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Open Journal of Physical Chemistry 2014年第3期4卷 81-97页

作者： kinshuk raj srivastava Susheel Durani Department of Chemistry Indian Institute of Technology Bombay Mumbai India Department of Physics and Astronomy Michigan State University East Lansing USA

A poly-L β-hairpin bent stereochemically as a boat-shaped protein of mixed-L,D structure is scrutinized in basis of ordering as minimum of energy specific for its sequenceand solvent. The model suitable for the scrutiny is accomplished by design. A terminally-blocked oligoalanine is nucleated overDPro6-Gly7 and DPro6-LAsp7 dipeptide structures as a twelve-residue β-hairpin and bent stereochemically as a boat-shaped fold. The structure is inverse designed with side chains suitable to bind substrate p-nitophenyl phosphate, a surrogate substrate of acetyl choline and CO2. The designed sequences were proven by spectroscopy and molecular dynamics to order with solvent effects of water and display high binding affinity for the substrate. One of the proteins and a cognate oligoalanine are evolved with molecular dynamics to equilibrium in a solvent bath of water. Molecular dynamics studies establish that heteropolypeptide well ordered as β-hairpin fold and cognate oligoalanine as an ensemble of hairpin-like folds in water. The ordering of cognate oligoalanine as ensembles of hairpin-like folds manifests combined role of water as strong dielectric and weak dipolar solvent of peptides. The roles of stereochemistry and chemical details of sequence in defining polypeptides as energy minima under specific effect of solvent are illuminated and have been discussed.

关键词： Protein Folding Protein Stereochemistry β-Hairpin Polyalanine Model Solvent Effects

A 2000 Year Multi-Proxy Evidence of Natural/Anthropogenic Influence on Climate from the Southwest Coast of India

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Journal of Earth Science 2020年第5期31卷 1029-1044页

作者： M.C.Manoj Jyoti srivastava Prem raj Uddandam Biswajeet Thakur Birbal Sahni Institute of Paleosciences 53 University RoadL ucknowUttar Pradesh 226007India Banaras Hindu University VaranasiUttar PradeshIndia

The last millennium climate reconstructions are complex and limit our understanding of the mechanisms behind environmental and climate variability. We present multi-proxy centennial-scale records from the Cherai, southwest India. The last 2000 cal yr AD record suggests a complex environmental condition that prevailed at the depositional site augmenting the role of natural as well as anthropogenic agents. Increased elemental variations and indices values indicate stronger weathering, presumably wetter conditions and intense precipitation. Provenance studies suggest diverse sources and the main composition fall close to the Charnockite and Gneissic composition. Multi-proxy data suggests that a shift towards wetter climatic conditions, which occurred from 910 to 1230 cal yr AD. The core also records a shift towards the drier conditions that started around 1230 cal yr AD with a loss in vegetation diversity. The pollution load index values suggest that the overall study area falls in moderate contamination levels, which are also substantiated with the diatom data indicating human influence in the natural habitat during the deposition time. The present study reveals that the enhanced Cd and As concentration is due to strong anthropogenic influence. We compared the multi-proxy record with other continental and marine palaeoclimatic records to explore global and/or regional trends in climate variability during the last 2000 years.

关键词： estuaries monsoon provenance vegetation clmate contamination

Infuence of gut microbiome on the human physiology

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Systems Microbiology and Biomanufacturing 2022年第2期2卷 217-231页

作者： Aakriti srivastava Muhil raj Prabhakar Anee Mohanty Sumer Singh Meena Department of Biotechnology Dr.B.R.Ambedkar National Institute of TechnologyJalandharPunjab 144011India

