Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee...Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields.展开更多
The lamellar microstructure is one of the most typical microstructures of TiAl alloys.There are threeγ/γinterfaces with different microstructures in lamellarγ-TiAl alloys.In this work,we investigated the deformatio...The lamellar microstructure is one of the most typical microstructures of TiAl alloys.There are threeγ/γinterfaces with different microstructures in lamellarγ-TiAl alloys.In this work,we investigated the deformation processes of lamellarγ-TiAl alloys with different interfacial spacing(λ)via uniaxial tensile loading using molecular dynamics simulations,including true twin(TT),pseudo-twin(PT),rotational boundary(RB),and the mixed structure(TT∥PT∥RB).The results show that in all lamellarγ-TiAl samples,the Shockley partial dislocation prefers to nucleate in the region between two neighboring interfaces.Then,dislocations move towards,crossing theγ/γinterface.Finally,the dislocation slippage leads to the destruction of the interface,resulting in cracks and structural failure.With the decrease ofλ,the ultimate strength slightly increases in the TT or PT structure ofγ-TiAl,which follows the Hall-Petch relation.But in general,the interfacial spacing has a slight effect on the ultimate strengths of these four structures ofγ-TiAl.展开更多
Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet...Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet it is unknown how these croplands will respond to climate change.Here,using yield statistics from 1985 to 2015,we found that the impact of temperature anomalies on the Tibetan crop yield shifted from nonsignificant(P>0.10)in the 1980s and 1990s to significantly negative(P<0.05)in recent years.Meanwhile,the apparent sensitivity of the crop yield to temperature anomalies almost doubled,from(–0.13±0.20)to(–0.22±0.14)t·ha^(-1)℃^(–1).The emerging negative impacts of higher temperatures suggest an increasing vulnerability of Tibetan croplands to warmer climate.With global warming scenarios of+1.5 or+2.0℃above the pre-industry level,the temperature sensitivities of crop yield may further increase to(–0.33±0.10)and(–0.51±0.18)t·ha^(-1)℃^(–1),respectively,making the crops 2–3 times more vulnerable to warmer temperatures than they are today.展开更多
Dear Editor,This letter proposes a contrastive consensus graph learning model for multi-view clustering.Graphs are usually built to outline the correlation between multi-model objects in clustering task,and multiview ...Dear Editor,This letter proposes a contrastive consensus graph learning model for multi-view clustering.Graphs are usually built to outline the correlation between multi-model objects in clustering task,and multiview graph clustering aims to learn a consensus graph that integrates the spatial property of each view.展开更多
The low frequency load of an underwater explosion bubble and the generated waves can cause significant rigid motion of a ship that threaten its stability.In order to study the fluid-structure interaction qualitatively...The low frequency load of an underwater explosion bubble and the generated waves can cause significant rigid motion of a ship that threaten its stability.In order to study the fluid-structure interaction qualitatively,a two-dimensional underwater explosion bubble dynamics model,based on the potential flow theory,is established with a double-vortex model for the doubly connected bubble dynamics simulation,and the bubble shows similar dynamics to that in 3-dimensional domain.A fully nonlinear fluid-structure interaction model is established considering the rigid motion of the floating body using the mode-decomposition method.Convergence test of the model is implemented by simulating the free rolling motion of a floating body in still water.Through the simulation of the interaction of the underwater explosion bubble,the generated waves and the floating body based on the presented model,the influences of the buoyancy parameter and the distance parameter are discussed.It is found that the impact loads on floating body caused by underwater explosion bubble near the free surface can be divided into 3 components:bubble pulsation,jet impact,and slamming load of the generated waves,and the intensity of each component changes nonlinearly with the buoyance parameter.The bubble pulsation load decays with the increase in the horizontal distance.However,the impact load from the generated waves is not monotonous to distance.It increases with the distance within a particular distance threshold,but decays thereafter.展开更多
Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau.However,it is unclear whether fencing reduces CO_(2),CH_4,and N_2O emission.Here,w...Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau.However,it is unclear whether fencing reduces CO_(2),CH_4,and N_2O emission.Here,we selected four vegetation types of alpine meadow(graminoid,shrub,forb,and sparse vegetation)to determine fencing effects on ecosystem respiration(Re),CH_4,and N_2O fluxes during the growing season.Despite increased average monthly ecosystem respiration(Re)for fenced graminoid vegetation at the end of the growing season,there was no significant difference between grazing and fencing across all vegetation types.Fencing significantly reduced average CH_4 uptake by about 50%in 2008 only for forb vegetation and increased average N_2O release for graminoid vegetation by 38%and 48%in 2008 and 2009,respectively.Temperature,moisture,total organic carbon,C/N,nitrate,ammonia,and/or bulk density of soil,as well as above-and belowground biomass,explained 19%~71%and 6%~33%of variation in daily and average Re and CH_4 fluxes across all vegetation types,while soil-bulk density explained 27%of variation in average N_2O fluxes.Stepwise regression showed that soil temperature and soil moisture controlled average Re,while soil moisture and bulk density controlled average CH_4 fluxes.These results indicate that abiotic factors control Re,CH_4,and N_2O fluxes;and grazing exclusion has little effect on reducing their emission—implying that climatic change rather than grazing may have a more important influence on the budgets of Re and CH_4 for the Tibetan alpine meadow during the growing season.展开更多
Prunus pusilliflora is a wild cherry germplasm resource distributed mainly in Southwest China.Despite its ornamental and economic value,a high-quality assembled P.pusilliflora genome is unavailable,hindering our under...Prunus pusilliflora is a wild cherry germplasm resource distributed mainly in Southwest China.Despite its ornamental and economic value,a high-quality assembled P.pusilliflora genome is unavailable,hindering our understanding of its genetic background,population diversity,and evolutionary processes.Here,we de novo assembled a chromosome-scale P.pusilliflora genome using Oxford Nanopore,Illumina,and chromosome conformation capture sequencing.The assembled genome size was 309.62 Mb,with 76 scaffolds anchored to eight pseudochromosomes.We predicted 33035 protein-coding genes,functionally annotated 98.27%of them,and identified repetitive sequences covering 49.08%of the genome.We found that P.pusilliflora is closely related to Prunus serrulata and Prunus yedoensis,having diverged from them∼41.8 million years ago.A comparative genomic analysis revealed that P.pusilliflora has 643 expanded and 1128 contracted gene families.Furthermore,we found that P.pusilliflora is more resistant to Colletotrichum viniferum,Phytophthora capsici,and Pseudomonas syringae pv.tomato(Pst)DC3000 infections than cultivated Prunus avium.P.pusilliflora also has considerably more nucleotide-binding site-type resistance gene analogs than P.avium,which explains its stronger disease resistance.The cytochrome P450 and WRKY families of 263 and 61 proteins were divided into 42 and 8 subfamilies respectively in P.pusilliflora.Furthermore,81 MADS-box genes were identified in P.pusilliflora,accompanying expansions of the SVP and AGL15 subfamilies and loss of the TM3 subfamily.Our assembly of a high-quality P.pusilliflora genome will be valuable for further research on cherries and molecular breeding.展开更多
A highly efficient coupling of glycosyl stannanes and sulfonium salts enabled by synergistic Pd/Cu catalysis is disclosed, facilitating the construction of C-aryl/alkenyl glycals under mild conditions in high yields.T...A highly efficient coupling of glycosyl stannanes and sulfonium salts enabled by synergistic Pd/Cu catalysis is disclosed, facilitating the construction of C-aryl/alkenyl glycals under mild conditions in high yields.The protocol tolerates a wide scope of functional groups including ketone, cyano, ester, amide, nitro,halide. The one-pot formal C–H glycosylation starting from arene is demonstrated with a reaction sequence of dibenzothiophenylation/Stille coupling. Besides, a gram-scale reaction is performed successfully,showing the high applicability of this protocol.展开更多
Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge.Diazenes,including 1,1-diazenes and 1,2-diazenes,can generate biradical sp...Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge.Diazenes,including 1,1-diazenes and 1,2-diazenes,can generate biradical species via nitrogen extrusion under thermal or photochemical conditions.The superior reactivity of the generated biradical enables various types of synthetic transformations with excellent chemoselectivity and has been applied to the complex natural products synthesis.In this mini-review,the modes of reaction are summarized and discussed,namely ring contraction via nitrogen deletion,homo or heterodimerization,trimethylenemethane(TMM)-diyl cycloaddition.Applications of these classes of reactions in complex natural product synthesis are illustrated.Last but not least,the current state,future directions,and opportunities for dinitrogen extrusion reaction from diazenes are highlighted and discussed.展开更多
Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established man...Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit.展开更多
Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehic...Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehicles.The re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity instability.Concurrently,these phenomena significantly modulate the evolution of cavitation flow.In this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM framework.Comparative analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction force.These results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.展开更多
Attention mechanism has been a successful method for multimodal affective analysis in recent years. Despite the advances, several significant challenges remain in fusing language and its nonverbal context information....Attention mechanism has been a successful method for multimodal affective analysis in recent years. Despite the advances, several significant challenges remain in fusing language and its nonverbal context information. One is to generate sparse attention coefficients associated with acoustic and visual modalities, which helps locate critical emotional se-mantics. The other is fusing complementary cross‐modal representation to construct optimal salient feature combinations of multiple modalities. A Conditional Transformer Fusion Network is proposed to handle these problems. Firstly, the authors equip the transformer module with CNN layers to enhance the detection of subtle signal patterns in nonverbal sequences. Secondly, sentiment words are utilised as context conditions to guide the computation of cross‐modal attention. As a result, the located nonverbal fea-tures are not only salient but also complementary to sentiment words directly. Experi-mental results show that the authors’ method achieves state‐of‐the‐art performance on several multimodal affective analysis datasets.展开更多
[Objectives]To study the effects of 12%chlorothalonil and 12%procymidone smoke agent on physiology and yield of quinoa in greenhouse.[Methods]The chlorophyll content and photosynthesis rate of quinoa were determined b...[Objectives]To study the effects of 12%chlorothalonil and 12%procymidone smoke agent on physiology and yield of quinoa in greenhouse.[Methods]The chlorophyll content and photosynthesis rate of quinoa were determined by using the conventional application method of smoke agent at the dosage of 3 kg/ha.Finally,the total yield and increased yield of quinoa were calculated.[Results]The chlorophyll content and photosynthesis rate of leaves were all increased by two kinds of smoke agents,and the photosynthesis rate was also increased significantly.[Conclusions]These two smoke agents can promote the growth of quinoa,including the increase of chlorophyll and the enhancement of photosynthesis,and its further mechanism needs to be further discussed.展开更多
Integrated geophysical interpretation is a method of combinating different geophysics prospecting methods based on different physical properties of accumulation. As different geophysical methods own different interpre...Integrated geophysical interpretation is a method of combinating different geophysics prospecting methods based on different physical properties of accumulation. As different geophysical methods own different interpretations and varying detection accuracies, the key issue becomes how to integrate the results of several geophysical methods to corrently carry out a comprehensive explanation. Based on different geophysical results, the authors proposed an integrated geophysical explanation method and successfully applied it in practical engineering problems.展开更多
Integrated Project Delivery(IPD)is a new delivery system that fosters integration of combining design and construction in a collaborative team environment.Building Information Modeling(BIM)is a smart technological too...Integrated Project Delivery(IPD)is a new delivery system that fosters integration of combining design and construction in a collaborative team environment.Building Information Modeling(BIM)is a smart technological tool that make significant advancements in coordinating the planning and construction processes.IPD process with BIM technology allows all building data to maintain in a communicating platform that make all participants share data.In reality,some technical and process obstacles exist,that are hampering full implementation of IPD with BIM in the project.The paper introduced the application of IPD with BIM on the design in a project.The results showed the impact of BIM implementation on IPD mode which can result in improved productivity,better coordination,reduced energy consumption,clash and rework of construction.展开更多
