213 research outputs found
Psychophysiological correlates of peritraumatic dissociative responses in survivors of life-threatening cardiac events
The psychophysiological startle response pattern associated with peritraumatic dissociation (DISS) was studied in 103 survivors of a life-threatening cardiac event (mean age 61.0 years, SD 13.95). Mean time period since the cardiac event was 37 (79 IQD) months. All patients underwent a psychodiagnostic evaluation (including the Peritraumatic Dissociative Experiences Questionnaire) and a psychophysiological startle experience which comprised the delivery of 15 acoustic startle trials. Magnitude and habituation to trials were measured by means of electromyogram (EMG) and skin conductance responses (SCR). Thirty-two (31%) subjects were indexed as patients with a clinically significant level of DISS symptoms. High-level DISS was associated with a higher magnitude of SCR (ANOVA for repeated measures p = 0.017) and EMG (p = 0.055) and an impaired habituation (SCR slope p = 0.064; EMG slope p = 0.005) in comparison to subjects with no or low DISS. In a subgroup analysis, high-level DISS patients with severe post-traumatic stress disorder (PTSD; n = 11) in comparison to high-level DISS patients without subsequent PTSD (n = 19) exhibited higher EMG amplitudes during all trials (repeated measures analysis of variance IF = 5.511, p = 0.026). The results demonstrate exaggerated startle responses in SCR and EMG measures - an abnormal defensive response to high-intensity stimuli which indicates a steady state of increased arousal. DISS patients without PTSD exhibited balanced autonomic responses to the startle trials. DISS may, therefore, unfold malignant properties only in combination with persistent physiological hyperarousability. Copyright (C) 2002 S. Karger AG, Basel
Captura de carbono en ra?ces finas y estructurales en bosques alto-andinos y sistemas agroforestales en asocio con ?rboles dispersos y cultivos en Santa Isabel, Tolima
75 p. Recurso Electr?nicoLas ra?ces finas (di?metro < 2 mm) se han caracterizado por ser un componente radicular importante dentro de la absorci?n de nutrientes y din?mica del carbono. Se evalu? la captura de carbono en ra?ces finas mediante un dise?o completamente al azar con tres tratamientos (bosques, cultivos y pasturas); del mismo modo se utiliz? un dise?o con arreglo en franjas (profundidad: 0-10, 10-20, 20-30, 30-40, 40-50 cm) y cinco repeticiones. Se colectaron bloques de 10 x 10 x 10 cm que fueron lavados y tamizados para separar las ra?ces finas y secadas hasta peso constante. La biomasa de ra?ces estructurales se estim? con la ecuaci?n desarrollada por Cairns et al. (1997). Se encontraron diferencias estad?sticas (p<0,05) en la acumulaci?n de carbono entre sistemas: mayor en bosques que en pasturas y cultivos (ra?ces finas: 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha, y estructurales: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectivamente). La profundidad tiene un efecto significativo (p<0,05) en la acumulaci?n de carbono en ra?ces finas, siendo mayor en las primeras capas y reduci?ndose en las profundas: 55% del carbono se encuentra en los primeros 20 cm del suelo y 12% entre 40-50 cm. Los agentes fisicoqu?micos que caracterizan la cobertura del suelo determinan el crecimiento y desarrollo de las ra?ces. La conservaci?n de bosques nativos implica la retenci?n de cantidades importantes de carbono que al reportar un cambio de uso del suelo podr?a generar un incremento en las concentraciones de CO2 a la atm?sfera.
Palabras claves: Almacenamiento de carbono, Biodiversidad, Biomasa, Servicios ambientales.Fine roots (diameter < 2 mm) has been characterized as a mean root component in nutrient absorption and carbon dynamics. Carbon sequestration was evaluated inside fine roots through a completely random design with three treatments such as forests; crops and pastures. Similarly, It was applied a design with pursuant slots (depth: 0-10; 10-20; 20-30; 30-40; 40-50 cm) and five repetitions. Blocks were collected of 10 x 10 x 10 cm in dimension which were washed and sifted in order to separate the fine roots and dried them until constant weight. Structural root?s Biomass was estimated with the equation developed by Cairns et al. (1997). It was found statistic differences (p<0,05) on the accumulation of carbon between systems: higher in forests than pastures and crops (fine roots : 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha and structural ones: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectively). Depth has a significant effect (p<0,05) on the increasing of carbon at fine roots being higher on the first layers and decreasing at the last ones: 55% of carbon is found in the first 20 cm of the soil and 12% between 40-50 cm. Physicochemical agents that characterize the soil coverage determine the growth and development of roots. Consequently, native forests preservation implies retention of important amounts of carbon since it shows a change on the use of soil could produce an increase on the concentrations of CO2 at the atmosphere.
