Search results for: adipose derived stem cells

Authors: Blaga Alexandra Cristina, Kloetzer Lenuta, Bompa Amalia Stela, Galaction Anca Irina, Cascaval Dan

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Vitamin B9 is an important member of vitamins B group, being a growth factor, important for making genetic material as DNA and RNA, red blood cells, for building muscle tissues, especially during periods of infancy, adolescence and pregnancy. Its production by biosynthesis is based on the high metabolic potential of mutant Bacillus subtilis, due to a superior biodisponibility compared to that obtained by chemical pathways. Pertraction, defined as the extraction and transport through liquid membranes consists in the transfer of a solute between two aqueous phases of different pH-values, phases that are separated by a solvent layer of various sizes. The pertraction efficiency and selectivity could be significantly enhanced by adding a carrier in the liquid membrane, such as organophosphoric compounds, long chain amines or crown-ethers etc., the separation process being called facilitated pertraction. The aim of the work is to determine the impact of the presence of two extractants/carriers in the bulk liquid membrane, i.e. di(2-ethylhexyl) phosphoric acid (D2EHPA) and lauryltrialkylmetilamine (Amberlite LA2) on the transport kinetics of vitamin B9. The experiments have been carried out using two pertraction equipments for a free liquid membrane or bulk liquid membrane. One pertraction cell consists on a U-shaped glass pipe (used for the dichloromethane membrane) and the second one is an H-shaped glass pipe (used for h-heptane), having 45 mm inner diameter of the total volume of 450 mL, the volume of each compartment being of 150 mL. The aqueous solutions are independently mixed by means of double blade stirrers with 6 mm diameter and 3 mm height, having the rotation speed of 500 rpm. In order to reach high diffusional rates through the solvent layer, the organic phase has been mixed with a similar stirrer, at a similar rotation speed (500 rpm). The area of mass transfer surface, both for extraction and for reextraction, was of 1.59x10-³ m2. The study on facilitated pertraction with the mixture of two carriers, namely D2EHPA and Amberlite LA-2, dissolved in two solvents with different polarities: n-heptane and dichloromethane, indicated the possibility to obtain the synergic effect. The synergism has been analyzed by considering the vitamin initial and final mass flows, as well as the permeability factors through liquid membrane. The synergic effect has been observed at low D2EHPA concentrations and high Amberlite LA-2 concentrations, being more important for the low-polar solvent (n-heptane). The results suggest that the mechanism of synergic pertraction consists on the reaction between the organophosphoric carrier and vitamin B9 at the interface between the feed and membrane phases, while the aminic carrier enhances the hydrophobicity of this compound by solvation. However, the formation of this complex reduced the reextraction rate and, consequently, affects the synergism related to the final mass flows and permeability factor. For describing the influences of carriers concentrations on the synergistic coefficients, some equations have been proposed by taking into account the vitamin mass flows or permeability factors, with an average deviations between 4.85% and 10.73%.

Keywords: pertraction, synergism, vitamin B9, Amberlite LA-2, di(2-ethylhexyl) phosphoric acid

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Authors: B. Atika, S. Lehmann, E. Wimmer

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The defense strategy is very common in the insect world. Defensive substances play a wide variety of functions for beetles, such as repellents, toxicants, insecticides, and antimicrobics. Beetles react to predators, invaders, and parasitic microbes with the release of toxic and repellent substances. Defensive substances are directed against a large array of potential target organisms or may function for boiling bombardment or as surfactants. Usually, Coleoptera biosynthesize and store their defensive compounds in a complex secretory organ, known as odoriferous defensive stink glands. The red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae), uses these glands to produce antimicrobial p-benzoquinones and 1-alkenes. In the past, the morphology of stink gland has been studied in detail in tenebrionid beetles; however, very little is known about the genes that are involved in the production of gland secretion. In this study, we studied a subset of genes that are essential for the benzoquinone production in red flour beetle. In the first phase, we selected 74 potential candidate genes from a genome-wide RNA interference (RNAi) knockdown screen named 'iBeetle.' All these 74 candidate genes were functionally characterized by RNAi-mediated gene knockdown. Therefore, they were selected for a subsequent gas chromatography-mass spectrometry (GC-MS) analysis of secretion volatiles in respective RNAi knockdown glands. 33 of them were observed to alter the phenotype of stink gland. In the GC-MS analysis, 7 candidate genes were noted to display a strongly altered gland, in terms of secretion color and chemical composition, upon knockdown, showing their key role in the biosynthesis of gland secretion. Morphologically altered stink glands were found for odorant receptor and protein kinase superfamily. Subsequent GC-MS analysis of secretion volatiles revealed reduced benzoquinone levels in LIM domain, PDZ domain, PBP/GOBP family knockdowns and a complete lack of benzoquinones in the knockdown of sulfatase-modifying factor enzyme 1, sulfate transporter family. Based on stink gland transcriptome data, we analyzed the function of sulfatase-modifying factor enzyme 1 and sulfate transporter family via RNAi-mediated gene knockdowns, GC-MS, in situ hybridization, and enzymatic activity assays. Morphologically altered stink glands were noted in knockdown of both these genes. Furthermore, GC-MS analysis of secretion volatiles showed a complete lack of benzoquinones in the knockdown of these two genes. In situ hybridization showed that these two genes are expressed around the vesicle of certain subgroup of secretory stink gland cells. Enzymatic activity assays on stink gland tissue showed that these genes are involved in p-benzoquinone biosynthesis. These results suggest that sulfatase-modifying factor enzyme 1 and sulfate transporter family play a role specifically in benzoquinone biosynthesis in red flour beetles.

Keywords: Red Flour Beetle, defensive stink gland, benzoquinones, sulfate transporter, sulfatase-modifying factor enzyme 1

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Authors: Roberta Mugellesi Dow

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As the climate crisis becomes unignorable, it is imperative that new services are developed addressing not only the needs of customers but also taking into account its impact on the environment. The Telecommunication and Integrated Application (TIA) Directorate of ESA is supporting the green transition with particular attention to the sustainable mobility.“Accelerating the shift to sustainable and smart mobility” is at the core of the European Green Deal strategy, which seeks a 90% reduction in related emissions by 2050 . Transforming the way that people and goods move is essential to increasing mobility while decreasing environmental impact, and transport must be considered holistically to produce a shared vision of green intermodal mobility. The use of space technologies, integrated with terrestrial technologies, is an enabler of smarter traffic management and increased transport efficiency for automated and connected multimodal mobility. Satellite connectivity, including future 5G networks, and digital technologies such as Digital Twin, AI, Machine Learning, and cloud-based applications are key enablers of sustainable mobility.SatCom is essential to ensure that connectivity is ubiquitously available, even in remote and rural areas, or in case of a failure, by the convergence of terrestrial and SatCom connectivity networks, This is especially crucial when there are risks of network failures or cyber-attacks targeting terrestrial communication. SatCom ensures communication network robustness and resilience. The combination of terrestrial and satellite communication networks is making possible intelligent and ubiquitous V2X systems and PNT services with significantly enhanced reliability and security, hyper-fast wireless access, as well as much seamless communication coverage. SatNav is essential in providing accurate tracking and tracing capabilities for automated vehicles and in guiding them to target locations. SatNav can also enable location-based services like car sharing applications, parking assistance, and fare payment. In addition to GNSS receivers, wireless connections, radar, lidar, and other installed sensors can enable automated vehicles to monitor surroundings, to ‘talk to each other’ and with infrastructure in real-time, and to respond to changes instantaneously. SatEO can be used to provide the maps required by the traffic management, as well as evaluate the conditions on the ground, assess changes and provide key data for monitoring and forecasting air pollution and other important parameters. Earth Observation derived data are used to provide meteorological information such as wind speed and direction, humidity, and others that must be considered into models contributing to traffic management services. The paper will provide examples of services and applications that have been developed aiming to identify innovative solutions and new business models that are allowed by new digital technologies engaging space and non space ecosystem together to deliver value and providing innovative, greener solutions in the mobility sector. Examples include Connected Autonomous Vehicles, electric vehicles, green logistics, and others. For the technologies relevant are the hybrid satcom and 5G providing ubiquitous coverage, IoT integration with non space technologies, as well as navigation, PNT technology, and other space data.

Keywords: sustainability, connectivity, mobility, satellites

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Authors: Jim O'brien

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Contemporary global representation and consumption of La Liga across a plethora of media platform outlets has resulted in significant implications for the historical, political and cultural developments which shaped the development of Spanish club football. This has established and reinforced a hierarchy of a small number of teams belonging to or aspiring to belong to a cluster of global elite clubs seeking to imitate the blueprint of the English Premier League in respect of corporate branding and marketing in order to secure a global fan base through success and exposure in La Liga itself and through the Champions League. The synthesis between globalization, global sport and the status of high profile clubs has created radical change within the folkloric iconography of Spanish football. The main focus of this paper is to critically evaluate the consequences of globalization on the rich tapestry at the core of the game’s distinctive history in Spain. The seminal debate underpinning the study considers whether the divergent aspects of globalization have acted as a malevolent force, eroding tradition, causing financial meltdown and reducing much of the fabric of club football to the status of by standers, or have promoted a renaissance of these traditions, securing their legacies through new fans and audiences. The study draws on extensive sources on the history, politics and culture of Spanish football, in both English and Spanish. It also uses primary and archive material derived from interviews and fieldwork undertaken with scholars, media professionals and club representatives in Spain. The paper has four main themes. Firstly, it contextualizes the key historical, political and cultural forces which shaped the landscape of Spanish football from the late nineteenth century. The seminal notions of region, locality and cultural divergence are pivotal to this discourse. The study then considers the relationship between football, ethnicity and identity as a barometer of continuity and change, suggesting that tradition is being reinvented and re-framed to reflect the shifting demographic and societal patterns within the Spanish state. Following on from this, consideration is given to the paradoxical function of ‘El Clasico’ and the dominant duopoly of the FC Barcelona – Real Madrid axis in both eroding tradition in the global nexus of football’s commodification and in protecting historic political rivalries. To most global consumers of La Liga, the mega- spectacle and hyperbole of ‘El Clasico’ is the essence of Spanish football, with cultural misrepresentation and distortion catapulting the event to the global media audience. Finally, the paper examines La Liga as a sporting phenomenon in which elite clubs, cult managers and galacticos serve as commodities on the altar of mass consumption in football’s global entertainment matrix. These processes accentuate a homogenous mosaic of cultural conformity which obscures local, regional and national identities and paradoxically fuses the global with the local to maintain the distinctive hue of La Liga, as witnessed by the extraordinary successes of Athletico Madrid and FC Eibar in recent seasons.

