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PublicationArticle Bioremediation of Imidacloprid in a Stirred Tank Reactor Using Bacterial Consortium: Kinetic Analysis and Toxicity Assessment(American Chemical Society, 2023) Sonam Tiwari; Pranjal Tripathi; Devendra Mohan; R.S. SinghImidacloprid is an insecticide of systemic nature that exhibits an adverse impact on several non-target organisms. In the present study, potential bacteria have been isolated and used for biodegradation of imidacloprid in batch studies and stirred tank reactor. The optimum process condition for degradation has been found to be at pH 7, a temperature of 35 °C, and a shaking speed of 150 rpm. Maximum degradation of 78% has been achieved by the bacterial consortium in the batch study, while, in the reactor, it increases to 90%. Kinetics analysis suggests that the Teisser model best fits the experimental data, with a correlation coefficient (R2) of 0.98. Ecotoxicological assessment using luminescent bacteria reveals 40% and 90% inhibition in luminescence in the case of untreated sample upon exposure for 30 min and 24 h, respectively, while the values obtained in the case of treated samples are 9% and 29%, respectively. Cytotoxicity assessment indicates 60% reduction in cell proliferation in untreated samples and <10% cell proliferation inhibition in treated samples, indicating a considerable decrease in toxicity post-bacterial treatment. © 2023 American Chemical SocietyPublicationReview Effect of plant growth-promoting rhizobacteria on alleviating salinity stress in plants: a review(Taylor and Francis Ltd., 2023) Ashok Kumar; Itishree Behera; Mrinalini Langthasa; Sai PrakashNarojuSalt stress is a significant complication persisting in the soils of agricultural fields which contributing major stress factor for the inefficient growth and development of plants leading to declined productivity and soil degradation worldwide. Therefore, it would be beneficial to develop salinity stress tolerant plant species and to grasp the mechanism of stress tolerance that simulates the assembly of bioactive diffusion compatible matter that are of good significance to salt stress conditions. The plant growth-promoting rhizobacteria (PGPR) will be the reliable agents to control and manage the salinity stress in plants under direct and indirect mechanisms. Application of salinity tolerant PGPR inoculates could be a promising tool to combat salinity in agricultural fields, thereby increasing worldwide food production. The useful effects of PGPR involve boosting key physiological processes as well as water and nutrient uptake, photosynthesis and source sink relationships that promote growth and development. This article explores the mechanisms of PGPRs tolerant to salt stress in different plants and the genes responsible for the process. Considering all of the available existing mechanisms, genes of different microbes and plants which facilitate the resistance to plants for salt stress can be studied. © 2022 Taylor & Francis Group, LLC.PublicationArticle Combining ability analysis for grain filling duration and yield traits in spring wheat (Triticum aestivum L. em. Thell.)(Brazilian Journal of Genetics, 2007) Kamaluddin; Rishi M. Singh; Lal C. Prasad; Malik Z. Abdin; Arun K. JoshiA diallel analysis of wheat (Triticum aestivum L. em. Thell) parents (n = 11) and their F1 (n = 55) and F2 (n = 55) offspring was carried out for the following four traits: grain filling duration (GFD), GFD for growing degree days (GDD), 1000 seed weight and seed yield per plant. Analysis of variance for general combining ability (GCA) and specific combining ability (SCA) displayed significant F1 and F2 general and specific combining ability effects for the four traits studied. For all the traits the GCA effects were relatively more important than the SCA effects, indicating that additive genetic effects were predominant. Crosses displaying high SCA effects for grain filling duration, seed weight and yield were observed to be derived from parents having various types of GCA effects (high x high, high x low, low x low and medium x low). The single seed descent method can be applied to exploit additive gene effects whereas dominance gene effects could be valuable in hybrid wheat breeding programs. Among the parents, genotypes from the International Maize and Wheat Improvement Center (Centro Internacional de Mejoramiento de Maíz y Trigo, CIMMYT) as well as South Asia were found to be superior general combiners for grain filling duration. Likewise, crosses involving diverse parents from CIMMYT and South Asia showed significant SCA effects for grain filling duration and other traits. Copyright by the Brazilian Society of