Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological c...Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological conditions.In this study,we conducted experiments using four different sowing dates,the conventional sowing date 1(CS1),CS2(10 d later than CS1),DS1(30 d later than CS1),and DS2(30 d later than CS2),and three rice varieties,i.e.,Yixiangyou 2115,Fyou 498,and Chuanyou 6203.This experiment was conducted at four sites in the Sichuan Basin in 2018 and 2019 to evaluate the infuence of DS on the pasting properties of rice,which are a proxy for the eating and cooking quality(ECQ).In DS1 and DS2,the rice had a signifcantly greater amylose content(AC)but a lower protein content(PC),peak viscosity(PKV),cool paste viscosity(CPV),and hot paste viscosity(HPV)than in CS1 and CS2.Moreover,except for CS2 and DS1 in 2018,DS1 and DS2 led to 2.15-11.19%reductions in breakdown viscosity(BDV)and 23.46-108.47%increases in setback viscosity(SBV).However,the infuence of DS on rice pasting properties varied by study site and rice variety.In 2019,DS1 and DS2 led to BDV reductions of 2.35-9.33,2.61-8.61,10.03-17.78,and 2.06-8.93%,and SBV increases of 2.32-60.93,63.74-144.24,55.46-91.63,and-8.28-65.37%at the Dayi,Anzhou,Nanbu,and Shehong(except for SBV in CS2 and DS1)sites,respectively.DS resulted in greater reductions in PKV,HPV,CPV,and BDV and greater increases in the AC and SBV for Yixiangyou 2115 than for Chuanyou 6203 and Fyou 498.The correlation analysis indicated that PKV and HPV were signifcantly and positively related to the mean,maximum,and minimum temperatures after heading.These temperatures must be greater than 25.9,31.2,and 22.3℃,respectively,to increase the relative BDV and reduce the relative SBV of rice,thereby enhancing ECQ.In conclusion,DS might contribute to a signifcant deterioration in ECQ in machine-transplanted rice in the Sichuan Basin.A mean temperature above 25.9℃ after heading is required to improve the ECQ of rice.展开更多
The Sichuan Basin(SCB),China has a high incidence of extremely persistent heavy rainfall(EPHR)events.The EPHR events from 2009 to 2019 in the SCB were mainly concentrated over the northern and northwestern windward sl...The Sichuan Basin(SCB),China has a high incidence of extremely persistent heavy rainfall(EPHR)events.The EPHR events from 2009 to 2019 in the SCB were mainly concentrated over the northern and northwestern windward slopes and the central basin.They occurred from June to September,but especially in July,and peaked at 0300 LST.ERA5 reanalysis data and objective classification were used to investigate the synoptic patterns and their effects.There were three synoptic patterns during EPHR events,all accompanied by a Southwest Vortex.The location and intensity of the Southwest Vortex,thermal forcing of the Tibetan Plateau(TP),and low-level winds can greatly affect the intensity and spatial distribution of EPHR.When the Southwest Vortex was located in the western SCB and there were southerly low-level jets(LLJs),convergence and upslope wind would lead to EPHR over the northwestern or northern windward slopes.If there was no LLJ and the whole SCB was under the center of the Southwest Vortex,nocturnal EPHR was controlled by the internal circulation of the Southwest Vortex and the updraft generated by the thermal forcing of the TP,and the rainfall was weaker.The southeastern entrance of the SCB was a key area where the low-level wind dominated the nocturnal peak of EPHR.The nocturnal strengthened southeasterly wind in the key area is attributable to inertial oscillation,and the topographic friction plays an essential role in transporting momentum and moisture into the basin by generating easterly and northeasterly ageostrophic winds.展开更多
It is still a challenge to develop hierarchically nanostructured catalysts with simple approaches to enhance the low-temperature catalytic activity.Herein,a set of mesoporous Co-Cu binary metal oxides with different m...It is still a challenge to develop hierarchically nanostructured catalysts with simple approaches to enhance the low-temperature catalytic activity.Herein,a set of mesoporous Co-Cu binary metal oxides with different morphologies were successfully prepared via a facile ammonium bicarbonate precipitation method without any templates or surfactants,which were further applied for catalytic removal of carcinogenic toluene.Among the catalysts with different ratios,the CoCu_(0.2)composite oxide presented the best performance,where the temperature required for 90%conversion of toluene was only 237°C at the high weight hour space velocity(WHSV)of 240,000 mL/(gcat·hr).Meanwhile,compared to the related Co-Cu composite oxides prepared by using different precipitants(NaOH and H_(2)C_(2)O_(4)),the NH_(4)HCO_(3)-derived CoCu_(0.2)sample exhibited better catalytic efficiency in toluene oxidation,while the T90 were 22 and 28°C lower than those samples prepared by NaOH andH_(2)C_(2)O_(4)routes,respectively.Based on various characterizations,it could be deduced that the excellent performance was related to the small crystal size(6.7 nm),large specific surface area(77.0 m2/g),hollow hierarchical nanostructure with abundant high valence Co ions and adsorbed oxygen species.In situ DRIFTS further revealed that the possible reaction pathway for the toluene oxidation over CoCu_(0.2)catalyst followed the route of absorbed toluene→benzyl alcohol→benzaldehyde→benzoic acid→carbonate→CO_(2)and H_(2)O.In addition,CoCu_(0.2)sample could keep stable with long-time operation and occur little inactivation under humid condition(5 vol.%water),which revealed that the NH_(4)HCO_(3)-derived CoCu_(0.2)nanocatalyst possessed great potential in industrial applications for VOCs abatement.展开更多