Keywords: Spanish football, globalization, cultural identity, tradition, folklore

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Authors: Rajwanlop Kumpoopong, Sukit Yindeesuk, Pornchai Silarom

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Modeling cracks in concrete is complicated by its strain-softening behavior which requires the use of sophisticated energy criteria of fracture mechanics to assure stable and convergent solutions in the finite-element (FE) analysis particularly for relatively large structures. However, for small-scale structures such as beams and slabs, a simpler approach relies on retaining some shear stiffness in the cracking plane has been adopted in literature to model the strain-softening behavior of concrete under monotonically increased loading. According to the shear retaining approach, each element is assumed to be an isotropic material prior to cracking of concrete. Once an element is cracked, the isotropic element is replaced with an orthotropic element in which the new orthotropic stiffness matrix is formulated with respect to the crack orientation. The shear transfer factor of 0.5 is used in parallel to the crack plane. The shear retaining approach is adopted in this research to model cracks in RC bridge deck with some modifications to take into account the effect of repetitive moving truck wheel loads as they cause fatigue cracking of concrete. First modification is the introduction of fatigue tests of concrete and reinforcing steel and the Palmgren-Miner linear criterion of cumulative damage in the conventional FE analysis. For a certain loading, the number of cycles to failure of each concrete or RC element can be calculated from the fatigue or S-N curves of concrete and reinforcing steel. The elements with the minimum number of cycles to failure are the failed elements. For the elements that do not fail, the damage is accumulated according to Palmgren-Miner linear criterion of cumulative damage. The stiffness of the failed element is modified and the procedure is repeated until the deck slab fails. The total number of load cycles to failure of the deck slab can then be obtained from which the S-N curve of the deck slab can be simulated. Second modification is the modification in shear transfer factor. Moving loading causes continuous rubbing of crack interfaces which greatly reduces shear transfer mechanism. It is therefore conservatively assumed in this study that the analysis is conducted with shear transfer factor of zero for the case of moving loading. A customized FE program has been developed using the MATLAB software to accomodate such modifications. The developed procedure has been validated with the fatigue test of the 1/6.6-scale AASHTO bridge deck under the applications of both fixed-point repetitive loading and moving loading presented in the literature. Results are in good agreement both experimental vs. simulated S-N curves and observed vs. simulated crack patterns. Significant contribution of the developed procedure is a series of S-N relations which can now be simulated at any desired levels of cracking in addition to the experimentally derived S-N relation at the failure of the deck slab. This permits the systematic investigation of crack propagation or deterioration of RC bridge deck which is appeared to be useful information for highway agencies to prolong the life of their bridge decks.

Keywords: bridge deck, cracking, deterioration, fatigue, finite-element, moving truck, reinforced concrete

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Authors: LouAnne Boyd

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From the perspective of self-advocates, the biggest unaddressed problem is not the symptoms of an autism spectrum diagnosis but the social stigma that accompanies autism. This societal perspective is in contrast to the focus on the majority of interventions. Autism interventions, and consequently, most innovative technologies for autism, aim to improve deficits that occur within the person. For example, the most common Human-Computer Interaction research projects in assistive technology for autism target social skills from a normative perspective. The premise of the autism technologies is that difficulties occur inside the body, hence, the medical model focuses on ways to improve the ailment within the person. However, other technological approaches to support people with autism do exist. In the realm of Human Computer Interaction, there are other modes of research that provide critique of the medical model. For example, critical design, whose intended audience is industry or other HCI researchers, provides products that are the opposite of interventionist work to bring attention to the misalignment between the lived experience and the societal perception of autism. For example, parodies of interventionist work exist to provoke change, such as a recent project called Facesavr, a face covering that helps allistic adults be more independent in their emotional processing. Additionally, from a critical disability studies’ perspective, assistive technologies perpetuate harmful normalizing behaviors. However, these critical approaches can feel far from the frontline in terms of taking direct action to positively impact end users. From a critical yet more pragmatic perspective, projects such as Counterventions lists ways to reduce the likelihood of perpetuating ableism in interventionist’s work by reflectively analyzing a series of evolving assistive technology projects through a societal lens, thus leveraging the momentum of the evolving ecology of technologies for autism. Therefore, all current paradigms fall short of addressing the largest need—the negative impact of social stigma. The current work introduces a new paradigm for technologies for autism, borrowing from a paradigm introduced two decades ago around changing the narrative related to eating disorders. It is the shift from reprimanding poor habits to celebrating positive aspects of eating. This work repurposes Celebratory Technology for Neurodiversity and intended to reduce social stigma by targeting for the public at large. This presentation will review how requirements were derived from current research on autism social stigma as well as design sessions with autistic adults. Congruence between these two sources revealed three key design implications for technology: provide awareness of the autistic experience; generate acceptance of the neurodivergence; cultivate an appreciation for talents and accomplishments of neurodivergent people. The current pilot work in Celebratory Technology offers a new paradigm for supporting autism by shifting the burden of change from the person with autism to address changing society’s biases at large. Shifting the focus of research outside of the autistic body creates a new space for a design that extends beyond the bodies of a few and calls on all to embrace humanity as a whole.

Keywords: neurodiversity, social stigma, accessibility, inclusion, celebratory technology

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Authors: Rosa Nadine Danenberg

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In recent years, bottom-up urban development has started growing as an alternative to conventional top-down planning. In large proportions, citizens and communities initiate small-scale interventions; suddenly seeming to form a trend. As a result, more and more cities are witnessing not only the growth of but also an interest in these initiatives, as they bear the potential to reshape urban spaces. Such alternative city-making efforts cause new dynamics in urban governance, with inevitable consequences for the controlled city planning and its administration. The emergence of enabling relationships between top-down and bottom-up actors signals an increasingly common urban practice. Various case studies show that an enabling relationship is possible, yet, how it can be optimally realized stays rather underexamined. Therefore, the seemingly growing worldwide phenomenon of ‘municipal bottom-up urban development’ necessitates an adequate governance structure. As such, the aim of this research is to contribute knowledge to how municipalities can enable citizen-led urban initiatives from a governance innovation perspective. Empirical case-study research in Stockholm and Istanbul, derived from interviews with founders of four citizen-led urban initiatives and one municipal representative in each city, provided valuable insights to possibilities and constraints for enabling practices. On the one hand, diverging outcomes emphasize the extreme oppositional features of both cases (Stockholm and Istanbul). Firstly, both cities’ characteristics are drastically different. Secondly, the ideologies and motifs for the initiatives to emerge vary widely. Thirdly, the major constraints for citizen-led urban initiatives to relate to the municipality are considerably different. Two types of municipality’s organizational structures produce different underlying mechanisms which demonstrate the constraints. The first municipal organizational structure is steered by bureaucracy (Stockholm). It produces an administrative division that brings up constraints such as the lack of responsibility, transparency and continuity by municipal representatives. The second structure is dominated by municipal politics and governmental hierarchy (Istanbul). It produces informality, lack of transparency and a fragmented civil society. In order to cope with the constraints produced by both types of organizational structures, the initiatives have adjusted their organization to the municipality’s underlying structures. On the other hand, this paper has in fact also come to a rather unifying conclusion. Interestingly, the suggested possibilities for an enabling relationship underline converging new urban governance arrangements. This could imply that for the two varying types of municipality’s organizational structures there is an accurate governance structure. Namely, the combination of a neighborhood council with a municipal guide, with allowance for the initiatives to adopt a politicizing attitude is found as coinciding. Especially its combination appears key to redeem varying constraints. A municipal guide steers the initiatives through bureaucratic struggles, is supported by coproduction methods, while it balances out municipal politics. Next, a neighborhood council, that is politically neutral and run by local citizens, can function as an umbrella for citizen-led urban initiatives. What is crucial is that it should cater for a more entangled relationship between municipalities and initiatives with enhanced involvement of the initiatives in decision-making processes and limited involvement of prevailing constraints pointed out in this research.

Keywords: bottom-up urban development, governance innovation, Istanbul, Stockholm

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Authors: Ramanpreet, Gursatej Gandhi

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Background: Dependence on electromagnetic radiations involved in communication and information technologies has incredibly increased in the personal and professional world. Among the numerous radiations, sources are fixed site transmitters, mobile phone base stations, and power lines beside indoor devices like cordless phones, WiFi, Bluetooth, TV, radio, microwave ovens, etc. Rather there is the continuous emittance of radiofrequency radiations (RFR) even to those not using the devices from mobile phone base stations. The consistent and widespread usage of wireless devices has build-up electromagnetic fields everywhere. In fact, the radiofrequency electromagnetic field (RF-EMF) has insidiously become a part of the environment and like any contaminant may pose to be health-hazardous requiring assessment. Materials and Methods: In the present study, cytogenetic damage was assessed using the Buccal Micronucleus Cytome (BMCyt) assay as a function of radiation exposure after Institutional Ethics Committee clearance of the study and written voluntary informed consent from the participants. On a pre-designed questionnaire, general information lifestyle patterns (diet, physical activity, smoking, drinking, use of mobile phones, internet, Wi-Fi usage, etc.) genetic, reproductive (pedigrees) and medical histories were recorded. For this, 24 hour-personal exposimeter measurements (PEM) were recorded for unrelated 60 healthy adults (40 cases residing in the vicinity of mobile phone base stations since their installation and 20 controls residing in areas with no base stations). The personal exposimeter collects information from all the sources generating EMF (TETRA, GSM, UMTS, DECT, and WLAN) as total RF-EMF uplink and downlink. Findings: The cases (n=40; 23-90 years) and the controls (n=20; 19-65 years) matched for alcohol drinking, smoking habits, and mobile and cordless phone usage. The PEM in cases (149.28 ± 8.98 mV/m) revealed significantly higher (p=0.000) electric field strength compared to the recorded value (80.40 ± 0.30 mV/m) in controls. The GSM 900 uplink (p=0.000), GSM 1800 downlink (p=0.000),UMTS (both uplink; p=0.013 and downlink; p=0.001) and DECT (p=0.000) electric field strength were significantly elevated in the cases as compared to controls. The electric field strength in the cases was significantly from GSM1800 (52.26 ± 4.49mV/m) followed by GSM900 (45.69 ± 4.98mV/m), UMTS (25.03 ± 3.33mV/m), DECT (18.02 ± 2.14mV/m) and was least from WLAN (8.26 ± 2.35mV/m). The higher significantly (p=0.000) increased exposure to the cases was from GSM (97.96 ± 6.97mV/m) in comparison to UMTS, DECT, and WLAN. The frequencies of micronuclei (1.86X, p=0.007), nuclear buds (2.95X, p=0.002) and cell death parameter (condensed chromatin cells) were significantly (1.75X, p=0.007) elevated in cases compared to that in controls probably as a function of radiofrequency radiation exposure. Conclusion: In the absence of other exposure(s), any cytogenetic damage if unrepaired is a cause of concern as it can cause malignancy. Larger sample size with the clinical assessment will prove more insightful of such an effect.

