Ventajas e inconvenientes del uso del preservativo con una pareja afectiva heterosexual

Se analiza la validez de constructo y la consistencia interna de un cuestionario sobre ventajas e inconvenientes del uso del preservativo con una pareja afectiva heterosexual, así como su capacidad para predecir el uso del preservativo en el pasado y la intención de uso en los próximos tres meses. Participan en el estudio 1711 estudiantes universitarios (46.3% varones y 60% menores de 21 años) elegidos mediante muestreo de conveniencia. Se emplea un diseño transversal y los datos se recogen mediante autoinforme voluntario y anónimo. Los resultados muestran que la consistencia interna del cuestionario es equiparable a la de otros instrumentos semejantes (alfas de Cronbach en escala de ventajas: .605 y en escala de inconvenientes: .725). Tanto las ventajas como los inconvenientes del uso del preservativo predicen significativamente su uso sistemático en el pasado, con un mayor peso de las ventajas. Entre los jóvenes que no lo han utilizado siempre, y únicamente en los varones, las ventajas predicen la intención de uso en los próximos tres meses. Los resultados apoyan la realización de programas preventivos que destaquen los beneficios derivados del uso de preservativo y, así mismo, reduzcan las percepciones negativas asociadas a su empleo, con una atención preferente a los primeros

Structural Validity of the Wechsler Intelligence Scale for Children (WISC-IV) in a French-speaking Swiss sample

The Wechsler Intelligence Scale for Children-fourth edition (i.e. WISC-IV) recognizes a four-factor scoring structure in addition to the Full Scale IQ (FSIQ) score: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI) indices. However, several authors suggested that models based on the Cattell-Horn-Carroll (CHC) theory with 5 or 6 factors provided a better fit to the data than does the current four-factor solution. By comparing the current four-factor structure to CHC-based models, this research aimed to investigate the factorial structure and the constructs underlying the WISC-IV subtest scores with French-speaking Swiss children (N = 249). To deal with this goal, confirmatory factor analyses (CFAs) were conducted. Results showed that a CHC-based model with five factors better fitted the French-Swiss data than did the current WISC-IV scoring structure. All together, these results support the hypothesis of the appropriateness of the CHC model with French-speaking children.

Creencias sesgadas respecto al grado de "dureza" de algunas drogas en estudiantes universitarios

El objetivo de esta investigación es evaluar las creencias de los estudiantes universitarios respecto a la dureza de diez drogas: anfetaminas, café, heroína, barbitúricos, marihuana, ansiolíticos, tabaco, alcohol, cocaína y té. Ciento cincuenta y cinco estudiantes de Psicología debían indicar si creían que estas sustancias eran o no drogas duras. Los resultados indican que aunque existe consenso a la hora de clasificar como drogas duras a la heroína y la cocaína y como drogas blandas al tabaco, el café y el té, no existe acuerdo respecto a la clasificación de las otras sustancias. Asimismo se observa que aunque la OMS clasifica el alcohol como una droga altamente peligrosa, menos de la mitad de sujetos lo consideran una droga dura. En general los sujetos tienden a considerar las drogas legales como menos duras independientemente de si los efectos nocivos para la salud. Estos resultados adquieren relevancia cuando lo que se pone en juego es la fiabilidad y validez de los datos obtenidos en diferentes investigaciones que utilizan habitualmente esos conceptos

