Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environ...Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and cost-effectiveness.However,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low utilization.Thus,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is reported.The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition.The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.展开更多
Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system(IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term ...Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system(IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term memory(LSTM)and multiple load forecasting errors.This strategy dynamically selects a hybrid timescale which is suitable for a variety of energies for each month.This is obtained by combining the mean absolute percentage error(MAPE)curve of the load forecasting with the error restriction requirements of the dispatcher.Based on the day-ahead scheduling plan,the output of the partial equipment is selectively adjusted at each time-scale to realize multi-energy collaborative optimization and gives full play to the comprehensive advantages of the IES.This is achieved by considering the differences in the response speed for each piece of equipment within the intra-day scheduling.This study uses the IES as an example,and it dynamically determines the time scale of the energy monthly.In addition,this investigation presents a detailed analysis of the output plan of the key equipment to demonstrate the necessity and the advantages of the strategy.展开更多
Rice(Oryza sativa L.)is a major food crop worldwide.Plant height and yield are important agronomic traits of rice.Several genes regulating plant height and/or yield have been cloned.However,the molecular mechanisms co...Rice(Oryza sativa L.)is a major food crop worldwide.Plant height and yield are important agronomic traits of rice.Several genes regulating plant height and/or yield have been cloned.However,the molecular mechanisms coordinating plant height and yield are not fully characterized.Here,we report a novel gene,OstMAPKKK5 that encodes a truncated variant of a mitogen-activated protein kinase kinase kinase 5(OsMAPKKK5)lacking an intact kinase domain.Transgenic plants overexpressing OstMAPKKK5 in indica cultivar 9311 showed increased plant height,grain length,grain width,1000-grain weight,grain number per main panicle,and yield.Real-time quantitative PCR showed that OstMAPKKK5 was widely expressed in various tissues and developmental stages.The increased plant height and yield were attributed to enlarged cell size.Overexpression of OstMAPKKK5 led to higher contents of various forms of endogenous gibberellin(GA),especially the most common active forms,GA1,GA3,GA4.We concluded that OstMAPKKK5 positively regulates plant height and yield in rice by affecting cell size,and that its underlying mechanism is based on increased endogenous GA content.展开更多
To fully exploit the rich characteristic variation laws of an integrated energy system(IES)and further improve the short-term load-forecasting accuracy,a load-forecasting method is proposed for an IES based on LSTM an...To fully exploit the rich characteristic variation laws of an integrated energy system(IES)and further improve the short-term load-forecasting accuracy,a load-forecasting method is proposed for an IES based on LSTM and dynamic similar days with multi-features.Feature expansion was performed to construct a comprehensive load day covering the load and meteorological information with coarse and fine time granularity,far and near time periods.The Gaussian mixture model(GMM)was used to divide the scene of the comprehensive load day,and gray correlation analysis was used to match the scene with the coarse time granularity characteristics of the day to be forecasted.Five typical days with the highest correlation with the day to be predicted in the scene were selected to construct a“dynamic similar day”by weighting.The key features of adjacent days and dynamic similar days were used to forecast multi-loads with fine time granularity using LSTM.Comparing the static features as input and the selection method of similar days based on non-extended single features,the effectiveness of the proposed prediction method was verified.展开更多
The structure of the primary olfactory brain center was studied in male and female adult Ambrostoma quadriimpressum by means of a series of histological sections labeled using the reduced-silver-stain technique.The an...The structure of the primary olfactory brain center was studied in male and female adult Ambrostoma quadriimpressum by means of a series of histological sections labeled using the reduced-silver-stain technique.The antennal lobe was elliptical,and the total number of glomeruli was approximately 50 in the antennal lobe in both sexes.There was no sexual dimorphism with respect to the size of the antennal lobe or the number and shape of glomeruli.展开更多