A halophilic bacterium,named Halomonas sp.NEC-1 was isolated from the Nyer Co Salt Lake on the Xizang Plateau,SW China.The strain exhibited a broad pH tolerance range of 5-11,distinguishing it from Halomonas alkaliphi...A halophilic bacterium,named Halomonas sp.NEC-1 was isolated from the Nyer Co Salt Lake on the Xizang Plateau,SW China.The strain exhibited a broad pH tolerance range of 5-11,distinguishing it from Halomonas alkaliphila despite a 99% genetic similarity.Optimal growth conditions,determined through orthogonal experiments,were found to be 37℃,100-g/L salinity,and an initial pH of 6,resulting in a maximum OD_(600) of 7.98±0.06.Halomonas sp.NEC-1 produced 545.43±25.10 mg/L of ectoine under optimal conditions of 75-g/L salinity,40-g/L sodium glutamate,and an initial pH of 6.This production increased to 1388.81±3.69 mg/L after five rounds of hypo-osmotic shocks.During the shocks,ectoine productivity remained stable at approximately 16.29±0.04 to 17.28±0.48 mg/(L·h),representing a 43.40%-52.11% increase compared to the rate without any shock(11.36±1.05 mg/(L·h)).Additionally,the expression of the ectABC gene cluster,related to ectoine synthesis,significantly increased following the shocks,enhancing ectoine production.The ectoine extract demonstrated notable protective effects on Escherichia coli and plasmid DNA.After 10 min of exposure at 60℃,the colony count of E.coli treated with ectoine extract increased by 342% compared to treatment with distilled water.Furthermore,the ectoine extract protected plasmid DNA from 2,2′-Azobis(2-methylpropionamidine)dihydrochloride-induced damage.This study highlights Halomonas sp.NEC-1 is a promising strain for ectoine production and underscores the potential of microbial resources in salt lakes from Xizang region.展开更多
Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic ...Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.展开更多
短串联重复序列(short tandem repeat,STR)遗传标记在法庭科学DNA鉴定中占据绝对主导地位,包括中国在内的世界各国DNA数据库均基于STR遗传标记建立。STR遗传标记具有长度多态性和序列多态性。序列多态包括重复区和侧翼区序列的多态性。...短串联重复序列(short tandem repeat,STR)遗传标记在法庭科学DNA鉴定中占据绝对主导地位,包括中国在内的世界各国DNA数据库均基于STR遗传标记建立。STR遗传标记具有长度多态性和序列多态性。序列多态包括重复区和侧翼区序列的多态性。传统的基于毛细管电泳技术进行STR分型仅区分长度多态性,而深刻理解核心STR基因座的序列多态对于引物设计和DNA鉴定等方面至关重要。首先,STR扩增引物结合区的SNP、InDel可能干扰引物与DNA模板结合的亲和力,导致无法检测到某些等位基因或均衡性差,影响DNA鉴定准确性;其次,二代测序技术推动STR鉴定由长度多态分型向序列多态分型发展,显著提升了可检测的核心STR基因座多态信息含量,提高了其个体识别和亲缘关系分析效能;再者,不同人群具有不同的STR序列特征。近10年来,基于二代测序的STR序列多态性的研究逐渐增多,多个人群的序列多态性数据已经被报道,但以往的研究群体及数据较为零散,重复序列的数据格式不统一,导致核心STR基因座的序列多态性缺乏来自大数据的系统性总结和梳理。充分掌握核心STR基因座的序列特征对微量检材的个体识别、混合样本拆分、亲子鉴定中突变来源的确定等具有十分重要的意义。本文以19个常染色体核心STR为分析对象,整合了目前文献报道的群体数据和公开数据库中的中国人群变异频率数据,系统综述了这些STR的序列多态性,包括归纳STR基因座重复区的变异类型和分析变异规律,总结了中国人群中STR侧翼区的高频变异,并探讨了在STR序列检验中可能遇到的难点,以期为STR序列的应用解析、案件检验中稀有等位基因的判别以及STR试剂盒的研制等方面提供参考。展开更多
Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which ...Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and exploitation.Both domestic and international natural gas hydrate production tests typically employ a single-well production model.Although this approach has seen some success,it continues to be hindered by low production rates and short production cycles.Therefore,there is an urgent need to explore a new well network to significantly increase the production of a single well.This paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field tests.It further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) replacement.On this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was proposed.The study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single well.Moreover,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate.展开更多
Chronic pain after spine surgery(CPSS)is a complex disorder characterized by multifactorial pathogenesis that occurs in 8%–40%of patients undergoing lumbar spine surgery.We aimed to develop a rat model that mimics cl...Chronic pain after spine surgery(CPSS)is a complex disorder characterized by multifactorial pathogenesis that occurs in 8%–40%of patients undergoing lumbar spine surgery.We aimed to develop a rat model that mimics clinical CPSS conditions by taking two sequential surgical procedures.Step 1:A plastic rod was inserted into the left L5 intervertebral foramen to produce a steady compression on the dorsal root ganglion(DRG)and the spinal nerve,a common cause of low back pain(LBP).Step 2:The rod was removed after 7 days when rats exhibited mechanical and heat hypersensitivity in the ipsilateral hindpaw,followed by a full L5 laminectomy to mimic spine decompression surgery in LBP patients.The retention of the rod induced a prolonged LBP-like behavior but was quickly resolved after rod removal without laminectomy.However,rats that received laminectomy after rod removal developed heightened mechanical and heat sensitivity in the hindpaw,impaired gait,and reduced spontaneous exploration activity,indicating CPSS.Patch clamp recording revealed a significant augmentation in the intrinsic excitability of smalldiameter DRG neurons in CPSS rats.Administration of Dermorphin[D-Arg2,Lys4](1–4)amide(DALDA,5mg/kg,i.p.),a peripherally acting mu-opioid receptor(MOR)-preferred agonist,attenuated pain hypersensitivity,capsaicin-induced[Ca^(2+)]i rising and the increased intrinsic excitability of DRG neurons from CPSS rats.Our findings suggest that this new model,which mirrors the nature of CPSS developed in patients,may be useful for future studies of the underlying mechanisms.展开更多
