Search results for: stress fracture

Authors: G. Amariei, K. Boltes, R. Rosal, P. Leton

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Wastewater treatment plants (WWTPs) are supposed to hold an important place in the reduction of emerging contaminants, but provide an environment that has potential for the development and/or spread of adaptation, as bacteria are continuously mixed with contaminants at sub-inhibitory concentrations. Reviewing the literature, there are little data available regarding the use of adapted bacteria forming activated sludge community for toxicity assessment, and only individual validations have been performed. Therefore, the aim of this work was to study the toxicity of Triclosan (TCS) and Ibuprofen (IBU), individually and in binary combination, on adapted activated sludge (AS). For this purpose a battery of biomarkers were assessed, involving oxidative stress and cytotoxicity responses: glutation-S-transferase (GST), catalase (CAT) and viable cells with FDA. In addition, we compared the toxic effects on adapted bacteria with unadapted bacteria, from a previous research. Adapted AS comes from three continuous-flow AS laboratory systems; two systems received IBU and TCS, individually; while the other received the binary combination, for 14 days. After adaptation, each bacterial culture condition was exposure to IBU, TCS and the combination, at 12 h. The concentration of IBU and TCS ranged 0.5-4mg/L and 0.012-0.1 mg/L, respectively. Batch toxicity experiments were performed using Oxygraph system (Hansatech), for determining the activity of CAT enzyme based on the quantification of oxygen production rate. Fluorimetric technique was applied as well, using a Fluoroskan Ascent Fl (Thermo) for determining the activity of GST enzyme, using monochlorobimane-GSH as substrate, and to the estimation of viable cell of the sludge, by fluorescence staining using Fluorescein Diacetate (FDA). For IBU adapted sludge, CAT activity it was increased at low concentration of IBU, TCS and mixture. However, increasing the concentration the behavior was different: while IBU tends to stabilize the CAT activity, TCS and the mixture decreased this one. GST activity was significantly increased by TCS and mixture. For IBU, no variations it was observed. For TCS adapted sludge, no significant variations on CAT activity it was observed. GST activity it was significant decreased for all contaminants. For mixture adapted sludge the behaviour of CAT activity it was similar to IBU adapted sludge. GST activity it was decreased at all concentration of IBU. While the presence of TCS and mixture, respectively, increased the GST activity. These findings were consistent with the viability cells evaluation, which clearly showed a variation of sludge viability. Our results suggest that, compared with unadapted bacteria, the adapted bacteria conditions plays a relevant role in the toxicity behaviour towards activated sludge communities.

Keywords: adapted sludge community, mixture, PPCPs, toxicity

Procedia PDF Downloads 399

Authors: Tonya P. Bowers

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Background: The community/patient-focused quality improvement (QI) project has resolved a clinical problem using a quantitative design evaluating behavior change practices in a convenience sample from a multi-cultural congregation in a faith-based setting. AD is a legal document that speaks for the patient when they are unable to speak for themselves. The AD provides detailed information regarding critical medical decisions on behalf of the patient if they’re unable to make decisions themselves. The goal of an AD is to improve EOL care renderings that align with the patient’s desires. The AD diminishes anxiety and stress associated with making difficult EOL care decisions for patients and their families. Method: The project has two intervention strategies: pre-intervention and post-intervention formative surveys and a final summative survey. Most of the data collection takes place during implementation. The Let’s Talk About It Program utilized an online meeting platform for presentation. Participants were asked to complete informed consent and surveys via an online portal. Education included slide presentation, Advance Directive demonstration, video clips, discussions and 1:1 assistance with AD completion with a project manager. Results: Considering the overwhelming likelihood responses where 87.5% identified they “definitely would” hold an End-Of-Life conversation with their healthcare provider or family, and 81.25% indicated their likelihood that they “definitely would” complete an advance directive. In addition, the final summative post-intervention survey (n-14) also demonstrated an overwhelming 93% positive response. Which undoubtedly demonstrates favorable outcomes for the project. Conclusion: the Let’s Talk About It Program demonstrated effectiveness in improving participants' attitudes and acceptance towards Advance Directives and expanding End-of-Life care discussions. Emphasis on program sustainment within the church is imperative in fostering continued awareness and improved health outcomes for the local community with low health literacy.

Keywords: advance directive, end of life, advance care planning, palliative care, low health literacy, faith-based

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Authors: Mokgadi Malatji, Tebogo Mothiba, Rambelani Malema

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Absenteeism is a global problem in the working force and this is no exception in the nursing profession. A lot of attention has been drawn to factors that contribute to absenteeism however little attention has been placed on the effects of absenteeism on the remaining workers/nurses being left behind in the workplace by their colleagues. Nurses absent themselves leaving behind their colleagues to do their work. Nurses who are committed to their work often find themselves working under strenuous conditions due to inadequate staff. These may lead to poor patient care provision, nurses feeling overworked and sick due to the increased workload. The purpose of this study was to investigate the effects of absenteeism on nurses that remained at work at Mankweng Hospital in the Capricorn District, Limpopo Province. A descriptive cross-sectional quantitative research design was conducted to determine if there were any effects of absenteeism on nurses remaining at work. Data collection was done using structured questionnaires. The respondents (n=107), consisted of different categories of registered nurses (professional nurses (n=43), auxiliary nurses (n=40) and staff nurses (n=24)) who participated in this study. The findings indicated that most nurses (76, 6%) are demotivated and they struggle with completion of duties when their colleagues are absent. Patient care that nurses provided when their colleagues were absent was of poor quality as set standards and principles were not adhered to. Individualized patient care was not being implemented due to absenteeism. This simply implies that routine work is being done to cover basic duties. Most nurses (74, 8%) believed that favoritism and lack of appreciation of nurse’s skills and capabilities are being displayed by managers and that this contributes to absenteeism. Nurses who are loyal sacrifice their time and work overtime for absent colleagues and this led to fatigue and stress. From the study findings, it is recommended that nurses be trained frequently to upgrade their studies to motivate them to work. The government can provide this training to improve their skills as this will motivate nurses to work harder and be committed to their work. Training can be offered after a stipulated period. For example, after every five years, a nurse can be provided with a new skill. Team building events must be encouraged for the whole hospital to motivate staff. In conclusion, the study revealed that absenteeism poses detrimental effects on nurses, the hospital and patients. More and more nurses end up changing workplace due to these effects.

Keywords: absenteeism, effects, nurses, remaining at work

Procedia PDF Downloads 254

Authors: Akriti Kafle Baral, Ruixing Zhang, Dzifa K Lalit, Manthar M Alli

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Introduction: Hemodialysis is the most common type of dialysis globally approximately million are reported to receive this type of dialysis. Psychosocial issues in hemodialysis are the psychological and socioeconomic burdens emanating from the initiation and course of treatment and have the potential for gross deterioration in the quality of life and general well-being of patients. Understanding the psychosocial issues and needs of patients undergoing hemodialysis could pave the way for comprehensive support and therapies designed to reduce stress, improve social support, and foster mental resilience. Objectives: The aim of this study was to explore the psychosocial issues and support needs of patients undergoing hemodialysis at a tertiary care center in Nepal. Methods: A qualitative descriptive study was conducted among 20 purposefully selected patients attending hemodialysis treatment at Pokhara Academy of Health Sciences, Nepal. Data was analyzed via thematic analysis. Results: The study resulted in three major themes which included Emotional, psychological, and spiritual struggles, Social and economic impacts, and Support and information needs. Moreover, 16 sub-themes emerged which are Frustration with daily life, Constant fear of death, Thoughts of self-harm, Perceived Burden on Family, Sense of Divine Punishment, Sense of Unfairness, Fear about future uncertainties, Social avoidance, Social stigmatization, Loss of employment, Financial strain, Transportation challenges, Need for early, clear and comprehensive information, Need for support and reassurance from family, Support through peer connections, and Reassurance from healthcare providers. Conclusion: The findings of this study indicate that patients undergoing hemodialysis in Nepal experience numerous hardships and multifaceted struggles that require support from different dimensions. Establishing robust support systems that include family involvement, peer networks, and effective communication from healthcare professionals can significantly mitigate feelings of anxiety and isolation.

