Scholarly Publications

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This community showcases the academic contributions of faculty and researchers at Banaras Hindu University (BHU) and provides a year-wise compilation of publications across disciplines. Institutional Repository BHU

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1 (2)gl gene regulates late expression of segment polarity genes in Drosophila
(1995) Ashim Mukherjee; S.C. Lakhotia; J.K. Roy
To analyse the possible roles of Drosophila tumour suppressor genes, 1 (2)gl and 1 (2)gd, in differentiation programmes of imaginal cells, we investigated their interactions with two segment polarity genes, viz., cubitus interruptus Dominant (ci-D) and engrailed (en), by examining their patterns of expression in tumourous imaginal discs of 1 (2)gl4 or 1 (2)gd1 homozygous larvae. While the 1 (2)gd1 mutation did not have much effect, the areas of expression of ci-D and en in the tumourous discs of 1 (2)gl homozygous larvae were significantly increased and the anterior-posterior compartment boundary was no longer identifiable. To examine if the loss of en expression compartment boundary in 1 (2)gl tumourous discs was due to overproliferation of the posterior compartment cells or due to a deregulated expression of en in the anterior compartment cells, 1 (2)gl4 homozygous cell clones were generated in 1 (2)gl4 enlacZ/++ background. A distinct X-gal staining in 1 (2)gl homozygous clones in the anterior compartment in wing imaginal discs or in adult wings confirmed deregulated ectopic expression of en in 1 (2)gl mutant anterior compartment cells. We suggest that 1 (2)gl is involved in regulating post embryonic expression of segment polarity genes. © 1995.
1, 1-Dithiolato-bridged heterobimetallic complexes containing a transition metal ion and oxouranium(VI)
(Kluwer Academic Publishers, 1990) Nanhai Singh; Nand K. Singh; Prahlad P. Agrawal
Anionic complexes [UO2(1, 1-dithiolate)2]2- interact strongly with transition metal ions to yield a new class of dithiolato-bridged heterobimetallic complexes MUO2(1, 1-dithiolate)2 (M=CoII, NiII, CuII, ZnII or PbII, 1, 1-dithiolate = isomaleonitrile dithiolate (i-MNT2-) and trithiocarbonate (CS32-)). (Et4N)2[UO2(i-MNT)2] and (Et4N)2[UO2(CS3)2] have also been prepared. The complexes have been characterized by elemental analysis, i.r., u.v.-vis. and e.s.r. spectral studies. The heterobimetallic complexes are non-electrolytic, whereas (Et4N)2-[UO2 (i-MNT)2] and (Et4N)2[UO2(CS3)2] are 2:1 electrolytes. The i.r. data indicate symmetrical bidentate bridging behaviour for the dithiolate ligands. Magnetic moments, electronic spectra and e.s.r. studies are commensurate with a square planar environment around CoII, NiII and CuII. © 1990 Chapman and Hall Ltd.
1, 3-Propanediamine, 1, 4-butanediamine (putrescine) and 1, 5-pentanediamine (cadaverine) complexes with zinc(ii), cadmium(ii) and mercury(ii) halides and pseudohalides
(1975) I.S. Ahuja; Raghuvir Singh
Coordination compounds formed by zinc(II), cadmium(II) and mercury(II) halides and pseudohalides with 1, 3-propane diamine, 1, 4-butanediamine (putrescine) and 1, 5-pentanediamine (cadaverine) have been prepared and characterized by molecular conductance and infrared spectral measurements down to 200 cm-1. Possible structures for these complexes in the solid state are discussed. © 1975, Taylor & Francis Group, LLC. All rights reserved.
1,10-Phenanthroline complexes of some uranyl salts
(1973) I.S. Ahuja; Rajindar Singh
[No abstract available]
1,2,3-Triazole-tethered fluoroquinolone analogues with antibacterial potential: synthesis and in vitro cytotoxicity investigations
(Royal Society of Chemistry, 2025) Upendra Kumar Patel; Alka; Punit Tiwari; Ragini Tilak; Gaurav Joshi; Roshan Kumar; Alka K. Agarwal
The antibacterial efficacy of some newly developed bis- and C3-carboxylic moieties of fluoroquinolone-linked triazole conjugates was studied. Twenty compounds from two different series of triazoles were synthesized using click chemistry and evaluated for their antibacterial activity against a Gram-positive strain, i.e. Enterococcus faecalis (ATCC29212), and its clinical isolate and a Gram-negative bacterial strain, i.e. Escherichia coli (ATCC25922), and its clinical isolate. Among the compounds, 7, 9a, 9d, 9i, 10(a–d), and 10i showed excellent activity with MIC values of up to 6.25 mg mL−1, whereas the control ciprofloxacin showed MIC values of up to 12.5 mg mL−1 towards the various strains. Cytotoxicity was evaluated against Vero cells (kidney epithelial cells of an African green monkey), and results revealed that compounds 9a, 9c, 10g, 10h, and 10 are toxic. Molecular docking and MD analysis were performed using the protein structure of E. coli DNA gyrase B and further corroborated with an in vitro assay to evaluate the inhibition of DNA gyrase. The analysis revealed that compound 10d was a more potent inhibitor of DNA gyrase compared to ciprofloxacin, which was employed as the positive control. © 2025 The Author(s).
