Walking in an environment of moving ground texture

The visual control of global body movements has mainly been studied in terms of the maintenance of balance. The present experiment examined the effect of moving visual surroundings on the speed of locomotion. A virtually boundless optical environment was generated by the projection of a dotted texture on the ground that was reflected on large vertical mirrors fixed along the walls of the room. Subjects' head velocity was recorded over a walking path of about 10 m along the projection surface. In the experimental sessions, the texture was animated and moved at different speeds in the same direction as the subject or in the opposite direction. In the control condition, the projected texture remained motionless and therefore appeared to pass by at the subjects' walking speed. The subjects' task was to maintain a constant walking speed as far as possible over the different conditions. Changes in walking speed give indications of how the processing of optical flow modulates locomotor activity.     

Flow: Beyond Fluidity and Rigidity

The term flow refers to a particular type of experience characterized by feelings of fusion with an on-going activity, effortlessness and fluidity. This article concerns the results of an empirical investigation and phenomenological analysis of this type of experience. The analysis yields a distinction between three phenomenological structures, identified as arising in different combinations within concrete experiences of flow. These results are discussed in relation to the theories of Alfred Schutz and Erving Goffman regarding the organization of experience in everyday life, and in relation to the theory of Otto Friedrich Bollnow regarding moods in everyday life. The results of the analysis are also discussed in relation to different uses of the flow concept in a variety of contexts found in recent theoretical contributions. These differences of usage and approach are explained in the light of the results of the phenomenological analysis, which distinguishes qualitatively different varients within the phenomenon termed flow experience. In conclusion, the need to adopt a broader concept of experience in sociological analysis is emphasized, as well as the need for further empirical studies of the contextual frames of different variants of flow experiences.     

学业自我效能感与在线学习投入的关系：学习动机和心流体验的链式中介作用

为探讨学业自我效能感对在线学习投入的影响及其作用机制,采用学业自我效能感量表、学习动机量表、心流体验量表和在线学习投入量表,对310名在线学习者进行问卷调查。结果发现：（1）学业自我效能感对在线学习投入具有正向预测作用;（2）学习动机和心流体验分别在学业自我效能感和在线学习投入之间起部分中介作用;（3）学习动机、心流体验在学业自我效能感和在线学习投入之间起链式中介作用。     

Ethnographic Interview

For an occupational therapist unfamiliar with a culturally diverse treatment population, ethnographic interview is described as an appropriate method for assessing client group needs. This study describes the use of ethnographic interview as a tool which was culturally sensitive to the occupational behaviors of American Indians and Alaska Natives of the Northwest involved in drug and alcohol treatment. Results of the interviews helped the researcher identify sociocultural factors in the acquisition and maintenance of maladaptive behaviors. Recurring themes of the extended family network, the strength and complexity of social norms and codes, and the pervasiveness of alcohol use among this population are described in review of the literature and results of the interviews. Results of the Tennessee Self-concept Scale revealed an overall measure of self-esteem significantly lower than that of the normed population, and enerally supported rehabilitation issues originally identified by the f iterature and expanded on in the interviews. Implications for treatment discuss acceptance of the therapist by members of the culture, the concept of nonmterference, the role of purposeful activity, cultural identification and assimilation, and the use of group work.     

The effect of tape-recorded relaxation training on well-being,symptoms, and peak expiratory flow rate in adult asthmatics: A pilot study

Abstract

Evidence indicates that psychological stress plays a role in precipitating and exacerbating asthma symptoms and suggests that relaxation techniques aimed at reducing stress and autonomic arousal leads to symptom reduction. This study explored the effect of a tape-recorded relaxation intervention on well-being (mood and stresson). asthma symptoms, and a measure of pulmonary function (PEFR). Twenty adult asthmatics were studied for 21 days in their natural environment using a multiple baseline design. Self-administered relaxation training (including both breathing exercises and muscle relaxation) led to decreased negative mood and stressor report. Reporting of asthma symptoms decreased over time, and PEFR was increased by relaxation training. Asthma medication use was unchanged. Results suggest that tape–recorded relaxation training positively impacts well-being, asthma symptoms. and PEFR in a naturalistic setting. Further study of the potential use of inexpensive tape-recorded interventions in chronic illness is warranted.     

Temperature dependence of the plastic flow behavior of tantalum

Nanoindention has been used to study the plastic flow behavior of bcc Ta(001) in the temperature range 25–200°C. Most notably, it is found that the shape of the load–displacement curves changes with increasing temperature. Only one large discontinuity marking the onset of plasticity is observed in room-temperature experiments, whereas multiple pop-ins separated by elastic reloading segments were observed at 200°C. Detailed analysis of the load–displacement curves indicates that the lattice resistance decreases with increasing temperature, consistent with the mobilization of screw dislocations by thermal activation. Contributions from the oxide layer and/or thermal drift can be excluded.     

Effect of Mg content on Portevin–Le Chatelier band strain in Al–Mg sheet alloys

Experimental measurements of stress drops and band strains in type-B Portevin–Le Chatelier (PLC) bands were carried out for 5xxx series Al–Mg sheets with Mg content between 1.8 and 4.5?wt%. While the stress drops increase with global strain, the band strain values in all the samples follow a common linear relationship with global strain. The results indicate that the type-B PLC band strain is independent of solute content at given strain rate.     

Disrupting the flow: How brief silences in group conversations affect social needs

We all know the awkward feeling when a conversation is disrupted by a brief silence. This paper studies why such moments can be unsettling. We suggest that silences are particularly disturbing if they disrupt the conversational flow. In two experiments we examined the effects of a single brief instance of silence on social needs, perceived consensus, emotions, and rejection. Study 1 demonstrated that fluent conversations are associated with feelings of belonging, self-esteem, and social validation. If a brief silence disrupts this fluency, negative emotions and feelings of rejection arise. Study 2 replicated these effects in a more realistic setting, and showed that the effects of a brief silence are considerable despite participants' unawareness of the silence. Together, results show that conversational flow induces a sense of belonging and positive self-esteem. Moreover, this research suggests an implicit route to social validation, in which consensus is inferred from fluent group conversation.     

Impairments in tactile search following superior parietal damage

The superior parietal cortex is critical for the control of visually guided actions. Research suggests that visual stimuli relevant to actions are preferentially processed when they are in peripersonal space. One recent study demonstrated that visually guided movements towards the body were more impaired in a patient with damage to superior parietal cortex. Whereas past studies have explored disordered movement in optic ataxic patients, there has been less exploration of space perception in terms of search capacity in this population. In addition, there is some debate concerning the relationship between deficits of visuomotor control and impaired attention/perception in optic ataxia. Given that the dorsal stream has been implicated in the spatial processing of stimuli in peripersonal space, and damage to this region is known to cause optic ataxia, we felt that further investigation was warranted. We examined tactile search behavior in the fronto-parallel and radial planes in a patient with right superior parietal damage and optic ataxia. We used a pegboard with removable cylindrical pegs that allowed for the reorganization of targets between trials. To better characterize three-dimensional search behavior, we included both horizontal and vertical search conditions. Results showed that the patient spent more time searching, was more accurate and revisited more targets in right versus left space. Interestingly, the patient spent the majority of her time specifically searching the lower right quadrant of the stimulus array. Further analysis revealed lower target detection rates along the outer borders of the pegboard on all sides. The search pattern observed here is unusual considering that all targets were within arm's reach. The present experiment demonstrates that damage to superior parietal cortex impairs tactile search and biases exploration towards lower right peripersonal space.