645 research outputs found

    Evaluation of the Evacuation of Essential Buildings: Interaction of Structural and Human Behaviour through Nonlinear Time-History Analysis and Agent-Based Modelling

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    In this article, a performance assessment of the evacuation system is established for educational buildings. Structural and geotechnical information of the building is collected and introduced into a database. A similar procedure was realized for the information related to the occupants. Using this information, a) the structural fragility and localized collapse were determined and b) the interaction of the person with the partial collapse was established. For the first aspect, nonlinear time history was used, and for the second, the agent-based modeling was applied to recreate the reaction of people that face the micro collapse. Therefore, the important results of this evaluation are: 1) To localize collapsed beans and columns that make inoperable evacuation routes, 2) to localize bottleneck areas that people concentration during evacuation, and 3) quantification of affected people, in terms of persons caught up in the building that cannot evacuate

    Classification of coffee beans by GC-C-IRMS, GC-MS, and 1H-NMR

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    In a previous work using 1H-NMR we reported encouraging steps towards the construction of a robust expert system for the discrimination of coffees from Colombia versus nearby countries (Brazil and Peru), to assist the recent protected geographical indication granted to Colombian coffee in 2007.This system relies on fingerprints acquired on a 400MHz magnet and is thus well suited for small scale random screening of samples obtained at resellers or coffee shops. However, this approach cannot easily be implemented at harbour's installations, due to the elevated operational costs of cryogenic magnets. This limitation implies shipping the samples to the NMR laboratory, making the overall approach slower and thereby more expensive and less attractive for large scale screening at harbours. In this work, we report on our attempt to obtain comparable classification results using alternative techniques that have been reported promising as an alternative toNMR: GC-MS andGC-C-IRMS.Although statistically significant information could be obtained by all threemethods, the results showthat the quality of the classifiers dependsmainly on the number of variables included in the analysis; hence NMR provides an advantage since more molecules are detected to obtain a model with better predictions

    Analysis of particulate emissions from tropical biomass burning using a global aerosol model and long-term surface observations

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    We use the GLOMAP global aerosol model evaluated against observations of surface particulate matter (PM₂⋅₅) and aerosol optical depth (AOD) to better understand the impacts of biomass burning on tropical aerosol over the period 2003 to 2011. Previous studies report a large underestimation of AOD over regions impacted by tropical biomass burning, scaling particulate emissions from fire by up to a factor of 6 to enable the models to simulate observed AOD. To explore the uncertainty in emissions we use three satellite-derived fire emission datasets (GFED3, GFAS1 and FINN1). In these datasets the tropics account for 66-84% of global particulate emissions from fire. With all emission datasets GLOMAP underestimates dry season PM₂⋅₅ concentrations in regions of high fire activity in South America and underestimates AOD over South America, Africa and Southeast Asia. When we assume an upper estimate of aerosol hygroscopicity, underestimation of AOD over tropical regions impacted by biomass burning is reduced relative to previous studies. Where coincident observations of surface PM₂⋅₅ and AOD are available we find a greater model underestimation of AOD than PM₂⋅₅, even when we assume an upper estimate of aerosol hygroscopicity. Increasing particulate emissions to improve simulation of AOD can therefore lead to overestimation of surface PM₂⋅₅ concentrations. We find that scaling FINN1 emissions by a factor of 1.5 prevents underestimation of AOD and surface PM₂⋅₅ in most tropical locations except Africa. GFAS1 requires emission scaling factor of 3.4 in most locations with the exception of equatorial Asia where a scaling factor of 1.5 is adequate. Scaling GFED3 emissions by a factor of 1.5 is sufficient in active deforestation regions of South America and equatorial Asia, but a larger scaling factor is required elsewhere. The model with GFED3 emissions poorly simulates observed seasonal variability in surface PM₂⋅₅ and AOD in regions where small fires dominate, providing independent evidence that GFED3 underestimates particulate emissions from small fires. Seasonal variability in both PM₂⋅₅ and AOD is better simulated by the model using FINN1 emissions. Detailed observations of aerosol properties over biomass burning regions are required to better constrain particulate emissions from fires

    Biovalorization of Brewery Waste by Applying Anaerobic Digestion

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    In the food industry, the brewing sector holds a strategic economic position: in the year 2013, the beer production of the EU-28 was equal to 383,553,000 hL. The brewing process includes chemical and biochemical reactions and solid-liquid separations, involving the generation of various residues and by-products, among which the major two fractions are brewer’s spent grain (BSG), and exhausted brewery yeast (BY). Although until today their main use has been for animal feed, in recent years, several studies have investigated the application of anaerobic digestion in order to revalue the brewery wastes. In this work, specific methane production (SMP) and first-order solubilisation (disintegration+ hydrolysis) rates (ksol) for BSG and BY were evaluated. Biomethanation tests were performed in 5-L fed-batch stirred reactors at several substrate/inoculum ratios. The obtained SMP ranged from 0.255 L CH4 g–1 COD for exhausted brewery yeast to 0.284 L CH4 g–1 COD for brewer’s spent grain. The estimated ksol values ranged from 0.224 d–1 for BSG to 0.659 d–1 for BY

    Seed dormancy responses to temperature relate to Nothofagus species distribution and determine temporal patterns of germination across altitudes in Patagonia

