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1.
All organisms on Earth have evolved biological rhythms to face alternation of periods of favorable and unfavorable environmental conditions, at various temporal scales. Diapause is a state of seasonal dormancy adapted to recurring periods of adverse environmental conditions and triggered by biotic and abiotic factors that precede the arrival of these conditions. Several monographs already review the mechanisms of diapause expression in arthropods, from initiation to termination phases. Rather than adding another review to the literature on this topic, this paper primarily aims to link past concepts on seasonal strategies with new perspective on diapause research in arthropods. By focusing on insects, I examine the legacy of diapause history research in terrestrial arthropods since antiquity but mostly over the past 3 centuries, its contribution to the understanding of insect seasonal ecology, and I explore some of the reasons why it is still relevant to study diapause. I highlight some of the topical issues on which current work focuses to better understand and integrate arthropod diapause with their ecology, especially in the climate change context and for the provision of ecosystem services. 相似文献
2.
In this study, Canadian healthcare ethics consultants describe their use of ethics decision‐making frameworks. Our research finds that ethics consultants in Canada use multi‐purpose ethics decision‐making frameworks, as well as targeted frameworks that focus on reaching an ethical resolution to a particular healthcare issue, such as adverse event reporting, or difficult triage scenarios. Several interviewees mention the influence that the accreditation process in Canadian healthcare organizations has on the adoption and use of such frameworks. Some of the ethics consultants we interviewed also report on their reluctance to use these tools. Limited empirical work has been done previously on the use of ethics decision‐making frameworks. This study begins to fill this gap in our understanding of the work of healthcare ethics consultants. 相似文献
3.
Clinical trials of novel agents often present several layers of ethical challenge. Because time and resources for ethical and safety review are limited, how investigators, IRBs, and regulators allocate attention to a trial's various safety dimensions itself represents a critical ethical question. In what follows, I use the example of a Parkinson's disease gene transfer trial to show how risks involving unknown probabilities or outcomes (ambiguity), might sometimes draw attention away from risks that involve known probabilities or outcomes. This potentially undermines the goal of 'systematic and nonarbitrary analysis of risk' during ethical review. To counteract the possible effects of such attention biases, I propose that reviewers develop 'cognitive aids' like lists and, where appropriate, set aside time to discuss non-ambiguous risks. I also propose further research for addressing and understanding how attention allocation, emotion, and ambiguity influence ethical decision-making. 相似文献
4.
During the last three decades, developmental research has increasingly emphasized the relevance of peer relations in children’s
socialization. However, most studies of child development still focus upon individual differences in social status, tacitly
neglecting relational constraints inherent in the ecology of the peer group. In contrast, socioethological approaches have
stressed that natural groups provide a variety of distinct social roles that may have a differential impact upon individual
growth and development. However, ethological analyses have often been limited to aggressive relations and group dominance
structures. Comparable studies of affiliative organization have been hampered by the paucity of models for the study of cohesive
social structure, only recently having begun to overcome this obstacle. A potential third dimension of preschool peer group
ethology, object use, has been relatively neglected in studies of peer relations. However, recent research suggests that object
use is a salient and important component of the social world of the young child. This article reviews methodology and recent
findings in the area of peer relations and discusses the developmental implications of this work.
Received: 8 December 1998 / Received in revised form: 26 March 1999 / Accepted: 31 March 1999 相似文献
5.
抗生索被长期大量地用于人和动物的疾病治疗,并以亚治疗剂量添加于动物饲料长期用于动物疾病的预防和促进生长,大部分抗生紊不能完全被机体吸收,而有高达85%以上抗生素以原形或代谢物形式经由病人和畜禽粪尿排人环境,经不同途径对土壤和水体造成污染。最近研究显示在城市废水和表面水中检测到了抗生索的存在。但关于抗生素在环境中的分布、迁移和稳定性等的研究资料很少。环境中的抗生素会对环境生态系统包括细菌、水生生物、土壤生物和植物等产生危害,并产生大量耐药菌,对人类健康构成威胁。为评估抗生素在环境中潜在的危害,就抗生素在环境中的分布、转归及对环境和人的危害等方面进行综述,并对今后的研究方向作了探索。 相似文献
6.
