14 research outputs found

    A dermatopathic Juvenile Dermatomyositis; An Unexpected Case in Childhood

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    Abstract Juvenile dermatomyositis (JDM) is a rare idiopathic inflammatory disease which usually presents with skin rashes along with muscle weakness. We report a case of JDM in a 10- year-old girl with no skin manifestations.She was presented with progressive muscle weakness and fatigue. Further laboratory investigation along with a muscle biopsy confirmed the diagnosis of Adermathopathic Juvenile Dermatomyositis. The patient was treated with intravenous immunoglobulin, corticosteroids, methotrexate, hydroxychloroquine, pamidronate, and Rituximab.Following treatment, patients symptoms subsided and she gained normal muscular strength over the course of a year

    A comprehensive comparative investigation on solar heating and cooling technologies from a thermo-economic viewpoint—A dynamic simulation

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    © 2020 The Authors. Energy Science & Engineering published by the Society of Chemical Industry and John Wiley & Sons Ltd. The yearly thermo-economic performance is dynamically investigated for three solar heating and cooling systems: solar heating and absorption cooling (SHAC), solar heating and ejector cooling (SHEC), and heating and solar vapor compression cooling (HSVC). First, the effects of important design parameters on the thermo-economic performance of the systems to supply the heating and cooling loads of the building are evaluated. The systems are parametrically analyzed with the weather conditions of Tehran, Iran. The results show that the life cycle costs (LCC) of the SHAC and HSVC systems are alike and much lower than those of the SHEC system. The HSVC system exhibits the best performance from exergetic and solar fraction viewpoints. The comparative analysis shows that the energy efficiencies of the SHAC and SHEC systems are higher in colder climatic conditions. However, the collector efficiency of the HSVC system declines in colder climates, mainly due to the lower solar intensities relative to in hotter climates. Further, the solar fraction of the SHAC system is higher than the SHEC technology under all climatic conditions. Moreover, higher values of solar fractions are obtained under colder weather conditions for the SHEC and HSVC systems. The best economic performance is observed for the SHAC and HSVC technologies, having significantly lower LCCs than the SHEC system. These lower LCCs under colder climatic conditions are due to the lower cost of supplying the heating load compared to the cooling load. Furthermore, all systems exhibit enhanced exergetic performance in colder weather conditions. The yearly thermo-economic performance is dynamically investigated for three solar heating and cooling systems: SHAC, SHEC, and HSVC. In addition, the effects of important design parameters on the thermo-economic performance of the systems to supply the heating and cooling loads of the building are evaluated

    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

    Data-informed Delphi Survey for Harmonization of Methodological Parameter Space in fMRI Drug Cue Reactivity (FDCR) Tasks

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    This data-informed Delphi is aimed to harmonize parameters of fMRI Drug Cue Reactivity (FDCR) task design in studies that use FDCR as an outcome measure for interventions

    Primary spinal tumors and masses in children: a study of 37 cases

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    Abstract Objectives Spinal cord tumors are a rare diagnosis in children, mostly presented with unspecific symptoms which may pose a problem due to their possible malignancy and further complications. Yet there is little data regarding spinal cord lesions in our country.The aim of this study is to present a series of 37 cases of primary spinal tumors treated at the same institution and briefly review their pathology, symptoms and site of occurrence. Materials & Methods  37 cases of spinal cord tumors and masses were selected from March 2007 to 2017, excluding spinal dysraphism. Data regarding age, sex, clinical presentation, location of the mass, and pathology were retrospectively collected. Results Mean age at diagnosis was 5 years and 8 months (standard deviation: 4.1 years). 21 were male and 16 were female (male-to-female ratio: 1.31). Pathological findings were 9 Neuroepitheliomas (6 Neuroblastoma, 2 Ganglioneuroma, 1 Ganglioneuroblastoma/Ganglioneuroma), 4 Ependymomas, 3 Primitive Neuroectodermal Tumors, 3 Glial tumors, 4 Neurodevelopmental tumors, 3 Lymphomas, 1 Hemangiopericytoma and 1 Neurofibroma. 26 patients had Motor symptoms (74.2%), 14 had pain (40%), 6 showed sensory symptoms (16.6%) and 4 had urinary symptoms (11.4%). The most common location of occurrence was the lumbosacral region.  conclusion While differing in pathological composition and location of tumors in comparison to other papers, our study presents possible presentations and/or expected pathologies in pediatric spinal cord tumors. &nbsp

    Thermoeconomic analysis and multi-objective optimization of a novel trigeneration system consisting of kalina and humidificationdehumidification desalination cycles

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    Low-temperature geothermal heat sources have the highest share of geothermal energy in the world. Utilization of these heat sources for energy and freshwater generation can play an important role in meeting energy and freshwater demands. To do so, this study aims to propose a novel trigeneration cycle powered by low-temperature geothermal sources. The proposed system, which is an integration of Kalina and humidification-dehumidification (HDH) cycles, is used for the generation of electricity, heating, and freshwater. For the Kalina cycle, an evaporative condenser is used. It also acts as a humidifier and heater of the humidification-dehumidification desalination cycle, resulting in a reduction in the complexity of the trigeneration system. A comprehensive thermoeconomic analysis and multi-objective optimization of the new trigeneration system are performed. First, a detailed parametric study is carried out to investigate the effects of key design parameters, including turbine inlet pressure, condenser temperature, basic solution ammonia concentration, air mass flow rate and heat source temperature, on the thermoeconomic criteria. Then, a multiobjective optimization is conducted to determine the best design parameters, considering exergy and total cost rate as the objective functions. The optimal solution Pareto frontier indicates that the exergy efficiency and total cost rate vary in the range of 14.9-41.6% and 1.13-2.19 $/h, respectively. Analyses of the scattered distributions of design parameters reveal that lower heat source temperatures tend to optimize the objective functions. However, altering other design parameters has a significant effect on the trade-off between exergy efficiency and total cost rate

    Intelligent speed control of hybrid stepper motor considering model uncertainty using brain emotional learning

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    This paper presents an implementation of the brain emotional learning-based intelligent controller (BELBIC) for precise speed tracking of the hybrid stepper motor (HSM). Such a configuration is applicable where high resolution and accuracy is essential particularly in uncertain conditions. The proposed controller is a model-free controller independent of the model dynamics and variations that occur in a system. It is capable of autolearning to handle unforeseen disturbances. To evaluate the performance of the BELBIC controller in realistic conditions, the uncertainty of the system as a result of mechanical parameter variation and load torque disturbance is considered. To verify an excellent dynamic performance and the feasibility of the BELBIC, the system is simulated in MATLAB Simulink, and the results of the simulation are compared with an optimized proportional integral (PI) controller. The simulation results confirm the superior performance of the BELBIC for fast and precise speed response as well as its potential in dealing with nonlinearity and uncertainty handling as compared with that of the PI controller. The proposed controller is used in realistic applications, such as tunable-laser system and robot-assisted surgery
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