The Xing'an-Inner Mongolia Orogen is a critical tectonic unit for constraining the evolution of the Paleo-Asian Ocean.However,the location and time of the closure of the Paleo-Asian Ocean are still debated.Here,we...The Xing'an-Inner Mongolia Orogen is a critical tectonic unit for constraining the evolution of the Paleo-Asian Ocean.However,the location and time of the closure of the Paleo-Asian Ocean are still debated.Here,we select a representative basin in Dashizhai in northeastern China,using U-Pb zircon geochronology and geochemistry to analyze the sedimentary facies,depositional ages,and provenance.The results show that the ages of the Dashizhai Formation range from 400 to 347 Ma,the Shoushangou Formation range from 400 to 348 Ma,the Zhesi Formation range from 307 to 252 Ma,and the Linxi Formation range from 299 to 241 Ma.The Dashizhai Formation is composed of metamorphic andesite and clastic rocks.The Shoushangou Formation comprises siltstone,rhyolite,and argillaceous siltstone.The Zhesi and Linxi Formations are composed of mudstone and argillaceous siltstone.Geochemical data shows that these rocks are enriched in light rare earth elements and depleted in Eu with various La/Sc,Th/Sc,and La/Co ratios.The Permian Dashizhai Basin is from Permian volcanic and felsic igneous rocks from the Ergun,Xing'an,and Songliao blocks.The absence of the Late Carboniferous strata in the Dashizhai Basin indicates an extension setting during this period.Furthermore,we suggest the Xing'an-Inner Mongolia Orogen was an uplifting process associated with evolution the Paleo-Asian Ocean during the Late Permian.展开更多
Electrocatalysts are an effective strategy to mitigate the shuttling effect of lithium polysulfides(LiPSs)and accelerate the redox kinetics of LiPSs in lithium-sulfur(Li-S)batteries.However,traditional electrocatalyst...Electrocatalysts are an effective strategy to mitigate the shuttling effect of lithium polysulfides(LiPSs)and accelerate the redox kinetics of LiPSs in lithium-sulfur(Li-S)batteries.However,traditional electrocatalysts only have a single active site and often undergo structural collapse and aggregation during charging and discharging,resulting in reduced catalytic performance.Herein,the two-dimensional(2D)polar high-entropy La_(0.71)Sr_(0.29)Co_(0.21)Ni_(0.20)Fe_(0.19)Cr_(0.20)Cu_(0.20)O_(3)(LCO-HEO)nanosheets were rationally designed and successfully synthesized to address this issue.The distinct functional polar sites in LCOHEOs were formed by the d-d orbital hybridization between spatially coupling adjacent transition metals,which can strengthen the dipole-dipole interaction between polar LCO-HEOs and polar LiPSs.2D polar LCO-HEO nanosheets can efficiently capture and trigger the tandem catalysis of polar LiPSs during their sequential conversion.The S/LCO-HEO composite cathode exhibits a high specific capacity of 1161.1 mA h g^(-1)at 1.0 C,with an ultralow capacity attenuation rate of 0.036%per cycle over 1200 cycles,and achieves stable cycling for 1500 cycles even at 8.0 C.Furthermore,even with a high sulfur loading(5.5 mg cm^(-2))and a low electrolyte/sulfur(E/S)ratio(4.0μL mg^(-1)),the S/LCO-HEO composite cathode shows desirable sulfur utilization and good cycle stability.This work demonstrates the feasibility of high entropy-driven multiple distinct functional polar sites for high-rate and long-cycle Li-S batteries.展开更多
Benziodazole-triflate,as a novel heterocyclic hypervalent iodine(III)reagent,was prepared from the reaction of hypervalent chloroiodine(III)with silver triflate under mild conditions.The structure of this new reagent ...Benziodazole-triflate,as a novel heterocyclic hypervalent iodine(III)reagent,was prepared from the reaction of hypervalent chloroiodine(III)with silver triflate under mild conditions.The structure of this new reagent was elucidated by NMR spectroscopy and X-ray crystallography,and its reactions with diverseα-electron withdrawing group substituted carbonyl compounds were investigated.The results implied that benziodazole-triflate could be selectively used as both a 2-iodobenzamido-transfer reagent for the synthesis of oxazole compounds,and a triflate-transfer reagent for the triflation ofβ-keto-sulfones.Ionic mechanistic pathways,supported by density functional theory(DFT)calculations,were proposed to account for the divergent selectivities of the transformations.展开更多
Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitiga...Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitigate soil N losses,our understanding of its interaction with N fertilizer and its long-term effects remains limited owing to experimental constraints.In this study,two microcosm incubation experiments were performed to evaluate the effect of fresh biochar,compared to 8-year field-aged biochar application in a poplar plantation,on soil N_(2)O emissions triggered by biogas slurry application.The experiments incorporated three biochar levels and four biogas slurry application rates,each with three replicates.The results demonstrated that fresh and aged biochar significantly reduced soil cumulative N_(2)O emissions by 31%–61%and 75%–99%,respectively,over 7 d following biogas slurry application.However,these mitigating effects diminished over incubation time.The application of fresh biochar significantly reduced soil available organic carbon and potential denitrification rates,suggesting that it primarily suppressed soil N_(2)O emissions by limiting the supply of electron donors.In contrast,aged biochar had minimal impact on soil available organic carbon and generally enhanced the abundances of bacterial amoA,nirS,nirK,and nosZ genes.This suggests that the aged biochar potentially suppressed soil N_(2)O emissions by promoting complete denitrification.Partial least squares structure equation model(PLS-SEM)analysis corroborated the two different mechanisms regulating the inhibitory influence of fresh and aged biochar on soil N_(2)O emissions.The lower R^(2)of PLS-SEM analysis for aged biochar(R^(2)=0.256)compared to that for fresh biochar(R^(2)=0.798)indicates that other factors,such as biochar properties,potentially affect soil N_(2)O emissions and warrant further investigation.This study highlights the need to evaluate the long-term effect of biochar on soil N_(2)O emissions,owing to the dynamic changes in biochar and soil properties over time.展开更多
