processes in the Child Protection System

Authors: Maria M. Calheiros, Carla Silva, Eunice Magalhães

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Professionals working in child protection services (CPS) need to have common and clear criteria to identify cases of maltreatment and to differentiate levels of severity in order to determine when CPS intervention is required, its nature and urgency, and, in most countries, the service that will be in charge of the case (community or specialized CPS). Actually, decision-making process is complex in CPS, and, for that reason, such criteria are particularly important for who significantly contribute to that decision-making in child maltreatment cases. The main objective of this presentation is to describe the Maltreatment Severity Assessment Questionnaire (MSQ), specifically designed to be used by professionals in the CPS, which adopts a multidimensional approach and uses a scale of severity within subtypes. Specifically, we aim to provide evidence of validity and reliability of this tool, in order to improve the quality and validity of assessment processes and, consequently, the decision making in CPS. The total sample was composed of 1000 children and/or adolescents (51.1% boys), aged between 0 and 18 years old (M = 9.47; DP = 4.51). All the participants were referred to official institutions of the children and youth protective system. Children and adolescents maltreatment (abuse, neglect experiences and sexual abuse) were assessed with 21 items of the Maltreatment Severity Questionnaire (MSQ), by professionals of CPS. Each item (sub-type) was composed of four descriptors of increasing severity. Professionals rated the level of severity, using a 4-point scale (1= minimally severe; 2= moderately severe; 3= highly severe; 4= extremely severe). The construct validity of the Maltreatment Severity Questionnaire was assessed with a holdout method, performing an Exploratory Factor Analysis (EFA) followed by a Confirmatory Factor Analysis (CFA). The final solution comprised 18 items organized in three factors 47.3% of variance explained. ‘Physical neglect’ (eight items) was defined by parental omissions concerning the insurance and monitoring of the child’s physical well-being and health, namely in terms of clothing, hygiene, housing conditions and contextual environmental security. ‘Physical and Psychological Abuse’ (four items) described abusive physical and psychological actions, namely, coercive/punitive disciplinary methods, physically violent methods or verbal interactions that offend and denigrate the child, with the potential to disrupt psychological attributes (e.g., self-esteem). ‘Psychological neglect’ (six items) involved omissions related to children emotional development, mental health monitoring, school attendance, development needs, as well as inappropriate relationship patterns with attachment figures. Results indicated a good reliability of all the factors. The assessment of child maltreatment cases with MSQ could have a set of practical and research implications: a) It is a valid and reliable multidimensional instrument to measure child maltreatment, b) It is an instrument integrating the co-occurrence of various types of maltreatment and a within-subtypes scale of severity; c) Specifically designed for professionals, it may assist them in decision-making processes; d) More than using case file reports to evaluate maltreatment experiences, researchers could guide more appropriately their research about determinants and consequences of maltreatment.

Keywords: assessment, maltreatment, children and youth, decision-making

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58 Re-Creating Women of the Past in Historical Series on Mexican Television: The Work of Patricia Arriaga Jordan

Authors: Maria De Los Angeles Rodriguez Cadena

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This paper discusses how the fictional versions of women of the past contribute to advance today’s ideas of social justice, personal freedom and emancipation as well as to highlight the creative challenge of constructing people and events on fictional narratives on television that incorporate multiple and simultaneous layers of meaning and complexity. This project builds on existing scholarship on audiovisual texts by exploring an influential but under-studied director. In two Mexican television series, Patricia Arriaga Jordan, an award-winning television producer, scriptwriter and director, constructs the life of two outstanding women that have played an influential role in national history and captured Mexican’s popular imagination for generations: Sor Juana Inés de la Cruz, and Malinche. Malinche (2018) tells the story of an extraordinary indigenous woman, Malintzin, during the Spanish Conquest (1511-1550) that is considered to have played a key role in the fall of the Aztec empire by acting as translator, negotiator and cultural mediator for the Spanish conquerors. Juana Ines (2016) portrays Sor Juana, a poet, essayist, playwright, theologian, philosopher, nun, of XVII century colonial Mexico, one of the brightest minds of her time, and now recognized as the first feminist of the Americas who wrote on the rights of women to an education, religious authority and feminist advocacy. Both series, as fictional narratives that recreate defining historical periods, specific events and relevant characters in the History of Mexico can be read as an example of what is called texts of cultural memory. A cultural memory text is a narrative that bonds the concepts of history, identity and belonging, and that is realized and disseminated through symbolic systems such as written documents, visual images, and dramatic representation. Cultural memory, through its narratives of historical fiction, emphasizes memory processes (historiography) and its implications and artifacts (cultural memory) mainly through the medial frameworks of remembering, which are the medial process by which memories (narratives, documents) participate in public knowledge and become collective memory. Historical fiction on television not only creates a portrayal of the past related to the real lives of protagonists, but it also significantly contributes to understand the past as an ever-evolving entity that highlights both, the necessary connection with the present as part of a developing sense of collective identity and belonging, as well as the relevance of the medium in which the past is represented and that ultimately supports the process of historical awareness. Through the emblematic recreation of national heroines and historical events in the unique context of historical drama on television, those texts constitute a venue where concepts of the past and the traditionally established ideas about history and heroines are highlighted, questioned and transformed.

Keywords: cultural memory, historical fiction, Mexico, television, women directors

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57 Automatic Identification of Pectoral Muscle

Authors: Ana L. M. Pavan, Guilherme Giacomini, Allan F. F. Alves, Marcela De Oliveira, Fernando A. B. Neto, Maria E. D. Rosa, Andre P. Trindade, Diana R. De Pina

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Mammography is a worldwide image modality used to diagnose breast cancer, even in asymptomatic women. Due to its large availability, mammograms can be used to measure breast density and to predict cancer development. Women with increased mammographic density have a four- to sixfold increase in their risk of developing breast cancer. Therefore, studies have been made to accurately quantify mammographic breast density. In clinical routine, radiologists perform image evaluations through BIRADS (Breast Imaging Reporting and Data System) assessment. However, this method has inter and intraindividual variability. An automatic objective method to measure breast density could relieve radiologist’s workload by providing a first aid opinion. However, pectoral muscle is a high density tissue, with similar characteristics of fibroglandular tissues. It is consequently hard to automatically quantify mammographic breast density. Therefore, a pre-processing is needed to segment the pectoral muscle which may erroneously be quantified as fibroglandular tissue. The aim of this work was to develop an automatic algorithm to segment and extract pectoral muscle in digital mammograms. The database consisted of thirty medio-lateral oblique incidence digital mammography from São Paulo Medical School. This study was developed with ethical approval from the authors’ institutions and national review panels under protocol number 3720-2010. An algorithm was developed, in Matlab® platform, for the pre-processing of images. The algorithm uses image processing tools to automatically segment and extract the pectoral muscle of mammograms. Firstly, it was applied thresholding technique to remove non-biological information from image. Then, the Hough transform is applied, to find the limit of the pectoral muscle, followed by active contour method. Seed of active contour is applied in the limit of pectoral muscle found by Hough transform. An experienced radiologist also manually performed the pectoral muscle segmentation. Both methods, manual and automatic, were compared using the Jaccard index and Bland-Altman statistics. The comparison between manual and the developed automatic method presented a Jaccard similarity coefficient greater than 90% for all analyzed images, showing the efficiency and accuracy of segmentation of the proposed method. The Bland-Altman statistics compared both methods in relation to area (mm²) of segmented pectoral muscle. The statistic showed data within the 95% confidence interval, enhancing the accuracy of segmentation compared to the manual method. Thus, the method proved to be accurate and robust, segmenting rapidly and freely from intra and inter-observer variability. It is concluded that the proposed method may be used reliably to segment pectoral muscle in digital mammography in clinical routine. The segmentation of the pectoral muscle is very important for further quantifications of fibroglandular tissue volume present in the breast.

Keywords: active contour, fibroglandular tissue, hough transform, pectoral muscle

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56 An Epidemiological Study on Cutaneous Melanoma, Basocellular and Epidermoid Carcinomas Diagnosed in a Sunny City in Southeast Brazil in a Five-Year Period

Authors: Carolina L. Cerdeira, Julia V. F. Cortes, Maria E. V. Amarante, Gersika B. Santos

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Skin cancer is the most common cancer in several parts of the world; in a tropical country like Brazil, the situation isn’t different. The Brazilian population is exposed to high levels of solar radiation, increasing the risk of developing cutaneous carcinoma. Aimed at encouraging prevention measures and the early diagnosis of these tumors, a study was carried out that analyzed data on cutaneous melanomas, basal cell, and epidermoid carcinomas, using as primary data source the medical records of 161 patients registered in one pathology service, which performs skin biopsies in a city of Minas Gerais, Brazil. All patients diagnosed with skin cancer at this service from January 2015 to December 2019 were included. The incidence of skin carcinoma cases was correlated with the identification of histological type, sex, age group, and topographic location. Correlation between variables was verified by Fisher's exact test at a nominal significance level of 5%, with statistical analysis performed by R® software. A significant association was observed between age group and type of cancer (p=0.0085); age group and sex (0.0298); and type of cancer and body region affected (p < 0.01). Those 161 cases analyzed comprised 93 basal cell carcinomas, 66 epidermoid carcinomas, and only two cutaneous melanomas. In the group aged 19 to 30 years, the epidermoid form was most prevalent; from 31 to 45 and from 46 to 59 years, the basal cell prevailed; in 60-year-olds or over, both types had higher frequencies. Associating age group and sex, in groups aged 18 to 30 and 46 to 59 years, women were most affected. In the 31-to 45-year-old group, men predominated. There was a gender balance in the age group 60-year-olds or over. As for topography, there was a high prevalence in the head and neck, followed by upper limbs. Relating histological type and topography, there was a prevalence of basal cell and epidermoid carcinomas in the head and neck. In the chest, the basal cell form was most prevalent; in upper limbs, the epidermoid form prevailed. Cutaneous melanoma affected only the chest and upper limbs. About 82% of patients 60-year-olds or over had head and neck cancer; from 46 to 59 and 60-year-olds or over, the head and neck region and upper limbs were predominantly affected; the distribution was balanced in the 31-to 45-year-old group. In conclusion, basal cell carcinoma was predominant, whereas cutaneous melanoma was the rarest among the types analyzed. Patients 60-year-olds or over were most affected, showing gender balance. In young adults, there was a prevalence of the epidermoid form; in middle-aged patients, basal cell carcinoma was predominant; in the elderly, both forms presented with higher frequencies. There was a higher incidence of head and neck cancers, followed by malignancies affecting the upper limbs. The epidermoid type manifested significantly in the upper limbs. Body regions such as the thorax and lower limbs were less affected, which is justified by the lower exposure of these areas to incident solar radiation.

