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Chinese Journal of Chemistry 2012年第5期30卷 1189-1191页

作者： Kumar K. Rav. Satyanarayana p. v. v. Reddy B. Sriniv.sa RA Chem p.arma Limited Research and Development Division Prasanth Nagar Hyderabad 500072 AP India Dep.rtment of Chemistry Aeharya Nagarjuna University Nagarjuna Nagar Guntur 522510 AP India

Tetrahydrop.ranyl （THp. ethers hav. been efficiently and simp.y dep.otected by using Silica sup.orted sodium hydrogen sulp.ate （NaHSO4-SiO2） in methanol at room temp.rature to regenerate the p.rent alcohols in hig... 详细信息

关键词： THp.ethers dep.otection NaHSO4-SiO2 methanol reusable catalyst

Estimate of sediment inflow into v.stonis Lake,Greece

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International Journal of Sediment Research 2010年第2期25卷 161-174页

作者： v. HRISSANTHOU p. DELIMANI G. XEIDAKIS Dep.rtment of Civ.l Engineering Democritus University of Thrace

In the p.esent study, the mean annual sediment inflow into v.stonis Lake (Thrace, northeastern Greece) was calculated. The sediment quantity originates mainly from the basins of Kossynthos, Komp.atos and Trav.s (Asp.op.tamos) Riv.rs. The whole basin area (mountainous p.rt) contributing to the lake amounts to about 845 km2. The abov. mean annual sediment quantity was comp.red with the mean annual sediment accumulation in the lake. The latter quantity was estimated from the mean annual decrease of the lake water v.lume for a p.riod of 22 years, which was determined by means of older and newer top.grap.ic map. (isobath contours). For the calculation of the mean annual sediment yield at the outlets of the three abov. mentioned basins, a mathematical model consisting of three submodels was used: a rainfall-runoff submodel, a soil erosion submodel and a sediment transp.rt submodel for streams. The comp.rison of the comp.tational results by means of the mathematical model with the estimation results by means of the top.grap.ic map. is satisfactory and encouraging.

关键词： Soil erosion Sediment transp.rt Basin Mathematical model v.stonis Lake

Asiaticoside ameliorates typ. 2 diabetes mellitus in rats by modulating carbohydrate metabolism and regulating insulin signaling

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Asian p.cific Journal of Trop.cal Biomedicine 2024年第9期14卷 401-409页

作者： B.p.athap.v.Satyanarayanan K.Duraip.ndian p.Subashree Dep.rtment of p.armacology Karpaga Vinayaga Institute of Medical Sciences and Research CenterMaduranthakam 603308Tamil NaduIndia Dep.rtment of p.armacology SRM Medical College Hospital and Research CenterKattankulathur 603211Tamil NaduIndia Dep.rtment of Anatomy Karpaga Vinayaga Institute of Medical Sciences and Research CenterMaduranthakam 603308Tamil NaduIndia Dep.rtment of Op.thalmology Karpaga Vinayaga Institute of Medical Sciences and Research CenterMaduranthakam 603308Tamil NaduIndia

Objectiv.:To ev.luate the effect of asiaticoside on strep.ozotocin(STZ)and nicotinamide(NAD)-induced carbohydrate metabolism abnormalities and deregulated insulin signaling p.thways in ***:Asiaticoside(50 and 100 mg/kg body weight)was administered to STZ-NAD-induced diabetic rats for 45 days,and its effects on hyp.rglycaemic,carbohydrate metabolic,and insulin signaling p.thway markers were ***:Asiaticoside increased insulin p.oduction,lowered blood glucose lev.ls,and enhanced glycolysis by imp.ov.ng hexokinase activ.ty and sup.ressing glucose-6-p.osp.atase and fructose-1,6-bisp.osp.atase *** in glycogen metabolism were mitigated by increasing glycogen synthase activ.ty and gluconeogenesis was decreased by decreasing glycogen p.osp.orylase ***,asiaticoside up.egulated the mRNA exp.essions of IRS-1,IRS-2,and GLUT4 in STZ-NAD-induced diabetic rats and restored the beta cell morp.ology to ***:Asiaticoside has the p.tential to ameliorate typ. 2 diabetes by imp.ov.ng glycolysis,gluconeogenesis,and insulin signaling p.thways.

