Cloning and expression analysis of ScBAK1 gene and its alternative spliceosome in sugarcane北大核心CSCD

Alternative splicing (AS) is an important part of regulation of eukaryotic gene expression. BAK1 (Brassinosteroid insensitive1-associated receptor kinase 1) is a specific type of plant serine/threonine protein kinases, and can regulate growth and development and natural immunization. To reveal the responses of sugarcane BAK1 gene to the adverse environment, a ScBAK1 gene and its alternative spliceosome, termed ScBAK1 (GenBank accession number: KP032226) and ScBAK1 S1 (GenBank accession number: KP032227), were cloned from leaf cDNA of Yacheng 05-179 utilizing the methods of electronic cloning and RT-PCR. The open reading frame (ORF) length of ScBAK1/ScBAK1 S1 gene was 1 860bp/1 770bp, encoding 619/589 amino acids residues. The predicted molecular weight of the protein was 69.28 kDa/ 65.76 kDa. Both proteins were located in plasma membrane, estimated as acid, hydrophikic and secretive proteins. Random coil and alpha helix gave priority to extended strand in their secondary structure without beta turn. The most important protein function was cell envelope, secondly biosynthesis of amino acids and cofactors. Real-time quantitative PCR analysis revealed that the expression of sugarcane ScBAK1 S1 gene exhibited the reduced expression trend under smut fungus stress and various abiotic exogenous stresses, including SA, CuCl2, PEG, ABA, NaCl and JA, while the expression of ScBAK1 gene was induced by SA, CuCl2, PEG, NaCl and smut fungus stresses. The phenomenon showed that the absent sequences or amounts of ScBAK1 S1 gene plays a key role in the response of ScBAK1 to the stress of sugarcane smut fungus, osmotic stress and cell growth. The differential expression of ScBAK1 and ScBAK1 S1 lays a foundation for further research on the function of ScBAK1 gene under biotic and abiotic stress.     

Laying a solid foundation for sustainable development in Bolivian mountain villages

In Bolivia, recent decentralisation policies have broadened the participation of local actors in development processes. However, development is far from sustainable, and poverty and natural resources degradation still increase. The challenge is to develop strategies that achieve the genuine participation of poor farmers in natural resources management and sustainable development. The logical strategy, which was developed and validated in five Bolivian mountain villages, is an example. In this strategy, first a solid foundation for sustainable development is laid, with activities focussing on five basic conditions for sustainable development in rural villages: leadership and organisation, responsible participation, effective collaboration, mutual trust and environmental awareness. The results show that the existence of a solid foundation is crucial for the success of other development activities, such as soil and water conservation activities. However, given that 2 years after the project’s withdrawal the firmness of the foundation had slightly weakened, it was concluded that a better integration of these villages in local development processes is essential to profit from the new dynamics. This is especially true for soil and water conservation. To achieve this integration, municipalities—with the support of international development agencies—must be encouraged to invest in laying this solid foundation in rural villages and in facilitating follow-up activities to keep the dynamic process going. This study shows that such investments result in better organised villages, more equality, and the genuine participation of more people in sustainable village development. Effective collaboration and accountability at institutional level are, however, required.     

Comparison of the Vegetation and Seed Bank on Hedge Banks of Different Ages in Brittany,France

The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grimes plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old hedge banks. Differences in the floristic composition of the established plant cover between the recent and old hedge banks were determined by multivariate analyses. The species exclusively found in the seed bank and in the herb cover of recent hedge banks were mainly grassland species, whereas the species that only occurred on old hedge banks tended to be woodland species. The floristic composition of the two compartments (established vegetation and seed bank) was very different. A multivariate analysis revealed that the difference between the composition of the seed banks of recent and old hedge banks was less than that between the composition of the established vegetation and seed bank of hedge banks of the same age. Both seed bank and vegetation of recent hedge banks were dominated by ruderal species, whereas old hedge vegetation was dominated by stress-tolerant woodland species, indicating that mechanically constructed hedge banks may impose limitations on colonization by late woodland species.     

长江三角洲耕地资源态势与保护对策

长江三角洲是我国东部沿海经济最发达的地区,在全国占有十分重要的经济地位。随着经济的发展,资源与环境发生了严重的问题,特别是近年来耕地资源锐减,而后备耕地资源却短缺,人地人粮矛盾更加尖锐,已成为影响这一地区农业持续发展的重要因素。本文分析了这一地区的经济特点与耕地资源的变化态势,并提出了相应的耕地保护措施。首先,要严格控制非农用地,确保基本农田,其次要采用经济手段,建立保护耕地的经济机制;此外,还要     

The Pollution Prevention Act of 1990: A Policy Whose Time Has Come or Symbolic Legislation?

