2009
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PublicationArticle Gregoryceras in the Oxfordian of Kachchh (India): Diverse eventful implications(Elsevier Masson SAS, 2009) Jai Krishna; Bindhyachal Pandey; Jai Ram OjhaThe Kachchh Oxfordian ammonoid stratigraphic record for over 150 years remained restricted largely to Early Oxfordian condensed oolitic facies in the relatively distal Mainland Kachchh. Recently, it has been enlarged with the discovery in 1994 of over 200 m-thick uncondensed Middle to Late Oxfordian succession at Kantkote in the proximal part of the basin. Apart from abundant Perisphinctinae and Mayaitinae, a 10 m-thick sediment interval in the lower half of the above succession yielded a few examples of Gregoryceras. The specimens are here identified as G. gr. devauxi Bert and Enay and in view of their association with Larcheria subschilli (Lee) are assigned to the Middle Oxfordian Subschilli Horizon of the Schilli Subzone. Gregoryceras distribution south of the equator in Kachchh, Chile, Mexico and Madagascar, all within 35-40° latitude marks the southern limit of its latitudinal expansion during the first order maximum flooding surface (MFS) of the Schilli Subzone of the Kachchh Toarcian-Hauterivian Sequence. The maximum ammonoid diversity, density and frequency of the Kachchh first order sequence coupled with dominance of mayaitins and perisphinctins suggest over 20 m depth in the Gregoryceras interval. Distinctly greater bathymetry in the 200 km distally away basinal part causes sediment starved situation, and explains the Middle Oxfordian to early Early Kimmeridgian submarine nondepositional hiatus in the Mainland Kachchh. © 2008 Elsevier Masson SAS. All rights reserved.PublicationArticle Petrology and geochemistry of diamondiferous Mesoproterozoic kimberlites from Wajrakarur kimberlite field, Eastern Dharwar craton, southern India: Genesis and constraints on mantle source regions(2009) N.V. Chalapathi Rao; Rajesh K. SrivastavaThe petrology and geochemistry of some new occurrences of Mesoproterozoic diamondiferous hypabyssal-facies kimberlites from the Chigicherla, Wajrakarur-Lattavaram and Kalyandurg clusters of the Wajrakarur kimberlite field (WKF), Eastern Dharwar craton (EDC), southern India, are reported. The kimberlites contain two generations of olivine, and multiple groundmass phases including phlogopite, spinel, calcite, dolomite, apatite, perovskite, apatite and rare titanite, and xenocrysts of eclogitic garnet and picro-ilmenite. Since many of the silicate minerals in these kimberlites have been subjected to carbonisation and alteration, the compositions of the groundmass oxide minerals play a crucial role in their characterisation and in understanding melt compositions. While there is no evidence for significant crustal contamination in these kimberlites, some limited effects of ilmenite entrainment are evident in samples from the Kalyandurg cluster. Geochemical studies reveal that the WKF kimberlites are less differentiated and more primitive than those from the Narayanpet kimberlite field (NKF), Eastern Dharwar craton. Highly fractionated (La/Yb = 108-145) chondrite-normalised distribution patterns with La abundances of 500-1,000 × chondrite and low heavy rare earth elements (HREE) abundances of 5-10 × chondrite are characteristic of these rocks. Metasomatism by percolating melts from the convecting mantle, rather than by subduction-related processes, is inferred to have occurred in their source regions based on incompatible element signatures. While the majority of the Eastern Dharwar craton kimberlites are similar to the Group I kimberlites of southern Africa in terms of petrology, geochemistry and Sr-Nd isotope systematics, others show the geochemical traits of Group II kimberlites or an overlap between Group I and II kimberlites. Rare earth element (REE)-based semi-quantitative forward modelling of batch melting of southern African Group I and II kimberlite source compositions involving a metasomatised garnet lherzolite and very low degrees of partial melting demonstrate that (1) WKF and NKF kimberlites display a relatively far greater range in the degree of melting than those from the on-craton occurrences from southern Africa and are similar to that of world-wide melilitites, (2) different degrees of partial melting of a common source cannot account for the genesis of all the EDC kimberlites, (3) multiple and highly heterogeneous kimberlite sources involve in the sub-continental lithospheric mantle (SCLM) in the Eastern Dharwar craton and (4) WKF and NKF kimberlites generation is a resultant of complex interplay between the heterogeneous sources and their different degrees of partial melting. These observations are consistent with the recent results obtained from inversion modelling of REE