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Split nitrogen application increases maize root growth,yield,and nitrogen use efficiency under soil warming conditions 被引量:2
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作者 Zhenqing Xia Yuxiang Gong +3 位作者 Xiangyue Lyu Junchen Lin Yi Yang Haidong Lu 《The Crop Journal》 2025年第2期565-575,共11页
The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e... The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress. 展开更多
关键词 Maize(Zea mays L.) Soil warming Split nitrogen application Root growth Nitrogen use efficiency Grain yield
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Data-Driven Prediction in Complex Systems of Virus Evolution and Global Warming 被引量:1
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作者 LUO Liaofu LÜJun 《内蒙古大学学报(自然科学版)》 2025年第1期1-7,共7页
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da... A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500. 展开更多
关键词 data-drivenprediction complex system virus evolution global warming
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Effects of Warm Rolling on the Microstructure and Mechanical Properties of Low-Cr FeCrAl Alloys at Room and Elevated Temperatures
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作者 CHEN Gangming WANG Hui HUANG Xuefei 《材料导报》 北大核心 2025年第9期178-188,共11页
The effects of different warm rolling(WR)reductions on the microstructure and mechanical properties of low-Cr FeCrAl alloys at both room and elevated temperatures were investigated.The study revealed that when the WR ... The effects of different warm rolling(WR)reductions on the microstructure and mechanical properties of low-Cr FeCrAl alloys at both room and elevated temperatures were investigated.The study revealed that when the WR reduction is small,it effectively refines the grains and forms a large number of subgrains in the matrix,while also inducing the dissolution of the Laves phase.This enhances the mechanical properties of FeCrAl alloys primarily through grain refinement and solid solution strengthening.Conversely,with larger WR reductions,the grain refinement effect diminishes,but a significant number of Laves phases form in the matrix,strengthening the alloys primarily through precipitation strengthening.WR exhibited a remarkable enhancing effect on the comprehensive mechanical properties at both room and high temperatures,with a signi-ficant enhancement in ductility at high temperatures.Notably,a 10%WR reduction resulted in the optimal overall mechanical properties at both room and elevated temperatures. 展开更多
关键词 FeCrAl alloy low-Cr warm rolling Laves phases mechanical property
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Causes of co-existence of cool-temperate Fagus and warm-loving evergreen Quercus forests in central Italy during the Holocene thermal maximum
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作者 Giorgia Beffa Erika Gobet +11 位作者 Sevil Cosgun Riccardo Dotta Luc Hachler Marina Alexandra Morlock Laura Sadori Patrick Schlafli Christoph Schworer Lieveke van Vugt Hendrik Vogel Paul David Zander Martin Grosjean Willy Tinner 《Forest Ecosystems》 2025年第5期894-908,共15页
Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for c... Mediterranean forest communities are particularly diverse but at risk due to their sensitivity to global warming.Understanding the long-term vulnerability of Mediterranean vegetation to climate change is crucial for conservation and management purposes.Studies on past changes of forest communities in response to climate change at ecologically meaningful resolutions(i.e.,decadal time scales) are therefore essential,but still very rare.The Holocene thermal maximum(HTM;ca.10,000-5,000 cal years before the present(BP)) may be used to study species and community responses to warmer conditions than during recent decades.We performed highresolution multiproxy palaeoecological analyses on sediments from crater Lake Mezzano in central Italy to reconstruct vegetation,diversity,and fire dynamics between 8,450 and 7,050 cal years BP.Ordination,crosscorrelation,and species-response analyses were used to investigate the response of Mediterranean forest communities to HTM climate warming,human impact,and fire.Vegetational changes prior to 7,450 cal years BP were driven by climate.Fagus sylvatica spread into mixed deciduous oak forests during the Early Holocene in response to declining seasonality(cooler summers and warmer winters).Subsequently,Fagus sylvatica declined and evergreen Quercus ilex expanded after 8,200 cal years BP when the climate became warmer.Although reduced,Fagus sylvatica remained important together with deciduous oaks.The co-existence of Fagus sylvatica and evergreen Quercus forests is extremely rare today.Human impact significantly affected forest vegetation after7,450 cal years BP,when Neolithic agricultural activities became important,ultimately extirpating these special communities but fostering the overall biodiversity.However,their past occurrence in several central Italian calderas during the HTM suggests that these environments provided habitats that permitted the thriving of cooltemperate forests of Fagus sylvatica under mesomediterranean conditions,with summers ca.1-2℃ warmer than today.Cool and moist calderas may thus become increasingly important for maintaining Mediterranean mesophilous forest species under global warming conditions. 展开更多
