456 research outputs found

    Schizotypal traits and psychotic-like experiences during adolescence: An update

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    BACKGROUND: The psychosis phenotype is distributed along a severity continuum that ranges from psychological well-being to full-blown psychosis. Schizotypal traits and psychotic-like experiences are considered as one of the possible phenotypic indicators of the latent liability for psychosis (named schizotypy). This selective review offers a general overview and update of trait schizotypy and psychotic like experiences during adolescence. METHOD: The previous literature on schizotypal traits  and psychotic like experiences is selectively reviewed. RESULTS: We begin with a brief introduction of psychosis syndrome from an extended psychosis phenotype framework as well as a brief definition of trait schizotypy and psychotic-like experiences. We introduce the study of these traits and experiences from a developmental perspective, where the psychosis proneness-persistence-impairment model is highlighted. We provide a selective review of the tools available for assessment these constructs from the psychometric high-risk paradigm. We then discuss the factorial validity of the studies conducted in adolescents. In addition, the links between this set of subclinical traits and experiences and other variables gathered from a translational approach are discussed, with the aim to establish a nomological network. CONCLUSIONS: We conclude by considering remaining questions and future directions for the understanding of trait schizotypy and psychotic-like experiences during adolescence

    New approaches on the study of the psychometric properties of the STAI

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    The main purpose of this study was to analyze the psychometric properties of the State-Trait Anxiety Inventory (STAI1). Previous studies have indicated different factor solutions. Nevertheless, there is still a lack of consensus about the best dimensional model of STAI scores.The sample consisted of 417 participants, composed of 387 (29.71% male) healthy participants (comparison group: M=35.5 years; SD=8.40), and 30 (36.66% male) patient (clinical group M=35.8 years; SD=12.94).The internal consistency evaluated through Ordinal Alpha was good, 0.98 and 0.94 in the non-clinical and the clinical samples, respectively. Test-retest reliability (two weeks) for Total Score was 0.81 for the non-clinical subsample, and 0.93 for the clinical subsample. Confirmatory factor analyses supported both a four factor model and bifactor model. Also, STAI scores showed statistically significant correlations with Burns Anxiety Inventory (Burns-A) scores. Furthermore, results showed statistically significant differences in the mean scores of the STAI between the clinical and the non-clinical subsamples.The psychometric properties of the STAI were adequate. The present study contributes to better understand the STAI structure through the comparison of new approaches in the study of the STAI internal structure. The results found may contribute in the efforts to improve the evaluation and identification of anxiety symptoms and disorders

    Low temperature thermodynamic properties near the field-induced quantum critical point in DTN

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    We present a comprehensive experimental and theoretical investigation of the thermodynamic properties: specific heat, magnetization and thermal expansion in the vicinity of the field-induced quantum critical point (QCP) around the lower critical field Hc12H_{c1} \approx 2\,T in DTN . A T3/2T^{3/2} behavior in the specific heat and magnetization is observed at very low temperatures at H=Hc1H=H_{c1} that is consistent with the universality class of Bose-Einstein condensation of magnons. The temperature dependence of the thermal expansion coefficient at Hc1H_{c1} shows minor deviations from the expected T1/2T^{1/2} behavior. Our experimental study is complemented by analytical calculations and Quantum Monte Carlo simulations, which reproduce nicely the measured quantities. We analyze the thermal and the magnetic Gr\"{u}neisen parameters that are ideal quantities to identify QCPs. Both parameters diverge at Hc1H_{c1} with the expected T1T^{-1} power law. By using the Ehrenfest relations at the second order phase transition, we are able to estimate the pressure dependencies of the characteristic temperature and field scales.Comment: 11 paged, 10 figures, submitted to PR

    Dimensiones factoriales del cuestionario de Millon (MCMI-II) en adictos a sustancias.

