According to the related data of A-share listed companies in 2009-2013,through extension model based on Basu's surplus - the stock return rate model ,this paper studies that the debt maturity structure influences on ...According to the related data of A-share listed companies in 2009-2013,through extension model based on Basu's surplus - the stock return rate model ,this paper studies that the debt maturity structure influences on accounting conservatism. The empirical study finds that the amount of debt affects significantly the prudence,that is,the greater the amount of the debt contract con- cluded, the stronger role of accounting conservatism is ; Debt maturity have significant relationship with accounting conservatism. For the shorter debt maturity, the enterprise is easier to choose more prudent accounting policy, and when the period is longer, accounting conservatism is relatively weaker.展开更多
As one of the representative Chinese writers who was born in the 1970s,Qiao Ye's writing exhibits considerable diversity and varied understandings of literature across genres.In her full-length novels,Qiao Ye is e...As one of the representative Chinese writers who was born in the 1970s,Qiao Ye's writing exhibits considerable diversity and varied understandings of literature across genres.In her full-length novels,Qiao Ye is exceptionally innovative and exploratory,and each novel is distinct in subject matter and style.However,her medium-length and short stories tend to be more conservative,characterized by a simple and natural style,imbued with the charm of literary tradition.This artistic stance in writing style is different from other writers and unique to Qiao Ye,which is not only indicative of her vivid artistic individuality but also holds value for further research into creative writing and stylistics.展开更多
The culture wars that simmer within any nation may have been escalating recently;but regardless of their national settings or milieus,many of these wars are informed by two opposing paradigms of culture.This paper ana...The culture wars that simmer within any nation may have been escalating recently;but regardless of their national settings or milieus,many of these wars are informed by two opposing paradigms of culture.This paper analyzes two of these leading paradigms,designated here as Regressivism and Progressivism.Other theorists have long chronicled the differing strengths and weaknesses of these paradigms,taking the former as expressing more conservative,traditional,and nationalistic values,and the latter as expressing more liberal,pluralistic,and cosmopolitan values.Going beyond these perennial distinctions,I argue that Progressivism is more benign and beneficial than the former-by meeting basic human needs better and supporting more effective adaptation to changing exigencies.I also argue that Progressivism does not express merely subjective or relativistic preferences and values,but objectively preferable and quantifiable ones,that benefit not only our personal lives more but also our global village and communal lives more.展开更多
This paper investigates the factors affecting the conservatism of accounting reports at the market-level and firm-level. At the market-level, law and institutional factors explain conservatism, while at the firm-level...This paper investigates the factors affecting the conservatism of accounting reports at the market-level and firm-level. At the market-level, law and institutional factors explain conservatism, while at the firm-level contracting is the driver. We predict and observe that while both levels jointly affect conservatism, it is firm-level factors that play a dominant role. The conclusion suggests that it is more effective to improve the quality of accounting reports by motivating the firm's own demand rather than through listing in a developed capital market.展开更多
Based on signaling and gender discrimination theory, we examine whether chief financial officer(CFO) gender matters to bank–firm relationships and the designing of collateral clauses in bank loan contracting, and exp...Based on signaling and gender discrimination theory, we examine whether chief financial officer(CFO) gender matters to bank–firm relationships and the designing of collateral clauses in bank loan contracting, and explore the potential path of influence. Data taken from Chinese listed companies between2009 and 2012 indicate that(1) female-CFO-led firms are less likely to obtain credit loans than male-CFO-led firms;(2) female-CFO-led borrowers are more likely to be required to provide collateral for loans than male-CFO-led borrowers; and(3) banks are more inclined to claim mortgaging collateral when lending to female-CFO-led firms and prefer to guarantee collateral when lending to male-CFO-led firms. Female-CFO-led borrowers seem to be granted more unfavorable loan terms than male-CFO-led borrowers, supporting the hypothesis that female CFOs experience credit discrimination. Further analysis reveals that regional financial development helps to alleviate lending discrimination against female CFOs. Furthermore, female CFOs in SOEs are less likely than their non-SOE counterparts to experience gender discrimination in the credit market.展开更多