5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on re...5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on reproductive development in Artemia,a 5-HT type 7 receptor gene(5-HT_(7Ar))was identified in parthenogenetic Artemia and characterized.Sequence analysis revealed that the open reading frame of 5-HT_(7Ar) encodes a 414-aa protein.5-HT_(7Ar) showed higher expression in both brain and ovary at early embryo stage,5-HT_(7Ar) could be detected during ovarian development and the highest expression was observed at early embryo stage.Silencing of the 5-HT_(7Ar) in Artemia at early embryo stage decreased significantly the expression level of 5-HT_(7Ar) gene and protein at late oocyte,early embryo,and late embryo stage.Moreover,silencing of the 5-HT_(7Ar) resulted in a decreased fecundity,which corresponds to abnormal oocytes during the embryo development.Artemia tended to produce nauplii after the silencing of 5-HT_(7Ar),indicating that 5-HT_(7Ar) may also involve in the determination of its reproduction mode.The findings of this study provide an insight into the regulation of reproductive development in Artemia and the function of 5-HT_(7Ar).展开更多
Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical properties.As a result,surface chemistry research plays a crucial role in various fields such as catalysis,...Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical properties.As a result,surface chemistry research plays a crucial role in various fields such as catalysis,energy,materials,quantum,and microelectronics.Surface science mainly investigates the correspondence between surface property and functionality.Scanning probe microscopy(SPM)techniques are important tools to characterize surface properties because of the capability of atomic-scale imaging,spectroscopy and manipulation at the single-atom level.In this review,we summarize recent advances in surface electronic,magnetic and optical properties characterized mainly by SPM-based methods.We focus on elucidating theπ-magnetism in graphene-based nanostructures,construction of spin qubits on surfaces,topology properties of surface organic structures,STM-based light emission,tip-enhanced Raman spectroscopy and integration of machine learning in SPM studies.展开更多
Background:U2AF homology motif kinase 1(UHMK1)has been associated with RNA processing and protein phosphorylation,thereby influencing tumor progression.The study aimed to explore its regulatory mechanisms and biologic...Background:U2AF homology motif kinase 1(UHMK1)has been associated with RNA processing and protein phosphorylation,thereby influencing tumor progression.The study aimed to explore its regulatory mechanisms and biological functions in human prostate cancer(PCa).Methods:In this study,we systematically evaluated the expression and prognostic significance of UHMK1 in public databases,followed by validation through immunohis-tochemistry(IHC)in PCa specimens.Both gain-of-function and loss-of-function experiments were conducted to elucidate the role of UHMK1 in vitro and in vivo.Additionally,a series of molecular and biochemical assays were performed to investigate the regulatory mechanisms underlying UHMK1 activity.Results:Our findings revealed that UHMK1 expression was significantly upregulated in PCa tissues and correlated with poor patient prognosis,as demonstrated by analysis of public datasets and confirmed by immunohistochemical staining.Functional studies showed that UHMK1 depletion suppressed tumor cell proliferation and metastasis,while its overexpression promoted these processes.Mechanistically,we identified that UHMK1 phosphorylates nuclear receptor coactivator 3(NCOA3),which subsequently activates activating transcription factor 4(ATF4)to upregulate methylenetetrahydrofolate dehy-drogenase 2(MTHFD2)transcription.Interestingly,MTHFD2 was found to reciprocally enhance UHMK1 expression,establishing a positive feedback loop.Conclusions:In conclusion,our data suggest that the UHMK1-MTHFD2 axis forms a positive feedback loop that drives PCa progression.Targeting this loop represents a promising therapeutic strategy for restraining prostate cancer development and progression.展开更多
The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mechanical properties.In this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centri...The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mechanical properties.In this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced.This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings,employing both experimental approaches and ProCast simulation methodologies.The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains.Under the condition of pouring temperature of 1,600℃,rotation speed of 800 r·min^(-1) and pouring time of 6 s,the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa,and the tensile strength at 800℃ reaches 705 MPa,which is significantly higher than that of traditional as-cast Ti-Al alloy.展开更多
Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wa...Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wave energy storage but is also affected by the local available wave probability.Different distributions and trends between the available wave energy and total wave energy storage are observed.Larger values of total wave energy storage are concentrated in the high-latitude westerlies zone,whereas available wave energy storage exhibits greater concentration in the middle-low latitude regions.In each basin,there is a notable upward trend in both total wave energy storage and available wave energy storage.However,the northern Hemisphere(NH)exhibits an increasing trend in available wave probability,whereas the southern Hemisphere(SH)experiences a decreasing trend.This divergence contributes to the spatial distributions of available wave energy storage becoming increasingly uniform.These trends in wave energy are primarily influenced by changes in significant wave height.Although the increasing trend of significant wave height across all frequency ranges induces the growth of total wave energy storage,only the increasing of wave heights falling in 1.3−4 m can cause the growth of available wave energy storage.The consistent increasing rates of wave height under different mean levels contribute to the divergent trends in available wave probability.展开更多
