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Cryptic species composition and genetic diversity within Bemisia tabaci complex in soybean in India revealed by mtCOI DNA sequence

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Journal of Integrative Agriculture 2015年第9期14卷 1786-1795页

作者： Prasanna H C kanakala S Archana k Jyothsna P varma r k Malathi V G Division of Vegetable Improvement Indian Institute of Vegetable Research Advanced Centre for Plant Virology Division of Plant PathologyIndian Agricultural Research Institute Department of Plant Pathology Jawaharlal Nehru Krishi Vishwavidyalaya

Bemisia tabaci is a cryptic species complex, causing signiifcant loss on many agricultural y important crops worldwide. knowledge on species composition and diversity within B. tabaci complex is critical for evolving sustainable pest management strategies. Here we investigate the whitelfy species complex in soybean in major soybean growing states of India. The mitochondrial cytochrome oxidase gene subunit-1 (mtCOI) based phylogenetic relationships established using Bayesian methods indicated the existence of three cryptic species namely Asia I, Asia II 1, and Asia II 7. Al the haplotypes detected in the study could be assigned to these three cryptic species fol owing the species demarcation criteria of 3.5%divergence threshold. Of these, Asia II 1 was found to be predominant with wide spread distribution across the surveyed regions from cool temperate zones to hot and humid tropical plains. On the contrary, cryptic species Asia II 7 showed localized distribu-tion. The Asia II 1 exhibited the highest haplotype diversity and Asia I showed high level of nucleotide diversity. There was a signiifcantly high genetic differentiation among these three cryptic species. The MEAM 1, a dreadful invasive species was not detected in the specimens tested in the current study. The diversity and distribution of three cryptic species is discussed in the light of current knowledge on distribution of whitelfy species in India and yel ow mosaic disease observed during sampling survey.

关键词： whitefly mitochondrial cytochrome oxidase gene subunit-1 AsiaⅠ AsiaⅡ 1 AsiaⅡ 7 begomovirus and yellow mosaic disease

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Nano/Micro-Structural Supramolecular Biopolymers: Innovative Networks with the Boundless Potential in Sustainable Agriculture

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Nano-Micro Letters 2024年第8期16卷 79-101页

作者： roohallah Saberi riseh Mohadeseh Hassanisaadi Masoumeh Vatankhah rajender S.varma Vijay kumar Thakur Department of Plant Protection Faculty of AgricultureVali-e-Asr University of RafsanjanImam Khomeini SquareRafsanjan ***Iran Centre of Excellence for research in Sustainable Chemistry Department of ChemistryFederal University of São CarlosSão CarlosSP 13565‑905Brazil Biorefining and Advanced Materials research Center Scotland’s Rural Collage(SRUC)Edinburgh EH93JGUK

Sustainable agriculture plays a crucial role in meeting the growing global demand for food while minimizing adverse environmental impacts from the overuse of synthetic pesticides and conventional *** this context,renewable biopolymers being more sustainable offer a viable solution to improve agricultural sustainability and ***/micro-structural supramolecular biopolymers are among these innovative biopolymers that are much sought after for their unique *** biomaterials have complex hierarchical structures,great stability,adjustable mechanical strength,stimuli-responsiveness,and self-healing *** molecules may be added to their flexible structure,for enabling novel agricultural *** overview scrutinizes how nano/micro-structural supramolecular biopolymers may radically alter farming practices and solve lingering problems in agricultural sector namely improve agricultural production,soil health,and resource *** bioactive ingredient released from biopolymers allows the tailored administration of agrochemicals,bioactive agents,and biostimulators as they enhance nutrient absorption,moisture retention,and root ***/micro-structural supramolecular biopolymers may protect crops by appending antimicrobials and biosensing entities while their eco-friendliness supports sustainable *** their potential,further studies are warranted to understand and optimize their usage in agricultural *** effort seeks to bridge the knowledge gap by investigating their applications,challenges,and future prospects in the agricultural *** experimental investigations and theoretical modeling,this overview aims to provide valuable insights into the practical implementation and optimization of supramolecular biopolymers in sustainable agriculture,ultimately contributing to the development of innovative and eco-friendly solutions to enhance agricultural productivity while minimizing envir

