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Transition from radiatively inefficient to cooling dominated phase in two temperature accretion disks around black holes

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Research in Astronomy and Astrophysics 2009年第12期9卷 1331-1342页

作者： monika Sinha S.R.Rajesh Banibrata Mukhopadhyay Astronomy and Astrophysics Program Department of PhysicsIndian Institute of Science

We investigate the transition of a radiatively inefficient phase of a viscous two temperature accreting flow to a cooling dominated phase and vice versa around black holes. Based on a global sub-Keplerian accretion disk model in steady state, including explicit cooling processes self-consistently, we show that general advective accretion flow passes through various phases during its infall towards a black hole. Bremsstrahlung, syn- chrotron and inverse Comptonization of soft photons are considered as possible cooling mechanisms. Hence the flow governs a much lower electron temperature ～10^8 - 10^9.5 K compared to the hot protons of temperature ～10^10.2 - 10^11.8 K in the range of the accretion rate in Eddington units 0.01≤M≤ 100. Therefore, the solutions may potentially explain the hard X-rays and the γ-rays emitted from AGNs and X-ray binaries. We finally compare the solutions for two different regimes of viscosity and conclude that a weakly viscous flow is expected to be cooling dominated compared to its highly viscous counterpart which is radiatively inefficient. The flow is successfully able to reproduce the observed luminosities of the under-fed AGNs and quasars （e.g. Sgr A＊）, ultra-luminous X-ray sources （e.g. SS433）, as well as the highly luminous AGNs and ultra-luminous quasars （e.g. PKS 0743-67） at different combinations of the mass accretion rate and ratio of specific heats.

关键词： accretion accretion disk -- black hole physics -- hydrodynamics -- radia-tive transfer

Chemical characteristics of trace metals in PM10 and their concentrated weighted trajectory analysis at Central Delhi,India

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Journal of Environmental Sciences 2017年第5期29卷 184-196页

作者： Subhash Chandra monika J.Kulshrestha Ruchi Singh Nahar Singh CSIR-National Physical Laboratory New Delhi 110012 India. Academy of Scientific and Innovative Research (AcSIR) CSIR - National Physical Laboratory (CSIR-NPL) Campus New Delhi 110012 India Present address: Shriram Institute for Industrial Research Delhi 110007 India.

Trace metals associated with PM10 aerosols and their variation during day and nighttime as well as during different seasons have been studied for the year 2012. PCA analysis suggested5 PCs,which accounted for 86.8% cumulative variance. PC1 accounted for 30% with a significant loading of metals of anthropogenic origin,while PC2 showed 28% variance with the loading of metals of crustal origin. These trace metals showed seasonal distinct day and night time characteristics. The concentrations of Cu,Pb,and Cd were found to be higher during nighttime in all the seasons. Only Fe was observed with significantly higher mean concentrations during daytime of all seasons except monsoon. The highest mean values of Cu,Cd,Zn,and Pb during post-monsoon might be attributed to winds advection over the regions of waste/biomass burning and industrial activities in Punjab and Haryana ***,concentration weighted trajectory analysis suggested that metals of crustal origin were contributed by long-range transport while metals of anthropogenic and industrial activities were contributed by regional/local source regions.

关键词： Trace metals Potential source regions Backward trajectory Principal component analysis

Screening for nonalcoholic fatty liver disease-when,who and how?

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World Journal of Gastroenterology 2021年第35期27卷 5803-5821页

作者： Christoph G Dietrich monika Rau Andreas Geier Department of Internal Medicine Bethlehem Health CenterStolberg 52222Germany Department of Internal Medicine II University Hospital WürzburgWürzburg 97080Germany Department of Medicine II University Hospital WürzburgWürzburg 97080Germany

Nonalcoholic fatty liver disease(NAFLD)is becoming a frequent liver disease,especially in patients with metabolic syndrome and especially in Western *** of NAFLD comprise progressive fibrosis,cirrhosis and hepatocellular *** also represents an independent risk factor for cardiovascular disease,extrahepatic neoplasia and other organ damage,such as renal *** the epidemiological importance of the disease,new developments in specific treatment of the disease and the wide availability of noninvasive techniques in estimating steatosis and fibrosis,NAFLD should be subject to screening programs,at least in countries with a high prevalence of the *** review discusses prerequisites for screening,cost-effectiveness,current guideline recommendations,suitability of techniques for screening and propositions for the following questions:Who should be screened?Who should perform screening?How should screening be performed?It is time for a screening program in patients at risk for NAFLD.