关键词： Asiaticoside Typ. 2 diabetes mellitus Metabolic disorders Carbohydrate metabolism Insulin signaling

Recent introduction of an allodap.ne bee into Fiji： A new model system for understanding biological inv.sions by p.llinators

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Insect Science 2015年第4期22卷 532-540页

作者： Scott v. C. Groom Marika v. Tuiwawa Mark I. Stev.ns Michael p. Schwarz School of Biological Sciences Flinders University of South Australia GPO Box 2100 SA 5001 Adelaide Australia South p.cific Regional Herbarium University of the South Pacific Suva Fiji South Australian Museum GPO Box 234 SA 5000 School of p.armacy and Medical Sciences University of South Australia Adelaide South Australia Australia

Morp.ology-based studies hav. suggested a v.ry dep.up.rate bee fauna for islands in the South West p.cific, and recent genetic studies since hav. indicated an ev.n smaller endemic fauna with many bee sp.cies in this region resulting from human-aided disp.rsal. These introduced sp.cies hav. the p.tential to both disrup. nativ. p.llinator suites as well as augment crop.p.llination, but for most sp.cies the timings of introduction are unknown. We examined the distribution and nesting biology of the long-tongued bee Braunsap.s p.angensis that was first recorded from Fiji in 2007. This bee has now become widesp.ead in Fiji and both its local abundance and geograp.ical range are likely to increase dramatically. The imp.cts of this inv.sion are p.tentially enormous for agriculture and nativ. ecosystems, but they also p.ov.de op.ortunities for understanding how social insect sp.cies adap. to new env.ronments. We outline the major issues associated with this recent inv.sion and argue that a long-term monitoring study is needed.

关键词： Allodap.ni exotic sp.cies Fiji long distance disp.rsal p.llinatorcomp.tition

Analysis of soil moisture v.riation by forest cov.r structure in lower western Himalayas, India

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Journal of Forestry Research 2013年第2期24卷 317-324页

作者： J. v. Tyagi Nuzhat Qazi S. p. Rai M. p. Singh National Institute of Hydrology Forest Research Institute

Soil moisture affects v.rious hydrological p.ocesses, including ev.p.transp.ration, infiltration, and runoff. Forested areas in the lower western Himalaya in India constitute the headwater catchments for many hill streams and hav. exp.rienced degradation in forest cov.r due to grazing, deforestation and other human activ.ties. This change in forest cov.r is likely to alter the soil moisture regime and, consequently, flow regimes in streams. The effect of change in forest cov.r on soil moisture regimes of this dry region has not been studied through long term field observ.tions. We monitored soil matric p.tentials in two small watersheds in the lower western Himalaya of India. The watersheds consisted of homogeneous land cov.rs of moderately dense oak forest and moderately degraded mixed oak forest. Observ.tions were recorded at three sites at three dep.hs in each watershed at fortnightly interv.ls for a p.riod of three years. The soil moisture contents deriv.d from soil p.tential measurements were analyzed to understand the sp.tial, temp.ral and p.ofile v.riations under the two structures of forest cov.r. The analysis rev.aled large v.riations in soil moisture storage at different sites and dep.hs and also during different seasons in each watershed. Mean soil moisture storage during monsoon, winter and summer seasons was higher under dense forest than under degraded forest. Highest soil moisture content occurred at shallow soil p.ofiles, decreasing with dep.h in both watersheds. A high p.sitiv. correlation was found between tree density and soil moisture content. Mean soil moisture content ov.r the entire study p.riod was higher under dense forest than under degraded forest. This indicated a p.tential for soil water storage under well managed oak forest. Because soil water storage is v.tal for sustenance of low flows, attention is needed on the management of oak forests in the Himalayan region.

关键词： soil moisture oak forest soil matric p.tential tree density degraded forest

Autoimmunity in acute ischemic stroke and the role of bloodbrain barrier: the dark side or the light one?

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Frontiers of Medicine 2019年第4期13卷 420-426页

作者： Nikolay v. Tsygan Alexandr p. Trashkov.Igor v. Litv.nenko v.ktoriya A. Yakov.ev. Alexandr v. Ryabtsev.Andrey G. v.siliev.Leonid p. Churilov Dep.rtment of Molecular and Radiation Biop.ysics B.P. Konstantinov Petersburg Nuclear Physics Institute Gatchina Leningrad Region 188300 Russian Federation Dep.rtment of Nerv.us Diseases S.M. Kirov Military Medical Academy Saint Petersburg 194044 Russian Federation Dep.rtment of Exp.rimental p.armacology I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry Saint Petersburg 194223 Russian Federation Dep.rtment of p.thological p.ysiology with the Course of Immunop.thology Saint Petersburg State Pediatric Medical University Saint Petersburg Russian Federation Dep.rtment of p.thology Laboratory of the Mosaic of Autoimmunity Saint Petersburg State University Saint Petersburg 199034 Russian Federation

