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1.
Phys Rev E ; 106(5-2): 055106, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36559449

ABSTRACT

We analyze numerically the effect of a slight inclination in the lowest part of the snaking branches of convectons that are present in negative separation ratio binary mixtures in two-dimensional elongated rectangular cells. The exploration reveals the existence of novel stationary localized solutions with striking spatial features different from those of convectons. The numerical continuation of these solutions with respect to the inclination of the cell unveils the existence of even further families of localized structures that can organize in closed branches. A variety of localized solutions coexist for the same heating and inclination, depicting a highly complex scenario for solutions in the lowest part of the snaking diagrams for moderate to high heating. The different localized solutions obtained in the horizontal cell are discussed in detail.

2.
Psychol Res Behav Manag ; 15: 227-235, 2022.
Article in English | MEDLINE | ID: mdl-35140533

ABSTRACT

BACKGROUND: Family members who have children with Severe Mental Disorder under their care have a hard impact on them as they are faced with the task of attending to their demands and care. This is a change in their lives as it significantly interferes with their physical and social well-being. The aim of this study was to explore the relationships between self-stigma, depression, stress and anxiety and their relationship with healthy habits, such as sport and a healthy diet. METHODS: The sample consisted of 538 parents aged between 38 and 52 years (M = 43.42; SD = 13.11). The parents have children with a diagnosis of mental disorder under their care. Participants completed the Spanish adaptation of the Self-Stigma in Relatives of people with Mental Illness (SSRMI), the Depression, Anxiety and Stress Scale (DASS-21), the Kidmed Scale and the WHO scale, whose responses were analysed using structural equation modelling. RESULTS: The results showed that self-stigma was positively related to anxiety, stress and depression and, in turn, these three variables were negatively related to sporting activity and healthy eating. CONCLUSION: This study, therefore, is further evidence of the impact of self-stigma at the physical and mental level on family members, which highlights the need to provide them with support tools and resources, and to work on raising social awareness of mental disorders.

3.
Article in English | MEDLINE | ID: mdl-34299835

ABSTRACT

Sometimes, relatives of children with autism experience feelings of guilt, abandonment and devaluation, as they tend to see themselves as the cause of their children's illness. This causes social isolation and psychological discomfort. However, there are no scales that assess self-stigma. Therefore, the aim of the study is to show evidence of the validity and reliability of the Self-Stigma Scale in Relatives of People with Mental Illness in the Spanish context in relation to autism. A total of 287 progenitors participated in the study. For the validation and adaptation process, three confirmatory factor analyses, analysis of invariance across gender, reliability analysis and temporal stability, were carried out. The results revealed that the factor structure of the questionnaire was adequate, showing adequate levels of reliability.


Subject(s)
Autistic Disorder , Child , Humans , Psychometrics , Reproducibility of Results , Social Stigma , Surveys and Questionnaires
4.
Nutrients ; 13(2)2021 Feb 09.
Article in English | MEDLINE | ID: mdl-33572125

ABSTRACT

Childhood obesity and sedentary lifestyles are now gaining a foothold in the Western world. The aim of this research was to analyse the influence of physical education classes on a healthy diet (i.e., Mediterranean diet). To this end, psychological constructs derived from the theory of self-determination and the theory of planned behaviour were taken into account, such as the satisfaction and frustration of basic psychological needs, motivation in physical education classes, and social cognition and intention. A total of 3415 secondary school students (13-19 years) participated in this study. A structural equation model was proposed that would explain the relationships between the variables mentioned above and the adherence to a Mediterranean diet. The results provide adequate fit indexes for the proposed model. Based on the results of the study, it was concluded that a high satisfaction perceived in the physical education classes would help to reinforce the intention of having a healthy diet and therefore help to generate a perdurable commitment to this habit.


