Search results for: Andrew F. Gardner

Authors: Raina J. Olsen, Andrew K. Gillespie, John W. Taylor, Cristian I. Contescu, Peter Pfeifer, James R. Morris

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While adsorbent surfaces such as graphite are known to increase the melting temperature of solid H2, this effect is normally rather small, increasing to 20 Kelvin (K) relative to 14 K in the bulk. An as-yet unidentified phase transition has been observed in a system of H2 adsorbed in a porous, locally graphitic, Saran carbon with sub-nanometer sized pores at temperatures (74-101 K) and pressures ( > 76 bar) well above the critical point of bulk H2 using hydrogen adsorption and neutron scattering experiments. Adsorption data shows a discontinuous pressure jump in the kinetics at 76 bar after nearly an hour of equilibration time, which is identified as an exothermic phase transition. This discontinuity is observed in the 87 K isotherm, but not the 77 K isotherm. At higher pressures, the measured isotherms show greater excess adsorption at 87 K than 77 K. Inelastic neutron scattering measurements also show a striking phase transition, with the amount of high angle scattering (corresponding to large momentum transfer/ large effective mass) increasing by up to a factor of 5 in the novel phase. During the course of the neutron scattering experiment, three of these reversible spectral phase transitions were observed to occur in response to only changes in sample temperature. The novel phase was observed by neutron scattering only at high H2 pressure (123 bar and 187 bar) and temperatures between 74-101 K in the sample of interest, but not at low pressure (30 bar), or in a control activated carbon at 186 bar of H2 pressure. Based on several of the more unusual observations, such as the slow equilibration and the presence of both an upper and lower temperature bound, a reasonable hypothesis is that this phase forms only in the presence of a high concentration of ortho-H2 (nuclear spin S=1). The increase in adsorption with temperature, temperatures which cross the lower temperature bound observed by neutron scattering, indicates that this novel phase is denser. Structural characterization data on the adsorbent shows that it may support a commensurate solid phase denser than those known to exist on graphite at much lower temperatures. Whatever this phase is eventually proven to be, these results show that surfaces can have a more striking effect on hydrogen phases than previously thought.

Keywords: adsorbed phases, hydrogen, neutron scattering, nuclear spin

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Authors: Khaled Al-Badani, Andrew Norbury, Essam Elmshawet, Glynn Rotwell, Ian Jenkinson , James Ren

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Micro welding procedures are widely used for joining materials, developing duplex components or functional surfaces, through various methods such as Micro Discharge Welding or Spot Welding process, which can be found in the engineering, aerospace, automotive, biochemical, biomedical and numerous other industries. The relationship between the material properties, structure and processing is very important to improve the structural integrity and the final performance of the welded joints. This includes controlling the shape and the size of the welding nugget, state of the heat affected zone, residual stress, etc. Nowadays, modern high volume productions require the welding of much versatile shapes/sizes and material systems that are suitable for various applications. Hence, an improved understanding of the micro welding process and the digital tools, which are based on computational numerical modelling linking key welding parameters, dimensional attributes and functional performance of the weldment, would directly benefit the industry in developing products that meet current and future market demands. This paper will introduce recent work on developing an integrated experimental and numerical modelling code for micro welding techniques. This includes similar and dissimilar materials for both ferrous and non-ferrous metals, at different scales. The paper will also produce a comparative study, concerning the differences between the micro discharge welding process and the spot welding technique, in regards to the size effect of the welding zone and the changes in the material structure. Numerical modelling method for the micro welding processes and its effects on the material properties, during melting and cooling progression at different scales, will also be presented. Finally, the applications of the integrated numerical modelling and the material development for the digital manufacturing of welding, is discussed with references to typical application cases such as sensors (thermocouples), energy (heat exchanger) and automotive structures (duplex steel structures).

Keywords: computer modelling, droplet formation, material distortion, materials forming, welding

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Authors: Simiksha Balkissoon, Jerome Andrew, Bruce Sithole

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Approximately half of the wood processed in the Forestry, Timber, Pulp and Paper (FTPP) sector is accumulated as waste. The concept of a “green economy” encourages industries to employ revolutionary, transformative technologies to eliminate waste generation by exploring the development of new value chains. The transition towards an almost paperless world driven by the rise of digital media has resulted in a decline in traditional paper markets, prompting the FTTP sector to reposition itself and expand its product offerings by unlocking the potential of value-adding opportunities from renewable resources such as wood to generate revenue and mitigate its environmental impact. The production of valuable products from wood waste such as sawdust has been extensively explored in recent years. Wood components such as lignin, cellulose and hemicelluloses, which can be extracted selectively by chemical processing, are suitable candidates for producing numerous high-value products. In this study, a novel approach to produce high-value cellulose products, such as dissolving wood pulp (DWP), from sawdust was developed. DWP is a high purity cellulose product used in several applications such as pharmaceutical, textile, food, paint and coatings industries. The proposed approach demonstrates the potential to eliminate several complex processing stages, such as pulping and bleaching, which are associated with traditional commercial processes to produce high purity cellulose products such as DWP, making it less chemically energy and water-intensive. The developed process followed the path of experimentally designed lab tests evaluating typical processing conditions such as residence time, chemical concentrations, liquid-to-solid ratios and temperature, followed by the application of suitable purification steps. Characterization of the product from the initial stage was conducted using commercially available DWP grades as reference materials. The chemical characteristics of the products thus far have shown similar properties to commercial products, making the proposed process a promising and viable option for the production of DWP from sawdust.

Keywords: biomass, cellulose, chemical treatment, dissolving wood pulp

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Authors: Andrew Freiburger, Sergi Molins

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Freshwater is a vital resource; yet, the supply of clean freshwater is diminishing as the consequence of melting snow and ice from global warming, pollution from industry, and an increasing demand from human population growth. The unsustainable trajectory of diminishing water resources is projected to jeopardize water security for billions of people in the 21st century. Membrane desalination technologies may resolve the growing discrepancy between supply and demand by filtering arbitrary feed water into a fraction of renewable, clean water and a fraction of highly concentrated brine. The leading hindrance of membrane desalination is fouling, whereby the highly concentrated brine solution encourages micro-organismal colonization and/or the precipitation of occlusive minerals (i.e. scale) upon the membrane surface. Thus, an understanding of brine formation is necessary to mitigate membrane fouling and to develop efficacious desalination technologies that can bolster the supply of available freshwater. This study presents a reactive transport simulation of brine formation and scale deposition during reverse osmosis (RO) desalination. The simulation conceptually represents the RO module as a one-dimensional domain, where feed water directionally enters the domain with a prescribed fluid velocity and is iteratively concentrated in the immobile layer of a dual porosity model. Geochemical PHREEQC code numerically evaluated the conceptual model with parameters for the BW30-400 RO module and for real water feed sources – e.g. the Red and Mediterranean seas, and produced waters from American oil-wells, based upon peer-review data. The presented simulation is computationally simpler, and hence less resource intensive, than the existent and more rigorous simulations of desalination phenomena, like TOUGHREACT. The end-user may readily prepare input files and execute simulations on a personal computer with open source software. The graphical results of fouling-potential and brine characteristics may therefore be particularly useful as the initial tool for screening candidate feed water sources and/or informing the selection of an RO module.

Keywords: desalination, PHREEQC, reactive transport, scaling

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Authors: Shahnam Behnam Malekzadeh, Ian Kerr, Tyson Kaempffer, Teague Harper, Andrew Watson

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The Site C Hydroelectric dam is currently being constructed in north-eastern British Columbia on sub-horizontal sedimentary strata that dip approximately 15 meters from one bank of the Peace River to the other. More than 615 pressure sensors (Vibrating Wire Piezometers) have been installed on bedding planes (BPs) since construction began, with over 80 more planned before project completion. These pressure measurements are essential to monitor the stability of the rock foundation during and after construction and for dam safety purposes. BPs are identified by their clay gouge infilling, which varies in thickness from less than 1 to 20 mm and can be challenging to identify as the core drilling process often disturbs or washes away the gouge material. Without the use of depth predictions from nearby boreholes, stratigraphic markers, and downhole geophysical data, it is difficult to confidently identify BP targets for the sensors. In this paper, a Case-Based Reasoning (CBR) method was used to develop an empirical model called the Bedding Plane Elevation Prediction (BPEP) to help geologists and geotechnical engineers to predict geological features and bedding planes at new locations in a fast and accurate manner. To develop CBR, a database was developed based on 64 pressure sensors already installed on key bedding planes BP25, BP28, and BP31 on the Right Bank, including bedding plane elevations and coordinates. Thirteen (20%) of the most recent cases were selected to validate and evaluate the accuracy of the developed model, while the similarity was defined as the distance between previous cases and recent cases to predict the depth of significant BPs. The average difference between actual BP elevations and predicted elevations for above BPs was ±55cm, while the actual results showed that 69% of predicted elevations were within ±79 cm of actual BP elevations while 100% of predicted elevations for new cases were within ±99cm range. Eventually, the actual results will be used to develop the database and improve BPEP to perform as a learning machine to predict more accurate BP elevations for future sensor installations.