Trillions of microbes harbor the gastrointestinal tract and co-exist peacefully with the human *** diversity and composition among individuals depend upon human age,diet,and environmental *** dynamic population of the gut microbiome,majorly consisting of Bacteroidetes and Firmicutes,forms a complex ecological *** collective metabolic activities and interaction of gut microbiota with the host exert a marked infuence on human *** gut microbiota help to perform various functions,such as maintenance of intestinal mucosal integrity,production of antimicrobial peptides,protection against foreign invaders,and immunity *** addition,they also provide essential nutrients,such as enzymes and vitamins,and also take part in metabolite synthesis,which infuences both cognitive and behavioral functions of the human *** equilibrium among gut microorganisms,and between the microbes and intestinal interface of the host allows the maintenance of benefcial *** alteration or dysbiosis in gut microbial composition,due to a sedentary lifestyle or intake of an unbalanced diet,plays a crucial role in the development of diseases like systemic infammation,insulin resistance,auto-immune and metabolic *** review summarizes our current understanding of the gut microbial organization,its importance in the fundamental biological processes and the pathogenesis of various human diseases and infections,and also the prognostic,diagnostic,and therapeutic potential of the gut microbiota.

关键词： Gut microbiota Microorganisms Gastrointestinal tract Digestive system Nutrition Metabolism

Trends in Gunshot Residue Detection by Electrochemical Methods for Forensic Purpose

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Journal of Analysis and Testing 2021年第3期5卷 258-269页

作者： Abhimanyu Harshey Ankit srivastava Tanurup Das Kriti Nigam raj Shrivastava Vijay K.Yadav Dr.A.P.J.Abdul Kalam Institute of Forensic Science and Criminology Bundelkhand UniversityJhansi 284128India State Forensic Science Laboratory Sagar 470002India

Gunshot Residue(GSR)has been a subject of interest for the forensic *** analytical contributions towards the GSR analysis have been ***,portability,cost-effectiveness,speed,*** such factors of electrochemical methods that have attracted the researchers across the globe to test the applicability of these as a potential analytical tool for forensic evaluation of *** the development of scientific technology,efforts have been made towards the handheld device for the on-field analysis of ***,chemometric treatment of data generated from the electrochemical analysis of GSR has offered more effective *** makes the analysis more conclusive and minimizes the chances of false-positive *** will be very fruitful to anticipate the analytical potential of electrochemical tools for GSR *** article reviews the research progress towards the development of electrochemical sensor for GSR detection reported during 2013-2020 along with challenges and future perspectives.

关键词： GSR(gunshot residue) Forensics Electrochemical sensing Voltammetry Amperometry

Artificial Neural Network Modeling for Sorption of Cadmium from Aqueous System by Shelled Moringa Oleifera Seed Powder as an Agricultural Waste

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Journal of Water Resource and Protection 2010年第4期2卷 339-344页

作者： Abhishek Kardam Kumar Rohit raj Jyoti Kumar Arora Man Mohan srivastava Shalini srivastava 不详

A two-layer Artificial Neural Network (ANN) model was developed to predict the removal efficiency of Cd(II) ions from aqueous solution using shelled Moringa Oleifera seed (SMOS) powder. Batch experiments re-sulted into standardization of optimum conditions: biomass dosage (4.0 g), Cd(II) concentration (25 mg/L) volume (200 mL) at pH 6.5. A time of forty minutes was found sufficient to achieve the equilibrium. The ANN model was designed to predict sorption efficiency of SMOS for target metal ion by combining back propagation (BP) with principle component analysis. A sigmoid axon was used as transfer function for input and output layer. The Levenberg-Marquardt algorithm (LMA) was applied, giving a minimum mean squared error (MSE) for training and cross validation at the ninth place of decimal.

关键词： Artificial Neural Network Biosorption SMOS Cd(II) Removal

Neural Network Modeling for Ni(II) Removal from Aqueous System Using Shelled Moringa Oleifera Seed Powder as an Agricultural Waste

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Journal of Water Resource and Protection 2010年第4期2卷 331-338页

作者： Kumar Rohit raj Abhishek Kardam Jyoti Kumar Arora Man Mohan srivastava Shalini srivastava 不详

A single-layer Artificial Neural Network (ANN) model was developed to predict the removal efficiency of Ni(II) ions from aqueous solution using shelled Moringa Oleifera seed (SMOS) powder. Batch experiments resulted into standardization of optimum conditions: biomass dosage (4.0 g), Ni(II) concentration (25 mg/L) volume (200 mL) at pH 6.5. A time of forty minutes was found sufficient to achieve the equilibrium. The ANN model was designed to predict sorption efficiency of SMOS for target metal ion by combining back propagation (BP) with principle component analysis. A sigmoid axon was used as transfer function for input and output layers. The Levenberg–Marquardt Algorithm (LMA) was applied, giving a minimum mean squared error (MSE) for training and cross validation at the ninth place of decimal.

