Search results for: adversarial sample

Authors: Neeti Nayak, Khalid Duri

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Despite the many advances made in transportation planning, the number of injuries and fatalities in the United States which involve motorized vehicles near intersections remain largely unchanged year over year. Data from the National Highway Traffic Safety Administration for 2018 indicates accidents involving motorized vehicles at traffic intersections accounted for 8,245 deaths and 914,811 injuries. Furthermore, collisions involving pedal cyclists killed 861 people (38% at intersections) and injured 46,295 (68% at intersections), while accidents involving pedestrians claimed 6,247 lives (25% at intersections) and injured 71,887 (56% at intersections)- the highest tallies registered in nearly 20 years. Some of the causes attributed to the rising number of accidents relate to increasing populations and the associated changes in land and traffic usage patterns, insufficient visibility conditions, and inadequate applications of traffic controls. Intersections that were initially designed with a particular land use pattern in mind may be rendered obsolete by subsequent developments. Many accidents involving pedestrians are accounted for by locations which should have been designed for safe crosswalks. Conventional solutions for evaluating intersection safety often require costly deployment of engineering surveys and analysis, which limit the capacity of resource-constrained administrations to satisfy their community’s needs for safe roadways adequately, effectively relegating mitigation efforts for high-risk areas to post-incident responses. This paper demonstrates how geospatial technology can identify high-risk locations and evaluate the viability of specific intersection management techniques. GIS is used to simulate relevant real-world conditions- the presence of traffic controls, zoning records, locations of interest for human activity, design speed of roadways, topographic details and immovable structures. The proposed methodology provides a low-cost mechanism for empowering urban planners to reduce the risks of accidents using 2-dimensional data representing multi-modal street networks, parcels, crosswalks and demographic information alongside 3-dimensional models of buildings, elevation, slope and aspect surfaces to evaluate visibility and lighting conditions and estimate probabilities for jaywalking and risks posed by blind or uncontrolled intersections. The proposed tools were developed using sample areas of Southern California, but the model will scale to other cities which conform to similar transportation standards given the availability of relevant GIS data.

Keywords: crosswalks, cyclist safety, geotechnology, GIS, intersection safety, pedestrian safety, roadway safety, transportation planning, urban design

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Authors: E. Akdur Öztürk, F. İrvasa Bilgiç, A. Ludovisi , O. Gülbahar, D. Dirim Erdoğan, M. Korkmaz, M. Á. Gómez Morales

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Anisakidosis is a zoonotic human fish-borne parasitic disease caused by accidental ingestion of anisakid third-stage larvae (L3) of members of the Anisakidae family present in infected marine fish or cephalopods. Infection with anisakid larvae can lead to gastric, intestinal, extra-gastrointestinal and gastroallergic forms of the disease. Anisakid parasites have been reported in almost all seas, particularly in the Mediterranean Sea. There is a remarkably high level of risk exposure to these zoonotic parasites as they are present in economically and ecologically important fish of Europe. Anisakid L3 larvae have been also detected in several fish species from the Aegean Sea. Turkey is a peninsular country surrounded by Black, Aegean and the Mediterranean Sea. In this country, fishing habit and fishery product consumption are highly common. In recent years, there was also an increase in the consumption of raw fish due to the increasing interest in the cuisine of the Far East countries. In different regions of Turkey, A. simplex (inMerluccius Merluccius Scomber japonicus, Trachurus mediterraneus, Sardina pilchardus, Engraulis encrasicolus, etc.), Anisakis spp., Contraceucum spp., Pseudoterronova spp. and, C. aduncum were identified as well. Although it is accepted both the presence of anisakid parasites in fish and fishery products in Turkey and the presence of Turkish people with allergic manifestations after fish consumption, there are no reports of human anisakiasis in this country. Given the high prevalence of anisakid parasites in the country, the absence of reports is likely not due to the absence of clinical cases rather to the unavailability of diagnostic tools and the low awareness of the presence of this infection. The aim of the study was to set up an IgE-Western Blot (WB) based test to detect the anisakidosis sensitization among Turkish people with a history of allergic manifestation related to fish consumption. To this end, crude worm antigens (CWA) and allergen enriched fraction (50-66% ) were prepared from L3 of A. simplex (s.l.) collected from Lepidopus caudatus fished in the Mediterranean Sea. These proteins were electrophoretically separated and transferred into the nitrocellulose membranes. By WB, specific proteins recognized by positive control serum samples from sensitized patients were visualized on nitrocellulose membranes by a colorimetric reaction. The CWA and 50–66% fraction showed specific bands, mainly due to Ani s 1 (20-22 kD) and Ani s 4 (9-10 kD). So far, a total of 7 serum samples from people with allergic manifestation and positive skin prick test (SPT) after fish consumption, have been tested and all of them resulted negative by WB, indicating the lack of sensitization to anisakids. This preliminary study allowed to set up a specific test and evidence the lack of correlation between both tests, SPT and WB. However, the sample size should be increased to estimate the anisakidosis burden in Turkish people.

Keywords: anisakidosis, fish parasite, serodiagnosis, Turkey

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Authors: Henry Kiptum Yatich, Ronald Chepkilot, Aquilars Mutuku Kalio

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Studies on energy management have focused on environmental conservation, reduction in production and operation expenses. However, transferring gains of energy management practices to competitive advantage is importance to manufacturers in Kenya. Success in managing competitive advantage arises out of a firm’s ability in identifying and implementing actions that can give the company an edge over its rivals. Manufacturing firms in Kenya are the highest consumers of both electricity and petroleum products. In this regard, the study posits that transfer of the gains of energy management practices to competitive advantage is imperative. The study was carried in Nairobi and its environs, which hosts the largest number of manufacturers. The study objectives were; to determine the level of implementing energy management regulations on sustaining competitive advantage, to determine the level of implementing company energy management policy on competitive advantage, to examine the level of implementing energy efficient technology on sustaining competitive advantage, and to assess the percentage energy expenditure on sustaining competitive advantage among manufacturing firms. The study adopted a survey research design, with a study population of 145,987. A sample of 384 respondents was selected randomly from 21 proportionately selected firms. Structured questionnaires were used to collect data. Data analysis was done using descriptive statistics (mean and standard deviations) and inferential statistics (correlation, regression, and T-test). Data is presented using tables and diagrams. The study found that Energy Management Regulations, Company Energy Management Policies, and Energy Expenses are significant predictors of Competitive Advantage (CA). However, Energy Efficient Technology as a component of Energy Management Practices did not have a significant relationship with Competitive Advantage. The study revealed that the level of awareness in the sector stood at 49.3%. Energy Expenses in the sector stood at an average of 10.53% of the firm’s total revenue. The study showed that gains from energy efficiency practices can be transferred to competitive strategies so as to improve firm competitiveness. The study recommends that manufacturing firms should consider energy management practices as part of its strategic agenda in assessing and reviewing their energy management practices as possible strategies for sustaining competitiveness. The government agencies such as Energy Regulatory Commission, the Ministry of Energy and Petroleum, and Kenya Association of Manufacturers should enforce the energy management regulations 2012, and with enhanced stakeholder involvement and sensitization so as promote sustenance of firm competitiveness. Government support in providing incentives and rebates for acquisition of energy efficient technologies should be pursued. From the study limitation, future experimental and longitudinal studies need to be carried out. It should be noted that energy management practices yield enormous benefits to all stakeholders and that the practice should not be considered a competitive tool but rather as a universal practice.

Keywords: energy, efficiency, management, guidelines, policy, technology, competitive advantage

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Authors: Pamela Ventola, Laurel Bales, Sara Florczyk

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Background: Fully remote or hybrid administration of clinical outcome measures in rare neurodevelopmental disorders trials is increasing due to the ongoing pandemic and recognition that remote assessments reduce the burden on families. Many assessments in rare neurodevelopmental disorders trials are complex; however, remote/hybrid trials readily allow for the use of centralized raters to administer and score the scales. The use of centralized raters has many benefits, including reducing site burden; however, a specific impact on data quality has not yet been determined. Purpose: The current study has two aims: a) evaluate differences in data quality between administration of a standardized clinical interview completed by centralized raters compared to those completed by site raters and b) evaluate improvement in accuracy of scoring standardized developmental assessments when scored centrally compared to when scored by site raters. Methods: For aim 1, the Vineland-3, a widely used measure of adaptive functioning, was administered by site raters (n= 52) participating in one of four rare disease trials. The measure was also administered as part of two additional trials that utilized central raters (n=7). Each rater completed a comprehensive training program on the assessment. Following completion of the training, each clinician completed a Vineland-3 with a mock caregiver. Administrations were recorded and reviewed by a neuropsychologist for administration and scoring accuracy. Raters were able to certify for the trials after demonstrating an accurate administration of the scale. For site raters, 25% of each rater’s in-study administrations were reviewed by a neuropsychologist for accuracy of administration and scoring. For central raters, the first two administrations and every 10th administration were reviewed. Aim 2 evaluated the added benefit of centralized scoring on the accuracy of scoring of the Bayley-3, a comprehensive developmental assessment widely used in rare neurodevelopmental disorders trials. Bayley-3 administrations across four rare disease trials were centrally scored. For all administrations, the site rater who administered the Bayley-3 scored the scale, and a centralized rater reviewed the video recordings of the administrations and also scored the scales to confirm accuracy. Results: For aim 1, site raters completed 138 Vineland-3 administrations. Of the138 administrations, 53 administrations were reviewed by a neuropsychologist. Four of the administrations had errors that compromised the validity of the assessment. The central raters completed 180 Vineland-3 administrations, 38 administrations were reviewed, and none had significant errors. For aim 2, 68 administrations of the Bayley-3 were reviewed and scored by both a site rater and a centralized rater. Of these administrations, 25 had errors in scoring that were corrected by the central rater. Conclusion: In rare neurodevelopmental disorders trials, sample sizes are often small, so data quality is critical. The use of central raters inherently decreases site burden, but it also decreases rater variance, as illustrated by the small team of central raters (n=7) needed to conduct all of the assessments (n=180) in these trials compared to the number of site raters (n=53) required for even fewer assessments (n=138). In addition, the use of central raters dramatically improves the quality of scoring the assessments.

