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911.
In their recent book, Is Inequality Bad for Our Health?, Daniels, Kennedy, and Kawachi claim that to “act justly in health policy, we must have knowledge about the causal pathways through which socioeconomic (and other) inequalities work to produce differential health outcomes.” One of the central problems with this approach is its dependency on “knowledge about the causal pathways.” A widely held belief is that the randomized clinical trial (RCT) is, and ought to be the “gold standard” of evaluating the causal efficacy of interventions. However, often the only data available are non-experimental, observational data. For such data, the necessary randomization is missing. Because the randomization is missing, it seems to follow that it is not possible to make epistemically warranted claims about the causal pathways. Although we are not sanguine about the difficulty in using observational data to make warranted causal claims, we are not as pessimistic as those who believe that the only warranted causal claims are claims based on data from (idealized) RCTs. We argue that careful, thoughtful study design, informed by expert knowledge, that incorporates propensity score matching methods in conjunction with instrumental variable analyses, provides the possibility of warranted causal claims using observational data.  相似文献   
912.
ABSTRACT— Hemispheric specialization has long been considered a uniquely human trait associated with the evolution of language and handedness. Recent studies in a host of vertebrate species have reported evidence of population-level behavioral and brain asymmetries, challenging the claims for the uniqueness of hemispheric specialization to the human species. Here we summarize the findings in nonhuman species and discuss the adaptive significance and potential costs of lateralization of function.  相似文献   
913.
Under-recognition of somatic symptoms associated with panic in primary care settings results in unnecessary and costly diagnostic procedures and inappropriate referrals to cardiologists, gastroenterologists, and neurologists. In the current study specialists’ knowledge regarding the nature and treatment of panic were examined. One-hundred and fourteen specialists completed a questionnaire assessing their knowledge about panic attacks, including their perceptions of psychologists’ role in treating panic. Respondents answered 51% of knowledge items correctly. Although most knew the definition of a panic attack, they knew less about clinical features of panic and its treatment. Specifically, whereas 97.4% believed medication effectively relieves panic symptoms, only 32.5% knew that cognitive-behavioral therapy (CBT) is a first-line treatment. Only 6% reported knowing how to implement CBT, and only 56.1% recognized that psychologists could effectively treat panic. These findings demonstrate significant gaps in specialists’ knowledge about panic and the need to enhance physician knowledge about panic attacks and their treatment.  相似文献   
914.
915.
The lack of standardized instruments to evaluate communication disorders related to the right hemisphere was verified. A new evaluation tool was developed: Protocole Montréal d'Evaluation de la Communication--Protocole MEC, adapted to Brazilian Portuguese--Bateria Montreal de Avalia??o da Comunica??o--Bateria MAC (Montreal Evaluation of Communication Battery). The purpose was to present stratified normative data by age and educational level, and to verify the reliability parameters of the MEC Battery. 300 individuals, between the ages of 19 and 75 years, and levels of formal education between 2 and 35 years, participated in this study. They were divided equally into six normative groups, according to three age categories (young adults, intermediary age, and seniors) and two educational levels (low and high). Two procedures were used to check reliability: Cronbach alpha and reliability between evaluators, Results were established at the 10th percentile, and an alert point per task for each normative group. Cronbach's alpha was, in general, between .70 and .90 and the average rate of agreement between evaluators varied from .62 to .94. Standards of age and education were established. The reliability of this instrument was verified. The psychometric legitimization of the MEC Battery will contribute to the diagnostic process for communicative disorders.  相似文献   
916.
To cope with environmental variability, animals should gather and use information to reduce uncertainty. In insect parasitoids, associative learning has been widely documented in the context of host foraging. However, despite its potential adaptive value, the insect food searching strategy and cues used to search are poorly understood. In this study, we examined the ability of hymenopteran Venturia canescens females to associate food to a visual cue. To broaden the scope of our results, experiments were performed with both arrhenotokous (sexual) and thelytokous (asexual) individuals. The wasps showed innate attraction for yellow and orange stimuli when presented versus blue stimuli. When trained to associate a food reward with one of the attractive colours (orange), they significantly moved from a distance towards the colour previously associated with food. The choice of the innately preferred colour (yellow) was not modified by associative learning. In the context of food foraging, this study is the first to show associative learning using visual stimuli in a parasitoid and active choice of this colour. This ability gives new insights concerning potential food sources for V. canescens in the field, since flowers are sugar sources, which emit colour signals.  相似文献   
917.
The focus of this commentary is twofold. First, I examine Faiciuc’s attempts to counter symbolic computationalism as a major theoretical framework for the study of deductive reasoning. Second, I wish to see how far the author goes in her defense of Dynamic Systems Approaches (DSAs) as a more promising framework for explaining logical reasoning. When reading her work, I posed two versions of the same for/against question to myself: How strong is the case against symbolic computationalism? And, on the basis of the author’s argumentation, would one feel justified in adopting DSAs instead? I examine each question in turn, and come to similar conclusions. The article by Faiciuc tackles issues of relevance to any serious effort toward reflecting on the two perspectives being compared. Unfortunately, however, references to studies supporting her claims are rather thin. A better-informed answer to the question raised in the title of the article is still to be given.  相似文献   
918.
The value of the results of the inverse dynamic analysis procedures used in the study of human tasks is dependent on the quality of the kinematic and kinetic data supplied to the biomechanical model that supports it. The kinematic data, containing the position, velocity and acceleration of all anatomical segments of the biomechanical model, result from the reconstruction of human spatial motion by means of the evaluation of the anatomic points positions that enable to uniquely define the position of all anatomical segments. Furthermore, the motion data must be kinematically consistent with the structure of the biomechanical model used in the analysis. The traditional photogrammetric methodologies used for the spatial reconstruction of the human motion require images of two or more calibrated and synchronized cameras. This is due to the fact that the projection of each anatomical point is described by two linear equations relating its three spatial coordinates with the two coordinates of the projected point. The need for the image of another camera arises from the fact that a third equation is necessary to find the original spatial position of the anatomical point. The methodology proposed here substitutes the projection equations of the second camera with the kinematic constraint equations associated with a biomechanical model in the motion reconstruction process. In the formulation the system of equations arising from the point projections and biomechanical model kinematic constraints, representing the constant length of the anatomical segments, are solved simultaneously. Because the system of equations has multiple solutions for each image, a strategy based on the minimization of a cost function associated to the smoothness of the reconstructed motion is devised. It is shown how the process is implemented computationally avoiding any operator intervention during the motion reconstruction for a given time period. This leads to an automated computer procedure that ensures the uniqueness of the reconstructed motion. The result of the reconstruction process is a set of data that is kinematically consistent with the biomechanical model used. Through applications of the proposed methodology to several sports exercises its benefits and shortcomings are discussed.  相似文献   
919.
920.
Families are increasingly integrating computing technologies into their everyday activities, expanding the range of external influence upon them. For many families, basic notions of 'home' are undergoing shifts as large-scale cultural and economic changes occur that are related to the 'Information age' and as family members spend more time on the Internet and with advanced communications technologies. The Internet is also providing the backdrop for a number of critical family problems, as many counsellors are discovering in their therapy efforts. This article explores the social construction of the various computer hazards that households are encountering, such as computer addiction and children's access to on-line pornography. For example, some parents label deep-seated family issues as 'technological' problems because of the involvement of the computer, while others overlook or deny the possible influences of technologies. The article discusses these issues in terms of constructivist counselling perspectives that are sensitive to cultural and environmental contexts. It outlines some of the specific strategies for countering these problems that counsellors can utilise with their clients (such as solution-focused approaches). It also discusses how counsellors can help household heads to define and deal with their rapidly changing responsibilities in these new realms.  相似文献   
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