Keywords: Buccal micronucleus cytome assay, cytogenetic damage, electric field strength, personal exposimeter

Procedia PDF Downloads 139

Authors: C. Fernandez-Plaza, I. Abad, E. Diaz, I. Diaz

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Births occurring before the 37th week of gestation are considered preterm births. A threat of preterm is defined as the beginning of regular uterine contractions, dilation and cervical effacement between 23 and 36 gestation weeks. To author's best knowledge, the factors that determine the beginning of the birth are not completely defined yet. In particular, the incidence of sleep habits on preterm births is weekly studied. The aim of this study is to develop a model to predict the factors affecting premature delivery on pregnancy, based on the above potential risk factors, including those derived from sleep habits and light exposure at night (introduced as 12 variables obtained by a telephone survey using two questionnaires previously used by other authors). Thus, three groups of variables were included in the study (maternal, fetal and sleep habits). The study was approved by Research Ethics Committee of the Principado of Asturias (Spain). An observational, retrospective and descriptive study was performed with 481 births between January 1, 2015 and May 10, 2016 in the University Central Hospital of Asturias (Spain). A statistical analysis using SPSS was carried out to compare qualitative and quantitative variables between preterm and term delivery. Chi-square test qualitative variable and t-test for quantitative variables were applied. Statistically significant differences (p < 0.05) between preterm vs. term births were found for primiparity, multi-parity, kind of conception, place of residence or premature rupture of membranes and interruption during nights. In addition to the statistical analysis, machine learning methods to look for a prediction model were tested. In particular, tree based models were applied as the trade-off between performance and interpretability is especially suitable for this study. C5.0, recursive partitioning, random forest and tree bag models were analysed using caret R-package. Cross validation with 10-folds and parameter tuning to optimize the methods were applied. In addition, different noise reduction methods were applied to the initial data using NoiseFiltersR package. The best performance was obtained by C5.0 method with Accuracy 0.91, Sensitivity 0.93, Specificity 0.89 and Precision 0.91. Some well known preterm birth factors were identified: Cervix Dilation, maternal BMI, Premature rupture of membranes or nuchal translucency analysis in the first trimester. The model also identifies other new factors related to sleep habits such as light through window, bedtime on working days, usage of electronic devices before sleeping from Mondays to Fridays or change of sleeping habits reflected in the number of hours, in the depth of sleep or in the lighting of the room. IF dilation < = 2.95 AND usage of electronic devices before sleeping from Mondays to Friday = YES and change of sleeping habits = YES, then preterm is one of the predicting rules obtained by C5.0. In this work a model for predicting preterm births is developed. It is based on machine learning together with noise reduction techniques. The method maximizing the performance is the one selected. This model shows the influence of variables related to sleep habits in preterm prediction.

Keywords: machine learning, noise reduction, preterm birth, sleep habit

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Authors: D. Malouch, M. Berchel, C. Dreanno, S. Stachowski-Haberkorn, P-A. Jaffres

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Biofouling is a complex natural phenomenon that involves biological, physical and chemical properties related to the environment, the submerged surface and the living organisms involved. Bio-colonization of artificial structures can cause various economic and environmental impacts. The increase in costs associated with the over-consumption of fuel from biocolonized vessels has been widely studied. Measurement drifts from submerged sensors, as well as obstructions in heat exchangers, and deterioration of offshore structures are major difficulties that industries are dealing with. Therefore, surfaces that inhibit biocolonization are required in different areas (water treatment, marine paints, etc.) and many efforts have been devoted to produce efficient and eco-compatible antifouling agents. The different steps of surface fouling are widely described in literature. Studying the biofilm and its stages provides a better understanding of how to elaborate more efficient antifouling strategies. Several approaches are currently applied, such as the use of biocide anti-fouling paint (mainly with copper derivatives) and super-hydrophobic coatings. While these two processes are proving to be the most effective, they are not entirely satisfactory, especially in a context of a changing legislation. Nowadays, the challenge is to prevent biofouling with non-biocide compounds, offering a cost effective solution, but with no toxic effects on marine organisms. Since the micro-fouling phase plays an important role in the regulation of the following steps of biofilm formation, it is desired to reduce or delate biofouling of a given surface by inhibiting the micro-fouling at its early stages. In our recent works, we reported that some amphiphilic compounds exhibited bacteriostatic or bactericidal properties at a concentration that did not affect mammalian eukaryotic cells. These remarkable properties invited us to assess this type of bio-inspired phospholipids to prevent the colonization of surfaces by marine bacteria. Of note, other studies reported that amphiphilic compounds interacted with bacteria leading to a reduction of their development. An amphiphilic compound is a molecule consisting of a hydrophobic domain and a polar head (ionic or non-ionic). These compounds appear to have interesting antifouling properties: some ionic compounds have shown antimicrobial activity, and zwitterions can reduce nonspecific adsorption of proteins. Herein, we investigate the potential of amphiphilic compounds as inhibitors of bacterial growth and marine biofilm formation. The aim of this study is to compare the efficacy of four synthetic phospholipids that features a cationic charge or a zwitterionic polar-head group to prevent microfouling with marine bacteria. Toxicity of these compounds was also studied in order to identify the most promising compounds that inhibit biofilm development and show low cytotoxicity on two links representative of coastal marine food webs: phytoplankton and oyster larvae.

Keywords: amphiphilic phospholipids, biofilm, marine fouling, non-toxique assays

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Authors: Aura Maria Lopera Echavarria, Angela Maria Lema Perez, Daniela Medrano David, Pedronel Araque Marin, Marta Elena Londoño Lopez

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Bone regeneration is the process by which the formation of new bone is stimulated. Bone fractures can originate at any time due to trauma, infections, tumors, congenital malformations or skeletal diseases. Currently there are different strategies to treat bone defects that in some cases, regeneration does not occur on its own. That is why they are treated with bone substitutes, which provide a necessary environment for the cells to synthesize new bone. The Demineralized Bone Matrix (DBM) is widely used as a bone implant due to its good properties, such as osteoinduction and bioactivity. However, the use of DBM is limited, because its presentation is powder, which is difficult to implant with precision and is susceptible to migrating to other sites through blood flow. That is why the DBM is commonly incorporated into a variety of vehicles or carriers. The objective of this project is to evaluate the bioactive and confinement properties of a bone substitute based on demineralized bone matrix (DBM). Also, structural and morphological properties were evaluated. Bone substitute was obtained from EIA Biomaterials Laboratory of EIA University and the DBM was facilitated by Tissue Bank Foundation. Morphological and structural properties were evaluated by scanning electron microscopy (SEM), X-ray diffraction (DRX) and Fourier transform infrared spectroscopy with total attenuated reflection (FTIR-ATR). Water absorption capacity and degradation were also evaluated during three months. The cytotoxicity was evaluated by the MTT test. The bioactivity of the bone substitute was evaluated through immersion of the samples in simulated body fluid during four weeks. Confinement tests were performed on tibial fragments of a human donor with bone defects of determined size, to ensure that the substitute remains in the defect despite the continuous flow of fluid. According of the knowledge of the authors, the methodology for evaluating samples in a confined environment has not been evaluated before in real human bones. The morphology of the samples showed irregular surface and presented some porosity. DRX confirmed a semi-crystalline structure. The FTIR-ATR determined the organic and inorganic phase of the sample. The degradation and absorption measurements stablished a loss of 3% and 150% in one month respectively. The MTT showed that the system is not cytotoxic. Apatite clusters formed from the first week were visualized by SEM and confirmed by EDS. These calcium phosphates are necessary to stimulate bone regeneration and thanks to the porosity of the developed material, osteinduction and osteoconduction are possible. The results of the in vitro evaluation of the confinement of the material showed that the migration of the bone filling to other sites is negligible, although the samples were subjected to the passage of simulated body fluid. The bone substitute, putty type, showed stability, is bioactive, non-cytotoxic and has handling properties for specialists at the time of implantation. The obtained system allows to maintain the osteoinductive properties of DBM and it can fill completely fractures in any way; however, it does not provide a structural support, that is, it should only be used to treat fractures without requiring a mechanical load.

