Thermal expansion of icosahedral Al-Pd-Mn and decagonal Al-Cu-Co quasicrystals

Thermal expansion measurements have been performed by X-ray diffractometry on icosahedral Al-Pd-Mn (i-(Al-Pd-Mn)) in the temperature range between 10 and 700K and on decagonal Al-Cu-Co (d-(Al-Cu-Co)) in the range between 100 and 750K. The linear thermal expansion coefficient alpha(T) of i-(Al-Pd-Mn) is about half of that for the pure aluminium phase at room temperature and does not show a negative thermal expansion at low temperatures. The degree of anisotropy in the thermal expansion of d-(Al-Cu-Co) is small; the ratio of the average alpha between the tenfold periodic direction and a quasiperiodic direction perpendicular to it is 0:93 +/- 0:05. The Gruneisen parameter gamma(T) has been evaluated from the measured alpha(T). gamma for d-(Al-CuCo) is almost isotropic, similar to alpha. The gamma values for the two phases lie in the range between 1.5 and 1.8, which are comparable with those for conventional metallic crystals. They are almost constant over the temperature range studied.     

New stable icosahedral phases in Al-Pd-Ru and Al-Pd-Os systems

We have found stable icosahedral (i) phases in alloys with nominal compositions around Al 72 Pd 17 Ru 11 and Al 72 Pd 17 Os 11 . They display very sharp X-ray diffraction peaks, indicating high structural order as in other Al-based i-phases such as i-(Al-Pd-TM) (transition metal TM = Mn or Re) and i-(Al-Cu-TM) (TM =Fe, Ru or Os). The i phases are formed via peritectic reaction and, upon heating, they transform into a mixture of a liquid and the 1/0 cubic approximant phase. The electrical resistivity of the i phases was measured in a wide temperature range from 14K to above their melting points and a reversible change of the resistivity across the melting point has been observed in situ for the first time.     

The role of learning experience on the perceptual organization of Chinese characters

The effect of learning experience on the perceived graphemic similarity of Chinese characters was examined by comparing results of the constrained (Experiment 1) and unconstrained (Experiment 2) shape-sorting tasks obtained from various groups of participants with different learning experiences and ages. The results from hierarchical cluster analysis showed that both Taiwanese and Japanese undergraduates classified characters in relation to their configurational structures, whereas American undergraduates, Taiwanese illiterate adults, and kindergartners categorized characters based on strokes or components. Although a trend of developmental changes from local details to more globally defined patterns was found, the identification of structure as consistently perceived by skilled readers has to be nourished by learning experience and cannot be obtained solely through maturation.     

The electrophysiology of introspection

To study whether the distinction between introspective and non-introspective states of mind is an empirical reality or merely a conceptual distinction, we measured event-related potentials (ERPs) elicited in introspective and non-introspective instruction conditions while the observers were trying to detect the presence of a masked stimulus. The ERPs indicated measurable differences related to introspection in both preconscious and conscious processes. Our data support the hypothesis that introspective states empirically differ from non-introspective states.     

Preliminary study of psychological factors affecting clinic attendance and glycemic control of Japanese patients with type 2 diabetes mellitus

We studied 50 Japanese patients who were first diagnosed with type 2 diabetes mellitus. Psychological functioning was assessed by using the Rorschach test and the Yatabe-Guilford Personality test. Analysis indicated that patients who discontinued clinic attendance during the 2-yr. study period had more depression, lower general activity and less extraversion, more negative self-attitudes, and more concern about being helpless than those who continued having regular followups. This study also found that patients who had worse glycemic control 2 yr. after being first diagnosed reported more inferiority feelings, lower general activity, more need for closeness to others, and more emotional demands than those who had better glycemic control. In conclusion, understanding the psychological functioning would be helpful in the management of Japanese patients with type 2 diabetes mellitus.     