关键词： Artificial Neural Networks Biosorption Moringa Oleifera Ni(II) Removal

Metabolic Changes during Acclimation and Hardening to Heat and Drought Stress in Zaprionus indianus

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Advances in Entomology 2022年第1期10卷 110-133页

作者： Aditya Moktan Tamang Ravi Parkash raj Kamal srivastava Padmasana Singh Department of Zoology Indira Gandhi National Tribal University Amarkantak India Department of Genetics Maharshi Dayanand University Rohtak India

The survival ability of insects can be limited with the changes in the levels of energy metabolites under stressful conditions but only a few studies have considered the plastic effects of heat and related climatic factors relevant to tropical habitats. The objectives of our study were to determine whether adults of Zaprionus indianus are capable of rapid heat hardening (RHH) and rapid desiccation hardening (RDH) and to compare its benefits with heat acclimation (HA) and desiccation acclimation (DA). Adult flies reared under season-specific simulated conditions were subjected to 38°C for RHH and 32°C for HA, while 5% relative humidity (RH) was maintained for RDH and 40% RH for DA. Stress-induced effects of heat and desiccation on the levels of five metabolites namely cuticular lipids (CL), total body lipids (TBL), protein, proline, and carbohydrates were then estimated by biochemical method. Different duration of heat hardening and acclimation led to more accumulation of CL whereas different durations of desiccation hardening and acclimation revealed less accumulation. In contrast, there was an accumulation of carbohydrates and protein under desiccation hardening and acclimation whereas there was the utilization of carbohydrates and protein under heat hardening and acclimation. However, mixed results were observed on the level of proline and TBL under both heat and desiccation stress. These stress-triggered changes in the levels of various metabolites suggest a possible link between heat and desiccation tolerance. Hence, these compensatory changes in the level of various metabolit

关键词： Zaprionus indianus Rapid Heat Hardening Heat Acclimation Rapid Desiccation Hardening Desiccation Acclimation

Genetic Variability and Elite Line Selection for High Essential Oil and Nepetalactone Content in Catmint (Nepeta catariaL.)

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American Journal of Plant Sciences 2021年第7期12卷 1135-1154页

作者： Abhilasha srivastava Soni Gupta Swati Singh Ram Swaroop Verma Ramesh Kumar srivastava Anil Kumar Gupta raj Kishori Lal Academy of Scientific and Innovative Research (AcSIR) Ghaziabad India Division of Plant Breeding and Genetic Resource Conservation CSIR—Central Institute of Medicinal and Aromatic Plants P.O. CIMAP Lucknow India Phytochemistry Division CSIR—Central Institute of Medicinal and Aromatic Plants P.O. CIMAP Lucknow India Technology and Business Development Division CSIR—Central Institute of Medicinal and Aromatic Plants P.O. CIMAP Lucknow India

Nepeta cataria L., commonly known as catmint or catnip, belongs to the family “Lamiaceae” and is indigenous to Europe and Asia. The essential oil of this species is known for the richness and diversity of nepetalactones (NPL) which are used as mosquito/insect repellents in perfumery and cosmetic industries. Reports on Indian catmint germplasm are very meager and warrants exploration of its commercial potential as a natural, non-toxic source of insect repellents. With this objective, commercial open-pollinated seeds of catmint collected from its native, temperate habitat in Himalayas were introduced in the tropical plains. Subsequent to adaptation to a new zone we were able to isolate nineteen individual plants based on plant growth. Hydrodistillation of the fresh herb yielded essential oil in the range of 0.01% to 0.2%. Gas Chromatography (GC) and GC-Mass Spectrometry (GC-MS) analyses of the oil revealed the dominance of monoterpene hydrocarbon, namely, 4aα,7α,7aα NPL (1) isomer (84%). The other two isomers of nepetalactone, 4aα,7α,7aβ NPL (2) and 4aα,7β,7aα NPL (3) were also present, although in very less amounts (1.0% and 1.6%, respectively). Sesquiterpenes identified were α-humulene (traces), (

