Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herei...Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herein,we designed a novel nanozyme(P@Co)comprised of polydopamine(PDA)nanoparticles(NPs)loading with ultra-small Co,combining with near infrared(NIR)irradiation,which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI.For lipopolysaccharide(LPS)induced macrophages,P@Co+NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels,decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)as well as inducing macrophage M2 directional polarization.Significantly,it displayed the outstanding activities of lowering acute lung inflammation,relieving diffuse alveolar damage,and up-regulating heat shock protein 70(HSP70)expression,resulting in synergistic enhanced ALI therapy effect.It offers a novel strategy for the clinical treatment of ROS related diseases.展开更多
Diffusive carbon dioxide （CO2） emissions from the water surface of the Three Gorges Reservoir, currently the largest hydroelectric reservoir in the world, were measured using floating static chambers over the course...Diffusive carbon dioxide （CO2） emissions from the water surface of the Three Gorges Reservoir, currently the largest hydroelectric reservoir in the world, were measured using floating static chambers over the course of a yearlong survey. The results showed that the average,annual CO2 flux was （163.3 ± 117.4） mg CO2/（m^2.hr） at the reservoir surface, which was larger than the CO2 flux in most boreal and temperate reservoirs but lower than that in tropical reservoirs. Significant spatial variations in CO2 flux were observed at four measured sites, with the largest flux measured at Wushan （221.9 mg CO2/（m^2.hr）） and the smallest flux measured at Zigui （88.6 mg CO2/（m^2.hr））; these differences were probably related to the average water velocities at different sites. Seasonal variations in CO2 flux were also observed at four sites, starting to increase in January, continuously rising until peaking in the summer （June-August） and gradually decreasing thereafter. Seasonal variations in CO2 flux could reflect seasonal dynamics in pH, water velocity, and temperature. Since the spatial and temporal variations in CO2 flux were significant and dependent on multiple physical, chemical, and hydrological factors, it is suggested that long-term measurements should be made on a large spatial scale to assess the climatic influence of hydropower in China, as well as the rest of the world.展开更多
As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies hav...As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies have investigated the influences of tillage on the responses of soil CO2 efflux （SCE） to soil temperature and moisture. Using a multi-channel automated CO2 efflux chamber system, we measured SCE in situ continuously before and after the conventional tillage in a rain fed wheat field of Loess Plateau, China. The changes in soil temperature and moisture sensitivities of SCE, denoted by the Q10 value and linear regression slope respectively, were compared in the same range of soil temperature and moisture before and after the tillage. The results showed that, after the tillage, SCE increased by 1.2-2.2 times; the soil temperature sensitivity increased by 36.1%-37.5%; and the soil moisture sensitivity increased by 140%-166%. Thus, the tillage-induced increase in SCE might partially be attributed to the increases in temperature and moisture sensitivity of SCE.展开更多
Molybdenum carbide(MO_(2)C)materials are promising electrocatalysts with potential applications in hydrogen evolution reaction(HER)due to low cost and Pt-like electronic structures.Nevertheless,their HER activity is u...Molybdenum carbide(MO_(2)C)materials are promising electrocatalysts with potential applications in hydrogen evolution reaction(HER)due to low cost and Pt-like electronic structures.Nevertheless,their HER activity is usually hindered by the strong hydrogen binding energy.Moreover,the lack of water-cleaving site's makes it difficult for the catalysts to work in alkaline solutions.Here,we designed and synthesized a B and N dual-doped carbon layer that encapsulated on MO_(2)C nanocrystals(MO_(2)C@BNC)for accelerating HER under alkaline condition.The electronic interactions between the MO_(2)C nanocrystals and the multiple-doped carbon layer endow a near-zero H adsorption Gibbs free energy on the defective C atoms over the carbon shell.Meanwhile,the introduced B atoms afford optimal H_2O adsorption sites for the water-cleaving step.Accordingly,the dual-doped MO_(2)C catalyst with synergistic effect of non-metal sites delivers superior HER performances of a low overpotential(99 mV@10 mA cm^(-2))and a small Tafel slope(58.1 mV dec^(-1))in 1 M KOH solution.Furthermore,it presents a remarkable activity that outperforming the commercial 10%Pt/C catalyst at large current density,demonstrating its applicability in industrial water splitting.This study provides a reasonable design strategy towards noble-metal-free HER catalysts with high activity.展开更多
