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1.
Entropy (Basel) ; 26(1)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38275497

RESUMEN

Superconducting circuits reveal themselves as promising physical devices with multiple uses. Within those uses, the fundamental concept of the geometric phase accumulated by the state of a system shows up recurrently, as, for example, in the construction of geometric gates. Given this framework, we study the geometric phases acquired by a paradigmatic setup: a transmon coupled to a superconductor resonating cavity. We do so both for the case in which the evolution is unitary and when it is subjected to dissipative effects. These models offer a comprehensive quantum description of an anharmonic system interacting with a single mode of the electromagnetic field within a perfect or dissipative cavity, respectively. In the dissipative model, the non-unitary effects arise from dephasing, relaxation, and decay of the transmon coupled to its environment. Our approach enables a comparison of the geometric phases obtained in these models, leading to a thorough understanding of the corrections introduced by the presence of the environment.

2.
Entropy (Basel) ; 25(9)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37761548

RESUMEN

Shortcuts to adiabaticity (STA) are relevant in the context of quantum systems, particularly regarding their control when they are subjected to time-dependent external conditions. In this paper, we investigate the completion of a nonadiabatic evolution into a shortcut to adiabaticity for a quantum field confined within a one-dimensional cavity containing two movable mirrors. Expanding upon our prior research, we characterize the field's state using two Moore functions that enables us to apply reverse engineering techniques in constructing the STA. Regardless of the initial evolution, we achieve a smooth extension of the Moore functions that implements the STA. This extension facilitates the computation of the mirrors' trajectories based on the aforementioned functions. Additionally, we draw attention to the existence of a comparable problem within nonrelativistic quantum mechanics.

3.
Entropy (Basel) ; 25(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36673159

RESUMEN

The development of quantum technologies present important challenges such as the need for fast and precise protocols for implementing quantum operations. Shortcuts to adiabaticity (STAs) are a powerful tool for achieving these goals, as they enable us to perform an exactly adiabatic evolution in finite time. In this paper, we present a shortcut to adiabaticity for the control of an optomechanical cavity with two moving mirrors. Given reference trajectories for the mirrors, we find analytical expressions that give us effective trajectories which implement an STA for the quantum field inside the cavity. We then solve these equations numerically for different reference protocols, such as expansions, contractions and rigid motions, thus confirming the successful implementation of the STA and finding some general features of these effective trajectories.

4.
Child Psychiatry Hum Dev ; 48(4): 619-631, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27714483

RESUMEN

Developmental heterogeneity of youth conduct problems has been widely assumed, leading to the identification of distinctive groups at particular risk of more serious problems later in development. The present study intends to expand the main results of a prior study focused on identifying developmental trajectories of conduct problems (Stable-low, Stable-high, and Decreasing), by analyzing their developmental course and related outcomes during middle/late adolescence and early adulthood. Two follow-up studies were conducted 10 and 12 years after the initial study with 115 and 122 youths respectively (mean = 17.29 and 19.18). Overall results underline that the Early-onset persistent group showed the highest risk-profile; the Childhood-limited group revealed a moderate level of later maladjustment; and the Adolescence-onset group, currently identified, showed a significant peak of risk particularly in middle/late adolescence. These findings provide a more comprehensive representation of youth conduct problems, and open new means of discussion in terms of preventive intervention.


Asunto(s)
Trastorno de la Conducta/fisiopatología , Desarrollo Humano/fisiología , Adolescente , Desarrollo del Adolescente/fisiología , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , Riesgo , Adulto Joven
5.
Adicciones ; 29(3): 150-162, 2017 Jun 28.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27749966

RESUMEN

The aim of this study is to evaluate the long-term effects of a manualised program which intervenes on children with early-onset conduct problems, their families and teachers. The program evaluation involved 14 primary schools which were randomly assigned to the intervention (45 participating families) and control (30 families) conditions during 2007-2008. After a screening process which identified children with significant conduct problems both at home with their family and at school, the program was implemented in eight schools. Seven years later, 58 families (37 from the intervention group and 21 from the control group), with characteristics equivalent to those of the study's entire initial group, were contacted again. With measures administered to the children and their parents, comparisons through multivariate analyses of variance between intervention and control groups supported the program's efficacy in reducing both conduct problems and relations with antisocial peers. Furthermore, the program fostered social and communication skills. As regards drug use, the intervention group showed less favourable attitudes towards drugs, lower intention of drug use, lower frequency of tobacco use and lower intensity of alcohol use. These results support the usefulness of multicomponent programs for conduct problems as a way to prevent, in the long term, unfavourable developmental trajectories, where drug use is a key element.