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    El Inventario Clinico Multiaxial de Millon (MCMI-II) es un cuestionario ampliamente utilizado en la clínica, especialmente en drogodependencias, para la evaluación de la personalidad. El objetivo del presente estudio es conocer la estructura factorial subyacente del MCMI-II en una muestra de 1.106 adictos a sustancias psicoactivas que inician tratamiento. Los participantes cumplimentaron el MCMI-II y el TCI-R. Se realizó análisis factorial exploratorio multivariado. Los resultados muestran que en el MCMI-II hay un factor principal que evalúa sintomatología de aparición reciente relacionada con el Eje I, una escala de ideación autolítica, dos escalas que exploran problemas relacionados con alcohol y otras drogas, dos de rasgos de personalidad normal y siete de rasgos de personalidad disfuncional. Aunque el objetivo del MCMI-II es evaluar la personalidad, los resultados indican que la mayor parte del mismo evalúa condiciones no necesariamente estables que han aparecido recientemente. Las escalas que miden rasgos disfuncionales de personalidad se combinan entre sí para configurar los trastornos, sin ajuste claro a la teoría de referencia. Se concluye que el uso del MCMI-II con fines diagnósticos debe considerar la presencia de condiciones inestables que pueden incrementar artefactualmente las cifras de prevalencia y de coexistencia de trastornos de personalidad y comportamientos adictivos. Factorial dimensions of the Millon’s MCMI-II in substance addicts. The Millon Clinical Multiaxial Inventory II is a widely used questionnaire for the assessment of personality in clinical settings, especially in addictive behaviors. The aim of this study is to determine the underlying factorial structure of the MCMI-II in a sample of 1,106 drug-dependents who seek treatment. All participants completed the MCMI-II and the TCI-R. Multivariate exploratory factor analysis was performed. The results show that, in the MCMI-II, there is a main part that assesses symptoms of recent onset associated with the Axis I disorders, a scale that explores autolytic ideation, two scales that explore issues related to the use of alcohol and other drugs, two scales that assess normal personality traits, and seven scales that explore dysfunctional personality traits. Although the objective of the MCMI-II is the assessment of personality, the results indicate that the largest part of the questionnaire assesses not necessarily stable conditions and which have appeared recently. The scales measuring dysfunctional personality traits are combined to account for disorders without a clear match to the theory of reference. We conclude that, when using the MCMI-II with diagnostic purposes, one should consider the presence of unstable conditions that could artifactually increase the prevalence rates and the coexistence of personality disorders and addictive behaviors

    Schizotypy: The Way Ahead

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    Background: Empirical evidence suggests that schizotypy is a useful construct for analyzing and understanding psychotic disorders. However, several issues remain to be resolved. Method: This selective, critical review, addresses some questions and limitations, and discusses future directions of work. Results: First, we present a conceptual outline and discuss the evidence from translational and interdisciplinary studies on schizotypy. Next, we examine and discuss newer analytical and methodological approaches, including network and machine learning approaches. We also discuss newer psychometric identification approaches, such as those using biobehavioral and ambulatory assessment. Next, we review recent cross-cultural studies in schizotypy research. Finally, we identify new challenges and directions and draw conclusions. Conclusions: This selective, critical review suggests that new methods can contribute to the construction of a solid scientific model of schizotypy as a risk construct. // Esquizotipia: el Camino a Seguir. Antecedentes: la evidencia empírica ha demostrado que la esquizotipia es un constructo útil para analizar y comprender los trastornos psicóticos. Sin embargo, todavía quedan por resolver varias cuestiones. Método: en esta revisión selectiva y crítica se abordan algunas limitaciones, se discuten interrogantes y se comentan direcciones futuras de trabajo. Resultados: en primer lugar, se presenta una delimitación conceptual y se comenta la evidencia acumulada en diferentes estudios y niveles de análisis en el campo de la esquizotipia. A continuación, se examinan nuevos modelos psicopatológicos, como el modelo de red, y se presentan las diferentes herramientas desarrolladas y validadas para su evaluación. Seguidamente, se abordan algunas inquietudes metodológicas de fondo y se presentan nuevas técnicas y procedimientos psicométricos, como la evaluación ambulatoria y bioconductual. También se analizan algunos de los problemas inherentes en la investigación entre países y culturas. Finalmente, se establecen las conclusiones y se abordan nuevos desafíos y direcciones futuras de investigación. Conclusiones: esta revisión selectiva y crítica plantea que es necesario continuar trabajando en la construcción de un modelo científico sólido y refutable e incorporar nuevas pruebas científicas en el campo de la esquizotipia