1,2,3-Trioxygenated glucosyloxyxanthones from Polygala triphylla
(1981) Shibnath Ghosal; Prasad C. Basumatari; Shanta Banerjee
Four B-ring oxygen-free trioxygenated xanthones, viz. 1-OH-2,3-(OMe)2-, 1,2,3-(OMe)3-, 1-OH-2,3- (OCH2O)-, 1-OMe-2,3-(OCH2O)-xanthone, two B-ring oxygen-free glucosyloxyxanthones, viz. 1-O-gl.-2-OH-3-OMe- and 1-O-gl.-2,3-(OCH20)-xanthone, and a pentaoxygenated xanthone, 1-OMe-2,3,6,7-(OCH2O)2-xanthone, have been isolated from the flowering top of Polygala triphylla. The xanthones have been characterized on the basis of chemical transformation, comprehensive spectral evidence, and by direct comparison where possible. This is the first report of occurrence of the glucosyloxyxanthones in nature. The biochemical significance of these chemical characters in higher plants is appraised. © 1981.
1,3(n-π*) excited states of benzaldehyde
(Springer India, 1985) R.D. Tewari; P.C. Mishra
Geometries of the first triplet and first singlet n-π* excited states of benzaldehyde have been optimized using the sindo 1 molecular orbital wave-function (with CI) and the Newton-Raphson method. The triplet excited state geometry of the molecule is found to be appreciably non-planar whereas that of the singlet excited state is planar. A crossing of molecular orbitals occurs in going from the ground state equilibrium geometry to the triplet and singlet n-π* excited state equilibrium geometries. Existence of the para-directing effect of the singlet n-π* transition for electronic charges found in an earlier work is confirmed by the present work. The triplet n-π* excitation rearranges electronic charges mainly on the CHO group. It is found that the dipole moment of the molecule would appreciably increase following the singlet n-π* excitation whereas the same would appreciably decrease following the triplet n-π* excitation. © 1985 Indian Academy of Sciences.
1,3,4-Thiadiazoles as potential EP additives - a tribological evaluation using a four-ball test
(1995) A. Bhattacharya; T. Singh; V.K. Verma; N. Prasad
This paper reports a comparative study of the wear-reducing efficiency and extreme pressure properties of 0.5% ( w v) admixtures of paraffin oil and 2-amino-5-arylamino-1,3,4-thiadiazole additives and a commercial sulphur-phosphorus additive in a four-ball test. 2-Amino-5-p-Cl-phenylamino-1,3,4-thiadiazole additive shows excellent EP properties as is evident from the surface smoothness of SEM micrographs. The tribochemistry of the wear-scar surface has been investigated by the auger electron spectroscopy (AES) technique. © 1995.
1,3-bis(4-pyndyl)propane complexes of divalent metal halides and pseudohalides
(Kluwer Academic Publishers, 1978) Ishar Singh Ahuja; Raghuvir Singh; Chandra Pati Rai
Coordination compounds formed by the interaction of 1,3-bis(4-pyridyl)propane (DPP) with some divalent metal halides and pseudohalides have been prepared and characterized by magnetic susceptibilities, electronic and i.r. spectral measurements down to 200 cm-1 in the solid state. The i.r. spectra indicate that DPP acts mostly as a bidentate bridging ligand in these complexes. Moreover, the two pyridyl rings which are nonplanar in uncoordinated DPP become coplanar upon coordination. Tentative stereo chemistries of the complexes have been suggested in the solid state. The ligand field parameters Dq, B, β, λ and ν2/ν1 have been calculated for the cobalt(II) and nickel(II) complexes and are consistent with the proposed stereo chemistries. © 1979 Verlag Chemie, GmbH.
