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Climate and fire drivers of forest composition and openness in the Changbai Mountains since the Late Glacial

森林生态系统:英文版 2023年第4期10卷 448-458页

作者： Meng Meng Sandy p.Harrison Dongmei Jie Nannan Li Baojian Liu Dehui Li Guizai Gao Honghao Niu School of Geographical Sciences Northeast Normal UniversityChangchun130024China Geography&Environmental Science University of ReadingWhiteknightsReadingRG66AHUK Leverhulme Centre for Wildfires Environment and SocietyImperial College LondonSouth KensingtonLondonSW72BWUK Key Laboratory of Geographical processes and Ecological Security in Changbai Mountains Ministry of EducationChangchun130024China Institute for peat and Mire Research State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation RestorationNortheast Normal UniversityChangchun130024China Key Laboratory for Vegetation Ecology Ministry of EducationChangchun130024China HaiZhou Senior High School Lianyungang222023China College of Resources and Environment Hebei Normal UniversityShijiazhuang050010China School of Archaeology Jilin UniversityChangchun130015China

Ongoing climate changes have a direct impact on forest growth;they also affect natural fire regimes,with further implications for forest *** of how these will affect forests on decadal-to-centennial timescales is *** we use reconstructions of past vegetation,fire regimes and climate during the Holocene to examine the relative importance of changes in climate and fire regimes for the abundance of key tree species in northeastern *** reconstructed vegetation changes and fire regimes based on pollen and charcoal records from Gushantun *** then used generalized linear modelling to investigate the impact of reconstructed changes in summer temperature,annual precipitation,background levels of fire,fire frequency and fire magnitude to identify the drivers of decadal-to-centennial changes in forest openness and *** in climate and fire regimes have independent impacts on the abundance of the key tree *** variables are generally more important than fire variables in determining the abundance of individual *** is the only determinant of forest openness,but summer temperature is more important than precipitation for individual tree taxa with warmer summers causing a decrease in cold-tolerant conifers and an increase in warmth-demanding broadleaved *** background level and fire frequency have negative relationships with the abundance of most tree taxa;only pinus increases as fire frequency *** magnitude of individual fires does not have a significant impact on species abundance on this *** climate and fire regime characteristics must be considered to understand changes in forest composition on the decadal-to-centennial *** are differences,both in sign and magnitude,in the response of individual tree species to individual drivers.

关键词： Forest composition Climate change Fire regime Fire frequency Changbai Mountains Holocene Generalized linear model

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A NOVEL SYNTHETIC METHOD FOR THE CLUSTERS FeCo_2(CO)_9- (RCCR)(R=MeO_2C,EtO_2C).X-RAY CRYSTAL STRUCTURE ANALYSESOF THE CLUSTERS FeCo_2(CO)_9(MeO_2CCCCO_2Me) and Co_4(CO)_(10)-(EtO_2CCCCO_2Et)

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Chinese Chemical Letters 1996年第6期7卷 585-588页

作者： Wu H.p. Yin Y.Q. Yu K.B. Huang X.Y. Lanzhou Inst. of Chemical physics Chinese Academy of Sciences Lanzhou 730000 Chengdu Anal. Determination Center Chinese Academy of Sciences Chengdu 610041 Fuzhou Inst. Res. Struct. of Matter Chinese Academy of Sciences State Key Lab. of Struct. Chemistry Fuzhou 350002

A novel synthetic method for the clusters FeCo2(CO)9(RCCR)(R=MeO2C,MeO2C), which isthe reaction of Co4(CO)10(RCCR) with Na2[Fe(CO)4], have been found by studying on tile thermal reactionbetween RCCo3(CO)9 with Na2[Fe(CO)4]. X-ray crystal structural determinations have been made for theclusters FeCo2(CO)9(MeO2CCCCO2Me) and Co4(CO)10(EtO2CCCCO2Et)

关键词： CO FeCo2 RCCR ANALYSES CLUSTERS

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A multicast routing algorithm with multiple trees

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Journal of Systems Engineering and Electronics 2005年第2期16卷 426-432页

作者： Cui Xunxue 1,2 , Gao Wei3 & Fang Hongyu41. New Star Research Institute of Applied Technology, Hefei 230031, p. R. China 2. Jiangsu Key Laboratory of Computer Information processing Technology,Soochow University, Suzhou 215006, p. R. China 3. Department of Electronic Engineering and Information Science,University of Science and Technology of China, Hefei 230027, p. R. China 4. School of Electronic Science and Technology, Anhui University, Hefei 230039, p. R. China New Star Research Institute of Applied Technology Hefei 230031 P. R. China 2. Jiangsu Key Laboratory of Computer Information processing Technology Soochow University Suzhou 215006 P. R. China Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei 230027 P. R. China School of Electronic Science and Technology Anhui University Hefei 230039 P. R. China

Quality of service (QoS) multicast routing has continued to be a very important research topic in the Internet. A method of multicast routing is proposed to simultaneously optimize several parameters based on multiobjective genetic algorithm, after the related work is reviewed. The contribution lies on that the selection process of such routing is treated with multiobjective optimization. Different quality criterions in Ip network are taken into account for multicast communications. A set of routing trees is generated to approximate the pareto front of multicast problem. Multiple trees can be selected from the final set of nondominated solutions, and applied to obtain a good overall link cost and balance traffic distribution according to some simulation results.

