19 research outputs found
Response function analysis of excited-state kinetic energy functional constructed by splitting k-space
Over the past decade, fundamentals of time independent density functional
theory for excited state have been established. However, construction of the
corresponding energy functionals for excited states remains a challenging
problem. We have developed a method for constructing functionals for excited
states by splitting k-space according to the occupation of orbitals. In this
paper we first show the accuracy of kinetic energy functional thus obtained. We
then perform a response function analysis of the kinetic energy functional
proposed by us and show why method of splitting the k-space could be the method
of choice for construction of energy functionals for excited states.Comment: 11 page
Culture-independent real-time PCR reveals extensive polymicrobial infections in hospitalized diarrhoea cases in Kolkata, India
Culture-independent identification of diarrhoeal aetiological agents was performed using DNA harvested from diarrhoeal stool specimens with SYBR-Green-based real-time PCR targeting Vibrio cholerae, Vibrio parahaemolyticus, Campylobacter spp., Shigella spp. and three different pathotypes of diarrhoeagenic Escherichia coli. Conventional culture-dependent methods detected bacterial enteropathogens in 68 of 122 diarrhoeal stool specimens. Of 68 specimens, 59 (86.8%) had a single pathogen and the remaining nine (13.2%) had polymicrobial infections with multiple pathogens. Re-analysis of the 68 specimens by culture-independent real-time PCR methods showed that 25 (36.8%) specimens contained single pathogen and 43 (63.2%) specimens contained mixed infections with multiple pathogens. The prevalence of such high levels of polymicrobial infections would not have been detected without using real-time PCR. Culture-dependent analysis assigned 54 of the 122 selected archived specimens as 'no known aetiology'. However, re-analysis of these samples by real-time PCR showed the presence of single or multiple pathogens among 34 (63%) of these specimens. Estimation of relative pathogen load by real-time PCR in the stool specimens indicated that the inability of conventional culture-dependent methods to detect the pathogens was related to lower colony-forming units of the pathogen, as reflected by lower C(t) values. Detection of high levels of polymicrobial infection by real-time PCR indicates that in the settings like Kolkata and its surroundings, where cholera and other enteric diseases are endemic, the concept of one pathogen one disease might need to be re-evaluated
Inlet Hydraulics of Chilika Lagoon
137-144Inlet hydraulics of Chilika Lagoon is studied using various observed inlet parameters (tide, current and morphology) and computing parameters such as hydraulic radius, inlet impedance, Kingâs inlet frequency and friction, maximum channel velocity, phase lag and repletion coefficient during 2009 for spring and neap tide conditions. It is revealed that maximum water level variation in the lagoon occurs during May and is associated with wind âtide interaction in the absence of freshwater discharge. Results indicate ebb dominance of inlet during wet period (July to December) and flood dominance during dry period (February to May) of the lagoon. Period of maximum ebb current (July) coincides with the period of maximum fresh water discharge while period of maximum flood current (May) coincides with the period of maximum momentum input and percentage of sea distribution. Ebb dominance of the inlet is also revealed through computation and analysis of hydraulic parameters, primarily repletion values. Keeping in view the role of inlet hydraulics on the cotemporary phase of lagoon transformation, integration of inlet management into the overall ecosystem management of the lagoon is suggested
Neoarchean-mesoproterozoic mafic dyke swarms of the indian shield mapped using google earthâą images and arcgisâą, and links with large igneous provinces