The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined ...The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined with the cosmic-ray-induced background make these measurements highly challenging,particularly for capture reactions.This work demonstrates the second configuration of the large-scale modular BGO detection array(LAMBDA-Ⅱ)designed to capture reaction measurements and introduces a method for suppressingγ-ray detection background in ground laboratories.By employing active and passive shielding,the background of LAMBDA-Ⅱwas significantly reduced by approximately two orders of magnitude,reaching 8.1×10^(-3)and 1.0×10^(-3)keV^(-1)h^(-1)in the 6-11 and 11-20 MeV energy ranges,respectively.When combined with a mA-scale intensity beam,this reduced background enables the investigation of several capture reactions of astrophysical interest in ground laboratories.展开更多
In the context of the rapid advancement of intelligent manufacturing,ensuring the alignment of the skill levels of embedded system developers with industry requirements has emerged as a crucial aspect in the reform of...In the context of the rapid advancement of intelligent manufacturing,ensuring the alignment of the skill levels of embedded system developers with industry requirements has emerged as a crucial aspect in the reform of vocational education.This research delves into a three-stage progressive talent cultivation model denoted as“Cultivation–Growth–Incubation”,which is founded on the Shi Zhenjiang(Z.S.)Intelligent Embedded System Development Master Skills Studio.By means of hierarchical training,project-driven strategies,and industry-academia cooperation,this model effectively elevates students’application capabilities and innovative competencies in embedded systems.Case analyses illustrate the practical efficacy of the model,providing valuable references for the establishment of master skills studios in vocational education.展开更多
Dance video is an innovative form that integrates dance art with imaging technology,enriching the expression of dance through techniques such as photography,videography,and special effects.This paper explores the defi...Dance video is an innovative form that integrates dance art with imaging technology,enriching the expression of dance through techniques such as photography,videography,and special effects.This paper explores the definition,current development,artistic expression,social impact,and future trends of dance video.Through narrative construction,visual impact,emotional resonance,technological innovation,and cultural expression,dance video enhances the narrative and visual appeal of dance.In the future,dance video will focus more on the integration of virtual reality(VR)and augmented reality(AR)technologies.However,it also faces challenges such as rapid technological updates,maintaining artistic originality,and balancing commercial interests.展开更多
Urban areas are the major anthropogenic source of atmospheric CO_(2),thus making longterm and continuous observations of their carbon emission dynamics extremely important.The COVID-19 lockdown served as a natural exp...Urban areas are the major anthropogenic source of atmospheric CO_(2),thus making longterm and continuous observations of their carbon emission dynamics extremely important.The COVID-19 lockdown served as a natural experiment that provided a unique opportunity to analyse the contribution of human activities to CO_(2) emissions from urban areas.In 2020,Beijing experienced COVID-19 confinement with different levels of restrictions on social mobility and economic activity,resulting in reductions in CO_(2) emissions.To investigate the response mechanisms of CO_(2) flux to restriction measures,we analysed CO_(2) flux data obtained using the eddy covariance technique from 2015 to 2020,and compared CO_(2) flux during the COVID-19 confinement period in 2020 with the preceding years(2015-2019)and across various levels of confinement.The results showed that:(1)the annual CO_(2) flux was 2.1±0.2 kg C/(m^(2)·yr)in 2020,which showed a significant reduction of 31.8%compared to the adjacent 2019;(2)the reduction in CO_(2) flux was closely related to the level of restrictions on human activities;(3)most reductions occurred during the morning(85.7%)and evening(32.7%)peak traffic times,indicating that commuting-related transportation is a primary contributor to urban CO_(2) emissions.It is suggested that measures that reduce transportation-related CO_(2) sources should be considered as priorities for reducing urban CO_(2) emissions.The dynamic variation of urban CO_(2) flux captured by the eddy covariance technology is conductive to strengthening the supervision of the implementation of urban carbon emission reduction policies,promoting the achievement of dual carbon goals.展开更多