关键词 PALAEOECOLOGY Plant-climate interactions Biodiversity Climate warming Mediterranean Continuous time series
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Rivers increasingly warmer:Prediction of changes in the thermal regime of rivers in Poland
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作者 Mariusz PTAK Teerachai AMNUAYLOJAROEN Mariusz SOJKA 《Journal of Geographical Sciences》 2025年第1期139-172,共34页
Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has... Emphasis on future environmental changes grows due to climate change,with simulations predicting rising river temperatures globally.For Poland,which has a long history of thermal studies of rivers,such an approach has not been implemented to date.This study used 9 Global Climate Models and tested three machine-learning techniques to predict river temperature changes.Random Forest performed best,with R^(2)=0.88 and lowest error(RMSE:2.25,MAE:1.72).The range of future water temperature changes by the end of the 21st century was based on the Shared Socioeconomic Pathway scenarios SSP2-4.5 and SSP5-8.5.It was determined that by the end of the 21st century,the average temperature will increase by 2.1°C(SSP2-4.5)and 3.7°C(SSP5-8.5).A more detailed analysis,divided by two major basins Vistula and Odra,covered about 90%of Poland's territory.The average temperature increase,according to scenarios SSP2-4.5 and SSP5-8.5 for the Odra basin rivers,is 1.6°C and 3.2°C and for the Vistula basin rivers 2.3°C and 3.8°C,respectively.The Vistula basin's higher warming is due to less groundwater input and continental climate influence.These findings provide a crucial basis for water management to mitigate warming effects in Poland. 展开更多
关键词 global warming forecasting water temperature Poland
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Warming-Induced Increase in Flooding in the Taklimakan Desert
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作者 Yanan Su Xin Wang +5 位作者 Xiangjun Luo Shengqian Chen Yaqi Chen Fan Yang Jiaqiang Lei Fahu Chen 《Journal of Earth Science》 2025年第3期1351-1354,共4页
The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average a... The Taklimakan Desert,located in the heart of central Asia,covers approximately 330000 km^(2),making it China's largest desert and the world's second-largest shifting desert(Dong et al.,2024).With an average annual precipitation of less than 100 mm and evaporation rates ranging from 2000 to 3000 mm(Yang et al.,2020),it is recognized as one of the driest regions on Earth,often referred to as the“sea of death”. 展开更多
关键词 evaporation rates warming induced dry region evaporation precipitation Taklimakan Desert shifting desert FLOODING
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Central Asian Compound Flooding in 2024 Contributed by Climate Warming and Interannual Variability
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作者 Wenxia ZHANG Lan LI +4 位作者 Tianjun ZHOU Michael BRODY Qing HE Min XU Azamat MADIBEKOV 《Advances in Atmospheric Sciences》 2025年第10期2195-2202,共8页
Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and ca... Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions. 展开更多
关键词 compound flooding SNOWMELT extreme rainfall soil moisture climate warming interannual variability
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A Rare Elevated Thunderstorm Crossing over the North Pole Associated with an Arctic Warming Event
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作者 Di XU Baohua REN +3 位作者 Gaopeng LU Hailiang HUANG Jianqiu ZHENG Lanxin KOU 《Advances in Atmospheric Sciences》 2025年第6期1179-1194,共16页
In August 2019,accompanied by an Arctic warming event,elevated thunderstorms crossed over the North Pole(NP)and produced lightning.The northernmost stroke occurred less than 50 km from the NP,marking the closest strok... In August 2019,accompanied by an Arctic warming event,elevated thunderstorms crossed over the North Pole(NP)and produced lightning.The northernmost stroke occurred less than 50 km from the NP,marking the closest stroke to the NP ever recorded.Using ERA5 reanalysis data and satellite observations,we investigated the background and development mechanism of this event.Warm and moist air from low latitudes was transported northward to the vicinity of the North Pole by the 850-h Pa jet,resulting in convergence.Through the combined effects of frontal lifting and the presence of underlying cold air,the warm and moist air was lifted to heights above the melting layer,triggering elevated thunderstorms above the frontal boundary.These findings describe a strong link between warming events and thunderstorms,revealing the formation mechanisms of elevated thunderstorms in the Arctic.In the context of rapid Arctic warming,this study provides preliminary insights into the meteorological conditions conducive to thunderstorm formation in the region. 展开更多
