[ Objective ] The insecticidal and antibacterial bioactivity of Wikstroemia chamaedaphne Meissn were screened and bioactive substances in it were separated and purified. [ Method] The Wikstroemia chamaedaphne Meissn w...[ Objective ] The insecticidal and antibacterial bioactivity of Wikstroemia chamaedaphne Meissn were screened and bioactive substances in it were separated and purified. [ Method] The Wikstroemia chamaedaphne Meissn was conducted ultrasonic extraction in petroleum ether, ethyl acetate and methanol. The insecticidal activity of Wikstroemia chamaedaphne Meissn to Mythimna separata walker and aphid were determined. The antibacterial activity of Wikstroemia chamaedaphne Meissn to Fusarium graminearu, Glomerella cingulata, F. oxysporium f. sp niveum, Alternaria solani and Fusarium oxysporium were also determined. The bioactivity-guided methods such as opencolumn chromatography and Pre-HPLC method were used to separate active components in petroleum ether extract from Wikstroemia chamaedaphne Meissn. [ Result] When the concentration was 500 mg/L, 3 kinds of extracts from Wikstroemia chamaedaphne Meissn didn' t show obvious antibacterial bioactivity to 5 kinds of test samples. When the concentration was 5%, petroleum ether extract show certain topical toxicity to aphids. The ethyl acetate extract showed certain antifeedant activity to 3^rd instar Larvae of Mythimna separata Walker. The fraction F4 of petroleum ether extract possessed highest topical toxicity to aphids and the lethality was 60.00%. [ Conclusion] Wikstroemia chamaedaphne Meissn contained many insecticidal constituents whose active parts and mechanism were needed further researches.展开更多
The species composition of regional plant assemblages can in large part be explained by a long history of biogeographical and evolutionary events. Traditional attempts of floristic studies typically focus on the analy...The species composition of regional plant assemblages can in large part be explained by a long history of biogeographical and evolutionary events. Traditional attempts of floristic studies typically focus on the analyses of taxonomic composition, often ignoring the rich context that evolutionary history can provide. In 2014, Swenson and Umafia introduced the term 'phylofloristics' to define a phylogenetically enabled analysis of the species composition of regional floras. Integrating phylogenetic information into tradi- tional floristic analysis can provide a promising way to explore the ecological, biogeographic, and evolutionary processes that drive plant assemblies at multiple spatial scales. In this review, we sum- marize the current progress on the phylogenetic structure, spatial phylogenetic pattern, origin and diversification, phylogenetic regionalization of fioristic assemblages, and application of phylogenetic information in biodiversity conservation. These summaries highlight the importance of incorporating phylogenetic information to improve our understanding of floristic assembly from an evolutionary perspective. The review ends with a brief outlook on future challenges for phylofloristic studies, including generating a highly resolved species-level phylogenetic tree, compiling detailed and refined information regarding the geographic distribution of all plant life, extracting trait information from publications and herbarium specimens, and developing technological and methodological approaches for big data analysis.展开更多
Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positiv...Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positive associations between alpine cushion plants and rhizospheric microbes have been limited to the vegetation growing season.Here,we asked whether the positive effects that alpine cushion plants confer on rhizospheric microbe communities vary with seasons.We assessed seasonal variations in the bacterial diversity and composition in rhizosphere of two alpine cushion plants and surrounding bare ground by employing a high throughput sequencing method targeting the V3 region of bacterial 16 S rRNA genes.Soil properties of the rhizosphere and the bare ground were also examined.We found that cushion rhizospheres harbored significantly more C,N,S,ammonia nitrogen,and soil moisture than the bare ground.Soil properties in cushion rhizospheres were not notably different,except for soil pH.Bacterial diversities within the same microhabitats did not vary significantly with seasons.We concluded that alpine cushion plants had positive effects on the rhizospheric bacterial communities,even though the strength of the effect varied in different cushion species.Cushion species and the soil sulfur content were probably the major factors driving the spatial distribution and structure of soil bacterial communities in the alpine communities dominated by cushion plants.展开更多
Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological conditi...Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological condition provide more services than those in poor ecological condition.This is because rangelands in good condition support a more diverse mixture of vegetation with many benefits,such as forage for livestock and medicinal plants.Nearly one-quarter of Tunisia,covering about 5.5 million hectares,are rangelands,of which 87% are located in the arid and desert areas(45% and 42%,respectively).Here,we provide a brief review of the floristic richness of desert rangelands of Tunisia.Approximately 135 species are specific to desert rangelands.The predominant families are Asteraceae,Poaceae,Brassicaceae,Chenopodiaceae,and Fabaceae.These represent approximately 50% of Tunisian desert flora.展开更多
A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN (duplex-specific nuclease) normalization method combined with the SMART (Switching Mechanism At 5' end ...A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN (duplex-specific nuclease) normalization method combined with the SMART (Switching Mechanism At 5' end of the RNA Transcript) technique. The titer of the original cDNA library was about 1.5 × 10^6 cfu·mL^-1 and the average insertion size was about 1 kb with a high recombination rate (97%). The 5011 high-quality expressed sequence tags (ESTs) were obtained from 5393 randomly picked cDNA clones. Clustering and assembly of ESTs resulted in 2984 unique sequences, consisting of 618 contigs and 2366 singlets. EST sequence annotation revealed that 2333 and 1901 unigenes were functionally anno- tated in the NCBI non-redundant database and Swiss-Prot protein database, respectively. Functional analysis demonstrated that 1495 (50.1%) unigenes were associated with 4082 Gene Ontology (GO) terms. A total of 847 unigenes were grouped into 22 Cluster of Orthologous Groups (COG) functional categories. Based on the EST dataset, 22 ESTs that encoded putative receptor-like protein kinase (RLK) genes were screened. Furthermore, a total of 94 simple sequence repeats (SSRs) were discovered, of which 20 loci were successfully amplified in C debaoensis. This study is the first EST analysis for the coralloid roots of C debaoensis and provides a valuable genomic resource for novel gene discovery, gene expression and comparative genomics, conservation and management studies as well as applications in C debaoensis and related cycad species.展开更多
Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have don...Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have done little work regarding their medicinal properties. This paper aimed to present the results of ethnobotanical, pharmacological and active compounds research on Veracruz medicinal orchids. The ethnobotanical information was obtained by consulting the Atlas of the Mexican Traditional Medicine Plants, Veracruz Medicinal Flora Database (CITRO-UV project) and through field work in the Nahuatl community of Cuautlajapa, Veracruz. To obtain pharmacological and active compounds information of registered species, a search was carded out through MEDLINE (USA National Library of Medicine Journal Citation database). Twelve medicinal orchids were recorded for Veracruz, i.e., Epidendrum chlorocorymbos Schltr., Habenaria floribunda Lindl., Isochillus latibracteatus A. Rich. & Galeotti, lsochillus major Schltdl. & Cham., Mormodes maculata var. unicolor (Hook.) L. O. Williams, Oestlundia luteorosea (A. Rich. & Galeotti) W. E. Higgins, Oncidium ascendens Lindl., Scaphyglottis fasciculata Hook., Sobralia macrantha Lindl., Spiranthes eriophora (Rob. & Greenm.), Stanhopea oculata (G. Lodd.) Lindl. and Vanilla planifolia Andrews. Only two species have been investigated in terms of their pharmacology and active compounds. Also, information for another five species closely related to already identified ones was obtained. Given the relative poverty of current information on the topic, this paper demonstrates the need to further study the ethnobotanical, pharmacological and chemical aspects of the region's medicinal orchids.展开更多
The cytotoxicity of abamectin to the Gill Cell Line of Flounder (FG cell line) was examined in this study. It was found that the exposure of FG cells to abamectin caused the decreases of both cell growth rate and an...The cytotoxicity of abamectin to the Gill Cell Line of Flounder (FG cell line) was examined in this study. It was found that the exposure of FG cells to abamectin caused the decreases of both cell growth rate and antioxidant enzyme activities, and the increase of intracellular 02 content. It was proposed that the reduction of antioxidant enzyme activities in FG cells caused the accumulation of 02 content in FG cells, leading to the change of cell morphology and even the death of cells. The results showed that FG cell line is suitable for the evaluation of the acute toxicity of abamectin.展开更多
Europe's mountains cover nearly half of the continent's area and are home to one fifth of the European population. Mountain areas are hotspots of biodiversity and agriculture has played a multifunctional role in def...Europe's mountains cover nearly half of the continent's area and are home to one fifth of the European population. Mountain areas are hotspots of biodiversity and agriculture has played a multifunctional role in defining and sustaining mountain biodiversity. Ongoing trends of agricultural decline are having negative impacts on mountain biodiversity. This paper presents results from an interdisciplinary European research project, BioScene, which investigated the relationship between agriculture and biodiversity in six mountain study areas across Europe to provide recommendations for reconciling biodiversity conservation with social and economic activities through an integrated rural development strategy. BioScene used scenario analysis and stakeholder participation as tools for structuring the analysis of alternative mountain futures. Three main BioScene scenarios were evaluated: Business as Usual (BAIT), Agricultural Liberalisation (Lib), Managed Change for Biodiversity (MCB). BioScene brought together ecologists, economists, sociologists and rural geogra- phers, to carry out interdisciplinary analysis of the scenarios: identifying key drivers of change, assessing the biodiversity consequences and evaluating costeffectiveness. BioScene used a sustainability assessment to integrate the research outputs across natural and social science disciplines to assess the broader sustainability of the scenarios in terms of biodiversity, natural resources, rural development, social development, economic development and institutional capacity. The sustainability assessment showed that the MCB scenario was potentially the most sustainable of the three BioScene scenarios. Through the reconciliation of potentially conflicting objectives, such as conservation, economic development and human livelihoods, and with a strong participatory planning approach, the MCB scenario could represent an alternative approach to BaU for sustainable rural development in Europe's mountains. BioScene confirms the necessity for natural and social scientists to work together to seek solutions to environmental problems. Interdisciplinary research can assist with the definition of integrated strategies with the potential to reconcile the ecological, social and economic parameters that determine a sustainable future for European mountain areas.展开更多
The region of Tlemcen is located in the northwestern part of Algeria. Its arid climate leads to the degradation of vegetation in open formation, where can be found the doum, the diss and broom. Other aromatic species ...The region of Tlemcen is located in the northwestern part of Algeria. Its arid climate leads to the degradation of vegetation in open formation, where can be found the doum, the diss and broom. Other aromatic species such as rosemary, thyme, lavender and horehound are considered as well. The four previous aromatic species belong to the family Labiatae for their morphological and botanical characters. The authors propose to design an approach to identify the diversity of malacofauna found on these different Lamiaceae. These are certainly a nutritional source for this malacological fauna. So, a survey was performed in various stations. The malacological richness is estimated to be 19 for thyme, 18 for rosemary, 16 for lavender, and finally 7 for horehound. It includes four families, namely Milacidae, Sphincterochilidae, Helicidae and Subulinidae. Milacidae are present only in horehound and lavender stations. On the other hand, the Sphincterochilidae, namely Sphincterochila candidissima, is absent on horehound. Rumina decollata is the only species in the family Subulinidae. As for the family Helicidae, it is the richest and includes two specific subfamilies: Helicinae and Helicellinae. The first subfamily consists of 11 species of thyme, 10 species of rosemary and lavender. The second subfamily includes 6 species of thyme and rosemary and 3 of lavender, respectively. In addition, the author tries to look for the malacological species specific to each of these plants and those who are common to them as well. Finally, the vertical distribution of gastropods is given.展开更多