Keywords: hemodialysis, psychosocial issues, support needs, chronic kidney disease, end stage renal disease, Nepal

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Authors: Manahil Alfuraydan, Jodie Croxall, Lisa Hurt, Mike Kerr, Sinead Brophy

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Autism Spectrum Disorder (ASD) is a developmental condition characterised by impairment in terms of social communication, social interaction, and a repetitive or restricted pattern of interest, behaviour, and activity. There is a significant delay between seeking help and a confirmed diagnosis of ASD. This may result in delay in receiving early intervention services, which are critical for positive outcomes. The long wait times also cause stress for the individuals and their families. Telehealth potentially offers a way of improving the diagnostic pathway for ASD. This review of the literature aims to examine which telehealth approaches have been used in the diagnosis and assessment of autism in children and adults, whether they are feasible and acceptable, and how they compare with face-to-face diagnosis and assessment methods. A comprehensive search of following databases- MEDLINE, CINAHL Plus with Full text, Business Sources Complete, Web of Science, Scopus, PsycINFO and trail and systematic review databases including Cochrane Library, Health Technology Assessment, Database of Abstracts and Reviews of Effectiveness and NHS Economic Evaluation was conducted, combining the terms of autism and telehealth from 2000 to 2018. A total of 10 studies were identified for inclusion in the review. This review of the literature found there to be two methods of using telehealth: (a) video conferencing to enable teams in different areas to consult with the families and to assess the child/adult in real time and (b) a video upload to a web portal that enables the clinical assessment of behaviours in the family home. The findings were positive, finding there to be high agreement in terms of the diagnosis between remote methods and face to face methods and with high levels of satisfaction among the families and clinicians. This field is in the very early stages, and so only studies with small sample size were identified, but the findings suggest that there is potential for telehealth methods to improve assessment and diagnosis of autism used in conjunction with existing methods, especially for those with clear autism traits and adults with autism. Larger randomised controlled trials of this technology are warranted.

Keywords: assessment, autism spectrum disorder, diagnosis, telehealth

Procedia PDF Downloads 128

Authors: Maria Christine Rizzon Cintra, Tâmara Duarte Borges, Cristina Santos Sotomaior

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Lamb’s fleece quality can be influenced by many factors, including welfare, stress, nutritional imbalance and presence of ectoparasites. The association of fleece quality and endoparasitism, until now, was not well solved. The present study was undertaken to evaluate if a fleece visual score could predict lamb parasitosis with the focus on gastrointestinal parasites. Fleece quality was scored based on a combination of cleanliness and wool cover, using a three-point scale (1-3). Score 1: fleece shows no sign of dirt or contamination, and had sufficient fleece for the breed and time of year with whole body coverage; Score 2: fleece was little damp or wet, with coat contaminated by small patches of mud or dung and some areas of fleece loose, but no shed or bald patches of no more than 10cm in diameter; Score 3: fleece filthy, very wet with coated in mud or dug, and loose fleece with shed areas of pulls with bald patches greater than 10cm, some areas may be trailing. All fleece quality scores (FQS) were assessed with lamb restrained to ensure close inspection and were done along lamb back and considered just one side of the body. To confirm the gastrointestinal parasites and animal’s anemia, faecal egg counts (FEC) and hematocrit were done for each animal. Lambs were also weighed. All these measurements were done every 15-days, beginning at 60-days until 150-days of life, using 48 animals crossed Texel x Ile de France. For statistics analysis, it was used Stratigraphic Program (4.1. version), and all significant differences between FQS, weight gain, age, hematocrit, and FEC were assessed using analysis of variance following by Duncan test, and the correlation was done by Pearson test at P<0.05. Results showed that animals scored as ‘3’ in FQS had a lower hematocrit and a higher FEC (p<0.05) than animals scored as ‘1’ (hematocrit: 26, 24, 23 and FEC 2107, 2962, 4626 respectively for 1, 2 and 3 FQS). There were correlations between FQS and FEC (r = 0.16), FQS and hematocrit (r = -0.33) an FQS and weight gain (r = -0.20) indicating that worst FQS animals (score 3) had greater gastrointestinal parasites’ infection, were more anemic and had lower weight gain than animals scored as ‘1’ or ‘2’ for FQS. Concerning the lamb´s age, animals that received score ‘3’ in FQS, maintained gastrointestinal parasites’ infection over the time (P<0.05). It was concluded that FQS could be an important indicator to be included in the selective treatment for control verminosis in lambs.

Keywords: fleece, gastrointestinal parasites, sheep, welfare

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Authors: Asif Arshid, Ying Huang, Denver Tolliver

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Finite Element (FE) method coupled with ever-increasing computational powers has substantially advanced the reliability of deterministic three dimensional structural analyses of a structure with uniform material properties. However, railways trackbed is made up of diverse group of materials including steel, wood, rock and soil, while each material has its own varying levels of heterogeneity and imperfections. It is observed that the application of probabilistic methods for trackbed structural analysis while incorporating the material and geometric variabilities is deeply underworked. The authors developed and validated a 3-dimensional FE based numerical trackbed model and in this study, they investigated the influence of variability in Young modulus and thicknesses of granular layers (Ballast and Subgrade) on the reliability index (-index) of the subgrade layer. The influence of these factors is accounted for by changing their Coefficients of Variance (COV) while keeping their means constant. These variations are formulated using Gaussian Normal distribution. Two failure mechanisms in subgrade namely Progressive Shear Failure and Excessive Plastic Deformation are examined. Preliminary results of risk-based probabilistic analysis for Progressive Shear Failure revealed that the variations in Ballast depth are the most influential factor for vertical stress at the top of subgrade surface. Whereas, in case of Excessive Plastic Deformations in subgrade layer, the variations in its own depth and Young modulus proved to be most important while ballast properties remained almost indifferent. For both these failure moods, it is also observed that the reliability index for subgrade failure increases with the increase in COV of ballast depth and subgrade Young modulus. The findings of this work is of particular significance in studying the combined effect of construction imperfections and variations in ground conditions on the structural performance of railroad trackbed and evaluating the associated risk involved. In addition, it also provides an additional tool to supplement the deterministic analysis procedures and decision making for railroad maintenance.

Keywords: finite element analysis, numerical modeling, probabilistic methods, risk and reliability analysis, subgrade

Procedia PDF Downloads 139

Authors: Maryam Amiri Resketi, Sakineh Yeganeh, Khosro Jani Khalili

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The aim of this study was to investigate the effect of dietary lemon peel essential oil (Citrus limon) on serum parameters and liver enzyme activity of rainbow trout (Oncorhynchus mykiss) was exposed to deltamethrin. The 96-hour lethal concentrations of the toxin on rainbow trout (Oncorhynchus mykiss), was determined according to standard procedures O.E.C.D in static (Static). 96-hour LC50 was obtained 0.0082 mg/l by using statistical methods Probit program version. The maximum allowable concentration of deltamethrin was calculated 0.00082 mg/l in natural environment and was used for this experiment. Eight treatments were designed based on 3 levels of lemon essential oil 200, 400 and 600 mg/kg and 2 levels of deltamethrin 0 and 0.00082. Rainbow trout with an average weight of 95.14 ± 3.8 g were distributed in 300-liter tanks and cultured for eight weeks. Fish were fed in an amount of 2% of body weight. Water changes were done on a daily basis (90 percent of the tank). About the tanks containing 10 % deltamethrin, after dewatering, suitable concentration of toxin was added to water. At the end of the test, serum biochemical parameters (total protein, albumin, glucose, cholesterol, and triglycerides) and liver enzymes (ALP, AST, ALT and LDH) were evaluated. In treatments without and with toxin, increasing 400 mg/kg oil increased total protein and albumin levels and lower cholesterol and triglycerides were observed (p < 0.05). Rise to the level of 400 mg/kg of lemon peel essential oil treatments contain pesticides, reduced the amount of enzymes ALP, ALT and LDH compared to treatment of toxin-free lemon peel essential oil (p < 0.05). The results showed that usage of lemon peel essential oil in fish diet can increase the immune system parameters and strengthen it with strong antioxidant activity followed by reducing the effect of deltamethrin on the immune system of fish and effective dose can prevent the adverse effects of toxin due to the weakening of the fish immune system at the time of toxic pollutant entrance in fish farms.

