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The human tactile system is known to discriminate different types of touches, one of these termed & lsquo;affective touch & rsquo;, is mainly mediated by slow conducting tactile afferents (CT fibres), which are preferentially activated by slow and gentle strokes. Human infants experience self-generated tactile stimulation during prena-tal life, and they receive a large amount of affectionate touches by their caregivers from birth. This early and extended experience with tactile stimulation may likely make infants particularly sensitive to affective touch, and increasing evidence shows that this may indeed be the case. However, infants commonly experience affective touch in the context of social interactions with familiar adults (e.g., while looking at their caregiver), and recent evidence suggests that this helps them assigning affiliative and communicative meaning to the touch they are perceiving. Here we investigated the presence of visual-tactile interactions in 4 & ndash;5-month-old infants & rsquo; physiolog-ical (i.e., skin conductance) and behavioural (i.e., visual looking times) responses to visual and tactile stimulation of affective/social nature when the sources of both stimulation are not familiar to the infant. To explore whether the modulation of physiological arousal elicited by the socially-relevant bimodal stimulation is specific to infants or extends into adulthood, we also tested a group of adults. Infants (N = 25) and adults (N = 25) were stimulated on their forearm through slow stroking (i.e. affective touch) or tapping (i.e. non-affective touch) during the obser-vation of dynamic images of socially-relevant (i.e., an unfamiliar face) and non-socially-relevant (i.e., a house) stimuli. We found that the simultaneous presentation of socially-relevant visual-tactile stimuli significantly decreased infants & rsquo; & ndash; but not the adults & rsquo; & ndash; electrodermal response, suggesting that infants easily int

A new approach to modelling the microstructure evolution and yield strength in laser powder bed fusion components is introduced. Restoration mechanisms such as discontinuous dynamic recrystallization, continuous dynamic recrystallization, and dynamic recovery were found to be activated during laser powder bed fusion of austenitic stainless steels; these are modelled both via classical Zener-Hollomon and thermostatistical approaches. A mechanism is suggested for the formation of dislocation cells from solidification cells and dendrites, and their further transformation to low-angle grain boundaries to form subgrains. This occurs due to dynamic recovery during laser powder bed fusion. The yield strength is successfully modelled via a Hall–Petch-type relationship in terms of the subgrain size, instead of the actual grain size or the dislocation cell size. The validated Hall–Petch-type equation for austenitic stainless steels provides a guideline for the strengthening of laser powder bed fusion alloys with subgrain refinement, via increasing the low-angle grain boundary fraction (grain boundary engineering). To obtain higher strength, dynamic recovery should be promoted as the main mechanism to induce low-angle grain boundaries. The dependency of yield stress on process parameters and alloy composition is quantitatively described.

High blood pressure (BP) and excess weight can lead to early cardiovascular organ damage already in children. Carotid-femoral pulse wave velocity (cf-PWV) is the non-invasive gold standard method for assessing aortic stiffness, while carotid-radial PWV (cr-PWV) provides information on the distensibility of the upper limb arteries. The aim of this study was to evaluate the relationship of BP and BMI z-scores with arterial stiffness and left ventricular mass index (LVMI) in a pediatric population.

Several adult studies have proved the existence of a shared neural circuit in the somatosensory cortices that responds to both the body being touched and the sight of the body being touched. Despite the fundamental role of touch in infancy, the existence of similar visuo-tactile mirroring processes, supporting both felt and seen touch, still needs an in-depth empirical investigation. To this aim, we explored 8-month-olds mu desynchronization over somatosensory sites in response to felt and observed touch in a live experimental setting. EEG desynchronization (6-8 Hz mu frequency range) was measured during three experimental conditions: i) infants were stroked on their right hand by a parent (Touch condition); ii) infants observed a right hand being stroked (Observation Touch condition); iii) infants observed a right hand moving over the left hand without making contact (Action Control condition). Mu desynchronization of somatosensory sites contralateral to the hand being stroked emerged in response to both Touch and Observation Touch conditions, but not in the Action control condition. Further, greater mu desynchronization was found in the Touch and Observation Touch conditions as compared to the Action control condition. Our results highlight the early involvement of a shared somatosensory system, likely supporting infants' understanding of others' tactile sensations.