The exciting outcomes of national regional trials have led to production and industrialization of China oilseed rape to a larger extent. To understand current trends of yield and quality traits of new varieties, data ...The exciting outcomes of national regional trials have led to production and industrialization of China oilseed rape to a larger extent. To understand current trends of yield and quality traits of new varieties, data of national winter oilseed rape trials from 2001 to 2015 in 4 districts (upper, middle, lower Yangtze River and Huang-Huai River) was comprehensively analyzed. Results showed that average yield of new varieties of winter oilseed rape increased during the study period. In 2013, average yield of each district reached its highest level. Number of pod per plant reached its peak in 2011 and then declined rapidly in the next 4 years. Average number of seeds per pod did not signif-cantly changed in any districts. Moreover, 1,000 seeds weight increased most obviously in Huang-Huai River district. After 2007, new oilseed rape varieties encountered the dou-ble-low quality (i.e., low erucic acid and low glucosinolate). In addition, oil content of new oilseed rape varieties increased over 15 years period and average oil content of all tested varieties during 2006-2015 was 42.96%, which was 2.38% higher than in 2005. Future breeding goals should be set to further improve yield, oil content, oil quality (such as high oleic acid and low saturated fatty acids), achieve full mechanization of oilseed rape pro-duction process and develop ideotypes.展开更多
This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of...This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of a wetland. Defining the marsh and wetland plants is the basis for understanding the wetland and its biodiversity. The comprehensive multiple factorial classification principles and the multiple developmental models of the wetland are two innovative feats achieved by Chinese scientists, and their application has further promoted ecological research. The CAS Wetland Research Center has made historic contributions to the study of the wetland and its biodiversity in China. Also, the paper discusses several important tasks of wetland and biodiversity research.展开更多
The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was dev...The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was developed to simplify detection of enzyme activity of amylase, protease and lipase on starch agar, dry whole milk agar, and trihutyrin agar, respectively. The subjects of the study were 24 senior undergraduates who studied in the Program of General Science, Faculty of Science, Srinakharinwirot University, Bangkok, in three semesters during 2007 - 2008. The basic concepts of enzymes, e.g., substrate specificity, how to detect enzymes and optimal enzyme conditions, were taught before the practical. The first enzyme, protease, was used in the second semester of 2007, and then changed to be lipase and protease in the first and second semesters of 2008, respectively. Ten open-ended questions were used to assess students in all semesters. In agreement with the constructivist learning model, it was demonstrated that students had learning retention and applied their prior knowledge to other enzyme experiments.展开更多
The pioneer technical policy carried out by Federal State Institution "Novorossiysk Maritime Port Administration" in mutual cooperation with the Southern Scientific Centre of Russian Academy of Sciences on control a...The pioneer technical policy carried out by Federal State Institution "Novorossiysk Maritime Port Administration" in mutual cooperation with the Southern Scientific Centre of Russian Academy of Sciences on control and management of ballast waters and ecosystem monitoring of marine environment in areas of ballast water discharge provides the task of complex approach for minimization of risk of introduction of biologically negative invaders by marine transport and preservation of biodiversity of the Black Sea.展开更多
Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the a...Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the authors propose that science-based botanical gardens (which differ from common public gardens), should be founded on plant diversity inventory and ex-situ conservation of wild plant species. Efforts should be directed to rarer species from biodiversity-rich areas and biodiversity hotspots, utilizing cutting-edge technologies to effectively preserve germplasm in living collections. Science-based botanical garden management should be directed by sound scientific evaluation of plant resources and guaranteed by innovative operational mechanisms. Science-based botanical gardens should also emphasize the establishment of identifiable and specialized living collections, research platforms and recruitment of qualified experts. In addition to curating living specimens, science-based botanical gardens should pursue research and development of new plant varieties or patents based on their plant collections, thus providing continual support to bio-industry.展开更多
As in any field of research, the study of sexual selection is subject to ongoing debate over definitions and interpreta- tions of the fundamental concepts involved. These arguments generally promote progress, as they ...As in any field of research, the study of sexual selection is subject to ongoing debate over definitions and interpreta- tions of the fundamental concepts involved. These arguments generally promote progress, as they highlight areas where current explanations are incomplete. Here we briefly review two ongoing discussions in the sexual selection literature. First, the definition of sexual selection has received renewed interest in light of increasing research effort into when and how it operates in females. Second, how best to measure sexual selection is an ongoing subject of debate; in practice, recognition that the appropriate measures depend on the focus of the specific study, and that multiple measures should be employed wherever possible, seems to provide the most informative approach. The wide scope of recent empirical work in these and related areas, with the application of new techniques and approaches, reflects that the field of sexual selection is being constantly expanded and enriched展开更多
