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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

Variations in bark thickness and sapwood density of Calophyllum inophyllum provenances in Australia and in Sri Lanka

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Journal of Forestry Research 2011年第3期22卷 399-402页

作者： subhash Hathurusingha Nanjappa Ashwath Centre for Plant and Water Science CQ University Bruce highway Rockhampton 4702 Australia

Sapwood density and bark thickness of Calophyllum inophyllum L. （a multipurpose durable timber species） were studied in various locations in Northern Australia and in Sri Lanka. Measurements were taken non-destructively by using core sampling and bark gauge. From each provenance, 4–15 mature trees having girth at breast height over bark （GBHOB） at 100–150 cm were selected on the basis of the population size. Significant （p0.05） hemispheric and provenance variations in bark thickness were found. Variations in the bark thickness are influenced by environmental variables. Variations in sapwood density were less pronounced compared to that of bark thickness. Variations in sapwood density are likely to be governed by genotypic variations.

关键词： bark thickness Calophyllum inophyllum provenance variations sapwood density

Variations in body melanisation, ovariole number and fecundity in highland and lowland populations of Drosophila melanogaster from the Indian subcontinent

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Insect Science 2008年第6期15卷 553-561页

作者： subhash Rajpurohit Ravi Parkash Seema Ramniwas Shama Singh Department of Biochemistry and Genetics Maharshi Dayanand University Rohtak 124001 India

We investigated geographical variations in three fitness-related traits （body melanisation, ovariole number and fecundity） in laboratory-reared offspring of 10 populations of Drosophila melanogaster. The populations were collected from adjacent lowland and highland localities （-80-100 km apart） in the tropical as well as subtropical regions （11.15-31.06°N） covering a linear distance about 3 000 kilometers from south to north on the Indian subcontinent. Persistence of within- as well as between-population differences at 21 ℃ suggest that observed variations in fitness-related traits have a genetic basis. Populations from higher altitudes showed consistently higher trait values （1.4-fold increase） as compared with their corresponding lowland populations. By contrast, latitudinal variations were about two-fold higher across the entire continent. Along latitude as well as altitude, population means showed higher correlation values （r 〉 0.98） between all the three fitness traits. However, on the basis of within-population analysis （assorted darker and lighter flies）, changes in body melanisation were significantly correlated with fecundity but not with ovariole number. Thus, analysis of within-population trait variability should be preferred as compared with data on population means for adaptive significance of fitness-related traits. In the present study, the role of climatic selection is evident from regression analysis with changes in annual average temperature of the sites of origin of populations along latitude as well as altitude.

关键词： altitude body melanisation Drosophila melanogaster fecundity latitude ovariole number

Calophyllum inophyllum: recalcitrant or intermediate seed?

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Journal of Forestry Research 2012年第1期23卷 103-107页

作者： subhash Hathurusingha Nanjappa Ashwath Centre for Plant and Water Science CQ University Rockhampton 4702 Australia

We studied seed storage behaviour of a multipurpose tree Calophyllum inophyllum （Clusiaseae）. Seeds were collected at Roslyn bay （2307′60＂ S, 150°43′60＂ E） Central Queensland. Seed drying and desieeation tolerance tests were carried out according to International Seed Testing Association （ISTA） rules. We found C. inophyllum seeds to be recalcitrant and vulnerable to chilling injury, hence, unsuited for cold storage. C. inophyllum seeds maintained their viability for an appreciable period （〉 8 months） if stored in wanner environments.

关键词： Calophyllum inophyllum germination moisture content recalcitrant storage longevity seed storage behaviour

Temporal variation of solar flare index during solar cycles 21–24

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Research in Astronomy and Astrophysics 2021年第3期21卷 21-33页

作者： Soumya Roy Amrita Prasad subhash Chandra Panja Sankar Narayan Patra Department of Applied Electronics and Instrumentation Engineering Haldia Institute of TechnologyHaldiaMidnapore(E)-721657West BengalIndia Department of Mechanical Engineering Jadavpur UniversityKolkata-700032West BengalIndia Department of Instrumentation and Electronics Engineering Jadavpur UniversityKolkata-700106West BengalIndia

The present investigation attempts to quantify the temporal variation of Solar Flare Index(SFI)with other activity indices during solar cycles 21-24 by using different techniques such as linear regression,correlation,cross-correlation with phase lag-lead,*** Solar Activity Indices(SAI)considered in this present study are Sunspot Number(SSN),10.7 cm Solar Radio Flux(F10.7),Coronal Index(CI)and MgⅡCore-to-Wing Ratio(MgⅡ).The maximum cycle amplitude of SFI and considered SAI has a decreasing trend from solar cycle 22,and cycle 24 is the weakest solar cycle among all other *** SFI with SSN,F10.7,CI and MgⅡshows hysteresis during all cycles except for solar cycle 22 where both paths for ascending and descending phases are intercepting each other,thereby representing a phase reversal.A positive hysteresis circulation exists between SFI and considered SAI during solar cycles 22 and 23,whereas a negative circulation exists in cycles 21 and *** has a high positive correlation with coefficient values of 0.92,0.94,0.84 and 0.81 for SSN,F10.7,CI and MgⅡ*** to crosscorrelation analysis,SFI has a phase lag with considered SAI during an odd-number solar cycle(solar cycles21 and 23)but no phase lag/lead during an even-numbered solar cycle(solar cycles 22 and 24).However,the entire smoothed monthly average SFI data indicate an in-phase relationship with SSN,F10.7 and MgⅡ,and a one-month phase lag with *** presence of those above characteristics strongly confirms the outcomes of different research work with various solar indices and the highest correlation exists between SFI and SSN as well as F10.7 which establishes that SFI may be considered as one of the prime activity indices to interpret the characteristics of the Sun’s active region as well as for more accurate short-range or long-range forecasting of solar events.

