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Journal of Environmental Sciences 2017年第2期29卷 160-169页

作者： Raja Kumar alok sinha Department of Environmental Science&Engineering Indian School of MinesDhanbad 826004JharkhandIndia

Influence of common dye-bath additives, namely sodium chloride, ammonium sulphate,urea, acetic acid and citric acid, on the reductive decolouration of Direct Green 1 dye in the presence of Fe0 was investigated. Organic acids improved dye reduction by augmenting Fe0 corrosion, with acetic acid performing better than citric acid. Na Cl enhanced the reduction rate by its ‘salting out’ effect on the bulk solution and by Cl-anion-mediated pitting corrosion of iron surface.（NH4）2SO4induced ‘salting out’ effect accompanied by enhanced iron corrosion by SO42-anion and buffering effect of NH4＋ improved the reduction ***, at 2 g/L（NH4）2SO4concentration, complexating of SO42-with iron oxides decreased Fe0 reactivity. Urea severely compromised the reduction reaction, onus to its chaotropic and‘salting in’ effect in solution, and due to it masking the Fe0 surface. Decolouration obeyed biphasic reduction kinetics（R2〉 0.993 in all the cases） exhibiting an initial rapid phase,when more than 95% dye reduction was observed, preceding a tedious phase. Maximum rapid phase reduction rate of 0.955/min was observed at p H 2 in the co-presence of all dye-bath constituents. The developed biphasic model reckoned the influence of each dye-bath additive on decolouration and simulated well with the experimental data obtained at pH 2.

关键词： Biphasic kinetics/model Direct Green 1 Dye-bath additives Fe0

Signal convergence through the lenses of MAP kinases： paradigms of stress and hormone signaling in plants

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Frontiers in Biology 2013年第1期8卷 109-118页

作者： Kundan KUMAR Dhammaprakash Pandhari WANKHEDE alok Krishna sinha Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 USA National Institute of Plant Genome Research Aruna Asaf Ali Road New Delhi 110067 India

Common mechanisms plants use to translate the external stimuli into cellular responses are the activation of mitogen-activated protein kinase （MAPK） cascade. These MAPK cascades are highly conserved in eukaryotes and consist of three subsequently acting protein kinases, MAP kinase kinase kinase （MAPKKK）, MAP kinase kinase （MAPKK） and MAP kinase （MAPK） which are linked in various ways with upstream receptors and downstream targets. Plant MAPK cascades regulate numerous processes, including various environmental stresses, hormones, cell division and developmental processes. The number of MAPKKs in Arabidopsis and rice is almost half the number of MAPKs pointing important role of MAPKKs in integrating signals from several MAPKKKs and transducing signals to various MAPKs. The cross talks between different signal transduction pathways are concentrated at the level of MAPKK in the MAPK cascade. Here we discussed the insights into MAPKK mediated response to environmental stresses and in plant growth and development.

关键词： environmental stresses abiotic stress biotic stress mitogen-activated protein kinase kinase MAPKK mitogen-activated protein kinase MAPK plant signaling

Establishment of a Photoautotrophic Cell Suspension Culture of Arabidopsis thaliana for Photosynthetic, Metabolic, and Signaling Studies

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Molecular Plant 2012年第2期5卷 524-527页

作者： Christine Hampp Andreas Richter Sonia Osorio Günther Zellnig alok Krishna sinha Alexandra Jammer Alisdair R. Fernie Bernhard Grimm Thomas Roitsch Julius-von-Sachs-Institut fuer Biowissenschaften UniversitaetWuerzburgJulius-von-Sachs-Platz 297082 WuerzburgGermany Institute of Biology/Plant Physiology Humboldt UniversityPhilippstr.13Building 1210115 Berlin Max-Planck Institute of Molecular Plant Physiology Am Mühlenberg 114476 Potsdam-GolmGermany Institut fuer Pflanzenwissenschaften Schubertstr.51A-8010 GrazAustria National Institute of Plant Genome Research PB No.10531Aruna Asaf Ali RoadNew Delhi–110067India

Dear Editor, Plant cell suspension cultures have been used as model systems to circumvent the problems associated with the analyses of a multi-factorial plant that is composed of multiple tissue and cell types exposed to diverse signals. A number of plant suspension cultures have proven to be valuable to study various topics including defense response, secondary metabolite formation, ion transport, gene regulation, and signal duction （Roitsch and sinha, 2002 and references therein）. However, most cultures reported to date, including the cultures from model species such as Arabidopsis （Christie and Jenkins,

关键词：基因离子转运拟南芥属社会控制正式血气分析胰岛素铍

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled alok Timothy G.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Post-Translational Derepression of Invertase Activity in Source Leaves via Down-Regulation of Invertase Inhibitor Expression Is Part of the Plant Defense Response

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Molecular Plant 2010年第6期3卷 1037-1048页

