Defect analysis of Fe3(Al1– x Si x ) alloys by positron-lifetime spectroscopy

The recovery behaviour of vacancy-type defects created at 1000°C in Fe₃(Al_{1– x} Si _x ) alloys has been investigated by positron-lifetime measurements in samples cooled to room temperature by water quenching, air quenching and furnace cooling. In addition, a set of samples was aged for one week at 520°C. After water quenching, measurements reveal a high concentration of thermal vacancies, and from the decrease of the average positron lifetime it is inferred that vacancy recovery is strongly composition-dependent. Greater decreases of the positron lifetime were found for Si-rich samples, suggesting diffusion enhancement as the Si concentration increases. For the Fe₃Al alloy, the retained vacancy concentration depends strongly on the cooling rate. This is related to atomic ordering and a rebuilding of the D0₃ structure.     

Solger and Hegel: Negation and Privation

Abstract

This paper has two related goals. Firstly, after briefly clarifying the theoretical core of Solger’s thought, it will analyse his metaphysics from Hegel’s point of view, emphasizing that sacrifice is, for Solger, the fundamental structure of the relationship between the finite and the Infinite. Secondly, it will investigate the main reasons behind Hegel’s criticism of Solger, showing that they have different conceptions of privation and negation and concluding that Solger and Hegel have different aims. Hegel’s aim consists in recomposing the unity of finite and infinite, whereas Solger’s thought is structured on the rupture between these two.     

The Spanish version of the Wisconsin Personality Disorders Inventory-IV (WISPI-IV): tests of validity and reliability

Personality disorders (PD) are a prevalent class of mental disorders that interfere with functioning and cause subjective distress while increasing the intensity and duration of Axis I clinical syndromes, and therefore assessing PD is important even when PDs are not the focus of treatment. The purpose of these studies was to develop and test a new Spanish version of a self-report measure of PD, the Wisconsin Personality Inventory-IV (WISPI-IV) that would be psychometrically equivalent to the English version while also maintaining the same interpersonal content, which is based on Benjamin's analysis of the PD criteria using her Structural Analysis of Social Behavior (SASB) model (1974). Study 1 participants completed the WISPI-IV twice over a two-week interval. For Study 2, participants from two sites in Spain and one site in Argentina completed Spanish versions of the WISPI-IV and other personality measures. SASB-analysis of the translated items showed high correspondence between the interpersonal content of the English version and the Spanish version demonstrating theoretical validation in relation to other PD measures. The Spanish WISPI-IV showed satisfactory reliability based on test-retest correlations and alphas for internal consistency. Study 2 showed the Spanish WISPI-IV had good convergent validity with the Spanish versions of the IIP and SCID-II and performed similarly to the English versions of these measures. Our goal in translating the WISPI-IV was to extend this measure to Spanish-speakers in language that would be understood by different Hispanic sub-groups, however research team members and subjects had a variety of suggestions for changes in item wording. This reflects the difficulty with creating a "neutral" Spanish version of any assessment given regional differences.     

Asymmetry in resting intracortical activity as a buffer to social threat

Social rejection can create powerful changes in people's brains and bodies. In the study reported here, we examined brain-based individual differences associated with buffering against cardiovascular threat responses to social rejection. Using EEG source-localization techniques, we examined differences in intracortical asymmetry. We predicted that individuals with greater left relative to right dorsolateral prefrontal activity would show a more approach-motivated response to social rejection. Eighty-four female participants were randomly assigned to one of three stressful situations: social rejection, social evaluation without rejection, or self-evaluation. Among participants assigned to the social-rejection condition, greater left relative to right prefrontal intracortical activity at baseline was associated with more adaptive cardiovascular profiles and more self-reported approach-oriented emotions. Participants in the other conditions did not show these relationships. Our data are the first to show that social context matters when attempting to link individual differences in cortical asymmetry with approach-related cardiovascular and emotional outcomes.     

Stability of the Spanish version of the five-item Francis Scale of Attitude toward Christianity

The aim of this study was to establish test-retest reliability of a Spanish version of the Francis Scale of Attitude toward Christianity (Campo-Arias, Oviedo, & Cogollo, 2009) among adolescent students in Cartagena, Colombia. A group of ninth grade students from two public schools in Colombia (N = 157) completed the five-item scale. Cronbach's alphas were .74 and .76 in the first and second administrations, respectively. Both Pearson's rho and intra-class correlation coefficient were .69. A Spanish translation of the 5-item scale had consistent stability over four weeks.     

Aversive experiences are associated with a rapid and transient activation of ERKs in the rat hippocampus.

The extracellular signal-regulated kinases (ERKs) family of mitogen-activated protein kinases (MAPKs) has been shown to participate in memory formation. We recently found that a hippocampal ERK/MAPK cascade is required for memory formation of an inhibitory avoidance training in rats. Here we reported that this learning task is accompanied by a rapid increase in the phosphorylation of hippocampal p44 MAPK. A single mild foot shock produced a similar effect and three consecutive foot shocks provoked the activation of both p44 and p42 MAPKs. In contrast, a brief exposure to the training box or the habituation to an open field did not alter hippocampal ERK/MAPK levels. Together, these findings indicate that aversive behavioral experiences induced a rapid and transient activation of ERK/MAPKs in the hippocampus.     

