1,544 research outputs found

    Pharmacological rescue of adult hippocampal neurogenesis in a mouse model of X-linked intellectual disability

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    Oligophrenin-1 (OPHN1) is a Rho GTPase activating protein whose mutations cause X-linked intellectual disability (XLID). How loss of function of Ophnl affects neuronal development is only partly understood. Here we have exploited adult hippocampal neurogenesis to dissect the steps of neuronal differentiation that are affected by Ophn1 deletion. We found that mice lacking Ophnl display a reduction in the number of newborn neurons in the dentate gyrus. A significant fraction of the Ophn1-deficient newly generated neurons failed to extend an axon towards CM, and showed an altered density of dendritic protrusions. Since Ophnl-deficient mice display overactivation of Rho-associated protein kinase (ROCK) and protein kinase A (PICA) signaling, we administered a clinically approved ROCK/PICA inhibitor (fasudil) to correct the neurogenesis defects. While administration of fasudil was not effective in rescuing axon formation, the same treatment completely restored spine density to control levels, and enhanced the long-term survival of adult-born neurons in mice lacking Ophn1. These results identify specific neurodevelopmental steps that are impacted by Ophn1 deletion, and indicate that they may be at least partially corrected by pharmacological treatment. (C) 2017 The Authors. Published by Elsevier Inc

    Workplace Bullying and Post-Traumatic Stress Disorder Symptomology: The Influence of Role Conflict and the Moderating Effects of Neuroticism and Managerial Competencies

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    Research has explored numerous consequences of workplace bullying, including a recent link to the exhibition of post-traumatic stress disorder (PTSD) symptomology. Role conflict as a workplace stressor may contribute to instances of bullying from a passive perspective, which may lead to PTSD symptomology in victims. What remains less explored is if role conflict has a direct relationship to PTSD symptomology and how personality traits such as neuroticism and workplace factors such as managerial competencies may moderate the stress brought on by role conflict. Hence the present study seeks to examine this gap in the literature. This study utilizes a between-subjects, cross-sectional design with 159 participants, 39.6% male and 60.4% female. Most participants (60%) were Italian workers of a large social cooperative organization. Confirmatory factor analysis indicated that the measurement model was valid and had an adequate model fit. Results from two separate moderated mediation analyses found a positive, full mediation between the independent variable of role conflict, the mediator of exposure to bullying, and the dependent variable of PTSD symptomology. Furthermore, in this study, neuroticism strengthened the indirect effect while managerial competencies weakened it. The results highlight the importance of training competent managers and providing resources for more vulnerable employees to moderate employee work stress and its negative outcomes

    Multiple-point statistical simulation for hydrogeological models: 3D training image development and conditioning strategies

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    Most studies about the application of geostatistical simulations based on multiple-point statistics (MPS) to hydrogeological modelling focus on relatively fine-scale models and concentrate on the estimation of facies-level, structural uncertainty. Much less attention is paid to the use of input data and optimal construction of training images. For instance, even though the training image should capture a set of spatial geological characteristics to guide the simulations, the majority of the research still relies on 2D or quasi-3D training images. In the present study, we demonstrate a novel strategy for 3D MPS modelling characterized by: (i) realistic 3D training images, and (ii) an effective workflow for incorporating a diverse group of geological and geophysical data sets. The study covers an area of 2810 km2 in the southern part of Denmark. MPS simulations are performed on a subset of the geological succession (the lower to middle Miocene sediments) which is characterized by relatively uniform structures and dominated by sand and clay. The simulated domain is large and each of the geostatistical realizations contains approximately 45 million voxels with size 100 m × 100 m × 5 m. Data used for the modelling include water well logs, high-resolution seismic data, and a previously published 3D geological model. We apply a series of different strategies for the simulations based on data quality, and develop a novel method to effectively create observed sand/clay spatial trends. The training image is constructed as a small 3D voxel model covering an area of 90 km2. We use an iterative training image development strategy and find that even slight modifications in the training image create significant changes in simulations. Thus, the study underlines that it is important to consider both the geological environment, and the type and quality of input information in order to achieve optimal results from MPS modelling. In this study we present a possible workflow to build the training image and effectively handle different types of input information to perform large-scale geostatistical modellin