Recently reported summertime methane （CH4） emissions （6.7 ± 13.3 mg CH4/（m2·hr）） from newly created marshes in the drawdown area of the Three Gorges Reservoir （TGR）, China have triggered broad concer...Recently reported summertime methane （CH4） emissions （6.7 ± 13.3 mg CH4/（m2·hr）） from newly created marshes in the drawdown area of the Three Gorges Reservoir （TGR）, China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and gas chromatography. The average CH4 emission flux from permanently flooded areas in Zigui, Wushan and Yunyang Counties was （0.33 ± 0.09） mg CH4/（m2·hr）. In half of these hottest months of the year, the wilderness, cropland and deforested drawdown sites were aerobic and located above water level, and the CH4 emissions were very small, ranging from a sink at 0.12 mg CH4/（m2·hr） to a source at 0.08 mg CH4/（m2·hr） except for one mud-covered site after flood. Mean CH4 emission in flooded drawdown sites was 0.34 mg CH4/（m2·hr）. The emissions from the rice paddy sites in the drawdown area were averaged at （4.86 ± 2.31） mg CH4/（m2·hr）. Excepting the rice-paddy sites, these results show much lower emission levels than previously reported. Our results indicated considerable spatial and temporal variation in CH4 emissions from the TGR. Human activities and occasional events, such as flood, may also affect emission levels. Long-term CH4 measurements and modeling in a large region are necessary to accurately estimate greenhouse gas emissions from the TGR.展开更多
A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype ...A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.展开更多
The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its poten...The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields.Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.展开更多
The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback o...The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in warmed environment. Soil warming effect on net ecosystem exchange （NEE） of carbon dioxide during the transition period from winter to spring was investigated in a temperate urban lawn in Beijing, China. The NEE （negative for uptake） under soil warming treatment （temperature was about 5~C higher than the ambient treatment as a control） was -0.71 ~mol/（m2.sec）, the ecosytem was a CO2 sink under soil warming treatment, the lawn ecosystem under the control was a CO2 source （0.13 Ixmol/（mE.sec））, indicating that the lawn ecosystem would provide a negative feedback to global warming. There was no significant effect of soil warming on nocturnal NEE （i.e., ecosystem respiration）, although the soil temperature sensitivity （Q10） of ecosystem respiration under soil warming treatment was 3.86, much lower than that in the control （7.03）. The CO2 uptake was significantly increased by soil warming treatment that was attributed to about 100% increase of ct （apparent quantum yield） and Amax （maximum rate of photosynthesis）. Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global warming than respiration in the transition period.展开更多
Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, w...Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.展开更多
Toxoplasma gondii is a worldwide parasite that can infect almost all kinds of mammals and cause fatal toxoplasmosis in immunocompromised patients.Apoptosis is one of the principal strategies of host cells to clear pat...Toxoplasma gondii is a worldwide parasite that can infect almost all kinds of mammals and cause fatal toxoplasmosis in immunocompromised patients.Apoptosis is one of the principal strategies of host cells to clear pathogens and maintain organismal homeostasis,but the mechanism of cell apoptosis induced by T.gondii remains obscure.To explore the apoptosis influenced by T.gondii,Vero cells infected or uninfected with the parasite were subjected to apoptosis detection and subsequent dual RNA sequencing(RNA-seq).Using high-throughput Illumina sequencing and bioinformatics analysis,we found that pro-apoptosis genes such as DNA damage-inducible transcript 3(DDIT3),growth arrest and DNA damage-inducibleα(GADD45 A),caspase-3(CASP3),and high-temperature requirement protease A2(Htr A2)were upregulated,and anti-apoptosis genes such as poly(adenosine diphosphate(ADP)-ribose)polymerase family member 3(PARP3),B-cell lymphoma 2(Bcl-2),and baculoviral inhibitor of apoptosis protein(IAP)repeat containing 5(BIRC5)were downregulated.Besides,tumor necrosis factor(TNF)receptor-associated factor 1(TRAF1),TRAF2,TNF receptor superfamily member 10 b(TNFRSF10 b),disabled homolog2(DAB2)-interacting protein(DAB2 IP),and inositol 1,4,5-trisphosphate receptor type 3(ITPR3)were enriched in the upstream of TNF,TNF-related apoptosis-inducing ligand(TRAIL),and endoplasmic reticulum(ER)stress pathways,and TRAIL-receptor2(TRAIL-R2)was regarded as an important membrane receptor influenced by T.gondii that had not been previously considered.In conclusion,the T.gondii RH strain could promote and mediate apoptosis through multiple pathways mentioned above in Vero cells.Our findings improve the understanding of the T.gondii infection process through providing new insights into the related cellular apoptosis mechanisms.展开更多