Keywords: Carbon storage, Biodiversity, Biomass, Environmental service
Captura de carbono en ra?ces finas y estructurales en bosques alto-andinos y sistemas agroforestales en asocio con ?rboles dispersos y cultivos en Santa Isabel, Tolima
75 p. Recurso Electr?nicoLas ra?ces finas (di?metro < 2 mm) se han caracterizado por ser un componente radicular importante dentro de la absorci?n de nutrientes y din?mica del carbono. Se evalu? la captura de carbono en ra?ces finas mediante un dise?o completamente al azar con tres tratamientos (bosques, cultivos y pasturas); del mismo modo se utiliz? un dise?o con arreglo en franjas (profundidad: 0-10, 10-20, 20-30, 30-40, 40-50 cm) y cinco repeticiones. Se colectaron bloques de 10 x 10 x 10 cm que fueron lavados y tamizados para separar las ra?ces finas y secadas hasta peso constante. La biomasa de ra?ces estructurales se estim? con la ecuaci?n desarrollada por Cairns et al. (1997). Se encontraron diferencias estad?sticas (p<0,05) en la acumulaci?n de carbono entre sistemas: mayor en bosques que en pasturas y cultivos (ra?ces finas: 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha, y estructurales: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectivamente). La profundidad tiene un efecto significativo (p<0,05) en la acumulaci?n de carbono en ra?ces finas, siendo mayor en las primeras capas y reduci?ndose en las profundas: 55% del carbono se encuentra en los primeros 20 cm del suelo y 12% entre 40-50 cm. Los agentes fisicoqu?micos que caracterizan la cobertura del suelo determinan el crecimiento y desarrollo de las ra?ces. La conservaci?n de bosques nativos implica la retenci?n de cantidades importantes de carbono que al reportar un cambio de uso del suelo podr?a generar un incremento en las concentraciones de CO2 a la atm?sfera.
Palabras claves: Almacenamiento de carbono, Biodiversidad, Biomasa, Servicios ambientalesFine roots (diameter < 2 mm) has been characterized as a mean root component in nutrient absorption and carbon dynamics. Carbon sequestration was evaluated inside fine roots through a completely random design with three treatments such as forests; crops and pastures. Similarly, It was applied a design with pursuant slots (depth: 0-10; 10-20; 20-30; 30-40; 40-50 cm) and five repetitions. Blocks were collected of 10 x 10 x 10 cm in dimension which were washed and sifted in order to separate the fine roots and dried them until constant weight. Structural root?s Biomass was estimated with the equation developed by Cairns et al. (1997). It was found statistic differences (p<0,05) on the accumulation of carbon between systems: higher in forests than pastures and crops (fine roots : 4,2 ? 0,6 vs 2,1 ? 0,4 vs 0,6 ? 0,25 t/ha and structural ones: 26 ? 2,8 vs 10 ? 0,9 t/ha, respectively). Depth has a significant effect (p<0,05) on the increasing of carbon at fine roots being higher on the first layers and decreasing at the last ones: 55% of carbon is found in the first 20 cm of the soil and 12% between 40-50 cm. Physicochemical agents that characterize the soil coverage determine the growth and development of roots. Consequently, native forests preservation implies retention of important amounts of carbon since it shows a change on the use of soil could produce an increase on the concentrations of CO2 at the atmosphere.
