Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entanglement between the two-level atom and the two-mode field by using the quantum reduced entropy, and that bet...Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entanglement between the two-level atom and the two-mode field by using the quantum reduced entropy, and that between the two-mode field by using the quantum relative entropy of entanglement. It shows that the two kinds of entanglement are dependent on the relative coupling strength of atom-field and the atomic distribution, and exhibit the periodical evolution. The maximal atom-field entanglement state can be prepared via the appropriate selection of system parameters and interaction time.展开更多
This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈...This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈R.(0.1)Here a≠1,b≠1,d,and r are positive constants.By studying the eigenvalue problem of(0.1)linearized at(ϕc(ξ),0),we construct a pair of super-and sub-solutions for(0.1),and then establish the existence of entire solutions originating from(ϕc(ξ),0)as t→−∞,whereϕc denotes the traveling wave solution of the nonlocal Fisher-KPP equation ut=k*u−u+u(1−u).Moreover,we give a detailed description on the long-time behavior of such entire solutions as t→∞.Compared to the known works on the Lotka-Volterra competition system with classical diffusions,this paper overcomes many difficulties due to the appearance of nonlocal dispersal operators.展开更多
In this paper, the Lotka-Volterra competition system with discrete and distributed time delays is considered. By analyzing the characteristic equation of the linearized system, the local asymptotic stability of the po...In this paper, the Lotka-Volterra competition system with discrete and distributed time delays is considered. By analyzing the characteristic equation of the linearized system, the local asymptotic stability of the positive equilibrium is investigated. Moreover, we discover the delays don＇t effect the stability of the equilibrium in the delay system. Finally, we can conclude that the positive equilibrium is global asymptotically stable in the delay system.展开更多
This study analyzes the current situation and problems of the school football competition system in Chongqing through literature search,interviews,and questionnaires.With this,a development model suitable for the esta...This study analyzes the current situation and problems of the school football competition system in Chongqing through literature search,interviews,and questionnaires.With this,a development model suitable for the establishment of a school football system for young people is proposed.Besides,this study aims to promote the construction and improvement and boost the competitiveness of school football competition system.展开更多
The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics...The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics with one extinct species, by applying the technique of average functions and the new principle of competitive exclusion.展开更多
By using the continuation theorem of coincidence theory,the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional response x_(1)(t)=x_(1)(t)a_(1)(t...By using the continuation theorem of coincidence theory,the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional response x_(1)(t)=x_(1)(t)a_(1)(t)-b_(1)(t)x_(1)(t)-c_(1)(t)y(t)1+m(t)x_(1)(t)+D_(1)(t)[x_(2)(t)-x_(1)(t)],x_(2)(t)=x_(2)(t)a_(2)(t)-b_(2)(t)x_(2)(t)-c_(2)(t)∫^(0)_(-τ)k(s)x_(2)(t+s)d s+D_(2)(t)[x_(1)(t)-x_(2)(t)],y′(t)=y(t)a_(3)(t)-b_(3)(t)y(t)-c_(3)(t)x_(1)(t)1+m(t)x_(1)(t)is established,where a i(t),b_(i)(t),c_(i)(t)(i=1,2,3),m(t)and D_(i)(t)(i=1,2)are all positive periodic continuous functions with period w>0,τis a nonnegative constant and k(s)is a continuous nonnegative function on[-τ,0].展开更多
The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial st...The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial state of thesystem and the relative coupling strength between the atom and the field on the atomic information entropy squeezingare discussed.Our results show that the squeezed direction and the frequency of the information entropy squeezing canbe controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field,respectively.We find that,under the same condition,no atomic variance squeezing is predicted from the HUR while optimal entropysqueezing is obtained from the EUR,so the quantum information entropy is a remarkable precision measure for theatomic squeezing in the considered system.展开更多
Understanding the cooperation-competition dynamics is a long-standing challenge in studying complex systems.Inspired by the idea of Shannon entropy, we define competition information entropy and propose an entropy evo...Understanding the cooperation-competition dynamics is a long-standing challenge in studying complex systems.Inspired by the idea of Shannon entropy, we define competition information entropy and propose an entropy evolution model. The analytic results of the model of the relation between competition gain distribution parameters and entropy, as well as the relation between entropy and time are compared with empirical results obtained in 14 real world systems. They are found to be in good agreement with each other.展开更多
