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Role of beneficial microbial gene pool in mitigating salt/nutrient stress of plants in saline soils through underground phytostimulating signalling molecules

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Pedosphere 2023年第1期33卷 153-171页

作者： Shalini TIWARI Barkha SHARMA Neha BISHT lakshmi tewari Department of Microbiology College of Basic Science&HumanitiesG.B.Pant University of Agriculture&TechnologyPantnagarUttarakhand 263145India

Soil salinity diminishes soil health and reduces crop yield,which is becoming a major global *** stress is one of the primary stresses,leading to several other secondary stresses that restrict plant growth and soil *** major secondary stresses induced in plants under saline-alkaline conditions include osmotic stress,nutrient limitation,and ionic stress,all of which negatively impact overall plant *** stressed conditions,certain beneficial soil microflora are known to have evolved phytostimulating mechanisms,such as the synthesis of osmoprotectants,siderophores,1-aminocyclopropane-1-carboxylic acid(ACC)deaminase activity,phosphate solubilization,and hormone production,which enhance plant growth and development while mitigating nutrient *** soil-borne bacterial species such as Bacillus,Pseudomonas,and Klebsiella and fungal strains such as Trichoderma,Aspergillus,Penicillium,Alternaria,and Fusarium also aid in reducing salinity ***-solubilizing microorganisms also assist in nutrient acquisition via both enzymatic and non-enzymatic *** the case of enzymatic processes,they produce different enzymes such as alkaline phosphatases and phytases,whereas non-enzymatic processes produce organic acids such as gluconic,citric,malic,and oxalic *** native halotolerant/halophilic soil microbial gene pool with multifunctional traits and stress-induced gene expression can be developed as suitable bio-inoculants to enhance stress tolerance and optimize plant growth in saline soils.

关键词： abiotic stress crop improvement gene expression halotolerant microbial diversity phosphate solubilization plant growth promoting traits soil health

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Significance of pathological positive superior mesenteric/portal venous invasion in pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2016年第6期15卷 572-578页

作者： Mallika tewari Hepato Pancreatico Biliary and Gastrointestinal Division Department of Surgical OncologyInstitute of Medical SciencesBanaras Hindu University

BACKGROUND： Pancreaticoduodenectomy with superior mesenteric/portal venous resection for pancreatic ductal ad- enocarcinoma （PDAC） is frequently performed with no added morbidity or mortality in case of tumor abutment to the superior mesenteric or portal vein so as to obtain a margin negative resection. True histopathological portal vein invasion is found only in a small subset of such patients. The aim of this review aimed to discuss the significance of histopathological venous invasion in *** SOURCES： For this review available data was searched from PubMed and analyzed. No randomized trials have been published on this topic. RESULTS： Existing data on prognostic factors in histopathological venous invasion by PDAC are limited and recent studies indicate worse survival in this subgroup of patients. In addition, venous invasion in PDAC has been associated with large tumors, involved lymph nodes, perineural invasion and R1 resection. The survival of patients with portal venous re- section but without histologic venous invasion is reportedly better than those with histopathological venous invasion; though conflicting studies do exist on the subject. Some studies also relate the depth of venous invasion to prognosis after surgical resection of PDAC. CONCLUSIONS： Frank/＇histopathological＇ invasion of superior mesenteric/portal venous and R1 resection indicate a very poor survival. Such patients may be given the opportunity of benefit of neoadjuvant treatment.