Subject(s)
Diet, Mediterranean , Health Behavior , Physical Education and Training/methods , Adolescent , Health Behavior/physiology , Healthy Lifestyle , Humans , Motivation , Pediatric Obesity/prevention & control , Personal Autonomy , Personal Satisfaction , Physical Education and Training/statistics & numerical data , School Health Services/statistics & numerical data , Sedentary Behavior , Spain , Students/psychology
5.
Article in English | MEDLINE | ID: mdl-33096777

ABSTRACT

Currently, the university failure rate is around 33% of students starting their studies. Among the main reasons are demanding academic situations and the use of inappropriate coping strategies. Therefore, the aim of this study was to analyze the influence of teacher leadership on academic resilience and motivation, burnout, and academic performance. This study involved 3354 university students. A structural equation model was made to analyze the predictive relationships between the study's variables. The results showed that teacher leadership positively predicted academic resilience and motivation; academic resilience negatively predicted burnout and positively predicted academic performance; likewise, academic motivation negatively predicted burnout and positively predicted academic performance; finally, burnout negatively predicted academic resilience.


Subject(s)
Academic Performance , Burnout, Professional , Leadership , Motivation , Burnout, Psychological , Humans , Students , Universities
6.
Nutrients ; 12(8)2020 Aug 11.
Article in English | MEDLINE | ID: mdl-32796645

ABSTRACT

During their sporting lives, athletes must face multiple difficulties that can have consequences for their mental health and changes in their eating patterns. Therefore, the present study aims to analyze how social skills of the trainer influence the coping capacity, psychological well-being, and eating habits of the athlete, elements that are key to achieving success during competition. This study involved 1547 athletes and 127 trainer. In order to achieve the objective, the mean, standard deviation, bivariate correlations, reliability analysis and a structural equation model were analysed. The results showed that prosocial behaviours were positively related to resilience, while antisocial behaviours were negatively related. Resilience was negatively related to anxiety, stress and depression. Finally, anxiety, stress and depression were negatively related to healthy eating and positively related to unhealthy eating. These results highlight the importance of creating a positive social climate to develop coping strategies that promote mental health and healthy eating habits of athletes.


Subject(s)
Athletes/psychology , Feeding Behavior/psychology , Mentors/psychology , Resilience, Psychological , Social Behavior , Adult , Anxiety/psychology , Depression/psychology , Female , Humans , Male , Mentoring , Middle Aged , Stress, Psychological/psychology
7.
Article in English | MEDLINE | ID: mdl-32481697

ABSTRACT

The interaction between the teacher and the student is essential in order to encourage adherence to physical exercise or sports by young people. In this sense, the support of the autonomy of the teacher for the students has been analyzed in a one-dimensional way. Therefore, the aim of this study was to adapt and validate the Multidimensional Scale of Support for Autonomy Perceived for Physical Education the context of Spanish to physical exercise, in order to have a multidimensional scale. A total of 2329 young people from various educational centers in Andalusia (Spain) participated in the study. The factorial structure of the questionnaire was examined through an exploratory factorial analysis and two confirmatory factorial analyses. In addition, an analysis of invariability by sex and age was carried out. The results reflected that the validated questionnaire showed adequate psychometric properties, being invariable with respect to sex and age.


Subject(s)
Exercise , Physical Education and Training , Adolescent , Humans , Psychometrics , Reproducibility of Results , Spain , Students , Surveys and Questionnaires
8.
Article in English | MEDLINE | ID: mdl-32545626

ABSTRACT

The objective of this study was to analyse the relationship between emotional intelligence and social skills, and how these two variables influence bullying. In this study, 912 Spanish high school students, 471 boys and 441 girls aged 14-16 years, participated, who were administered the Spanish version of the Trait Meta Mood Scale 24, the "Bateria de socialización BAS-3" and the Peer Harassment Questionnaire. To analyse the results, a structural equation model was made. The results reflected a positive relationship between emotional intelligence and social skills (B = 0.44, p < 0.001), and a negative relationship with respect to bullying (B = -0.56, p < 0.001). In turn, social skills reflected a negative relationship with respect to bullying (B = -0.38, p < 0.001). These results reflect the need to implement educational programs focused on the development of emotional intelligence in the classroom, as a means to try to stop bullying behaviours in the classroom.