The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, cha...The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.展开更多
During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their el...During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.展开更多
Background The mulch-free subsurface drip irrigation system demonstrated water-saving potential as an alternative to traditional mulch-based drip irrigation while also eliminating residual film pollution at source.How...Background The mulch-free subsurface drip irrigation system demonstrated water-saving potential as an alternative to traditional mulch-based drip irrigation while also eliminating residual film pollution at source.However,delayed sowing is unavoidable in mulch-free cultivation in ecological regions with a short frost-free period.Intercropping with cumin,which has a shorter growth period,served as an effective strategy to improve land use efficiency during the early growth stages of cotton.Therefore,a two-year field experiment was conducted to study the effects of intercropping cumin at the seeding rate of 2.5(ID1),3.85(ID2),and 5.2(ID3)kg・hm−2 on cotton growth,interspecies competition,fiber quality,and water use efficiency(WUE),as well as system economic benefits under subsurface drip irrigation.Monocropping cotton was used as the control(CK)treatment.Results At the initial flowering(IF)stage(the end of the co-growth period of cotton and cumin),cotton plant height in ID2 and ID3 treatments decreased by 5.93%–16.53%and 10.87%–31.11%,respectively,cotton stem diameter by 11.41%–14.25%and 3.37%–26.49%,respectively,and vegetative biomass by 14.46%–30.65%and 22.59%–49.91%,respectively,compared with CK treatment.With the increase in cumin density,the crop growth rate(CGR)and compensation effect in cotton tended to significantly decrease at the IF stage regardless of organs considered.For the non-co-growth period(after harvesting cumin),cotton reproductive organ biomass in ID2 and ID3 treatments increased by 4.09%‒14.61%at the boll opening stage,crop growth rate in reproductive organs by 20.74%and 74.26%from peak boll to boll opening stages compared with CK treatment,due to an enhancement of 19.09%and 49.30%in the compensation effect.Compared with ID1,the aggressivity treated by ID2 and ID3 decreased by 12.82%–46.34%and 17.95%–31.71%,respectively.However,owing to a greater number of green bolls in the upper canopy at the harvest stages in the ID3 treatment,the system production value(closely related to yield)treated by ID2 was 11.69%–16.89%,6.56%–20.02%,and 16.48%–59.83%greater than that of the ID1,ID3,and CK treatments,respectively.This also led to the highest WUE and net profit under the ID2 treatment.Conclusion Intercropping cumin with medium density improved the cotton biomass accumulation characteristics and increased resources such as land and water utilization efficiency and economic benefits through a stronger compensation effect after harvesting cumin under subsurface drip irrigation without mulch.This study not only provides alternatives to residual film pollution in arid cotton fields but also establishes a sustainable agro-ecological-economic planting paradigm by reducing plastic use and enhancing water and fertilizer use efficiency,holding significant implications for advancing resource-efficient agricultural systems.展开更多
Brain size varies dramatically across populations and species in anuran species.The differences in structure,function,or size of brains are linked to processing specific cognitive tasks by different behaviors.In parti...Brain size varies dramatically across populations and species in anuran species.The differences in structure,function,or size of brains are linked to processing specific cognitive tasks by different behaviors.In particular,the causes of how male-male competition promotes the increased cognitive abilities to increase brains are as yet unexplored in anurans.To evaluate the effect of male-male competition on variation in brain size in B.andrewsi,we compared the differences in relative brain size between mated males and unpaired males under natural and experimental conditions.We found that mated males had relatively larger brains than unpaired males in a natural population when controlling the effect of body size.Likewise,we also found that there were larger brains in mated males than in unpaired males in both experiment 1 where two males competed for a female and experiment 2 where three males competed for a female,suggesting that males with mating success during male-male competition possess increased brain size and cognitive abilities.When we compared difference in relative brain size in mated males between experiment2 and experiment 1 we found that males experiencing more intense competition did not display larger brains than males experiencing relatively weak competition,suggesting that low intensity competition is already enough to trigger the increase in relative brain size in B.andrewsi.展开更多
