In response to the actual demands of the energy storage type organic Rankine power generation cycle,this study proposes a new type of jacketed shell and tube heat exchanger with integrated cold storage and heat exchan...In response to the actual demands of the energy storage type organic Rankine power generation cycle,this study proposes a new type of jacketed shell and tube heat exchanger with integrated cold storage and heat exchange.N-tedecane is selected as the phase change material for cold storage,low-temperature water as the cold source,and R134a as the heat source.The phase change material for cold storage is filled inside the jacket tube of the heat exchanger.Cold fluid is introduced into the inner tube to cause the phase change material to condense and store cold.After the cold storage is completed,R134a flows in from the shell side and condenses through heat exchange with the solidified phase change material for energy storage.This study discusses the influence laws of different cold water mass flow rates and temperatures on the cold storage performance of this heat exchanger,and analyzes the condensation effect of R134a.The results show that when the mass flow rate is 0.5 kg/s and the cold water temperature is between 3 and 4℃,the average power of the energy storage heat exchanger in the condensation experiment is 80W,and the average convective heat transfer coefficient is 110.73 W/(m^(2)⋅K).This research provides an experimental basis for the development of energy storage organic Rankine power generation cycles.展开更多
A clear goal in cold tumor research is to identify strategies for converting them into immunologically‘hot’tumors with enhanced immune cell infiltration and activity,thereby improving their responsiveness to immunot...A clear goal in cold tumor research is to identify strategies for converting them into immunologically‘hot’tumors with enhanced immune cell infiltration and activity,thereby improving their responsiveness to immunotherapy.The genesis of cold tumors is exceedingly intricate.In recent times,as the analysis of this phenomenon has been pursued with greater depth,a suite of advanced diagnostic and therapeutic technologies has surfaced.These novel approaches and tactics are anticipated to modulate the tumor immune microenvironment across various dimensions,thereby facilitating the advancement of personalized and precise treatment modalities for cold tumors.The present article addresses the challenge of diminished therapeutic responsiveness to“cold tumors”within clinical settings.It systematically elucidates the multi-faceted regulatory mechanisms underlying immune evasion in cold tumors and offers a detailed analysis of advanced therapeutic strategies that incorporate nanotechnology,gene editing,and artificial intelligence methodologies.Furthermore,the future development trends of immunotherapy were explored in greater depth.It was posited that the convergence of artificial intelligence,multidimensional genomics,and emerging biotechnologies has presented positive prospects for the treatment of cold tumors,and has offered a theoretical foundation and technical framework for the transformation of cold tumors into“hot tumors”.展开更多
The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfa...The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfaces.A quantitative statistical experimental method was adopted to study the surface⁃contact transmission of micro⁃organisms,wherein the transfer rate of surface contact was the dependent variable and Escherichia coli was used as the indicator bacterium.The effects of contact pressure(0.44,0.86,1.55,2.25,and 2.94 N/cm^(2)),contact time(0,15,30,45,and 60 s),contact angle(15°and 25°),and surface materials(rubber and cotton gloves)were measured at two storage temperatures:cold storage(5℃)and freezing(-18℃).The results showed that as temperature decreases,the transfer of micro⁃organisms through surface contact becomes less probable.The contact time did not significantly influence the transfer rate of micro⁃organisms when items were handled at cold⁃storage temperatures.Based on these results,we recommend placing items as flat as possible to minimize the tilt angle when handling them at cold⁃storage temperatures.Additionally,if the tilt angle cannot be avoided,rubber gloves should be used when handling items stored at large tilt angles,whereas cotton gloves may be used for items placed at smaller angles.展开更多
As a large family of RNA helicases,DEAD-box(DDX)RNA helicases play crucial roles in almost all cellular RNA processing activities.However,the role of the DDX gene family in cold tolerance of mei(Prunus mume)remains un...As a large family of RNA helicases,DEAD-box(DDX)RNA helicases play crucial roles in almost all cellular RNA processing activities.However,the role of the DDX gene family in cold tolerance of mei(Prunus mume)remains unclear.In this study,we identified 45 DDX genes through whole-genome analysis unevenly distributed across eight chromosomes and scaffolds of mei.Based on the phylogenetic tree and gene structure analysis,the DDX genes were classified into nine subfamilies based on their motif compositions and intron-exon structures.The results of synteny analysis showed that segmental duplication was considered a major factor contributing to the amplification of the PmDDX family.RNA-Seq and qRT-PCR results revealed differential expression of PmDDX genes under cold stress.Among these,PmDDX39 was significantly up-regulated under cold stress,suggesting its positive role in modulating mei cold tolerance.We found that silenced PmDDX39 under cold stress led to greater damage than the wild seedlings via virus-induced gene silencing(VIGS).Conversely,overexpression of PmDDX39 in Arabidopsis enhanced cold stress tolerance.Moreover,dual luciferase and yeast one-hybrid(Y1H)demonstrated that PmDDX39 directly activates the expression of the C-repeat binding factor(PmCBFf)by binding to its promoters.This study provides new insights into the structure,evolution,and functional role of the PmDDX gene family in mei responses to cold stress.展开更多
This study presents the first systematic investigation of the rock geochemistry,hydrogeochemistry,geochronology,and formation mechanisms of the calcareous travertine-type cold volcano at Muji,Xinjiang.The Muji cold vo...This study presents the first systematic investigation of the rock geochemistry,hydrogeochemistry,geochronology,and formation mechanisms of the calcareous travertine-type cold volcano at Muji,Xinjiang.The Muji cold volcano is composed predominantly of travertine,which exhibited light rare earth element enrichment relative to heavy rare earth elements.The δ^(13)C values range from 7.1‰ to 11.1‰,while δ^(18)O values span from -12.3‰ to -7.8‰,classifying it as hypogean travertine.CO_(2) primarily originates from carbonate rock decarbonation,with a portion derived from the mantle.Water samples collected from the crater show HCO 3-Ca and HCO 3-Ca·Mg hydrochemistry types.U-Th dating of calcite indicates the Muji cold volcano formed between approximately 6.3 and 2.7 ka BP.The morphology and distribution pattern of the cold volcanoes are primarily controlled by hydrostatic pressure and the southwest boundary fault of the Muji Basin.Hydrostatic pressure of groundwater determines the growth height of the cones.The bead-like distribution orientation of the volcanic cones and the major axis direction of the elliptical contour lines of the cones align with the strike of the southwest boundary fault of the Muji Basin,indicating significant control by this fault.展开更多
Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis t...Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis to examine the grain size characteristics of major riparian dunes in the typical cold and arid deserts of China.The results indicate that major riparian dunes of deserts in study area can be classified into three types based on their grain size characteristics.The Bartlett test of sphericity and the Kaiser-Meyer-Olkin(KMO)test were also performed,and their significance values were found to be 0.000 and 0.584,respectively.The results of the principal component analysis revealed that the cumulative contribution rate of the total variance reached 85.9%for the two principal components with characteristic roots greater than 1.0.The primary principal component included medium sand,whereas the secondary principal component included fine sand.We conducted a cluster analysis and classified the samples into three major types.Type I rivers include the Keriya River,Langqu River,Tora River and Heihe River,which are characterized by by fine particle size,and well-sorted.Type II includes Mu Bulag River,Kuye River,and the Xar Moron River,Compared with type I,it has a relatively coarser mean grain size and relatively poor sorting for this type.Type III includes the Maquan River,which is characterized mainly by fine sand and medium sand,accounting for more than 90%,and the sorting coefficient(0.52)suggests relatively well sorting in this pattern.Moreover,principal component analysis was applied to determine the particle sizes of samples from different watersheds.Moreover,these sediments exhibit both hydromorphic and aeolian features.At the drainage basin scale,the mode and intensity of aeolian-fluvial interactions depend on climatic conditions.In arid and semi-arid climate regions,wind is the dominant force,and the grain size exhibits significant aeolian features.Conversely,in the semi-humid region,flowing water is the dominant force,and riparian dunes in this region are formed by aeolian-fluvial interaction.The angle between the wind direction and flow direction in different reaches influences both the supply of sediment sources and the development of riparian dunes.This study will provide a new perspective for evaluating aeolian-fluvial interactions on riparian dunes in the deserts of China’s cold and arid regions.展开更多
In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road perfor...In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road performance of emulsified asphalt cold recycled mixtures(ECRM),this study employed recycled asphalt pavement(RAP)and reclaimed inorganic binder stabilized aggregate(RAI)as dual recycled materials for ECRM preparation.The blending ratios of reclaimed base and surface layer mixtures significantly influence ECRM's performance,with adjusted proportions substantially improving compressive strength and dynamic modulus.Firstly,three distinct proportioning options were developed for the recycled materials.Mix designs incorporating varying RAP/RAI ratios were used to determine the optimal mix parameters:moisture content,cement dosage,and emulsified asphalt content.Subsequently,comprehensive performance evaluations were conducted through high-temperature wheel tracking tests,freeze-thaw splitting tests,uniaxial compression tests,and dynamic modulus measurements to analyze the pavement characteristics of the three ECRM formulations.Experimental results demonstrate:Compared with ECRM with a blending ratio of RAP:RAI:new aggregate=30:50:20(Option 1),the dynamic stability,freeze-thaw splitting strength ratio,compressive strength,and compressive resilient modulus of ECRM under Option 3(RAP:RAI:new aggregate=50:30:20)decreased by 31.8%,5.2%,16.4%,and 13.1%,respectively.This indicates that increasing RAP content while reducing RAI proportion enhances the tensile strength of ECRM,yet adversely affects its high-temperature stability,moisture resistance,and compressive performance.This work not only addresses the challenge of jointly utilizing asphalt pavement waste and base waste,but also provides a cost-effective and sustainable method for the stable application of milling material resources in road engineering.展开更多
The evolution of the S'precipitate in Al−Cu−Mg alloy was investigated using transmission electron microscopy(TEM),high-angle annular dark-field scanning transmission electron microscopy(HAADF−STEM),molecular dynam...The evolution of the S'precipitate in Al−Cu−Mg alloy was investigated using transmission electron microscopy(TEM),high-angle annular dark-field scanning transmission electron microscopy(HAADF−STEM),molecular dynamics(MD)simulations,and other analytical techniques.The precipitation behavior during different aging stages of the supersaturated solid solution formed after rapid cold punching was focused,which induces rapid dissolution of precipitates.The findings reveal that the precipitation sequence is significantly influenced by aging temperature.At higher aging temperatures,which mitigate lattice distortion in the matrix,the precipitation sequence follows the conventional path.Conversely,at lower aging temperatures,where lattice distortion persists,the sequence deviates,suppressing the formation of Guinier−Preston−Bagaryatsky(GPB)zones.MD simulations confirm that the variations in solute atom diffusion rates at different aging temperatures lead to the differences in the S'phase precipitation sequence.展开更多
Objective:To evaluate the clinical efficacy of umbilical herbal application combined with pestle needle therapy in the treatment of functional diarrhea(FD)due to deficient cold of the spleen and stomach.Methods:A tota...Objective:To evaluate the clinical efficacy of umbilical herbal application combined with pestle needle therapy in the treatment of functional diarrhea(FD)due to deficient cold of the spleen and stomach.Methods:A total of 72 patients with FD were enrolled and randomly assigned to two groups using the random number table method,with 36 patients in each group.Both groups received conventional Western medication treatment.The observation group additionally received umbilical application of Wen Yang Bu Pi Gao(Yang-warming and spleenstrengthening herbal paste)combined with pestle needle therapy.After 7 d of treatment,the clinical efficacy was assessed.Traditional Chinese medicine(TCM)symptom scores,irritable bowel syndrome-quality of life(IBS-QOL)score,and the incidence of adverse reactions were compared between the two groups.Results:The total effective rate in the observation group was 91.7%,which was significantly higher than 69.4%in the control group(P<0.05).After treatment,TCM symptom and IBS-QOL scores in both groups were significantly reduced compared to those before treatment(P<0.05),and the scores in the observation group were significantly lower than those in the control group(P<0.05).No adverse reactions occurred in either group during the treatment period.Conclusion:Compared to conventional Western medication treatment alone,the addition of umbilical application of Wen Yang Bu Pi Gao combined with pestle needle therapy can more effectively alleviate clinical symptoms and improve the quality of life in patients with FD due to deficient cold of the spleen and stomach.展开更多