关键词： Supramolecular Biopolymers Sustainable agriculture Nanotechnology

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Effect of nano-and micron-sized k0.5Na0.5NbO3 fillers on the dielectric and piezoelectric properties of PVDF composites

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Journal of Advanced Ceramics 2016年第4期5卷 92-页

作者： Bharathi PONrAJ rajasekhar BHIMIrEDDI k.B.r.varma Materials research Centre Indian Institute of Science Bangalore-560012 India

Polymer nanocrystal composites were fabricated by embedding polyvinylidene fluoride (PVDF) with k0.5Na0.5NbO3 (kNN) nanocrystallites of different volume fraction using the hot-pressing technique. For comparison, PVDF–kNN microcrystal composites of the same compositions were also fabricated which facilitated the studies of the crystallite size (wide range) effect on the dielectric and piezoelectric properties. The structural, morphological, dielectric, and piezoelectric properties of these nano and micro crystal composites were investigated. The incorporation of kNN fillers in PVDF at both nanometer and micron scales above 10 vol% resulted in the formation of polar β-form of PVDF. The room temperature dielectric constant as high as 3273 at 100 Hz was obtained for the PVDF comprising 40 vol% kNN nanocrystallites due to dipole–dipole interactions (as the presence of β-PVDF is prominent), whereas it was only 236 for the PVDF containing the same amount (40 vol%) of micron-sized crystallites of kNN at the same frequency. Various theoretical models were employed to predict the dielectric constants of the PVDF–kNN nano and micro crystal composites. The PVDF comprising 70 vol% micron-sized crystallites of kNN exhibited a d33 value of 35 pC/N, while the nanocrystal composites of PVDF–kNN did not exhibit any piezoelectric response perhaps due to the unrelieved internal stress within each grain, besides the fact that they have less domain walls.

关键词： polyvinylidene fluoride (PVDF) k 0.5 Na 0.5 NbO 3 (kNN) composites β -PVDF nanocrystallites

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Spectral narratives of microstructural restyling and their controls on hydrocarbon generation potential from coal

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International Journal of Coal Science & Technology 2023年第3期10卷 167-189页

作者： Tushar Adsul Santanu Ghosh Anwita Ojha Sudip Bhattacharyya Atul kumar varma Coal Geology and Organic Petrology Laboratory Department of Applied GeologyIndian Institute of Technology(Indian School of Mines)DhanbadJharkhand 826004India Department of Geology Mizoram UniversityAizawlMizoram 796004India Specialized Coal Petrography Laboratory Natural Energy ResourcesMission II-BGeological Survey of IndiaDK-6Sector-IlSalt Lake CityKolkataWest Bengal 700091India

The low to medium-rank Tertiary coals from Meghalaya,India,are explored for the first time for their comprehensive micro-structural characterization using the FTIr and raman ***,results from these coals are compared with the Permian medium and high-rank coals to understand the microstructural restyling during coalification and its controls on hydrocarbon *** coal samples are grouped based on the mean random vitrinite reflectance values to record the transformations in spectral attributes with increasing coal *** aliphatic carbon and the apparent aromaticity respond sharply to the first coalification jump(r:0.50%)during low to medium-rank transition and anchizonal metamorphism of the high-rank ***,the raman band intensity ratio changes during the first coalification jump but remains invari-able in the medium-rank coals and turns subtle again during the onset of pregraphitization in high-rank coals,revealing a polynomial trend with the coal *** rock-Eval hydrogen index and genetic potential also decline sharply at the first coalification ***,an attempt to comprehend the coal microstructural controls on the hydrocarbon poten-tial reveals that the Tertiary coals comprise highly reactive aliphatic functionalities in the type I-S kerogen,along with the low paleotemperature(74.59-112.28℃)may signify their potential to generate early-mature ***,the presence of type II-II admixed kerogen,a lesser abundance of reactive moieties,and overall moderate paleotemperature(91.93-142.52℃)of the Permian medium-rank coals may imply their mixed hydrocarbon ***,anchizonal metamorphism,polycondensed aromatic microstructure,and high values of paleotemperature(~334.25 to~366.79℃)of the high-rank coals indicate a negligible potential of producing any hydrocarbons.

