植物修复重金属与多环芳烃污染土壤强化措施研究进展

重金属和多环芳烃是土壤环境中的重要污染物，其复合污染土壤的修复已成为环境科学研究的热点问题。植物修复技术是目前修复土壤复合污染重要方法之一，但植物本身修复能力有限，需借助化学、微生物、基因工程等手段对其修复效果进行强化。本文对国内外近几年来植物修复重金属-多环芳烃复合污染强化措施研究成果进行综述，并重点讨论了植物根际生长促进菌及菌根在强化修复中的应用，在此基础上对未来该领域需要深入研究的科学问题进行了阐述。     

我国污染土壤生物修复技术研究现状及发展展望

以文献统计的方式对2006~2015年国内学者在中国知网和Web of science中发表的相关文献进行统计分析,综述了我国污染土壤生物修复技术的10年研究进展。结果显示:近10年我国土壤生物修复技术的研究热度不断上升,主要研究对象为重金属污染土壤和有机物污染土壤,总体分为机理研究和试验研究,且后者居多。在此基础上,本文简要介绍了当前主要研究的植物修复技术、微生物修复技术、动物修复技术、生物材料修复技术、生物组合修复技术及物理、化学、生物联合修复技术6种生物修复技术的原理、优缺点及研究现状等内容,并指出了未来生物修复技术在修复原理、针对性、经济性、风险、强化措施、应用范围等方面的发展方向。     

沉积型微生物燃料电池效能的影响因素研究进展

沉积型微生物燃料电池是一种利用微生物催化氧化作用处理水体沉积物的原位修复方法。本文综述了影响其效能的影响因素:电极、底物的预处理和传质、水体、微生物及外电阻,并对如何从这些方面进一步提高效能进行了展望。     

世界植物园的现状与展望

世界植物园的发展史，是一部人类加深认识、进行保护和扩大利用植物的历史。随着植物园数量的增长，植物园可分为综合性、园林和观赏园艺、经济植物及种质保存等类型。当前植物瞻的任务主要为植物多样性的保护、植物资源利用、展示教育与咨询和科学研究。由于植物资源的竞争更加激烈但规范化、管理更加现代化与科学化、植物园更加开放与联合，展望植物园今后的发展，可能将在植物园学和科学植物园、专类园建设及群落建园、植物园信息管理系统、虚拟植物园与科普、植物园网络化、推动植物资源可持续利用等方面不断加强与完善。     

镉污染土壤的植物修复研究进展与展望

近年来,重金属镉(Cd)及其复合污染问题越来越受到人们的关注.Cd污染土壤的植物修复技术因其具有治理成本的低廉性、环境美学的兼容性和治理过程的原位性等优势,随之成为具有广泛应用前景的技术.本文概述了Cd超积累植物的筛选及耐性机理与修复潜力的评价等方面的国内外进展,总结了Cd-重金属复合污染土壤、Cd-有机物复合污染土壤的植物修复相关的重要工作,着重评述了Cd复合污染土壤的化学强化、农业生态强化及其它方法的研发现状,展望了这一领域今后的重点研究内容和重要发展方向.     

德美科学家借助植物实验获得癌症研究新进展

德国和美国科学家日前联合进行了一项研究，成功地发现了发育基因“RAD51”在模式植物拟南芥中的特性机理。科学家说，由于该基因与遗传行为及肿瘤形成具有密切关系，因此新成果有望为人类征服癌症带来帮助。     

植物硫苷-黑芥子酶系统对环境胁迫的响应

硫苷-黑芥子酶系统是植物中一种特有的底物酶系统,其水解产物具有高度生物活性,该系统对植物的生长发育、生长素微调以及植物的防御保护等均有重要意义.目前对植物硫苷-黑芥子酶系统对环境胁迫的响应的研究多为对硫苷的研究,而对系统相关物质研究较少.本文对硫苷-黑芥子酶系统做了简单介绍,并对植物硫苷-黑芥子酶系统对病虫害和酸雨、水、温度、盐、重金属胁迫下的响应进行了综述.     