Using a sample of A-share listed firms in China during the 2003–2012 period,this paper investigates the effect of accounting conservatism on trade credit,taking changes in monetary policy into account.We find that co...Using a sample of A-share listed firms in China during the 2003–2012 period,this paper investigates the effect of accounting conservatism on trade credit,taking changes in monetary policy into account.We find that corporations with higher accounting conservatism obtain more trade credit and that accounting conservatism has a greater influence on trade credit under tight monetary policy.Furthermore,the backgrounds of the supplier and customer influence the positive relationship between accounting conservatism and trade credit.This influence is more evident when a company is privately owned and has greater market power,and less evident when the supplier or customer is the controlling shareholder.展开更多
Species range expansions are crucial for understanding niche formation and the interaction with the environment.Here,we studied the bumblebee Bombus haematurus Kriechbaumer,1870,a species historically distributed from...Species range expansions are crucial for understanding niche formation and the interaction with the environment.Here,we studied the bumblebee Bombus haematurus Kriechbaumer,1870,a species historically distributed from northern Serbia through northern Iran which has very recently started expanding northwestward into Central Europe without human-mediated dispersal(i.e.,it is a natural spread).After updating the global distribution of this species,we investigated if niche shifts took place during this range expansion between newly colonized and historical areas.In addition,we have explored which climatic factors may have favored the natural range expansion of the species.Our results indicated that Bombus haematurus has colonized large territories in 7 European countries outside the historical area in the period from the 1980s to 2018,a natural expansion over an area that equals 20%of the historical distribution.In addition,this bumblebee performs generalism in flower visitation and it occurs in different habitats,although a preference for forested areas clearly emerges.The land-use associated with the species in the colonized areas is similar to the historical distribution,indicating that no major niche shifts occurred during the spread.Furthermore,in recently colonized localities,the range expansion was associated with warming temperatures during the winter and also during both queen overwintering and emergence phases.These findings document a case of natural range expansion due to environmental change rather than due to niche shifts,and specifically they suggest that warmer winters could be linked to the process of natural colonization of new areas.展开更多
This study explores the level of unconditional conservatism(UNCC)in accounting after China’s convergence with International Financial Reporting Standards(IFRS).Using the intercept of the Basu(1997)model,an overall re...This study explores the level of unconditional conservatism(UNCC)in accounting after China’s convergence with International Financial Reporting Standards(IFRS).Using the intercept of the Basu(1997)model,an overall reduction is found in UNCC under the Chinese version of IFRS.This study is the first attempt to conduct a comprehensive theoretical comparison between old and new Chinese accounting standards(CAS)in terms of UNCC.Additionally,it is the first study on the impact of convergence with IFRS,not the full adoption of IFRS,on UNCC.Finally,the study covers a relatively more extended period than most previous studies,from 1996 to 2017.展开更多
Mergers and acquisitions(M&As)are among the most important investment activities for companies,but they contain great risks.We investigate the role of accounting conservatism in M&A target selection and risk.W...Mergers and acquisitions(M&As)are among the most important investment activities for companies,but they contain great risks.We investigate the role of accounting conservatism in M&A target selection and risk.We find that for risk-averse reasons,firms with high accounting conservatism are likely to acquire profitable targets and avoid loss-making targets.When such firms acquire loss-making targets,the conservatism’s risk-control role reduces M&A risk and increases M&A performance,but only when control of the target is transferred and the acquirer has high long-term debt and low management power.Furthermore,accounting conservatism reduces risk by increasing the maturity match between cash flow and debt.Our results suggest that accounting conservatism plays not only a risk-averse role but also a riskcontrol role,providing new evidence for the usefulness of accounting conservatism in M&A decisions.展开更多