Validación chilena del cuestionario de evaluación de apego en el adulto CAMIR

El objetivo de esta investigación fue examinar la confiabilidad y validez del instrumento de evaluación de apego en el adulto, "Cartes: Modèles Individuels de Relation (CAMIR), en la realidad sociocultural chilena. Este instrumento, basado en la teoría del apego, es un cuestionario de auto-reporte que evalúa los modelos operativos internos en adultos y otras escalas relacionadas al apego. Los participantes fueron 578 sujetos, 204 hombres y 374 mujeres, con edades entre 14 y 80 años. Los sujetos completaron el CAMIR y medidas de vínculo y sintomatología actual, a través del Parental Bonding Instrument (PBI) and Outcome Questionnaire OQ-45.2. A través del análisis estadístico de los resultados se evaluaron las características psicométricas del test y de analiz ó la posibilidad de generar normas locales para la prueba. Los resultados confirmaron que el CAMIR es un instrumento confiable y válido en la evaluación de los modelos internos de relación en adultos. This study was designed to estimate the validity and reliability of the "Cartes: Modèles Individuels de Relation (CAMIR), in Chile. This inventory, based on attachment's theory, it's a auto-questionnaire evaluates the working models in adults and other scales relating to attachment. Participants were 578 individuals, 204 males and 374 females, 14 a 80 years old. Individuals completed the CAMIR and measures of bond and actual symptoms, with the Parental Bonding Instrument (PBI) and Outcome Questionnaire OQ-45.2. The general norms were obtained according to a statistical analysis of the results and to an evaluation of the psychometric characteristics of the test. The results confirmed that the psychometric characteristics of the CAMIR make it a reliable and valid tool to assess working models in adults.

Validation of order rank scales based on compositional data analysis: a proposal

Usually, psychometricians apply classical factorial analysis to evaluate construct validity of order rankscales. Nevertheless, these scales have particular characteristics that must be taken into account: totalscores and rank are highly relevant

Parental influences on pathogen resistance in brown trout embryos and effects of outcrossing within a river network.

Phenotypic plasticity can increase tolerance to heterogeneous environments but the elevations and slopes of reaction norms are often population specific. Disruption of locally adapted reaction norms through outcrossing can lower individual viability. Here, we sampled five genetically distinct populations of brown trout (Salmo trutta) from within a river network, crossed them in a full-factorial design, and challenged the embryos with the opportunistic pathogen Pseudomonas fluorescens. By virtue of our design, we were able to disentangle effects of genetic crossing distance from sire and dam effects on early life-history traits. While pathogen infection did not increase mortality, it was associated with delayed hatching of smaller larvae with reduced yolk sac reserves. We found no evidence of a relationship between genetic distance (W, FST) and the expression of early-life history traits. Moreover, hybrids did not differ in phenotypic means or reaction norms in comparison to offspring from within-population crosses. Heritable variation in early life-history traits was found to remain stable across the control and pathogen environments. Our findings show that outcrossing within a rather narrow geographical scale can have neutral effects on F1 hybrid viability at the embryonic stage, i.e. at a stage when environmental and genetic effects on phenotypes are usually large.

Validation of a new tool to assess health-related quality of life in psoriasis: the PSO-LIFE questionnaire.

BACKGROUND Several questionnaires have been used to measure health related quality of life (HRQoL) in patients with psoriasis, few have been adapted for use in Spain; none of them was developed specifically for the Spanish population. The purpose of the study was to validate and assess the sensitivity to change of a new questionnaire to measure HRQOL in patients with psoriasis (PSO-LIFE). METHODS Observational, prospective, multicenter study performed in centers around Spain. Patients with active or inactive psoriasis completed the PSO-LIFE together with other Dermatology Quality of Life Index (DLQI) and Psoriasis Disability Index (PDI). A control group of patients with urticaria or atopic dermatitis was also included. Internal consistency and test-retest reliability of the PSO-LIFE were assessed by calculating Cronbach's alpha and Intraclass Correlation Coefficient (ICC). Validity was assessed by examining factorial structure, the capacity to discriminate between groups, and correlations with other measures. Sensitivity to change was measured using effect sizes. RESULTS The final sample included for analysis consisted of 304 patients and 56 controls. Mean (SD) age of psoriasis patients was 45.3 (14.5) years compared to 38.8 (14) years for controls (p < 0.01). Cronbach's alpha for the PSO-LIFE was 0.95 and test-retest reliability using the ICC was 0.98. Factor analysis showed the questionnaire to be unidimensional. Mean (SD) PSO-LIFE scores differed between patients with psoriasis and controls (64.9 [22.5] vs 69.4 [17.3]; p < 0.05), between those with active and inactive disease (57.4 [20.4] vs 76.4 [20.6]; p < 0.01), and between those with visible and non-visible lesions (63.0 [21.9] vs. 74.8 [23.9]; p < 0.01). The correlation between PSO-LIFE and PASI scores was moderate (r = -0.43) while correlations with DLQI and PDI dimensions ranged from moderate to high (between 0.4 and 0.8). Effect size on the PSO-LIFE in patients reporting 'much improved' health status at study completion was 1.01 (large effect size). CONCLUSIONS The present results provide substantial support for the reliability, validity, and responsiveness of the PSO-LIFE questionnaire in the population for which it was designed.

