Structure of a phase induced with Xe-ion irradiation-implantation in γ-TiAl

A phase transformation in γ-TiAl intermetallic alloy was found to be induced with 50keV Xe-ion irradiation-implantation at doses larger than 2.2 x 10¹⁸ ions m^-2 at room temperature. The structure and the chemical composition of the induced phase were investigated with high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The zones of the induced phase have sizes up to about several tens of nanometres. The phase has a hexagonal structure with a = 0.286 nm and c = 0.462nm. The crystallographic orientation relationship between the phase (P) and the gamma-TiAl matrix is (001)_P//(111)_γ and \[100]_P//[011]_γ. The \[Al]/[Ti] atomic composition ratio in the phase is analysed to be 56/44, slightly different from that of the matrix, 51/49. These results suggest that the induced phase is an Al solid solution of α-Ti alloy phase, which has different structural parameters and chemical composition from those of the reported phase. It is suggested that the size of the ions is important in the phase transformation.     

Electron spin resonance of hydrogenated amorphous silicon-carbon alloy films prepared by magnetron sputtering

Abstract

New electron spin resonance (ESR) lines with g¹ = 2·0017 and g₂ and g₃ = 2·0006 have been found in the ESR spectra of as-deposited a-Si_1–x C_x:H films prepared by magnetron sputtering of silicon in the gas mixtures of methane and argon. Similarities between the observed spectra and those for the E′ centre in glassy SiO₂ are discussed.     

Emotional dynamics of soccer fans at winning and losing games

The purpose of the present study was to investigate the emotional reactions of fans of winning and losing teams at two professional soccer games. The participants were 187 male and 146 female Japanese soccer fans who provided biographical information and responded to a slightly modified state version of the Tension and Effort Stress Inventory (TESI; Svebak, Ursin, Endresen, Hjelmen, & Apter, 1991) pre-, mid- and post-game. Data from winning and losing fans were analysed using 3 × 2 independent groups ANOVAs for each of the pleasant emotions, unpleasant emotions, and tension stress/effort stress ratings with Bonferroni adjustment to control Type 1 error rates. When winning and losing fans’ responses were compared, most differences were found post-game, where losing fans scored significantly higher than winning fans on boredom, anger, sullenness, humiliation and resentment, and lower on relaxation. Also, levels of pleasant and unpleasant emotions changed significantly for losing fans, but (except for boredom) not for winning fans.     

Picture span test: Measuring visual working memory capacity involved in remembering and comprehension

The working memory system is assumed to operate with domain-specific (verbal and visuospatial) resources that support cognitive activities. However, in research on visuospatial working memory, an appropriate visual working memory task has not been established. For the present study, a novel task was developed: the picture span test (PST). This test requires memorizing parts of scene images while comprehending various scene situations simultaneously. Results of correlation analyses and a factor analysis among college students (n=52) validated that PST can predict visuospatial cognitive skills whereas a simple visual storage task and a verbal working memory task cannot. Furthermore, an error analysis indicated that inhibition is important for visuospatial working memory. Additionally, PST is considered to reflect individual differences in the visual working memory capacity. These findings suggest that the PST is appropriate for measuring visual working memory capacity and can elucidate its relationship to higher cognition.     

Effects of attention and external stimuli on duration estimation under aprospective paradigm

The study examined whether there are two independent cognitive factors affecting duration estimation. In two experiments, we manipulated simultaneously and independently two variables, namely, the level of attention to the lapse of time and the quantity of perceived changes, and examined their effects on duration estimation under a prospective paradigm. The duration was estimated to be longer when subjects attended to the lapse of time than when they attended to tasks during the target interval (Experiments 1 and 2). The characteristics of external stimuli irrelevant to the tasks, namely, the rate of presentation of sounds (Experiment 1) and the velocity of moving dots (Experiment 2), affected duration estimation, even though the attention level was little changed by these stimuli. These findings suggest that there are at least two independent cognitive factors that affect duration estimation.     

PACAP centrally mediates emotional stress-induced corticosterone responses in mice

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic neuropeptide widely distributed in the nervous system. Recently, PACAP was shown to be involved in restraint stress-induced corticosterone release and concomitant expression of the genes involved in hypothalamic-pituitary-adrenal (HPA) axis activation. Therefore, in this study, we have addressed the types of stressors and the levels of the HPA axis in which PACAP signaling is involved using mice lacking PACAP (PACAP?/?). Among four different types of stressors, open-field exposure, cold exposure, ether inhalation, and restraint, the corticosterone response to open-field exposure and restraint, which are categorized as emotional stressors, but not the other two, was markedly attenuated in PACAP?/? mice. Peripheral administration of corticotropin releasing factor (CRF) or adrenocorticotropic hormone induced corticosterone increase similarly in PACAP?/? and wild-type mice. In addition, the restraint stress-induced c-Fos expression was significantly decreased in the paraventricular nucleus (PVN) and medial amygdala (MeA), but not the medial prefrontal cortex, in PACAP?/? mice. In the PVN of PACAP?/? mice, the stress-induced c-Fos expression was blunted in the CRF neurons. These results suggest that PACAP is critically involved in activation of the MeA and PVN CRF neurons to centrally regulate the HPA axis response to emotional stressors.     

Research Ethics in Japanese Higher Education: Faculty Attitudes and Cultural Mediation

Principles of research ethics, derived largely from Western philosophical thought, are spreading across the world of higher education. Since 2006 the Japanese Ministry of Education has required universities in Japan to establish codes of ethical conduct and ensure that procedures are in place to punish research misconduct. Drawing on semi-structured interviews with 13 academics in a research-intensive university in Japan, this paper considers how research ethics is interpreted in relation to their own practice. Interviewees articulated a range of ethical issues connected with data gathering and interpretation, applying for and using research funds, relationships with peers and research subjects, and the dissemination of results. The paper also explores the effect of personal values and cultural norms on the Japanese interpretation of research ethics identifying the impact in terms of the treatment of graduate research students and decision-making processes.     

The role of the prefrontal cortex in the go/no-go task in humans: a positron emission tomography study

To study the localization of response inhibition in the human brain, especially the role of the prefrontal cortex and laterality of its activation, we used positron emission tomography (PET) to measure regional cerebral blood flow in 11 right-handed participants while they performed a go/no-go and a simple control reaction-time task. In the control task, the participants responded to a target stimulus following a cue stimulus. In the go/no-go task they were instructed to inhibit the required response if the target stimulus did not appear. These tasks were performed using each hand. The right prefrontal cortex was found to be significantly activated when the go/no-go task was compared with the control task, regardless of the responding hand. The results indicated that response inhibition per se may be controlled by the right prefrontal cortex regardless of response hand for right-handed participants.