Keywords: deltamethrin, Oncorhynchus mykiss, LC5096h, lemon peel (citrus limon) essential oil, serum parameters, liver enzymes

Procedia PDF Downloads 201

Authors: Nicole Scott, Emily Dwyer, Cara Patrissy, Samantha Bonventre, Lina Begdache

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Across North America, the use and abuse of Attention Deficit Hyperactivity Disorder (ADHD) medication, cannabis, nicotine, and other psychoactive substances across college campuses have become an increasingly prevalent problem. Students frequently use these substances to aid their studying or deal with their mental health issues. However, it is still unknown what psychoactive substances are likely to be abused when college students illicitly use ADHD medication. In addition, it is not clear which psychoactive substance is associated with mental distress. Thus, the purpose of this study is to fill these gaps by assessing the use of different psychoactive substances when illicit ADHD medication is used; and how this association relates to mental stress. A total of 702 undergraduate students from different college campuses in the U.S. completed an anonymous survey distributed online. Data were self-reported on demographics, the use of ADHD medications, cannabis, nicotine, other psychoactive drugs, and mental distress, and feelings and opinions on the use of illicit study drugs were all included in the survey. Mental distress was assessed using the Kessler Psychological Distress 6 Scale. Data were analyzed in SPSS, Version 25.0, using Pearson’s Correlation Coefficient. Our results show that use of ADHD medication, cannabis use (non-frequent and very frequent), and nicotine use (non-frequent and very frequent), there were both statistically significant positive and negative correlations to specific psychoactive substances and their corresponding frequencies. Along the same lines, ADHD medication, cannabis use (non-frequent and very frequent), and nicotine use (non-frequent and very frequent) had statistically significant positive and negative correlations to specific mental distress experiences. As these findings are combined, a vicious loop can initiate a cycle where individuals who abuse psychoactive substances may or may not be inclined to use other psychoactive substances. This may later inhibit brain functions in those main areas of the brain stem, amygdala, and prefrontal cortex where this vicious cycle may or may not impact their mental distress. Addressing the impact of study drug abuse and its potential to be associated with further substance abuse may provide an educational framework and support proactive approaches to promote awareness among college students.

Keywords: stimulant, depressant, nicotine, ADHD medication, psychoactive substances, mental health, illicit, ecstasy, adrenochrome

Procedia PDF Downloads 63

Authors: Kirstin Griffin

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During a period of increased anxiety and stress, communication became the essential tool to help the public stay informed and feel prepared during the Covid-19 pandemic. However, certain groups of patients were not feeling as reassured. The news and media blasted the message that patients with diabetes were “high-risk" in regards to contracting the Covid-19 infection. Routine clinics were being cancelled, GP practices were closing their doors, and patients with type 1 diabetes were understandably scared. The influx of calls to diabetes specialists nurses from concerned patients highlighted the need for better and more specialised information. An Application specifically for patients with type 1 diabetes was created to deliver this information, and it proved to be the essential communication tool that was desperately needed. The Application for patients with type 1 diabetes aimed to deliver specialist information to patients in regards to their diagnosis, management, and ongoing follow-up commitments. The Application gives practical advice on multiple areas of diabetes management, including sick-day rules and diabetic emergencies, as well as up-to-date information on technology, including setting up Libre devices and downloading glucose meters to facilitate attending virtual clinics. Delivery of this information in an easy-to-understand and comprehensive way is intended to improve patient engagement with diabetes services and ultimately empower patients in the control of their own disease. The application also offers a messaging service to allow the diabetes team to send out alerts to patient groups on specific issues, such as changes to clinics, or respond to recent news updates regarding Covid-19. The App was launched in NHS Fife in June 2020 and has amassed 800 active users so far. There is growing engagement with the App since its launch, with over 1000 user interactions in the last month alone. Feedback shows that 100% of users like the App and have found it useful in the management of their diabetes. The App has proven to be an essential tool in communication with one of the most vulnerable groups during the Covid-19 pandemic, and its ongoing development will continue to increase patient engagement and improve glycaemic control for patients with type 1 diabetes. The future of chronic disease management should involve digital solutions such as apps to further empower patients in their healthcare.

Keywords: diabetes, endocrinology, digital healthcare, medical apps

Procedia PDF Downloads 87

Authors: Rima T. Alfaraj, Murtadha J. Al Tammar, Khaqan Khan, Khalid M. Alruwaili

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OBJECTIVE/SCOPE (25-75): Caliper logging data provides critical information about wellbore shape and deformations, such as stress-induced borehole breakouts or washouts. Multiarm mechanical caliper logs are often run using wireline, which can be time-consuming, costly, and/or challenging to run in certain formations. To minimize rig time and improve operational safety, it is valuable to develop analytical solutions that can estimate caliper logs using available Logging-While-Drilling (LWD) data without the need to run wireline caliper logs. As a first step, the objective of this paper is to perform statistical analysis using an extensive datasetto identify important physical parameters that should be considered in developing such analytical solutions. METHODS, PROCEDURES, PROCESS (75-100): Caliper logs and LWD data of eleven wells, with a total of more than 80,000 data points, were obtained and imported into a data analytics software for analysis. Several parameters were selected to test the relationship of the parameters with the measured maximum and minimum caliper logs. These parameters includegamma ray, porosity, shear, and compressional sonic velocities, bulk densities, and azimuthal density. The data of the eleven wells were first visualized and cleaned.Using the analytics software, several analyses were then preformed, including the computation of Pearson’s correlation coefficients to show the statistical relationship between the selected parameters and the caliper logs. RESULTS, OBSERVATIONS, CONCLUSIONS (100-200): The results of this statistical analysis showed that some parameters show good correlation to the caliper log data. For instance, the bulk density and azimuthal directional densities showedPearson’s correlation coefficients in the range of 0.39 and 0.57, which wererelatively high when comparedto the correlation coefficients of caliper data with other parameters. Other parameters such as porosity exhibited extremely low correlation coefficients to the caliper data. Various crossplots and visualizations of the data were also demonstrated to gain further insights from the field data. NOVEL/ADDITIVE INFORMATION (25-75): This study offers a unique and novel look into the relative importance and correlation between different LWD measurements and wireline caliper logs via an extensive dataset. The results pave the way for a more informed development of new analytical solutions for estimating the size and shape of the wellbore in real-time while drilling using LWD data.