    Assessment of urban-scale potential for solar PV generation and consumption

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    The rise of grid electricity price and a growing awareness of climate change is resulting in an increasing number of photovoltaic facilities installed in buildings. Electricity market regulation and climatic conditions, in particular solar radiation, are the main factors that determine the economic viability of a photovoltaic facility. This paper describes a method for evaluating the potential for photovoltaic (PV) production and self-consumption for the building stock of a particular city. A GIS 3D city map is used to calculate solar irradiation. Building-level electricity use is calculated based on building type, geometry and other characteristic inferred from building age, taking the cadastre GIS as main input. The methodology identifies the realistic potential for rooftop photovoltaic installations, as well as the optimum size to be installed from an economic perspective. To represent different regulations that can affect economic viability of PV installations, calculations should adapt for the specific installation conditions and regulatory situation, as for example self-consumption and net metering. The proposed methodology is applied to a case study in Irun (Spain), where results for potential of PV generation and self-consumption for the building stock are presented. The results offer public administration a realistic view of economically viable PV potential for the city and allow to analyse different mechanisms to promote their installations. It also serves for individual electricity consumers to evaluate and optimize new photovoltaic energy facilities. Finally, it serves policy makers to estimate the repercussion of electricity market regulations on the economic viability of PV systems.The work described in this article is partially funded by the PLANHEAT project, Grant Agreement Number 723757, 2016-2019, as part of the call H2020-EE-2016-RIA-IA. This study was also supported by “Irungo Udala - Ayuntamiento de Irun” who collaborated in the data acquisition and funding

    Youth screening depression: Validation of the Patient Health Questionnaire-9 (PHQ-9) in a representative sample of adolescents

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    BACKGROUND: Depression symptoms and mood disorders constitute one of the major public health challenges among youths. Thus, early prevention and intervention for depression should be a priority. The main goal of the present study was to validate the Patient Health Questionnaire-9 (PHQ-9) scores in a school-based sample of non-clinical adolescents. METHOD: Stratified random sampling was conducted. Participants were 2235 students (M = 14.49, SD =1.76, range= 12–18 years), 52.9 % were female, from 34 secondary schools in Spain. Several previously validated self-reported questionnaires of mental health and psychopathology were administrated. RESULTS: The unidimensional factorial model of the PHQ-9 items showed adequate goodness of fit indices. Strong measurement invariance across gender was found. Omega for the PHQ-9 total score was 0.87. The PHQ-9 total score was positively associated with anxiety symptoms and emotional and behavioral problems, and negatively associated with prosocial behavior and quality of life. CONCLUSIONS: The PHQ-9 is a brief, easy, and reliable tool for assessing self-reported depressive symptoms in both clinical and school settings. PHQ-9 may be used as a screening tool for universal early detection and monitorization of depression symptoms during adolescence

