<div style="text-align:justify;"> This integrative review aimed to investigate factors relating to end-of-life care of nurses. The review was conducted according to PICo (Participant, area of Interest,...<div style="text-align:justify;"> This integrative review aimed to investigate factors relating to end-of-life care of nurses. The review was conducted according to PICo (Participant, area of Interest, and Context). Keywords identified were: “nurse” AND “end-of-life care” (“dyingcare” OR “‘deathcare”, OR “near end stage of life care” OR “palliative care” OR “hospice care” OR “comfortable care in near death” OR “quality of dying patients care”), AND “nurses”. The database searched through PubMed, ProQuest, Google Scholar, Web of Science and SCOPUS. The searching inclusion criteria were limited to English and Chinese language studies about nurses’ end-of-life care from 2010 to 2019, yielding 258 English language articles and 2Chinese language articles. Results: A total of fifteen articles were selected based on inclusion criteria. Two subjects were obtained from the results that related to nurses’ care during the process of end of life: 1) Nurses’ demographic factors;and 2) Modifiable factors. Nurses’ demographic factors were age, years of work experience, level of education and experience of the death of a family member/friend. Modifiable factors included knowledge, attitude, confidence, relationship, environment and resources, communication, nursing activities, philosophy and culture of care, skills and training. These factors were explored in various areas and majority of the studies had been conducted in public government hospitals. Conclusion: The major power ability of care was observed in nurses who acted the significant part in caring for the terminally ill during the dying process. Caring for dying patients was related to many factors which could affect the fabric of nursing care at the end stage of life. The elements found in this review could lead to recommendations with implications for nursing practice so as to improve and enhance end-of-life care. Some factors could be considered like predictors affecting nursing practice for chronical ill patients in further research. In addition, nurses’ tranquility care in community hospitals should be more focused. </div>展开更多
Higher education and research in Ethiopia is going through a decisive phase of reform and expansion. As a system it is increasingly required to respond and gear adequately to the development needs of the society and t...Higher education and research in Ethiopia is going through a decisive phase of reform and expansion. As a system it is increasingly required to respond and gear adequately to the development needs of the society and the country. This change is taking place through a government-led radical review of the system’s status and challenges, and by devising mechanisms of consensus building, as well as ownership and overcoming the resistance to change. Higher education and research institutions of Bahir Dar and Gondar Universities and ARARI, in Ethiopia are not satisfactorily responsive to rural transformation in addressing problems of small-scale farmers. This calls for responsive education and research that addresses farmers’ constraints. Thus, to survey the suitability/appropriateness of the current training programmes of higher education and research institutions to address the actual problems of farmers is of paramount importance. To this effect, tools such as interview guide, checklist and questionnaires were put to use for data collection. Primary data was collected from observation, focus group discussions and key informant interviews. Descriptive statistics for quantitative data and triangulation for qualitative data were the prime techniques for data analysis. The result of the study shows that university heads, instructors, students, research heads, researchers and employees rated the suggested mechanisms, namely “inviting speakers from industries and farming community”, “visiting vip lecturers” and “special entrepreneurial project”, as the top most important for ensuring training and research closely to the reality in the society of Amhara region in facilitating agricultural growth and rural transformation. Besides, employers and farmers responded that fresh graduates are deficient with relevant technical skills because of less emphasis on experiential learning on higher education. Therefore, the curriculum for the training should give much weight to incorporate these suggested mechanisms and the higher institutions curriculum should be arranged in such a way that the trainees could obtain appropriate technical know-how.展开更多
Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural cry...Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural crystal products,man-made gem and other展开更多
Currently the project'Development and commercia application of FCC catalyst for boosting gasoline yield'jointly undertaken by the SINOPEC Research Institute of Petroleum Processing(RIPP),the SINOPEC Yanshan Br...Currently the project'Development and commercia application of FCC catalyst for boosting gasoline yield'jointly undertaken by the SINOPEC Research Institute of Petroleum Processing(RIPP),the SINOPEC Yanshan Branch Co.and the Branch of SINOPEC Catalyst Company has passed the appraisal.The catalyst aimed at boosting展开更多
