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Legumes from the Paleocene sediments of India and their ecological significance

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Plant Diversity 2023年第2期45卷 199-210页

作者： Harshita Bhatia Gaurav Srivastava R.c.mehrotra Birbal Sahni Institute of Palaeosciences 53 University RoadLucknow 226007India Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India

During the early Paleogene,greenhouse gases created warm global *** warm climates redistributed the habitat of marine and terrestrial biota *** the ecology of biotas under extremely warm climates is important to decipher their behavior in future climate *** we report two new legume fossils(Leguminocarpum meghalayensis Bhatia,Srivastava et mehrotra ***.,and Parvileguminophyllum damalgiriensis Bhatia,Srivastava et mehrotra ***.) from the late Paleocene sediments of Tura Formation of meghalaya,northeast ***,the Paleocene legume fossil records indicate that legumes most likely immigrated to India from Africa via the Ladakh-Kohistan Arc during the early ***,previously reconstructed climate data from the Tura Formation indicate that legumes were well adapted to a warm seasonal climate with monsoon rains.

关键词： Fabaceae Global warming Fruits Damalgiri Tura Rhynchosia

APPROXImATE cONTROLLABILITY RESULTS FOR INTEGRO-QUASILINEAR EVOLUTION EQUATIONS VIA TRAJEcTORY REAcHABLE SETS

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Acta mathematica Scientia 2020年第2期40卷 412-424页

作者： A.Vinodkumar c.Loganathan S.Vijay Department of mathematics Amrita School of EngineeringAmrita Vishwa VidyapeethamCoimbatore-641112India Department of mathematics Maharaja Arts and Science CollegeCoimbatore-641407Tamil NaduIndia

In this article,we study the approximate controllability results for an integroquasilinear evolution equation with random impulsive moments under sufficient *** results are obtained by the theory of c0 semigroup of bounded linear operators on evolution equations and using trajectory reachable ***,we generalize the results too with and without fixed type impulsive moments.

关键词： Integro-quasilinear control system random impulses approximate controllability

Effects of the phase variation and high-order momentum transfer components of NN amplitude on p-~4He elastic scattering

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Nuclear Science and Techniques 2018年第1期29卷 65-76页

作者： I.m.A.Tag-Eldin m.m.Taha S.S.A.Hassan Nuclear Experimental Physics Department Nuclear Research Center Atomic Energy Authority mathematics and Theoretical Physics Department Nuclear Research Center Atomic Energy Authority

Elastic scattering differential cross sections for a p- ~4He system are calculated within the framework of optical limit approximation of the Glauber multiple scattering model. Three different ranges for proton energy(E_(lab)), 19〈E_(lab)〈50 me V, 100≤E_(lab)≤1730 me V, and 45 ≤E_(lab)≤393 Ge V are considered. It is shown that the Pauli blocking fails to describe the data up to the proton energy, E_(lab)〈100 me V. For higher proton energies, a qualitative agreement is obtained. The observed elastic scattering differential cross section is nicely reproduced in the whole range of scattering angles in the center of mass system up to Θ_(c.m.)〈200° for 19〈E_(lab) ≤100 me V when the effect of both the nucleon–nucleon(NN) phase variation parameter γNN and higher-order momentum transfer components(λ_n; n = 1 and 2) of(NN) elastic scattering amplitude is included. In the range of 200 E_(lab) 1730 me V, introducing λ_n plays a significant role in describing the data up to the momentum transfer, q^2≤1:2(Ge V/c)~***, it is found that considering only the effect of phase variation parameter, cNN, improved the agreement in the region of minima for elastic scattering differential cross section for 45≤E_(lab)≤393 Ge V. The values of cNNand kn as a function of incident proton energies are presented.

关键词： Elastic scattering Optical limit approximation Glauber multiple scattering model

Growth Kinetics of Nanocrystals and Nanorods by Employing Small-angle X-ray Scattering (SAXS) and Other Techniques

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Journal of materials Science & Technology 2008年第4期24卷 615-627页

作者： Kanishka BISWAS Neenu VARGHESE c.N.R.Rao chemistry and Physics of materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India Solid State and Structural Chemistry UnitIndian Institute of ScienceBangalore 560012India chemistry and Physics of materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India

In this article, we report the results of our detailed investigations of the growth kinetics of zero-dimensional nanocrystals as well as one-dimensional nanorods by the combined use of small angel X-ray scattering （SAXS）, transmission electron microscopy （TEm） along with other physical techniques. The study includes growth kinetics of gold nanocrystals formed by the reduction of HAucl4 by tetrakis（hydroxymethyl） phosphonium chloride in aqueous solution, of cdSe nanocrystals formed by the reaction of cadmium stearate and selenium under solvothermal conditions, and of ZnO nanorods formed by the reaction of zinc acetate with sodium hydroxide under solvothermal conditions in the absence and presence of capping agents. The growth of gold nanocrystals does not follow the diffusion-limited Ostwald ripening, and instead follows a Sigmoidal rate curve. The heat change associated with the growth determined by isothermal titration calorimetry is about 10 kcal·mol^-1 per I nm increase in the diameter of the nanocrystals. In the case of cdSe nanocrystals also, the growth mechanism deviates from diffusion-limited growth and follows a combined model containing both diffusion and surface reaction terms. Our study of the growth kinetics of uncapped and poly（vinyl pyrollidone）（PVP）-capped ZnO nanorods has yielded interesting insights. We observe small nanocrystals next to the ZnO nanorods after a lapse of time in addition to periodic focusing and defocusing of the width of the length distribution. These observations lend support to the diffusion-limited growth model for the growth of uncapped ZnO nanorods. Accordingly, the time dependence on the length of uncapped nanorods follows the L3 law as required for diffusion-limited Ostwald ripening. The PVP-capped nanorods, however, show a time dependence, which is best described by a combination of diffusion （L^3） and surface reaction （L^2） terms.