Keywords: case-based reasoning, geological feature, geology, piezometer, pressure sensor, core logging, dam construction

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Authors: Stefan Kurbatfinski, Aliyah Dosani, Andrew F. Hayes, Deborah Dewey, Nicole Letourneau

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Background: Maternal adverse childhood experiences (ACEs) have been associated with internalizing and externalizing behavioral problems in preschool children. However, little is known about the influence of maternal adult attachment patterns on this association. Further, potential moderation by maternal mental health, maternal social support, or child sex is poorly understood. Therefore, this study examined associations between 1) maternal ACEs and preschool children’s behavioural problems, with mediation through maternal attachment patterns and moderation by maternal mental health, maternal social support, and child sex; and 2) maternal attachment patterns and children’s behavioural problems, with mediation through maternal mental health and social support and moderation by child sex. Methods: This secondary analysis used data (n=625) from a high socioeconomic, longitudinally prospective cohort (Alberta Pregnancy Outcomes and Nutrition). Child behaviour (BASC-2) and maternal adult attachment (ECR-Q) were measured at five years of child age, maternal ACEs (ACEs Questionnaire) at around 12 months, and maternal mental health (CESD and SCL-90-R) and social support (SSQ) across various prenatal and postnatal time points. All moderation and mediation analyses occurred through RStudio using PROCESS, interpreting significant interactions through Johnson-Neyman plots. Findings: Maternal ACEs interacted with maternal anxiety symptoms to predict both behavioural problems (pexternalizing=0.007; pinternalizing=0.0159). An indirect pathway via dismissive attachment was moderated by maternal social support ([0.0058, 0.0596]). Attachment patterns predicted all behavioural problems (p<0.05) and interacted with maternal anxiety symptoms to predict internalizing behaviours among male children ([0.0321, 0.1307]; [0.0321, 0.1291]). Interpretation: Maternal attachment patterns may predict children’s behavioural problems more than ACEs. Social support interventions may not always be beneficial for highly dismissively attached mothers. Implications for policy and child health include mandatory sex and gender education for teachers; assessing attachment patterns prior to recommending social support as an intervention; and anxiety-focused interventions for mothers in higher socioeconomic populations.

Keywords: maternal adverse childhood experiences, internalizing behaviours, externalizing behaviours, mediators and moderators, attachment patterns, child health

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Authors: Mariia Timofeeva, Andrew Ooi, Eric K. W. Poon, Peter Barlis

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Atherosclerotic plaque build-up, commonly known as stenosis, limits blood flow and hence oxygen and nutrient supplies to the heart muscle. Thus, assessment of its severity is of great interest to health professionals. Numerical simulation of the fractional flow reserve (FFR) has proved to be well correlated with invasively measured FFR used for physiological assessment of the severity of coronary stenosis in arteries. Atherosclerosis may impact the diseased artery in several locations causing serial stenoses, which is a complicated subset of coronary artery disease that requires careful treatment planning. However, hemodynamic of the serial sequential stenoses in coronary arteries has not been extensively studied. The hemodynamics of the serial stenoses is complex because the stenoses in the series interact and affect the flow through each other. To address this, serial stenoses in a 3.4 mm left anterior descending (LAD) artery are examined in this study. Two diameter stenoses (DS) are considered, 30 and 50 percent of the reference diameter. Serial stenoses configurations are divided into three groups based on the order of the stenoses in the series, spacing between them, and deviation of the stenoses’ symmetry (eccentricity). A patient-specific pulsatile waveform is used in the simulations. Blood flow within the stenotic artery is assumed to be laminar, Newtonian, and incompressible. Results for the FFR are reported. Based on the simulation results, it can be deduced that the larger drop in pressure (smaller value of the FFR) is expected when the percentage of the second stenosis in the series is bigger. Varying the distance between the stenoses affects the location of the maximum drop in the pressure, while the minimal FFR in the artery remains unchanged. Eccentric serial stenoses are characterized by a noticeably larger decrease in pressure through the stenoses and by the development of the chaotic flow downstream of the stenoses. The largest drop in the pressure (about 4% difference compared to the axisymmetric case) is obtained for the serial stenoses, where both the stenoses are highly eccentric with the centerlines deflected to the different sides of the LAD. In conclusion, varying configuration of the sequential serial stenoses results in a different distribution of FFR through the LAD. Results presented in this study provide insight into the clinical assessment of the severity of the coronary serial stenoses, which is proved to depend on the relative position of the stenoses and the deviation of the stenoses’ symmetry.

Keywords: computational fluid dynamics, coronary artery, fractional flow reserve, serial stenoses

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Authors: Evelyn Marie Richmond, Andrew McBride, Chris Johnston, John Marley

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Background: Good quality patient information resources for orthognathic treatment help to reinforce information delivered during the initial consultation and help patients make informed decisions about their care. The Consultant Orthodontists and a Dental Core Trainee noted limited patient engagement with the British Orthodontic Society (BOS) 'Your Jaw Surgery' online resources and that the existing BOS patient information leaflet (PIL) could be customised and developed to meet local requirements. Aim: The quality improvement project (QIP) aimed to improve patients' understanding of orthognathic treatment by ensuring at least 90% of patients had read the new in-house patient information leaflet (PIL) and a minimum of 50% of patients had accessed the British Orthodontic Society (BOS) 'Your Jaw Surgery' online resources before attending the joint orthognathic multidisciplinary clinic by June 2023. Methods: The QIP was undertaken in the orthodontic department of the School of Dentistry, Belfast. Data was collected prospectively during a 6-month period from January 2023 to June 2023 over 3 Plan, Do, Study, Act (PDSA) cycles. Suitable patients were identified at consultant orthodontic new patient clinics. Following initial consultation for orthognathic treatment, patients were contacted to complete a patient questionnaire. Design: The change ideas were a poster with a QR code directing patients to the BOS 'Your Jaw Surgery' website in consultation areas and a new in-house PIL with a QR code directing patients to the BOS 'Your Jaw Surgery' website. Results: In PDSA cycle 1, 86.7% of patients were verbally directed to the BOS 'Your Jaw Surgery' website, and 53.3% accessed the online resources after their initial consultation. Although 100% of patients reported reading the existing PIL, only 64.3% felt it discussed the risks of orthognathic treatment in sufficient detail. By PDSA cycle 3, 100% of patients reported being directed to the BOS 'Your Jaw Surgery' website, however, only 58.3% engaged with the website. 100% of patients who read the new PIL felt that it discussed the risks of orthognathic treatment in sufficient detail. Conclusion: The slight improvement in access to the BOS 'Your Jaw Surgery' website shows that patients do not necessarily choose to access information online despite its availability. The uptake of the new PIL was greater than reported patient engagement with the BOS 'Your Jaw Surgery' website, which indicates patients still value written information despite the availability of online resources.