Keywords: bone regeneration, cytotoxicity, demineralized bone matrix, hydrogel

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Authors: A. F. C. Nassar, D. K. Tessler, L. Okuda, C. Del Fava, D. P. Chiebao, A. H. C. N. Romaldini, A. P. Alvim, M. J. Sanchez-Vazquez, M. S. Rosa, J. C. Pompei, R. Harakava, M. C. S. Araujo, G. H. F. Marques, E. M. Pituco

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Glanders is a zoonotic disease of Equidae caused by the bacterium Burkholderia mallei presented in acute or chronic clinical forms with inflammatory nodules in the respiratory tract, lymphangitis and caseous lymph nodes. There is not a treatment with veterinary drugs to this life-threatening disease; thus, its occurrence must be notified to official animal health services and any infected animal must be eliminated. This study aims to detect B. mallei from horses euthanized in outbreaks of glanders in Brazil, providing a better understanding of the bacterial characteristics and determine a proper protocol for isolation. The work was carried out with the collaboration of the Ministry of Agriculture and the Sao Paulo State Animal Health Department, while its procedures were approved by the Committee of Ethics in Animal Experimentation from the Instituto Biologico (CETEA n°156/2017). To the present time, 16 horses from farms with outbreaks of glanders detected by complement fixation test (CFT) serology method were analyzed. During the necropsy, samples of possibly affected organs (lymph nodes, lungs, heart, liver, spleen, kidneys and trachea) were collected for bacterial isolation, molecular tests and pathology. Isolation was performed using two enriched mediums, a potato infusion agar with 5% sheep blood, 4% glycerol and antibiotics (penicilin100U/ mL), and another with the same ingredients except the antibiotic. A PCR protocol was modified for this study using primers design to identify a region of the Flip gen of B. mallei. Thru isolation, 12.5% (2/16) animals were confirmed positive using only the enriched medium with antibiotic and confirmed by PCR: from mediastinal and submandibular lymph nodes and lungs in one animal and from mediastinal lymph node in the other. The detection of the bacterium using PCR showed positivity of 100% (16/16) horses from 144 samples of organs. Pathology macroscopic lesions observed were catarrhal nasal discharge, fetlock ulcers, emaciation, lymphangitis in limbs, suppurative lymphangitis, lymph node enlargement, star shaped liver, and spleen scars, adherence of the renal capsule, pulmonary hemorrhage, and miliary nodules. Microscopic lesions were suppurative bronchopneumonia with microabscesses and Langhans giant cells in lungs; lymph nodes with abscesses and intense lymphoid reaction; hemosiderosis and abscesses in spleen. Positive samples on PCR will be sequenced later and analyzed comparing with previous records in the literature. A throughout description of the recent acute cases of glanders occurring in Brazil and characterization of the bacterium related will contribute to advances in the knowledge of the pathogenicity, clinical symptoms, and epidemiology of this zoonotic disease. Acknowledgment: This project is sponsored by FAPESP.

Keywords: equines, bacterial isolation, zoonosis, PCR, pathology

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Authors: Alfredo Fortunato, Carmelofrancesco Origlia, Sara Laurita, Rossella Nicoletti

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In the post-pandemic recovery phase of tourism, the role of a Destination Management Organization (DMO) as a coordinated management system of all the elements that make up a destination (attractions, access, marketing, human resources, brand, pricing, etc.) is also becoming relevant for local territories. The objective of a DMO is to maximize the visitor's perception of value and quality while ensuring the competitiveness and sustainability of the destination, as well as the long-term preservation of its natural and cultural assets, and to catalyze benefits for the local economy and residents. In carrying out the multiple functions to which it is called, the DMO can leverage a collective intelligence that comes from the ability to pool information, explicit and tacit knowledge, and relationships of the various stakeholders: policymakers, public managers and officials, entrepreneurs in the tourism supply chain, researchers, data journalists, schools, associations and committees, citizens, etc. The DMO potentially has at its disposal large volumes of data and many of them at low cost, that need to be properly processed to produce value. Based on these assumptions, the paper presents a conceptual framework for building an information system to support the DMO in the intelligent management of a tourist destination tested in an area of southern Italy. The approach adopted is data-informed and consists of four phases: (1) formulation of the knowledge problem (analysis of policy documents and industry reports; focus groups and co-design with stakeholders; definition of information needs and key questions); (2) research and metadatation of relevant sources (reconnaissance of official sources, administrative archives and internal DMO sources); (3) gap analysis and identification of unconventional information sources (evaluation of traditional sources with respect to the level of consistency with information needs, the freshness of information and granularity of data; enrichment of the information base by identifying and studying web sources such as Wikipedia, Google Trends, Booking.com, Tripadvisor, websites of accommodation facilities and online newspapers); (4) definition of the set of indicators and construction of the information base (specific definition of indicators and procedures for data acquisition, transformation, and analysis). The framework derived consists of 6 thematic areas (accommodation supply, cultural heritage, flows, value, sustainability, and enabling factors), each of which is divided into three domains that gather a specific information need to be represented by a scheme of questions to be answered through the analysis of available indicators. The framework is characterized by a high degree of flexibility in the European context, given that it can be customized for each destination by adapting the part related to internal sources. Application to the case study led to the creation of a decision support system that allows: •integration of data from heterogeneous sources, including through the execution of automated web crawling procedures for data ingestion of social and web information; •reading and interpretation of data and metadata through guided navigation paths in the key of digital story-telling; •implementation of complex analysis capabilities through the use of data mining algorithms such as for the prediction of tourist flows.

Keywords: collective intelligence, data framework, destination management, smart tourism

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Authors: Leonie Bradfield, Stephen Fityus, John Simmons

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The shearing behavior of current and planned coal mine spoil dumps up to 400m in height is studied using large-sample-high-stress direct shear tests performed on a range of spoils common to the coalfields of Eastern Australia. The motivation for the study is to address industry concerns that some constructed spoil dump heights ( > 350m) are exceeding the scale ( ≤ 120m) for which reliable design information exists, and because modern geotechnical laboratories are not equipped to test representative spoil specimens at field-scale stresses. For more than two decades, shear strength estimation for spoil dumps has been based on either infrequent, very small-scale tests where oversize particles are scalped to comply with device specimen size capacity such that the influence of prototype-sized particles on shear strength is not captured; or on published guidelines that provide linear shear strength envelopes derived from small-scale test data and verified in practice by slope performance of dumps up to 120m in height. To date, these published guidelines appear to have been reliable. However, in the field of rockfill dam design there is a broad acceptance of a curvilinear shear strength envelope, and if this is applicable to coal mine spoils, then these industry-accepted guidelines may overestimate the strength and stability of dumps at higher stress levels. The pressing need to rationally define the shearing behavior of more representative spoil specimens at field-scale stresses led to the successful design, construction and operation of a large direct shear machine (LDSM) and its subsequent application to provide reliable design information for current and planned very-high dumps. The LDSM can test at a much larger scale, in terms of combined specimen size (720mm x 720mm x 600mm) and stress (σn up to 4.6MPa), than has ever previously been achieved using a direct shear machine for geotechnical testing of rockfill. The results of an extensive LDSM testing program on a wide range of coal-mine spoils are compared to a published framework that widely accepted by the Australian coal mining industry as the standard for shear strength characterization of mine spoil. A critical outcome is that the LDSM data highlights several non-compliant spoils, and stress-dependent shearing behavior, for which the correct application of the published framework will not provide reliable shear strength parameters for design. Shear strength envelopes developed from the LDSM data are also compared with dam engineering knowledge, where failure envelopes of rockfills are curved in a concave-down manner. The LDSM data indicates that shear strength envelopes for coal-mine spoils abundant with rock fragments are not in fact curved and that the shape of the failure envelope is ultimately determined by the strength of rock fragments. Curvilinear failure envelopes were found to be appropriate for soil-like spoils containing minor or no rock fragments, or hard-soil aggregates.

Keywords: coal mine, direct shear test, high dump, large scale, mine spoil, shear strength, spoil dump

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Authors: Sevelina Ndlovu

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Financial Technology (fintech) advancement is recognised as one of the most transformational innovations in the financial industry. Fintech has given rise to internet-only digital banking, a novel financial technology advancement, and innovation that allows banking services through internet applications with no need for physical branches. This technology is becoming a new banking normal among consumers for its ubiquitous and real-time access advantages. There is evident switching and migration from traditional banking towards these fintech facilities, which could possibly pose a systemic risk if not properly understood and monitored. Fintech advancement has also brought about the emergence and escalation of financial technology consumption themes such as trust, security, perceived risk, and sustainability within the banking industry, themes scarcely covered in existing theoretic literature. To that end, the objective of this research is to investigate factors that determine fintech adoption and propose an integrated adoption model. This study aims to establish what the significant drivers of adoption are and develop a conceptual model that integrates technological, behavioral, and environmental constructs by extending the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2). It proposes integrating constructs that influence financial consumption themes such as trust, perceived risk, security, financial incentives, micro-investing opportunities, and environmental consciousness to determine the impact of these factors on the adoption and intention to use digital banking apps. The main advantage of this conceptual model is the consolidation of a greater number of predictor variables that can provide a fuller explanation of the consumer's adoption of digital banking Apps. Moderating variables of age, gender, and income are incorporated. To the best of author’s knowledge, this study is the first that extends the UTAUT2 model with this combination of constructs to investigate user’s intention to adopt internet-only digital banking apps in the UK context. By investigating factors that are not included in the existing theories but are highly pertinent to the adoption of internet-only banking services, this research adds to existing knowledge and extends the generalisability of the UTAUT2 in a financial services adoption context. This is something that fills a gap in knowledge, as highlighted to needing further research on UTAUT2 after reviewing the theory in 2016 from its original version of 2003. To achieve the objectives of this study, this research assumes a quantitative research approach to empirically test the hypotheses derived from existing literature and pilot studies to give statistical support to generalise the research findings for further possible applications in theory and practice. This research is explanatory or casual in nature and uses cross-section primary data collected through a survey method. Convenient and purposive sampling using structured self-administered online questionnaires is used for data collection. The proposed model is tested using Structural Equation Modelling (SEM), and the analysis of primary data collected through an online survey is processed using Smart PLS software with a sample size of 386 digital bank users. The results are expected to establish if there are significant relationships between the dependent and independent variables and establish what the most influencing factors are.

