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Overexp.ession of asp.n sucrose synthase gene p.omotes growth and develop.ent of transgenic Arabidop.is p.ants

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Advances in Bioscience and Biotechnology 2010年第5期1卷 426-438页

作者： Fuyu Xu chandrashekhar p. joshi 不详

In p.ants, sucrose synthase (SUS) enzymes catalyze conversion of sucrose into fructose and UDp.glucose in the p.esence of UDp. To investigate the imp.ct of overexp.ession of heterologous SUS on the growth and develop.ent of Arabidop.is, we transformed Arabidop.is p.ants with an overexp.ession vector containing an asp.n SUS gene (p.rSUS1). The genomic p.R confirmed the successful integration of p.rSUS1 transgene in the Arabidop.is genome. p.rSUS1 exp.ession in transgenic Arabidop.is p.ants was confirmed by RT-p.R. The SUS activity was dramatically increased in all transgenic lines examined. The three selected transgenic p.rSUS1 lines exhibited faster growth and flowered about 10 days earlier comp.red to untransformed controls, and also p.ssessed 133%, 139%, and 143% SUS activity comp.red to controls. Both fresh weights and dry biomass yields of the whole p.ants from these three selected transgenic lines were significantly increased to 125% of the controls. Transgenic p.rSUS1 lines also had a higher tolerance to higher concentration of sucrose which was reflective of the increased SUS activity in transgenic versus wild-typ. p.ants. The growth differences between wild-typ. and transgenic p.ants, either in root and hyp.cotyl length or in fresh and dry weight of whole p.ant, became more p.onounced on the media containing higher sucrose concentrations. Taken together, these results showed that the early flowering, faster growth and increased tolerance to higher sucrose in transgenic lines were caused by the genome integration and constitutive exp.ession of the asp.n p.rSUS1 gene in transgenic Arabidop.is.

关键词： Arabidop.is Asp.n Trees (p.p.lus Tremuloides) Over-Exp.ession Sucrose Synthase (SUS) SUS Enzyme Activity

In vitro demonstration of interactions among zinc-binding domains of cellulose synthases in Arabidop.is and asp.n

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Advances in Bioscience and Biotechnology 2010年第3期1卷 152-161页

作者： Fuyu Xu chandrashekhar p. joshi 不详

p.ant cellulose synthases (CesAs) are the key enzymes necessary for cellulose biosynthesis. In Arabidop.is, two distinct group. of three CesAs each are necessary for cellulose synthesis during p.imary and secondary cell wall formation. It has also been suggested that such three CesAs interact with each other to form p.asma-membrane bound rosette comp.exes that are functional during cellulose p.oduction. However, in vivo demonstration of such assemblies of three CesAs into rosettes has not been p.ssible. We used yeast two-hybrid assays to demonstrate the p.ssible interactions among several CesAs from Arabidop.is and asp.n via their N-terminal zinc-binding domains (ZnBDs). While strong p.sitive interactions were detected among ZnBDs from secondary wall associated CesAs of both Arabidop.is and asp.n, the intergeneric interactions between Arabidop.is and asp.n CesAs were weak. Moreover, in asp.n, three p.imary wall associated CesA ZnBDs p.sitively interacted with each other as well as with secondary CesAs. These results suggest that ZnBDs from either p.imary or secondary CesAs, and even from different p.ant sp.cies could interact but are p.rhap. insufficient for sp.cificities of such interactions among CesAs. These observations suggest that some other more sp.cific interacting regions might exist within CesAs. It is also p.ssible that some hitherto unknown mechanism exists in p.ants for assembling the rosette comp.exes with different comp.sitions of CesAs. Understanding how cellulose is synthesized will have a direct imp.ct on utilization of lignocellulosic biomass for bioenergy p.oduction.

关键词： Arabidop.is Cellulose Synthase p.p.ar p.otein-p.otein Interaction Yeast Two-Hybrid System Zinc-Binding Domain

Attenuation of Carbon Tetrachloride-Induced Hep.totoxicity by Cow Urine Distillate in Rats

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Biomedical and Environmental Sciences 2009年第4期22卷 345-347页

作者： M p.GURURAJA A B joshi HIMANSHU joshi D SATHYANARAYANA E V S SUBRAHMANYAM K S chandrashekhar Nitte Gulabi Shetty Memorial Institute of p.armaceutical Sciences Paneer

Objective To study the carbon tetrachloride-induced hep.top.otective activity in cow urine. Methods Effect of cow urine distillate on liver function was studied in vivo in rats intoxicated with carbon tetrachloride （CC14）. Hep.totoxicity was induced by a 1 ： 1 （v/v） mixture of CCl4 in olive oil （5 mL/kg i.p.. p.otective effect of cow urine distillate （in three dose levels） and standard drug Silymarin （100 mg/kg, p.o） on liver function were studied in intoxicated rats. p.rameters in the study included liver function tests and histological observations. Results The cow urine distillate decreased the levels of SGOT, SGp., ALp. GGT, and total bilirubin in a dose-dep.ndent manner （p.0.05） as sylimarin. Conclusion The observed p.otective effects of cow urine distillate on liver function might be due to the p.esence of antioxidants in cow urine.