Keywords: orthognathic surgery, patient information resources, quality improvement project, risks

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Authors: Jiyoung Lee, Andrew D. Gershoff, Jerry Jisang Han

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Most extant research on consumer privacy concerns and their willingness to share personal data has focused on contextual factors (e.g., types of information collected, type of compensation) that lead to consumers’ personal information disclosure. Unfortunately, the literature lacks a clear understanding of how consumers’ incidental psychological needs may influence consumers’ decisions to share their personal information with companies or brands. In this research, we investigate how social exclusion, which is an increasing societal problem, especially since the onset of the COVID-19 pandemic, leads to increased information disclosure intentions for consumers. Specifically, we propose and find that when consumers become socially excluded, their desire for social connection increases, and this desire leads to a greater willingness to disclose their personal information with firms. The motivation to form and maintain interpersonal relationships is one of the most fundamental human needs, and many researchers have found that deprivation of belongingness has negative consequences. Given the negative effects of social exclusion and the universal need to affiliate with others, people respond to exclusion with a motivation for social reconnection, resulting in various cognitive and behavioral consequences, such as paying greater attention to social cues and conforming to others. Here, we propose personal information disclosure as another form of behavior that can satisfy such social connection needs. As self-disclosure can serve as a strategic tool in creating and developing social relationships, those who have been socially excluded and thus have greater social connection desires may be more willing to engage in self-disclosure behavior to satisfy such needs. We conducted four experiments to test how feelings of social exclusion can influence the extent to which consumers share their personal information with brands. Various manipulations and measures were used to demonstrate the robustness of our effects. Through the four studies, we confirmed that (1) consumers who have been socially excluded show greater willingness to share their personal information with brands and that (2) such an effect is driven by the excluded individuals’ desire for social connection. Our findings shed light on how the desire for social connection arising from exclusion influences consumers’ decisions to disclose their personal information to brands. We contribute to the consumer disclosure literature by uncovering a psychological need that influences consumers’ disclosure behavior. We also extend the social exclusion literature by demonstrating that exclusion influences not only consumers’ choice of products but also their decision to disclose personal information to brands.

Keywords: consumer-brand relationship, consumer information disclosure, consumer privacy, social exclusion

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Authors: Andrew Wee

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As a result of the Italian Independence Wars starting in 1848, Italy began to change through unification. People gradually moved away from some of their traditional practices and values, such as the long-held belief that women were inferior to men, as part of the Risorgimento. Italians began to take interest in opera as a form of emotional release. As opera became more popular and prominent in their culture, it aided in the dissemination of ideas, especially stimulating the spread of imperialism, in the late 19th century, as Italy began extending its presence to other countries. In order to collect the information needed to analyze Italy’s foreign presence, it was necessary to consult texts concerning the culture of the Risorgimento. These texts included primary sources from operatic composers and contemporary recorded accounts. Letters from Giuseppe Verdi, a leader in opera during the Risorgimento, have been scrutinized for indications of popular attitudes of the time. The cultural context of the Risorgimento is essential to understanding the Italian motives and attitudes towards the outside world. On the more political side, research has also entailed the study of historical data of general laws, policies, and their purposes concerning geopolitical boundaries and foreign affairs, such as Edward Said’s thesis on Orientalism. By establishing these two characteristics of Italy, the paper will thoroughly illustrate Italy’s presence in foreign affairs. Texts have been searched with the intent of using information that reveals Italian attitudes toward exotic countries to determine whether their demeanor was positive or condescending. Motives behind sources have been interpreted in context in order to form a complete picture of the Italian sentiment towards foreigners. Additionally, research pertaining to Italian nationalism and imperialism such as song and literature has been used. The primary form of research has been the division of sources that are culturally based and those that are political in nature. Opera had always been developing since its creation in the 17th century, and in the 19th century, the bel canto movement revolutionized opera and its role in Italian society. This paper uses evidence that popular sentiment was influenced by opera to support the belief that the evolution of opera was as a result of the nationalist sentiment, and in turn fueled the cultural movement known as the Risorgimento. In this way, opera proceeded to affect Italian culture by spreading the idea of imperialism.

Keywords: opera, Italian unification, music history, imperialism

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Authors: Christian Skowronski, Andrew Shanholtzer, Brent Yelton, Muayad Almahariq, Daniel J. Krauss

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Prostate cancer has the third highest incidence rate and is the second leading cause of cancer death for men in the United States. Of the diagnostic tools available for intermediate-risk prostate cancer, magnetic resonance imaging (MRI) provides superior soft tissue delineation serving as a valuable tool for both diagnosis and treatment planning. Currently, there is minimal data regarding the practical utility of MRI for evaluation of intermediate-risk prostate cancer. As such, the National Comprehensive Cancer Network’s guidelines indicate MRI as optional in intermediate-risk prostate cancer evaluation. This project aims to elucidate whether MRI affects radiation treatment decisions for intermediate-risk prostate cancer. This was a retrospective study evaluating 210 patients with intermediate-risk prostate cancer, treated with definitive radiotherapy at our institution between 2019-2020. NCCN risk stratification criteria were used to define intermediate-risk prostate cancer. Patients were divided into two groups: those with pretreatment prostate MRI, and those without pretreatment prostate MRI. We compared the use of external beam radiotherapy, brachytherapy alone, brachytherapy boost, and androgen depravation therapy between the two groups. Inverse probability of treatment weighting was used to match the two groups for age, comorbidity index, American Urologic Association symptoms index, pretreatment PSA, grade group, and percent core involvement on prostate biopsy. Wilcoxon Rank Sum and Chi-squared tests were used to compare continuous and categorical variables. Of the patients who met the study’s eligibility criteria, 133 had a prostate MRI and 77 did not. Following propensity matching, there were no differences between baseline characteristics between the two groups. There were no statistically significant differences in treatments pursued between the two groups: 42% vs 47% were treated with brachytherapy alone, 40% vs 42% were treated with external beam radiotherapy alone, 18% vs 12% were treated with external beam radiotherapy with a brachytherapy boost, and 24% vs 17% received androgen deprivation therapy in the non-MRI and MRI groups, respectively. This analysis suggests that pretreatment MRI does not significantly impact radiation therapy or androgen deprivation therapy decisions in patients with intermediate-risk prostate cancer. Obtaining a pretreatment prostate MRI should be used judiciously and pursued only to answer a specific question, for which the answer is likely to impact treatment decision. Further follow up is needed to correlate MRI findings with their impacts on specific oncologic outcomes.

Keywords: magnetic resonance imaging, prostate cancer, definitive radiotherapy, gleason score 7

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Authors: Thea Freese, Michael Gille, Andrew Hursthouse, John Struthers

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Ship operators on the North and Baltic Sea have been experiencing increased political interest in marine environmental protection and cleaner vessel operations. Stricter legislation on SO2 and NOx emissions, ballast water management and other measures of protection are currently being phased in or will come into force in the coming years. These measures benefit the health of the marine environment, while increasing company’s operational costs. In times of excess shipping capacity and linked consolidation in the industry non-compliance with environmental rules is one way companies might hope to stay competitive with both intra- and inter-modal trade. Around 5-15% of industry participants are believed to neglect laws on vessel-source pollution willingly or unwillingly. Exploratory in-depth interviews conducted with 12 experts from various stakeholder groups informed the researchers about variables influencing compliance levels, including awareness and apprehension, willingness to comply, ability to comply and effectiveness of controls. Semi-structured expert interviews were evaluated using qualitative content analysis. A model of determinants of compliance was developed and is presented here. While most vessel operators endeavour to achieve full compliance with environmental rules, a lack of availability of technical solutions, expediency of implementation and operation and economic feasibility might prove a hindrance. Ineffective control systems on the other hand foster willing non-compliance. With respect to motivations, lacking time, lacking financials and the absence of commercial advantages decrease compliance levels. These and other variables were inductively developed from qualitative data and integrated into a model on environmental compliance. The outcomes presented here form part of a wider research project on economic effects of maritime environmental legislation. Research on determinants of compliance might inform policy-makers about actual behavioural effects of shipping companies and might further the development of a comprehensive legal system for environmental protection.

