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Glass and Mineral Chemistry of Northern Central Indian Ridge Basalts:Compositional Diversity and Petrogenetic Significance

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1122-1135页

作者： Dwijesh RAY Ranadip BANERJEE Sridhar D IYER Basavaraju BASAVALINGU subir MUKHOPADHYAY4 National Centre for Antarctic and Ocean Research National Institute of Oceanography CSIR Department of Studies in Geology University of Mysore Department of Geological Sciences Jadavpur University

The glass and mineral chemistry of basaits examined from the northern central Indian ridge （NCIR） provides an insight into magma genesis around the vicinity of two transform faults： Vityaz （VT） and Vema （VM）. The studied mid-ocean ridge basalts （MORBs） from the outer ridge flank （VT area） and a near-ridge seamount （VM area） reveal that they are moderately phyric plagioclase basalts composed of plagioclase （phenocryst [An60-90] and groundmass [An35-79]）, olivine （Fo81-88）, diopside （Wo45-51, En25-37, Fs14-24）, and titanomagnetite （FeOt -63.75 wt% and TiO2 -22.69 wt%）. The wholerock composition of these basalts has similar Mg# [mole Mg/mole（Mg＋Fe2＋）] （VT basalt： -0.56-0.58; VM basalt： -0.57）, but differ in their total alkali content （VT basalt： -2.65; VM basalt： -3.24）. The bulk composition of the magma was gradually depleted in MgO and enriched in FeOt, TiO2, P2O5, and Na2O with progressive fractionation, the basalts were gradually enriched in Y and Zr and depleted in Ni and Cr. In addition, the ∑REE of magma also increased with fractionation, without any change in the （La/ Yb）N value. Glass from the VM seamount shows more fractionated characters （Mg#： 0.56-0.57） compared to the outer ridge flank lava of the VT area （Mg#： 0.63-0.65）. This study concludes that present basalts experienced low-pressure crystallization at a relatively shallow depth. The geochemical changes in the NCIR magmas resulted from fractional crystallization at a shallow depth. As a consequence, spinel was the first mineral to crystallize at a pressure 〉10 kbar, followed by Fe-rich olivine at 〈10 kbar pressure.

关键词： mineral chemistry fractional crystallization petrogenesis northern central Indian ridge

Environmental and rock magnetic studies of rapid fluctuations of Asian summer monsoon during the last interglacial maximum(MIS 5e)

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Chinese Science Bulletin 1999年第10期44卷 952-954页

作者： Xiaomin Fang subir K. Banerjee Jijun Li Xuerong Dai Donghong Guan Lanzhou Univ Dept Geog Lanzhou 730000 Peoples R China Univ Minnesota Dept Geol & Geophys Inst Rock Magnetism Minneapolis MN 55455 USA

A systematic environmental rock magnetic study of a century-millennial scale loesspaleosol sequence of the last interglacial in the Jiuzhoutai well section, Lanzhou, on the western Loess Plateau demonstrates that Asian summer monsoon experienced fast and large oscillations manifesting as three peaks and two valleys lasling about 1—2 ka. Valley 4 with a central age of 120.5 ka is the most evident, suggesting that summer monsoon was weakened nearly to a level in glaciations. This indicates that summer monsoon has a nature of instability in centurymillennial scale change in the last interglacial.

关键词： environment rock magnetism last interglacial summer monsoon.

Large-signal characterization of DDR silicon IMPATTs operating in millimeter-wave and terahertz regime

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Journal of Semiconductors 2013年第10期34卷 46-53页

作者： Aritra Acharyya Jit Chakraborty Kausik Das subir Datta Pritam De Suranjana Banerjee J.P.Banerjee Institute of Radio Physics and Electronics University of Calcutta92APC RoadKolkata 700009India Supreme Knowledge Foundation Group of Institutions Sir J.C.Bose School of Engineering1Khan RoadMankunduHooghlyWest Bengal 712139India Academy of Technology West Bengal University of TechnologyAdisaptagramHooghly 712121West BengalIndia

The authors have carried out the large-signal characterization ofsilicon-based double-drift region （DDR） impact avalanche transit time （IMPATT） devices designed to operate up to 0.5 THz using a large-signal simulation method developed by the authors based on non-sinusoidal voltage excitation. The effect of band-to-band tunneling as well as parasitic series resistance on the large-signal properties of DDR Si IMPATTs have also been studied at different mm-wave and THz frequencies. Large-signal simulation results show that DDR Si IMPATT is capable of delivering peak RF power of 633.69 mW with 7.95% conversion efficiency at 94 GHz for 50% voltage modulation, whereas peak RF power output and efficiency fall to 81.08 mW and 2.01% respectively at 0.5 THz for same voltage modulation. The simulation results are compared with the experimental results and are found to be in close agreement.