In the arid region of northwestern China(ARNC),water resources are the most critical factor restricting socioeconomic development and influencing the stability of the area’s ecological systems.The region’s complex w...In the arid region of northwestern China(ARNC),water resources are the most critical factor restricting socioeconomic development and influencing the stability of the area’s ecological systems.The region’s complex water system and unique hydrological cycle show distinctive characteristics.Moreover,the intensified hydrological cycle and extreme climatic and hydrological events resulting from global warming have led to increased uncertainty around water resources as well as heightened conflict between water supply and water demand.All of these factors are exerting growing pressures on the socioeconomic development and vulnerable ecological environment in the region.This research evaluates the impacts of climate change on water resources,hydrological processes,agricultural system,and desert ecosystems in the ARNC,and addresses some associated risks and challenges specific to this area.The temperature is rising at a rate of 0.31C per decade during 1961–2017 and hydrological processes are being significantly influenced by changes in glaciers,snow cover,and precipitation form,especially in the rivers recharged primarily by melt water.Ecosystems are also largely influenced by climate change,with the Normalized Difference Vegetation Index(NDVI)of natural vegetation exhibited an increasing trend prior to 1998,and then reversed in Xinjiang while the Hexi Corridor of Gansu showed the opposite trends.Furthermore,the desert-oasis transition zone showed a reduction in area due to the warming trend and the recent rapid expansion of irrigated area.Both the warming and intensified drought are threatening agriculture security.The present study could shed light on sustainable development in this region under climate change and provides scientific basis to the construction of the“Silk Road Economic Belt”.展开更多
This paper reviewed advances in researches on genetic diversity of Lepidoptera insects from chromosome polymorphism,protein polymorphism,and DNA polymorphism,and stated that DNA sequence variation will become main poi...This paper reviewed advances in researches on genetic diversity of Lepidoptera insects from chromosome polymorphism,protein polymorphism,and DNA polymorphism,and stated that DNA sequence variation will become main points of researches about genetic diversity.展开更多
Frontal upwelling is an important phenomenon in summer in the Yellow Sea(YS)and plays an essential role in the distribution of nutrients and biological species.In this paper,a three-dimensional hydrodynamic model is a...Frontal upwelling is an important phenomenon in summer in the Yellow Sea(YS)and plays an essential role in the distribution of nutrients and biological species.In this paper,a three-dimensional hydrodynamic model is applied to investigate the characteristics and influencing factors of frontal upwelling in the YS.The results show that the strength and distribution of frontal upwelling are largely dependent on the topography and bottom temperature fronts.The frontal upwelling in the YS is stronger and narrower near the eastern coast than near the western coast due to the steeper shelf slope.Moreover,external forcings,such as the meridional wind speed and air temperature in summer and the air temperature in the preceding winter and spring,have certain influences on the strength of frontal upwelling.An increase in air temperature in the previous winter and spring weakens the frontal upwelling in summer;in contrast,an increase in air temperature in summer strengthens the frontal upwelling.When the southerly wind in summer increases,the upwelling intensifies in the western YS and weakens in the eastern YS.The air temperature influences the strength of upwelling by changing the baroclinicity in the frontal region.Furthermore,the meridional wind speed in summer affects frontal upwelling via Ekman pumping.展开更多