Keywords: compliance, marine environmental protection, exploratory qualitative research study, clean vessel operations, North and Baltic Sea area

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Authors: Franklin Chu Buh, Irene Ule Ngole Sumbele, Andrew I. R. Maas, Mathieu Motah, Jogi V. Pattisapu, Eric Youm, Basil Kum Meh, Firas H. Kobeissy, Kevin W. Wang, Peter J. A. Hutchinson, Germain Sotoing Taiwe

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Introduction: Studying TBI characteristics and their relation to outcomes can identify initiatives to improve TBI prevention and care. The objective of this study was to define the features and outcomes of TBI patients seen over a 1-year period in a level-I trauma center in Cameroon. Methods: Data on demographics, causes, injury mechanisms, clinical aspects, and discharge status were prospectively collected over a period of 12 months. The Glasgow Outcome Scale-Extended (GOSE) and the Quality of Life Questionnaire after Brain Injury (QoLIBRI) were used to evaluate outcomes 6-months after TBI. Categorical variables were described as frequencies and percentages. Comparisons between 2 categorical variables were done using Pearson's Chi-square test or Fisher's exact test. Results: A total of 160 TBI patients participated in the study. The age group 15-45 years (78%; 125) was most represented. Males were more affected (90%; 144). Low educational level was recorded in 122 (76%) cases. Road traffic incidents (RTI) were the main cause of TBI (85%), with professional bike riders being frequently involved (27%, 43/160). Assaults (7.5%) and falls (2.5%) represent the second and third most common causes of TBI in Cameroon, respectively. Only 15 patients were transported to the hospital by ambulance, and 14 of these were from a referring hospital. CT-imaging was performed in 78% (125/160) of cases intracranial traumatic abnormality was identified in 77/125 (64%) cases. Financial constraints were the main reason for not performing a CT scan on 35 patients. A total of 46 (33%) patients were discharged against medical advice (DAMA) due to financial constraints. Mortality was 14% (22/160) but disproportionately high in patients with severe TBI (46%). DAMA had poor outcomes with QoLIBRI. Only 4 patients received post-injury physiotherapy services. Conclusion: TBI in Cameroon mainly results from RTIs and commonly affects young adult males, and low educational or socioeconomic status and commercial bike riding appear to be predisposing factors. Lack of pre-hospital care, financial constraints limiting both CT-scanning and medical care, and lack of acute physiotherapy services likely influenced care and outcomes adversely.

Keywords: characteristics, traumatic brain injury, outcome, disparities in care, prospective study

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Authors: Martyn Queen, Diane Crone, Andrew Parker, Saul Bloxham

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Rationale: There is a growing body of evidence that supports the use of physical activity during and after cancer treatment. However, activity levels for patients remain low. As more cancer patients are treated successfully, and treatment costs continue to escalate, physical activity may be a promising adjunct to a person-centred healthcare approach to recovery. Aim: The aim was to further understand how physical activity may enhance the recovery process for a group of mixed-site cancer patients. Objectives: The research investigated longitudinal changes in physical activity and perceived the quality of life between two and six month’s post-exercise interventions. It also investigated support systems that enabled patients to sustain these perceived changes. Method: The respondent cohort comprised 14 mixed-site cancer patients aged 43-70 (11 women, 3 men), who participated in a two-phase physical activity intervention that took place at a university in the South West of England. Phase 1 consisted of an eight-week structured physical activity programme; Phase 2 consisted of four months of non-supervised physical activity. Semi-structured interviews took place three times over six months with each participant. Grounded theory informed the data collection and analysis which, in turn, facilitated theoretical development. Findings: Our findings propose three theories on the impact of physical activity for recovering cancer patients: 1) Knowledge gained through a structured exercise programme can enable recovering cancer patients to independently sustain physical activity to four-month follow-up. 2) Sustaining physical activity for six months promotes positive changes in the quality of life indicators of chronic fatigue, self-efficacy, the ability to self-manage and energy levels. 3) Peer support from patients facilitates adherence to a structured exercise programme and support from a spouse, or life partner facilitates independently sustained physical activity to four-month follow-up. Conclusions: This study demonstrates that qualitative research can provide an evidence base that could be used to support future care plans for cancer patients. Findings also demonstrate that a physical activity intervention can be effective at helping cancer patients recover from the side effects of their treatment, and recommends that physical activity should become an adjunct therapy alongside traditional cancer treatments.

Keywords: physical activity, health, cancer recovery, quality of life, support systems, qualitative, grounded theory, person-centred healthcare

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Authors: Kim Kennedy, Daren Gibson, Stephanie Flukes, Chandra Diwakarla, Lisa Spalding, Leanne Pilkington, Andrew Redfern

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Introduction: Head and neck cancers (HNC) are often associated with the development of non-HNC primaries, as the risk factors that predispose patients to HNC are often risk factors for other cancers. Aim: We sought to evaluate whether there was an increased risk of smoking and alcohol-related cancers and also other cancers in HNC patients and to evaluate whether there is a difference between the rates of non-HNC primaries in Aboriginal compared with non-Aboriginal HNC patients. Methods: We performed a retrospective cohort analysis of 320 HNC patients from a single center in Western Australia, identifying 80 Aboriginal and 240 non-Aboriginal patients matched on a 1:3 ratio by sites, histology, rurality, and age. We collected data on the patient characteristics, tumour features, treatments, outcomes, and past and subsequent HNCs and non-HNC primaries. Results: In the overall study population, there were 86 patients (26.9%) with a metachronous or synchronous non-HNC primary. Non-HNC primaries were actually significantly more common in the non-Aboriginal population compared with the Aboriginal population (30% vs. 17.5%, p=0.02); however, half of these were patients with cutaneous squamous or basal cell carcinomas (cSCC/BCC) only. When cSCC/BCCs were excluded, non-Aboriginal patients had a similar rate as Aboriginal patients (16.7% vs. 15%, p=0.73). There were clearly more cSCC/BCCs in non-Aboriginal patients compared with Aboriginal patients (16.7% vs. 2.5%, p=0.001) and more patients with melanoma (2.5% vs. 0%, p value not significant (p=NS). Rates of most cancers were similar between non-Aboriginal and Aboriginal patients, including prostate (2.9% vs. 3.8%), colorectal (2.9% vs. 2.5%), kidney (1.2% vs. 1.2%), and these rates appeared comparable to Australian Age Standardised Incidence Rates (ASIR) in the general community. Oesophageal cancer occurred at double the rate in Aboriginal patients (3.8%) compared with non-Aboriginal patients (1.7%), which was far in excess of ASIRs which estimated a lifetime risk of 0.59% in the general population. Interestingly lung cancer rates did not appear to be significantly increased in our cohort, with 2.5% of Aboriginal patients and 3.3% of non-Aboriginal patients having lung cancer, which is in line with ASIRs which estimates a lifetime risk of 5% (by age 85yo). Interestingly the rate of Glioma in the non-Aboriginal population was higher than the ASIR, with 0.8% of non-Aboriginal patients developing Glioma, with Australian averages predicting a 0.6% lifetime risk in the general population. As these are small numbers, this finding may well be due to chance. Unsurprisingly, second HNCs occurred at an increased incidence in our cohort, in 12.5% of Aboriginal patients and 11.2% of non-Aboriginal patients, compared to an ASIR of 17 cases per 100,000 persons, estimating a lifetime risk of 1.70%. Conclusions: Overall, 26.9% of patients had a non-HNC primary. When cSCC/BCCs were excluded, Aboriginal and non-Aboriginal patients had similar rates of non-HNC primaries, although non-Aboriginal patients had a significantly higher rate of cSCC/BCCs. Aboriginal patients had double the rate of oesophageal primaries; however, this was not statistically significant, possibly due to small case numbers.

Keywords: head and neck cancer, synchronous and metachronous primaries, other primaries, Aboriginal

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Authors: Daniel R. McDougall, Martin D. de Jonge, Gordon M. Miskelly, Duncan J. McGillivray, Andrew G. Jeffs

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The chelating agent ethylenediaminetetraacetic acid (EDTA) is commonly added as a cure-all to seawater in aquaculture hatcheries around the world to reduce heavy metal toxicity, significantly improve the survival of larval shellfish, and to therefore improve the overall production efficiency of the aquaculture industry. However, EDTA is not a biodegradable chemical and is considered to be a persistent organic pollutant, which will accumulate in the environment over time. This makes the use of EDTA unsustainable environmentally, and therefore alternatives should be considered. Ethylenediaminedisuccinic acid (EDDS) is a biodegradable alternative to EDTA with very similar metal chelation properties. This study investigates the effect of EDTA and EDDS at two different concentrations, on metal concentrations found within developing New Zealand green-lipped mussel (Perna canaliculus) larvae. P. canaliculus is New Zealand’s main shellfish aquaculture species, providing a major export for New Zealand’s economy, with excellent potential for increased production in the near future. It is well known that the early stages of bivalve development are the most vulnerable to metal toxicity and P. canaliculus is no exception. The commercially used concentration (12 µmol L⁻¹) of EDTA added to P. canaliculus larval rearing tanks often increases the yield of D-larvae by over 80%. This concentration of EDTA and EDDS will be tested in this study, along with a lower concentration (3 µmol L⁻¹). After 48 hours of larval development, the D-larvae will be analyzed for heavy metal content with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and heavy metal distribution with synchrotron X-ray Fluorescence Microscopy (XFM). In this study, we found that EDDS also improves the yield of P. canaliculus larvae and could be a viable alternative to EDTA in aquaculture. Furthermore, results suggest a higher concentration of chelating agent is more effective for improving the yield of developing P. canaliculus larvae. Metals with significant differences in concentration with the addition of EDTA were Cr, Cu, Zn, Cd and Pb (P < 0.05). We observed for the first time to the author’s best knowledge, metal distribution within 100 µm P. canaliculus D-larvae using synchrotron XFM and found changes in the distribution of metals with the addition of EDTA. XFM also has the potential to provide information about the chemical state of the metals within mussel larvae. This research provides greater insight into the reasons for the effectiveness of adding the chelating agent to aquaculture culture water, and a more environmentally conscious alternative to the currently used EDTA, which could be extremely valuable for the aquaculture industry.