关键词 Arctic warming elevated thunderstorm low-level jet frontal lift
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Natural Drivers of Global Warming:Ocean Cycles,Anthropogenic Greenhouse Gases and the Question of Percentages
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作者 Peter J.Taylor 《Journal of Environmental & Earth Sciences》 2025年第2期262-290,共29页
There is a widespread policy assumption that anthropogenic greenhouse gases are the main driver of the observed 1°C rise in global surface air temperatures since‘pre-industrial’times.This paper demonstrates tha... There is a widespread policy assumption that anthropogenic greenhouse gases are the main driver of the observed 1°C rise in global surface air temperatures since‘pre-industrial’times.This paper demonstrates that the onset of the current warming trend began in the mid-19th century and is consistent with the rising phase of variable global warming and cooling cycles in both the Northern and Southern Hemispheres.Hemispheres.The last trough of the millennial cycle,the Little Ice Age,coincides approximately with the baseline of pre-industrial times used to calculate the impact of Anthropogenic Global Warming.Yet,half of the observed 20th century temperature rise occurred before 1950 when carbon dioxide levels remained low,with the remaining half happening at a similar rate of warming despite the much higher concentrations of greenhouse gases in the atmosphere.This study shows that when the amplitudes and rates of change of the long-term global cycles are considered,the anthropogenic component of warming can be reduced to 38%(using factors derived from the latest IPCC Working Group reports)to as little as 25%(using observational flux data of dominant Short Wave Absorbed Surface Radiation).These global climate cycles can be extrapolated into the future and the implications for policy of a large natural component to climate change are explored—in particular,the potential for mitigation strategies to have minimal impact and for the climate to cool consequent upon a cyclic down-phase. 展开更多
关键词 Global warming Ocean Oscillations Natural Cycles Environmental Policy
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Rapid escalation and release of risks to forest ecosystems triggered by warming:Insights from tree growth synchrony in temperate forests
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作者 Liangjun Zhu Danyang Yuan +5 位作者 J.Julio Camarero David J.Cooper Mai-He Li Shuguang Liu Xiaochun Wang Paolo Cherubini 《Forest Ecosystems》 2025年第4期769-780,共12页
Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapi... Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapidly and slowly warming periods in ecosystems with varying climatic conditions remains limited.By using tree-ring data from temperate broadleaf(Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Juglans mandshurica)and Korean pine(Pinus koraiensis)mixed forests in northeast China,we investigated the effects of climate change,particularly warming,on the growth synchrony of five dominant temperate tree species across contrasting warm-dry and cool-wet climate conditions.Results show that temperature over water availability was the primary factor driving the growth and growth synchrony of the five species.Growth synchrony was significantly higher in warm-dry than in cool-wet areas,primarily due to more uniform climate conditions and higher climate sensitivity in the former.Rapid warming from the 1960s to the 1990s significantly enhanced tree growth synchrony in both areas,followed by a marked reversal as temperatures exceeded a certain threshold or warming slowed down,particularly in the warm-dry area.The growth synchrony variation patterns of the five species were highly consistent over time,although broadleaves exhibited higher synchrony than conifers,suggesting potential risks to forest resilience and stability under future climate change scenarios.Growing season temperatures and non-growing season temperatures and precipitation had a stronger positive effect on tree growth in the cool-wet area compared to the warm-dry area.High relative humidity hindered growth in the cool-wet area but enhanced it in the warm-dry area.Overall,our study highlights that the diversity and sensitivity of climate-growth relationships directly determine spatiotemporal growth synchrony.Temperature,along with water availability,shape long-term forest dynamics by affecting tree growth and synchrony.These results provide crucial insights for forest management practice to enhance structural diversity and resilience capacity against climate changeinduced synchrony shifts. 展开更多
关键词 Tree rings Growth synchrony Forest resilience Rapid warming Temperate forest Northeast China
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A 2.6 GPa Ultra-Strong Steel with Ultrafine Lamellar Structure Produced by Heavy Warm Rolling