Intra- and intersexual selection and their potential consequences on fitness-relevant traits in several fish species

Résumé : Les mécanismes de sélection sexuelle, en particulier la compétition entre mâles (sélection inter-sexuelle) et le choix des femelles (sélection intra-sexuelle), peuvent fortement influencer le succès reproducteur d'un individu, c'est-à-dire son nombre de descendants. On observe ainsi que les mâles dominants et les mâles élaborant des caractères sexuels secondaires marqués ont un succès reproducteur élevé. Toutefois, le succès reproducteur ne suffit pas pour garantir une contribution génétique élevée, parce que la fitness dépend également de la performance des descendants (c'est-à-dire de leur survie et de leur propre succès reproducteur). Si cette performance dépend en partie des gènes paternels, les males ont un avantage certain à signaler leur qualité aux femelles afin d'atteindre des taux de reproduction élevé. Ce mécanisme de signalisation est connu sous le nom de 'good genes hypothesis', toutefois très peu d'études ont clairement démontré le lien entre la qualité génétique des individus et la signalisation. De plus, la performance des descendants peut aussi dépendre des effets génétiques de compatibilité entre mâles et femelles ('compatible genes'). C'est-à-dire que certains allèles paternels n'apporteraient un avantage aux descendants qu'en combinaison avec certains allèles maternels. Nous avons déterminé, durant la période de reproduction, le statut de dominance des mâles pour deux espèces de poissons d'eau douce : la truite (Salmo trotta) et le vairon (Phoxinus phoxinus), puis nous avons évalué la relation entre le succès reproducteur et le statut de dominance et/ou la quantité de signalisation des caractères sexuels secondaires. Nous avons également fécondés artificiellement des oeufs de truites et de corégones (Coregonus palaea), en croisant chaque mâle avec chaque femelle (full-factorial breeding design). Ce type de design autorise la quantification précise des effets génétiques et permet de séparer les effets de 'good genes' et de 'compatible genes'. Cela a été fait sous différentes intensités de stress bactérien, ainsi que dans des conditions naturelles, et nous avons pu ainsi tester si certains indicateurs de qualité génétique des mâles ('good genes') étaient liés a) à la dominance et/ou b) à l'expression des caractères sexuels secondaires des mâles comme l'intensité mélanique ou la taille des tubercules sexuels. En outre, nous cherchons à savoir si la survie des descendants est liée à certaines combinaison des gènes du complexe d'histocompatibilité majeur (MHC) et/ou à la parenté génétique des parents, les deux traits étant soupçonnés d'avoir des influences génétique de compatibilité (`compatible genes') à la performance des descendants. Nous avons constaté que la dominance des mâles est directement liée à la taille et au poids des mâles (truites, vairons), mais également aux caractères sexuels secondaires (tubercules). De plus, les mâles vairons dominant ont eu un succès de fécondation plus élevés que les mâles subordonnés. Nous montrons que les truites et corégones mâles diffèrent dans leur qualité génétique, qui a été mesurée avéc la survie embryonnaire, le temps avant l'éclosion et enfin la croissance juvénile. Contrairement aux prédictions, la dominance (ou les traits indicatifs de dominance) n'était liée à la qualité génétique, dans aucun des traitements, et ne fonctionne donc pas comme indicateur de qualité. Par contre, la qualité génétique était liée aux caractères sexuels secondaires, particulièrement par la teinte mélanique chez les truites. Les embryons de truites issus de pères sombres survivaient mieux que ceux issus de pères clairs dans des environnements difficiles, de plus leur croissance était plus élevée lors de leur première année dans des conditions naturelles. La taille des juvéniles lors de leur première année est un trait important lié au succès dans la compétition pour des ressources telles qu'abri ou nourriture. De plus, les femelles truites peuvent augmenter la survie de leurs descendants en choisissant des mâles selon leur type de MHC ou selon leur degré de parenté. En outre, chez les corégones, la morphologie des tubercules sexuels ne semble pas signaler la qualité génétique. Nous avons également remarqué que l'exposition à des pathogènes non-létaux pouvait influencer la performance des alevins à court et long terme, probablement en affaiblissant leur système immunitaire. Cette thèse montre que les mâles diffèrent dans leur qualité génétique et que différents mécanismes de sélection inter- ou intra-sexuelle (par exemple la préférence pour des mâles sombres, pour des génotypes MHC ou pour des couples avec degré de parenté basse) pouvait avoir un effet positif sur la qualité des descendants, bien que cet effet génétique pouvait changer au cours du temps et entre différents environnements. Contrairement à nos attentes, le résultat de la compétition intra-sexuelle (la hiérarchie de dominance entre mâles) n'était pas lié à la qualité génétique individuelle ('good genes'). Dans ce sens, ce