Keywords: Carbon storage, Biodiversity, Biomass, Environmental service
Caracterización Molecular de la Diversidad Fúngica de los Bosques Llucud y Palictahua: Potencialidades en Control Biológico/Molecular Characterization of Diversity Fungic of the Llucud and Palictahua Forests: Potential in Biological Control
Dentro de los microorganismos más abundantes que se pueden encontrar en formaciones ecosistémicas naturales como los bosques andinos del Ecuador se encuentran los hongos microscópicos, los cuales desempeñan funciones cruciales en dichos ecosistemas. Por lo cual el objetivo de esta investigación fue caracterizar molecularmente la diversidad de hongos presentes en los bosques nativos Llucud y Palictahua, estableciendo sus potencialidades de uso en el control biológico de plagas y enfermedades que afectan a los cultivos agrícolas y cuyo control en su mayoría se lo realiza con plaguicidas químicos. Mediante secuenciación de próxima generación (NGS por sus siglas en inglés) de las muestras compuestas de suelo tomadas del horizonte “A” (rizósfera) de cada bosque, se identificaron 56 especies de hongos en Palictahua y 38 en Llucud, presentándose en ambos bosques un total de 6 hongos con importantes potencialidades para su uso en el control biológico, dentro de las cuales se encontraron: Brachyphoris oviparasitica (nematófago), Simplicillium (entomopatógeno y micoparásito), Hamamotoa lignophila (levadura con actividad Killer) en Llucud, y Metarhizium robertsii (entomopatógeno), Brachyphoris oviparasitica (nematófago) y Paraphaeosphaeria parmeliae (micoparásito) en Palictahua. El Bosque Palictahua presentó mayor diversidad de hongos que el bosque Llucud, sin embargo es importante cuidar ambos bosques, pues poseen una gran riqueza microbiana con un sinnúmero de posibilidades de uso en la medicina, industria, biotecnología y otros campos.
Among the most abundant microorganisms that can be found in natural ecosystem formations such as the Andean forests of Ecuador are microscopic fungi, which play crucial roles in these ecosystems. So that the objective of this research was to molecularly characterize the diversity of fungi present in the native forests Llucud and Palictahua, establishing their potential for use in the biological control of pests and diseases that affect agricultural crops and whose control is mostly carried out with chemical pesticides. Through next-generation sequencing (NGS for its acronym in English) of compound samples of soil took from “A” horizon (rhizosphere). 56 species of fungi were identified in Palictahua and 38 in Llucud, presenting in both forests a total of 6 fungi with significant potential for use in biological control, among which were found: Brachyphoris oviparasitica (nematophagous), Simplicillium sp. (entomopathogen and mycoparasite), Hamamotoa lignophila (yeast with Killer activity) in Llucud, and Metarhizium robertsii (entomopathogen), Brachyphoris oviparasitica (nematophagous) and Paraphaeosphaeria parmeliae (mycoparasite) in Palictahua. The Palictahua forest presented greater diversity of fungi than the Llucud forest, however it is important to take care of both forests, since they have a great microbial richness with a myriad of possibilities of use in medicine, industry, biotechnology and other fields.
Palabras clave: Biodiversidad, Microbiota, Plaguicidas.