Keywords: neurodevelopmental disorders, clinical trials, rare disease, central raters, remote trials, decentralized trials

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Authors: K. Verma, v. S. Moholkar

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In developed countries, water pollution caused by industrial discharge has emerged as a significant environmental concern over the past decades. However, despite ongoing efforts, a fully effective and sustainable remediation strategy has yet to be identified. This paper describes how enzymatic and sonochemical treatments have demonstrated great promise in degrading bio-refractory pollutants. Mainly, a compelling area of interest lies in the combined technique of sono-enzymatic treatment, which has exhibited a synergistic enhancement effect surpassing that of the individual techniques. This study employed the covalent attachment method to immobilize Laccase from Trametes versicolor onto amino-functionalized magnetic Fe₃O₄ nanoparticles. To comprehensively characterize the synthesized free nanoparticles and the laccase-immobilized nanoparticles, various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and surface area through Brunauer-Emmett-Teller (BET) were employed. The size of immobilized Fe₃O₄@Laccase was found to be 60 nm, and the maximum loading of laccase was found to be 24 mg/g of nanoparticle. An investigation was conducted to study the effect of various process parameters, such as immobilized Fe₃O₄ Laccase dose, temperature, and pH, on the % Chemical oxygen demand (COD) removal as a response. The statistical design pinpointed the optimum conditions (immobilized Fe₃O₄ Laccase dose = 1.46 g/L, pH = 4.5, and temperature = 66 oC), resulting in a remarkable 65.58% COD removal within 60 minutes. An even more significant improvement (90.31% COD removal) was achieved with ultrasound-assisted enzymatic reaction utilizing a 10% duty cycle. The investigation of various kinetic models for free and immobilized laccase, such as the Haldane, Yano, and Koga, and Michaelis-Menten, showed that ultrasound application impacted the kinetic parameters Vmax and Km. Specifically, Vmax values for free and immobilized laccase were found to be 0.021 mg/L min and 0.045 mg/L min, respectively, while Km values were 147.2 mg/L for free laccase and 136.46 mg/L for immobilized laccase. The lower Km and higher Vmax for immobilized laccase indicate its enhanced affinity towards the substrate, likely due to ultrasound-induced alterations in the enzyme's confirmation and increased exposure of active sites, leading to more efficient degradation. Furthermore, the toxicity and Liquid chromatography-mass spectrometry (LC-MS) analysis revealed that after the treatment process, the wastewater exhibited 70% less toxicity than before treatment, with over 25 compounds degrading by more than 75%. At last, the prepared immobilized laccase had excellent recyclability retaining 70% activity up to 6 consecutive cycles. A straightforward manufacturing strategy and outstanding performance make the recyclable magnetic immobilized Laccase (Fe₃O₄ Laccase) an up-and-coming option for various environmental applications, particularly in water pollution control and treatment.

Keywords: kinetic, laccase enzyme, sonoenzymatic, ultrasound irradiation

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Authors: Thais O. de Paula, Marjorie R. A. Sarmiento, Francis M. Borges, Alessandra B. Ferreira-Machado, Juliana A. Resende, Dioneia E. Cesar, Vania L. Silva, Claudio G. Diniz

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Obesity is currently a worldwide public health threat, being considered a pandemic multifactorial disease related to the human gut microbiota (GM). Add to that GM is considered an important reservoir of antimicrobial resistance genes (ARG) and little is known on GM and ARG in obesity, considering the altered physiology and xenobiotics intake. As regional and social behavior may play important roles in GM modulation, and most of the studies are based on small sample size and various methodological approaches resulting in difficulties for data comparisons, this study was focused on the investigation of GM bacterial diversity in obese (OB), overweight (OW) and eutrophic individuals (ET) considering their nutritional, clinical and social characteristics; and comparative screening of AGR related to their physiology and xenobiotics intake. Microbial community was accessed by FISH considering phyla as a taxonomic level, and PCR-DGGE followed by dendrograms evaluation (UPGMA method) from fecal metagenome of 72 volunteers classified according to their body mass index (BMI). Nutritional, clinical, social parameters and xenobiotics intake were recorded for correlation analysis. The fecal metagenome was also used as template for PCR targeting 59 different ARG. Overall, 62% of OB were hypertensive, and 12% or 4% were, regarding the OW and ET individuals. Most of the OB were rated as low income (80%). Lower relative bacterial densities were observed in the OB compared to ET for almost all studied taxa (p < 0.05) with Firmicutes/Bacteroidetes ratio increased in the OB group. OW individuals showed a bacterial density representative of GM more likely to the OB. All the participants were clustered in 3 different groups based on the PCR-DGGE fingerprint patterns (C1, C2, C3), being OB mostly grouped in C1 (83.3%) and ET mostly grouped in C3 (50%). The cluster C2 showed to be transitional. Among 27 ARG detected, a cluster of 17 was observed in all groups suggesting a common core. In general, ARG were observed mostly within OB individuals followed by OW and ET. The ratio between ARG and bacterial groups may suggest that AGR were more related to enterobacteria. Positive correlations were observed between ARG and BMI, calories and xenobiotics intake (especially use of sweeteners). As with nutritional and clinical characteristics, our data may suggest that GM of OW individuals behave in a heterogeneous pattern, occasionally more likely to the OB or to the ET. Regardless the regional and social behaviors of our population, the methodological approaches in this study were complementary and confirmatory. The imbalance of GM over the health-disease interface in obesity is a matter of fact, but its influence in host's physiology is still to be clearly elucidated to help understanding the multifactorial etiology of obesity. Although the results are in agreement with observations that GM is altered in obesity, the altered physiology in OB individuals seems to be also associated to the increased xenobiotics intake and may interfere with GM towards antimicrobial resistance, as observed by the fecal metagenome and ARG screening. Support: FAPEMIG, CNPQ, CAPES, PPGCBIO/UFJF.

Keywords: antimicrobial resistance, bacterial diversity, gut microbiota, obesity

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Authors: Marcin Zielinski, Marcin Debowski, Paulina Rusanowska, Magda Dudek

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As a result of sonification, the destruction of complex biomass structures results in an increase in the biogas yield from the conditioned material. First, the amount of organic matter released into the solution due to disintegration was determined. This parameter was determined by changes in the carbon content in liquid phase of the conditioned substrate. The amount of carbon in the liquid phase increased with the prolongation of the sonication time to 16 min. Further increase in the duration of sonication did not cause a statistically significant increase in the amount of organic carbon in the liquid phase. The disintegrated material was then used for respirometric measurements for determination of the impact of the conditioning process used on methane fermentation effectiveness. The relationship between the amount of energy introduced into the lignocellulosic substrate and the amount of biogas produced has been demonstrated. Statistically significant increase in the amount of biogas was observed until sonication of 16 min. Further increase in energy in the conditioning process did not significantly increase the production of biogas from the treated substrate. The biogas production from the conditioned substrate was 17% higher than from the reference biomass at that time. The ultrasonic disintegration method did not significantly affect the observed biogas composition. In all series, the methane content in the produced biogas from the conditioned substrate was similar to that obtained with the raw substrate sample (51.1%). Another method of substrate conditioning was hydrothermal depolymerization. This method consists in application of increased temperature and pressure to substrate. These phenomena destroy the structure of the processed material, the release of organic compounds to the solution, which should lead to increase the amount of produced biogas from such treated biomass. The hydrothermal depolymerization was conducted using an innovative microwave heating method. Control measurements were performed using conventional heating. The obtained results indicate the relationship between depolymerization temperature and the amount of biogas. Statistically significant value of the biogas production coefficients increased as the depolymerization temperature increased to 150°C. Further raising the depolymerization temperature to 180°C did not significantly increase the amount of produced biogas in the respirometric tests. As a result of the hydrothermal depolymerization obtained using microwave at 150°C for 20 min, the rate of biogas production from the Sida silage was 780 L/kg VS, which accounted for nearly 50% increase compared to 370 L/kg VS obtained from the same silage but not depolymerised. The study showed that by microwave heating it is possible to effectively depolymerized substrate. Significant differences occurred especially in the temperature range of 130-150ºC. The pre-treatment of Sida hermaphrodita silage (biogas substrate) did not significantly affect the quality of the biogas produced. The methane concentration was about 51.5% on average. The study was carried out in the framework of the project under program BIOSTRATEG funded by the National Centre for Research and Development No. 1/270745/2/NCBR/2015 'Dietary, power, and economic potential of Sida hermaphrodita cultivation on fallow land'.