关键词： band to band tunneling DDR silicon IMPATTs large-signal simulation millimeter-wave series resistance terahertz regime

Palaeogeography, palaeohydraulics and palaeoclimate of the Mio-Pliocene Siwalik Group, eastern India

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Journal of Palaeogeography 2014年第3期3卷 270-296页

作者： Sunipa Mandal subir Sarkar Nivedita Chakraborty Pradip K.Bose Department of Geology Asutosh College Department of Geological Sciences Jadavpur University

South-southwestward palaeocurrent swerved to east-southeast and then broadly to southeast over the transition from alluvial fan to axial channel and then to the flood plain in the Mio-Pliocene foreland system within which the Siwalik Group depositd in Darjeel- ing-Jalpaiguri Districts, eastern India. Palaeocurrent pattern is found to be multi-modal on the fans, virtually unimodal on the axial channel zone and again multi-modal, more profoundly, on the flood plain. Coarse siliciclastic mass-flows were progressively eliminated and gave way to predominant bed-load transport downfan and the axial river, and then to suspensionload dominance in fine siliciclastics on the flood plain. Distal flood plain lacustrine sediment included most of the coals and the entire bulk of the dolomitic limestone. Further resolution in palaeogeography within the frame of aforementioned foursome facies associations is elicited in twenty-six distinctive facies altogether. Critical evaluation of chemical indices （CIA, CIW, ICV, PIA, as well as Rb/Sr ratio） for weathering and depleted （3180 values indicate a high precipitation rate. The contention is further corroborated by the high discharge rate calculated from cross-set thicknesses within the main channel deposits. Reconciliation of various relevant data sets collected or calculated from all known worksites along the entire 2000 km-Iong exposure belt of the Siwaliks along the Himalayan foothills reveal confluence of two tributaries, one from the west and the other from the east, close to the present study area before escaping onto the Indian plains. Channel parameters, channel-belt width and discharge thus attained maxima in the present study area. The precipitation rate and temperature increased eastward overall as a prelude to the modern trend in this regard. 13C enrichment indicates that the transition from C3 to C4 vegetation had already set in.

关键词： Mio-Pliocene Siwalik Group Darjeeling Himalayas spatial variation axialriver reconstruction vegetation

A Scalable Key Management Scheme for Secure Multicasting over Bluetooth Scatternets

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China Communications 2008年第2期5卷 25-33页

作者： subir Biswas Syed Rehan Afzal Jong-bin Koh Mustafa Hasan Gunhee Lee Dong-kyoo Kim Graduate School of Information and Communication Ajou University

Secure multicasting is one of the major requirementsfor today’s communication *** for any kindof secure communication,a key-distribution schemeis the most sensible *** a highly promising,low-cost,and emerging wireless technology,Bluetooth has key distribution supports for securemulticasting over its unit one-hop network,*** core specification[1]defines basic securityprotocols for key generation,encryption,andauthentication for intra-piconet ***,not much attention has been paid so far on securingmulticasting over the Bluetooth Scatternet;nevertheless,multicasting is quite a sensible aspectof modern communication *** in this paper,we extend the piconets key distribution scheme topresent a new key management scheme for securemulticasting over Bluetooth *** keymanagement scheme is compatible to the currentBluetooth architecture design as we rely onBluetooth’s existing security algorithms to proposeour resolution.

关键词： Bluetooth Piconet Scattemet Master node Master key

Siliciclastic-carbonate mixing modes in the river-mouth bar palaeogeography of the Upper Cretaceous Garudamangalam Sandstone(Ariyalur, India)

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Journal of Palaeogeography 2014年第3期3卷 233-256页

作者： subir Sarkar Nivedita Chakraborty Anudeb Mandal Santanu Banerjee Pradip K.Bose Department of Geological Sciences Jadavpur University Department of Earth Sciences Indian Institute of Technology Bombay Powai Mumbai-400076 India

Mixed siliciclastic-carbonate rocks constitute the Upper Cretaceous Garuda- mangalam Sandstone Formation, Ariyalur （India）, and offer an opportunity to look into the broad spectrum of mixing of compositionally and genetically different components. The palaeogeographic reconstruction indicates that deposition in the nearshore zone differed strongly in energy and active processes operatives due to the presence of a shore-parallel river-mouth bar. The western wing of the Mississippi bird-foot delta is considered to be a present-day analogon. Facies analysis in combination with petrography clearly shows the variability in palaeoenvironmental characteristics, both biogenic and non-biogenic. It also indicates dia- genetic uptake of carbonate that filled empty spaces and actively replaced original compo- nents. Chemical staining followed by limited application of cathodoluminescence and energy dispersive X-ray analysis （EDAX） hint at intricacies in mixing arising from the compositional variations in the carbonate components. A model of siliciclastic-carbonate sediment mixing, including both the depositional and diagenetic developments, is presented; it is aimed at generating a better overview of, and a deeper insight into, the physical and chemical mechanisms involved.