关键词： multicast routing quality of service multiobjective optimization genetic algorithms.

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Mesenteric traction syndrome in pigs:A single-blinded,randomized controlled trial

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Animal Models and Experimental Medicine 2021年第2期4卷 162-168页

作者： Rune B.Strandby Jens T.F.Osterkamp Rikard Ambrus Amelie Henriksen Jens p.Goetze Niels H.Secher Michael p.Achiam Lars-Bo Svendsen Department of Surgical Gastroenterology RigshospitaletUniversity of CopenhagenCopenhagenØDenmark Department of Clinical Biochemistry RigshospitaletUniversity of CopenhagenCopenhagenØDenmark Department of Anaesthesia RigshospitaletUniversity of CopenhagenCopenhagenØDenmark

Background:Mesenteric traction syndrome is commonly observed in patients undergoing upper abdominal surgery and is associated with severe postoperative complications.A triad of hypotension,tachycardia,and facial flushing seems provoked by prostacyclin(pGI 2)release from the gut in response to mesenteric *** administration of nonsteroidal anti-inflammatory drugs(NSAID)inhibits pGI 2 release,stabilizing the hemodynamic ***,we examined the effect of mesenteric traction on splanchnic blood flow in pigs randomized to NSAID or placebo *** and Methods:Twenty pigs were allocated to either ketorolac or pla-cebo *** minutes of manual mesenteric traction was *** 6-keto-pGF1,a stable metabolite of pGI 2,hemodynamic variables,and regional blood flow(laser speckle contrast imaging)to the liver,stomach,small intestine,upper lip,and snout(laser Doppler flowmetry)were recorded prior to traction and 5 and 30 minutes ***:Both groups of pigs presented a decrease in systemic vascular resistance(p.01),mean arterial blood pressure(p.001),and blood flow in the gastric an-trum(p.002).plasma 6-keto-pGF1 did not increase in either group(p.195),and cardiac output,heart rate,central venous pressure,and blood flow to the liver,small intestine,upper lip,and snout remained ***:Mesenteric traction resulted in cardiovascular depression,including re-duced blood flow in the gastric *** 6-keto-pGF1 did not increase,and ketorolac administration did not alter the response to mesenteric *** studies are needed to identify which substance is responsible for eliciting the cardio-vascular response to mesenteric traction in pigs.

关键词： 6-keto-pGF1 gastric blood flow hemodynamics laser speckle contrast imaging mesenteric traction syndrome prostacyclin

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One step synthesis of pyrido[1,2-a]benzimidazole derivatives of aryloxypyrazole and their antimicrobial evaluation

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Chinese Chemical Letters 2013年第2期24卷 123-126页

作者： Hardik H.Jardosh Chetan B.Sangani Manish p.patel Ranjan G.patel Department of Chemistry Sardar Patel UniversityVallabh Vidyanagar-388120GujaratIndia

Received 3 September 2012 Received in revised form 16 October 2012 Accepted 31 December 2012 Available online 6 February 2013

关键词： Aryloxypyrazolepyrido[ 1 2-a]benzimidazoleMulticomponent reactionAntimicrobial activity

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Design and dynamic simulation of hydraulic system of a new automatic transmission

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Journal of Central South University 2009年第4期16卷 697-701页

作者：王书翰徐向阳刘艳芳戴振坤 TEN BERGE p 曲巍 School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Institute for Engineering Design and powertrain Technologies Chemnitz University of Technology

A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic system of AT was established by ITI-SimulationX. Simulation results and theoretical design results were compared to confirm the simulation model. Based on the confirmed simulation model, the simulation results of pressure and flow of the hydraulic system were analyzed. The dynamic simulation method is very helpful for designing and analyzing the performance of hydraulic system and further optimization design. The theoretical design method and dynamic simulation model are feasible for the real industrial applications. The research results can be used in hydraulic system design and optimization.

关键词： automatic transmission hydraulic system dynamic simulation

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FRECKLE FORMATION AND CHARACTERIZATION OF A Ni-Cr-Mo-Fe-W ALLOY

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 414-418页

作者： J.X.Dong M.C.Zhang Y.p.Zeng X.S.Xie University of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 China

The freckle formation and their phase characterization in freckle areas were investigated by means of microstructure analysis approaches and a thermodynamic equilibrium phase calculation method in a Ni-Cr-Mo-Fe-W alloy. These results show that in freckle areas a large number of M6C, μ and p phases precipitate in grain boundaries even within grain due to the enrichment and segregation of Mo and C during solidification, which results in small grains in freckle areas. Equilibrium phase and liquid segregation calculation can give an reasonable interpretation of the freckle feature for this alloy.