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

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Authors: Afsheen Aman, Zainab Bibi, Shah Ali Ul Qader

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Introduction: Xylan is a heteropolysaccharide composed of xylose monomers linked together through 1,4 linkages within a complex xylan network. Owing to wide applications of xylan hydrolytic products (xylose, xylobiose and xylooligosaccharide) the researchers are focusing towards the development of various strategies for efficient xylan degradation. One of the most important strategies focused is the use of heat tolerant biocatalysts which acts as strong and specific cleaving agents. Therefore, the exploration of microbial pool from extremely diversified ecosystem is considerably vital. Microbial populations from extreme habitats are keenly explored for the isolation of thermophilic entities. These thermozymes usually demonstrate fast hydrolytic rate, can produce high yields of product and are less prone to microbial contamination. Another possibility of degrading xylan continuously is the use of immobilization technique. The current work is an effort to merge both the positive aspects of thermozyme and immobilization technique. Methodology: Geobacillus stearothermophilus was isolated from soil sample collected near the blast furnace site. This thermophile is capable of producing thermostable endo-β-1,4-xylanase which cleaves xylan effectively. In the current study, this thermozyme was immobilized within a synthetic and a non-synthetic matrice for continuous production of metabolites using entrapment technique. The kinetic parameters of the free and immobilized enzyme were studied. For this purpose calcium alginate and polyacrylamide beads were prepared. Results: For the synthesis of immobilized beads, sodium alginate (40.0 gL-1) and calcium chloride (0.4 M) was used amalgamated. The temperature (50°C) and pH (7.0) optima of immobilized enzyme remained same for xylan hydrolysis however, the enzyme-substrate catalytic reaction time raised from 5.0 to 30.0 minutes as compared to free counterpart. Diffusion limit of high molecular weight xylan (corncob) caused a decline in Vmax of immobilized enzyme from 4773 to 203.7 U min-1 whereas, Km value increased from 0.5074 to 0.5722 mg ml-1 with reference to free enzyme. Immobilized endo-β-1,4-xylanase showed its stability at high temperatures as compared to free enzyme. It retained 18% and 9% residual activity at 70°C and 80°C, respectively whereas; free enzyme completely lost its activity at both temperatures. The Immobilized thermozyme displayed sufficient recycling efficiency and can be reused up to five reaction cycles, indicating that this enzyme can be a plausible candidate in paper processing industry. Conclusion: This thermozyme showed better immobilization yield and operational stability with the purpose of hydrolyzing the high molecular weight xylan. However, the enzyme immobilization properties can be improved further by immobilizing it on different supports for industrial purpose.

Keywords: immobilization, reusability, thermozymes, xylanase

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Authors: Kristina Colovic, Mari Janikian, Nikolaos Takis, Fotini-Sonia Apergi

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A considerable number of Afghan asylum seekers in Greece are still waiting for answers about their future and status for personal, social and societal advancement. Most have been trapped in a stalemate of continuously postponed or temporarily progressed levels of integration into the EU/Greek process of asylum. Limited quantitative research exists investigating the psychological effects of long-term displacement among Afghans refugees in Greece. The purpose of this study is to investigate factors that are associated with and predict psychological distress symptoms among this population. Data from a sample of native Afghan nationals (N > 70) living in Greece for approximately the last ten years will be collected from May to July 2016. Criteria for participation include the following: being 18 years of age or older, and emigration from Afghanistan to Greece from 2003 onwards (i.e., long-term refugees or part of the 'old system of asylum'). Snowball sampling will be used to recruit participants, as this is considered the most effective option when attempting to study refugee populations. Participants will complete self-report questionnaires, consisting of the Afghan Symptom Checklist (ASCL), a culturally validated measure of psychological distress, the World Health Organization Quality of Life scale (WHOQOL-BREF), an adapted version of the Comprehensive Trauma Inventory-104 (CTI-104), and a modified Psychological Acculturation Scale. All instruments will be translated in Greek, through the use of forward- and back-translations by bilingual speakers of English and Greek, following WHO guidelines. A pilot study with 5 Afghan participants will take place to check for discrepancies in understanding and for further adapting the instruments as needed. Demographic data, including age, gender, year of arrival to Greece and current asylum status will be explored. Three different types of analyses (descriptive statistics, bivariate correlations, and multivariate linear regression) will be used in this study. Descriptive findings for respondent demographics, psychological distress symptoms, traumatic life events and quality of life will be reported. Zero-order correlations will assess the interrelationships among demographic, traumatic life events, psychological distress, and quality of life variables. Lastly, a multivariate linear regression model will be estimated. The findings from the study will contribute to understanding the determinants of acculturation, distress and trauma on daily functioning for Afghans in Greece. The main implications of the current study will be to advocate for capacity building and empower communities through effective program evaluation and design for mental health services for all refugee populations in Greece.

Keywords: Afghan refugees, evaluation, Greece, mental health, quality of life

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Authors: Florence Roselle Adalin, Misha Louise Delariarte, Fabbette Laire Lagas, Sarah Emanuelle Mejia, Lika Mizukoshi, Irish Paullen Palomeno, Gibrianne Alistaire Ramos, Danica Pauline Ramos, Josefina Tuazon, Jo Leah Flores

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Pain, often a missed and undertreated symptom, affects the quality of life of individuals. Nurses are key players in providing effective pain management to decrease morbidity and mortality of patients in pain. Nurses’ knowledge and attitude on pain greatly affect their ability on assessment and management. The Pain Society of the Philippines recognized the inadequacy and inaccessibility of data on the knowledge, skills, and attitude of nurses on pain management in the country. This study may be the first of its kind in the county, giving it the potential to contribute greatly to nursing education and practice through providing valuable baseline data. Objectives: This study aims to describe the level of knowledge and attitude, and current practices of nurses on pain assessment and management; and determine the relationship of nurses’ knowledge and attitude with years of experience, training on pain management and clinical area of practice. Methodology: A survey research design was employed. Four hospitals were selected through purposive sampling. A total of 235 Medical-Surgical Unit and Intensive Care Unit (ICU) nurses participated in the study. The tool used is a combination of demographic survey, Nurses’ Knowledge and Attitude Survey Regarding Pain (NKASRP), Acute Pain Evidence Based Practice Questionnaire (APEBPQ) with self-report questions on non-pharmacologic pain management. The data obtained was analysed using descriptive statistics, two sample T-tests for clinical areas and training; and Pearson product correlation to identify relationship of level of knowledge and attitude with years of experience. Results and Analysis: The mean knowledge and attitude score of the nurses was 47.14%. Majority answered ‘most of the time’ or ‘all the time’ on 84.12% of practice items on pain assessment, implementation of non-pharmacologic interventions, evaluation and documentation. Three of 19 practice items describing morphine and opioid administration in special populations were only done ‘a little of the time’. Most utilized non-pharmacologic interventions were deep breathing exercises (79.66%), massage therapy (27.54%), and ice therapy (26.69%). There was no significant relationship between knowledge scores and years of clinical experience (p = 0.05, r= -0.09). Moreover, there was not enough evidence to show difference in nurses’ knowledge and attitude scores in relation to presence of training (p = 0.41) or areas (Medical-Surgical or ICU) of clinical practice (p = 0.53). Conclusion and Recommendations: Findings of the study showed that the level of knowledge and attitude of nurses on pain assessment and management is suboptimal; and no relationship between nurses’ knowledge and attitude and years of experience. It is recommended that further studies look into the nursing curriculum on pain education, culture-specific pain management protocols and evidence-based practices in the country.

Keywords: knowledge and attitude, nurses, pain management, practices on pain management

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Authors: Jayden R. Hunter, Alexander J. MacQuarrie, Samantha C. Sheridan, Richard High, Carolyn Waite

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Workplace exercise programs have been recommended to improve the musculoskeletal fitness of paramedics with the aim of reducing injury rates, and while they have shown efficacy in other occupations, they have not been delivered and evaluated in Australian paramedics to our best knowledge. This study investigated the effectiveness of a 6-month workplace exercise program (MedicFit; MF) to improve paramedic fitness with or without health coach (HC) support. A group of regional Australian paramedics (n=76; 43 male; mean ± SD 36.5 ± 9.1 years; BMI 28.0 ± 5.4 kg/m²) were randomised at the station level to either exercise with remote health coach support (MFHC; n=30), exercise without health coach support (MF; n=23), or no-exercise control (CON; n=23) groups. MFHC and MF participants received a 6-month, low-moderate intensity resistance and flexibility exercise program to be performed ƒ on station without direct supervision. Available exercise equipment included dumbbells, resistance bands, Swiss balls, medicine balls, kettlebells, BOSU balls, yoga mats, and foam rollers. MFHC and MF participants were also provided with a comprehensive exercise manual including sample exercise sessions aimed at improving musculoskeletal strength and flexibility which included exercise prescription (i.e. sets, reps, duration, load). Changes to upper-body (push-ups), lower-body (wall squat) and core (plank hold) strength and flexibility (back scratch and sit-reach tests) after the 6-month intervention were analysed using repeated measures ANOVA to compare changes between groups and over time. Upper-body (+20.6%; p < 0.01; partial eta squared = 0.34 [large effect]) and lower-body (+40.8%; p < 0.05; partial eta squared = 0.08 (moderate effect)) strength increased significantly with no interaction or group effects. Changes to core strength (+1.4%; p=0.17) and both upper-body (+19.5%; p=0.56) and lower-body (+3.3%; p=0.15) flexibility were non-significant with no interaction or group effects observed. While upper- and lower-body strength improved over the course of the intervention, providing a 6-month workplace exercise program with or without health coach support did not confer any greater strength or flexibility benefits than exercise testing alone (CON). Although exercise adherence was not measured, it is possible that participants require additional methods of support such as face-to-face exercise instruction and guidance and individually-tailored exercise programs to achieve adequate participation and improvements in musculoskeletal fitness. This presents challenges for more remote paramedic stations without regular face-to-face access to suitably qualified exercise professionals, and future research should investigate the effectiveness of other forms of exercise delivery and guidance for these paramedic officers such as remotely-facilitated digital exercise prescription and monitoring.