Keywords: EDDS, EDTA, heavy metals, P. canaliculus, toxicity, water treatment

Procedia PDF Downloads 235

Authors: Neil Bar, Andrew Heweston

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Probability of failure (PF) often appears alongside factor of safety (FS) in design acceptance criteria for rock slope, underground excavation and open pit mine designs. However, the design acceptance criteria generally provide no guidance relating to how PF should be calculated for homogeneous and heterogeneous rock masses, or what qualifies a ‘reasonable’ PF assessment for a given slope design. Observational and kinematic methods were widely used in the 1990s until advances in computing permitted the routine use of numerical modelling. In the 2000s and early 2010s, PF in numerical models was generally calculated using the point estimate method. More recently, some limit equilibrium analysis software offer statistical parameter inputs along with Monte-Carlo or Latin-Hypercube sampling methods to automatically calculate PF. Factors including rock type and density, weathering and alteration, intact rock strength, rock mass quality and shear strength, the location and orientation of geologic structure, shear strength of geologic structure and groundwater pore pressure influence the stability of rock slopes. Significant engineering and geological judgment, interpretation and data interpolation is usually applied in determining these factors and amalgamating them into a geotechnical model which can then be analysed. Most factors are estimated ‘approximately’ or with allowances for some variability rather than ‘exactly’. When it comes to numerical modelling, some of these factors are then treated deterministically (i.e. as exact values), while others have probabilistic inputs based on the user’s discretion and understanding of the problem being analysed. This paper discusses the importance of understanding the key aspects of slope design for homogeneous and heterogeneous rock masses and how they can be translated into reasonable PF assessments where the data permits. A case study from a large open pit gold mine in a complex geological setting in Western Australia is presented to illustrate how PF can be calculated using different methods and obtain markedly different results. Ultimately sound engineering judgement and logic is often required to decipher the true meaning and significance (if any) of some PF results.

Keywords: probability of failure, point estimate method, Monte-Carlo simulations, sensitivity analysis, slope stability

Procedia PDF Downloads 208

Authors: Sittampalam Manoharan, Gary Chai, Sanaul Chowdhury, Andrew Golding

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The primary objective of this paper is to present a simplified approach to develop the structural deterioration model using traffic speed deflectometer data for flexible pavements. Maintaining assets to meet functional performance is not economical or sustainable in the long terms, and it would end up needing much more investments for road agencies and extra costs for road users. Performance models have to be included for structural and functional predicting capabilities, in order to assess the needs, and the time frame of those needs. As such structural modelling plays a vital role in the prediction of pavement performance. A structural condition is important for the prediction of remaining life and overall health of a road network and also major influence on the valuation of road pavement. Therefore, the structural deterioration model is a critical input into pavement management system for predicting pavement rehabilitation needs accurately. The Traffic Speed Deflectometer (TSD) is a vehicle-mounted Doppler laser system that is capable of continuously measuring the structural bearing capacity of a pavement whilst moving at traffic speeds. The device’s high accuracy, high speed, and continuous deflection profiles are useful for network-level applications such as predicting road rehabilitations needs and remaining structural service life. The methodology adopted in this model by utilizing time series TSD maximum deflection (D0) data in conjunction with rutting, rutting progression, pavement age, subgrade strength and equivalent standard axle (ESA) data. Then, regression analyses were undertaken to establish a correlation equation of structural deterioration as a function of rutting, pavement age, seal age and equivalent standard axle (ESA). This study developed a simple structural deterioration model which will enable to incorporate available TSD structural data in pavement management system for developing network-level pavement investment strategies. Therefore, the available funding can be used effectively to minimize the whole –of- life cost of the road asset and also improve pavement performance. This study will contribute to narrowing the knowledge gap in structural data usage in network level investment analysis and provide a simple methodology to use structural data effectively in investment decision-making process for road agencies to manage aging road assets.

Keywords: adjusted structural number (SNP), maximum deflection (D0), equant standard axle (ESA), traffic speed deflectometer (TSD)

Procedia PDF Downloads 151

Authors: Christopher Pullen

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This paper explores the significance of British cinema in the late 1950s and early 1960s as offering a renaissance of realist discourse, in the representation of everyday social issues. Offering a rejection of Hollywood cinema and the superficially of the middle classes, these ‘kitchen sink dramas’ often set within modest and sometimes squalid domestic and social environments, focused on the political struggle of the disenfranchised examining poverty, the oppressed and the outsider. While films like Look Back in Anger and Room at the Top looked primarily at male heterosexual subjectivity, films like A Taste of Honey and Victim focused on female and queer male narratives. Framing the urban landscape as a discursive architectural arena, representing basic living conditions and threatening social worlds, these iconic films established new storytelling processes for the outsider. This paper examines this historical context foregrounding the contemporary films Beautiful Thing (Hettie Macdonald, 1996), Weekend (Andrew Haigh, 2011) and Pride (Marcus Warchus, 2014), while employing the process of textual analysis in relation to theories of affect, defined by writers such as Lisa U. Marks and Sara Ahmed. Considering both romance narratives and public demonstrations of unity, where the queer ‘affective’ body is placed within architectural and social space, Beautiful Thing tells the story of gay male teenagers falling in love despite oppression from family and school, Weekend examines a one-night stand between young gay men and the unlikeliness of commitment, but the drive for sensitivity, and Pride foregrounds an historical relationship between queer youth activists and the miner’s union, who were on strike between 1984-5. These films frame the queer ‘affective’ body within politicized public space, evident in lower class men’s working clubs, tenement housing and brutal modernist tower blocks, focusing on architectural features such as windows, doorways and staircases, relating temporality, desire and change. Through such an examination a hidden history of gay male performativity is revealed, framing the potential of contemporary cinema to focus on the context of the outsider in encouraging social change.

Keywords: queer, affect, cinema, architecture, life chances

Procedia PDF Downloads 360

Authors: Robnier Reyes, Andrew J. P. Marques, Joel Ramjist, Chris R. Pasarikovski, Victor X. D. Yang

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Over the past three decades, surgical robotic systems have demonstrated their ability to improve surgical outcomes. The LBR Med is a collaborative robotic arm that is meant to work with a surgeon to streamline surgical workflow. It has 7 degrees of freedom and thus can be easily oriented. Position and torque sensors at each joint allow it to maintain a position accuracy of 150 µm with real-time force and torque feedback, making it ideal for complex surgical procedures. Spinal fusion procedures involve the placement of as many as 20 pedicle screws, requiring a great deal of accuracy due to proximity to the spinal canal and surrounding vessels. Any deviation from intended path can lead to major surgical complications. Assistive surgical robotic systems are meant to serve as collaborative devices easing the workload of the surgeon, thereby improving pedicle screw placement by mitigating fatigue related inaccuracies. Moreover, robotic spinal systems have shown marked improvements over conventional freehanded techniques in both screw placement accuracy and fusion quality and have greatly reduced the need for screw revision, intraoperatively and post-operatively. However, current assistive spinal fusion robots, such as the ROSA Spine, are limited in functionality to positioning surgical instruments. While they offer a small degree of improvement in pedicle screw placement accuracy, they do not alleviate surgeon fatigue, nor do they provide real-time force and torque feedback during screw insertion. We propose a semi-autonomous surgical robot workflow for spinal fusion where the surgeon guides the robot to its initial position and orientation, and the robot drives the pedicle screw accurately into the vertebra. Here, we demonstrate feasibility by inserting pedicle screws into ex-vivo bovine rib bone. The robot monitors position, force and torque with respect to predefined values selected by the surgeon to ensure the highest possible spinal fusion quality. The workflow alleviates the strain on the surgeon by having the robot perform the screw placement while the ability to monitor the process in real-time keeps the surgeon in the system loop. The approach we have taken in terms of level autonomy for the robot reflects its ability to safely collaborate with the surgeon in the operating room without external navigation systems.

