1,350 research outputs found

    Spatial, seasonal and climatic predicitve models of Rift Valley Fever disease across Africa

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    Understanding the emergence and subsequent spread of human infectious diseases is a critical global challenge, especially for high-impact zoonotic and vector-borne diseases. Global climate and land-use change are likely to alter host and vector distributions, but understanding the impact of these changes on the burden of infectious diseases is difficult. Here, we use a Bayesian spatial model to investigate environmental drivers of one of the most important diseases in Africa, Rift Valley fever (RVF). The model uses a hierarchical approach to determine how environmental drivers vary both spatially and seasonally, and incorporates the effects of key climatic oscillations, to produce a continental risk map of RVF in livestock (as a proxy for human RVF risk). We find RVF risk has a distinct seasonal spatial pattern influenced by climatic variation, with the majority of cases occurring in South Africa and Kenya in the first half of an El Niño year. Irrigation, rainfall and human population density were the main drivers of RVF cases, independent of seasonal, climatic or spatial variation. By accounting more subtly for the patterns in RVF data, we better determine the importance of underlying environmental drivers, and also make space- and time-sensitive predictions to better direct future surveillance resources. This article is part of the themed issue ‘One Health for a changing world: zoonoses, ecosystems and human well-being’

    MIUS integration and subsystems test program

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    The MIUS Integration and Subsystems Test (MIST) facility at the Lyndon B. Johnson Space Center was completed and ready in May 1974 for conducting specific tests in direct support of the Modular Integrated Utility System (MIUS). A series of subsystems and integrated tests was conducted since that time, culminating in a series of 24-hour dynamic tests to further demonstrate the capabilities of the MIUS Program concepts to meet typical utility load profiles for a residential area. Results of the MIST Program are presented which achieved demonstrated plant thermal efficiencies ranging from 57 to 65 percent

    Imaging of z~2 QSO host galaxies with the Hubble Space Telescope

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    We report on deep imaging in 2 filters with the PC2 camera of HST, of five QSOs at redshift ~2, with a range of optical and radio luminosity. The observations included a suite of PSF observations which were used to construct new PSF models, described elsewhere by Dumont et al. The new PSF models were used to remove the QSO nucleus from the images. We find that the host galaxies have resolved flux of order 10% of the QSO nuclei, and are generally luminous and blue, indicating active star-formation. While most have clearly irregular morphologies, the bulk of the flux can be modelled approximately by an r**1/4 law. However, all host galaxies also have an additional approximately exponential luminosity profile beyond a radius about 0.8 arcsec, as also seen in ground-based data with larger telescopes. The QSOs all have a number of nearby faint blue companions which may be young galaxies at the QSO redshift. We discuss implications for evolution of the host galaxies, their spheroidal populations, and central black holes.Comment: 18 pages including 2 tables; to appear in A

    The Impact of Augmented Information on Visuo-Motor Adaptation in Younger and Older Adults

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    BACKGROUND: Adjustment to a visuo-motor rotation is known to be affected by ageing. According to previous studies, the age-related differences primarily pertain to the use of strategic corrections and the generation of explicit knowledge on which strategic corrections are based, whereas the acquisition of an (implicit) internal model of the novel visuo-motor transformation is unaffected. The present study aimed to assess the impact of augmented information on the age-related variation of visuo-motor adjustments. METHODOLOGY/PRINCIPAL FINDINGS: Participants performed aiming movements controlling a cursor on a computer screen. Visual feedback of direction of cursor motion was rotated 75 degrees relative to the direction of hand motion. Participants had to adjust to this rotation in the presence and absence of an additional hand-movement target that explicitly depicted the input-output relations of the visuo-motor transformation. An extensive set of tests was employed in order to disentangle the contributions of different processes to visuo-motor adjustment. Results show that the augmented information failed to affect the age-related variations of explicit knowledge, adaptive shifts, and aftereffects in a substantial way, whereas it clearly affected initial direction errors during practice and proprioceptive realignment. CONCLUSIONS: Contrary to expectations, older participants apparently made no use of the augmented information, whereas younger participants used the additional movement target to reduce initial direction errors early during practice. However, after a first block of trials errors increased, indicating a neglect of the augmented information, and only slowly declined thereafter. A hypothetical dual-task account of these findings is discussed. The use of the augmented information also led to a selective impairment of proprioceptive realignment in the younger group. The mere finding of proprioceptive realignment in adaptation to a visuo-motor rotation in a computer-controlled setup is noteworthy since visual and proprioceptive information pertain to different objects