Keywords: basal cell carcinoma, cutaneous melanoma, skin cancer, squamous cell carcinoma, topographic location

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55 MEIOSIS: Museum Specimens Shed Light in Biodiversity Shrinkage

Authors: Zografou Konstantina, Anagnostellis Konstantinos, Brokaki Marina, Kaltsouni Eleftheria, Dimaki Maria, Kati Vassiliki

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Body size is crucial to ecology, influencing everything from individual reproductive success to the dynamics of communities and ecosystems. Understanding how temperature affects variations in body size is vital for both theoretical and practical purposes, as changes in size can modify trophic interactions by altering predator-prey size ratios and changing the distribution and transfer of biomass, which ultimately impacts food web stability and ecosystem functioning. Notably, a decrease in body size is frequently mentioned as the third "universal" response to climate warming, alongside shifts in distribution and changes in phenology. This trend is backed by ecological theories like the temperature-size rule (TSR) and Bergmann's rule, which have been observed in numerous species, indicating that many species are likely to shrink in size as temperatures rise. However, the thermal responses related to body size are still contradictory, and further exploration is needed. To tackle this challenge, we developed the MEIOSIS project, aimed at providing valuable insights into the relationship between the body size of species, species’ traits, environmental factors, and their response to climate change. We combined a digitized collection of butterflies from the Swiss Federal Institute of Technology in Zürich with our newly digitized butterfly collection from Goulandris Natural History Museum in Greece to analyse trends in time. For a total of 23868 images, the length of the right forewing was measured using ImageJ software. Each forewing was measured from the point at which the wing meets the thorax to the apex of the wing. The forewing length of museum specimens has been shown to have a strong correlation with wing surface area and has been utilized in prior studies as a proxy for overall body size. Temperature data corresponding to the years of collection were also incorporated into the datasets. A second dataset was generated when a custom computer vision tool was implemented for the automated morphological measuring of samples for the digitized collection in Zürich. Using the second dataset, we corrected manual measurements with ImageJ, and a final dataset containing 31922 samples was used for analysis. Setting time as a smoother variable, species identity as a random factor, and the length of right-wing size (a proxy for body size) as the response variable, we ran a global model for a maximum period of 110 years (1900 – 2010). Then, we investigated functional variability between different terrestrial biomes in a second model. Both models confirmed our initial hypothesis and resulted in a decreasing trend in body size over the years. We expect that this first output can be provided as basic data for the next challenge, i.e., to identify the ecological traits that influence species' temperature-size responses, enabling us to predict the direction and intensity of a species' reaction to rising temperatures more accurately.

Keywords: butterflies, shrinking body size, museum specimens, climate change

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54 Cross-Sectional Associations between Deprivation Status and Physical Activity, Dietary Behaviours, Health-Related Variables, and Health-Related Quality of Life among Children Aged 9-11 Years

Authors: Maria Cardova

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Aim and objectives: The purpose of this studywas to explore to what extent the deprivation statusinfluenced children’s physical activity, dietary behaviour, and health outcomes such as weight status. Background: The United Kingdom’s childhood obesity rates are currently ranked among the highest in Europe. North West England deals with highest rates of childhood obesity. Data from the UK Millennium Cohort Study suggested a deprivation gradient to childhood obesity in England, with obesity rates being the highest in the most deprived areas. Traditionally, it has been individual conception of health, but the contemporary stance is that health behaviours affecting obesity are influenced by a broad range of factors operating at multiple levels. According to socio-ecological model of health behaviour, differences in obesity rates and health outcomes are likely explained by differences in lifestyle behaviours including physical activity and diet behaviours. However, higher rates of obesity among deprived children are not due to physical inactivity, in fact, most socially disadvantaged children are the most physically active. Poor diet including high consumption of fast food and sugar-sweetened beverages and low consumption of fruit and vegetables was found to be the most prevalent among adolescents living in poverty. Methods: This study adopted quantitative approach. It consisted of combination of basic demographic data, anthropometry, and questionnaires. Children (N = 165, mean age = 10.04 years; 53.33% female; 46.66% male) completed survey packs during school day including KIDSCREEN, Youth Activity Profile, Beverage and Snack Questionnaire, and Child Body Image Scale questionnaires as well as had anthropometric measurements taken including Body mass index, waist circumference, weight, and height. Children’s deprivation status was based on the English Indices of Multiple Deprivation scores of the school they attended. Results: Children from more deprived areas had higher weight status, waist circumference. Deprivation status had also effect on some dimensions of the KIDSCREEN questionnaire, such as that those from more deprived areas felt less socially accepted and bullied by their peers, had worse feelings about themselves such as body image, and more difficulty with school and learning. Children from more deprived areas reported higher rates of physical activity and also differences in snack and fruit and vegetable intake than their more affluent peers. Conclusion: Results demonstrated that, children living in the most-deprived areas appear to be at greater risk of unfavourable health-related variables and behaviours and are exposed to home and neighbourhood environments that are less conducive to health-promoting behaviours compared to their peers from less deprived areas. These findings indicate that children living in highly deprived areas represent an important group for future interventions designed to promote health-behaviours that would impact on the quality of life of the child and other health variables such as weight status.

Keywords: children, dietary behaviour, health, obesity, physical Activity, weight Status

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53 Impact of the COVID-19 Pandemic and Social Isolation on the Clients’ Experiences in Counselling and their Access to Services: Perspectives of Violence Against Women Program Staff - A Qualitative Study

Authors: Habiba Nahzat, Karen Crow, Lisa Manuel, Maria Huijbregts

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Background and Rationale: The World Health Organization (WHO) declared COVID-19 a pandemic on March 11, 2020. Shortly after, the Ontario provincial and Toronto municipal governments also released multiple directives that led to the mass closure of businesses both in the public and private sectors. Recent research has identified connections between Intimate Partner Violence (IPV) and COVID-19 related stressors - especially because of lockdown and social isolation measures. Psychological impacts of lengthy seclusion coupled with disconnection from extended family and diminished support services can take a toll on families at risk and may increase mental health issues and the prevalence of IPV. Research Question: Thus, the purpose of the study was to understand the perspective of the Violence Against Women (VAW) program staff on the impact of the COVID-19 pandemic; we especially wanted to understand staff views of restrictions on clients’ counseling experiences and the ability to access services in general. The study also aimed to examine VAW program staff experiences regarding remote work and explore how the pandemic restriction measures affected the ability of their program operations to support their clients and each other. Method: A cross-sectional, descriptive qualitative study was conducted with a purposive sample of 9 VAW program staff – eight VAW counselors and one VAW manager. Prior to data collection, program staff collaborated in the development of the study purpose, interview questions and methodology. Ethics approval was obtained from the sponsoring organization’s Research Ethics Board. In-depth individual interviews were conducted with study participants using a semi-structured interview questionnaire. Brief demographic information was also collected prior to the interview. Descriptive statistics were used to analyze quantitative data and qualitative data was analyzed by thematic content analysis. Results: Findings from this study indicate that the COVID-19 pandemic restrictions had an adverse impact on clients seeking VAW services based on VAW staff perspectives. Program staff reported a perceived increase in abuse among women, especially in emotional and financial abuse and experiences of isolation and trauma. Findings further highlight the challenges women experienced when trying to access services in general as well as counseling and legal services. This was perceived to be more prominent among newcomers and marginalized women. The study also revealed client and staff challenges when participating in virtual counseling, their innovations and clients’ creativity in accessing needed counseling and how staff over time adapted to providing virtual support during the pandemic. Conclusion and Next Steps: This study builds upon existing evidence on the impact of COVID-19 restrictions on VAW and may inform future research to better understand the association between the COVID-19 pandemic restrictions and VAW on a broader scale and to inform and support possible short-term and long-term changes in the client experience and counselling practice.

Keywords: COVID-19, pandemic, virtual, violence against women (VAW)

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52 An Argument for Agile, Lean, and Hybrid Project Management in Museum Conservation Practice: A Qualitative Evaluation of the Morris Collection Conservation Project at the Sainsbury Centre for Visual Arts

Authors: Maria Ledinskaya

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This paper is part case study and part literature review. It seeks to introduce Agile, Lean, and Hybrid project management concepts from business, software development, and manufacturing fields to museum conservation by looking at their practical application on a recent conservation project at the Sainsbury Centre for Visual Arts. The author outlines the advantages of leaner and more agile conservation practices in today’s faster, less certain, and more budget-conscious museum climate where traditional project structures are no longer as relevant or effective. The Morris Collection Conservation Project was carried out in 2019-2021 in Norwich, UK, and concerned the remedial conservation of around 150 Abstract Constructivist artworks bequeathed to the Sainsbury Centre by private collectors Michael and Joyce Morris. It was a medium-sized conservation project of moderate complexity, planned and delivered in an environment with multiple known unknowns – unresearched collection, unknown conditions and materials, unconfirmed budget. The project was later impacted by the COVID-19 pandemic, introducing indeterminate lockdowns, budget cuts, staff changes, and the need to accommodate social distancing and remote communications. The author, then a staff conservator at the Sainsbury Centre who acted as project manager on the Morris Project, presents an incremental, iterative, and value-based approach to managing a conservation project in an uncertain environment. The paper examines the project from the point of view of Traditional, Agile, Lean, and Hybrid project management. The author argues that most academic writing on project management in conservation has focussed on a Traditional plan-driven approach – also known as Waterfall project management – which has significant drawbacks in today’s museum environment due to its over-reliance on prediction-based planning and its low tolerance to change. In the last 20 years, alternative Agile, Lean and Hybrid approaches to project management have been widely adopted in software development, manufacturing, and other industries, although their recognition in the museum sector has been slow. Using examples from the Morris Project, the author introduces key principles and tools of Agile, Lean, and Hybrid project management and presents a series of arguments on the effectiveness of these alternative methodologies in museum conservation, including the ethical and practical challenges to their implementation. These project management approaches are discussed in the context of consequentialist, relativist, and utilitarian developments in contemporary conservation ethics. Although not intentionally planned as such, the Morris Project had a number of Agile and Lean features which were instrumental to its successful delivery. These key features are identified as distributed decision-making, a co-located cross-disciplinary team, servant leadership, focus on value-added work, flexible planning done in shorter sprint cycles, light documentation, and emphasis on reducing procedural, financial, and logistical waste. Overall, the author’s findings point in favour of a hybrid model, which combines traditional and alternative project processes and tools to suit the specific needs of the project.