关键词： Early mature oil generation Meghalaya high-sulfur coal Type II-S kerogen Microstructural ordering Coalification jump Hydrocarbon generation potential

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Water and nutrient recovery from urine:A lead up trail using nano-structured In_(2)S_(3)photo electrodes

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Chinese Physics B 2021年第5期30卷 531-535页

作者： r Jayakrishnan T r Sreerev Adith varma Department of Physics University of KeralaThiruvananthapuramKerala 695581India Photovoltaic research Laboratory Christian College Chenagnnur 689122India

Developments of economic systems are critical for bio-regenerative life support systems in manned space *** this work we report on the feasibility of using two direct sunlight powered processes sequentially for the recovery of water and nutrients from *** work presents experimental evidence on nutrient and water recovery achieved using the proto-type designed and *** report the design and testing of a solar still which would serve on the nutrient recovery *** cooled condensate from the solar still is fed into a solar powered electrolysis unit where nano-structured indium sulphide(In_(2)S_(3))thin films coated over fluorine doped tin oxide(SnO_(2):F)substrate serve as one of the working *** electrolysis takes place in the absence of an electrolyte which manifests as a technical achievement of our *** results show that the COD level in the recycled water is very *** In_(2)S_(3)photo-electrodes are stable without any physical damage after the process.

关键词： semiconductors water quality thin film structure and morphology electrolysis

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C4二醇的发酵生产及其化学催化升级为高价值化学品的研究进展

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Chinese Journal of Catalysis 2023年第9期52卷 99-126页

作者： Abhishek r.varma Bhushan S.Shrirame Sunil k.Maity Deepti Agrawal Naglis Malys Leonardo rios-Solis Gopalakrishnan kumar Vinod kumar 印度海得拉巴理工学院化学工程系特伦甘纳桑加雷迪印度 CSIr-印度石油研究所材料资源效率处生物化学和生物技术区北阿坎德邦德拉敦印度考纳斯理工大学化学技术学院有机化学系考纳斯立陶宛伦敦大学学院生物化学工程系伦敦英国延世大学土木与环境工程学院首尔韩国克兰菲尔德大学水能源与环境学院克兰菲尔德英国印度鲁尔基理工学院生物科学与生物工程系北阿坎德邦印度碳源可再生能源有限公司爱丁堡英国

化石资源的过度消耗导致能源和环境污染问题,迫切需要科研人员开发出可持续、低能耗、绿色低碳的化学品生产技术.生物技术利用“细胞工厂”,以生物质等可再生资料为原料生产基础化学品,是以化石资源为原料的合成方法的潜在替代方案.然而... 详细信息

化石资源的过度消耗导致能源和环境污染问题,迫切需要科研人员开发出可持续、低能耗、绿色低碳的化学品生产技术.生物技术利用“细胞工厂”,以生物质等可再生资料为原料生产基础化学品,是以化石资源为原料的合成方法的潜在替代方案.然而,利用生物技术生产全系列石化产品存在其自身的局限性,因此,人们对集成/混合方法越来越感兴趣,该方法先采用生物技术对生物质升级,再通过化学催化的途径使其转化为含有活性官能团的产物.本文主要综述了C4二醇的三种重要结构异构体,2,3-、1,3-和1,4-丁二醇的生物生产方法,目前这些异构体主要通过石化路线生产,全球市场需求不断增长.首先,从集成方法的原理出发,总结了上述二醇的生物法生产现状,包括底物、微生物、发酵技术和代谢/途径工程和发酵技术.然后,全面总结了C4二醇催化升级以生产系列产物的最新研究进展,讨论了催化剂中不同活性位点对催化活性、产物选择性和催化剂稳定性的影响.此外,给出了集成方法的具体实例,解决开发C4二醇生物生产工艺的相关挑战,强调通过直接催化转化方法对其升级所存在的困难.最后,对C4二醇的发酵生产及其化学催化升级为高价值化学品的相关研究进行总结,对未来发展进行展望,并指出将生物催化和化学催化方法相结合对于拓宽生物质升级转化产物范围具有重要作用.