Phase Change Material(PCM)-based cold energy storage system(CESS)can effectively utilize the peak and valley power resources to reduce the excessive dependence on the power grid.In this study,a PCM-based CESS was desi...Phase Change Material(PCM)-based cold energy storage system(CESS)can effectively utilize the peak and valley power resources to reduce the excessive dependence on the power grid.In this study,a PCM-based CESS was designed for cold storage applications.The optimal number of PCM plates was determined through numerical simulations to meet the required cold storage temperature and control time.Additionally,the air temperature field,flow field,and melting characteristics of the PCMplates during the cooling release process were analyzed.The effects of plate positioning and thickness on the cooling release performance were further investigated.The results indicated that when 64PCMplateswere used,the duration formaintaining temperatures below−18℃increased from0.6 h to approximately 16.94 h.During the cooling release process,the temperature field in the cold storage exhibited stratification,and the melting of the PCM plates was non-uniform.Placing the PCM plates at the top or within the interlayers without cargo above proved more effective,with their cooling release power being approximately twice that of the PCM plates placed in the interlayers with cargo above.Furthermore,reducing the thickness of the PCMplates from15 to 7.5mmresulted in a 3.6-h increase in the time below−18℃and a 4.5-h reduction in the time required to reach 80%liquid phase fraction.展开更多
1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-...1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-sized particles(5-50μm)to fabricate coatings[1-3].CS has been extensively used in a variety of coating applications,such as aerospace,automotive,energy,medical,marine,and others,to provide protection against high temperatures,corrosion,erosion,oxidation,and chemicals[4,5].Nowadays,the technical interest in CS is twofold:(i)as a repair process for damaged components,and(ii)as a solid-state additive manufacturing process.Compared to other fusion-based additive manufacturing(AM)technologies,Cold Spray Additive Manufacturing(CSAM)is a new member of the AM family that can enable the fabrication of deposits without undergoing melting.The chemical composition has been largely preserved from the powder to the deposit due to the minimal oxidation.The significant advantages of CSAM over other additive manufacturing processes include a high production rate,unlimited deposition size,high flexibility,and suitability for repairing damaged parts.展开更多
Challenges arise in global viticulture due to low temperatures.To ensure the sustainable and high-quality development of the wine industry,it is essential to breed wine grape varieties that are not only of high qualit...Challenges arise in global viticulture due to low temperatures.To ensure the sustainable and high-quality development of the wine industry,it is essential to breed wine grape varieties that are not only of high quality but also possess cold hardiness.Intraspecific recurrent selection in Vitis vinifera can enhance cold hardiness while maintaining fruit quality.In this study,we used‘Ecolly’as an intermediary grape variety for crossing with‘Cabernet Sauvignon’,‘Marselan’,and‘Dunkelfelder’,including three reciprocal crosses and a total of 1,657 intraspecific hybrids.We characterized the cold hardiness of these intraspecific hybrids and analyzed the genetic aspects of cold hardiness,ultimately identifying excellent strains with cold hardiness.Parameters like mean high-temperature exotherm(mHTE),mean low-temperature exotherm(mLTE),bound/free water ratio,water loss ratio in vitro,frost damage grades,and overall performance displayed partially normal distributions.In intraspecific hybrids,there was a maternal advantage in traits related to bound/free water ratio and water loss ratio.Some hybrid populations exhibited values for mHTE,mLTE,and water loss ratio that were lower than the low parent's values,while bound/free water ratio showed values higher than the high parent's values.Among the 1,657 intraspecific hybrids,52 strains could bud under stress at-18℃,and seven of these strains excelled in three important cold hardiness measures.Our study revealed that cold hardiness in V.vinifera is influenced by multiple genes and is a quantitative trait.Intraspecific hybridization can produce a small number of superior strains with enhanced cold hardiness.展开更多
BACKGROUND Cold exposure has traditionally been considered a pathological factor that can easily impair gastrointestinal(GI)digestion.Shihosogan-tang(ST),Yijung-tang(YT),and Pyeongwi-san(PS)are well-known herbal formu...BACKGROUND Cold exposure has traditionally been considered a pathological factor that can easily impair gastrointestinal(GI)digestion.Shihosogan-tang(ST),Yijung-tang(YT),and Pyeongwi-san(PS)are well-known herbal formulas frequently used to treat GI disorders in East Asia.AIM To compare the effects of these herbal formulas on GI motility and investigate their mechanisms of action using a cold stress(CS)-induced dyspepsia mouse model.METHODS C57BL/6J mice were exposed to CS by immersion in cold water(10±1℃)while being restrained in conical tubes for 1 hour.This procedure was repeated six times over 2 weeks.Herbal formulas or mosapride(positive control)were administered orally five times per week over a 2-week period.RESULTS The pre-test results revealed that CS,rather than restraint stress,significantly delayed gut motility in mice.However,PS and ST notably improved gastric emptying and intestinal transit,surpassing YT.Additionally,PS and ST significantly reduced gastric potential of hydrogen and increased pepsin and lipase gene expression compared to CS.The observed mechanisms likely involved increased gastric acidity and enhanced levels of digestive enzymes,such as pepsin and lipase.Furthermore,PS administration elevated GI hormone levels and metabolites related to the gut microbiota(5-hydroxytryptamine and short-chain fatty acid)more effectively than ST and YT treatments.CONCLUSION PS more effectively alleviated CS-induced GI dysfunction than both YT and ST.These comparative findings offer valuable insights for clinical applications in the treatment of cold-related digestive disorders.展开更多
Although magnesium-aluminum alloys,such as AZ80 and AZ91 have promising application potential in automotive,high-speed train and aerospace fields,their age-hardening response is generally not very appreciable.In this ...Although magnesium-aluminum alloys,such as AZ80 and AZ91 have promising application potential in automotive,high-speed train and aerospace fields,their age-hardening response is generally not very appreciable.In this work,the aging-hardening response of AZ80 alloy was effectively enhanced by applying cold-rolling deformation before conducting conventional aging treatment at 200°C.Compared to the directly aged sample,the yield strength of the pre-rolling and aged sample was increased by 35 MPa.Electron microscope examination confirmed that profuse{10¯11}and{10¯11}-{10¯12}twins,consisting of high density of dislocations and stacking faults,were generated by cold rolling.Blocky or ellipsoidal Mg_(17)Al_(12)precipitates formed at the twin boundaries(TBs)during subsequent aging treatment.Crystallographic analysis indicated that the precipitates at{10¯11}TBs always held an identical Potter OR with both the matrix and twin,while the precipitates at{10¯11}-{10¯12}TBs exhibited three different ORs:Burgers OR,Potter OR and P-S OR with either the matrix or the twin.Moreover,recrystallized grains were found inside{10¯11}-{10¯12}double twins after peak-aging at 200°C,implying that precipitation and recrystallization might occur concurrently along TBs at a relatively low temperature.It was speculated that the highly stored energy inside twins and the high elastic energy between the precipitates and twins were driving factors for the occurrence of recrystallization.展开更多
Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties...Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were investigated.The results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer period.The microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine grains.During layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg matrix.The mechanical properties of the CA-WAAM deposited sample showed isotropic characteristics.The ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,respectively.The microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6.展开更多
Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous ...Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous quantitative analyses often simplified the chorus dispersion relation by using the cold plasma assumption.However,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic disturbances.We here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to 2018.The statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma density.The region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density decreases.In addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus waves.Compared with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those below.Furthermore,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.展开更多
Additive manufacturing (AM) of high-strength metallic alloys frequently encounters detrimental distortion and cracking, attributed to the accumulation of thermal stresses. These issues significantly impede the practic...Additive manufacturing (AM) of high-strength metallic alloys frequently encounters detrimental distortion and cracking, attributed to the accumulation of thermal stresses. These issues significantly impede the practical application of as-printed components. This study examines the Mg-15Gd-1Zn-0.4Zr (GZ151K, wt.%) alloy, a prototypical high-strength casting Mg-RE alloy, fabricated through laser powder bed fusion (LPBF). Despite achieving ultra-high strength, the GZ151K alloy concurrently exhibits a pronounced cold-cracking susceptibility. The as-printed GZ151K alloy consists of almost fully fine equiaxed grains with an average grain size of merely 2.87 µm. Subsequent direct aging (T5) heat treatment induces the formation of dense prismatic β' precipitates. Consequently, the LPBF-T5 GZ151K alloy manifests an ultra-high yield strength of 405 MPa, surpassing all previously reported yield strengths for Mg alloys fabricated via LPBF and even exceeding that of its extrusion-T5 counterpart. Interestingly, as-printed GZ151K samples with a build height of 2 mm exhibit no cracking, whereas samples with build heights ranging from 4 to 18 mm demonstrate severe cold cracking. Thermal stress simulation also suggests that the cold cracking susceptibility increases significantly with increasing build height. The combination of high thermal stress and low ductility in the as-printed GZ151K alloy culminates in a high cold cracking susceptibility. This study offers novel insights into the intricate issue of cold cracking in the LPBF process of high-strength Mg alloys, highlighting the critical balance between achieving high strength and mitigating cold cracking susceptibility.展开更多
The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to bio...The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to biotic and abiotic stresses.However,the mechanism underlying the response of this module to cold stress and its role in flower development in wintersweet(Chimonanthus praecox)remains unclear.Through expression pattern analysis,calcium ion(Ca^(2+))concentration assays,correlation analysis,and linear regression analysis,we found that the[Ca^(2+)],along with CpCBL8 and CpCIPK9 expression levels in wintersweet flower buds(FBs),significantly decreased during the initial flowering stage when the chilling requirement reached 570 chill units(CU).Notably,there was a significant positive correlation between[Ca^(2+)]and CpCBL8 expression.Ca^(2+)increased the expression of Cp CBL8 and CpCIPK9 in FBs,causing a significant delay in the flowering of wintersweet.Furthermore,the function of CpCBL8 was studied using heterologous transformation.Overexpression of CpCBL8 significantly delayed flowering time and significantly reduced cold tolerance and altered the expression pattern of endogenous genes related to low-temperature stress and flower development in transgenic Arabidopsis thaliana.Additionally,transcriptome analysis of chilling-induced dormancy breaking and flower bud enlargement revealed that CpCBL8 and CpCIPK9 were negatively regulated by cold,and the expression pattern of endogenous genes related to flower development and cold stress in wintersweet were similar to that of in A.thaliana.Moreover,protein-protein interaction(PPI)analysis revealed that CpCBL8 and CpCIPK9 interacted in the plasma membrane and nucleus.On the basis of these findings,we speculated that the CpCBL8-CpCIPK9 module plays a crucial role in regulating responses to cold stress and flower development in wintersweet.This study elucidated molecular mechanisms through which the downregulation of the Ca^(2+)-induced CpCBL8-CpCIPK9 module results in dormancy breaking and enhances cold tolerance.This study provides valuable insights for the cultivation of new varieties of wintersweet with increased ornamental value and enhanced cold stress tolerance.展开更多
A recent discovery in rice has revealed an elegant trick of nature:crops can teach their later generations to survive the cold through inherited memories written in chemical marks on the DNA letters,representing the f...A recent discovery in rice has revealed an elegant trick of nature:crops can teach their later generations to survive the cold through inherited memories written in chemical marks on the DNA letters,representing the first clear demonstration of what scientists call the“inheritance of acquired characteristics”-a phenomenon that biologists have debated for over two centuries.展开更多
基金the the basic scientific research Funds project of Heilongjiang Universities[grant numbers 2024-KYYWF-0554].
文摘In response to the actual demands of the energy storage type organic Rankine power generation cycle,this study proposes a new type of jacketed shell and tube heat exchanger with integrated cold storage and heat exchange.N-tedecane is selected as the phase change material for cold storage,low-temperature water as the cold source,and R134a as the heat source.The phase change material for cold storage is filled inside the jacket tube of the heat exchanger.Cold fluid is introduced into the inner tube to cause the phase change material to condense and store cold.After the cold storage is completed,R134a flows in from the shell side and condenses through heat exchange with the solidified phase change material for energy storage.This study discusses the influence laws of different cold water mass flow rates and temperatures on the cold storage performance of this heat exchanger,and analyzes the condensation effect of R134a.The results show that when the mass flow rate is 0.5 kg/s and the cold water temperature is between 3 and 4℃,the average power of the energy storage heat exchanger in the condensation experiment is 80W,and the average convective heat transfer coefficient is 110.73 W/(m^(2)⋅K).This research provides an experimental basis for the development of energy storage organic Rankine power generation cycles.