Keywords: ex vivo bovine bone, pedicle screw, surgical robot, surgical workflow

Procedia PDF Downloads 169

Authors: Guler D. Uzel, Andrew G. Parker, Robert L. Mach, Adly Abd-Alla

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Several tsetse fly species (Diptera: Glossinidae) in natural or colonized populations can be infected with the salivary gland hypertrophy virus (SGHV), a circular dsDNA virus (Hytrosaviridae). The virus infection is mainly asymptomatic but, in some species under certain conditions, the infection can produce salivary gland hypertrophy (SGH) symptoms. In the laboratory colonized tsetse, flies with SGH have reduced fertility, which negatively affects colony performance. Therefore, a high prevalence of SGH in insect mass rearing represents a major challenge for tsetse control using the sterile insect technique. The main objective of this study is to analyze the impact of Glossina pallidipes SGHV infection in various tsetse species on mortality and productivity and its impact on the symbiotic bacteria. Hypertropied salivary glands (SG) were collected from G. pallidipes into phosphate buffered saline (PBS) to prepare suspension; 2 µl aliquots were injected into adults of several tsetse species (G. pallidipes (Gp), G. p. gambiensis (Gpg), G. brevipalpis (Gb), G. morsitans morsitans (Gmm), G. morsitans centralis (Gmc) and G. fuscipes (Gf)) and the change in virus and symbiont titers were analyzed using qPCR. The development of SGH in the F1 was detected by dissection 10 days after emergence and virus infection was confirmed by PCR. The impact of virus infection on fly mortality and productivity was recorded. 2 µl aliquots were also injected into 3rd instar larvae of the different species and the adult SGs assayed by PCR for virus. Virus positive SGs from each species were homogenized in PBS and pooled within species for injection into larvae of the same species. Flies injected with PBS were used as control. Injecting teneral flies with SGHV caused increasing virus titer over time in all species but no SGH was detected. Dissection of the F1 also showed no development of SGH except in Gp (the homologous host). Injection of SGHV did not have any impact on the prevalence of the tsetse symbionts, but an increase in Sodalis titer was observed correlated with fly age regardless of virus infection. The virus infection had a negative impact on productivity and mortality. SGHV injection into larvae of the different species produced SGHV infected glands in the adults determined by PCR with a rate of 60%, 27%, 16%, 7% and 7% for Gp, Gf, Gpg, Gmm and Gmc, respectively. Virus positive SGs observed in the heterologous species were smaller than SGH found in Gp. No virus positive SG was detected by PCR in Gb and no SGH was observed in any adults except in Gp. Injecting virus suspension from the virus positive SGs into conspecific larvae did not produce any adults with infected SGs (except in Gp). SGHV can infect all tested tsetse species. Although the virus can infect and increase in titer in other tsetse species and affect fly mortality and productivity, no vertical virus transmission was observed in other tsetse species with might indicate a transmission barrier in these species, and virus collected from flies injected as larvae was not infective by injection.

Keywords: DNA viruses, glossina, hytrosaviridae, symbiotic bacteria, tsetse

Procedia PDF Downloads 217

Authors: Vincent Andrew Cappellano

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In the early phases of critical infrastructure system design, translating distributed computing requirements to an architecture has risk given the multitude of approaches (e.g., cloud, edge, fog). In many systems, a single requirement for system uptime / availability is used to encompass the system’s intended operations. However, when architected systems may perform to those availability requirements only during normal operations and not during component failure, or during outages caused by adversary attacks on critical infrastructure (e.g., physical, cyber). System designers lack a structured method to evaluate availability requirements against candidate system architectures through deep degradation scenarios (i.e., normal ops all the way down to significant damage of communications or physical nodes). This increases risk of poor selection of a candidate architecture due to the absence of insight into true performance for systems that must operate as a piece of critical infrastructure. This research effort proposes a process to analyze critical infrastructure system availability requirements and a candidate set of systems architectures, producing a metric assessing these architectures over a spectrum of degradations to aid in selecting appropriate resilient architectures. To accomplish this effort, a set of simulation and evaluation efforts are undertaken that will process, in an automated way, a set of sample requirements into a set of potential architectures where system functions and capabilities are distributed across nodes. Nodes and links will have specific characteristics and based on sampled requirements, contribute to the overall system functionality, such that as they are impacted/degraded, the impacted functional availability of a system can be determined. A machine learning reinforcement-based agent will structurally impact the nodes, links, and characteristics (e.g., bandwidth, latency) of a given architecture to provide an assessment of system functional uptime/availability under these scenarios. By varying the intensity of the attack and related aspects, we can create a structured method of evaluating the performance of candidate architectures against each other to create a metric rating its resilience to these attack types/strategies. Through multiple simulation iterations, sufficient data will exist to compare this availability metric, and an architectural recommendation against the baseline requirements, in comparison to existing multi-factor computing architectural selection processes. It is intended that this additional data will create an improvement in the matching of resilient critical infrastructure system requirements to the correct architectures and implementations that will support improved operation during times of system degradation due to failures and infrastructure attacks.

Keywords: architecture, resiliency, availability, cyber-attack

Procedia PDF Downloads 109

Authors: Bonnie Clough, Tamara Ownsworth, Vladimir Estivill-Castro, Matt Stainer, Rene Hexel, Andrew Bulmer, Wendy Moyle, Allison Waters, David Neumann, Jayke Bennett

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The success of global vaccination programs is reliant on the uptake of vaccines to achieve herd immunity. Yet, many individuals do not obtain vaccines or venipuncture procedures when needed. Whilst health education may be effective for those individuals who are hesitant due to safety or efficacy concerns, for many of these individuals, the primary concern relates to blood or injection fear or phobia (BII). BII is highly prevalent and associated with a range of negative health impacts, both at individual and population levels. Exposure therapy is an efficacious treatment for specific phobias, including BII, but has high patient dropout and low implementation by therapists. Whilst virtual reality approaches exposure therapy may be more acceptable, they have similarly low rates of implementation by therapists and are often difficult to tailor to an individual client’s needs. It was proposed that a piloted robot may be able to adequately facilitate fear induction and be an acceptable approach to exposure therapy. The current study examined fear induction responses, acceptability, and feasibility of a piloted robot for BII exposure. A Nao humanoid robot was programmed to connect with a virtual reality head-mounted display, enabling live streaming and exploration of real environments from a distance. Thirty adult participants with BII fear were randomly assigned to robot-pilot or virtual reality exposure conditions in a laboratory-based fear exposure task. All participants also completed a computer-based two-dimensional exposure task, with an order of conditions counterbalanced across participants. Measures included fear (heart rate variability, galvanic skin response, stress indices, and subjective units of distress), engagement with a feared stimulus (eye gaze: time to first fixation and a total number of fixations), acceptability, and perceived treatment credibility. Preliminary results indicate that fear responses can be adequately induced via a robot-piloted platform. Further results will be discussed, as will implications for the treatment of BII phobia and other fears. It is anticipated that piloted robots may provide a useful platform for facilitating exposure therapy, being more acceptable than in-vivo exposure and more flexible than virtual reality exposure.