Keywords: LWD measurements, caliper log, correlations, analysis

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Authors: M. Bolacali

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The aim of the study is to determine the effect of immunocastration vaccine administration at different doses on fattening performance of feedlot Holstein bulls. Bopriva® is a vaccine that stimulates the animals' own immune system to produce specific antibodies against gonadotropin releasing factor (GnRF). Ninety four Holstein male calves (309.5 ± 2.58 kg body live weight and 267 d-old) assigned to the 4 treatments. Control group; 1 mL of 0.9% saline solution was subcutaneously injected to intact bulls on 1st and 60th days of the feedlot as placebo. On the same days of the feedlot, Bopriva® at two doses of 1 mL and 1 mL for Trial-1 group, 1.5 mL, and 1.5 mL for Trial-2 group, 1.5 mL, and 1 mL for Trial-3 group were subcutaneously injected to bulls. The study was conducted in a private establishment in the Sirvan district of Siirt province and lasted 180 days. The animals were weighed at the beginning of fattening and at 30-day intervals to determine their live weights at various periods. The statistical analysis for normal distribution data of the treatment groups was carried out with the general linear model procedure of SPSS software. The fattening initial live weight in Control, Trial-1, Trial-2 and Trial-3 groups was respectively 309.21, 306.62, 312.11, and 315.39 kg. The fattening final live weight was respectively 560.88, 536.67, 548.56, and 548.25 kg. The daily live weight gain during the trial was respectively 1.40, 1.28, 1.31, and 1.29 kg/day. The cold carcass yield was respectively 51.59%, 50.32%, 50.85%, and 50.77%. Immunocastration vaccine administration at different doses did not affect the live weights and cold carcass yields of Holstein male calves reared under intensive conditions (P > 0.05). However, it was determined to reduce fattening performance between 61-120 days (P < 0.05) and 1-180 days (P < 0.01). In addition, it was determined that the best performance among the vaccine-treated groups occurred in the group administered a 1.5 mL of vaccine on the 1st and 60th study days. In animals, castration is used to control fertility, aggressive and sexual behaviors. As a result, the fact that stress is induced by physical castration in animals and active immunization against GnRF maintains performance by maximizing welfare in bulls improves carcass and meat quality and controls unwanted sexual and aggressive behavior. Considering such features, it may be suggested that immunocastration vaccine with Bopriva® can be administered as a 1.5 mL dose on the 1st and 60th days of the fattening period in Holstein bulls.

Keywords: anti-GnRF, fattening, growth, immunocastration

Procedia PDF Downloads 192

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

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Carotid artery stenting (CAS) is the standard procedure for patients with severe carotid stenosis at high risk for carotid endarterectomy (CAE). A major drawback of CAS is the higher incidence of procedure-related stroke compared with traditional open surgical treatment for carotid stenosis - CEA, even with the use of the embolic protection devices (EPD). As the currently available bare metal stents cannot address this problem, our research group 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 maintaining 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 atherosclerotic stenosis. The purpose of this study is to evaluate the effect of membrane coating on the stent flexibility in order to improve the clinical performance of our novel covered stents. A total of 21 stents were evaluated in this study: 15 self expanding bare nitinol stents and 6 PTFE-covered stents. 10 of the bare stents were coated with 11%, 16% and 22% Polyurethane(PU), 4%, 6.25% and 11% EE, as well as 22% PU plus 5 μm Parylene. Different laser cutting designs were performed on 4 of the PTFE covert stents. All the stents, with or without the covered membrane, were subjected to a three-point flexural test. The stents were placed on two supports that are 30 mm apart, and the actuator is applying a force in the exact middle of the two supports with a loading pin with radius 2.5 mm. The loading pin displacement change, the force and the variation in stent shape were recorded for analysis. The flexibility of the stents was evaluated by the lumen area preservation at three displacement bending levels: 5mm, 7mm, and 10mm. All the lumen areas in all stents decreased with the increase of the displacement from 0 to 10 mm. The bare stents were able to maintain 0.864 ± 0.015, 0.740 ± 0.025 and 0.597 ± 0.031of original lumen area at 5 mm, 7 mm and 10mm displacement respectively. For covered stents, the stents with EE coating membrane showed the best lumen area preservation (0.839 ± 0.005, 0.7334 ± 0.043 and 0.559 ± 0.014), whereas, the stents with PU and Parylene coating were only 0.662, 0.439 and 0.305. Bending stiffness was also calculated and compared. These results provided optimal material information and it was crucial for enhancing clinical performance of our novel covered stents.

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

Procedia PDF Downloads 295

Authors: Majid Afkhami, Maryam Ehsanpour, Reza Khoshnood, Zahra Khoshnood, Rastin Afkhami

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Marine pollution is a global environmental problem. Different human activities on land, in the water and in the air contribute to the contamination of seawater, sediments and organisms with potentially toxic substances. Contaminants can be natural substances or artificially produced compounds. After discharge into the sea, contaminants can stay in the water in dissolved form or they can be removed from the water column through sedimentation to the bottom sediments. Histopathological alterations can be used as indicators for the effects of various anthropogenic pollutants on organisms and are a reflection of the overall health of the entire population in the ecosystem. These histo pathological biomarkers are closely related to other biomarkers of stress since many pollutants have to undergo metabolic activation in order to be able to provoke cellular change in the affected organism. In order to make evaluation of the effects of oil pollution, some heavy metals bioaccumulation and explore their histopathological effects on hepatocytes of Oriental sole (Euryglossa orientalis) and Deep flounder (Psettodes erumei), fishes caught from two areas of north coast of the Persian Gulf: Bandar Abbass and Bandar Lengeh. Concentrations of Ni and V in liver of both species in two sampling regions were in following order: Bandar abbass Bandar lengeh; also between two species, these quantities were higher in P. erumei than E. orientalis in both sampling regions. Histopathology of the liver shows some cellular alterations including: degeneration, necrosis and tissue disruption, and histopathological effects were severe in P. erumei than E. orientalis. Results showed that Bandar Abbass region was more polluted than Bandar Lengeh, and because Ni and V were oil pollution indicators, and two flat fishes were benthic, they can receive considerable amount of oil pollution through their biological activities like feeding. Also higher amounts of heavy metal concentrations and major histopathological effects in E. orientalis showed strong relationship between benthic habitat of the fish and amounts of received pollutants from water and sediments, because E. orientalis is more related to the bottom than P. erumei.

Keywords: heavy metals, flatfishes, Persian Gulf, oil pollution

Procedia PDF Downloads 343

Authors: Christian Louis Kühner, Florian Pfeffel, Valentin Nickolai

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Taking care of children, dependents, or pets can be a difficult and time-consuming task. Especially for part- and full-time employees, it can feel exhausting and overwhelming to meet these obligations besides working a job. Thus, working mostly at home and not having to drive to the company can save valuable time and stress. This study aims to show the influence that the working model has on the job satisfaction of employees with care responsibilities in comparison to employees who do not have such obligations. Using structural equation modeling (SEM), the three work models, “work from home”, “working remotely”, and a hybrid model, have been analyzed based on 13 influencing constructs on job satisfaction. These 13 factors have been further summarized into three groups “classic influencing factors”, “influencing factors changed by remote working”, and “new remote working influencing factors”. Based on the influencing factors on job satisfaction, an online survey was conducted with n = 684 employees from the service sector. Here, Cronbach’s alpha of the individual constructs was shown to be suitable. Furthermore, the construct validity of the constructs was confirmed by face validity, content validity, convergent validity (AVE > 0.5: CR > 0.7), and discriminant validity. In addition, confirmatory factor analysis (CFA) confirmed the model fit for the investigated sample (CMIN/DF: 2.567; CFI: 0.927; RMSEA: 0.048). The SEM-analysis has shown that the most significant influencing factor on job satisfaction is “identification with the work” with β = 0.540, followed by “Appreciation” (β = 0.151), “Compensation” (β = 0.124), “Work-Life-Balance” (β = 0.116), and “Communication and Exchange of Information” (β = 0.105). While the significance of each factor can vary depending on the work model, the SEM-analysis shows that the identification with the work is the most significant factor in all three work models and, in the case of the traditional office work model, it is the only significant influencing factor. The study shows that among the employees with care responsibilities, the higher the proportion of working from home in comparison to working from the office, the more satisfied the employees are with their job. Since the work models that meet the requirements of comprehensive care led to higher job satisfaction amongst employees with such obligations, adapting as a company to such private obligations by employees can be crucial to sustained success. Conversely, the satisfaction level of the working model where employees work at the office is higher for workers without caregiving responsibilities.