This issue of Human Ecology focuses on the interrelated nature of crisis in human and environmental systems and argues that the right to a healthy environment is a fundamental human right. In this article I present a conceptual framework for the human rights and environment special issue, followed by a brief review of significant insights offered by each contributor. Collectively the cases presented in this issue explore connections between international and national policy, government action or sanctioned action, and human environmental crises. Cultural notions are seen to play a key role in influencing social relations, legitimizing power relations, and justifying the production and reproduction of human environmental crises. And finally, these cases explore the ways in which political, economic, and cultural forces influence and at times inhibit efforts to respond to human environmental crises. 相似文献
7.
随着分子生物学技术方法的快速发展,动物肠道微生物已成为医学、动物生理学与微生物生态学等研究领域热点。土壤动物种类繁多,分布广泛,其作为陆地生态系统重要组分,是驱动生态系统功能的关键因子。土壤动物体内的微生物由于与宿主长期共存,在与宿主协同进化中形成了丰富多样的群落结构,能够影响土壤动物本身的健康,进而介导土壤动物生态功能的实现。近些年,土壤动物肠道微生物工作方兴未艾,日渐得到重视。总结了四个部分内容:1)首先总结了土壤动物肠道微生物多样性领域的研究现状,该领域年发文量逐年增长,且近十年增长快速。土壤模式生物肠道微生物多样性研究较多且更为深入。土壤动物肠道微生物多样性组成与驱动机制、共存机制及群落构建的理论研究是该领域前沿;2)进而展示了土壤动物肠道微生物多样性组成和研究方法,土壤动物肠道菌群组成以变形菌门、厚壁菌门、放线菌门和拟杆菌门为主。早期工作基于传统分离培养,近年来新一代测序技术推动了该领域发展;3)接着关注了土壤动物肠道微生物的生态学功能,总体上体现在肠道微生物能帮助宿主分解食物基质、参与营养利用、影响寿命和繁殖及提高宿主免疫能力,且其能够影响土壤动物的气体排放及介导其对生态系... 相似文献
8.
Boron (B) is a naturally occurring element that is found in the form of borates in the oceans, sedimentary rocks, coal, shale,
and in some soils. Borates are released naturally into the atmosphere and aquatic environment from oceans, geothermal steams,
and weathering of clay-rich sedimentary rocks. B is also released to a lesser extent from anthropogenic sources. B concentrations
in air range from <0.5 to 80 ng/m 3 with an average of 20 ng/m 3, and in soils from 10 to 300 mg/kg with an average of 30 mg/kg. Concentrations of B in surface freshwaters are typically
< 0.1–0.5 mg/L; much higher concentrations are measured in a few areas, depending on the geochemical nature of the drainage
catchment. B accumulates in both aquatic and terrestrial plants, but it does not appear to be biomagnified through the food
chain.
No observed effect concentrations (NOECs) for aquatic invertebrates tend to be in the range of 6–10 mg B/L with lower values
of 1–2 mg/L for community studies. No effect concentrations for fish in natural waters are around 1 mg/L, although lower values
have been recorded in reconstituted water. Comparing no effect concentrations with the general ambient environmental levels
indicates that the risk to aquatic ecosystems from B is low. In a few B-rich areas, natural levels will be higher; however,
there is some indication that organisms may be Actapted to the local conditions.
B is an essential micronutrient for higher plants with interspecies differences in the levels required for optimum growth.
In general, there is a small concentration range between deficiency and toxicity; however, toxicity owing to excess B is much
less common in the environment than B deficiency. Levels of B in aquatic plants growing in areas receiving B-rich runoff from
irrigated fields are higher than dietary concentrations, which cause effects on the growth of young birds in the laboratory;
however, the bioavailability in the field of such plant-accumulated B is uncertain. 相似文献
10.