Keywords: workplace exercise, paramedic health, strength training, flexibility training

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Authors: Maria C. Almario, Pam Remer, Jeff Resse, Kathy Moran, Linda Theander Adam

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The identification of victims of human trafficking and consequential service provision is characterized by a significant disconnection between the estimated prevalence of this issue and the number of cases identified. This poses as tremendous problem for human rights advocates as it prevents data collection, information sharing, allocation of resources and opportunities for international dialogues. The current paper introduces the Inclusive Human Trafficking Checklist (IHTC) as a measurement methodology with theoretical underpinnings derived from dialectic theory. The presence of human trafficking in a person’s life is conceptualized as a dynamic and dialectic interaction between vulnerability and exploitation. The current papers explores the operationalization of exploitation and vulnerability, evaluates the metric qualities of the instrument, evaluates whether there are differences in assessment based on the participant’s profession, level of knowledge, and training, and assesses if users of the instrument perceive it as useful. A total of 201 participants were asked to rate three vignettes predetermined by experts to qualify as a either human trafficking case or not. The participants were placed in three conditions: business as usual, utilization of the IHTC with and without training. The results revealed a statistically significant level of agreement between the expert’s diagnostic and the application of the IHTC with an improvement of 40% on identification when compared with the business as usual condition While there was an improvement in identification in the group with training, the difference was found to have a small effect size. Participants who utilized the IHTC showed an increased ability to identify elements of identity-based vulnerabilities as well as elements of fraud, which according to the results, are distinctive variables in cases of human trafficking. In terms of the perceived utility, the results revealed higher mean scores for the groups utilizing the IHTC when compared to the business as usual condition. These findings suggest that the IHTC improves appropriate identification of cases and that it is perceived as a useful instrument. The application of the IHTC as a multidisciplinary instrumentation that can be utilized in legal and human services settings is discussed as a pivotal piece of helping victims restore their sense of dignity, and advocate for legal, physical and psychological reparations. It is noteworthy that this study was conducted with a sample in the United States and later re-tested in Colombia. The implications of the instrument for treatment conceptualization and intervention in human trafficking cases are discussed as opportunities for enhancement of victim well-being, restoration engagement and activism. With the idea that what is personal is also political, we believe that the careful observation and data collection in specific cases can inform new areas of human rights activism.

Keywords: exploitation, human trafficking, measurement, vulnerability, screening

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Authors: Yuki Matsumoto, Yuma Ishimoto

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Cognitive Behavior Therapy (CBT) with children has shown effective application to various problems such as anxiety and depression. Although there are barriers to access to mental health services including lack of professional services in communities and parental concerns about stigma, school has a significant role to address children’s health problems. Schools are regarded as a suitable arena for prevention and early intervention of mental health problems. In this line, CBT can be adaptable to school education and useful to enhance students’ social and emotional skills. However, Japanese school curriculum is rigorous so as to limit available time for implementation of CBT in schools. This paper describes Brief Cognitive Behavior Therapy (BCBT) with children in a Japanese school setting. The program has been developed in order to facilitate acceptability of CBT in schools and aimed to enhance students’ skills to manage anxiety and difficult behaviors. The present research used a single arm design in which 30 students aged 9-10 years old participated. The authors provided teachers a CBT training workshop (two hours) at two primary schools in Tokyo metropolitan area and recruited participants in the research. A homeroom teacher voluntarily delivered a 6-session BCBT program (15 minutes each) in classroom periods which is called as Kaerinokai, a meeting before leaving school. Students completed a questionnaire sheet at pre- and post-periods under the supervision of the teacher. The sheet included the Spence Child Anxiety Scale (SCAS), the Depression Self-Rating Scale for Children (DSRS), and the Strengths and Difficulties Questionnaire (SDQ). The teacher was asked for feedback after the completion. Significant positive changes were found in the total and five of six sub-scales of the SCAS and the total difficulty scale of the SDQ. However, no significant changes were seen in Physical Injury Fear sub-scale of the SCAS, in the DSRS or the Prosocial sub-scale of the SDQ. The effect sizes are mostly between small and medium. The teacher commented that the program was easy to use and found positive changes in classroom activities and personal relationships. This preliminary research showed the feasibility of the BCBT in a school setting. The results suggest that the BCBT offers effective treatment for reduction in anxiety and in difficult behaviors. There is a good prospect of the BCBT suggesting that BCBT may be easier to be delivered than CBT by Japanese teachers to promote child mental health. The study has limitations including no control group, small sample size, or a short teacher training. Future research should address these limitations.

Keywords: brief cognitive behavior therapy, cognitive behavior therapy, mental health services in schools, teacher training workshop

Procedia PDF Downloads 333

Authors: A. F. Jaber, E. Dean, M. Liu, J. He, D. Sabata, J. Radel

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Background: Stroke is a serious health care concern and a major cause of disability in the United States. This condition impacts the individual’s functional ability to perform daily activities. Predicting functional performance of people with stroke assists health care professionals in optimizing the delivery of health services to the affected individuals. The purpose of this study was to identify significant predictors of Motor FIM and of Cognitive FIM subscores among individuals with stroke after discharge from inpatient rehabilitation (typically 4-6 weeks after stroke onset). A second purpose is to explore the relation among personal characteristics, health status, and functional performance of daily activities within 2 weeks of stroke onset. Methods: This study used a retrospective chart review to conduct a secondary analysis of data obtained from the Healthcare Enterprise Repository for Ontological Narration (HERON) database. The HERON database integrates de-identified clinical data from seven different regional sources including hospital electronic medical record systems of the University of Kansas Health System. The initial HERON data extract encompassed 1192 records and the final sample consisted of 207 participants who were mostly white (74%) males (55%) with a diagnosis of ischemic stroke (77%). The outcome measures collected from HERON included performance scores on the National Institute of Health Stroke Scale (NIHSS), the Glasgow Coma Scale (GCS), and the Functional Independence Measure (FIM). The data analysis plan included descriptive statistics, Pearson correlation analysis, and Stepwise regression analysis. Results: significant predictors of discharge Motor FIM subscores included age, baseline Motor FIM subscores, discharge NIHSS scores, and comorbid electrolyte disorder (R2 = 0.57, p <0.026). Significant predictors of discharge Cognitive FIM subscores were age, baseline cognitive FIM subscores, client cooperative behavior, comorbid obesity, and the total number of comorbidities (R2 = 0.67, p <0.020). Functional performance on admission was significantly associated with age (p < 0.01), stroke severity (p < 0.01), and length of hospital stay (p < 0.05). Conclusions: our findings show that younger age, good motor and cognitive abilities on admission, mild stroke severity, fewer comorbidities, and positive client attitude all predict favorable functional outcomes after inpatient stroke rehabilitation. This study provides health care professionals with evidence to evaluate predictors of favorable functional outcomes early at stroke rehabilitation, to tailor individualized interventions based on their client’s anticipated prognosis, and to educate clients about the benefits of making lifestyle changes to improve their anticipated rate of functional recovery.

Keywords: functional performance, predictors, stroke, recovery

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Authors: M. Lehtihet, S. Rosado, C. Pradère, J. Leng

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Poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT: PSS), is a polymer mixture well-known for its semiconducting properties and is widely used in the coating industry for its visible transparency and high electronic conductivity (up to 4600 S/cm) as a transparent non-metallic electrode and in organic light-emitting diodes (OLED). It also possesses strong absorption properties in the Near Infra-Red (NIR) range (λ ranging between 900 nm to 2.5 µm). In the present work, we take advantage of this absorption to explore its potential use as a transparent light-to-heat converter. PEDOT: PSS aqueous dispersions are deposited onto a glass substrate using a blade-coating technique in order to produce uniform coatings with controlled thicknesses ranging in ≈ 400 nm to 2 µm. Blade-coating technique allows us good control of the deposit thickness and uniformity by the tuning of several experimental conditions (blade velocity, evaporation rate, temperature, etc…). This liquid coating technique is a well-known, non-expensive technique to realize thin film coatings on various substrates. For coatings on glass substrates destined to solar insulation applications, the ideal coating would be made of a material able to transmit all the visible range while reflecting the NIR range perfectly, but materials possessing similar properties still have unsatisfactory opacity in the visible too (for example, titanium dioxide nanoparticles). NIR absorbing thin films is a more realistic alternative for such an application. Under solar illumination, PEDOT: PSS thin films heat up due to absorption of NIR light and thus act as planar heaters while maintaining good transparency in the visible range. Whereas they screen some NIR radiation, they also generate heat which is then conducted into the substrate that re-emits this energy by thermal emission in every direction. In order to quantify the heating power of these coatings, a sample (coating on glass) is placed in a black enclosure and illuminated with a solar simulator, a lamp emitting a calibrated radiation very similar to the solar spectrum. The temperature of the rear face of the substrate is measured in real-time using thermocouples and a black-painted Peltier sensor measures the total entering flux (sum of transmitted and re-emitted fluxes). The heating power density of the thin films is estimated from a model of the thin film/glass substrate describing the system, and we estimate the Solar Heat Gain Coefficient (SHGC) to quantify the light-to-heat conversion efficiency of such systems. Eventually, the effect of additives such as dimethyl sulfoxide (DMSO) or optical scatterers (particles) on the performances are also studied, as the first one can alter the IR absorption properties of PEDOT: PSS drastically and the second one can increase the apparent optical path of light within the thin film material.

