730 research outputs found

    Una ecuación de estado en los gases

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    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

    Electrochemical Reduction of CO2: Influence of Pre-treating the Carbon Support

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    The production of useful chemicals by electroreducing CO2 it is a promising approach to reduce the levels of this greenhouse gas in the atmosphere. This is not a straightforward process due to the high stability of the CO2 molecule and low selectivity however, these barriers can be overcome by using an appropriate catalyst. This research focus on the effect of pre-treating the carbon supports before incorporating the catalyst on the electroreduction of CO2. We found that the electrochemical behaviour of the carbon supports is modified by the nature of the pre-treatment used. From the structure perspective, the results showed partial destruction of the carbon structure mainly after the oxidative treatments nevertheless, the introduction of defect sites in the carbon structure contributed to catalyst performance. This improvement was proved by the LSV data that showed the reduction of the current associated with the hydrogen reduction reaction

    H - T phase diagram of YbCo2Si2 with H // [100]

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    We report on the first high-resolution dc-magnetisation (MM) measurements on a single crystal of \ycs. MM was measured down to 0.05 K and in fields up to 12 T, with the magnetic field HH parallel to the crystallographic direction [100]. Two antiferromagnetic (AFM) phase transitions have been detected in a field μ0H=0.1\mu_{0}H = 0.1 T at TN=1.75T_{N} = 1.75 K and TL=0.9T_{L} = 0.9 K, in form of a sharp cusp and a sudden drop in χ=M/H\chi = M/H, respectively. These signatures suggest that the phase transitions are 2nd2^{nd} order at TNT_{N} and 1st1^{st} order at TLT_{L}. The upper transition is suppressed by a critical field μ0HN=1.9\mu_{0}H_{N} = 1.9 T. The field-dependent magnetisation shows two hysteretic metamagnetic-like steps at the lowest temperature, followed by a sharp kink, which separates the AFM region from the paramagnetic one. The magnetic HTH - T phase diagram of \ycs has been deduced from the isothermal and isofield curves. Four AFM regions were identified which are separated by 1st1^{st} and 2nd2^{nd} order phase-transition lines.Comment: 5 Pages, 3 figure

    Magnetic phase diagram of YbCo2Si2 derived from magnetization measurements

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    We report on high-resolution dc-magnetization (M) measurements on a high-quality single crystal of YbCo2Si2. M was measured down to 0.05K and in fields up to 4T, with the magnetic field oriented along the crystallographic directions [100], [110] and [001] of the tetragonal structure

    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

    Stabilization of p21 by mTORC1/4E-BP1 predicts clinical outcome of head and neck cancers

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    The levels, regulation and prognostic value of p21 in head and neck squamous cell carcinomas (HNSCC) has been puzzling for years. Here, we report a new mechanism of regulation of p21 by the mTORC1/4E-BP1 pathway. We find that non-phosphorylated 4E-BP1 interacts with p21 and induces its degradation. Accordingly, hyper-activation of mTORC1 results in phosphorylation of 4E-BP1 and stabilization of p21. In HNSCC, p21 levels strongly correlate with mTORC1 activity but not with p53 status. Finally, clinical data indicate that HNSCC patients with p21 and phospho-S6-double-positive tumours present a better disease-specific survival. We conclude that over-activation of the mTORC1/4E-BP1/p21 pathway is a frequent and clinically relevant alteration in HNSCC.We are grateful to Reidar Grenman, Silvio Gutkind, Nahum Sonenberg, Gordon Peters, David Sabatini and Mariano Barbacid for sharing critical reagents. We also thank Aurora Astudillo, Aitana Vallina, Laura Alonso-Dura ́n and Eva Allonca for excellent technical assistance. Work in the laboratory of M.S. is funded by the CNIO and by grants from the Spanish Ministry of Economy (SAF) co-funded by the European Regional Development Fund, the European Research Council (ERC Advanced Grant), the Regional Government of Madrid co-funded by the European Social Fund, the Botin Foundation and BancoSantander (Santander Universities Global Division), the Ramon Areces Foundation an the AXA Foundation. Work in the laboratory of J.M.G.-P. and J.P.R. was supported bygrants from Plan Nacional de DþI 2013–2016 ISCIII (CP13/00013 andPI13/00259),RD12/0036/0015 of Red Tematica de Investigacio ́n Cooperativa en Cancer (RTICC), Spain and the FEDER Funding Program from the European UnionS

    Mobility assessment in people with Alzheimer disease using smartphone sensors

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    [EN] Background Understanding the functional status of people with Alzheimer Disease (AD), both in a single (ST) and cognitive dual task (DT) activities is essential for identifying signs of early-stage neurodegeneration. This study aims to compare the performance quality of several tasks using sensors embedded in an Android device, among people at different stages of Alzheimer and people without dementia. The secondary aim is to analyze the effect of cognitive task performance on mobility tasks. Methods This is a cross-sectional study including 22 participants in the control group (CG), 18 in the group with mild AD and 22 in the group with moderate AD. They performed two mobility tests, under ST and DT conditions, which were registered using an Android device. Postural control was measured by medial-lateral and anterior-posterior displacements of the COM (MLDisp and APDisp, respectively) and gait, with the vertical and medial-lateral range of the COM (Vrange and MLrange). Further, the sit-to-stand (PStand) and turning and sit power (PTurnSit), the total time required to complete the test and the reaction time were measured. Results There were no differences between the two AD stages either for ST or DT in any of the variables (p > 0.05). Nevertheless, people at both stages showed significantly lower values of PStand and PTurnSit and larger Total time and Reaction time compared to CG (p < 0.05). Further, Vrange is also lower in CDR1G than in CG (p < 0.05). The DT had a significant deleterious effect on MLDisp in all groups (p < 0.05) and on APDisp only in moderate AD for DT. Conclusions Our findings indicate that AD patients present impairments in some key functional abilities, such as gait, turning and sitting, sit to stand, and reaction time, both in mild and moderate AD. Nevertheless, an exclusively cognitive task only influences the postural control in people with AD.This work was funded by the Spanish Government, Secretaria de Estado de Investigacion, Desarrollo e Innovacion, and co-financed by EU FEDER funds (Grant DPI2013-44227-R). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Serra-Añó, P.; Pedrero, J.; Hurtado-Abellán, J.; Inglés, M.; Espí-López, G.; Lopez Pascual, J. (2019). Mobility assessment in people with Alzheimer disease using smartphone sensors. Journal of NeuroEngineering and Rehabilitation. 16(1). https://doi.org/10.1186/s12984-019-0576-yS161Association A. 2017 Alzheimer’s disease facts and figures. Alzheimers Dement. 2017;13(4):325–73.Harrington MG, Chiang J, Pogoda JM, Gomez M, Thomas K, Marion SD, et al. Executive function changes before memory in preclinical Alzheimer’s pathology: a prospective, cross-sectional, case control study. 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    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

    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
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