种植模式对稻田土壤微生物数量及活度的影响

为了明确种植模式对稻田土壤微生物的影响情况，进行了少耕和翻耕时不同种植模式对稻田土壤微生物数量及活度的影响研究，结果表明：种植马铃薯、紫云英、黑麦草、油菜、小黑麦等冬季作物能够不同程度的影响土壤中微生物的数量与活度，影响程度可以表示为马铃薯〉黑麦草〉小黑麦〉紫云英〉油菜〉冬闲。在晚稻收割期，少耕土壤中的好气性细菌、厌气性细菌、真菌、放线菌数量都多于翻耕土壤。早稻收割期翻耕比少耕的微生物活度略高，而晚稻收割期翻耕比少耕的微生物略低，这与所测的几类微生物数量的基本变化规律是一致的。少耕能激活土壤中的微生物，改良土壤。     

法国继续推进动物和植物基因组研究计划

在开展以了解人类基因为目的人类基因组计划(Genethon)之后 ,法国决定投入大笔资金 ,研究植物基因组 ,最近又开始了动物基因组的研究。法国的研究计划联合了公共和私营领域的研究力量 ,投入了大量的资金。第一批成果即将进入应用。1999年初 ,法国启动了植物基因组研究计划 (Geno plante) ,正式开始对植物基因的研究。这是一个大型的研究计划 ,联合了公共和私营领域的研究力量 ,目的是要识别包含在动物和植物染色体中的遗传信息。计划分为五年实行 ,预算为 2 2亿欧元。从投入的研究手段来看 ,这是除美国之外的世界第二大研究计划 ,在欧洲则…     

电化学红外光谱解析五氯酚的阴极微生物还原脱氯机制

通过构建基于恒电位(0,-200,-500,-800 mV vs. SCE)的生物电化学系统,考查了污染土壤五氯酚(pentachlorophenol, PCP)脱氯效率、阴极生物膜的电子吸收能力以及电活性物质种类;借助原位电化学红外光谱和二维相关光谱手段解析了参与PCP阴极还原脱氯的氧化还原活性基团及可能的电子传递途径;通过16S r RNA基因测序技术分析了微生物群落结构对不同恒电位的响应变化.结果表明:(1)-500 mV电位刺激下的PCP微生物还原脱氯效率分别是0和-200 m V电位下的5倍以及-800 mV的1.8倍,最高生物电流(约45μA)也高于其他电位处理(0～35μA),说明-500 mV电位刺激下的阴极生物膜电子吸收能力和PCP还原脱氯效率明显优于其他电位处理;(2)-500 mV电位下的CV曲线中氧化还原峰位于-250和-450 mV(vs. SCE),该物质可能是参与PCP还原脱氯的主要电化学活性物质;(3)-200,-500和-800 mV电位下形成的电活性生物膜参与PCP还原脱氯,对阴极电子传递响应最迅速的主要氧化还原活性成分分别是氨基III、细胞色素和腐殖酸,-500 mV电位下细胞色素可能介导了更高效的电子传递,从而导致PCP的微生物还原脱氯效率明显优于其他电位处理;(4)不同电位下微生物群落结构差异显著,-500 mV电位下的优势微生物为丛毛单胞菌(Comamonadaceae),可能是驱动PCP阴极还原脱氯的重要功能微生物.该研究初步解析了参与PCP阴极还原脱氯的优势微生物及重要氧化还原活性成分,为PCP的高效降解及污染环境的治理提供了理论支撑.     

What is the environment in environmental health research? Perspectives from the ethics of science

Environmental health research produces scientific knowledge about environmental hazards crucial for public health and environmental justice movements that seek to prevent or reduce exposure to these hazards. The environment in environmental health research is conceptualized as the range of possible social, biological, chemical, and/or physical hazards or risks to human health, some of which merit study due to factors such as their probability and severity, the feasibility of their remediation, and injustice in their distribution. This paper explores the ethics of identifying the relevant environment for environmental health research, as judgments involved in defining an environmental hazard or risk, judgments of that hazard or risk's probability, severity, and/or injustice, as well as the feasibility of its remediation, all ought to appeal to non-epistemic as well as epistemic values. I illustrate by discussing the case of environmental lead, a housing-related hazard that remains unjustly distributed by race and class and is particularly dangerous to children. Examining a controversy in environmental health research ethics where researchers tested multiple levels of lead abatement in lead-contaminated households, I argue that the broader perspective on the ethics of environmental health research provided in the first part of this paper may have helped prevent this controversy.     