Keywords: PEDOT: PSS, blade-coating, heat, thin-film, Solar spectrum

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Authors: Cristina Costescu, Carmen David, Adrian Roșan

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Executive functions (EF) and emotion regulation strategies are processes that allow individuals to function in an adaptative way and to be goal-oriented, which is essential for success in daily living activities, at school, or in social contexts. The Emotion Regulation and Executive Functioning Scale for Children and Adolescents (REMEX) represents an empirically based tool (based on the model of EF developed by Diamond) for evaluating significant dimensions of child and adolescent EFs and emotion regulation strategies, mainly in school contexts. The instrument measures the following dimensions: working memory, inhibition, cognitive flexibility, executive attention, planning, emotional control, and emotion regulation strategies. Building the instrument involved not only a top-down process, as we selected the content in accordance with prominent models of FE, but also a bottom-up one, as we were able to identify valid contexts in which FE and ER are put to use. For the construction of the instrument, we implemented three focus groups with teachers and other professionals since the aim was to develop an accurate, objective, and ecological instrument. We used the focus group method in order to address each dimension and to yield a bank of items to be further tested. Each dimension is addressed through a task that the examiner will apply and through several items derived from the main task. For the validation of the instrument, we plan to use item response theory (IRT), also known as the latent response theory, that attempts to explain the relationship between latent traits (unobservable cognitive processes) and their manifestations (i.e., observed outcomes, responses, or performance). REMEX represents an ecological scale that integrates a current scientific understanding of emotion regulation and EF and is directly applicable to school contexts, and it can be very useful for developing intervention protocols. We plan to test his convergent validity with the Childhood Executive Functioning Inventory (CHEXI) and Emotion Dysregulation Inventory (EDI) and divergent validity between a group of typically developing children and children with neurodevelopmental disorders, aged between 6 and 9 years old. In a previous pilot study, we enrolled a sample of 40 children with autism spectrum disorders and attention-deficit/hyperactivity disorder aged 6 to 12 years old, and we applied the above-mentioned scales (CHEXI and EDI). Our results showed that deficits in planning, bebavior regulation, inhibition, and working memory predict high levels of emotional reactivity, leading to emotional and behavioural problems. Considering previous results, we expect our findings to provide support for the validity and reliability of the REMEX version as an ecological instrument for assessing emotion regulation and EF in children and for key features of its uses in intervention protocols.

Keywords: executive functions, emotion regulation, children, item response theory, focus group

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Authors: Dalal Albudaiwi, Mike Allen, Talal Alhaji, Shahnaz Khadimehzadah

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As a pandemic, COVID-19 has impacted the whole world since November 2019. In other words, every organization, industry, and institution has been negatively affected by the Coronavirus. The uncertainty of how long the pandemic will last caused chaos at all levels. As with any other institution, public libraries were affected and transmitted into online services and resources. As internationally, have been witnessed that some public libraries were well-prepared for such disasters as the pandemic, and therefore, collections, users, services, technologies, staff, and budgets were all influenced. Public libraries’ policies did not mention any plan regarding such a pandemic. Instead, there are several rules in the guidelines about disasters in general, such as natural disasters. In this pandemic situation, libraries have been involved in different uneasy circumstances. However, it has always been apparent to public libraries the role they play in serving their communities in excellent and critical times. It dwells into the traditional role public libraries play in providing information services and sources to satisfy their information-based community needs. Remarkably increasing people’s awareness of the importance of informational enrichment and enhancing society’s skills in dealing with information and information sources. Under critical circumstances, libraries play a different role. It goes beyond the traditional part of information providers to the untraditional role of being a social institution that serves the community with whatever capabilities they have. This study takes two significant directions. The first focuses on investigating how libraries have responded to COVID-19 and how they manage disasters within their organization. The second direction focuses on how libraries help their communities to act during disasters and how to recover from the consequences. The current study examines how libraries prepare for disasters and the role of public libraries during disasters. We will also propose “measures” to be a model that libraries can use to evaluate the effectiveness of their response to disasters. We intend to focus on how libraries responded to this new disaster. Therefore, this study aims to develop a comprehensive policy that includes responding to a crisis such as Covid-19. An analytical lens inside the libraries as an organization and outside the organization walls will be documented based on analyzing disaster-related literature published in the LIS publication. The study employs content analysis (CA) methodology. CA is widely used in the library and information science. The critical contribution of this work is to propose solutions it provides to libraries and planers to prepare crisis management plans/ policies, specifically to face a new global disaster such as the COVID-19 pandemic. Moreover, the study will help library directors to evaluate their strategies and to improve them properly. The significance of this study lies in guiding libraries’ directors to enhance the goals of the libraries to guarantee crucial issues such as: saving time, avoiding loss, saving budget, acting quickly during a crisis, maintaining libraries’ role during pandemics, finding out the best response to disasters, and creating plan/policy as a sample for all libraries.

Keywords: Covid-19, policy, preparedness, public libraries

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Authors: Irene Capecchi, Tommaso Borghini, Iacopo Bernetti

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One of the most common pieces of equipment still used today for pruning, felling, and processing trees is the chainsaw in forestry. However, chainsaw use highlights dangers and one of the highest rates of accidents in both professional and non-professional work. Felling is proportionally the most dangerous phase, both in severity and frequency, because of the risk of being hit by the plant the operator wants to cut down. To avoid this, a correct sequence of chainsaw cuts must be taught concerning the different conditions of the tree. Virtual reality (VR) makes it possible to virtually simulate chainsaw use without danger of injury. The limitations of the existing applications are as follow. The existing platforms are not symmetrical collaborative because the trainee is only in virtual reality, and the trainer can only see the virtual environment on a laptop or PC, and this results in an inefficient teacher-learner relationship. Therefore, most applications only involve the use of a virtual chainsaw, and the trainee thus cannot feel the real weight and inertia of a real chainsaw. Finally, existing applications simulate only a few cases of tree felling. The objectives of this research were to implement and test a symmetrical collaborative training application based on VR and mixed reality (MR) with the overlap between real and virtual chainsaws in MR. The research and training platform was developed for the Meta quest 2 head-mounted display. The research and training platform application is based on the Unity 3D engine, and Present Platform Interaction SDK (PPI-SDK) developed by Meta. PPI-SDK avoids the use of controllers and enables hand tracking and MR. With the combination of these two technologies, it was possible to overlay a virtual chainsaw with a real chainsaw in MR and synchronize their movements in VR. This ensures that the user feels the weight of the actual chainsaw, tightens the muscles, and performs the appropriate movements during the test allowing the user to learn the correct body posture. The chainsaw works only if the right sequence of cuts is made to felling the tree. Contact detection is done by Unity's physics system, which allows the interaction of objects that simulate real-world behavior. Each cut of the chainsaw is defined by a so-called collider, and the felling of the tree can only occur if the colliders are activated in the right order simulating a safe technique felling. In this way, the user can learn how to use the chainsaw safely. The system is also multiplayer, so the student and the instructor can experience VR together in a symmetrical and collaborative way. The platform simulates the following tree-felling situations with safe techniques: cutting the tree tilted forward, cutting the medium-sized tree tilted backward, cutting the large tree tilted backward, sectioning the trunk on the ground, and cutting branches. The application is being evaluated on a sample of university students through a special questionnaire. The results are expected to test both the increase in learning compared to a theoretical lecture and the immersive and telepresence of the platform.

Keywords: chainsaw, collaborative symmetric virtual reality, mixed reality, operator training

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Authors: T. Vijay Bhasker, N. K. S Gowda, P. Krishnamoorthy, D. T. Pal, A. K. Pattanaik, A. K. Verma

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Boron (B) is a newer trace element and its biological importance and dietary essentiality is unclear in animals. The available literature suggests its putative role in bone mineralization, antioxidant status and steroid hormone synthesis. A feeding trial was conducted in Wister strain (Rattus norvegicus) albino rats for duration of 90 days. A total of 84 healthy weaned (3-4 weeks) experimental rats were randomly divided into 7 dietary groups (4 replicates of three each) viz., A (Basal diet/ Control), B (Basal diet + 5 ppm B), C (Basal diet + 10 ppm B), D (Basal diet + 20 ppm B), E (Basal diet + 40 ppm B), F (Basal diet-Ca 50%), G (Basal diet-Ca 50% + 40 ppm B). Dietary level of calcium (Ca) was maintained at two levels, 100% and 50% of requirement. Sodium borate was used as source of boron along with other ingredients of basal diet while preparing the pelletized diets. All the rats were kept in proper ventilated laboratory animal house maintained at temperature (23±2º C) and humidity (50 to 70%). At the end of experiment digestibility trial was conducted for 5 days to estimate nutrient digestibility and gut absorption of minerals. Eight rats from each group were sacrificed to collect the vital organs (liver, kidney and spleen) to study histopathology. Blood sample was drawn by heart puncture to determine biochemical profile. The average daily feed intake (g/rat/day), water intake (ml/rat/day) and body weight gain (g/rat/day) were similar among the dietary groups. The digestibility (%) of organic matter and crude fat were significantly improved (P < 0.05) was by B supplementation. The gut absorption (%) Ca was significantly increased (P < 0.01) in B supplemented groups compared to control. However, digestibility of dry matter and crude protein, gut absorption of magnesium and phosphorus showed a non-significant increasing trend with B supplementation. The gut absorption (%) of B (P < 0.01) was significantly lowered (P<0.05) in supplemented groups compared to un-supplemented ones. The serum level of triglycerides (mg/dL), HDL-cholesterol (mg/dL) and alanine transaminase (IU/L) were significantly lowered (P < 0.05) in B supplemented groups. While serum level of glucose (mg/dL) and alkaline phosphatase (KA units) showed a non-significant decreasing trend with B supplementation. However the serum levels of total cholesterol (mg/dL) and aspartate transaminase (IU/L) were similar among dietary groups. The histology sections of kidney and spleen revealed no significant changes among the dietary groups and were observed to be normal in anatomical architecture. However, the liver histology revealed cell degenerative changes with vacuolar degeneration and nuclear condensation in Ca deficient groups. But the comparative degenerative changes were mild in 40 ppm B supplemented Ca deficient group. In conclusion, dietary supplementation of graded levels of boron in rats had a positive effect on metabolism and health by improving nutrient digestibility and gut absorption of Ca. This indicates the beneficial role of dietary boron supplementation.

