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Biomedical and Environmental Sciences 1992年第3期5卷 241-250页

作者： NIRUPA MAMAllIcK l.c.rai laboratory of Algal Biology Centre of Advanced Study in Botany Banaras Hindu UniversityLaboratory of Algal Biology Centre of Advanced Study in Botany Banaras Hindu University Varanasi 221005 IndiaVaranasi 221005 India

This study demonstrates a concentration dependent inhibition of carbon fixation, O2 evolution, photosynthetic electron transport chain and ATP content of A. doliolum and c. vulgaris by cu, Ni and Fe. Although the mode of inhibition of photosynthetic electron transport chain of both the algae was similar, PS II depicted greater sensitivity to the test metals used. The toxicity in both organisms was cu > Ni > Fe. A. doliolum was, however, more sensitive to cu and Ni, and c. vulgaris to Fe. Toxicity was generally dependent on metal uptake, which in turn was dependent on their concentrations in the external medium. A partial restoration of nutrient uptake, carbon fixation, and enzyme activities following supplementation of exogenous ATP suggests that ATP regulates toxicity through chelation.

关键词： Metal Induced Inhibition of Photosynthesis,Photosynthetic Electron Transport chain and ATP content of Anabaena doliolum and chlorella vulgaris ATP

Heavy Metal Toxicity in a N_2-Fixing cyanobacterium, Anabaena doliolum: Regulation of Toxicity by certain Environmental Factors

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Biomedical and Environmental Sciences 1990年第2期3卷 240-249页

作者： S.K.DUBEY l.c.rai laboratory of Algal Biology Centre of Advanced Study in BotanyBanaras Hindu University Varanasi-221005 India

The toxic effects of chromium and tin salts on growth, ^(14)c uptake, heterocyst differentiation, and nitrate reductase. nitrogenase, and glutamine synthetase activities of Anabaena doliolum and their regulation by pH. salinity, extracellular metabolites (spent), and organic acids have been studied. The toxicity of the test metals was lowered at alkaline pH and increased at acidic pH. Nacl at 20 mM was found to decrease metal toxicity. Extracellular metabolites (spent) in a 1:1 ratio(v/v) with fresh culture medium and organic acids were found to reduce metal toxicity. Among the various organic acids studied, humic acid was the most effective in regulating metal toxicity, apparently due to its multiple binding sites for metal cations. This study demonstrated that environmental *** as pH, salinity, extracellular metabolites, and organic acids, can mediate the toxicity of heavy metals to A. doliolum in a laboratory microcosm, (c)1990 Academic Press. Inc.

关键词： Anabaena doliolum

Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith Jessica l.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

Impact of Spectral Quality on Toxicity of Iron in Anabaena Doliolum and chlorella Vulgaris.

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Biomedical and Environmental Sciences 1992年第1期5卷 65-75页

作者： NIRUPAMA MAllIcK l. c. rai laboratory of Algal Biology Centre of Advanced Study in Botany. Banaras Hindu UniversityLaboratory of Algal Biology Centre of Advanced Study in Botany. Banaras Hindu University Varanasi-221005 IndiaVaranasi-221005 India

Evidence is presented on the effects of low and high concentrations of iron on growth, nutrient uptake (NH4+and NO3-), photosynthesis (cO2-fixation and O2-evolution) and nitrate reductase (NR) activity of A. doliolum and c. vulgaris under monochromatic irradiation. control cultures (not treated with Fecl3) showed maximum growth under fluorescent followed by red, yellow, blue and green lights (fluorescent > yellow > red > blue > green). The inhibition was of synergistic type under yellow and red lights at all the iron concentrations tested. However, under blue and green lights the interaction was less than additive type. All the processes studied responded in a similar manner to a particular color of light. Under fluorescent light at low Fe concentrations, stimulation of NR, 14cO2-fixation and O2-evolution was noticed in both the test organisms. However, even the lowest concentration of iron tested was inhibitory to these processes under yellow and red lights. Under blue light at 20 μg-ml-1 Fe, NR activity was inhibited by 98%. This study clearly demonstrates that metal toxicity to phytoplankton will be greatly affected by spectral quality, hence it will have great significance in limnological research.

关键词： chlorella Anabaena photosynthesis yellow vulgaris lights uptake photosynthetic reductase irradiation

Feature selection for face recognition:a memetic algorithmic approach

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1140-1152页

作者： Dinesh KUMAR Shakti KUMAR c.S.rai Department of computer Science & Engineering Guru Jambheshwar University of Science & Technology Institute of Science and Technology University School of Information Technology GGS Indraprastha University

The eigenface method that uses principal component analysis(PcA) has been the standard and popular method used in face *** paper presents a PcA-memetic algorithm(PcA-MA) approach for feature *** has been extended by MAs where the former was used for feature extraction/dimensionality reduction and the latter exploited for feature *** were performed over ORl and YaleB face databases using Euclidean norm as the *** was found that as far as the recognition rate is concerned,PcA-MA completely outperforms the eigenface *** compared the performance of PcA extended with genetic algorithm(PcA-GA) with our proposed PcA-MA *** results also clearly established the supremacy of the PcA-MA method over the PcA-GA *** further extended linear discriminant analysis(lDA) and kernel principal component analysis(KPcA) approaches with the MA and observed significant improvement in recognition rate with fewer *** paper also compares the performance of PcA-MA,lDA-MA and KPcA-MA approaches.

