32 research outputs found

    Experimental Investigation of Circular High-Strength Concrete Columns Reinforced with Glass Fiber-Reinforced Polymer Bars and Helices under Different Loading Conditions

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    Existing design codes and guidelines do not adequately address the design of concrete columns reinforced with fiber-reinforced polymer (FRP) bars. Accordingly, a number of research studies investigated the behavior of FRP bar-reinforced concrete columns. However, the previous studies were limited to FRP bar-reinforced normal-strength concrete (NSC) columns. In this study, the behavior of glass fiber-reinforced polymer (GFRP) bar-reinforced high-strength concrete (HSC) specimens under different loading conditions was investigated in terms of axial load-carrying capacity, confinement efficiency of the GFRP helices, as well as the ductility and post-peak axial load-axial deformation response. The effects of the key parameters such as the type of the reinforcement (steel and GFRP), the pitch of the transverse helices, and the loading condition (concentric, eccentric, and four-point loading) on the performance of the specimens were investigated. It was observed that the GFRP bar-reinforced HSC specimen sustained similar axial load under concentric axial compression compared to its steel counterpart, but the efficiency of GFRP bar-reinforced HSC specimens in sustaining axial loads decreased with an increase in the axial load eccentricity. Direct replacement of steel reinforcement by the same amount of GFRP reinforcement in HSC specimens resulted in about 30% less ductility under concentric axial load. However, it was found that the ductility and post-peak axial load-axial deformation behavior of the GFRP bar-reinforced HSC specimens can be significantly improved by providing closely spaced helices

    Maximum axial load carrying capacity of Fibre Reinforced-Polymer (FRP) bar reinforced concrete columns under axial compression

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    In this study, a new equation is proposed to compute the maximum axial load carrying capacity of FRP bar reinforced concrete columns under axial compression. The equation proposed in this study was critically compared with the equations proposed in the previous research studies using a wide range of experimental data taken from the available literature. In general, it was found that computing the contribution of the FRP longitudinal bars in concrete columns based on the modulus of elasticity (stiffness) of the FRP bars provides more rational predictions than computing the contribution of the FRP longitudinal bars based on the ultimate tensile strength of the FRP bars. It was also found that using a concrete compressive strength-based empirical equation in estimating the axial strain in the FRP longitudinal bars in concrete columns provides more accurate predictions of the contribution of the longitudinal FRP bars in the axial load sustained by the FRP bar reinforced concrete columns

    The Cut-off Values of Triglycerides - Glucose Index for Metabolic Syndrome Associated with Type 2 Diabetes Mellitus

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    يؤدي حدوث متلازمة الأيض مع داء السكري من النوع 2 الى زيادة شدة المرض والوفيات المرتبطة بكل منهما. يوصى باستخدام مؤشر الجلوكوز الصائم للدهون الثلاثية (مؤشر TyG) كعلامة مفيدة للتنبؤ بمتلازمة التمثيل الغذائي. كان الهدف من هذه الدراسة هو تحديد القيم الحدية لنوع Triglyceride-Glucose لتشخيص متلازمة الأيض في داء السكري من النوع الثاني. تم جمع البيانات من مستشفيات بغداد في الفترة ما بين مايو وديسمبر 2019. وكان عدد المشاركين المؤهلين 424 حيث تم قياس الجلوكوز في الدم في وضع الصيام ، مستوى الدهون ، مستوى HbA1c. فضلا عن قياس ضغط الدم وتم حساب مؤشر Triglyceride-Glucose . تم الحصول على الموافقة الأخلاقية والموافقة المستنيرة .استخدم برنامج SPSS لمعالجة البيانات. أظهر مرضى السكري الذين يعانون من متلازمة الأيض زيادة مستوى مؤشر TyG. ازداد انتشار متلازمة الأيض مع زيادة مؤشر TyG. أظهر مؤشر TyG ارتباطًا كبيرًا مع جميع مكونات متلازمة الأيض. حيث ارتبط طرديا مع مستوى الكاوكوز في الدم ومحيط الخصر ,مستوى الدهون وضغط الدم الانبساطي بينما تناسب عكسيا مع مستوى الكولسترول النافع .مقدار قيمة القطع الأمثل للمؤشر كانت 9.14 ، 9.28 للذكور والإناث على التوالي.نستنج من الدراسة ان مؤشر TyG ملائم للكشف عن متلازمة الأيض في داء السكري من النوع الثاني       The co-occurrence of metabolic syndrome with type 2 diabetes mellitus (T2DM) will potentiate the morbidity and mortality that may be associated with each case. Fasting triglycerides-glucose index (TyG index) has been recommended as a useful marker to predict metabolic syndrome. Our study aimed to introduce gender-specific cut-off values of triglycerides- glucose index   for diagnosing metabolic syndrome associated with type 2 diabetes mellitus. The data were collected from Baghdad hospitals between May - December 2019. The number of eligible participants was 424. National cholesterol education program, Adult Treatment Panel III criteria were used to define metabolic syndrome. Measurement of fasting blood glucose, lipid profile, HbA1c level, blood pressure, and anthropometric were done and the triglyceride-glucose index was calculated. Ethical approval and informed consent were obtained .SPSS was used to analyze the data. Diabetic patients with metabolic syndrome showed an increased level of TyG Index. The prevalence of metabolic syndrome increased with increased TyG index quartiles. The TyG-Index showed significant correlations with all components of metabolic syndrome. The optimal cut-off value revealed 9.14, 9.28 for males and females respectively. In conclusion, TyG index is a good predictor of the presence of MetS in T2DM the TyG index, just measured in one laboratory test, is simple, informative and more suitable for the detection of metabolic syndrome in Iraqi type 2 diabetes mellitus