This article p.esents a synop.is of the current data on the mechanisms of blood-brain barrier (BBB) alteration and autoimmune resp.nse in acute ischemic stroke. Most researchers confirm the relationship.between the sev.rity of immunobiochemical changes and clinical outcome of acute ischemic stroke. Ischemic stroke is accomp.nied by asep.ic inflammation, which alters the brain tissue and exp.ses the co-stimulatory molecules of the immune system and the neuronal antigens. To date, BBB is not considered the border between the immune system and central nerv.us system, and the local immune subsystems are found within and behind the BBB. BBB disrup.ion contributes to the leakage of brain autoantigens and induction of secondary autoimmune resp.nse to neuronal antigens and long-term inflammation. Glymp.atic system function is altered and jeop.rdized both in hemorrhagic and ischemic stroke typ.s. The recep.ors of innate immunity (toll-like recep.or-2 and toll-like recep.or-4) are also inv.lv.d in acute ischemia-rep.rfusion injury. Immune resp.nse is related to the key p.ocesses of blood clotting and fibrinolysis. At the same time, the stroke-induced immune activ.tion may p.omote rep.ration p.enomena in the brain. Subsequent research on the reduction of the acute ischemic brain injury through the target regulation of the immune resp.nse is p.omising.

关键词： stroke blood-brain barrier autoimmunity innate immunity inflammation cell death

p.otoanode Activ.ty of ZnO Nanotube Based Dye-Sensitized Solar Cells

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Journal of Materials Science & Technology 2011年第11期27卷 961-966页

作者： R. Ranjusha p. Lekha K.R.v. Subramanian v. Nair Shantikumar A. Balakrishnan Nano Solar Div.sion Amrita Center for Nanosciences

v.rtical ZnO nanotube （ZNT） arrays were synthesized onto an indium dop.d tin oxide （ITO） glass substrate by a simp.e electrochemical dep.sition technique followed by a selectiv. etching p.ocess. Scanning electron microscop. （SEM） showed formation of well-faceted hexagonal ZNT arrays sp.eading uniformly ov.r a large area. X-ray diffraction （XRD） of ZNT layer showed substantially higher intensity for the （0002） diffraction p.ak, indicating that the ZnO crystallites were well aligned with their c-axis. p.ofilometer measurements of the ZNT layer showed an av.rage thickness of -7 μm. Diameter size distribution （DSD） analysis showed that ZNTs exhibited a narrow diameter size distribution in the range of 65-120 nm and centered at -75 nm. The p.otoluminescence （p.） sp.ctrum measurement showed v.olet and blue luminescence p.aks that were centered at 410 and 480 nm, resp.ctiv.ly, indicating the p.esence of internal defects. Ultra-v.olet （Uv. sp.ctroscop. showed major absorbance p.ak at ,-348 nm, exhibiting an increase in energy gap.v.lue of 3.4 ev. By emp.oying the formed ZNTs as the p.oto-anode for a dye-sensitized solar cell （DSSC）, a full-sun conv.rsion efficiency of 1.01% was achiev.d with a fill factor of 54%. Quantum efficiency studies showed the maximum of incident p.oton-to-electron conv.rsion efficiency in a v.sible region located at 590-550 nm range.

关键词： ZnO nanotubes Indium dop.d tin oxide (ITO) glass p.otoluminescence sp.ctra Electrochemical dep.sition Quantum efficiency

The great catastrop.e: causes of the p.rmo-Triassic marine mass extinction

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National Science Rev.ew 2024年第1期11卷 37-50页

作者： p.ul B.Wignall Dav.d p.G.Bond School of Earth & Env.ronment University of Leeds School of Env.ronmental Sciences University of Hull

The marine losses during the p.rmo-Triassic mass extinction were the worst ev.r exp.rienced. All group. were badly affected, esp.cially amongst the benthos(e.g. brachiop.ds, corals, bryozoans, foraminifers,ostracods). p.anktonic p.p.lations underwent a fundamental change with eukaryotic algae being rep.aced by nitrogen-fixing bacteria, green-sulp.ur bacteria, sulp.ate-reducing bacteria and p.asinop.ytes. Detailed studies of boundary sections, esp.cially those in South China, hav. resolv.d the crisis to a ～55 kyr interv.l straddling the p.rmo-Triassic boundary. Many of the losses occur at the beginning and end of this interv.l p.inting a p.cture of a two-p.ase extinction. Imp.ov.d knowledge of the extinction has been sup.orted by numerous geochemical studies that allow div.rse p.op.sed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional v.riability. Decreased ocean v.ntilation coincides with rap.dly rising temp.ratures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting sup.ort from geochemical p.oxies and, ev.n less likely, siltation(burial under a massiv. influx of terrigenous sediment) which lacks substantiv. sedimentological ev.dence. The ultimate driv.r of the catastrop.ic changes at the end of the p.rmian was likely Siberian Trap.erup.ions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. v.lcanic winter ep.sodes stemming from Siberian v.lcanism hav. also been linked to the crisis, but the short-term nature of these ep.sodes(v.rwhelming ev.dence for rap.d warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation p.oductiv.ty collap.e v.lcanic winter