基金supported by the National Natural Science Foundation of China(U20A2022 and 32372217)the National Key Research and Development Program of China(2022YFD2300700)the Free Exploration Program of State Key Laboratory of Crop Gene Exploration and Utilization in Sichuan Basin,China(SKL-ZY202216)。
文摘Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological conditions.In this study,we conducted experiments using four different sowing dates,the conventional sowing date 1(CS1),CS2(10 d later than CS1),DS1(30 d later than CS1),and DS2(30 d later than CS2),and three rice varieties,i.e.,Yixiangyou 2115,Fyou 498,and Chuanyou 6203.This experiment was conducted at four sites in the Sichuan Basin in 2018 and 2019 to evaluate the infuence of DS on the pasting properties of rice,which are a proxy for the eating and cooking quality(ECQ).In DS1 and DS2,the rice had a signifcantly greater amylose content(AC)but a lower protein content(PC),peak viscosity(PKV),cool paste viscosity(CPV),and hot paste viscosity(HPV)than in CS1 and CS2.Moreover,except for CS2 and DS1 in 2018,DS1 and DS2 led to 2.15-11.19%reductions in breakdown viscosity(BDV)and 23.46-108.47%increases in setback viscosity(SBV).However,the infuence of DS on rice pasting properties varied by study site and rice variety.In 2019,DS1 and DS2 led to BDV reductions of 2.35-9.33,2.61-8.61,10.03-17.78,and 2.06-8.93%,and SBV increases of 2.32-60.93,63.74-144.24,55.46-91.63,and-8.28-65.37%at the Dayi,Anzhou,Nanbu,and Shehong(except for SBV in CS2 and DS1)sites,respectively.DS resulted in greater reductions in PKV,HPV,CPV,and BDV and greater increases in the AC and SBV for Yixiangyou 2115 than for Chuanyou 6203 and Fyou 498.The correlation analysis indicated that PKV and HPV were signifcantly and positively related to the mean,maximum,and minimum temperatures after heading.These temperatures must be greater than 25.9,31.2,and 22.3℃,respectively,to increase the relative BDV and reduce the relative SBV of rice,thereby enhancing ECQ.In conclusion,DS might contribute to a signifcant deterioration in ECQ in machine-transplanted rice in the Sichuan Basin.A mean temperature above 25.9℃ after heading is required to improve the ECQ of rice.
基金supported by the National Natural Science Foundation of China(Grant Nos.42330610 and 42075010)。
文摘The Sichuan Basin(SCB),China has a high incidence of extremely persistent heavy rainfall(EPHR)events.The EPHR events from 2009 to 2019 in the SCB were mainly concentrated over the northern and northwestern windward slopes and the central basin.They occurred from June to September,but especially in July,and peaked at 0300 LST.ERA5 reanalysis data and objective classification were used to investigate the synoptic patterns and their effects.There were three synoptic patterns during EPHR events,all accompanied by a Southwest Vortex.The location and intensity of the Southwest Vortex,thermal forcing of the Tibetan Plateau(TP),and low-level winds can greatly affect the intensity and spatial distribution of EPHR.When the Southwest Vortex was located in the western SCB and there were southerly low-level jets(LLJs),convergence and upslope wind would lead to EPHR over the northwestern or northern windward slopes.If there was no LLJ and the whole SCB was under the center of the Southwest Vortex,nocturnal EPHR was controlled by the internal circulation of the Southwest Vortex and the updraft generated by the thermal forcing of the TP,and the rainfall was weaker.The southeastern entrance of the SCB was a key area where the low-level wind dominated the nocturnal peak of EPHR.The nocturnal strengthened southeasterly wind in the key area is attributable to inertial oscillation,and the topographic friction plays an essential role in transporting momentum and moisture into the basin by generating easterly and northeasterly ageostrophic winds.
基金supported by the National Natural Science Foundation of China(No.22072096).
文摘It is still a challenge to develop hierarchically nanostructured catalysts with simple approaches to enhance the low-temperature catalytic activity.Herein,a set of mesoporous Co-Cu binary metal oxides with different morphologies were successfully prepared via a facile ammonium bicarbonate precipitation method without any templates or surfactants,which were further applied for catalytic removal of carcinogenic toluene.Among the catalysts with different ratios,the CoCu_(0.2)composite oxide presented the best performance,where the temperature required for 90%conversion of toluene was only 237°C at the high weight hour space velocity(WHSV)of 240,000 mL/(gcat·hr).Meanwhile,compared to the related Co-Cu composite oxides prepared by using different precipitants(NaOH and H_(2)C_(2)O_(4)),the NH_(4)HCO_(3)-derived CoCu_(0.2)sample exhibited better catalytic efficiency in toluene oxidation,while the T90 were 22 and 28°C lower than those samples prepared by NaOH andH_(2)C_(2)O_(4)routes,respectively.Based on various characterizations,it could be deduced that the excellent performance was related to the small crystal size(6.7 nm),large specific surface area(77.0 m2/g),hollow hierarchical nanostructure with abundant high valence Co ions and adsorbed oxygen species.In situ DRIFTS further revealed that the possible reaction pathway for the toluene oxidation over CoCu_(0.2)catalyst followed the route of absorbed toluene→benzyl alcohol→benzaldehyde→benzoic acid→carbonate→CO_(2)and H_(2)O.In addition,CoCu_(0.2)sample could keep stable with long-time operation and occur little inactivation under humid condition(5 vol.%water),which revealed that the NH_(4)HCO_(3)-derived CoCu_(0.2)nanocatalyst possessed great potential in industrial applications for VOCs abatement.
