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
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
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
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
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
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
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
BACKGROUND This study seeks to systematically assess the effects of warm acupuncture combined with acupoint massage on the recovery of gastrointestinal function following gastric cancer surgery.AIM To evaluate the imp...BACKGROUND This study seeks to systematically assess the effects of warm acupuncture combined with acupoint massage on the recovery of gastrointestinal function following gastric cancer surgery.AIM To evaluate the impact of warm acupuncture combined with acupoint massage on postoperative gastrointestinal function recovery after gastric cancer surgery,based on a systematic review and meta-analysis.METHODS A comprehensive search was conducted across multiple databases,including PubMed,Cochrane Library,EMBASE,Web of Science,CNKI,Wanfang,and VIP,for relevant studies published up to January 2025.Meta-analyses were carried out using RevMan 5.4,with results presented as standardized mean difference(SMD)or odds ratio with 95%confidence interval(CI).Study heterogeneity was evaluated using the I2 statistic,and sensitivity analyses were performed to assess the stability of the findings.RESULTS A total of 8 randomized controlled trials involving 694 patients were included.The meta-analysis showed that warm acupuncture combined with acupoint massage significantly improved postoperative gastrointestinal function by reducing the time to first flatus(SMD=-2.14,95%CI:-3.14 to-1.14,P<0.0001),time to first bowel movement(SMD=-2.43,95%CI:-3.52 to-1.34,P<0.0001),time to bowel sounds recovery(SMD=-3.15,95%CI:-4.50 to-1.80,P<0.00001),and time to initiate nasogastric or jejunal feeding(SMD=-1.31,95%CI:-2.44 to-0.18,P=0.02).CONCLUSION The combination of warm acupuncture and acupoint massage markedly enhances gastrointestinal recovery following surgery.展开更多
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
Objective:Although there is evidence to support the therapeutic effect of acupuncture on allergic rhinitis(AR),it is not clear whether acupuncture can achieve an efficacy comparable to that of pharmacological therapy....Objective:Although there is evidence to support the therapeutic effect of acupuncture on allergic rhinitis(AR),it is not clear whether acupuncture can achieve an efficacy comparable to that of pharmacological therapy.This multicenter,non-inferiority,single-blinded randomized controlled trial aimed to compare the differences in efficacy between warm needling(WN)therapy and loratadine(LO)in improving AR symptoms and quality of life.Methods:A total of 98 patients with persistent AR(PAR)were randomly divided into two groups in a 1:1 ratio:treatment group receiving WN therapy at Dazhui(GV14)and normal acupuncture at other acupoints for 12 sessions in 4 weeks and control group receiving LO at a dosage of 10 mg/day for oral administration.The study duration was 28 weeks(4-week treatment period with a 24-week follow-up).The primary outcome was the mean change in the Total Nasal Symptom Score(TNSS)from baseline to week 28,and the secondary outcomes included the Total Non-Nasal Symptom Score(TNNSS)and the Rhinoconjunctivitis Quality of Life Questionnaire(RQLQ)score.Statistical analyses were conducted us-ing SPSS22.0.Both intention-to-treat and treatment compliance analyses were performed to analyze all outcomes.Results:After intervention,TNSS scores improved from baseline to week 28 by 5.18(95%confidence interval[CI]:3.91,6.45;P<0.001)in the WN group and 4.59(95%CI 3.28,5.89;P<0.001)in the LO group,but the changes did not differ between the groups(P=0.515).The margin by 95%CI(−1.20,2.38)was not reached,indicating non-inferiority.WN therapy resulted in clinical improvements in TNNSS,with a significant difference com pared with LO treatment(f=5.466,P=0.021).WN therapy also resulted in clinical improvements in RQLQ scores,with a significant difference compared with LO(f=9.222,P=0.003).Conclusions:WN therapy demonstrated comparable efficacy to oral LO in improving nasal symptoms of PAR.However,it showed superior effects in alleviating concomitant nasal symptoms and enhancing patients’quality of life.展开更多
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
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
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
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
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
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
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
The recovery of motor function in spastic hemiplegia following stroke is closely associated with cortical reorganisation.This study aimed to investigate the effects of warm acupuncture combined with rehabilitation tra...The recovery of motor function in spastic hemiplegia following stroke is closely associated with cortical reorganisation.This study aimed to investigate the effects of warm acupuncture combined with rehabilitation training on cortical activity and upper limb function using functional near-infrared spectroscopy.Ninety patients were randomly assigned to a warm acupuncture group,a rehabilitation training group,or a combined intervention group.After four weeks of intervention,clinical scores and changes in oxyhaemoglobin concentration in the affected motor cortex were assessed.Results demonstrated that the combined intervention group showed significantly greater improvement in Fugl-Meyer scores,reduced muscle tone,and enhanced activation in the affected primary motor cortex compared to the single intervention groups.Furthermore,functional improvement was significantly correlated with cortical activation changes.These findings indicate a synergistic effect between warm acupuncture and rehabilitation training,potentially mediated through promoting functional reorganisation of the affected cerebral cortex.This provides neuroimaging evidence supporting integrated Chinese and Western medicine rehabilitation protocols.展开更多
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
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
基金supported by the Natural Science Fund of China(31771724)the Key Research and Development Project of Shaanxi Province(2024NC-ZDCYL-01-10).
