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The evolution of the atmosphere in the archaean and early Proterozoic

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chinese Science Bulletin 2011年第1期56卷 4-13页

作者： NISBET Euan FOWLEr c Mary r Deptartment of Earth Sciences Royal HollowayUniversity of London

Key steps in atmospheric evolution occurred in the *** Hadean atmosphere was created by the inorganic processes of volatile accretion from space and degassing from the interior,and then modified by chemical and photochemical *** air was probably initially anoxic,though there may have been a supply of oxidation power as a consequence of hydrodynamic escape to space of hydrogen from *** subduction may have removed cO2 and the Hadean planet may have been *** the archaean,as anoxygenic and then oxygenic photosynthesis evolved,biological activity remade the *** evidence implies there were liquid oceans despite the faint young *** oceans may have been sustained by the greenhouse warming effect of biologically-made *** in the late archaean would have released free O2 into the *** would have created oxic surface waters,challenging the methane *** the Great Oxidation Event around 2.3 to 2.4 billion years ago,the atmosphere itself became oxic,perhaps triggering a glacial crisis by cutting methane-caused greenhouse *** the early Proterozoic,all the key biochemical processes that maintain the modern atmosphere were probably present in the microbial community.

关键词：晚太古代大气演化早元古代二氧化碳温室效应光化学过程微生物群落调制解调器

cold-Sprayed Magnesium coatings Deposited with Helium and Air

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稀有金属材料与工程 2012年第S1期41卷 61-63页

作者： M P Planche r Bolot c coddet LErMPS University of Technology of Belfort-Monbeliard90010Belfort cedexFrance

cold-sprayed magnesium coatings have been little researched although cold spraying has been applied to deposit a large number of materials such as metals,metal matrix *** the present study,helium gas and air were employed as the propelling gases to deposit Mg coatings under the temperature of 600℃and 630℃.The effect of gas types on the coating microstructure was *** is much interesting to find that the particle deposition efficiency using helium gas as propelling gas is lower than that using *** suggests that strong erosion occurred during cold spraying using helium *** porosity of the coating using helium gas is lower than that using *** addition,the in-flight particle velocity was also simulated by the FLUENT software to explore the effect of gas *** modeled results show that the in-flight particle velocity using helium is higher than the erosion velocity of Mg particle.

关键词： cold spraying magnesium coating microstructure particle velocity electrochemical cell

Projections of the impacts of climate change on the water deficit and on the precipitation erosive indexes in Mantaro river Basin, Peru

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Journal of Mountain Science 2018年第2期15卷 264-279页

作者： Sly c.WONGcHUIG carlos r.MELLO Sin c.cHOU Hydraulics Institute research Federal University of Rio Grande do Sul Soil and Water Engineering Federal University of Lavras Brazilian Weather research and for.cast National Spatial Research Institute (INPE)

Projections of climate change are essential to guide sustainable development plans in the tropical Andean countries such as Peru. This study assessed the projections of precipitation and potential evaporation, rain erosive potential, and precipitation concentration in the Mantaro river Basin, in the Peruvian Andes, which is important for.agriculture and energy production in Peru. We assumed the Intergovernmental Panel on climate change （IPcc） AIB greenhouse gas emission scenario and simulated the global climate change by the HadcM3 global climate model. Due to the steepness of the mountain slopes and the narrowness of the river valley, this study uses the downscaling of the global model simulations by the regional Eta model down to 2o-km resolution. The downscaling projections show decrease in the monthly precipitation with respect to the baseline period, especially during the rainy season, between February and April, until the end of the 21st century. Meanwhile, a progressive increase in the monthly evaporation from the baseline period is projected. The Modified Fournier Index （MFI） shows a statistically significant downward trend in the Mantaro river Basin, whieh suggests a possible reduction in the rain erosive potential. The Precipitation concentration Index （PcI） shows a statistically significant increasing trend, which indicates increasingly more irregular temporal distribution of precipitation towards the end of the century. The results of this study allow us to conclude that there should be a gradual increase in water deficit and precipitation concentration. Both changes can be negative for.agriculture, power generation, and water supply in the Mantaro river Basin in Peru.