We present dyke swarm maps generated using Google Earthâą images, ArcGISâą, field data, and available geochronological ages of Neoarchean-Mesoproterozoic (ranging in age from ~2.80 to ~1.10ĂÂ Ga) mafic dyke swarms and associated magmatic units of the different Archean cratons of the Indian shield which represent the plumbing system of Large Igneous Provinces (LIPs). The spatial and temporal distributions together with the trends of the dyke swarms provide important informations about geodynamics. Twenty four dyke swarms (17 have been precisely dated), mostly mafic in nature, have been mapped from the different cratons and named/re-named to best reflect their location, trend, distribution and distinction from other swarms. We have identified 14 distinct magmatic events during the Neoarchean-Mesoproterozoic in the Indian shield. These intraplate magmatic events (many of LIP scale) of the Indian shield and their matches with coeval LIPs on other crustal blocks suggest connections of the Indian shield within known supercontinents, such as Kenorland/Superia (~2.75â2.07ĂÂ Ga), Columbia/Nuna (1.90â1.38ĂÂ Ga), and Rodinia (1.20â0.72ĂÂ Ga). However, further detailed UâPb geochronology and associated paleomagnetism are required to come to any definite constraints on the position of the Indian cratons within these supercontinents
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Not AvailableMaintaining soil organic carbon (SOC) in arid ecosystem is important for soil productivity and restoration of deserted sandy soil in western plain of India. There is a need to understand how the cropping systems changes may alter SOC pools including total organic carbon (TOC), particulate organic C (POC), water soluble carbon (WSC), very labile C (VLC), labile C (LC), less labile C (LLC) and non-labile C (NLC) in arid climate. We selected seven major agricultural systems for this study viz., barren, fallow, barleyâfallow, mustardâmoth bean, chickpeaâgroundnut, wheatâgreen gram and wheatâpearl millet. Result revealed that conversion of sandy barren lands to agricultural systems significantly increased available nutrients and SOC pools. Among all studied cropping systems, the highest values of TOC (6.12 g kgâ1), POC (1.53 g kgâ1) and WSC (0.19 g kgâ1) were maintained in pearl milletâwheat system, while the lowest values of carbon pools observed in fallow and barren land. Strong relationships (P < 0.05) were exhibited between VLC and LC with available nutrients. The highest carbon management index (299) indicates that wheatâpearl millet system has greater soil quality for enhancing crop productivity, nutrient availability and carbon sequestration of arid soil.Not Availabl
Precambrian mafic dyke swarms in the Singhbhum craton (eastern India) and their links with dyke swarms of the eastern Dharwar craton (southern India)
Based on trend, cross-cutting relationships and U-Pb dating, Precambrian mafic dykes in the Singhbhum craton, earlier collectively identified as âNewer Dolerite Swarmâ have been separated into seven distinct swarms, which are thought to be the plumbing systems for Large Igneous Provinces (LIPs). These Singhbhum swarms range in age from âŒ2.80 Ga to âŒ1.76 Ga, and include the âŒ2.80 Ga NE-SW trending Keshargaria swarm, âŒ2.75â2.76 Ga NNE-SSW to NE-SW trending Ghatgaon swarm, the âŒ2.26 Ga NE-SW to ENE-WSW trending Kaptipada swarm (based on a new U-Pb ID-TIMS age 2256 ± 6 Ma), the âŒ1.77 Ga WNW-ESE trending Pipilia swarm, the early-Paleoproterozoic E-W to ENE-WSW trending Keonjhar swarm, the middle-Paleoproterozoic NW-SE to NNW-SSE trending Bhagamunda swarm, and the late-Paleoproterozoic N-S to NNE-SSW trending Barigaon swarm. Two of the Singhbhum swarms, the âŒ2.26 Ga Kaptipada and âŒ1.77 Ga Pipilia, are closely matched with the âŒ2.26â2.25 Ga Ippaguda-Dhiburahalli and âŒ1.79 Ga Pebbair swarms, respectively, of the eastern Dharwar craton. The correlations suggest that the Singhbhum and Dharwar cratons were close enough at these times to share two reconstructed LIPs, a 2.26â2.25 Ga Kaptipadaâ Ippaguda-Dhiburahalli LIP and a 1.79â1.77 Ga Pipilia-Pebbair LIP, and if so, both swarms must be present in the intervening Bastar craton (candidates are proposed). Also, the 2.76â2.75 Ga Ghatgaon swarm of the Singhbhum craton can be provisionally correlated with âŒ2.7 Ga Keshkal swarm of the Bastar craton. The 2.26â2.25 Ga KaptipadaâIppaguda-Dhiburahalli LIP of the Singhbhum-Bastar-Dharwar reconstruction has age matches in the Vestfold Hills of Antarctica (âŒ2.24 Ga dykes), the Kaapvaal craton (the âŒ2.25â2.23 Ga Hekpoort lavas) a