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作者 Yutao Wang Liming Fu +2 位作者 Shuo Ma Wei Wang Aidang Shan 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1613-1627,共15页
An ultra-strong steel with enhanced ductility and ultrafine lamellar structure was produced by heavy warm rolling(HWR)of metastable austenite and subsequent quenching.The HWR steel exhibited an ultrahigh yield strengt... An ultra-strong steel with enhanced ductility and ultrafine lamellar structure was produced by heavy warm rolling(HWR)of metastable austenite and subsequent quenching.The HWR steel exhibited an ultrahigh yield strength of 1.09 GPa and an ultimate tensile strength of 2.6 GPa,with a total elongation of 6.7%at room temperature.The high yield strength was primarily attributed to the synergistic strengthening of high-density dislocations,nanotwins,and ultrafine martensite grains with an average effective grain size of 1.02μm.The enhanced ductility is attributed to the parallel lamellar structure,which increased the work-hardening capacity and resulted in delamination toughening.Compared to the heavy multistage rolling(HMR)process,which starts rolling at higher temperatures,the HWR method employed in this study demonstrates significant enhancements in both strength and ductility.Following a 150℃ low-temperature tempering for 1 h,the yield strength of HWR steel was further increased to 2.2 GPa,and the total elongation improved to 10.1%. 展开更多
关键词 Ultra-strong steel Heavy warm rolling Ultrafine lamellar structure MARTENSITE Strength-ductility combination
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Global warming intensifies once-in-a-decade extreme precipitation in summer in China
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作者 Aoqi Zhou Chaoxia Yuan 《Atmospheric and Oceanic Science Letters》 2025年第4期48-53,共6页
The intensification of extreme precipitation(EP)under global warming presents a substantial risk to human safety and societal progress.Studying the specific impacts of global warming on rare EP events in China not onl... The intensification of extreme precipitation(EP)under global warming presents a substantial risk to human safety and societal progress.Studying the specific impacts of global warming on rare EP events in China not only enhances the comprehension of these shifts,but also paves the way for the development of proactive strategies to alleviate associated damages.Results from large-ensemble simulation data demonstrate that global warming has led to an enhancement in once-in-a-decade EP events in parts of western and central China over the past few decades,with the strengthening of the South Asia high(SAH)caused by global warming playing a dominant role.The strengthening of the SAH corresponds to an intensification and westward extension of the western Pacific subtropical high in the lower troposphere.The region between these two systems experiences enhanced upward motion and increased southwesterly water vapor transport,leading to a rise in climatological precipitation in western and central China,thereby raising the threshold for once-in-a-decade EP events. 展开更多
关键词 Global warming Extreme precipitation Climatological precipitation South Asia high
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Changes in tropical cyclone response to the Boreal Summer Intraseasonal Oscillation in the western North Pacific under global warming in EC-Earth3P-HR
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作者 Zhefan Gao Chaoxia Yuan 《Atmospheric and Oceanic Science Letters》 2025年第2期22-28,共7页
EC-Earth3P-HR reproduces well the observed Boreal Summer Intraseasonal Oscillation(BSISO)and its impacts on tropical cyclone genesis(TCG)in the western North Pacific(WNP).Hence,the historical simulation(1950-1979)and ... EC-Earth3P-HR reproduces well the observed Boreal Summer Intraseasonal Oscillation(BSISO)and its impacts on tropical cyclone genesis(TCG)in the western North Pacific(WNP).Hence,the historical simulation(1950-1979)and future projection under the SSP5-8.5 scenario(2020-2049)in EC-Earth3P-HR are adopted to explore possible changes in the BSISO’s modification of WNP TCG under global warming to enhance the understanding of TC activities in the WNP.Results show that the BSISO circulation in the WNP shifts northeastward under global warming.This leads to enhanced convection in a northwest-southeast-oriented band crossing the WNP.Along the band,the BSISO-related TCG anomalies are enhanced.Analyses of genesis potential index show that changes in the BSISO-related mid-tropospheric relative humidity play the dominant role in modifying the BSISO’s impacts on WNP TCG under global warming.The enhanced BSISO convection in the band moistens the middle troposphere,which helps reduce the entrainment of generally dry mid-tropospheric air in the updrafts and the modification of the boundary layer by the downdraft of generally dry mid-tropospheric air,leading to enhanced TCG. 展开更多
关键词 Global warming Tropical cyclones BSISO