文摘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.
基金Natural science foundation of Inner Mongolia(2024LHMS06018)The basic scientific research funding for directly affiliated universities in the Inner Mongolia(JY20250094)。
文摘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.
文摘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.
基金funded by the Swiss National Science Foundation(SNF 200020_182084).
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(No.42072211)the National Natural Science Foundation of China(No.42401048)the Third Xinjiang Scientific Expedition and Research Program(No.2021xjkk0302)。
文摘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”.
基金jointly supported by the National Natural Science Foundation of China(Grant Nos.42422502,42275038)the China Meteorological Administration Climate Change Special Program(Grant No.QBZ202306)。
文摘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.
文摘BACKGROUND This study seeks to systematically assess the effects of warm acupuncture combined with acupoint massage on the recovery of gastrointestinal function following gastric cancer surgery.AIM To evaluate the impact of warm acupuncture combined with acupoint massage on postoperative gastrointestinal function recovery after gastric cancer surgery,based on a systematic review and meta-analysis.METHODS A comprehensive search was conducted across multiple databases,including PubMed,Cochrane Library,EMBASE,Web of Science,CNKI,Wanfang,and VIP,for relevant studies published up to January 2025.Meta-analyses were carried out using RevMan 5.4,with results presented as standardized mean difference(SMD)or odds ratio with 95%confidence interval(CI).Study heterogeneity was evaluated using the I2 statistic,and sensitivity analyses were performed to assess the stability of the findings.RESULTS A total of 8 randomized controlled trials involving 694 patients were included.The meta-analysis showed that warm acupuncture combined with acupoint massage significantly improved postoperative gastrointestinal function by reducing the time to first flatus(SMD=-2.14,95%CI:-3.14 to-1.14,P<0.0001),time to first bowel movement(SMD=-2.43,95%CI:-3.52 to-1.34,P<0.0001),time to bowel sounds recovery(SMD=-3.15,95%CI:-4.50 to-1.80,P<0.00001),and time to initiate nasogastric or jejunal feeding(SMD=-1.31,95%CI:-2.44 to-0.18,P=0.02).CONCLUSION The combination of warm acupuncture and acupoint massage markedly enhances gastrointestinal recovery following surgery.
基金supported by the National Key Research and Development Program of China(2023YFC3007703)National Natural Science Foundation of China(Grant Nos.41675066,42394122)+1 种基金CAS Project of Stable Support for Youth Team in Basic Research Field(YSRR-018)the Chinese Meridian Project。
文摘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.