Este trabajo tiene como objetivo evaluar los efectos a largo plazo de un programa manualizado que interviene sobre niños con problemas de conducta, sus familias y sus profesores. El programa involucró, durante el curso 2007-08, a 14 escuelas que fueron asignadas aleatoriamente a las condiciones de intervención (45 familias participantes) y control (30 familias). A partir de un screening que identificó niños con problemas significativos de conducta en la familia y en la escuela, el programa fue aplicado en ocho de esos centros. Siete años más tarde, se pudo contactar de nuevo con 58 familias (37 de intervención y 21 control), con características equivalentes al total de participantes en el estudio inicial. Por medio de informes obtenidos de los participantes y de sus padres, y a través de comparaciones con análisis multivariables de la varianza, se apoya la eficacia del programa en la reducción de los problemas de conducta y de la implicación con amigos antisociales. Asimismo, se encuentra que el programa promueve la competencia social y comunicativa de los participantes. En cuanto al consumo de drogas, el grupo de intervención muestra actitudes menos favorables hacia las drogas, menor intención de consumo, menor frecuencia de consumo de tabaco y menor intensidad de consumo de alcohol. Estos resultados apoyan la utilidad de los programas multicomponente de intervención sobre los problemas de conducta como una vía para prevenir, a largo plazo, trayectorias de desarrollo desfavorables, en las que el consumo de drogas es una pieza fundamental.


Asunto(s)
Problema de Conducta , Trastornos Relacionados con Sustancias/prevención & control , Niño , Intervención Educativa Precoz , Femenino , Estudios de Seguimiento , Humanos , Masculino , Evaluación de Programas y Proyectos de Salud , Factores de Tiempo
6.
Res Child Adolesc Psychopathol ; 50(4): 505-519, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34499292

RESUMEN

Research into co-occurrent internalizing and externalizing problems during childhood is flourishing. In particular, investigation on the association between anxiety and externalizing problems has yielded mixed findings, focused mainly on the issue of which problem might precede the other, and what role anxiety plays with respect to externalizing problems. Relatively little attention has been paid to the developmental patterns of these behaviors from early childhood, despite the potential of such knowledge to fully delineate etiological models of co-occurrence. This study aimed to examine the longitudinal association of anxiety and externalizing problems in a community sample of preschoolers (ELISA Project; N = 2,341; 48.2% girls), by identifying empirically derived profiles and then describing their change and stability through the use of Latent Transition Analysis. Gender differences were explored. Four different profiles were identified: "typically developing", "mainly anxious", "modestly externalizing" and "co-occurrent". Membership in these profile groups showed high stability over a two-year period. However, children in the "co-occurrent" profile group were the most likely to show changes, predominantly towards "modestly externalizing". Furthermore, a significant gender difference for transitions towards the "co-occurrent" profile group was found, with girls showing less likelihood of being assigned to such profile. These findings show that it is possible to identify an early persistent course of co-occurrent anxiety and externalizing problems, as well as observe changes in co-occurrence towards a simpler externalizing behavioral expression. Further research should explore predictors of group membership and changes in membership, that are malleable and therefore open to preventative intervention.


Asunto(s)
Trastornos de Ansiedad , Ansiedad , Ansiedad/epidemiología , Niño , Preescolar , Femenino , Humanos , Masculino , Factores Sexuales
7.
Psicothema ; 22(3): 410-5, 2010 Aug.
Artículo en Español | MEDLINE | ID: mdl-20667268

RESUMEN

The main purposes of this study are: a) To determine whether the acculturation styles proposed by Berry's model (integration, separation, assimilation and marginalization) can be replicated in a sample of Latin-American immigrant adolescents living in Spain; b) to examine the relationships between acculturation styles and both antisocial behavior and involvement with alcohol. For these purposes, data were collected in a sample of 750 Latin-American immigrants in a number of schools in Galicia and Madrid. Results confirm the existence of the four acculturation strategies, with integration and marginalization as the most and least used, respectively. With respect to the relationships of these styles with antisocial behavior and alcohol use, it was found that adolescents who use the separation strategy show the highest levels of antisocial behavior; conversely, and contrary to expectations, the marginalization group had the lowest levels of antisocial involvement.