Droughts have caused tree growth decline and high tree mortality across temperate forests,however,how to manage planted forests to alleviate drought stress is still challenging.We used tree-ring and forest inventory d...Droughts have caused tree growth decline and high tree mortality across temperate forests,however,how to manage planted forests to alleviate drought stress is still challenging.We used tree-ring and forest inventory data from different density stands to investigate how competition,tree diameter at breast height(DBH),tree age,and their interactions influence drought sensitivity and resistance for three widely-distributed and planted conifer species(Larix principis-rupprechtii,Picea meyeri,and Pinus sylvestris var.mongolica).Our results showed that the drought sensitivity of the three species was influenced by competition,tree size,and their interactions.Large L.principis-rupprechtii trees were particularly sensitive to drought during the growing season in medium to high-density stands,while the growth of large P.sylvestris var.mongolica was most affected by precipitation at low to medium density stands.Drought resistance of L.principis-rupprechtii trees decreased as tree size increased.Large L.principis-rupprechtii trees had lower drought resistance than small trees in all stands.Drought resistance of large P.meyeri trees exhibited high resistance to drought only in high-density stands.However,drought resistance of P.sylvestris var.mongolica trees was affected by tree size,competition,and their interactions.These results indicated that targeted silvicultural interventions,such as thinning,can be implemented to enhance drought resistance specifically for large L.principis-rupprechtii trees and small P.sylvestris var.mongolica trees in medium and high competition stands,and small P.meyeri trees in high competition stands.Our results highlight that properly conducted thinning can in some cases enhance growth resistance to droughts,depending on stand density,tree size,and tree species.展开更多
Neighborhood competition is a critical driver of individual tree growth,and aboveground biomass(AGB)accumulation,which together play key roles in forest dynamics and carbon storage.Therefore,accurate biomass estimatio...Neighborhood competition is a critical driver of individual tree growth,and aboveground biomass(AGB)accumulation,which together play key roles in forest dynamics and carbon storage.Therefore,accurate biomass estimation is essential for understanding ecosystem functioning and informing forest management strategies to mitigate climate change.However,integrating neighborhood competition into biomass estimation models,particularly for young mixed forest stands,remains unexplored.In this study,we examined how incorporating neighborhood competition improves biomass prediction accuracy and how the influence of neighborhood competition differs between Scots pine(Pinus sylvestris L.)and Pyrenean oak(Quercus pyrenaica Willd.),as well as the relative contributions of intra-and interspecific competition to AGB.Our findings revealed that including neighborhood competition alongside tree size variables(DBH and total tree height)significantly improved the predictive accuracy of AGB models for Scots pine.This addition reduced the root mean square error(RMSE)by 14% and improved the model efficiency factor(MEF)by 15%.Furthermore,intraspecific competition in Scots pine slightly reduced AGB,whereas interspecific competition had a significant negative effect on AGB.In contrast,DBH alone was the best predictor of AGB for Pyrenean oak,as neighborhood competition did not improve model performance.Also,intra-and interspecific competition in Pyrenean oak had positive but nonsignificant effects on AGB.These findings highlight the important role of competition in biomass models and suggest species-specific approaches in competition dynamics to inform sustainable forest management and climate change adaptation strategies.展开更多
Autosamplers are indispensable key equipment in modern laboratories,playing a pivotal role in fields such as biomedicine,environmental monitoring,food safety,and materials science.However,domestic autosampler enterpri...Autosamplers are indispensable key equipment in modern laboratories,playing a pivotal role in fields such as biomedicine,environmental monitoring,food safety,and materials science.However,domestic autosampler enterprises are facing formidable challenges,confronted by the technological barriers and brand dominance of international giants,as well as increasingly fierce homogeneous competition in the domestic market.This article aims to thoroughly analyze the current market landscape and,based on seven key dimensions—strategic positioning,product technology,sales channels,brand building,service and support,supply chain optimization,and talent development—propose a series of effective market-winning strategies.This will provide theoretical guidance and practical reference for domestic autosampler enterprises to achieve breakthroughs and sustainable development amidst fierce market competition.展开更多