关键词： Screening Nonalcoholic fatty liver disease Diabetes Liver fibrosis Cirrhosis

Synthesis and characterization of pyrimidines analogues as anti-Alzheimer's agents

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Journal of Chinese Pharmaceutical Sciences 2017年第11期26卷 834-846页

作者： Yadav Rakesh Maan monika Yadav Divya Department of Pharmacy Banasthali University Banasthali-304022 Rajasthan India

Pyrimidine derivatives have been reported as neuroprotective agents useful for the treatment of various neurodegenerative disorders. In the present study, several pyrimidine analogues have been evaluated as neuroprotective agents in Morris water maze model. It was observed that pyrimidine derivatives 8–17 considerably improve learning, memory, and movement deficits in animal models. Biochemical estimations of brain serum of treated animals revealed suppression of oxidative and nitrosative stress, acetylcholinesterase activity, and other parameters which leads to neurodegeneration of brain. Of all the pyrimidine derivatives, thiomorpholine derivative 8 and piperazine ethanol derivative 17 were found to be the most active neuroprotective agents and produced effects comparable to standard drug rivastigmine in terms of behavioral, biochemical, and molecular aspects.

关键词： Alzheimer's disease Neurodegeneration Pyrimidine derivatives Biochemical tests

Partition of bioactive components from red pitaya fruit(Hylocereus polyrhizus)peels into different fractions using supercritical fluid fractionation technology

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Food Bioscience 2023年第1期51卷 483-489页

作者： zer-Ran Yu Yih-Ming Weng Hsin-Yeh Lee Be-Jen Wang Superwell Biotechnology Corporation Taichung CityTaiwanROC Department of Food Science National Chiayi UniversityChiayiTaiwanROC

The pitaya peel powder was mixed with 50%ethanol solution at a ratio of 1:10(w/v)for 24 h to obtain the pitaya peel ethanol extract(E).The extract was further fractionated with supercritical carbon dioxide(SC-CO_(2))under the operating conditions:temperature 40℃ and pressure of 30,25,20 or 10 MPa into R,F1,F2 or F3 fractions,*** results confirmed SC-CO_(2)fractionation significantly influenced the distribution of phenolic compounds,polysaccharides and betalains in fractions and thus affected their physico-chemical *** compounds majorly distributed in F1;consequently,DPPH and ABTS radicals scavenging activities of F1 are higher than those of other *** IC_(50)values of DPPH and ABTS scavenging ability were 0.78 mg/mL and 0.69 mg/mL for F1 fraction,*** structure model analysis showed that the scavenging activities of the both free radicals were positively related to phenolic compounds and polysaccharide *** strong red-orange color spectrum of E was simultaneously fractionated into the red-orange color F1,the bright red color of F2 and F3 and the vivid orange color of R.

关键词： Red pitaya fruit Antioxidant activity Color characteristics Supercritical fluid fractionation

The case for gender considerate tobacco control policies in Albania

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Global Health Research and Policy 2020年第1期5卷 293-309页

作者： Harminder Guliani monikaÇule Department of Economics University of Regina3737 Wascana ParkwayReginaSKCanada

Background:Tobacco use is a serious health concern in *** the prevalence of tobacco smoking has traditionally been higher for men,the increasing prevalence of smoking for women is becoming a *** 2007 Tobacco Control policy mandated smoke-free indoor spaces,banned various forms of tobacco advertising,required written health warnings on packaging and levied excise taxes on cigarette *** smoking behavior varies among different demographic groups,each group’s response to a uniform policy will differ,blunting the effectiveness of these efforts as a *** study examines various socioeconomic,demographic and behavioral factors affecting both the likelihood and frequency of smoking in Albanian households in order to provide insights on targeting various populations more ***:The study utilizes data from Albanian 2008-09 and 2017-18 Demographic and Health Surveys consisting of adults aged 15-49 *** outcome variable includes respondents’current tobacco smoking behaviour and its *** exposure variables include respondents’sociodemographic and lifestyle *** use a two-level random intercept model with the two-stage residual inclusion estimation method to determine the association between outcome and exposure *** including a time variable,we capture the change in smoking behavior during the 2009-2018 *** also extend the analysis by assessing the differential influence of gender on the likelihood of smoking,both by income quintiles and ***:The results suggest that the likelihood of smoking decreased by 23%in 2017-18 compared to 2008-09,after controlling for various socioeconomic and demographic *** smoking is also found to be linked to alcohol consumption,with binge drinkers 59%more likely to smoke tobacco compared to moderate *** also found significant inter-quintile and inter-educational differences in smoking practices within each gender *** t

