925 resultados para Johnston, Victor S.: Why we feel
Resumo:
Antisaccade errors are attributed to failure to inhibit the habitual prosaccade. We investigated whether the amount of information about the required response the patient has before the trial begins also contributes to error rate. Participants performed antisaccades in five conditions. The traditional design had two goals on the left and right horizontal meridians. In the second condition, stimulus-goal confusability between trials was eliminated by displacing one goal upward. In the third, hemifield uncertainty was eliminated by placing both goals in the same hemifield. In the fourth, goal uncertainty was eliminated by having only one goal, but interspersed with no-go trials. The fifth condition eliminated all uncertainty by having the same goal on every trial. Antisaccade error rate increased by 2% with each additional source of uncertainty, with the main effect being hemifield information, and a trend for stimulus-goal confusability. A control experiment for the effects of increasing angular separation between targets without changing these types of prior response information showed no effects on latency or error rate. We conclude that other factors besides prosaccade inhibition contribute to antisaccade error rates in traditional designs, possibly by modulating the strength of goal activation.
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The disposal of municipal solid waste is believed to emit foul odor, threaten groundwater, and increase road congestion. As remote regional landfills have replaced local town dumps, these costs are no longer internalized by garbage-producing households or their municipalities. Instead, rural property owners located adjacent to large regional landfills and along the roadways accessing those landfills bear the external costs of garbage disposal. This paper uses a comprehensive nine-year panel data set of aggregated state data to empirically examine why 8,937 municipalities continue to operate costly recycling programs designed to reduce the external costs of garbage disposal. Results suggest that local tastes for recycling drive municipal decisions. If household preferences for recycling are short lived, then we can expect a future decrease in the number of municipal recycling programs. Recent data indicate the number of recycling programs in operation in the U.S. has indeed fallen.
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Human sexual determination is initiated by a cascade of genes that lead to the development of the fetal gonad. Whereas development of the female external genitalia does not require fetal ovarian hormones, male genital development requires the action of testicular testosterone and its more potent derivative dihydrotestosterone (DHT). The "classic" biosynthetic pathway from cholesterol to testosterone in the testis and the subsequent conversion of testosterone to DHT in genital skin is well established. Recently, an alternative pathway leading to DHT has been described in marsupials, but its potential importance to human development is unclear. AKR1C2 is an enzyme that participates in the alternative but not the classic pathway. Using a candidate gene approach, we identified AKR1C2 mutations with sex-limited recessive inheritance in four 46,XY individuals with disordered sexual development (DSD). Analysis of the inheritance of microsatellite markers excluded other candidate loci. Affected individuals had moderate to severe undervirilization at birth; when recreated by site-directed mutagenesis and expressed in bacteria, the mutant AKR1C2 had diminished but not absent catalytic activities. The 46,XY DSD individuals also carry a mutation causing aberrant splicing in AKR1C4, which encodes an enzyme with similar activity. This suggests a mode of inheritance where the severity of the developmental defect depends on the number of mutations in the two genes. An unrelated 46,XY DSD patient carried AKR1C2 mutations on both alleles, confirming the essential role of AKR1C2 and corroborating the hypothesis that both the classic and alternative pathways of testicular androgen biosynthesis are needed for normal human male sexual differentiation.
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Quantitative data on lung structure are essential to set up structure-function models for assessing the functional performance of the lung or to make statistically valid comparisons in experimental morphology, physiology, or pathology. The methods of choice for microscopy-based lung morphometry are those of stereology, the science of quantitative characterization of irregular three-dimensional objects on the basis of measurements made on two-dimensional sections. From a practical perspective, stereology is an assumption-free set of methods of unbiased sampling with geometric probes, based on a solid mathematical foundation. Here, we discuss the pitfalls of lung morphometry and present solutions, from specimen preparation to the sampling scheme in multiple stages, for obtaining unbiased estimates of morphometric parameters such as volumes, surfaces, lengths, and numbers. This is demonstrated on various examples. Stereological methods are accurate, efficient, simple, and transparent; the precision of the estimates depends on the size and distribution of the sample. For obtaining quantitative data on lung structure at all microscopic levels, state-of-the-art stereology is the gold standard.
Self-conscious emotions and depression: Rumination explains why shame, but not guilt, is maladaptive
Resumo:
Feelings of shame and guilt are factors associated with depression. However, studies simultaneously investigating shame and guilt suggest that only shame has a strong unique effect, although it is not yet clear which psychological processes cause shame and not shame-free guilt to be related to depression. The authors hypothesized that shame, in contrast to guilt, elicits rumination, which then leads to depression. Therefore, in this study we investigated event-related shame and guilt, event-related rumination, and depression among 149 mothers and fathers following family breakup due to marital separation. Data were analyzed using latent variable modeling. The results confirm that shame but not guilt has a strong unique effect on depression. Moreover, the results show that the effect of shame is substantially mediated by rumination. The results are discussed against the background of self-discrepancies and self-esteem.