Geobiology is a new discipline on the crossing interface between earth science and life science, and aims to understand the in- teraction and co-evolution between organisms and environments. On the basis of the latest...Geobiology is a new discipline on the crossing interface between earth science and life science, and aims to understand the in- teraction and co-evolution between organisms and environments. On the basis of the latest international achievements, the new data presented in the Beijing geobiology forum sponsored by Chinese Academy of Sciences in 2013, and the papers in this special issue, here we present an overview of the progress and perspectives on three important frontiers, including geobiology of the critical periods in Earth history, geomicrobes and their responses and feedbacks to global environmental changes, and geobiology in extreme environments. Knowledge is greatly improved about the close relationship of some significant biotic events such as origin, radiation, extinction, and recovery of organisms with the deep Earth processes and the resultant envi- ronmental processes among oceans, land, and atmosphere in the critical periods, although the specific dynamics of the co-evolution between ancient life and paleoenvironments is still largely unknown. A variety of geomicrobial functional groups were found to respond sensitively to paleoenvironmental changes, which enable the establishment of proxies for paleoenvi- ronmental reconstruction, and to play active roles on the Earth environmental changes via elemental biogeochemical cycles and mineral bio-transforrnations, but to be deciphered are the mechanisms of these functional groups that change paleoenvi- ronmental conditions. Microbes of potential geobiology significance were found and isolated from some extreme environments with their biological properties partly understood, but little is known about their geobiological functions to change Earth envi- ronments. The biotic processes to alter or modify the environments are thus proposed to be the very issue geobiology aims to decipher in the future. Geobiology will greatly extend the temporal and spatial scope of biotic research on Earth and beyond. It has great potential of application in the domains of resource exploration and global change. To achieve these aims needs coor- dinative multidisciplinary studies concerning geomicrobiology and related themes, database and modeling of biogeochemical cycles, typical geological environments, and coupling of biological, physical, and chemical processes.展开更多
Topological materials, hosting topological nontrivial electronic band, have attracted widespread attentions. As an application of topology in physics, the discovery and study of topological materials not only enrich t...Topological materials, hosting topological nontrivial electronic band, have attracted widespread attentions. As an application of topology in physics, the discovery and study of topological materials not only enrich the existing theoretical framework of physics, but also provide fertile ground for investigations on low energy excitations, such as Weyl fermions and Majorana fermions, which have not been observed yet as fundamental particles. These quasiparticles with exotic physical properties make topological materials the cutting edge of scientific research and a new favorite of high tech. As a typical example, Majorana fermions, predicted to exist in the edge state of topological superconductors, are proposed to implement topological error-tolerant quantum computers. Thus, the detection of topological superconductivity has become a frontier in condensed matter physics and materials science. Here, we review a way to detect topological superconductivity triggered by the hard point contact: tip-induced superconductivity(TISC) and tip-enhanced superconductivity(TESC). The TISC refers to the superconductivity induced by a non-superconducting tip at the point contact on non-superconducting materials. We take the elaboration of the chief experimental achievement of TISC in topological Dirac semimetal Cd_3As_2 and Weyl semimetal Ta As as key components of this article for detecting topological superconductivity. Moreover, we also briefly introduce the main results of another exotic effect, TESC, in superconducting Au_2Pb and Sr_2RuO_4 single crystals, which are respectively proposed as the candidates of helical topological superconductor and chiral topological superconductor. Related results and the potential mechanism are conducive to improving the comprehension of how to induce and enhance the topological superconductivity.展开更多
Predictive simulation of engine combustion is key to understanding the underlying complicated physicochemical processes,improving engine performance,and reducing pollutant emissions.Critical issues as turbulence model...Predictive simulation of engine combustion is key to understanding the underlying complicated physicochemical processes,improving engine performance,and reducing pollutant emissions.Critical issues as turbulence modeling,turbulence-chemistry interaction,and accommodation of detailed chemical kinetics in complex flows remain challenging and essential for highfidelity combustion simulation.This paper reviews the current status of the state-of-the-art large eddy simulation(LES)/probability density function(PDF)/detailed chemistry approach that can address the three challenging modelling issues.PDF as a subgrid model for LES is formulated and the hybrid mesh-particle method for LES/PDF simulations is described.Then the development need in micro-mixing models for the PDF simulations of turbulent premixed combustion is identified.Finally the different acceleration methods for detailed chemistry are reviewed and a combined strategy is proposed for further development.展开更多
基金Supported by School Project of Yan’an University (YD2005-042)~~
文摘[ Objective ] The insecticidal and antibacterial bioactivity of Wikstroemia chamaedaphne Meissn were screened and bioactive substances in it were separated and purified. [ Method] The Wikstroemia chamaedaphne Meissn was conducted ultrasonic extraction in petroleum ether, ethyl acetate and methanol. The insecticidal activity of Wikstroemia chamaedaphne Meissn to Mythimna separata walker and aphid were determined. The antibacterial activity of Wikstroemia chamaedaphne Meissn to Fusarium graminearu, Glomerella cingulata, F. oxysporium f. sp niveum, Alternaria solani and Fusarium oxysporium were also determined. The bioactivity-guided methods such as opencolumn chromatography and Pre-HPLC method were used to separate active components in petroleum ether extract from Wikstroemia chamaedaphne Meissn. [ Result] When the concentration was 500 mg/L, 3 kinds of extracts from Wikstroemia chamaedaphne Meissn didn' t show obvious antibacterial bioactivity to 5 kinds of test samples. When the concentration was 5%, petroleum ether extract show certain topical toxicity to aphids. The ethyl acetate extract showed certain antifeedant activity to 3^rd instar Larvae of Mythimna separata Walker. The fraction F4 of petroleum ether extract possessed highest topical toxicity to aphids and the lethality was 60.00%. [ Conclusion] Wikstroemia chamaedaphne Meissn contained many insecticidal constituents whose active parts and mechanism were needed further researches.