关键词： Precipitation Evaporation Precipitationconcentration Index (PcI) Modified Fournier Index(MFI) climate change Tropical Andes

Microglial activation and adult neurogenesis after brain stroke

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Neural regeneration research 2021年第3期16卷 456-459页

作者： Ijair r.c.dos Santos Michelle Nerissa c.Dias Walace Gomes-Leal Laboratory of Experimental Neuroprotection and Neuroregeneration Institute of Biological SciencesFederal University of Pará-BrazilBelém-ParáBrazil

The discovery that new neurons are produced in some regions of the adult mammalian brain is a paradigm-shift in neuroscience *** new-born cells are produced from neuroprogenitors mainly in the subventricular zone at the margin of the lateral ventricle,subgranular zone in the hippocampal dentate gyrus and in the striatum,a component of the basal ganglia,even in *** the human hippocampus,neuroblasts are produced even in *** regulation of adult neurogenesis is a complex phenomenon involving a multitude of molecules,neurotransmitters and soluble factors released by different sources including glial ***,the resident macrophages of the central nervous system,are considered to play an important role on the regulation of adult neurogenesis both in physiological and pathological *** stroke and other acute neural disorders,there is an increase in the numbers of neuroblast production in the neurogenic *** activation is believed to display both beneficial and detrimental role on adult neurogenesis after stroke,depending on the activation level and brain *** this article,we review the scientific evidence addressing the role of microglial activation on adult neurogenesis after ischemia.A comprehensive understanding of the microglial role after stroke and other neural disorders it is an important step for.development of future therapies based on manipulation of adult neurogenesis.

关键词： adult neurogenesis hippocampus ischemia microglia neuroinflammation neuroprotection stroke subventricular zone therapy

A rANS-VoF Numerical Model to Analyze the Output Power of An OWc-WEc Equipped with Wells and Impulse Turbines in A Hypothetical Sea-State

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china Ocean Engineering 2020年第6期34卷 760-771页

作者： Paulo r.F.Teixeira rafael A.A.c.Gonçalves Eric Didier Engineering School Universidade Federal do Rio Grande-FURGRio GrandeRS 96203-900Brazil Harbours and Maritime Structures Division Hydraulics and Environment DepartmentLaboratório Nacional de Engenharia Civil-LNECLisbon 1700-066Portugal

Wave energy is a renewable source with significant amount in relation to the global demand. A good concept of a device applied to extract this type of energy is the onshore oscillating water column wave energy converter(OWc-WEc). This study shows a numerical analysis of the diameter determination of two types of turbines, Wells and Impulse, installed in an onshore OWc device subjected to a hypothetical sea state. commercial software FLUENT?,which is based on rANS-VoF(reynolds-Averaged Navier-Stokes equations and Volume of Fluid technique), is employed. A methodology that imposes air pressure on the chamber, considering the air compressibility effect, is used. The mathematical domain consists of a 10 m deep flume with a 10 m long and 10 m wide OWc chamber at its end(geometry is similar to that of the Pico's plant installed in Azores islands, Portugal). On the top of the chamber, a turbine works with air exhalation and inhalation induced by the water free surface which oscillates due to the incident wave. The hypothetical sea state, represented by a group of regular waves with periods from 6 to 12 s and heights from 1.00 to 2.00 m(each wave with an occurrence frequency), is considered to show the potential of the presented methodology. Maximum efficiency(relation between the average output and incident wave powers) of46% was obtained by using a Wells turbine with the diameter of 2.25 m, whereas the efficiency was 44% by an Impulse turbine with the diameter of 1.70 m.

关键词： wave energy oscillating water column Wells turbine Impulse turbine rANS-VoF compressible air

Depressive disorder and antidepressants from an epigenetic point of view

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World Journal of Psychiatry 2022年第9期12卷 1150-1168页

作者： Iris Šalamon arčan Katarina Kouter Alja Videtič Paska Institute of Biochemistry and Molecular Genetics Faculty of MedicineUniversity of LjubljanaLjubljana SI-1000Slovenia

Depressive disorder is a complex,heterogeneous disease that affects approximately 280 million people ***,genetic,and neurobiological factors contribute to the depressive *** the nervous system is susceptible to shifts in activity of epigenetic modifiers,these allow for.significant plasticity and response to rapid changes in the *** the most studied epigenetic modifications in depressive disorder is DNA methylation,with findings centered on the brain-derived neurotrophic factor gene,the glucocorticoid receptor gene,and the serotonin transporter *** order to identify biomarkers that would be useful in clinical settings,for.diagnosis and for.treatment response,further research on antidepressants and alterations they cause in the epigenetic landscape throughout the genome is *** on cornerstone antidepressants,such as selective serotonin reuptake inhibitors,selective serotonin and norepinephrine reuptake inhibitors,norepinephrine,and dopamine reuptake inhibitors and their effects on depressive disorder are available,but systematic conclusions on their effects are still hard to draw due to the highly heterogeneous nature of the *** addition,two novel drugs,ketamine and esketamine,are being investigated particularly in association with treatment of resistant depression,which is one of the hot topics of contemporary research and the field of precision psychiatry.

