102 research outputs found
Improvement of Sn-Pp Solder by addition Ag Element
هذا البحث يختص بدراسة لحام سبائك قصدير رصاص على أجزاء مختلفة من الفولاذ واطئ الكاربون، سبيكة البراص والنحاس. اذ يتم دراسة الخواص الميكانيكية والكهروكيميائية وكذلك الخواص الكهربائية للسبيكة الناتجة من عملية الصب وبعد لحامها على الأجزاء المختلفة. وقد تم تحقيق أهداف هذا البحث من خلال الاختبارات التي شملت اختبار البنية المجهرية، اختبار الشد، اختبار تافل (فحص تيار ومقاومة التآكل)، اختبار التوصيلية الكهربائية. ومن النتائج التي تم الحصول عليها حيث كانت مقاومة الشد اعلى ما يمكن لسبيكة (97%Sn+1.5%Pb+1.5%Ag) عند مقارنتها مع السبائك أخر وكانت أفضل نتيجة لحام على قطعة الفولاذ واطئ الكاربون عند مقارنتها مع مقاومة الشد للملحومات الأخرى على سبيكة البراص او النحاس ونتائج التوصيل الكهربائي أيضا أظهرت سبيكة (97%Sn + 1.5%Pb + 1.5%Ag) اعلى توصيلية كهربائية، وذلك بسبب تأثير إضافة الفضة على سبيكة قصدير رصاص. وكانت السبيكة (60%Sn-40%Pb) أفضل ما يمكن عند اجراء فحص مقاومة التآكل وقد أجري الفحص في ماء البحر (sea water).This research is devoted to study the soldering of Sn-Pb alloy on different part (copper, low carbon steel, brass) .the Sn-Pb alloy produced in different percentage of Pb and addition of Ag by casting, and show the effect on electrochemical, mechanical and electrical properties. The mechanical and physical properties includes microstructure, tensile, electrical conductivity and electrochemical have been achieved for this research through tests that include microstructure test, tensile test, tafel Potentiostatic, electrical conductivity test, X-Ray Fluorescent Analysis (XRF).
From results obtained in this study, a higher tensile strength was found for (Sn97%+Pb1.5%+Ag1.5%) when its compared with other alloy, and the best result in soldering was with carbon steel because it has higher strength compared with brass andcopper. The electrical conductivity result showed that the alloy (Sn97%+Pb1.5%+Ag1.5%) has higher electrical conductivity
Assessing information and communication technology in surgical training, Sudan as example
No Abstrac
An Analysis of Export Restriction Rules and Proposals Under the WTO
هذه المذكرة هي نسخة منقحة عن ورقة بحثية سرية حول القيود المفروضة على المفاوضات نات الصلة بالأمن الغذائي تحت رعاية منظمة التجارة العالمية (WTO) . تتألف النسخة الكاملة لهذه الورقة من عنصرين: يمنح العنصر الأول خطه للإطار القانوني القائم ومقترحات التفاوض على قيود الصادرات. أما العنصر الثاني. فهو يمنح مقترحات التفاوض. وبسبب السرية. إن العنصر الأول فقحد متاح للعامة وسيتم عرضه في هذه المذكرة. تتمحور هذه المذكرة حول ثلاثة أقسام حيث يتناول القسم الأول أهم معاهدات منظمة التجارة العالمية (WTO) . وبالأخص الاتفاقية العامة للتعرفة و التجارة الدولية ١٩٩٤ (1994 GATT) واتفاقية الزراعة (AoA). كما أنه يناقش كيف يسهم التباس المصطلحات في هذه المعاهدات في خلق التحديات على صعيد التنظيم الفعال لقيود الصادرات. أما القسم الثاني. فهو يعرض المقترحات العديدة لأعضا، منظمة التجارة العالمية (WTO) والتي تهدف إلى توضيح الالتباسات أو ملء الثغرات في المخططات التنظيمية القائمة. ويناقش القسم الثالث المعاهدات التجارية الإقليمية بما فيها شراكة التجارة والاستثمار عبر الأطلسي (TTIP). اتفاقية الاقتصاد والتجارة الشاملة (CETA)‘ والشراكة عبر المحيط الهادئ (TTP)، بالإضافة الى اتفاقيات أخرى أقل شهرة لمنظمة التجارة العالمية (WTO).This memorandum is a redacted version of a confidential research paper on export restriction negotiations in relation to food security under the auspices of the World Trade Organization (WTO). The complete version of this paper has two components: the first provides a sketch of the existing legal framework and negotiation proposals on export restriction; the second provides negotiation proposals. Due to confidentiality considerations, only the first component of analysis is publicly available and presented here. This memorandum is organized into three parts. The first part elaborates on the most relevant WTO treaties, namely the General Agreement on Tariffs and Trade 1994 (GATT 1994) and the Agreement on Agriculture (AoA). It discusses how ambiguity in the terms in these treaties poses challenges to effective regulation of export restriction. The second part presents proposals from several WTO Members that seek to clarify the ambiguities or fill the void in the existing regulatory schemes. The third part discusses regional trade treaties, including Transatlantic Trade and Investment Partnership (TTIP), Comprehensive Economic and Trade Agreement (CETA), and Trans- Pacific Partnership (TTP), along with other less prominent WTO agreements
Acquired pure megakaryocytic aplasia successfully treated with cyclosporine
Acquired pure megakaryocytic aplasia is a rare hematological disorder characterized by thrombocytopenia with absent or markedly reduced megakaryocytes in the bone marrow. We report a case of a 25-year-old male diagnosed as acquired pure megakaryocytic aplasia. Treatment with prednisone and intravenous immunoglobulin failed, but he was successfully treated with cyclosporine, with complete remission after 90 days and normal platelet count maintained thereafter
The Effect of Vitamin D treatment on COVID 19- Patients, an Inverted Propensity Score Weighting (IPSW), and Inverted Probability of Treatment Weighting (IPTW) Analyzed Study
Background
Vitamin D3 (1,25(OH)2 cholecalciferol) as a treatment for COVID 19 patients is being disputed, and a clear clinical benefit is not being confirmed.