The cellular immune response to heat shock proteins.

T lymphocytes, which are central to almost every immune response, frequently recognize microbial hsp60. Such cells could provide an early defense mechanism against pathogenic microbes. However, T cells also recognize epitopes of hsp60 shared by microbe and host. Not only conventional alpha/beta T cells respond to hsp60; gamma/delta T cells do so, as well. In fact, certain gamma/delta T cells seem to have a particular preference for this molecule. Recognition of stressed host cells expressing hsp60 could facilitate the scavenger function of the T cell system. On the other hand, such recognition could be involved in autoimmune disease.     

陕北地区生态修复与粮食安全分析

生态修复是指利用自然界的自我修复能力,在适当人工措施辅助下,恢复生态系统原有的保持水土、调节小气候、维护生物多样性的生态功能和开发利用等经济功能。生态修复工程给黄土丘陵区提供了一次难得的生态重建历史机遇。粮食供需的总量平衡是我国面临的巨大的问题．且在人口净增长达到由正变负的拐点之前,问题的艰巨性将与日俱增。基于粮食问题是我国的根本问题,本文以生态修复学的基本原理为指导,利用生态经济学的基本观点,回顾了黄土丘陵区产的发展历史,探讨了生态修复过程中的粮食生产潜力;在此基础上,根据当地经济发展规划和远景目标,提出了相应的发展对策：稳住粮田面积、强化基础建设、加大投入力度、积极推动粮食产业化、控制人口增长、提高思想认识。     

Molecular basis of mycobacterial survival in macrophages

Macrophages play an essential role in the immune system by ingesting and degrading invading pathogens, initiating an inflammatory response and instructing adaptive immune cells, and resolving inflammation to restore homeostasis. More interesting is the fact that some bacteria have evolved to use macrophages as a natural habitat and tools of spread in the host, e.g., Mycobacterium tuberculosis (Mtb) and some non-tuberculous mycobacteria (NTM). Mtb is considered one of humanity’s most successful pathogens and is the causal agent of tuberculosis, while NTMs cause opportunistic infections all of which are of significant public health concern. Here, we describe mechanisms by which intracellular pathogens, with an emphasis on mycobacteria, manipulate macrophage functions to circumvent killing and live inside these cells even under considerable immunological pressure. Such macrophage functions include the selective evasion or engagement of pattern recognition receptors, production of cytokines, reactive oxygen and nitrogen species, phagosome maturation, as well as other killing mechanisms like autophagy and cell death. A clear understanding of host responses elicited by a specific pathogen and strategies employed by the microbe to evade or exploit these is of significant importance for the development of effective vaccines and targeted immunotherapy against persistent intracellular infections like tuberculosis.     

Human bodies as chemical sensors: A history of biomonitoring for environmental health and regulation

The testing of human blood and urine for signs of chemical exposure has become the “gold standard” of environmental public health, leading to ongoing population studies in the US and Europe. Such methods first emerged over a century ago in medical and occupational contexts, as a means to calibrate drug doses for patients and prevent injury to workers from chemical or radiation exposure. This paper analyzes how human bodies have come to serve as unconscious sensors of their environments: containers of chemical information determined by expert testers. As seen in the case of lead testing in the US, these bodily traces of contaminants can provide compelling evidence about dangerous exposures in everyday life, useful in achieving stronger regulation of industry. The use of genetic testing of workers by Dow Chemical provides an example of industry itself undertaking biomonitoring, though the company discontinued the program at the same time its studies indicated chromosomal damage in connection with occupational exposure to certain chemicals. In this case and others, biomonitoring raises complex questions about informing subjects, interpreting exposure in the many cases for which health effects at low doses are unknown, and who should take responsibility for protection, compensation, or remediation. Further, the history of biomonitoring complicates how we understand human ‘experience’ of the global environment by pointing to the role of non-sensory—yet detectable—bodily exposures.     