This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute....This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute. When teaching the second-year students, I have often been asked this awkward question: "What do you think is the correct way to study English?" It took me quite a time to answer it. Now after many years of teaching I think I have some ideas on this subject.展开更多
At the end of December 2023,the Central Conference on Work Relating to Foreign Affairs was successfully held.General Secretary Xi Jinping delivered an important address at the conference,in which he presented a compre...At the end of December 2023,the Central Conference on Work Relating to Foreign Affairs was successfully held.General Secretary Xi Jinping delivered an important address at the conference,in which he presented a comprehensive review of the historic achievements and valuable experience of major-country diplomacy with Chinese characteristics in the new era.展开更多
The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical m...The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical model height.The Taguchi method was employed to establish the correlations between process parameter combinations and multi-objective characterization of metal deposition morphology(height error and roughness).Results show that using the signal-to-noise ratio and grey relational analysis,the optimal parameter combination for multi-layer and multi-pass deposition is determined as follows:laser power of 800 W,powder feeding rate of 0.3 r/min,step distance of 1.6 mm,and scanning speed of 20 mm/s.Subsequently,a Genetic Bayesian-back propagation(GB-BP)network is constructed to predict multi-objective responses.Compared with the traditional back propagation network,the GB-back propagation network improves the prediction accuracy of height error and surface roughness by 43.14%and 71.43%,respectively.This network can accurately predict the multi-objective characterization of morphological quality of multi-layer and multi-pass metal deposited parts.展开更多
The year 2026 marks the 70th anniversary of the establishment of diplomatic relations between China and African countries.It also marks the launch of the China-Africa Year of People-to-People Exchanges.At this pivotal...The year 2026 marks the 70th anniversary of the establishment of diplomatic relations between China and African countries.It also marks the launch of the China-Africa Year of People-to-People Exchanges.At this pivotal juncture linking past achievements with future development,Wang Yi,member of the Political Bureau of the Communist Party of China Central Committee and foreign minister,continued the longstanding diplomatic tradition under which the Chinese foreign minister makes Africa the destination of the first overseas visit of the year,a practice upheld for 36 consecutive years,underscoring the stability,continuity and sincerity of China’s policy towards Africa.展开更多
AN INEQUALITY RELATING THE ORDER, MAXIMUM DEGREE, DIAMETER AND CONNECTIVITY OF A STRONGLY CONNECTED DIGRAPH We prove that if there is a strongly connected digraph of order n, maximum degree d,diameter k and connectivi...AN INEQUALITY RELATING THE ORDER, MAXIMUM DEGREE, DIAMETER AND CONNECTIVITY OF A STRONGLY CONNECTED DIGRAPH We prove that if there is a strongly connected digraph of order n, maximum degree d,diameter k and connectivity C, then n≤c(d_k-d)/(d-1)M+d+1. It improves the previous knownresults, and it, in fact, is the best possible for several interesting cases. A similar result for arcconnectivity is also established.展开更多
Understory bryophytes play unique and disproportionately important roles in water retention,biogeochemical cycling,and biodiversity conservation,and serve as bioindicators of environmental health in forest ecosystems....Understory bryophytes play unique and disproportionately important roles in water retention,biogeochemical cycling,and biodiversity conservation,and serve as bioindicators of environmental health in forest ecosystems.However,biogeographical research on the biomass of forest bryophytes is inadequately studied and has been limited to elevational gradients.We conducted a systematic cross-regional survey of bryophyte biomass across 413 forest sites in Sichuan Province,China.We analyzed how each environmental variable,including climatic and atmospheric factors,overstory covers,and soil nutrients,relates to bryophyte biomass and quantified their relative contributions.The results indicate that,largely similar to previous local investigations and experiments,at a large scale,bryophytes are abundant in forests with lower temperature,nitrogen deposition,vapor pressure deficit,and tree and herb covers,as well as higher light availability.Moreover,bryophyte biomass is positively associated with soil carbon and nitrogen content.These environmental variables are closely related and jointly influence bryophyte biomass,with mean annual temperature being the most significant factor(accounting for 83%of the relative contribution).The biogeographical patterns of bryophyte biomass contribute to deepening our understanding of their adaptations to multiple environmental variables and enable us to predict their responses to global climate change.These patterns also provide essential evidence for establishing more accurate terrestrial vegetation ecosystem models.展开更多
