322 research outputs found

    Designing Sugaropolis:digital games as a medium for conveying transnational narratives

    Get PDF
    In this paper, the authors present a case study of ‘Sugaropolis’: a two-year practice-based project that involved interdisciplinary co-design and stakeholder evaluation of two digital game prototypes. Drawing on the diverse expertise of the research team (game design and development, human geography, and transnational narratives), the paper aims to contribute to debates about the use of digital games as a medium for representing the past. With an emphasis on design-as-research, we consider how digital games can be (co-)designed to communicate complex histories and geographies in which people, objects, and resources are connected through space and time

    Sexually Dimorphic Effects of Prenatal Stress on Cognition, Hormonal Responses, and Central Neurotransmitters

    Get PDF
    Exposure to stress during gestation results in physiological and behavioral alterations that persist into adulthood. This study examined the effects of prenatal stress on the postnatal expression of sexually differentiated cognitive, hormonal, and neurochemical profiles in male and female rats. Pregnant dams were subjected to restraint stress three times daily for 45 min during d 14-21 of pregnancy. The offspring of control and prenatally stressed dams were tested for anxiety-related and cognitive behaviors, stress and gonadal steroid hormone levels, as well as monoamines and metabolite levels in selected brain regions. Postnatal testosterone levels (measured at 1 and 5 d) did not differ between controls and prenatally stressed animals. In adulthood, the serum corticosterone response to stress was attenuated in prenatally stressed females, eliminating the sex difference normally observed in this parameter. Prenatally stressed females exhibited higher anxiety levels, evidenced by longer open field entry latencies. Prenatal stress had no effect on object recognition memory, but eliminated the advantage normally seen in the male performance of a spatial memory task. Neurochemical profiles of prenatally stressed females were altered toward the masculine phenotype in the prefrontal cortex, amygdala, and hippocampus. Thus, prenatal stress altered subsequent cognitive, endocrine, and neurochemical responses in a sex-specific manner. These data reinforce the view that prenatal stress affects multiple aspects of brain development, interfering with the expression of normal behavioral, neuroendocrine, and neurochemical sex differences. These data have implications for the effects of prenatal stress on the development of sexually dimorphic endocrine and neurological disorders

    Torsional Force Microscopy of Van der Waals Moir\'es and Atomic Lattices

    Full text link
    In a stack of atomically-thin Van der Waals layers, introducing interlayer twist creates a moir\'e superlattice whose period is a function of twist angle. Changes in that twist angle of even hundredths of a degree can dramatically transform the system's electronic properties. Setting a precise and uniform twist angle for a stack remains difficult, hence determining that twist angle and mapping its spatial variation is very important. Techniques have emerged to do this by imaging the moir\'e, but most of these require sophisticated infrastructure, time-consuming sample preparation beyond stack synthesis, or both. In this work, we show that Torsional Force Microscopy (TFM), a scanning probe technique sensitive to dynamic friction, can reveal surface and shallow subsurface structure of Van der Waals stacks on multiple length scales: the moir\'es formed between bilayers of graphene and between graphene and hexagonal boron nitride (hBN), and also the atomic crystal lattices of graphene and hBN. In TFM, torsional motion of an AFM cantilever is monitored as the it is actively driven at a torsional resonance while a feedback loop maintains contact at a set force with the surface of a sample. TFM works at room temperature in air, with no need for an electrical bias between the tip and the sample, making it applicable to a wide array of samples. It should enable determination of precise structural information including twist angles and strain in moir\'e superlattices and crystallographic orientation of VdW flakes to support predictable moir\'e heterostructure fabrication.Comment: 28 pages, 14 figures including supplementary material

    Symptom profile of postpartum and non-postpartum manic episodes in bipolar I disorder: a within-subjects study

    Get PDF
    The relationship of postpartum mania to episodes of mania occurring outside the perinatal period among women with bipolar disorder remains controversial. Previous studies have used between-subjects designs to compare the clinical presentations of these episodes meaning the differences, in part, may reflect between-group differences. To overcome this we have undertaken within-subject comparisons of the symptom profile of postpartum and non-postpartum manic episodes in 50 women with DSM-IV bipolar I disorder. For each woman detailed symptom information on a postpartum episode of mania and a comparison non-postpartum manic episode was collected. The occurrence of manic, psychotic and depressive symptoms in these episodes were compared. Postpartum manic episodes had a significantly higher incidence of perplexity and excessive self-reproach. Classic manic symptoms, specifically pressured speech and increased sociability, were significantly less frequent in postpartum manic episodes. Overall there were significantly fewer manic symptoms and significantly more depressive symptoms in the postpartum episodes than in the non-postpartum episodes. The mixed presentation of postpartum manic episodes suggests childbirth may act as a pathoplastic trigger in women with bipolar disorder. The differences in symptom profiles suggests further research is warranted into whether differences in treatment response exist among women experiencing postpartum and non-postpartum manic episodes