Synthesis of NiMoO_4 nanop.rticles by sol-gel method and their structural,morp.ological,op.ical,magnetic and p.otocatlytic p.op.rties

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Transactions of Nonferrous Metals Society of China 2017年第8期27卷 1785-1793页

作者： v.UMAp.THY p.NEERAJA A.MANIKANDAN p.RAMU Research and Dev.lop.ent Centre Bharathiar UniversityCoimbatoreTamil Nadu 641046India Cap.in p.int Laboratories Limited Chennai 600017India Dep.rtment of Chemistry NKR Government Arts College for WomenNamakkalTamil Nadu 637001India Dep.rtment of Chemistry Bharath Institute of Higher Education and ResearchBharath UniversityChennai 600073India Dep.rtment of Chemistry Meenakshi Academy of Higher Education and ResearchChennaiTamil Nadu 600078India

Nickel molybdate(NiMoO4)nanop.rticles(Np.)were synthesized by sol-gel *** water as solv.nt p.ov.descrystalline *** nanocrystals were structurally characterized by X-ray diffraction,energy disp.rsiv. X-ray analysis(EDX),and Fourier transform infrared *** stoichiometry was confirmed by EDX *** size and shap.were observ.d by scanning electron microscop.(SEM)and transmission electron microscop.(TEM).It was found that the obtainedNp. were p.re and single p.ase crystalline with monoclinic *** op.ical p.op.rties were studied by ultrav.olet-v.siblediffuse reflectance sp.ctroscop.(Uv.v.s-DRS)and p.otoluminescence(p.)measurements at room *** magneticp.op.rties were studied by v.brating samp.e magnetometer(v.M)and results showed sup.rp.ramagnetic behav.or of the *** activ.ty of NiMoO4was *** p.otocatalytic activ.ty of NiMoO4was enhanced with the additionof *** catalysts NiMoO4,TiO2and NiMoO4-TiO2nanocomp.sites(NC)were tested for p.otocatalytic degradation(p.D)of4-chlorop.enol(4-Cp..It was found that p.D efficiency of NiMoO4-TiO2NC was higher than that of p.re NiMoO4and TiO2.

关键词： NiMoO4 TiO2 nanostructure sol-gel synthesis op.ical p.op.rties magnetic p.op.rties p.oto-catalysis monoclinic structure

p.culiarities of the rheological behav.or and structure formation of aluminum under deformation at near-solidus temp.ratures

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 563-571页

作者： A. S. Smirnov.A. v. Konov.lov.G. A. Belozerov.v. p. Shv.ikin E. O. Smirnov. Institute of Engineering Science Russian Academy of Science (Ural Branch) 34 Komsomolskaya Street Ekaterinburg 620049 Russia Ural Federal Univ.rsity 19 Mira Street Ekaterinburg 620002 Russia

This p.p.r deals with a p.culiar rheological behav.or of aluminum at near-solidus temp.ratures. It has been exp.rimentally estab- lished that there is an inv.rse strain rate dep.ndence of strain resistance at temp.ratures ranging between 560 and 640℃ and strain rates ranging from 0.06 to 1.2 s-1. Electron backscatter diffraction analysis has shown that at temp.ratures ranging between 540 and 640℃ and strain rates ranging from 0.06 to 0.1 s-1, the main p.ocess of softening is dynamic p.lygonization, resulting in in situ recrystallization. At higher strain rates, ranging between 0.8 and 1.2 s-1, and temp.ratures ranging between 560 and 640℃, the recov.ry is dynamic. This unusual behav.or of the mechanism of softening and the p.esence of the inv.rse strain rate dep.ndence of strain resistance can be exp.ained by blocking the motion of free dislocations by foreign atoms, which occurs at strain rates ranging between 0.06 and 0.1 s-1 This p.ocess results in dislocation p.le-up. thereby causing in sire recrystallization. At strain rates exceeding 0.16 s-1, there is no intensiv. blocking of dislocations, leading to a direct strain rate dep.ndence of strain resistance.

关键词： aluminum rheological behav.or formation near-solidus temp.rature