Hand size perceptual distortions characterize adult human cognition. Notwithstanding the importance of uncovering how hand size representation develops in humans, studies in this field are still at a preliminary stage. Indeed, it is yet to be understood whether hand size distortions are present and reliable in early childhood and whether they differ from adults’ distortions, offering a more in-depth insight into the emergence and development of such representations. We addressed this issue by comparing 4- to 6- year-old children and adults’ representation of their own hand size, as assessed with a 2-forced choice visual perceptual task. To test participants’ ability to estimate their own hand size, children and adults judged whether pictures of their own hand, resized to appear smaller or bigger than their own hand, matched or not its actual dimension. Results show that children aged 4 to 6 years tend to underestimate their own hand size, while adults underestimate their own hand more weakly. This evidence suggests that body-parts perceptual distortions are already in place in early childhood, and thus represent a characteristic of the human body representation.

Combining information across different sensory modalities is of critical importance for the animal's survival and a core feature of human's everyday life. In adulthood, sensory information is often integrated in a statistically optimal fashion, so that the combined estimates of two or more senses are more reliable than the best single one. Several studies have shown that young children use one sense to calibrate the others, which results in unisensory dominance and undermines their optimal multisensory integration abilities. In this study we trained children aged 4–5 years with action-like mini games, to determine whether it could improve their multisensory as well as their visuo-spatial skills. Multisensory integration abilities were assessed using a visuo-haptic size discrimination task, while visuo-spatial attention skills were investigated using a multiple object tracking task (MOT). We found that 2-weeks training were sufficient to observe both optimal multisensory integration and visuo-spatial enhancements selectively in the group trained with action-like mini games. This plastic change persisted up to 3 months, as assessed in a follow-up. Our novel findings reveal that abilities that are commonly known to emerge in late childhood can be promoted in younger children through action-like mini games and have long-lasting effects. Our data have clinical implications, in that they suggest that specific trainings could potentially help children with multisensory integration deficits.

Human societies are organised around cooperative interactions, the origins and development of which have become a timely topic. In this study, we investigated the development of indirect reciprocity in 18–24-month-old toddlers, and infants aged 6 months, on a two-phase sharing task with non-familiar individuals. In the first phase, we observed whether infants and toddlers differentiated and manifested a preference toward an individual altruistically sharing or acting selfishly. In the second phase, infants and toddlers interacted with the same prosocial and antisocial individuals seen in the first phase, and we observed whether they were willing to share with one of the two. Indirect reciprocity was assessed as the match between the preferences for the prosocial individual in phase one, and the first-person sharing in the second phase. Evidence showed that toddlers, but not infants, indirectly reciprocated the prosocial individual, suggesting that understanding of such a complex behaviour as indirect reciprocity may require prolonged experience in order to emerge.