BACKGROUND Long non-coding RNAs(lncRNAs) have been shown to be associated with many tumors. However, the specific mechanism of lncRNAs in the occurrence and development of gastric cancer(GC) has not been fully elucida...BACKGROUND Long non-coding RNAs(lncRNAs) have been shown to be associated with many tumors. However, the specific mechanism of lncRNAs in the occurrence and development of gastric cancer(GC) has not been fully elucidated.AIM To explore the expression level and molecular mechanism of HOXD-AS2 in GC tissues and cells, and analyze its significance in the prognosis of GC.METHODS Real-time quantitative PCR was used to detect the expression of HOXD-AS2 in 79 pairs of GC tissues and five cell lines. The pc HOXD-AS2 plasmid vector was constructed and transfected into SGC-7901 and SNU-1 GC cells. Matrigel Transwell and wound healing assays were used to confirm the effect of HOXDAS2 on invasion and migration of GC cells. Cell counting kit-8 assay and flow cytometry were used to verify the effect of HOXD-AS2 on the proliferation, cell cycle, and apoptosis of GC cells. The relevant regulatory mechanism between HOXD-AS2 and HOXD8 and PI3K/Akt signaling pathway was verified by Western blot analysis.RESULTS The low expression of lncRNA HOXD-AS2 was associated with lymph node metastasis and tumor-node-metastasis stage in GC. In vitro functional experiments demonstrated that overexpression of HOXD-AS2 inhibited GC cell progression. Mechanistic studies revealed that HOXD-AS2 regulated the expression of its nearby gene HOXD8 and inhibited the activity of the PI3K/Akt signaling pathway.CONCLUSION These results indicate that downregulation of HOXD-AS2 significantly promotes the progression of GC cells by regulating HOXD8 expression and activating the PI3K/Akt signaling pathway. HOXD-AS2 may be a novel diagnostic biomarker and effective therapeutic target for GC.展开更多
The response functions of a 4π summing BGO detector were established using extensive experimental measurements and GEANT4 simulation. The partial and total efficiencies for all components of the γ-ray interaction wi...The response functions of a 4π summing BGO detector were established using extensive experimental measurements and GEANT4 simulation. The partial and total efficiencies for all components of the γ-ray interaction with the BGO detector were also measured. These response functions and efficiencies will be used in the β-Oslo method experiments to study the neutron capture cross sections of radioactive heavy ions. The application of the response functions of the BGO detector under simulated continuum γ-rays and source measurement γ-rays proves that the method and response functions are reliable.展开更多
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e...Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.展开更多
基金financially supported by the Key Research&Development Program of Guangxi(No.GuiKeAB22080088)the Joint Project on Regional High-Incidence Diseases Research of Guangxi Natural Science Foundation(No.2023GXNSFDA026023)+3 种基金the Natural Science Foundation of Guangxi(No.2023JJA140322)the National Natural Science Foundation of China(No.82360372)the High-level Medical Expert Training Program of Guangxi“139 Plan Funding(No.G202003010)the Medical Appropriate Technology Development and Popularization and Application Project of Guangxi(No.S2020099)。
文摘Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herein,we designed a novel nanozyme(P@Co)comprised of polydopamine(PDA)nanoparticles(NPs)loading with ultra-small Co,combining with near infrared(NIR)irradiation,which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI.For lipopolysaccharide(LPS)induced macrophages,P@Co+NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels,decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)as well as inducing macrophage M2 directional polarization.Significantly,it displayed the outstanding activities of lowering acute lung inflammation,relieving diffuse alveolar damage,and up-regulating heat shock protein 70(HSP70)expression,resulting in synergistic enhanced ALI therapy effect.It offers a novel strategy for the clinical treatment of ROS related diseases.
