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To explain irradiation creep, several mechanisms have been proposed. Some are based on the effect of stress on either nucleation or growth of dislocation loops. To investigate these mechanisms in aluminum we combine in-situ transmission electron microscope irradiation under stress and two simulation approaches (object kinetic Monte-Carlo, molecular dynamics Frenkel pair accumulation). We observe the selectivity of Frank loop variants under electron irradiation and applied stress. When the stress is turned on after loop formation, there is no loop variant selectivity, suggesting the absence of preferential absorption on already formed loops. Object kinetic Monte-Carlo simulations, including the effect of stress on the diffusion of point defects, show no growth rate difference between loop variants. Frenkel pair accumulation simulations exhibit variant selectivity of nucleated loops. This shows that loop selectivity is due to preferential nucleation of well oriented loops under stress and not to differential growth of loops. [ABSTRACT FROM AUTHOR]

[Display omitted] We investigate the influence of elastic properties of point defects on dislocation climb under stress and irradiation. For this purpose, elastic dipole tensors and diaelastic polarizabilities are evaluated in aluminum for vacancies and self-interstitial atoms in their stable and saddle configurations, using density functional theory calculations. These parameters are introduced in an object kinetic Monte-Carlo code and a continuous diffusion model to estimate the stress dependence of dislocation climb, using a dipole of straight dislocations. We show that both parameters have an influence on absorption of point defects under stress, in agreement with previous analytical models. However, the effect of dipole tensor is found only 5 times larger than polarizability, whereas models predict a factor up to 30. In addition, including polarizability reverses the stress angular dependence when a uniaxial stress is applied orthogonal to the dislocation line, so in general polarizability cannot be ignored for simulations under applied stress. Further comparison with analytical models shows that they give a good description of angular dependence, provided saddle point configuration of point defects is not too anisotropic. For vacancies, which are strongly anisotropic in their saddle configuration, models fail to reproduce quantitatively lattice effects on stress angular dependence observed in simulations. Calculations show that dislocation climb velocity under irradiation is expected to be the highest if the stress is approximately orthogonal to the dislocation line, especially along the Burgers vector, and the lowest if the stress is applied close to the 〈 100 〉 direction with the largest projection on the dislocation line. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The primary aim of this study was to compare the sleep macroarchitecture of children and adolescents whose mothers have a history of depression with children and adolescents whose mothers do not. Method: Polysomnography (PSG) and Holter electroencephalogram (EEG) were used to compare the sleep architecture of 35 children whose mothers had at least one previous depressive episode (19 boys, aged 4–18years, “high-risk” group) and 25 controls (13 males, aged 4–18years, “low-risk” group) whose mothers had never had a depressive episode. The total sleep time, wakefulness after sleep onset (WASO), sleep latency, sleep efficiency, number of awakenings per hour of sleep, percentages of time spent in each sleep stage, rapid eye movement (REM) latency and the depressive symptoms of participants were measured. Results: In children (4–12years old), the high-risk group exhibited significantly more depressive symptoms than controls (P =0.02). However, PSG parameters were not significantly different between high-risk children and controls. In adolescents (13–18years old), the high-risk subjects presented with significantly more depressive symptoms (P =0.003), a significant increase in WASO (P =0.019) and a significant decrease in sleep efficiency compared to controls (P =0.009). Conclusion: This study shows that children and adolescents born from mothers with a history of at least one depressive episode had significantly more depressive symptoms than controls. However, only high-risk adolescents presented with concurrent alterations of sleep macroarchitecture. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to determine whether the implicit theory effect extends to children with oppositional defiant disorder (ODD), with academic difficulties. Twenty-five male children, aged 8–11 years with ODD were randomly assigned to one of two experimental conditions (Incremental Theory highlighting the possibility of self-improvement vs. control). An increase of cognitive performance (IQ) was found for children with ODD in the incremental condition, but not in the control condition. This cognitive improvement could be viewed as a protective factor for children and adolescents with ODD on academic setting. [Copyright &y& Elsevier]

Abstract: During the past decade, several studies have reported positive effects of cognitive-behavioral therapy (CBT) in the treatment of children and adolescents with mental disorders. One of the most important CBT interventions is to teach children and adolescents to challenge negative thoughts that lead to maladjusted behaviors. Based on the implicit theories of intelligence framework, the main purpose of this study was to test whether an incremental theory manipulation could be used to affect IQ test performance in adolescents with Generalized Anxiety Disorder (GAD). Results showed that patients demonstrated enhanced IQ performance and experienced less state anxiety when they were exposed to an incremental theory of intelligence manipulation. Our findings suggest that incremental theory manipulation provides a useful cognitive strategy for addressing school-related anxiety in adolescents with mental disorders such as GAD. [Copyright &y& Elsevier]