Isolated individual processes of ecosystem carbon (C) cycles have largely shaped our understanding of C cycle processes under environmental change. Yet, in reality, C cycle processes are inter-related and hierarchical...Isolated individual processes of ecosystem carbon (C) cycles have largely shaped our understanding of C cycle processes under environmental change. Yet, in reality, C cycle processes are inter-related and hierarchical. How these processes respond to warming and grazing has rarely been investigated in a single manipulative experiment. Moreover, biodiversity loss is a major driver of ecosystem change under environmental change, but whether these responses are mechanistically linked to biodiversity remains unclear. Here, we performed a 5-year field manipulative warming with seasonal grazing experiment in an alpine meadow on the Qinghai-Tibetan Plateau. Our results showed that both warming and moderate grazing decreased net ecosystem productivity (NEP) by 42.1% and 38.3%, and their interaction decreased it by 56.2% during the summer grazing period. However, they had no significant effects on NEP during the winter grazing period. Overall, annual gross primary productivity (GPP) and ecosystem respiration (Re) were mainly determined by aboveground rather than belowground processes, and Re variation, which was mainly controlled by aboveground respiration explained 50% of the variation in annual NEP under warming and grazing. Moreover, lower species richness induced by warming and grazing caused smaller NEP with smaller net primary productivity and higher aboveground respiration. The responses of aboveground C cycle processes were greater than that of belowground C cycle processes, suggesting asymmetric above- and belowground responses to warming and grazing. Therefore, our findings suggested that there were higher GPP and Re with lower C sequestration (‘two high with one low patterns’) under warming and moderate grazing. Plant diversity modulated the responses of soil C sequestration to warming and grazing. It is essential to understand the underlying mechanisms of the effects of biodiversity on hierarchical C cycle processes under combined warming and grazing in the future.展开更多
文摘Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.92163215,92163212,and 92163119)the Knowledge Innovation Program of Wuhan-Basic Research(Grant No.2022010801010177)the National Innovation and Entrepreneurship Training Program for College Students(Grant No.S202310497212).
文摘The lamellar microstructure is one of the most typical microstructures of TiAl alloys.There are threeγ/γinterfaces with different microstructures in lamellarγ-TiAl alloys.In this work,we investigated the deformation processes of lamellarγ-TiAl alloys with different interfacial spacing(λ)via uniaxial tensile loading using molecular dynamics simulations,including true twin(TT),pseudo-twin(PT),rotational boundary(RB),and the mixed structure(TT∥PT∥RB).The results show that in all lamellarγ-TiAl samples,the Shockley partial dislocation prefers to nucleate in the region between two neighboring interfaces.Then,dislocations move towards,crossing theγ/γinterface.Finally,the dislocation slippage leads to the destruction of the interface,resulting in cracks and structural failure.With the decrease ofλ,the ultimate strength slightly increases in the TT or PT structure ofγ-TiAl,which follows the Hall-Petch relation.But in general,the interfacial spacing has a slight effect on the ultimate strengths of these four structures ofγ-TiAl.
基金the Second Tibetan Plateau Scien-tific Expedition and Research Program(2019QZKK0405)the National Natural Science Foundation of China project Basic Science Center for Tibetan Plateau Earth System(41988101).
文摘Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet it is unknown how these croplands will respond to climate change.Here,using yield statistics from 1985 to 2015,we found that the impact of temperature anomalies on the Tibetan crop yield shifted from nonsignificant(P>0.10)in the 1980s and 1990s to significantly negative(P<0.05)in recent years.Meanwhile,the apparent sensitivity of the crop yield to temperature anomalies almost doubled,from(–0.13±0.20)to(–0.22±0.14)t·ha^(-1)℃^(–1).The emerging negative impacts of higher temperatures suggest an increasing vulnerability of Tibetan croplands to warmer climate.With global warming scenarios of+1.5 or+2.0℃above the pre-industry level,the temperature sensitivities of crop yield may further increase to(–0.33±0.10)and(–0.51±0.18)t·ha^(-1)℃^(–1),respectively,making the crops 2–3 times more vulnerable to warmer temperatures than they are today.
基金supported by the National Natural Science Foundation of China(U21A20472,62072223)the National Key Research and Development Plan of China(2021YFB 3600503)the Natural Science Foundation of Fujian Province(2020J01130193,2020J01131199)。
文摘Dear Editor,This letter proposes a contrastive consensus graph learning model for multi-view clustering.Graphs are usually built to outline the correlation between multi-model objects in clustering task,and multiview graph clustering aims to learn a consensus graph that integrates the spatial property of each view.