A structural model of acculturation and mental health status among Chinese Americans

This study examined the role of acculturation and its direct and indirect impact on depressive symptom severity through various correlates, including socioeconomic status (SES), stress, social support, personality negativity, and physical health perception. Using structural equation modeling, the proposed model was tested with 983 employed Chinese Americans from a representative community sample, the majority of whom were immigrants. The results demonstrated that acculturation, correlated with SES, contributed to depressive symptom severity only through indirect pathways. Higher acculturation was found associated with higher stress that in turn contributed to more elevated depressive symptoms. On the other hand, higher acculturation was also found strongly correlated with higher SES, which was associated with lower depressive symptoms directly or indirectly through several mediators. Better support, lower personality negativity, better health perception, and lower stress were found mediating the relationship between higher SES and lower depressive symptom severity. The simultaneous multigroup analysis showed that the final model was comparable for both men and women with very few differences.     

Interhemispheric categorization of pictures and words

Earlier studies suggest that interhemispheric processing increases the processing power of the brain in cognitively complex tasks as it allows the brain to divide the processing load between the hemispheres. We report two experiments suggesting that this finding does not generalize to word-picture pairs: they are processed at least as efficiently when processed by a single hemisphere as compared to processing occurring between the two hemispheres. We examined whether dividing the stimuli between the visual fields/hemispheres would be more advantageous than unilateral stimulus displays in the semantic categorization of simultaneously presented pictures, words, and word-picture pairs. The results revealed that within-domain stimuli (semantically related picture pairs or word pairs) were categorized faster in bilateral than in unilateral displays, whereas cross-domain stimuli (word-picture pairs) were not categorized faster in bilateral than in unilateral displays. It is suggested that interhemispheric sharing of word-picture stimuli is not advantageous as compared to unilateral processing conditions because words and pictures use different access routes, and therefore, it may be possible to process in parallel simultaneously displayed word-picture stimuli within a single hemisphere.     

Treatment of a biracial child with schizophreniform disorder: cultural formulation

Over the past several years, the field of psychiatry has shown a higher level of cultural sensitivity and an increasing interest in the role of cultural factors in mental health. This has been notably reflected in the incorporation of cultural considerations, such as an outline for cultural formulation and a glossary of culture-bound syndromes, in the Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV; American Psychiatric Association, 1994). This case report is illustrative of the significance of considering cultural elements in diagnosing and treating a psychiatric disorder. It is also the first-known detailed case report on fakamahaki, a culture-bound syndrome from the Kingdom of Tonga. The syndrome is described in a child from the perspective of a child psychiatry fellow. To serve as a teaching case for clinicians in training as well as those in practice, the DSM-IV outline for cultural formulation has been used. This case can be helpful in educating others in the mental health field about the utility of a more comprehensive approach to understanding clients in contrast to the growing trend of very focused approaches.     

Parental Physical Illnesses and Their Association with Subsequent Externalizing and Internalizing Symptoms in Children

Journal of Child and Family Studies - Parental physical illnesses can be stressful for children. We estimated the prevalence of children who experience parental physical illnesses, and whether...     

Latent timing in human conditioned avoidance

Four experiments explored signal timing in human conditioned avoidance. Participants received discrimination training with different duration signals that announced the outcome (S+) or not (S-). Temporal discrimination and superposition of performance to S+ signals of different length (3, 6, or 9 s) was found both in within-subjects (Experiment 1a) and between-subjects (Experiment 1b) designs. S- signals also produced a temporal discrimination and superposition effect during a single test trial conducted after the meaning of the signals was reversed through instructions. Experiments 2a and 2b replicated these results in a situation in which (a) the durations of the S+ and S- signals were different (4.5 or 9 s) to prevent any temporal generalization between them (Experiment 2a), and (b) only S- signals were presented during training, precluding developing of inhibition to S- (Experiment 2b). These results show that participants time both S+ and S- signals in human conditioned avoidance, and they further suggest that the timing of a cue is independent of reinforcement.