As an important building block for the synthesis of angiotensin-converting enzyme inhibitors,ethyl(R)-2-hy-droxyl-4-phenylbutanoate[(R)-HPBE]has attracted increasing attention.The key to industrial biosynthesis of(R)-...As an important building block for the synthesis of angiotensin-converting enzyme inhibitors,ethyl(R)-2-hy-droxyl-4-phenylbutanoate[(R)-HPBE]has attracted increasing attention.The key to industrial biosynthesis of(R)-HPBE is a biocatalyst that efficiently reduces ethyl 2-oxo-4-phenylbutanoate(OPBE)with high R-enantiose-lectivity.This paper proposed a strategy for identifying key residues involved in enantioselectivity control based on per-residue free energy decomposition and sequence conservatism analysis.Using this strategy,4 noncon-servative sites with high energy contribution to binding of OPBE were chosen as engineering targets,generating variant Mu27 with 99%conversion and 98%(R)ee value at substrate loading of up to 500 mmol/L.MD simu-lations suggested the higher stability and formation probability of Mu27-OPBEproR prereaction state as key rea-sons for the excellent R-enantioselectivity of Mu27 towards OPBE.The success in this study provides a viable approach for rational design of alcohol dehydrogenases with high enantioselectivity towards unnatural substrates.展开更多
The political essence of Russian conservatism is to respect the historical tradition and take a development path aligned with Russia's national conditions.Since Putin came to power,Russian conservatism has develop...The political essence of Russian conservatism is to respect the historical tradition and take a development path aligned with Russia's national conditions.Since Putin came to power,Russian conservatism has developed into the mainstream official ideology,becoming the core concept of Russia's current domestic and foreign policies.Russian conservatism is not only the guiding principle of Russia's national foreign policy,but it is also the moral banner of Russia's diplomacy,which reflects its foreign cognition and value system.Under the guidance of conservatism,Russia's foreign policy has distinct offensive features,and Russia has intensified its efforts to counter the liberal international order dominated by the West.After the escalation of the Ukraine crisis,the status of conservatism as Russia's mainstream ideology has been further consolidated,exerting a comprehensive influence on foreign policy.Against the background of extreme sanctions and isolation from the United States and the West,Russia has turned its diplomatic attention to non-Western countries,hoping to build a new international order.展开更多
Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distrib...Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China.展开更多
In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the...In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the traditional splitting methods but also can the physical feature of mutual dependence of the fast and the slow stages that are calculated separately and splittingly be kept as well. Moreover, the method owns an universality, it can be generalized to other square-conservative difference schemes, such as the implicit and complete ones and the explicit and instantaneous ones. Good time benefits can be acquired when it is applied in the numerical simulations of the monthly mean currents of the South China Sea.展开更多
Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation ...Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human activities.Using a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in Brazil.We recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil characterization.We fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary distinctiveness.We found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water availability.The inferior inselberg habitats harbor higher lineage diversity than expected by chance.Soil strongly predicted evolutionary diversity.We concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.展开更多
Theroleof nicheevolution(niche conservatism or niche divergence)in lineage diversification is a poorly studied area.The Chinese cobra Naja atra(Elapidae)has diverged into three lineages:Lineage E in eastern China,Line...Theroleof nicheevolution(niche conservatism or niche divergence)in lineage diversification is a poorly studied area.The Chinese cobra Naja atra(Elapidae)has diverged into three lineages:Lineage E in eastern China,Lineage S in southern China and Vietnam,and Lineage W in western China.However,whether the ecological niche is conserved or divergent among these three lineages is unknown.In the present study,we used ecological niche models in geographical space to study the ecological differences among lineages.We compared the niche overlap in environmental space to test niche conservatism and niche divergence.Our results showed that the three lineages of N.atra shared an ecological niche space between Lineages E and S/W,with the climatic niches of Lineages S and W representing a specialized fraction of the climatic niche of Lineage E.We speculated that the niche divergence between Lineages S and W was a consequence of geographical barriers limitinggeneflow.Ourstudyprovides evidence for lineage diversification associated with both geographical isolation and climatic niche evolution,suggesting that early niche divergence between Lineages S and W,followed by niche conservatism,causes niche divergence among lineages.展开更多