Keywords: Biodiversity, Microbiota, Pesticides
Closing the cycle for the cut rose industry by the reuse of its organic wastes: A case study in Ecuador
The soil conditions and the yield and quality of Rosa sp. var. Freedom were determined following the
incorporation into the soil of rose waste composts, with or without fertigation; the effects of these
treatments were compared with those of non-stabilised chopped rose wastes þ fertigation (FWF). The
growing conditions were those of a commercial greenhouse. The use of the composts, alone or combined
with fertigation, increased the available P and K contents of the soil with respect to FWF. However, only
the compost þ fertigation treatments improved, in general, the soil fertility regarding the organic matter
(OM), nitrogen and available micronutrient concentrations, in comparison to FWF. When the composts
were added alone, irrigation with alkaline water increased the soil pH and, in consequence, reduced the
availability of micronutrients. Overall, the combined use of compost and fertigation increased the cut
rose yield and quality relative to the application of compost alone and FWF. Principal component analysis
indicated that the OM, available Cu, Mn and Zn and total N contents and the pH of the soil were the
principal soil parameters determining the yield and quality of the roses. This analysis classified the
treatments in three groups: the compost þ fertigation treatments; the treatments with compost alone;
and the FWF treatment. The compost þ fertigation treatments gave the highest net income (average for
these treatments ¼ 80388.92 US dollars ha 1). Therefore, the compost þ fertigation treatments were
highly beneficial with regard to increasing soil fertility and cut rose yield, quality and profitability
Pathogenicity of Entomopathogenic Fungi on the Weevil of the Andes (Premnotrypes vorax Hustache) of the Potato (Solanum tuberosum L.) in Chimborazo Province, Ecuador
From thirty native isolates of entomopathogenic fungi, which were obtained from corpses of larvae and adults of Andean weevil (Premnotrypes vorax Hustache); two fungi with entomopathogenic characteristics were selected through laboratory tests, which will be used in a program of integrated management of this pest in the Ecuadorian inter-Andean region. The pathogenicity of the 30 isolates was determined by the mortality that they caused in larvae and adults and it was expressed in percentage; for this, a complete randomized design (CRD) was used. The LC50 and TL50 were determined by Probit analysis. The two selected isolates corresponded to: Metarhizium anisopliae (Metschnikoff 1879) Sorokin 1883 (A13) and Beauveria bassiana (Bals.-Criv.) Vuill. 1912 (A21), which proved to be the best, because they caused the highest mortality in larvae of the fourth instar and adults of P. vorax. The Probit analysis showed that LC50 for A21 isolate (B. bassiana) in fourth instar larvae was obtained with a concentration of 1,75x109 spores/ml and 1,08x109 spores/ml for adults. Instead for A13 isolate (M. anisopliae), the LC50 was obtained with a concentration of 1,65x109 spores/ml for larvae and 2,42x109 spores/ml for adults. The LT50 for the selected isolates at the indicated concentrations, was 4,84 and 4,32 days for larvae with A13 and A21 isolates respectively, while, for adults, the shortest time was obtained with A21 isolate in 4.36 days, compared with A13 isolate, that delayed 20,70 days. The larval stage of P. vorax was the most susceptible to A13 isolate, on the other hand, larvae and adults were equally susceptible to A21 isolate at the indicated concentrations. According to the results obtained, the two selected isolates can be used as an alternative to the use of conventional agrochemicals, which will contribute to a more ecological production
Secondhand tobacco smoke in bars and restaurants in Santiago, Chile: evaluation of partial smoking ban legislation in public places
To compare air nicotine concentrations according to the smoking policy selected by bars/restaurants in Santiago, Chile before and after the enactment of partial smoking ban legislation in 2007 (establishments could be smoke free, have segregated (mixed) smoking and non-smoking areas, or allow smoking in all areas). The study measured air nicotine concentrations over 7 days to characterise secondhand smoke exposure in 30 bars/restaurants in 2008. Owner/manager interviews and physical inspections were conducted. Median IQR air nicotine concentrations measured in all venues were 4.38 (0.61-13.62) μg/m(3). Air nicotine concentrations were higher in bars (median 7.22, IQR 2.48-15.64 μg/m(3)) compared to restaurants (1.12, 0.15-9.22 μg/m(3)). By smoking status, nicotine concentrations were higher in smoking venues (13.46, 5.31-16.87 μg/m(3)), followed by smoking areas in mixed venues (9.22, 5.09-14.90 μg/m(3)) and non-smoking areas in mixed venues (0.99, 0.19-1.27 μg/m(3)). Air nicotine con
Seismic fragility curves for a concrete bridge using structural health monitoring and digital twins
This paper presents the development of seismic fragility curves for a precast reinforced concrete bridge instrumented with a structural health monitoring (SHM) system. The bridge is located near an active seismic fault in the Dominican Republic (DR) and provides the only access to several local communities in the aftermath of a potential damaging earthquake; moreover, the sample bridge was designed with outdated building codes and uses structural detailing not adequate for structures in seismic regions. The bridge was instrumented with an SHM system to extract information about its state of structural integrity and estimate its seismic performance. The data obtained from the SHM system is integrated with structural models to develop a set of fragility curves to be used as a quantitative measure of the expected damage; the fragility curves provide an estimate of the probability that the structure will exceed different damage limit states as a function of an earthquake intensity measure. To obtain the fragility curves a digital twin of the bridge is developed combining a computational finite element model and the information extracted from the SHM system. The digital twin is used as a response prediction tool that minimizes modeling uncertainty, significantly improving the predicting capability of the model and the accuracy of the fragility curves. The digital twin was used to perform a nonlinear incremental dynamic analysis (IDA) with selected ground motions that are consistent with the seismic fault and site characteristics. The fragility curves show that for the maximum expected acceleration (with a 2% probability of exceedance in 50 years) the structure has a 62% probability of undergoing extensive damage. This is the first study presenting fragility curves for civil infrastructure in the DR and the proposed methodology can be extended to other structures to support disaster mitigation and post-disaster decision-making strategie
Cuantificación de metales en aguas de riego. Estudio de caso en la provincia de Chimborazo.