Droughts pose significant threats to forest ecosystems globally.Effective forest management strategies,adapted to local conditions,are needed to mitigate negative drought impacts.One proposed strategy is competition r...Droughts pose significant threats to forest ecosystems globally.Effective forest management strategies,adapted to local conditions,are needed to mitigate negative drought impacts.One proposed strategy is competition reduction to increase water availability and,as a result,alleviate drought stress.This study investigates the effect of competition intensity on drought stress and tree growth in European beech(Fagus sylvatica)and pedunculate oak(Quercus robur).We deployed 72 point dendrometers,placed along a competition intensity gradient,in National Park Brabantse Wouden(Belgium),to measure daily minimum tree water deficit(TWD_(min))as a drought stress proxy and daily radial growth at tree level.Our results revealed species-dependent effects of competition intensity(CI).For European beech,competition reductions positively influenced growth and alleviated(1<CI<2)or aggravated(CI<0.5)drought stress.For pedunculate oak,competition intensity did not affect drought stress or growth along the investigated gradient.Environmental variables consistently affected TWDmin and growth of both species.Precipitation reduced TWDmin and increased growth,while vapor pressure deficit led to opposite trends.Thus,environmental conditions and competition can play a critical role in forest dynamics,especially in light of climate change.However,reducing competition through increased management efforts does not seem to be a one-size-fits-all solution to alleviating drought stress.Additionally,there seems to be a trade-off between reducing drought stress and improving tree growth in European beech:tree growth continuously benefited from competition reductions,while under low competition(CI<0.5)drought stress increased.Revisiting or reviving long-term thinning intensity trials encompassing various regions,species,and soil types will be needed to gain comprehensive insights into mitigating drought stress through management interventions under different local stand conditions.展开更多
The deep sea holds vital resources and spatial potential for future human survival and development,reflecting the common interests and concerns of all mankind.Amidst unprecedented global transformations in a hundred y...The deep sea holds vital resources and spatial potential for future human survival and development,reflecting the common interests and concerns of all mankind.Amidst unprecedented global transformations in a hundred years,the deep sea has emerged as a critical area of international competition and serves as a new frontier for resource extraction,a strategic space for military competition,and a contested space for great power rivalry and rule-making.展开更多
As a complicated optimization problem,parallel batch processing machines scheduling problem(PBPMSP)exists in many real-life manufacturing industries such as textiles and semiconductors.Machine eligibility means that a...As a complicated optimization problem,parallel batch processing machines scheduling problem(PBPMSP)exists in many real-life manufacturing industries such as textiles and semiconductors.Machine eligibility means that at least one machine is not eligible for at least one job.PBPMSP and scheduling problems with machine eligibility are frequently considered;however,PBPMSP with machine eligibility is seldom explored.This study investigates PBPMSP with machine eligibility in fabric dyeing and presents a novel shuffled frog-leaping algorithm with competition(CSFLA)to minimize makespan.In CSFLA,the initial population is produced in a heuristic and random way,and the competitive search of memeplexes comprises two phases.Competition between any two memeplexes is done in the first phase,then iteration times are adjusted based on competition,and search strategies are adjusted adaptively based on the evolution quality of memeplexes in the second phase.An adaptive population shuffling is given.Computational experiments are conducted on 100 instances.The computational results showed that the new strategies of CSFLA are effective and that CSFLA has promising advantages in solving the considered PBPMSP.展开更多
基金supported by the National Natural Science Foundation of China (Grant No 10374025)
文摘Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entanglement between the two-level atom and the two-mode field by using the quantum reduced entropy, and that between the two-mode field by using the quantum relative entropy of entanglement. It shows that the two kinds of entanglement are dependent on the relative coupling strength of atom-field and the atomic distribution, and exhibit the periodical evolution. The maximal atom-field entanglement state can be prepared via the appropriate selection of system parameters and interaction time.