Keywords: banking applications, digital banking, financial technology, technology adoption, UTAUT2

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Authors: Francesca Fermi, Paola Astegiano, Angelo Martino, Stephanie Heitel, Michael Krail

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In order to achieve the targeted emission reductions for the decarbonisation of the European economy by 2050, fundamental contributions are required from both energy and transport sectors. The objective of this paper is to analyse the impacts of a largescale diffusion of e-vehicles, either battery-based or fuel cells, together with the implementation of transport policies aiming at decreasing the use of motorised private modes in order to achieve greenhouse gas emission reduction goals, in the context of a future high share of renewable energy. The analysis of the impacts and challenges of future scenarios on transport sector is performed with the ASTRA (ASsessment of TRAnsport Strategies) model. ASTRA is a strategic system-dynamic model at European scale (EU28 countries, Switzerland and Norway), consisting of different sub-modules related to specific aspects: the transport system (e.g. passenger trips, tonnes moved), the vehicle fleet (composition and evolution of technologies), the demographic system, the economic system, the environmental system (energy consumption, emissions). A key feature of ASTRA is that the modules are linked together: changes in one system are transmitted to other systems and can feed-back to the original source of variation. Thanks to its multidimensional structure, ASTRA is capable to simulate a wide range of impacts stemming from the application of transport policy measures: the model addresses direct impacts as well as second-level and third-level impacts. The simulation of the different scenarios is performed within the REFLEX project, where the ASTRA model is employed in combination with several energy models in a comprehensive Modelling System. From the transport sector perspective, some of the impacts are driven by the trend of electricity price estimated from the energy modelling system. Nevertheless, the major drivers to a low carbon transport sector are policies related to increased fuel efficiency of conventional drivetrain technologies, improvement of demand management (e.g. increase of public transport and car sharing services/usage) and diffusion of environmentally friendly vehicles (e.g. electric vehicles). The final modelling results of the REFLEX project will be available from October 2018. The analysis of the impacts and challenges of future scenarios is performed in terms of transport, environmental and social indicators. The diffusion of e-vehicles produces a consistent reduction of future greenhouse gas emissions, although the decarbonisation target can be achieved only with the contribution of complementary transport policies on demand management and supporting the deployment of low-emission alternative energy for non-road transport modes. The paper explores the implications through time of transport policy measures on mobility and environment, underlying to what extent they can contribute to a decarbonisation of the transport sector. Acknowledgements: The results refer to the REFLEX project which has received grants from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 691685.

Keywords: decarbonisation, greenhouse gas emissions, e-mobility, transport policies, energy

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Authors: Ifeoma Anozie, Teka Apalata, Dominic Abaver

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Introduction: Despite use of Anti-retroviral therapy to reduce the incidence of opportunistic infections among HIV/AIDS patients, rapid episodes of re-infection after deworming are still common occurrences because pharmaceutical intervention alone does not prevent reinfection. Unsafe water and inadequate personal hygiene and parasitic infections are widely expected to accelerate the progression of HIV infection. This is because the chronic immunosuppression of HIV infection encourages susceptibility to opportunistic (including parasitic) infections which is linked to CD4+ cell count of <200 cells/μl. Intestinal parasites such as G. intestinalis and Entamoeba spp are ubiquitous protozoa that remain infectious over a long time in an environment and show resistance to standard disinfection. To control re-infection, the social factors that underpin the prevention need to be controlled. This study aims at prevention of intestinal parasites in people living with HIV/AIDS by using a treatment, hygiene education and sanitation (THEdS) bundle approach. Methods: This study was conducted in four clinics (Ngangelizwe health centre, Tsolo gateway clinic, Idutywa health centre and Nqamakwe health centre) across the seven districts in Eastern cape, South Africa. The four clinics were divided in two: experimental and control, for the purpose of intervention. Data was collected from March 2019 to February 2020. Six hundred participants were screened for intestinal parasitic infections. Stool samples were collected and analysed twice: before (Pre-test infection screening) and after (Post-test re-infection) THEdS bundle intervention. The experimental clinics received full intervention package, which include therapeutic treatment, health education on personal hygiene and sanitation training, while the control clinics received only therapeutic treatment for those found with intestinal parasitic infections. Results: Baseline prevalence of Intestinal Parasites isolated shows 12 intestinal parasites with overall frequency of 65, with Ascaris lumbricoides having most frequency (44.6%). The intervention had a cure rate of 60%, with odd ratio of 1.42, which indicates that the intervention group is 1.42 times more likely of parasite clearing as compared to the control group. The relative risk ratio of 1.17 signifies that there is 1.17 times more likelihood to clear intestinal parasite if there no intervention. Discussion and conclusion: Infection with multiple parasites can cause health defects, especially among HIV/AIDS patients. Efficiency of some HIV vaccines in HIV/AIDS patients is affected because treatment of re-infection amplifies drug resistance, affects the efficacy of the front-line drugs, and still permits transmission. In South Africa, treatment of intestinal parasites is usually offered to clinic attending HIV/AIDS patients upon suspicion but not as a mandate for patients being initiated into Antiretroviral (ART) program. The effectiveness of THEdS bundle advocates for inclusiveness of mandatory screening for intestinal parasitic infections among attendees of HIV/Aids clinics on regular basis.

Keywords: cure rate, , HIV/AIDS patients, intestinal parasites, intervention studies, reinfection rate

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Authors: J. Desbrieres, M. Popa, C. Peptu, S. Bacaita

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Because of their favorable properties (non-toxicity, biodegradability, mucoadhesivity etc.), polysaccharides were studied as biomaterials and as pharmaceutical excipients in drug formulations. These formulations may be produced in a wide variety of forms including hydrogels, hydrogel based particles (or capsules), films etc. In these formulations, the polysaccharide based materials are able to provide local delivery of loaded therapeutic agents but their delivery can be rapid and not easily time-controllable due to, particularly, the burst effect. This leads to a loss in drug efficiency and lifetime. To overcome the consequences of burst effect, systems involving liposomes incorporated into polysaccharide hydrogels may appear as a promising material in tissue engineering, regenerative medicine and drug loading systems. Liposomes are spherical self-closed structures, composed of curved lipid bilayers, which enclose part of the surrounding solvent into their structure. The simplicity of production, their biocompatibility, the size and similar composition of cells, the possibility of size adjustment for specific applications, the ability of hydrophilic or/and hydrophobic drug loading make them a revolutionary tool in nanomedicine and biomedical domain. Drug delivery systems were developed as hydrogels containing chitosan or carboxymethylcellulose (CMC) as polysaccharides and gelatin (GEL) as polypeptide, and phosphatidylcholine or phosphatidylcholine/cholesterol liposomes able to accurately control this delivery, without any burst effect. Hydrogels based on CMC were covalently crosslinked using glutaraldehyde, whereas chitosan based hydrogels were double crosslinked (ionically using sodium tripolyphosphate or sodium sulphate and covalently using glutaraldehyde). It has been proven that the liposome integrity is highly protected during the crosslinking procedure for the formation of the film network. Calcein was used as model active matter for delivery experiments. Multi-Lamellar vesicles (MLV) and Small Uni-Lamellar Vesicles (SUV) were prepared and compared. The liposomes are well distributed throughout the whole area of the film, and the vesicle distribution is equivalent (for both types of liposomes evaluated) on the film surface as well as deeper (100 microns) in the film matrix. An obvious decrease of the burst effect was observed in presence of liposomes as well as a uniform increase of calcein release that continues even at large time scales. Liposomes act as an extra barrier for calcein release. Systems containing MLVs release higher amounts of calcein compared to systems containing SUVs, although these liposomes are more stable in the matrix and diffuse with difficulty. This difference comes from the higher quantity of calcein present within the MLV in relation with their size. Modeling of release kinetics curves was performed and the release of hydrophilic drugs may be described by a multi-scale mechanism characterized by four distinct phases, each of them being characterized by a different kinetics model (Higuchi equation, Korsmeyer-Peppas model etc.). Knowledge of such models will be a very interesting tool for designing new formulations for tissue engineering, regenerative medicine and drug delivery systems.

Keywords: controlled and delayed release, hydrogels, liposomes, polysaccharides

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Authors: Giulia Fredi, Andrea Dorigato, Luca Fambri, Alessandro Pegoretti

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Thermal energy storage (TES) is the storage of heat for later use, thus filling the gap between energy request and supply. The most widely used materials for TES are the organic solid-liquid phase change materials (PCMs), such as paraffin. These materials store/release a high amount of latent heat thanks to their high specific melting enthalpy, operate in a narrow temperature range and have a tunable working temperature. However, they suffer from a low thermal conductivity and need to be confined to prevent leakage. These two issues can be tackled by confining PCMs with carbon nanotubes (CNTs). TES applications include the buildings industry, solar thermal energy collection and thermal management of electronics. In most cases, TES systems are an additional component to be added to the main structure, but if weight and volume savings are key issues, it would be advantageous to embed the TES functionality directly in the structure. Such multifunctional materials could be employed in the automotive industry, where the diffusion of lightweight structures could complicate the thermal management of the cockpit environment or of other temperature sensitive components. This work aims to produce epoxy/carbon structural laminates containing CNT-stabilized paraffin. CNTs were added to molten paraffin in a fraction of 10 wt%, as this was the minimum amount at which no leakage was detected above the melting temperature (45°C). The paraffin/CNT blend was cryogenically milled to obtain particles with an average size of 50 µm. They were added in various percentages (20, 30 and 40 wt%) to an epoxy/hardener formulation, which was used as a matrix to produce laminates through a wet layup technique, by stacking five plies of a plain carbon fiber fabric. The samples were characterized microstructurally, thermally and mechanically. Differential scanning calorimetry (DSC) tests showed that the paraffin kept its ability to melt and crystallize also in the laminates, and the melting enthalpy was almost proportional to the paraffin weight fraction. These thermal properties were retained after fifty heating/cooling cycles. Laser flash analysis showed that the thermal conductivity through the thickness increased with an increase of the PCM, due to the presence of CNTs. The ability of the developed laminates to contribute to the thermal management was also assessed by monitoring their cooling rates through a thermal camera. Three-point bending tests showed that the flexural modulus was only slightly impaired by the presence of the paraffin/CNT particles, while a more sensible decrease of the stress and strain at break and the interlaminar shear strength was detected. Optical and scanning electron microscope images revealed that these could be attributed to the preferential location of the PCM in the interlaminar region. These results demonstrated the feasibility of multifunctional structural TES composites and highlighted that the PCM size and distribution affect the mechanical properties. In this perspective, this group is working on the encapsulation of paraffin in a sol-gel derived organosilica shell. Submicron spheres have been produced, and the current activity focuses on the optimization of the synthesis parameters to increase the emulsion efficiency.

