46 research outputs found

    Magnetic monolayer Li2_{2}N: Density Functional Theory Calculations

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    Density functional theory (DFT) calculations are used to investigate the electronic and magnetic structures of a two-dimensional (2D) monolayer Li2_{2}N. It is shown that bulk Li3_{3}N is a non-magnetic semiconductor. The non-spinpolarized DFT calculations show that pp electrons of N in 2D Li2_{2}N form a narrow band at the Fermi energy EFE_{\rm{F}} due to a low coordination number, and the density of states at the Fermi energy (g(EFg(E_{\rm{F}})) is increased as compared with bulk Li3_{3}N. The large g(EFg(E_{\rm{F}}) shows instability towards magnetism in Stoner's mean field model. The spin-polarized calculations reveal that 2D Li2_{2}N is magnetic without intrinsic or impurity defects. The magnetic moment of 1.0\,μB\mu_{\rm{B}} in 2D Li2_{2}N is mainly contributed by the pzp_{z} electrons of N, and the band structure shows half-metallic behavior. {Dynamic instability in planar Li2_{2}N monolayer is observed, but a buckled Li2_{2}N monolayer is found to be dynamically stable.} The ferromagnetic (FM) and antiferromagnetic (AFM) coupling between the N atoms is also investigated to access the exchange field strength. {We found that planar (buckled) 2D Li2_{2}N is a ferromagnetic material with Curie temperature TcT_{c} of 161 (572) K.}Comment: Euro Phys. Lett. 2017 (Accepted

    Waveform Effects on the Operation of the Parallel-Bridge Rectifier System and the Field Modulated Generator System

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    The Nature of Motivation in Saudi EFL Context: An Overview

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    This article reviews past research done on English as a foreign language learning motivation in Saudi Arabian universities from the last twenty years, in order to evaluate its impact on learning process and to find out the nature of motivation of EFL learners. It focuses on the studies of psychological theories of motivation which were tested in FL classrooms for their validation in Saudi universities. It has been observed that there are significant changes in EFL learners’ learning level of motivation at different times in different contexts. Additionally, this review emphasizes the complexities seen in the relationships between teaching and learner motivation. Eventually, an attempt is made to clarify certain emerging truths and point out the most promising research directions. Keywords: Motivation; EFL learning process; Saudi Arabian universities DOI: 10.7176/JLLL/98-05 Publication date:September 30th 202

    Management of diabetes and arthritis –A systematic review

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    Purpose: Diabetes is a metabolic syndrome with reported musculoskeletal  effects. This systemic review aimed to identify a relationship between  diabetes and arthritis; disease-related risk factors, the effect of diet in disease management and the effect of anti-arthritic drugs on diabetes  treatment.Methods: This study analysed 20 articles identified and selected according to the study criteria. PRISMA guidelines were used for identification and screening of literature. Data search covered several primary databases, including Pubmed, Wiley library, Scopus, Clinical Trial Registry, etc.Results: The study findings suggest a significant correlation between  diabetes and arthritis. Obesity, impaired glucose tolerance (MS  components), vascular cell adhesion molecule 1 (VCAM-1) hypertension and dyslipidemia are the most common risk factors leading to disease progression. Omega -3-fatty acid showed no protective effect on disease condition.Conclusion: The findings indicate that anti-tumor necrosis factor (Tnf)-α, disease modifying antirheumatic drugs, and Interleukin receptors  antagonist improved the efficacy of diabetic medication and maintained blood sugar levels. However, Tnf-α reduced glucose intolerance, and therefore, its therapeutic use in conjunction with diabetic medications should be limited.Keywords: Diabetes, Arthritis, Risk factors, Diet, Pathogenesis, Disease progression, Medicatio

    Revealing the Yield and Quality Responses of Soybean Advanced Lines under Semi-Arid Conditions

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    Background: Soybean as human diet is a rich source of protein and oil. It also plays a vital role in livestock and poultry industries. Objective of this work is to exploit the local soybean germplasm for semi-arid conditions.Methods: The experiment was conducted in Randomized Complete Block Design with three replications. Plant × plant and row × row distance was maintained as 4 inch and 1ft respectively. At maturity data for plant height, days to 50% flowering, no. of branches, no. of pods, grains per pod and grain yield per hectare were recorded.  Furthermore, oil percentage, protein percentage, omega-3, omega-6, omega-9, palmitic acid and stearic acids were also measured.Results: All genotypes showed highly significant difference from each other for selected traits. Grain yield per hectare was significant in genotypes such as CN-5, FS-10, E-402 and SH-1274 as compared to Faisal soybean (check). Protein and oil percentage were significantly more in CN-5, HS-17 and FS-10. Branches per plant significantly correlated with the yield but protein and oil percentage negatively correlated with each other. PCA indicated that only four out of 13 PCAs exhibited more than 1 Eigen value and showed 76.53 % variation. All traits for yield and quality were presented in PCA1, PCA2 and PCA3. Biplot indicated that genotype CN-5, SH-1274 and HB-17 falls in the positive portion that perform good.Conclusion: Soybean genotypes CN-5 and FS-10 showed the more yield with high protein and oil percentage as compared to check variety and could be used in semi-arid environments.Keywords: Oilseeds; Soybean; Semi-arid; Yield; Quality   

