Suicidality in a Sample of Arctic Households

We investigated the association of suicidal ideation and behavior with depression, anxiety, and alcohol abuse in a Canadian Arctic Inuit community. Inuit (N = 111) from a random sample of households completed assessments of anxiety and depression, alcohol abuse, and suicidality. High rates of suicidal ideation within the past week (43.6%), and suicide attempts within last 6 months (30%), were reported. Ideation was more frequent among younger persons, whereas those favoring local native language were less likely to report a wish to die. Higher overall suicidality scores were associated with higher anxiety, and alcohol abuse, but not with depression or gender. Implications for future research are discussed.     

The cost of thinking about false beliefs: evidence from adults' performance on a non-inferential theory of mind task

Much of what we know about other people's beliefs comes non-inferentially from what people tell us. Developmental research suggests that 3-year-olds have difficulty processing such information: they suffer interference from their own knowledge of reality when told about someone's false belief (e.g., [Wellman, H. M., & Bartsch, K. (1988). Young children's reasoning about beliefs. Cognition, 30, 239-277.]). The current studies examined for the first time whether similar interference occurs in adult participants. In two experiments participants read sentences describing the real colour of an object and a man's false belief about the colour of the object, then judged the accuracy of a picture probe depicting either reality or the man's belief. Processing costs for picture probes depicting reality were consistently greater in this false belief condition than in a matched control condition in which the sentences described the real colour of one object and a man's unrelated belief about the colour of another object. A similar pattern was observed for picture probes depicting the man's belief in most cases. Processing costs were not sensitive to the time available for encoding the information presented in the sentences: costs were observed when participants read the sentences at their own pace (Experiment 1) or at a faster or a slower pace (Experiment 2). This suggests that adults' difficulty was not with encoding information about reality and a conflicting false belief, but with holding this information in mind and using it to inform a subsequent judgement.     

Effects of loading modes on densification efficiency of spark plasma sintering: sample study of zirconium carbide consolidation

Theoretical studies on the densification kinetics of the new spark plasma sinter-forging (SPS-forging) consolidation technique and of the regular SPS have been carried out based on the continuum theory of sintering. Both modelling and verifying experimental results indicate that the loading modes play important roles in the densification efficiency of SPS of porous ZrC specimens. Compared to regular SPS, SPS-forging is shown to be able to enhance the densification more significantly during later sintering stages. The derived analytical constitutive equations are utilised to evaluate the high-temperature creep parameters of ZrC under SPS conditions. SPS-forging and regular SPS setups are combined to form a new SPS hybrid loading mode with the purpose of reducing shape irregularity in the SPS-forged specimens. Loading control is imposed to secure the geometry as well as the densification of ZrC specimens during hybrid SPS process.     

From dating to mating and relating: Predictors of initial and long‐term outcomes of speed‐dating in a community sample

We studied initial and long‐term outcomes of speed‐dating over a period of 1 year in a community sample involving 382 participants aged 18–54 years. They were followed from their initial choices of dating partners up to later mating (sexual intercourse) and relating (romantic relationship). Using Social Relations Model analyses, we examined evolutionarily informed hypotheses on both individual and dyadic effects of participants' physical characteristics, personality, education and income on their dating, mating and relating. Both men and women based their choices mainly on the dating partners' physical attractiveness, and women additionally on men's sociosexuality, openness to experience, shyness, education and income. Choosiness increased with age in men, decreased with age in women and was positively related to popularity among the other sex, but mainly for men. Partner similarity had only weak effects on dating success. The chance for mating with a speed‐dating partner was 6%, and was increased by men's short‐term mating interest; the chance for relating was 4%, and was increased by women's long‐term mating interest. Copyright © 2010 John Wiley & Sons, Ltd.     

Reliability of implicit self‐esteem measures revisited

This study investigated the internal consistencies and temporal stabilities of different implicit self‐esteem measures. Participants (N = 101) responded twice—with a time lag of 4 weeks—to five different tasks: the Implicit Association Test (IAT), the Brief Implicit Association Test (BIAT), the Affective Priming Task (APT), the Identification‐Extrinsic Affective Simon Task (ID‐EAST) and the Name‐Letter Task (NLT). As expected, the highest reliability coefficients were obtained for the self‐esteem IAT. Importantly, the internal consistencies and the temporal stabilities of the APT, the ID‐EAST, and the NLT were substantially improved by using material, structural, and analytic innovations. In particular, the use of the adaptive response‐window procedure for the APT, the computation of error scores for the ID‐EAST, and the computation of a double corrected scoring algorithm for the NLT yielded reliability coefficients comparable to those of the established IAT. Implications for the indirect assessment of self‐esteem are discussed. Copyright © 2010 John Wiley & Sons, Ltd.     

Fractal dynamics of heart beat interval fluctuations in corticotropin-releasing factor receptor subtype 2 deficient mice

Non-linear fractal analysis of cardiac interbeat time series was performed in corticotropin-releasing factor receptor subtype 2 (CRFR2) deficient mice. Heart rate dynamics in mice constitutes a self-similar, scale-invariant, random fractal process with persistent intrinsic long-range correlations and inverse power-law properties. We hypothesized that the sustained tachycardic response elicited by intraperitoneal (ip) injection of human/rat CRF (h/rCRF) is mediated by CRFR2. In wildtype control animals, heart rate was increased to about maximum levels (~ 750 bpm) while in CRFR2-deficient animals baseline values were retained (~ 580 bpm). The tachycardic response elicited by ip-application is mediated by CRFR2 and is interpreted to result from sympathetic stimulation. However, the functional integrity of CRFR2 would not present a prerequisite to maintaining the responsiveness and resiliency of cardiac control to external environmental perturbations experimentally induced by extrinsic ip-application of h/rCRF or under physiological conditions that may be associated with an increased peripheral release of CRF. Under stressful physiological conditions achieved by novelty exposure, CRFR2 is not involved in the cardiodynamic regulation to external short-term stress. While the hypothesis of involvement of CRFR2 in cardiac regulation upon pharmacological stimulation cannot be rejected, the present findings suggest that the mechanism of action is by sympathetic stimulation, but would not unambiguously allow to draw any conclusions as to the physiological role of CRFR2 in the control of cardiac dynamics.