关键词： Methods:data analysis Methods:statistical Sun:activity Sun:flares Sun:general

Role of CYP2E1 gene polymorphisms association with hepatitis risk in Northeast India

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World Journal of Gastroenterology 2010年第38期16卷 4800-4808页

作者： Manab Deka Moumita Bose Bharati Baruah Purabi Deka Bose subhash Medhi Sujoy Bose Anjan Saikia Premashish Kar subhash Medhi Sujoy Bose Department of Biotechnology Gauhati University Department of Medicine Maulana Azad Medical College Medical and Gastroenterology Unit Central Hospital N.F.Railway MaligaonGuwahati-781011India

AIM:To investigate hepatitis virus, genetic and environmental factors, and their interactions in predisposing patients to liver diseases in Northeast India. METHODS:A total of 104 jaundice patients and 124 community controls were included. Serological analysis was performed by routine enzyme-linked immunosorbent assay, and nucleic acid testing for hepatitis viruses was done by polymerase chain reaction (PCR), followed by PCR direct sequencing for viral genotyping. Cytochrome P450 2E1 (CYP2E1) polymorphism was studied by PCR-restriction fragment length polymorphism. Nitrite and volatile nitrosamines in indigenous foods consumed routinely by the Northeast Indian ethnic population were estimated by Griess’s reagent and GC-MS, ***: Hepatitis A virus (HAV) infection was predominantly prevalent (36.5%) in our cohort, followed by hepatitis B virus (HBV), hepatitis E virus (HEV) andhepatitis C virus. HBV genotype D and HEV genotype 1 were the most dominant. CYP2E1 c1/c2 genotype frequency was comparatively higher in alcoholic (P<0.0001,OR =30.5) and cryptogenic (P=0.014, OR=8.714) patients, and was associated with significantly higher hepatitis risk (P=0.0.007,OR=6.489). Mutant C allele of Cyp2E1 DraⅠ frequency was comparatively higher in HAV (P=0.006), alcoholic (P =0.003) and cryptogenic (P=0.014) cases, and was associated with overall hepatitis risk (P=0.026, OR=5.083). Indigenous foods, Gundruk, Kharoli, betel leaf and nuts were found to have the highest nitrite content. CONCLUSION: Apart from viral factors, CYP2E1 polymorphism might be associated with increased risk of liver diseases in Northeast India. Indigenous foods that contain nitrite and nitrosamine might be an associated risk factor.

关键词： Viral hepatitis Cytochrome P450 2E1 Gene polymorphism Nitrites Nitrosamines

Hedge fund replication using strategy specific factors

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Financial Innovation 2019年第1期5卷 179-197页

作者： Sujit subhash David Enke Laboratory for Investment and Financial Engineering Department of Engineering Management and Systems EngineeringMissouri University of Science and TechnologyRollaMO 65409-0370USA

Hedge funds have traditionally served wealthy individuals and institutional investors with the promise of delivering protection of capital and uncorrelated positive returns irrespective of market direction,allowing them to better manage portfolio ***,the financial crisis of 2008 has heightened investor sensitivity to the high fees,illiquidity,lack of transparency,and lockup periods typically associated with hedge *** fund replication products,or clones,seek to answer these challenges by providing daily liquidity,transparency,and immediate exposure to a desired hedge fund ***,although lowering cost and adding simplicity by using a common set of factors,traditional replication products might offer lower risk-reward performance compared to hedge *** research explores hedge fund replication further by examining the importance of constructing clones with specific factors relevant to each hedge fund strategy,and then compares the strategy specific clone risk and reward performance against both actual hedge fund performance and hedge fund clones constructed using a more general set of common *** shows that using strategy specific factors to replicate common hedge fund strategies can offer superior risk-reward performance compared to previous general model clones.