1,3-di-(4-pyridyl)propane complexes with some uranyl salts
(1976) I.S. Ahuja; Raghuvir Singh
[No abstract available]
1,3-Dipolar cycloaddition of diphenyl nitrile imine with 4-arylmethylene-2,4-dihydro-5-methyl-2-phenyl/phenylmethyl-3H-pyrazol- 3-ones
(1991) D. Singh
[No abstract available]
1-(2-Furoyl)-3-(2-methoxy-4-nitrophenyl)thiourea
(2013) Seema Pratap; Durga P. Singh; Sushil K. Gupta; Sema Öztürk Yildirim; Ray J. Butcher
The asymmetric unit of the title compound, C13H11N3O5S, contains two independent molecules, which are linked by a pair of intermolecular N - H⋯S hydrogen bonds, forming an R 2 2(8) ring motif. The central thiourea core forms dihedral angles of 3.02 (12) and 14.00 (10)° with the essentially planar furoyl groups [maximum deviations = 0.030 (2) and 0.057 (2) Å] in the two molecules and dihedral angles of 2.43 (13) and 8.03 (12)° with the benzene rings. The dihedral angles between the furoyl and benzene rings in the two molecules are 3.97 (10) and 5.98 (9)°. The trans-cis geometry of the thiourea group is stabilized by three intramolecular N - H⋯O hydrogen bonds involving carbonyl and methoxy O atoms with the H atom of the cis-thioamide group and between furan O atom and the other thioamide H atom. There is also a weak intramolecular C - H⋯S interaction in each molecule. © 2013 Pratap et al.
1-(Hydroxymethyl)-1H-benzotriazole: An Efficient Ligand for Copper-Catalyzed Ullmann-Type Coupling Reaction Leading to Expeditious Synthesis of Diverse Benzoxazoles and Benzothiazoles
(Wiley-Blackwell, 2019) Mala Singh; Priyanka Bose; Anoop S. Singh; Vinod K. Tiwari
Cu-catalyzed Ullmann coupling was performed for the facile synthesis of diverse benzoxazoles and benzothiazoles in the presence of 1-(hydroxymethyl)-1H-benzotriazole as ligand and K2CO3 as base in anhydrous DMF at 120 0C. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1-(Naphthalen-1-yl)-3-[(thiophen-2-yl)-carbonyl]thiourea
(2012) Durga P. Singh; Seema Pratap; Sushil K. Gupta; Ray J. Butcher
In the title compound, C16H12N2OS 2, the dihedral angles between the mean planes of the central thiourea core and the thiophene ring and the naphthalene ring system are 1.8 (2) and 6.45 (18)°, respectively. The molecule adopts a trans-cis conformation with respect to the position of thiophenoyl and naphthyl groups relative to the S atom across the thiourea C - N bonds. Both the thiophene ring and the sulfanylidene S atom are disordered over two sets of sites with occupancies of 0.862 (3):0.138 (3) and 0.977 (3):0.023 (3), respectively. An intramolecular N - H···O hydrogen bond is observed. The crystal packing features two N - H···S hydrogen bonds.
1‐Aryl‐2‐amino/hydrazino‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thione and Related Thiocarbamides/Thiosemicarbazides as Antithyroidal Agents
(1993) R. Prasad; P.K. Srivastava
Different 1‐aryl‐2‐benzylmercapto‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thiones have been synthesized by known methods. These triazines on treatment with ammonia/hydrazine hydrate afforded the corresponding 1‐aryl‐2‐amino/hydrazino‐4‐phenyl‐1,6‐dihydro‐1,3,5‐triazine‐6‐thiones which on treatment with arylisothiocyanates afforded the related thiocarbamides/thiosemicarbazides. Some of these compounds show appreciable antithyroidal activity. Copyright © 1993 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
1-Prop-2-ynyl-1H-benzimidazol-2-amine
(2011) Alka Agarwal; Manavendra K. Singh; Satish K. Awasthi
In the title compound, C10H9N3, the benzimidazol-2-amine and CH2 -C≡CH units are not coplanar, with a dihedral angle of 60.36°between their mean planes. The crystal structure is stabilized by intermolecular N-H⋯N hydrogen bonding and π-π interactions [centroid-centroid distances 3.677 (1) and 3.580 (1) Å], assembling the molecules into a supra-molecular structure with a three-dimensional network.