文摘A clear goal in cold tumor research is to identify strategies for converting them into immunologically‘hot’tumors with enhanced immune cell infiltration and activity,thereby improving their responsiveness to immunotherapy.The genesis of cold tumors is exceedingly intricate.In recent times,as the analysis of this phenomenon has been pursued with greater depth,a suite of advanced diagnostic and therapeutic technologies has surfaced.These novel approaches and tactics are anticipated to modulate the tumor immune microenvironment across various dimensions,thereby facilitating the advancement of personalized and precise treatment modalities for cold tumors.The present article addresses the challenge of diminished therapeutic responsiveness to“cold tumors”within clinical settings.It systematically elucidates the multi-faceted regulatory mechanisms underlying immune evasion in cold tumors and offers a detailed analysis of advanced therapeutic strategies that incorporate nanotechnology,gene editing,and artificial intelligence methodologies.Furthermore,the future development trends of immunotherapy were explored in greater depth.It was posited that the convergence of artificial intelligence,multidimensional genomics,and emerging biotechnologies has presented positive prospects for the treatment of cold tumors,and has offered a theoretical foundation and technical framework for the transformation of cold tumors into“hot tumors”.
基金National Natural Science Foundation of China(Grant No.52278121).
文摘The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfaces.A quantitative statistical experimental method was adopted to study the surface⁃contact transmission of micro⁃organisms,wherein the transfer rate of surface contact was the dependent variable and Escherichia coli was used as the indicator bacterium.The effects of contact pressure(0.44,0.86,1.55,2.25,and 2.94 N/cm^(2)),contact time(0,15,30,45,and 60 s),contact angle(15°and 25°),and surface materials(rubber and cotton gloves)were measured at two storage temperatures:cold storage(5℃)and freezing(-18℃).The results showed that as temperature decreases,the transfer of micro⁃organisms through surface contact becomes less probable.The contact time did not significantly influence the transfer rate of micro⁃organisms when items were handled at cold⁃storage temperatures.Based on these results,we recommend placing items as flat as possible to minimize the tilt angle when handling them at cold⁃storage temperatures.Additionally,if the tilt angle cannot be avoided,rubber gloves should be used when handling items stored at large tilt angles,whereas cotton gloves may be used for items placed at smaller angles.
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.QNTD202503)Forestry and Grassland Science and Technology Innovation Youth Top Talent Project of China(Grant No.2020132608)Beijing High-Precision Discipline Project,Discipline of Ecological Environment of Urban and Rural Human Settlements.
文摘As a large family of RNA helicases,DEAD-box(DDX)RNA helicases play crucial roles in almost all cellular RNA processing activities.However,the role of the DDX gene family in cold tolerance of mei(Prunus mume)remains unclear.In this study,we identified 45 DDX genes through whole-genome analysis unevenly distributed across eight chromosomes and scaffolds of mei.Based on the phylogenetic tree and gene structure analysis,the DDX genes were classified into nine subfamilies based on their motif compositions and intron-exon structures.The results of synteny analysis showed that segmental duplication was considered a major factor contributing to the amplification of the PmDDX family.RNA-Seq and qRT-PCR results revealed differential expression of PmDDX genes under cold stress.Among these,PmDDX39 was significantly up-regulated under cold stress,suggesting its positive role in modulating mei cold tolerance.We found that silenced PmDDX39 under cold stress led to greater damage than the wild seedlings via virus-induced gene silencing(VIGS).Conversely,overexpression of PmDDX39 in Arabidopsis enhanced cold stress tolerance.Moreover,dual luciferase and yeast one-hybrid(Y1H)demonstrated that PmDDX39 directly activates the expression of the C-repeat binding factor(PmCBFf)by binding to its promoters.This study provides new insights into the structure,evolution,and functional role of the PmDDX gene family in mei responses to cold stress.
基金supported by the National Natural Science Foundation of China(Grant No.42272349).
文摘This study presents the first systematic investigation of the rock geochemistry,hydrogeochemistry,geochronology,and formation mechanisms of the calcareous travertine-type cold volcano at Muji,Xinjiang.The Muji cold volcano is composed predominantly of travertine,which exhibited light rare earth element enrichment relative to heavy rare earth elements.The δ^(13)C values range from 7.1‰ to 11.1‰,while δ^(18)O values span from -12.3‰ to -7.8‰,classifying it as hypogean travertine.CO_(2) primarily originates from carbonate rock decarbonation,with a portion derived from the mantle.Water samples collected from the crater show HCO 3-Ca and HCO 3-Ca·Mg hydrochemistry types.U-Th dating of calcite indicates the Muji cold volcano formed between approximately 6.3 and 2.7 ka BP.The morphology and distribution pattern of the cold volcanoes are primarily controlled by hydrostatic pressure and the southwest boundary fault of the Muji Basin.Hydrostatic pressure of groundwater determines the growth height of the cones.The bead-like distribution orientation of the volcanic cones and the major axis direction of the elliptical contour lines of the cones align with the strike of the southwest boundary fault of the Muji Basin,indicating significant control by this fault.
基金Under the auspices of the General Project of Science and Technology Department of Shaanxi Province(No.2023-JCYB-264)General Program of National Natural Science Foundation of China(No.41801004,42371008,42471012)。
文摘Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis to examine the grain size characteristics of major riparian dunes in the typical cold and arid deserts of China.The results indicate that major riparian dunes of deserts in study area can be classified into three types based on their grain size characteristics.The Bartlett test of sphericity and the Kaiser-Meyer-Olkin(KMO)test were also performed,and their significance values were found to be 0.000 and 0.584,respectively.The results of the principal component analysis revealed that the cumulative contribution rate of the total variance reached 85.9%for the two principal components with characteristic roots greater than 1.0.The primary principal component included medium sand,whereas the secondary principal component included fine sand.We conducted a cluster analysis and classified the samples into three major types.Type I rivers include the Keriya River,Langqu River,Tora River and Heihe River,which are characterized by by fine particle size,and well-sorted.Type II includes Mu Bulag River,Kuye River,and the Xar Moron River,Compared with type I,it has a relatively coarser mean grain size and relatively poor sorting for this type.Type III includes the Maquan River,which is characterized mainly by fine sand and medium sand,accounting for more than 90%,and the sorting coefficient(0.52)suggests relatively well sorting in this pattern.Moreover,principal component analysis was applied to determine the particle sizes of samples from different watersheds.Moreover,these sediments exhibit both hydromorphic and aeolian features.At the drainage basin scale,the mode and intensity of aeolian-fluvial interactions depend on climatic conditions.In arid and semi-arid climate regions,wind is the dominant force,and the grain size exhibits significant aeolian features.Conversely,in the semi-humid region,flowing water is the dominant force,and riparian dunes in this region are formed by aeolian-fluvial interaction.The angle between the wind direction and flow direction in different reaches influences both the supply of sediment sources and the development of riparian dunes.This study will provide a new perspective for evaluating aeolian-fluvial interactions on riparian dunes in the deserts of China’s cold and arid regions.