    Coping with negative stereotypes toward older workers: Organizational and work-related outcomes

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    The current study aims to test a moderated-mediation model in which occupational selfefficacy determines the indirect effect of negative stereotypes about older workers in the organization both on psychological engagement in the work domain and on attitudes toward development opportunities through identification with the company. The survey involved 1,501 Italian subjects aged over 50 who were employed by a major large-scale retailer. Consistently with the Social Identity Theory and the Social Exchange Theory, results showed that the perception of negative stereotypes about older workers in the organization is associated with low identification with the company and, subsequently, with poor psychological engagement in the work domain and with attitudes indicating very little interest in development opportunities. In addition, this association was found to be stronger in older workers with higher and medium levels of occupational selfefficacy. These findings suggest that organizations should discourage the dissemination of negative stereotypes about older workers in the workplace because they may lead to older workers' disengagement from the work domain and their loss of interest in development opportunities

    A Low Complexity Rolling Bearing Diagnosis Technique Based on Machine Learning and Smart Preprocessing

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    In this work, we present a diagnosis system for rolling bearings that leverages simultaneous measurements of vibrations and machine rotation speed. Our approach combines the robustness of simple time domain methods for fault detection with the potential of machine learning techniques for fault location. This research is based on a neural network classifier, which exploits a simple and novel preprocessing algorithm specifically designed for minimizing the dependency of the classifier performance on the machine working conditions, on the bearing model and on the acquisition system set-up. The overall diagnosis system is based on light algorithms with reduced complexity and hardware resource demand and is designed to be deployed in embedded electronics. The fault diagnosis system was trained using emulated data, exploiting an ad-hoc test bench thus avoiding the problem of generating enough data, achieving an overall classifier accuracy larger than 98%. Its noteworthy ability to generalize was proven by using data emulating different working conditions and acquisition set-ups and noise levels, obtaining in all the cases accuracies greater than 97%, thereby proving in this way that the proposed system can be applied in a wide spectrum of different applications. Finally, real data from an on-line database containing vibration signals obtained in a completely different scenario are used to demonstrate the distinctive capability of the proposed system to generalize

    Gas sensing properties of In2O3 nano-films obtained by low temperature pulsed electron deposition technique on alumina substrates

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    Nanostructured Indium(III) oxide (In2O3) films deposited by low temperature pulsed electron deposition (LPED) technique on customized alumina printed circuit boards have been manufactured and characterized as gas sensing devices. Their electrical properties have monitored directly during deposition to optimize their sensing performance. Experimental results with oxidizing (NO2) as well as reducing (CO) gases in both air and inert gas carriers are discussed and modeled

    Unravelling work drive: A comparison between workaholism and overcommitment

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    Workaholism and overcommitment are often used as interchangeable constructs describing an individual’s over-involvement toward their own job. Employees with high levels in both constructs are characterized by an excessive effort and attachment to their job, with the incapability to detach from it and negative consequences in terms of poor health and job burnout. However, few studies have simultaneously measured both constructs, and their relationships are still not clear. In this study, we try to disentangle workaholism and overcommitment by comparing them with theoretically related contextual and personal antecedents, as well as their health consequences. We conducted a nonprobability mixed mode research design on 133 employees from different organizations in Italy using both self-and other-reported measures. To test our hypothesis that workaholism and overcommitment are related yet different constructs, we used partial correlations and regression analyses. The results confirm that these two constructs are related to each other, but also outline that overcommitment (and not workaholism) is uniquely related to job burnout, so that overcommitment rather than workaholism could represent the true negative aspect of work drive. Additionally, workaholism is more related to conscientiousness than overcommitment, while overcommitment shows a stronger relationship with neuroticism than workaholism. The theoretical implications are discussed
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