Memristor has been widely studied in the field of neuromorphic computing and is considered to be a strong candidate to break the von Neumann bottleneck. However, the non-ideal characteristics of memristor seriously li...Memristor has been widely studied in the field of neuromorphic computing and is considered to be a strong candidate to break the von Neumann bottleneck. However, the non-ideal characteristics of memristor seriously limit its practical application. There are two sides to everything, and memristors are no exception. The non-ideal characteristics of memristors may become ideal in some applications. Genetic algorithm(GA) is a method to search for the optimal solution by simulating the process of biological evolution. It is widely used in the fields of machine learning, combinatorial optimization,and signal processing. In this paper, we simulate the biological evolutionary behavior in GA by using the non-ideal characteristics of memristors, based on which we design peripheral circuits and path planning algorithms based on memristor networks. The experimental results show that the non-ideal characteristics of memristor can well simulate the biological evolution behavior in GA.展开更多
In recent years, spiking neural networks(SNNs) have received increasing attention of research in the field of artificial intelligence due to their high biological plausibility, low energy consumption, and abundant spa...In recent years, spiking neural networks(SNNs) have received increasing attention of research in the field of artificial intelligence due to their high biological plausibility, low energy consumption, and abundant spatio-temporal information.However, the non-differential spike activity makes SNNs more difficult to train in supervised training. Most existing methods focusing on introducing an approximated derivative to replace it, while they are often based on static surrogate functions. In this paper, we propose a progressive surrogate gradient learning for backpropagation of SNNs, which is able to approximate the step function gradually and to reduce information loss. Furthermore, memristor cross arrays are used for speeding up calculation and reducing system energy consumption for their hardware advantage. The proposed algorithm is evaluated on both static and neuromorphic datasets using fully connected and convolutional network architecture, and the experimental results indicate that our approach has a high performance compared with previous research.展开更多
Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium,the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a flu...Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium,the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a fluidstructure interaction model for the interaction between coal gas and coal-rock masses.The outburst process in coal-rock masses under the joint action of gas pressure and crustal stress is simulated using the material point method.The simulation results show the changes in gas pressure,velocity distribution,maximum principal stress distribution,and damage distribution during the process of the coal and gas outburst,as well as themovement and accumulation of coal-rock masses after the occurrence of the outburst.It was found that the gas pressure gradient was greatest at theworking face after the occurrence of the outburst,the gas pressures and pressure gradients at each location within the coal seamgradually decreased with time,and the damage distribution was essentially the same as the minimum principal stress distribution.The simulation further revealed that the outburst first occurred in themiddle of the tunnel excavation face and that the speed at which particles of coal mass were ejected was highest at the center and decreased toward the upper and lower sides.The study provides a scientific basis for enhancing our understanding of the mechanism behind coal and gas outbursts,as well as their prevention and control.展开更多
Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.H...Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.Here,we identified UAT-B,a novel neoantimycin analog isolated from Streptomyces conglobatus,as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction(PPI)to overcome multi-drug resistance in colorectal cancer(CRC).The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels,triggering cell apoptosis through modulation of the Wnt/β-catenin pathway.Importantly,UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels,as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts,as well as APC^(min/+)spontaneous CRC models.Collectively,these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment,and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.展开更多
