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Hunting of hunted:an ensemble modeling approach to evaluate suitable habitats for caracals in India

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Ecological Processes 2022年第1期11卷 744-757页

作者： Ashish Kumar Jangid chandra Prakash Singh Jai Singh Parihar Jasbir Singh Chauhan Rajnish Kumar Singh Prakash Kumar Verma Amritanshu Singh Shantanu sharma shekhar Kolipaka Wildlife Institute of India DehradunUttarakhand 248001India Space Applications Centre Indian Space Research OrganisationAhmedabadGujarat 380015India Madhya Pradesh State Forest Department Madhya Pradesh Tiger Foundation SocietyKuno National ParkBhopalMadhya Pradesh 462001India Leo Foundation WageningenThe Netherlands

Background:Large-scale hunting and various anthropogenic pressures in the recent past have pushed the Asiatic caracal(Caracal caracal schmitzi),an elusive medium-sized and locally threatened felid species towards local extinction in *** widely distributed historically,it has been sparsely reported from several regions of central and northern states in India till twentieth ***,the species distribution became confined only to the states of Rajasthan,Gujarat and Madhya Pradesh,which have had reported sightings in the twenty-first *** order to highlight the potentially suitable habitats for Asiatic caracals in India,we targeted forth-filtering of the spatial model ensemble by creating and utilizing the validated and spatially thinned species presence information(n=69)and related ecological variables(aridity,NDVI,precipitation seasonality,temperature seasonality,terrain ruggedness),filtered with anthropological variable(nightlight).Results:Out of eight spatial prediction models,the two most parsimonious models,Random Forest(AUC 0.91)and MaxEnt(AUC 0.89)were weighted and *** ensemble model indicated several clustered habitats,covering 1207.83 km^(2)areas in Kachchh(Gujarat),Aravalli mountains(Rajasthan),Malwa plateau(Rajasthan and Madhya Pradesh),and Bundelkhand region(Madhya Pradesh)as potentially suitable habitats for *** probabilities of pixels were further regressed with converted vegetation height data within selected highly potential habitats,i.e.,Ranthambore Kuno Landscape(RKL)(suitability~0.44+0.03(vegetation height)^(**),R^(2)=0.27).The regression model inferred a significant positive relation between vegetation height and habitat suitability,hence the lowest ordinal class out of three classes of converted vegetation height was masked out from the RKL,which yielded in an area of 567 km^(2) as potentially highly suitable habitats for caracals,which can be further proposed as survey areas and conservation priority are

关键词： Medium-sized cat Caracal caracal schmitzi Potentially suitable habitat Drylands Potential survey area

Gender plasticity uncovers multiple sexual morphs in natural populations of Cedrus deodara (Roxb.) G. Don

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Ecological Processes 2021年第1期10卷 459-469页

作者： Vinod Prasad Khanduri Arun Sukumaran chandra Mohan sharma Department of Forestry College of ForestryVCSG Uttarakhand University of Horticulture and ForestryRanichauriTehri GarhwalUttarakhand 249199India Present Address:State Farming Corporation of Kerala Chithalvetty EstateKalanjoor KollamKeralaIndia.

Background:The expression of gender in gymnosperms is challenging because the extent of variability in gender segregations in tree crowns and selection pressure of nature can modify the gender through ***:An in-depth investigation on spatial segregation of genders in tree crowns and sex expression of a total of 500 trees in five different natural populations of Cedrus deodara was carried out and verified the occurrence of subdioecious(co-existence of male,female,and monoecious)genders in ***:Five different sexual morphs were apparent among the 500 selected individuals as(1)pure male(M):bearing only male strobili in the whole crown with 22.2%;(2)pure female(F):bearing only female strobili in the whole crown with 12.4%;(3)mixed-monoecious(MM):bearing both male and female strobili with 13.6%;(4)predominantly female(PF)with 25.6%;and(5)predominantly male(PM)with 26.2%.The occurrence of multiple sexual morphs resulted from the complex selection pressure,which increased the stability of the *** segregation of genders in crown layers deemed to increase the fitness that may be a mechanism for accelerating *** results of the study suggest that the subdioecious gender expression in *** is evolved through the monoecy–paradioecy *** production of male strobili revealed non-significant effect of tree sizes whereas a significant effect was observed for the production of female *** study established that the total pollen and seed outputs in *** changed frequently according to gender ***:The size of the tree,resource availability,sex allocation,plant architecture,gender segregation in crowns,and habitat conditions are the prominent causes for gender plasticity.

关键词： Gender Sex expression Gender segregation Strobili Pre-fertilisation Monoecy Dioecy

Pollinator-mediated self-pollination and reproductive assurance in an isolated tree of Magnolia grandiflora L.