Keywords: agile project management, conservation, hybrid project management, lean project management, waterfall project management

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51 Evaluation of Toxicity of Cerium Oxide on Zebrafish Developmental Stages

Authors: Roberta Pecoraro, Elena Maria Scalisi

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Engineered Nanoparticles (ENPs) and Nanomaterials (ENMs) concern an active research area and a sector in full expansion. They have physical-chemical characteristics and small size that improve their performance compared to common materials. Due to the increase in their production and their subsequent release into the environment, new strategies are emerging to assess risk of nanomaterials. NPs can be released into the environment through aquatic systems by human activities and exert toxicity on living organisms. We evaluated the potential toxic effect of cerium oxide (CeO2) nanoparticles because it’s used in different fields due to its peculiar properties. In order to assess nanoparticles toxicity, Fish Embryo Toxicity (FET) test was performed. Powders of CeO2 NPs supplied by the CNR-IMM of Catania are indicated as CeO2 type 1 (as-prepared) and CeO2 type 2 (modified), while CeO2 type 3 (commercial) is supplied by Sigma-Aldrich. Starting from a stock solution (0.001g/10 ml dilution water) of each type of CeO2 NPs, the other concentration solutions were obtained adding 1 ml of the stock solution to 9 ml of dilution water, leading to three different solutions of concentration (10-4, 10-5, 10-6 g/ml). All the solutions have been sonicated to avoid natural tendency of NPs to aggregate and sediment. FET test was performed according to the OECD guidelines for testing chemicals using our internal protocol procedure. A number of eight selected fertilized eggs were placed in each becher filled with 5 ml of each concentration of the three types of CeO2 NPs; control samples were incubated only with dilution water. Replication was performed for each concentration. During the exposure period, we observed four endpoints (embryo coagulation, lack of formation of somites, failure to lift the yolk bag, no heartbeat) by a stereomicroscope every 24 hours. Immunohistochemical analysis on treated larvae was performed to evaluate the expression of metallothioneins (MTs), Heat Shock Proteins 70 (HSP70) and 7-ethoxyresorufin-O-diethylase (EROD). Our results have not shown evident alterations on embryonic development because all embryos completed the development and the hatching of the eggs, started around the 48th hour after exposure, took place within the last observation at 72 hours. A good reactivity, both in the embryos and in the newly hatched larvae, was found. The presence of heartbeat has also been observed in embryos with reduced mobility confirming their viability. A higher expression of EROD biomarker was observed in the larvae exposed to the three types of CeO2, showing a clear difference with the control. A weak positivity was found for MTs biomarker in treated larvae as well as in the control. HSP70 are expressed homogeneously in all the type of nanoparticles tested but not too much greater than control. Our results are in agreement with other studies in the literature, in which the exposure of Danio rerio larvae to other metal oxide nanoparticles does not show adverse effects on survival and hatching time. Further studies are necessary to clarify the role of these NPs and also to solve conflicting opinions.

Keywords: Danio rerio, endpoints, fish embryo toxicity test, metallic nanoparticles

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50 Oat Bran Associated with Nutritional Counseling in Treating Obesity and Other Risk Factors for Cardiovascular Disease

Authors: Simone Raimondi De Souza, Glaucia Maria Moraes De Oliveira, Ronir Raggio Luiz, Glorimar Rosa

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Introduction: Obesity is among the main risk factors for cardiovascular disease (CVD). Genesis is multifactorial, including genetic, hormonal and environmental factors disorders, among which inadequate feeding pattern, for which nutritional counseling strategies have proven effective. The consumption of beta-glucans (soluble fibers that reportedly promote satiety) present in oat bran can be an effective strategy for preventing and treating obesity. Other benefits have been observed with oat bran consumption, such as reduction of hypercholesterolemia and hyperglycemia, two other risk factors for CVD. Objectives: To analyze the effect of oat bran consumption associated with nutritional counseling in reducing body mass index (BMI), blood cholesterol, glucose profile, waist and neck circumference in obese individuals, and to evaluate the change in eating pattern. Methods: clinical trial, randomized, double-blind, placebo-controlled, lasting 90 days with adults of both genders, with BMI ≥30kg/m2. The study was approved by the Ethics in Research involving human beings in a public institute of cardiology, in Rio de Janeiro, Brazil. Individuals were invited to participate and accepted formally by signing the Terms of Consent. Participants were randomized into oat bran group (gOB) or placebo group (gPCB) and received, respectively: morning prepared consisting of 40g oat bran, 30g of skimmed milk powder and 1g sweetener sucralose; refined flour 40g rice, 30g of milk powder and 1g sweetener sucralose. The Ten Steps to Healthy Eating, of Brazilian Ministry of Health were used to support the nutritional counseling. Variables analyzed: gender; age; BMI, waist circumference (WC) neck circumference (NC); systolic blood pressure (SBP); diastolic blood pressure (DBP); food consumption, total cholesterol (TC), LDL-cholesterol (LDL-c), HDL-cholesterol (HDL-c), non-HDL cholesterol (nHDLc), triglycerides (TG), fasting glucose (FG), fasting insulin (FI) and HOMA-IR. Dietary intake was assessed by 24-hour dietary recall. The Diet Quality Index revised for the Brazilian population (IQD-R) assessed quality of feeding pattern. Statistical analyzes were performed using SPSS version 21, considering statistically significant p-value less than 0.05. Results: A total of 38 participants were included, age = 50 ± 7,6years, 63% women. 19 subjects were placed in gOB and 19 in gPCB. After intervention, statistically significant reductions were observed in the following parameters: in gOB: IQD-R, TC, LDL-c, nHDL-c, FI, SBP, DBP, BMI, WC, NC; in gPCB: IQD-R, LDL-c, SBP, DBP, BMI, WC, NC. No statistically significant differences were observed in the results between groups. Conclusion: Our results reinforce nutritional counseling as important strategy for prevention and treatment of obesity and suggest that inclusion of oat bran in daily diet can bring additional benefits controlling risk factors for CVD. More studies are needed to establish all benefits of oat bran to human health as well as the ideal daily dose for consumption.

Keywords: oat bran, cardiovascular disease, nutritional counseling, obesity

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49 A Model to Assess Sustainability Using Multi-Criteria Analysis and Geographic Information Systems: A Case Study

Authors: Antonio Boggia, Luisa Paolotti, Gianluca Massei, Lucia Rocchi, Elaine Pace, Maria Attard

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The aim of this paper is to present a methodology and a computer model for sustainability assessment based on the integration of Multi-criteria Decision Analysis (MCDA) with a Geographic Information System (GIS). It presents the result of a study for the implementation of a model for measuring sustainability to address the policy actions for the improvement of sustainability at territory level. The aim is to rank areas in order to understand the specific technical and/or financial support that is required to develop sustainable growth. Assessing sustainable development is a multidimensional problem: economic, social and environmental aspects have to be taken into account at the same time. The tool for a multidimensional representation is a proper set of indicators. The set of indicators must be integrated into a model, that is an assessment methodology, to be used for measuring sustainability. The model, developed by the Environmental Laboratory of the University of Perugia, is called GeoUmbriaSUIT. It is a calculation procedure developed as a plugin working in the open-source GIS software QuantumGIS. The multi-criteria method used within GeoUmbriaSUIT is the algorithm TOPSIS (Technique for Order Preference by Similarity to Ideal Design), which defines a ranking based on the distance from the worst point and the closeness to an ideal point, for each of the criteria used. For the sustainability assessment procedure, GeoUmbriaSUIT uses a geographic vector file where the graphic data represent the study area and the single evaluation units within it (the alternatives, e.g. the regions of a country, or the municipalities of a region), while the alphanumeric data (attribute table), describe the environmental, economic and social aspects related to the evaluation units by means of a set of indicators (criteria). The use of the algorithm available in the plugin allows to treat individually the indicators representing the three dimensions of sustainability, and to compute three different indices: environmental index, economic index and social index. The graphic output of the model allows for an integrated assessment of the three dimensions, avoiding aggregation. The presence of separate indices and graphic output make GeoUmbriaSUIT a readable and transparent tool, since it doesn’t produce an aggregate index of sustainability as final result of the calculations, which is often cryptic and difficult to interpret. In addition, it is possible to develop a “back analysis”, able to explain the positions obtained by the alternatives in the ranking, based on the criteria used. The case study presented is an assessment of the level of sustainability in the six regions of Malta, an island state in the middle of the Mediterranean Sea and the southernmost member of the European Union. The results show that the integration of MCDA-GIS is an adequate approach for sustainability assessment. In particular, the implemented model is able to provide easy to understand results. This is a very important condition for a sound decision support tool, since most of the time decision makers are not experts and need understandable output. In addition, the evaluation path is traceable and transparent.