According to the advocacy group Parents,Families,and Friends of Lesbians and Gays(PFLAG),gays and lesbians are victims of hate crimes seven times as often as straight peers.The question becomes what underlying ideolog...According to the advocacy group Parents,Families,and Friends of Lesbians and Gays(PFLAG),gays and lesbians are victims of hate crimes seven times as often as straight peers.The question becomes what underlying ideology currently exists in American society to perpetuate this behavior?This paper explores the impact of conservatism and religious ideology to anti-gay prejudice in public schools.The paper presents a model of an intergroup program using prevention of harassment,bullying and rejection to gay members of the student body by attempting a change in attitudes regarding gay students.It also provides recommendations for school administrators and teachers for confronting these challenges in public education.展开更多
Although conservative scholars may face a variety of forms of discrimination in academia and other challenges, as elaborated in the first part of this comment, they may also have a set of unique advantages that may fa...Although conservative scholars may face a variety of forms of discrimination in academia and other challenges, as elaborated in the first part of this comment, they may also have a set of unique advantages that may facilitate more careful theoretical and empirical scientific work. They may be more sensitive to flawed methodologies in some areas of controversy. In such areas, these assets of conservative scholars may be especially important.展开更多
Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a ...Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a discussion of their evolution.Four phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and evaluated.They enabled/facilitated the evolutionary process.Although, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach(i.e., descriptive, diagnosis, testing/evaluation and finally dissemination), much still needs to be done.This leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable manner.Given the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers' intimate involvement in their identification, evaluation and dissemination.Discussion in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders(i.e., farmers, scientists, extension workers, input/output service providers and policymakers).Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research(i.e., CGIAR) system.The paper concludes with a short discussion on the potential role of formal modelling.展开更多
Living fossils are evidence of long-term sustained ecological success.However,whether living fossils have little molecular changes remains poorly known,particularly in plants.Here,we have introduced a novel method tha...Living fossils are evidence of long-term sustained ecological success.However,whether living fossils have little molecular changes remains poorly known,particularly in plants.Here,we have introduced a novel method that integrates phylogenomic,comparative genomic,and ecological niche modeling analyses to investigate the rate of molecular evolution of Eupteleaceae,a Cretaceous relict angiosperm family endemic to East Asia.We assembled a high-quality chromosome-level nuclear genome,and the chloroplast and mitochondrial genomes of a member of Eupteleaceae(Euptelea pleiosperma).Our results show that Eupteleaceae is most basal in Ranunculales,the earliest-diverging order in eudicots,and shares an ancient whole-genome duplication event with the other Ranunculales.We document that Eupteleaceae has the slowest rate of molecular changes in the observed angiosperms.The unusually low rate of molecular evolution of Eupteleaceae across all three independent inherited genomes and genes within each of the three genomes is in association with its conserved genome architecture,ancestral woody habit,and conserved niche requirements.Our findings reveal the evolution and adaptation of living fossil plants through large-scale environmental change and also provide new insights into early eudicot diversification.展开更多
The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ecology.However,the inverse LDG(i-LDG)mec...The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ecology.However,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately explored.Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics.Intriguingly,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely elusive.Here,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within cycads.We then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG pattern.We found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental Asia.Different regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as cradles.Moreover,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the equator.Notably,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern.This study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.展开更多
文摘According to the related data of A-share listed companies in 2009-2013,through extension model based on Basu's surplus - the stock return rate model ,this paper studies that the debt maturity structure influences on accounting conservatism. The empirical study finds that the amount of debt affects significantly the prudence,that is,the greater the amount of the debt contract con- cluded, the stronger role of accounting conservatism is ; Debt maturity have significant relationship with accounting conservatism. For the shorter debt maturity, the enterprise is easier to choose more prudent accounting policy, and when the period is longer, accounting conservatism is relatively weaker.