基金This work was supported by the National Natural ScienceFoundation of China (Grant No. 51879050, 51609044), the Defense IndustrialTechnology Development Program of China (Grant No. JCKY2017604C002), NaturalScience Foundation of Heilongjiang Province of China (No. E2017021) and ShenzhenSpecial Fund for Future Industries (Grant No. JCYJ20160331163751413).
文摘The low frequency load of an underwater explosion bubble and the generated waves can cause significant rigid motion of a ship that threaten its stability.In order to study the fluid-structure interaction qualitatively,a two-dimensional underwater explosion bubble dynamics model,based on the potential flow theory,is established with a double-vortex model for the doubly connected bubble dynamics simulation,and the bubble shows similar dynamics to that in 3-dimensional domain.A fully nonlinear fluid-structure interaction model is established considering the rigid motion of the floating body using the mode-decomposition method.Convergence test of the model is implemented by simulating the free rolling motion of a floating body in still water.Through the simulation of the interaction of the underwater explosion bubble,the generated waves and the floating body based on the presented model,the influences of the buoyancy parameter and the distance parameter are discussed.It is found that the impact loads on floating body caused by underwater explosion bubble near the free surface can be divided into 3 components:bubble pulsation,jet impact,and slamming load of the generated waves,and the intensity of each component changes nonlinearly with the buoyance parameter.The bubble pulsation load decays with the increase in the horizontal distance.However,the impact load from the generated waves is not monotonous to distance.It increases with the distance within a particular distance threshold,but decays thereafter.
基金supported by the Natural Science Foundation Committee of China(41230750 and 41101081)Key Program of the Chinese Academy of Sciences(KFZD-SW-312)the"National Key Research and Development Program of China"(2016YFC0501802)
文摘Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau.However,it is unclear whether fencing reduces CO_(2),CH_4,and N_2O emission.Here,we selected four vegetation types of alpine meadow(graminoid,shrub,forb,and sparse vegetation)to determine fencing effects on ecosystem respiration(Re),CH_4,and N_2O fluxes during the growing season.Despite increased average monthly ecosystem respiration(Re)for fenced graminoid vegetation at the end of the growing season,there was no significant difference between grazing and fencing across all vegetation types.Fencing significantly reduced average CH_4 uptake by about 50%in 2008 only for forb vegetation and increased average N_2O release for graminoid vegetation by 38%and 48%in 2008 and 2009,respectively.Temperature,moisture,total organic carbon,C/N,nitrate,ammonia,and/or bulk density of soil,as well as above-and belowground biomass,explained 19%~71%and 6%~33%of variation in daily and average Re and CH_4 fluxes across all vegetation types,while soil-bulk density explained 27%of variation in average N_2O fluxes.Stepwise regression showed that soil temperature and soil moisture controlled average Re,while soil moisture and bulk density controlled average CH_4 fluxes.These results indicate that abiotic factors control Re,CH_4,and N_2O fluxes;and grazing exclusion has little effect on reducing their emission—implying that climatic change rather than grazing may have a more important influence on the budgets of Re and CH_4 for the Tibetan alpine meadow during the growing season.
基金This study was funded by the Shanghai Agriculture Applied Technology Development Program,China(grant no.2022-02-08-00-12-F01111)the China Agriculture Research System(grant no.CARS-30-2-08)+2 种基金the National Natural Science Foundation of China(grant no.32102347)the Shanghai Sailing Program(grant no.21YF1422100)the Startup Fund for Young Faculty at SJTU(grant no.21X010500643).