Methods
A retrospective evaluation for COVID-19 patients who were treated with various cumulative doses of vitamin D. Data was extracted from the COVID-19 database, it included patients admitted to three hospitals in Amman, Jordan. Characteristics of patients were tabulated and compared for all-cohort, and propensity score index (PSI) adjustment, The comparison was based on two vitamin D strata ((≤ 149,000 i.u. and > 150,000 i.u.). Logistic regression analysis was utilized to predict recovery, the need for oxygen, and all-cause mortality for all-cohort, IPSW, and IPTW patients, based on vitamin D cumulative doses during their hospital stay.
Results
1131 all-cohort and 768 PSI-adjusted patients were recruited. Except for antibiotics and antivirals, all other characteristics were balanced (P = NS). There were 1017 patients on vitamin D, 847 received cumulative ≤ 149,000 i.u., and 170 patients received cumulative dose ≥ 150,000 i.u. (Range 1000 – 385000). It was demonstrated that escalating cumulative doses of vitamin D did not contribute to the assessed outcomes; all-cohort patients (OR = 1.000, 95% C.I. 1.000 to 1.000), IPSW (OR = 1.000, 95% C.I. 1.000 to 1.000), and the IPTW (OR = 1.000, 95% C.I. 1.000 to 1.000).
Conclusion
In our patients’ cohorts, we could not demonstrate a beneficial effect for vitamin D therapy in COVID-19 patients for recovery, the need for home oxygen, and all-cause mortality, by hospital discharge
Effect of treatment with exenatide and pioglitazone or basal-bolus insulin on diabetic neuropathy: a substudy of the Qatar Study
Role of adjuvant metformin therapy on HA1C in type 1 diabetes
BackgroundAdequate glycaemic control is a protective strategy against diabetic complication that achieved manly with insulin therapy, studies have shown that type 1 diabetic patients had a reduced insulin sensitivity, on view of this fact, metformin as an insulin sensitizing agent was used in trials as an adjuvant medication to the insulin. AimsCurrent study aimed to summarize the benefit of adjuvant metformin on HA1C in type 1 diabetes on glycaemic control.Methods A systematic electronic search was conducted including the Pub Med, Google Scholar, and EBSCO using the following terms in different combinations: metformin, diabetes, HA1c, and C- peptide. Out of two hundred and four articles, only six were included.Results Six randomized control trials were identified, aimed to investigate the role of adjuvant metformin on glycaemic control in type 1 diabetes patients. Metformin in dose ranging between 1–2g per day were used for at least three months. Significant HA1c reduction was shown in two out of six trials.ConclusionAdministering adjunctive metformin therapy in type 1 diabetic patients associated with modest reduction in HA1c, improve insulin resistance as indicated by reduce daily insulin requirement.
Global burden of chronic respiratory diseases and risk factors, 1990–2019: an update from the Global Burden of Disease Study 2019
Background Updated data on chronic respiratory diseases (CRDs) are vital in their prevention, control, and treatment in the path to achieving the third UN Sustainable Development Goals (SDGs), a one-third reduction in premature mortality from non-communicable diseases by 2030. We provided global, regional, and national estimates of the burden of CRDs and their attributable risks from 1990 to 2019.
Methods Using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we estimated mortality, years lived with disability, years of life lost, disability-adjusted life years (DALYs), prevalence, and incidence of CRDs, i.e. chronic obstructive pulmonary disease (COPD), asthma, pneumoconiosis, interstitial lung disease and pulmonary sarcoidosis, and other CRDs, from 1990 to 2019 by sex, age, region, and Socio-demographic Index (SDI) in 204 countries and territories. Deaths and DALYs from CRDs attributable to each risk factor were estimated according to relative risks, risk exposure, and the theoretical minimum risk exposure level input.