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Ecological Processes 2020年第1期9卷 517-525页

作者： Arun Sukumaran Vinod Prasad Khanduri chandra Mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and ForestryRanichauriTehri GarhwalUttarakhand 249199India

Background:The ability to produce seeds when pollinators or potential mates are scarce is one of the principal advantages of self-pollination in flowering ***,the role of pollinators mediating self-pollination to ensure seed set when pollen or potential mates are limited has received less *** study examined the reproductive consequences and involvement of pollinators in assuring seed set in an isolated tree of Magnolia grandiflora,a predominantly outcrossing ***:We tested various aspects of reproduction such as flower density,floral rewards,stigma receptivity,pollinator abundance and behaviour,fruit set and seed set,in two successive reproductive years(2015-2016).Results:Flowers of *** possess a suite of traits facilitating pollinator-mediated self-pollination(PMS),although the chances of autonomous self-pollination are reduced due to herkogamy,spatial separation of anther and *** mean pollen production/flower was 5,152,289±285,094 with a pollen-to-ovule ratio of 39430±*** found a significant positive correlation between number of visits and seed production for bees(r=0.5099,p=0.0007)and beetles(r=0.7159,p=0.00001),indicating these are effective at *** was a significant negative correlation for thrips(r=-0.3206,p=0.044)and no correlation for flies or *** percent fruit set was 100%and the seed set per ovule ranged between 19 and 20%.Conclusions:PMS will guarantee reproductive assurance and mitigate the effect of reduced mates or pollen limitation which is expected to increase the fecundity and establishment of individual trees in geographically isolated locations.

关键词： Pollinator-mediated self-pollination Magnolia grandiflora Autonomous self-pollination Pollinator behaviour Reproductive assurance

THE EFFECT OF MAGNETIC FIELDS ON LOW FREQUENCY OSCILLATING NATURAL CONVECTION WITH PRESSURE GRADIENT

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Applied Mathematics and Mechanics(English Edition) 2003年第3期24卷 274-283页

作者： G.C.sharma Madhu Jain Mahesh chandra School of Mathematical Sciences Institute of Basic ScienceSchool of Mathematical SciencesInstitute of Basic ScienceSchool of Mathematical SciencesInstitute of Basic Science KhandariAgra-282002IndiaKhandariAgra-282002IndiaKhandariAgra-282002India

The oscillating natural convection in the presence of transverse magnetic field with time depending pressure gradient is studied. The analysis of the problem is carried out by assuming that the fluid is flowing in a parallel plate configuration. The emphasis is on low frequency oscillating convective flows induced by g-jitter associated with micro gravity because of their importance to the space processing materials. A general solution for an oscillating flow in the presence of transverse magnetic field is carried out. Some special cases of the oscillating flow and its response to an applied magnetic field are performed. It was observed that the behavior of oscillating free convective flows depends on frequency, amplitude of the driving buoyancy forces, temperature gradient,magnetic field and the electric conditions of the channel walls. In the absence of magnetic field, buoyancy force plays a predominant role in driving the oscillatory flow pattern, and velocity magnitude is also affected by temperature gradients. To suppress the oscillating flow external magnetic field can be used. It is also found that the reduction of the velocity is inversely proportional to the square of the applied magnetic field with conducting wall but directly proportional to the inverse of the magnetic field with insulating wall. Detailed calculations and computational results are also carried out to depict the real situation.

关键词： convection g- jitter acceleration buoyancy force magnetic field pressure gradient

Reproductive biology of Cornus capitata Wall. ex Roxb.: a native species in East Asia

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Journal of Forestry Research 2019年第6期30卷 2039-2050页

作者： Vinod Prasad Khanduri Arun Sukumaran chandra Mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and Forestry

The reproductive biology of Cornus capitata was studied in detail from June 2014 to October 2015 in Tehri Garhwal, Uttarakhand, western Himalaya, India and elucidated floral morphology, confirming autogamy, geitonogamy, and xenogamy. A new inflorescence ball formed each year with developing fruits that were initiated the previous year; thus reproduction is a continuous cycle. The total pollen production within a tree ranged between 4.0 × 10~7 and 9.3 × 10~7. Anthesis peaked between 08:00 and 10:00. There was significant effect of micro-environmental condition on anthesis(F = 243.8, p = 3.01). A significant positive relationship between the number of lateral shoots and total inflorescence showed that the inflorescence production in C. capitate depends largely on the number of lateral shoots. Time and concentration of various solutions significantly affected pollen germination(time: F = 5.39, p = 0.002; concentration: F = 1.40,p = 0.234). Anthophora bees and thrips were observed as the main pollinators. There was a significant difference in seed set between natural and obligate self-pollination(t = 11.84, p = 1.99). Significant effect was also observed on fruit size(t = 8.88, p = 2.09) between open and shaded conditions. SEM micrographs of pollen grains showed that the shape of dehydrated pollen grains differed greatly due to variations in the rate of dehydration among pollen grains within the anther. Seed germination was observed only in quality seed derived from open pollination, supporting xenogamy in C. capitata. Findings of the present study will be of immense value in formulating effective conservation measures for the species in wild habitats.