travail permet également de contribuer à l'explication du fait que la sélection sexuelle, de par sa forte sélection directionnelle, ne conduit pas à la diminution de la variance génétique, mais plutôt à la maintenance du polymorphisme génétique. Summary : Sexual selection mechanisms, especially male-male competition (inteasexual selection) and female mate choice (inteasexual selection), can strongly influence individual mating success, often resulting in dominant males and males with elaborate secondary sexual characters having higher fertilisation success. However, siring a high number of offspring alone does not guarantee high individual fitness, as fitness does also strongly depend on offspring performance (i.e. survival, fecundity). If this superiority in offspring performance depends on paternally inherited genes, the fathers are expected to signal this potential indirect benefit to females in order to attain high mating rates. This mechanism is also known as the 'good genes' hypothesis of sexual selection but until now most studies failed to conclusively show the relation of an individual genetic quality and its potential signalling traits. Further, offspring performance could also depend on compatible gene effects. These are alleles that increase offspring performance only in combination with other specific alleles. We first determined male dominance status from intrasexual competition during mating season for brown trout (Salmo trutta) and European minnows (Phoxinus phoxinus). For minnows we additionally checked if dominance and/or secondary sexual traits were linked to fertilisation success. Further, we artificially fertilised brown trout and alpine whitefish (Coregonus palaea) eggs, following full factorial breeding designs, enabling to properly measure `good gene' and `compatible gene' effects on offspring performance. This was done under different intensities of natural stressors, as well as under natural conditions. This procedure allowed us to test if the obtained male genetic quality measures (good genes effects) were indicated by a) dominance or lay traits linked to dominance and/or by b) secondary sexual characteristics such as melanin-based male skin darkness or breeding tubercles. Further, we investigated if offspring survival was linked to the MHC (major histocompatibility complex) gene combinations and/or to the parental genetic relatedness, as both traits were shown to have 'compatible gene' effects that may influence offspring performance. We found that male dominance in intrasexual competition was positively linked to body size, body weight (brown trout, minnows) but also to elaborate secondary sexual characteristics (breeding tubercles in minnows). Further, dominant minnow males did have an increased fertilisation success compared to subordinate ones. We show that brown trout and whitefish males do usually differ in their genetic quality, which was measured as embryo survival, hatching timing and finally as juvenile growth. Contrary to prediction male dominance or dominance indicating traits do not function as a quality signal as they were not linked to genetic quality. This result was constant when measuring genetic quality under different levels of natural stressors and under natural conditions (brown trout). On the other hand genetic quality seemed to be indicated by secondary sexual characteristics, specifically by melanin-based skin darkness in brown trout as brown trout embryos sired by darker fathers had increased survival rates when raised under harsh conditions and. they grew larger as juveniles after one year of growth in a natural stream, which is an important trait influencing success of juveniles in competition for hidings, food and other resources. Furthermore, brown trout females may increase the survival of their embryos when choosing males according to their MHC genotypes or to the general genetic relatedness between themselves and their potential mates. In whitefish on the other hand breeding tubercle morphology did not seem to signal genetic quality. Eventually, we saw that anon-lethal exposure to pathogens might influence short term and long term offspring performance probably by weakening an exposed individual's immune system. This thesis shows that males usually differ in their genetic quality and that different inter- or intrasexual selection mechanisms (e.g. mate selection favouring dark males, preference for MHC genotype combinations or for unrelated mates) may have strong positive effects on genetically dependent offspring performance but that such genetìc effects can change over time and environments. In contrast to our a priori expectations, the outcome of intrasexual selection, namely male dominance hierarchies, with dominant males often having high fertilisation success, was not linked to individual genetic quality (`good genes'). In this sense the present thesis may also be a helpful contribution to understand why sexual selection does not lead to rapid loss of genetic variation by strong directional selection but could even lead to the maintenance of genetic variation in natural populations.