基金Supported by the Key Science and Technology Program of Xizang Autonomous Region(No.XZ202301ZY0012N)the Key Fisheries Resources and Environmental Survey Project in the Southwest Region(No.CJW2023034)the National Natural Science Foundation of China(No.42306106)。
文摘A halophilic bacterium,named Halomonas sp.NEC-1 was isolated from the Nyer Co Salt Lake on the Xizang Plateau,SW China.The strain exhibited a broad pH tolerance range of 5-11,distinguishing it from Halomonas alkaliphila despite a 99% genetic similarity.Optimal growth conditions,determined through orthogonal experiments,were found to be 37℃,100-g/L salinity,and an initial pH of 6,resulting in a maximum OD_(600) of 7.98±0.06.Halomonas sp.NEC-1 produced 545.43±25.10 mg/L of ectoine under optimal conditions of 75-g/L salinity,40-g/L sodium glutamate,and an initial pH of 6.This production increased to 1388.81±3.69 mg/L after five rounds of hypo-osmotic shocks.During the shocks,ectoine productivity remained stable at approximately 16.29±0.04 to 17.28±0.48 mg/(L·h),representing a 43.40%-52.11% increase compared to the rate without any shock(11.36±1.05 mg/(L·h)).Additionally,the expression of the ectABC gene cluster,related to ectoine synthesis,significantly increased following the shocks,enhancing ectoine production.The ectoine extract demonstrated notable protective effects on Escherichia coli and plasmid DNA.After 10 min of exposure at 60℃,the colony count of E.coli treated with ectoine extract increased by 342% compared to treatment with distilled water.Furthermore,the ectoine extract protected plasmid DNA from 2,2′-Azobis(2-methylpropionamidine)dihydrochloride-induced damage.This study highlights Halomonas sp.NEC-1 is a promising strain for ectoine production and underscores the potential of microbial resources in salt lakes from Xizang region.
基金supported by the National Key Research and Development Project,No.2019YFA0112100(to SF).
文摘Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.
文摘短串联重复序列(short tandem repeat,STR)遗传标记在法庭科学DNA鉴定中占据绝对主导地位,包括中国在内的世界各国DNA数据库均基于STR遗传标记建立。STR遗传标记具有长度多态性和序列多态性。序列多态包括重复区和侧翼区序列的多态性。传统的基于毛细管电泳技术进行STR分型仅区分长度多态性,而深刻理解核心STR基因座的序列多态对于引物设计和DNA鉴定等方面至关重要。首先,STR扩增引物结合区的SNP、InDel可能干扰引物与DNA模板结合的亲和力,导致无法检测到某些等位基因或均衡性差,影响DNA鉴定准确性;其次,二代测序技术推动STR鉴定由长度多态分型向序列多态分型发展,显著提升了可检测的核心STR基因座多态信息含量,提高了其个体识别和亲缘关系分析效能;再者,不同人群具有不同的STR序列特征。近10年来,基于二代测序的STR序列多态性的研究逐渐增多,多个人群的序列多态性数据已经被报道,但以往的研究群体及数据较为零散,重复序列的数据格式不统一,导致核心STR基因座的序列多态性缺乏来自大数据的系统性总结和梳理。充分掌握核心STR基因座的序列特征对微量检材的个体识别、混合样本拆分、亲子鉴定中突变来源的确定等具有十分重要的意义。本文以19个常染色体核心STR为分析对象,整合了目前文献报道的群体数据和公开数据库中的中国人群变异频率数据,系统综述了这些STR的序列多态性,包括归纳STR基因座重复区的变异类型和分析变异规律,总结了中国人群中STR侧翼区的高频变异,并探讨了在STR序列检验中可能遇到的难点,以期为STR序列的应用解析、案件检验中稀有等位基因的判别以及STR试剂盒的研制等方面提供参考。
基金This work was supported by the projects of the China Geological Survey(DD 20221703).
文摘Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and exploitation.Both domestic and international natural gas hydrate production tests typically employ a single-well production model.Although this approach has seen some success,it continues to be hindered by low production rates and short production cycles.Therefore,there is an urgent need to explore a new well network to significantly increase the production of a single well.This paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field tests.It further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) replacement.On this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was proposed.The study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single well.Moreover,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate.
基金supported by the Neurosurgery Pain Research Institute at Johns Hopkins University and by the Lehner Family Foundation.
文摘Chronic pain after spine surgery(CPSS)is a complex disorder characterized by multifactorial pathogenesis that occurs in 8%–40%of patients undergoing lumbar spine surgery.We aimed to develop a rat model that mimics clinical CPSS conditions by taking two sequential surgical procedures.Step 1:A plastic rod was inserted into the left L5 intervertebral foramen to produce a steady compression on the dorsal root ganglion(DRG)and the spinal nerve,a common cause of low back pain(LBP).Step 2:The rod was removed after 7 days when rats exhibited mechanical and heat hypersensitivity in the ipsilateral hindpaw,followed by a full L5 laminectomy to mimic spine decompression surgery in LBP patients.The retention of the rod induced a prolonged LBP-like behavior but was quickly resolved after rod removal without laminectomy.However,rats that received laminectomy after rod removal developed heightened mechanical and heat sensitivity in the hindpaw,impaired gait,and reduced spontaneous exploration activity,indicating CPSS.Patch clamp recording revealed a significant augmentation in the intrinsic excitability of smalldiameter DRG neurons in CPSS rats.Administration of Dermorphin[D-Arg2,Lys4](1–4)amide(DALDA,5mg/kg,i.p.),a peripherally acting mu-opioid receptor(MOR)-preferred agonist,attenuated pain hypersensitivity,capsaicin-induced[Ca^(2+)]i rising and the increased intrinsic excitability of DRG neurons from CPSS rats.Our findings suggest that this new model,which mirrors the nature of CPSS developed in patients,may be useful for future studies of the underlying mechanisms.
