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1891-1883 Ma Southern Bastar-Cuddapah mafic igneous events, India: A newly recognized large igneous province
(2008) Jason E. French; Larry M. Heaman; Thomas Chacko; Rajesh K. Srivastava
A newly recognized remnant of a Paleoproterozoic Large Igneous Province has been identified in the southern Bastar craton and nearby Cuddapah basin from the adjacent Dharwar craton, India. High precision U-Pb dates of 1891.1 ± 0.9 Ma (baddeleyite) and 1883.0 ± 1.4 Ma (baddeleyite and zircon) for two SE-trending mafic dykes from the BD2 dyke swarm, southern Bastar craton, and 1885.4 ± 3.1 Ma (baddeleyite) for a mafic sill from the Cuddapah basin, indicate the existence of 1891-1883 Ma mafic magmatism that spans an area of at least ∼90,000 km2 in the south Indian shield. This record of ∼1.9 Ga mafic/ultramafic magmatism associated with concomitant intracontinental rifting and basin development preserved along much of the south-eastern margin of the south Indian shield is a widespread geologic phenomenon on Earth. Similar periods of intraplate mafic/ultramafic magmatism occur along the margin of the Superior craton in North America (1.88 Ga Molson large igneous province) and in southern Africa along the northern margin of the Kaapvaal craton (1.88-1.87 Ga dolerite sills intruding the Waterberg Group). Existing paleomagnetic data for the Molson and Waterberg 1.88 Ga large igneous provinces indicate that the Superior and Kalahari cratons were at similar paleolatitudes at 1.88 Ga but a paleocontinental reconstruction at this time involving these cratons is impeded by the lack of a robust geological pin such as a Limpopo-like 2.0 Ga deformation zone in the Superior Province. The widespread occurrence of 1.88 Ga intraplate and plate margin mafic magmatism and basin development in numerous Archean cratons worldwide likely reflects a period of global-scale mantle upwelling or enhanced mantle plume activity at this time. Crown Copyright © 2007.
2-deoxy-D-Glucose alters the cardio-respiratory parameters in anaesthetized rats
(2008) R. Pandey; P.K. Choudhry; S.B. Deshpande
2-Deoxy-D-Glucose (2-DG), a synthetic analogue of glucose, is used as an anticancer agent either alone or in combination with other tumor treatment protocols. The present study was conducted to identify the systemic effects of 2-DG on parameters of vital importance. The blood pressure, ECG and respiratory excursions were recorded in anesthetized adult rats. At the end (after 120 min) of experiments, the plasma glucose and serum insulin levels were estimated. Injection of 2-DG (0.5 g/kg) produced an immediate increase in mean arterial pressure (MAP) and respiratory rate. The increase in MAP continued throughout the period of observation (120 min) and the maximal increase was seen at 90 min (27%). Whereas, the respiratory rate decreased by 17% at 15 min which decreased further to 37% by 120 min. Heart rate also decreased after 2-DG in a time-dependent manner and 40% decrease was observed at 120 min. Administration of 2-DG increased the plasma glucose level significantly (30%) as compared to saline control group but did not increase the serum insulin level. The results indicate that 2-DG alters the cardio-respiratory parameters by mechanisms unrelated to plasma insulin activity.
3-Nitropropionic acid-induced depression of spinal reflexes does not involve 5-hydroxytryptaminergic system in contrast to ischemia-induced depression in neonatal rat spinal cord in vitro
(2008) Rajesh Gupta; Archana Jha; Shripad B. Deshpande
The involvement of 5-hydroxytryptaminergic (5-HTergic) system for the 3-nitropropionic acid (3-NPA)-induced depression of spinal reflexes was evaluated and compared with other energy deficiency condition (ischemia; glucose-free and O2-free). The monosynaptic (MSR) and polysynaptic reflex (PSR) potentials were recorded at ventral root by stimulating the corresponding dorsal root in neonatal rat spinal cord in vitro. Superfusion of 3-NPA (3.4 mM) or ischemic solution depressed the reflexes in a time-dependent manner abolishing them by 35 min. Pretreatment with pindolol (1 μM), ketanserin (10 μM) or ondansetron (0.1 μM); 5-HT1, 5-HT2, or 5-HT3 receptor antagonist, respectively, did not block the 3-NPA-induced depression of reflexes whereas, ischemia-induced depression was blocked by ondansetron. 5-HT content of the spinal cords incubated with 3-NPA (3.4 mM) for 30 min was decreased significantly (33 ng/g tissue) while increased (286 ng/g) in cords exposed to ischemic solution as compared to saline-treated cords (161 ng/g). Thus, 3-NPA-induced depression of spinal reflexes does not involve 5-HTergic pathway unlike ischemia-induced depression. © 2008 Elsevier Ireland Ltd. All rights reserved.