基金sponsored by National Natural Science Foundation of China(No.52308466)SASAC Science and Technology Innovation Project(JF-23-01-0063)Shaanxi Provincial Transportation Research Project(25-84 K,25-85 K).
文摘In recent years,the amount of waste generated during milling has increased dramatically,and improper disposal poses a significant environmental challenge.To mitigate environmental pollution and enhance the road performance of emulsified asphalt cold recycled mixtures(ECRM),this study employed recycled asphalt pavement(RAP)and reclaimed inorganic binder stabilized aggregate(RAI)as dual recycled materials for ECRM preparation.The blending ratios of reclaimed base and surface layer mixtures significantly influence ECRM's performance,with adjusted proportions substantially improving compressive strength and dynamic modulus.Firstly,three distinct proportioning options were developed for the recycled materials.Mix designs incorporating varying RAP/RAI ratios were used to determine the optimal mix parameters:moisture content,cement dosage,and emulsified asphalt content.Subsequently,comprehensive performance evaluations were conducted through high-temperature wheel tracking tests,freeze-thaw splitting tests,uniaxial compression tests,and dynamic modulus measurements to analyze the pavement characteristics of the three ECRM formulations.Experimental results demonstrate:Compared with ECRM with a blending ratio of RAP:RAI:new aggregate=30:50:20(Option 1),the dynamic stability,freeze-thaw splitting strength ratio,compressive strength,and compressive resilient modulus of ECRM under Option 3(RAP:RAI:new aggregate=50:30:20)decreased by 31.8%,5.2%,16.4%,and 13.1%,respectively.This indicates that increasing RAP content while reducing RAI proportion enhances the tensile strength of ECRM,yet adversely affects its high-temperature stability,moisture resistance,and compressive performance.This work not only addresses the challenge of jointly utilizing asphalt pavement waste and base waste,but also provides a cost-effective and sustainable method for the stable application of milling material resources in road engineering.
基金supported by the China Scholarship Council (CSC) Local Cooperation Program (No. 202308430176)the National Natural Science Foundation of China (No. 52271177)the Hunan Provincial Natural Science Foundation Regional Joint Fund, China (No. 2023JJ50173)。
文摘The evolution of the S'precipitate in Al−Cu−Mg alloy was investigated using transmission electron microscopy(TEM),high-angle annular dark-field scanning transmission electron microscopy(HAADF−STEM),molecular dynamics(MD)simulations,and other analytical techniques.The precipitation behavior during different aging stages of the supersaturated solid solution formed after rapid cold punching was focused,which induces rapid dissolution of precipitates.The findings reveal that the precipitation sequence is significantly influenced by aging temperature.At higher aging temperatures,which mitigate lattice distortion in the matrix,the precipitation sequence follows the conventional path.Conversely,at lower aging temperatures,where lattice distortion persists,the sequence deviates,suppressing the formation of Guinier−Preston−Bagaryatsky(GPB)zones.MD simulations confirm that the variations in solute atom diffusion rates at different aging temperatures lead to the differences in the S'phase precipitation sequence.
基金supported by 2023 Annual Public Welfare Technological Application Research Project of Jinhua City(2023年度金华市公益性技术应用研究项目,No.2023-4-256).
文摘Objective:To evaluate the clinical efficacy of umbilical herbal application combined with pestle needle therapy in the treatment of functional diarrhea(FD)due to deficient cold of the spleen and stomach.Methods:A total of 72 patients with FD were enrolled and randomly assigned to two groups using the random number table method,with 36 patients in each group.Both groups received conventional Western medication treatment.The observation group additionally received umbilical application of Wen Yang Bu Pi Gao(Yang-warming and spleenstrengthening herbal paste)combined with pestle needle therapy.After 7 d of treatment,the clinical efficacy was assessed.Traditional Chinese medicine(TCM)symptom scores,irritable bowel syndrome-quality of life(IBS-QOL)score,and the incidence of adverse reactions were compared between the two groups.Results:The total effective rate in the observation group was 91.7%,which was significantly higher than 69.4%in the control group(P<0.05).After treatment,TCM symptom and IBS-QOL scores in both groups were significantly reduced compared to those before treatment(P<0.05),and the scores in the observation group were significantly lower than those in the control group(P<0.05).No adverse reactions occurred in either group during the treatment period.Conclusion:Compared to conventional Western medication treatment alone,the addition of umbilical application of Wen Yang Bu Pi Gao combined with pestle needle therapy can more effectively alleviate clinical symptoms and improve the quality of life in patients with FD due to deficient cold of the spleen and stomach.
基金supported by National Natural Science Foundation of China(Nos.51806092,52201410)Non-Carbon Energy Conversion and Utilization Institute under the Shanghai Class IV Peak Disciplinary Development Program,High-End Foreign Experts Recruitment Plan of China(G2022013028L).
文摘Phase Change Material(PCM)-based cold energy storage system(CESS)can effectively utilize the peak and valley power resources to reduce the excessive dependence on the power grid.In this study,a PCM-based CESS was designed for cold storage applications.The optimal number of PCM plates was determined through numerical simulations to meet the required cold storage temperature and control time.Additionally,the air temperature field,flow field,and melting characteristics of the PCMplates during the cooling release process were analyzed.The effects of plate positioning and thickness on the cooling release performance were further investigated.The results indicated that when 64PCMplateswere used,the duration formaintaining temperatures below−18℃increased from0.6 h to approximately 16.94 h.During the cooling release process,the temperature field in the cold storage exhibited stratification,and the melting of the PCM plates was non-uniform.Placing the PCM plates at the top or within the interlayers without cargo above proved more effective,with their cooling release power being approximately twice that of the PCM plates placed in the interlayers with cargo above.Furthermore,reducing the thickness of the PCMplates from15 to 7.5mmresulted in a 3.6-h increase in the time below−18℃and a 4.5-h reduction in the time required to reach 80%liquid phase fraction.