关键词： pancreatic ductal adenocarcinoma superior mesenteric/portal venous invasion histologic venous invasion prognosis survival

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Carbon sequestration in Chir-Pine(Pinus roxburghii Sarg.) forests under various disturbance levels in Kumaun Central Himalaya

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Journal of Forestry Research 2014年第2期25卷 401-405页

作者： Harshit Pant Ashish tewari Department of Forestry & Environmental Sciences D.S.B. CampusKumaun University

We studied variations in tree biomass and carbon sequestration rates of Chir Pine （Pinus roxburghii. Sarg.） forest in three categories of forest disturbance, protected, moderately disturbed, and highly disturbed. In the first year, total biomass was ***-1 in highly disturbed site, 94.46 ***-1 in moderately disturbed forest, and 112.0 ***-1 in protected forest. The soil organic carbon in the top 20 cm of soil ranged from 0.63 to 1.2%. The total rate of carbon sequestration was 0.60 （t/ha）.a-lon the highly disturbed site, 1.03 （t/ha）a-1 on the moderately disturbed site, and 4.3 （t/ha）.a-1 on the protectedsite. Keywords： carbon sequestration, soil organic carbon （SOC）, disturbed forest, vegetation analysis, allometric equations

关键词： carbon sequestration soil organic carbon (SOC) disturbed forest vegetation analysis allometric equations

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Heartwood, sapwood and bark content of teak trees grown in Karnataka, India

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Journal of Forestry Research 2013年第4期24卷 721-725页

作者： Vindhya Prasad tewari K.M.Mariswamy Institute of Wood Science and Technology

We evaluated heartwood, sapwood and bark content in teak trees. A total of 27 sample plots were laid out in teak plantations raised by State Forest Department in Kamataka covering different age groups （11-36 years）, density （516-2061 trees/ha） and sites. From these planta- tions, a total of 130 trees were felled for estimating the yield and bark content in relation to diameter at breast height （DBH）, age and density. Bark content ranged from 22.2%-54.3%. Heartwood and sapwood con- tent were analyzed by sampling five trees each from two different planta- tions, one 30 years old at 553 ***-1 and the other 32 years old at 911 ***-1. The highest heartwood proportion of stem wood volume （over-bark） was 56.3% and the lowest was 37.1%.

关键词： diameter at breast height (DBH) age stand density heart-wood sapwood bark teak India

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Oxidative Stressand Antioxidant Responses in Young Leaves of Mulberry Plants Grown Under Nitrogen, Phosphorus or Potassium Deficiency

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Journal of Integrative Plant Biology 2007年第3期49卷 313-322页

作者： Rajesh Kumar tewari Praveen Kumar Parma Nand Sharma Department of Botany University of LucknowLucknow226007India

The aim of this study was to associate the generation of reactive oxygen species （ROS） with Induced antloxidant responses and disturbed cellular redox environment in the nitrogen-（N）, phosphorus-（P）, or potassium-（K） deftcient mulberry （Morus alba L. var. Kanva-2） plants. The indicators of oxidative stress and cellular redox environment and antioxldant defense-related parameters were analyzed. Oeficlency of N, P or K suppressed growth, accelerated senescence, and decreased concentrations of chloroplastic pigments and glutathione. Lipid peroxidation and activities of superoxide dismutase, ascorbate peroxidase and glutathione reductase were also increased in these N, P, or K deprived plants. Concentration of hydrogen peroxide Increased in plants deficient in N or P. Oeficlency of N or P particularly altered the cellular redox environment as indicated by changes in the redox couples, namely ascorbic acid/total ascorbate decreased in P-, glutathione sulfydryl/total glutathione decreased in N-, and Increased in P-deficient plants. Activity staining of native gels for superoxide dismutase revealed Increased activity as Indicated by Increased intensity of bands, and induction of few new isoforms in P- and K-deficient plants. Oifferences in the patterns of superoxide dismutase isoforms and redox status （ascorbic acid/total ascorbate and glutathlone sulfydryl/total glutathione） Indicate that N-, P-, or K-deficiency altered antioxidant responses to varying extents in mulberry plants.