Woody plants in forests play a central role in sustaining ecosystem function and serve as renewable sources of energy.Perennial trees in temperate and boreal regions exhibit seasonally synchronized shoot growth and wo...Woody plants in forests play a central role in sustaining ecosystem function and serve as renewable sources of energy.Perennial trees in temperate and boreal regions exhibit seasonally synchronized shoot growth and wood production,as revealed by bud growth-dormancy cycles and tree-ring formation.To survive harsh winters,trees undergo vegetative growth cessation in late summer or early autumn,impacting the duration of wood production and wood quality.However,deciduous trees in frost-free temperate and subtropical regions may experience limited atmospheric carbon assimilation and biomass accumulation due to seasonal dormancy.Thus,understanding the regulatory networks governing the seasonal growth of trees could facilitate the generation of desirable tree germplasm suited for different climate zones.展开更多
目的探讨探讨腹腔镜脾切除术(LS)治疗外伤性脾破裂(TSR)的疗效及体会。方法回顾性分析2013年1月至2018年8月在中山大学附属第三医院粤东医院行手术治疗的27例TSR患者临床资料。患者均签署知情同意书,符合医学伦理学规定。其中男19例,女8...目的探讨探讨腹腔镜脾切除术(LS)治疗外伤性脾破裂(TSR)的疗效及体会。方法回顾性分析2013年1月至2018年8月在中山大学附属第三医院粤东医院行手术治疗的27例TSR患者临床资料。患者均签署知情同意书,符合医学伦理学规定。其中男19例,女8例;平均年龄(43±16)岁。车祸伤19例,坠落伤6例,其他外伤2例。根据脾损伤分级,Ⅰ级损伤1例,Ⅱ级损伤2例,Ⅲ级损伤17例,Ⅳ级损伤7例。根据手术方式将患者分为腔镜组(12例)和开腹组(15例)。观察两组患者围手术期情况。两组术中出血量、术后24 h视觉模拟评分法(VAS)评分等比较采用t检验。结果腹腔镜1例因术中出血无法控制,中转开腹手术。其余患者手术均顺利完成。腔镜组术中出血量、术后24 h VAS评分、术后首次肛门排气时间和术后首次下床时间分别为(157±50)ml、(3.6±1.8)分、(2.8±0.7)d、(2.2±0.6)d,明显少于开腹组的(209±71)ml、(4.7±1.5)分、(3.5±0.9)d、(2.9±0.9)d(t=-2.166,-1.828,-2.126,-2.573;P<0.05)。两组患者均无发生死亡,无血栓形成。腔镜组出现发热1例,予吲哚美辛治疗5 d痊愈。开腹组切口感染2例,肺部感染1例,予换药和抗感染后治愈。结论与传统开腹脾切除术相比,LS治疗TSR可减少术中出血量、减轻术后疼痛,具有损伤小、恢复快的优势。展开更多
A thorough understanding of the genetic basis of rice grain traits is critical for the improvement of rice （Oryza sativa L.） varieties. In this study, we generated an F2 population by crossing the large-grain japoni...A thorough understanding of the genetic basis of rice grain traits is critical for the improvement of rice （Oryza sativa L.） varieties. In this study, we generated an F2 population by crossing the large-grain japonica cultivar CW23 with Peiai 64 （PA64）, an elite indica small-grain cultivar. Using QTL analysis, 17 QTLs for five grain traits were detected on four different chromosomes. Eight of the QTLs were newly-identified in this study. In particular, qGL3-1, a newly-identified grain length QTL with the highest LOD value and largest phenotypic variation, was fine-mapped to the 17 kb region of chromosome 3. A serine/threonine protein phosphatase gene encoding a repeat domain containing two Kelch motifs was identified as the unique candidate gene corresponding to this QTL. A comparison of PA64 and CW23 sequences revealed a single nucleotide substitution （C→A） at position 1092 in exon 10, resulting in replacement of Asp （D） in PA64 with Glu （E） in CW23 for the 364th amino acid. This variation is located at the D position of the conserved sequence motif AVLDT of the Kelch repeat. Genetic analysis of a near-isogenic line （NIL） for qGL3-1 revealed that the allele qGL3-1 from CW23 has an additive or partly dominant effect, and is suitable for use in molecular marker-assisted selection.展开更多
Calcium-magnesium-alumino-silicate(CMAS)corrosion is a critical factor which causes the failure of thermal barrier coating(TBC).CMAS attack significantly alters the temperature and stress fields in TBC,resulting in th...Calcium-magnesium-alumino-silicate(CMAS)corrosion is a critical factor which causes the failure of thermal barrier coating(TBC).CMAS attack significantly alters the temperature and stress fields in TBC,resulting in their delamination or spallation.In this work,the evolution process of TBC prepared by suspension plasma spraying(SPS)under CMAS attack is investigated.The CMAS corrosion leads to the formation of the reaction layer and subsequent bending of TBC.Based on the observations,a corrosion model is proposed to describe the generation and evolution of the reaction layer and bending of TBC.Then,numerical simulations are performed to investigate the corrosion process of free-standing TBC and the complete TBC system under CMAS attack.The corrosion model constructs a bridge for connecting two numerical models.The results show that the CMAS corrosion has a significant influence on the stress field,such as the peak stress,whereas it has little influence on the steady-state temperature field.The peak of stress increases with holding time,which increases the risk of the rupture of TBC.The Mises stress increases nonlinearly along the thick direction of the reaction layer.Furthermore,in the traditional failure zone,such as the interface of the top coat and bond coat,the stress obviously changes during CMAS corrosion.展开更多
基金the China Scholarship Council(CSC)for funding(no.201806310116)。
文摘Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and cost-effectiveness.However,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low utilization.Thus,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is reported.The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition.The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.