基金supported by the NSF of China (12271226)the NSF of Gansu Province of China (21JR7RA537)+4 种基金the Fundamental Research Funds for the Central Universities (lzujbky-2022-sp07)supported by the Basic and Applied Basic Research Foundation of Guangdong Province (2023A1515011757)the National Natural Science Foundation of China (12271494)the Fundamental Research Funds for the Central Universities,China University of Geosciences (Wuhan) (G1323523061)supported by the NSF of China (12201434).
文摘This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈R.(0.1)Here a≠1,b≠1,d,and r are positive constants.By studying the eigenvalue problem of(0.1)linearized at(ϕc(ξ),0),we construct a pair of super-and sub-solutions for(0.1),and then establish the existence of entire solutions originating from(ϕc(ξ),0)as t→−∞,whereϕc denotes the traveling wave solution of the nonlocal Fisher-KPP equation ut=k*u−u+u(1−u).Moreover,we give a detailed description on the long-time behavior of such entire solutions as t→∞.Compared to the known works on the Lotka-Volterra competition system with classical diffusions,this paper overcomes many difficulties due to the appearance of nonlocal dispersal operators.
基金the Education Foundation of Henan Province(07110005)
文摘In this paper, the Lotka-Volterra competition system with discrete and distributed time delays is considered. By analyzing the characteristic equation of the linearized system, the local asymptotic stability of the positive equilibrium is investigated. Moreover, we discover the delays don＇t effect the stability of the equilibrium in the delay system. Finally, we can conclude that the positive equilibrium is global asymptotically stable in the delay system.
文摘This study analyzes the current situation and problems of the school football competition system in Chongqing through literature search,interviews,and questionnaires.With this,a development model suitable for the establishment of a school football system for young people is proposed.Besides,this study aims to promote the construction and improvement and boost the competitiveness of school football competition system.
文摘The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics with one extinct species, by applying the technique of average functions and the new principle of competitive exclusion.
基金Supported by the National Natural Science Foundation of China(19531070)the Major and Youth Project Foundation of Hubei Province Education Department(2001Z06003)(2002B00002).
文摘By using the continuation theorem of coincidence theory,the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional response x_(1)(t)=x_(1)(t)a_(1)(t)-b_(1)(t)x_(1)(t)-c_(1)(t)y(t)1+m(t)x_(1)(t)+D_(1)(t)[x_(2)(t)-x_(1)(t)],x_(2)(t)=x_(2)(t)a_(2)(t)-b_(2)(t)x_(2)(t)-c_(2)(t)∫^(0)_(-τ)k(s)x_(2)(t+s)d s+D_(2)(t)[x_(1)(t)-x_(2)(t)],y′(t)=y(t)a_(3)(t)-b_(3)(t)y(t)-c_(3)(t)x_(1)(t)1+m(t)x_(1)(t)is established,where a i(t),b_(i)(t),c_(i)(t)(i=1,2,3),m(t)and D_(i)(t)(i=1,2)are all positive periodic continuous functions with period w>0,τis a nonnegative constant and k(s)is a continuous nonnegative function on[-τ,0].
基金National Natural Science Foundation of China under Grant No:10374025the Education Department of Hunan Province of China under Grant No.06A038
文摘The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial state of thesystem and the relative coupling strength between the atom and the field on the atomic information entropy squeezingare discussed.Our results show that the squeezed direction and the frequency of the information entropy squeezing canbe controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field,respectively.We find that,under the same condition,no atomic variance squeezing is predicted from the HUR while optimal entropysqueezing is obtained from the EUR,so the quantum information entropy is a remarkable precision measure for theatomic squeezing in the considered system.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10635040 and 70671089)
文摘Understanding the cooperation-competition dynamics is a long-standing challenge in studying complex systems.Inspired by the idea of Shannon entropy, we define competition information entropy and propose an entropy evolution model. The analytic results of the model of the relation between competition gain distribution parameters and entropy, as well as the relation between entropy and time are compared with empirical results obtained in 14 real world systems. They are found to be in good agreement with each other.