作者： Katharina B. Bonfig Andrea Gabler Uwe K. Simon Nora Luschin-Ebengreuth Martina Hatz Susanne Berger Naseem Muhammad Jurgen Zeier alok K. sinha Thomas Roitsch Julius-von-Sachs-Institut fuer Biowissenschaften Lehrstuhl for Pharmazeutische Biologie Universitaet Wuerzburg Julius-von-Sachs-Platz 2 97082 Wuerzburg Germany Institute of Plant Sciences Department of Plant Physiology University of Graz 8010 Graz Austria Zentrum for rnedizinische Grundlagenforschung (ZMF) Medizinische Universitat Graz Stiftingtalstraβe 24 A-8010 Graz Department of Biology Plant Biology Section University of Fribourg Route Albert Gockel 3 CH-1700 Fribourg Switzerland National Institute for Plant Genome Research Aruna Asaf Ali Road New Delhi 110067 India

There is increasing evidence that pathogens do not only elicit direct defense responses, but also cause pronounced changes in primary carbohydrate metabolism. Cell-wall-bound invertases belong to the key regulators of carbohydrate partitioning and source-sink relations. Whereas studies have focused so far only on the transcriptional induction of invertase genes in response to pathogen infection, the role of post-translational regulation of invertase activity has been neglected and was the focus of the present study. Expression analyses revealed that the high mRNA level of one out of three proteinaceous invertase inhibitors in source leaves of Arabidopsis thaliana is strongly repressed upon infection by a virulent strain of Pseudomonas syringae pv. tomato DC3000. This repression is paralleled by a decrease in invertase inhibitor activity. The physiological role of this regulatory mechanism is revealed by the finding that in situ invertase activity was detectable only upon infection by P. syringae. In contrast, a high invertase activity could be measured in vitro in crude and cell wall extracts prepared from both infected and non-infected leaves. The discrepancy between the in situ and in vitro invertase activity of control leaves and the high in situ invertase activity in infected leaves can be explained by the pathogen-dependent repression of invertase inhibitor expression and a concomitant reduction in invertase inhibitor activity. The functional importance of the release of invertase from post-translational inhibition for the defense response was substantiated by the application of the competitive chemical invertase inhibitor acarbose. Posttranslational inhibition of extracellular invertase activity by infiltration of acarbose in leaves was shown to increase the susceptibility to P. syringae. The impact of invertase inhibition on spatial and temporal dynamics of the repression of photosynthesis and promotion of bacterial growth during pathogen infection supports a

关键词： Acarbose Arabidopsis defense responses invertase inhibitor protein invertase plant-microbe interactions Pseudomonas syringae.

Production and characterisation of new bioresorbable radiopaque Mg–Zn–Y alloy to improve X-ray visibility of polymeric scaffolds

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Journal of Magnesium and Alloys 2022年第6期10卷 1694-1703页

作者： alok Srivastava Naresh Bhatnagar Mechanical Engineering Department Indian Institute of TechnologyDelhiIndia

For the medical diagnosis,radiopaque materials(RM)made from high specific gravity elements like Pt,Au,Ta,Iodine,Bromine are either attached or blended or coated on an implant to makes it detectable under X-ray/Fluoroscopy/*** facilitate the surgeon in an operation theatre to position an implant during the ***,RM are non-degradable,thus in case of biodegradable implants,it may detach from the body and accumulate in vital organ cause serious health ***,a new bioresorbable radiopaque material(BRM)was produced by alloying the high specific gravity elements Zn(35%w/w)and Y(4%w/w)with Mg *** this alloy,three main phases were identified,alpha Mg,Mg_(7)Zn_(3)and icosahedral quasicrystalline I-phase Mg3Zn6Y,which reinforce the Mg ***,BRM was powdered to a size of less than 25 microns and blended in different ratios with bioresorbable poly-L-lactic acid(PLLA)for fabricating PLLA/BRM *** microparticles were uniformly distributed and interfacial bonded with the *** X-ray was passed through bio-composite to captureμCT radiograph for evaluating linear attenuation co-efficient(μ)and optical density(OD).Thermal analysis reveals that BRM particles act as a nucleating site and enhance the crystallinity of the polymeric *** the In Vitro accelerated degradation study,the alkaline nature of BRM neutralise the acidity of PLLA and balance the pH of the body fluid to reduce the inflammatory reactions,but this compromises the stability of the polymer as it increases the decomposition rate.

关键词： Magnesium alloys X-ray Quasicrystal Polymer matrix composites Radiopacity

Modelling and analysis of COVID-19 epidemic in India

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Journal of Safety Science and Resilience 2020年第2期1卷 135-140页

作者： alok Tiwari Department of Energy Science and Engineering IIT BombayMumbai 400076India