On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WIT...On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WITH a population of approximately one million,Cyprus is a small country compared to China,which is home to more than 1.4 billion people.展开更多
The quantitative relationship between modern pollen and vegetation provides a critical foundation for reconstructing past vegetation,with relative pollen productivity(RPP)serving as a key calibration parameter.However...The quantitative relationship between modern pollen and vegetation provides a critical foundation for reconstructing past vegetation,with relative pollen productivity(RPP)serving as a key calibration parameter.However,in subtropical evergreen broadleaved forests(SEBFs)in China,RPP studies remain scarce,and the impact of human disturbances on RPP estimates has yet to be adequately assessed,limiting the accuracy of quantitative palaeovegetation reconstructions.This study was conducted in Dinghu Mountain Nature Reserve and its surrounding areas in Zhaoqing,Guangdong Province,and included 31 sampling sites.We performed pollen analysis alongside detailed vegetation surveys and utilized ERV submodel 2 and Prentice’s model to estimate the RPP of 9 common plant taxa in the southern SEBFs.There was a particular focus on evaluating the interference effects of bamboo plantations on the estimation of RPP.The results indicate that bamboo within the family Poaceae contributes minimally to surface soil Poaceae pollen because of its unique flowering characteristics,such as long flowering cycles and monocarpic reproduction.The incorporation of bamboo into the Poaceae vegetation coverage in the analysis led to excessively high RPP values for the other taxa.When bamboo coverage was removed from the Poaceae family,the recalculated RPP values aligned closely with those reported in previous studies.The RPP values,ranked from highest to lowest,were as follows:Castanopsis(12.33±0.03)>Araliaceae(1.60±0.03)>Mallotus(1.53±0.26)>Pinus(1.47±0.03)>Rosaceae(1.07±0.02)>Poaceae(1±0)>Euphorbiaceae(0.44±0.03)>Anacardiaceae(0.26±0.03)>Theaceae(0.15±0).Notably,the RPP values for Mallotus,Araliaceae,Theaceae,and Euphorbiaceae represent the first estimates for China’s subtropical region.Differences between certain RPP estimates and those of previous studies may be attributed to factors such as species composition,vegetation structure,and model selection.The findings of this study highlight that due to the widespread distribution of artificial bamboo forests in China’s subtropical regions,future RPP studies should carefully consider the influence of Poaceae.This consideration is essential for improving the accuracy of the application of fossil pollen for quantitative paleo-vegetation reconstruction in these regions.展开更多
The composition−property relationship of 18 quaternary high entropy diborides(HEBs)consisting of boron and IVB,VB and VIB transition metals(TM)was investigated using first-principles calculations.A valence electron co...The composition−property relationship of 18 quaternary high entropy diborides(HEBs)consisting of boron and IVB,VB and VIB transition metals(TM)was investigated using first-principles calculations.A valence electron concentration−relative electronegativity(VEC−REN)composite descriptor was developed to effectively predict the mechanical properties of HEBs.The results demonstrate that with a fixed VEC,the rise of the REN makes HEBs harder but more brittle when the electronegativity of doped TM atoms is lower than that of boron atoms.However,HEBs become softer and more ductile as REN increases if the doped TM atoms have higher electronegativity than boron atoms.The VEC−REN composite descriptor can accurately classify and predict the mechanical properties of HEBs with different components,which provides important theoretical guidance for the rapid design and development of novel high-entropy ceramic materials.展开更多
The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we condu...The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we conducted a series of triaxial tests on calcareous sand with varying Dri and stress paths,examining particle breakage and critical state behavior.Key findingsinclude:(1)At a constant stress ratio(η),B follows a hyperbolic relationship with mean effective stress(p'),and for a given p',B increases proportionally withη;(2)The critical state line(CSL)moves downward with increasing Dri,whereas the critical state friction angle(φcs)decreases with increasing B.Based on these findings,we propose a unifiedbreakage evolution model to quantify particle breakage in calcareous sand under various loading conditions.Integrating this model with the Normal Consolidation Line(NCL)and CSL equations,we successfully simulate the steepening of NCL and CSL slopes as B increases with the onset of particle breakage.Furthermore,we quantitatively evaluate the effect of B onφcs.Finally,within the framework of Critical State Soil Mechanics and Hypoplasticity theory,we develop a hypoplastic model incorporating B and Dri.The model is validated through strong agreement with experimental results across various initial relative densities,stress paths and drainage conditions.展开更多