Introduction: Nurses frequently face different events associated with stress, psychosocial factors, and other issues which have impacts on their mental health. Objective: To assess the correlation between psychological demand, work control, social support, psychological stress, and burnout dimensions (illusion for the activity, psychic wear, indolence, guilt), within a model of trajectories among Mexican nurses. Methodology: This is a transversal, observational, and analytical study conducted on a convenience sample of 357 nursing professionals from the state of Morelos, Mexico. Data were gathered using three questionnaires, the Perceived Stress Scale, the Job Content Questionnaire, y el Maslach Burnout Inventory. SPSS 19 and LISREL 8.3 were used to process and model the data. Results: Psychological Stress was specified as the mediating variable of the psychosocial factors and dimensions of burnout within the model of trajectories. Adjustment indexes were acceptable. High levels of social support, work control, and illusion for the activity were found. Moderate degrees of psychological demand and psychological stress were found. Low levels of psychic wear, indolence, and guilt were found. Conclusion: It is recommended to implement effective intervention strategies to maintain nursing personnel within low levels of psychological demand, high levels of work control, high levels of social support, and moderate levels of stress, all these in order to prevent the Syndrome of Burnout., Introdução: O pessoal de enfermagem se enfrenta cotidianamente a diferentes eventos associados ao estresse, fatores psicossociais e outros mecanismos que afetam sua saúde mental. Objetivo: Avaliar a correlação entre a demanda psicológica, o controle laboral, o apoio social, o estresse psicológico, e as dimensões e da Síndrome de Burnout (ilusão pelo trabalho, desgaste psíquico, indolência e culpa), em um modelo de trajetórias em enfermeiras mexicanas. Metodologia: Estudo transversal, observacional, analítico, conduzido em 357 profissionais de enfermagem de Morelos, México, selecionados por conveniência. Os dados foram coletados empregando três questionários, a Escala de Estresse Percebido, o Questionário do Conteúdo do Trabalho e o Questionário para a Avaliação da Síndrome de Burnout no Trabalho. Os programas SPSS 19 e LISREL 8.3 foram empregados para o processamento e modelagem dos dados. Resultados: No modelo de trajetórias, especificou-se como variável mediadora dos fatores psicossociais e das dimensões da Síndrome de Burnout no Trabalho (SQT), ao estresse psicológico. Os índices de ajuste foram aceitáveis. Encontraram-se altos níveis de apoio social, controle laboral e ilusão pelo trabalho; graus moderados de demanda psicológica e estresse psicológico; e baixos níveis de desgaste psíquico, indolência e culpa. Conclusão: Implicações para a disciplina, propõe-se implementar estratégias de intervenção efetivas para manter no pessoal de enfermagem baixos níveis de demandas psicológicas, altos níveis de controle laboral, altos níveis de apoio social, e níveis moderados de estresse, para prevenir, o SQT., Introducción: El personal de enfermería se enfrenta cotidianamente a diferentes eventos asociados al estrés, factores psicosociales y otros mecanismos que afectan su salud mental. Objetivo: Evaluar la correlación entre la demanda psicológica, el control laboral, el apoyo social, el estrés psicológico, y las dimensiones del Síndrome de Burnout (ilusión por el trabajo, desgaste psíquico, indolencia y culpa), en un modelo de trayectorias en enfermeras mexicanas. Metodología: Estudio transversal, observacional, analítico, conducido en 357 profesionales de enfermería de Morelos, México, seleccionados por conveniencia. Los datos fueron colectados empleando tres cuestionarios, la Escala de Estrés Percibido, el Cuestionario del Contenido del Trabajo y el Cuestionario para la Evaluación del Síndrome de Quemarse por el Trabajo. Los programas SPSS 19 y LISREL 8.3 fueron empleados para el procesamiento y modelaje de los datos. Resultados: En el modelo de trayectorias, se especificó como variable mediadora de los factores psicosociales y de las dimensiones del Síndrome de Quemarse por el Trabajo (SQT), al estrés psicológico. Los índices de ajuste fueron aceptables. Se encontraron altos niveles de apoyo social, control laboral e ilusión por el trabajo; grados moderados de demanda psicológica y estrés psicológico; y bajos niveles de desgaste psíquico, indolencia y culpa. Conclusión: Implicaciones para la disciplina, se propone implementar estrategias de intervención efectivas para mantener en el personal de enfermería bajos niveles de demandas psicológicas, altos niveles de control laboral, altos niveles de apoyo social, y niveles moderados de estrés, para prevenir, el SQT.

OBJECTIVE AND METHODS: The study aimed at evaluating, in a large sample of Italian children, the reclassification of blood pressure categories with the new U.S. nomograms, obtained in a population of normal-weight children (American Academy of Pediatrics Clinical Practice Guidelines, AAP-CPG), compared with the Fourth Report/European Society of Hypertension (ESH) nomograms. The performance of the two classifications in identifying the presence of left ventricular hypertrophy was also assessed. RESULTS: In 951 individuals referred to a Pediatric Center for Cardiovascular Risk Prevention, a 12% increase in the prevalence of children with blood pressure at least 90th percentile was observed by using the new nomograms. In the subsample of children aged at least 13 years, the application of the blood pressure fixed cutoff values of 120/<80 mmHg (for 'elevated' blood pressure) and of 130/80 mmHg (for hypertension) led to a change in the blood pressure category (worse or better) in about 30% of cases as compared with the AAP-CPG classification based on percentiles. Regarding the identification of individuals with left ventricular hypertrophy, the AAP-CPG classification led to an increase in the true positive fraction (sensitivity) of 5.5%, and to an increment of the false-positive fraction (1 - specificity) of 5.8%. The logistic regression model, adjusted for possible confounding factors, and the ROC curves obtained from the linear predictor of the model showed an identical performance of the Fourth Report/ESH and the AAP-CPG classifications. CONCLUSION: In our paediatric population, the AAP-CPG classification slightly increased the prevalence of elevated blood pressure values compared with the Fourth Report/ESH classification. Moreover, the application of more 'physiological' nomograms, based on a population of normal-weight children, did not yield any advantage in identifying individuals with early cardiac organ damage