关键词： Epigenetics Depression DNA methylation Histone tail modification microrNA Antidepressants

camera traps reveal the natural corridors used by mammalian species in eastern Mexico

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Ecological Processes 2022年第1期11卷 711-722页

作者： Jonathan O.Huerta‑rodríguez Octavio c.rosas‑rosas Lauro López‑Mata JoséL.Alcántara‑carbajal Luis A.Tarango‑arámbula Programa de recursos Genéticos y Productividad‑Ganadería Colegio de Post‑graduadosCampus MontecilloTexcocoMexico Programa de Innovación en Manejo de recursos Naturales Colegio de PostgraduadosCampus San Luis PotosíSan Luis PotosíMexico Programa de Dinámica y conservación de Bosques y Selvas Macroecología y BiodiversidadColegio de PostgraduadosCampus MontecilloTexcocoMexico

Background:Habitat loss and fragmentation in the Sierra Madre Oriental(SMO)ecological corridor have negative impacts on the movement and distribution of mammalian species that are of great ecological and evolutionary *** of the SMO ecological corridor that is located in the state of Hidalgo is less studied despite being a potential dispersal route for.*** objectives of this study were to evaluate the presence and activity of terrestrial mammals in the riparian and non‑riparian zones of ***:camera traps detected 15 mammalian species(i.e.,14 native and 1 domestic)in the non‑riparian zone,and 12 mammalian species in the riparian zone(i.e.,10 wild and 2 domestic).The riparian corridor was mainly used by opportunistic medium‑sized carnivores,while large carnivores and their potential prey were more frequent in the non‑riparian ***:Our findings suggest terrestrial mammals avoid the use of natural corridors due to the presence of domestic dogs,cattle and humans and look for.new dispersal routes to move through their habitat and find the resources they need to *** though some species can use disturbed corridors to move and find resources,they will change their activity patterns to avoid contact with humans and potential threats like *** is,therefor.,crucial to identify not one,but several corridors that must be preserved to improve the connectivity of terrestrial mammals in disturbed landscapes.

关键词： Activity Jaguar cattle Detectability Dog Herbivore Disturbance Prey relative abundance

Flow resistance of gravel bed channels

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International Journal of Sediment research 2014年第1期29卷 126-132页

作者： Wen c.WANG David r.DAWDY Multech Engineering consultants

Existing resistance for.ulas produce a wide range of friction-factor estimates for.gravel bed *** purpose of this paper is to develop a reliable resistance for.ula in terms of the Darcy-Weisbach friction factor/ Published data were screened and used to establish the *** existing for.ulas have considered that/is a function of relative roughness D84/r only,where r is the hydraulic radius and D84is the particle size referred to the intermediate diameter that equals or exceeds that of 84 percent of bed *** this paper,/is considered as a function of Froude number in addition to the relative roughness./for.D84/r>1 displays a different trend than that for.D84/rrhaps due to the invalid assumption of a logarithmic velocity distribution for.D84/r>***/for.ula for.D84/r<1 has been established.

关键词： Flow resistance Darcy-Weisbach friction factor relative roughness relative submergence Gravel bed channels Open channels

Following a TrAIL: Update on a ligand and its five receptors

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cell research 2004年第5期14卷 359-372页

作者： Fiona c. KIMBErLEY,Gavin r. ScrEATON Weatherall Institute of Molecular Medicine Human Immunology Unit John radcliffe Hospital Oxfor. OX3 9DS UK Department of Medicine Hammersmith Hospital Imperial college Du cane road London W12 0NN UK.

Identification of tumour necrosis factor apoptosis inducing ligand (TrAIL), a TNF family ligand, sparked a torrent of research, following an initial observation that it could kill tumour cells, but spare normal cells. Almost a decade after its discovery, and with five known receptors, the true physiological role of TrAIL is still debated and its anti-tumorigenic properties limited by potential toxicity. This review takes a comprehensive look at the story of this enigmatic ligand, addressing its remaining potential as a therapeutic and providing an overview of the TrAIL receptors themselves.

关键词： TrAIL apoptosis cancer.