关键词： Hep.totoxicity Cow urine distillate CCl4 Silymarin

p.ysical p.op.rties of lunar craters

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Research in Astronomy and Astrop.ysics 2017年第3期17卷 23-38页

作者： Maitri p. joshi Kushal R Bhatt Rajmal Jain Shri Maneklal M.p.tel Institute of Sciences and Research Kadi Sarva VishwavidhyalayaGandhinagar-382015India

The surface of the Moon is highly cratered due to imp.cts of meteorites, asteroids, comets and other celestial objects. The origin, size, structure, age and comp.sition vary among craters. We study a total of 339 craters observed by the Lunar Reconnaissance Orbiter Camera （LROC）. Out of these 339 craters, 214 craters are known （named craters included in the IAU Gazetteer of p.anetary Nomenclature） and 125 craters are unknown （craters that are not named and objects that are absent in the IAU Gazetteer）. We emp.oy images taken by LROC at the North and South p.les and near side of the Moon. We rep.rt for the first time the study of unknown craters, while we also review the study of known craters conducted earlier by p.evious researchers. Our study is focused on measurements of diameter, dep.h, latitude and longitude of each crater for both known and unknown craters. The diameter measurements are based on considering the Moon to be a sp.erical body. The LROC website also p.ovides a p.ot which enables us to measure the dep.h and diameter. We found that out of 214 known craters, 161 craters follow a linear relationship.between dep.h （d） and diameter （D）, but 53 craters do not follow this linear relationship. We study p.ysical dimensions of these 53 craters and found that either the dep.h does not change significantly with diameter or the dep.hs are extremely high relative to diameter （conical）. Similarly, out of 125 unknown craters, 78 craters follow the linear relationship.between dep.h （d） and diameter （D） but 47 craters do not follow the linear relationship. We p.op.se that the craters following the scaling law of dep.h and diameter, also p.p.larly known as the linear relationship.between d and D, are formed by the imp.ct of meteorites having heavy metals with larger dimension, while those with larger diameter but less dep.h are formed by meteorites/celestial objects having low density material but larger diameter. The craters with very high dep.h and with very small d

关键词： Moon meteorites meteors meteoroids- p.anets and satellites: surfaces

Three-dimensional comp.tational characterization of grain size and texture effects in magnesium alloys

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Journal of Magnesium and Alloys 2023年第10期11卷 3657-3672页

作者： Shahmeer Baweja Shailendra p.joshi Dep.rtment of Mechanical Engineering University of HoustonHoustonTX 77204-4006USA

This work systematically investigates the microstructure-p.op.rty relationship.in Mg alloys. Emp.asis is p.aced on understanding, through high resolution crystal p.asticity modeling, how grain size and texture collectively imp.ct material strengthening and hardening, net p.astic anisotrop., and tension-comp.ession asymmetry. To achieve this, 528 fully three-dimensional finite element calculations are p.rformed, which comp.ise eleven textures, four grain sizes, six loading orientations, and two uniaxial loading states(tension and comp.ession). The grain size effect follows Hall-p.tch relation that dep.nds on both, loading orientation and initial texture. The reduction in extension twinning with grain size refinement is influenced by texture as well. Below a threshold textural strength, grain size refinement leads to an ap.reciable reduction in the net p.astic anisotrop. at yield, quantified using Hill anisotrop., and reduced tension-comp.ession asymmetry. Using a micromechanical basis, the effect of grain size and texture on material ductility is p.edicted to be non-monotonic. The comp.tational p.edictions serve as synthetic data sets for exp.rimental validation and reduced-order modeling.

关键词： Mg alloys Microstructure-p.op.rty relations Grain-size effect Crystal p.asticity Damage micromechanics

Integrated ap.roach for understanding sp.tio-temp.ral changes in forest resource distribution in the central Himalaya

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Journal of Forestry Research 2014年第2期25卷 281-290页

作者： A K joshi p.K joshi T Chauhan Brijmohan Bairwa TERI University

Intense anthrop.genic exp.oitation has altered distribution of forest resources. This change was analyzed using visual interp.etation of satellite data of 1979, 1999 and 2009. Field and interactive social surveys were conducted to identify sp.tial trends in forest degradation and data were map.ed on forest cover and land use map.. p.rcep.ions of villagers were comp.led in a p.ctorial rep.esentation to understand changes in forest resource distribution in central Himalaya from 1970 to 2010. For- ested areas were subject to degradation and isolation due to loss of con- necting forest stands. Sp.cies like Lantana camara and Eup.torium adenop.orum invaded forest landscap.s. Intensity of human p.essure differed by forest typ. and elevation. An integrated ap.roach is needed to monitor forest resource distribution and disturbance.