关键词： Growth kinetics Gold nanocrystals cdSe nanocrystals ZnO nanorods Small angle X-ray scattering Transmission electron microscopy Ostwald ripening and sigmoidal growth

Bonding of compound casted Ti/Al bimetal by heat treatment

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International Journal of minerals,metallurgy and materials 2021年第9期28卷 1515-1524页

作者： m.Fadaeinia Ramin Raiszadeh Department of metallurgy and materials Science School of EngineeringShahid Bahonar University of KermanKerman ***Iran

The formation mechanism of the bonding between compound cast Al/Ti bimetal during a heat treatment regime was *** pure Al was cast and melt on a Ti bar in a steel tube,followed by heat treatment on the compound cast Ti/Al bimetal for different periods of time once the Al melt was *** bonding was observed between the two metals after the initial casting,which can be attributed to the presence of oxide films on the liquid Al and solid Ti alloys and the trapped atmosphere between *** effect of these layers in preventing the formation of bonding was eliminated after heat treating the cast part at~973 K(~700℃)for at least 15 min,and the metals started to bond with each other.A detailed description of this bonding mechanism is presented in this paper.

关键词： compound casting titanium/aluminium bimetal bonding

Impact of carbon-based nutrient enhancement on biofiltration performance for drinking water treatment

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Journal of Environmental Sciences 2019年第8期31卷 124-131页

作者： Yu Zhao Liz Taylor-Edmonds Robert c.Andrews Department of civil and mineral Engineering University of Toronto

Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters that were operated in parallel and individually enhanced with amino acids(including alanine, phenylalanine, and tryptophan), inulin, and sucrose to increase biomass concentration and promote biodegradation of dissolved organic carbon(DOc) in the source water, including disinfection by-product(DBP) precursors. Biomass activity was characterized by measuring adenosine tri-phosphate(ATP), dissolved oxygen(DO) consumption, and through the use of laccase and esterase enzyme assays. Performance was evaluated in terms of headloss,turbidity, p H, DOc, UV254, and DBP formation potential(DBP FP). The introduction of carbonbased nutrients significantly increased biomass activity, where ATP values peaked at 976 ng/g of filter media, 853 ng/g, and 513 ng/g for amino acids, inulin, and sucrose-spiked biofilters,respectively, while a non-spiked control only reached 104 ng/g. DO utilization by the enhanced biofilters was significantly higher than the control, with a strong correlation between ATP and DO uptake observed for all filters(R^2> 0.74). Laccase and esterase enzyme activities of enhanced biofilters were also elevated(p > 0.05), suggesting greater biodegradation potential. Operational parameters such as headloss development and turbidity control were not impaired by carbon supplementation strategies or an increase in biomass concentration and activity. However, the enhancement strategy did not provide improvement in terms of source water carbon removal(DOc and UV254) or DBP FP when treated filters were compared to a control.

关键词： Biological filtration carbon enhancement Biomass Disinfection by-products Dissolved organic carbon

Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction

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Acta mechanica Sinica 2017年第2期33卷 243-249页

作者： J. Wei c. Dong B. chen Department of Engineering mechanics Zhejiang UniversityHangzhou 310058 China

We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can be negative cross-bridges resisting contraction within the sarcomere and higher ATP concentration would decrease the resistance force from negative cross-bridges by promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is above a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors.

关键词： motor force regulation ATP muscle contraction myosin

Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

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Neural Regeneration Research 2023年第12期18卷 2573-2581页

作者： Sílvia Sousa chambel célia Duarte cruz Experimental Biology Unit Department of BiomedicineFaculty of Medicine of PortoUniversity of PortoPortoPortugal Translational NeuroUrology Instituto de Investigação e Inovação em Saúde-i3S and IBMCUniversidade do PortoPortoPortugal

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROcK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory prot

关键词： chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19

The use of the node-based smoothed finite element method to estimate static and seismic bearing capacities of shallow strip footings

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Journal of Rock mechanics and Geotechnical Engineering 2022年第1期14卷 180-196页

作者： H.c.Nguyen T.Vo-minh Department of civil and environmental engineering imperial college londonuk Department of civil engineering and industrial design university of liverpoolliverpooluk Faculty of civil engineering ho chi minh city university of technology(hutech)ho chi minh cityviet nam

The node-based smoothed finite element method(NS-FEm)is shortly presented for calculations of the static and seismic bearing capacities of shallow strip footings.A series of computations has been performed to assess variations in seismic bearing capacity factors with both horizontal and vertical seismic *** results obtained agree very well with those using the slip-line method,revealing that the magnitude of the seismic bearing capacity is highly dependent upon the combinations of various directions of both components of the seismic *** upward vertical seismic acceleration reduces the seismic bearing capacity compared to the downward vertical seismic acceleration in *** addition,particular emphasis is placed on a separate estimation of the effects of soil and superstructure inertia on each seismic bearing capacity *** the effect of inertia forces arising in the soil on the seismic bearing capacity is non-trivial,and the superstructure inertia is the major contributor to reductions in the seismic bearing *** tables and charts are given for practical application to the seismic design of the foundations.

关键词： Limit analysis Node-based smoothed finite element method(NS-FEm) Second-order cone programming(SOcP) Seismic bearing capacity Strip footing