文摘The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.
基金supported by Catalan Government,Nos.2014SGR344(to JT),2017SGR704(to JT),2021SGR01214(to MAL)MCIN/AEI/10.13039/501100011033/by“ERDF A way of making Europe,”Nos.SAF2015-67143(to JT),PID2019-106332GB-I00(to JT and MAL)and PID2022-141252NB-I00(to MAL).
文摘During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.
基金supported by the National Natural Science Foundation of China(31250512).
文摘Background The mulch-free subsurface drip irrigation system demonstrated water-saving potential as an alternative to traditional mulch-based drip irrigation while also eliminating residual film pollution at source.However,delayed sowing is unavoidable in mulch-free cultivation in ecological regions with a short frost-free period.Intercropping with cumin,which has a shorter growth period,served as an effective strategy to improve land use efficiency during the early growth stages of cotton.Therefore,a two-year field experiment was conducted to study the effects of intercropping cumin at the seeding rate of 2.5(ID1),3.85(ID2),and 5.2(ID3)kg・hm−2 on cotton growth,interspecies competition,fiber quality,and water use efficiency(WUE),as well as system economic benefits under subsurface drip irrigation.Monocropping cotton was used as the control(CK)treatment.Results At the initial flowering(IF)stage(the end of the co-growth period of cotton and cumin),cotton plant height in ID2 and ID3 treatments decreased by 5.93%–16.53%and 10.87%–31.11%,respectively,cotton stem diameter by 11.41%–14.25%and 3.37%–26.49%,respectively,and vegetative biomass by 14.46%–30.65%and 22.59%–49.91%,respectively,compared with CK treatment.With the increase in cumin density,the crop growth rate(CGR)and compensation effect in cotton tended to significantly decrease at the IF stage regardless of organs considered.For the non-co-growth period(after harvesting cumin),cotton reproductive organ biomass in ID2 and ID3 treatments increased by 4.09%‒14.61%at the boll opening stage,crop growth rate in reproductive organs by 20.74%and 74.26%from peak boll to boll opening stages compared with CK treatment,due to an enhancement of 19.09%and 49.30%in the compensation effect.Compared with ID1,the aggressivity treated by ID2 and ID3 decreased by 12.82%–46.34%and 17.95%–31.71%,respectively.However,owing to a greater number of green bolls in the upper canopy at the harvest stages in the ID3 treatment,the system production value(closely related to yield)treated by ID2 was 11.69%–16.89%,6.56%–20.02%,and 16.48%–59.83%greater than that of the ID1,ID3,and CK treatments,respectively.This also led to the highest WUE and net profit under the ID2 treatment.Conclusion Intercropping cumin with medium density improved the cotton biomass accumulation characteristics and increased resources such as land and water utilization efficiency and economic benefits through a stronger compensation effect after harvesting cumin under subsurface drip irrigation without mulch.This study not only provides alternatives to residual film pollution in arid cotton fields but also establishes a sustainable agro-ecological-economic planting paradigm by reducing plastic use and enhancing water and fertilizer use efficiency,holding significant implications for advancing resource-efficient agricultural systems.