文摘Prunus pusilliflora is a wild cherry germplasm resource distributed mainly in Southwest China.Despite its ornamental and economic value,a high-quality assembled P.pusilliflora genome is unavailable,hindering our understanding of its genetic background,population diversity,and evolutionary processes.Here,we de novo assembled a chromosome-scale P.pusilliflora genome using Oxford Nanopore,Illumina,and chromosome conformation capture sequencing.The assembled genome size was 309.62 Mb,with 76 scaffolds anchored to eight pseudochromosomes.We predicted 33035 protein-coding genes,functionally annotated 98.27%of them,and identified repetitive sequences covering 49.08%of the genome.We found that P.pusilliflora is closely related to Prunus serrulata and Prunus yedoensis,having diverged from them∼41.8 million years ago.A comparative genomic analysis revealed that P.pusilliflora has 643 expanded and 1128 contracted gene families.Furthermore,we found that P.pusilliflora is more resistant to Colletotrichum viniferum,Phytophthora capsici,and Pseudomonas syringae pv.tomato(Pst)DC3000 infections than cultivated Prunus avium.P.pusilliflora also has considerably more nucleotide-binding site-type resistance gene analogs than P.avium,which explains its stronger disease resistance.The cytochrome P450 and WRKY families of 263 and 61 proteins were divided into 42 and 8 subfamilies respectively in P.pusilliflora.Furthermore,81 MADS-box genes were identified in P.pusilliflora,accompanying expansions of the SVP and AGL15 subfamilies and loss of the TM3 subfamily.Our assembly of a high-quality P.pusilliflora genome will be valuable for further research on cherries and molecular breeding.
基金Fuzhou University (No. 511041)the Fujian Provincial Department of Education (No. 602512) for financial support。
文摘A highly efficient coupling of glycosyl stannanes and sulfonium salts enabled by synergistic Pd/Cu catalysis is disclosed, facilitating the construction of C-aryl/alkenyl glycals under mild conditions in high yields.The protocol tolerates a wide scope of functional groups including ketone, cyano, ester, amide, nitro,halide. The one-pot formal C–H glycosylation starting from arene is demonstrated with a reaction sequence of dibenzothiophenylation/Stille coupling. Besides, a gram-scale reaction is performed successfully,showing the high applicability of this protocol.
基金Fuzhou University for the funding support(No.GXRC21051)the Award Program for Minjiang Scholar Professorship。
文摘Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge.Diazenes,including 1,1-diazenes and 1,2-diazenes,can generate biradical species via nitrogen extrusion under thermal or photochemical conditions.The superior reactivity of the generated biradical enables various types of synthetic transformations with excellent chemoselectivity and has been applied to the complex natural products synthesis.In this mini-review,the modes of reaction are summarized and discussed,namely ring contraction via nitrogen deletion,homo or heterodimerization,trimethylenemethane(TMM)-diyl cycloaddition.Applications of these classes of reactions in complex natural product synthesis are illustrated.Last but not least,the current state,future directions,and opportunities for dinitrogen extrusion reaction from diazenes are highlighted and discussed.
基金supported by the projects of China Agriculture Research System of MOF and MARA (Grant No.CARS-29-ZP-7)Outstanding Youth Science and Technology Fund of Henan Academy of Agricultural Sciences (Grant No.2022YQ08)。
文摘Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit.
基金supported by the National Natural Science Foundation of China(Nos.12202011,12332014)China Postdoctoral Science Foundation(No.2022M710190).
文摘Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater vehicles.The re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity instability.Concurrently,these phenomena significantly modulate the evolution of cavitation flow.In this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM framework.Comparative analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction force.These results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.
基金National Key Research and Development Plan of China, Grant/Award Number: 2021YFB3600503National Natural Science Foundation of China, Grant/Award Numbers: 62276065, U21A20472。
文摘Attention mechanism has been a successful method for multimodal affective analysis in recent years. Despite the advances, several significant challenges remain in fusing language and its nonverbal context information. One is to generate sparse attention coefficients associated with acoustic and visual modalities, which helps locate critical emotional se-mantics. The other is fusing complementary cross‐modal representation to construct optimal salient feature combinations of multiple modalities. A Conditional Transformer Fusion Network is proposed to handle these problems. Firstly, the authors equip the transformer module with CNN layers to enhance the detection of subtle signal patterns in nonverbal sequences. Secondly, sentiment words are utilised as context conditions to guide the computation of cross‐modal attention. As a result, the located nonverbal fea-tures are not only salient but also complementary to sentiment words directly. Experi-mental results show that the authors’ method achieves state‐of‐the‐art performance on several multimodal affective analysis datasets.