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A recent article in this journal (Ioannidis JP (2005) Why most published research findings are false. PLoS Med 2: e124) argued that more than half of published research findings in the medical literature are false. In this commentary, we examine the structure of that argument, and show that it has three basic components: 1)An assumption that the prior probability of most hypotheses explored in medical research is below 50%. 2)Dichotomization of P-values at the 0.05 level and introduction of a “bias” factor (produced by significance-seeking), the combination of which severely weakens the evidence provided by every design. 3)Use of Bayes theorem to show that, in the face of weak evidence, hypotheses with low prior probabilities cannot have posterior probabilities over 50%. Thus, the claim is based on a priori assumptions that most tested hypotheses are likely to be false, and then the inferential model used makes it impossible for evidence from any study to overcome this handicap. We focus largely on step (2), explaining how the combination of dichotomization and “bias” dilutes experimental evidence, and showing how this dilution leads inevitably to the stated conclusion. We also demonstrate a fallacy in another important component of the argument –that papers in “hot” fields are more likely to produce false findings. We agree with the paper’s conclusions and recommendations that many medical research findings are less definitive than readers suspect, that P-values are widely misinterpreted, that bias of various forms is widespread, that multiple approaches are needed to prevent the literature from being systematically biased and the need for more data on the prevalence of false claims. But calculating the unreliability of the medical research literature, in whole or in part, requires more empirical evidence and different inferential models than were used. The claim that “most research findings are false for most research designs and for most fields” must be considered as yet unproven.
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Since the discovery of the Ca(2+) spark as an elementary event of cellular Ca(2+) signaling almost 15 years ago, the family of newly described Ca(2+) signal entities has been ever growing. While scientists working in Ca(2+) signaling may have maintained an overview over the specifics of this nomenclature, those outside the field often make the complaint that they feel hopelessly lost. With the present review we collect and summarize systematic information on the many Ca(2+) signaling events described in a variety of tissues and cells, and we emphasize why and how each of them has its own importance. Most of these signals are taking place in the cytosol of the respective cells, but several events have been recorded from intracellular organelles as well, where they may serve their own specific functions. Finally, we also try to convey an integrated view as to why cellular microdomain signaling is of fundamental biological importance.
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Integration of multiple languages into each other and into an existing development environment is a difficult task. As a consequence, developers often end up using only internal DSLs that strictly rely on the constraints imposed by the host language. Infrastructures do exist to mix languages, but they often do it at the price of losing the development tools of the host language. Instead of inventing a completely new infrastructure, our solution is to integrate new languages deeply into the existing host environment and reuse the infrastructure offered by it. In this paper we show why Smalltalk is the best practical choice for such a host language.
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In developed countries, the transition from school to work has radically changed over the past two decades. It has become prolonged, complicated and individualized (Bynner et al., 1997; Walther et al., 2004). Young people used to transition directly from school to stable employment, or with a very short unemployed period. In many European countries, this situation has been changing since the eighties: overall youth unemployment has increased, and many young people experience long periods of unemployment, government training schemes and part-time or temporary jobs. In Japan, this change has taken a decade later to appear, becoming prevalent by the late nineties (Inui, 2003). The transiting process has become not only precarious for young people, but also difficult for society to precisely understand the risks and problems. Traditionally, we have been able to recognize young people's situation by a simple category: in education, employed, in training or unemployed. However, these categories no longer accurately represent young people's state. In Japan, most young people used to move from school directly to full-time employment through the new graduate recruitment system (Inui, 1993). Therefore, in official statistics such as the School Basic Survey, 'employed' includes only those who are in regular employment, while those who are in part-time or temporary work are covered by the categories 'jobless' and 'others'. However, with the increase in non-full-time jobs in the nineties, these categories have become less useful for describing the actual employment conditions of young people. Indeed, this is why, in the late of nineties, the Japanese Ministry of Education changed the category name from 'jobless' to 'others'.
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Since the Sarbanes-Oxley Act was passed in 2002, it has become commonplace in the advertising industry to use creativity-award-show prizes instead of gross income figures to attract new customers. Therefore, achieving a top creativity ranking and winning creativity awards have become high priorities in the advertising industry. Agencies and marketers have always wondered what elements in the advertising creation process would lead to the winning of creativity awards. Although this debate has been dominated by pure speculation about the success of different routines, approaches and strategies in winning creativity awards, for the first time our study delivers an empirical insight into the key drivers of creativity award success. We investigate what strategies and which elements of an advertising campaign are truly likely to lead to winning the maximum number of creativity awards. Using a sample of 108 campaigns, we identify factors that influence campaign success at international advertising award shows. We identify innovativeness and the integration of multiple channels as the key drivers of creativity award success. In contrast to industry beliefs, meaningful or personally connecting approaches do not seem to generate a significant benefit in terms of winning creativity awards. Finally, our data suggest that the use of so-called “fake campaigns” to win more creativity awards does not prove to be effective.