Hematological, antioxidant and protective performance of Usnea longissima on chemical induced hepatotoxicity in experimental animals

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Journal of Coastal Life Medicine 2017年第5期5卷 224-232页

作者： Pritt Verma Shravan Kumar Paswan Abhisek raj Virendra Nath Ramesh Kumar Gupta Shikhar Verma Sajal srivastava ChandanaVenketshwara Rao Pharmacognosy and Ethnopharmacology Division CSIR-National Botanical Research InstituteLucknowIndia Amity Institute of Pharmacy Amity UniversityLucknowIndia Department of Pharmaceutical Sciences Central University of RajasthanRajasthanIndia Sherwood College of Pharmacy Barabanki-225001India

Objective: To investigated the hematological, antioxidant and protective performance of Usnea longissima (U. longissima) on CCl4 induced hepatotoxicity in experimental animals. Methods: Hepatotoxicity was induced by CCl4 (1 mL/kg body weigt 1:1 CCl4 i.p.), ethanolic U. longissima extracts at a doses (200 and 400 mg/kg body weigt) were administered to and compared with Silymarin (25 mg/kg body weigt) and hematological, antioxidant and enzymatic, non-enzymatic parameters were assessed through the liver functions test. All the observation was also supplemented with histopathological examination of liver sections. Results: Phytochemical investigation showed that ethanolic extract contains poly phenolic compounds tannins, flavonoids, alkaloids and saponins and acute toxicity study shows that ethanolic extract was safe up to 2000 mg/kg body weight. The toxicant induced a rise in the plasma enzyme levels of ALT, AST, ALP and total bilirubin level. This increased level was significantly decreased by the extract at 400 mg/kg body weight than 200 mg/kg body weight. The animals were prevented (partly or fully) which was showed in the histopathological changes using ethonolic U. longissima extract. Conclusions: The outcome of this study reveals that, there is a powerful antioxidant and hepatoprotective activity of U. longissima. It is believed that the present constituents are responsible for courting the hepatic disease and alternative components have the power to act as free radical scavenging properties.

关键词： Usnea longissima Carbon tetra chloride (CCl4) Hematological Antioxidant Histopathological

用CO₂、产出气及烟道气提高重油采收率的效果对比

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石油石化节能 2000年第2期 1-6页

作者： raj K.srivastava 莫增敏石家雄纪常杰不详新疆吐哈石油勘探开发研究院大庆油田设计院

加拿大及世界其它各地的大量重油油藏均为薄边际型油藏 ,不适于用热采方法 ,非混相气驱是提高这类油藏原油采收率的最好方法。本文对注CO2 、产出气及烟道气这三种气体提高重油采收率的适用性和效果进行了评价 ,对实验室研究结果进行了... 详细信息

加拿大及世界其它各地的大量重油油藏均为薄边际型油藏 ,不适于用热采方法 ,非混相气驱是提高这类油藏原油采收率的最好方法。本文对注CO2 、产出气及烟道气这三种气体提高重油采收率的适用性和效果进行了评价 ,对实验室研究结果进行了讨论。实验室研究包括压力 /体积 /温度 (PVT)研究和岩心驱替试验。被研究的气体为烟道气 (N2 中含摩尔浓度 1 5%的CO2 )、产出气 (CH4中含摩尔浓度1 5%的CO2 )和纯CO2 。试验所用重油采自位于加拿大萨斯喀彻温Lloydminster地区的Senlac油藏。PVT研究表明 ,通过注气开采Senlac重油的主要机理是降低原油粘度。纯CO2 为最佳开采剂 ,其次是产出气。岩心驱替结果证实了这些发现。然而 ,产出气和烟道气也是很有效的驱替剂 ,在注烟道气或产出气中产出的油主要是两个竞争机理———由N2 或CH4产生的游离气机理和由CO2 产生的溶解机理的综合作用的结果。后者在CO2 驱中起主要作用。

关键词：提高采收率重油油藏实验驱替剂