Bread wheat(Triticum aestivum L.)is a staple hexaploid crop with numerous wild relatives.However,domestication and modern breeding have significantly narrowed its genetic diversity,diminishing its capacity to adapt to...Bread wheat(Triticum aestivum L.)is a staple hexaploid crop with numerous wild relatives.However,domestication and modern breeding have significantly narrowed its genetic diversity,diminishing its capacity to adapt to climate change.Wild relatives of wheat serve as a vital reservoir of genetic diversity,offering traits thatenhance its resistance to various biotic and abiotic stresses.Over recent decades,remarkable progress has been made in utilizing superior genes from wild relatives to bolster wheat's defenses against diseases and pests,though the exploration of genes conferring abiotic stress tolerance has lagged behind.In this review,we summarize key advancements in the utilization of wild relatives for wheat enhancement over the past century,emphasizing both theoretical and technological innovations.Furthermore,we evaluate the potential contributions of wild relatives to address production challenges posed by climate change.We also explore strategies for isolating superior genes and developing prebreeding germplasm to support the future development of climate-resilient wheat varieties.展开更多
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb...Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.展开更多
Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa&#...Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa's human capital and accelerating its structural transformation and modernization process.This paper employs“demand–supply–adaptation”as its core analytical framework and aims to systematically explore how the educational cooperation between China and Africa can serve Africa's goal of modernization more precisely and effectively.First,through reviewing and analyzing the domestic and international research literature,this paper clarifies the focus,paradigms,and shortcomings of existing research,identifying the knowledge contribution of this study.Second,utilizing detailed macro-level data,case studies,and comparative research methods,it comprehensively presents the multidimensional status,structural characteristics,and development trends of China–Africa educational cooperation in areas such as student exchanges,cooperative education,vocational and technical training,language and cultural exchange,and emerging digital education.This paper also deeply analyzes the pressing and specific demands placed on the education system by Africa's modernization development across key dimensions like economic diversification,industrialization,agricultural modernization,social governance upgrading,and digital transformation.Third,based on the cooperative principle of“Africa's needs and China's strengths,”this paper innovatively proposes systematic countermeasures and suggestions for constructing new,multi-level,high-quality,sustainable,and future-oriented pathways for China–Africa educational cooperation:(a)promoting the strategic focus of cooperation to extend from“hard infrastructure”support to empowering“soft infrastructure”;(b)deepening the integration of industry and education and school–enterprise collaboration to precisely align with Africa's industrial development needs;vigorously developing digital education and jointly building a smart education ecosystem to help Africa bridge the digital divide;(c)improving an evidence-based,third-party evaluation system for cooperative effectiveness and a full-process quality assurance system;and(d)promoting the collaborative participation of multiple actors including governments,schools,enterprises,think tanks,and social organizations to build a new cooperative pattern of coconstruction,co-governance,and shared benefits.展开更多
According to the 2024 global cancer data from GLOBOCAN,liver cancer ranks the 6th most common malignancy and the 3rd leading cause of cancer-related mortality worldwide[1].Among these cases,hepatocellular carcinoma(HC...According to the 2024 global cancer data from GLOBOCAN,liver cancer ranks the 6th most common malignancy and the 3rd leading cause of cancer-related mortality worldwide[1].Among these cases,hepatocellular carcinoma(HCC)accounts for approximately 85%−90%[2,3].Its incidence and mortality rates remain persistently high worldwide.However,China has the highest incidence and mortality rates of the disease in the world[4].And the majority of patients are diagnosed at intermediate or advanced stages.Thus,identifying novel tumor biomarkers for early detection and implementing precision therapy has long been a key focus of research.展开更多
Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mo...Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mortality.Although organis m-wide deterioration is observed during aging,organs with high metabolic demand,such as the brain,are more vulnerable.展开更多
