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1.
Humans feel uncertain. They know when they do not know. These feelings and the responses to them ground the research literature on metacognition. It is a natural question whether animals share this cognitive capacity, and thus animal metacognition has become an influential research area within comparative psychology. Researchers have explored this question by testing many species using perception and memory paradigms. There is an emerging consensus that animals share functional parallels with humans' conscious metacognition. Of course, this research area poses difficult issues of scientific inference. How firmly should we hold the line in insisting that animals' performances are low-level and associative? How high should we set the bar for concluding that animals share metacognitive capacities with humans? This area offers a constructive case study for considering theoretical problems that often confront comparative psychologists. The authors present this case study and address diverse issues of scientific judgement and interpretation within comparative psychology.  相似文献   

2.
Violence between and among Christians and Muslims of the southwestern Philippines provides the ethnographic setting for an investigation of Herzfeld's paradox of social indifference. But there is yet another paradox in this case: Why has this 400-year conflict been characterized by a proliferation of contested identities among the insurgents, those who most need to be united?
Is this another case of the force of "hegemony," with the oppressed somehow duped into practices detrimental to their own interests? But how? And by what agency? The Philippine case reveals the challenging complexities of identity construction to be faced in any attempt to reach an understanding of these issues.  相似文献   

3.
The scientific study of protein surfactant interactions goes back more than a century, and has been put to practical uses in everything from the estimation of protein molecular weights to efficient washing powder enzymes and products for personal hygiene. After a burst of activity in the late 1960s and early 1970s that established the general principles of how charged surfactants bind to and denature proteins, the field has kept a relatively low profile until the last decade. Within this period there has been a maturation of techniques for more accurate and sophisticated analyses of protein-surfactant complexes such as calorimetry and small angle scattering techniques. In this review I provide an overview of different useful approaches to study these complexes and identify eight different issues which define central concepts in the field. (1) Are proteins denatured by monomeric surfactant molecules, micelles or both? (2) How does unfolding of proteins in surfactant compare with "proper" unfolding in chemical denaturants? Recent work has highlighted the role of shared micelles, rather than monomers, below the critical micelle concentration (cmc) in promoting both protein denaturation and formation of higher order structures. Kinetic studies have extended the experimentally accessible range of surfactant concentrations to far above the cmc, revealing numerous different modes of denaturation by ionic surfactants below and above the cmc which reflect micellar properties as much as protein unfolding pathways. Uncharged surfactants follow a completely different denaturation strategy involving synergy between monomers and micelles. The high affinity of charged surfactants for proteins means that unfolding pathways are generally different in surfactants versus chemical denaturants, although there are common traits. Other issues are as follows: (3) Are there non-denaturing roles for SDS? (4) How reversible is unfolding in SDS? (5) How do solvent conditions affect the way in which surfactants denature proteins? The last three issues compare SDS with "proper" membranes. (6) Do anionic surfactants such as SDS mimic biological membranes? (7) How do mixed micelles interact with globular proteins? (8) How can mixed micelles be used to measure the stability of membrane proteins? The growing efforts to understand the unique features of membrane proteins have encouraged the development of mixed micelles to study the equilibria and kinetics of this class of proteins, and traits which unite globular and membrane proteins have also emerged. These issues emphasise the amazing power of surfactants to both extend the protein conformational landscape and at the same time provide convenient and reversible short-cuts between the native and denatured state for otherwise obdurate membrane proteins.  相似文献   

4.
DeGrazia D 《Bioethics》1995,9(1):50-61
The idea of a patient's best interests raises issues in prudential value theory–the study of what makes up an individual's ultimate (nonmoral) good or well-being. While this connection may strike a philosopher as obvious, the literature on the best interests standard reveals almost no engagement of recent work in value theory. There seems to be a growing sentiment among bioethicists that their work is independent of philosophical theorizing. Is this sentiment wrong in the present case? Does value theory make a significant difference in interpreting best interests? In pursuing this question, I begin with a quick sketch of broad kinds of value theories, identifying representatives that are plausible enough to count as contenders. I then explore what each account suggests in (1) neonatal treatment decisions, and (2) decisions for patients in persistent vegetative states. I conclude that while these accounts converge somewhat in their interpretations of best interests, they also have importantly different implications.  相似文献   

5.
To what extent is truth required for reconciliation of peoples in conflict? What kind of truth? Objective truth, subjective truth? Maybe reconciliation require that the pursuit of truth be limited? The trial of the former “Khmer Rouge” leaders in Cambodia for crimes against humanity provides a case where these issues are examined.  相似文献   