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Effects of Climate Warming on Resting Metabolic Rate and Metabolic Enzyme Activities of Takydromus septentrionalis
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作者 Jixiang ZHANG Cheng QIN +4 位作者 Yubin TIAN Jiahuan WANG Shuran LI Yongpu ZHANG Weiguo DU 《Asian Herpetological Research》 2025年第2期202-209,共8页
The dependence of energy metabolism on temperature is universally recognized as a critical physiological hallmark for evaluating the susceptibility of ectothermic organisms to global warming.However,the underlying phy... The dependence of energy metabolism on temperature is universally recognized as a critical physiological hallmark for evaluating the susceptibility of ectothermic organisms to global warming.However,the underlying physiological and biochemical bases of this temperature dependence remain largely unknown.In this study,we conducted a simulated climate warming experiment under seminatural enclosure conditions and compared the differences in resting metabolic rate (RMR) and key metabolic enzyme activities between the warming and control groups of Takydromus septentrionalis at various test temperatures.We found that the activities of hexokinase,lactate dehydrogenase,alanine aminotransferase and acetyl-CoA carboxylase of T.septentrionalis were not affected by climate warming,despite a decrease in RMR measured at high temperatures of 34°C and 38°C.Overall,these findings suggest that artificial warming simulating climate change can lead to a decline in RMR,but does not alter the activity of key metabolic enzymes.Our study provides insight into how climate warming influences the energy metabolism of lizards. 展开更多
关键词 climate warming metabolic enzyme physiological plasticity resting metabolic rates
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Binary-medium-based macro-meso constitutive model for warm frozen soils
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作者 Qiong Li Enlong Liu +3 位作者 Fulong Ma Bingtang Song Dan Wang Pan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5922-5938,共17页
Due to the high water content in warm frozen soil,the pore water pressure and pore ice pressure generated within the sample during loading significantlyinfluencethe deformation and strength of the soil skeleton.Theref... Due to the high water content in warm frozen soil,the pore water pressure and pore ice pressure generated within the sample during loading significantlyinfluencethe deformation and strength of the soil skeleton.Therefore,it is essential to develop a constitutive model for warm frozen soil that can capture the changes in ice pressure and water pressure.This study introduces a macro-meso constitutive model based on a binary-medium framework to describe the mechanical behavior of warm frozen soil.In this model,warm frozen soil is conceptualized as consisting of bonded and frictional elements from a meso perspective.The bonded elements are modeled using a macro-meso elastic constitutive approach based on poromechanics,while the frictional elements employ a macro-meso elastoplastic approach,also grounded in poromechanics.These two elements are then linked within the binarymedium model framework.By replicating the experimental curves of warm frozen soils,the theoretical results from the proposed model show excellent agreement with experimental data.This consistency indicates that the model effectively simulates the strain softening and volumetric expansion behaviors of warm frozen soil samples under various conditions.Additionally,the constitutive model predicts changes in unfrozen water pressure,frozen temperature,unfrozen water saturation,and porosity during the loading process of warm frozen soil samples. 展开更多
关键词 warm frozen soil POROMECHANICS Binary-medium model Macro-meso constitutive model
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Improving mechanical properties of extrusion additive manufacturing WC-9Co cemented carbide via green warm isostatic pressing
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作者 Cai CHEN Run-xing ZHOU +4 位作者 Zu-ming LIU Yong-xia LI Dan ZOU Yi-ming CHANG Xu-lin CHENG 《Transactions of Nonferrous Metals Society of China》 2025年第3期902-920,共19页
To tackle the common issue of green defects in material extrusion(MEX)additive manufacturing(AM)cemented carbides,warm isostatic pressing(WIP)was introduced to eliminate defects of MEX WC-9Co cemented carbide greens,t... To tackle the common issue of green defects in material extrusion(MEX)additive manufacturing(AM)cemented carbides,warm isostatic pressing(WIP)was introduced to eliminate defects of MEX WC-9Co cemented carbide greens,thereby improving both microstructure uniformity and mechanical properties of sintered bodies.The results indicate that WIP reduces defects in MEX greens,thus decreasing the dimensions and numbers of defects,modifying shapes of pores within sintered bodies,while preserving surface quality and shape characteristics.Compared with WC-9Co prepared via MEX followed by debinding and sintering(DS),the hardness of WC-9Co prepared using MEX-WIP-DS does not change significantly,ranging HV_(30)1494-1508,the transverse rupture strength increases by up to 49.3%,reaching 2998-3514 MPa,and the fracture toughness remains high,ranging 14.8-17.0 MPa·m^(1/2).The mechanical properties surpass comparable cemented carbides fabricated through other AM methods and are comparable to those produced by powder metallurgy.The integration of green WIP into MEX-DS broadens the MEX processing window,and improves the overall mechanical properties of MEX AM WC-Co cemented carbides. 展开更多