Keywords: care responsibilities, home office, job satisfaction, structural equation modeling

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Authors: F. Elhaouzi, H. Lahlali, M. Zaghrioui, I. El Aboudi A. BelfKira, A. Mdarhri

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The effect of physico chemical properties of solvents on the transport process and mechanical properties in elastomeric nano composite materials is reported. The investigated samples are formed by a semi-crystalline ethylene-co-butyl acrylate polymer filled with hard spherical carbon black (CB) nano particles. The swelling behavior was studied by immersion the dried samples in selected solvents at room temperature during 2 days. For this purpose, two chemical compounds methyl derivatives of aromatic hydrocarbons of benzene, i.e. toluene and xylene, are used to search for the mass and molar volume dependence on the absorption kinetics. Mass gain relative to the mass of dry material at specific times was recorded to probe the absorption kinetics. The transport of solvent molecules in these filled elastomeric composites is following a Fickian diffusion mechanism. Additionally, the swelling ratio and diffusivity coefficient deduced from the Fickian law are found to decrease with the CB concentration. These results indicate that the CB nano particles increase the effective path length for diffusion and consequently limit the absorption of the solvent by occupation free volumes in the material. According to physico chemical properties of the two used solvents, it is found that the diffusion is more important for the toluene molecules solvent due to their low values of the molecular weight and volume molar compared to those for the xylene. Differential Scanning Calorimetry (DSC) and X-ray photo electron (XPS) were also used to probe the eventual change in the chemical composition for the swollen samples. Mechanically speaking, the stress-strain curves of uniaxial tensile tests pre- and post- swelling highlight a remarkably decrease of the strength and elongation at break of the swollen samples. This behavior can be attributed to the decrease of the load transfer density between the matrix and the CB in the presence of the solvent. We believe that the results reported in this experimental investigation can be useful for some demanding applications e.g. tires, sealing rubber.

Keywords: nanocomposite, absorption kinetics, mechanical behavior, diffusion, modelling, XPS, DSC

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Authors: Georgios P. Georgiou

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Infants are able to discriminate a number of sound contrasts in most languages. However, this ability is not available in adults who might face difficulties in discriminating accurately second language sound contrasts as they filter second language speech through the phonological categories of their native language. For example, Spanish speakers often struggle to perceive the difference between the English /ε/ and /æ/ because both vowels do not exist in their native language; so they assimilate these vowels to the closest phonological category of their first language. The present study aims to uncover the perceptual patterns of Arabic adult speakers in regard to the vowels of their second language (Greek). Still, there is not any study that investigates the perception of Greek vowels by Arabic speakers and, thus, the present study would contribute to the enrichment of the literature with cross-linguistic research in new languages. To the purpose of the present study, 15 native speakers of Egyptian Arabic who permanently live in Cyprus and have adequate knowledge of Greek as a second language passed through vowel assimilation and vowel contrast discrimination tests (AXB) in their second language. The perceptual stimuli included non-sense words that contained vowels in both stressed and unstressed positions. The second language listeners’ patterns were analyzed through the Perceptual Assimilation Model which makes testable hypotheses about the assimilation of second language sounds to the speakers’ native phonological categories and the discrimination accuracy over second language sound contrasts. The results indicated that second language listeners assimilated pairs of Greek vowels in a single phonological category of their native language resulting in a Category Goodness difference assimilation type for the Greek stressed /i/-/e/ and the Greek stressed-unstressed /o/-/u/ vowel contrasts. On the contrary, the members of the Greek unstressed /i/-/e/ vowel contrast were assimilated to two different categories resulting in a Two Category assimilation type. Furthermore, they could discriminate the Greek stressed /i/-/e/ and the Greek stressed-unstressed /o/-/u/ contrasts only in a moderate degree while the Greek unstressed /i/-/e/ contrast could be discriminated in an excellent degree. Two main implications emerge from the results. First, there is a strong influence of the listeners’ native language on the perception of the second language vowels. In Egyptian Arabic, contiguous vowel categories such as [i]-[e] and [u]-[o] do not have phonemic difference but they are subject to allophonic variation; by contrast, the vowel contrasts /i/-/e/ and /o/-/u/ are phonemic in Greek. Second, the role of stress is significant for second language perception since stressed vs. unstressed vowel contrasts were perceived in a different manner by the Greek listeners.

Keywords: Arabic, bilingual, Greek, vowel perception

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Authors: Manuela Caciula, Luis Torres, Simion Tomoiaga

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Introduction: The SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), more commonly referred to as COVID-19, has wreaked havoc on all facets of higher education since its inception in late 2019. College students, in particular, significantly reduced their daily energy expenditure and increased the time spent sitting to listen to online classes and complete their studies from home. This change, in combination with the associated COVID-19 lockdown, presumably decreased physical activity levels, increased mental health symptoms, and led to the promotion of unhealthy eating habits. Objectives: The main objective of this study was to determine the current self-reported physical activity levels, mental health symptoms, and body composition of college students after the COVID-19 lockdown in order to develop future interventions for the overall improvement of health. Methods: All participants completed pre-existing, well-validated surveys for both physical activity (International Physical Activity Questionnaire - long form) and mental health (Hospital Anxiety and Depression Scale). Body composition was assessed in person with the use of an Inbody 570 device. Results: Of the 90 American college students (M age = 22.52 ± 4.54, 50 females) who participated in this study, depressive and anxious symptom scores consistent with 58% (N = 52) heightened symptomatology, 17% (N = 15) moderate borderline symptomatology, and 25% (N = 23) asymptomatology were reported. In regard to physical activity, 79% (N = 71) of the students were highly physically active, 18% (N = 16) were moderately active, and 3% (N = 3) reported low levels of physical activity. Additionally, 46% (N = 41) of the students maintained an unhealthy body fat percentage based on World Health Organization recommendations. Strong, significant relationships were found between anxiety and depression symptomatology and body fat percentage (P = .003) and skeletal muscle mass (P = .015), with said symptomatology increasing with added body fat and decreasing with added skeletal muscle mass. Conclusions: Future health interventions for American college students should be focused on strategies to reduce stress, anxiety, and depressive characteristics, as well as nutritional information on healthy eating, regardless of self-reported physical activity levels.

Keywords: physical activity, mental health, body composition, COVID-19

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Authors: Marianne Simons, Sinan Kurt, Marjolein Stefens, Kai Karos, Johan Lataster

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As cultural diversity within older populations in European countries increases, the role of cultural background should be taken account of in aging studies. Bonding social capital (BSC), containing someone’s socio-emotional resources, is recognised as an important ingredient for wellbeing in old age and found to be associated with someone’s cultural background. The current study examined the association between BSC, loneliness and wellbeing in a sample including older Turkish migrants with a collectivistic cultural background and native Dutch older adults, both living in the Netherlands, characterised by an individualistic culture. A sample of 119 Turkish migrants (64.7% male; age 65-87, M(SD)=71.13(5.04) and 124 native Dutch adults (32.3% male, age 65-94, M(SD)= 71.9(5.32) filled out either an online or printed questionnaire measuring BSC, psychological, social and emotional well-being, loneliness and relevant demographic covariates. Regression analysis - including confounders age, gender, level of education, physical health and relationship - showed positive associations between BSC and respectively emotional, social and psychological well-being and a negative association with loneliness in both samples. Moderation analyses showed that these associations were significantly stronger for the Turkish older migrants than for their native peers. Measurement invariance analysis indicated partial metric invariance for the measurement of BSC and loneliness and non-invariance for wellbeing, calling for caution comparing means between samples. The results stress the importance of BSC for wellbeing of older migrants from collectivistic cultures living in individualistic countries. Previous research, shows a trend of older migrants displaying lower levels of BSC as well as associated variables, such as education, physical health, and financial income. This calls for more research of the interplay between demographic and psychosocial factors restraining mental wellbeing of older migrant populations. Measurement invariance analyses further emphasize the importance of taking cultural background into account in positive aging studies.