/ In 1990, the United States officially entered the era of pollution prevention with passage of the Pollution Prevention Act. This paper analyzes EPA's implementation of the Pollution Prevention Act from its passage in 1990 to the present. It examines the barriers EPA must overcome if it is to effectively integrate pollution prevention into its existing regulatory structure, including impediments created by statutory and organizational structure, the existing relationship between EPA and the groups it regulates, the fragmented implementation scheme of national environmental regulation, the balancing of conflicting demands advanced by powerful interests, industry's economic and technical concerns, and institutional inertia. It also examines issues such as industry commitment, the limits of prevention, and measurement concerns. The findings suggest that EPA's efforts at shifting to a pollution prevention regulatory ethic that holds primacy over pollution control are mixed. Its organizational structure, statutory authority, and incentives system still reflect a single-medium pollution control focus, appropriations for pollution prevention programs and activities are paltry compared to traditional pollution control programs, and participation in the program is voluntary. Yet, the findings also point to some promising programs that are working to institutionalize a pollution prevention regulatory ethic, and many states appear very committed to the concept.KEY WORDS: Pollution prevention; Source reduction; Pollution control; Alternative regulatory design; Barriers to implementation     

Methane fluxes from artificial wetlands: A global appraisal

Methane emissions make an important contribution to the enhanced greenhouse effect, emissions from rice growing being one of its major anthropogenic sources. The estimation of global fluxes of methane from rice and from coarse fiber production depends on extrapolating observed data across countries and agroclimatic zones: the estimates are therefore imprecise. We present a revised estimate of global emissions of 96 Tg CH₄/yr, given 1991 rice areas, and 1991 production data for those tropical coarse fibers that also produce methane under anaerobic conditions. This is higher than many previous studies, which systematically underestimated the fluxes from tropical countries. As the world's population increases, the demand for rice will rise. This demand can only be satisfied through greater rice production, either by bringing new areas into rice growing or by using the present area more intensively. Strategies based on improved water management and fertilizer use will allow increased rice production and yields and reduce the methane flux per unit or rice production.     

发展我国森林生态旅游的对策思考

作者以生态旅游理论为基础，分析了我国森林生态旅游的发展状况，并以加入WTO为背景从中找出存在的问题，进而提出入世后推进我国森林生态旅游发展的对策。     

基于模式生物秀丽隐杆线虫的环境污染物生殖毒性研究进展

由于人类社会的发展,环境污染也越来越严重,研究环境污染物对生态及人类健康的影响极为重要。生殖系统是人和动物繁衍后代的重要系统,常见环境污染物对生殖系统的影响正引起研究人员的广泛关注。秀丽隐杆线虫具有身体透明、品系丰富和遗传背景清楚等优点,为生殖毒理学研究提供了一个便利的平台。以秀丽隐杆线虫为模型已对多种环境污染物的生殖毒性进行了评价。本文重点叙述了重金属、纳米材料、有机物等化学污染,辐射、磁场等物理污染,以及病毒等生物污染对秀丽线虫生殖系统的影响,并归纳讨论了环境污染物造成生殖功能障碍的几种主要机制,如氧化应激、DNA损伤、内质网应激以及神经损伤等,但不同类型污染物的毒性效应与其自身的物化性质紧密相关。环境污染物诱导的生殖毒性中不同响应机制之间的关联性、不同发育阶段的敏感性差异、污染物的传代效应以及有效的缓解方式的筛选等都有待进一步的开展。     

突发事件下多种信息交互传播的动力机制与调控策略

针对突发事件下多种信息共存情境中信息交互传播的调控问题,首先界定了该情境中“涌现→传播”过程的组成要素,建立了信息交互关系框架及其系统动力学模型;其次,通过设计和仿真基础情景,将仿真结果与案例进行对比,检验模型的模拟趋势与现实状况的一致性;最后,通过设计和仿真实验情景,考查决策者的关键可控因素对系统演化的影响。研究结果表明:官方渠道所发布信息的可信度、平均个体传播量及群体的立场认知水平,与相信和传播官方渠道信息的人数均正相关,而与相信和传播民间渠道信息的人数均负相关;对各群体数量演化影响的显著性而言,官方渠道信息的平均个体传播量最高,官方渠道信息的可信度次之,群体的立场认知水平较低。     

室内环境中持久性卤代有机污染物的人体暴露及潜在生殖健康影响

卤代持久性有机污染物(Hal-POPs),如多溴联苯醚(PBDEs)、多氯联苯(PCBs)、滴滴涕(DDT)等是环境中广泛存在的全球性有机污染物,同时它们又是内分泌干扰物,是威胁人类生殖健康的重要因素之一。由于人们每天约有80%以上的时间在室内度过,且室内环境是Hal-POPs人体暴露的主要来源之一,因此室内环境中Hal-POPs对人体内分泌系统的干扰作用及其机理等问题亟待研究,但目前这方面的研究很有限。本文通过综述Hal-POPs在室内环境中的赋存水平和在人体体内的负荷水平及其半衰期,探讨了其对人体内分泌系统尤其是男性生殖健康的影响情况及其可能的机理,并分析了目前研究的不足之处及研究前景,为进一步开展这方面的研究提供借鉴。