    Star formation history in the SMC: the case of NGC602

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    Deep HST/ACS photometry of the young cluster NGC 602, located in the remote low density "wing" of the Small Magellanic Cloud, reveals numerous pre-main sequence stars as well as young stars on the main sequence. The resolved stellar content thus provides a basis for studying the star formation history into recent times and constraining several stellar population properties, such as the present day mass function, the initial mass function and the binary fraction. To better characterize the pre-main sequence population, we present a new set of model stellar evolutionary tracks for this evolutionary phase with metallicity appropriate for the Small Magellanic Cloud (Z = 0.004). We use a stellar population synthesis code, which takes into account a full range of stellar evolution phases to derive our best estimate for the star formation history in the region by comparing observed and synthetic color-magnitude diagrams. The derived present day mass function for NGC 602 is consistent with that resulting from the synthetic diagrams. The star formation rate in the region has increased with time on a scale of tens of Myr, reaching 0.30.7×103Myr10.3-0.7 \times 10^{-3} M_\odot yr^{-1} in the last 2.5 Myr, comparable to what is found in Galactic OB associations. Star formation is most complete in the main cluster but continues at moderate levels in the gas-rich periphery of the nebula.Comment: 24 pages. Accepted for publication in A

    Foreign direct investment and investment environment in Dongguan Municipality of southern China

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    Based on 26 case studies, this paper investigates the socio-economic causes of the inflow of FDI and its policy implications in Dongguan. The favourable factors for foreign investors in Dongguan can be categorised under the Dunning's OLI (ownership, locational and internalisation advantages) framework. This paper argues that factors other than policy incentive, such as sub-contractual and pseudo integration, are playing more important roles in attracting the inflow of FDI and maintaining the high level of economic growth in Dongguan. This finding questions the effectiveness of policy incentives, such as tax-breaks, implemented by the Government as a means to attract FDI in Dongguan. The existence of 'Chinese crony capitalism' calls for further improvement in the implementation of laws and regulations in Dongguan and the reduction of bureaucratic red-tape by the central and local governments

    Long Lasting Egocentric Disorientation Induced by Normal Sensori-Motor Spatial Interaction

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    Perception of the cardinal directions of the body, right-left, up-down, ahead-behind, which appears so absolute and fundamental to the organisation of behaviour can in fact, be modified. Perhaps unsurprisingly, it has been shown that prolonged distorted perception of the orientation of body axes can be a consequence of disordered sensori-motor signals, including long-term prismatic adaptation and lesions of the central nervous system. We report the novel and surprising finding that a long-lasting distortion of perception of personal space can also be induced by an ecological pointing task without the artifice of distorting normal sensori-motor relationships.Twelve right-handed healthy adults performed the task of pointing with their arms, without vision, to indicate their subjective 'straight ahead', a task often used to assess the Egocentric Reference. This was performed before, immediately, and one day after a second task intended to 'modulate' perception of spatial direction. The 'modulating' task lasted 5 minutes and consisted of asking participants to point with the right finger to targets that appeared only in one (right or left) half of a computer screen. Estimates of the 'straight-ahead' during pre-test were accurate (inferior to 0.3 degrees deviation). Significantly, up to one day after performing the modulating task, the subjective 'straight-ahead' was deviated (by approximately 3.2 degrees) to the same side to which subjects had pointed to targets.These results reveal that the perception of directional axes for behaviour is readily influenced by interactions with the environment that involve no artificial distortion of normal sensori-motor-spatial relationships and does not necessarily conform to the cardinal directions as defined by the anatomy of orthostatic posture. We thus suggest that perceived space is a dynamic construction directly dependent upon our past experience about the direction and/or the localisation of our sensori-motor spatial interaction with environment