Keywords: GIS, multi-criteria analysis, sustainability assessment, sustainable development

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48 Improvement of Autism Diagnostic Observation Schedule Scores after Comprehensive Intensive Early Interventions in a Clinical Setting

Authors: Nils Haglund, Svenolof Dahlgren, Maria Rastam, Peik Gustafsson, Karin Kalien

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In Sweden, like in most developed countries, there is a substantial increase of children diagnosed with autism and other conditions within the autism spectrum (ASD). The rapid increase of ASD rates stresses the importance of developing care programs to provide support and comprehensive interventions for affected families. The current observational study was conducted in order to evaluate an ongoing Comprehensive Intensive Early Intervention (CIEI) program for children with autism in southern Sweden. The change in autism symptoms among children participating in CIEI (intervention group, n=67) was compared with children who received traditional habilitation services only (comparison group, n=27). Children of parents who accepted the offered CIEI-program, constituted the intervention group, whereas children, whose parents (for some reason) were not interested in the offered CIEI-program, constituted the comparison group. The CIEI-program was individualized to each child by experienced applied behavior analysis (ABA) specialists with different backgrounds as psychologists, speech pathologists or special education teachers, in cooperation with parents and preschool staff. Due to the individualization, the intervention could vary in intensity and techniques. The intensity was calculated to 15-25 hours each week at home and the preschool altogether. Each child was assigned one 'trainer', who was often employed as a preschool teacher but could have another educational background. An agreement between supervisor- parents and preschool staff was reached to confirm the intensity and content of the CIEI- program over an approximately two-year intervention period. Symptom changes were measured as evaluation-ADOS-2-scores, total- and severity-scores, minus the corresponding baseline-scores, divided by the time between baseline and evaluation. The difference between the study-groups regarding change of ADOS-2-scores was estimated using ANCOVA. In the current study, children in the CIEI-group improved their ADOS-2-total scores between baseline and evaluation (-0.8 scores per year; 95%CI: -1.2 to -0.4), whereas no such improvement was detected in the comparison group (+0.1 scores per year; 95%CI: -0.7 to +0.9). The change difference (change in the CIEI-group vs. change in the comparison group) was statistically significant, both crude and after adjusting for possible confounders (-1.1; 95%CI -1.9 to -0.4). Children in the CIEI-group also significantly improved their ADOS-calibrated severity scores, but not significantly differently so from the comparison group. The results from the current study indicate that the CIEI program significantly improves social and communicative skills among children with autism and that children with developmental delay could benefit to a similar degree as other children. The results support earlier studies reporting on the improvement of autism symptoms after early intensive interventions. The results from observational studies are difficult to interpret, but it is nevertheless of uttermost importance to evaluate costly autism intervention programs. Such results may be of immediate importance to healthcare organizations when allocating the already strained resources to different patient groups. Albeit the obvious limitation of the current naturalistic study, the results support previous positive studies and indicate that children with autism benefit from participating in early comprehensive, intensive programs and that investments in these programs may be highly justifiable.

Keywords: autism symptoms, ADOS-scores, evaluation, intervention program

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47 Analyzing the Heat Transfer Mechanism in a Tube Bundle Air-PCM Heat Exchanger: An Empirical Study

Authors: Maria De Los Angeles Ortega, Denis Bruneau, Patrick Sebastian, Jean-Pierre Nadeau, Alain Sommier, Saed Raji

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Phase change materials (PCM) present attractive features that made them a passive solution for thermal comfort assessment in buildings during summer time. They show a large storage capacity per volume unit in comparison with other structural materials like bricks or concrete. If their use is matched with the peak load periods, they can contribute to the reduction of the primary energy consumption related to cooling applications. Despite these promising characteristics, they present some drawbacks. Commercial PCMs, as paraffines, offer a low thermal conductivity affecting the overall performance of the system. In some cases, the material can be enhanced, adding other elements that improve the conductivity, but in general, a design of the unit that optimizes the thermal performance is sought. The material selection is the departing point during the designing stage, and it does not leave plenty of room for optimization. The PCM melting point depends highly on the atmospheric characteristics of the building location. The selection must relay within the maximum, and the minimum temperature reached during the day. The geometry of the PCM container and the geometrical distribution of these containers are designing parameters, as well. They significantly affect the heat transfer, and therefore its phenomena must be studied exhaustively. During its lifetime, an air-PCM unit in a building must cool down the place during daytime, while the melting of the PCM occurs. At night, the PCM must be regenerated to be ready for next uses. When the system is not in service, a minimal amount of thermal exchanges is desired. The aforementioned functions result in the presence of sensible and latent heat storage and release. Hence different types of mechanisms drive the heat transfer phenomena. An experimental test was designed to study the heat transfer phenomena occurring in a circular tube bundle air-PCM exchanger. An in-line arrangement was selected as the geometrical distribution of the containers. With the aim of visual identification, the containers material and a section of the test bench were transparent. Some instruments were placed on the bench for measuring temperature and velocity. The PCM properties were also available through differential scanning calorimeter (DSC) tests. An evolution of the temperature during both cycles, melting and solidification were obtained. The results showed some phenomena at a local level (tubes) and on an overall level (exchanger). Conduction and convection appeared as the main heat transfer mechanisms. From these results, two approaches to analyze the heat transfer were followed. The first approach described the phenomena in a single tube as a series of thermal resistances, where a pure conduction controlled heat transfer was assumed in the PCM. For the second approach, the temperature measurements were used to find some significant dimensionless numbers and parameters as Stefan, Fourier and Rayleigh numbers, and the melting fraction. These approaches allowed us to identify the heat transfer phenomena during both cycles. The presence of natural convection during melting might have been stated from the influence of the Rayleigh number on the correlations obtained.

Keywords: phase change materials, air-PCM exchangers, convection, conduction

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46 Absolute Quantification of the Bexsero Vaccine Component Factor H Binding Protein (fHbp) by Selected Reaction Monitoring: The Contribution of Mass Spectrometry in Vaccinology

Authors: Massimiliano Biagini, Marco Spinsanti, Gabriella De Angelis, Sara Tomei, Ilaria Ferlenghi, Maria Scarselli, Alessia Biolchi, Alessandro Muzzi, Brunella Brunelli, Silvana Savino, Marzia M. Giuliani, Isabel Delany, Paolo Costantino, Rino Rappuoli, Vega Masignani, Nathalie Norais

Abstract:

The gram-negative bacterium Neisseria meningitidis serogroup B (MenB) is an exclusively human pathogen representing the major cause of meningitides and severe sepsis in infants and children but also in young adults. This pathogen is usually present in the 30% of healthy population that act as a reservoir, spreading it through saliva and respiratory fluids during coughing, sneezing, kissing. Among surface-exposed protein components of this diplococcus, factor H binding protein is a lipoprotein proved to be a protective antigen used as a component of the recently licensed Bexsero vaccine. fHbp is a highly variable meningococcal protein: to reflect its remarkable sequence variability, it has been classified in three variants (or two subfamilies), and with poor cross-protection among the different variants. Furthermore, the level of fHbp expression varies significantly among strains, and this has also been considered an important factor for predicting MenB strain susceptibility to anti-fHbp antisera. Different methods have been used to assess fHbp expression on meningococcal strains, however, all these methods use anti-fHbp antibodies, and for this reason, the results are affected by the different affinity that antibodies can have to different antigenic variants. To overcome the limitations of an antibody-based quantification, we developed a quantitative Mass Spectrometry (MS) approach. Selected Reaction Monitoring (SRM) recently emerged as a powerful MS tool for detecting and quantifying proteins in complex mixtures. SRM is based on the targeted detection of ProteoTypicPeptides (PTPs), which are unique signatures of a protein that can be easily detected and quantified by MS. This approach, proven to be highly sensitive, quantitatively accurate and highly reproducible, was used to quantify the absolute amount of fHbp antigen in total extracts derived from 105 clinical isolates, evenly distributed among the three main variant groups and selected to be representative of the fHbp circulating subvariants around the world. We extended the study at the genetic level investigating the correlation between the differential level of expression and polymorphisms present within the genes and their promoter sequences. The implications of fHbp expression on the susceptibility of the strain to killing by anti-fHbp antisera are also presented. To date this is the first comprehensive fHbp expression profiling in a large panel of Neisseria meningitidis clinical isolates driven by an antibody-independent MS-based methodology, opening the door to new applications in vaccine coverage prediction and reinforcing the molecular understanding of released vaccines.

Keywords: quantitative mass spectrometry, Neisseria meningitidis, vaccines, bexsero, molecular epidemiology

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45 Reproductive Biology and Lipid Content of Albacore Tuna (Thunnus alalunga) in the Western Indian Ocean

Authors: Zahirah Dhurmeea, Iker Zudaire, Heidi Pethybridge, Emmanuel Chassot, Maria Cedras, Natacha Nikolic, Jerome Bourjea, Wendy West, Chandani Appadoo, Nathalie Bodin

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Scientific advice on the status of fish stocks relies on indicators that are based on strong assumptions on biological parameters such as condition, maturity and fecundity. Currently, information on the biology of albacore tuna, Thunnus alalunga, in the Indian Ocean is scarce. Consequently, many parameters used in stock assessment models for Indian Ocean albacore originate largely from other studied stocks or species of tuna. Inclusion of incorrect biological data in stock assessment models would lead to inappropriate estimates of stock status used by fisheries manager’s to establish future catch allowances. The reproductive biology of albacore tuna in the western Indian Ocean was examined through analysis of the sex ratio, spawning season, length-at-maturity (L50), spawning frequency, fecundity and fish condition. In addition, the total lipid content (TL) and lipid class composition in the gonads, liver and muscle tissues of female albacore during the reproductive cycle was investigated. A total of 923 female and 867 male albacore were sampled from 2013 to 2015. A bias in sex-ratio was found in favour of females with fork length (LF) <100 cm. Using histological analyses and gonadosomatic index, spawning was found to occur between 10°S and 30°S, mainly to the east of Madagascar from October to January. Large females contributed more to reproduction through their longer spawning period compared to small individuals. The L50 (mean ± standard error) of female albacore was estimated at 85.3 ± 0.7 cm LF at the vitellogenic 3 oocyte stage maturity threshold. Albacore spawn on average every 2.2 days within the spawning region and spawning months from November to January. Batch fecundity varied between 0.26 and 2.09 million eggs and the relative batch fecundity (mean  standard deviation) was estimated at 53.4 ± 23.2 oocytes g-1 of somatic-gutted weight. Depending on the maturity stage, TL in ovaries ranged from 7.5 to 577.8 mg g-1 of wet weight (ww) with different proportions of phospholipids (PL), wax esters (WE), triacylglycerol (TAG) and sterol (ST). The highest TL were observed in immature (mostly TAG and PL) and spawning capable ovaries (mostly PL, WE and TAG). Liver TL varied from 21.1 to 294.8 mg g-1 (ww) and acted as an energy (mainly TAG and PL) storage prior to reproduction when the lowest TL was observed. Muscle TL varied from 2.0 to 71.7 g-1 (ww) in mature females without a clear pattern between maturity stages, although higher values of up to 117.3 g-1 (ww) was found in immature females. TL results suggest that albacore could be viewed predominantly as a capital breeder relying mostly on lipids stored before the onset of reproduction and with little additional energy derived from feeding. This study is the first one to provide new information on the reproductive development and classification of albacore in the western Indian Ocean. The reproductive parameters will reduce uncertainty in current stock assessment models which will eventually promote sustainability of the fishery.