Validation statistique et structurale du questionnaire analytique de diagnostic de la personnalité (Q.A.P.)

The French Analytical Questionnaire of diagnostic of the Personality (Q.A.P., 1996), who took over from the characterological questionnaire of Berger (1950), is a interesting one for psychologists and characterologists because this test is based on very coherent theoretical corpus. This questionnaire is divided in two parts, the first one consists of three factor or fundamental scales which allow to determine the characterological type of individuals, the second part is made of nine complementary scales allowing to determine more precisely the personality of the subjects. We have done a structural validation of that questionnaire using a large sample (n=865). Several factor analyses were conducted on both part of the test. We also made a reliability analysis of each scale using the alpha of Cronbach and a homogeneity analysis of each question. Thank to these analyses we were able to evalue that instrument and we were able to set up that the factorial structure of the test corresponds to the theoretical one developped by the french school of characterology. The Analytical Questionnaire of diagnostic of the Personnality is globaly reliable in particullary the fist part which is very consistent. The second part is less reliable, and this is partly on due to the correlations between the scales. We have also done a correlational analysis between the first part of the Q.A.P., the questionnaire of Berger and the Rapid Questionnaire of Diagnostic of the Personnality (Q.R.D.P., 1996). The Q.A.P. might be the more reliable one. Finally we have evaluated the impact of gender, age and profession on the factors of the Analytical Questionnaire of diagnostic of the Personnality.

Marital satisfaction: Psychometric properties of the PFB and comparison with the DAS

This study examines the French versions of two marital satisfaction scales: the Dyadic Adjustment Scale (DAS) and the Partnership Questionnaire (PFB). 127 couples, married or living together for at least 3 years, participated in this research and each partner responded individually to both scales. The analysis revealed high internal consistencies for both scales and most of the subscales. Concerning the DAS, the factorial structure did not replicate the theoretical structure. Moreover, the structure underlying this scale seems unstable across cultures. On the other hand, the structure of the PFB seems reliable and stable through cultures. The correlation between the DAS and the PFB is high (r=.80) and the three canonical correlation variates explain about 60% of the variance of both scales. Both scales are sensitive to demographic variables and couple characteristics. The agreement within couples is high. The PFB seems well suited to assess marital satisfaction for clinical and research purposes.

Planteamiento y optimización de experimentos analíticos

En el prosent projecte s'introduirà la teoria del disseny estadístic d'experiments i ens endinsarem amb més profunditat en els dissenys factorials complerts. Aquest tipus de dissenys, són d'aplicació en sistemes en els que es desitja estudiar la influència que tenen els k factors sobre una variable resposta. Els dissenys factorials complerts, són aquells en els que els k factors poden prendre diversos nivells, i es contemplen totes les posibles combinacions entre ells. Aquest projecte es centrarà més concretament en els dissenys factorials complerts 2, on el número 2 indica que cadascun els factors pren 2 nivells diferents. S'explicarà la teoria corresponent a aquests dissenys amb l'ajuda de diversos exemples, explicant des de un disseny factorial en el que s'estudia la influència de 2 factros (2), fins a un en el que s'estudia la influència de 4 factors (2). També s'ha introduït alguns mètodes que ens ajudaran a trobar models matemàtics que s'ajustin al sistema, i algunes metodologies d'optimització com la metodologia de superficie de resposta o el mètode simplex, per poder treure el màxim partit als nostres recursos. Una vegada introduïts tots aquests conceptes, es procedirà a realitzar un estudi i optimització d'una reacció química que consisteix en l'eliminació del coure d'una dissolució per a la posterior utilització d'aquesta dissolució en la industria per a l'extracció d'or i plata. El segon cas d'aplicació serà la realització de l'estudi i optimització del procés d'obtenció de biodièsel. En ambdós casos s'aplicarà un disseny factorial complet 2, però en cada un s'aplicarà una metodologia diferent per realitzar la optimització. Donat que aquest és un projecte purament centrat en el disseny d'experiments i en el tractament de les dades obtingudes, l'experimentació no ha sigut realitzada per nosaltres, sinó que la informació referent a la mateixa s'ha obtingut d'articles acadèmics realitzats per diferents universitats que han realitzat els estudis corresponents.