    What we talk about when we talk about "global mindset": managerial cognition in multinational corporations

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    Recent developments in the global economy and in multinational corporations have placed significant emphasis on the cognitive orientations of managers, giving rise to a number of concepts such as “global mindset” that are presumed to be associated with the effective management of multinational corporations (MNCs). This paper reviews the literature on global mindset and clarifies some of the conceptual confusion surrounding the construct. We identify common themes across writers, suggesting that the majority of studies fall into one of three research perspectives: cultural, strategic, and multidimensional. We also identify two constructs from the social sciences that underlie the perspectives found in the literature: cosmopolitanism and cognitive complexity and use these two constructs to develop an integrative theoretical framework of global mindset. We then provide a critical assessment of the field of global mindset and suggest directions for future theoretical and empirical research

    Ambicultural blending between Eastern and Western paradigms : fresh perspectives for international management research

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    East and Southeast Asian worldviews are distinctly different from those of the West. Westerners and Asians construct their environments differently, not least because they construct the notion of \u27self\u27 very differently. This paper describes and exemplifies distinctions in cognitive and linguistic styles between the East and the West and outlines the implications of these styles for environmental perspectives and research paradigms. Examples from Thailand illustrate the philosophical roots and practical implications of an indigenous Eastern perspective for local business interactions. We explore the privilege afforded in Western, Cartesian paradigms in (Asian) management research and stimulate debate on the benefits of promoting alternative Asian indigenous perspectives for both management research and management practice. We support the idea that Asian management discourse needs more self-confidence and deserves a more prominent place in international research, not least because international management research will greatly benefit from freshly \u27blended\u27 perspectives that incorporate Eastern and Western perspectives

    Point-of-care oral cytology tool for the screening and assessment of potentially malignant oral lesions

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    BACKGROUND: Effective detection and monitoring of potentially malignant oral lesions (PMOL) are critical to identifying early stage cancer and improving outcomes. In this study, the authors describe cytopathology tools including machine learning algorithms, clinical algorithms, and test reports developed to assist pathologists and clinicians with PMOL evaluation. METHODS: Data were acquired from a multi-site clinical validation study of 999 subjects with PMOLs and oral squamous cell carcinoma (OSCC) using a cytology-on-a-chip approach. A machine learning model was trained to recognize and quantify the distributions of four cell phenotypes. A least absolute shrinkage and selection operator (lasso) logistic regression model was trained to distinguish PMOLs and cancer across a spectrum of histopathologic diagnoses ranging from benign, to increasing grades of oral epithelial dysplasia (OED), to OSCC using demographics, lesion characteristics, and cell phenotypes. Cytopathology software was developed to assist pathologists in reviewing brush cytology test results, including high-content cell analyses, data visualization tools, and results reporting. RESULTS: Cell phenotypes were accurately determined through an automated cytological assay and machine learning approach (99.3% accuracy). Significant differences in cell phenotype distributions across diagnostic categories were found in three phenotypes (Type 1 ‘mature squamous’, Type 2 ‘small round’, and Type 3 ‘leukocytes’). The clinical algorithms resulted in acceptable performance characteristics (AUC = 0.81 for benign vs. mild dysplasia and 0.95 for benign vs. malignancy). Conclusion: These new cytopathology tools represent a practical solution for rapid PMOL assessment with the potential to facilitate screening and longitudinal monitoring in primary, secondary, and tertiary clinical care settings
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