关键词： antioxidants potassium-deficiency lipid peroxidation Morus alba mulberry nitrogen-deficiency oxidative stress phosphorus-deficiency reactive oxygen species

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A hybrid machine learning approach based study of production forecasting and factors influencing the multiphase flow through surface chokes

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Petroleum 2024年第2期10卷 354-371页

作者： Waquar Kaleem Saurabh tewari Mrigya Fogat Dmitriy A.Martyushev Department of Industrial and Manufacturing Engineering The Pennsylvania State UniversityUniversity ParkPA16802United States Department of Data Sciences Gyan Ganga Institute of Technology and SciencesJabalpur482002India Department of Petroleum and Geo-Engineering Rajiv Gandhi Institute of Petroleum Technology JaisBahadurpur229304India Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia

Surface chokes are widely utilized equipment installed on wellheads to control hydrocarbon flow *** correlations have been suggested to model the multiphase flow of oil and gas via surface ***,substantial errors have been reported in empirical fitting models and correlations to estimate hydrocarbon flow because of the reservoir's heterogeneity,anisotropism,variance in reservoir fluid characteristics at diverse subsurface depths,which introduces complexity in production ***,the estimation of daily oil and gas production rates is still challenging for the petroleum ***,hybrid data-driven techniques have been reported to be effective for estimation problems in various aspects of the petroleum *** paper investigates hybrid ensemble data-driven approaches to forecast multiphase flow rates through the surface choke(*** generalization and voting architectures),followed by an assessment of the impact of input production control ***,machine learning models are also trained and tested individually on the production data of hydrocarbon wells located in North *** engineering has been properly applied to select the most suitable contributing control variables for daily production rate *** study provides a chronological explanation of the data analytics required for the interpretation of production *** test results reveal the estimation performance of the stacked generalization architecture has outperformed other significant paradigms considered for production forecasting.

关键词： Machine learning Tree-based methods Stacking ensemble Multiphase flow Data analytics Wellhead choke variables

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Climate change effects in the Western Himalayan ecosystems of India: evidence and strategies

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Forest Ecosystems 2017年第3期4卷 232-240页

作者： Vindhya Prasad tewari Raj Kumar Verma Klaus von Gadow Himalayan Forest Research Institute Georg-August University Department of Forestry and Wood Science University of Stellenbosch

Background： The fragile landscapes of the Himalayan region are highly susceptible to natural hazards, and there is ongoing concern about current and potential climate change impacts. This study provides background information on India＇s Western Himalayas and reviews evidence of warming as well as variability in precipitation and extreme ***： Understanding and anticipating the impacts of climate change on Himalayan forest ecosystems and the services they provide to people are critical. Efforts to develop and implement effective policies and management strategies for climate change mitigation and adaptation requires particular new research initiatives. The various studies initiated and conducted in the region are compiled ***： Several new initiatives taken by the Himalayan Forest Research Institute in Shimla are described. This includes new permanent observational field studies, some with mapped trees, in high altitude transitional zones for continuous monitoring of vegetation response. We have also presented new strategies for mitigating potential climate change effects in Himalayan forest ***： Assessment of the ecological and genetic diversity of the Himalayan conifers is required to evaluate potential responses to changing climatic conditions. Conservation strategies for the important temperate medicinal plants need to be developed. The impact of climate change on insects and pathogens in the Himalayas also need to be assessed. Coordinated efforts are necessary to develop effective strategies for adaptation and mitigation.

关键词： Himalayan ecosystem Climate change New strategies High altitude New observational studies

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A relativistic model of stellar objects with core-crust-envelope division

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Research in Astronomy and Astrophysics 2021年第7期21卷 71-83页

作者： Ravindra K.Bisht Satyanarayana Gedela Neeraj Pant Neeraj tewari Department of Mathematics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematics SSJ CampusKumaun UniversityAlmora-263601India Department of Physics Lajpat Rai CollegeGhaziabad-201005India

