Study of Different Pitched Roof Types

The roof is part of a buildings outer skin, and fulfils a range of functions: first it protects the space below it, open or closed, from the weather. Here the most important aspects are drainage precipitation effectively, providing protection from sun and wind, and affording privacy. Different roof structures can be used according to functional requirements or the design approach. In this paper, different Pitched roofs types were reviewed and compared and their advantages and disadvantages according to several comparison criteria were present. The Parameters of each of the systems, roof structure, roof battens, water proofing, thermal insulation methodologies, and Types of Finish are discussed. Keywords: Pitched roof, Mono pitch Roof, Gable roof, Mansard Roo

High SARS CoV2 antibody-prevalence among health care workers with variable exposure to COVID-19 patients: A cross-sectional university hospital study.

Background: During the COVID-19 pandemic, the pattern of medical services changed to minimize transmission to health care workers (HCWs) or hospitalized patients. Despite the care of COVID-19 patients in a special ward, new cases are accidentally discovered. This study aimed at determining the antibody seroprevalence among asymptomatic HCWs and the associated risks. Methods: The study involved 190 participants, including physicians, nurses, technicians, and administrative staff. All were inquired for sociodemographic, specialty, previous isolation, and previous infection, and their blood was tested for SARS-CoV2 antibody. Results: Of 190 HCWs; 72,1% were females, the mean age was 32.6±7.9 years, 10.5% were smokers, and 15.8% reported co-morbid illness. SARS CoV2 antibodies were found in 68 (35.8%); being IgG, IgM and both IgM and IgG in 47 (69.1%), 10 (14.7%) and 11 (16.2%) participants respectively. The prevalence was higher (47.6%) among HCWs of the COVID unit, [OR=1.7 (95% CI: 0.69-4.3)] and HCWs with previous COVID-19, OR:1.61 (95% CI:0.88-2.94). The prevalence was significantly lower among smokers (p=0.049), OR:0.29 (95% CI:0.08-1.01), and significantly higher in HCWs who recalled cough (p=0.036) OR: 1.97 (95% CI: 1.05-3.69). The likelihood of antibody seropositivity increased in technicians [OR:2.02 (95% CI: 0.92-4.44)], followed by physicians [OR:1.7 (95% CI: 0.7-4.33)] while the odds ratio was low among nurses [OR:0.58 (95% CI: 0.32-1.07). Conclusion: A considerable proportion of antibody positive HCWs had evidence of past SARS CoV2. Provision of adequate personal protective equipment and periodic screening of HCWs are urgently needed to lessen the transmission within the health care settings

Hepatobiliary manifestations following two-stages elective laparoscopic restorative proctocolectomy for patients with ulcerative colitis: A prospective observational study

BACKGROUNDHepatobiliary manifestations occur in ulcerative colitis (UC) patients. The effect of laparoscopic restorative proctocolectomy (LRP) with ileal pouch anal anastomosis (IPAA) on hepatobiliary manifestations is debated.AIMTo evaluate hepatobiliary changes after two-stages elective laparoscopic restorative proctocolectomy for patients with UC.METHODSBetween June 2013 and June 2018, 167 patients with hepatobiliary symptoms underwent two-stage elective LRP for UC in a prospective observational study. Patients with UC and having at least one hepatobiliary manifestation who underwent LRP with IPAA were included in the study. The patients were followed up for four years to assess the outcomes of hepatobiliary manifestations.RESULTSThe patients' mean age was 36 +/- 8 years, and males predominated (67.1%). The most common hepatobiliary diagnostic method was liver biopsy (85.6%), followed by Magnetic resonance cholangiopancreatography (63.5%), Antineutrophil cytoplasmic antibodies (62.5%), abdominal ultrasonography (35.9%), and Endoscopic retrograde cholangiopancreatography (6%). The most common hepatobiliary symptom was Primary sclerosing cholangitis (PSC) (62.3%), followed by fatty liver (16.8%) and gallbladder stone (10.2%). 66.4% of patients showed a stable course after surgery. Progressive or regressive courses occurred in 16.8% of each. Mortality was 6%, and recurrence or progression of symptoms required surgery for 15%. Most PSC patients (87.5%) had a stable course, and only 12.5% became worse. Two-thirds (64.3%) of fatty liver patients showed a regressive course, while one-third (35.7%) showed a stable course. Survival rates were 98.8%, 97%, 95.8%, and 94% at 12 mo, 24 mo, 36 mo, and at the end of the follow-up.CONCLUSIONIn patients with UC who had LRP, there is a positive impact on hepatobiliary disease. It caused an improvement in PSC and fatty liver disease. The most prevalent unchanged course was PSC, while the most common improvement was fatty liver disease

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background: Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods: The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings: Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation: Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions

Shear Behaviour of RC Beams Strengthened by Various Ultrahigh Performance Fibre-Reinforced Concrete Systems