Intervenció educativa eficaç en justícia juvenil

La recerca presenta el resultat de la segona aplicació del Programa del Pensament Prosocial, Versió Curta per a Joves en una mostra de menors que han complert mesures judicials en un equip de Medi Obert de Lleida. Aquest programa cognitiu-conductual entrena en l’aprenentatge d’habilitats sociocognitives i valors que es requereixen per la competència social i s’ha aplicat amb èxit a joves infractors i adults de 14 països de tot el món a més de quaranta mil subjectes. La recerca aplica el programa utilitzant com a mètode un disseny pre-test i post-test amb grup de control. Dels resultats es destaca que l’aplicació del programa incorpora en la intervenció en medi obert un canvi important en el plantejament de treball, ja que els instruments estan específicament dissenyats per a menors que s’han mostrat més resistents a altres intervencions.

La utilització dels "serious games" en el tractament dels trastorns mentals : una revisió

Aquest article de revisió analitza l'ús que s'està fent dels anomenats "serious games" en el tractament dels trastorns mentals. La recerca efectuada a les bases de dades Medline i PsycINFO han donat com a resultat la localització de 537 articles que fan referència als "serious games" i als "computer games", dels quals 71 ho fan a la seva aplicació en l'àmbit de la salut i 14 a l'àmbit mes concret dels trastorns mentals. S'han trobat estudis que contemplen tractaments per l'esquizofrènia, el Trastorn per Dèficit d'Atenció i Hiperactivitat (TDAH), el Trastorn per Estrès Posttraumàtic (TEPT), l'autisme, el retard mental i les fòbies. Hi ha resultats encoratjadors en quan a l'eficàcia dels tractaments utilitzant jocs d'ordinador, realitat virtual i realitat augmentada, si bé degut a ser un camp de recerca molt jove es necessita replicar molts estudis per tal de donar validesa científica als resultats provisionals obtinguts.

Maternal and paternal contributions to pathogen resistance dependent on development stage in a whitefish (Salmonidae)

It is often assumed that maternal and paternal contributions to offspring phenotype change over the lifetime of an individual. However, studies on parental effects typically suffer from the problems that heritabilities and maternal environmental effects are difficult to separate, and that both may depend on environmental factors and developmental stage. In order to experimentally disentangle maternal from paternal contributions and the likely effects of developmental stage from ecological effects, we sampled a natural population of the whitefish Coregonus palaea, used gametes for full-factorial in vitro fertilizations, raised over 10000 of the resulting offspring singly at controlled conditions, and exposed them at different points during embryonic development to one of two strains of Pseudomonas fluorescens that differed in their virulence characteristics (only one caused mortality, while both delayed hatching and reduced growth). Vulnerability to infection increased markedly over embryo development. This change coincided with a distinct shift in the importance of maternal to additive genetic effects on survival. Timing of exposure also affected the variance components for hatching time and larval length, but in a less consistent direction than the variance components for mortality. No significant genetic variation was found for any reaction norms across time points of exposure, indicating a uniformity among genotypes in how susceptibility changed over development. Phenotypes were also typically correlated across time points, which could constrain the evolution of the reaction norms. Our experiment demonstrates that the relative maternal and paternal contributions to susceptibility to an infection, and hence the evolutionary potential to respond to pathogen-induced selection, depends not only on the kind of pathogenic stress but also on the timing of the challenge.

Plataforma de recollida de signatures digitals per a iniciatives legislatives populars

En aquest TFC s'ha dissenyat i implementat una plataforma de recollida de signatures digitals per a iniciatives legislatives populars (ILPs). Aquesta plataforma dóna la possibilitat a les comissions promotores de crear i gestionar les seves pròpies ILPs i permet als ciutadans signar digitalment aquestes iniciatives de forma que les signatures tinguin validesa legal.