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211.
Janssen D Schöllhorn WI Newell KM Jäger JM Rost F Vehof K 《Human movement science》2011,30(5):966-975
The aim of the study was to train and test support vector machines (SVM) and self-organizing maps (SOM) to correctly classify gait patterns before, during and after complete leg exhaustion by isokinetic leg exercises. Ground reaction forces were derived for 18 gait cycles on 9 adult participants. Immediately before the trials 7–12, participants were required to completely exhaust their calves with the aid of additional weights (44.4 ± 8.8 kg). Data were analyzed using: (a) the time courses directly and (b) only the deviations from each individual’s calculated average gait pattern. On an inter-individual level the person recognition of the gait patterns was 100% realizable. Fatigue recognition was also highly probable at 98.1%. Additionally, applied SOMs allowed an alternative visualization of the development of fatigue in the gait patterns over the progressive fatiguing exercise regimen. 相似文献
212.
213.
Building a Committed Hospice Volunteer Workforce—Do Variables at the Experience Stage Matter?
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Claudia Schusterschitz Magdalena Flatscher‐Thöni Andrea M. Leiter‐Scheiring Willi Geser 《Journal of community & applied social psychology》2014,24(5):422-438
Volunteers are crucial to the survival of non‐profit organisations, who therefore have a fundamental interest in sustaining voluntary engagement over time. A central variable regarding sustained voluntary engagement is volunteers' organisational commitment, which has so far been a neglected research issue. The study at hand therefore explicitly focuses on hospice volunteers' commitment. Starting from the assumption that variables at the experience stage of volunteerism may be relevant in predicting volunteer commitment, questionnaire data on volunteers' motives, motive fulfilment and role identity were collected in a sample of hospice volunteers (N = 276). Results of multiple regression analyses show positive relationships between altruistic motive fulfilment and a volunteer role identity on the one hand and volunteer commitment on the other. Observed interaction effects imply that altruistic motive fulfilment is of importance both at the initial phase of volunteering and for long‐term volunteers. Moreover, interaction effects provide evidence that the fulfilment of egoistic motives is of particular importance amongst volunteers to whom egoistic motives are central. Thus, the fulfilment of altruistic motives and facilitating the development of a volunteer role identity should be permanent concerns in building a committed workforce. Egoistic motive fulfilment in contrast is of special relevance, when egoistic motives for volunteering are strong. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
214.
Naming an object in the context of other objects requires the selection and processing of the target object at different levels, while the processing of competing representations activated by context objects has to be constrained. At what stage are these competing representations attenuated? To address this question, we presented pairs of target and context objects that were either similar in visual shape (e.g., umbrella–palm tree) or dissimilar in visual shape (e.g., umbrella–ladder), so that the context object would attract various amounts of attention. The activation of the context object at different levels of processing was assessed by means of auditory distractors (semantically related, or phonologically related, or unrelated to the context object). Semantic and phonological distractor effects were observed for shape-related object pairs, but not for unrelated object pairs. This finding suggests that context objects do not activate their associated lexical representations to any substantial amount, unless they capture attention. In that case, they undergo full lexical processing up to a phonological level. Implications for models of word production are discussed. 相似文献
215.
In a valence induction task, one color acquired positive valence by indicating the chance to win money (in the case of fast and correct responses), and a different color acquired negative valence by indicating the danger to lose money (in the case of slow or incorrect responses). In the additional-singleton trials of a visual search task, the task-irrelevant singleton color was either the positive one, the negative one, or one of two neutral colors. We found an additional-singleton effect (i.e., longer RTs with a singleton color than in the no-singleton control condition). This effect was significantly increased for the two valent colors (with no differences between them) relative to the two neutral colors (with no differences between them, either). This result favors the hypothesis that the general relevance of stimuli elicits attentional capture, rather than the negativity bias hypothesis. 相似文献
216.
Infants use signals from others to guide their behavior when confronted with novel situations, a process called ‘social referencing’ (SR). Via SR, signs of parental anxiety can lead to infant anxiety. Little is known about differences in the effect of paternal and maternal SR signals on child anxiety. Using a visual cliff paradigm, we studied whether SR processes between fathers and their infants differed from mothers and their infants. Eighty‐one infants aged 10–15 months were randomly assigned to conduct the visual cliff task with their father (n = 41) or mother (n = 40). The infant was placed on the shallow side of the cliff and the parent, standing at the deep side, was instructed to encourage the infant to cross. Results showed that although mothers showed more intense facial expressions of encouragement than fathers, no differences occurred in how fast, and with how much anxiety, infants crossed the cliff with fathers and mothers. However, path analyses showed that paternal, but not maternal, expressed anxiety was positively associated with infant expressed anxiety and avoidance. For infants who participated with their mother, infants' anxious temperament was negatively associated with infant avoidance of the cliff. Infant anxious temperament moderated the link between paternal expressed anxiety and infant avoidance: the higher the level of infant anxious temperament the stronger the positive association between paternal expressed anxiety and infant's avoidance of the cliff. Lastly, parental encouragement was unrelated to infant expressed anxiety and avoidance. Our results suggest that SR processes between fathers and their infants differ from those between mothers and their infants. 相似文献
217.