Keywords: anxiety, digital mental health, exposure therapy, phobia, robot, virtual reality

Procedia PDF Downloads 78

Authors: Nada R. Abuknesha, John P. Morgan, Andrew J. Searle

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Information regarding post-mortem interval (PMI) in criminal investigations is vital to establish a time frame when reconstructing events. PMI is defined as the time period that has elapsed between the occurrence of death and the discovery of the corpse. Adipocere, commonly referred to as ‘grave-wax’, is formed when post-mortem adipose tissue is converted into a solid material that is heavily comprised of fatty acids. Adipocere is of interest to forensic anthropologists, as its formation is able to slow down the decomposition process. Therefore, analysing the changes in the patterns of fatty acids during the early decomposition process may be able to estimate the period of burial, and hence the PMI. The current study concerned the investigation of the fatty acid composition and patterns in buried pig fat tissue. This was in an attempt to determine whether particular patterns of fatty acid composition can be shown to be associated with the duration of the burial, and hence may be used to estimate PMI. The use of adipose tissue from the abdominal region of domestic pigs (Sus-scrofa), was used to model the human decomposition process. 17 x 20cm piece of pork belly was buried in a shallow artificial grave, and weekly samples (n=3) from the buried pig fat tissue were collected over an 11-week period. Marker fatty acids: palmitic (C16:0), oleic (C18:1n-9) and linoleic (C18:2n-6) acid were extracted from the buried pig fat tissue and analysed as fatty acid methyl esters using the gas chromatography system. Levels of the marker fatty acids were quantified from their respective standards. The concentrations of C16:0 (69.2 mg/mL) and C18:1n-9 (44.3 mg/mL) from time zero exhibited significant fluctuations during the burial period. Levels rose (116 and 60.2 mg/mL, respectively) and fell starting from the second week to reach 19.3 and 18.3 mg/mL, respectively at week 6. Levels showed another increase at week 9 (66.3 and 44.1 mg/mL, respectively) followed by gradual decrease at week 10 (20.4 and 18.5 mg/mL, respectively). A sharp increase was observed in the final week (131.2 and 61.1 mg/mL, respectively). Conversely, the levels of C18:2n-6 remained more or less constant throughout the study. In addition to fluctuations in the concentrations, several new fatty acids appeared in the latter weeks. Other fatty acids which were detectable in the time zero sample, were lost in the latter weeks. There are several probable opportunities to utilise fatty acid analysis as a basic technique for approximating PMI: the quantification of marker fatty acids and the detection of selected fatty acids that either disappear or appear during the burial period. This pilot study indicates that this may be a potential semi-quantitative methodology for determining the PMI. Ideally, the analysis of particular fatty acid patterns in the early stages of decomposition could be an additional tool to the already available techniques or methods in improving the overall processes in estimating PMI of a corpse.

Keywords: adipocere, fatty acids, gas chromatography, post-mortem interval

Procedia PDF Downloads 132

Authors: Ahmed Elsayed, Andrew Shea, Nicolas Kelly, John Allison

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In northern European climates, domestic space heating and hot water represents a significant proportion of total primary total primary energy use and meeting these demands from a national electricity grid network supplied by renewable energy sources provides an opportunity for a significant reduction in EU CO₂ emissions. However, in order to adapt to the intermittent nature of renewable energy generation and to avoid co-incident peak electricity usage from consumers that may exceed current capacity, the demand for heat must be decoupled from its generation. Storage of heat within the fabric of dwellings for use some hours, or days, later provides a route to complete decoupling of demand from supply and facilitates the greatly increased use of renewable energy generation into a local or national electricity network. The integration of thermal energy storage into the building fabric for retrieval at a later time requires much evaluation of the many competing thermal, physical, and practical considerations such as the profile and magnitude of heat demand, the duration of storage, charging and discharging rate, storage media, space allocation, etc. In this paper, the authors report investigations of thermal storage in building fabric using concrete material and present an evaluation of several factors that impact upon performance including heating pipe layout, heating fluid flow velocity, storage geometry, thermo-physical material properties, and also present an investigation of alternative storage materials and alternative heat transfer fluids. Reducing the heating pipe spacing from 200 mm to 100 mm enhances the stored energy by 25% and high-performance Vacuum Insulation results in heat loss flux of less than 3 W/m², compared to 22 W/m² for the more conventional EPS insulation. Dense concrete achieved the greatest storage capacity, relative to medium and light-weight alternatives, although a material thickness of 100 mm required more than 5 hours to charge fully. Layers of 25 mm and 50 mm thickness can be charged in 2 hours, or less, facilitating a fast response that could, aggregated across multiple dwellings, provide significant and valuable reduction in demand from grid-generated electricity in expected periods of high demand and potentially eliminate the need for additional new generating capacity from conventional sources such as gas, coal, or nuclear.

Keywords: fabric integrated thermal storage, FITS, demand side management, energy storage, load shifting, renewable energy integration

Procedia PDF Downloads 166

Authors: Andrew Green, Jiaming Liu, Kellathur Srinivasan, Raymond Chua

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Introduction: The size of Singapore’s online health product (HP) market (e-commerce) is largely unknown. However, it is recognized that a large majority comes from overseas and thus, unregulated. As buying HP from unauthorized sources significantly compromises public health safety, understanding e-commerce users’ demographics and their perceptions on online HP purchasing becomes a pivotal first step to form a basis for recommendations in Singapore’s pharmacovigilance efforts. Objective: To assess the prevalence of online HP purchasing behaviour among Singaporean e-commerce users. Methodology: This is a cross-sectional study targeting Singaporean e-commerce users recruited from various local websites and online forums. Participants were not randomized into study arms but instead stratified by random sampling method based on participants’ age. A self-administered anonymous questionnaire was used to explore participants' demographics, online HP purchasing behaviour, knowledge and attitude. The association of different variables with online HP purchasing behaviour was analysed using logistic regression statistics. Main outcome measures: Prevalence of HP e-commerce users in Singapore (%) and variables that contribute to the prevalence (adjusted prevalent ratio). Results: The study recruited 372 complete and valid responses. The prevalence of online HP consumers among e-commerce users in Singapore is estimated to be 55.9% (1.7 million consumers). Online purchasing of complementary HP (46.9%) was the most prevalent, followed by medical devices (21.6%) and Western medicine (20.5%). Multivariate analysis showed that age is an independent variable that correlates with the likelihood of buying HP online. The prevalence of HP e-commerce users is highest in the 35-44 age group (64.1%) and lowest among the 16-24 age group (36.4%). The most bought HP through the internet are vitamins and minerals (21.5%), non-herbal (15.9%), herbal (13.9%), weight loss (8.7%) and sports (8.4%) supplements. While the top 3 products are distributed equally between the genders, there is a skew towards female respondents (12.4% in females vs. 4.9% in males) for weight loss supplements and towards males (13.2% in males vs. 3.7% in females) for sports supplements. Even though online consumers are in the younger age brackets, our study found that up to 72.0% of HP bought online are bought for others (buyer’s family and/or friends). Multivariate analysis showed a statistically significant association between purchasing HP through online means and the perceptions that 'internet is safe' (adjusted Prevalence Ratio=1.15, CI 1.03-1.28), 'buying HP online is time saving' (PR=1.17, CI 1.01-1.36), and 'recognition of HP brand' (PR=1.21 CI 1.06-1.40). Conclusions: This study has provided prevalence data for online HP market in Singapore, and has allowed the country’s regulatory body to formulate a targeted pharmacovigilance approach to this growing problem.

Keywords: e-commerce, pharmaceuticals, pharmacovigilance, Singapore

Procedia PDF Downloads 364

Authors: Hung-Chih Hsu, Pey-Jium Chang, Ching-Hsein Chen, Jer-Liang Andrew Yeh

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Osteoarthritis (OA) is a common disorder in rehabilitation clinic. The main characteristics include joint pain, localized tenderness and enlargement, joint effusion, cartilage destruction, loss of adhesion of perichondrium, synovium hyperplasia. Synoviocytes inflammation might be a cause of local tenderness and effusion. Inflammation cytokines might also play an important role in joint pain, cartilage destruction, decrease adhesion of perichondrium to the bone. Treatments of osteoarthritis include non-steroid anti-inflammation drugs (NSAID), glucosamine supplementation, hyaluronic acid, arthroscopic debridement, and total joint replacement. Total joint replacement is commonly used in patients with severe OA who failed respond to pharmacological treatment. However, some patients received surgery had serious adverse events, including instability of the implants due to insufficient adhesion to the adjacent bony tissue or synovial inflammation. We tried to develop ideal nano-topographic oxidized silicon nanosponges by using with various chemicals to produce thickness difference in nanometers in order to study more about the cell-environment interactions in vitro like the alterations of cell adhesion, morphology, extracellular matrix secretions in the pathogenesis of osteoarthritis. Cytokines studies like growth factor, reactive oxygen species, reactive inflammatory materials (Like nitrous oxide and prostaglandin E2), extracellular matrix (ECM) degradation enzymes, and synthesis of collagen will also be observed and discussed. Extracellular and intracellular expression transforming growth factor beta (TGF-β) will be studied by reverse transcription-polymerase chain reaction (RT-PCR). The degradation of ECM will be observed by the bioactivity ratio of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinase by ELISA (Enzyme-linked immunosorbent assay). When rabbit synoviocytes were cultured on these nano-topographic structures, they demonstrate better cell adhesion rate, decreased expression of MMP-2,9 and PGE2, and increased expression of TGF-β when cultured in nano-topographic oxidized silicon nanosponges than in the planar oxidized silicon ones. These results show cell behavior, cytokine production can be influenced by physical characteristics from different nano-topographic structures. Our study demonstrates the possibility of manipulating cell behavior in these nano-topographic biomaterials.