Findings In 2019, CRDs were the third leading cause of death responsible for 4.0 million deaths (95% uncertainty interval 3.6–4.3) with a prevalence of 454.6 million cases (417.4–499.1) globally. While the total deaths and prevalence of CRDs have increased by 28.5% and 39.8%, the age-standardised rates have dropped by 41.7% and 16.9% from 1990 to 2019, respectively. COPD, with 212.3 million (200.4–225.1) prevalent cases, was the primary cause of deaths from CRDs, accounting for 3.3 million (2.9–3.6) deaths. With 262.4 million (224.1–309.5) prevalent cases, asthma had the highest prevalence among CRDs. The age-standardised rates of all burden measures of COPD, asthma, and pneumoconiosis have reduced globally from 1990 to 2019. Nevertheless, the age-standardised rates of incidence and prevalence of interstitial lung disease and pulmonary sarcoidosis have increased throughout this period. Low- and low-middle SDI countries had the highest age-standardised death and DALYs rates while the high SDI quintile had the highest prevalence rate of CRDs. The highest deaths and DALYs from CRDs were attributed to smoking globally, followed by air pollution and occupational risks. Non-optimal temperature and high body-mass index were additional risk factors for COPD and asthma, respectively.
Interpretation Albeit the age-standardised prevalence, death, and DALYs rates of CRDs have decreased, they still cause a substantial burden and deaths worldwide. The high death and DALYs rates in low and low-middle SDI countries highlights the urgent need for improved preventive, diagnostic, and therapeutic measures. Global strategies for tobacco control, enhancing air quality, reducing occupational hazards, and fostering clean cooking fuels are crucial steps in reducing the burden of CRDs, especially in low- and lower-middle income countries.
Funding Bill & Melinda Gates Foundation
Burden of non-communicable diseases among adolescents aged 10–24 years in the EU, 1990–2019: a systematic analysis of the Global Burden of Diseases Study 2019
Background: Disability and mortality burden of non-communicable diseases (NCDs) have risen worldwide; however, the NCD burden among adolescents remains poorly described in the EU. Methods: Estimates were retrieved from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Causes of NCDs were analysed at three different levels of the GBD 2019 hierarchy, for which mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) were extracted. Estimates, with the 95% uncertainty intervals (UI), were retrieved for EU Member States from 1990 to 2019, three age subgroups (10–14 years, 15–19 years, and 20–24 years), and by sex. Spearman's correlation was conducted between DALY rates for NCDs and the Socio-demographic Index (SDI) of each EU Member State. Findings: In 2019, NCDs accounted for 86·4% (95% uncertainty interval 83·5–88·8) of all YLDs and 38·8% (37·4–39·8) of total deaths in adolescents aged 10–24 years. For NCDs in this age group, neoplasms were the leading causes of both mortality (4·01 [95% uncertainty interval 3·62–4·25] per 100 000 population) and YLLs (281·78 [254·25–298·92] per 100 000 population), whereas mental disorders were the leading cause for YLDs (2039·36 [1432·56–2773·47] per 100 000 population) and DALYs (2040·59 [1433·96–2774·62] per 100 000 population) in all EU Member States, and in all studied age groups. In 2019, among adolescents aged 10–24 years, males had a higher mortality rate per 100 000 population due to NCDs than females (11·66 [11·04–12·28] vs 7·89 [7·53–8·23]), whereas females presented a higher DALY rate per 100 000 population due to NCDs (8003·25 [5812·78–10 701·59] vs 6083·91 [4576·63–7857·92]). From 1990 to 2019, mortality rate due to NCDs in adolescents aged 10–24 years substantially decreased (–40·41% [–43·00 to –37·61), and also the YLL rate considerably decreased (–40·56% [–43·16 to –37·74]), except for mental disorders (which increased by 32·18% [1·67 to 66·49]), whereas the YLD rate increased slightly (1·44% [0·09 to 2·79]). Positive correlations were observed between DALY rates and SDIs for substance use disorders (rs=0·58, p=0·0012) and skin and subcutaneous diseases (rs=0·45, p=0·017), whereas negative correlations were found between DALY rates and SDIs for cardiovascular diseases (rs=–0·46, p=0·015), neoplasms (rs=–0·57, p=0·0015), and sense organ diseases (rs=–0·61, p=0·0005). Interpretation: NCD-related mortality has substantially declined among adolescents in the EU between 1990 and 2019, but the rising trend of YLL attributed to mental disorders and their YLD burden are concerning. Differences by sex, age group, and across EU Member States highlight the importance of preventive interventions and scaling up adolescent-responsive health-care systems, which should prioritise specific needs by sex, age, and location. Funding: Bill & Melinda Gates Foundation
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