文摘<div style="text-align:justify;"> This integrative review aimed to investigate factors relating to end-of-life care of nurses. The review was conducted according to PICo (Participant, area of Interest, and Context). Keywords identified were: “nurse” AND “end-of-life care” (“dyingcare” OR “‘deathcare”, OR “near end stage of life care” OR “palliative care” OR “hospice care” OR “comfortable care in near death” OR “quality of dying patients care”), AND “nurses”. The database searched through PubMed, ProQuest, Google Scholar, Web of Science and SCOPUS. The searching inclusion criteria were limited to English and Chinese language studies about nurses’ end-of-life care from 2010 to 2019, yielding 258 English language articles and 2Chinese language articles. Results: A total of fifteen articles were selected based on inclusion criteria. Two subjects were obtained from the results that related to nurses’ care during the process of end of life: 1) Nurses’ demographic factors;and 2) Modifiable factors. Nurses’ demographic factors were age, years of work experience, level of education and experience of the death of a family member/friend. Modifiable factors included knowledge, attitude, confidence, relationship, environment and resources, communication, nursing activities, philosophy and culture of care, skills and training. These factors were explored in various areas and majority of the studies had been conducted in public government hospitals. Conclusion: The major power ability of care was observed in nurses who acted the significant part in caring for the terminally ill during the dying process. Caring for dying patients was related to many factors which could affect the fabric of nursing care at the end stage of life. The elements found in this review could lead to recommendations with implications for nursing practice so as to improve and enhance end-of-life care. Some factors could be considered like predictors affecting nursing practice for chronical ill patients in further research. In addition, nurses’ tranquility care in community hospitals should be more focused. </div>
文摘Higher education and research in Ethiopia is going through a decisive phase of reform and expansion. As a system it is increasingly required to respond and gear adequately to the development needs of the society and the country. This change is taking place through a government-led radical review of the system’s status and challenges, and by devising mechanisms of consensus building, as well as ownership and overcoming the resistance to change. Higher education and research institutions of Bahir Dar and Gondar Universities and ARARI, in Ethiopia are not satisfactorily responsive to rural transformation in addressing problems of small-scale farmers. This calls for responsive education and research that addresses farmers’ constraints. Thus, to survey the suitability/appropriateness of the current training programmes of higher education and research institutions to address the actual problems of farmers is of paramount importance. To this effect, tools such as interview guide, checklist and questionnaires were put to use for data collection. Primary data was collected from observation, focus group discussions and key informant interviews. Descriptive statistics for quantitative data and triangulation for qualitative data were the prime techniques for data analysis. The result of the study shows that university heads, instructors, students, research heads, researchers and employees rated the suggested mechanisms, namely “inviting speakers from industries and farming community”, “visiting vip lecturers” and “special entrepreneurial project”, as the top most important for ensuring training and research closely to the reality in the society of Amhara region in facilitating agricultural growth and rural transformation. Besides, employers and farmers responded that fresh graduates are deficient with relevant technical skills because of less emphasis on experiential learning on higher education. Therefore, the curriculum for the training should give much weight to incorporate these suggested mechanisms and the higher institutions curriculum should be arranged in such a way that the trainees could obtain appropriate technical know-how.
文摘Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural crystal products,man-made gem and other
文摘Currently the project'Development and commercia application of FCC catalyst for boosting gasoline yield'jointly undertaken by the SINOPEC Research Institute of Petroleum Processing(RIPP),the SINOPEC Yanshan Branch Co.and the Branch of SINOPEC Catalyst Company has passed the appraisal.The catalyst aimed at boosting
文摘This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute. When teaching the second-year students, I have often been asked this awkward question: "What do you think is the correct way to study English?" It took me quite a time to answer it. Now after many years of teaching I think I have some ideas on this subject.
文摘At the end of December 2023,the Central Conference on Work Relating to Foreign Affairs was successfully held.General Secretary Xi Jinping delivered an important address at the conference,in which he presented a comprehensive review of the historic achievements and valuable experience of major-country diplomacy with Chinese characteristics in the new era.