Asunto(s)
Aculturación , Trastorno de Personalidad Antisocial/epidemiología , Adolescente , Niño , Femenino , Humanos , América Latina , Masculino
8.
Artículo en Inglés | MEDLINE | ID: mdl-32987641

RESUMEN

The present study aimed to examine the effects of the Spanish confinement derived from the COVID-19 crisis on children and their families, accounting for child's age. A range of child negative (e.g., conduct problems) and positive outcomes (e.g., routine maintenance) were examined, along with a set of parent-related variables, including resilience, perceived distress, emotional problems, parenting distress and specific parenting practices (e.g., structured or avoidant parenting), which were modeled through path analysis to better understand child adjustment. Data were collected in April 2020, with information for the present study provided by 940 (89.6%) mothers, 102 (9.7%) fathers and 7 (0.7%) different caregivers, who informed on 1049 Spanish children (50.4% girls) aged 3 to 12 years (Mage = 7.29; SD = 2.39). The results suggested that, according to parents' information, most children did not show important changes in behavior, although some increasing rates were observed for both negative and positive outcomes. Child adjustment was influenced by a chain of effects, derived from parents' perceived distress and emotional response to the COVID-19 crisis, via parenting distress and specific parenting practices. While parenting distress in particular triggered child negative outcomes, specific parenting practices were more closely related to child positive outcomes. These findings may help to better inform, for potential future outbreaks, effective guidelines and prevention programs aimed at promoting the child's well-being in the family.


Asunto(s)
Conducta Infantil , Infecciones por Coronavirus/psicología , Responsabilidad Parental , Padres/psicología , Neumonía Viral/psicología , Cuarentena/psicología , Betacoronavirus , COVID-19 , Niño , Preescolar , Femenino , Humanos , Masculino , Pandemias , Distrés Psicológico , SARS-CoV-2 , España
9.
J Ethn Subst Abuse ; 8(4): 400-12, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20057918

RESUMEN

This study examines how cohesion and parent­child conflict relate to alcohol use among Mexican-heritage adolescents. The sample consists of 120 adolescents (14 to 18 years) participants from the Southwest sub-sample of the Latino Acculturation and Health Project. Lifetime and recent alcohol use and binge drinking were tested. Results from the logistic regressions identified high and low levels of family cohesion as a risk factor for alcohol use compared to medium levels of cohesion, and parent­child conflict predicted lifetime use and binge drinking. Low and high family cohesion levels appear to be especially problematic among Mexican adolescents who are trying to navigate two different cultural worlds. Although high family cohesion is often a characteristic of Mexican families, Mexican-heritage adolescents may view high family cohesion as a hindrance to their own independence. Unresolved conflict seems to be connected to children's problem behaviors and alcohol misuse could be utilized by adolescents as a mechanism to reduce emotional distress caused by family tensions.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Conflicto Familiar , Americanos Mexicanos/estadística & datos numéricos , Relaciones Padres-Hijo , Adolescente , Conducta del Adolescente/etnología , Consumo de Bebidas Alcohólicas/etnología , Recolección de Datos , Femenino , Humanos , Modelos Logísticos , Masculino
10.
Int J Offender Ther Comp Criminol ; 63(10): 1896-1913, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30973032

RESUMEN

One of the main purposes of juvenile risk assessment is to distinguish different risk profiles, which may lead to referring youths into specific intervention programs tailored to their specific needs. This study is devoted to identifying main typologies of risk in a sample of 286 Spanish young offenders aged 14 to 22 (M = 17.36; SD = 1.61) years. Participants were classified into different profiles, representing different levels of risk in terms of individual and psychosocial dynamic variables. A three-class (low-, middle-, and high-risk profiles) and a four-class (low-, middle-, high-risk family problems/callous-unemotional (CU) traits, and high-risk impulsive/undercontrolled) solutions were identified. These profiles showed their distinctiveness and meaningfulness in a set of comparisons on antisocial behavior and prior offenses measures. These findings highlight the presence of diverse patterns of risk and suggest that a limited number of specialized interventions may respond to the main needs of most institutionalized youths.