Keywords: condition, size-at-maturity, spawning behaviour, temperate tuna, total lipid content

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44 Surveillance of Artemisinin Resistance Markers and Their Impact on Treatment Outcomes in Malaria Patients in an Endemic Area of South-Western Nigeria

Authors: Abiodun Amusan, Olugbenga Akinola, Kazeem Akano, María Hernández-Castañeda, Jenna Dick, Akintunde Sowunmi, Geoffrey Hart, Grace Gbotosho

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Introduction: Artemisinin-based Combination Therapy (ACTs) is the cornerstone malaria treatment option in most malaria-endemic countries. Unfortunately, the malaria control effort is constantly being threatened by resistance of Plasmodium falciparum to ACTs. The recent evidence of artemisinin resistance in East Africa and its possibility of spreading to other African regions portends an imminent health catastrophe. This study aimed at evaluating the occurrence, prevalence, and influence of artemisinin-resistance markers on treatment outcomes in Ibadan before and after post-adoption of artemisinin combination therapy (ACTs) in Nigeria in 2005. Method: The study involved day zero dry blood spot (DBS) obtained from malaria patients during retrospective (2000-2005) and prospective (2021) studies. A cohort in the prospective study received oral dihydroartemisinin-piperaquine and underwent a 42-day follow-up to observe treatment outcomes. Genomic DNA was extracted from the DBS samples using a QIAamp blood extraction kit. Fragments of P. falciparum kelch13 (Pfkelch13), P. falciparum coronin (Pfcoronin), P. falciparum multidrug resistance 2 (PfMDR2), and P. falciparum chloroquine resistance transporter (PfCRT) genes were amplified and sequenced on a sanger sequencing platform to identify artemisinin resistance-associated mutations. Mutations were identified by aligning sequenced data with reference sequences obtained from the National Center for Biotechnology Information. Data were analyzed using descriptive statistics and student t-tests. Results: Mean parasite clearance time (PCT) and fever clearance time (FCT) were 2.1 ± 0.6 days (95% CI: 1.97-2.24) and 1.3 ± 0.7 days (95% CI: 1.1-1.6) respectively. Four mutations, K189T [34/53(64.2%)], R255K [2/53(3.8%)], K189N [1/53(1.9%)] and N217H [1/53(1.9%)] were identified within the N-terminal (Coiled-coil containing) domain of Pfkelch13. No artemisinin resistance-associated mutation usually found within the β-propeller domain of the Pfkelch13 gene was found in these analyzed samples. However, K189T and R255K mutations showed a significant correlation with longer parasite clearance time in the patients (P<0.002). The observed Pfkelch13 gene changes did not influence the baseline mean parasitemia (P = 0.44). P76S [17/100 (17%)] and V62M [1/100 (1%)] changes were identified in the Pfcoronin gene fragment without any influence on the parasitological parameters. No change was observed in the PfMDR2 gene, while no artemisinin resistance-associated mutation was found in the PfCRT gene. Furthermore, a sample each in the retrospective study contained the Pfkelch13 K189T and Pfcoronin P76S mutations. Conclusion: The study revealed absence of genetic-based evidence of artemisinin resistance in the study population at the time of study. The high frequency of K189T Pfkelch13 mutation and its correlation with increased parasite clearance time in this study may depict geographical variation of resistance mediators and imminent artemisinin resistance, respectively. The study also revealed an inherent potential of parasites to harbour drug-resistant genotypes before the introduction of ACTs in Nigeria.

Keywords: artemisinin resistance, plasmodium falciparum, Pfkelch13 mutations, Pfcoronin

Procedia PDF Downloads 49
43 Chemical Synthesis and Microwave Sintering of SnO2-Based Nanoparticles for Varistor Films

Authors: Glauco M. M. M. Lustosa, João Paulo C. Costa, Leinig Antônio Perazolli, Maria Aparecida Zaghete

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SnO2 has electrical conductivity due to the excess of electrons and structural defects, being its electrical behavior highly dependent on sintering temperature and chemical composition. The addition of metals modifiers into the crystalline structure can improve and controlling the behavior of some semiconductor oxides that can therefore develop different applications such as varistors (ceramic with non-ohmic behavior between current and voltage, i.e. conductive during normal operation and resistive during overvoltage). The polymeric precursor method, based on the complexation reaction between metal ion and policarboxylic acid and then polymerized with ethylene glycol, was used to obtain nanopowders ceramic. The metal immobilization reduces its segregation during the decomposition of the polyester resulting in a crystalline oxide with high chemical homogeneity. The preparation of films from ceramics nanoparticles using electrophoretic deposition method (EPD) brings prospects for a new generation of smaller size devices with easy integration technology. EPD allows to control time and current and therefore it can have control of the thickness, surface roughness and the film density, quickly and with low production costs. The sintering process is key to control size and grain boundary density of the film. In this step, there is the diffusion of metals that promote densification and control of intrinsic defects or change these defects which will form and modify the potential barrier in the grain boundary. The use of microwave oven for sintering is an advantageous process due to the fast and homogeneous heating rate, promoting the diffusion and densification without irregular grain growth. This research was done a comparative study of sintering temperature by use of zinc as modifier agent to verify the influence on sintering step aiming to promote densification and grain growth, which influences the potential barrier formation and then changed the electrical behavior. SnO2-nanoparticles were obtained with 1 %mol of ZnO + 0.05 %mol of Nb2O5 (SZN), deposited as film through EPD (voltage 2 kV, time of 10 min) on Si/Pt substrate. Sintering was made in a microwave oven at 800, 900 and 1000 °C. For complete coverage of the substrate by nanoparticles with low surface roughness and uniform thickness was added 0.02 g of solid iodine in alcoholic suspension SnO2 to increase particle surface charge. They were also used magneto in EPD system that improved the deposition rate forming a compact film. Using a scanning electron microscope of high resolution (SEM_FEG) it was observed nanoparticles with average size between 10-20 nm, after sintering the average size was 150 to 200 nm and thickness of 5 µm. Also, it was verified that the temperature at 1000 °C was the most efficient in sintering. The best sintering time was also recorded and determined as 40 minutes. After sintering, the films were recovered with Cr3+ ions layer by EPD, then the films were again thermally treated. The electrical characterizations (nonlinear coefficient of 11.4, voltage rupture of ~60 V and leakage current = 4.8x10−6 A), allow considering the new methodology suitable for prepare SnO2-based varistor applied for development of electrical protection devices for low voltage.

Keywords: chemical synthesis, electrophoretic deposition, microwave sintering, tin dioxide

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42 Backward-Facing Step Measurements at Different Reynolds Numbers Using Acoustic Doppler Velocimetry

Authors: Maria Amelia V. C. Araujo, Billy J. Araujo, Brian Greenwood

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The flow over a backward-facing step is characterized by the presence of flow separation, recirculation and reattachment, for a simple geometry. This type of fluid behaviour takes place in many practical engineering applications, hence the reason for being investigated. Historically, fluid flows over a backward-facing step have been examined in many experiments using a variety of measuring techniques such as laser Doppler velocimetry (LDV), hot-wire anemometry, particle image velocimetry or hot-film sensors. However, some of these techniques cannot conveniently be used in separated flows or are too complicated and expensive. In this work, the applicability of the acoustic Doppler velocimetry (ADV) technique is investigated to such type of flows, at various Reynolds numbers corresponding to different flow regimes. The use of this measuring technique in separated flows is very difficult to find in literature. Besides, most of the situations where the Reynolds number effect is evaluated in separated flows are in numerical modelling. The ADV technique has the advantage in providing nearly non-invasive measurements, which is important in resolving turbulence. The ADV Nortek Vectrino+ was used to characterize the flow, in a recirculating laboratory flume, at various Reynolds Numbers (Reh = 3738, 5452, 7908 and 17388) based on the step height (h), in order to capture different flow regimes, and the results compared to those obtained using other measuring techniques. To compare results with other researchers, the step height, expansion ratio and the positions upstream and downstream the step were reproduced. The post-processing of the AVD records was performed using a customized numerical code, which implements several filtering techniques. Subsequently, the Vectrino noise level was evaluated by computing the power spectral density for the stream-wise horizontal velocity component. The normalized mean stream-wise velocity profiles, skin-friction coefficients and reattachment lengths were obtained for each Reh. Turbulent kinetic energy, Reynolds shear stresses and normal Reynolds stresses were determined for Reh = 7908. An uncertainty analysis was carried out, for the measured variables, using the moving block bootstrap technique. Low noise levels were obtained after implementing the post-processing techniques, showing their effectiveness. Besides, the errors obtained in the uncertainty analysis were relatively low, in general. For Reh = 7908, the normalized mean stream-wise velocity and turbulence profiles were compared directly with those acquired by other researchers using the LDV technique and a good agreement was found. The ADV technique proved to be able to characterize the flow properly over a backward-facing step, although additional caution should be taken for measurements very close to the bottom. The ADV measurements showed reliable results regarding: a) the stream-wise velocity profiles; b) the turbulent shear stress; c) the reattachment length; d) the identification of the transition from transitional to turbulent flows. Despite being a relatively inexpensive technique, acoustic Doppler velocimetry can be used with confidence in separated flows and thus very useful for numerical model validation. However, it is very important to perform adequate post-processing of the acquired data, to obtain low noise levels, thus decreasing the uncertainty.