基金supported by the Fundamental Research Funds for the Central Universities(No.2017MS093)
文摘Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system(IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term memory(LSTM)and multiple load forecasting errors.This strategy dynamically selects a hybrid timescale which is suitable for a variety of energies for each month.This is obtained by combining the mean absolute percentage error(MAPE)curve of the load forecasting with the error restriction requirements of the dispatcher.Based on the day-ahead scheduling plan,the output of the partial equipment is selectively adjusted at each time-scale to realize multi-energy collaborative optimization and gives full play to the comprehensive advantages of the IES.This is achieved by considering the differences in the response speed for each piece of equipment within the intra-day scheduling.This study uses the IES as an example,and it dynamically determines the time scale of the energy monthly.In addition,this investigation presents a detailed analysis of the output plan of the key equipment to demonstrate the necessity and the advantages of the strategy.
基金supported by the National Natural Science Foundation of China (31471461, 31671655)the National Transgenic Major Project of China (2016ZX08001004-001)Shanghai Agriculture Applied Technology Development Program, China (G2014070102)
文摘Rice(Oryza sativa L.)is a major food crop worldwide.Plant height and yield are important agronomic traits of rice.Several genes regulating plant height and/or yield have been cloned.However,the molecular mechanisms coordinating plant height and yield are not fully characterized.Here,we report a novel gene,OstMAPKKK5 that encodes a truncated variant of a mitogen-activated protein kinase kinase kinase 5(OsMAPKKK5)lacking an intact kinase domain.Transgenic plants overexpressing OstMAPKKK5 in indica cultivar 9311 showed increased plant height,grain length,grain width,1000-grain weight,grain number per main panicle,and yield.Real-time quantitative PCR showed that OstMAPKKK5 was widely expressed in various tissues and developmental stages.The increased plant height and yield were attributed to enlarged cell size.Overexpression of OstMAPKKK5 led to higher contents of various forms of endogenous gibberellin(GA),especially the most common active forms,GA1,GA3,GA4.We concluded that OstMAPKKK5 positively regulates plant height and yield in rice by affecting cell size,and that its underlying mechanism is based on increased endogenous GA content.
基金supported by National Natural Science Foundation of China(NSFC)(62103126).
文摘To fully exploit the rich characteristic variation laws of an integrated energy system(IES)and further improve the short-term load-forecasting accuracy,a load-forecasting method is proposed for an IES based on LSTM and dynamic similar days with multi-features.Feature expansion was performed to construct a comprehensive load day covering the load and meteorological information with coarse and fine time granularity,far and near time periods.The Gaussian mixture model(GMM)was used to divide the scene of the comprehensive load day,and gray correlation analysis was used to match the scene with the coarse time granularity characteristics of the day to be forecasted.Five typical days with the highest correlation with the day to be predicted in the scene were selected to construct a“dynamic similar day”by weighting.The key features of adjacent days and dynamic similar days were used to forecast multi-loads with fine time granularity using LSTM.Comparing the static features as input and the selection method of similar days based on non-extended single features,the effectiveness of the proposed prediction method was verified.
基金This research was supported by the Natural Science Foundation of China Heilongjiang(C2017059).
文摘The structure of the primary olfactory brain center was studied in male and female adult Ambrostoma quadriimpressum by means of a series of histological sections labeled using the reduced-silver-stain technique.The antennal lobe was elliptical,and the total number of glomeruli was approximately 50 in the antennal lobe in both sexes.There was no sexual dimorphism with respect to the size of the antennal lobe or the number and shape of glomeruli.
基金supported by the National Key Research and Development Program(2019YFA0606902)the National Natural Science Foundation of China(U1903208)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2019431).
文摘In the arid region of northwestern China(ARNC),water resources are the most critical factor restricting socioeconomic development and influencing the stability of the area’s ecological systems.The region’s complex water system and unique hydrological cycle show distinctive characteristics.Moreover,the intensified hydrological cycle and extreme climatic and hydrological events resulting from global warming have led to increased uncertainty around water resources as well as heightened conflict between water supply and water demand.All of these factors are exerting growing pressures on the socioeconomic development and vulnerable ecological environment in the region.This research evaluates the impacts of climate change on water resources,hydrological processes,agricultural system,and desert ecosystems in the ARNC,and addresses some associated risks and challenges specific to this area.The temperature is rising at a rate of 0.31C per decade during 1961–2017 and hydrological processes are being significantly influenced by changes in glaciers,snow cover,and precipitation form,especially in the rivers recharged primarily by melt water.Ecosystems are also largely influenced by climate change,with the Normalized Difference Vegetation Index(NDVI)of natural vegetation exhibited an increasing trend prior to 1998,and then reversed in Xinjiang while the Hexi Corridor of Gansu showed the opposite trends.Furthermore,the desert-oasis transition zone showed a reduction in area due to the warming trend and the recent rapid expansion of irrigated area.Both the warming and intensified drought are threatening agriculture security.The present study could shed light on sustainable development in this region under climate change and provides scientific basis to the construction of the“Silk Road Economic Belt”.