This study presents a numerical investigation on the shear behaviour of shear-strengthened reinforced concrete (RC) beams by using various ultrahigh performance fibre-reinforced concrete (UHPFRC) systems. The proposed 3D finite element model (FEM) was verified by comparing its results with those of experimental studies in the literature. The validated numerical model is used to analyse the crucial parameters, which are mainly related to the design of RC beams and shear-strengthened UHPFRC layers, such as the effect of shear span-to-depth ratio on the shear behaviour of the strengthened or nonstrengthened RC beams and the effect of geometry and length of UHPFRC layers. Moreover, the effect of the UHPFRC layers’ reinforcement ratio and strengthening of one longitudinal vertical face on the mechanical performance of RC beams strengthened in shear with UHPFRC layers is investigated. Results of the analysed beams show that the shear span-to-depth ratio significantly affects the shear behaviour of not only the normal-strength RC beams but also the RC beams strengthened with UHPFRC layers. However, the effect of shear span-to-depth ratio has not been considered in existing design code equations. Consequently, this study suggests two formulas to estimate the shear strength of normal-strength RC beams and UHPFRC-strengthened RC beams considering the effect of the shear span-to-depth ratio

مساهمة في تقييم عامل تعديل الاستجابة الزلزالية للجمل الإنشائية المعزولة قاعدياً

شهدت الهندسة الإنشائية في السنوات الأخيرة العديد من التقنيات الحديثة التي ساعدت على تحسين أداء المباني في مواجهة أحمال الطبيعة كالرياح والزلازل ولعلّ من أبرزها تقنية العزل الزلزالي القاعدي والتي انتشرت بدورها بشكل واسع واستخدمت في العديد من دول العالم . هذا الانتشار الكبير في استخدام هذه التقنية فرض علينا كمهندسين إنشائيين الإلمام بطرق تصميم هكذا نوع من المباني والتوسع في طرق التحليل الخاصة بها . و باعتبار عامل تعديل الاستجابة الزلزالية أو ما يسمى بمعامل السلوك اللامرن (العامل R ) من البارامترات الهامة في عملية التصميم الإنشائي للمباني المعرضة للخطر الزلزالي كان الهدف من هذا البحث دراسة قيم العامل RI لجمل المباني المعزولة قاعدياً و مقارنتها مع ما تنص عليها الكودات العالمية التي تعنى بهكذا نوع من الجمل الإنشائية والتي وجدنا أنها تبدي نوعاً من التحفظ تجاه قيم العامل  RI و الذي ينعكس بدوره على اقتصادية التصميم. ومن أجل الوصول لغاية البحث قمنا باستخدام التحليل الاستاتيكي اللاخطي Pushover Analysis  على مجموعة من نماذج المباني ودراسة تأثير تغيير بعض البارمترات مثل عدد الطوابق و نسب التخامد و الصلابة على سلوك هذه النماذج بالإضافة إلى إجراء تحليل ديناميكي لاخطي للنماذج باعتماد السجل الزمني لزلزال السينترو ، والتوصل إلى قيم للعامل RI والتي كانت بدورها تختلف عما ورد عليه في الكودات العالمية مثل ASCE 7-16 , IBC2000

مساهمة في دراسة و تقييم الانهيار المتتابع لمبنى إطاري من البيتون المسلح مقاوم للزلازل وفق مواقع إزالة محددة للعناصر الشاقولية الحاملة

إن الأحداث القصوى (هجمات إرهابية , زلازل , حرائق , انفجارات ,..) تشكل تهديداً خطيراً على  مختلف أنواع المباني المهمة والخاصة  والتي من الممكن أن تخضع لمثل هذه الأحداث  حيث أن كل حدث منها قد يسبب فشل موضعي  والذي يسبب بدوره سلسلة  من الفشل وبالتالي انهيار كامل المنشأ أو جزء كبير منه  مترافق مع خسائر بشرية ومادية كبيرة وهذا ما يسمى بالانهيار المتتابع . من الصعب التنبؤ بمقدار او احتمالية مثل هذه الاحداث وبالتالي ليس من العملي والمتاح تصميم المنشآت ضد مثل هذه الاحداث بالطرق التقليدية وكذلك بالأحمال التقليدية ,حيث ان معايير التصميم في الوقت الحاضر تسعى لتخفيض المخاطر وتوفير مستوى من التحكم بالحد الادنى  بالانهيار المتتابع من خلال دمج مفهوم عدم حساسية المنشآت للضرر الموضعي مع مفاهيم التصميم في الكودات وبالتالي الهدف يكمن في السيطرة على العواقب وليس اتخاذ اجراءات ضد الحدث المتطرف نفسه. الهدف الرئيس للبحث هو اختبار مقاومة الإطارات العزمية المقاومة للزلازل المصممة وفق الكود العربي السوري على الانهيار المتتابع وفق المعايير الموضوعة من قبل وزارة الدفاع عن طريق ازالة أعمدة حسب التوصيات وتقييم النتائج