54 research outputs found

    Studying the effects of earthquakes near and far fault region on seismic behavior of dual frame equipped with viscous damper

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    The effects of strong earthquakes in the past years show that the acceleration of near fault earthquake, for having impact motion with long periods at the beginning of the record, “exerted” have significant differences with far-fault earthquakes. Adverse effects of such earthquakes increases by approaching the main time of period of structures to period of these earthquakes. Nowadays using energy dissipation systems, in order to reduce the vibrations of the structure has been very common. Such these energy dissipation systems can be noted viscose dampers that by having hysteresis loops of fat greatly increase energy loss in buildings. In this study, the number of dual-steel frames equipped with nonlinear viscous dampers and by applying records seismic near and far fault to the frames of 4, 6, 8 and 10 floors, behavior and response of these types of frames by nonlinear analysis and in Perform 3D software is evaluated

    Comparison between structural configurations designed by steel shear wall, moment resistant frame and X shape bracing systems

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    Nowadays, in order to increase construction of tall structures, the importance of choosing optimum systems, with a huge energy absorption capacity against wind and earthquake loads, has been widely considered. Since four decades ago, steel shear walls had been used as a stiff and high performance lateral system. This study is about the effect of concrete filled steel tubes (CFT) columns as vertical boundary elements of steel shear wall on seismic behavior of steel structures. Due to do this, three 10- storey steel structures, with similar plans and lateral load career systems of steel shear wall, coinciding X-bracing, and moderate steel frame were analyzed by means of non-linear, time-history method through SAP2000 software, and the results of roof displacement of them were compared with each other. Also after validating a two-storey, single-span frame sample with steel shear walls and CFT columns, 3 single-storey structures were analyzed by means of hysteresis and pushover, through ABAQUS software. The results of this study showed that a shear wall system presents suitable stiffness, resistance and ductility in comparison with other lateral bearing systems.Peer ReviewedPostprint (published version

    Investigating the Effect of Viscous Damper on Seismic Behavior of Steel Dual Frames with Divergent Bracing Affected by Near and Far Fields Earthquake to Fault

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    Current study is sought to study the effect of linear and nonlinear liquid viscous dampers on steel frames having dual systems of bending frame and divergent bracing. These frames were first designed according to regulations of Iran’s 2800 standard and tenth chapter of national regulations of construction (planning and performing steel construction) through equivalent static method then frames were modelled again in non-linear analysis software and time history non-linear analyses were done on them with installing viscous dampers on these frames using recorded near and far faults. In this study the effect of viscous dampers will be investigated on seismic behaviour of mentioned frames and results will be proposed in form of maximum graphs of relative displacements, stories lateral displacements, base shear maximum, waste energy graphs and dampers’ force-displacements. All non-linear analyses have been done in PERFORM-3D software

    Worldwide incidence and mortality of ovarian cancer and Human Development Index (HDI): GLOBOCAN sources and methods 2018

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    Ovarian cancer is the seventh most common cancer among women, accounting for about 4% of all cancers associated with women. This is a descriptive cross-sectional study based on extraction of cancer incidence data and cancer mortality rates from the Global Cancer Data in 2018. The incidence and mortality rates and ovarian cancer distribution maps were drawn for World countries. To analyze data, correlation test and regression tests were used to evaluate the correlation between its incidence and mortality with HDI. The results showed that there was a positive and significant correlation between ovarian cancer incidence (R = 0.409, P <0.0001) and mortality (R = 0.193, P <0.05) with HDI. The results showed that there was a positive and significant correlation between incidence with GNI ,MYS ,LEB and EYS ( P <0.0001). The results also demonstrated that there was a positive and significant correlation between mortality and GNI, MYS, LEB and EYS ( P <0.05).The linear regression model showed that a higher MYS [B = 0.2, CI95%: (- 0.03,0.5)] significantly increased the incidence of ovarian cancer and increased MYS [B = 0.2, CI95% (0.03, 0.4)] increased mortality. Given the positive and significant correlation between ovarian cancer incidence and mortality with HDI, attention to risk factors in these countries can be effective in curbing its incidence and mortality

    Using Theory CMOS Active Inductors in Low Noise Amplifier

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    ABSTRACT In this paper we present LNA with active inductor circuits are employed to assess their suitability for providing a tuning function in HEMT circuits. Comparisonof measurement and simulation ofan active inductor shows the high quality factor. Simulations ofthe low noise amplifier show the advantages of active inductorswith similar performance even in regard to the nois

    Comparing Efficiency of Rice Washing and Soaking Processes in Reducing the Amount of Aflatoxin B1

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    Contamination of some agricultural products by mycotoxins has exposed the human and animal health to serious concerns. Aflatoxin B1 is the most toxic type of aflatoxins, which is of the highest amount in different foods, including rice, among various types of aflatoxins. The present study was aimed to evaluate the amount of this toxicant in the consuming rice in Yazd city and investigate the effect of rice washing and soaking process on reduction of the mean concentration of aflatoxin B1. The present study was a descriptive-analytical one, in which 36 rice samples (18 domestic types and 18 foreign types of rice) were randomly selected from the rice distribution centers in Yazd city. The Standard No.6872 of the Institute of Standards & Industrial Research of Iran (ISIRI) was used for measuring the amount of aflatoxin B and G toxicants using HPLC (high pressure or performance liquid chromatography) method and purifying by immune affinity column. Analysis of the collected data was performed using SPSS-22 statistical software as well as the statistical methods of one-way ANOVA and Tukey HSD. The mean concentration of aflatoxin B1 in domestic and imported rice was measured equal to 1.461 and 0.508ng/g, respectively. The contamination rate in the imported rice was lower than that in the domestic one, while there was no significant relationship between them (p≥0.166); furthermore, the effect of soaking process on reduction of the toxicant amount in one and ten hours of soaking was statistically insignificant. There was no significant relationship between the effect of a single time of washing and reduction of the amount of toxicant; however, in case of three and five times of washing, the amount of toxicant exhibited a reduction of 68.2% and 98.7%, respectively, which was statistically significant (

    The emerging role of regulatory cell-based therapy in autoimmune disease

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    Autoimmune disease, caused by unwanted immune responses to self-antigens, affects millions of people each year and poses a great social and economic burden to individuals and communities. In the course of autoimmune disorders, including rheumatoid arthritis, systemic lupus erythematosus, type 1 diabetes mellitus, and multiple sclerosis, disturbances in the balance between the immune response against harmful agents and tolerance towards self-antigens lead to an immune response against self-tissues. In recent years, various regulatory immune cells have been identified. Disruptions in the quality, quantity, and function of these cells have been implicated in autoimmune disease development. Therefore, targeting or engineering these cells is a promising therapeutic for different autoimmune diseases. Regulatory T cells, regulatory B cells, regulatory dendritic cells, myeloid suppressor cells, and some subsets of innate lymphoid cells are arising as important players among this class of cells. Here, we review the roles of each suppressive cell type in the immune system during homeostasis and in the development of autoimmunity. Moreover, we discuss the current and future therapeutic potential of each one of these cell types for autoimmune diseases

    Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

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    BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed
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