Notre objectif principal était de décrire les caractéristiques des actes auto-agressifs avec substance des sujets de moins de 18 ans pris en charge dans le cadre de la régulation téléphonique d'urgence du centre antipoison et de toxicovigilance de Marseille. Cette étude est descriptive, prospective et quantitative. Elle est monocentrique et a été réalisée au sein du centre antipoison et de toxicovigilance de Marseille. Elle a inclus l'ensemble des sujets de moins de 18 ans pour lesquels un avis au centre antipoison et de toxicovigilance de Marseille a été sollicité au décours d'un acte auto-agressif avec une substance toxique (dont des médicaments) entre le 1er octobre 2021 et le 31 janvier 2022. Les 308 sujets inclus étaient âgés de 11 à 17 ans avec un âge moyen de 14,9 ans (±1,5) pour les filles et 14,6 (±1,7) pour les garçons (p = 0,234). Le sex-ratio était de 0,14. Deux cent quarante patients (77,9 %) avaient déjà un suivi antérieur psychologique ou psychiatrique. Il s'agissait d'une récidive de tentative de suicide dans 43,8 % des cas (n = 135). Le recours aux services des urgences était quasiment systématique (n = 277, 89,9 %). Il s'agissait en majorité de mono-intoxications (n = 193, 62,7 %). Les intoxications étaient dans la plupart des cas médicamenteuses (n = 281, 91,2 %). Les antalgiques-antipyrétiques étaient la classe médicamenteuse la plus utilisée (n = 147 patients, 47,7 %), suivis par les anxiolytiques (n = 62, 20,1 %). Le paracétamol s'est avéré la substance la plus ingérée (n = 108, 35,1 %). Cent six patients sont restés asymptomatiques (34,4 %). Sur les 308 sujets inclus, 78,6 % étaient hospitalisés pour une durée moyenne de 4 ans jours. Deux cent quarante-neuf jeunes (80,8 %) avaient eu au moins un avis psychiatrique et 200 (64,9 %) avaient un rendez-vous pour une consultation psychiatrique à la sortie. Les caractéristiques démographiques des jeunes suicidants et celles de l'intoxication étaient globalement similaires à celles retrouvées dans la littérature. Le taux de récidive est plus élevé que dans la littérature. Plus de deux ans après le début de la pandémie de SARS-CoV-2, le mal-être de la jeunesse est toujours là alors que l'offre de soin est déjà saturée. Pour inverser la tendance d'ici 2027, le ministère de la Santé et de la Prévention a actualisé sa stratégie nationale de prévention par différents moyens. Une étude au décours pourrait être intéressante pour voir l'impact de ces mesures. Cette étude, même limitée dans le temps et l'espace, complète d'autres indicateurs peu nombreux et partiels, et montre que la crise de santé mentale pédiatrique s'aggrave, en particulier chez les plus jeunes adolescents, avec un taux de récidive qui augmente. Il faut rester vigilant et continuer à mettre en place des actions de dépistage et des moyens de prévention notamment des récidives. To describe poison exposures in case of self-poisoning subjects younger than 18 years old reported to the Marseille Poison Control Center. This is a descriptive, monocentric and prospective review of self-poisoning patients aged < 18 years who reported to the Marseille Poison Control Center from 1st October 2021 to 31st January 2022. The 308 subjects included were aged 11 to 17 years with an average age of 14.9 years (±1.5) for girls and 14.6 (±1.7) for boys (P = 0.234). The sex ratio was 0.14. Two hundred and forty patients (77.9%) already had prior psychological or psychiatric follow-up. It was a recurrence of suicide attempts in 43.8% of cases (n = 135). The use of an emergency department was almost systematic (n = 277, 89.9%). Most of these were mono-intoxications (n = 193, 62.7%). The poisonings were in most cases drug-induced (n = 281, 91.2%). Analgesics-antipyretics were the most used drug class (n = 147 patients, 47.7%), followed by anxiolytics (n = 62, 20.1%). Paracetamol proved to be the most ingested substance (n = 108, 35.1%). One hundred and six patients remained asymptomatic (34.4%). Of the 308 cases included, 78.6% were hospitalized for an average of four days. Two hundred forty-nine cases (80.8%) had one psychiatric evaluation in an emergency department and 200 (64.9%) will have an appointment for a psychiatric consultation on discharge. The demographic characteristics of young suicides and those of intoxication were globally like those found in the literature although our recurrence rate was higher than those in the literature. More than two years after the start of the SARS-CoV-2 pandemic, the malaise of young people remains while the care offer is already saturated. To reverse the trend by 2027 the French Ministry of Health and Prevention has updated its national prevention strategy by various means. A subsequent study could be interesting to see the impact of these measures. This study is limited but seems to complement some indicators, which shows that the pediatric mental health crisis is worsening, especially among the youngest adolescents who have an increased recurrence rate. We must remain vigilant and continue to implement screening actions and means of prevention, particularly of recurrences. [ABSTRACT FROM AUTHOR]