Subject(s)
Emotional Intelligence , Social Skills , Adolescent , Bullying , Female , Humans , Male , Peer Group , Students
9.
Phys Rev E ; 99(2-1): 023113, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30934232

ABSTRACT

We analyze the effect of a small inclination on the well-studied problem of two-dimensional binary fluid convection in a horizontally extended closed rectangular box with a negative separation ratio, heated from below. The horizontal component of gravity generates a shear flow that replaces the motionless conduction state when inclination is not present. This large-scale flow interacts with the convective currents resulting from the vertical component of gravity. For very small inclinations the primary bifurcation of this flow is a Hopf bifurcation that gives rise to chevrons and blinking states similar to those obtained with no inclination. For larger but still small inclinations this bifurcation disappears and is superseded by a fold bifurcation of the large-scale flow. The convecton branches, i.e., branches of spatially localized states consisting of counterrotating rolls, are strongly affected, with the snaking bifurcation diagram present in the noninclined system destroyed already at small inclinations. For slightly larger but still small inclinations we obtain small-amplitude localized states consisting of corotating rolls that evolve continuously when the primary large-scale flow is continued in the Rayleigh number. These localized states lie on a solution branch with very complex behavior strongly dependent on the values of the system parameters. In addition, several disconnected branches connecting solutions in the form of corotating rolls, counterrotating rolls, and mixed corotating and counterrotating states are also obtained.

10.
Phys Rev E ; 97(2-1): 023108, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29548138

ABSTRACT

This paper reports on numerical investigations of the effect of a slight inclination α on pattern formation in a shallow vertical cylindrical cell heated from below for binary mixtures with a positive value of the Soret coefficient. By using direct numerical simulation of the three-dimensional Boussinesq equations with Soret effect in cylindrical geometry, we show that a slight inclination of the cell in the range α≈0.036rad=2^{∘} strongly influences pattern selection. The large-scale shear flow (LSSF) induced by the small tilt of gravity overcomes the squarelike arrangements observed in noninclined cylinders in the Soret regime, stratifies the fluid along the direction of inclination, and produces an enhanced separation of the two components of the mixture. The competition between shear effects and horizontal and vertical buoyancy alters significantly the dynamics observed in noninclined convection. Additional unexpected time-dependent patterns coexist with the basic LSSF. We focus on an unsual periodic state recently discovered in an experiment, the so-called superhighway convection state (SHC), in which ascending and descending regions of fluid move in opposite directions. We provide numerical confirmation that Boussinesq Navier-Stokes equations with standard boundary conditions contain the essential ingredients that allow for the existence of such a state. Also, we obtain a persistent heteroclinic structure where regular oscillations between a SHC pattern and a state of nearly stationary longitudinal rolls take place. We characterize numerically these time-dependent patterns and investigate the dynamics around the threshold of convection.

11.
Phys Rev E ; 93(6): 063113, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27415364

ABSTRACT

We study the problem of thermal convection in a laterally heated horizontal cylinder rotating about its axis. A cylinder of aspect ratio Γ=H/2R=2 containing a small Prandtl number fluid (σ=0.01) representative of molten metals and molten semiconductors at high temperature is considered. We focus on a slow rotation regime (Ω<8), where the effects of rotation and buoyancy forces are comparable. The Navier-Stokes and energy equations with the Boussinesq approximation are solved numerically to calculate the basic states, analyze their linear stability, and compute several secondary flows originated from the instabilities. Due to the confined cylindrical geometry-the presence of lateral walls and lids-all the flows are completely three dimensional, even the basic steady states. Results characterizing the basic states as the rotation rate increases are presented. As it occurred in the nonrotating case for higher values of the Prandtl number, two curves of steady states with the same symmetric character coexist for moderate values of the Rayleigh number. In the range of Ω considered, rotation has a stabilizing effect only for very small values. As the value of the rotation rate approaches Ω=3.5 and Ω=4.5, the scenario of bifurcations becomes more complex due to the existence in both cases of very close bifurcations of codimension 2, which in the latter case involve both curves of symmetric solutions.

