297 research outputs found

    Bases para una teoría general del desarrollo económico

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    Bibliografía selecta sobre desarrollo económico con especial referencia a América Latina

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    Used-habitat calibration plots: a new procedure for validating species distribution, resource selection, and step-selection models

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    “Species distribution modeling” was recently ranked as one of the top five “research fronts” in ecology and the environmental sciences by ISI's Essential Science Indicators (Renner and Warton 2013), reflecting the importance of predicting how species distributions will respond to anthropogenic change. Unfortunately, species distribution models (SDMs) often perform poorly when applied to novel environments. Compounding on this problem is the shortage of methods for evaluating SDMs (hence, we may be getting our predictions wrong and not even know it). Traditional methods for validating SDMs quantify a model's ability to classify locations as used or unused. Instead, we propose to focus on how well SDMs can predict the characteristics of used locations. This subtle shift in viewpoint leads to a more natural and informative evaluation and validation of models across the entire spectrum of SDMs. Through a series of examples, we show how simple graphical methods can help with three fundamental challenges of habitat modeling: identifying missing covariates, non-linearity, and multicollinearity. Identifying habitat characteristics that are not well-predicted by the model can provide insights into variables affecting the distribution of species, suggest appropriate model modifications, and ultimately improve the reliability and generality of conservation and management recommendations

    Association of asthma symptoms with peak particulate air pollution and effect modification by anti-inflammatory medication use.

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    Maxima of hourly data from outdoor monitors may capture adverse effects of outdoor particulate matter (PM) exposures in asthmatic children better than do 24-hr PM averages, which form the basis of current regulations in the United States. Also, asthmatic children on anti-inflammatory medications may be protected against the proinflammatory effects of air pollutants and aeroallergens. We examined strengths of pollutant associations with asthma symptoms between subgroups of asthmatic children who were on versus not on regularly scheduled anti-inflammatory medications, and tested associations for different particle averaging times. This is a daily panel study of 22 asthmatic children (9-19 years of age) followed March through April 1996 (1,248 person-days). They lived in nonsmoking households in a semirural area of Southern California within the air inversion mixing zone (range, 1,200-2,100 feet) with transported air pollution from urban areas of Southern California. The dependent variable derived from diary ordinal scores is episodes of asthma symptoms that interfered with daily activities. Minimum to 90th-percentile levels of exposures at the outdoor monitoring site were 12-63 microg/m(3) for 1-hr PM < 10 microm in aerodynamic diameter (PM(10)); 8-46 microg/m(3) for 8-hr PM(10); 7-32 microg/m(3) for 24-hr PM(10); 45-88 ppb for 1-hr O(3); 6-26 ppb for 8-hr NO(2); 70-4,714 particles/m(3) for 12-hr daytime fungi; and 12-744 particles/m(3) for 24-hr pollen. Data were analyzed with generalized estimating equations controlling for autocorrelation. There was no confounding by weather, day of week, or linear time trend. Associations were notably stronger in 12 asthmatic children who were not taking anti-inflammatory medications versus 10 subjects who were. Odds ratios (95% confidence intervals) for asthma episodes in relation to lag 0 minimum to 90th-percentile pollutant changes were, respectively, 1-hr maximum PM(10), 1.92 (1.22-3.02) versus 0.96 (0.25-3.69); 8-hr maximum PM(10), 1.68 (0.91-3.09) versus 0.75 (0.18-3.04); 24-hr average PM(10), 1.35 (0.82-2.22) versus 0.80 (0.24-2.69); 1-hr maximum O(3), 1.28 (0.75-2.17) versus 0.76 (0.24-2.44); 8-hr maximum NO(2), 1.91 (1.07-3.39) versus 1.08 (0.30-3.93); 12-hr fungi, 1.89 (1.24-2.89) versus 0.90 (0.35-2.30); 24-hr pollen, 1.90 (0.99-3.67) versus 0.85 (0.18-3.91). Pollutant associations were stronger during respiratory infections in subjects not on anti-inflammatory medications. Although lag 0 1-hr maximum PM(10) showed the strongest association, the most robust associations were for lag 0 and 3-day moving averages (lags 0-2) of 8-hr maximum and 24-hr mean PM(10) in sensitivity analyses testing for thresholds. Most pollutant effects were largely driven by concentrations in the upper quintile. The divergence of exposure-response relationships by anti-inflammatory medication use is consistent with experimental data on inflammatory mechanisms of airborne pollutants and allergens

    Human preparedness: Relational infrastructures and medical countermeasures in Sierra Leone