In this work, we present a cogent and physically well-behaved solution for neutron stars envisaged with a core layer having quark matter satisfying the MIT-bag equation of state(Eo S), meso layer with Bose-Einstein condensate(BEC) matter satisfying modified BEC Eo S and an envelope having neutron fluid and Coulomb liquids satisfying quadratic Eo S. All the required physical and geometrical parameters like gravitational potentials, pressures, radial velocity, anisotropy, adiabatic index, mass function, compactification factor, and gravitational and surface redshift functions show a feasible trend and are continuous with smooth variation throughout the interior and across the regions of the ***, causality condition, energy conditions, static stability criterion(using Tolman-OppenheimerVolkoff equation) and Herrera cracking stability criterion are met throughout the star. The approach seems to be resulting in more realistic and accurate modeling of stellar objects, particularly realized by us for X-ray binary stars 4 U 1608–52(M = 1.7 M_⊙, R = 9.5 km) and SAX J1808.4–3658(M = 1.2 M_⊙,R = 7.2 km). Furthermore, we have ascertained that the continuity of the stability factor in all three regions of the stars demand a smaller core. As the core region of the star increases, the stability factor becomes discontinuous at all the interfaces inside the star.

关键词： stars:interiors stars:neutron Galaxy:stellar content

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Environmental Degradation Behavior of High-velocity Arc Sprayed FeCrBMnSi Alloy Coatings in a Coal Fired Boiler

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 602-612页

作者： V.N.Shukla R.Jayaganthan V.K.tewari Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee

FeCrBMnSi alloy coating on steel substrate（310S） was fabricated by a high-velocity arc spraying（HVAS） process. Degradation behavior of the coatings at temperatures of 700℃ and 900℃ in air and in the coal fired boiler at（700±10）℃ was studied. X-ray difraction（XRD） and scanning electron microscopy/energydisperse spectroscopy（SEM/EDS） were used to characterize the coating as well as to analyze the corrosion products for elucidating the corrosion *** exhibited dense and globular morphology and the splats were interconnected as evident from SEM analysis. The maximum microhardness of the coating was found to be 630–1060 HV. The FeCrBMnSi alloy coating has imparted necessary resistance to oxidation and showed good adherence to the 310S substrate during the exposures with no tendency for spallation of its oxide scale.

关键词： HVAS process Coating Microhardness Oxidation Erosion

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Studies on induction hardening of powder-metallurgy-processed Fe–Cr/Mo alloys

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International Journal of Minerals,Metallurgy and Materials 2017年第8期24卷 918-925页

作者： Sandeep Chauhan Vikas Verma Ujjwal Prakash P.C.tewari Dinesh Khanduja Department of Mechanical Engineering National Institute of Technology Department of Metallurgical & Materials Engineering Indian Institute of Technology

Induction hardening of dense Fe–Cr/Mo alloys processed via the powder-metallurgy route was studied. The Fe-3Cr-0.5Mo, Fe-1.5Cr-0.2Mo, and Fe-0.85 Mo pre-alloyed powders were mixed with 0.4wt%, 0.6wt%, and 0.8wt% C and compacted at 500, 600, and 700 MPa, respectively. The compacts were sintered at 1473 K for 1 h and then cooled at 6 K/min. Ferrite with pearlite was mostly observed in the sintered alloys with 0.4wt% C, whereas a carbide network was also present in the alloys with 0.8wt% C. Graphite at prior particle boundaries led to deterioration of the mechanical properties of alloys with 0.8wt% C, whereas no significant induction hardening was achieved in alloys with 0.4wt% C. Among the investigated samples, alloys with 0.6wt% C exhibited the highest strength and ductility and were found to be suitable for induction hardening. The hardening was carried out at a frequency of 2.0 kHz for 2–3 s. A case depth of 2.5 mm was achieved while maintaining the bulk(interior) hardness of approximately HV 230. A martensitic structure was observed on the outer periphery of the samples. The hardness varied from HV 600 to HV 375 from the sample surface to the interior of the case hardened region. The best combination of properties and hardening depth was achieved in case of the Fe-1.5Cr-0.2Mo alloy with 0.6wt% C.

关键词： Fe–Cr/Mo alloys powder metallurgy sintered density tensile strength induction hardening case depth

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