基金Supported by Special Fund Project for Talent Development of Anhui Academy of Agricultural Sciences(17F0610)Discipline Construction Project of Anhui Academy of Agricultural Sciences(16A0618)Project of Hefei Comprehensive Experiment Station of China Sericulture Industry Technology System(CARS-22-SYZ09)
文摘This paper reviewed advances in researches on genetic diversity of Lepidoptera insects from chromosome polymorphism,protein polymorphism,and DNA polymorphism,and stated that DNA sequence variation will become main points of researches about genetic diversity.
基金The National Key Research and Development Project under contract No.2017YFC1403400the National Key Research and Development Program of China under contract No.2016YFC1402501+2 种基金the National Natural Science Foundation of China under contract No.41806164the Open Fund Project of Key Laboratory of Marine Environmental Information Technology,Ministry of Natural Resourcesthe Shandong Joint Fund for Marine Science Research Centers under contract No.U1406401.
文摘Frontal upwelling is an important phenomenon in summer in the Yellow Sea(YS)and plays an essential role in the distribution of nutrients and biological species.In this paper,a three-dimensional hydrodynamic model is applied to investigate the characteristics and influencing factors of frontal upwelling in the YS.The results show that the strength and distribution of frontal upwelling are largely dependent on the topography and bottom temperature fronts.The frontal upwelling in the YS is stronger and narrower near the eastern coast than near the western coast due to the steeper shelf slope.Moreover,external forcings,such as the meridional wind speed and air temperature in summer and the air temperature in the preceding winter and spring,have certain influences on the strength of frontal upwelling.An increase in air temperature in the previous winter and spring weakens the frontal upwelling in summer;in contrast,an increase in air temperature in summer strengthens the frontal upwelling.When the southerly wind in summer increases,the upwelling intensifies in the western YS and weakens in the eastern YS.The air temperature influences the strength of upwelling by changing the baroclinicity in the frontal region.Furthermore,the meridional wind speed in summer affects frontal upwelling via Ekman pumping.
基金supported by the National Natural Science Foundation of China (Grant Nos. 61976246 and U20A20227)the Natural Science Foundation of Chongqing, China (Grant No. cstc2020jcyj-msxm X0385)the National Key R&D Program of China (Grant Nos. 2018YFB130660 and 2018YFB1306604)。
文摘Memristor has been widely studied in the field of neuromorphic computing and is considered to be a strong candidate to break the von Neumann bottleneck. However, the non-ideal characteristics of memristor seriously limit its practical application. There are two sides to everything, and memristors are no exception. The non-ideal characteristics of memristors may become ideal in some applications. Genetic algorithm(GA) is a method to search for the optimal solution by simulating the process of biological evolution. It is widely used in the fields of machine learning, combinatorial optimization,and signal processing. In this paper, we simulate the biological evolutionary behavior in GA by using the non-ideal characteristics of memristors, based on which we design peripheral circuits and path planning algorithms based on memristor networks. The experimental results show that the non-ideal characteristics of memristor can well simulate the biological evolution behavior in GA.