基金This paper is a periodical result of the Youth Program"Research on Family Narratives in Chinese Literature since Reform and Opening up"(2022EWY004)funded by the Project of Shanghai Planning Office of Philosophy and Social Science.
文摘As one of the representative Chinese writers who was born in the 1970s,Qiao Ye's writing exhibits considerable diversity and varied understandings of literature across genres.In her full-length novels,Qiao Ye is exceptionally innovative and exploratory,and each novel is distinct in subject matter and style.However,her medium-length and short stories tend to be more conservative,characterized by a simple and natural style,imbued with the charm of literary tradition.This artistic stance in writing style is different from other writers and unique to Qiao Ye,which is not only indicative of her vivid artistic individuality but also holds value for further research into creative writing and stylistics.
文摘The culture wars that simmer within any nation may have been escalating recently;but regardless of their national settings or milieus,many of these wars are informed by two opposing paradigms of culture.This paper analyzes two of these leading paradigms,designated here as Regressivism and Progressivism.Other theorists have long chronicled the differing strengths and weaknesses of these paradigms,taking the former as expressing more conservative,traditional,and nationalistic values,and the latter as expressing more liberal,pluralistic,and cosmopolitan values.Going beyond these perennial distinctions,I argue that Progressivism is more benign and beneficial than the former-by meeting basic human needs better and supporting more effective adaptation to changing exigencies.I also argue that Progressivism does not express merely subjective or relativistic preferences and values,but objectively preferable and quantifiable ones,that benefit not only our personal lives more but also our global village and communal lives more.
基金supported by Program for New Century Excellent Talents in University
文摘This paper investigates the factors affecting the conservatism of accounting reports at the market-level and firm-level. At the market-level, law and institutional factors explain conservatism, while at the firm-level contracting is the driver. We predict and observe that while both levels jointly affect conservatism, it is firm-level factors that play a dominant role. The conclusion suggests that it is more effective to improve the quality of accounting reports by motivating the firm's own demand rather than through listing in a developed capital market.
基金financial support received from the National Natural Science Foundation of China (Approval Nos. 71102063, 71572019 and 71232004)the Fundamental Research Funds for Central Universities (Approval Nos. CQDXWL-2013-Z005 and 106112015CDJSK 02XK12)
文摘Based on signaling and gender discrimination theory, we examine whether chief financial officer(CFO) gender matters to bank–firm relationships and the designing of collateral clauses in bank loan contracting, and explore the potential path of influence. Data taken from Chinese listed companies between2009 and 2012 indicate that(1) female-CFO-led firms are less likely to obtain credit loans than male-CFO-led firms;(2) female-CFO-led borrowers are more likely to be required to provide collateral for loans than male-CFO-led borrowers; and(3) banks are more inclined to claim mortgaging collateral when lending to female-CFO-led firms and prefer to guarantee collateral when lending to male-CFO-led firms. Female-CFO-led borrowers seem to be granted more unfavorable loan terms than male-CFO-led borrowers, supporting the hypothesis that female CFOs experience credit discrimination. Further analysis reveals that regional financial development helps to alleviate lending discrimination against female CFOs. Furthermore, female CFOs in SOEs are less likely than their non-SOE counterparts to experience gender discrimination in the credit market.
基金supported by the National Natural Science Foundation of China(Project No.71202170)The Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions(Project No.CIT&TCD201504003)
文摘Using a sample of A-share listed firms in China during the 2003–2012 period,this paper investigates the effect of accounting conservatism on trade credit,taking changes in monetary policy into account.We find that corporations with higher accounting conservatism obtain more trade credit and that accounting conservatism has a greater influence on trade credit under tight monetary policy.Furthermore,the backgrounds of the supplier and customer influence the positive relationship between accounting conservatism and trade credit.This influence is more evident when a company is privately owned and has greater market power,and less evident when the supplier or customer is the controlling shareholder.