Keywords: positive aging, cultural background, wellbeing, social capital, loneliness

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Authors: Jaan-Willem Simon, Bertram Stier, Brett Bednarcyk, Evan Pineda, Stefanie Reese

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Textile composites, in which the reinforcing fibers are woven or braided, have become very popular in numerous applications in aerospace, automotive, and maritime industry. These textile composites are advantageous due to their ease of manufacture, damage tolerance, and relatively low cost. However, physics-based modeling of the mechanical behavior of textile composites is challenging. Compared to their unidirectional counterparts, textile composites introduce additional geometric complexities, which cause significant local stress and strain concentrations. Since these internal concentrations are primary drivers of nonlinearity, damage, and failure within textile composites, they must be taken into account in order for the models to be predictive. The macro-scale approach to modeling textile-reinforced composites treats the whole composite as an effective, homogenized material. This approach is very computationally efficient, but it cannot be considered predictive beyond the elastic regime because the complex microstructural geometry is not considered. Further, this approach can, at best, offer a phenomenological treatment of nonlinear deformation and failure. In contrast, the mesoscale approach to modeling textile composites explicitly considers the internal geometry of the reinforcing tows, and thus, their interaction, and the effects of their curved paths can be modeled. The tows are treated as effective (homogenized) materials, requiring the use of anisotropic material models to capture their behavior. Finally, the micro-scale approach goes one level lower, modeling the individual filaments that constitute the tows. This paper will compare meso- and micro-scale approaches to modeling the deformation, damage, and failure of textile-reinforced polymer matrix composites. For the mesoscale approach, the woven composite architecture will be modeled using the finite element method, and an anisotropic damage model for the tows will be employed to capture the local nonlinear behavior. For the micro-scale, two different models will be used, the one being based on the finite element method, whereas the other one makes use of an embedded semi-analytical approach. The goal will be the comparison and evaluation of these approaches to modeling textile-reinforced composites in terms of accuracy, efficiency, and utility.

Keywords: multiscale modeling, continuum damage model, damage interaction, textile composites

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Authors: Wai Sang Wu, Florence Pik Sze Mok

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Introduction: Ageing population is one of the hot topics nowadays in the world and this phenomenon is believed to exacerbate continuously in the future. According to the latest information from World Health Organization (WHO) in 2016, the proportion of people aged more than 60 years is projected to be doubled from 12% in 2015 to 22% in 2050 of the world's population. Similarly, according to figures released by the Census and Statistic Department of Hong Kong in 2015, the contribution of elderly aged more than 65 years olds is projected to increase from 15% in 2014 to 34% in 2064 in local community. On the other hand, falls in elderly is a common problem, and it can bring along many negative consequences among elders, such as reducing their mobility level as well as their quality of life. In addition, it can also increase the caring stress of their family caregivers and as well increase the reliance and burden on the medical care system of Hong Kong. Therefore, appropriate measures should be implemented in order to minimize the risk of fall among elders. The objective of this study is to evaluate the effectiveness of the chair-based exercise programme in affecting the balance of the elderly in Hong Kong. Methods: Thirteen healthy subjects (males = 2; females = 11; mean age: 76.2 ± 7.8 years old) were recruited from an elderly social centre in the community to participate in a structural chair-based exercise programme for 6 weeks (1 session per week; 60-minutes per session). Subjects were being assessed on their balance ability using three commonly used clinical assessments, namely, 1) single leg stance (SLS) test, 2) functional reach test, and 3) 360-degree turn test, before and after their participation in the chair-based exercise programme. Pre and post within-subject comparison was adopted to assess the effectiveness of the programme. Results: There was significant improvement (p < 0.05) in all balance parameters of the subjects after their participation in the exercise programme. Elderly demonstrated significant improvement in SLS (p < 0.012), functional reach (p < 0.030) and 360 degree turn (p < 0.043). Conclusions: This study showed that a community chair-based exercise programme is effective in improving the balance ability of the elders. It seems to be another exercise regime that should be promoted among the elders in order to minimize their risk of falls and its negative consequence.

Keywords: balance, chair-based exercise programme, community, elderly

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Authors: Mahabub Alam, Mohammad Mahmudul Hassan, M. Hasanuzzaman, M. Ahasanul Hoque

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Animals are transported from one place to another for different purposes in Bangladesh. However, the potential effect of long-distance transport on cattle health has not frequently been studied. Therefore, this study was conducted to assess health conditions of cattle transported from a long distance to Chittagong in Bangladesh. A total of 100 adult cattle, regardless of breed and sex, were selected at Benapole live cattle market in Jessore between August and September 2015 for the study. Blood samples were taken from 50 randomly selected cattle at 0 hours before transportation, just after transportation, at 12-16 hours post-conclusion of transportation, and 24 hours after transportation. The external health conditions and injuries of the cattle were assessed by close inspection, and the trader was interviewed using the structured questionnaire. Images of cattle injuries were taken with a camera. The basic internal health of the cattle was evaluated using standard hemato-biochemical tests. Animals were fasted and remained standing within a small space allocation (8-10 sq feet/animal) in the vehicle during transportation. Animals were provided only with paddy straw and water prior to selling at the destination market. The overall frequency of cattle injuries varied significantly (26% before vs. 47% after transportation; p < 0.001). The frequency of different cattle injuries also significantly varied by types such as abrasion (11% vs. 21%; p < 0.05) and barbed wire injury (9% vs. 18%; p < 0.05). Single cattle injury differed significantly (21% vs. 36%; p < 0.001). Cattle health conditions varied significantly (nasal discharge: 15% vs. 28%; p < 0.05; diarrhea: 15% vs. 23%; p < 0.05 and severe dehydration: 8% vs. 20%; p < 0.001). The values of hemoglobin (Hb), total erythrocyte count (TEC), total leukocyte count (TLC), lymphocyte (L), neutrophil (N) and eosinophil (E) varied significantly (p ≤ 0.01) (Hb: 11.1mg/dl vs. 12.3mg/dl; TEC: 4.7 million/ml vs. 5.7million/ml; TLC: 6.2 thousand/ml vs. 7.3 thousand/ml; L: 61.7% vs. 58.1%; N: 29.7% vs. 32.8%; E: 3.8% vs. 4.7%). The values of serum total protein (TP), creatine kinase (CK), triglyceride (TG), calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) significantly differed (p ≤ 0.05) (TP: 6.8g/dl vs. 8.2g/dl; CK:574.9u/l vs. 1288u/l; TG: 104.7mg/dl vs. 127.7mg/dl; Ca: 11.3mg/dl vs. 13mg/dl; P: 7.3mg/dl vs. 7.6mg/dl; ALP: 303u/l vs. 363u/l). The identified status of external and internal health conditions of the cattle for trading purpose due to long-distance transportation in the present study indicates a high degree of transport stress and poor animal welfare.