关键词： Floral development Pollen production Pollination Pollinators Reproductive success SEM analysis

Improvement of phosphorus uptake,phosphorus use efficiency,and grain yield of upland rice(Oryza sativa L.)in response to phosphate-solubilizing bacteria blended with phosphorus fertilizer

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Pedosphere 2022年第5期32卷 752-763页

作者： Pratibha RAWAT Anita sharma Deepti SHANKHDHAR Shailesh chandra SHANKHDHAR Department of Plant Physiology College of Basic Sciences&HumanitiesGovind Ballabh Pant University of Agriculture&TechnologyPantnagar-263145(India) Department of Microbiology College of Basic Sciences&HumanitiesGovind Ballabh Pant University of Agriculture&TechnologyPantnagar-263145(India)

Phosphorus(P)limitation in soil is a major concern for crop ***,the use of chemical fertilizer is hazardous to the environment and ***,the use of phosphate-solubilizing bacteria(PSB)is an eco-friendly approach for a sustainable agricultural *** the present study,a field trial was conducted for two consecutive years to study the effects of three PSB strains isolated,Bacillus licheniformis,Pantoea dispersa,and Staphylococcus sp.,with different P fertilizer rates on P uptake,P use efficiency(PUE),and grain yield of *** activities of soil enzymes were also studied in relation to PSB *** analysis of the yield and biochemical parameters revealed that inoculation of PSB consortium could reduce almost 50%of the recommended P dose in rice *** PSB strains in combination with 50%P dose was most effective and showed the highest increases in P uptake and PUE as compared to the uninoculated ***,the PSB consortium combined with 50%P dose contributed to 50.58%and35.64%yield increases compared to the uninoculated control for 2018 and 2019,*** increases in the activities of soil dehydrogenase,alkaline phosphatase,and acid phosphatase were also recorded under PSB treatment.

关键词： bacterial inoculation enzyme activity phosphate solubilization index recommended P dose soil dehydrogenase soil phosphatase

Numerical investigation of the effect of transitory strand opening on mixing in a multistrand tundish

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 535-542页

作者： Sabin Kumar Mishra Pradeep Kumar Jha Satish chandra sharma Satish Kumar Ajmani Department of Mechanical and Industrial Engineering Indian Institute of Technology RoorkeeRoorkee 247667UttarakhandIndia Steelmaking and Casting Research Group Tata SteelR&DBurma MinesJamshedpur 831007JharkhandIndia

In a multistrand,the outlet near the inlet produces short circuiting *** leads to the formation of dead zones inside the tundish,and consequently,the mean residence time *** the present study,numerical investigation of mixing inside a delta shaped tundish with sloping boundaries was carried out by solving the Navier-Stokes equation and employing the standard turbulence *** decrease the dead zone volume inside the tundish,the effect of closing the outlet near the inlet for a small amount of time and further opening it on the mixing behavior of the tundish was *** outlets near the inlet were closed for varying amount of time,and the transient analysis of fluid flow and the tracer dispersion study were carried out to find the mixing parameters of the tundish,namely,mean residence time and the ratio of mixed to dead volume of the *** optimum closure time of the near outlet has been found,which yields best mixing inside the *** numerical code was validated against the experimental observation by performing the tracer dispersion study inside a multistrand tundish and the reasonably good match between the experimental and numerical results in terms of residence time distribution （RTD） *** results obtained from the present study confirm the strong role of choosing the right time for opening and closing the outlets to get improved characteristics for the fluid flow and mixing behavior of the *** educational version of computational fluid dynamics （CFD） software PHOENICS was used to solve the governing equations and interpret the results in different forms.

关键词： continuous casting billets tundish flow simulation mean residence time dead volume computational fluid dynamics (CFD)

Green synthesis of biocompatible gold nanoparticles using Fagopyrum esculentum leaf extract

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Frontiers of Materials Science 2011年第4期5卷 379-387页

作者： Punuri Jayasekhar BABU Pragya sharma Mohan chandra KALITA Utpal BORA Biotech Hub Centre for the Environment Indian Institute of Technology Guwahati Guwahati Assam-781039 India Biomaterials and Tissue Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati Assam-781039 India Department of Biotechnology Gauhati University Guwahati Assam-781039 India

This report describes the use of ethnolic extract of Fagopyrum esculentum leaves for the synthesis of gold nanoparticles. UV-visible spectroscopy analysis indicated the successful formation of gold nanoparticles. The synthesized nanoparticles were characterized by transmission electron microscopy （TEM）, high resolution TEM （HRTEM） and were found to be spherical, hexagonal and triangular in shape with an average size of 8.3 nm. The crystalline nature of the gold nanoparticles was confirmed from *** diffraction （XRD） and selected-area electron diffraction （SAED） patterns. Fourier transform infrared （FT-IR） and *** X-ray analysis （EDX） suggested the presence of organic biomolecules on the surface of the gold nanoparticles. Cytotoxicity tests against human HeLa, MCF-7 and IMR-32 cancer cell lines revealed that the gold nanoparticles were non-toxic and thus have potential for use in various biomedical applications.

关键词： biomaterials crystal growth electron microscopy Fourier transforminfrared spectroscopy adsorption

Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil Manna Deepa Devapal Sharad chandra sharma Jyotsna Dutta Majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT Mesra RanchiJharkhandIndia Department of Metallurgical and Materials Engineering IIT KharagpurWest BengalIndia Vikram Sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron Microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of Hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured Hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(Hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： Mechanical milling Microstructure Process control agent(PCA) CoNiCrAlY Toluene Stearic acid Flowability