Global pharmaceutical consumption is rising with the growing and ageing human population and more intensive food production. Recent studies have revealed pharmaceutical residues in a wide range of ecosystems and organisms. Environmental concentrations are often low, but pharmaceuticals typically are designed to have biological effects at low doses, acting on physiological systems that can be evolutionarily conserved across taxa. This Theme Issue introduces the latest research investigating the risks of environmentally relevant concentrations of pharmaceuticals to vertebrate wildlife. We take a holistic, global view of environmental exposure to pharmaceuticals encompassing terrestrial, freshwater and marine ecosystems in high- and low-income countries. Based on both field and laboratory data, the evidence for and relevance of changes to physiology and behaviour, in addition to mortality and reproductive effects, are examined in terms of the population- and community-level consequences of pharmaceutical exposure on wildlife. Studies on uptake, trophic transfer and indirect effects of pharmaceuticals acting via food webs are presented. Given the logistical and ethical complexities of research in this area, several papers focus on techniques for prioritizing which compounds are most likely to harm wildlife and how modelling approaches can make predictions about the bioavailability, metabolism and toxicity of pharmaceuticals in non-target species. This Theme Issue aims to help clarify the uncertainties, highlight opportunities and inform ongoing scientific and policy debates on the impacts of pharmaceuticals in the environment. 相似文献
11.
In December 2015, the Johns Hopkins Bloomberg School of Public Health held the first-ever summit on the intersection between nonhuman animal ethics and human health. The conference covered a variety of issues where animal health intersects with human health, including the wildlife trade, animal agriculture, and animal experimentation. This article provides a brief overview and critique of the summit. 相似文献
13.
Any experiment involving living organisms requires justification of the need and moral defensibleness of the study. Statistical planning, design, and sample size calculation of the experiment are no less important review criteria than general medical and ethical points to consider. Errors made in the statistical planning and data evaluation phase can have severe consequences on both results and conclusions. They might proliferate and thus impact future trials—an unintended outcome of fundamental research with profound ethical consequences. Unified statistical standards are currently missing for animal review boards in Germany. In order to accompany, we developed a biometric form to be filled and handed in with the proposal at the concerned local authority on animal welfare. It addresses relevant points to consider for biostatistical planning of animal experiments and can help both the applicants and the reviewers in overseeing the entire experiment(s) planned. Furthermore, the form might also aid in meeting the current standards set by the 3+3R's principle of animal experimentation: Replacement, Reduction, Refinement as well as Robustness, Registration, and Reporting. The form has already been in use by the concerned local authority of animal welfare in Berlin, Germany. In addition, we provide reference to our user guide giving more detailed explanation and examples for each section of the biometric form. Unifying the set of biostatistical aspects will help both the applicants and the reviewers to equal standards and increase quality of preclinical research projects, also for translational, multicenter, or international studies. 相似文献
14.
Microorganisms in nature are largely responsible for the biodegradation and removal of toxic and non-toxic chemicals. Many organisms are also known to have specific ecological niches for proliferation and colonization. The nature of the environment dictates to a large extent the biodegradability of synthetic compounds by modulating the evolutionary processes in microorganisms for new degradative genes. Similarly, environmental factors often determine the extent of microbial gene expression by activating or repressing specific gene or sets of genes through a sensory signal transduction process. Understanding how the environment modulates microbial activity is critical for successful bioremediative applications. 相似文献
15.