基金the National Natural Science Foundation of China(No.41872232)。
文摘The Xing'an-Inner Mongolia Orogen is a critical tectonic unit for constraining the evolution of the Paleo-Asian Ocean.However,the location and time of the closure of the Paleo-Asian Ocean are still debated.Here,we select a representative basin in Dashizhai in northeastern China,using U-Pb zircon geochronology and geochemistry to analyze the sedimentary facies,depositional ages,and provenance.The results show that the ages of the Dashizhai Formation range from 400 to 347 Ma,the Shoushangou Formation range from 400 to 348 Ma,the Zhesi Formation range from 307 to 252 Ma,and the Linxi Formation range from 299 to 241 Ma.The Dashizhai Formation is composed of metamorphic andesite and clastic rocks.The Shoushangou Formation comprises siltstone,rhyolite,and argillaceous siltstone.The Zhesi and Linxi Formations are composed of mudstone and argillaceous siltstone.Geochemical data shows that these rocks are enriched in light rare earth elements and depleted in Eu with various La/Sc,Th/Sc,and La/Co ratios.The Permian Dashizhai Basin is from Permian volcanic and felsic igneous rocks from the Ergun,Xing'an,and Songliao blocks.The absence of the Late Carboniferous strata in the Dashizhai Basin indicates an extension setting during this period.Furthermore,we suggest the Xing'an-Inner Mongolia Orogen was an uplifting process associated with evolution the Paleo-Asian Ocean during the Late Permian.
基金supported by grants from the National Natural Science Foundation of China(52072099)Team program of the Natural Science Foundation of Heilongjiang Province,China(No.TD2021E005)Joint Guidance Project of the Natural Science Foundation of Heilongjiang Province,China(No.LH2022E093)。
文摘Electrocatalysts are an effective strategy to mitigate the shuttling effect of lithium polysulfides(LiPSs)and accelerate the redox kinetics of LiPSs in lithium-sulfur(Li-S)batteries.However,traditional electrocatalysts only have a single active site and often undergo structural collapse and aggregation during charging and discharging,resulting in reduced catalytic performance.Herein,the two-dimensional(2D)polar high-entropy La_(0.71)Sr_(0.29)Co_(0.21)Ni_(0.20)Fe_(0.19)Cr_(0.20)Cu_(0.20)O_(3)(LCO-HEO)nanosheets were rationally designed and successfully synthesized to address this issue.The distinct functional polar sites in LCOHEOs were formed by the d-d orbital hybridization between spatially coupling adjacent transition metals,which can strengthen the dipole-dipole interaction between polar LCO-HEOs and polar LiPSs.2D polar LCO-HEO nanosheets can efficiently capture and trigger the tandem catalysis of polar LiPSs during their sequential conversion.The S/LCO-HEO composite cathode exhibits a high specific capacity of 1161.1 mA h g^(-1)at 1.0 C,with an ultralow capacity attenuation rate of 0.036%per cycle over 1200 cycles,and achieves stable cycling for 1500 cycles even at 8.0 C.Furthermore,even with a high sulfur loading(5.5 mg cm^(-2))and a low electrolyte/sulfur(E/S)ratio(4.0μL mg^(-1)),the S/LCO-HEO composite cathode shows desirable sulfur utilization and good cycle stability.This work demonstrates the feasibility of high entropy-driven multiple distinct functional polar sites for high-rate and long-cycle Li-S batteries.
基金the National Natural Science Foundation of China(Nos.22071175,22071116)Tianjin Graduate Research and Innovation Project(No.2021YJSB196)and for financial supports。
文摘Benziodazole-triflate,as a novel heterocyclic hypervalent iodine(III)reagent,was prepared from the reaction of hypervalent chloroiodine(III)with silver triflate under mild conditions.The structure of this new reagent was elucidated by NMR spectroscopy and X-ray crystallography,and its reactions with diverseα-electron withdrawing group substituted carbonyl compounds were investigated.The results implied that benziodazole-triflate could be selectively used as both a 2-iodobenzamido-transfer reagent for the synthesis of oxazole compounds,and a triflate-transfer reagent for the triflation ofβ-keto-sulfones.Ionic mechanistic pathways,supported by density functional theory(DFT)calculations,were proposed to account for the divergent selectivities of the transformations.
基金supported by the Special Funds for Science and Technology Innovation on Carbon Peak Carbon Neutral of Jiangsu Province,China(No.BK20220017)the Natural Science Foundation of China(No.42007090)the National Key Research and Development Program of China(No.2021YFD22004)。
文摘Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitigate soil N losses,our understanding of its interaction with N fertilizer and its long-term effects remains limited owing to experimental constraints.In this study,two microcosm incubation experiments were performed to evaluate the effect of fresh biochar,compared to 8-year field-aged biochar application in a poplar plantation,on soil N_(2)O emissions triggered by biogas slurry application.The experiments incorporated three biochar levels and four biogas slurry application rates,each with three replicates.The results demonstrated that fresh and aged biochar significantly reduced soil cumulative N_(2)O emissions by 31%–61%and 75%–99%,respectively,over 7 d following biogas slurry application.However,these mitigating effects diminished over incubation time.The application of fresh biochar significantly reduced soil available organic carbon and potential denitrification rates,suggesting that it primarily suppressed soil N_(2)O emissions by limiting the supply of electron donors.In contrast,aged biochar had minimal impact on soil available organic carbon and generally enhanced the abundances of bacterial amoA,nirS,nirK,and nosZ genes.This suggests that the aged biochar potentially suppressed soil N_(2)O emissions by promoting complete denitrification.Partial least squares structure equation model(PLS-SEM)analysis corroborated the two different mechanisms regulating the inhibitory influence of fresh and aged biochar on soil N_(2)O emissions.The lower R^(2)of PLS-SEM analysis for aged biochar(R^(2)=0.256)compared to that for fresh biochar(R^(2)=0.798)indicates that other factors,such as biochar properties,potentially affect soil N_(2)O emissions and warrant further investigation.This study highlights the need to evaluate the long-term effect of biochar on soil N_(2)O emissions,owing to the dynamic changes in biochar and soil properties over time.