基金supported by the National Natural Science Foundation of China(No.52061135101 and 52001078)the German Research Foundation(DFG,No.448318292)+3 种基金the Technology Innovation Guidance Special Foundation of Shaanxi Province(No.2023GXLH-085)the Fundamental Research Funds for the Central Universities(No.D5000240161)the Project of Key areas of innovation team in Shaanxi Province(No.2024RS-CXTD-20)The author Yingchun Xie thanks the support from the National Key R&D Program(No.2023YFE0108000).
文摘1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-sized particles(5-50μm)to fabricate coatings[1-3].CS has been extensively used in a variety of coating applications,such as aerospace,automotive,energy,medical,marine,and others,to provide protection against high temperatures,corrosion,erosion,oxidation,and chemicals[4,5].Nowadays,the technical interest in CS is twofold:(i)as a repair process for damaged components,and(ii)as a solid-state additive manufacturing process.Compared to other fusion-based additive manufacturing(AM)technologies,Cold Spray Additive Manufacturing(CSAM)is a new member of the AM family that can enable the fabrication of deposits without undergoing melting.The chemical composition has been largely preserved from the powder to the deposit due to the minimal oxidation.The significant advantages of CSAM over other additive manufacturing processes include a high production rate,unlimited deposition size,high flexibility,and suitability for repairing damaged parts.
基金supported by Project of Ningxia Hui Autonomous Region Key R&D Program(Grant No.NXNYYZ202101)the National Natural Science Foundation of China(Grant No.32360804)+1 种基金Ningxia Science and Technology Department major scientific and technological achievements transformation project(Grant No.2022CJE9007)Ningxia Natural Science Foundation(Grant No.2023AAC03064).
文摘Challenges arise in global viticulture due to low temperatures.To ensure the sustainable and high-quality development of the wine industry,it is essential to breed wine grape varieties that are not only of high quality but also possess cold hardiness.Intraspecific recurrent selection in Vitis vinifera can enhance cold hardiness while maintaining fruit quality.In this study,we used‘Ecolly’as an intermediary grape variety for crossing with‘Cabernet Sauvignon’,‘Marselan’,and‘Dunkelfelder’,including three reciprocal crosses and a total of 1,657 intraspecific hybrids.We characterized the cold hardiness of these intraspecific hybrids and analyzed the genetic aspects of cold hardiness,ultimately identifying excellent strains with cold hardiness.Parameters like mean high-temperature exotherm(mHTE),mean low-temperature exotherm(mLTE),bound/free water ratio,water loss ratio in vitro,frost damage grades,and overall performance displayed partially normal distributions.In intraspecific hybrids,there was a maternal advantage in traits related to bound/free water ratio and water loss ratio.Some hybrid populations exhibited values for mHTE,mLTE,and water loss ratio that were lower than the low parent's values,while bound/free water ratio showed values higher than the high parent's values.Among the 1,657 intraspecific hybrids,52 strains could bud under stress at-18℃,and seven of these strains excelled in three important cold hardiness measures.Our study revealed that cold hardiness in V.vinifera is influenced by multiple genes and is a quantitative trait.Intraspecific hybridization can produce a small number of superior strains with enhanced cold hardiness.
基金Supported by the National Research Foundation of Korea,No.2022M3A9E4017033。
文摘BACKGROUND Cold exposure has traditionally been considered a pathological factor that can easily impair gastrointestinal(GI)digestion.Shihosogan-tang(ST),Yijung-tang(YT),and Pyeongwi-san(PS)are well-known herbal formulas frequently used to treat GI disorders in East Asia.AIM To compare the effects of these herbal formulas on GI motility and investigate their mechanisms of action using a cold stress(CS)-induced dyspepsia mouse model.METHODS C57BL/6J mice were exposed to CS by immersion in cold water(10±1℃)while being restrained in conical tubes for 1 hour.This procedure was repeated six times over 2 weeks.Herbal formulas or mosapride(positive control)were administered orally five times per week over a 2-week period.RESULTS The pre-test results revealed that CS,rather than restraint stress,significantly delayed gut motility in mice.However,PS and ST notably improved gastric emptying and intestinal transit,surpassing YT.Additionally,PS and ST significantly reduced gastric potential of hydrogen and increased pepsin and lipase gene expression compared to CS.The observed mechanisms likely involved increased gastric acidity and enhanced levels of digestive enzymes,such as pepsin and lipase.Furthermore,PS administration elevated GI hormone levels and metabolites related to the gut microbiota(5-hydroxytryptamine and short-chain fatty acid)more effectively than ST and YT treatments.CONCLUSION PS more effectively alleviated CS-induced GI dysfunction than both YT and ST.These comparative findings offer valuable insights for clinical applications in the treatment of cold-related digestive disorders.
基金financially supported by the National Natural Science Foundation of China(No.52071040 and 51871036)Natural Science Foundation of Shandong Province,China(No.ZR2022QE008)China Postdoctoral Science Foundation(No.2022M712984)。
文摘Although magnesium-aluminum alloys,such as AZ80 and AZ91 have promising application potential in automotive,high-speed train and aerospace fields,their age-hardening response is generally not very appreciable.In this work,the aging-hardening response of AZ80 alloy was effectively enhanced by applying cold-rolling deformation before conducting conventional aging treatment at 200°C.Compared to the directly aged sample,the yield strength of the pre-rolling and aged sample was increased by 35 MPa.Electron microscope examination confirmed that profuse{10¯11}and{10¯11}-{10¯12}twins,consisting of high density of dislocations and stacking faults,were generated by cold rolling.Blocky or ellipsoidal Mg_(17)Al_(12)precipitates formed at the twin boundaries(TBs)during subsequent aging treatment.Crystallographic analysis indicated that the precipitates at{10¯11}TBs always held an identical Potter OR with both the matrix and twin,while the precipitates at{10¯11}-{10¯12}TBs exhibited three different ORs:Burgers OR,Potter OR and P-S OR with either the matrix or the twin.Moreover,recrystallized grains were found inside{10¯11}-{10¯12}double twins after peak-aging at 200°C,implying that precipitation and recrystallization might occur concurrently along TBs at a relatively low temperature.It was speculated that the highly stored energy inside twins and the high elastic energy between the precipitates and twins were driving factors for the occurrence of recrystallization.