Keywords: boron, calcium, nutrient utilization, histopathology

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Authors: Esra Yuksel, Dilek Duman, Levent Yeniay, Sezgin Ulukaya

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Sentinel lymph node biopsy (SLNB) is a minimal invasive technique with lower morbidity in axillary staging of breast cancer. Isosulfan blue stain is frequently used in SLNB and regarded as safe. The present case report aimed to report severe decrement in SpO2 following isosulfan blue administration, as well as skin and urine signs and inconsistency with clinical picture in a 67-year-old ,77 kg, ASA II female case that underwent SLNB under general anesthesia. Ten minutes after subcutaneous administration of 10 ml 1% isosulfan blue by the surgeons into the patient, who were hemodynamically stable, SpO2 first reduced to 87% from 99%, and then to 75% in minutes despite 100% oxygen support. Meanwhile, blood pressure and EtCO2 monitoring was unremarkable. After specifying that anesthesia device worked normally, airway pressure did not increase and the endotracheal tube has been placed accurately, the blood sample was taken from the patient for arterial gas analysis. A severe increase was thought in MetHb concentration since SpO2 persisted to be 75% although the concentration of inspired oxygen was 100%, and solution of 2500 mg ascorbic acid in 500 ml 5% Dextrose was given to the patient via intravenous route until the results of arterial blood gas were obtained. However, arterial blood gas results were as follows: pH: 7.54, PaCO2: 23.3 mmHg, PaO2: 281 mmHg, SaO2: %99, and MetHb: %2.7. Biochemical analysis revealed a blood MetHb concentration of 2%.However, since arterial blood gas parameters were good, hemodynamics of the patient was stable and methemoglobin concentration was not so high, the patient was extubated after surgery when she was relaxed, cooperated and had adequate respiration. Despite the absence of respiratory or neurological distress, SpO2 value was increased only up to 85% within 2 hours with 5 L/min oxygen support via face mask in the surgery room as the patient was extubated. At that time, the skin of particularly the upper part of her body has turned into blue, more remarkable on the face. The color of plasma of the blood taken from the patient for biochemical analysis was blue. The color of urine coming throughout the urinary catheter placed in intensive care unit was also blue. Twelve hours after 5 L/min. oxygen inhalation via a mask, the SpO2 reached to 90%. During monitoring in intensive care unit on the postoperative 1st day, facial color and urine color of the patient was still blue, SpO2 was 92%, and arterial blood gas levels were as follows: pH: 7.44, PaO2: 76.1 mmHg, PaCO2: 38.2 mmHg, SaO2: 99%, and MetHb 1%. During monitoring in clinic on the postoperative 2nd day, SpO2 was 95% without oxygen support and her facial and urine color turned into normal. The patient was discharged on the 3rd day without any problem.In conclusion, SLNB is a less invasive alternative to axillary dissection. However, false pulse oximeter reading due to pigment interference is a rare complication of this procedure. Arterial blood gas analysis should be used to confirm any fall in SpO2 reading during monitoring.

Keywords: isosulfan blue, pulse oximetry, SLNB, methemoglobinemia

Procedia PDF Downloads 315

Authors: Shirley S. Ho

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The advancement and development of social media have inadvertently brought about a new form of bullying – cyberbullying – that transcends across physical boundaries of space. Although extensive research has been conducted in the field of cyberbullying, most of these studies have taken an overwhelmingly empirical angle. Theories guiding cyberbullying research are few. Furthermore, very few studies have explored the association between parental mediation and cyberbullying, with majority of existing studies focusing on cyberbullying victimization rather than perpetration. Therefore, this present study investigates cyberbullying perpetration from a theoretical angle, with a focus on the Theory of Reasoned Action and the Parental Mediation Theory. More specifically, this study examines the direct effects of attitude, subjective norms, descriptive norms, injunctive norms and active mediation and restrictive mediation on cyberbullying perpetration on social media among children and adolescents in Singapore. Furthermore, the moderating role of age on the relationship between parental mediation and cyberbullying perpetration on social media are examined. A self-administered paper-and-pencil nationally-representative survey was conducted. Multi-stage cluster random sampling was used to ensure that schools from all the four (North, South, East, and West) regions of Singapore were equally represented in the sample used for the survey. In all 607 upper primary school children (i.e., Primary 4 to 6 students) and 782 secondary school adolescents participated in our survey. The total average response rates were 69.6% for student participation. An ordinary least squares hierarchical regression analysis was conducted to test the hypotheses and research questions. The results revealed that attitude and subjective norms were positively associated with cyberbullying perpetration on social media. Descriptive norms and injunctive norms were not found to be significantly associated with cyberbullying perpetration. The results also showed that both parental mediation strategies were negatively associated with cyberbullying perpetration on social media. Age was a significant moderator of both parental mediation strategies and cyberbullying perpetration. The negative relationship between active mediation and cyberbullying perpetration was found to be greater in the case of children than adolescents. Children who received high restrictive parental mediation were less likely to perform cyberbullying behaviors, while adolescents who received high restrictive parental mediation were more likely to be engaged in cyberbullying perpetration. The study reveals that parents should apply active mediation and restrictive mediation in different ways for children and adolescents when trying to prevent cyberbullying perpetration. The effectiveness of active parental mediation for reducing cyberbullying perpetration was more in the case of children than for adolescents. Younger children were found to be more likely to respond more positively toward restrictive parental mediation strategies, but in the case of adolescents, overly restrictive control was found to increase cyberbullying perpetration. Adolescents exhibited less cyberbullying behaviors when under low restrictive strategies. Findings highlight that the Theory of Reasoned Action and Parental Mediation Theory are promising frameworks to apply in the examination of cyberbullying perpetration. The findings that different parental mediation strategies had differing effectiveness, based on the children’s age, bring about several practical implications that may benefit educators and parents when addressing their children’s online risk.

Keywords: cyberbullying perpetration, theory of reasoned action, parental mediation, social media, Singapore

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Authors: Ana Flavia Belchior De Andrade

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Forensic laboratories all over the world face a great challenge to overcame waiting time and backlog in many different areas. Many aspects contribute to this situation, such as an increase in drug complexity, increment in the number of exams requested and cuts in funding limiting laboratories hiring capacity. Altogether, those facts pose an essential challenge for forensic chemistry laboratories to keep both quality and time of response within an acceptable period. In this paper we will analyze how the backlog affects test results and, in the end, the whole judicial system. In this study data from marijuana samples seized by the Federal District Civil Police in Brazil between the years 2013 and 2017 were tabulated and the results analyzed and discussed. In the last five years, the number of petitioned exams increased from 822 in February 2013 to 1358 in March 2018, representing an increase of 32% in 5 years, a rise of more than 6% per year. Meanwhile, our data shows that the number of performed exams did not grow at the same rate. Product numbers are stationed as using the actual technology scenario and analyses routine the laboratory is running in full capacity. Marijuana detection is the most prevalence exam required, representing almost 70% of all exams. In this study, data from 7,110 (seven thousand one hundred and ten) marijuana samples were analyzed. Regarding waiting time, most of the exams were performed not later than 60 days after receipt (77%). Although some samples waited up to 30 months before being examined (0,65%). When marijuana´s exam is delayed we notice the enlargement of inconclusive results using thin-layer chromatography (TLC). Our data shows that if a marijuana sample is stored for more than 18 months, inconclusive results rise from 2% to 7% and when if storage exceeds 30 months, inconclusive rates increase to 13%. This is probably because Cannabis plants and preparations undergo oxidation under storage resulting in a decrease in the content of Δ9-tetrahydrocannabinol ( Δ9-THC). An inconclusive result triggers other procedures that require at least two more working hours of our analysts (e.g., GC/MS analysis) and the report would be delayed at least one day. Those new procedures increase considerably the running cost of a forensic drug laboratory especially when the backlog is significant as inconclusive results tend to increase with waiting time. Financial aspects are not the only ones to be observed regarding backlog cases; there are also social issues as legal procedures can be delayed and prosecution of serious crimes can be unsuccessful. Delays may slow investigations and endanger public safety by giving criminals more time on the street to re-offend. This situation also implies a considerable cost to society as at some point, if the exam takes a long time to be performed, an inconclusive can turn into a negative result and a criminal can be absolved by flawed expert evidence.