Attention-deficit/hyperactivity disorder (ADHD) was initially considered as a childhood psychiatric disorder. However, longitudinal observations have revealed that ADHD symptoms may persist in adulthood among approximately 50% of the patients [1] . Adult ADHD is associated with impaired social outcome and frequent comorbidities such as mood disorders, personality disorders, and substance use disorders [2,3] . Correctly identifying and treating ADHD can significantly improve the global functioning and cognition of adult subjects, and reduce the intensity and frequency of the comorbid states [2,3] . Nonetheless, the clinical features of adult ADHD are clearly different from the youth form [1,2] , and ADHD symptoms are easily mixed up in adults with symptoms of the comorbid conditions [2,3] . These clinical intricacies can make the diagnosis of ADHD difficult in adults. Moreover, the management of methylphenidate in adult subjects is also associated with specific risks and pitfalls, such as abuse and tampering behaviors, and additional safety risks [4] . Put together, it appears crucial to identify and treat ADHD in adults, but the clinical and therapeutic complexities of adult ADHD require improved expertise and caution from adult psychiatrists and addiction specialists. In this thematic session of the 2015 French Psychiatry Congress, three French leading experts of adult ADHD will address the aforementioned clinical and therapeutic issues of the adulthood form of this disorder. David Da Fonseca, professor of child psychiatry in Marseille, will disentangle the clinical features of adult ADHD from the typical symptoms observed in the youth form. Mélina FATSEAS, associate professor of psychiatry and addiction medicine in Bordeaux, will specifically focus on the many and complex relationships observed between adult ADHD and substance use disorders. Last, Nicolas Simon, professor of addiction medicine and psychopharmacology in Marseille, will synthesize what are the very risks and issues with prescribing methylphenidate in adults. [ABSTRACT FROM AUTHOR]

Purpose: The service configuration with distinct child and adolescent mental health services (CAMHS) and adult mental health services (AMHS) may be a barrier to continuity of care. Because of a lack of transition policy, CAMHS clinicians have to decide whether and when a young person should transition to AMHS. This study describes which characteristics are associated with the clinicians' advice to continue treatment at AMHS. Methods: Demographic, family, clinical, treatment, and service-use characteristics of the MILESTONE cohort of 763 young people from 39 CAMHS in Europe were assessed using multi-informant and standardized assessment tools. Logistic mixed models were fitted to assess the relationship between these characteristics and clinicians' transition recommendations. Results: Young people with higher clinician-rated severity of psychopathology scores, with self- and parent-reported need for ongoing treatment, with lower everyday functional skills and without self-reported psychotic experiences were more likely to be recommended to continue treatment. Among those who had been recommended to continue treatment, young people who used psychotropic medication, who had been in CAMHS for more than a year, and for whom appropriate AMHS were available were more likely to be recommended to continue treatment at AMHS. Young people whose parents indicated a need for ongoing treatment were more likely to be recommended to stay in CAMHS. Conclusion: Although the decision regarding continuity of treatment was mostly determined by a small set of clinical characteristics, the recommendation to continue treatment at AMHS was mostly affected by service-use related characteristics, such as the availability of appropriate services. [ABSTRACT FROM AUTHOR]

A new tuberculosis vaccine is urgently needed. Prime-boost strategies are considered very promising and the inclusion of BCG is highly desirable. In this investigation, we tested the protective efficacy of BCG delivered in the neonatal period followed by boosters in the adult phase with a DNA vaccine containing the hsp65 gene from Mycobacterium leprae (pVAXhsp65). Immune responses were characterized by serum anti-hsp65 antibody levels and IFN-γ and IL-5 production by the spleen. Amounts of these cytokines were also determined in lung homogenates. Protective efficacy was established by the number of colony-forming units (CFU) and histopathological analysis of the lungs after challenge with Mycobacterium tuberculosis. Immunization with BCG alone triggered a significant reduction of CFU in the lungs and also clearly preserved the pulmonary parenchyma. BCG priming also increased the immunogenicity of pVAXhsp65. However, boosters with pVAXhsp65 or the empty vector abolished the protective efficacy of BCG. Also, higher IL-5 levels were produced by spleen and lungs after DNA boosters. These results demonstrated that neonatal BCG immunization followed by DNAhsp65 boosters is highly immunogenic but is not protective against tuberculosis. [ABSTRACT FROM AUTHOR]

Investigates the influence of the trichotomous achievement goal model on intrinsic motivation. Use of the achievement goal approach in achievement motivation; Definition of achievement goals; Comparison between performance-approach and performance-avoidance.