基金supported by the National Natural Science Foundation of China (grant no. 31570212, 31770228, 31370243)the Talent Project of Yunnan (grant no. 2015HB092)
文摘The species composition of regional plant assemblages can in large part be explained by a long history of biogeographical and evolutionary events. Traditional attempts of floristic studies typically focus on the analyses of taxonomic composition, often ignoring the rich context that evolutionary history can provide. In 2014, Swenson and Umafia introduced the term 'phylofloristics' to define a phylogenetically enabled analysis of the species composition of regional floras. Integrating phylogenetic information into tradi- tional floristic analysis can provide a promising way to explore the ecological, biogeographic, and evolutionary processes that drive plant assemblies at multiple spatial scales. In this review, we sum- marize the current progress on the phylogenetic structure, spatial phylogenetic pattern, origin and diversification, phylogenetic regionalization of fioristic assemblages, and application of phylogenetic information in biodiversity conservation. These summaries highlight the importance of incorporating phylogenetic information to improve our understanding of floristic assembly from an evolutionary perspective. The review ends with a brief outlook on future challenges for phylofloristic studies, including generating a highly resolved species-level phylogenetic tree, compiling detailed and refined information regarding the geographic distribution of all plant life, extracting trait information from publications and herbarium specimens, and developing technological and methodological approaches for big data analysis.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFC0505200,to Hang Sun)the Major Program of National Natural Science Foundation of China(Grant No.31590823,to Hang Sun)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA20050203,to Hang Sun)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB15020302,to Jianqiang Su)the Yunnan Applied Basic Research Project(Grant No.2018FA015,to Yang Yang)
文摘Positive associations between alpine cushion plants and other species have been extensively studied.However,almost all studies have focused on the associations between macrofauna.Studies that have investigated positive associations between alpine cushion plants and rhizospheric microbes have been limited to the vegetation growing season.Here,we asked whether the positive effects that alpine cushion plants confer on rhizospheric microbe communities vary with seasons.We assessed seasonal variations in the bacterial diversity and composition in rhizosphere of two alpine cushion plants and surrounding bare ground by employing a high throughput sequencing method targeting the V3 region of bacterial 16 S rRNA genes.Soil properties of the rhizosphere and the bare ground were also examined.We found that cushion rhizospheres harbored significantly more C,N,S,ammonia nitrogen,and soil moisture than the bare ground.Soil properties in cushion rhizospheres were not notably different,except for soil pH.Bacterial diversities within the same microhabitats did not vary significantly with seasons.We concluded that alpine cushion plants had positive effects on the rhizospheric bacterial communities,even though the strength of the effect varied in different cushion species.Cushion species and the soil sulfur content were probably the major factors driving the spatial distribution and structure of soil bacterial communities in the alpine communities dominated by cushion plants.
基金supported by the International Center for Agricultural Research in the Dry Areas(ICARDA)the Arid Regions Institute(IRA e Medenine,Tunisia)and the CGIAR Research Program on Livestock(CRP Livestock)
文摘Plants are important components of any rangeland.However,the importance of desert rangeland plant diversity has often been underestimated.It has been argued that desert rangelands of Tunisia in good ecological condition provide more services than those in poor ecological condition.This is because rangelands in good condition support a more diverse mixture of vegetation with many benefits,such as forage for livestock and medicinal plants.Nearly one-quarter of Tunisia,covering about 5.5 million hectares,are rangelands,of which 87% are located in the arid and desert areas(45% and 42%,respectively).Here,we provide a brief review of the floristic richness of desert rangelands of Tunisia.Approximately 135 species are specific to desert rangelands.The predominant families are Asteraceae,Poaceae,Brassicaceae,Chenopodiaceae,and Fabaceae.These represent approximately 50% of Tunisian desert flora.