Keywords: ADV, experimental data, multiple Reynolds number, post-processing

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41 Improving Junior Doctor Induction Through the Use of Simple In-House Mobile Application

Authors: Dmitriy Chernov, Maria Karavassilis, Suhyoun Youn, Amna Izhar, Devasenan Devendra

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Introduction and Background: A well-structured and comprehensive departmental induction improves patient safety and job satisfaction amongst doctors. The aims of our Project were as follows: 1. Assess the perceived preparedness of junior doctors starting their rotation in Acute Medicine at Watford General Hospital. 2. Develop a supplemental Induction Guide and Pocket reference in the form of an iOS mobile application. 3. To collect feedback after implementing the mobile application following a trial period of 8 weeks with a small cohort of junior doctors. Materials and Methods: A questionnaire was distributed to all new junior trainees starting in the department of Acute Medicine to assess their experience of current induction. A mobile Induction application was developed and trialled over a period of 8 weeks, distributed in addition to the existing didactic induction session. After the trial period, the same questionnaire was distributed to assess improvement in induction experience. Analytics data were collected with users’ consent to gauge user engagement and identify areas of improvement of the application. A feedback survey about the app was also distributed. Results: A total of 32 doctors used the application during the 8-week trial period. The application was accessed 7259 times in total, with the average user spending a cumulative of 37 minutes 22 seconds on the app. The most used section was Clinical Guidelines, accessed 1490 times. The App Feedback survey revealed positive reviews: 100% of participants (n=15/15) responded that the app improved their overall induction experience compared to other placements; 93% (n=14/15) responded that the app improved overall efficiency in completing daily ward jobs compared to previous rotations; and 93% (n=14/15) responded that the app improved patient safety overall. In the Pre-App and Post-App Induction Surveys, participants reported: a 48% improvement in awareness of practical aspects of the job; a 26% improvement of awareness on locating pathways and clinical guidelines; a 40% reduction of feelings of overwhelmingness. Conclusions and recommendations: This study demonstrates the importance of technology in Medical Education and Clinical Induction. The mobile application average engagement time equates to over 20 cumulative hours of on-the-job training delivered to each user, within an 8-week period. The most used and referred to section was clinical guidelines. This shows that there is high demand for an accessible pocket guide for this type of material. This simple mobile application resulted in a significant improvement in feedback about induction in our Department of Acute Medicine, and will likely impact workplace satisfaction. Limitations of the application include: post-app surveys had a small number of participants; the app is currently only available for iPhone users; some useful sections are nested deep within the app, lacks deep search functionality across all sections; lacks real time user feedback; and requires regular review and updates. Future steps for the app include: developing a web app, with an admin dashboard to simplify uploading and editing content; a comprehensive search functionality; and a user feedback and peer ratings system.

Keywords: mobile app, doctor induction, medical education, acute medicine

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40 Opportunities in Self-care Abortion and Telemedicine: Findings from a Study in Colombia

Authors: Paola Montenegro, Maria de los Angeles Balaguera Villa

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In February 2022 Colombia achieved a historic milestone in ensuring universal access to abortion rights with ruling C-055 of 2022 decriminalising abortion up to 24 weeks of gestation. In the context of this triumph and the expansion of telemedicine services in the wake of the COVID-19 pandemic, this research studied the acceptability of self-care abortion in young people (13 - 28 years) through a telemedicine service and also explored the primary needs that should be the focus of such care. The results shine light on a more comprehensive understanding of opportunities and challenges of teleabortion practices in a context that combines overall higher access to technology and low access to reliable information of safe abortion, stigma, and scarcity especially felt by transnational migrants, racialised people, trans men and non-binary people. Through a mixed methods approach, this study collected 5.736 responses to a virtual survey disseminated nationwide in Colombia and 47 in-person interviews (24 of them with people who were assigned female at birth and 21 with local key stakeholders in the abortion ecosystem). Quantitative data was analyzed using Stata SE Version 16.0 and qualitative analysis was completed through NVivo using thematic analysis. Key findings of the research suggest that self-care abortion is practice with growing acceptability among young people, but important adjustments must be made to meet quality of care expectations of users. Elements like quick responses from providers, lower costs, and accessible information were defined by users as decisive factors to choose over the abortion service provider. In general, the narratives in participants about quality care were centred on the promotion of autonomy and the provision of accompaniment and care practices, also perceived as transformative and currently absent of most health care services. The most staggering findings from the investigation are related to current barriers faced by young people in abortion contexts even when the legal barriers have: high rates of scepticism and distrust associated with pitfalls of telehealth and structural challenges associated with lacking communications infrastructure, among a few of them. Other important barriers to safe self-care abortion identified by participants surfaced like lack of privacy and confidentiality (especially in rural areas of the country), difficulties accessing reliable information, high costs of procedures and expenses related to travel costs or having to cease economic activities, waiting times, and stigma are among the primary barriers to abortion identified by participants. Especially in a scenario marked by unprecedented social, political and economic disruptions due to the COVID-19 pandemic, the commitment to design better care services that can be adapted to the identities, experiences, social contexts and possibilities of the user population is more necessary than ever. In this sense, the possibility of expanding access to services through telemedicine brings us closer to the opportunity to rethink the role of health care models in transforming the role of individuals and communities to make autonomous, safe and informed decisions about their own health and well-being.

Keywords: contraception, family planning, premarital fertility, unplanned pregnancy

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39 Effect of Land Use and Abandonment on Soil Carbon and Nitrogen Depletion by Runoff in Shallow Soils under Semi-Arid Mediterranean Climate

Authors: Mohamed Emran, Giovanni Pardini, Maria Gispert, Mohamed Rashad

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Land use and abandonment in semi-arid degraded ecosystems may cause regressive dynamics in vegetation cover affecting organic matter contents, soil nutrients and structural stability, thus reducing soil resistance to erosion. Mediterranean areas are generally subjected to climatic fluctuations, which modify soil conditions and hydrological processes, such as runoff and water infiltration within the upper soil horizons. Low erosion rates occur in very fragile and shallow soils with minor clay content progressively decrease organic carbon C and nitrogen N pools in the upper soil horizons. Seven soils were selected representing variant context of land use and abandonment at the Cap de Creus Peninsula, Catalonia, NE Spain, from recent cultivated vines and olive groves, mid abandoned forests standing under cork and pine trees, pasture to late abandoned Cistus and Erica scrubs. The aim of this work was to study the effect of changes in land use and abandonment on the depletion of soil organic carbon and nitrogen transported by runoff water in shallow soils after natural rainfall events during two years with different rainfall patterns (1st year with low rainfall and 2nd year with high rainfall) by i) monitoring the most significant soil erosion parameters at recorded rainfall events, ii) studying the most relevant soil physical and chemical characteristics on seasonal basis and iii) analysing the seasonal trends of depleted carbon and nitrogen and their interaction with soil surface compaction parameters. Significant seasonal variability was observed in the relevant soil physical and chemical parameters and soil erosion parameters in all soils to establish their evolution under land use and abandonment during two years of different rainfall patterns (214 and 487 mm per year), giving important indications on soil response to rainfall impacts. Erosion rates decreased significantly with the increasing of soil C and N under low and high rainfall. In cultivated soils, C and N depletion increased by 144% and 115%, respectively by 13% increase in erosion rates during the 1st year with respect to the 2nd year. Depleted C and N were proportionally higher in soils under vines and olive with vulnerable soil structure and low soil resilience leading to degradation, altering nutrients cycles and causing adverse impact on environmental quality. Statistical analysis underlined that, during the 1st year, soil surface was less effective in preserving stocks of organic resources leading to higher susceptibility to erosion with consequent C and N depletion. During the 2nd year, higher organic reserve and water storage occurred despite the increasing of C and N loss with an effective contribution from soil surface compaction parameters. The overall estimation during the two years indicated clear differences among soils under vines, olive, cork and pines, suggesting on the one hand, that current cultivation practices are inappropriate and that reforestation with pines may delay the achievement of better soil conditions. On the other hand, the natural succession of vegetation under Cistus, pasture and Erica suggests the recovery of good soil conditions.

Keywords: land abandonment, land use, nutrient's depletion, soil erosion

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38 Nanocomposite Effect Based on Silver Nanoparticles and Anemposis Californica Extract as Skin Restorer

Authors: Maria Zulema Morquecho Vega, Fabiola CarolinaMiranda Castro, Rafael Verdugo Miranda, Ignacio Yocupicio Villegas, Ana lidia Barron Raygoza, Martin enrique MArquez Cordova, Jose Alberto Duarte Moller

Abstract:

Background: Anemopsis californica, also called (tame grass) belongs to the Saururaceae family small, green plant. The blade is long and wide. Gives a white flower. The plant population is only found in humid, swampy habitats, it grows where there is water, along the banks of streams and water holes. In the winter, it dries up. The leaves, rhizomes, or roots of this plant have been used to treat a range of diseases. Some of its healing properties are used to treat wounds, cold and flu symptoms, spasmodic cough, infection, pain and inflammation, burns, swollen feet, as well as lung ailments, asthma, circulatory problems (varicose veins), rheumatoid arthritis, purifies blood, helps in urinary and digestive tract diseases, sores and healing, for headache, sore throat, diarrhea, kidney pain. The tea made from the leaves and roots is used to treat uterine cancer, womb cancer, relieves menstrual pain and stops excessive bleeding after childbirth. It is also used as a gynecological treatment for infections, hemorrhoids, candidiasis and vaginitis. Objective: To study the cytotoxicity of gels prepared with silver nanoparticles in AC extract combined with chitosan, collagen and hyaluronic acid as an alternative therapy for skin conditions. Methods: The Ag NPs were synthesized according to the following method. A 0.3 mg/mL solution is prepared in 10 ml of deionized water, adjust to pH 12 with NaOH, stirring is maintained constant magnetic and a temperature of 80 °C. Subsequently, 100 ul of a 0.1 M AgNO3 solution and kept stirring constantly for 15 min. Once the reaction is complete, measurements are performed by UV-Vis. A gel was prepared in a 5% solution of acetic acid with the respective nanoparticles and AC extract of silver in the extract of AC. Chitosan is added until the process begins to occur gel. At that time, collagen will be added in a ratio of 3 to 5 drops, and later, hyaluronic acid in 2% of the total compound formed. Finally, after resting for 24 hours, the cytotoxic effect of the gels was studied. in the presence of highly positive bacteria Staphylococcus aureus and highly negative for Escherichia coli. Cultures will be incubated for 24 hours in the presence of the compound and compared with the reference. Results: Silver nanoparticles obtained had a spherical shape and sizes among 20 and 30 nm. UV-Vis spectra confirm the presence of silver nanoparticles showing a surface plasmon around 420 nm. Finally, the test in presence of bacteria yield a good antibacterial property of this nanocompound and tests in people were successful. Conclusion: Gel prepared by biogenic synthesis shown beneficious effects in severe acne, acne vulgaris and wound healing with diabetic patients.