基金Supported by the Tianjin Key Laboratory of Marine Resources and Chemistry(Tianjin University of Science&Technology),Tianjin,China(No.202302)the National Natural Science Foundation of China(No.32460154)the China Postdoctoral Science Foundation(No.2023MD734227)。
文摘5-hydroxytryptamine(5-HT)is a biological monoamine neurotransmitter in the central nervous system and gonads of crustaceans to induce gonadal maturation.To better understand the effects of 5-HT and its receptors on reproductive development in Artemia,a 5-HT type 7 receptor gene(5-HT_(7Ar))was identified in parthenogenetic Artemia and characterized.Sequence analysis revealed that the open reading frame of 5-HT_(7Ar) encodes a 414-aa protein.5-HT_(7Ar) showed higher expression in both brain and ovary at early embryo stage,5-HT_(7Ar) could be detected during ovarian development and the highest expression was observed at early embryo stage.Silencing of the 5-HT_(7Ar) in Artemia at early embryo stage decreased significantly the expression level of 5-HT_(7Ar) gene and protein at late oocyte,early embryo,and late embryo stage.Moreover,silencing of the 5-HT_(7Ar) resulted in a decreased fecundity,which corresponds to abnormal oocytes during the embryo development.Artemia tended to produce nauplii after the silencing of 5-HT_(7Ar),indicating that 5-HT_(7Ar) may also involve in the determination of its reproduction mode.The findings of this study provide an insight into the regulation of reproductive development in Artemia and the function of 5-HT_(7Ar).
文摘Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical properties.As a result,surface chemistry research plays a crucial role in various fields such as catalysis,energy,materials,quantum,and microelectronics.Surface science mainly investigates the correspondence between surface property and functionality.Scanning probe microscopy(SPM)techniques are important tools to characterize surface properties because of the capability of atomic-scale imaging,spectroscopy and manipulation at the single-atom level.In this review,we summarize recent advances in surface electronic,magnetic and optical properties characterized mainly by SPM-based methods.We focus on elucidating theπ-magnetism in graphene-based nanostructures,construction of spin qubits on surfaces,topology properties of surface organic structures,STM-based light emission,tip-enhanced Raman spectroscopy and integration of machine learning in SPM studies.
基金supported by the National Natural Science Foundation of China(Grant Nos.81902617 and 82100816)Guangdong Natural Science Foundation(Grant No.2021A1515012322)Guangzhou Basic and Applied Basic Research Subject-Young Doctor’s“Sailing”Project(Grant No.2024A04J4702).
文摘Background:U2AF homology motif kinase 1(UHMK1)has been associated with RNA processing and protein phosphorylation,thereby influencing tumor progression.The study aimed to explore its regulatory mechanisms and biological functions in human prostate cancer(PCa).Methods:In this study,we systematically evaluated the expression and prognostic significance of UHMK1 in public databases,followed by validation through immunohis-tochemistry(IHC)in PCa specimens.Both gain-of-function and loss-of-function experiments were conducted to elucidate the role of UHMK1 in vitro and in vivo.Additionally,a series of molecular and biochemical assays were performed to investigate the regulatory mechanisms underlying UHMK1 activity.Results:Our findings revealed that UHMK1 expression was significantly upregulated in PCa tissues and correlated with poor patient prognosis,as demonstrated by analysis of public datasets and confirmed by immunohistochemical staining.Functional studies showed that UHMK1 depletion suppressed tumor cell proliferation and metastasis,while its overexpression promoted these processes.Mechanistically,we identified that UHMK1 phosphorylates nuclear receptor coactivator 3(NCOA3),which subsequently activates activating transcription factor 4(ATF4)to upregulate methylenetetrahydrofolate dehy-drogenase 2(MTHFD2)transcription.Interestingly,MTHFD2 was found to reciprocally enhance UHMK1 expression,establishing a positive feedback loop.Conclusions:In conclusion,our data suggest that the UHMK1-MTHFD2 axis forms a positive feedback loop that drives PCa progression.Targeting this loop represents a promising therapeutic strategy for restraining prostate cancer development and progression.
基金financially supported by the Natural Science Foundation of China(52071065)the Fundamental Research Funds for the Central Universities(N2007007)the National Key R&D Program of China(2016YFB-0301201)。
文摘The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mechanical properties.In this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced.This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings,employing both experimental approaches and ProCast simulation methodologies.The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains.Under the condition of pouring temperature of 1,600℃,rotation speed of 800 r·min^(-1) and pouring time of 6 s,the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa,and the tensile strength at 800℃ reaches 705 MPa,which is significantly higher than that of traditional as-cast Ti-Al alloy.
基金The National Key R&D Program of China under contract No.2023YFE0126300the National Natural Science Foundation of China under contract No.41930538the Open Fund of China Meteorological Administration Hydro-Meteorology Key Laboratory,Hohai University,under contract No.23SWQXM049.
文摘Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wave energy storage but is also affected by the local available wave probability.Different distributions and trends between the available wave energy and total wave energy storage are observed.Larger values of total wave energy storage are concentrated in the high-latitude westerlies zone,whereas available wave energy storage exhibits greater concentration in the middle-low latitude regions.In each basin,there is a notable upward trend in both total wave energy storage and available wave energy storage.However,the northern Hemisphere(NH)exhibits an increasing trend in available wave probability,whereas the southern Hemisphere(SH)experiences a decreasing trend.This divergence contributes to the spatial distributions of available wave energy storage becoming increasingly uniform.These trends in wave energy are primarily influenced by changes in significant wave height.Although the increasing trend of significant wave height across all frequency ranges induces the growth of total wave energy storage,only the increasing of wave heights falling in 1.3−4 m can cause the growth of available wave energy storage.The consistent increasing rates of wave height under different mean levels contribute to the divergent trends in available wave probability.