基金Supported by Beijing Municipal Science&Technology Commission Program:Z151100004015117Shenzhen Science and Technology Plan Project:JCYJ20210324120804012Shenzhen Luohu District Soft Science Research Plan project:LX202202128。
文摘Objective:Although there is evidence to support the therapeutic effect of acupuncture on allergic rhinitis(AR),it is not clear whether acupuncture can achieve an efficacy comparable to that of pharmacological therapy.This multicenter,non-inferiority,single-blinded randomized controlled trial aimed to compare the differences in efficacy between warm needling(WN)therapy and loratadine(LO)in improving AR symptoms and quality of life.Methods:A total of 98 patients with persistent AR(PAR)were randomly divided into two groups in a 1:1 ratio:treatment group receiving WN therapy at Dazhui(GV14)and normal acupuncture at other acupoints for 12 sessions in 4 weeks and control group receiving LO at a dosage of 10 mg/day for oral administration.The study duration was 28 weeks(4-week treatment period with a 24-week follow-up).The primary outcome was the mean change in the Total Nasal Symptom Score(TNSS)from baseline to week 28,and the secondary outcomes included the Total Non-Nasal Symptom Score(TNNSS)and the Rhinoconjunctivitis Quality of Life Questionnaire(RQLQ)score.Statistical analyses were conducted us-ing SPSS22.0.Both intention-to-treat and treatment compliance analyses were performed to analyze all outcomes.Results:After intervention,TNSS scores improved from baseline to week 28 by 5.18(95%confidence interval[CI]:3.91,6.45;P<0.001)in the WN group and 4.59(95%CI 3.28,5.89;P<0.001)in the LO group,but the changes did not differ between the groups(P=0.515).The margin by 95%CI(−1.20,2.38)was not reached,indicating non-inferiority.WN therapy resulted in clinical improvements in TNNSS,with a significant difference com pared with LO treatment(f=5.466,P=0.021).WN therapy also resulted in clinical improvements in RQLQ scores,with a significant difference compared with LO(f=9.222,P=0.003).Conclusions:WN therapy demonstrated comparable efficacy to oral LO in improving nasal symptoms of PAR.However,it showed superior effects in alleviating concomitant nasal symptoms and enhancing patients’quality of life.
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.42107476 and 42177421)the China Postdoctoral International Exchange Fellowship Program(No.PC2021099)+1 种基金the Science and Technology Innovation Program of Hunan Province(No.2020RC2058)the China Scholarship Council(CSC,No.202206600004,to D.Yuan).
文摘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.
基金supported by the National Natural Science Foundation of China(No.52071212).
文摘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%.
基金financially supported by the National Natural Science Foundation of China[grant number 42088101]。
文摘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.
基金supported by the National Natural Science Foundation of China[grant number 42088101]the National Key Research and Development Program of China[grant number 2022YFF0801702]。
文摘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.
基金supported by the National Natural Science Foundation of China (Grant Nos.32330067,31971419,32311530110,and 32171486)。
文摘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.
基金the financial support from the funding of the National Natural Science Foundation of China(NSFC)(Grant Nos.42401160 and U22A20596)the Science and Technology Plan Project of Linzhi(Grant No.SYQ2024-13).
文摘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.
基金Jining Key R&D Program:Near-Infrared Brain Imaging Study on the Efficacy of Warm Acupuncture Combined with Rehabilitation Training for Spastic Hemiplegia(Project No.:2024YXNS237)Shandong Provincial Traditional Chinese Medicine Science and Technology Project:Project No.M-2023263,Title:Clinical Efficacy and Mechanism of Dual-Point Electroacupuncture Stimulating Bilateral Neiguan Acupoints for Awakening in Severe Craniocerebral Injury Patients Based on Near-Infrared Brain Imaging Technology.
文摘The recovery of motor function in spastic hemiplegia following stroke is closely associated with cortical reorganisation.This study aimed to investigate the effects of warm acupuncture combined with rehabilitation training on cortical activity and upper limb function using functional near-infrared spectroscopy.Ninety patients were randomly assigned to a warm acupuncture group,a rehabilitation training group,or a combined intervention group.After four weeks of intervention,clinical scores and changes in oxyhaemoglobin concentration in the affected motor cortex were assessed.Results demonstrated that the combined intervention group showed significantly greater improvement in Fugl-Meyer scores,reduced muscle tone,and enhanced activation in the affected primary motor cortex compared to the single intervention groups.Furthermore,functional improvement was significantly correlated with cortical activation changes.These findings indicate a synergistic effect between warm acupuncture and rehabilitation training,potentially mediated through promoting functional reorganisation of the affected cerebral cortex.This provides neuroimaging evidence supporting integrated Chinese and Western medicine rehabilitation protocols.
基金supported by the Key Project of Chinese Academy of Engineering(No.2019-XZ-11)the General Project of Chinese Academy of Engineering(No.2023-XY-18)+1 种基金the Open Fund of National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials of China(No.HKDNM201907)the Independent Project of State Key Laboratory of Powder Metallurgy,China。
文摘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.
基金supported by Excellent Research Group Program for Tibetan Plateau Earth System(continuation grant NSFC project No.41988101)the National Natural Science Foundation of China(Nos.U1803341 and 32061123008)+1 种基金the National Key R&D Program of China(No.2018YFA0606401)the National Youth Talent Support Program.
文摘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.
