17 research outputs found

    Exports and Productivity: Comparable Evidence for 14 Countries

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    We use comparable micro level panel data for 14 countries and a set of identically specified empirical models to investigate the relationship between exports and productivity. Our overall results are in line with the big picture that is by now familiar from the literature: Exporters are more productive than non-exporters when observed and unobserved heterogeneity are controlled for, and these exporter productivity premia tend to increase with the share of exports in total sales; there is strong evidence in favour of self-selection of more productive firms into export markets, but nearly no evidence in favour of the learning-by-exporting hypothesis. We document that the exporter premia differ considerably across countries in identically specified empirical models. In a meta-analysis of our results we find that countries that are more open and have more effective government report higher productivity premia. However, the level of development per se does not appear to be an explanation for the observed cross-country differences.exports; productivity; micro data; international comparison

    Plant chemicals and the sexual behavior of male tephritid fruit flies

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    Plant compounds affect insects in many different ways. In addition to being a food source, plants also contain secondary metabolites that may have positive and negative impacts on insects. The influence of these compounds on sexual behavior, in particular, has been the focus of many recent studies. Here, we review the existing literature on the effects of plant compounds on the sexual behavior of tephritid fruit fly males. We put special focus on polyphagous species whose males congregate in leks, where females exert strong mate selection. We first summarize the main findings related to plant compounds that increase male signaling behavior and attraction of females and consequently increase mating frequency, a phenomenon that has been recorded mainly for species of Anastrepha and Ceratitis. In other tephritid species, males are attracted to phenylpropanoids produced by plants (such as methyl eugenol or raspberry ketone) that, upon encounter, are consumed and sequestered by males. These compounds, or metabolic derivatives, which normally have negligible nutritional value, are included in the pheromone and also confer advantages in a sexual context: enhanced female attraction and improved male mating success. These phenomena have been reported for several Bactrocera species as well as for Zeugodacus cucurbitae. Because many tephritid species are serious pests, the effect of plant compounds on male behavior has been explored for potential incorporation into control strategies such as the sterile insect technique (SIT). We conclude noting several factors, such as age and nutrition during larval and adult stage, that modulate the effect of plant compounds on male mating behavior as well as some prominent gaps that preclude a thorough understanding of the plant-mediated enhancement of male sexual performance and hence limit our ability to effectively utilize phytochemicals in pest control strategies.Instituto de GenéticaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Belliard, Silvina A. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vera, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Bachmann, Guillermo Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética. Laboratorio de Genética de Insectos de Importancia Económica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ruiz, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; ArgentinaFil: Jofre-Barud, Flavia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández, Patricia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Delta del Paraná; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lopez, M. Liza. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Shelly, Todd E. United States Department of Agriculture. Animal and Plant Health Inspection Service; Estados Unido

    Radiaciones ionizantes y su impacto Primer Simposio Internacional sobre Medioambiente (ISE 2017)

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    Son ya varias las décadas en las que en América Latina se ha trabajado arduamente sobre las radiaciones ionizantes; tanto en las ionizantes directas, tales como las partículas beta positivas y negativas, las partículas alfa, los protones, los mesones cargados, los muones y los iones pesados, así como también en las ionizantes indirectas (las producidas por partículas sin cargas), como las generadas por fotones con energías superiores a los 10 keV y los neutrones. Por otro lado, las radiaciones no ionizantes también han sido objeto de detallados estudios, y muy especialmente las provenientes del Sol, como el factor natural más influyente sobre la Tierra. En esta obra se presentan algunos de los avances en los que han participado reconocidos científicos latinoamericanos, como el Dr. Héctor Vega Carrillo, Dr. Daniel Palacios, Dra. Patrizia Pereyra, Dra. Sheila Serrano, y el Dr. Manuel Ernesto Delgado, entre otros. Esta obra puede ser de interés para profesionales del área de la protección radiológica, la ingeniería ambiental, física de la atmósfera y áreas afines, así como para estudiantes

    VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad

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    Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas. En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región. Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades. En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates. El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Effect of isomers and enantiomers of pinene on Ceratitis capitata males mating performance

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    In the world of organic chemistry, isomerism and enantiomerism are chemical properties of organic molecules that defines different biological activities. Particularly, α-copaene shows different attractant activity according to its (+) and (?) configuration on Ceratitis capitata males. It is widely recognized that plant phytochemicals affect the sexual behaviour of Tephritidae fruit fly males. Males of C. capitata increases its mating success after exposure to the volatiles of different essential oils or some pure monoterpenes. However, the role of isomerism and enantiomerism on the reproductive behaviour of fruit flies had not been studied so far. The objective of this study was to evaluate the effect of exposure to isomers and enantiomers of pinene (2,6,6-trimethylbicyclo [3.1.1] hept-2-ene) on the mating success of C. capitata males. Males from a laboratory colony were exposed to α- or β-pinene enantiomers and its sexual performance was evaluated in a mating arena. Experiments consisted in different combinations of two competing males considering the four compounds available according to isomerism and enantiomerism: α (+); α (-); β (+), β (-), and non-exposed males. Then, 8 treatments were performed, males exposed to α/β (+) / (-) vs non-exposed males (4 possible treatments); males exposed to the same isomer but different enantiomer (2 treatments) and males exposed to the same enantiomer but different isomer (2 treatments). The number of mating pairs obtained by each type of male (mating success), the latency to mate and the duration of the copula were recorded for each treatment. The effect of volatiles exposure on male mating success was evaluated by means of a G test of goodness of fit to an equal proportion hypothesis whereas latency to mate and copula duration were compared by means of a Wilcoxon test. Results showed that males exposed to (-) α-pinene achieved more matings than non-exposed males. However, when confronted to (+) α-pinene exposed males they achieved less matings. Latency to mate was shorter for (-) β-pinene exposed males than (+) β-pinene when competing together. Males exposed to (-) α-pinene showed the same tendency when competed with non-exposed males. No statistical differences were found for copula duration. Our results show that isomerism and enantiomerism affects the mating performance of C. capitata males exposed to pinenes.Fil: López, María Liza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Mendoza-san Juan. Estacion Experimental Agropecuaria San Juan. Agencia de Extension Rural Calingasta.; ArgentinaFil: Ruiz, Josefina M.. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jofré Barud, Flavia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Mendoza-san Juan. Estacion Experimental Agropecuaria San Juan. Agencia de Extension Rural Calingasta.; ArgentinaFil: Gomez, María Pía. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Mendoza-san Juan. Estacion Experimental Agropecuaria San Juan. Agencia de Extension Rural Calingasta.; ArgentinaFil: Goane, Lucía. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Valladares, Gabriela. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Juárez, Laura M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Segura, Diego Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo | Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular. Grupo Vinculado Instituto de Genética "Ewald A. Favret" al Iabimo; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Vera, Teresa M.. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán; ArgentinaCongreso Americano de Moscas de la Fruta y X Reunión del Grupo de trabajo de Investigadores en Moscas de la Fruta del Hemisferio OccidentalBogotáColombiaInstituto Colombiano Agropecuari
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