Keywords: backlog, forensic laboratory, quality management, accreditation

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Authors: G. Bruno, A. Ciavarella, N. Linciano

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The proportion of women in boardroom has traditionally been low around the world. Over the last decades, several jurisdictions opted for active intervention, which triggered a tangible progress in female representation. In Europe, many countries have implemented boardroom diversity policies in the form of legal quotas (Norway, Italy, France, Germany) or governance code amendments (United Kingdom, Finland). Policy actions rest, among other things, on the assumption that gender balanced boards result in improved corporate governance and performance. The investigation of the relationship between female boardroom representation and firm value is therefore key on policy grounds. The evidence gathered so far, however, has not produced conclusive results also because empirical studies on the impact of voluntary female board representation had to tackle with endogeneity, due to either differences in unobservable characteristics across firms that may affect their gender policies and governance choices, or potential reverse causality. In this paper, we study the relationship between the presence of female directors and corporate performance in Italy, where the Law 120/2011 envisaging mandatory quotas has introduced an exogenous shock in board composition which may enable to overcome reverse causality. Our sample comprises Italian firms listed on the Italian Stock Exchange and the members of their board of directors over the period 2008-2016. The study relies on two different databases, both drawn from CONSOB, referring respectively to directors and companies’ characteristics. On methodological grounds, information on directors is treated at the individual level, by matching each company with its directors every year. This allows identifying all time-invariant, possibly correlated, elements of latent heterogeneity that vary across firms and board members, such as the firm immaterial assets and the directors’ skills and commitment. Moreover, we estimate dynamic panel data specifications, so accommodating non-instantaneous adjustments of firm performance and gender diversity to institutional and economic changes. In all cases, robust inference is carried out taking into account the bidimensional clustering of observations over companies and over directors. The study shows the existence of a U-shaped impact of the percentage of women in the boardroom on profitability, as measured by Return On Equity (ROE) and Return On Assets. Female representation yields a positive impact when it exceeds a certain threshold, ranging between about 18% and 21% of the board members, depending on the specification. Given the average board size, i.e., around ten members over the time period considered, this would imply that a significant effect of gender diversity on corporate performance starts to emerge when at least two women hold a seat. This evidence supports the idea underpinning the critical mass theory, i.e., the hypothesis that women may influence.

Keywords: gender diversity, quotas, firms performance, corporate governance

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Authors: Majid Hejazian, Nam-Trung Nguyen

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Over the past few years, microfluidic devices have generated significant attention from industry and academia due to advantages such as small sample volume, low cost and high efficiency. Microfluidic devices have applications in chemical, biological and industry analysis and can facilitate assay of bio-materials and chemical reactions, separation, and sensing. Micromixers are one of the important microfluidic concepts. Micromixers can work as stand-alone devices or be integrated in a more complex microfluidic system such as a lab on a chip (LOC). Micromixers are categorized as passive and active types. Passive micromixers rely only on the arrangement of the phases to be mixed and contain no moving parts and require no energy. Active micromixers require external fields such as pressure, temperature, electric and acoustic fields. Rapid and efficient mixing is important for many applications such as biological, chemical and biochemical analysis. Achieving fast and homogenous mixing of multiple samples in the microfluidic devices has been studied and discussed in the literature recently. Improvement in mixing rely on effective mass transport in microscale, but are currently limited to molecular diffusion due to the predominant laminar flow in this size scale. Using magnetic field to elevate mass transport is an effective solution for mixing enhancement in microfluidics. The use of a non-uniform magnetic field to improve mass transfer performance in a microfluidic device is demonstrated in this work. The phenomenon of mixing ferrofluid and DI-water streams has been reported before, but mass transfer enhancement for other non-magnetic species through magnetic field have not been studied and evaluated extensively. In the present work, permanent magnets were used in a simple microfluidic device to create a non-uniform magnetic field. Two streams are introduced into the microchannel: one contains fluorescent dye mixed with diluted ferrofluid to induce enhanced mass transport of the dye, and the other one is a non-magnetic DI-water stream. Mass transport enhancement of fluorescent dye is evaluated using fluorescent measurement techniques. The concentration field is measured for different flow rates. Due to effect of magnetic field, a body force is exerted on the paramagnetic stream and expands the ferrofluid stream into non-magnetic DI-water flow. The experimental results demonstrate that without a magnetic field, both magnetic nanoparticles of the ferrofluid and the fluorescent dye solely rely on molecular diffusion to spread. The non-uniform magnetic field, created by the permanent magnets around the microchannel, and diluted ferrofluid can improve mass transport of non-magnetic solutes in a microfluidic device. The susceptibility mismatch between the fluids results in a magnetoconvective secondary flow towards the magnets and subsequently the mass transport of the non-magnetic fluorescent dye. A significant enhancement in mass transport of the fluorescent dye was observed. The platform presented here could be used as a microfluidics-based micromixer for chemical and biological applications.

Keywords: ferrofluid, mass transfer, micromixer, microfluidics, magnetic

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Authors: Hanan Algarni

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Background: Impairment of walking and balance skills has negative impact on functional independence and community participation after stroke. Gait recovery is considered a primary goal in rehabilitation by both patients and physiotherapists. Treadmill training coupled with virtual reality technology is a new emerging approach that offers patients with feedback, open and random skills practice while walking and interacting with virtual environmental scenes. Objectives: To synthesize the evidence around the effects of the VR treadmill training on gait speed and balance primarily, functional independence and community participation secondarily in stroke patients. Methods: Systematic review was conducted; search strategy included electronic data bases: MEDLINE, AMED, Cochrane, CINAHL, EMBASE, PEDro, Web of Science, and unpublished literature. Inclusion criteria: Participant: adult >18 years, stroke, ambulatory, without severe visual or cognitive impartments. Intervention: VR treadmill training alone or with physiotherapy. Comparator: any other interventions. Outcomes: gait speed, balance, function, community participation. Characteristics of included studies were extracted for analysis. Risk of bias assessment was performed using Cochrane's ROB tool. Narrative synthesis of findings was undertaken and summary of findings in each outcome was reported using GRADEpro. Results: Four studies were included involving 84 stroke participants with chronic hemiparesis. Interventions intensity ranged (6-12 sessions, 20 minutes-1 hour/session). Three studies investigated the effects on gait speed and balance. 2 studies investigated functional outcomes and one study assessed community participation. ROB assessment showed 50% unclear risk of selection bias and 25% of unclear risk of detection bias across the studies. Heterogeneity was identified in the intervention effects at post training and follow up. Outcome measures, training intensity and durations also varied across the studies, grade of evidence was low for balance, moderate for speed and function outcomes, and high for community participation. However, it is important to note that grading was done on few numbers of studies in each outcome. Conclusions: The summary of findings suggests positive and statistically significant effects (p<0.05) of VR treadmill training compared to other interventions on gait speed, dynamic balance skills, function and participation directly after training. However, the effects were not sustained at follow up in two studies (2 weeks-1 month) and other studies did not perform follow up measurements. More RCTs with larger sample sizes and higher methodological quality are required to examine the long term effects of VR treadmill effects on function independence and community participation after stroke, in order to draw conclusions and produce stronger robust evidence.

Keywords: virtual reality, treadmill, stroke, gait rehabilitation

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Authors: Vineeta Sirohi

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The development of critical skills and competencies becomes imperative for young people to cope with the unpredicted challenges of the time and prepare for work and life. Recognizing that education has a critical role in reaching sustainability goals as emphasized by 2030 agenda for sustainability development, educating youth in global competence, meta-cognitive competencies, and skills from the initial stages of formal education are vital. Further, educating for global competence would help in developing work readiness and boost employability. Vocational education and training in India as envisaged in various policy documents remain marginalized in practice as compared to general education. The country is still far away from the national policy goal of tracking 25% of the secondary students at grade eleven and twelve under the vocational stream. In recent years, the importance of skill development has been recognized in the present context of globalization and change in the demographic structure of the Indian population. As a result, it has become a national policy priority and taken up with renewed focus by the government, which has set the target of skilling 500 million people by 2022. This paper provides an overview of the policies, practices, and current status of vocational education and training in India supported by statistics from the National Sample Survey, the official statistics of India. The national policy documents and annual reports of the organizations actively involved in vocational education and training have also been examined to capture relevant data and information. It has also highlighted major initiatives taken by the government to promote skill development. The data indicates that in the age group 15-59 years, only 2.2 percent reported having received formal vocational training, and 8.6 percent have received non-formal vocational training, whereas 88.3 percent did not receive any vocational training. At present, the coverage of vocational education is abysmal as less than 5 percent of the students are covered by the vocational education programme. Besides, launching various schemes to address the mismatch of skills supply and demand, the government through its National Policy on Skill Development and Entrepreneurship 2015 proposes to bring about inclusivity by bridging the gender, social and sectoral divide, ensuring that the skilling needs of socially disadvantaged and marginalized groups are appropriately addressed. It is fundamental that the curriculum is aligned with the demands of the labor market, incorporating more of the entrepreneur skills. Creating nonfarm employment opportunities for educated youth will be a challenge for the country in the near future. Hence, there is a need to formulate specific skill development programs for this sector and also programs for upgrading their skills to enhance their employability. There is a need to promote female participation in work and in non-traditional courses. Moreover, rigorous research and development of a robust information base for skills are required to inform policy decisions on vocational education and training.