基金funded by the National Natural Science Foundation of China (32370456)the Key Project of Natural Sciences Foundation of Sichuan Province (22NSFSC0011)。
文摘Brain size varies dramatically across populations and species in anuran species.The differences in structure,function,or size of brains are linked to processing specific cognitive tasks by different behaviors.In particular,the causes of how male-male competition promotes the increased cognitive abilities to increase brains are as yet unexplored in anurans.To evaluate the effect of male-male competition on variation in brain size in B.andrewsi,we compared the differences in relative brain size between mated males and unpaired males under natural and experimental conditions.We found that mated males had relatively larger brains than unpaired males in a natural population when controlling the effect of body size.Likewise,we also found that there were larger brains in mated males than in unpaired males in both experiment 1 where two males competed for a female and experiment 2 where three males competed for a female,suggesting that males with mating success during male-male competition possess increased brain size and cognitive abilities.When we compared difference in relative brain size in mated males between experiment2 and experiment 1 we found that males experiencing more intense competition did not display larger brains than males experiencing relatively weak competition,suggesting that low intensity competition is already enough to trigger the increase in relative brain size in B.andrewsi.
基金funded by State Key Research and Development Program of China(No.2023YFD2200401)S&T Program of Hebei(Nos.226Z6801G,22326807D)Talent Introduction Program in Hebei Agricultural University(No.YJ201918).
文摘Droughts have caused tree growth decline and high tree mortality across temperate forests,however,how to manage planted forests to alleviate drought stress is still challenging.We used tree-ring and forest inventory data from different density stands to investigate how competition,tree diameter at breast height(DBH),tree age,and their interactions influence drought sensitivity and resistance for three widely-distributed and planted conifer species(Larix principis-rupprechtii,Picea meyeri,and Pinus sylvestris var.mongolica).Our results showed that the drought sensitivity of the three species was influenced by competition,tree size,and their interactions.Large L.principis-rupprechtii trees were particularly sensitive to drought during the growing season in medium to high-density stands,while the growth of large P.sylvestris var.mongolica was most affected by precipitation at low to medium density stands.Drought resistance of L.principis-rupprechtii trees decreased as tree size increased.Large L.principis-rupprechtii trees had lower drought resistance than small trees in all stands.Drought resistance of large P.meyeri trees exhibited high resistance to drought only in high-density stands.However,drought resistance of P.sylvestris var.mongolica trees was affected by tree size,competition,and their interactions.These results indicated that targeted silvicultural interventions,such as thinning,can be implemented to enhance drought resistance specifically for large L.principis-rupprechtii trees and small P.sylvestris var.mongolica trees in medium and high competition stands,and small P.meyeri trees in high competition stands.Our results highlight that properly conducted thinning can in some cases enhance growth resistance to droughts,depending on stand density,tree size,and tree species.
基金the 2019 call for the predoctoral contract at the University of Valladolid cofinanced by Banco de Santander and projects‘CLU-2019-01-Unidad de Excelencia Instituto iuFOR’,‘PID2021-126275OB-C21’and‘PID2021-126275OB-C22’-Integrated Forest Management along complexity gradients(IMFLEX)‘MCIN/AEI/10.13039/501100011033/FEDER,UE’,which received financial support from the Regional Government of Castilla and León,Spainthe European Regional Development Fund(ERDF).
文摘Neighborhood competition is a critical driver of individual tree growth,and aboveground biomass(AGB)accumulation,which together play key roles in forest dynamics and carbon storage.Therefore,accurate biomass estimation is essential for understanding ecosystem functioning and informing forest management strategies to mitigate climate change.However,integrating neighborhood competition into biomass estimation models,particularly for young mixed forest stands,remains unexplored.In this study,we examined how incorporating neighborhood competition improves biomass prediction accuracy and how the influence of neighborhood competition differs between Scots pine(Pinus sylvestris L.)and Pyrenean oak(Quercus pyrenaica Willd.),as well as the relative contributions of intra-and interspecific competition to AGB.Our findings revealed that including neighborhood competition alongside tree size variables(DBH and total tree height)significantly improved the predictive accuracy of AGB models for Scots pine.This addition reduced the root mean square error(RMSE)by 14% and improved the model efficiency factor(MEF)by 15%.Furthermore,intraspecific competition in Scots pine slightly reduced AGB,whereas interspecific competition had a significant negative effect on AGB.In contrast,DBH alone was the best predictor of AGB for Pyrenean oak,as neighborhood competition did not improve model performance.Also,intra-and interspecific competition in Pyrenean oak had positive but nonsignificant effects on AGB.These findings highlight the important role of competition in biomass models and suggest species-specific approaches in competition dynamics to inform sustainable forest management and climate change adaptation strategies.