6.
石制品微痕是进行石器功能研究、了解史前人类行为模式的重要考古证据之一。本文在以往实验研究的基础上, 设计并开展多阶段燧石制品"刮骨"微痕实验, 分阶段详细、直观地记录石制品刃缘使用微痕的最初形成与发展动态。实验研究表明, "刮骨"使用微痕迹随着使用时间长度的递增发生复杂的动态变化, 使用微痕的发展与使用时间之间并非简单的正函数关系。片疤破损自开始在一定时间段内呈连续发生状态, 随后停止发展, 是确认石制品是否经过使用的良好指示。磨圆表现出由少到多、由弱及强的逐渐发育过程, 可以反映石制品的使用时间和强度, 也是判断使用微痕的重要参考依据。  相似文献   

7.
Practitioners of life cycle assessment (LCA) have recently turned their attention to social issues in the supply chain. The United Nations life cycle initiative's social LCA task force has completed its guidelines for social life cycle assessment of products, and awareness of managing upstream corporate social responsibility (CSR) issues has risen due to the growing popularity of LCA. This article explores one approach to assessing social issues in the supply chain—life cycle attribute assessment (LCAA). The approach was originally proposed by Gregory Norris in 2006, and we present here a case study. LCAA builds on the theoretical structure of environmental LCA to construct a supply chain model. Instead of calculating quantitative impacts, however, it asks the question “What percentage of my supply chain has attribute X?” X may represent a certification from a CSR body or a self‐defined attribute, such as “is locally produced.” We believe LCAA may serve as an aid to discussions of how current and popular CSR indicators may be integrated into a supply chain model. The case study demonstrates the structure of LCAA, which is very similar to that of traditional environmental LCA. A labor hours data set was developed as a satellite matrix to determine number of worker hours in a greenhouse tomato supply. Data from the Quebec tomato producer were used to analyze how the company performed on eight sample LCAA indicators, and conclusions were drawn about where the company should focus CSR efforts.  相似文献   

8.
9.
Legal aspects of genetic information   总被引:4,自引:0,他引:4  
The federally funded Human Genome Initiative will lead to the development of new capabilities to learn about an individual''s genetic status. Legal issues are raised concerning patients'' and other parties'' access to that information. This article discusses the effect of existing statutes and case law on three pivotal questions: To what sort of information are people entitled? What control should people have over their genetic information? Do people have a right to refuse genetic information? The article emphasizes that the law protects a patient''s right to obtain or refuse genetic information about oneself, as well as the right to control the dissemination of that information to others.  相似文献   

10.
Häyry H 《Bioethics》1997,11(3-4):271-276
In different countries responses to important bioethical issues are different, as exemplified by the attitudes towards the voluntary and active forms of medical euthanasia. But why is this the case? My suggestion is that the roots of the variety are, to be considerable degree, ideological. The most important present-day political ideologies all have their roots in the prevailing doctrines of moral and social philosophy. In the paper these doctrines are outlined and the predicted response towards active voluntary euthanasia within each model is sketched. The conclusion reached is that while it would in some countries be dangerous to allow euthanasia in the prevailing circumstances, the solution is not to hinder the legalization process but to alter the circumstances.  相似文献   

11.
Heta Häyry 《Bioethics》1997,11(3&4):271-276
In different countries responses to important bioethical issues are different, as exemplified by the attitudes towards the voluntary and active forms of medical euthanasia. But why is this the case? My suggestion is that the roots of the variety are, to a considerable degree, ideological.
The most important present-day political ideologies all have their roots in the prevailing doctrines of moral and social philosophy. In the paper these doctrines are outlined and the predicted response towards active voluntary euthanasia within each model is sketched. The conclusion reached is that while it would in some countries be dangerous to allow euthanasia in the prevailing circumstances, the solution is not to hinder the legalization process but to alter the circumstances.  相似文献   

12.
The centrality of emotion in thought and action is increasingly recognized in the human sciences, though basic questions of definition and scope remain unresolved. Where do emotions begin and end? How should we identify and analyse them? How should we write about them? Ethnographic fieldwork, as pioneered by Malinowski, offers powerful insights into the place of emotion in social life; but emotions are peculiarly difficult to capture in the generalizing format of case study and ethnographic summary. In this article I argue that semantic, structural, and discourse‐based approaches tend to miss what is most important – what counts for the persons concerned and therefore what makes the emotion. I review the conceptual and methodological issues and conclude that only a narrative approach can capture both the particularity and the temporal dimension of emotion, restoring verisimilitude and fidelity to experience.  相似文献   