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    507-520. Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. . By coupling mathematical models with ecological data we investigated the contribution of seed temperature responses to the dynamics of germination of three Nothofagus species that are sharply distributed across different altitudes in the Patagonian Andes. . Seed responsiveness to temperature of the three Nothofagus species was linked to the thermal characteristics of their preferred ecological niche. In their natural distribution range, there was overlap in the timing of germination of the species, which was restricted to mid - spring. By contrast, outside their species distribution range, germination was temporally uncoupled with altitude. This phenomenon was described mathematically by the interplay between interspecific differences in seed population thermal parameters and the range in soil thermic environments across different altitudes. . The observed interspecific variations in seed responsiveness to temperature and its environmental regulation, constitute a major determinant of the dynamics of Nothofagus germination across elevations. This phenomenon likely contributes to the maintenance of patterns of species abundance across altitude by placing germinated seeds in a favorable environment for plant growth

    Time-related efficacy of liver cell isografts in fulminant hepatic failure

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    We and others have reported that dispersed liver cells transplanted into the spleen parenchyma of syngeneic rats remained functional and viable for a long time. This report describes our results with hepatocellular transplantation as a therapeutic method in a model of fulminant hepatic failure (FHF) in the rat. 60 male Sprague-Dawley rats weighing 200-250 g were used. The FHF was reached through an Eck's fistula with 2/3 hepatectomy at the same time. This model produced lethal hepatic failure in a highly reproducible manner. Liver cells were isolated by the collagenase method. 40 X 10(6) hepatocytes suspended in Hanks' balanced salt solution were transplanted into the spleen parenchyma 24 hr before (group 1), at the same time as (group 2), and 24 hr after (group 3) FHF was achieved. Additional sham-operated animals (groups 4 and 5) and a control group (group 6) were used. The hepatocellular transplantation markedly increased the survival of the animals with induced FHF to 80% (group 1) and 60% (group 2)--but not in group 3 (20%),--compared with 10% in the control group. This study shows that dispersed liver cells transplanted into the spleen can provide sufficient support to allow animals with lethal hepatic failure to survive and recover. Nevertheless the efficacy of transplantation is a time-related phenomenon with the FHF induction

    SEROPREVALENCIA DE Neospora caninum EN PERROS DE ESTABLOS LECHEROS DE LA CUENCA IZQUIERDA DEL VALLE DEL MANTARO

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    La neosporosis es una enfermedad emergente, considerada causa importante de aborto en el ganado bovino y de procesos neuromusculares graves en perros. El objetivo del presente estudio fue determinar la seroprevalencia de Neospora caninum en perros de establos lecheros de la cuenca izquierda del valle del Mantaro. Se evaluaron 124 sueros de perros, provenientes de 24 establos lecheros de las provincias de Huancayo, Jauja y Concepción. Se halló una prevalencia de anticuerpos contra N. caninum de 19.4 ± 7.0% (24/124), en una dilución de 1:50, mediante la prueba de inmunofluorescencia indirecta. El porcentaje de establos que poseían al menos un perro infectado fue de 62.5% (15/24). No se halló asociación entre la tasa de infección y las variables ubicación geográfica (provincia), edad, sexo y procedencia (en el establo o en los alrededores). Estos resultados demuestran que los caninos del valle del Mantaro presentan una prevalencia moderada de infección con N. caninum; y considerando que dicha infección está presente en la mayoría de los establos de la zona, se recomienda el control del acceso de los canes a los establecimientos lecheros en el valle del Mantaro.The neosporosis is an emergent disease, and considered as an important cause of abortion in cattle and a cause of neuromuscular disorders in dogs. The aim of the present study was to determine the seroprevalence of Neospora caninum in dogs of dairy farms in the left zone of the valley of Mantaro. A total of 24 serum samples of dogs living in and in the vicinity of 24 dairy farms of the provinces of Huancayo, Jauja and Concepcion were evaluated. The seroprevalence of antibodies against N. caninum was 19.4 ± 7.0% (24/124) in a dilution of 1:50, using the indirect immunofluorescense test. The percentage of farms having at least one infected dog was 62.5% (15/24). Statistical relationships between the rate of infection and the geographical location (province), age, sex, and origin (in and closeby the farm) did not exist. These results showed that dogs in the valley of Mantaro presented a moderate seroprevalence of N. caninum; and considering that the infection is present in most dairy farms of the valley, is recommended to limit the access of dogs to dairy farms in the valley

    Resistance to anthelmintics and prevalence of bovine fasciolosis in dairy farms in Jauja, Peru.

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    El objetivo del estudio fue determinar la prevalencia de Fasciola hepatica mediante exámenes coprológicos en el ganado bovino del distrito de Huertas, provincia de Jauja- Junín, y evaluar la eficacia de dos fasciolicidas ampliamente utilizados en la zona: triclabendazol (TBCZ) y albendazol (ABZ). Se trabajó con 387 vacas de 30 establos durante la época de lluvias. Se colectaron muestras de heces directamente del recto y se analizaron mediante los métodos de sedimentación espontánea y de Mc Master modificado. La prevalencia de F. hepatica fue de 38.2% con cargas promedio de 16 hpg (1-197 hpg). Asimismo, 26 establos (86.7%) resultaron positivos a F. hepatica. En la evaluación de resistencia a las drogas se empleó la prueba de reducción de recuento de huevos (FECRT). