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1.
OBJECTIVE: To study the extent to which general practitioners'' questioning behaviour in routine practice is likely to encourage the adoption of evidence based medicine. DESIGN: Self recording of questions by doctors during consultations immediately followed by semistructured interview. SETTING: Urban Australian general practice. SUBJECTS: Random sample of 27 general practitioners followed over a half day of consultations. MAIN OUTCOME MEASURES: Rate of recording of clinical questions about patients'' care which doctors would like answered; frequency with which doctors found answers to their questions. RESULTS: Doctors asked a total of 85 clinical questions, at a rate of 2.4 for every 10 patients seen. They found satisfactory answers to 67 (79%) of these questions. Doctors who worked in small practices (of one or two doctors) had a significantly lower rate of questioning than did those in larger practices (1.6 questions per 10 patients v 3.0 patients, P = 0.049). No other factors were significantly related to rate of questioning. CONCLUSIONS: These results do not support the view that doctors routinely generate a large number of unanswered clinical questions. It may be necessary to promote questioning behaviour in routine practice if evidence based medicine and other forms of self directed learning are to be successfully introduced.  相似文献   

2.
The complexity of nervous systems alters the evolvability of behaviour. Complex nervous systems are phylogenetically constrained; nevertheless particular species-specific behaviours have repeatedly evolved, suggesting a predisposition towards those behaviours. Independently evolved behaviours in animals that share a common neural architecture are generally produced by homologous neural structures, homologous neural pathways and even in the case of some invertebrates, homologous identified neurons. Such parallel evolution has been documented in the chromatic sensitivity of visual systems, motor behaviours and complex social behaviours such as pair-bonding. The appearance of homoplasious behaviours produced by homologous neural substrates suggests that there might be features of these nervous systems that favoured the repeated evolution of particular behaviours. Neuromodulation may be one such feature because it allows anatomically defined neural circuitry to be re-purposed. The developmental, genetic and physiological mechanisms that contribute to nervous system complexity may also bias the evolution of behaviour, thereby affecting the evolvability of species-specific behaviour.  相似文献   

3.
Scenario analysis (SA) is the process of developing plausible futures around the forces affecting an organization in the face of uncertainties over which it has little control. SA is widely used in the private sector and increasingly a tool of environmental planners grappling with problems of great complexity and uncertainty. SA ideally marries expert judgment with the broader perspectives engaged stakeholders bring. While the 1990 Oil Pollution Act (OPA) brought substantive improvement to oil spill contingency planning, many issues remain. Reguatorily prescribed definitions of ‘worst case’ lead to SA practice that seldom achieves the full promise of the SA approach. Contingency planning overly focused on tactical and operational considerations can leave response managers little prepared to deal with public concerns that emerge in the event of a major spill, concerns increasingly magnified through social media. Politics continues to contribute to poorly conceived contingency planning in which adopted scenarios bear little resemblance to events that subsequently transpire. Risk attenuation and risk amplification both inhibit scenario-based planning around oil spills, evinced by the Deepwater Horizon spill. Improvements in pre-planning in the aftermath of the Exxon Valdez oil spill nevertheless provide a foundation for more effective use of SA.  相似文献   

4.
The processes for making decisions on objectives and management actions were identified in nine easily available management planning guides, all aimed at UK protected sites (Sites of Special Scientific Interest, Natura 2000, Ramsar, etc), and compared. They varied considerably between guides, to the extent that no two guides recommend identical processes. Processes were sometimes entirely absent, and usually incomplete. Poor guidance on decision-making may result in plans that are ineffective or damaging to the conservation of sites. The reasons for inconsistency are explored, suggestions are made for improving and testing of management planning guidance, and questions are raised about best practice and the value of a standard approach in planning the management of sites.  相似文献   

5.
Virtually all Western countries are seeking to bring retirement ages more in line with increases in longevity. The central question in this paper is whether individuals choose a retirement age that fits their life expectancy. This would be ideal from a public policy perspective. The present study aims to test empirically whether retirement planning varies with expectations of survival among a sample of older employees in the Netherlands. Two questions are addressed: (1) What are older employees' expectations of their remaining lifetime, and what factors influence this subjective life expectancy? (2) Are individuals who perceive longer life horizons (high subjective life expectancy) more inclined to retire later than people who expect to live shorter? Using data from a panel study on retirement behaviour in the Netherlands (N=1621 older employees aged 50-60), regression and survival models are estimated to examine the effect of subjective life expectancy on retirement planning and behaviour. The results indicate that subjective life expectancy is a factor that is taken into account in retirement decision making, at least as far as retirement intentions are concerned. Older employees with longer time horizons have a preference for later retirement. When it comes to actual behaviour, however, time horizon does not appear to play a role. The results suggest that particularly employees with a high perceived life expectancy and an intention to work longer do not succeed in carrying their intentions into effect.  相似文献   

6.
Predictive models of soil and plant processes should be of much benefit both in developing and developed countries. They can assist in enabling agronomic practices to be better adjusted for differences in conditions; in avoiding disasters that can accompany change in land use; in minimizing waste and environmental pollution, and in modifying and implementing legislation. These views are discussed in the light of recent advances. Particular attention is drawn to (i) the excellent relationships linking average national yields, nutrient uptakes, etc. to single factors such as average fertilizer application; (ii) equations for predicting the behaviour of added chemicals and water in soil that have been obtained by rigorous deduction from physical and chemical laws; (iii) the discovery of semi-empirical, but nevertheless widely applicable quantitative relations for key soil and plant processes, and (iv) the formulation and use of computer models for field situations. There is a pressing need to find ways of presenting the outcome of this work so that it can be more widely applied in practice.  相似文献   

7.
Although a variety of basic insect behaviours have inspired successful robot implementations, more complex capabilities in these 'simple' animals are often overlooked. By reviewing the general architecture of their nervous systems, we gain insight into how they are able to integrate behaviours, perform pattern recognition, context-dependent learning, and combine many sensory inputs in tasks such as navigation. We review in particular what is known about two specific 'higher' areas in the insect brain, the mushroom bodies and the central complex, and how they are involved in controlling an insect's behaviour. While much of the functional interpretation of this information is still speculative, it nevertheless suggests some promising new approaches to obtaining adaptive behaviour in robots.  相似文献   

8.
Existing compartmental mathematical modelling methods for epidemics, such as SEIR models, cannot accurately represent effects of contact tracing. This makes them inappropriate for evaluating testing and contact tracing strategies to contain an outbreak. An alternative used in practice is the application of agent- or individual-based models (ABM). However ABMs are complex, less well-understood and much more computationally expensive. This paper presents a new method for accurately including the effects of Testing, contact-Tracing and Isolation (TTI) strategies in standard compartmental models. We derive our method using a careful probabilistic argument to show how contact tracing at the individual level is reflected in aggregate on the population level. We show that the resultant SEIR-TTI model accurately approximates the behaviour of a mechanistic agent-based model at far less computational cost. The computational efficiency is such that it can be easily and cheaply used for exploratory modelling to quantify the required levels of testing and tracing, alone and with other interventions, to assist adaptive planning for managing disease outbreaks.  相似文献   

9.
10.
Ferraz et al . (2008) indicated the need for planning in biological monitoring in the Amazon, and reviewed what they considered recent progress. The problems and solutions they discuss are well known, and it is unlikely that many biologists would disagree with most of them. However, the authors do not indicate that most of these issues are already being addressed in practice in the Amazon, especially by the Programa de Pesquisas em Biodiversidade (PPBio) of the Brazilian Ministry of Science and Technology. The only major issue about which we do not agree with Ferraz et al . (2008) relates to the design of monitoring programs. The authors recommended tailoring experimental designs to specific threats, which will result in a multitude of idiosyncratic designs and incompatible data sets. We suggest that generic broad-scale designs will allow us to answer more questions with greater confidence, because the investment in each location provides information about regional and global questions. Although specific designs may be more effective in some cases, there are insufficient resources available to install different research infrastructure for every possible threat.  相似文献   

11.
Pharmacogenomics is the study of the myriad interactions between genes and pharmacotherapy. Developments in pharmacogenomics have changed and will affect pharmaceutical research, drug development and the practice of medicine in a significant way. In this article, we make an inventory of the ethical implications that might arise as a result of possible developments in pharmacogenomics and investigate whether the present ethical framework will be able to adequately answer arising questions. We think that many of the questions related to the consequences of pharmacogenomics are answerable along the lines of present ethical thinking. We also believe, however, that many 'changes of degree' may result in a 'change of kind.' We therefore think that pharmacogenomics may potentially have such a profound influence on scientific research and the pharmaceutical industry, the practice of medicine and society at large, that this will generate its own unique dynamic, which will require new ethical research. We suggest that the notion of 'responsibility' will be a major focus of such research.  相似文献   