3-Nitropropionic acid-induced depression of spinal reflexes involves mechanisms different from ischemia-induced depression
(2008) Rajesh Gupta; Shripad B. Deshpande
Effect of 3-nitropropionic acid (3-NPA) and ischemia (glucose- and O2-free solution) on synaptic transmission in hemisected spinal cord from 4 to 8 day old rats was examined in vitro. Stimulation of a dorsal root (L3-5 segments) evoked monosynaptic (MSR) and polysynaptic reflex (PSR) potentials in the segmental ventral root. Superfusion of 3-NPA (0.17-3.4 mM) depressed the reflexes in a concentration- and time-dependent manner. At 3.4 mM of 3-NPA, the reflexes were abolished by 35 min. Time required to produce 50% depression (T-50) was around 170, 80, 40 and 17 min for MSR and 110, 70, 25 and 16 min for PSR at 0.17, 0.51, 1.7 and 3.4 mM of 3-NPA, respectively. Ischemia also produced a time-dependent depression of reflexes and abolished them by 35 min and the T-50 values were around 18 min. Presence of creatine phosphate (10 mM) in the superfusing medium did not alter the time course of 3-NPA-induced depression of reflexes but prolonged the ischemia-induced depression. dl-2-amino-5-phosphonovaleric acid (NMDA receptor antagonist; 10 μM) failed to block the 3-NPA (3.4 mM)-induced depression of reflexes, but blocked the ischemia-induced depression. The results indicate that 3-NPA-induced depression of spinal reflexes does not involve NMDA receptors and is different from ischemia-induced depression. © 2008 Elsevier Inc. All rights reserved.
A bibliometric study of Embelia ribes
(2008) Gian Singh; Moin Ahmad; Mohammad Nazim
Purpose - The study aims to present a bibliometric analysis of scientific output of the plant Embelia ribes, the aim being to offer an overview of research activity in this field and characterize its most important aspects. Design/methodology/approach - A total of 332 articles were collected from following databases: Pub Med, Medicinal and Aromatic Plants Abstract, Indian Science Abstract and Biological Abstract. The searches were restricted to published articles and contain the terms Embelia ribes and Vidanga. The various analyses focus on growth of literature, authorship pattern, most prolific authors, core journals of the subject, most productive institutes and countries. Lotka's law and bradford' law of scattering were applied to count the author productivity and core journals in the subject. Findings - Most articles involved collaboration between two or three authors Author productivity was not found exactly fit to Lotka's law with a value of n = 2. However, distribution of articles in different journals was found fit to Bradford's law of scattering with the distribution of 1:n: n2. Originality/value - The paper offers an overview of research activity into the plant Embelia ribes.
A clinicoepidemiological study of polymorphic light eruption
(Medknow Publications and Media Pvt. Ltd, 2008) Lata Sharma; A. Basnet
Background and Aims: The prevalence of polymorphic light eruption (PLE) varies between 10-20% in different countries but no such data is available from India, where exposure to sunlight is high. Methods: A clinico-epidemiological study of PLE was done in the skin outpatient department (OPD) of Institute of Medical Sciences Hospital from January to December. Results: The ages of the patients varied from 5-70 years. Out of a total of 39,112 OPD cases, 220 cases of PLE (138 females and 82 males) were recorded, giving a prevalence of 0.56% in this study population. The skin type varied between IV and VI in 96% of the cases. Housewives were 81, students 67, office persons 39, farmers 22, businessmen 6 and unemployed 5. Discussion: The manifestation of PLE was most common in housewives in areas exposed to the sun. Most of the PLE patients presented with mild symptoms and rash around the neck, forearms and arms which was aggravated on exposure to sunlight. PLE was more prevalent in the months of March and September and the disease was recurrent in 31.36% of the cases. Conclusions: The prevalence of PLE was 0.56%. It was mild in nature and only areas exposed to the sun were involved.