文摘Autosamplers are indispensable key equipment in modern laboratories,playing a pivotal role in fields such as biomedicine,environmental monitoring,food safety,and materials science.However,domestic autosampler enterprises are facing formidable challenges,confronted by the technological barriers and brand dominance of international giants,as well as increasingly fierce homogeneous competition in the domestic market.This article aims to thoroughly analyze the current market landscape and,based on seven key dimensions—strategic positioning,product technology,sales channels,brand building,service and support,supply chain optimization,and talent development—propose a series of effective market-winning strategies.This will provide theoretical guidance and practical reference for domestic autosampler enterprises to achieve breakthroughs and sustainable development amidst fierce market competition.
基金supported by the Fonds Wetenschappelijk Onderzoek(FWO)[grant number 1S16824N]the Cost Action CLEANFOREST[E-COST-GRANT-CA21138-c4968ca1].
文摘Droughts pose significant threats to forest ecosystems globally.Effective forest management strategies,adapted to local conditions,are needed to mitigate negative drought impacts.One proposed strategy is competition reduction to increase water availability and,as a result,alleviate drought stress.This study investigates the effect of competition intensity on drought stress and tree growth in European beech(Fagus sylvatica)and pedunculate oak(Quercus robur).We deployed 72 point dendrometers,placed along a competition intensity gradient,in National Park Brabantse Wouden(Belgium),to measure daily minimum tree water deficit(TWD_(min))as a drought stress proxy and daily radial growth at tree level.Our results revealed species-dependent effects of competition intensity(CI).For European beech,competition reductions positively influenced growth and alleviated(1<CI<2)or aggravated(CI<0.5)drought stress.For pedunculate oak,competition intensity did not affect drought stress or growth along the investigated gradient.Environmental variables consistently affected TWDmin and growth of both species.Precipitation reduced TWDmin and increased growth,while vapor pressure deficit led to opposite trends.Thus,environmental conditions and competition can play a critical role in forest dynamics,especially in light of climate change.However,reducing competition through increased management efforts does not seem to be a one-size-fits-all solution to alleviating drought stress.Additionally,there seems to be a trade-off between reducing drought stress and improving tree growth in European beech:tree growth continuously benefited from competition reductions,while under low competition(CI<0.5)drought stress increased.Revisiting or reviving long-term thinning intensity trials encompassing various regions,species,and soil types will be needed to gain comprehensive insights into mitigating drought stress through management interventions under different local stand conditions.
文摘The deep sea holds vital resources and spatial potential for future human survival and development,reflecting the common interests and concerns of all mankind.Amidst unprecedented global transformations in a hundred years,the deep sea has emerged as a critical area of international competition and serves as a new frontier for resource extraction,a strategic space for military competition,and a contested space for great power rivalry and rule-making.
基金supported by the National Natural Science Foundation of China(Grant Number 61573264).
文摘As a complicated optimization problem,parallel batch processing machines scheduling problem(PBPMSP)exists in many real-life manufacturing industries such as textiles and semiconductors.Machine eligibility means that at least one machine is not eligible for at least one job.PBPMSP and scheduling problems with machine eligibility are frequently considered;however,PBPMSP with machine eligibility is seldom explored.This study investigates PBPMSP with machine eligibility in fabric dyeing and presents a novel shuffled frog-leaping algorithm with competition(CSFLA)to minimize makespan.In CSFLA,the initial population is produced in a heuristic and random way,and the competitive search of memeplexes comprises two phases.Competition between any two memeplexes is done in the first phase,then iteration times are adjusted based on competition,and search strategies are adjusted adaptively based on the evolution quality of memeplexes in the second phase.An adaptive population shuffling is given.Computational experiments are conducted on 100 instances.The computational results showed that the new strategies of CSFLA are effective and that CSFLA has promising advantages in solving the considered PBPMSP.