    Impact of the Coronavirus Pandemic (COVID-19) Lockdown on Mental Health and Well-Being in the United Arab Emirates

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    United Arab Emirates (UAE) has taken unprecedented precautionary measures including complete lockdowns against COVID-19 to control its spread and ensure the well-being of individuals. This study investigated the impact of COVID-19 and societal lockdown measures on the mental health of adults in the UAE. A cross-sectional study was conducted using an English and Arabic online questionnaire between May and June 2020. The psychological impact was assessed by the Impact of Event Scale-Revised (IES-R), and the social and family support impact was evaluated using questions from the Perceived Support Scale (PSS). A total of 4,426 participants (3,325 females and 1,101 males) completed the questionnaire. The mean IES-R score was 28.0 ± 14.6, reflecting a mild stressful impact with 27.3% reporting severe psychological impact. Over 36% reported increased stress from work, home and financial matters. Also, 43–63% of the participants felt horrified, apprehensive or helpless due to COVID-19. Females, younger participants, part-timers, and college or University graduates were more likely to have a high IES-R score (p \u3c 0.05). The majority of participants reported receiving increased support from family members, paying more attention to their mental health, and spending more time to rest and relax. The results of this study demonstrate the impact of the COVID-19 pandemic on mental health among the UAE residents and highlight the need to adopt culturally appropriate interventions for the general population and vulnerable groups, such as females and younger adults

    Assessment of Dietary and Lifestyle Responses After COVID-19 Vaccine Availability in Selected Arab Countries

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    The COVID-19 pandemic has been consistently associated with unhealthy lifestyle behaviors and dietary practices. This study aimed to assess the dietary and lifestyle behaviors of adults after COVID-19 vaccine availability and their attitude toward the vaccine in selected Arab countries. A cross-sectional survey-based study was conducted between October 2021 and December 2021 using Google Forms (n = 2259). A multi-component questionnaire was used to collect socio-demographic characteristics, attitudes toward the COVID-19 vaccine, and behavioral, dietary, and lifestyle responses after easing the restriction. Participants were given a score based on the sum of positive dietary and lifestyle changes. The generalized linear models were used to identify the association between positive dietary and lifestyle changes score and sociodemographic characteristics. Weight gain during the pandemic was reported by 39.5% of the participants, 36.1% reported ever getting infected with the COVID-19 virus, and 85% received at least one dose of the vaccine. The key adverse reactions of the COVID-19 vaccine were fatigue, headache, and joint pain, and the main reason for vaccination was protection against infection. Most participants were concerned about the vaccine side effects (45.8%) and inadequate testing (50.7%). After easing of restriction, 54.3% of the participants reduced the frequency of disinfecting objects, and 58.3% joined social events. Most dietary and lifestyle behaviors remained unchanged after vaccine availability but there was an increase in the time spent behind the screen for work (50.1%) and entertainment (42.9%). The results of the multivariate regression analyses revealed that older participants (p = 0.001), those with higher education (p = 0.010), and those working from home (p = 0.040) were more likely to have higher positive dietary and lifestyle changes scores. Although most participants were concerned about vaccine safety, low vaccine hesitancy rates were observed among the study sample. The availability of the COVID-19 vaccines resulted in loosening some of the safety social measures among Arab adults but the negative impact of the pandemic on dietary and lifestyle behaviors remained unaltered