A comparative study of antioxidative defense system in the copper and temperature acclimated strains of Anabaena doliolum
(2008) Yogesh Mishra; Poonam Bhargava; Riti Thapar; Ashish Kumar Srivastava; Lal Chand Rai
This study provides first hand comparative account of growth and antioxidative defense system of the wild type, Cu2+ and temperature treated wild type and acclimated strains of Anabaena doliolum Bharadwaja against Cu2+ and high temperature. The acclimated strains showed perceptible growth at 250 μM Cu2+ and 47°C temperatures, respectively. In contrast to this the wild type strain on exposure to 50 μM Cu2+ and 47°C temperature depicted almost complete inhibition of growth. However, the peroxide content was significantly higher in the acclimated strains than the wild type. Superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) showed maximum activity at high temperature followed by Cu2+ acclimated and minimum in the wild type strains. The ascorbate (ASC) and glutathione (GSH) contents were increased by 2.3 and 43.3, and 15.5 and 36.5-fold in Cu2+ and 47°C acclimated strains, respectively. However, when the wild type strain was subjected to Cu2+ and temperature all antioxidative enzymes except SOD showed inhibition of their activity. In case of wild type the GSH content was inhibited by 0.39-fold at 50 μM Cu2+ but the ASC content registered increase by 2 and 2.7-fold on subjecting to Cu2+ and temperature, respectively. Thus increased activity of enzymatic antioxidants as well as accumulation of ascorbate and glutathione in both the acclimated strains suggests that enzymatic and non-enzymatic antioxidants help in the acclimation of A. doliolum Bharadwaja against Cu2+ and high temperature. However, inhibition of antioxidative defense system of wild type under Cu2+ and heat stress appears to be the reason for its non survival. In view of the appreciable increase in the level of antioxidants as well as greater inhibition of specific growth rate in temperature than Cu2+ acclimated strains, temperature (47°C) is proposed to be is more deleterious to the organism than copper (250 μM). © 2008 Springer Science+Business Media B.V.
A comparative study of polyanthranilic acid (pANA)/metal and polycarbazole (Pcz)/metal contacts for electronic and optoelectronic applications
(2008) A.D.D. Dwivedi; Arun Kumar Singh; Rajiv Prakash; P. Chakrabarti
We report fabrication and characterization of an organic photodetector (OPD) in the form of ITO coated glass / Polycarbazole (PCz) /Al Schottky contact for application in visible region and Al/PANA/ITO, Ti/PANA/ITO Schottky contacts of application in U. v: region. The current voltage (I-V) characteristics of the devices were measured by using microprobe arrangement. The performance parameters of ITO / Polycarbazole (PCz)/Al Schottky contact have been compared and contrasted with those of ITO/PANA/Al and ITO/PANA/Ti Schottky contacts. UV-Vis spectroscopic measurement revealed strong absorption spectra of the two types of devices in the visible and U.V. region respectively.
A computational method of forecasting based on fuzzy time series
(2008) S.R. Singh
In this paper, a computational method of forecasting based on fuzzy time series have been developed to provide improved forecasting results to cope up the situation containing higher uncertainty due to large fluctuations in consecutive year's values in the time series data and having no visualization of trend or periodicity. The proposed model is of order three and uses a time variant difference parameter on current state to forecast the next state. The developed model has been tested on the historical student enrollments, University of Alabama to have comparison with the existing methods and has been implemented for forecasting of a crop production system of lahi crop, containing higher uncertainty. The suitability of the developed model has been examined in comparison with the other models to show its superiority. © 2008 IMACS.
A convenient synthesis of some coumarin derivatives using SnCl2 • 2H2O as catalyst
(2008) K.K. Upadhyay; Rakesh K. Mishra; Ajit Kumar
Some substituted coumarins have been synthesized by von-Pechmann condensation using SnCl2 • 2H2O (10 mol %) as catalyst in ethanolic medium. The reactions are simple, easy in handling and environmentally benign. © 2007 Springer Science+Business Media, LLC.
A facile one-pot MW approach for 3-heteroaryl-2-thioxo-2,3- dihydroquinazolin-4(1H)-one
(Arkat, 2008) Vinod K. Tiwari; Raju R. Kale; Bhuwan B. Mishra; Archana Singh
A microwave-assisted simple, convenient, and high yielding synthetic methodology for diverse thioquinozolinones was developed by the amidine base catalyzed one-pot reaction of anthranilate ester, 1,1′- carbonothioylbis(1H-benzotriazole), and heterocyclic amines containing thiazole, [1,3,4]-oxadiazoles and [1,3,4]-thiadiazole heterocycles. ©ARKAT USA, Inc.
A field-theoretic model for Hodge theory
(2008) Saurabh Gupta; R.P. Malik
We demonstrate that the four-dimensional (4D) ((3+1)-dimensional) free Abelian 2-form gauge theory presents a tractable field-theoretical model for the Hodge theory where the well-defined symmetry transformations correspond to the de Rham cohomological operators of differential geometry. The conserved charges, corresponding to the above continuous symmetry transformations, obey an algebra that is reminiscent of the algebra obeyed by the cohomological operators. The discrete symmetry transformation of the theory represents the realization of the Hodge duality operation that exists in the relationship between the exterior and co-exterior derivatives of differential geometry. Thus, we provide the realizations of all the mathematical quantities, associated with the de Rham cohomological operators, in the language of the symmetries of the present 4D free Abelian 2-form gauge theory. © 2008 Springer-Verlag / Società Italiana di Fisica.