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Over the last couple of decades, the UK experienced a substantial increase in the incidence and geographical spread of bovine tuberculosis (TB), in particular since the epidemic of foot-and-mouth disease (FMD) in 2001. The initiation of the Randomized Badger Culling Trial (RBCT) in 1998 in south-west England provided an opportunity for an in-depth collection of questionnaire data (covering farming practices, herd management and husbandry, trading and wildlife activity) from herds having experienced a TB breakdown between 1998 and early 2006 and randomly selected control herds, both within and outside the RBCT (the so-called TB99 and CCS2005 case-control studies). The data collated were split into four separate and comparable substudies related to either the pre-FMD or post-FMD period, which are brought together and discussed here for the first time. The findings suggest that the risk factors associated with TB breakdowns may have changed. Higher Mycobacterium bovis prevalence in badgers following the FMD epidemic may have contributed to the identification of the presence of badgers on a farm as a prominent TB risk factor only post-FMD. The strong emergence of contact/trading TB risk factors post-FMD suggests that the purchasing and movement of cattle, which took place to restock FMD-affected areas after 2001, may have exacerbated the TB problem. Post-FMD analyses also highlighted the potential impact of environmental factors on TB risk. Although no unique and universal solution exists to reduce the transmission of TB to and among British cattle, there is an evidence to suggest that applying the broad principles of biosecurity on farms reduces the risk of infection. However, with trading remaining as an important route of local and long-distance TB transmission, improvements in the detection of infected animals during pre- and post-movement testing should further reduce the geographical spread of the disease.
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Despite their enormous success the motivation behind user participation in Online Social Networks is still little understood. This study explores a variety of possible incentives and provides an empirical evaluation of their subjective relevance. The analysis is based on survey data from 129 test subjects. Using Structural Equation Modeling, we identified that the satisfaction of the needs for belongingness and the esteem needs through self-presentation together with peer pressure are the main drivers of participation. The analysis of a sub-sample of active users pointed out the satisfaction of the cognitive needs as an additional participation determinant. Based on these findings, recommendations for online social network providers are made.
Resumo:
Monte Carlo simulations arrive at their results by introducing randomness, sometimes derived from a physical randomizing device. Nonetheless, we argue, they open no new epistemic channels beyond that already employed by traditional simulations: the inference by ordinary argumentation of conclusions from assumptions built into the simulations. We show that Monte Carlo simulations cannot produce knowledge other than by inference, and that they resemble other computer simulations in the manner in which they derive their conclusions. Simple examples of Monte Carlo simulations are analysed to identify the underlying inferences.
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The World Trade Organization (WTO) is one of the most judicialized dispute settlement systems in international politics. While a general appreciation has developed that the system has worked quite well, research has not paid sufficient attention to the weakest actors in the system. This paper addresses the puzzle of missing cases of least-developed countries initiating WTO disputes settlement procedures. It challenges the existing literature on developing countries in WTO dispute settlement which predominantly focuses on legal capacity and economic interests. The paper provides an argument that the small universe of ‘actionable cases’, the option of free riding and the assessment of the perceived opportunity costs related to other foreign policy priorities better explain the absence of cases. In addition (and somewhat counterintuitively), we argue that the absence of cases is not necessarily bad news and shows how the weakest actors can use the dispute settlement system in a ‘lighter version’ or in indirect ways. The argument is empirically assessed by conducting a case study on four West African cotton-producing countries (C4) and their involvement in dispute settlement.
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Humans engage in deceptive behavior that negatively affects others. The propensity to deceive is,however, characterized by vast inter-individual heterogeneity that is poorly understood. Attempts to investigate the origins of this heterogeneity have so far mainly relied on subjective measures and have shown little predictive power. Here, we used resting electroencephalography to measure objective and stable individual differences in neural baseline activation in combination with an ecologically valid deception paradigm. Results showed that task-independent baseline activation in the anterior insula, a brain area implicated in mapping internal bodily states and in representing emotional arousal and consciousfeelings, predicts individuals’ propensity for deceptive behavior. The higher the neural baseline activation in this area is, the lower individuals’ propensity to deceive. Moreover, results provide evidence that high baseline activation in the anterior insula is associated with negative affect and dispositional tendencies to avoid aversive emotional situations. These results provide converging neural and psychological evidence that individuals might avoid a deceptive act due to a highly active negative emotional system which would make a deceptive act too stressful and bothersome.