concentrations from EDC kimberlites in that both the forward as wells as inverse melting models necessitate a dominantly lithospheric, and not asthenospheric, mantle source regions. The invading metasomatic (enriching) melts percolating from the convecting (asthenosphere) mantle impart an OIB-like isotopic signature to the final melt products. © Springer-Verlag 2008.PublicationArticle Plant invasions along roads: A case study from central highlands, India(2009) Gyan P. Sharma; A.S. RaghubanshiRoad sides provide suitable conditions for the establishment and growth of non-native species. The phenomenon of non-native species spread through roads has further increased due to rapid anthropogenic developments. Here we intend to investigate the status of native and non-native species and how the species richness and diversity change in a perpendicular road transect across the three different road use types in the central highlands of India. Presence of 55 non-native species was recorded, of the total 71 species along the road sides. Non-native species richness significantly increased with increasing road use type. Although, the species diversity significantly decreased from road verges to the forest interior in all the road use types. Indicating the role of non-native propagule spread through the roads into the interior forest landscapes. The study gives a management implication, to restrict the non-native species spread from the road sides to the forest interior, irrespective of road use types. © Springer Science+Business Media B.V. 2008.PublicationArticle Status and direction of corporate social responsibility in Indian perspective: An exploratory study(2009) Sudhir Chandra DasPurpose The specific objectives of the study are to examine the contribution of center and state governments in social sector development and to demonstrate the strong sense of corporate social responsibility (CSR) models in an Indian perspective. Design/methodology/approach The study is exploratory in character and falls under the category of “general review” aimed at gaining familiarity and achieving insights into the phenomena i.e. status and direction of CSR in India. Findings The paper concludes that the social sector remained a neglected area as, despite a rise in their revenue earnings, the states are perennially in financial distress due to a more than proportionate increase in expenditure. The paper also highlights the poor budgetary allocation for education, ineffective doctorpatient ratio, heavy interest payments/servicing debt and lesser governmental efforts to initiate the CSR as a most effective tool. Further, the paper suggests three prospective CSR models in an Indian perspective. Research limitations/implications The present study provides a starting point for further research in the development of strategies to implement CSR models in India. Originality/value The paper concludes with a new dimension to CSR that refers to businesspeople focusing on business to community development, socially responsible products and processes and socially responsible employee relations. For researchers interested in the areas of models of CSR, the paper introduces a rich field for future research. © 2009, Emerald Group Publishing LimitedPublicationArticle Cost-effectiveness projections of single and combination therapies for visceral leishmaniasis in Bihar, India(2009) Piero Olliaro; Sarah Darley; Ramanan Laxminarayan; Shyam SundarObjectives: To assess the cost-effectiveness of current monotherapies and prospective combinations for treating visceral leishmaniasis (VL) in Bihar, India in terms of years of life lost (YLL) averted as well as deaths averted. Methods: We employed two methods to estimate the number of avertable deaths in our analysis: one using estimated mortality, the other using direct incidence estimates for VL. Costs of care are based on an average private hospital in Bihar, and data on drug costs were obtained both locally and from the World Health Organization. Results: The cost of monotherapies per averted YLL ranged from US$2 for paromomycin in an outpatient setting to US$20-22 for AmBisome® at 20 mg/kg. The corresponding costs per death averted ranged from US$53-54 to US$523-527. Combinations ranged US$5-8 per YLL averted and US$124-213 per death averted. Conclusion: The available treatments for VL are cost-effective, and our mortality and incidence-based methods produce consistent estimates. The combinations considered here were more cost-effective than most monotherapies. Having multiple treatment options and combining drugs are also likely to reduce drug pressure and prolong the drugs' life-span of effective use. © 2009 Blackwell Publishing Ltd.PublicationArticle Coding region of IRF6 gene may not be causal for Van der Woude syndrome in cases from India(2009) Akhtar