病毒对珊瑚礁生态系统中的生物进化、生物地球化学循环、珊瑚疾病等方面具有重要的生态影响。随着珊瑚礁的全球性退化,病毒在珊瑚礁生态系统中的功能与危害日益显现。综述了珊瑚礁生态系统中病毒的研究现状与进展,包括:(1)珊瑚礁病毒的多样性与分布特征(水体、宿主、核心病毒组);(2)珊瑚礁病毒的生态功能(感染方式、促进生物进化、生物地球化学循环);(3)珊瑚礁病毒对全球气候变化的响应(热压力、珊瑚疾病)。总体而言,珊瑚礁生态系统具有极高的病毒多样性,所发现的60个科占已知所有病毒科数量的58%。珊瑚的核心病毒组主要由双链DNA病毒、单链DNA病毒、单链逆转录病毒所组成,珊瑚黏液层对病毒具有富集作用。"Piggyback-the-Winner"(依附-胜利)是病毒在珊瑚礁中主要的生物动力学模式,其可通过水平基因迁移的方式促进礁区生物进化。病毒可通过裂解细菌与浮游藻类的途径参与珊瑚礁的生物地球化学循环,尤其是碳循环与氮循环过程。此外,病毒还具有介导珊瑚热白化与直接引发珊瑚疾病的能力,这会影响珊瑚礁生态系统应对气候变化的适应性与恢复力。基于国际上的研究进展综述,结合南海珊瑚礁生态现状提出以下研究方向,以期促进我国珊瑚礁病毒学的发展:(1)开展南海珊瑚礁中病毒多样性的识别及其时-空分布特征研究;(2)探索病毒对南海珊瑚热白化、珊瑚疾病的介导作用及其与气候变化的关系;(3)揭示病毒对南海珊瑚礁生物地球化学循环的贡献。 相似文献
16.
The contribution of healthcare ethics committee (HEC) members to HECs is fundamental. However, little is known about how HEC
members view clinical ethics. We report results from a qualitative study of the moral psychology of HEC members. We found
that contrary to the existing Kohlberg-based studies, HEC members hold a pragmatic non-expert view of clinical ethics based
mainly on respect for persons and a commitment to the patient’s good. In general, HEC members hold deflationary views regarding
moral theory. Ethical principles are not abstract foundations but the expression of moral commitments to patients that pre-exist
awareness of moral theory. Emotions and proximity to patient sufferance fundamentally shape the views of HEC members on clinical
ethics. Further work at the intersection of clinical ethics and qualitative research could bring to the foreground lay perspectives
on moral problems that may differ from bioethics expert views. 相似文献
17.
Isotopic and nuclear techniques play an important role in food and agriculture, health and industry. This paper discusses the use of these techniques and highlights potential for their use in the area of Animal Production. These techniques are discussed in two parts: (1) Isotopic methods and (2) non-isotopic nuclear methods. The isotopic techniques discussed are: stable- ( 15N) and radio-isotope ( 35S or 32P) incorporation methods for measuring microbial mass in vitro and in vivo; 125I-labelled bovine serum albumin and 14C-labelled polyethylene glycol assays for measuring tannin in feeds; a method based on the feeding of isotope-labelled protein ( 15N or 125I) complexed with tannin for ranking different tannins for their abilities to release protein for digestion in vivo; 14C-uric acid and 14C-allantoin infusion methods for development of models describing excretion of purine derivatives in urine and microbial protein supply to ruminants, which permit assessment of nutritional status of animals and determination of nutritional quality of feed resources; a 15N isotope dilution technique using 15N-leucine to distinguish feed and endogenous secretions at the ileum, for determination of true digestibility of protein-rich tree leaves and aquatic plants in pigs; progesterone radioimmunoassay (RIA) for enhancing reproductive efficiency of ruminants, and RIA based leptin and insulin like growth factor assays for assessing the nutritional status of animals; feeding of 15N enriched plant material to generate 15N-labelled excreta for research on the fate of excreta N in the environment; 15N, 13C and 34S isotopic methods for nutrient budgeting and for following the nutrient pathways in the soil–plant–animal continuum; 32P- or 33P-labelled fertilizers for estimating the efficiency of P utilization in legume leaf production used for livestock feeding; double labelled water ( 18O and 2H labelled) method for estimating energy expenditures of grazing animals, body composition, basal metabolic rate, and milk output in cows with calves; NaH 13CO 3/NaH 14CO 3 infusion for estimation of the carbon dioxide production, which in turn is used to estimate energy expenditure in free-ranging animals; 3H- or 14C-labelled methane and 14C-labelled volatile fatty acids dilution technique for direct and indirect (using stoichiometry of carbohydrate fermentation) for determination of methane emission from livestock; 15N dilution technique requiring labeling the soil with 15N fertilizer ( 15N-ammonium sulphate or 15N-urea) for estimation of nitrogen fixation by leguminous trees and pastures. The non-isotopic nuclear techniques that have been used or have the potential for use are: dual energy X-ray absorptionmetry and computer tomography for body composition determination; nuclear magnetic resonance techniques, fast atom bombardment mass spectroscopy, and mass ionisation spectroscopy for identification and structure determination of bioactive moieties of plant origin having potential for rumen manipulation or controlling internal parasites; gamma irradiation for inactivating antinutrients such as protease inhibitors, lectin, phytic acid, non-starch polysaccharides and oligosaccharides in feeds; induced mutations with gamma radiation, electron beam and fast neutrons for producing useful mutants of forage plants with improved yield, nutrient profiles and uptake. 相似文献
18.