基金National Natural Science Foundation of China(52175237)。
文摘The key parameters that characterize the morphological quality of multi-layer and multi-pass metal laser deposited parts are the surface roughness and the error between the actual printing height and the theoretical model height.The Taguchi method was employed to establish the correlations between process parameter combinations and multi-objective characterization of metal deposition morphology(height error and roughness).Results show that using the signal-to-noise ratio and grey relational analysis,the optimal parameter combination for multi-layer and multi-pass deposition is determined as follows:laser power of 800 W,powder feeding rate of 0.3 r/min,step distance of 1.6 mm,and scanning speed of 20 mm/s.Subsequently,a Genetic Bayesian-back propagation(GB-BP)network is constructed to predict multi-objective responses.Compared with the traditional back propagation network,the GB-back propagation network improves the prediction accuracy of height error and surface roughness by 43.14%and 71.43%,respectively.This network can accurately predict the multi-objective characterization of morphological quality of multi-layer and multi-pass metal deposited parts.
文摘The year 2026 marks the 70th anniversary of the establishment of diplomatic relations between China and African countries.It also marks the launch of the China-Africa Year of People-to-People Exchanges.At this pivotal juncture linking past achievements with future development,Wang Yi,member of the Political Bureau of the Communist Party of China Central Committee and foreign minister,continued the longstanding diplomatic tradition under which the Chinese foreign minister makes Africa the destination of the first overseas visit of the year,a practice upheld for 36 consecutive years,underscoring the stability,continuity and sincerity of China’s policy towards Africa.
基金This project is supported by the National Natural Science Foundation of China
文摘AN INEQUALITY RELATING THE ORDER, MAXIMUM DEGREE, DIAMETER AND CONNECTIVITY OF A STRONGLY CONNECTED DIGRAPH We prove that if there is a strongly connected digraph of order n, maximum degree d,diameter k and connectivity C, then n≤c(d_k-d)/(d-1)M+d+1. It improves the previous knownresults, and it, in fact, is the best possible for several interesting cases. A similar result for arcconnectivity is also established.
基金supported by the National Natural Science Foundation of China(No.31600316)the Sichuan Science and Technology Program(2023NSFSC0198)。
文摘Understory bryophytes play unique and disproportionately important roles in water retention,biogeochemical cycling,and biodiversity conservation,and serve as bioindicators of environmental health in forest ecosystems.However,biogeographical research on the biomass of forest bryophytes is inadequately studied and has been limited to elevational gradients.We conducted a systematic cross-regional survey of bryophyte biomass across 413 forest sites in Sichuan Province,China.We analyzed how each environmental variable,including climatic and atmospheric factors,overstory covers,and soil nutrients,relates to bryophyte biomass and quantified their relative contributions.The results indicate that,largely similar to previous local investigations and experiments,at a large scale,bryophytes are abundant in forests with lower temperature,nitrogen deposition,vapor pressure deficit,and tree and herb covers,as well as higher light availability.Moreover,bryophyte biomass is positively associated with soil carbon and nitrogen content.These environmental variables are closely related and jointly influence bryophyte biomass,with mean annual temperature being the most significant factor(accounting for 83%of the relative contribution).The biogeographical patterns of bryophyte biomass contribute to deepening our understanding of their adaptations to multiple environmental variables and enable us to predict their responses to global climate change.These patterns also provide essential evidence for establishing more accurate terrestrial vegetation ecosystem models.
文摘On the threshold of 55 years of diplomatic relations,Cyprus and China stand to gain significantly by deepening their cooperation in trade,tourism,and green technology,guided by mutual respect and shared principles.WITH a population of approximately one million,Cyprus is a small country compared to China,which is home to more than 1.4 billion people.
基金supported by the National Natural Science Foundation of China(Grant Nos.42407595&41630753)the National Key Research and Development Program of China(Grant No.2022YFF0801501).