Asunto(s)
Trastorno de Personalidad Antisocial/clasificación , Delincuencia Juvenil , Medición de Riesgo , Adaptación Psicológica , Adolescente , Ira , Conflicto Familiar , Femenino , Hostilidad , Humanos , Conducta Impulsiva , Masculino , Responsabilidad Parental , Grupo Paritario , Resiliencia Psicológica , Asunción de Riesgos , Apoyo Social , España , Ideación Suicida , Violencia , Adulto Joven
11.
Subst Use Misuse ; 43(11): 1571-93, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18752161

RESUMEN

This study aims to comparatively examine drug use in Arizona and Spain, in order to know if similarities and differences in drug use patterns justify the administration in Spain of U.S. prevention intervention programs. Data were obtained from independent samples of seventh-grade students recruited from urban public schools and surveyed in 1998: 4,035 ethnically diverse Arizona students (Latinos and non-Hispanic Whites), and 2,243 Spanish-White students. Comparisons using Odds ratios and Chi-square tests allowed assessment of differences in drug use rates between preadolescents in Arizona and Spain taking into account gender. Furthermore, ethnicity differences in preadolescent drug use and in psychosocial risk factors were explored using multivariate analysis (ANOVA and logistic regression). Our results showed similar trends in drug use between Arizona and Spain students, with gateway drugs already in use by early adolescents, and with higher rates of drug use among males than among females. However, cross-national differences in marijuana/cannabis use were noteworthy: Arizona preadolescents were over 25 times more likely to report marijuana/cannabis use than preadolescents from Spain. Moreover, when ethnic differences were considered, Latinos in Arizona reported higher marijuana/cannabis use compared with non-Latino students. Drug use patterns among Latino preadolescents, as well as the relevance of some risk factors among the diverse groups, were strongly influenced by their level of acculturation. Study limitations and the implications of our findings for early drug use prevention and future research are discussed.


Asunto(s)
Conducta Infantil , Trastornos Relacionados con Sustancias/etnología , Trastornos Relacionados con Sustancias/epidemiología , Aculturación , Adolescente , Arizona/epidemiología , Niño , Recolección de Datos , Femenino , Humanos , Masculino , Psicología , España/epidemiología , Trastornos Relacionados con Sustancias/prevención & control
12.
Psicothema ; 19(2): 269-75, 2007 May.
Artículo en Español | MEDLINE | ID: mdl-17425898

RESUMEN

The Antisocial Personality Questionnaire developed by Blackburn and Fawcett (1999) has shown adequate reliability and validity in studies of male offenders interned in psychiatric hospitals. This paper provides data on the APQ collected from a sample of offenders (males and females) without any diagnosed mental illness. The sample was made up of 216 offenders (108 males and 108 females) confined in Spanish prisons. We analyzed the psychometric properties of the instrument and we also examined differences in personality as a function of gender and type of crime (violent vs. non-violent). Results support the reliability of the APQ scales as well as the structure proposed by Blackburn. Additionally, we selected items that discriminate between offenders convicted for violent and non-violent crimes; when these items are factorized, a three-factor structure emerges, resembling Eysenck's model.


Asunto(s)
Trastorno de Personalidad Antisocial/psicología , Crimen/psicología , Inventario de Personalidad , Prisioneros/psicología , Violencia/psicología , Adolescente , Adulto , Anciano , Trastorno de Personalidad Antisocial/diagnóstico , Trastorno de Personalidad Antisocial/epidemiología , Crimen/estadística & datos numéricos , Femenino , Humanos , MMPI , Masculino , Persona de Mediana Edad , Prisioneros/estadística & datos numéricos , Psicometría/estadística & datos numéricos , Factores Sexuales , Violencia/estadística & datos numéricos
13.
Phys Rev E ; 96(1-1): 013307, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29347069

RESUMEN

We present an alternative numerical approach to compute the number of particles created inside a cavity due to time-dependent boundary conditions. The physical model consists of a rectangular cavity, where a wall always remains still while the other wall of the cavity presents a smooth movement in one direction. The method relies on the setting of the boundary conditions (Dirichlet and Neumann) and the following resolution of the corresponding equations of modes. By a further comparison between the ground state before and after the movement of the cavity wall, we finally compute the number of particles created. To demonstrate the method, we investigate the creation of particle production in vibrating cavities, confirming previously known results in the appropriate limits. Within this approach, the dynamical Casimir effect can be investigated, making it possible to study a variety of scenarios where no analytical results are known. Of special interest is, of course, the realistic case of the electromagnetic field in a three-dimensional cavity, with transverse electric (TE)-mode and transverse magnetic (TM)-mode photon production. Furthermore, with our approach we are able to calculate numerically the particle creation in a tuneable resonant superconducting cavity by the use of the generalized Robin boundary condition. We compare the numerical results with analytical predictions as well as a different numerical approach. Its extension to three dimensions is also straightforward.