Genetics.PublicationArticle Numerical Analysis of a Collapsed Tunnel: A case study from NW Himalaya, India(Springer, 2022) A. Srivastav; V.H.R. Pandey; A. Kainthola; P.K. Singh; V. Dangwal; T.N. SinghThe present research explores the effect of various support system on deformation in a shallow tunnel from North-Western Himalaya, India. The deformation measurements assessed through field investigation were utilized to simulate the pre-existing and the present ground scenario, and furthermore in the evaluation of elastic parameters such as Young’s modulus and Poisson’s ratio through finite element back analysis. Back-analysed model predicted a Young’s modulus of 32 MPa and Poisson’s ratio of 0.3. Afterwards, the effect on the deformation of surrounding groundmass for unexcavated and the present condition were numerically ascribed at three different stages of excavation. The numerical application of forepoling and steel liners showed a marked reduction in the tunnel deformation. The combined effect of applied support methods was also enumerated and compared with individual stabilization method. This assessment may aid engineers and planners working in similar geological conditions, by making the excavation safer, stable and economical. © 2021, Indian Geotechnical Society.PublicationArticle Effects of electric field and temperature on spontaneous polarization in the vicinity of isotropic to antiferroelectric B2 phase transition in a banana-shaped mesogen 12OSOR(Taylor and Francis Inc., 2015) Shubha Singh; Shri SinghUsing a phenomenological free-energy density expansion, in this work, we have studied the effects of temperature and electric field on the spontaneous polarization of antiferroelectric B2 phase in the vicinity of I-B2 phase transition in a bent-core mesogen 12OSOR. The free-energy density of the system is written in terms of tensor orientational order parameter Qij, scalar smectic order parameters φ1 and φ2, the vector polarization order parameter Pa and the resulting couplings between these order parameters. Using the Landau coefficients, as determined from the experimental values of relevant quantities, we evaluate the temperature and electric field variations of spontaneous polarization and found that the theoretical results agree well with the experimental data of bent core achiral thioester mesogen 12OSOR. Copyright © Taylor & Francis Group, LLC.PublicationArticle Triplet-singlet emission spectra of p-benzoquinone-H4 and -D4 in the vapour state(1965) M.G. Jayswal; R.S. SinghThe visible emission spectra of p-benzoquinone-H4 and -D4 have been recorded, in the vapour state, in the presence of flowing vapour of toluene. The spectra lie in the region 6843 Å to 5226 Å. The band at 18683 cm-1 has been identified as the OO band for both the p-benzoquinones. The frequencies of p-benzoquinone-D4 show small violet shift relative to the frequencies of p-benzoquinones-H4. The spectra have been analysed with the help of three totally symmetric ground state vibrations: p-benzoquinone-H4/D4: 1675/1667 (CO stretching); 761/735 (ring breathing) and 437/423 (ring deformation, in the molecular plane) cm-1. The emission involves 3Au → 1Ag transition in both cases. © 1965.PublicationArticle Weed growth, nutrient removal and yield of direct-seeded rice as influenced by establishment methods and chemical-cum-mechanical weed management practices(Elsevier Ltd, 2023) Vijay Pratap; S.K. Verma; Anchal DassDirect seeding of rice (Oryza sativa L.) has since long been viewed as a potential alternative to unsustainable water-intensive transplanted rice (TPR) world-over, but heavy infestation of a variety of weed species limits the large-scale adoption of direct-seeded rice (DSR) cultivation. Hence, a 2-year field investigation was carried-out in a spilt-plot design, at Banaras Hindu University, Varanasi, during rainy seasons of 2016 and 2017 to assess the influence of various crop establishment methods (CEMs) and weed management options (WMs) on diverse weed-flora, nutrient removal by weeds, weed-control efficiency (WCE) and yield of DSR (cv. Rajendra Kasturi). The results revealed that zero-till DSR + residue + Sesbania brown manure (ZTDSR + R + SBM) was most effective in containing crop-weed competition, lowered density of Echinochloa colona (L.) Link, Echinochloa crusgalli (L.) Beauv., Cynodon dactylon (L.) Pers., Eclipta alba (L.) Hassak., Caesulia axillaris Roxb., Cyperus rotundus L., Cyperus iria L., Fimbristylis miliacea (L.) Vahl. by 63.4% and enhanced grain yield by 22.8%. Further, applying pendimethalin at 1000 g ai ha−1 as PRE. and later post-emergence (POST) spray of chlorimuron + metsulfuron at 4 g ai ha−1 each 20 days after sowing (DAS) supplemented with 1 hand-weeding (HW) 45 DAS was found to be a better weed management option as this treatment recorded the lowest density and nutrient depletion by above mentioned weeds and higher WCE, thereby improving rice yield by 3–19.5% over other studied WMs. Also, the combination of this weed management option with ZTDSR + R + SBM suppressed weeds to a greater extent, restricting weeds to deplete nutrients (N, P and K) from the soil and finally fetched the highest DSR yield. © 2022 Elsevier LtdPublicationArticle Developmental expression, co-localization and genetic interaction of exocyst component Sec15 with Rab11 during Drosophila development(Elsevier Inc., 2019) Tanmay Bhuin; Jagat K. RoySec15, a component of an evolutionarily conserved octomeric exocyst complex, has been identified as an interactor of GTP-bound Rab11 in mammals and Drosophila which shows its role in secretion in yeast and intracellular vesicle transport. Here, we report the expression patterns of Drosophila Sec15 (DSec15)transcript and Sec15 protein during Drosophila development. At early embryonic stages, a profound level of maternally loaded DSec15 transcript and protein is found. At cellular blastoderm cells (stage 5 embryos); the expression is seen in pole cells, apical membrane and sub-apical region. The transcript is predominantly accumulated in mesoderm, tracheal pits, gut, LE cells, trachea, and ventral nerve cord as development proceeds. While, a robust expression of Sec15 is seen in amnioserosa (AS), lateral epidermis (LAE), developing trachea, gut, ventral nerve cord and epithelial cells. During larval development, the transcript is also found in all imaginal discs with a distinguished accumulation in the morphogenetic furrow of eye disc, gut, proventriculus and gastric ceacae, garland cells/nephrocytes, malpighian tubules, ovary and testis. Further, we show that Sec15 co-localizes with Rab11 during Drosophila embryonic and larval development. Finally, using a genetic approach, we demonstrate that Sec15 interacts with Rab11 in producing blister during Drosophila wing development. © 2019 Elsevier Inc.PublicationArticle Shrinkage testimators for the variance of a normal distribution at single and double stages(1988) B.N. Pandey; H.J. Malik; Rakesh SrivastavaThis paper proposes some shrunken testimators at single and double stages for the variance of normal distribution when an initial estimate of σ2 is available in the form of point estimate σ02. The proposed testimators have been obtained by selecting different shrinkage factors useful in different situations. Expressions for bais, mean squared error, relative bias and relative efficiency have been derived. Comparisons of different proposed estimators have been made and it is shown that by taking the square of the shrinkage factor considered in Adke et al. (1987), the better estimator can be obtained when σ02 is in the vicinity of true value. © 1988.PublicationArticle Effect of exogenous melatonin on X-ray induced cellular toxicity in lymphatic tissue of Indian tropical male squirrel, Funambulus pennanti(2008) Shweta Sharma; Chandana Haldar; Shail K. ChaubePurpose: The radioprotective ability of melatonin was investigated in the Indian tropical rodent, Funambulus pennanti during its reproductively inactive phase (RIP) when peripheral melatonin is high and the animal is under the influence of environmental stresses. Materials and methods: Fifty male squirrels were divided into two sets of 25 each; with set 1 receiving 0.9% saline and set 2 receiving 25 μg melatonin/100 g body weight/day for four weeks during evening hours. Five saline-treated and five-melatonin treated squirrels were sacrificed at times of 4, 24, 48 and 72 hours following 2.06 Gy X-ray radiation. Remaining squirrels that were not exposed to X-ray were used as control and melatonin treated, respectively. Total leukocyte count (TLC) and lymphocyte count (LC) in peripheral blood and lipid peroxidation (LPO) status, superoxide dismutase (SOD) activity, total antioxidant status (TAS), apoptotic percentage on the basis of morphological changes and DNA fragmentation and caspase-3 activity were measured in the spleens of squirrels. Results: Peripheral blood and spleens with higher intrinsic levels of environmental and X-radiation induced free radical generation had inhibited TLC, LC, SOD activity and TAS and increased LPO and apoptosis. Melatonin pre-treatment significantly reduced and altered the changes brought on by X-radiation. Conclusion: Exogenous melatonin with its anti-apoptotic and antioxidant properties additively increased the immunity of the squirrels, by protecting their hematopoietic system and lymphoid organs against X-ray radiation induced cellular toxicity. © 2008 Informa UK Ltd.