13.
The aim of this study was to investigate the performance of a newly devised high-performance thin-layer chromatography (HPTLC) method in quantifying common liposome membrane components, including the five phospholipids (PLs), phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, as well as cholesterol, cholesteryl hemisuccinate, and linoleic acid. Besides strictly keeping to a standardized procedure, three parameters were particularly critical for proper quantification. First, a relative humidity of higher than 60% caused migration distances to increase and reduced the resolution of the PLs on a silica-gel 60 HPTLC plate. Second, PLs underwent oxidative combustion during storage for 2 or 24 hours on an HPTLC plate, with peak losses of up to 25–44%. These losses could be prevented by storage under nitrogen and, to some extent, by the addition of the antioxidant, DL-α-tocopherol. Third, even with automated sample application, the accuracy and consistency of the application volume proved to be an important cause of error and needs routine verification. Considering these parameters, the method was found to accurately and precisely determine the composition of three different liposome preparations. The recovery was 97.2–101.8%, compared to secondary methods, and consistent over different days and with different operators (mean RSD of the recovery: 2.03?±?1.16%, n?=?9). The working range was determined to be 100–300?ng in the case of the PLs (individual limit of determination between 40 and 80?ng) and 20–60?ng in the case of cholesterol (limit of determination: 16?ng).  相似文献   

14.
Recent advances in statistical software have led to the rapid diffusion of new methods for modelling longitudinal data. Multilevel (also known as hierarchical or random effects) models for binary outcomes have generally been based on a logistic-normal specification, by analogy with earlier work for normally distributed data. The appropriate application and interpretation of these models remains somewhat unclear, especially when compared with the computationally more straightforward semiparametric or 'marginal' modelling (GEE) approaches. In this paper we pose two interrelated questions. First, what limits should be placed on the interpretation of the coefficients and inferences derived from random-effect models involving binary outcomes? Second, what diagnostic checks are appropriate for evaluating whether such random-effect models provide adequate fits to the data? We address these questions by means of an extended case study using data on adolescent smoking from a large cohort study. Bayesian estimation methods are used to fit a discrete-mixture alternative to the standard logistic-normal model, and posterior predictive checking is used to assess model fit. Surprising parallels in the parameter estimates from the logistic-normal and mixture models are described and used to question the interpretability of the so-called 'subject-specific' regression coefficients from the standard multilevel approach. Posterior predictive checks suggest a serious lack of fit of both multilevel models. The results do not provide final answers to the two questions posed, but we expect that lessons learned from the case study will provide general guidance for further investigation of these important issues.  相似文献   

15.
Social and economic policy issues relevant to marine aquaculture   总被引:1,自引:0,他引:1  
This paper presents a critical review of current social, economic and policy issues relevant to marine aquaculture (mariculture) in Europe. Tools for identifying the full range of social, economic and environmental issues that influence the sustainable development of mariculture are examined. Under present sectoral approaches to policy, investment, development planning and natural resources management, these issues continue to be treated in isolation. The four main challenges presented in this paper are: (i) how to create a more objective information base with which to assess the social, economic and environmental factors that condition the sustainability of mariculture; (ii) how to provide information from different disciplines in an easy to obtain and compatible format; (iii) how to better integrate knowledge and skills from different disciplines to create a holistic and robust framework for assessing options for mariculture development that integrates social, economic and environmental parameters; and (iv) the effective integration of these assessments into the formulation of policy, investment strategies, spatial plans and natural resources management for coastal areas. Specific issues that need to be addressed within the framework for the integrated evaluation of the economic, social and environmental parameters governing the sustainable development of mariculture include: ? development of more accurate information on the economic, social and environmental benefits and costs of well‐planned and managed mariculture; ? clearer definition of gaps in existing knowledge on factors critical to the sustainable and equitable development of mariculture; ? development of pro‐active consideration of the coastal land and water resource requirements of mariculture as part of strategic economic planning, spatial planning and natural resources management; ? the need for more equitable treatment of mariculture regarding rights of access to sites for development and use of resources; ? development of awareness among decision‐makers, planners, and managers from different sectoral agencies of the contribution that mariculture may make in promoting the sustainable use of coastal ecosystems; ? promotion of a shift in emphasis away from controlling the end use of resources and toward a more balanced approach to coastal development where emphasis is also given to maintaining the health and productivity of coastal ecosystems and the resources they generate that sustain different forms of activity, including mariculture.  相似文献   