Keywords: animal welfare, cattle, external and internal health conditions, transportation

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Authors: Vichayada Laohapiboolkul

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Introduction: As the legal use of cannabis is being widely accepted throughout the world, medical cannabis has been explored in order to become an alternative cure for patients. Tetrahydrocannabinol (THC) and Cannabidiol (CBD) are natural cannabinoids found in the Cannabis plant which is proved to have positive treatment for various diseases and symptoms such as chronic pain, neuropathic pain, spasticity resulting from multiple sclerosis, reduce cancer-associated pain, autism spectrum disorders (ASD), dementia, cannabis and opioid dependence, psychoses/schizophrenia, general social anxiety, posttraumatic stress disorder, anorexia nervosa, attention-deficit hyperactivity disorder, and Tourette's disorder. Regardless of all the medical benefits, THC, if not metabolized, can lead to mild up to severe adverse drug reactions (ADR). The enzyme CYP2C19 was found to be one of the metabolizers of THC. However, the suballele CYP2C19*2 manifests as a poor metabolizer which could lead to higher levels of THC than usual, possibly leading to various ADRs. Objective: The aim of this study was to investigate the distribution of CYP2C19, specifically CYP2C19*2, genes in Thai patients treated with medical cannabis along with adverse drug reactions. Materials and Methods: Clinical data and EDTA whole blood for DNA extraction and genotyping were collected from patients for this study. CYP2C19*2 (681G>A, rs4244285) genotyping was conducted using the Real-time PCR (ABI, Foster City, CA, USA). Results: There were 42 medical cannabis-induced ADRs cases and 18 medical cannabis tolerance controls who were included in this study. A total of 60 patients were observed where 38 (63.3%) patients were female and 22 (36.7%) were male, with a range of age approximately 19 - 87 years. The most apparent ADRs for medical cannabis treatment were dry mouth/dry throat (76.7%), followed by tachycardia (70%), nausea (30%) and a few arrhythmias (10%). In the total of 27 cases, we found a frequency of 18 CYP2C19*1/*1 alleles (normal metabolizers, 66.7%), 8 CYP2C19*1/*2 alleles (intermediate metabolizers, 29.6%) and 1 CYP2C19*2/*2 alleles (poor metabolizers, 3.7%). Meanwhile, 63.6% of CYP2C19*1/*1, 36.3% and 0% of CYP2C19*1/*2 and *2/*2 in the tolerance controls group, respectively. Conclusions: This is the first study to confirm the distribution of CYP2C19*2 allele and the prevalence of poor metabolizer genes in Thai patients who received medical cannabis for treatment. Thus, CYP2C19 allele might serve as a pharmacogenetics marker for screening before initiating treatment.

Keywords: medical cannabis, adverse drug reactions, CYP2C19, tetrahydrocannabinol, poor metabolizer

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Authors: Lorenza Fabiocchi, Marco Mariani, Andrea Lucchini Huspek, Matteo Pozzi, Massimiliano Bestetti, Serena Graziosi, Nora Lecis

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Additive manufacturing of stainless steels is rapidly developing thanks to the ability to achieve complex designs effortlessly. Stainless steel 17-4PH is valued for its high strength and corrosion resistance, however intricate geometries are challenging to obtain due to rapid tool wear when machined. Binder jetting additive manufacturing was used to produce 17–4PH samples and pulsed electron beam surface treatment was investigated to enhance surface properties of components. The aim is to improve the tribological performance compared to the as-sintered condition and the H900 aging process, which optimizes hardness and wear resistance. Printed samples were sintered in a reducing atmosphere and superficially treated with an electron beam by varying the voltage (20 - 25 - 30 kV) and pulse count (20 – 40 pulses). Then, the surface was characterized from a microstructural and mechanical standpoint. Scratch tests were performed, and a reciprocating linear pin-on-disk wear test was conducted at 2 N and 10 Hz. Results showed that the voltage affects the roughness and thickness of the treated layer, whilst the number of pulses influences the hardening of the microstructure and consequently the wear resistance. Treated samples exhibited lower coefficients of friction compared to as-printed surfaces, though the values approached those of aged samples after the abrasion of the melted layer, indicating a deeper heat-affected zone formation. Different amounts of residual stress in the heat effected zone were individuated through the scratch tests. Still, the friction remained lower than that of as-printed specimens. This study demonstrates that optimizing electron beam parameters is vital for achieving surface performance comparable to bulk aging treatments, with significant implications for long-term wear resistance.

Keywords: low energy high current pulsed electron beam, tribology, binder jetting 3D printing, 17-4PH stainless steel

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Authors: Gulsharat A. Baigonakova, Ekaterina S. Marchenko, Venera R. Luchsheva

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The preferred materials for bone grafting are titanium-nickel alloys. They have a porous, permeable structure similar to that of bone tissue, can withstand long-term physiological stress in the body, and retain the scaffolding function for bone tissue ingrowth. Despite the excellent functional properties of these alloys, there is a possibility of post-operative infectious complications that prevent the newly formed bone tissue from filling the spaces created in a timely manner and prolong the rehabilitation period of patients. In order to minimise such consequences, it is necessary to use biocompatible materials capable of simultaneously fulfilling the function of a long-term functioning implant and an osteoreplacement carrier saturated with drugs. Methods to modify the surface by saturation with bioactive substances, in particular macrocyclic compounds, for the controlled release of drugs, biologically active substances, and cells are becoming increasingly important. This work is dedicated to the functionalisation of the surface of porous titanium nickelide by the deposition of macrocyclic compounds in order to provide titanium nickelide with antibacterial activity and accelerated osteogenesis. The paper evaluates the effect of macrocyclic compound deposition methods on the continuity, structure, and cytocompatibility of the surface properties of porous titanium nickelide. Macrocyclic compounds were deposited on the porous surface of titanium nickelide under the influence of various physical effects. Structural research methods have allowed the evaluation of the surface morphology of titanium nickelide and the nature of the distribution of these compounds. The method of surface functionalisation of titanium nickelide influences the size of the deposited bioactive molecules and the nature of their distribution. The surface functionalisation method developed has enabled titanium nickelide to be deposited uniformly on the inner and outer surfaces of the pores, which will subsequently enable the material to be uniformly saturated with various drugs, including antibiotics and inhibitors. The surface-modified porous titanium nickelide showed high biocompatibility and low cytotoxicity in in vitro studies. The research was carried out with financial support from the Russian Science Foundation under Grant No. 22-72-10037.

Keywords: biocompatibility, NiTi, surface, porous structure

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Authors: Mustapha Kamel Mihoubi, Essadik Kerkar, Abdelhamid Hebbouche

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According to the randomness of most of the factors affecting the stability of a gravity dam, probability theory is generally used to TESTING the risk of failure and there is a confusing logical transition from the state of stability failed state, so the stability failure process is considered as a probable event. The control of risk of product failures is of capital importance for the control from a cross analysis of the gravity of the consequences and effects of the probability of occurrence of identified major accidents and can incur a significant risk to the concrete dam structures. Probabilistic risk analysis models are used to provide a better understanding the reliability and structural failure of the works, including when calculating stability of large structures to a major risk in the event of an accident or breakdown. This work is interested in the study of the probability of failure of concrete dams through the application of the reliability analysis methods including the methods used in engineering. It is in our case of the use of level II methods via the study limit state. Hence, the probability of product failures is estimated by analytical methods of the type FORM (First Order Reliability Method), SORM (Second Order Reliability Method). By way of comparison, a second level III method was used which generates a full analysis of the problem and involving an integration of the probability density function of, random variables are extended to the field of security by using of the method of Mont-Carlo simulations. Taking into account the change in stress following load combinations: normal, exceptional and extreme the acting on the dam, calculation results obtained have provided acceptable failure probability values which largely corroborate the theory, in fact, the probability of failure tends to increase with increasing load intensities thus causing a significant decrease in strength, especially in the presence of combinations of unique and extreme loads. Shear forces then induce a shift threatens the reliability of the structure by intolerable values of the probability of product failures. Especially, in case THE increase of uplift in a hypothetical default of the drainage system.

