271 research outputs found

    Human capital and university-industry linkages'role in fostering firm innovation : an empirical study of Chile and Colombia

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    A firm's absorptive capacity, human capital and linkages with knowledge institutions have been shown to increase the firm's probability of innovating in OECD economies. Despite its importance for national- and firm-level competitiveness, few papers examine the impact of the same variables for firms innovation in Latin America. This paper investigates the link between firm innovation and its absorption capacity as proxied by the presence of a R&D department, the firm's human capital, and its interaction with research centers and universities. We analyze the case of Chilean and Colombian manufacturing firms using data from innovation surveys. A probit regression model is applied to identify the determinants of innovation activity. We find that collaboration with university and research institutions is associated with an increase in the probability of introducing a new product in Chilean and Colombian firms of 29 and 44 percent, respectively, and it can increase up to 58 percent in the case of Colombian firms interacting with research centers. Moreover, firms whose employees have a higher level of education, or whose managers/supervisors have a higher (perceived) level of knowledge, are more likely to innovate. Although the estimates could be affected by biases and suffer from shortcomings in data, the findings suggest that policies and incentives to increase firm-level human capital and industry-university linkages are important to increase innovation in Latin America.E-Business,Education for Development (superceded),Innovation,Agricultural Knowledge&Information Systems,Labor Policies

    Debris flow mitigation works, Foothills Bypass, Tuen Mun

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    Resistance to echinocandin antifungal agents in the United Kingdom in clinical isolates of Candida glabrata: Fifteen years of interpretation and assessment

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    Candidaemia is widely reported as the fourth most common form of bloodstream infection worldwide. Reports of breakthrough cases of candidaemia are increasing, especially in the context of a move away from azole antifungals as prophylactic or first line treatment towards the use of echinocandin agents. The global evaluation of echinocandin antifungal susceptibility since 2003 has included switches in testing methodologies and the move to a sentinel echinocandin approach for classification reporting. This study compiles previously unpublished data from echinocandin susceptibility testing of UK clinical isolates of C. glabrata received at the Public Health England Mycology Reference Laboratory from 2003 to 2016, and re-evaluates the prevalence of resistance in light of currently accepted testing protocols. From 2015 onwards, FKS gene mutation detection using a novel PyrosequencingÂź assay was assessed as a predictor of echinocandin resistance alongside conventional susceptibility testing. Overall, our data show that echinocandin resistance in UK isolates of C. glabrata is a rare phenomenon and prevalence has not appreciably increased in the last 14 years. The pyrosequencing assay was able to successfully detect hot spot mutations in FKS1 and FKS2, although not all isolates that exhibited phenotypic resistance demonstrated detectable hot spot mutations. We propose that a rapid genomic based detection method for FKS mutations, as part of a multifactorial approach to susceptibility testing, could help provide accurate and timely management decisions especially in regions where echinocandin resistance has been reported to be emerging in this important pathogen

    Investigations into the potential effects of pedoturbation on luminescence dating

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    Much effort has been focussed on understanding the luminescence properties of natural minerals to achieve a reliable, accurate and precise dating technique. However, some field related aspects, such as the influence or effect of post-depositional disturbance on luminescence dates, are as yet underexplored. In the case of pedoturbation, depending on its intensity, the rate of sedimentation and unit thicknesses, potentially the whole sedimentary record at a site can be affected. This may lead to distorted OSL chronologies and erroneous sediment burial ages. Pedoturbation can result in sediment mixing and/or exhumation that affect luminescence both at the bulk and single grain level. Effects of these two principle processes on luminescence ages are examined using standard multigrain and single grain protocols. High resolution sampling of surface gopher mounds was used to determine the efficiency of bio-exhumation in resetting luminescence signal. Results show this is an inefficient mechanism for onsite sediment bleaching. The effects on luminescence signal of bio-mixing were explored by comparing a sample collected from within a krotovina (infilled burrow) to an adjacent undisturbed sample. Results show the difficulties in identifying pedoturbated samples at the single aliquot level and the possible inaccuracies in using the lowest palaeodose values to calculate OSL ages. Where pedoturbation of samples is suspected, use of probability plots of palaeodoses data is recommended. From these plots it is proposed that only data falling within a normal distribution centred on the peak probability be used to calculated OSL ages and to mitigate problems arising from pedoturbation

    Differential Dynamics of Activity Changes in Dorsolateral and Dorsomedial Striatal Loops during Learning

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    The basal ganglia are implicated in a remarkable range of functions influencing emotion and cognition as well as motor behavior. Current models of basal ganglia function hypothesize that parallel limbic, associative, and motor cortico-basal ganglia loops contribute to this diverse set of functions, but little is yet known about how these loops operate and how their activities evolve during learning. To address these issues, we recorded simultaneously in sensorimotor and associative regions of the striatum as rats learned different versions of a conditional T-maze task. We found highly contrasting patterns of activity in these regions during task performance and found that these different patterns of structured activity developed concurrently, but with sharply different dynamics. Based on the region-specific dynamics of these patterns across learning, we suggest a working model whereby dorsomedial associative loops can modulate the access of dorsolateral sensorimotor loops to the control of action.National Institutes of Health (U.S.) (MH60379)United States. Office of Naval Research (N000140410208)Stanley H. and Sheila G. Sydney FundEuropean Union (Grant 201716)McGovern Institute for Brain Research at MIT (Fellowship

    A coupled terrestrial and aquatic biogeophysical model of the Upper Merrimack River watershed, New Hampshire, to inform ecosystem services evaluation and management under climate and land-cover change