12.
We develop a conceptual framework for the understanding of animal personalities in terms of adaptive evolution. We focus on two basic questions. First, why do behavioural types exhibit limited behavioural plasticity, that is, behavioural correlations both across contexts and over time? Second, how can multiple behavioural types coexist within a single population? We emphasize differences in 'state' among individuals in combination with state-dependent behaviour. Some states are inherently stable and individual differences in such states can explain stable differences in suites of behaviour if it is adaptive to make behaviour in various contexts dependent on such states. Behavioural stability and cross-context correlations in behaviour are more difficult to explain if individual states are potentially more variable. In such cases stable personalities can result from state-dependent behaviour if state and behaviour mutually reinforce each other by feedback mechanisms. We discuss various evolutionary mechanisms for the maintenance of variation (in states and/or behaviour), including frequency-dependent selection, spatial variation with incomplete matching between habitat and phenotype, bet-hedging in a temporally fluctuating environment, and non-equilibrium dynamics. Although state differences are important, we also discuss how social conventions and social signalling can give rise to adaptive personality differences in the absence of state differences.  相似文献   

13.
In this work a new equation which describes the time evolution of bimolecular reactions is derived and tested by experiment. The equation is general and the results show that second-order reactions of any simple type may be accurately described by a quotient of exponential functions. The model and reagent concentration dependent observed rate constants show a complex non-linear behaviour when experimental conditions deviate from pseudo-first order nevertheless reducing to the well-known linear dependence when pseudo-first order conditions are met.  相似文献   

14.
Ethology is the biological study of behaviour and concerns itself with questions about the causes, functions, evolution and development of aspects of behaviour. These different questions are illustrated with examples from the study of bird song. This subject has had most impact on understanding of developmental issues, showing the intricate interplay between genes and environment during ontogeny. Work on the evolution of song has involved comparison between closely related species to see how their songs have changed since separation, but also the shorter term cultural evolution that occurs when song is passed from one animal to another by learning. Studies of function, while fraught with difficulties, have revealed that song can have a variety of advantages. As far as causes are concerned, some impressive discoveries have recently been made on the neural basis of song. The need for such work to be complemented by studies of behaviour at the level of the whole animal is stressed, and studies of song sequencing are used to illustrate this.  相似文献   

15.
Feticide, the practice of terminating the life of an otherwise viable fetus in utero, has become an increasingly common practice in obstetric centres around the globe, a concomitant of antenatal screening technologies. This paper examines this expanding practice in light of the concept of human dignity. Although it is assumed from the outset that even viable human fetuses are not persons and as such do not enjoy full membership in the moral community, it is argued that the fact that these are nevertheless human fetuses affords them prima facie moral status. Thus even those who accept a liberal position with regard to therapeutic abortion, should be concerned about these more recent developments. Indeed, how we treat viable human fetuses has implications for our prospective treatment of other human non-persons and could undermine the common human dignity we all share.  相似文献   

16.
We experimentally investigated the interactions between two parasites known to manipulate their host's phenotype, the trematodes Acanthoparyphium sp. and Curtuteria australis, which infect the cockle Austrovenus stutchburyi. The larval stages of both species encyst within the tissue of the bivalve's muscular foot, with a preference for the tip of the foot. As more individuals accumulate at that site, they impair the burrowing behaviour of cockles and increase the probability of the parasites' transmission to a bird definitive host. However, individuals at the foot tip are also vulnerable to non-host predators in the form of foot-cropping fish which selectively bite off the foot tip of exposed cockles. Parasites encysted at the foot base are safe from such predators although they do not contribute to altering host behaviour, but nevertheless benefit from host manipulation as all parasites within the cockle are transmitted if it is ingested by a bird. Experimental infection revealed that Acanthoparyphium sp. and C. australis have different encystment patterns within the host, with proportionally fewer Acanthoparyphium metacercariae encysting at the foot tip than C. australis. This indicates that Acanthoparyphium may benefit indirectly from C. australis and incur a lower risk of non-host predation. However, in co-infections, not only did C. australis have higher infectivity than Acanthoparyphium, it also severely affected the latter's infection success. The asymmetrical strategies and interactions between the two species suggest that the advantages obtained from exploiting the host manipulation efforts of another parasite might be offset by traits such as reduced competitiveness in co-infections.  相似文献   