关键词 material extrusion additive manufacturing WC-Co cemented carbide warm isostatic pressing DEFECT microstructure mechanical properties
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Greening of Eurasia's center driven by low-latitude climate warming
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作者 Shijie Wang Feng Chen +7 位作者 Youping Chen Max C.A.Torbenson Jan Esper Xiaoen Zhao Mao Hu Heli Zhang Weipeng Yue Honghua Cao 《Forest Ecosystems》 2025年第4期728-741,共14页
Central Asia,located in the innermost part of the Eurasian continent,has experienced“warming and humidification”in recent decades,with potentially important implications for tree growth in alpine forests,which are c... Central Asia,located in the innermost part of the Eurasian continent,has experienced“warming and humidification”in recent decades,with potentially important implications for tree growth in alpine forests,which are critical for regional water reserves.We use nested principal component analysis to assess tree radial growth patterns and reveal significant positive trends since the 20th century across Central Asian alpine forests(0.076 per decade during 1900-2021,p=0.003).Regional hydroclimatic variations affect the greening of these alpine forests,especially with extreme droughts being the most damaging.Growth acceleration is driven by low-latitude warming,which enhances regional temperatures and precipitation.The warming ocean centers alter atmospheric circulation patterns,leading to more moisture being transported to the Central Asian alpine forests,thereby increasing regional precipitation and promoting tree growth.Our model projections indicate that growth rates will continue to rise in the future.However,unprecedented warming may eventually lead to growth deterioration if negative effects,such as insufficient precipitation,occur due to breakdown signs of positive feedback mechanisms,such as moisture transport driven by low-latitude warming.Our study highlights the beneficial,but not unlimited,influences of climate warming on tree growth in Central Asian alpine forests,with implications for the sustainability of water resources.However,as urban and agricultural demands escalate,a holistic,long-term perspective is recommended to mitigate the adverse effects of temperature increases. 展开更多
关键词 Central asian alpine forests Tree radial growth Resilience Low-latitude warming Atmospheric circulations Future projection
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Anthropogenic Global Warming Versus Natural Global Warming:An Overview on Global Marine and Terrestrial Biodiversity
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作者 SONG Jingjing CHOONG Khai Hang +2 位作者 TAN Kianann KWAN Kit Yue TAN Karsoon 《Journal of Ocean University of China》 2025年第4期1027-1038,共12页
Climate change is a natural phenomenon.Over the past billions of years,Earth’s climate has experienced many ice and warm periods.These changes have created various environments,directly benefiting and disadvantaging ... Climate change is a natural phenomenon.Over the past billions of years,Earth’s climate has experienced many ice and warm periods.These changes have created various environments,directly benefiting and disadvantaging certain species,eventually leding to extinction and evolutionary diversification through natural selection.However,rapid and drastic changes in Earth’s climate could be destructive and may lead to mass extinction.It is generally believed that four of the five mass extinction events were caused by drastic changes in the level of atmospheric greenhouse gases.In the recent period(the Anthropocene epoch),when human activi-ties began to significantly impact the Earth’s climate,numerous pieces of scientific evidence indicate that anthropogenic activities are associated with the extinction of plants and animals and may lead to the sixth mass extinction.However,some scientists deny the pos-sibility of the 6th mass extinction.Therefore,there is an urgent need to comprehensively review the impact of anthropogenic global warming on our natural environment.This article reviews the scientific evidence of the synergistic impact and chain effects of anthro-pogenic global warming on ecosystems and living organisms on Earth.It earnestly attempts to summarize relevant data published for specific research questions to improve the understanding of diverse evidence.This helps clarify the current state of research and rai-ses public awareness of the impact of anthropogenic global warming on all stakeholders on Earth. 展开更多