Ethics tells us: do good and do no harm and invokes the norms of justice, equity and respect for autonomy in protecting and promoting health and well-being. The Precautionary Principle, a contemporary re-definition of Bradford Hill's case for action, gives us a common sense rule for doing good by preventing harm to public health from delay: when in doubt about the presence of a hazard, there should be no doubt about its prevention or removal. It shifts the burden of proof from showing presence of risk to showing absence of risk, aims to do good by preventing harm, and subsumes the upstream strategies of the DPSEEA (Driving Forces Pressure Stress Exposure Effect Action) model and downstream strategies from molecular epidemiology for detection and prevention of risk. The Precautionary Principle has emerged because of the ethical import of delays in detection of risks to human health and the environment. Ethical principles, the Precautionary Principle, the DPSEEA model and molecular epidemiology all imply re-emphasizing epidemiology's classic rôle for early detection and prevention. Delays in recognizing risks from past exposures and acting on the findings (e.g., cigarette smoking and lung cancer, asbestos, organochlorines and endocrine disruption, radiofrequency, raised travel speeds) were examples of failures that were not only scientific, but ethical, since they resulted in preventable harm to exposed populations. These may delay results from, among other things, external and internal determinants of epidemiologic investigations of hazard and risk, including misuse of tests of statistical significance. Furthermore, applying the Precautionary Principle to ensure justice, equity, and respect for autonomy raises questions concerning the short-term costs of implementation to achieve long-term goals and the principles that guide compensation. 相似文献
19.
The indigenous terrestrial planarian fauna (three species) of the UK is outnumbered by introduced exotics, of which there are at least nine species. The New Zealand flatworm, Arthurdendyus triangularis, is one of the most widespread and apparent of these non-indigenous earthworm predators, particularly in Northern Ireland and central Scotland. Despite its having been in the UK for at least 35 yr, our knowledge of the biology and ecology of this species remains somewhat limited. In Scotland, A. triangularis occurs predominantly in botanical and domestic gardens, and is not generally considered to be a problem on agricultural land. The situation in Northern Ireland is different; although predominantly found in domestic gardens, it appears to have colonised grass leys many localities although the impact on earthworm populations remains ambiguous. In England, records are increasing, predominantly from northern regions. Studies have indicated that earthworm species vary in terms of their vulnerability to predation by A. triangularis; surface-active and anecic species are considered to be most at risk. However, A. triangulatus and earthworm populations are known to coexist, apparently in a state of dynamic equilibrium, in a number of localities. Naturally-occurring planarian populations are often severely constrained by food supply, but individuals survive lengthy periods of starvation. Such behaviour may preclude the natural recolonisation of habitats by prey species. Very much higher rates of population growth can be achieved where food is not limited, and where favourable conditions result from horticultural practices. The mobility of the prey species may determine the dispersal strategy of the flatworm predator, and a propensity not to move away from centres of prey density might account for the relatively low rate of colonisation of agricultural land by A. triangulatus. Additionally, reliance on protected refuges, may explain the present, somewhat limited distribution in the UK, particularly in southern England. It is difficult to estimate the potential distribution of A. triangulatus, because of the lack of fundamental knowledge of its ecoclimatic requirements. A better understanding is needed of the precise habitat requirements (and constraints) of A. triangulatus, particularly where this species appears to have adapted to rural conditions. 相似文献
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