基金supported by the National Natural Science Foundation of China(No.50809067,41303065)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA05060102,XDA05050602)+1 种基金the Project of Zhejiang Key Scientific and Technological Innovation Team(No.2010R50039)the Project of Zhejiang Scientific and Technological Plan(No.2011F20025)
文摘Diffusive carbon dioxide （CO2） emissions from the water surface of the Three Gorges Reservoir, currently the largest hydroelectric reservoir in the world, were measured using floating static chambers over the course of a yearlong survey. The results showed that the average,annual CO2 flux was （163.3 ± 117.4） mg CO2/（m^2.hr） at the reservoir surface, which was larger than the CO2 flux in most boreal and temperate reservoirs but lower than that in tropical reservoirs. Significant spatial variations in CO2 flux were observed at four measured sites, with the largest flux measured at Wushan （221.9 mg CO2/（m^2.hr）） and the smallest flux measured at Zigui （88.6 mg CO2/（m^2.hr））; these differences were probably related to the average water velocities at different sites. Seasonal variations in CO2 flux were also observed at four sites, starting to increase in January, continuously rising until peaking in the summer （June-August） and gradually decreasing thereafter. Seasonal variations in CO2 flux could reflect seasonal dynamics in pH, water velocity, and temperature. Since the spatial and temporal variations in CO2 flux were significant and dependent on multiple physical, chemical, and hydrological factors, it is suggested that long-term measurements should be made on a large spatial scale to assess the climatic influence of hydropower in China, as well as the rest of the world.
基金supported by the National Natural Science Foundation of China (No.71003092)the National Basic Research Program (973) of China (No.2010CB833504-2)
文摘As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies have investigated the influences of tillage on the responses of soil CO2 efflux （SCE） to soil temperature and moisture. Using a multi-channel automated CO2 efflux chamber system, we measured SCE in situ continuously before and after the conventional tillage in a rain fed wheat field of Loess Plateau, China. The changes in soil temperature and moisture sensitivities of SCE, denoted by the Q10 value and linear regression slope respectively, were compared in the same range of soil temperature and moisture before and after the tillage. The results showed that, after the tillage, SCE increased by 1.2-2.2 times; the soil temperature sensitivity increased by 36.1%-37.5%; and the soil moisture sensitivity increased by 140%-166%. Thus, the tillage-induced increase in SCE might partially be attributed to the increases in temperature and moisture sensitivity of SCE.
基金supported by the National Natural Science Foundation of China(Grant No.52202310)Natural Science Foundation of Jiangsu Province(Grant No.BK20191443)+7 种基金the Qinglan ProjectYouth Hundred Talents Programthe Toptalent Program of Yangzhou Universitythe Innovation technology platform project(YZ2020268)jointly built by Yangzhou City and Yangzhou UniversityPostgraduate Research&Practice Innovation Program of Jiangsu Province(SJCX22_1703)the Key Research and Development Projects of Sichuan Province(23ZDYF0466)“Tianfu Emei”Science and Technology Innovation Leader Program in Sichuan ProvinceUniversity of Electronic Science and Technology of China Talent Start-up Funds(A1098531023601208)。
文摘Molybdenum carbide(MO_(2)C)materials are promising electrocatalysts with potential applications in hydrogen evolution reaction(HER)due to low cost and Pt-like electronic structures.Nevertheless,their HER activity is usually hindered by the strong hydrogen binding energy.Moreover,the lack of water-cleaving site's makes it difficult for the catalysts to work in alkaline solutions.Here,we designed and synthesized a B and N dual-doped carbon layer that encapsulated on MO_(2)C nanocrystals(MO_(2)C@BNC)for accelerating HER under alkaline condition.The electronic interactions between the MO_(2)C nanocrystals and the multiple-doped carbon layer endow a near-zero H adsorption Gibbs free energy on the defective C atoms over the carbon shell.Meanwhile,the introduced B atoms afford optimal H_2O adsorption sites for the water-cleaving step.Accordingly,the dual-doped MO_(2)C catalyst with synergistic effect of non-metal sites delivers superior HER performances of a low overpotential(99 mV@10 mA cm^(-2))and a small Tafel slope(58.1 mV dec^(-1))in 1 M KOH solution.Furthermore,it presents a remarkable activity that outperforming the commercial 10%Pt/C catalyst at large current density,demonstrating its applicability in industrial water splitting.This study provides a reasonable design strategy towards noble-metal-free HER catalysts with high activity.
基金Supported by the National Key R&D Program of China(Nos.2022YFA1602301,2022YFA1603300,and 2023YFA1606701)National Natural Science Foundation of China(Nos.U1867211,12275026,and 12222514)the CAS Light of West China Program grant No.2020-82。
文摘The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined with the cosmic-ray-induced background make these measurements highly challenging,particularly for capture reactions.This work demonstrates the second configuration of the large-scale modular BGO detection array(LAMBDA-Ⅱ)designed to capture reaction measurements and introduces a method for suppressingγ-ray detection background in ground laboratories.By employing active and passive shielding,the background of LAMBDA-Ⅱwas significantly reduced by approximately two orders of magnitude,reaching 8.1×10^(-3)and 1.0×10^(-3)keV^(-1)h^(-1)in the 6-11 and 11-20 MeV energy ranges,respectively.When combined with a mA-scale intensity beam,this reduced background enables the investigation of several capture reactions of astrophysical interest in ground laboratories.