关键词： Albania Tobacco control Gender-based smoking behavior Multilevel analysis Two-stage residual inclusion

Grassland management intensity determines root development,soil structure,and their interrelationship:Results of a regional study of Leptosols in the Swabian Alps

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Grassland Research 2024年第2期3卷 171-186页

作者： Katrin Kuka monika Joschko Julius-Kühn-Institute(JKI) Institute for Plant and Soil ScienceBraunschweigGermany Leibniz Centre for Agricultural Landscape Research(ZALF) Experimental Infrastructure PlatformMünchebergGermany

Background:Soil structure is a key indicator of the functioning of soil processes in grasslands,which is influenced by site conditions and ***:In this study,we investigated soil structure and its relationship with root growth in 31 Leptosols under different grassland management intensities using X-ray microcomputed tomography.A close relationship between land use intensity,soil structure,and root growth was ***:Our results show that land use type affects root development and soil *** had more developed roots and more structured soils than meadows and mown ***,all pastures were unfertilized,while meadows and mown pastures had both fertilized and unfertilized *** no significant differences were found in the unfertilized plots,sample size was *** particular,fertilization negatively affected root growth and soil structure,resulting in significant differences between fertilized and unfertilized *** frequency also had an effect on soil physics,but to a much lesser extent than ***:Increased land use intensity,characterized by increased fertilization and more frequent mowing,reduces root growth and adversely affects soil ***,X-ray microcomputed tomography is a suitable method to investigate the relationship between soil structure and roots in the soil.

关键词： land use intensity meadow-mown pasture-pasture soil structure root-soil interaction X-ray microcomputed tomography

Did the Nationalist Government Manipulate the Chinese Bond Market？ A Quantitative Perspective on Short-Term Price Fluctuations of Domestic Government Bonds, 1932-1934

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Frontiers of History in China 2015年第1期10卷 126-144页

作者： Felix Boecking monika Scholz School of History Classics and Archaeology University of Edinburgh Edinburgh EH10 6AJUK Biophysical Sciences Graduate Program Institute for Biophysical Dynamics The University ofChicago Chicago IL 60615 USA

Based on a newly constructed set of data, this paper offers a quantitative perspective on the Nationalist Government＇s relations with China＇s domestic bond markets during the period 1932-34. For all the recent revisionist scholarship on the achievements of Nationalist state-building, the perception of the Nationalist elite as corrupt is still widely accepted. In order to demonstrate the empirical potential of quantitative financial history, this paper tests one particular assertion： that members of the Nationalist elite manipulated the issue price of domestic government bonds in order to enrich themselves and their associates. We test this by calculating two price data correlations： that of a first sample of government bonds, all of them issued before 1932, and that of a second sample of government bonds, which includes bonds issued during the period under review. The price fluctuations of the first sample are correlated with each other to a much higher degree than those of the second sample. This indicates that the prices of bonds in the first sample were reacting similarly to the same range of influences, while the bonds issued during the period under review and included in the second sample were displaying individual price fluctuations. One possible explanation for this is that members of the Nationalist elite enriched themselves or their associates by issuing domestic government bonds at artificially low prices. In sum, the article illustrates both the potential and the limitations of quantitative history： it allows us to test and dismiss a precisely formulated hypothesis about Nationalist corruption, but it is only one possible way in which statistical analysis can be applied and does not cover the wholeDid the Nationalist Government Manipulate the Chinese Bond Market？ realm of state practices

关键词： bond markets Guomindang financial history quantitative methods

TAXES AND SUSTAINABILITY

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Journal of Green Building 2007年第4期2卷 57-72页

作者： Annette Nellen monika Miles San JoséState University New America Foundation Labhart Miles Consulting Group Inc.

INTRODUCTION For several decades,we have periodically seen concern expressed about our environment and energy *** supply and cost of oil,the“hole”in the ozone layer,and various forms of pollution have at times also caught the attention of legislators and government officials who shape our *** *** of the Interior was created in 1949,and the first federal clean air act was enacted in *** 1970,President Nixon formed the Environmental Protection Agency(EPA),and the first celebration of Earth Day was April 22,*** have also enacted various laws over the years in efforts to reduce pollution.

关键词： pollution. ozone pollution