Keywords: dam, failure, limit state, monte-carlo, reliability, probability, sliding, Taylor

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Authors: Abdullah Alassiri

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Prompted by the widespread saturation of Facebook usage in Saudi Arabia, among university students to socialize with online members, this study investigated the usage, self-presentation, psychological and sociological consequences of the Facebook social networking site among undergraduate students in Saudi Arabia. The problem statement of this study was addressed by answering the following questions: 1) What motivation do undergraduate students have for joining Facebook? 2) How do undergraduate students consume Facebook? 3) In what condition do undergraduate students need Facebook? 4) How do undergraduate students manage their self-presentation via Facebook? 5) What are the experiences obtained by the undergraduate students from Facebook psychologically? 6) What are the experiences obtained by the undergraduate students from Facebook sociologically? 7) How have Facebook activities affected the lifestyle of the undergraduate students?. These questions were answered by analyzing in-depth interview data collected from twenty male undergraduate students between the ages of 18 and 24 years selected from King Saud University (KSU) and King Khalid University (KKU) Saudi Arabia. Using thematic analysis, informants data were coded ‘R1 to R20’, validated and was transcribed to minimize error from translating into the study items from Arabic back to the English Language. Using purposive sampling method, informant perspective within the research context were explored. Data collection was confined to students’ motivations for engaging in online activities, self-presentation, psychological and sociological consequences to their everyday life was investigated based on the theoretical and philosophical perspective underpinnings media and gratification paradigm and social influence theory. The findings contributed to the development of important study themes that supported the development of a new research framework. Based on the analysis, all the study questions were answered. The findings of this study showed that the students use Facebook for the purpose of interacting with others, getting information and as knowledge sources. In terms of self-presentation, this study revealed that the students portray themselves in the real and not fake image while socializing with others. Psychological and sociological consequences from the usage of Facebook are recorded ranging from cheerful to stress and from loneliness to having many friends. As a conclusion, this study conclusively drew that Facebook is a very persuasive medium of communication among the University students in Saudi Arabia that bridges across socio-cultural boundaries and unite students to interact as a community.

Keywords: Saudi Arabia, Facebook, undergraduate students, social network

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Authors: Ivonne N. Pérez-Sánchez. María L. Rascón- Gasca, Angélica Riveros-Rosas, Rebeca Robles García

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Introduction: Primary caregivers of cancer patients have health problems related to their lack of time, stress, and fiscal strain. Their health problems could affect their patients’ health and also increase the expenses in public health. Aim: To describe self-care and risk behaviors in a sample of Mexican primary caregiver and the relation of these behaviors with emotional distress (caregiver burden, anxiety and depression symptoms), coping and sociodemographic variables. Method: Participated in this study 173 caregivers of a third level reference medical facility (age: M=49.4, SD=13.5) females 78%, males 22%, 57.5% were caregivers of patients with terminal cancer (CPTC), and 40.5% were caregivers of patients on oncology treatment (CPOT). Results: The 75.7% of caregivers reported to have had health problem in last six months as well as several symptoms which were related to emotional distress, these symptoms were more frequently between CPTC and female caregivers. A half (47.3%) of sample reported have had difficulties in caring their health; these difficulties were related to emotional distress and lower coping, more affected caregivers were who attend male patients and CPTC. The 76.8% of caregivers had health problems in last six months, but 26.5% of them waited to search medical care until they were very sick, and 11% didn't do it. Also, more than a half of sample (56.1%) admitted to have risk behaviors as drink alcohol, smoke or overeating for feeling well, these caregivers showed high emotional distress and lower coping. About caregivers healthy behaviors, 80% of them had a hobby; 27.2% do exercise usually and between 12% to 60% did medical checkups (glucose tests, blood pressure and cholesterol tests, eye exams and watched their weight), these caregivers had lower emotional distress and high coping, some variables related health behaviors were: care only one patient or a female patient and be a CPOT, social support, high educational level and experience as a caregiver in past. The half of caregivers were worrying to develop cancer in the future; this idea was 2.5 times more frequent in caregiver with problems to care their health. Conclusions: The results showed a big proportion of caregivers with medical problems. High emotional distress and low coping were related to physical symptoms, risk behaviors, and low self-care; poor self-care was frequently even in caregiver who have chronic illness.

Keywords: cancer, primary caregiver, risk behaviors, self-care

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Authors: Garima Singh, Kunal Malhotra

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Objective: The expansion of telehealth has been instrumental in increasing access to medical services, especially for underserved and rural communities. In 2020, 14 million patients received virtual care through telemedicine and the global telemedicine market is expected to reach up to $185 million by 2023. It provides a platform and allows a patient to receive primary care as well as specialized care using technology and the comfort of their homes. Telemedicine was particularly useful during COVID-pandemic and the number of telehealth visits increased by 5000% during that time. It continues to serve as a significant resource for patients seeking care and to bridge the gap between the disease and the treatment. Method: As per APA (American Psychiatric Association), Telemedicine is the process of providing health care from a distance through technology. It is a subset of telemedicine, and can involve providing a range of services, including evaluations, therapy, patient education and medication management. It can involve direct interaction between a physician and the patient. It also encompasses supporting primary care providers with specialist consultation and expertise. It can also involve recording medical information (images, videos, etc.) and sending this to a distant site for later review. Results: In our organization, we are using telepsychiatry and serving 25 counties and approximately 1.4 million people. We provide multiple services, including inpatient, outpatient, crisis intervention, Rehab facility, autism services, case management, community treatment and multiple other modalities. With project ECHO (Extension for Community Healthcare Outcomes) it has been used to advise and assist primary care providers in treating mental health. It empowers primary care providers to treat patients in their own community by sharing knowledge. Conclusion: Telemedicine has shown to be a great medium in meeting patients’ needs and accessible mental health. It has been shown to improve access to care in both urban and rural settings by bringing care to a patient and reducing barriers like transportation, financial stress and resources. Telemedicine is also helping with reducing ER visits, integrating primary care and improving the continuity of care and follow-up. There has been substantial evidence and research about its effectiveness and its usage.

Keywords: telehealth, telemedicine, access to care, medical technology

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Authors: Firas Daghistani, Hossam Abuel Naga

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Waste tyres is a global problem that has a negative effect on the environment, where there are approximately one billion waste tyres discarded worldwide yearly. Waste tyres are discarded in stockpiles, where they provide harm to the environment in many ways. Finding applications to these materials can help in reducing this global problem. One of these applications is recycling these waste materials and using them in geotechnical engineering. Recycled waste tyre particulates can be mixed with sand to form a lightweight material with varying shear strength characteristics. Contradicting results were found in the literature on the inclusion of particulate rubber to sand, where some experiments found that the inclusion of particulate rubber can increase the shear strength of the mixture, while other experiments stated that the addition of particulate rubber decreases the shear strength of the mixture. This research further investigates the inclusion of particulate rubber to sand and whether it can increase or decrease the shear strength characteristics of the mixture. For the experiment, a series of direct shear tests were performed on a poorly graded sand with a mean particle size of 0.32 mm mixed with recycled poorly graded particulate rubber with a mean particle size of 0.51 mm. The shear tests were performedon four normal stresses 30, 55, 105, 200 kPa at a shear rate of 1 mm/minute. Different percentages ofparticulate rubber content were used in the mixture i.e., 10%, 20%, 30% and 50% of sand dry weight at three density states, namely loose, slight dense, and dense state. The size ratio of the mixture,which is the mean particle size of the particulate rubber divided by the mean particle size of the sand, was 1.59. The results identified multiple parameters that can influence the shear strength of the mixture. The parameters were: normal stress, particulate rubber content, mixture gradation, mixture size ratio, and the mixture’s density. The inclusion of particulate rubber tosand showed a decrease to the internal friction angle and an increase to the apparent cohesion. Overall, the inclusion of particulate rubber did not have a significant influenceon the shear strength of the mixture. For all the dense states at the low normal stresses 33 and 55 kPa, the inclusion of particulate rubber showed aslight increase in the shear strength where the peak was at 20% rubber content of the sand’s dry weight. On the other hand, at the high normal stresses 105, and 200 kPa, there was a slight decrease in the shear strength.

Keywords: shear strength, direct shear, sand-rubber mixture, waste material, granular material

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