Keywords: carbon fibers, carbon nanotubes, lightweight materials, multifunctional composites, thermal energy storage

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Authors: Marcin Dębowski, Marcin Zieliński, Mirosław Krzemieniewski

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As methane fermentation is a complex series of successive biochemical transformations, its subsequent stages are determined, to a various extent, by physical and chemical factors. A specific state of equilibrium is being settled in the functioning fermentation system between environmental conditions and the rate of biochemical reactions and products of successive transformations. In the case of physical factors that influence the effectiveness of methane fermentation transformations, the key significance is ascribed to temperature and intensity of biomass agitation. Among the chemical factors, significant are pH value, type, and availability of the culture medium (to put it simply: the C/N ratio) as well as the presence of toxic substances. One of the important elements which influence the effectiveness of methane fermentation is the pre-treatment of organic substrates and the mode in which the organic matter is made available to anaerobes. Out of all known and described methods for organic substrate pre-treatment before methane fermentation process, the ultrasound disintegration is one of the most interesting technologies. Investigations undertaken on the ultrasound field and the use of installations operating on the existing systems result principally from very wide and universal technological possibilities offered by the sonication process. This physical factor may induce deep physicochemical changes in ultrasonicated substrates that are highly beneficial from the viewpoint of methane fermentation processes. In this case, special role is ascribed to disintegration of biomass that is further subjected to methane fermentation. Once cell walls are damaged, cytoplasm and cellular enzymes are released. The released substances – either in dissolved or colloidal form – are immediately available to anaerobic bacteria for biodegradation. To ensure the maximal release of organic matter from dead biomass cells, disintegration processes are aimed to achieve particle size below 50 μm. It has been demonstrated in many research works and in systems operating in the technical scale that immediately after substrate supersonication the content of organic matter (characterized by COD, BOD5 and TOC indices) was increasing in the dissolved phase of sedimentation water. This phenomenon points to the immediate sonolysis of solid substances contained in the biomass and to the release of cell material, and consequently to the intensification of the hydrolytic phase of fermentation. It results in a significant reduction of fermentation time and increased effectiveness of production of gaseous metabolites of anaerobic bacteria. Because disintegration of Virginia fanpetals biomass via ultrasounds applied in order to intensify its conversion is a novel technique, it is often underestimated by exploiters of agri-biogas works. It has, however, many advantages that have a direct impact on its technological and economical superiority over thus far applied methods of biomass conversion. As for now, ultrasound disintegrators for biomass conversion are not produced on the mass-scale, but by specialized groups in scientific or R&D centers. Therefore, their quality and effectiveness are to a large extent determined by their manufacturers’ knowledge and skills in the fields of acoustics and electronic engineering.

Keywords: ultrasound disintegration, biomass, methane fermentation, biogas, Virginia fanpetals

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Authors: Golson Mohamed, Yasmine Gamasy, Khaled EL-Khatib, Anas Al-Natour, Shady Fadel, Haytham Rashwan, Haytham Badawy, Nadia Farghaly

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Introduction: Wilm's tumor is the most common malignant renal tumor in children. Much progress has been made in the management of patients with this malignancy over the last 3 decades. Today treatments are based on several trials and studies conducted by the International Society of Pediatric Oncology (SIOP) in Europe and National Wilm's Tumor Study Group (NWTS) in the USA. It is necessary for us to understand why do we follow either of the protocols, NWTS which follows the upfront surgery principle or the SIOP which follows the upfront chemotherapy principle in all stages of the disease. Objective: The aim of is to assess outcome in patients treated with preoperative chemotherapy and patients treated with upfront surgery to compare their effect on overall survival. Study design: to decide which protocol to follow, study was carried out on records for patients aged 1 day to 18 years old suffering from Wilm's tumor who were admitted to Alexandria University Hospital, pediatric oncology, pediatric urology and pediatric surgery departments, with a retrospective survey records from 2010 to 2015, Design and editing of the transfer sheet with a (PRISMA flow study) Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Data were fed to the computer and analyzed using IBM SPSS software package version 20.0. (11) Qualitative data were described using number and percent. Quantitative data were described using Range (minimum and maximum), mean, standard deviation and median. Comparison between different groups regarding categorical variables was tested using Chi-square test. When more than 20% of the cells have expected count less than 5, correction for chi-square was conducted using Fisher’s Exact test or Monte Carlo correction. The distributions of quantitative variables were tested for normality using Kolmogorov-Smirnov test, Shapiro-Wilk test, and D'Agstino test, if it reveals normal data distribution, parametric tests were applied. If the data were abnormally distributed, non-parametric tests were used. For normally distributed data, a comparison between two independent populations was done using independent t-test. For abnormally distributed data, comparison between two independent populations was done using Mann-Whitney test. Significance of the obtained results was judged at the 5% level. Results: A significantly statistical difference was observed for survival between the two studied groups favoring the upfront chemotherapy(86.4%)as compared to the upfront surgery group (59.3%) where P=0.009. As regard complication, 20 cases (74.1%) out of 27 were complicated in the group of patients treated with upfront surgery. Meanwhile, 30 cases (68.2%) out of 44 had complications in patients treated with upfront chemotherapy. Also, the incidence of intraoperative complication (rupture) was less in upfront chemotherapy group as compared to upfront surgery group. Conclusion: Upfront chemotherapy has superiority over upfront surgery.As the patient who started with upfront chemotherapy shown, higher survival rate, less percent in complication, less percent needed for radiotherapy, and less rate in recurrence.

Keywords: Wilm's tumor, renal tumor, chemotherapy, surgery

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Authors: Juliane Toce, Steven Holochwost

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A substantial and growing literature has demonstrated that arts education benefits young children’s socioemotional and cognitive development. Less is known about the capacity of arts-integrated instruction to yield benefits to similar domains, particularly among demographically and socioeconomically diverse groups of young children. However, the small literature on this topic suggests that arts-integrated instruction may foster young children’s socioemotional and cognitive development by presenting opportunities to 1) engage in instructional content in diverse ways, 2) experience and regulate strong emotions, 3) experience growth-oriented feedback, and 4) engage in collaborative work with peers. Start with the Art is a new program of arts-integrated instruction currently being implemented in four schools in a school district that serves students from a diverse range of backgrounds. The program employs a co-teaching model in which teaching artists and classroom teachers engage in collaborative lesson planning and instruction over the course of the academic year and is currently the focus of an impact study featuring a randomized-control design, as well as an implementation study, both of which are funded through an Educational Innovation and Research grant from the United States Department of Education. The paper will present the early results from the Start with the Art implementation study. These results will provide an overview of the extent to which the program was implemented in accordance with design, with a particular emphasis on the degree to which the four opportunities enumerated above (e.g., opportunities to engage in instructional content in diverse ways) were presented to students. There will be a review key factors that may influence the fidelity of implementation, including classroom teachers’ reception of the program and the extent to which extant conditions in the classroom (e.g., the overall level of classroom organization) may have impacted implementation fidelity. With the explicit purpose of creating a program that values and meets the needs of the teachers and students, Start with the Art incorporates the feedback from individuals participating in the intervention. Tracing its trajectory from inception to ongoing development and examining the adaptive changes made in response to teachers' transformative experiences in the post-pandemic classroom, Start with the Art continues to solicit input from experts in integrating artistic content into core curricula within educational settings catering to students from under-represented backgrounds in the arts. Leveraging the input from this rich consortium of experts has allowed for a comprehensive evaluation of the program’s implementation. The early findings derived from the implementation study emphasize the potential of arts-integrated instruction to incorporate restorative practices. Such practices serve as a crucial support system for both students and educators, providing avenues for children to express themselves, heal emotionally, and foster social development, while empowering teachers to create more empathetic, inclusive, and supportive learning environments. This all-encompassing analysis spotlights Start with the Art’s adaptability to any learning environment through the program’s effectiveness, resilience, and its capacity to transform - through art - the classroom experience within the ever-evolving landscape of education.

Keywords: arts-integration, social emotional learning, diverse learners, co-teaching, teaching artists, post-pandemic teaching

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Authors: Mihaela Beregoi, Horia Iovu, Cristina Busuioc, Alexandru Evanghelidis, Elena Matei, Monica Enculescu, Ionut Enculescu

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Nanomaterials field is very attractive for all researchers who are attempting to develop new devices with the same or improved properties than the micro-sized ones, while reducing the reagents and power consumptions. In this way, a wide range of nanomaterials were fabricated and integrated in applications for electronics, optoelectronics, solar cells, tissue reconstruction and drug delivery. Obviously, the most appealing ones are those dedicated to the medical domain. Different types of nano-sized materials, such as particles, fibers, films etc., can be synthesized by using physical, chemical or electrochemical methods. One of these techniques is electrospinning, which enable the production of fibers with nanometric dimensions by pumping a polymeric solution in a high electric field; due to the electrostatic charging and solvent evaporation, the precursor mixture is converted into nonwoven meshes with different fiber densities and mechanical properties. Moreover, polyaniline is a conducting polymer with interesting optical properties, suitable for displays and electrochromic windows. Otherwise, polyaniline is an electroactive polymer that can contract/expand by applying electric stimuli, due to the oxidation/reduction reactions which take place in the polymer chains. These two main properties can be exploited in order to synthesize smart materials that change their dimensions, exhibiting in the same time good electrochromic properties. In the context aforesaid, a poly(methyl metacrylate) solution was spun to get webs composed of fibers with diameter values between 500 nm and 1 µm. Further, the polymer meshes were covered with a gold layer in order to make them conductive and also appropriate as working electrode in an electrochemical cell. The gold shell was deposited by DC sputtering. Such metalized fibers can be transformed into smart materials by covering them with a thin layer of conductive polymer. Thus, the webs were coated with a polyaniline film by the electrochemical route, starting from and aqueous solution of aniline and sulfuric acid, where sulfuric acid acts as oxidant agent. For the polymerization of aniline, a saturated calomel electrode was employed as reference, a platinum plate as counter electrode and the gold covered webs as working electrode. Chronoamperometry was selected as deposition method for polyaniline, by modifying the deposition time. Metalized meshes with different fiber densities were used, the transmission ranging between 70 and 80 %. The morphological investigation showed that polyaniline layer has a granular structure for all deposition experiments. As well, some preliminary optical tests were done by using sulfuric acid as electrolyte, which revealed the modification of polyaniline colour from green to dark blue when applying a voltage. In conclusion, new multilayered materials were obtained by a simple approach: the merge of the electrospinning method benefits with polyaniline chemistry. This synthesis method allows the fabrication of structures with reproducible characteristics, suitable for display or tissue substituents.