    Absorción acústica de espumas de aluminio

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    The article discusses normal incidence sound absorption by aluminium foam manufactured with powder metallurgy technology. Aluminium foams with different surface morphologies were obtained by varying the type of precursor and adding filler materials during the foaming process. The sound absorption coefficients found for these aluminium foams were compared to the coefficient for commercial foams marketed under the name ALPORAS. The effect of foam thickness on the absorption coefficient was studied for each sample prepared. The combination of good acoustic and mechanical properties makes aluminium foams particularly attractive products. The study included an analysis of the effect of 2-, 5- and 10-cm air gaps on the sound absorption coefficient. The results showed that such gaps, which are routinely used in construction to reduce the reverberation period in indoor premises, raised the low frequency absorption coefficient significantly. This increase was found to depend on aluminium foam density and thickness and the depth of the air gap. In this same line, we have investigated the absorption coefficient of the aluminium foams combined with a mineral fiber panel.Se presenta un estudio del coeficiente de absorción acústica a incidencia normal de espumas de aluminio fabricadas mediante la técnica pulvimetalúrgica. Se fabricaron espumas de aluminio de distinta morfología superficial variando el tipo de precursor y usando materiales de relleno durante el proceso de espumación. Se muestra un estudio comparativo del coeficiente de absorción acústica de las espumas de aluminio fabricadas y las espumas comerciales conocidas como ALPORAS. Para cada muestra fabricada se estudió la influencia del espesor sobre el valor del coeficiente de absorción.El atractivo de las espumas de aluminio radica en que en ellas se combinan interesantes propiedades acústicas y mecánicas. Se analizó el efecto de una cámara de aire de 2, 5 y 10 cm de anchura sobre el coeficiente de absorción acústica, solución constructiva habitual para reducir el tiempo de reverberación en un recinto. Los resultados muestran que se consigue un aumento significativo del valor del coeficiente de absorción a bajas frecuencias. Este aumento depende de la densidad y espesor de la espuma de aluminio y de la anchura de la cámara de aire. En esta misma línea, y dado el uso habitual de lanas minerales como absorbentes acústicos también se investigó el coeficiente de absorción a incidencia normal de la espuma de aluminio con una lana mineral

    UV-C irradiation is able to inactivate pathogens found in commercially collected porcine plasma as demonstrated by swine bioassay

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    Liquid porcine plasma is an animal origin raw material for the manufacturing process of spray-dried porcine plasma that is used in pig nutrition worldwide. In previous studies we found that the application of ultraviolet light C (UV-C) in liquid plasma that was inoculated with a variety of bacteria or viruses of importance in the swine industry can be considered as redundant safety steps because in general achieve around 4 logs reduction for most of these pathogens. However, the final validation of the UV-C light as safety feature should be conducted with commercial liquid plasma and using the pig bioassay model. As a first objective, the potential infectivity of a raw liquid plasma product collected from an abattoir was tested by means of a swine bioassay. We used Porcine circovirus 2 (PCV-2), a ubiquitous virus that has been systematically detected by PCR in porcine plasma at abattoirs as selection criteria for commercial liquid plasma lot. As a second aim of the study, the effects of different doses of UV-C irradiation on the selected raw liquid plasma were assayed in the animal bioassay. Moreover, other swine infecting agents, including Porcine reproductive and respiratory syndrome virus (PRRSV), were also determined in the original plasma and monitored in the inoculated animals. Pigs negative for PCV-2 and PRRSV genome and antibodies were allotted to one of five groups (6 to 8 pigs/ group) and injected intra-peritoneally with 10 mL of their assigned inoculum at 50 d of age. Negative control pigs (group 1) were injected with PBS. Positive control pigs (group 5) were injected with a PCV-2 inoculum. Groups 2, 3 and 4 were injected with liquid porcine plasma that had been subjected to 0 (raw plasma), 3000 or 9000 J/L UV-C irradiation, respectively. Group 2 pigs (0 J/L UV-C) got infection by PRRSV but no PCV-2 infection or seroconversion. However, one pig from group 2 seroconverted to Rotavirus A (RVA) and Hepatitis E virus (HEV) and three group 2 pigs seroconverted to Porcine parvovirus (PPV). Groups 1, 3 and 4 pigs showed no evidence of infection or seroconversion associated with the tested viruses or any other pathogens found in the liquid plasma before UV-C irradiation. Group 5 pigs developed PCV-2 infectivity as expected. UV-C irradiation of liquid plasma at 3000 and 9000 J/L was effective in preventing PRRSV and other pathogens transmission. Moreover, raw liquid plasma was non-infectious for PCV-2 in naïve pigs.info:eu-repo/semantics/publishedVersio
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