Keywords: osteoarthritis, synoviocyte, oxidized silicon surfaces, reactive oxygen species

Procedia PDF Downloads 388

Authors: Tony R. Walker, N. Devin MacAskill, Andrew Thalhiemer

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Sydney Harbour, Nova Scotia has long been subject to effluent and atmospheric inputs of metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) from a large coking operation and steel plant that operated in Sydney for nearly a century until closure in 1988. Contaminated effluents from the industrial site resulted in the creation of the Sydney Tar Ponds, one of Canada’s largest contaminated sites. Since its closure, there have been several attempts to remediate this former industrial site and finally, in 2004, the governments of Canada and Nova Scotia committed to remediate the site to reduce potential ecological and human health risks to the environment. The Sydney Tar Ponds and Coke Ovens cleanup project has become the most prominent remediation project in Canada today. As an integral part of remediation of the site (i.e., which consisted of solidification/stabilization and associated capping of the Tar Ponds), an extensive multiple media environmental effects program was implemented to assess what effects remediation had on the surrounding environment, and, in particular, harbour sediments. Additionally, longer-term natural sediment recovery rates of select contaminants predicted for the harbour sediments were compared to current conditions. During remediation, potential contributions to sediment quality, in addition to remedial efforts, were evaluated which included a significant harbour dredging project, propeller wash from harbour traffic, storm events, adjacent loading/unloading of coal and municipal wastewater treatment discharges. Two sediment sampling methodologies, sediment grab and gravity corer, were also compared to evaluate the detection of subtle changes in sediment quality. Results indicated that overall spatial distribution pattern of historical contaminants remains unchanged, although at much lower concentrations than previously reported, due to natural recovery. Measurements of sediment indicator parameter concentrations confirmed that natural recovery rates of Sydney Harbour sediments were in broad agreement with predicted concentrations, in spite of ongoing remediation activities. Overall, most measured parameters in sediments showed little temporal variability even when using different sampling methodologies, during three years of remediation compared to baseline, except for the detection of significant increases in total PAH concentrations noted during one year of remediation monitoring. The data confirmed the effectiveness of mitigation measures implemented during construction relative to harbour sediment quality, despite other anthropogenic activities and the dynamic nature of the harbour.

Keywords: contaminated sediment, monitoring, recovery, remediation

Procedia PDF Downloads 236

Authors: Kim Kennedy, Daren Gibson, Stephanie Flukes, Chandra Diwakarla, Lisa Spalding, Leanne Pilkington, Andrew Redfern

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Introduction: Head and neck cancer and treatments are known for their profound effect on nutrition and tube feeding is a common requirement to maintain nutrition. Aim: We aimed to evaluate the frequency of tube feeding in Aboriginal and non-Aboriginal patients, and to examine the relapse and survival outcomes in patients who require enteral tube feeding. Methods: We performed a retrospective cohort analysis of 320 head and neck cancer patients from a single centre in Western Australia, identifying 80 Aboriginal patients and 240 non-Aboriginal patients matched on a 1:3 ratio by site, histology, rurality, and age. Data collected included patient demographics, tumour features, treatment details, and cancer and survival outcomes. Results: Aboriginal and non-Aboriginal patients required feeding tubes at similar rates (42.5% vs 46.2% respectively), however Aboriginal patients were far more likely to fail to return to oral nutrition, with 26.3% requiring long-term tube feeding versus only 15% of non-Aboriginal patients. In the overall study population, 27.5% required short-term tube feeding, 17.8% required long-term enteral tube nutrition, and 45.3% of patients did not have a feeding tube at any point. Relapse was more common in patients who required tube feeding, with relapses in 42.1% of the patients requiring long-term tube feeding, 31.8% in those requiring a short-term tube, versus 18.9% in the ‘no tube’ group. Survival outcomes for patients who required a long-term tube were also significantly poorer when compared to patients who only required a short-term tube, or not at all. Long-term tube-requiring patients were half as likely to survive (29.8%) compared to patients requiring a short-term tube (62.5%) or no tube at all (63.5%). Patients requiring a long-term tube were twice as likely to die with active disease (59.6%) as patients with no tube (28%), or a short term tube (33%). This may suggest an increased relapse risk in patients who require long-term feeding, due to consequences of malnutrition on cancer and treatment outcomes, although may simply reflect that patients with recurrent disease were more likely to have longer-term swallowing dysfunction due to recurrent disease and salvage treatments. Interestingly long-term tube patients were also more likely to die with no active disease (10.5%) (compared with short-term tube requiring patients (4.6%), or patients with no tube (8%)), which is likely reflective of the increased mortality associated with long-term aspiration and malnutrition issues. Conclusions: Requirement for tube feeding was associated with a higher rate of cancer relapse, and in particular, long-term tube feeding was associated with a higher likelihood of dying from head and neck cancer, but also a higher risk of dying from other causes without cancer relapse. This data reflects the complex effect of head and neck cancer and its treatments on swallowing and nutrition, and ultimately, the effects of malnutrition, swallowing dysfunction, and aspiration on overall cancer and survival outcomes. Tube feeding was seen at similar rates in Aboriginal and non-Aboriginal patient, however failure to return to oral intake with a requirement for a long-term feeding tube was seen far more commonly in the Aboriginal population.

Keywords: head and neck cancer, enteral tube feeding, malnutrition, survival, relapse, aboriginal patients

Procedia PDF Downloads 103

Authors: P. H. G. J. Pushpakumara, Andrew Dawson

Abstract:

Introduction: Deliberate self harm (DSH) is a major public health problem globally. Suicide rates of Sri Lanka are being among the highest national rates in the world, since 1950. Previous DSH is the most important independent predictor of repetition. The estimated 1 year non-fatal repeat self-harm rate was 16.3%. Asian countries had considerably lower rate, 10.0%. Objectives: To calculate incidence of deliberate self-poisoning (DSP) and suicides, repetition rate of DSP in Kurunegala District (KD). To determine the pattern of repeated DSP in KD. Methods: Study had two components. In the first component, demographic and event related details of, DSP admission in 46 hospitals and suicides in 28 police stations of KD were collected for 3 years from January 2011. Demographic details of cohort of DSP patients admitted to above hospitals in 2011 were linked with hospital admissions and police records of next two years period from the index admission. Records were screened for links with high sensitivity using the computer then did manual matching which would have been much more specific. In the second component, randomly selected DSP patients (n=438), who admitted to main referral centre which receives 60% of DSP cases of the district, were interviewed to assess life-time repetition. Results: There were 16,993 DSP admissions and 1078 suicides for the three year period. Suicide incidences in KD were, 21.6, 20.7 and 24.3 per 100,000 population in 2011, 2012 and 2013. Average male to female ratio for suicide incidences was 5.5. DSP incidences were 205.4, 248.3 and 202.5 per 100,000 population. Male incidences were slightly greater than the female incidences, male: female ratio was 1.1:1. Highest age standardized male and female incidence was reported in 20-24 years age group, 769.6/100,000, and 15-19 years age group 1304.0/100,000. Male to female ratio of the incidence increased with the age. There were 318 (179 male and 139 female) patients attempted DSH within two years. Female repetitive patients were ounger compared to the males, p < 0.0001, median age: males 28 and females 19 years. 290 (91.2%) had only one repetitive attempt, 24 (7.5%) had two, 3 (0.9%) had three and one (0.3%) had four in that period. One year repetition rate was 5.6 and two year repetition rate was 7.9%. Average intervals between indexed events and first repetitive DSP events were 246.8 (SD:223.4) and 238.5 (SD:207.0) days among males and females. One fifth of first repetitive events occurred within first two weeks in both males and females. Around 50% of males and females had the second event within 28 weeks. Within the first year of the indexed event, around 70% had the second event. First repetitive event was fatal for 28 (8.8%) individuals. Ages of those who died, mean 49.7 years (SD:15.3), were significantly higher compared to those who had non-fatal outcome, p<0.0001. 9.5% had life time history of DSH attempts. Conclusions: Both, DSP and suicide incidences were very high in KD. However, repetition rates were lesser compared regional values. Prevention of repetition alone may not produce significant impact on prevention of DSH.

Keywords: deliberate self-harm, incidence, repetition, Sri Lanka, suicide

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