文摘The quantitative relationship between modern pollen and vegetation provides a critical foundation for reconstructing past vegetation,with relative pollen productivity(RPP)serving as a key calibration parameter.However,in subtropical evergreen broadleaved forests(SEBFs)in China,RPP studies remain scarce,and the impact of human disturbances on RPP estimates has yet to be adequately assessed,limiting the accuracy of quantitative palaeovegetation reconstructions.This study was conducted in Dinghu Mountain Nature Reserve and its surrounding areas in Zhaoqing,Guangdong Province,and included 31 sampling sites.We performed pollen analysis alongside detailed vegetation surveys and utilized ERV submodel 2 and Prentice’s model to estimate the RPP of 9 common plant taxa in the southern SEBFs.There was a particular focus on evaluating the interference effects of bamboo plantations on the estimation of RPP.The results indicate that bamboo within the family Poaceae contributes minimally to surface soil Poaceae pollen because of its unique flowering characteristics,such as long flowering cycles and monocarpic reproduction.The incorporation of bamboo into the Poaceae vegetation coverage in the analysis led to excessively high RPP values for the other taxa.When bamboo coverage was removed from the Poaceae family,the recalculated RPP values aligned closely with those reported in previous studies.The RPP values,ranked from highest to lowest,were as follows:Castanopsis(12.33±0.03)>Araliaceae(1.60±0.03)>Mallotus(1.53±0.26)>Pinus(1.47±0.03)>Rosaceae(1.07±0.02)>Poaceae(1±0)>Euphorbiaceae(0.44±0.03)>Anacardiaceae(0.26±0.03)>Theaceae(0.15±0).Notably,the RPP values for Mallotus,Araliaceae,Theaceae,and Euphorbiaceae represent the first estimates for China’s subtropical region.Differences between certain RPP estimates and those of previous studies may be attributed to factors such as species composition,vegetation structure,and model selection.The findings of this study highlight that due to the widespread distribution of artificial bamboo forests in China’s subtropical regions,future RPP studies should carefully consider the influence of Poaceae.This consideration is essential for improving the accuracy of the application of fossil pollen for quantitative paleo-vegetation reconstruction in these regions.
基金the National Natural Science Foundation of China (Nos. 52071179, 52271033)the Key Program of National Natural Science Foundation of China (No. 51931003)+2 种基金the Natural Science Foundation of Jiangsu Province, China (No. BK20221493)the Jiangsu Province Leading Edge Technology Basic Research Major Project, China (No. BK20222014)the Foundation of “Qinglan Project” for Colleges and Universities in Jiangsu Province, China。
文摘The composition−property relationship of 18 quaternary high entropy diborides(HEBs)consisting of boron and IVB,VB and VIB transition metals(TM)was investigated using first-principles calculations.A valence electron concentration−relative electronegativity(VEC−REN)composite descriptor was developed to effectively predict the mechanical properties of HEBs.The results demonstrate that with a fixed VEC,the rise of the REN makes HEBs harder but more brittle when the electronegativity of doped TM atoms is lower than that of boron atoms.However,HEBs become softer and more ductile as REN increases if the doped TM atoms have higher electronegativity than boron atoms.The VEC−REN composite descriptor can accurately classify and predict the mechanical properties of HEBs with different components,which provides important theoretical guidance for the rapid design and development of novel high-entropy ceramic materials.
基金support to this study from the National Natural Science Foundation of China,NSFC(Grant No.52278367)The Belt and Road Special Foundation of the National Key Laboratory ofWater Disaster Prevention(Grant No.2024nkms08).
文摘The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we conducted a series of triaxial tests on calcareous sand with varying Dri and stress paths,examining particle breakage and critical state behavior.Key findingsinclude:(1)At a constant stress ratio(η),B follows a hyperbolic relationship with mean effective stress(p'),and for a given p',B increases proportionally withη;(2)The critical state line(CSL)moves downward with increasing Dri,whereas the critical state friction angle(φcs)decreases with increasing B.Based on these findings,we propose a unifiedbreakage evolution model to quantify particle breakage in calcareous sand under various loading conditions.Integrating this model with the Normal Consolidation Line(NCL)and CSL equations,we successfully simulate the steepening of NCL and CSL slopes as B increases with the onset of particle breakage.Furthermore,we quantitatively evaluate the effect of B onφcs.Finally,within the framework of Critical State Soil Mechanics and Hypoplasticity theory,we develop a hypoplastic model incorporating B and Dri.The model is validated through strong agreement with experimental results across various initial relative densities,stress paths and drainage conditions.