关键词： Hedge funds Hedge fund replication Regression Trading strategies Strategy specific factors

Decadal trends in precipitable water vapor over the Indus River Basin using ERA5 reanalysis data

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Journal of Mountain Science 2023年第10期20卷 2928-2945页

作者： Seema RANI Jyotsna SINGH subhash SINGH Purushottam TIWARI Suraj MAL Department of Geography Institute of ScienceBanaras Hindu UniversityUttar Pradesh 221005India Department of Geography Shaheed Bhagat Singh CollegeUniversity of DelhiNew Delhi 110017India Center for the Study of Regional Development Jawaharlal Nehru UniversityNew DelhiDelhi 11oo6zIndia

Precipitable Water Vapor(PWV)constitutes a pivotal parameter within the domains of atmospheric science,and remote sensing due to its profound influence on Earth’s climate dynamics and weather *** exerts a significant impact on atmospheric stability absorption and emission of radiation,thus engendering alterations in the Earth’s radiative *** such,precise quantification of PWV holds the potential to enhance weather prognostication and fortify preparedness against severe meteorological *** study aimed to elucidate the spatial and temporal changes in seasonal and annual PWV across the Indus River Basin and its sub-basins using ERA5 reanalysis *** present study used ERA5 PWV(entire atmospheric column),air temperature at 2 m(t2m)and 500 hPa(T_500hPa),evapotranspiration,and total cloud cover data from 1960 to *** Sen slope estimator and Mann-Kendall test were used for trend *** and multiple regression methods were used to understand the association of PWV with other *** findings have unveiled the highest increase in mean PWV during the monsoon(0.40 mm/decade),followed by premonsoon(0.37 mm/decade),post-monsoon(0.27 mm/decade),and winter(0.19 mm/decade)throughout the study ***,the mean PWV exhibited the most pronounced positive trend in the sub-basin Lower Indus(LI),followed by Panjnad(P),Kabul(K),and Upper Indus(UI)across all seasons,except *** PWV has also risen in the Indus basin and its sub-basins over the last six *** exhibits a consistent upward trend up to an elevation of 3500 m within the basin which is most pronounced during the monsoon season,followed by the *** escalating PWV within the basin is reasonably ascribed to increasing air temperatures,augmented evapotranspiration,and heightened cloud *** findings hold potential utility for pertinent authorities engaged in water resource management and planning.

关键词： Himalaya Precipitable Water Vapor Indus River Basin Atmosphere Climate Change ERA5 Reanalysis data

Dealing with detection error in site occupancy surveys: what can we do with a single survey?

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Journal of Plant Ecology 2012年第1期5卷 22-31页

作者： subhash R.Lele Monica Moreno Erin Bayne Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaCanada T6G 2G1 Department of Biological Sciences University of AlbertaEdmontonAlbertaCanada T6G 2G1

Aim Site occupancy probabilities of target species are commonly used in various ecological studies,*** monitor current status and trends in *** error introduces bias in the estimators of site *** methods for estimating occupancy probability in the presence of detection error use replicate *** methods assume population closure,*** site occupancy status remains constant across surveys,and independence between *** present an approach for estimating site occupancy probability in the presence of detection error that requires only a single survey and does not require assumption of population closure or *** place of the closure assumption,this method requires covariates that affect detection and *** Penalized maximum-likelihood method was used to estimate the *** of the parameters was checked using data *** boostrapping method was used for computing confidence *** Findings The single-survey approach facilitates analysis of historical datasets where replicate surveys are unavailable,situations where replicate surveys are expensive to conduct and when the assumptions of closure or independence are not *** method saves significant amounts of time,energy and money in ecological surveys without sacrificing statistical ***,we show that occupancy and habitat suitability are not synonymous and suggest a method to estimate habitat suitability using single-survey data.

关键词： abundance estimation biodiversity BBS closed population data cloning penalized likelihood species occurrence

GENERATION OF ASYMMETRIC F-v CHARACTERISTICS FOR SYMMETRIC MR DAMPERS

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 237-242页

作者： WANG Enrong YE Biaoming MA Xiaoqing SU Chunyi RAKHEJA subhash　 School of Electric ＆ Automation Engineering Nanjing Normal UniversityNanjing 210042 China Department of Mechanical ＆ Industrial Engineering Concordia UniversityMontreal H3G 1M8 Canada

An asymmetric damping force generation algorithm is originally proposed to yield the asymmetric force-velocity characteristics for the symmetric magneto-rheological （MR） dampers. The command current is formulated in an asymmetric manner to excite the symmetric MR dampers by employing the “on-off” control law in response to the direction of velocity, and a smooth modulation function is developed without phase shift to suppress strong transients in the damping forces caused by the current-switching discontinuity. The effectiveness of the proposed algorithm is evaluated by analyzing the dynamic responses of a quarter-vehicle suspension system with a symmetric MR-damper by modulating the command current into the asymmetric manner. The simulation results show that the proposed algorithm could achieve a better compromise between the conflicting requirements of the asymmetric damping force ratio and the force-velocity curve smoothness, and the asymmetric damping MR-suspension design can ideally improve the road holding and ride performances of vehicle motion. The proposed algorithm can be generally incorporated with a controller synthesis to realize an intelligent vehicle suspension design with the symmetric MR dampers.

关键词： Magneto-rheological (MR) fluids damper Asymmetric F-ν characteristics Smoothness Vehicle suspension