Keywords: policy, skill, training, vocational education

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Authors: Natalia V. Beloglazova, Pieterjan Lenain, Martin Hedstrom, Dietmar Knopp, Sarah De Saeger

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In recent years polycyclic aromatic hydrocarbons (PAHs), which represent a hazard to humans and entire ecosystem, have been receiving an increased interest due to their mutagenic, carcinogenic and endocrine disrupting properties. They are formed in all incomplete combustion processes of organic matter and, as a consequence, ubiquitous in the environment. Benzo(a)pyrene (BaP) is on the priority list published by the Environmental Agency (US EPA) as the first PAH to be identified as a carcinogen and has often been used as a marker for PAHs contamination in general. It can be found in different types of water samples, therefore, the European Commission set up a limit value of 10 ng L–1 (10 ppt) for BAP in water intended for human consumption. Generally, different chromatographic techniques are used for PAHs determination, but these assays require pre-concentration of analyte, create large amounts of solvent waste, and are relatively time consuming and difficult to perform on-site. An alternative robust, stand-alone, and preferably cheap solution is needed. For example, a sensing unit which can be submerged in a river to monitor and continuously sample BaP. An affinity sensor based on capacitive transduction was developed. Natural antibodies or their synthetic analogues can be used as ligands. Ideally the sensor should operate independently over a longer period of time, e.g. several weeks or months, therefore the use of molecularly imprinted polymers (MIPs) was discussed. MIPs are synthetic antibodies which are selective for a chosen target molecule. Their robustness allows application in environments for which biological recognition elements are unsuitable or denature. They can be reused multiple times, which is essential to meet the stand-alone requirement. BaP is a highly lipophilic compound and does not contain any functional groups in its structure, thus excluding non-covalent imprinting methods based on ionic interactions. Instead, the MIPs syntheses were based on non-covalent hydrophobic and π-π interactions. Different polymerization strategies were compared and the best results were demonstrated by the MIPs produced using electropolymerization. 4-vinylpyridin (VP) and divinylbenzene (DVB) were used as monomer and cross-linker in the polymerization reaction. The selectivity and recovery of the MIP were compared to a non-imprinted polymer (NIP). Electrodes were functionalized with natural receptor (monoclonal anti-BaP antibody) and with MIPs selective towards BaP. Different sets of electrodes were evaluated and their properties such as sensitivity, selectivity and linear range were determined and compared. It was found that both receptor can reach the cut-off level comparable to the established ML, and despite the fact that the antibody showed the better cross-reactivity and affinity, MIPs were more convenient receptor due to their ability to regenerate and stability in river till 7 days.

Keywords: antibody, benzo(a)pyrene, capacitive sensor, MIPs, river water

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Authors: Keping Zuo, Jia Yin Chia, Gideon Praveen Kumar Vijayakumar, Foad Kabinejadian, Fangsen Cui, Pei Ho, Hwa Liang Leo

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Carotid artery is the major vessel supplying blood to the brain. Carotid artery stenosis is one of the three major causes of stroke and the stroke is the fourth leading cause of death and the first leading cause of disability in most developed countries. Although there is an increasing interest in carotid artery stenting for treatment of cervical carotid artery bifurcation therosclerotic disease, currently available bare metal stents cannot provide an adequate protection against the detachment of the plaque fragments over diseased carotid artery, which could result in the formation of micro-emboli and subsequent stroke. Our research group has recently developed a novel preferential covered-stent for carotid artery aims to prevent friable fragments of atherosclerotic plaques from flowing into the cerebral circulation, and yet retaining the ability to preserve the flow of the external carotid artery. The preliminary animal studies have demonstrated the potential of this novel covered-stent design for the treatment of carotid therosclerotic stenosis. The purpose of this study is to evaluate the biomechanical property of PU membrane of different concentration configurations in order to refine the stent coating technique and enhance the clinical performance of our novel carotid covered stent. Results from this study also provide necessary material property information crucial for accurate simulation analysis for our stents. Method: Medical grade Polyurethane (ChronoFlex AR) was used to prepare PU membrane specimens. Different PU membrane configurations were subjected to uniaxial test: 22%, 16%, and 11% PU solution were made by mixing the original solution with proper amount of the Dimethylacetamide (DMAC). The specimens were then immersed in physiological saline solution for 24 hours before test. All specimens were moistened with saline solution before mounting and subsequent uniaxial testing. The specimens were preconditioned by loading the PU membrane sample to a peak stress of 5.5 Mpa for 10 consecutive cycles at a rate of 50 mm/min. The specimens were then stretched to failure at the same loading rate. Result: The results showed that the stress-strain response curves of all PU membrane samples exhibited nonlinear characteristic. For the ultimate failure stress, 22% PU membrane was significantly higher than 16% (p<0.05). In general, our preliminary results showed that lower concentration PU membrane is stiffer than the higher concentration one. From the perspective of mechanical properties, 22% PU membrane is a better choice for the covered stent. Interestingly, the hyperelastic Ogden model is able to accurately capture the nonlinear, isotropic stress-strain behavior of PU membrane with R2 of 0.9977 ± 0.00172. This result will be useful for future biomechanical analysis of our stent designs and will play an important role for computational modeling of our covered stent fatigue study.

Keywords: carotid artery, covered stent, nonlinear, hyperelastic, stress, strain

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Authors: Kuo-Kai Lin, Po-Lun Chang

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Background: The Emergency Care Research Institute released a list for the top 10 medical technology hazards in 2017, with the following hazard topping the list: ‘infusion errors can be deadly if simple safety steps are overlooked.’ In addition, hospitals use various assessment items to evaluate the safety of their medical equipment, confirming the importance of medical equipment safety. In recent years, the topic of patient safety has garnered increasing attention. Accordingly, various agencies have established patient safety-related committees to coordinate, collect, and analyze information regarding abnormal events associated with medical practice. Activities to promote and improve employee training have been introduced to diminish the recurrence of medical malpractice. Objective: To allow nursing personnel to acquire the skills needed to operate common medical equipment and update and review such skills whenever necessary to elevate medical care quality and reduce patient injuries caused by medical equipment operation errors. Method: In this study, a quasi-experimental design was adopted and nurses from a regional teaching hospital were selected as the study sample. Online videos instructing the operation method of common medical equipment were made and quick response codes were designed for the nursing personnel to quickly access the videos when necessary. Senior nursing supervisors and equipment experts were invited to formulate a ‘Scale-based Questionnaire for Assessing Nursing Personnel’s Operational Knowledge of Common Medical Equipment’ to evaluate the nursing personnel’s literacy regarding the operation of the medical equipment. From March to October 2017, an employee training on medical equipment operation and a practice course (simulation course) were implemented, after which the effectiveness of the training and practice course were assessed. Results: Prior to and after the training and practice course, the 66 participating nurses scored 58 and 87 on ‘operational knowledge of common medical equipment,’ respectively (showing a significant statistical difference; t = -9.407, p < .001); 53.5 and 86.3 on ‘operational knowledge of 12-lead electrocardiography’ (z = -2.087, p < .01), respectively; 40 and 79.5 on ‘operational knowledge of cardiac defibrillators’ (z = -3.849, p < .001), respectively; 90 and 98 on ‘operational knowledge of Abbott pumps’ (z = -1.841, p = 0.066), respectively; and 8.7 and 13.7 on ‘perceived competence’ (showing a significant statistical difference; t = -2.77, p < .05). In the participating hospital, medical equipment operation errors were observed in both 2016 and 2017. However, since the implementation of the intervention, medical equipment operation errors have not yet been observed up to October 2017, which can be regarded as the secondary outcome of this study. Conclusion: In this study, innovative teaching strategies were adopted to effectively enhance the professional literacy and skills of nursing personnel in operating medical equipment. The training and practice course also elevated the nursing personnel’s related literacy and perceived competence of operating medical equipment. The nursing personnel was thus able to accurately operate the medical equipment and avoid operational errors that might jeopardize patient safety.

Keywords: medical equipment, digital teaching plan, simulation-based teaching plan, operational knowledge, patient safety

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Authors: Hande Yavuz, Grégory Girard, Jinbo Bai

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Manufacturing of hybrid composites requires particular attention to overcome various critical weaknesses that are originated from poor interfacial compatibility. A large number of parameters have to be considered to optimize the interfacial bond strength either to avoid flaw sensitivity or delamination that occurs in composites. For this reason, surface characterization of reinforcement phase is needed in order to provide necessary data to drive an assessment of fiber-matrix interfacial compatibility prior to fabrication of composite structures. Compared to conventional plasma polymerization processes such as radiofrequency and microwave, dielectric barrier discharge assisted plasma polymerization is a promising process that can be utilized to modify the surface properties of carbon fibers in a continuous manner. Finding the most suitable conditions (e.g., plasma power, plasma duration, precursor proportion) for plasma polymerization of pyrrole in post-discharge region either in the presence or in the absence of p-toluene sulfonic acid monohydrate as well as the characterization of plasma polypyrrole coated fibers are the important aspects of this work. Throughout the current investigation, atomic force microscopy (AFM) and thermogravimetric analysis (TGA) are used to characterize plasma treated hybrid fibers (CNT-grafted Toray T700-12K carbon fibers, referred as T700/CNT). TGA results show the trend in the change of decomposition process of deposited polymer on fibers as a function of temperature up to 900 °C. Within the same period of time, all plasma pyrrole treated samples began to lose weight with relatively fast rate up to 400 °C which suggests the loss of polymeric structures. The weight loss between 300 and 600 °C is attributed to evolution of CO2 due to decomposition of functional groups (e.g. carboxyl compounds). With keeping in mind the surface chemical structure, the higher the amount of carbonyl, alcohols, and ether compounds, the lower the stability of deposited polymer. Thus, the highest weight loss is observed in 1400 W 45 s pyrrole+pTSA.H2O plasma treated sample probably because of the presence of less stable polymer than that of other plasma treated samples. Comparison of the AFM images for untreated and plasma treated samples shows that the surface topography may change on a microscopic scale. The AFM image of 1800 W 45 s treated T700/CNT fiber possesses the most significant increase in roughening compared to untreated T700/CNT fiber. Namely, the fiber surface became rougher with ~3.6 fold that of the T700/CNT fiber. The increase observed in surface roughness compared to untreated T700/CNT fiber may provide more contact points between fiber and matrix due to increased surface area. It is believed to be beneficial for their application as reinforcement in composites.

Keywords: hybrid fibers, surface characterization, surface roughness, thermal stability

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