基金We warmly thank Irene Konovalova,Danilo Bevk,Paul Williams,Fred-erique Bakker,Maurizio Cornalba,Jakub Straka,and the participants at the ABIM一Alpine Bombus International Meeting for data sharing and/or for the fruitflil discus sions discus sions on Bombus haematurus.The contribution of AC was partly supported through the Project of Ministry of Education,Science and Technological Development of the Republic of Serbia(#III43001).
文摘Species range expansions are crucial for understanding niche formation and the interaction with the environment.Here,we studied the bumblebee Bombus haematurus Kriechbaumer,1870,a species historically distributed from northern Serbia through northern Iran which has very recently started expanding northwestward into Central Europe without human-mediated dispersal(i.e.,it is a natural spread).After updating the global distribution of this species,we investigated if niche shifts took place during this range expansion between newly colonized and historical areas.In addition,we have explored which climatic factors may have favored the natural range expansion of the species.Our results indicated that Bombus haematurus has colonized large territories in 7 European countries outside the historical area in the period from the 1980s to 2018,a natural expansion over an area that equals 20%of the historical distribution.In addition,this bumblebee performs generalism in flower visitation and it occurs in different habitats,although a preference for forested areas clearly emerges.The land-use associated with the species in the colonized areas is similar to the historical distribution,indicating that no major niche shifts occurred during the spread.Furthermore,in recently colonized localities,the range expansion was associated with warming temperatures during the winter and also during both queen overwintering and emergence phases.These findings document a case of natural range expansion due to environmental change rather than due to niche shifts,and specifically they suggest that warmer winters could be linked to the process of natural colonization of new areas.
文摘This study explores the level of unconditional conservatism(UNCC)in accounting after China’s convergence with International Financial Reporting Standards(IFRS).Using the intercept of the Basu(1997)model,an overall reduction is found in UNCC under the Chinese version of IFRS.This study is the first attempt to conduct a comprehensive theoretical comparison between old and new Chinese accounting standards(CAS)in terms of UNCC.Additionally,it is the first study on the impact of convergence with IFRS,not the full adoption of IFRS,on UNCC.Finally,the study covers a relatively more extended period than most previous studies,from 1996 to 2017.
基金supported by funds from the National Natural Science Foundation of China(No.71790603,71672204)
文摘Mergers and acquisitions(M&As)are among the most important investment activities for companies,but they contain great risks.We investigate the role of accounting conservatism in M&A target selection and risk.We find that for risk-averse reasons,firms with high accounting conservatism are likely to acquire profitable targets and avoid loss-making targets.When such firms acquire loss-making targets,the conservatism’s risk-control role reduces M&A risk and increases M&A performance,but only when control of the target is transferred and the acquirer has high long-term debt and low management power.Furthermore,accounting conservatism reduces risk by increasing the maturity match between cash flow and debt.Our results suggest that accounting conservatism plays not only a risk-averse role but also a riskcontrol role,providing new evidence for the usefulness of accounting conservatism in M&A decisions.
基金This study is financially supported by the National Key Research and Development Program of China(No.2018YFA0901800 to H.Yu and L.Ye)Zhejiang Provincial Natural Science Foundation of China(No.LY18B060001 to L.Ye and No.LZ20B060002 to H.Yu)Natural Science Foundation of China(No.21776244 to H.Yu).We are grateful to the constructive suggestions from academician Fen-Er Chen(Department of Chemistry,Fudan University,Shanghai,China)and the support of Discovery Studio software from Fuzhou University platform.