基金The 2025 Guangdong Polytechnic College Innovation-driven School Strengthening Project“Construction of Shi Zhenjiang’s Master Studio for Intelligent Embedded System Development Skills”(Project No.:2025CQ06-05)。
文摘In the context of the rapid advancement of intelligent manufacturing,ensuring the alignment of the skill levels of embedded system developers with industry requirements has emerged as a crucial aspect in the reform of vocational education.This research delves into a three-stage progressive talent cultivation model denoted as“Cultivation–Growth–Incubation”,which is founded on the Shi Zhenjiang(Z.S.)Intelligent Embedded System Development Master Skills Studio.By means of hierarchical training,project-driven strategies,and industry-academia cooperation,this model effectively elevates students’application capabilities and innovative competencies in embedded systems.Case analyses illustrate the practical efficacy of the model,providing valuable references for the establishment of master skills studios in vocational education.
基金National Social Science Fund of the Chongqing,China(Grant No.2023PY86)。
文摘Dance video is an innovative form that integrates dance art with imaging technology,enriching the expression of dance through techniques such as photography,videography,and special effects.This paper explores the definition,current development,artistic expression,social impact,and future trends of dance video.Through narrative construction,visual impact,emotional resonance,technological innovation,and cultural expression,dance video enhances the narrative and visual appeal of dance.In the future,dance video will focus more on the integration of virtual reality(VR)and augmented reality(AR)technologies.However,it also faces challenges such as rapid technological updates,maintaining artistic originality,and balancing commercial interests.
基金supported by the National Key Research Program of China(No.2017YFE0127700)the National Natural Science Foundation of China(No.42301325)China Postdoctoral Science Foundation(Nos.2023M743704 and 2024T170975)。
文摘Urban areas are the major anthropogenic source of atmospheric CO_(2),thus making longterm and continuous observations of their carbon emission dynamics extremely important.The COVID-19 lockdown served as a natural experiment that provided a unique opportunity to analyse the contribution of human activities to CO_(2) emissions from urban areas.In 2020,Beijing experienced COVID-19 confinement with different levels of restrictions on social mobility and economic activity,resulting in reductions in CO_(2) emissions.To investigate the response mechanisms of CO_(2) flux to restriction measures,we analysed CO_(2) flux data obtained using the eddy covariance technique from 2015 to 2020,and compared CO_(2) flux during the COVID-19 confinement period in 2020 with the preceding years(2015-2019)and across various levels of confinement.The results showed that:(1)the annual CO_(2) flux was 2.1±0.2 kg C/(m^(2)·yr)in 2020,which showed a significant reduction of 31.8%compared to the adjacent 2019;(2)the reduction in CO_(2) flux was closely related to the level of restrictions on human activities;(3)most reductions occurred during the morning(85.7%)and evening(32.7%)peak traffic times,indicating that commuting-related transportation is a primary contributor to urban CO_(2) emissions.It is suggested that measures that reduce transportation-related CO_(2) sources should be considered as priorities for reducing urban CO_(2) emissions.The dynamic variation of urban CO_(2) flux captured by the eddy covariance technology is conductive to strengthening the supervision of the implementation of urban carbon emission reduction policies,promoting the achievement of dual carbon goals.
基金supported by the National Natural Science Foundation of China (No. 50809067)the National Basic Research Program (973) of China (No.2010CB955904-03)the Chinese Academy of Sciences for Strategic Priority Research Program (No.XDA05060102, XDA05050602)
文摘Recently reported summertime methane （CH4） emissions （6.7 ± 13.3 mg CH4/（m2·hr）） from newly created marshes in the drawdown area of the Three Gorges Reservoir （TGR）, China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and gas chromatography. The average CH4 emission flux from permanently flooded areas in Zigui, Wushan and Yunyang Counties was （0.33 ± 0.09） mg CH4/（m2·hr）. In half of these hottest months of the year, the wilderness, cropland and deforested drawdown sites were aerobic and located above water level, and the CH4 emissions were very small, ranging from a sink at 0.12 mg CH4/（m2·hr） to a source at 0.08 mg CH4/（m2·hr） except for one mud-covered site after flood. Mean CH4 emission in flooded drawdown sites was 0.34 mg CH4/（m2·hr）. The emissions from the rice paddy sites in the drawdown area were averaged at （4.86 ± 2.31） mg CH4/（m2·hr）. Excepting the rice-paddy sites, these results show much lower emission levels than previously reported. Our results indicated considerable spatial and temporal variation in CH4 emissions from the TGR. Human activities and occasional events, such as flood, may also affect emission levels. Long-term CH4 measurements and modeling in a large region are necessary to accurately estimate greenhouse gas emissions from the TGR.