COVID-19 epidemic is declared as the public health emergency of international concern by the World Health Organisation in the last week of March *** disease originated from China in December 2019 has already caused havoc around the world,including *** first case in India was reported on 30th January 2020,with the cases crossing 4 million on the day paper was *** pandemic has caused more than 80,000 fatalities with 3 million *** lockdown of the nation for two months,immediate isolation of infected cases and app-based tracing of infected are some of the proactive steps taken by the *** a better understanding of the evolution of COVID-19 in the world,study on evolution and growth of cases in India could not be *** understand the same,one of the compartment model:Susceptible-Infectious-Quarantined-Recovered(SIQR)is *** rate and doubling rate of the total reported positive cases in the country had crossed 75%and 25 days,*** is also estimated that there is a strong positive correlation between testing rate and detection of new cases up to 6 million tests per *** the SIQR modelling effective reproduction number,epidemic doubling rate and infected to quarantined ratio is determined to check the temporal evolution of the pandemic in the *** reproduction number that was at its peak during first half of the April is gradually converging to *** is also estimated using this model that with each detected cases in India,there could be 10-50 undetected *** every mathematical model,this model also has some *** make this model more robust,a technique with weighted parameter that can avoid a person with a strong immune system to be equally vulnerable to the infection,can be worked *** learning algorithms can also be used to train our model with the data of other countries to make the analysis and prediction more precise and accurate.

关键词： Mathematical modelling SIQR COVID 19 Reproduction number India

Acclimation and Tolerance Strategies of Rice under Drought Stress

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Rice science 2015年第4期22卷 147-161页

作者： Veena PANDEY alok SHUKLA Department of Plant Physiology College of Basic Sciences and HumanitiesGovind Ballabh Pant University of Agriculture & Technology

Rice （Oryza sativa L.） is an important food crop and requires larger amount of water throughout its life cycle as compared to other crops. Hence, water related stress cause severe threat to rice production. Drought is a major challenge limiting rice production. It affects rice at morphological （reduced germination, plant height, plant biomass, number of tillers, various root and leaf traits）, physiological （reduced photosynthesis, transpiration, stomatal conductance, water use efficiency, relative water content, chlorophyll content, photosystem II activity, membrane stability, carbon isotope discrimination and abscisic acid content）, biochemical （accumulation of osmoprotectant like proline, sugars, polyamines and antioxidants） and molecular （altered expression of genes which encode transcription factors and defence related proteins） levels and thereby affects its yield. To facilitate the selection or development of drought tolerant rice varieties, a thorough understanding of the various mechanisms that govern the yield of rice under water stress condition is a prerequisite. Thus, this review is focused mainly on recent information about the effects of drought on rice, rice responses as well as adaptation mechanisms to drought stress.

关键词： rice water drought stress yield attribute morphological characteristic physiological characteristic biochemical characteristic molecular level

Dual-Core Photonic Crystal Fiber Plasmonic Refractive Index Sensor: A Numerical Analysis

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Photonic Sensors 2019年第2期9卷 151-161页

作者： alok Kumar PAUL Ajay Krishno SARKAR Department of Electrical & Electronic Engineering Rajshahi University of Engineering & Technology Rajshahi-6204 Bangladesh

A numerical analysis on dual core photonic crystal fiber (DC-PCF) based surface plasmon resonance (SPR) refractive index sensor is presented. The guiding parameters and required sensing performances are examined with finite element method (FEM) based software under MATLAB environment. According to simulation, it is warranted that the proposed refractive index sensor offers the maximum amplitude sensitivity of 554.9 refractive index unit (RIU-1) and 636.5 RIU 1 with the maximum wavelength sensitivity of 5800nm/RIU and 11 500nm/RIU, and the sensor resolutions of 1.72 ×10^-5RIU and 8.7× 10^-6 RIU, at analyte refractive index (RI) of 1.40 for x- and y-polarized modes, respectively. As the sensing performance in different wavelength ranges is quite high, the proposed sensor can be used in simultaneous detection for different wavelength ranges. Therefore, the proposed device is of a suitable platform for detecting biological, chemical, biochemical, and organic chemical analytes.

关键词： Photonic crystal fiber biosensor refractive index sensor finite element method plasmonic material

Powder mixed electrochemical discharge process for micro machining of C103 niobium alloy

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Defence Technology（防务技术） 2023年第8期26卷 84-101页

作者： Niladri Mandal Nitesh Kumar alok Kumar Das Defence Research&Development Laboratory(DRDL)-DRDO HyderabadIndia Department of Mechanical Engineering Indian Institute of Technology(ISM)DhanbadIndia

This work demonstrates the viability of the powder-mixed micro-electrochemical discharge machining(PMECDM) process to fabricate micro-holes on C103 niobium-based alloy for high temperature *** processes are involved simultaneously *** erosion,chemical etching,and abrasive grinding for removal of material while the classical electrochemical discharge machining process involves double actions *** erosion,and chemical *** powder-mixed electrolyte process resulted in rapid material removal along with a better surface finish as compared to the classical microelectrochemical discharge machining(MECDM).Further,the results are optimized through a multiobjective optimization approach and study of the surface topography of the hole wall surface obtained at optimized *** the selected range of experimental parameters,PMECDM shows a higher material removal rate(MRR) and lower surface roughness(R_(a))(MRR:2.8 mg/min and R_(a) of 0.61 μm) as compared to the MECDM process(MRR:2.01 mg/min and corresponding Raof 1.11 μm).A detailed analysis of the results is presented in this paper.

关键词： Micro-electrochemical discharge machining C103 niobium alloy Surface integrity Material removal rate Hybrid powder mixed ECDM