16.
Halliday  Gordon 《Dreaming》2004,14(1):30
Do juvenile felons suffer nightmares? Can dreamwork be useful with this population? After a review of the generally older and limited literature on these issues, 2 new surveys and several case examples give positive answers to these questions. In Study 1, 50 of 100 adolescent male felons reported dreams and 12 reported nightmares. In Study 2, with the addition of a follow-up prompt, 73 of 100 adolescent male felons reported dreams within the prior month and 13 reported nightmares. Seven case examples illustrate verbal interventions for nightmares, and 5 case examples illustrate benefits youths could derive from dreamwork. Suggestions for further research are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
The consumption of low-salt bread represents an efficient way to improve public health by decreasing cardiovascular health issues related to increased intakes of sodium chloride (NaCl). The reduction of NaCl influences the bread quality characteristics, in particular the shelf-life. Calcium propionate (CP) is commonly used in bread as an antifungal agent. Alternatively, sourdough can be used as a natural preservative. This work addresses the feasibility of NaCl reduction in wheat bread focussing on shelf-life and the compensation using sourdough as well as chemical preservatives. The impact of NaCl reduction and the addition of preservative agents in conjunction with different NaCl concentrations on the shelf-life of bread were tested under 'environmental' conditions in a bakery as well as using challenge tests against selected fungi. The challenge tests were performed using fungi commonly found in the bakery environment such as Penicillium expansum, Fusarium culmorum and Aspergillus niger. NaCl reduction decreased the shelf-life by 1-2?days. The addition of sourdough with antifungal activity prolonged the shelf-life to 12-14?days whereas the addition of 0.3?% calcium propionate prolonged the shelf-life to 10-12?days only. The fungal challenge tests revealed differences in the determined shelf-life between the different fungi based on their resistance. Similar antifungal performance was observed in sourdough breads and calcium propionate breads when tested against the different indicator moulds. The findings of this study indicate that addition of sourdough fermented using a specifically selected antifungal Lactobacillus amylovorus DSM 19280 can replace the chemical preservative calcium propionate addition and compensate for the reduced level and, therefore, guarantee the product safety of low-salt bread.  相似文献   

18.
Andrews N 《Biologicals》2012,40(5):389-392
Three commonly used designs for vaccine safety assessment post licensure are cohort, case-control and self-controlled case series. These methods are often used with routine health databases and immunisation registries. This paper considers the issues that may arise when designing an epidemiological study, such as understanding the vaccine safety question, case definition and finding, limitations of data sources, uncontrolled confounding, and pitfalls that apply to the individual designs. The example of MMR and autism, where all three designs have been used, is presented to help consider these issues.  相似文献   

19.
Pollen mediated gene flow is the most widely debated biosafety issue in case of genetically modified crop plants and is a primary determining factor for permitting their field release, particularly major food crops like rice. The alleged consequences of gene escape into wild/weedy relatives that coexist together with cultivated forms in rice fields in several countries is perceived to be a major concern. In an effort to estimate the gene flow in rice in a tropical environment, rice varieties stacked with three bacterial blight (BB) resistance alleles and a cytoplasmic male sterile (CMS) line were used as donors and receiver of pollen respectively and the pollen flow was tracked with molecular markers that are closely linked to BB resistance genes. The study could detect gene flow up to 20?m distance with environmental factors like temperature and humidity influencing it. The gene flow observed at longer distances than the 10?m distance suggested earlier advocate caution and suggests that all the relevant biosafety issues need to be addressed prior to release of GM rice in tropical countries where sympatric association of wild relatives with cultivated rice with frequent crop-weedy gene flow both ways is quite common.  相似文献   

20.
The tumor vasculature is an increasingly attractive target for development of anticancer drugs. The fundamental principle for antiangiogenic cancer therapy is based on the inhibitory effect of chemical compounds, proteins or nucleotides on tumor angiogenesis. Indeed, in almost all preclinical tumor models, antiangiogenic monotherapy with different agents shows potent effects on suppression of tumor growth. However, antiangiogenic monotherapy has barely produced any clinical benefits in cancer patients. Although in combination with chemotherapy some antiangiogenic drugs demonstrate survival improvement in patients with certain types of cancers, the overall benefits by addition of antiangiogenic drugs (ADs) to chemotherapy remain modest. The disparity of AD responses between preclinical models and clinical cancer patients has raised important issues, which include: 1) Are current animal tumor models appropriate for assessing the therapeutic efficacy of ADs for clinical development? 2) What are the key differences between mouse tumor models and human cancer patients? 3) Are anti-VEGF drugs off target in cancer patients? 4) What are alternative options for improvement of the clinical benefits of ADs? In this short review, I discuss these critical issues in relation to the clinical practice of ADs.  相似文献   

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