Forensic Ecotoxicology: Establishing Causality between Contaminants and Biological Effects in Field Studies

Twelve papers in this series were derived from two conference sessions focusing on causality in field studies. Eight of these papers involve case studies examining biological effects of chemical contaminants in field situations. Using a weight-of-evidence approach, these case studies were evaluated against seven proposed criteria for establishing causality. The seven criteria were: strength of association; consistency of association; specificity of association; time order; biological gradient; experimental evidence; and biological plausibility. One of these seven criteria, ‘specificity of association’ was found to be of little utility for establishing causality in these field studies. The case studies are presented in approximate order of increasing levels of biological organization (i.e., going from endpoints at the suborganismal level to endpoints at the population or community level). In case studies examining higher levels of biological organization, it appears that the ‘biological gradient’ criterion was also not useful in establishing causality. These results, together with suggestions from other papers in the series, are used to recommend a set of modified criteria for establishing causality in field studies of the biological effects of chemical contaminants.     

The molecular mechanisms that underpin the biological benefits of full-spectrum cannabis extract in the treatment of neuropathic pain and inflammation

Cannabis has been shown to be beneficial in the treatment of pain and inflammatory diseases. The biological effect of cannabis is mainly attributed to two major cannabinoids, tetrahydrocannabinol and cannabidiol. In the majority of studies to-date, a purified tetrahydrocannabinol and cannabidiol alone or in combination have been extensively examined in many studies for the treatment of numerous disorders including pain and inflammation. However, few studies have investigated the biological benefits of full-spectrum cannabis plant extract. Given that cannabis is known to generate a large number of cannabinoids along with numerous other biologically relevant products including terpenes, studies involving purified tetrahydrocannabinol and/or cannabidiol do not consider the potential biological benefits of the full-spectrum cannabis extracts. This may be especially true in the case of cannabis as a potential treatment of pain and inflammation. Herein, we review the pre-clinical physiological and molecular mechanisms in biological systems that are affected by cannabis.     

Determining protein–protein functional associations by functional rules based on gene ontology and KEGG pathway

Protein–protein interactions (PPIs) describe the direct physical contact of two proteins that usually results in specific biological functions or regulatory processes. The characterization and study of PPIs through the investigation of their pattern and principle have remained a question in biological studies. Various experimental and computational methods have been used for PPI studies, but most of them are based on the sequence similarity with current validated PPI participators or cellular localization patterns. Most methods ignore the fact that PPIs are defined by their specific biological functions. In this study, we constructed a novel rule-based computational method using gene ontology and KEGG pathway annotation of PPI participators that correspond to the complicated biological effects of PPIs. Our newly presented computational method identified a group of biological functions that are tightly associated with PPIs and provided a new function-based tool for PPI studies in a rule manner.     

生物运动识别的信息加工机制

识别其他生物体的运动对于个体的生存和社会交互都有极为重要的意义.本文首先基于生物运动识别的行为学、心理物理学、脑损伤和精神障碍研究介绍了生物运动识别的一些特性和影响因素;然后基于神经影像学、脑损伤和神经电生理学研究从视觉系统背腹侧双通路加工的角度,梳理了其信息加工机制的进展;最后对生物运动识别信息加工神经机制的研究方向提出了一点建议,并指出研究过程中需要注意的问题.     

Managing biological control services through multi‐trophic trait interactions: review and guidelines for implementation at local and landscape scales

Ecological studies are increasingly moving towards trait‐based approaches, as the evidence mounts that functions, as opposed to taxonomy, drive ecosystem service delivery. Among ecosystem services, biological control has been somewhat overlooked in functional ecological studies. This is surprising given that, over recent decades, much of biological control research has been focused on identifying the multiple characteristics (traits) of species that influence trophic interactions. These traits are especially well developed for interactions between arthropods and flowers – important for biological control, as floral resources can provide natural enemies with nutritional supplements, which can dramatically increase biological control efficiency. Traits that underpin the biological control potential of a community and that drive the response of arthropods to environmental filters, from local to landscape‐level conditions, are also emerging from recent empirical studies. We present an overview of the traits that have been identified to (i) drive trophic interactions, especially between plants and biological control agents through determining access to floral resources and enhancing longevity and fecundity of natural enemies, (ii) affect the biological control services provided by arthropods, and (iii) limit the response of arthropods to environmental filters, ranging from local management practices to landscape‐level simplification. We use this review as a platform to outline opportunities and guidelines for future trait‐based studies focused on the enhancement of biological control services.     