Keywords: electrospinning, fibers, smart materials, polyaniline

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Authors: Lola T. Alimkhodjaeva, Lola T. Zakirova, Soniya S. Ziyavidenova

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Background: Breast cancer (BC) is still one of the urgent oncology problems. The essential obstacle to the full anti-tumor therapy implementation is drug resistance development. Taking into account the fact that chemotherapy is main antitumor treatment in BC patients, the important task is to improve treatment results. Certain success in overcoming this situation has been associated with the use of methods of extracorporeal blood treatment (ECBT), plasmapheresis. Materials and Methods: We examined 129 women with resistant BC stages 3-4, aged between 56 to 62 years who had previously received 2 courses of CAF chemotherapy. All patients additionally underwent 2 courses of CAF chemotherapy but against the background ECBT with ultrasonic exposure. We studied the following parameters: 1. The highlights of peripheral blood before and after therapy. 2. The state of cellular immunity and identification of activation markers CD23 +, CD25 +, CD38 +, CD95 + on lymphocytes was performed using monoclonal antibodies. Evaluation of humoral immunity was determined by the level of main classes of immunoglobulins IgG, IgA, IgM in serum. 3. The degree of tumor regression was assessed by WHO recommended 4 gradations. (complete - 100%, partial - more than 50% of initial size, process stabilization–regression is less than 50% of initial size and tumor advance progressing). 4. Medical pathomorphism in the tumor was determined by Lavnikova. 5. The study of immediate and remote results, up to 3 years and more. Results and Discussion: After performing extracorporeal blood treatment anemia occurred in 38.9%, leukopenia in 36.8%, thrombocytopenia in 34.6%, hypolymphemia in 26.8%. Studies of immunoglobulin fractions in blood serum were able to establish a certain relationship between the classes of immunoglobulin A, G, M and their functions. The results showed that after treatment the values of main immunoglobulins in patients’ serum approximated to normal. Analysis of expression of activation markers CD25 + cells bearing receptors for IL-2 (IL-2Rα chain) and CD95 + lymphocytes that were mediated physiological apoptosis showed the tendency to increase, which apparently was due to activation of cellular immunity cytokines allocated by ultrasonic treatment. To carry out ECBT on the background of ultrasonic treatment improved the parameters of the immune system, which were expressed in stimulation of cellular immunity and correcting imbalances in humoral immunity. The key indicator of conducted treatment efficiency is the immediate result measured by the degree of tumor regression. After ECBT performance the complete regression was 10.3%, partial response - 55.5%, process stabilization - 34.5%, tumor advance progressing no observed. Morphological investigations of tumor determined therapeutic pathomorphism grade 2 in 15%, in 25% - grade 3 and therapeutic pathomorphism grade 4 in 60% of patients. One of the main criteria for the effect of conducted treatment is to study the remission terms in the postoperative period (up to 3 years or more). The remission terms up to 3 years with ECBT was 34.5%, 5-year survival was 54%. Carried out research suggests that a comprehensive study of immunological and clinical course of breast cancer allows the differentiated approach to the choice of methods for effective treatment.

Keywords: breast cancer, immunoglobulins, extracorporeal blood treatment, chemotherapy

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Authors: Olugbenga S. Alebiosu, Olusola H. Adekanmbi, Oluwatoyin T. Ogundipe

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Pollen and spores have been identified as major airborne bio-particles inducing respiratory disorders such as asthma, allergic rhinitis and atopic dermatitis among hypersensitive individuals. An aeropalynological study was conducted within a one year sampling period with a view to investigating the monthly depositional rate of atmospheric pollen and spores; influence of the immediate vegetation on airborne pollen distribution; allergenic potentials of dominant atmospheric pollen types at selected study locations in Bauchi and Taraba states, Northwestern Nigeria. A tauber-like pollen trap was employed in aerosampling with the sampler positioned at a height of 5 feet above the ground, followed by a monthly collection of the recipient solution for the sampling period. The collected samples were subjected to acetolysis treatment, examined microscopically with the identification of pollen grains and spores using reference materials and published photomicrographs. Plants within the surrounding vegetation were enumerated. Crude protein contents extracted from pollen types found to be commonly dominant at both study locations; Senna siamea, Terminalia cattapa, Panicum maximum and Zea mays were used to sensitize Musmusculus. Histopathological studies of bronchi and lung sections from certain dead M.musculus in the test groups was conducted. Blood samples were collected from the pre-orbital vein of M.musculus and processed for serological and haematological (differential and total white blood cell counts) studies. ELISA was used in determining the levels of serological parameters: IgE and cytokines (TNF-, IL-5, and IL-13). Statistical significance was observed in the correlation between the levels of serological and haematological parameters elicited by each test group, differences between the levels of serological and haematological parameters elicited by each test group and those of the control, as well as at varying sensitization periods. The results from this study revealed dominant airborne pollen types across the study locations; Syzygiumguineense, Tridaxprocumbens, Elaeisguineensis, Mimosa sp., Borreria sp., Terminalia sp., Senna sp. and Poaceae. Nephrolepis sp., Pteris sp. and a trilete fern also produced spores. This study also revealed that some of the airborne pollen types were produced by local plants at the study locations. Bronchi sections of M.musculus after first and second sensitizations, as well as lung section after first sensitization with Senna siamea, showed areas of necrosis. Statistical significance was recorded in the correlation between the levels of some serological and haematological parameters produced by each test group and those of the control, as well as at certain sensitization periods. The study revealed some candidate pollen allergens at the study locations allergy sufferers and also established a complexity of interaction between immune cells, IgE and cytokines at varied periods of mice sensitization and forming a paradigm of human immune response to different pollen allergens. However, it is expedient that further studies should be conducted on these candidate pollen allergens for their allergenicity potential in humans within their immediate environment.

Keywords: airborne, hypersensitive, mus musculus, pollen allergens, respiratory, tauber-like

Procedia PDF Downloads 115

Authors: Banafsheh Nikmehr, Mohsen Bahrami, Yueqiang Song, Anuradha Koduru, Ayse K. Vuruskan, Hongkun Lu, Mallory Pitts, Tolga B. Mesen, Tamer M. Yalcinkaya

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The number of people who receive in vitro fertilization (IVF) treatment has increased on a startling trajectory over the past two decades. Despite advances in this field, particularly the introduction of intracytoplasmic sperm injection (ICSI) and the preimplantation genetic screening (PGS), the IVF success remains low. A major factor contributing to IVF failure is embryonic aneuploidy (abnormal chromosome content), which often results in miscarriage and birth defects. Although PGS is often used as the standard diagnostic tool to identify aneuploid embryos, it is an invasive approach that could affect the embryo development, and yet inaccessible to many patients due its high costs. As such, there is a clear need for a non-invasive cost-effective approach to identify euploid embryos for single embryo transfer (SET). The reported differences between morphokinetic behaviors of aneuploid and euploid embryos has shown promise to address this need. However, current literature is inconclusive and further research is urgently needed to translate current findings into clinical diagnostics. In this ongoing study, we found significant differences between morphokinetic behaviors of euploid and aneuploid embryos that provides important insights and reaffirms the promise of such behaviors for developing non-invasive methodologies. Methodology—A total of 242 embryos (euploid: 149, aneuploid: 93) from 74 patients who underwent IVF treatment in Carolinas Fertility Clinics in Winston-Salem, NC, were analyzed. All embryos were incubated in an EmbryoScope incubator. The patients were randomly selected from January 2019 to June 2021 with most patients having both euploid and aneuploid embryos. All embryos reached the blastocyst stage and had known PGS outcomes. The ploidy assessment was done by a third-party testing laboratory on day 5-7 embryo biopsies. The morphokinetic variables of each embryo were measured by the EmbryoViewer software (Uniesense FertiliTech) on time-lapse images using 7 focal depths. We compared the time to: pronuclei fading (tPNf), division to 2,3,…,9 cells (t2, t3,…,t9), start of embryo compaction (tSC), Morula formation (tM), start of blastocyst formation (tSC), blastocyst formation (tB), and blastocyst expansion (tEB), as well as intervals between them (e.g., c23 = t3 – t2). We used a mixed regression method for our statistical analyses to account for the correlation between multiple embryos per patient. Major Findings— The average age of the patients was 35.04 yrs. The average patient age associated with euploid and aneuploid embryos was not different (P = 0.6454). We found a significant difference in c45 = t5-t4 (P = 0.0298). Our results indicated this interval on average lasts significantly longer for aneuploid embryos - c45(aneuploid) = 11.93hr vs c45(euploid) = 7.97hr. In a separate analysis limited to embryos from the same patients (patients = 47, total embryos=200, euploid=112, aneuploid=88), we obtained the same results (P = 0.0316). The statistical power for this analysis exceeded 87%. No other variable was different between the two groups. Conclusion— Our results demonstrate the importance of morphokinetic variables as potential biomarkers that could aid in non-invasively characterizing euploid and aneuploid embryos. We seek to study a larger population of embryos and incorporate the embryo quality in future studies.

Keywords: IVF, embryo, euploidy, aneuploidy, morphokinteic

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Authors: Allison Herlene Du Plessis, Dalena (R.M.) Van Rooyen, Wilma Ten Ham-Baloyi, Sihaam Jardien-Baboo

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Introduction: Women die in pregnancy and childbirth for five main reasons—severe bleeding, infections, unsafe abortions, hypertensive disorders (pre-eclampsia and eclampsia), and medical complications including cardiac disease, diabetes, or HIV/AIDS complicated by pregnancy. In 2015, WHO classified sepsis as the third highest cause for maternal mortalities in the world. Chorioamnionitis is a clinical syndrome of intrauterine infection during any stage of the pregnancy and it refers to ascending bacteria from the vaginal canal up into the uterus, causing infection. While the incidence rates for chorioamnionitis are not well documented, complications related to chorioamnionitis are well documented and midwives still struggle to identify this condition in time due to its complex nature. Few diagnostic methods are available in public health services, due to escalated laboratory costs. Often the affordable biomarkers, such as C-reactive protein CRP, full blood count (FBC) and WBC, have low significance in diagnosing chorioamnionitis. A lack of screening impacts on effective and timeous management of chorioamnionitis, and early identification and management of risks could help to prevent neonatal complications and reduce the subsequent series of morbidities and healthcare costs of infants who are health foci of perinatal infections. Objective: This integrative literature review provides an overview of current best research evidence on the screening of women at risk for chorioamnionitis. Design: An integrative literature review was conducted using a systematic electronic literature search through EBSCOhost, Cochrane Online, Wiley Online, PubMed, Scopus and Google. Guidelines, research studies, and reports in English related to chorioamnionitis from 2008 up until 2020 were included in the study. Findings: After critical appraisal, 31 articles were included. More than one third (67%) of the literature included ranked on the three highest levels of evidence (Level I, II and III). Data extracted regarding screening for chorioamnionitis was synthesized into four themes, namely: screening by clinical signs and symptoms, screening by causative factors of chorioamnionitis, screening of obstetric history, and essential biomarkers to diagnose chorioamnionitis. Key conclusions: There are factors that can be used by midwives to identify women at risk for chorioamnionitis. However, there are a paucity of established sociological, epidemiological and behavioral factors to screen this population. Several biomarkers are available to diagnose chorioamnionitis. Increased Interleukin-6 in amniotic fluid is the better indicator and strongest predictor of histological chorioamnionitis, whereas the available rapid matrix-metalloproteinase-8 test requires further testing. Maternal white blood cells count (WBC) has shown poor selectivity and sensitivity, and C-reactive protein (CRP) thresholds varied among studies and are not ideal for conclusive diagnosis of subclinical chorioamnionitis. Implications for practice: Screening of women at risk for chorioamnionitis by health care providers providing care for pregnant women, including midwives, is important for diagnosis and management before complications arise, particularly in resource-constraint settings.