The cellular immune response to heat shock proteins

T lymphocytes, which are central to almost every immune response, frequently recognize microbial hsp60. Such cells could provide an early defense mechanism against pathogenic microbes. However, T cells also recognize epitopes of hsp60 shared by microbe and host. Not only conventional / T cells respond to hsp60; / T cells do so, as well. In fact, certain / T cells seem to have a particular preference for this molecule. Recognition of stressed host cells expressing hsp60 could facilitate the scavenger function of the T cell system. On the other hand, such recognition could be involved in autoimmune disease.     

两种新生大鼠皮质发育障碍模型的差异基因表达谱研究

目的研究两种不同的方法构建皮质发育障碍(DCDs)动物模型中的共同差异表达基因,为进一步研究DCDs形成机制提供基因水平筛选的研究平台。方法用两种方法制备DCDs模型:①射线损伤模型(射线组):采用剂量为1.45 Gy的γ射线照射妊娠15 d的SD大鼠制作子代大鼠DCDs模型;②卡莫司汀(BCNU)药物损伤模型(药物组):妊娠15 d的SD大鼠,腹腔注射BCNU制作子代大鼠DCDs模型。同时设正常对照组。对两种DCDs模型的子代新生鼠(P0)全脑做基因芯片扫描,结果与正常对照组比较,获得两种模型共有的差异基因。结果射线组大鼠与正常比较得到170个差异基因,其中25个上调,145个下调;药物组大鼠与正常比较得到259个差异基因,其中67个上调,192个下调。两组重合的基因共54个,其中3个上调,51个下调。结论皮质发育障碍是一个复杂的病理过程,本实验运用基因芯片技术,对两种不同方法构建的DCDs模型进行了研究,获得两种DCDs模型共有的基因差异表达谱,为进一步研究DCDs形成机制提供了分子生物学平台。     

The many faces of unification and pluralism in economics: The case of Paul Samuelson's Foundations of Economic Analysis

The history of modern economics abounds with pleas for more pluralism as well as pleas for more unification. These seem to be contradictory goals, suggesting that pluralism and unification are mutually exclusive, or at least that they involve trade-offs with more of one necessarily being traded off against less of the other. This paper will use the example of Paul Samuelson's Foundations of Economic Analysis (1947) to argue that the relationship between pluralism and unification is often more complex than this simple dichotomy suggests. In particular, Samuelson's Foundations is invariably presented as a key text in the unification of modern economics during the middle of the twentieth century; and in many ways that is entirely correct. But Samuelson's unification was not at the theoretical (causal and explanatory) level, but rather at the purely mathematical derivational level. Although this fact is recognized in the literature on Samuelson, what seems to be less recognized is that for Samuelson, much of the motivation for this unification was pluralist in spirit: not to narrow scientific economics into one single theory, but rather to allow for more than one theory to co-exist under a single unified derivational technique. This hidden pluralism will be discussed in detail. The paper concludes with a discussion of the implications for more recent developments in economics.     

Distribution of metals in annual rings of the beech (Fagus sylvatica) as an expression of environmental changes

Summary Annual rings of 140–160-year-old beeches (Fagus sylvatica) from St. Ingbert, Saarland (FRG) were prepared and analyzed for 14 metals by atomic absorption spectroscopy. According to the chronological variations of their concentrations, the elements could be divided into three groups: 1) Metals without any tendency for chronological changes. This was established for Na, K, Cu, Cr, Co, Ni, Pb, and Cd. 2) Metals with a recent decrease of their concentrations, appropriate for Ca, Mg, Mn, and Zn. 3) Metals with a recent tendency to increase, e.g. Fe and Al. These variations are discussed in connection with the industrial history of the Saarland region and the influence of acid immissions which may alter the soil and thereby the trace element metabolism of the trees with consequences for the vitality of the plants.