Keywords: anemopsis californica, nanomedicina, biotechnology, biomedicine

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37 Urban Heat Islands Analysis of Matera, Italy Based on the Change of Land Cover Using Satellite Landsat Images from 2000 to 2017

Authors: Giuseppina Anna Giorgio, Angela Lorusso, Maria Ragosta, Vito Telesca

Abstract:

Climate change is a major public health threat due to the effects of extreme weather events on human health and on quality of life in general. In this context, mean temperatures are increasing, in particular, extreme temperatures, with heat waves becoming more frequent, more intense, and longer lasting. In many cities, extreme heat waves have drastically increased, giving rise to so-called Urban Heat Island (UHI) phenomenon. In an urban centre, maximum temperatures may be up to 10° C warmer, due to different local atmospheric conditions. UHI occurs in the metropolitan areas as function of the population size and density of a city. It consists of a significant difference in temperature compared to the rural/suburban areas. Increasing industrialization and urbanization have increased this phenomenon and it has recently also been detected in small cities. Weather conditions and land use are one of the key parameters in the formation of UHI. In particular surface urban heat island is directly related to temperatures, to land surface types and surface modifications. The present study concern a UHI analysis of Matera city (Italy) based on the analysis of temperature, change in land use and land cover, using Corine Land Cover maps and satellite Landsat images. Matera, located in Southern Italy, has a typical Mediterranean climate with mild winters and hot and humid summers. Moreover, Matera has been awarded the international title of the 2019 European Capital of Culture. Matera represents a significant example of vernacular architecture. The structure of the city is articulated by a vertical succession of dug layers sometimes excavated or partly excavated and partly built, according to the original shape and height of the calcarenitic slope. In this study, two meteorological stations were selected: MTA (MaTera Alsia, in industrial zone) and MTCP (MaTera Civil Protection, suburban area located in a green zone). In order to evaluate the increase in temperatures (in terms of UHI occurrences) over time, and evaluating the effect of land use on weather conditions, the climate variability of temperatures for both stations was explored. Results show that UHI phenomena is growing in Matera city, with an increase of maximum temperature values at a local scale. Subsequently, spatial analysis was conducted by Landsat satellite images. Four years was selected in the summer period (27/08/2000, 27/07/2006, 11/07/2012, 02/08/2017). In Particular, Landsat 7 ETM+ for 2000, 2006 and 2012 years; Landsat 8 OLI/TIRS for 2017. In order to estimate the LST, Mono Window Algorithm was applied. Therefore, the increase of LST values spatial scale trend has been verified, in according to results obtained at local scale. Finally, the analysis of land use maps over the years by the LST and/or the maximum temperatures measured, show that the development of industrialized area produces a corresponding increase in temperatures and consequently a growth in UHI.

Keywords: climate variability, land surface temperature, LANDSAT images, urban heat island

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36 Absorptive Capabilities in the Development of Biopharmaceutical Industry: The Case of Bioprocess Development and Research Unit, National Polytechnic Institute

Authors: Ana L. Sánchez Regla, Igor A. Rivera González, María del Pilar Monserrat Pérez Hernández

Abstract:

The ability of an organization to identify and get useful information from external sources, assimilate it, transform and apply to generate products or services with added value is called absorptive capacity. Absorptive capabilities contribute to have market opportunities to firms and get a leader position with respect to others competitors. The Bioprocess Development and Research Unit (UDIBI) is a Research and Development (R&D) laboratory that belongs to the National Polytechnic Institute (IPN), which is a higher education institute in Mexico. The UDIBI was created with the purpose of carrying out R and D activities for the Transferon®, a biopharmaceutical product developed and patented by IPN. The evolution of competence and scientific and technological platform made UDIBI expand its scope by providing technological services (preclínical studies and bio-compatibility evaluation) to the national pharmaceutical industry and biopharmaceutical industry. The relevance of this study is that those industries are classified as high scientific and technological intensity, and yet, after a review of the state of the art, there is only one study of absorption capabilities in biopharmaceutical industry with a similar scope to this research; in the case of Mexico, there is none. In addition to this, UDIBI belongs to a public university and its operation does not depend on the federal budget, but on the income generated by its external technological services. This fact represents a highly remarkable case in Mexico's public higher education context. This current doctoral research (2015-2019) is contextualized within a case study, its main objective is to identify and analyze the absorptive capabilities that characterise the UDIBI that allows it had become in a one of two third authorized laboratory by the sanitary authority in Mexico for developed bio-comparability studies to bio-pharmaceutical products. The development of this work in the field is divided into two phases. In a first phase, 15 interviews were conducted with the UDIBI personnel, covering management levels, heads of services, project leaders and laboratory personnel. These interviews were structured under a questionnaire, which was designed to integrate open questions and to a lesser extent, others, whose answers would be answered on a Likert-type rating scale. From the information obtained in this phase, a scientific article was made (in review and a proposal of presentation was submitted in different academic forums. A second stage will be made from the conduct of an ethnographic study within this organization under study that will last about 3 months. On the other hand, it is intended to carry out interviews with external actors around the UDIBI (suppliers, advisors, IPN officials, including contact with an academic specialized in absorption capacities to express their comments on this thesis. The inicial findings had shown two lines: i) exist institutional, technological and organizational management elements that encourage and/or limit the creation of absorption capacities in this scientific and technological laboratory and, ii) UDIBI has had created a set of multiple transfer technology of knowledge mechanisms which have had permitted to build a huge base of prior knowledge.

Keywords: absorptive capabilities, biopharmaceutical industry, high research and development intensity industries, knowledge management, transfer of knowledge

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35 A Single Cell Omics Experiments as Tool for Benchmarking Bioinformatics Oncology Data Analysis Tools

Authors: Maddalena Arigoni, Maria Luisa Ratto, Raffaele A. Calogero, Luca Alessandri

Abstract:

The presence of tumor heterogeneity, where distinct cancer cells exhibit diverse morphological and phenotypic profiles, including gene expression, metabolism, and proliferation, poses challenges for molecular prognostic markers and patient classification for targeted therapies. Understanding the causes and progression of cancer requires research efforts aimed at characterizing heterogeneity, which can be facilitated by evolving single-cell sequencing technologies. However, analyzing single-cell data necessitates computational methods that often lack objective validation. Therefore, the establishment of benchmarking datasets is necessary to provide a controlled environment for validating bioinformatics tools in the field of single-cell oncology. Benchmarking bioinformatics tools for single-cell experiments can be costly due to the high expense involved. Therefore, datasets used for benchmarking are typically sourced from publicly available experiments, which often lack a comprehensive cell annotation. This limitation can affect the accuracy and effectiveness of such experiments as benchmarking tools. To address this issue, we introduce omics benchmark experiments designed to evaluate bioinformatics tools to depict the heterogeneity in single-cell tumor experiments. We conducted single-cell RNA sequencing on six lung cancer tumor cell lines that display resistant clones upon treatment of EGFR mutated tumors and are characterized by driver genes, namely ROS1, ALK, HER2, MET, KRAS, and BRAF. These driver genes are associated with downstream networks controlled by EGFR mutations, such as JAK-STAT, PI3K-AKT-mTOR, and MEK-ERK. The experiment also featured an EGFR-mutated cell line. Using 10XGenomics platform with cellplex technology, we analyzed the seven cell lines together with a pseudo-immunological microenvironment consisting of PBMC cells labeled with the Biolegend TotalSeq™-B Human Universal Cocktail (CITEseq). This technology allowed for independent labeling of each cell line and single-cell analysis of the pooled seven cell lines and the pseudo-microenvironment. The data generated from the aforementioned experiments are available as part of an online tool, which allows users to define cell heterogeneity and generates count tables as an output. The tool provides the cell line derivation for each cell and cell annotations for the pseudo-microenvironment based on CITEseq data by an experienced immunologist. Additionally, we created a range of pseudo-tumor tissues using different ratios of the aforementioned cells embedded in matrigel. These tissues were analyzed using 10XGenomics (FFPE samples) and Curio Bioscience (fresh frozen samples) platforms for spatial transcriptomics, further expanding the scope of our benchmark experiments. The benchmark experiments we conducted provide a unique opportunity to evaluate the performance of bioinformatics tools for detecting and characterizing tumor heterogeneity at the single-cell level. Overall, our experiments provide a controlled and standardized environment for assessing the accuracy and robustness of bioinformatics tools for studying tumor heterogeneity at the single-cell level, which can ultimately lead to more precise and effective cancer diagnosis and treatment.