17.
A central role of brain mitochondria in regulating and influencing social behaviour is emerging. In addition to its important roles as the “powerhouses” of the cell, mitochondria possess a plethora of cellular functions, such as regulating ion homeostasis, neurotransmitter levels, and lipid metabolism. Findings in the last decade are revealing an integral role for mitochondria in the regulation of behaviours, including those from the social domain. Here, we discuss recent evidence linking mitochondrial functions and dynamics to social behaviour and deficits, including examples in which social behaviours are modulated by stress in the context of mitochondrial changes, as well as potential therapeutic strategies and outstanding questions in the field.  相似文献   

18.
Environmental philosophers spend considerable time drawing the divide between humans and the rest of nature. Some argue that humans and our actions are unnatural. Others allow that humans are natural, but maintain that humans are nevertheless distinct. The motivation for distinguishing humans from the rest of nature is the desire to determine what aspects of the environment should be preserved. The standard view is that we should preserve those aspects of the environment outside of humans and our influence. This paper examines the standard view by asking two questions. First, are the suggested grounds for distinguishing humans from the rest of the environment viable? Second, is such a distinction even needed for determining what to preserve? The paper concludes that debates over whether humans are natural and whether humans are unique are unhelpful when deciding what to preserve.  相似文献   

19.
A wonderfully lucid framework for the ways to understand animal behaviour is that represented by the four ‘whys’ proposed by Tinbergen (1963). For much of the past three decades, however, these four avenues have been pursued more or less in parallel. Functional questions, for example, have been addressed by behavioural ecologists, mechanistic questions by psychologists and ethologists, ontogenetic questions by developmental biologists and neuroscientists and phylogenetic questions by evolutionary biologists. More recently, the value of integration between these differing views has become apparent. In this brief review, we concentrate especially on current attempts to integrate mechanistic and functional approaches.

Most of our understanding of learning and memory in animals comes from the psychological literature, which tends to use only rats or pigeons, and more occasionally primates, as subjects. The underlying psychological assumption is of general processes that are similar across species and contexts rather than a range of specific abilities. However, this does not seem to be entirely true as several learned behaviours have been described that are specific to particular species or contexts. The first conspicuous exception to the generalist assumption was the demonstration of long delay taste aversion learning in rats (Garcia et al., 1955), in which it was shown that a stimulus need not be temporally contiguous with a response for the animal to make an association between food and illness. Subsequently, a number of other examples, such as imprinting and song learning in birds (e.g., Bolhuis and Honey, 1998; Catchpole and Slater, 1995; Horn, 1998), have been thoroughly researched. Even in these cases, however, it has been typical for only a few species to be studied (domestic chicks provide the ‘model’ imprinting species and canaries and zebra finches the song learning ‘models’). As a result, a great deal is understood about the neural underpinnings and development of the behaviour, but substantially less is understood about interspecific variation and whether variation in behaviour is correlated with variation in neural processing (see review by Tramontin and Brenowitz, 2000 but see ten Cate and Vos, 1999).  相似文献   


20.
Natural enemies such as predators and parasites are known to shape intraspecific variability of behaviour and personality in natural populations, yet several key questions remain: (i) What is the relative importance of predation vs. parasitism in shaping intraspecific variation of behaviour across generations? (ii) What are the contributions of genetic and plastic effects to this behavioural divergence? (iii) And to what extent are responses to predation and parasitism repeatable across independent evolutionary lineages? We addressed these questions using Trinidadian guppies (Poecilia reticulata) (i) varying in their exposure to dangerous fish predators and Gyrodactylus ectoparasites for (ii) both wild‐caught F0 and laboratory‐reared F2 individuals and coming from (iii) multiple independent evolutionary lineages (i.e. independent drainages). Several key findings emerged. First, a population's history of predation and parasitism influenced behavioural profiles, but to different extent depending on the behaviour considered (activity, shoaling or boldness). Second, we had evidence for some genetic effects of predation regime on behaviour, with differences in activity of F2 laboratory‐reared individuals, but not for parasitism, which had only plastic effects on the boldness of wild‐caught F0 individuals. Third, the two lineages showed a mixture of parallel and nonparallel responses to predation/parasitism, with parallel responses being stronger for predation than for parasitism and for activity and boldness than for shoaling. These findings suggest that different sets of behaviours provide different pay‐offs in alternative predation/parasitism environments and that parasitism has more transient effects in shaping intraspecific variation of behaviour than does predation.  相似文献   

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