基金supported by the Biological Breeding-National Science and Technology Major Project(2023ZD04071)the National Key Research and Development Program of China(2023YFF1000600)and the National Natural Science Foundation of China(32272084,32372089,and 31971887).
文摘Bread wheat(Triticum aestivum L.)is a staple hexaploid crop with numerous wild relatives.However,domestication and modern breeding have significantly narrowed its genetic diversity,diminishing its capacity to adapt to climate change.Wild relatives of wheat serve as a vital reservoir of genetic diversity,offering traits thatenhance its resistance to various biotic and abiotic stresses.Over recent decades,remarkable progress has been made in utilizing superior genes from wild relatives to bolster wheat's defenses against diseases and pests,though the exploration of genes conferring abiotic stress tolerance has lagged behind.In this review,we summarize key advancements in the utilization of wild relatives for wheat enhancement over the past century,emphasizing both theoretical and technological innovations.Furthermore,we evaluate the potential contributions of wild relatives to address production challenges posed by climate change.We also explore strategies for isolating superior genes and developing prebreeding germplasm to support the future development of climate-resilient wheat varieties.
基金Supported by the Science and Technology Program of Guizhou Province(Grant No.QKHJC QN[2025]362)the National Natural Science Foundation of China(Grant No.12361005).
文摘Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.
文摘Educational cooperation,as the cornerstone and vanguard of people-to-people exchanges and practical cooperation between China and Africa,holds irreplaceable strategic significance for enhancing the quality of Africa's human capital and accelerating its structural transformation and modernization process.This paper employs“demand–supply–adaptation”as its core analytical framework and aims to systematically explore how the educational cooperation between China and Africa can serve Africa's goal of modernization more precisely and effectively.First,through reviewing and analyzing the domestic and international research literature,this paper clarifies the focus,paradigms,and shortcomings of existing research,identifying the knowledge contribution of this study.Second,utilizing detailed macro-level data,case studies,and comparative research methods,it comprehensively presents the multidimensional status,structural characteristics,and development trends of China–Africa educational cooperation in areas such as student exchanges,cooperative education,vocational and technical training,language and cultural exchange,and emerging digital education.This paper also deeply analyzes the pressing and specific demands placed on the education system by Africa's modernization development across key dimensions like economic diversification,industrialization,agricultural modernization,social governance upgrading,and digital transformation.Third,based on the cooperative principle of“Africa's needs and China's strengths,”this paper innovatively proposes systematic countermeasures and suggestions for constructing new,multi-level,high-quality,sustainable,and future-oriented pathways for China–Africa educational cooperation:(a)promoting the strategic focus of cooperation to extend from“hard infrastructure”support to empowering“soft infrastructure”;(b)deepening the integration of industry and education and school–enterprise collaboration to precisely align with Africa's industrial development needs;vigorously developing digital education and jointly building a smart education ecosystem to help Africa bridge the digital divide;(c)improving an evidence-based,third-party evaluation system for cooperative effectiveness and a full-process quality assurance system;and(d)promoting the collaborative participation of multiple actors including governments,schools,enterprises,think tanks,and social organizations to build a new cooperative pattern of coconstruction,co-governance,and shared benefits.
基金supported by a grant from the Central Level Public Welfare Research Institutes Basic Research Expenses of Chinese Academy of Medical Sciences(No.2023-RW320-05)。
文摘According to the 2024 global cancer data from GLOBOCAN,liver cancer ranks the 6th most common malignancy and the 3rd leading cause of cancer-related mortality worldwide[1].Among these cases,hepatocellular carcinoma(HCC)accounts for approximately 85%−90%[2,3].Its incidence and mortality rates remain persistently high worldwide.However,China has the highest incidence and mortality rates of the disease in the world[4].And the majority of patients are diagnosed at intermediate or advanced stages.Thus,identifying novel tumor biomarkers for early detection and implementing precision therapy has long been a key focus of research.
文摘Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mortality.Although organis m-wide deterioration is observed during aging,organs with high metabolic demand,such as the brain,are more vulnerable.