基金supported by the Grant(201522)from Shenzhen Urban Management
文摘A normalized full-length cDNA library was constructed from the coralloid roots of Cycas debaoensis by the DSN (duplex-specific nuclease) normalization method combined with the SMART (Switching Mechanism At 5' end of the RNA Transcript) technique. The titer of the original cDNA library was about 1.5 × 10^6 cfu·mL^-1 and the average insertion size was about 1 kb with a high recombination rate (97%). The 5011 high-quality expressed sequence tags (ESTs) were obtained from 5393 randomly picked cDNA clones. Clustering and assembly of ESTs resulted in 2984 unique sequences, consisting of 618 contigs and 2366 singlets. EST sequence annotation revealed that 2333 and 1901 unigenes were functionally anno- tated in the NCBI non-redundant database and Swiss-Prot protein database, respectively. Functional analysis demonstrated that 1495 (50.1%) unigenes were associated with 4082 Gene Ontology (GO) terms. A total of 847 unigenes were grouped into 22 Cluster of Orthologous Groups (COG) functional categories. Based on the EST dataset, 22 ESTs that encoded putative receptor-like protein kinase (RLK) genes were screened. Furthermore, a total of 94 simple sequence repeats (SSRs) were discovered, of which 20 loci were successfully amplified in C debaoensis. This study is the first EST analysis for the coralloid roots of C debaoensis and provides a valuable genomic resource for novel gene discovery, gene expression and comparative genomics, conservation and management studies as well as applications in C debaoensis and related cycad species.
文摘Orchidaceae is a large family of 1,260 species in Mexico, of which 433 grow in the state of Veracruz, Mexico. Although economically important in horticulture because of the beauty of their flowers, researches have done little work regarding their medicinal properties. This paper aimed to present the results of ethnobotanical, pharmacological and active compounds research on Veracruz medicinal orchids. The ethnobotanical information was obtained by consulting the Atlas of the Mexican Traditional Medicine Plants, Veracruz Medicinal Flora Database (CITRO-UV project) and through field work in the Nahuatl community of Cuautlajapa, Veracruz. To obtain pharmacological and active compounds information of registered species, a search was carded out through MEDLINE (USA National Library of Medicine Journal Citation database). Twelve medicinal orchids were recorded for Veracruz, i.e., Epidendrum chlorocorymbos Schltr., Habenaria floribunda Lindl., Isochillus latibracteatus A. Rich. & Galeotti, lsochillus major Schltdl. & Cham., Mormodes maculata var. unicolor (Hook.) L. O. Williams, Oestlundia luteorosea (A. Rich. & Galeotti) W. E. Higgins, Oncidium ascendens Lindl., Scaphyglottis fasciculata Hook., Sobralia macrantha Lindl., Spiranthes eriophora (Rob. & Greenm.), Stanhopea oculata (G. Lodd.) Lindl. and Vanilla planifolia Andrews. Only two species have been investigated in terms of their pharmacology and active compounds. Also, information for another five species closely related to already identified ones was obtained. Given the relative poverty of current information on the topic, this paper demonstrates the need to further study the ethnobotanical, pharmacological and chemical aspects of the region's medicinal orchids.
文摘The cytotoxicity of abamectin to the Gill Cell Line of Flounder (FG cell line) was examined in this study. It was found that the exposure of FG cells to abamectin caused the decreases of both cell growth rate and antioxidant enzyme activities, and the increase of intracellular 02 content. It was proposed that the reduction of antioxidant enzyme activities in FG cells caused the accumulation of 02 content in FG cells, leading to the change of cell morphology and even the death of cells. The results showed that FG cell line is suitable for the evaluation of the acute toxicity of abamectin.
文摘Europe's mountains cover nearly half of the continent's area and are home to one fifth of the European population. Mountain areas are hotspots of biodiversity and agriculture has played a multifunctional role in defining and sustaining mountain biodiversity. Ongoing trends of agricultural decline are having negative impacts on mountain biodiversity. This paper presents results from an interdisciplinary European research project, BioScene, which investigated the relationship between agriculture and biodiversity in six mountain study areas across Europe to provide recommendations for reconciling biodiversity conservation with social and economic activities through an integrated rural development strategy. BioScene used scenario analysis and stakeholder participation as tools for structuring the analysis of alternative mountain futures. Three main BioScene scenarios were evaluated: Business as Usual (BAIT), Agricultural Liberalisation (Lib), Managed Change for Biodiversity (MCB). BioScene brought together ecologists, economists, sociologists and rural geogra- phers, to carry out interdisciplinary analysis of the scenarios: identifying key drivers of change, assessing the biodiversity consequences and evaluating costeffectiveness. BioScene used a sustainability assessment to integrate the research outputs across natural and social science disciplines to assess the broader sustainability of the scenarios in terms of biodiversity, natural resources, rural development, social development, economic development and institutional capacity. The sustainability assessment showed that the MCB scenario was potentially the most sustainable of the three BioScene scenarios. Through the reconciliation of potentially conflicting objectives, such as conservation, economic development and human livelihoods, and with a strong participatory planning approach, the MCB scenario could represent an alternative approach to BaU for sustainable rural development in Europe's mountains. BioScene confirms the necessity for natural and social scientists to work together to seek solutions to environmental problems. Interdisciplinary research can assist with the definition of integrated strategies with the potential to reconcile the ecological, social and economic parameters that determine a sustainable future for European mountain areas.