Caitlin E. V. Mahy Nora Vetter Nina Kühn-Popp Carolin Löcher Susan Krautschuk Matthias Kliegel 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2014,21(2):129-145
The primary aim of this study was to examine the impact of an inhibition manipulation on the effect of age on theory of mind (ToM) in an ecologically valid, affective ToM task. Participants were 30 young and 30 old adults. The Cambridge Mindreading Face-Voice Battery was used to measure ToM; in addition, measures of fluid and crystallized intelligence were taken. Participants were subjected to three levels of inhibitory demand during ToM reasoning: emotional inhibition, non-emotional inhibition, and no inhibition. Old adults performed worse than young adults. The emotional and non-emotional inhibition conditions resulted in worse ToM performance compared to the no inhibition condition. There were no differences in the impact of the inhibition conditions on old and young adults. Regression analyses suggested that old adults’ crystallized intelligence was a significant predictor of ToM performance, whereas it did not predict young adults’ ToM performance. Results are discussed in terms of verbal ability as a possible compensatory mechanism in coping with verbal inhibitory load in ToM reasoning. 相似文献
218.
Petra Sandberg Michael Rönnlund Lars Nyberg Anna Stigsdotter Neely 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2014,21(5):577-605
There is a growing body of research on the modifiability of executive functions in different stages of life. Previous studies demonstrate robust training effects but limited transfer in younger and particularly in older adults. The aim of the present study was to investigate whether a theoretically derived intervention for executive functioning, addressing several basic processes (updating, shifting, and inhibition), can induce transfer effects in early and late adulthood. Fifty-nine healthy adults, 29 young and 30 older adults, were randomly assigned to either training or no-contact control groups. The training groups received 15 sessions of executive process training for about 45 min/session during 5 weeks. A test battery including a criterion task and near, intermediate, and far transfer tasks was administered before and after training. Results showed pronounced age-equivalent gains on the criterion task. Near transfer was seen to non-trained updating and inhibition tasks for the young and older trained participants. However, only the young adults showed intermediate transfer to two complex working memory tasks. No far transfer effects were seen for either age group. These findings provide additional evidence for age-related constraints in the ability to generalize acquired executive skills, and specifically show that training of multiple executive processes is not sufficient to foster transfer beyond the very near in older adults. 相似文献
219.
Sebastian Rödl 《Philosophical explorations》2014,17(3):304-316
The second person is often set in contrast to the first person. And there is a contrast. It does not reside in a difference of what is thought as I from what is thought as you. For that is not different. The contrast is that of monadic and dyadic predication, action and transaction. It is the contrast, not of I and You, but of I and I–You. The second person does not add a You to an I. It divides the I and makes it a relation. We consider, first, the form of predication that is common to first- and second-person thought. Then, we define the second person as a species of this form of thought. Last, we find the source and condition of this form of thought in a thought of this very form. This thought, being the source of its own form, is one of which one cannot be conscious from outside it. It is a last word, or, better, a first word.1 相似文献
220.
The protection of offspring against predators and competitors is especially important in organisms using spatially separated breeding resources, impeding the offspring’s chances to escape. One example of such isolated reproductive resources are phytotelmata (small water bodies in plant axils), exploited by the Neotropical poison frog Ranitomeya variabilis (Dendrobatidae) for both clutch and tadpole deposition. Because poison frog tadpoles are often cannibalistic, parents tend to avoid deposition with conspecifics. Previous studies have shown that this avoidance is based on chemical cues produced by conspecific tadpoles. Further, cues produced by phylogenetically less-related tadpoles (Bufonidae) were avoided for clutch but not tadpole depositions. We analyzed how the different responses to tadpole cues are triggered. We tested the reactions of parental R. variabilis to tadpole cues of species differing in two aspects: whether or not they are dendrobatids, and whether or not they reproduce in phytotelmata. We found that for clutch deposition, tadpole cues were always avoided, i.e., all tadpoles were treated by the frogs as if they pose a danger to the eggs. However, responses varied for tadpole depositions: while dendrobatid larvae living in phytotelmata were avoided, those breeding in streams were not. Non-poison frog tadpoles were ignored when associated with habitat other than phytotelmata, but they were preferred when living in phytotelmata. This suggests that both phylogeny and tadpole habitat are important triggers for the decisions made by R. variabilis. Only tadpoles using the same breeding resources are considered as relevant for the frog’s own larvae (i.e., as a potential danger or food resource), while further decisions are related to evolutionary relationship. 相似文献