12.
Front Psychol ; 5: 1572, 2014.
Article in English | MEDLINE | ID: mdl-25628591

ABSTRACT

Fibromyalgia is a disabling syndrome. Results obtained with different therapies are very limited to date. The goal of this study was to verify whether the application of a mindfulness-based training program was effective in modifying anger, anxiety, and depression levels in a group of women diagnosed with fibromyalgia. This study is an experimental trial that employed a waiting list control group. Measures were taken at three different times: pretest, posttest, and follow-up. The statistical analyses revealed a significant reduction of anger (trait) levels, internal expression of anger, state anxiety, and depression in the experimental group as compared to the control group, as well as a significant increase in internal control of anger. It can be concluded that the mindfulness-based treatment was effective after 7 weeks. These results were maintained 3 months after the end of the intervention.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(2 Pt 2): 025201, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19792185

ABSTRACT

Binary mixtures with a negative separation ratio are known to exhibit time-independent spatially localized convection when heated from below. Numerical continuation of such states in a closed two-dimensional container with experimental boundary conditions and parameter values reveals the presence of a pinning region in Rayleigh number with multiple stable localized states but no bistability between the conduction state and an independent container-filling state. An explanation for this unusual behavior is offered.

14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(3 Pt 2): 036313, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18517517

ABSTRACT

Pattern selection near the onset of convection in a cylindrical container heated from below is investigated numerically for a water-ethanol mixture, with parameter values and boundary conditions relevant to experiments. The Boussinesq three-dimensional equations for binary fluid convection are simulated for cylinders of aspect ratio Gamma=11 and 10.5 (Gamma identical with R/d, where R is the radius of the cell and d its height). The onset of convection occurs via a subcritical Hopf bifurcation in which the critical mode is strongly influenced by small variations of the aspect ratio of the cell. During the linear regime, an m=1 azimuthal mode consisting of radially traveling waves grows in amplitude in the Gamma=11 cell, while an m=0 azimuthal mode is selected in the Gamma =10.5 cylinder. As convection evolves, simulations for subcritical and supercritical Rayleigh numbers reveal differences in the dynamics. Very close to the critical value, convection is erratic and focuses along one or more diameters of the cell; growths and collapses of the convection amplitude take place, but convection eventually dies away for subcritical values and persists for slightly supercritical values. For larger supercritical values, convection grows progressively in amplitude, and patterns consist of traveling-wave regions of convection initially focused near the cell center, though expanding slowly until a large-amplitude state is reached. Depending on the reduced Rayleigh number, the final state can be a nonsteady state filling the cell or a disordered confined state.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 2): 026310, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17358425

ABSTRACT

Binary convection in large-aspect-ratio annular containers heated from below is studied numerically for a water-ethanol mixture. High-resolution numerical tools based on spectral methods are used to solve the hydrodynamic equations in the two-dimensional approximation. The weakly nonlinear states arising very close to the onset of convection, the strongly nonlinear bursts of amplitude that precede the small-amplitude states, and the dispersive chaotic states encountered further above onset in experiments for mixtures with a weak negative Soret coupling are analyzed in detail in extended domains of aspect ratio 80. Steady localized states surrounded either by quiescent fluid or by small-amplitude waves are also obtained, and the role they play in the dynamics is elucidated.

16.
Phys Rev Lett ; 92(23): 234501, 2004 Jun 11.
Article in English | MEDLINE | ID: mdl-15245161

ABSTRACT

A global bifurcation of the blue sky catastrophe type has been found in a small Prandtl number binary mixture contained in a laterally heated cavity. The system has been studied numerically applying the tools of bifurcation theory. The catastrophe corresponds to the destruction of an orbit which, for a large range of Rayleigh numbers, is the only stable solution. This orbit is born in a global saddle-loop bifurcation and becomes chaotic in a period-doubling cascade just before its disappearance at the blue sky catastrophe.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(1 Pt 2): 016303, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11800780

ABSTRACT

Direct numerical simulations of chevrons, blinking states, and repeated transients in binary fluid mixtures with a negative separation ratio heated from below are described. The calculations are performed in two-dimensional containers using realistic boundary conditions and the parameter values used in the experiments of Kolodner [Phys. Rev. E 47, 1038 (1993)]. Particular attention is paid to the multiplicity of states, and their dependence on the applied Rayleigh number and the aspect ratio of the container. Quantitative agreement with the experiments is obtained, and a mechanism explaining the origin and properties of the repeated transients observed in the experiments is proposed.

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