关键词：丁二醇发酵代谢工程多相催化 1,3-丁二烯 3-丁烯-1-醇 3-丁烯-2-醇甲乙酮

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Effect of TeO_(2) addition on the dielectric properties of CaCu_(3)Ti_(4)O_(12) ceramics derived from the oxalate precursor route

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Journal of Advanced Dielectrics 2013年第4期3卷 26-33页

作者： P.Thomas k.B.r.varma Dielectric Materials Division Central Power Research Institute Bangalore 560080India Materials research Centre Indian Institute of Science Bangalore 560012India

CaCu_(3)Ti_(4)O_(12)(CCTO)ceramics which has perovskite structure gained considerable attention due to its giant *** it has high tan(0.1 at 1 kHz)at room temperature,which needs to be minimized to the level of practical ***,TeO_(2) which is a good glass former has been deliberately added to CCTO nanoceramic(derived from the oxalate precursor route)to explore the possibility of reducing the dielectric loss while maintaining the high *** structural,morphological and dielectric properties of the pure CCTO and TeO_(2) added ceramics were studied using X-ray diffraction,Scanning Electron Microscope along with Energy Dispersive X-ray Analysis(EDX),spectroscopy and Impedance *** the 2.0 wt.%TeO_(2) added ceramics,there is a remarkable difference in the microstructural features as compared to that of pure CCTO *** sample exhibited permittivity values as high as 7387 at 10 kHz and low dielectric loss value of 0.037 at 10 kHz,which can be exploited for the high frequency capacitors application.

关键词： Dielectric TeO_(2) CaCu_(3)Ti_(4)O_(12) ceramic

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STrUCTUrAL AND DIELECTrIC PrOPErTIES OF GLASSES IN THE SYSTEM TeO_(2)-CaCu_(3)Ti_(4)O_(12)

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Journal of Advanced Dielectrics 2012年第4期2卷 47-54页

作者： P.THOMAS k.B.r.varma Dielectric Materials Division Central Power research Institute Bangalore 560080India Materials research Centre Indian Institute of Science Bangalore 560012India

The glasses in the system(100-x)TeO_(2)-xCaCu_(3)Ti_(4)O_(12),(x=0.25 mol.%to 3 mol.%)were *** color varied from olive green to brown as the CaCu_(3)Ti_(4)O_(12)(CCTO)content increased in TeO_(2) *** X-ray powder diffraction and differential scanning calorimetric analyses that were carried out on the as-quenched samples confirmed their amorphous and glassy nature *** dielectric constant and loss in the 100Hz1MHz frequency range were monitored as a function of temperature(50-400℃).The dielectric constant(ε′_(τ))and the loss(D)increased as the CCTO content increased in TeO_(2) at all the frequencies and temperatures under ***,the ε′_(τ) and D were found to be frequency-independent in the 50-200℃ temperature *** value obtained for the loss at 1MHz was 0.0019 which was typical of low loss materials,and exhibited near constant loss(NCL)in the 100Hz-1MHz frequency *** electrical relaxation was rationalized using the electric modulus *** glasses may be of considerable interest as substrates for high frequency circuit elements in conventional semiconductor industries owing to their high thermal stability.