文摘As an important building block for the synthesis of angiotensin-converting enzyme inhibitors,ethyl(R)-2-hy-droxyl-4-phenylbutanoate[(R)-HPBE]has attracted increasing attention.The key to industrial biosynthesis of(R)-HPBE is a biocatalyst that efficiently reduces ethyl 2-oxo-4-phenylbutanoate(OPBE)with high R-enantiose-lectivity.This paper proposed a strategy for identifying key residues involved in enantioselectivity control based on per-residue free energy decomposition and sequence conservatism analysis.Using this strategy,4 noncon-servative sites with high energy contribution to binding of OPBE were chosen as engineering targets,generating variant Mu27 with 99%conversion and 98%(R)ee value at substrate loading of up to 500 mmol/L.MD simu-lations suggested the higher stability and formation probability of Mu27-OPBEproR prereaction state as key rea-sons for the excellent R-enantioselectivity of Mu27 towards OPBE.The success in this study provides a viable approach for rational design of alcohol dehydrogenases with high enantioselectivity towards unnatural substrates.
文摘The political essence of Russian conservatism is to respect the historical tradition and take a development path aligned with Russia's national conditions.Since Putin came to power,Russian conservatism has developed into the mainstream official ideology,becoming the core concept of Russia's current domestic and foreign policies.Russian conservatism is not only the guiding principle of Russia's national foreign policy,but it is also the moral banner of Russia's diplomacy,which reflects its foreign cognition and value system.Under the guidance of conservatism,Russia's foreign policy has distinct offensive features,and Russia has intensified its efforts to counter the liberal international order dominated by the West.After the escalation of the Ukraine crisis,the status of conservatism as Russia's mainstream ideology has been further consolidated,exerting a comprehensive influence on foreign policy.Against the background of extreme sanctions and isolation from the United States and the West,Russia has turned its diplomatic attention to non-Western countries,hoping to build a new international order.
基金funded by the Three New Forestry Project of Jiangsuthe Forestry Technological Innovation and Promotion Program of Jiangsu Province+1 种基金the Postgraduate Research and Practice Innovation Program of Jiangsu Provincethe Doctorate Fellowship Foundation of Nanjing Forestry University,grant number,LYSX[2015]17,LYKJ[2018]29 and KYCX17-0815,respectively。
文摘Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China.
基金Partly supported by the State Major Key Project for Basic Researches
文摘In this paper, an improved splitting method, based on the completely square-conservative explicit difference schemes, is established. Not only can the time-direction precision of this method be higher than that of the traditional splitting methods but also can the physical feature of mutual dependence of the fast and the slow stages that are calculated separately and splittingly be kept as well. Moreover, the method owns an universality, it can be generalized to other square-conservative difference schemes, such as the implicit and complete ones and the explicit and instantaneous ones. Good time benefits can be acquired when it is applied in the numerical simulations of the monthly mean currents of the South China Sea.
基金Coordination for the Improvement of Higher Education Personnel(CAPES)the National Council for Scientific and Technological Development(CNPq)the Minas Gerais State Research Foundation(FAPEMIG)for research funding and scholarships to the authors。
文摘Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human activities.Using a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in Brazil.We recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil characterization.We fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary distinctiveness.We found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water availability.The inferior inselberg habitats harbor higher lineage diversity than expected by chance.Soil strongly predicted evolutionary diversity.We concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems.
基金supported by grants from the National Natural Science Foundation of China (32071493, 31971414 and 31770443)Finance Science and Technology Project of Hainan Province (ZDYF2018219)
文摘Theroleof nicheevolution(niche conservatism or niche divergence)in lineage diversification is a poorly studied area.The Chinese cobra Naja atra(Elapidae)has diverged into three lineages:Lineage E in eastern China,Lineage S in southern China and Vietnam,and Lineage W in western China.However,whether the ecological niche is conserved or divergent among these three lineages is unknown.In the present study,we used ecological niche models in geographical space to study the ecological differences among lineages.We compared the niche overlap in environmental space to test niche conservatism and niche divergence.Our results showed that the three lineages of N.atra shared an ecological niche space between Lineages E and S/W,with the climatic niches of Lineages S and W representing a specialized fraction of the climatic niche of Lineage E.We speculated that the niche divergence between Lineages S and W was a consequence of geographical barriers limitinggeneflow.Ourstudyprovides evidence for lineage diversification associated with both geographical isolation and climatic niche evolution,suggesting that early niche divergence between Lineages S and W,followed by niche conservatism,causes niche divergence among lineages.