基金Project supported by the Natural Science Foundation of Chongqing(Grant No.cstc2021jcyj-msxmX0565)the Fundamental Research Funds for the Central Universities(Grant No.SWU021002)the Graduate Research Innovation Project of Chongqing(Grant No.CYS22242)。
文摘In recent years, spiking neural networks(SNNs) have received increasing attention of research in the field of artificial intelligence due to their high biological plausibility, low energy consumption, and abundant spatio-temporal information.However, the non-differential spike activity makes SNNs more difficult to train in supervised training. Most existing methods focusing on introducing an approximated derivative to replace it, while they are often based on static surrogate functions. In this paper, we propose a progressive surrogate gradient learning for backpropagation of SNNs, which is able to approximate the step function gradually and to reduce information loss. Furthermore, memristor cross arrays are used for speeding up calculation and reducing system energy consumption for their hardware advantage. The proposed algorithm is evaluated on both static and neuromorphic datasets using fully connected and convolutional network architecture, and the experimental results indicate that our approach has a high performance compared with previous research.
基金The article received China National Natural Science Found(41601574).
文摘Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium,the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a fluidstructure interaction model for the interaction between coal gas and coal-rock masses.The outburst process in coal-rock masses under the joint action of gas pressure and crustal stress is simulated using the material point method.The simulation results show the changes in gas pressure,velocity distribution,maximum principal stress distribution,and damage distribution during the process of the coal and gas outburst,as well as themovement and accumulation of coal-rock masses after the occurrence of the outburst.It was found that the gas pressure gradient was greatest at theworking face after the occurrence of the outburst,the gas pressures and pressure gradients at each location within the coal seamgradually decreased with time,and the damage distribution was essentially the same as the minimum principal stress distribution.The simulation further revealed that the outburst first occurred in themiddle of the tunnel excavation face and that the speed at which particles of coal mass were ejected was highest at the center and decreased toward the upper and lower sides.The study provides a scientific basis for enhancing our understanding of the mechanism behind coal and gas outbursts,as well as their prevention and control.
基金This study was financially supported by the National Key Research and Development Program of China(2022YFC2804100,2021YFF0502400,2022YFC2804300)National Natural Science Foundation of China(82073713,22137006,82104033,82173730,81903499,32070070,82160669)Innovative research team of highlevel local universities in Shanghai(SHSMU-ZDCX20212702,China).We thank Dr.Juncheng Su from Shanghai Jiao-Tong University School of Medicine(Shanghai,China)for providing the LoVo and COLO 320DM cell lines.
文摘Modulating Tankyrases(TNKS),interactions with USP25 to promote TNKS degradation,rather than inhibiting their enzymatic activities,is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway.Here,we identified UAT-B,a novel neoantimycin analog isolated from Streptomyces conglobatus,as a small-molecule inhibitor of TNKS-USP25 protein-protein interaction(PPI)to overcome multi-drug resistance in colorectal cancer(CRC).The disruption of TNKS-USP25 complex formation by UAT-B led to a significant decrease in TNKS levels,triggering cell apoptosis through modulation of the Wnt/β-catenin pathway.Importantly,UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels,as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts,as well as APC^(min/+)spontaneous CRC models.Collectively,these findings suggest that targeting the TNKS-USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment,and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.
基金supported by the Biological Breeding-National Science and Technology Major Project(2023ZD04068)Natural Science Foundation Project of CQ CSTC(cstc2021jcyj-msxmX0995)Fundamental Research Funds for the Central Universities(SWUKR22015)。
文摘Woody plants in forests play a central role in sustaining ecosystem function and serve as renewable sources of energy.Perennial trees in temperate and boreal regions exhibit seasonally synchronized shoot growth and wood production,as revealed by bud growth-dormancy cycles and tree-ring formation.To survive harsh winters,trees undergo vegetative growth cessation in late summer or early autumn,impacting the duration of wood production and wood quality.However,deciduous trees in frost-free temperate and subtropical regions may experience limited atmospheric carbon assimilation and biomass accumulation due to seasonal dormancy.Thus,understanding the regulatory networks governing the seasonal growth of trees could facilitate the generation of desirable tree germplasm suited for different climate zones.