基金Supported by Introduction and Demonstration Project of Forage Quinoa Germplasm Resources(2019YX019A)Project of Hebei Academy of Agricultural and Forestry Sciences(Basic Scientific Research Fund 2018030302Innovation Project F19R494004-01-5).
文摘[Objectives]To study the effects of 12%chlorothalonil and 12%procymidone smoke agent on physiology and yield of quinoa in greenhouse.[Methods]The chlorophyll content and photosynthesis rate of quinoa were determined by using the conventional application method of smoke agent at the dosage of 3 kg/ha.Finally,the total yield and increased yield of quinoa were calculated.[Results]The chlorophyll content and photosynthesis rate of leaves were all increased by two kinds of smoke agents,and the photosynthesis rate was also increased significantly.[Conclusions]These two smoke agents can promote the growth of quinoa,including the increase of chlorophyll and the enhancement of photosynthesis,and its further mechanism needs to be further discussed.
基金Project of Research on Integrated Geophysical Interpretation on Accumulation (No. CHC-KJ-2004-11)
文摘Integrated geophysical interpretation is a method of combinating different geophysics prospecting methods based on different physical properties of accumulation. As different geophysical methods own different interpretations and varying detection accuracies, the key issue becomes how to integrate the results of several geophysical methods to corrently carry out a comprehensive explanation. Based on different geophysical results, the authors proposed an integrated geophysical explanation method and successfully applied it in practical engineering problems.
基金the support by the Housing and Urban-Rural Development Department of Shandong Province“specific topic”(No.2020-K1-7).
文摘Integrated Project Delivery(IPD)is a new delivery system that fosters integration of combining design and construction in a collaborative team environment.Building Information Modeling(BIM)is a smart technological tool that make significant advancements in coordinating the planning and construction processes.IPD process with BIM technology allows all building data to maintain in a communicating platform that make all participants share data.In reality,some technical and process obstacles exist,that are hampering full implementation of IPD with BIM in the project.The paper introduced the application of IPD with BIM on the design in a project.The results showed the impact of BIM implementation on IPD mode which can result in improved productivity,better coordination,reduced energy consumption,clash and rework of construction.
基金supported by projects from the Chinese Academy of Sciences (CAS) Project for Young Scientists in Basic Research (YSBR-037)the Postdoctoral Fellowship Program of CPSF (GZB20240779)+1 种基金projects of the Naqu Science and Technology Bureau (NQKJ-2023-03)the Ali Science and Technology Bureau (QYTZZX-AL2022-05) of Xizang Autonomous Region。
文摘Isolated individual processes of ecosystem carbon (C) cycles have largely shaped our understanding of C cycle processes under environmental change. Yet, in reality, C cycle processes are inter-related and hierarchical. How these processes respond to warming and grazing has rarely been investigated in a single manipulative experiment. Moreover, biodiversity loss is a major driver of ecosystem change under environmental change, but whether these responses are mechanistically linked to biodiversity remains unclear. Here, we performed a 5-year field manipulative warming with seasonal grazing experiment in an alpine meadow on the Qinghai-Tibetan Plateau. Our results showed that both warming and moderate grazing decreased net ecosystem productivity (NEP) by 42.1% and 38.3%, and their interaction decreased it by 56.2% during the summer grazing period. However, they had no significant effects on NEP during the winter grazing period. Overall, annual gross primary productivity (GPP) and ecosystem respiration (Re) were mainly determined by aboveground rather than belowground processes, and Re variation, which was mainly controlled by aboveground respiration explained 50% of the variation in annual NEP under warming and grazing. Moreover, lower species richness induced by warming and grazing caused smaller NEP with smaller net primary productivity and higher aboveground respiration. The responses of aboveground C cycle processes were greater than that of belowground C cycle processes, suggesting asymmetric above- and belowground responses to warming and grazing. Therefore, our findings suggested that there were higher GPP and Re with lower C sequestration (‘two high with one low patterns’) under warming and moderate grazing. Plant diversity modulated the responses of soil C sequestration to warming and grazing. It is essential to understand the underlying mechanisms of the effects of biodiversity on hierarchical C cycle processes under combined warming and grazing in the future.