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    This paper examines health worker experiences in two areas of post-epidemic preparedness in Sierra Leone - vaccine trials and laboratory strengthening - to reflect on the place of people in current models of epidemic response. Drawing on ethnographic research and interviews with health workers in the aftermath of Ebola, it explores the hopes and expectations that interventions foster for frontline workers in under-resourced health systems, and describes the unseen work involved in sustaining robust response infrastructures. Our analysis focuses on what it means for the people who sustain health systems in an emergency to be 'prepared' for an epidemic. Human preparedness entails more than the presence of a labour force; it involves building and maintaining 'relational infrastructures', often fragile social and moral relationships between health workers, publics, governments, and international organisations. The COVID-19 pandemic has underscored the value of rethinking human resources from an anthropological perspective, and investing in the safety and support of people at the forefront of response. In describing the labour, personal losses, and social risks undertaken by frontline workers for protocols and practicality to meet in an emergency context, we describe the social process of preparedness; that is, the contextual engineering and investment that make response systems work

    Notions of agency in early literacy classrooms: assemblages and productive intersections

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    Agency and its role in the early literacy classroom has long been a topic for debate. While sociocultural accounts often portray the child as a cultural agent who negotiates their own participation in classroom culture and literacy learning, more recent framings draw attention from the individual subject, instead seeing agency as dispersed across people and materials. In this article I draw on my experiences of following children as they followed their interests in an early literacy classroom, drawing on the concepts of assemblage and people yet to come, as defined by Deleuze and Guattari and Spinoza’s common notion. I provide one illustrative account of moment-by-moment activity and suggest that in education settings it is useful to see activity as a direct and ongoing interplay of three dimensions: children’s moving bodies; the classroom; and its materials. I propose that children’s ongoing movements create possibilities for ‘doing’ and ‘being’ that flow across and between children. I argue that thinking with assemblage can draw attention to both the potentiality and the power dynamics inherent in the ongoing present and also counter preconceived notions of individual child agency and linear trajectories of literacy development, and the inequalities this these concepts can perpetuate within early education settings

    Ornamental plants: annual reports and research summaries

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    The Ohio State University Extension Nursery, Landscape, and Turf Team (ENLTT) -- Extension Nursery, Landscape, and Turf Team (ENLTT) directory -- An evaluation of composts for landscape soil amendments / Mary Ann Rose and Hao Wang -- Aesthetic evaluation of crabapples at Secrest Arboretum in Wooster, Ohio: 1994-1995 / James A. Chatfield, Erik A. Draper, Kenneth C. Cochran, Peter W. Bristol and Charles E. Tubesing -- Evaluation of crabapples for apple scab at Secrest Arboretum in Wooster, Ohio: 1995 / Erik A. Draper, James A. Chatfield, Kenneth C. Cochran, Peter W. Bristol and Charles E. Tubesing -- Emergence, longevity, and aesthetic evaluations of flowers in ornamental crabapples at Secrest Arboretum in Wooster, Ohio: 1995 / Erik A. Draper, James A. Chatfield and Kenneth C. Cochran -- Environmental and cultural ornamental plant problems in Ohio: 1995 / Pamela J. Bennett and Jane A. Martin -- 1995 -A Challenging Year for Ohio golf courses / Joseph W. Rimelspach, John R. Street, Karl Danneberger, William E. Pound, Barbara Bloetscher -- Plant insect pest problems in Ohio: 1995 / Joseph F. Boggs, David J. Shetlar, Gary Yu Gao, Daniel Balser, Douglas C. Caldwell, Randall H. Zondag and James A. Chatfield -- Gypsy moth in Ohio: 1995 / Allan Baumgard, David F. James and Randall H. Zondag -- Landscape ornamental disease problems in Ohio: 1995 / James A. Chatfield, Nancy Taylor, Randall H. Zondag, Mary Ann Rose, Gary Yu Gao, Daniel R. Balser and David J. Shetlar -- The Response of native and naturalized trees to construction activity / T. Davis Sydnor, Joseph F. Boggs and Mary Ann Ros

    An exploration of parents’ preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment

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    Background: An increased awareness of patients’ and parents’ care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents’ preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA).&lt;p&gt;&lt;/p&gt; Methods: A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents’ monetary valuation of health and service improvements.&lt;p&gt;&lt;/p&gt; Results: Every attribute in the DCE was statistically significant (p &#60; 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents’ preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents’ estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05.&lt;p&gt;&lt;/p&gt; Conclusions: In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents’ preferences.&lt;p&gt;&lt;/p&gt
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