Keywords: chorioamnionitis, guidelines, best evidence, screening, diagnosis, pregnant women

Procedia PDF Downloads 101

Authors: Marcin Zieliński, Marcin Dębowski, Mirosław Krzemieniewski

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The anaerobic degradation of substrates is limited especially by the rate and effectiveness of the first (hydrolytic) stage of fermentation. This stage may be intensified through pre-treatment of substrate aimed at disintegration of the solid phase and destruction of substrate tissues and cells. The most frequently applied criterion of disintegration outcomes evaluation is the increase in biogas recovery owing to the possibility of its use for energetic purposes and, simultaneously, recovery of input energy consumed for the pre-treatment of substrate before fermentation. Hydrodynamic cavitation is one of the methods for organic substrate disintegration that has a high implementation potential. Cavitation is explained as the phenomenon of the formation of discontinuity cavities filled with vapor or gas in a liquid induced by pressure drop to the critical value. It is induced by a varying field of pressures. A void needs to occur in the flow in which the pressure first drops to the value close to the pressure of saturated vapor and then increases. The process of cavitation conducted under controlled conditions was found to significantly improve the effectiveness of anaerobic conversion of organic substrates having various characteristics. This phenomenon allows effective damage and disintegration of cellular and tissue structures. Disintegration of structures and release of organic compounds to the dissolved phase has a direct effect on the intensification of biogas production in the process of anaerobic fermentation, on reduced dry matter content in the post-fermentation sludge as well as a high degree of its hygienization and its increased susceptibility to dehydration. A device the efficiency of which was confirmed both in laboratory conditions and in systems operating in the technical scale is a hydrodynamic generator of cavitation. Cavitators, agitators and emulsifiers constructed and tested worldwide so far have been characterized by low efficiency and high energy demand. Many of them proved effective under laboratory conditions but failed under industrial ones. The only task successfully realized by these appliances and utilized on a wider scale is the heating of liquids. For this reason, their usability was limited to the function of heating installations. Design of the presented cavitation generator allows achieving satisfactory energy efficiency and enables its use under industrial conditions in depolymerization processes of biomass with various characteristics. Investigations conducted on the laboratory and industrial scale confirmed the effectiveness of applying cavitation in the process of biomass destruction. The use of the cavitation generator in laboratory studies for disintegration of sewage sludge allowed increasing biogas production by ca. 30% and shortening the treatment process by ca. 20 - 25%. The shortening of the technological process and increase of wastewater treatment plant effectiveness may delay investments aimed at increasing system output. The use of a mechanical cavitator and application of repeated cavitation process (4-6 times) enables significant acceleration of the biogassing process. In addition, mechanical cavitation accelerates increases in COD and VFA levels.

Keywords: hydrodynamic cavitation, pretreatment, biomass, methane fermentation, Virginia fanpetals

Procedia PDF Downloads 415

Authors: Fei Jia, Xingjian Bai, Xiaowei Zhang, Wenjie Yan, Ruitong Dai, Xingmin Li, Jozef Kokini

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Pseudomonas aeruginosa is a Gram-negative, aerobic, opportunistic human pathogen that is present in the soil, water, and food. This microbe has been recognized as a representative food-borne spoilage bacterium that can lead to many types of infections. Considering the casualties and property loss caused by P. aeruginosa, the development of a rapid and reliable technique for the detection of P. aeruginosa is crucial. The whole-cell aptasensor, an emerging biosensor using aptamer as a capture probe to bind to the whole cell, for food-borne pathogens detection has attracted much attention due to its convenience and high sensitivity. Here, a low-field magnetic resonance imaging (LF-MRI) aptasensor for the rapid detection of P. aeruginosa was developed. The basic detection principle of the magnetic relaxation switch (MRSw) nanosensor lies on the ‘T₂-shortening’ effect of magnetic nanoparticles in NMR measurements. Briefly speaking, the transverse relaxation time (T₂) of neighboring water protons get shortened when magnetic nanoparticles are clustered due to the cross-linking upon the recognition and binding of biological targets, or simply when the concentration of the magnetic nanoparticles increased. Such shortening is related to both the state change (aggregation or dissociation) and the concentration change of magnetic nanoparticles and can be detected using NMR relaxometry or MRI scanners. In this work, two different sizes of magnetic nanoparticles, which are 10 nm (MN₁₀) and 400 nm (MN₄₀₀) in diameter, were first immobilized with anti- P. aeruginosa aptamer through 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) chemistry separately, to capture and enrich the P. aeruginosa cells. When incubating with the target, a ‘sandwich’ (MN₁₀-bacteria-MN₄₀₀) complex are formed driven by the bonding of MN400 with P. aeruginosa through aptamer recognition, as well as the conjugate aggregation of MN₁₀ on the surface of P. aeruginosa. Due to the different magnetic performance of the MN₁₀ and MN₄₀₀ in the magnetic field caused by their different saturation magnetization, the MN₁₀-bacteria-MN₄₀₀ complex, as well as the unreacted MN₄₀₀ in the solution, can be quickly removed by magnetic separation, and as a result, only unreacted MN₁₀ remain in the solution. The remaining MN₁₀, which are superparamagnetic and stable in low field magnetic field, work as a signal readout for T₂ measurement. Under the optimum condition, the LF-MRI platform provides both image analysis and quantitative detection of P. aeruginosa, with the detection limit as low as 100 cfu/mL. The feasibility and specificity of the aptasensor are demonstrated in detecting real food samples and validated by using plate counting methods. Only two steps and less than 2 hours needed for the detection procedure, this robust aptasensor can detect P. aeruginosa with a wide linear range from 3.1 ×10² cfu/mL to 3.1 ×10⁷ cfu/mL, which is superior to conventional plate counting method and other molecular biology testing assay. Moreover, the aptasensor has a potential to detect other bacteria or toxins by changing suitable aptamers. Considering the excellent accuracy, feasibility, and practicality, the whole-cell aptasensor provides a promising platform for a quick, direct and accurate determination of food-borne pathogens at cell-level.

Keywords: magnetic resonance imaging, meat spoilage, P. aeruginosa, transverse relaxation time

Procedia PDF Downloads 130

Authors: Philipp Wenger, Michael Beltle, Stefan Tenbohlen, Uwe Riechert

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The integration of renewable energy introduces new challenges to the transmission grid, as the power generation is located far from load centers. The associated necessary long-range power transmission increases the demand for high voltage direct current (HVDC) transmission lines and DC distribution grids. HVDC gas-insulated switchgears (GIS) are considered being a key technology, due to the combination of the DC technology and the long operation experiences of AC-GIS. To ensure long-term reliability of such systems, insulation defects must be detected in an early stage. Operational experience with AC systems has proven evidence, that most failures, which can be attributed to breakdowns of the insulation system, can be detected and identified via partial discharge (PD) measurements beforehand. In AC systems the identification of defects relies on the phase resolved partial discharge pattern (PRPD). Since there is no phase information within DC systems this method cannot be transferred to DC PD diagnostic. Furthermore, the behaviour of e.g. free-moving particles differs significantly at DC: Under the influence of a constant direct electric field, charge carriers can accumulate on particles’ surfaces. As a result, a particle can lift-off, oscillate between the inner conductor and the enclosure or rapidly bounces at just one electrode, which is known as firefly motion. Depending on the motion and the relative position of the particle to the electrodes, broadband electromagnetic PD pulses are emitted, which can be recorded by ultra-high frequency (UHF) measuring methods. PDs are often accompanied by light emissions at the particle’s tip which enables optical detection. This contribution investigates PD characteristics of free moving metallic particles in a commercially available 300 kV SF6-insulated HVDC-GIS. The influences of various defect parameters on the particle motion and the PD characteristic are evaluated experimentally. Several particle geometries, such as cylinder, lamella, spiral and sphere with different length, diameter and weight are determined. The applied DC voltage is increased stepwise from inception voltage up to UDC = ± 400 kV. Different physical detection methods are used simultaneously in a time-synchronized setup. Firstly, the electromagnetic waves emitted by the particle are recorded by an UHF measuring system. Secondly, a photomultiplier tube (PMT) detects light emission with a wavelength in the range of λ = 185…870 nm. Thirdly, a high-speed camera (HSC) tracks the particle’s motion trajectory with high accuracy. Furthermore, an electrically insulated electrode is attached to the grounded enclosure and connected to a current shunt in order to detect low frequency ion currents: The shunt measuring system’s sensitivity is in the range of 10 nA at a measuring bandwidth of bw = DC…1 MHz. Currents of charge carriers, which are generated at the particle’s tip migrate through the gas gap to the electrode and can be recorded by the current shunt. All recorded PD signals are analyzed in order to identify characteristic properties of different particles. This includes e.g. repetition rates and amplitudes of successive pulses, characteristic frequency ranges and detected signal energy of single PD pulses. Concluding, an advanced understanding of underlying physical phenomena particle motion in direct electric field can be derived.

Keywords: current shunt, free moving particles, high-speed imaging, HVDC-GIS, UHF

Procedia PDF Downloads 137