关键词： mixed siliciciastic-carbonate succession Garudamangalam Sandstone Formation Upper Cretaceous river-mouth bar India

Significant increase in HBV, HCV, HIV and syphilis infections among blood donors in West Bengal, Eastern India 2004-2005: Exploratory screening reveals high frequency of occult HBV infection

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World Journal of Gastroenterology 2007年第27期13卷 3730-3733页

作者： Prasun Bhattacharya Partha Kumar Chandra Sibnarayan Datta Arup Banerjee Subhashish Chakraborty Krishnan Rajendran subir Kumar Basu Sujit Kumar Bhattacharya Runu Chakravarty Institute of Blood Transfusion Medicine and Immunohematology Kolkata India ICMR Virus Unit Kolkata India National Institute of Cholera and Enteric Diseases Kolkata India

AIM: To evaluate the prevalence of markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) and human immunodeficiency virus (HIV) among blood donors in Kolkata, Eastern India for two consecutive years and to conduct a pilot study to explore the presence of HBV DNA among hepatitis B surface antigen (HBsAg) negative but anti-HBc positive blood donors. METHODS: Seroprevalence of HBsAg, anti-HCV and anti-HIV was studied among 113 051 and 106 695 voluntary blood donors screened in 2004 and 2005, respectively. Moreover, a pilot study on 1027 HBsAg negative donors was carried out for evaluating the presence of HBV DNA by PCR on HBsAg negative/anti- HBc positive donors. RESULTS: A statistically significant increase in the prevalence of HBV (1448 vs 1768, P < 0.001), HIV (262 vs 374, P < 0.001), HCV (314 vs 372, P = 0.003) and syphilis (772 vs 853, P = 0.001) infections was noted among blood donors of Kolkata West Bengal in 2005 as compared to 2004. Moreover, the exploratory study on 1027 HBsAg negative donors revealed that 188 (18.3%)of them were anti-HBc positive out of which 21% were positive for HBV DNA. CONCLUSION: The findings of this study underscore the significantly increasing endemicity of hepatitis viruses, syphilis and HIV among the voluntary blood donors of our community. The pilot study indicates a high rate of prevalence of HBV DNA among HBsAg negative/anti-HBc positive donors and thus emphasizes the need for a more sensitive and stringent screening algorithm for blood donations.

关键词： Hepatitis B virus Human immunodeficiency virus Hepatitis C virus Blood donation Occult HBV infection

YOGIC WAY-A HARMONY OF PUBLIC HEALTH PREPAREDNESS AND MANKIND

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YOGIC WAY-A HARMONY OF PUBLIC HEALTH PREPAREDNESS AND MANKIN...

Role of T cell death in maintaining immune tolerance during persistent viral hepatitis

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： subir Debnath Malaviya National Institute of Technology Jaipur-302017(Rajasthan)India

Health is a state of complete physical,mental and social well-being and not merely the absence of disease or *** has been declared a fundamental human *** implies that the state has a responsibility for the health of its people in equal *** governments all over the world are striving to expand and improve their health care services. Health is influenced by a number of factors such as adequate food,housing,basic sanitation, healthy lifestyles,protection against environmental hazards and communicable *** the government should embraces a multitude of services provided to individuals or communities for the purpose of promoting,maintaining,monitoring,or restoring health.

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World Journal of Gastroenterology 2013年第12期19卷 1877-1889页

作者： Juan Ramón Larrubia Megha Uttam Lokhande Silvia García-Garzón Joaquín Miquel Dolores subirá Eduardo Sanz-de-Villalobos Translational Hepatology Unit Guadalajara University Hospital University of Alcalá

Virus-specific T cells play an important role in the resolution of hepatic infection. However, during chronic hepatitis infection these cells lack their effector functions and fail to control the virus. Hepatitis B virus and hepatitis C virus have developed several mechanisms to generate immune tolerance. One of these strategies is the depletion of virus-specific T cells by apoptosis. The immunotolerogenic liver has unique property to retain and activate na ve T cell to avoid the over reactivation of immune response against antigens which is exploited by hepatotropic viruses to persist. The deletion of the virus-specific T cells occurs by intrinsic (passive) apoptotic mechanism. The pro-apoptotic molecule Bcl-2 interacting mediator (Bim) has attracted increasing attention as a pivotal involvement in apoptosis, as a regulator of tissue homeostasis and an enhancer for the viral persistence. Here, we reviewed our current knowledge on the evidence showing critical role of Bim in viral-specific T cell death by apoptotic pathways and helps in the immune tolerance.

关键词： T cell death Specific cytotoxic T lymphocytes Hepatitis C virus immune tolerance Apoptosis Bcl-2 interacting mediator Liver tolerance Apoptotic pathways Viral hepatitis