文摘According to the advocacy group Parents,Families,and Friends of Lesbians and Gays(PFLAG),gays and lesbians are victims of hate crimes seven times as often as straight peers.The question becomes what underlying ideology currently exists in American society to perpetuate this behavior?This paper explores the impact of conservatism and religious ideology to anti-gay prejudice in public schools.The paper presents a model of an intergroup program using prevention of harassment,bullying and rejection to gay members of the student body by attempting a change in attitudes regarding gay students.It also provides recommendations for school administrators and teachers for confronting these challenges in public education.
文摘Although conservative scholars may face a variety of forms of discrimination in academia and other challenges, as elaborated in the first part of this comment, they may also have a set of unique advantages that may facilitate more careful theoretical and empirical scientific work. They may be more sensitive to flawed methodologies in some areas of controversy. In such areas, these assets of conservative scholars may be especially important.
文摘Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution(i.e., in more heterogeneous and less favourable production environments) areas in low-income countries is followed by a discussion of their evolution.Four phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and evaluated.They enabled/facilitated the evolutionary process.Although, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach(i.e., descriptive, diagnosis, testing/evaluation and finally dissemination), much still needs to be done.This leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable manner.Given the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers' intimate involvement in their identification, evaluation and dissemination.Discussion in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders(i.e., farmers, scientists, extension workers, input/output service providers and policymakers).Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research(i.e., CGIAR) system.The paper concludes with a short discussion on the potential role of formal modelling.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31030000)the National Natural Science Foundation of China(32170210,32170238,31770231,31770233)+2 种基金the Science,Technology,and Innovation Commission of Shenzhen Municipality of China(RCYX20200714114538196)K.C.Wong Education Foundation(GJTD-2020-05)Innovation Program of Chinese Academy of Agricultural Sciences。
文摘Living fossils are evidence of long-term sustained ecological success.However,whether living fossils have little molecular changes remains poorly known,particularly in plants.Here,we have introduced a novel method that integrates phylogenomic,comparative genomic,and ecological niche modeling analyses to investigate the rate of molecular evolution of Eupteleaceae,a Cretaceous relict angiosperm family endemic to East Asia.We assembled a high-quality chromosome-level nuclear genome,and the chloroplast and mitochondrial genomes of a member of Eupteleaceae(Euptelea pleiosperma).Our results show that Eupteleaceae is most basal in Ranunculales,the earliest-diverging order in eudicots,and shares an ancient whole-genome duplication event with the other Ranunculales.We document that Eupteleaceae has the slowest rate of molecular changes in the observed angiosperms.The unusually low rate of molecular evolution of Eupteleaceae across all three independent inherited genomes and genes within each of the three genomes is in association with its conserved genome architecture,ancestral woody habit,and conserved niche requirements.Our findings reveal the evolution and adaptation of living fossil plants through large-scale environmental change and also provide new insights into early eudicot diversification.
基金funded by the National Natural Science Foundation of China(Nos.32270246 and 31900184 to J.L.)the Scientific Foundation of Urban Management Bureau of Shenzhen(Nos.202019 and 202208 to S.Z.)+1 种基金the Youth Innovation Promotion Association CAS,China(Grant No.:2023410)the Yunnan Fundamental Research Projects(Grant Nos.:202001AT070072 and 2019FD057 to J.L.)。
文摘The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ecology.However,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately explored.Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics.Intriguingly,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely elusive.Here,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within cycads.We then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG pattern.We found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental Asia.Different regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as cradles.Moreover,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the equator.Notably,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern.This study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.