基金supported by the National Key Research and Development Program of China(Nos.2016YFA0400502 and 2015CB856904)the National Natural Science Foundation of China(Nos.U1332129,11475243,11421505,11775288 and 11405005)the ‘‘100-talent plan’’ of Shanghai Institute of Applied Physics from the Chinese Academy of Sciences(Nos.Y290061011 and Y526011011)
文摘A prototype thick-GEM-based cooling storage ring external-target experiment(CEE) time projection chamber(TPC) is constructed and tested with the pulsed ultraviolet laser beams. The results indicate that the prototype TPC has a good performance in three-dimensional track resolution. In X direction the position resolution is about 0.2 mm, and in Y direction the position resolution is about 0.5 mm. The results also determine that the energy resolution is about 5.4%, which achieve the requirements of the CEE experiment and can be used to study the nuclear state equation and the quantum chromo dynamics.
基金supported by the National Natural Science Foundation of China (No. 41371538)international cooperative project of the Chinese Academy of Sciences (No. KZCX2-YW-T13)the Innovation Project of the State Key Laboratory of Urban and Regional Ecology of China (No. SKLURE2013-1-02)
文摘The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields.Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.
基金supported by the National Natural Science Foundation of China (No. 41030744,31170424)the Chinese Academy of Sciences for Strategic Priority Research Program (No. XDA05050602,XDA05060102)
文摘The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in warmed environment. Soil warming effect on net ecosystem exchange （NEE） of carbon dioxide during the transition period from winter to spring was investigated in a temperate urban lawn in Beijing, China. The NEE （negative for uptake） under soil warming treatment （temperature was about 5~C higher than the ambient treatment as a control） was -0.71 ~mol/（m2.sec）, the ecosytem was a CO2 sink under soil warming treatment, the lawn ecosystem under the control was a CO2 source （0.13 Ixmol/（mE.sec））, indicating that the lawn ecosystem would provide a negative feedback to global warming. There was no significant effect of soil warming on nocturnal NEE （i.e., ecosystem respiration）, although the soil temperature sensitivity （Q10） of ecosystem respiration under soil warming treatment was 3.86, much lower than that in the control （7.03）. The CO2 uptake was significantly increased by soil warming treatment that was attributed to about 100% increase of ct （apparent quantum yield） and Amax （maximum rate of photosynthesis）. Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global warming than respiration in the transition period.
基金supported by the National Natural Science Foundation of China (Nos. 42101290 and 71533005)the Special Project on National Science and Technology Basic Resources Investigation of China (No. 2021FY100703)。
文摘Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index(NRUEI). We then calculated the 2016 index for 165 cities in China,and investigated what caused it to vary. We found three main results:(1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency(EUE), water utilization efficiency(WUE) and land utilization efficiency(LUE);(2) the NRUEI showed a significant positive correlation with a city’s population size,economy(Gross Domestic Product(GDP)), and the level of urban social development(GDP per capita);(3) cities in East China have the highest natural resource utilization efficiency,while cities in Northeast China have the lowest. These results indicate that China’s increasing urban development is associated with rising natural resource utilization efficiency and that the city’s endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city’s NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.
