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81.
Tim Kraft 《Synthese》2014,191(12):2617-2632
Transmission arguments against closure of knowledge base the case against closure on the premise that a necessary condition for knowledge is not closed. Warfield argues that this kind of argument is fallacious whereas Brueckner, Murphy and Yan try to rescue it. According to them, the transmission argument is no longer fallacious once an implicit assumption is made explicit. I defend Warfield’s objection by arguing that the various proposals for the unstated assumption either do not avoid the fallacy or turn the central premise of the transmission argument, namely that a necessary condition is not closed, into a redundant and superfluous premise. I conclude that Warfield’s advice is still to be heeded: Arguments against closure must not rely essentially on the premise that a necessary condition for knowledge is not closed.  相似文献   
82.
The traditional Square of Opposition consists of four sentence types. Two are universal and two particular; two are affirmative and two negative. Examples, where ‘S’ and ‘P’ designate the subject and the predicate, are: ‘every S is P’, ‘no S is P’, ‘some S is P’ and ‘some S is not P’. Taking the usual sentences of the square of opposition, quantifying over their predicates exhibits non-standard sentence forms. These sentences may be combined into non-standard Squares of Opposition (an Octagon in this case), and they reveal a new relationship not found in the usual Square. Medieval logicians termed ‘disparatae’ pairs of sentences like ‘every S is some P’ and ‘some S is every P’, which are neither subaltern nor contrary, neither contradictory nor subcontrary. Walter Redmond has designed a special language L to express the logical form of these sentences in a precise way. I will use this language to show how Squares of Opposition, standard and non-standard, form a complex network of relations which bring to light the subtleties contained in this traditional doctrine.  相似文献   
83.
The combination of investigating child and family characteristics sheds light on the constellation of risk factors that can ultimately lead to dyslexia. This family-risk study examines plausible preschool risk factors and their specificity. Participants (N?=?196, 42 % girls) included familial risk (FR) children with and without dyslexia in Grade 3 and controls. First, we found impairments in phonological awareness, rapid naming, and letter knowledge in FR kindergartners with later dyslexia, and mild phonological-awareness deficits in FR kindergartners without subsequent dyslexia. These skills were better predictors of reading than arithmetic, except for rapid naming. Second, the literacy environment at home was comparable among groups. Third, having a dyslexic parent and literacy abilities of the non-dyslexic parent related to offspring risk of dyslexia. Parental literacy abilities might be viewed as indicators of offspring’s liability for literacy difficulties, since parents provide offspring with genetic and environmental endowment. We propose an intergenerational multiple deficit model in which both parents confer cognitive risks.  相似文献   
84.
Trait theories of vulnerability to bipolar disorder (BD) are increasingly common in the literature, yet poorly understood. The aim of the current study was to complement existing knowledge of trait theories by investigating two biological rhythm features often associated with BD – eveningness and seasonality – in a sample assessed as vulnerable to the disorder. Two hundred and thirteen participants completed an online survey consisting of the General Behavior Inventory, Seasonal Pattern Assessment Questionnaire, and Morningness-Eveningness Questionnaire. Hierarchical regressions controlling for sex and age showed that greater levels of seasonality and a tendency towards an eveningness chronotype were weak, but significant predictors of the BD vulnerability trait. When the traits of vulnerability to depression and mania were investigated separately, seasonality and eveningness were significant predictors of the former, but only seasonality was a significant predictor of the latter. The Autumn/Winter pattern of seasonality was a weak predictor of trait vulnerability to mania but not depression. The current findings advance understanding of the BD vulnerability trait, and may have consequences for the behavioural management of those who are considered to be ‘at risk’ of the disorder.  相似文献   
85.
The search for different options before making a consequential choice is a central aspect of many important decisions, such as mate selection or purchasing a house. Despite its importance, surprisingly little is known about how search and choice are affected by the observed and objective properties of the decision problem. Here, we analyze the effects of two key properties in a binary choice task: the options' observed and objective values, and the variability of payoffs. First, in a large public data set of a binary choice task, we investigate how the observed value and variability relate to decision‐makers' efforts and preferences during search. Furthermore, we test how these properties influence the chance of correctly identifying the objectively maximizing option, and how they affect choice. Second, we designed a novel experiment to systematically analyze the role of the objective difference between the options. We find that a larger objective difference between options increases the chance for correctly identifying the maximizing option, but it does not affect behavior during search and choice. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
86.
Tactile expertise, resulting from extensive use of hands, has previously been shown to improve tactile perception in blind people and musicians and to be associated with changes in the central processing of tactile information. This study investigated whether expertise, due to precise and deliberate use of the fingers at work, relates to improved tactile perception and whether this expertise interacts with age. A tactile pattern and a frequency discrimination task were conducted while ERPs were measured in experts and nonexperts of two age groups within middle adulthood. Independently of age, accuracy was better in experts than in nonexperts in both tasks. Somatosensory N70 amplitudes were larger with increasing age and for experts than for nonexperts. P100 amplitudes were smaller in experts than in nonexperts in the frequency discrimination task. In the pattern discrimination task, P300 difference wave amplitude was reduced in experts and late middle-aged adults. In the frequency discrimination task, P300 was more equally distributed in late middle-aged adults. We conclude that extensive, dexterous manual work leads to acquisition of tactile expertise and that this expertise might delay, but not counteract, age effects on tactile perception. Comparable neurophysiological changes induced by age and expertise presumably have different underlying mechanisms. Enlarged somatosensory N70 amplitudes might result from reduced inhibition in older adults but from enhanced, specific excitability of the somatosensory cortex in experts. Regarding P300, smaller amplitudes might indicate fewer available resources in older adults and, by contrast, a reduced need to engage as much cognitive effort to the task in experts.  相似文献   
87.
In the Arab and Muslim countries, there are several taboos of sexuality. To overcome the latter, and to distinguish between cultural and scientific data, sexual education is a key measure, especially during medical studies. The purpose of this study was to assess the knowledge of the Tunisian medical trainees and to identify their sources of information concerning sexuality. We conducted a survey among medical trainees of the faculty of medicine of Sfax, in Tunisia. An anonymous questionnaire was distributed to 171 and completed by 157 trainees (91.8%). The sources of knowledge about sexuality were: friends (81.5%; N = 128), internet (77.1%; N = 121), television and movies (68.2%; N = 107), courses at the faculty (40.1%; N = 63) and parents (22.9%; N = 36). The score of correct answers was higher than or equal to 75% for 28 trainees (17.8%). It was on average 63.3%. It was correlated with male gender (p = 0.006), being a second-year trainee (p = 0.017) and television and movies as a source of knowledge about sexuality (p = 0.008). Masturbation was considered pathological by 17.2% of participants (N = 27). A 5-min period of intercourse was deemed sufficient to have a female orgasm by 44 trainees (28%). Andropause and menopause are inconsistent with a satisfying sexuality according to 44.6% (N = 70) and 56.1% (N = 88) of the participants respectively.  相似文献   
88.
Employing a sample of 197 employee-supervisor dyads, we explore whether employees’ attitudes and underlying motivation for engaging in organizational citizenship behaviours (OCBs) differentially relate to supervisors’ assessments of their individual performance and reward recommendations. We theorized that employees who perform OCBs with self-serving motives would be low on affective commitment and high on equity sensitivity, and that such individuals would receive lower performance ratings and fewer reward recommendations than those who are high on affective commitment, low on equity sensitivity, and more selflessly motivated. Our results suggest that employees with high affective commitment, low equity sensitivity, and high selfless motives were more likely to receive positive supervisor performance ratings and high reward recommendations. We also found that affective commitment moderated the mediating path of prosocial values (a selfless motive) on the relationship between OCBs and reward recommendations. Practical implications and future research directions are discussed.  相似文献   
89.
90.
Little is known about research misconduct within industry and how it compares to universities, even though a lot of biomedical research is performed by–or in collaboration with–commercial entities. Therefore, we sent an e-mail invitation to participate in an anonymous computer-based survey to all university researchers having received a biomedical research grant or scholarship from one of the two national academic research funders of Belgium between 2010 and 2014, and to researchers working in large biomedical companies or spin-offs in Belgium. The validated survey included questions about various types of research misconduct committed by respondents themselves and observed among their colleagues in the last three years. Prevalences of misconduct were compared between university and industry respondents using binary logistic regression models, with adjustments for relevant personal characteristics, and with significance being accepted for p < 0.01. The survey was sent to 1766 people within universities and an estimated 255 people from industry. Response rates were 43 (767/1766) and 48% (123/255), and usable information was available for 617 and 100 respondents, respectively. In general, research misconduct was less likely to be reported by industry respondents compared to university respondents. Significant differences were apparent for one admitted action (gift authorship) and three observed actions (plagiarism, gift authorship, and circumventing animal-subjects research requirements), always with lower prevalences for industry compared to universities, except for plagiarism. This survey, based on anonymous self-report, shows that research misconduct occurs to a substantial degree among biomedical researchers from both industry and universities.  相似文献   
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