生物固氮在我国农业生产中的研究现状及发展对策

简述了生物固氦在我国农业生产中3个热点的研究现状:提高现有固氦生物的固氦能力、化学模拟固氦酶、固氦微生物的生物工程,同时提出了生物固氦在令后生态农业中的发展对策。     

Statistical aspects of the planning and analysis of collaborative studies on biological standards

Statistical principles play a central role in the planning and analysis of collaborative studies on biological standards. These studies are carried out to assess the suitability of proposed biological standards, which should be demonstrated to provide valid and reproducible measurements of biological potency, and to assign units of activity (for example, by calibration against an existing standard). Guidelines have been published by the World Health Organization (WHO Tech Rep Ser 1978: 626: 101-141) describing the technical and general aspects of setting up biological standards and organizing collaborative studies. This paper, which is complementary to the WHO guidelines, expands on the statistical points which need to be considered. The general design of the study, the design of individual assays, the statistical analysis of the raw data, and the presentation of the results are described.     

Conversion of microbial rhodopsins: insights into functionally essential elements and rational protein engineering

Technological progress has enabled the successful application of functional conversion to a variety of biological molecules, such as nucleotides and proteins. Such studies have revealed the functionally essential elements of these engineered molecules, which are difficult to characterize at the level of an individual molecule. The functional conversion of biological molecules has also provided a strategy for their rational and atomistic design. The engineered molecules can be used in studies to improve our understanding of their biological functions and to develop protein-based tools. In this review, we introduce the functional conversion of membrane-embedded photoreceptive retinylidene proteins (also called rhodopsins) and discuss these proteins mainly on the basis of results obtained from our own studies. This information provides insights into the molecular mechanism of light-induced protein functions and their use in optogenetics, a technology which involves the use of light to control biological activities.     

Biorobotic approaches to the study of motor systems

Biorobotics is a promising new area of research at the interface between biology and robotics. Robots can either be used as physical models of biological systems or be directly inspired by biological studies. A great deal of progress has recently been made in biorobotic studies of locomotion, orientation, and vertebrate arm control.     

Flow cytometry in oceanography 1989--1999: environmental challenges and research trends.

BACKGROUND: The present review is based on the identification of four major environmental crises that have been approached from a biological oceanographic viewpoint. These crises are the release of contaminants in near shore marine waters, the collapse of marine resources that were renewable until recently, the loss of biodiversity, and global climate change METHODS: The review examines the contribution of cytometry-based biological oceanography to the resolution of the four environmental crises. Using a database of 302 papers, flow cytometric (FCM) studies in biological oceanography over the 1989--1999 decade are examined. Future biological oceanographic applications of FCM are discussed. RESULTS: Most of the published FCM oceanographic studies focus on phytoplankton and bacterioplankton. Analysis of our 1989-1999 database shows the predominance of studies dedicated to phytoplankton (77%), followed by heterotrophic bacteria (21%). The latter progressively increased over the last decade, together with the improved understanding of the biogeochemical and trophic roles of marine bacteria. Most studies on these two microorganisms were conducted in vitro until 1996, after which the trend reversed in favor of in situ research. The most investigated areas were those with major international sampling efforts, related to the changing climate. Concerning environmental topics, 62% of papers on phytoplankton and bacterioplankton focused on the structure of microbial communities and fluxes (e.g., production, grazing); this provides the basis for biological oceanographic studies on resources and climate change. CONCLUSIONS: Future progress in the biological oceanographic use of FCM will likely fall into two categories, i.e., applications where FCM will be combined with the development of other methods and those where FCM will be the main analytical tool. It is expected that FCM and other cytometric approaches will improve the ability of biological oceanography to address the major environmental challenges that are confronting human societies.     

How do biological systems discriminate among physically similar ions?

This paper reviews the history of understanding how biological systems can discriminate so strikingly among physically similar ions, especially alkali cations. Appreciation of qualitative regularities ("permitted sequences") and quantitative regularities ("selectivity isotherms") in ion selectivity grew first from studies of ion exchangers and glass electrodes, then of biological systems such as enzymes and cell membranes, and most recently of lipid bilayers doped with model pores and carriers. Discrimination of ions depends on both electrostatic and steric forces. "Black-box" studies on intact biological membranes have in some cases yielded molecular clues to the structure of the actual biological pores and carriers. Major current problems involve the extraction of these molecules; how to do it, what to do when it is achieved, and how (and if) it is relevant to the central problems of membrane function. Further advances are expected soon from studies of rate barriers within membranes, of voltage-dependent ("excitable") conducting channels, and of increasingly complex model systems and biological membranes.     