Keywords: single cell omics, benchmark, spatial transcriptomics, CITEseq

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34 An Elasto-Viscoplastic Constitutive Model for Unsaturated Soils: Numerical Implementation and Validation

Authors: Maria Lazari, Lorenzo Sanavia

Abstract:

Mechanics of unsaturated soils has been an active field of research in the last decades. Efficient constitutive models that take into account the partial saturation of soil are necessary to solve a number of engineering problems e.g. instability of slopes and cuts due to heavy rainfalls. A large number of constitutive models can now be found in the literature that considers fundamental issues associated with the unsaturated soil behaviour, like the volume change and shear strength behaviour with suction or saturation changes. Partially saturated soils may either expand or collapse upon wetting depending on the stress level, and it is also possible that a soil might experience a reversal in the volumetric behaviour during wetting. Shear strength of soils also changes dramatically with changes in the degree of saturation, and a related engineering problem is slope failures caused by rainfall. There are several states of the art reviews over the last years for studying the topic, usually providing a thorough discussion of the stress state, the advantages, and disadvantages of specific constitutive models as well as the latest developments in the area of unsaturated soil modelling. However, only a few studies focused on the coupling between partial saturation states and time effects on the behaviour of geomaterials. Rate dependency is experimentally observed in the mechanical response of granular materials, and a viscoplastic constitutive model is capable of reproducing creep and relaxation processes. Therefore, in this work an elasto-viscoplastic constitutive model for unsaturated soils is proposed and validated on the basis of experimental data. The model constitutes an extension of an existing elastoplastic strain-hardening constitutive model capable of capturing the behaviour of variably saturated soils, based on energy conjugated stress variables in the framework of superposed continua. The purpose was to develop a model able to deal with possible mechanical instabilities within a consistent energy framework. The model shares the same conceptual structure of the elastoplastic laws proposed to deal with bonded geomaterials subject to weathering or diagenesis and is capable of modelling several kinds of instabilities induced by the loss of hydraulic bonding contributions. The novelty of the proposed formulation is enhanced with the incorporation of density dependent stiffness and hardening coefficients in order to allow the modeling of the pycnotropy behaviour of granular materials with a single set of material constants. The model has been implemented in the commercial FE platform PLAXIS, widely used in Europe for advanced geotechnical design. The algorithmic strategies adopted for the stress-point algorithm had to be revised to take into account the different approach adopted by PLAXIS developers in the solution of the discrete non-linear equilibrium equations. An extensive comparison between models with a series of experimental data reported by different authors is presented to validate the model and illustrate the capability of the newly developed model. After the validation, the effectiveness of the viscoplastic model is displayed by numerical simulations of a partially saturated slope failure of the laboratory scale and the effect of viscosity and degree of saturation on slope’s stability is discussed.

Keywords: PLAXIS software, slope, unsaturated soils, Viscoplasticity

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33 Metabolic Changes during Reprogramming of Wheat and Triticale Microspores

Authors: Natalia Hordynska, Magdalena Szechynska-Hebda, Miroslaw Sobczak, Elzbieta Rozanska, Joanna Troczynska, Zofia Banaszak, Maria Wedzony

Abstract:

Albinism is a common problem encountered in wheat and triticale breeding programs, which require in vitro culture steps e.g. generation of doubled haploids via androgenesis process. Genetic factor is a major determinant of albinism, however, environmental conditions such as temperature and media composition influence the frequency of albino plant formation. Cold incubation of wheat and triticale spikes induced a switch from gametophytic to sporophytic development. Further, androgenic structures formed from anthers of the genotypes susceptible to androgenesis or treated with cold stress, had a pool of structurally primitive plastids, with small starch granules or swollen thylakoids. High temperature was a factor inducing andro-genesis of wheat and triticale, but at the same time, it was a factor favoring the formation of albino plants. In genotypes susceptible to albinism or after heat stress conditions, cells formed from anthers were vacuolated, and plastids were eliminated. Partial or complete loss of chlorophyll pigments and incomplete differentiation of chloroplast membranes result in formation of tissues or whole plant unable to perform photosynthesis. Indeed, susceptibility to the andro-genesis process was associated with an increase of total concentration of photosynthetic pigments in anthers, spikes and regenerated plants. The proper balance of the synthesis of various pigments, was the starting point for their proper incorporation into photosynthetic membranes. In contrast, genotypes resistant to the androgenesis process and those treated with heat, contained 100 times lower content of photosynthetic pigments. In particular, the synthesis of violaxanthin, zeaxanthin, lutein and chlorophyll b was limited. Furthermore, deregulation of starch and lipids synthesis, which led to the formation of very complex starch granules and an increased number of oleosomes, respectively, correlated with the reduction of the efficiency of androgenesis. The content of other sugars varied depending on the genotype and the type of stress. The highest content of various sugars was found for genotypes susceptible to andro-genesis, and highly reduced for genotypes resistant to androgenesis. The most important sugars seem to be glucose and fructose. They are involved in sugar sensing and signaling pathways, which affect the expression of various genes and regulate plant development. Sucrose, on the other hand, seems to have minor effect at each stage of the androgenesis. The sugar metabolism was related to metabolic activity of microspores. The genotypes susceptible to androgenesis process had much faster mitochondrium- and chloroplast-dependent energy conversion and higher heat production by tissues. Thus, the effectiveness of metabolic processes, their balance and the flexibility under the stress was a factor determining the direction of microspore development, and in the later stages of the androgenesis process, a factor supporting the induction of androgenic structures, chloroplast formation and the regeneration of green plants. The work was financed by Ministry of Agriculture and Rural Development within Program: ‘Biological Progress in Plant Production’, project no HOR.hn.802.15.2018.

Keywords: androgenesis, chloroplast, metabolism, temperature stress

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32 Isolation of Bacterial Species with Potential Capacity for Siloxane Removal in Biogas Upgrading

Authors: Ellana Boada, Eric Santos-Clotas, Alba Cabrera-Codony, Maria Martin, Lluis Baneras, Frederic Gich

Abstract:

Volatile methylsiloxanes (VMS) are a group of manmade silicone compounds widely used in household and industrial applications that end up on the biogas produced through the anaerobic digestion of organic matter in landfills and wastewater treatment plants. The presence of VMS during the biogas energy conversion can cause damage on the engines, reducing the efficiency of this renewable energy source. Non regenerative adsorption onto activated carbon is the most widely used technology to remove siloxanes from biogas, while new trends point out that biotechnology offers a low-cost and environmentally friendly alternative to conventional technologies. The first objective of this research was to enrich, isolate and identify bacterial species able to grow using siloxane molecules as a sole carbon source: anoxic wastewater sludge was used as initial inoculum in liquid anoxic enrichments, adding D4 (as representative siloxane compound) previously adsorbed on activated carbon. After several months of acclimatization, liquid enrichments were plated onto solid media containing D4 and thirty-four bacterial isolates were obtained. 16S rRNA gene sequencing allowed the identification of strains belonging to the following species: Ciceribacter lividus, Alicycliphilus denitrificans, Pseudomonas aeruginosa and Pseudomonas citronellolis which are described to be capable to degrade toxic volatile organic compounds. Kinetic assays with 8 representative strains revealed higher cell growth in the presence of D4 compared to the control. Our second objective was to characterize the community composition and diversity of the microbial community present in the enrichments and to elucidate whether the isolated strains were representative members of the community or not. DNA samples were extracted, the 16S rRNA gene was amplified (515F & 806R primer pair), and the microbiome analyzed from sequences obtained with a MiSeq PE250 platform. Results showed that the retrieved isolates only represented a minor fraction of the microorganisms present in the enrichment samples, which were represented by Alpha, Beta, and Gamma proteobacteria as dominant groups in the category class thus suggesting that other microbial species and/or consortia may be important for D4 biodegradation. These results highlight the need of additional protocols for the isolation of relevant D4 degraders. Currently, we are developing molecular tools targeting key genes involved in siloxane biodegradation to identify and quantify the capacity of the isolates to metabolize D4 in batch cultures supplied with a synthetic gas stream of air containing 60 mg m⁻³ of D4 together with other volatile organic compounds found in the biogas mixture (i.e. toluene, hexane and limonene). The isolates were used as inoculum in a biotrickling filter containing lava rocks and activated carbon to assess their capacity for siloxane removal. Preliminary results of biotrickling filter performance showed 35% of siloxane biodegradation in a contact time of 14 minutes, denoting that biological siloxane removal is a promising technology for biogas upgrading.

Keywords: bacterial cultivation, biogas upgrading, microbiome, siloxanes

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31 Impact of Ocean Acidification on Gene Expression Dynamics during Development of the Sea Urchin Species Heliocidaris erythrogramma

Authors: Hannah R. Devens, Phillip L. Davidson, Dione Deaker, Kathryn E. Smith, Gregory A. Wray, Maria Byrne

Abstract:

Marine invertebrate species with calcifying larvae are especially vulnerable to ocean acidification (OA) caused by rising atmospheric CO₂ levels. Acidic conditions can delay development, suppress metabolism, and decrease the availability of carbonate ions in the ocean environment for skeletogenesis. These stresses often result in increased larval mortality, which may lead to significant ecological consequences including alterations to the larval settlement, population distribution, and genetic connectivity. Importantly, many of these physiological and developmental effects are caused by genetic and molecular level changes. Although many studies have examined the effect of near-future oceanic pH levels on gene expression in marine invertebrates, little is known about the impact of OA on gene expression in a developmental context. Here, we performed mRNA-sequencing to investigate the impact of environmental acidity on gene expression across three developmental stages in the sea urchin Heliocidaris erythrogramma. We collected RNA from gastrula, early larva, and 1-day post-metamorphic juvenile sea urchins cultured at present-day and predicted future oceanic pH levels (pH 8.1 and 7.7, respectively). We assembled an annotated reference transcriptome encompassing development from egg to ten days post-metamorphosis by combining these data with datasets from two previous developmental transcriptomic studies of H. erythrogramma. Differential gene expression and time course analyses between pH conditions revealed significant alterations to developmental transcription that are potentially associated with pH stress. Consistent with previous investigations, genes involved in biomineralization and ion transport were significantly upregulated under acidic conditions. Differences in gene expression between the two pH conditions became more pronounced post-metamorphosis, suggesting a development-dependent effect of OA on gene expression. Furthermore, many differences in gene expression later in development appeared to be a result of broad downregulation at pH 7.7: of 539 genes differentially expressed at the juvenile stage, 519 of these were lower in the acidic condition. Time course comparisons between pH 8.1 and 7.7 samples also demonstrated over 500 genes were more lowly expressed in pH 7.7 samples throughout development. Of the genes exhibiting stage-dependent expression level changes, over 15% of these diverged from the expected temporal pattern of expression in the acidic condition. Through these analyses, we identify novel candidate genes involved in development, metabolism, and transcriptional regulation that are possibly affected by pH stress. Our results demonstrate that pH stress significantly alters gene expression dynamics throughout development. A large number of genes differentially expressed between pH conditions in juveniles relative to earlier stages may be attributed to the effects of acidity on transcriptional regulation, as a greater proportion of mRNA at this later stage has been nascent transcribed rather than maternally loaded. Also, the overall downregulation of many genes in the acidic condition suggests that OA-induced developmental delay manifests as suppressed mRNA expression, possibly from lower transcription rates or increased mRNA degradation in the acidic environment. Further studies will be necessary to determine in greater detail the extent of OA effects on early developing marine invertebrates.

Keywords: development, gene expression, ocean acidification, RNA-sequencing, sea urchins

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