关键词 Anthropogenic global warming mass extinction carbon dioxide climate tipping points
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Clinical observation on the effect of warming meridian medicinal wine,polarized light external application combined with acupuncture and moxibustion on pain after vertebroplasty
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作者 WEN Zhigang LU Shuai CHENG Xiumei 《Journal of Traditional Chinese Medicine》 2025年第3期660-666,共7页
OBJECTIVE:To evaluate the effects of external application of warm meridian medicated wine and polarized light therapy combined with acupuncture on pain management following vertebroplasty. METHODS:A total of 120 patie... OBJECTIVE:To evaluate the effects of external application of warm meridian medicated wine and polarized light therapy combined with acupuncture on pain management following vertebroplasty. METHODS:A total of 120 patients with osteoporotic vertebral compression fractures treated by vertebroplasty at our hospital were divided into four groups. The control group received non-steroidal anti-inflammatory drugs, the Treatment Group Ⅰ received acupuncture alone, Treatment Group Ⅱ was treated with medicated wine for warming meridians alongside polarized light physiotherapy, and Treatment Group Ⅲ received a combination of medicated wine for warming meridians, polarized light therapy, and acupuncture. The clinical efficacy, pain thresholds at various time points, temperature pain threshold, electric pain threshold, quality of life, sleep quality index, lumbar dysfunction index, visual analog scale(VAS) scores, and incidence of adverse reactions were compared and analyzed across the four groups. RESULTS:The total clinical effective rate in Treatment Group Ⅲ was significantly higher than that in the control group, Treatment Group Ⅰ, and Treatment Group Ⅱ(P < 0.05). At 24 and 72 h post-treatment, the VAS scores, temperature pain thresholds, and electric pain thresholds in Treatment Group Ⅲ were significantly lower than those in the control group, Treatment Group Ⅰ, and Treatment Group Ⅱ(P < 0.05). Additionally, quality-of-life scores in Treatment Group Ⅲ were markedly higher compared to the control group, Treatment Group Ⅰ, and Treatment Group Ⅱ, while the Pittsburgh Sleep Quality Index scores, Oswestry Disability Index scores, and incidence of adverse reactions in Treatment Group Ⅲ were significantly lower than in the other groups(P < 0.05). CONCLUSION:The external application of warm meridian medicated wine and polarized light therapy combined with acupuncture significantly reduces postoperative pain following vertebroplasty, enhances lumbar function, and improves both sleep quality and overall quality of life for patients. This approach is recommended for clinical application. 展开更多
关键词 PAIN postoperative VERTEBROPLASTY acupuncture polarized light therapy external application of warm meridian medicated wine
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Effects of Duhuo Jisheng Decoction Combined with Warm Acupuncture and Moxibustion on ODI Index and Lumbar Activity of Patients with Lumbar Disc Herniation
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作者 Shugang Peng Youling Huang +3 位作者 Yuan Liu Guosheng Ding Yafei Chen Haiting Ding 《Journal of Clinical and Nursing Research》 2025年第3期126-132,共7页
Objective:To explore the effect of combining Duhuo Jisheng decoction with warm acupuncture and moxibustion in the treatment of patients with lumbar disc herniation.Methods:Using a random number table method,a total of... Objective:To explore the effect of combining Duhuo Jisheng decoction with warm acupuncture and moxibustion in the treatment of patients with lumbar disc herniation.Methods:Using a random number table method,a total of 100 patients with lumbar disc herniation treated at Xianning Matang Hospital of Traditional Chinese Medicine from January 2021 to December 2023 were divided into a control group of 50 patients treated with Duhuo Jisheng decoction and a study group of 50 patients treated with Duhuo Jisheng decoction combined with warm acupuncture and moxibustion.The TCM syndrome scores,lumbar function,lumbar pain,and lumbar activity were compared between the two groups.Results:After intervention,the TCM syndrome scores,ODI,and VAS scores of both groups showed a decreasing trend compared to before intervention,and the decreasing trend was more significant in the study group(P<0.05).After intervention,the JOA and lumbar activity indicators of both groups showed an increasing trend compared to before intervention,and the increasing trend was more significant in the study group(P<0.05).Conclusion:Duhuo Jisheng decoction combined with warm acupuncture and moxibustion is an effective and safe treatment method for lumbar disc herniation,which can improve lumbar function and activity. 展开更多
关键词 Lumbar disc herniation Lumbar function warm acupuncture and moxibustion Lumbar activity Duhuo Jisheng decoction
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