A jain perspective on nonviolence and warfare
(Bloomsbury Publishing Plc., 2008) Padmanabh S. Jaini
[No abstract available]
A new chalcone glycoside from Rhamnus nipalensis
(2008) M.B. Pandey; A.K. Singh; U. Singh; S. Singh; V.B. Pandey
A new chalcone glycoside, chalcone-2′,4-dihydroxy-4′-O-β-D-glucoside has been isolated from Rhamnus nipalensis together with sitosterol, lupeol, di-O-methyldaidzein, kaempferol-4′-methylether, quercetin, physcion, sitosterol glucoside, emodin and their structures established by spectroscopic data. Isolation of these compounds are the first report from this plant.
A new occurrence of sapphirine-bearing granulite from Podur, Andhra Pradesh, India
(Springer Wien, 2008) I.N. Sharma; D. Prakash
We report here on a new occurrence of sapphirine bearing granulites in the high-grade granite gneisses from Podur. Podur is situated in the north-eastern part of the Eastern Dharwar Craton about 150 km NNE of Hyderabad, India. The common stable assemblage contains cordierite-biotite-sapphirine-spinel-corundum-K-feldspar. Interpretation of multiphase reaction textures in conjunction with mineral chemical data and topology in the (Fe,Mg)O-(Al2O3 -K2O)-(SiO2-6K2O) system is consistent with the following reactions: biotite + corundum = spinel + K-feldspar + H2O phlogopite (in biotite) + corundum = eastonite (in biotite) + spinel + cordierite spinel + cordierite = sapphirine2:2:1* cordierite + biotite + corundum = sapphirine7:9:3* + K-feldspar + H2O sapphirine7:9:3 + biotite = cordierite + spinel + K-feldspar + H2O sapphirine = cordierite + spinel + corundum The P-T evolution of these sapphirine granulites has been constrained through the use of conventional geothermobarometry and THERMOCALC program. The P-T conditions of metamorphism from different pertinent calibrations are estimated to be around 6.5-7.0 kbar and 750-800 °C, respectively. On the basis of the available evidence for a 2.6 Ga granulite facies event in the Karimanagar granulite belt, the emerging concept of East Gondwana assembly is endorsed. © Springer-Verlag 2007.
A new reaction of dithiocarbamates: CS2 elimination and two C-C bond formations leading to formation of cyclic ammonium salts
(2008) Jyotsna Chaturvedi; Subrato Bhattacharya; M. Nethaji
Sodium salts of N,N-dibenzyldithiocarbamate, N,N-diisopropyldithiocarbamate and pyrrolidine-1-carbodithioate gave cyclic products, 4-oxo-2,6-diphenyl-piperidinium, 2,2,6,6-tetramethyl-4-oxo-piperidinium and 3-oxo-8-azonia-bicyclo[3.2.1]octane cations, respectively, when treated with aluminum trichloride in acetone. The 2,2,6,6-tetramethyl-4-oxo-piperidinium thiocyanate salt has been characterized by X-ray crystallography. A plausible mechanism has also been suggested on the basis of preliminary DFT calculations. © 2008 Elsevier B.V. All rights reserved.
A novel combination of the essential oils of Cinnamomum camphora and Alpinia galanga in checking aflatoxin B1 production by a toxigenic strain of Aspergillus flavus
(2008) Bhawana Srivastava; Priyanka Singh; Ravindra Shukla; Nawal Kishore Dubey
The growth of a toxigenic strain (Saktiman 3Nst) of Aspergillus flavus decreased progressively with increasing concentration of essential oils from leaves of Cinnamomum camphora and rhizome of Alpinia galanga incorporated into SMKY liquid medium. The oils significantly arrested aflatoxin B1 elaboration by A. flavus. The oil of C. camphora completely checked aflatoxin B1 elaboration at 750 ppm (mg/L) while that of A. galanga showed complete inhibition at 500 ppm only. The oil combination of C. camphora and A. galanga showed more efficacy than the individual oils showing complete inhibition of AFB1 production even at 250 ppm. © 2007 Springer Science+Business Media B.V.