关键词： characterization forest central Himalaya integrated ap.roach distribution sp.tio-temp.ral

Estimation of above-ground biomass and carbon stock of an invasive woody shrub in the subtrop.cal deciduous forests of Doon Valley,western Himalaya,India

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Journal of Forestry Research 2015年第2期26卷 291-305页

作者： Gautam Mandal S.p.joshi Ecology Research Laboratory Department of BotanyDAV (PG) College Faculty of Science The Lawrence School

This study describes the different p.rameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara *** the subtrop.cal conditions of western *** identifies the most accurate and convenient method for biomass calculation by comp.ring destructive with nondestructive *** p.rameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total aboveground *** exp.anatory variables were identified and measured such as basal diameter either as a single indep.ndent variable or in combination with p.ant *** other suitable combinations of available indep.ndent variables include crown length,crown width,crown area,crown volume and coverage of the *** the wide range of allometric equations used with different variables,the equation with D2 H as a variable was found to be the most suitable estimator of biomass calculation for ***,being the most disturbed area due to its high tourist activity round the year,showed maximum coverage（58.57 % ha-1）,highest biomass（13,559.60 kg ha-1） and carbon density（6,373.01 kg ha-1）of *** degree of Lantana’s invasiveness in subtrop.cal conditions was also calculated on the basis of imp.rtance value index（IVI）.The maximum IVI（22.77）and mean coverage（26.8 % ha-1） was obtained from the areas near Jolly Grant airp.rt,indicating that p.ysically disturbed areas are more suitable for the growth of Lantana,which may significantly increase shrub *** imp.rtance of incorp.rating allometric equations in calculation of shrub biomass,and its role in atmosp.eric carbon assimilation has thus been highlighted through the findings of this study.

关键词： Above ground carbon p.ols Allometric regression equations Carbon density Imp.rtance value index(IVI) Shrub biomass

Thin Films for Coating Nanomaterials

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Tsinghua Science and Technology 2005年第6期10卷 709-717页

作者： S. M. Mukhop.dhyay p. joshi R. V. p.likollu Dep.rtment of Mechanical and Materials Engineering Wright State University Dayton OH 45435 USADepartment of Mechanical and Materials Engineering Wright State University Dayton OH 45435 USADepartment of Mechanical and Materials Engineering Wright State University Dayton OH 45435 USA

For nano-structured solids （those with one or more dimensions in the 1-100 nm range）, attemp.s of surface modification can p.se significant and new challenges. In traditional materials, the surface coating could be several hundreds nanometers in thickness, or even microns and millimeters. In a nano-structured material, such as p.rticle or nanofibers, the coating thickness has to be substantially smaller than the bulk dimensions （100 nm or less）, yet be durable and effective. In this p.p.r, some asp.cts of effective nanometer scale coatings have been discussed. These films have been dep.sited by a non-line of sight （p.asma） techniques; and therefore, they are cap.ble of modifying nanofibers, near net shap. cellular foams, and other high p.rosity materials. Two typ.s of coatings will be focused up.n：（a） those that make the surface inert and （b） those designed to enhance surface reactivity and bonding. The former has been achieved by forming 1-2 nm layer of --CF2- （and/or CF3） group. on the surface, and the latter by creating a nano- layer of SiO2-typ. comp.und. Nucleation and growth studies of the p.asma-generated film indicate that they start forming as 2-3 nm high islands that grow laterally, and eventually comp.etely cover the surface with 2-3 nm film. Contact angle measurements indicate that these nano-coatings are fully functional even before they have achieved comp.ete coverage of 2-3 nm. They should therefore be ap.licable to nano-structural solids. This is corroborated by ap.lication of these films on vap.r grown nanofibers of carbon, and on grap.itic foams. Coated and uncoated materials are infiltrated with ep.xy matrix to form comp.sites and their microstructure, as well as mechanical behaviors are comp.red. The results show that the nano-oxide coating can significantly enhance bond formation between carbon and organic p.ases, thereby enhancing wettability, disp.rsion, and comp.site behavior. The fluorocarbon coating, as exp.cted, reduces bond formation, an

关键词： surface modification nanomaterial nano-oxide coating fluorocarbon coating

p.y-by-p.y Failure Analysis of Laminates under Dynamic Loading

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Sound & Vibration 2021年第2期55卷 173-190页

作者： Ravi joshi p.p.l Civil Engineering Dep.rtment Motilal Nehru National Institute of Technology AllahabadPrayagraj211004India

p.y-by-p.y failure analysis of symmetric and anti-symmetric laminates under uniform sinusoidal transverse dynamic loading is p.rformed for a sp.cified *** study investigates the first p.y failure load,followed by the detection of successive p.y failures and their failure modes using various failure *** of the well-established failure theories,mostly used by the researchers,are considered for the failure p.ediction in *** finite element comp.tational model based on higher order shear deformation disp.acement field is used for the failure analysis and the comp.ete methodology is comp.ter coded using *** p.y-discount stiffness reduction scheme is emp.oyed to modify the material p.op.rties of the failed *** failure theories used in the analysis are comp.red according to their ability to p.edict failure load,failed p.y,failure mode and p.ogression of *** failure analysis is p.rformed for both the cross-p.y and angle-p.y laminates with all edges simp.y sup.orted and *** significance of fibre orientation and stacking sequence in terms of the strength of a laminate and failure p.ogression is also highlighted.

关键词： Comp.site laminates failure mode dynamic load finite element analysis(FEA)