    Self-directed learning research and its impact on educational practice

    Get PDF
    This scholarly book is the third volume in an NWU book series on self-directed learning and is devoted to self-directed learning research and its impact on educational practice. The importance of self-directed learning for learners in the 21st century to equip themselves with the necessary skills to take responsibility for their own learning for life cannot be over emphasised. The target audience does not only consist of scholars in the field of self-directed learning in Higher Education and the Schooling sector but includes all scholars in the field of teaching and learning in all education and training sectors. The book contributes to the discourse on creating dispositions towards self-directed learning among all learners and adds to the latest body of scholarship in terms of self-directed learning. Although from different perspectives, all chapters in the book are closely linked together around self-directed learning as a central theme, following on the work done in Volume 1 of this series (Self-Directed Learning for the 21st Century: Implications for Higher Education) to form a rich knowledge bank of work on self-directed learning

    Visual Performance Fields: Frames of Reference

    Get PDF
    Performance in most visual discrimination tasks is better along the horizontal than the vertical meridian (Horizontal-Vertical Anisotropy, HVA), and along the lower than the upper vertical meridian (Vertical Meridian Asymmetry, VMA), with intermediate performance at intercardinal locations. As these inhomogeneities are prevalent throughout visual tasks, it is important to understand the perceptual consequences of dissociating spatial reference frames. In all studies of performance fields so far, allocentric environmental references and egocentric observer reference frames were aligned. Here we quantified the effects of manipulating head-centric and retinotopic coordinates on the shape of visual performance fields. When observers viewed briefly presented radial arrays of Gabors and discriminated the tilt of a target relative to homogeneously oriented distractors, performance fields shifted with head tilt (Experiment 1), and fixation (Experiment 2). These results show that performance fields shift in-line with egocentric referents, corresponding to the retinal location of the stimulus

    Smaller total and subregional cerebellar volumes in posttraumatic stress disorder:a mega-analysis by the ENIGMA-PGC PTSD workgroup

    Get PDF
    Although the cerebellum contributes to higher-order cognitive and emotional functions relevant to posttraumatic stress disorder (PTSD), prior research on cerebellar volume in PTSD is scant, particularly when considering subregions that differentially map on to motor, cognitive, and affective functions. In a sample of 4215 adults (PTSD n = 1642; Control n = 2573) across 40 sites from the ENIGMA-PGC PTSD working group, we employed a new state-of-the-art deep-learning based approach for automatic cerebellar parcellation to obtain volumetric estimates for the total cerebellum and 28 subregions. Linear mixed effects models controlling for age, gender, intracranial volume, and site were used to compare cerebellum volumes in PTSD compared to healthy controls (88% trauma-exposed). PTSD was associated with significant grey and white matter reductions of the cerebellum. Compared to controls, people with PTSD demonstrated smaller total cerebellum volume, as well as reduced volume in subregions primarily within the posterior lobe (lobule VIIB, crus II), vermis (VI, VIII), flocculonodular lobe (lobule X), and corpus medullare (all p -FDR &lt; 0.05). Effects of PTSD on volume were consistent, and generally more robust, when examining symptom severity rather than diagnostic status. These findings implicate regionally specific cerebellar volumetric differences in the pathophysiology of PTSD. The cerebellum appears to play an important role in higher-order cognitive and emotional processes, far beyond its historical association with vestibulomotor function. Further examination of the cerebellum in trauma-related psychopathology will help to clarify how cerebellar structure and function may disrupt cognitive and affective processes at the center of translational models for PTSD.</p

    Smaller total and subregional cerebellar volumes in posttraumatic stress disorder:a mega-analysis by the ENIGMA-PGC PTSD workgroup

    Get PDF
    Although the cerebellum contributes to higher-order cognitive and emotional functions relevant to posttraumatic stress disorder (PTSD), prior research on cerebellar volume in PTSD is scant, particularly when considering subregions that differentially map on to motor, cognitive, and affective functions. In a sample of 4215 adults (PTSD n = 1642; Control n = 2573) across 40 sites from the ENIGMA-PGC PTSD working group, we employed a new state-of-the-art deep-learning based approach for automatic cerebellar parcellation to obtain volumetric estimates for the total cerebellum and 28 subregions. Linear mixed effects models controlling for age, gender, intracranial volume, and site were used to compare cerebellum volumes in PTSD compared to healthy controls (88% trauma-exposed). PTSD was associated with significant grey and white matter reductions of the cerebellum. Compared to controls, people with PTSD demonstrated smaller total cerebellum volume, as well as reduced volume in subregions primarily within the posterior lobe (lobule VIIB, crus II), vermis (VI, VIII), flocculonodular lobe (lobule X), and corpus medullare (all p -FDR &lt; 0.05). Effects of PTSD on volume were consistent, and generally more robust, when examining symptom severity rather than diagnostic status. These findings implicate regionally specific cerebellar volumetric differences in the pathophysiology of PTSD. The cerebellum appears to play an important role in higher-order cognitive and emotional processes, far beyond its historical association with vestibulomotor function. Further examination of the cerebellum in trauma-related psychopathology will help to clarify how cerebellar structure and function may disrupt cognitive and affective processes at the center of translational models for PTSD.</p
    • …
    corecore