El crecimiento de la agroindustria en el Ecuador ha causado en los últimos años graves problemas de contaminación ambiental que afectan a sus recursos naturales, por lo cual es importante aplicar estrategias cada vez más eficaces para determinar las fuentes de contaminación y mitigar sus impactos en el ambiente. Una de las más importantes es la presencia de metales pesados, por lo tanto, es fundamental la determinación cuantitativa de ellos para llevar a cabo su gestión adecuada. La provincia de Chimborazo se encuentra ubicada en la zona central de los Andes ecuatorianos y una de sus principales groindustrias es la relacionada con la producción de plantas ornamentales, cuya contaminación por metales pesados no ha sido suficientemente estudiada, especialmente en lo concerniente a las aguas de riego. El objetivo de este trabajo de investigación fue determinar cuantitativamente por espectroscopía de emisión atómica mediante plasma de acoplamiento inductivo, el grado de contaminación por metales pesados de las aguas de riego de la Industria Florícola “White River Roses” del cantón Penipe. Los resultados mostraron que, en general, el agua de riego que se utiliza en esta industria agrícola no contiene cantidades significativas de metales pesados.The growth of agribusiness in Ecuador in recent years has caused serious problems of environmental contamination affecting its natural resources, so it is important to implement effective strategies to determine the sources of pollution and mitigate their impacts on the environment. One of the most important is the presence of heavy metals, therefore, it is essential to determine quantitatively them to carry out their proper management. The province of Chimborazo is located in the central zone of Ecuadorian Andes and one of its main agroindustries is related to the production of ornamental plants, whose contamination by heavy metals has not been sufficiently studied, especially with regard to the irrigation waters. The aim of this research was to determine quantitatively by atomic emission spectroscopy using inductive coupling plasma, the degree of contamination by heavy metals of the irrigation water of the Floriculture Industry White River Roses of the Penipe Canton. The results showed that, in general, the irrigation water used in this agricultural industry does not contain significant amounts of heavy metals
IMECE2008-66225 ATOMIZATION CHARACTERISTICS, GLOBAL EMISSIONS, AND TEMPERATURE IN BIOFUEL AND PETROLEUM FUEL SPRAY FLAMES
ABSTRACT Spray flame characteristics of canola methyl ester biofuel (CME) and petroleum fuel (No. 2D) are described. An enclosed spray flame in a heated co-flow air environment at ambient pressure was studied. A single nozzle, swirl-type, air-blast atomizer with a nozzle diameter of 300 microns was used to create the spray. The spray droplet size and velocity distributions were measured using a two-component phase Doppler particle analyzer. In-flame temperature profiles were measured using a type-R thermocouple. Global emission indices of NO and CO were derived from concentration measurements in the combustion products. The overall equivalence ratio was kept at 0.75 to simulate lean burning conditions. The changes in atomization air flow rate produced similar changes in atomization characteristics of both fuels. Emission indices of NO and CO for petroleum fuel were higher than those of the CME fuel. In-flame temperature levels were lower for the CME fuel than for the petroleum fuel at corresponding flame locations. NOMENCLATURE CME-Canola methyl ester D 32 -Sauter mean diameter NDIR-Nondispersive infrared PDPA-Phase Doppler particle analyzer T cf = Air co-flow temperature V f = Volumetric flow rate of fuel V aa = Volumetric flow rate of atomization air V cf = Volumetric flow rate of air co-flo
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