关键词： freckle Ni-Cr-Mo-Fe- W alloy thermodynamic calculation

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COVID-19 rebound after oral treatment in a nursing home facility:A case series

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Infectious Medicine 2022年第4期1卷 285-287页

作者： Alex p.Betrosian Stavros M.Christou Stavroula Kalathaki Evgenidion Hospital Athens UniversityPapadiamantopoulou 2011527 AthensGreece Kallisto Skilled Nursing Facility AthensGreece

paxlovid(nirmatrevir/ritonavir)is a 2 drug regimen taken together twice daily for 5 days was authorized for emergency use for nonhospitalized patients who are at risk for the progression of coronavirus disease(COVID-19).However,recurrence of symptoms 2–8 days after completing the treatment course has been recently *** some cases patients tested negative on a direct SARS-CoV-2 viral test and then tested positive again(rebound COVID-19).The disease is mild and requires no additional antiviral *** are limited based on anecdotal case reports and few *** to the available data it is unclear if rebound symptoms are due to the drug treatment,drug resistance,re-infection or impaired immunity.

关键词： COVID-19 Infection paxlovid Nursing facility

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First observation of microspherule from the infratrappean Gondwana sediments below Killari region of Deccan LIp,Maharashtra(India) and possible implications

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Geoscience Frontiers 2019年第6期10卷 2281-2285页

作者： G.parthasarathy O.p.pANDey B.Sreedhar Mukund Sharma priyanka Tripathi Nimisha Vedanti CSIR-National Geophysical Research Institute Hyderabad500007India National Institute of Advance Studies School of Natural Sciences and EngineeringIndian Institute of Science CampusBengaluru560012India CSIR-Indian Institute of Chemical Technology Hyderabad500007India Birbal Sahni Institute of palaeosciences 53 University RoadLucknow226007India presently at Banaras Hindu University VaranasiIndia Geological Survey of India BandalagudaHyderabad50068India

A rare occurrence of a microspherule has been found in the infratrappean sediments,encountered below338 m thick Deccan volcanic cover in KLR-1 scientific borehole,drilled in the epicentral zone of the 1993 Killari earthquake(Maharashtra,India).palynological studies of the sediments indicate their age as Early permian(Asselian,298-295 Ma) for *** electron microscope studies reveal that the spherule from the infratrappeans,is having a similar composition to that of the Neoarchean amphibolite to granulite facies mid crustal *** spherule is non-spherical in nature,containing mostly FeO(10.70±0.20 wt.%),CaO(13.8±0.5 wt.%),Al203(7.78±0.30 wt.%),MgO(6.47±0.3 wt.%),Si02(47,46±0.50 wt.%),Ti02(2.47±0.3 wt.%).K20(1.89±0.20 wt.%).and Cl(0.33±0.05 wt.%).Since the Fe composition of the spherule is almost same as the basement rock(10.5 wt.%),and the chlorine content is also in the same range as the basement(0.04-0.24 wt.%),it would suggest possibility of an extraterrestrial impact over the Indian terrain during the erstwhile Gondwana sedimentation period that may be associated with the permian-Triassic mass extinction,the most severe one in the Earth's history.

关键词： Deccan trap Killari borehole Microspherules Condwana sediments Tectonics p-T impact

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Constitutive modeling of flow behavior of precipitation-hardened AA7022-T6 aluminum alloy at elevated temperature

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Transactions of Nonferrous Metals Society of China 2020年第11期30卷 2927-2940页

作者： H.R.REZAEI ASHTIANI p.SHAHSAVARI School of Mechanical Engineering Arak University of TechnologyArakIran

The thermomechanical behavior of precipitation-hardened aluminum alloy AA7022-T6 was studied using isothermal compression at temperatures of 623−773 K and strain rates of 0.01−1 s^−*** experimental results indicated that dynamic recrystallization(DRX)is a predominant hot deformation mechanism,especially at elevated temperatures and low strain *** modified Johnson−Cook(J−C)and the strain compensated Arrhenius-type models were developed to predict the hot flow behavior under different deformation *** correlation coefficients of modified J−C model and the strain compensated Arrhenius-type models were 0.9914 and 0.9972,respectively,their average relative errors(ARE)were 6.074%and 4.465%,respectively,and their root mean square errors(RMSE)were 10.611 and 1.665 Mpa,respectively,indicating that the strain compensated Arrhenius-type model can predict the hot flow stress of AA7022-T6 aluminum alloy with an appropriate accuracy.

关键词： flow behavior constitutive models Arrhenius model dynamic recrystallization AA7022-T6 aluminum alloy

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