The role of informal social support in needs assessment: proposal and application of a model to assess immigrants' needs in the south of Spain

Needs assessment models have been generally focused on the identification and prioritization of needs, analysing formal resources available in the community as possible solutions for existing problems. These kinds of models have assumed that formal services are the primary source of support for individuals in need. However, a great deal of the investigations in the field of Social Psychology have shown that the main source of help and support when facing a problem is not formal organizations, but people's own informal networks. In this article, we therefore propose a needs assessment model that emphasizes the importance of analysing both formal and informal social resources. The application of this model to assess Moroccan immigrants' needs in the south of Spain shows the anticipated low level of utilization of formal services and programmes, one that contrasts with the high use of informal networks as an essential source of social support for this group of immigrants. These results reveal the limitations of traditional needs assessment models, and the importance of incorporating the analysis of informal social support as a key resource for need satisfaction, particularly in the case of immigrant populations. Copyright © 2004 John Wiley & Sons, Ltd.     

The importance of body satisfaction to physical self‐concept and body mass index in Spanish adolescents

This research examines the association between measured body mass index (BMI) and the perception of BMI by young students. Moreover, this research tests the importance of BMI and self‐concept, in order to predict body dissatisfaction in high school students. The sample consisted of 2087 individuals from different high schools in Extremadura, Spain, both males (n = 1046) and females (n = 1041), ranging in age from 15 to 17 years old (M = 15.42; SD = 0.86). Initially, participants' BMIs were assessed through anthropometry. Later, all individuals were asked about their weight and height, and their self‐reported BMI was calculated. Participants also answered a questionnaire about their perception of self‐concept, as well as completed a test about body image perception using Stunkard images. Outcomes revealed that factors concerning self‐concept and perceived BMI explained body dissatisfaction. Finally, results are discussed with the aim of improving knowledge in body dissatisfaction context.     

ERK1/2 activation is necessary for BDNF to increase dendritic spine density in hippocampal CA1 pyramidal neurons

Brain-derived neurotrophic factor (BDNF) is a potent modulator of synaptic transmission and plasticity in the CNS, acting both pre- and postsynaptically. We demonstrated recently that BDNF/TrkB signaling increases dendritic spine density in hippocampal CA1 pyramidal neurons. Here, we tested whether activation of the prominent ERK (MAPK) signaling pathway was responsible for BDNF's effects on spine growth. Slice cultures were transfected with enhanced yellow fluorescent protein (eYFP) by particle-mediated gene transfer, and CA1 pyramidal neurons were imaged by laser-scanning confocal microscopy. We confirmed that BDNF (24 h) increases spine density in apical dendrites of CA1 neurons. The MEK (ERK kinase) inhibitors PD98059 and U0126 completely prevented the increase in spine density induced by BDNF, without having an effect on spine density by themselves. In contrast to its actions on cortical pyramidal neurons, BDNF had minor and rather localized effects on dendritic complexity in hippocampal pyramidal neurons, increasing the total length, but not the branching of apical dendrites within CA1 stratum radiatum, without affecting basal dendrites in stratum oriens. Our results support the hypothesis that the ERK-signaling pathway not only mediates long-term synaptic plasticity and hippocampal-dependent learning, but it is also involved in the structural remodeling of excitatory spine synapses triggered by neurotrophins.     

Stability of mood states and biochemistry across pregnancy

Four hundred and thirty pregnant women were recruited during their second trimester of pregnancy (M=20 weeks). They were designated depressed (N=172) or nondepressed (N=258) on the Structured Clinical Interview of Depression (SCID) and the Center for Epidemiological Studies Depression scale (CES-D). They were given a second assessment when they were approximately 32 weeks gestational age. At both assessments they were given self-report measures (CES-D, the State Anxiety Inventory, and the State Anger Inventory) and provided urine samples for assays of cortisol, catecholamines (norepinephrine, epinephrine and dopamine) and serotonin. They were also given the VITAS scale for lower back pain and leg pain and a sleep disturbance scale. The stability of mood states and biochemistry across pregnancy (20 and 32 weeks) were assessed inasmuch as mood states, and biochemistry have been noted to predict prematurity and low birthweight. Significant correlations were noted for all variables except serotonin. Relationships between mood states and biochemistry were also noted but only between cortisol and depression, cortisol and anxiety, and epinephrine and anxiety. Significant stability was noted between the 20-week measures and the 32-week measures including depression, anxiety, anger, and cortisol. These were, in turn, correlated with each other and with, low back pain, leg pain, and sleep disturbance. These data suggest the stability of mood states and cortisol across pregnancy.