文摘The region of Tlemcen is located in the northwestern part of Algeria. Its arid climate leads to the degradation of vegetation in open formation, where can be found the doum, the diss and broom. Other aromatic species such as rosemary, thyme, lavender and horehound are considered as well. The four previous aromatic species belong to the family Labiatae for their morphological and botanical characters. The authors propose to design an approach to identify the diversity of malacofauna found on these different Lamiaceae. These are certainly a nutritional source for this malacological fauna. So, a survey was performed in various stations. The malacological richness is estimated to be 19 for thyme, 18 for rosemary, 16 for lavender, and finally 7 for horehound. It includes four families, namely Milacidae, Sphincterochilidae, Helicidae and Subulinidae. Milacidae are present only in horehound and lavender stations. On the other hand, the Sphincterochilidae, namely Sphincterochila candidissima, is absent on horehound. Rumina decollata is the only species in the family Subulinidae. As for the family Helicidae, it is the richest and includes two specific subfamilies: Helicinae and Helicellinae. The first subfamily consists of 11 species of thyme, 10 species of rosemary and lavender. The second subfamily includes 6 species of thyme and rosemary and 3 of lavender, respectively. In addition, the author tries to look for the malacological species specific to each of these plants and those who are common to them as well. Finally, the vertical distribution of gastropods is given.
基金supported by National key R&D program(2017 YFD0102000)
文摘The exciting outcomes of national regional trials have led to production and industrialization of China oilseed rape to a larger extent. To understand current trends of yield and quality traits of new varieties, data of national winter oilseed rape trials from 2001 to 2015 in 4 districts (upper, middle, lower Yangtze River and Huang-Huai River) was comprehensively analyzed. Results showed that average yield of new varieties of winter oilseed rape increased during the study period. In 2013, average yield of each district reached its highest level. Number of pod per plant reached its peak in 2011 and then declined rapidly in the next 4 years. Average number of seeds per pod did not signif-cantly changed in any districts. Moreover, 1,000 seeds weight increased most obviously in Huang-Huai River district. After 2007, new oilseed rape varieties encountered the dou-ble-low quality (i.e., low erucic acid and low glucosinolate). In addition, oil content of new oilseed rape varieties increased over 15 years period and average oil content of all tested varieties during 2006-2015 was 42.96%, which was 2.38% higher than in 2005. Future breeding goals should be set to further improve yield, oil content, oil quality (such as high oleic acid and low saturated fatty acids), achieve full mechanization of oilseed rape pro-duction process and develop ideotypes.
文摘This paper briefly summarizes the history of wetland research, the evolvement of wetland science, and their impacts on the understanding of wetland biodiversity in China. A marsh is the key type and basic component of a wetland. Defining the marsh and wetland plants is the basis for understanding the wetland and its biodiversity. The comprehensive multiple factorial classification principles and the multiple developmental models of the wetland are two innovative feats achieved by Chinese scientists, and their application has further promoted ecological research. The CAS Wetland Research Center has made historic contributions to the study of the wetland and its biodiversity in China. Also, the paper discusses several important tasks of wetland and biodiversity research.
文摘The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was developed to simplify detection of enzyme activity of amylase, protease and lipase on starch agar, dry whole milk agar, and trihutyrin agar, respectively. The subjects of the study were 24 senior undergraduates who studied in the Program of General Science, Faculty of Science, Srinakharinwirot University, Bangkok, in three semesters during 2007 - 2008. The basic concepts of enzymes, e.g., substrate specificity, how to detect enzymes and optimal enzyme conditions, were taught before the practical. The first enzyme, protease, was used in the second semester of 2007, and then changed to be lipase and protease in the first and second semesters of 2008, respectively. Ten open-ended questions were used to assess students in all semesters. In agreement with the constructivist learning model, it was demonstrated that students had learning retention and applied their prior knowledge to other enzyme experiments.
文摘The pioneer technical policy carried out by Federal State Institution "Novorossiysk Maritime Port Administration" in mutual cooperation with the Southern Scientific Centre of Russian Academy of Sciences on control and management of ballast waters and ecosystem monitoring of marine environment in areas of ballast water discharge provides the task of complex approach for minimization of risk of introduction of biologically negative invaders by marine transport and preservation of biodiversity of the Black Sea.
文摘Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the authors propose that science-based botanical gardens (which differ from common public gardens), should be founded on plant diversity inventory and ex-situ conservation of wild plant species. Efforts should be directed to rarer species from biodiversity-rich areas and biodiversity hotspots, utilizing cutting-edge technologies to effectively preserve germplasm in living collections. Science-based botanical garden management should be directed by sound scientific evaluation of plant resources and guaranteed by innovative operational mechanisms. Science-based botanical gardens should also emphasize the establishment of identifiable and specialized living collections, research platforms and recruitment of qualified experts. In addition to curating living specimens, science-based botanical gardens should pursue research and development of new plant varieties or patents based on their plant collections, thus providing continual support to bio-industry.