关键词： Dielectric TeO_(2) CaCu_(3)Ti_(4)O_(12) glass

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Polytene chromosomes of an Indian Himalayan black fly Simulium (Nevermannia) praelargum (Diptera:Simuliidae)

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Current Zoology 2010年第4期56卷 437-444页

作者： Willie HENrY Subrata kumar DEY rakesh varma Sachin THAPA William S PrOCUNIEr rG. Department of Zoology Darjeeling Government College Darjeeling West Bengal 734101 India School of Biotechnology West Bengal University of TechnologyBF-142 Sector 1Salt Lake City Kolkata 700064 West Bengal India Consultant North Bay Ontario P1B 5W6 Canada

High quality polytene chromosome maps (n=3) of a Himalayan Simuliid Simulium praelargum Datta, 1973 are presentedand represent the first cytological description of a taxon found in the feuerborni group, subgenus Nevermannia. Polytenechromosomes one (Ⅰ) and two (Ⅱ) are metacentric, chromosome three (Ⅲ) is submetacentric with the length of each chromosomeoccupying 37.25 %, 31.36 % and 31.34 % of the total complement length, respectively. Typical simuliid diagnostic intergenericchromosomal markers are found within the polytene complement of this species. The nucleolar organizer (N.O.) is found at thebase of the short arm of chromosome one (IS), the ring of Balbiani (r.B.), double bubble (D.B.) and triad occur in the short armof chromosome two (IIS), the Parabalbiani ring (P.B.) and grey band (gb) occur in the long arm of chromosome two (IIL) and theBlister (BL) and Capsule (Ca) occur in the short arm of chromosome three (HIS).Terminal bands at the end of HIS are heterochromatinizedand present atypically with respect to other simuliid fauna. Populations studied so far are unique among the Simuliidaein that they exhibit chromosome structural monomorphism. These high resolution polytene chromosome maps will form thebasis for future cytological characterization and phylogenetic comparisons amongst members of the feuerborni group.

关键词：多线染色体喜马拉雅双翅目染色体长度细胞学鉴定印度核仁组织者染色体结构

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On the mechanical aspect of additive manufactured polyether-ether-ketone scaffold for repair of large bone defects

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Biomaterials Translational 2022年第2期3卷 142-151页

作者： Seyed Ataollah Naghavi Changning Sun Mahbubeh Hejazi Maryam Tamaddon Jibao Zheng Leilei Wang Chenrui Zhang Swastina Nath varma Dichen Li Mehran Moazen Ling Wang Chaozong Liu Institute of Orthopaedic&Musculoskeletal Science University College LondonRoyal National Orthopaedic HospitalLondonUK State key Laboratory for Manufacturing Systems Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Mechanical Engineering University College LondonLondonUK.

Polyether-ether-ketone(PEEk)is widely used in producing prosthesis and have gained great attention for repair of large bone defect in recent years with the development of additive *** is due to its excellent biocompatibility,good heat and chemical stability and similar mechanical properties which mimics natural *** this study,three replicates of rectilinear scaffolds were designed for compression,tension,three-point bending and torsion test with unit cell size of 0.8 mm,a pore size of 0.4 mm,strut thickness of 0.4 mm and nominal porosity of 50%.Stress-strain graphs were developed from experimental and finite element analysis *** Young’s modulus and yield strength of the scaffolds were measured from the slop of the stress-strain graph to be 395 and 19.50 MPa respectively for compression,427 and 6.96 MPa respectively for tension,257 and 25.30 MPa respectively for three-point bending and 231 and 12.83 MPa respectively for torsion *** finite element model was found to be in good agreement with the experimental *** fracture of the struct subjected to tensile strain was the main failure mode of the PEEk scaffold,which stems from the low crystallinity of additive manufacturing *** mechanical properties of porous PEEk are close to those of cancellous bone and thus are expected to be used in additive manufacturing PEEk bone implants in the future,but the lower yield strength poses a design challenge.

关键词： additive manufacturing bone scaffold finite element analysis mechanical behaviour lattice structure PEEk scaffold

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