14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(6 Pt 2): 066105, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16906912

RESUMEN

We study the effects of the environment on tunneling in an open system described by a static double-well potential. We describe the evolution of a quantum state localized in one of the minima of the potential at t = 0, in both the limits of high and zero environment temperature. We show that the evolution of the system can be summarized in terms of three main physical phenomena--namely, decoherence, quantum tunneling, and noise-induced activation--and we obtain analytical estimates for the corresponding time scales. These analytical predictions are confirmed by large-scale numerical simulations, providing a detailed picture of the main stages of the evolution and of the relevant dynamical processes.

15.
Span J Psychol ; 17: E97, 2014 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-26055900

RESUMEN

Previous research has shown the relevance of psychopathic traits as predictors of severe and persistent antisocial behavior. Given that personality traits refer to developmental constructs, the main purposes of this study were to analyze the stability of psychopathic traits from childhood to adolescence, and to examine differential outcomes derived from distinctive pathways of stability and change. Data was collected in a Spanish sample of 138 children aged 6-11 at the onset of the study (T1), and 12-17 in the subsequent follow-up conducted 6 years later (T2). The stability of psychopathic traits was assessed in terms of differential continuity (rank-order), absolute stability (mean-level) and individual-level change (Reliable Change Index). Results confirmed that psychopathic traits remained moderately to highly stable from childhood to adolescence (p < .001). There were, however, some differences depending on the informant (parents vs. teachers) and the particular assessment method used (rank order vs. mean-level and RCI). A stable high and an increasing developmental pattern of psychopathic traits were related with severe adolescent behavioral and psychosocial problems (ŋ² = .10-.36). These results support the usefulness of youth psychopathic personality as a developmental construct, and highlight its relevance as a predictor of long-lasting maladjustment, with relevant implications in terms of prevention and treatment.


Asunto(s)
Trastorno de Personalidad Antisocial/psicología , Adolescente , Factores de Edad , Trastorno de Personalidad Antisocial/epidemiología , Niño , Conducta Infantil/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Psicopatología , Conducta Social
16.
Ethn Health ; 13(2): 149-70, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18425712

RESUMEN

This article reports the results of a descriptive study conducted with middle school and high school age youth residing in northwestern Spain. The main outcome of the study is to advance knowledge about the drug use attitudes and behaviors of immigrants versus native youth in a social context where Latin American immigrants share a common language and a set of core cultural norms with the host society. The research was conducted by a bi-national Spain-US research team as a preliminary study leading to the development of joint culturally appropriate prevention interventions for youth in the northern region of Galicia, Spain. Surveys were administered in Spring 2005 to 817 students in 7th to 10th grades in 10 urban, secondary schools with high immigrant enrollment. The sample included Spanish natives (two-thirds) and Latin American immigrants (one-third), mainly from Colombia, Argentina, and Venezuela. Multiple regression analyses predicted substance use intentions, and a composite variable measuring lifetime and last 30-day frequency and amount of alcohol, cigarette and marijuana use. Controlling for the fact that the immigrant students were generally older and performing less well academically than natives, and for other predictors, Latin American immigrant youth were less at risk than native youth on their intentions to use substances and on their reported actual substance use. In a mediational analysis, most of the key explanatory variables in youth substance use etiology failed to account for the immigrant versus native differences, including a range of risk and protective factors for substance use, substance use norms, strength of ethnic identity, and degree of social integration within native-born social networks. Differential access to drugs mediated the immigrant-native gap in substance use intentions but did not mediate differences in actual substance use.


Asunto(s)
Cultura , Emigrantes e Inmigrantes , Trastornos Relacionados con Sustancias/etnología , Adolescente , Conducta del Adolescente/etnología , Composición Familiar , Femenino , Conductas Relacionadas con la Salud/etnología , Humanos , América Latina/etnología , Masculino , Proyectos Piloto , Factores de Riesgo , Medio Social , España
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