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    Accurate quantification of ecosystem services (ES) at regional scales is increasingly important for making informed decisions in the face of environmental change. We linked terrestrial and aquatic ecosystem process models to simulate the spatial and temporal distribution of hydrological and water quality characteristics related to ecosystem services. The linked model integrates two existing models (a forest ecosystem model and a river network model) to establish consistent responses to changing drivers across climate, terrestrial, and aquatic domains. The linked model is spatially distributed, accounts for terrestrial–aquatic and upstream–downstream linkages, and operates on a daily time-step, all characteristics needed to understand regional responses. The model was applied to the diverse landscapes of the Upper Merrimack River watershed, New Hampshire, USA. Potential changes in future environmental functions were evaluated using statistically downscaled global climate model simulations (both a high and low emission scenario) coupled with scenarios of changing land cover (centralized vs. dispersed land development) for the time period of 1980–2099. Projections of climate, land cover, and water quality were translated into a suite of environmental indicators that represent conditions relevant to important ecosystem services and were designed to be readily understood by the public. Model projections show that climate will have a greater influence on future aquatic ecosystem services (flooding, drinking water, fish habitat, and nitrogen export) than plausible changes in land cover. Minimal changes in aquatic environmental indicators are predicted through 2050, after which the high emissions scenarios show intensifying impacts. The spatially distributed modeling approach indicates that heavily populated portions of the watershed will show the strongest responses. Management of land cover could attenuate some of the changes associated with climate change and should be considered in future planning for the region

    Quantifying sample completeness and comparing diversities among assemblages.

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    We develop a novel class of measures to quantify sample completeness of a biological survey. The class of measures is parameterized by an order q ≄ 0 to control for sensitivity to species relative abundances. When q = 0, species abundances are disregarded and our measure reduces to the conventional measure of completeness, that is, the ratio of the observed species richness to the true richness (observed plus undetected). When q = 1, our measure reduces to the sample coverage (the proportion of the total number of individuals in the entire assemblage that belongs to detected species), a concept developed by Alan Turing in his cryptographic analysis. The sample completeness of a general order q ≄ 0 extends Turing's sample coverage and quantifies the proportion of the assemblage's individuals belonging to detected species, with each individual being proportionally weighted by the (q − 1)th power of its abundance. We propose the use of a continuous profile depicting our proposed measures with respect to q ≄ 0 to characterize the sample completeness of a survey. An analytic estimator of the diversity profile and its sampling uncertainty based on a bootstrap method are derived and tested by simulations. To compare diversity across multiple assemblages, we propose an integrated approach based on the framework of Hill numbers to assess (a) the sample completeness profile, (b) asymptotic diversity estimates to infer true diversities of entire assemblages, (c) non‐asymptotic standardization via rarefaction and extrapolation, and (d) an evenness profile. Our framework can be extended to incidence data. Empirical data sets from several research fields are used for illustration.publishedVersionPaid Open Acces

    Flaring Behavior of the Quasar 3C~454.3 across the Electromagnetic Spectrum

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    We analyze the behavior of the parsec-scale jet of the quasar 3C~454.3 during pronounced flaring activity in 2005-2008. Three major disturbances propagated down the jet along different trajectories with Lorentz factors Γ>\Gamma>10. The disturbances show a clear connection with millimeter-wave outbursts, in 2005 May/June, 2007 July, and 2007 December. High-amplitude optical events in the RR-band light curve precede peaks of the millimeter-wave outbursts by 15-50 days. Each optical outburst is accompanied by an increase in X-ray activity. We associate the optical outbursts with propagation of the superluminal knots and derive the location of sites of energy dissipation in the form of radiation. The most prominent and long-lasting of these, in 2005 May, occurred closer to the black hole, while the outbursts with a shorter duration in 2005 Autumn and in 2007 might be connected with the passage of a disturbance through the millimeter-wave core of the jet. The optical outbursts, which coincide with the passage of superluminal radio knots through the core, are accompanied by systematic rotation of the position angle of optical linear polarization. Such rotation appears to be a common feature during the early stages of flares in blazars. We find correlations between optical variations and those at X-ray and γ\gamma-ray energies. We conclude that the emergence of a superluminal knot from the core yields a series of optical and high-energy outbursts, and that the mm-wave core lies at the end of the jet's acceleration and collimation zone.Comment: 57 pages, 23 figures, 8 tables (submitted to ApJ

    Deliberative multiattribute valuation of ecosystem services across a range of regional land-use, socioeconomic, and climate scenarios for the upper Merrimack River watershed, New Hampshire, USA

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    We evaluate the relative desirability of alternative futures for the upper Merrimack River watershed in New Hampshire, USA based on the value of ecosystem services at the end of the 21st century as gauged by its present-day inhabitants. This evaluation is accomplished by integrating land-use and socioeconomic scenarios, downscaled climate projections, biogeophysical simulation models, and the results of a citizen-stakeholder deliberative multicriteria evaluation. We find that although there are some trade-offs between alternative plausible futures, for the most part, it can be expected that future inhabitants of the watershed will be most satisfied if land-use planning in the intervening years prioritizes water supply and flood protection as well as maintenance of existing farmland and forest cover. With respect to climate change, it is expected that future watershed inhabitants will be more negatively affected by the projected loss of snow cover than the anticipated increase in hot summer days. More important than the specific results for the upper Merrimack River watershed, this integrative assessment demonstrates the complex yet ultimately informative potential to link stakeholder engagement with scenario generation, ecosystem models, and multiattribute evaluation for informing regional-scale planning and decision making
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