A review of the integration of classical biological control with other techniques to manage invasive weeds in natural areas and rangelands

Integrating classical biological control with other management techniques such as herbicide, fire, mechanical control, grazing, or plant competition, can be the most effective way to manage invasive weeds in natural areas and rangelands. Biological control agents can be protected from potential negative impacts of these weed control methods through untreated refugia or by applying the treatment at a time when the agent is not vulnerable. A literature review of experiments that integrated biological control with other management strategies from 1987 to 2017 yielded 39 terrestrial and 16 aquatic studies. The tactics most frequently integrated with biological control were herbicide applications and plant competition. Despite numerous examples of successful programs and calls for more widespread integration of biological control with other weed management strategies, there was no increase in the number of studies reported annually over time. Additional studies investigating the ecological and economic benefits of integrated weed management are needed.     

天然产物黄檀内酯的研究进展

本文概述了目前已发表的天然产物黄檀内酯在植物中分布、生物合成、全合成及生物活性的研究进展。     

分子生物学技术在双翅目实蝇科昆虫系统发育研究中的应用

分子生物学技术如同工酶电泳、RFLP、RAPD、核酸序列分析、微卫星DNA和探针杂交等,在实蝇科昆虫系统发育研究中具有重要作用。利用这些技术对实蝇种群进行系统发育研究,揭示其亲缘及进化关系,从生命本质上寻找实蝇种群间的内在联系。文章综述上述几种分子生物学技术在实蝇科昆虫核酸结构、种内和种间的亲缘及进化关系等方面的研究进展,分析在应用中存在的问题,展望这些分子生物学技术在实蝇科昆虫系统发育中的应用前景。     

Algorithms in nature: the convergence of systems biology and computational thinking

Computer science and biology have enjoyed a long and fruitful relationship for decades. Biologists rely on computational methods to analyze and integrate large data sets, while several computational methods were inspired by the high‐level design principles of biological systems. Recently, these two directions have been converging. In this review, we argue that thinking computationally about biological processes may lead to more accurate models, which in turn can be used to improve the design of algorithms. We discuss the similar mechanisms and requirements shared by computational and biological processes and then present several recent studies that apply this joint analysis strategy to problems related to coordination, network analysis, and tracking and vision. We also discuss additional biological processes that can be studied in a similar manner and link them to potential computational problems. With the rapid accumulation of data detailing the inner workings of biological systems, we expect this direction of coupling biological and computational studies to greatly expand in the future.     

Wie Fliegen an die Decke gehen

How do flies walk on the ceiling? Many functional solutions for adhering, gluing, and interlocking have evolved independently in different lineages of organisms. Since the diversity of such biological structures and their importance for understanding biology of particular organisms is large, there is a strong need for comparative structural and functional studies. This contribution summarises the original and literature data and proposes classification of biological attachment systems according to several principles. We show a biomimetic potential of studies on biological attachment devices for the further use in technological developments.     

沙棘的生物学与生态学特性

沙棘生物学与生态学特性一直是众多学者关注的焦点之一,众多学者在叶表皮毛特征、根系解剖结构和生物固氮方面已经取得了基本一致的看法,但在水分生理生态和种群坟散方面尚存争议或不理解之处。这主要是由于忽视了沙棘无性系植物种群的生理整合作用和觅养行为。因此,今后应该从无性系生长可塑性调节和分株间资源共享特征出发,进一步探讨沙棘的抗旱机理和生态适应对策。     

Indirect nontarget effects of host-specific biological control agents: Implications for biological control

Classical biological control of weeds currently operates under the assumption that biological control agents are safe (i.e., low risk) if they do not directly attack nontarget species. However, recent studies indicate that even highly host-specific biological control agents can impact nontarget species through indirect effects. This finding has profound implications for biological control. To better understand the causes of these interactions and their implications, we evaluate recent case studies of indirect nontarget effects of biological control agents in the context of theoretical work in community ecology. We find that although particular indirect nontarget effects are extremely difficult to predict, all indirect nontarget effects of host specific biological control agents derive from the nature and strength of the interaction between the biological control agent and the pest. Additionally, recent theoretical work suggests that the degree of impact of a biological control agent on nontarget species is proportional to the agent’s abundance, which will be highest for moderately successful control agents. Therefore, the key to safeguarding against indirect nontarget effects of host-specific biological control agents is to ensure the biological control agents are not only host specific, but also efficacious. Biological control agents that greatly reduce their target species while remaining host-specific will reduce their own populations through density-dependent feedbacks that minimize risks to nontarget species.