    Assessment of Eating Habits and Lifestyle during Coronavirus Pandemic in the MENA region: A Cross-Sectional Study

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    © The Authors 2020. The coronavirus disease (COVID-19) has rapidly spread globally, forcing countries to apply lockdowns and strict social distancing measures. The aim of this study was to assess eating habits and lifestyle behaviors among residents of the Middle East and North Africa (MENA) region during the lockdown. A cross-sectional study among adult residents of the MENA region was conducted using an online questionnaire designed on Google Forms during April 2020. A total of 2970 participants from 18 countries participated in the current study. During the pandemic, over 30% reported weight gain, 6.2% consumed five or more meals per day compared to 2.2% before the pandemic (p\u3c0.001), and 48.8% did not consume fruits on daily basis. Moreover, 39.1% did not engage in physical activity, over 35% spent more than five hours per day on screens. A significant association between the frequency of training during the pandemic and the reported change in weight was found (p \u3c 0.001). A significantly higher percentage of participants reported physical and emotional exhaustion, irritability, and tension either all the time or a large part of the time during the pandemic (p \u3c 0.001). Although a high percentage of participants reported sleeping more hours per night during the pandemic, 63% had sleep disturbances. The study highlights that the lockdown due to the COVID-19 pandemic caused a variety of lifestyle changes, physical inactivity, and psychological problems among adults in the MENA region

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Performance evaluation of high strength concrete and steel fibre high strength concrete columns reinforced with GFRP bars and helices

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    This study presents the results of an experimental investigation on high strength concrete (HSC) and steel fibre high strength concrete (SFHSC) circular column specimens reinforced longitudinally and transversely with Glass Fibre-Reinforced Polymer (GFRP) bars and helices, respectively. The Influence of the type of the reinforcement (steel and GFRP), the pitch of the transverse reinforcement, the addition of the steel fibres and the loading condition (concentric, eccentric and four-point loading) on the performance of the specimens was investigated. The study showed that the GFRP bar reinforced HSC (GFRP-HSC) specimen is as efficient as the steel bar reinforced HSC (steel-HSC) specimen in sustaining concentric axial load. However, the maximum load sustained by the GFRP-HSC specimens under eccentric axial load was 10-12% lower than the maximum load sustained by the steel-HSC specimens. GFRP bar reinforced SFHSC (GFRP-SFHSC) specimens sustained 3-13% higher axial load and 14-27% greater ductility than GFRP-HSC specimens under different loading conditions. Furthermore, reducing the pitch of the GFRP helices in GFRP-SFHSC specimens resulted in a significant improvement in the ductility and the post-peak axial load-axial deformation behaviour of the specimens

    A New Method for Direct Tensile Testing of Concrete

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    Different testing methods were used in previous studies to measure the direct tensile strength of concrete. However, these methods experienced several major deficiencies such as stress concentration at the end of the specimens because of inadequate gripping and loading eccentricity and nonuniform fracture plane because of difficulties in aligning and centering the specimens during testing. This study presents the details of a new method of testing concrete under uniaxial tension. The method was developed to overcome the difficulties associated with testing methods adopted in the previous research studies. A full description of the wooden molds used in casting the specimens and the loading arrangements including the end grips, universal joints, and frame in which the specimens were tested under uniaxial tension are presented. As expected, all the tested specimens were fractured at the middle where the cross-sectional area was reduced by 20 %. Also, no crushing failure or slippage was observed at the ends of the tested specimens
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