64 research outputs found

    Metallo-Anti-aromatic Al4Na4 and Al4Na3- compounds: A theoretical investigation

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    We propose a theoretical investigation in this paper to understand the bonding and structural properties of neutral Al4Na4 and anion Al4Na3- clusters. We show that the Al4 species in Al4Na4 and Al4Na3- clusters is a rectangular planar structure with alternate pi-bonds and hence satisfying the basic criteria for anti-aromaticity. We prove that the Al4Na4 and Al4Na3- clusters are metallo-anti-aromatic compounds

    Structural, electronic and bonding properties of zeolite Sn-Beta: A periodic density functional theory study

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    The structural, electronic and the bonding properties of the Sn-BEA are investigated by using the periodic density functional theory. Each of the 9 different T-sites in the BEA were substituted by the Sn atom and all the 9 geometries were completely optimized using the plane wave basis set in conjunction with the ultra-soft pseudopotential. On the basis of the structural and the electronic properties, it has been demonstrated that the substitution of the Sn atom in the BEA framework is an endothermic process and hence the incorporation of the Sn in the BEA is limited. The lowest unoccupied molecular orbitals (LUMO) energies have been used to characterize the Lewis acidity of each T-site. On the basis of the relative cohesive energy and the LUMO energy, T2 site is shown to be the most favorable site for the substitution of Sn atom in the BEA framework.Comment: 17 pages, 5 figures, 2 Table

    Density functional investigation of the interaction of acetone with small gold clusters

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    The structural evolution of Aun (n = 2, 3, 5, 7, 9, and 13) clusters and the adsorption of organic molecules such as acetone, acetaldehyde, and diethyl ketone on these clusters are studied using a density functional method. The detailed study of the adsorption of acetone on the Aun clusters reveals two main points. (1) The acetone molecule interacts with one gold atom of the gold clusters via the carbonyl oxygen. (2) This interaction is mediated through back donation mainly from the spd-hybridized orbitals of the interacting gold atom to the oxygen atom of the acetone molecule. In addition, a hydrogen bond is observed between a hydrogen atom of the methyl group and another gold atom (not involved in the bonding with carbonyl oxygen). Interestingly, the authors notice that the geometries of Au9 and Au13 undergo a significant flattening due to the adsorption of an acetone molecule. They have also investigated the role of the alkyl chain attached to the carbonyl group in the adsorption process by analyzing the interaction of Au13 with acetaldehyde and diethyl ketone

    Comparative study between interlock nailing and dynamic compression plating in humerus diaphyseal fractures in its functional and surgical outcome

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    Background: The aim of the study was to analyse compare study between interlock nailing and dynamic compression plating in humerus diaphyseal fractures in its functional and surgical outcome. Methods: The 2019 to 2022, patients were randomly divided into two groups with the help of computer-generated coded envelopes, group A (humerus diaphyseal fractures treated with dynamic compression plating) and group B (humerus diaphyseal fractures treated with interlock nailing) with 20 patients in each group. Outcomes were evaluated based on operative time, blood loss, neurovascular deficit, surgical site infection, union, shoulder stiffness, constant Murley score, Mayo elbow performance index at 1 year of follow up. Results: On radiology as non-union and union, most common study participants show union, on follow up of 1 year constant Murley score and Mayo elbow performance index was calculated and constant Murley score was more in patients treated with dynamic compression plating, shoulder stiffness was more in patients treated with interlock nailing. However blood loss was more in patients treated with dynamic compression plating. Conclusions: The result of our study shows that interlock nailing is associated with less blood loss but it is associated with decreased shoulder function postoperatively and marked shoulder stiffness which is more than patients treated with dynamic compression plating. Hence dynamic compression plating should be considered gold standard for operative treatment of humerus shaft fracture

    A novel approach for segmentation and classification of brain MR images using cluster deformable based fusion approach.

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    Segmentation of tumor form brain MR images is the most important and tedious task in the medical field. In this paper, A Cluster deformable based fusion approach which uses both deformable and K-Means clustering scheme for Segmentation is discussed. The features of tumor and non tumor cases are extracted with the use of the Power Local Binary Pattern (LBP) Operator after completion of the segmentation process. The extracted features are fed to Naive Bayes classifier to perform the process of classification. Here, the validation of the proposed system is done using standard validation methods such as accuracy, specificity, sensitivity and RoC metrics. The developed method is applied for MR images collected from standard SimBRATS database. Experimentation results shows that the proposed method performs better when compared to the traditional clustering and deformable methods and this scheme got accuracy of 84.8%

    Buccal mucosa graft urethroplasty for anterior urethral stricture: A single-centre experience

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    Background :To evaluate the outcome and complications after using BMG for anterior urethral stricture. Procedure: This is a retrospective evaluation of prospectively maintained database. A total of 78 patients were operated from August 2012 to September 2019. Patients were evaluated by using IPSS score, uroflometry, post void residual urine and radiological studies. All patients were operated by using combined regional and general anaesthesia. Buccal mucosa was used in all except three where lingual mucosa was also harvested. The catheter was removed at 3-4 weeks after surgery and patients were followed up at one, three and six months, and then three monthly thereafter.The procedure was considered successful if no intervention was required after surgery. Conclusion: In 78 patient’s total of 89 procedures have been done over seven years. The procedure was successful in 84.93%, and it failed in 11 patients over a mean follow up of 45 months (7-59 months). In three patients, single DVIU was sufficient whereas in four regular CIC was required after DVIU. In four patients redo surgery was done after six months. Two patients required staged procedure and in three permanent perineal urethrostomy were made due to poor urethral condition, all in older patients. These five patients were excluded from the study. Anastomotic narrowing was most common finding. Redo urethroplasty was successful in all patients.Buccal mucosa as a free graft provides excellent functional outcome in anterior urethral stricture

    Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

    Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Five insights from the Global Burden of Disease Study 2019

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    The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a rules-based synthesis of the available evidence on levels and trends in health outcomes, a diverse set of risk factors, and health system responses. GBD 2019 covered 204 countries and territories, as well as first administrative level disaggregations for 22 countries, from 1990 to 2019. Because GBD is highly standardised and comprehensive, spanning both fatal and non-fatal outcomes, and uses a mutually exclusive and collectively exhaustive list of hierarchical disease and injury causes, the study provides a powerful basis for detailed and broad insights on global health trends and emerging challenges. GBD 2019 incorporates data from 281 586 sources and provides more than 3.5 billion estimates of health outcome and health system measures of interest for global, national, and subnational policy dialogue. All GBD estimates are publicly available and adhere to the Guidelines on Accurate and Transparent Health Estimate Reporting. From this vast amount of information, five key insights that are important for health, social, and economic development strategies have been distilled. These insights are subject to the many limitations outlined in each of the component GBD capstone papers.Peer reviewe
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