    Assessment of hospital pharmacists' clinical knowledge and practical skill levels for pharmaceutical care in Madinah, Saudi Arabia

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    Purpose: To evaluate hospital pharmacists’ clinical knowledge and practical skill levels for pharmaceutical care.Methods: A quasi-experimental prospective longitudinal study design was used to evaluate the level of clinical skills with problem-based learning (PBL) sessions. Pharmacists’ in three different government hospitals in Madinah, Saudi Arabia recorded their responses or assessments in their work manuals for preparing reports. Instructors encouraged interactive learning by presenting case studies, in which pharmacists had to interpret medical history and clinical assessments of various body systems. Course learning design also focused on drug use evaluation, monitoring plans, and reaching clinical evidencebased decision-making.Results: A total of two hundred and fifty-five (255) hospital pharmacists participated in the study. The study sample was comprised of 128 (50.9 %) males and 127 (49.1 %) females. A significant (p < 0.01) difference was noticed between genders (male: 47.91 ± 7.15, female: 50.31 ± 4.88) for total mean scores of clinical skills. Cronbach’s alpha reliability coefficient for case data recitation was 0.91, while clinical assessment skills coefficient was 0.89. Overall, pharmacists reported that they “agree” (4.01 ± 0.67) that they acquired the ability to use case data recitation taught in the PBL; they also reported a positive evaluation (4.48 ± 0.58) of their ability to perform clinical data assessment.Conclusion: The findings indicate that pharmacist’s self-confidence to perform clinical assessment activities is low. Lack of confidence remains a critical education issue among pharmacists in the study setting.Keywords: Clinical pharmacy, Problem-based learning, Clinical skills, Pharmacist focus group, Therapeutics, Pharmaceutical car

    Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic

    Global, regional, and national incidence of six major immune-mediated inflammatory diseases: findings from the global burden of disease study 2019

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    Background The causes for immune-mediated inflammatory diseases (IMIDs) are diverse and the incidence trends of IMIDs from specific causes are rarely studied. The study aims to investigate the pattern and trend of IMIDs from 1990 to 2019. Methods We collected detailed information on six major causes of IMIDs, including asthma, inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, psoriasis, and atopic dermatitis, between 1990 and 2019, derived from the Global Burden of Disease study in 2019. The average annual percent change (AAPC) in number of incidents and age standardized incidence rate (ASR) on IMIDs, by sex, age, region, and causes, were calculated to quantify the temporal trends. Findings In 2019, rheumatoid arthritis, atopic dermatitis, asthma, multiple sclerosis, psoriasis, inflammatory bowel disease accounted 1.59%, 36.17%, 54.71%, 0.09%, 6.84%, 0.60% of overall new IMIDs cases, respectively. The ASR of IMIDs showed substantial regional and global variation with the highest in High SDI region, High-income North America, and United States of America. Throughout human lifespan, the age distribution of incident cases from six IMIDs was quite different. Globally, incident cases of IMIDs increased with an AAPC of 0.68 and the ASR decreased with an AAPC of −0.34 from 1990 to 2019. The incident cases increased across six IMIDs, the ASR of rheumatoid arthritis increased (0.21, 95% CI 0.18, 0.25), while the ASR of asthma (AAPC = −0.41), inflammatory bowel disease (AAPC = −0.72), multiple sclerosis (AAPC = −0.26), psoriasis (AAPC = −0.77), and atopic dermatitis (AAPC = −0.15) decreased. The ASR of overall and six individual IMID increased with SDI at regional and global level. Countries with higher ASR in 1990 experienced a more rapid decrease in ASR. Interpretation The incidence patterns of IMIDs varied considerably across the world. Innovative prevention and integrative management strategy are urgently needed to mitigate the increasing ASR of rheumatoid arthritis and upsurging new cases of other five IMIDs, respectively. Funding The Global Burden of Disease Study is funded by the Bill and Melinda Gates Foundation. The project funded by Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38)
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