A novel design of nano layered optical fllter using photonic band gap materials
(2008) S.K. Srivastava; S.P. Ojha
Much interest has been drawn in Photonic crystal, which are novel nanostructure of light. In the present paper, we present how the emerging technology of Photonic crystal can be suitably exploited to design and make a nano sized tunable optical filter. A novel theory to design tunable optical filter using one -dimensional nano photonic structure is proposed in this present paper for ultraviolet and visible region ofwavelength. A periodic structure ofdifferent dielectric and semiconductor materials (i.e. air and GaAs, air and Ge) are used. This idea is based on the Kronig -Penny model in the band theory of solids. A detail mathematical analysis is proposed to predict the allowed and forbidden bands of wavelength with variation of angle of incidence and lattice parameter. It is possible to desired range of electromagnetic spectrum filtered with structure by changing the incidence angle of light and/ or changing the lattice parameter. The proposed filter structure can act as narrow band wavelength selector and wide band selector in the same region. The properties of the filter structure depend on the thickness of the two alternate regions for the selected materials. The proposed nano layered tunable optical filter may be suitably exploited in recent integrated optics, WDM technology, space technology, Acousto-optic tunable filter, communication, medical etc.
A pilot study on the role of T-tube in typhoid ileal perforation in children
(2008) Anand Pandey; V. Kumar; Ajay N. Gangopadhyay; Vijai D. Upadhyaya; A. Srivastava; Ram B. Singh
Background: Ileostomy is usually performed for patients of typhoid intestinal perforation with poor general condition, but it is associated with significant morbidity. We have used the T-tube in such patients as an alternative to ileostomy. Methods: This is a prospective evaluation of a cohort of children with proven typhoid intestinal perforation. Patients with multiple perforations and poor general condition were managed with a T-tube inserted into the bowel lumen after closing all distal perforations (group 3). They were compared with patients who had primary closure of perforation (group 1) or bowel resection (group 2) to determine the efficacy of the use of T-tube. Results: The total number of patients for groups 1, 2, and 3 was 51, 4, and 12 (n = 67). The mean number of perforations for the three groups was 1, 3.5 ± 0.58, and 4.25 ± 0.97. The operation time for the three groups was 37.29 ± 3.24, 59.25 ± 3.09, and 59.17 ± 4.17 minutes, respectively. The T-tube was removed after 13.17 days. The mean duration of fistula at T-tube site to heal was 8.58 ± 2.11 days. The overall follow-up period was 10.94 ± 1.15 months and none of the patients with T-tube placement had features of intestinal obstruction. Conclusions: In children with multiple typhoid intestinal perforations and poor general condition, the use of T-tube may be an effective management option. © 2008 Société Internationale de Chirurgie.
A preliminary study on the significant value of beta-2-microglobulin over serum creatinine in renal transplant rejection and renal failure
(2008) G.K. Sonkar; Usha; R.G. Singh
Introduction: Beta-2-microglobulin (β2M) is a light chain of HLA class I molecule, which is filtered by glomerulus, reabsorbed and catabolised by proximal tubule. It is one of the markers of transplant rejection. The aim of the present study was to find out the level of β2M in acute renal failure (ARF), chronic renal failure (CRF), renal transplant rejection (TR) and renal transplantation stable (TS) cases, and correlation of β2M with serum creatinine (SCr) in assessing renal failure. Methods: 23 patients with ARF, 22 patients with CRF, six cases of TR, seven patients with TS, and 28 normal healthy controls were studied within a one-year period. Results: Highest mean value of β2M was noted (12.97 +/- 3.83 μg/ml) in CRF, and all cases had elevated β2M of which 81.8 percent of cases had β2M above 10 μg/ml. In ARF, all cases had elevated β2M and 78.3 percent patients had a value more than 10 μg/ml with a mean value of 11.75 +/- 2.09 μg/ml. TR cases also had elevated β2M but 50 percent had mild elevation (less than 10 μg/ml) and 50 percent had marked elevation (more than 10 μg/ml). 42.8 percent of TS patients also had mild elevation of β2M in the range 2.10-3.70 μg/ml. Interestingly, in normal healthy controls, 21.4 percent of patients had mild elevation of β2M of 2.1-2.75 μg/ml, while 78.6 percent of cases had a normal range of β2M (less than 2 μg/ml). All normal healthy controls and 71.4 percent of TS cases had normal SCr (less than 1.4 mg/dL). All cases of CRF and TR cases, and 28.6 percent of TS cases had elevated SCr. 81.8 percent of cases with CRF and 60.9 percent of cases with ARF had a marked rise of serum creatinine above 5 mg/dL. Conclusion: Our study showed that β2M is not superior over SCr for renal failure and TR cases, because it is also elevated in 21.4 percent of normal controls and 42.8 percent of TS cases. SCr is a cheaper, simpler and comparatively good test to assess renal failure and TR.

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