1.66-Ga-old metamorphosed Pb-Cu deposit in Sargipali (eastern India) : Manifestations of tidal flat environment and sedex-type genesis
(Elsevier B.V., 1996) Rajesh K. Vishwakarma
The metasedimentary rocks and the unusual Pb-Cu mineralization of the Sargipali mine area are described and discussed to elucidate the processes involved in their deposition. Important lines of evidences used for the interpretation of an inter- to supratidal flat environment are: (1) a general pattern of a shallowing upward sequence from coarse clastics (arenaceous) through finer clastics (argillaceous) to carbonate; (2) the occurrence of metaconglomerate, trough cross-bedding and wave-ripples (within the arenaceous lithostratigraphic unit); (3) intercalations of quartzite, carbonate skarn, dolomite, and convolution of chert laminae (within the argillaceous lithostratigraphic unit); and (4) intercalation of quartz-mica-chlorite schist laminae (within the carbonate lithostratigraphic unit). The ores seems to belong to the same environment. Furthermore, in the assessment of the origin of the Sargipali ores, it is recognized that the orebodies not only represent a sedimentary setting, but also show a high Pb-content, and an older age of mineralization than that of deformation, metamorphism and granite intrusion. Along with the lack of stockwork zones, wall rock alteration, subaerial volcanism, and the presence of chert and tourmalinite, these features are consistent with a sedex-type origin. The idea of this origin finds support by yet another observation, i.e., the ore sulphur was mainly derived from the inorganic reduction of the seawater sulphate (at more than 300°C), while the ore metals were leached from the μ (= 238U/204Pb) - enriched Singhbhum soda-granite of 2200 Ma. The present study may help in conceiving a 'new' possibility that the sediment-hosted Pb-rich deposits of MVT origin can also be evaluated in terms of the sedex model.
1/ƒ noise in the Ising model
(American Physical Society, 2025) Rahul Chhimpa; Avinash Chand Yadav
We simulate the N-spin critical Ising model on a square lattice using Glauber dynamics and consider the typical one-unit time equal to N single-spin-flip attempts. The divergence of correlation time with the linear extent of the system results in critical slowing down, a challenge to equilibration because the spin configurations generated in such a way are temporally correlated. We examine temporal correlations in the number of accepted spin flips and show a signature of nontrivial long-time correlation of a logarithmically decaying form, or the corresponding power spectral density follows canonical 1/ƒ noise. ©2025 American Physical Society.
1/fα noise in the Robin Hood model
(Institute of Physics, 2024) Abha Singh; Rahul Chhimpa; Avinash Chand Yadav
We consider the Robin Hood dynamics, a one-dimensional extremal self-organized critical model that describes the low-temperature creep phenomenon. One of the key quantities is the time evolution of the state variable (force noise). To understand the temporal correlations, we compute the power spectra of the local force fluctuations and apply finite-size scaling to get scaling functions and critical exponents. We find a signature of the 1 / f α noise for the local force with a nontrivial value of the spectral exponent 0 < α < 2 . We also examine temporal fluctuations in the position of the extremal site and a local activity signal. We present results for different local interaction rules of the model. © 2024 IOP Publishing Ltd and SISSA Medialab srl. All rights, including for text and data mining, AI training, and similar technologies, are reserved.
100 kyr sedimentary record of Marginal Gangetic Plain: Implications for forebulge tectonics
(Elsevier B.V., 2019) Rupa Ghosh; Pradeep Srivastava; U.K. Shukla; R.K. Sehgal; I.B. Singh
The Gangetic Foreland is a consequence of continent-continent collision and formation of the Himalayan thrust and fold belt. In the more distal part of the peripheral Gangetic foreland basin, the Late Quaternary sedimentary architecture analysis from 17 stratigraphic successions together with optically stimulated luminescence dating (OSL) divulge interaction of peripheral bulge tectonics and climate over the past ~100 kyr. These sections exhibit three sedimentary packages formed under different environmental conditions. Detailed vertical and lateral sedimentary architecture delineates nine lithofacies that are grouped into three facies associations, (i) flood plain facies association, (ii) channel facies association, and (iii) interfluve facies association. The basal package-I, >114 ka old, was deposited by sandy meandering channels and overlying to this with a hiatus of ~30 ka is package-II, ~80–54 ka, deposited by gravelly rivers. The sediments of both the packages-I, II are derived from rocks exposed in the peripheral bulge region. Overlain package- III, deposited by small meandering channels, consist of the sediments derived from the Himalaya. The results indicate that the duration of 80–54 ka was a period of forebulge uplift when gravelly fans prograded basinward. Below the fan sediments lies a peripheral bulge unconformity marked by regionally significant pedogenic horizon. This pedogenic horizon qualifies as to be termed as peripheral bulge uncomformity. After 54 ka, the fine Himalayan sediments onlap the cratonic sediments implying rather a stable forebulge tectonics coupled with fluctuating climatic conditions, occasionally bringing micaceous gray coloured sand-silt of Himalayan origin. © 2019 Elsevier B.V.