基金supported by the National Natural Science Foundation of China(Nos.81802037,81871684)the Qingshan Lake United Fund of Zhejiang Province(No.LQY19H190002)+2 种基金the Zhejiang Provincial Natural Science Foundation of China(No.LY22H190003)the Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talentsthe Basic Scientific Research Funds of Department of Education of Zhejiang Province(Nos.KYZD202104 and KYYB202101),China。
文摘Toxoplasma gondii is a worldwide parasite that can infect almost all kinds of mammals and cause fatal toxoplasmosis in immunocompromised patients.Apoptosis is one of the principal strategies of host cells to clear pathogens and maintain organismal homeostasis,but the mechanism of cell apoptosis induced by T.gondii remains obscure.To explore the apoptosis influenced by T.gondii,Vero cells infected or uninfected with the parasite were subjected to apoptosis detection and subsequent dual RNA sequencing(RNA-seq).Using high-throughput Illumina sequencing and bioinformatics analysis,we found that pro-apoptosis genes such as DNA damage-inducible transcript 3(DDIT3),growth arrest and DNA damage-inducibleα(GADD45 A),caspase-3(CASP3),and high-temperature requirement protease A2(Htr A2)were upregulated,and anti-apoptosis genes such as poly(adenosine diphosphate(ADP)-ribose)polymerase family member 3(PARP3),B-cell lymphoma 2(Bcl-2),and baculoviral inhibitor of apoptosis protein(IAP)repeat containing 5(BIRC5)were downregulated.Besides,tumor necrosis factor(TNF)receptor-associated factor 1(TRAF1),TRAF2,TNF receptor superfamily member 10 b(TNFRSF10 b),disabled homolog2(DAB2)-interacting protein(DAB2 IP),and inositol 1,4,5-trisphosphate receptor type 3(ITPR3)were enriched in the upstream of TNF,TNF-related apoptosis-inducing ligand(TRAIL),and endoplasmic reticulum(ER)stress pathways,and TRAIL-receptor2(TRAIL-R2)was regarded as an important membrane receptor influenced by T.gondii that had not been previously considered.In conclusion,the T.gondii RH strain could promote and mediate apoptosis through multiple pathways mentioned above in Vero cells.Our findings improve the understanding of the T.gondii infection process through providing new insights into the related cellular apoptosis mechanisms.
基金National Natural Science Foundation of China,No. 30700773,No. 81070378,and No. 81270561Sichuan Outstanding Youth Fund Project,No. 2015JQ0060。
文摘BACKGROUND Long non-coding RNAs(lncRNAs) have been shown to be associated with many tumors. However, the specific mechanism of lncRNAs in the occurrence and development of gastric cancer(GC) has not been fully elucidated.AIM To explore the expression level and molecular mechanism of HOXD-AS2 in GC tissues and cells, and analyze its significance in the prognosis of GC.METHODS Real-time quantitative PCR was used to detect the expression of HOXD-AS2 in 79 pairs of GC tissues and five cell lines. The pc HOXD-AS2 plasmid vector was constructed and transfected into SGC-7901 and SNU-1 GC cells. Matrigel Transwell and wound healing assays were used to confirm the effect of HOXDAS2 on invasion and migration of GC cells. Cell counting kit-8 assay and flow cytometry were used to verify the effect of HOXD-AS2 on the proliferation, cell cycle, and apoptosis of GC cells. The relevant regulatory mechanism between HOXD-AS2 and HOXD8 and PI3K/Akt signaling pathway was verified by Western blot analysis.RESULTS The low expression of lncRNA HOXD-AS2 was associated with lymph node metastasis and tumor-node-metastasis stage in GC. In vitro functional experiments demonstrated that overexpression of HOXD-AS2 inhibited GC cell progression. Mechanistic studies revealed that HOXD-AS2 regulated the expression of its nearby gene HOXD8 and inhibited the activity of the PI3K/Akt signaling pathway.CONCLUSION These results indicate that downregulation of HOXD-AS2 significantly promotes the progression of GC cells by regulating HOXD8 expression and activating the PI3K/Akt signaling pathway. HOXD-AS2 may be a novel diagnostic biomarker and effective therapeutic target for GC.
基金supported by the National Key Research and Development Program of China(Nos.2016YFA0400502,2018YFA0404404)the National Natural Science Foundation of China(Nos.U1867211,11490563,12005304,12125509,11961141003 and U1332129)。
文摘The response functions of a 4π summing BGO detector were established using extensive experimental measurements and GEANT4 simulation. The partial and total efficiencies for all components of the γ-ray interaction with the BGO detector were also measured. These response functions and efficiencies will be used in the β-Oslo method experiments to study the neutron capture cross sections of radioactive heavy ions. The application of the response functions of the BGO detector under simulated continuum γ-rays and source measurement γ-rays proves that the method and response functions are reliable.
基金This work was supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24010104-2).
文摘Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.