文摘As in any field of research, the study of sexual selection is subject to ongoing debate over definitions and interpreta- tions of the fundamental concepts involved. These arguments generally promote progress, as they highlight areas where current explanations are incomplete. Here we briefly review two ongoing discussions in the sexual selection literature. First, the definition of sexual selection has received renewed interest in light of increasing research effort into when and how it operates in females. Second, how best to measure sexual selection is an ongoing subject of debate; in practice, recognition that the appropriate measures depend on the focus of the specific study, and that multiple measures should be employed wherever possible, seems to provide the most informative approach. The wide scope of recent empirical work in these and related areas, with the application of new techniques and approaches, reflects that the field of sexual selection is being constantly expanded and enriched
基金supported by the project on Strategy Development of Geobiology and Astrobiology from Chinese Academy of Sciences, National Basic Research Program of China (Grant No. 2011CB808800)National Natural Science Foundation of China (Grant No. 41330103)the "111" Program from Ministry of Education of China (Grant No. B08030)
文摘Geobiology is a new discipline on the crossing interface between earth science and life science, and aims to understand the in- teraction and co-evolution between organisms and environments. On the basis of the latest international achievements, the new data presented in the Beijing geobiology forum sponsored by Chinese Academy of Sciences in 2013, and the papers in this special issue, here we present an overview of the progress and perspectives on three important frontiers, including geobiology of the critical periods in Earth history, geomicrobes and their responses and feedbacks to global environmental changes, and geobiology in extreme environments. Knowledge is greatly improved about the close relationship of some significant biotic events such as origin, radiation, extinction, and recovery of organisms with the deep Earth processes and the resultant envi- ronmental processes among oceans, land, and atmosphere in the critical periods, although the specific dynamics of the co-evolution between ancient life and paleoenvironments is still largely unknown. A variety of geomicrobial functional groups were found to respond sensitively to paleoenvironmental changes, which enable the establishment of proxies for paleoenvi- ronmental reconstruction, and to play active roles on the Earth environmental changes via elemental biogeochemical cycles and mineral bio-transforrnations, but to be deciphered are the mechanisms of these functional groups that change paleoenvi- ronmental conditions. Microbes of potential geobiology significance were found and isolated from some extreme environments with their biological properties partly understood, but little is known about their geobiological functions to change Earth envi- ronments. The biotic processes to alter or modify the environments are thus proposed to be the very issue geobiology aims to decipher in the future. Geobiology will greatly extend the temporal and spatial scope of biotic research on Earth and beyond. It has great potential of application in the domains of resource exploration and global change. To achieve these aims needs coor- dinative multidisciplinary studies concerning geomicrobiology and related themes, database and modeling of biogeochemical cycles, typical geological environments, and coupling of biological, physical, and chemical processes.
基金financially supported by the National Program on Key Basic Research Project(2018YFA0305604 and 2017YFA0303302)National Natural Science Foundation of China(11774008,381/0401210001)+2 种基金the Key Research Program of the Chinese Academy of Sciences(XDPB08-2)the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics,Tsinghua University(KF201703)China Postdoctoral Science Foundation(130/0401130005)
文摘Topological materials, hosting topological nontrivial electronic band, have attracted widespread attentions. As an application of topology in physics, the discovery and study of topological materials not only enrich the existing theoretical framework of physics, but also provide fertile ground for investigations on low energy excitations, such as Weyl fermions and Majorana fermions, which have not been observed yet as fundamental particles. These quasiparticles with exotic physical properties make topological materials the cutting edge of scientific research and a new favorite of high tech. As a typical example, Majorana fermions, predicted to exist in the edge state of topological superconductors, are proposed to implement topological error-tolerant quantum computers. Thus, the detection of topological superconductivity has become a frontier in condensed matter physics and materials science. Here, we review a way to detect topological superconductivity triggered by the hard point contact: tip-induced superconductivity(TISC) and tip-enhanced superconductivity(TESC). The TISC refers to the superconductivity induced by a non-superconducting tip at the point contact on non-superconducting materials. We take the elaboration of the chief experimental achievement of TISC in topological Dirac semimetal Cd_3As_2 and Weyl semimetal Ta As as key components of this article for detecting topological superconductivity. Moreover, we also briefly introduce the main results of another exotic effect, TESC, in superconducting Au_2Pb and Sr_2RuO_4 single crystals, which are respectively proposed as the candidates of helical topological superconductor and chiral topological superconductor. Related results and the potential mechanism are conducive to improving the comprehension of how to induce and enhance the topological superconductivity.
基金supported by the 111 Project(Grant No.B13001)by the Young Thousand Talents Program from the Organization Department of the Communist Party of China Central Committee
文摘Predictive simulation of engine combustion is key to understanding the underlying complicated physicochemical processes,improving engine performance,and reducing pollutant emissions.Critical issues as turbulence modeling,turbulence-chemistry interaction,and accommodation of detailed chemical kinetics in complex flows remain challenging and essential for highfidelity combustion simulation.This paper reviews the current status of the state-of-the-art large eddy simulation(LES)/probability density function(PDF)/detailed chemistry approach that can address the three challenging modelling issues.PDF as a subgrid model for LES is formulated and the hybrid mesh-particle method for LES/PDF simulations is described.Then the development need in micro-mixing models for the PDF simulations of turbulent premixed combustion is identified.Finally the different acceleration methods for detailed chemistry are reviewed and a combined strategy is proposed for further development.