基金supported by the National Natural Science Foundation of China(No.51805265)the Fundamental Research Funds for the Central Universities,China(No.30922010921).
文摘Thin walls of an AZ91 magnesium alloy with fine equiaxed grains were fabricated via cold arc-based wire arc additive manufacturing(CA-WAAM),and the droplet transfer behaviours,microstructures,and mechanical properties were investigated.The results showed that the cold arc process reduced splashing at the moment of liquid bridge breakage and effectively shortened the droplet transfer period.The microstructures of the deposited samples exhibited layered characteristics with alternating distributions of coarse and fine grains.During layer-by-layer deposition,the β-phase precipitated and grew preferentially along grain boundaries,while the fineη-Al_(8)Mn_(5)phase was dispersed in the α-Mg matrix.The mechanical properties of the CA-WAAM deposited sample showed isotropic characteristics.The ultimate tensile strength and elongation in the building direction(BD)were 282.7 MPa and 14.2%,respectively.The microhardness values of the deposited parts were relatively uniform,with an average value of HV 69.6.
基金supported by the National Natural Science Foundation of China (NSFC) through Grant Number 42074193
文摘Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous quantitative analyses often simplified the chorus dispersion relation by using the cold plasma assumption.However,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic disturbances.We here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to 2018.The statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma density.The region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density decreases.In addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus waves.Compared with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those below.Furthermore,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.
基金supported by the National Key Research and Development Program of China(No.2021YFB3701000)the National Natural Science Foundation of China(Nos.51971130,52201129,U21A2047,51821001,U2037601)+2 种基金support by the China Postdoctoral Science Foun-dation(2023M742219)the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20240419support by the Ministry of Education,Singapore,under its Academic Research Fund Tier 2(MOE-T2EP50221-0013).
文摘Additive manufacturing (AM) of high-strength metallic alloys frequently encounters detrimental distortion and cracking, attributed to the accumulation of thermal stresses. These issues significantly impede the practical application of as-printed components. This study examines the Mg-15Gd-1Zn-0.4Zr (GZ151K, wt.%) alloy, a prototypical high-strength casting Mg-RE alloy, fabricated through laser powder bed fusion (LPBF). Despite achieving ultra-high strength, the GZ151K alloy concurrently exhibits a pronounced cold-cracking susceptibility. The as-printed GZ151K alloy consists of almost fully fine equiaxed grains with an average grain size of merely 2.87 µm. Subsequent direct aging (T5) heat treatment induces the formation of dense prismatic β' precipitates. Consequently, the LPBF-T5 GZ151K alloy manifests an ultra-high yield strength of 405 MPa, surpassing all previously reported yield strengths for Mg alloys fabricated via LPBF and even exceeding that of its extrusion-T5 counterpart. Interestingly, as-printed GZ151K samples with a build height of 2 mm exhibit no cracking, whereas samples with build heights ranging from 4 to 18 mm demonstrate severe cold cracking. Thermal stress simulation also suggests that the cold cracking susceptibility increases significantly with increasing build height. The combination of high thermal stress and low ductility in the as-printed GZ151K alloy culminates in a high cold cracking susceptibility. This study offers novel insights into the intricate issue of cold cracking in the LPBF process of high-strength Mg alloys, highlighting the critical balance between achieving high strength and mitigating cold cracking susceptibility.
基金funded by the Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0236)Fundamental Research Funds for the Central Universities(SWU-XDJH202308)Earmarked Funds for the China Agriculture Research System(CARS-26)。
文摘The complex of calcineurin B-like protein(CBL)and CBL-interacting protein kinase(CIPK)serves as key components in calcium-sensing,orchestrating various signals crucial for plant growth,development,and responses to biotic and abiotic stresses.However,the mechanism underlying the response of this module to cold stress and its role in flower development in wintersweet(Chimonanthus praecox)remains unclear.Through expression pattern analysis,calcium ion(Ca^(2+))concentration assays,correlation analysis,and linear regression analysis,we found that the[Ca^(2+)],along with CpCBL8 and CpCIPK9 expression levels in wintersweet flower buds(FBs),significantly decreased during the initial flowering stage when the chilling requirement reached 570 chill units(CU).Notably,there was a significant positive correlation between[Ca^(2+)]and CpCBL8 expression.Ca^(2+)increased the expression of Cp CBL8 and CpCIPK9 in FBs,causing a significant delay in the flowering of wintersweet.Furthermore,the function of CpCBL8 was studied using heterologous transformation.Overexpression of CpCBL8 significantly delayed flowering time and significantly reduced cold tolerance and altered the expression pattern of endogenous genes related to low-temperature stress and flower development in transgenic Arabidopsis thaliana.Additionally,transcriptome analysis of chilling-induced dormancy breaking and flower bud enlargement revealed that CpCBL8 and CpCIPK9 were negatively regulated by cold,and the expression pattern of endogenous genes related to flower development and cold stress in wintersweet were similar to that of in A.thaliana.Moreover,protein-protein interaction(PPI)analysis revealed that CpCBL8 and CpCIPK9 interacted in the plasma membrane and nucleus.On the basis of these findings,we speculated that the CpCBL8-CpCIPK9 module plays a crucial role in regulating responses to cold stress and flower development in wintersweet.This study elucidated molecular mechanisms through which the downregulation of the Ca^(2+)-induced CpCBL8-CpCIPK9 module results in dormancy breaking and enhances cold tolerance.This study provides valuable insights for the cultivation of new varieties of wintersweet with increased ornamental value and enhanced cold stress tolerance.
文摘A recent discovery in rice has revealed an elegant trick of nature:crops can teach their later generations to survive the cold through inherited memories written in chemical marks on the DNA letters,representing the first clear demonstration of what scientists call the“inheritance of acquired characteristics”-a phenomenon that biologists have debated for over two centuries.