关键词： Face recognition Memetic algorithm (MA) Principal component analysis (PcA) linear discriminant analysis (lDA) Kernel principal component analysis (KPcA) Feature selection

Traditional Ecological Knowledge and community-based Natural Resource Management in Northeast India

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Journal of Mountain Science 2007年第3期4卷 248-258页

作者： S.c. rai Department of Geography Delhi School of EconomicUniversity of Delhi

community-based natural resource management in northeast India has a long history. Indigenous knowledge and adaptation are the collective information, with improvement from generation to generation. The expectation is that under community control, local expertise on biodiversity will play a significant role in natural resource management through traditional practices. This paper discusses the characteristics and application of the traditional ecological knowledge of aboriginal peoples in northeast India and its role in natural resource management. Examples are provided in two different eco-cultural landscapes, i.e., Demazong (the Buddhist eco-cultural landscape in Sikkim Himalaya) and the Apatani eco-cultural landscape in Arunachal Pradesh, which illustrate the utility value of traditional ecological knowledge in sustainable natural resource management. Both eco-cultural landscapes are indeed very complex and highly evolved systems with high levels of economic and ecological efficiencies. The paper concludes that traditional ecological knowledge systems and institutions could serve as entry points into the sustainable utilization and management of natural resources. This could be achieved through the exploration of the cultural practices of the local people and integrating useful aspects into the modern natural resource management expertise. With rapidly depleting biodiversity in the developing tropic regions, there is a greater utilization today than ever before of the value of respecting the "Sacred" as a tool towards better conservation of natural resources.

关键词： Traditional ecological knowledge resource management cultural landscape sustainable development northeast India

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： carina Hromada Patrick Heimel Markus Kerbl lászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes c.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian cluster for Tissue Regeneration ViennaAustria ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGcs). However, the use of tNGcs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGc would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGcs and compared the various features of these improved silk^(+) tNGcs with the tubes without holes(silk^(–) tNGcs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGcs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGcs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGcs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGcs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

The meridional circulation of the Sun: Observations, theory and connections with the solar dynamo

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Science china(Physics,Mechanics & Astronomy) 2021年第3期64卷 46-72页

作者： Arnab rai choudhuri Department of Physics Indian Institute of ScienceBangalore560012India

The meridional circulation of the Sun, which is observed to be poleward at the surface, should have a return flow at some depth. Since large-scale flows like the differential rotation and the meridional circulation are driven by turbulent stresses in the convection zone, these flows are expected to remain confined within this zone. current observational(based on helioseismology)and theoretical(based on dynamo theory) evidences point towards an equatorward return flow of the meridional circulation at the bottom of the convection zone. Assuming the mean values of various quantities averaged over turbulence to be axisymmetric,we study the large-scale flows in solar-like stars on the basis of a 2D mean field theory. Turbulent stresses in a rotating star can transport angular momentum, setting up a differential rotation. The meridional circulation arises from a slight imbalance between two terms which try to drive it in opposite directions: a thermal wind term(arising out of the higher efficiency of convective heat transport in the polar regions) and a centrifugal term(arising out of the differential rotation). To make these terms comparable,the poles of the Sun should be slightly hotter than the equator. We discuss the important role played by the meridional circulation in the flux transport dynamo model. The poloidal field generated by the Babcock-leighton process at the surface is advected poleward, whereas the toroidal field produced at the bottom of the convection zone is advected equatorward. The fluctuations in the meridional circulation(with coherence time of about 30-40 yr) help in explaining many aspects of the irregularities in the solar cycle. Finally, we discuss how the lorentz force of the dynamo-generated magnetic field can cause periodic variations in the large-scale flows with the solar cycle.

关键词： astrophysical plasma solar physics Sun:solar magnetism Sun:helioseismology fluid flow:rotational

characteristics of Emission Non-nulling Pulsars Through Simulation

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Research in Astronomy and Astrophysics 2024年第4期24卷 91-102页

作者： rai Yuen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key laboratory of Radio Astrophysics Chinese Academy of SciencesUrumqi 830011China Key laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China SIfA School of PhysicsUniversity of SydneySydneyNSW2006Australia

We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar *** from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is ***(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is ***(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the *** find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and ***,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime.

关键词： radiation mechanisms:non thermal stars:neutron (stars:)pulsars:general