Ali; Subodh Kumar Singh; Rajiva RamanObjective: Evaluation of the IRF6 gene in Van der Woude syndrome cases from an Indian population. Subjects: Nine affected and four unaffected individuals from seven families with Van der Woude syndrome as well as five normal controls (with no history of Van der Woude or any other congenital malformation and belonging to the same geographical area as the families with Van der Woude syndrome). Method: Direct sequencing of all coding regions and exon-intron boundaries of the IRF6 gene. Results: Five novel variants: IVS1+3900 A>G, 191 T>C, IVS4+775 C>T, IVS8+218 C>T, 1511 T>A (Ser 416 Arg) and two known variants: IVS6+27 C>G, 1083 G>A (V274I) were detected.Except for one, all were in noncoding regions either in 3′UTR or in introns. There was only one mutation in the coding region, detected in a normal control. Conclusion: The present report indicates that point mutations in the coding region of the IRF6 gene may not be a major cause of Van der Woude syndrome in Indian populations.PublicationArticle Saraswati: Crosslingual Sanskrit Digital Library(2009) Aditya TripathiPurpose The purpose of this paper is to describe Saraswati, a crosslingual Sanskrit Digital Library hosted at Banaras Hindu University. The system aims to assist those who know Sanskrit and at least one Indic script out of Devanagari, Kannada, Telugu and Bengali. Design/methodology/approach The system is developed with the Unicode standard using PHP as the programming language. The system follows three levels of architecture for search, display, and storage of Sanskrit documents. The system uses the UTF8 character representation system and generates onthefly transliteration from one Indic language script to another. Findings The system successfully demonstrates transliteration of Sanskrit text from one language to another. Saraswati is also capable of searching a given keyword across different languages and produces the result in the desired language script. Research limitations/implications Some languages such as Tamil (not chosen for study) use context dependent consonants, and with the present algorithm they require further refinement. Practical implications With Saraswati, people can read Sanskrit documents and also perform a search for documents available in other scripts. The present system is useful for reading crosslingual literature. The present study demonstrates successful implementation of Saraswati over the University Intranet. Social implications It is very common among scholars both in India and abroad that they learn Sanskrit with only one Indic script. The present system is helpful for such kind of scholars. Originality/value The system is the first of its kind anywhere and will be highly beneficial for scholars. © 2009, Emerald Group Publishing LimitedPublicationArticle A new find of boninite dyke from the Palaeoproterozoic Dongargarh Super group: Inference for a fossil subduction zone in the Archaean of the Bastar craton, Central India(2009) N.V. Chalapathi Rao; Rajesh K. SrivastavaThe Dongargarh Supergroup (DSG), a bimodal Large igneous province (LIP), is one of the Palaeoproterozoic greenschist facies-metamorphosed volcano-sedimentary belts in the Bastar craton of the Central Indian shield. Two contrasting models are in vogue for the generation of the mafic volcanics from the DSG - a continental rifting model and an arc related model. In this paper, we report the occurrence of a boninite dyke from the Bijli rhyolite Formation, which is the lower volcanic horizon in the Nandgaon Group of the DSG. The boninite dyke is characterised by high magnesium (MgO : 18.32-18.80 wt.%), primitive Mgnumber (Mg# >80), abundance of silica (SiO2: 51.63-51.95 wt.%), high Ni (-369 ppm), Cr (-2703 ppm). extremely low titania (TiO2: 0.04 wt.%), enrichment of LREE over MREE and HFSE and pronounced negative anomalies in Nb, Ti and Zr on primitive mantle normalized multi-element plots. The Dongargarh boninite dyke is inferred to have been derived from a primary magma and shares geochemical characteristics of modern- as well as Archaean-boninites. It comes under the high-Ca boninite category and displays distinct geochemical traits compared to the so far reported boninites from the Bastar craton. Its petrogenesis necessitates a two stage-model involving a refractory mantle as well as fluids derived from subducted sediments. Crustal assimilation (contamination) or a direct plume-derived melt cannot account for its observed geochemical characters. Even though we cannot constrain the generation of the mafic volcanics of DSG vis-à-vis rifting vs convergence with the available data, the occurrence and geochemistry of the boninite dyke indeed demonstrates that this domain represents a fossil subduction zone. © by E. Schweizerbart'sche Verlagsbuchhandlung 2009.