文摘目的探讨探讨腹腔镜脾切除术(LS)治疗外伤性脾破裂(TSR)的疗效及体会。方法回顾性分析2013年1月至2018年8月在中山大学附属第三医院粤东医院行手术治疗的27例TSR患者临床资料。患者均签署知情同意书,符合医学伦理学规定。其中男19例,女8例;平均年龄(43±16)岁。车祸伤19例,坠落伤6例,其他外伤2例。根据脾损伤分级,Ⅰ级损伤1例,Ⅱ级损伤2例,Ⅲ级损伤17例,Ⅳ级损伤7例。根据手术方式将患者分为腔镜组(12例)和开腹组(15例)。观察两组患者围手术期情况。两组术中出血量、术后24 h视觉模拟评分法(VAS)评分等比较采用t检验。结果腹腔镜1例因术中出血无法控制,中转开腹手术。其余患者手术均顺利完成。腔镜组术中出血量、术后24 h VAS评分、术后首次肛门排气时间和术后首次下床时间分别为(157±50)ml、(3.6±1.8)分、(2.8±0.7)d、(2.2±0.6)d,明显少于开腹组的(209±71)ml、(4.7±1.5)分、(3.5±0.9)d、(2.9±0.9)d(t=-2.166,-1.828,-2.126,-2.573;P<0.05)。两组患者均无发生死亡,无血栓形成。腔镜组出现发热1例,予吲哚美辛治疗5 d痊愈。开腹组切口感染2例,肺部感染1例,予换药和抗感染后治愈。结论与传统开腹脾切除术相比,LS治疗TSR可减少术中出血量、减轻术后疼痛,具有损伤小、恢复快的优势。
基金supported by grants from the Geneti-cally Modified Organisms Breeding Major Projects of China(2011ZX08001-004-009)the National Natural Science Foun-dation of China(30900881)+2 种基金the Jiangxi Province Major Science and Technology Projects and Super Hybrid Rice BreedingDemonstration and Dissemination Projects(20114ABF03105)the Natural Science Foundation of Shandong Province(Y2006D22)
文摘A thorough understanding of the genetic basis of rice grain traits is critical for the improvement of rice （Oryza sativa L.） varieties. In this study, we generated an F2 population by crossing the large-grain japonica cultivar CW23 with Peiai 64 （PA64）, an elite indica small-grain cultivar. Using QTL analysis, 17 QTLs for five grain traits were detected on four different chromosomes. Eight of the QTLs were newly-identified in this study. In particular, qGL3-1, a newly-identified grain length QTL with the highest LOD value and largest phenotypic variation, was fine-mapped to the 17 kb region of chromosome 3. A serine/threonine protein phosphatase gene encoding a repeat domain containing two Kelch motifs was identified as the unique candidate gene corresponding to this QTL. A comparison of PA64 and CW23 sequences revealed a single nucleotide substitution （C→A） at position 1092 in exon 10, resulting in replacement of Asp （D） in PA64 with Glu （E） in CW23 for the 364th amino acid. This variation is located at the D position of the conserved sequence motif AVLDT of the Kelch repeat. Genetic analysis of a near-isogenic line （NIL） for qGL3-1 revealed that the allele qGL3-1 from CW23 has an additive or partly dominant effect, and is suitable for use in molecular marker-assisted selection.
基金This study is supported by the National Natural Science Foundation of China(Nos.1171101165 and 11902240).
文摘Calcium-magnesium-alumino-silicate(CMAS)corrosion is a critical factor which causes the failure of thermal barrier coating(TBC).CMAS attack significantly alters the temperature and stress fields in TBC,resulting in their delamination or spallation.In this work,the evolution process of TBC prepared by suspension plasma spraying(SPS)under CMAS attack is investigated.The CMAS corrosion leads to the formation of the reaction layer and subsequent bending of TBC.Based on the observations,a corrosion model is proposed to describe the generation and evolution of the reaction layer and bending of TBC.Then,numerical simulations are performed to investigate the corrosion process of free-standing TBC and the complete TBC system under CMAS attack.The corrosion model constructs a bridge for connecting two numerical models.The results show that the CMAS corrosion has a significant influence on the stress field,such as the peak stress,whereas it has little influence on the steady-state temperature field.The peak of stress increases with holding time,which increases the risk of the rupture of TBC.The Mises stress increases nonlinearly along the thick direction of the reaction layer.Furthermore,in the traditional failure zone,such as the interface of the top coat and bond coat,the stress obviously changes during CMAS corrosion.
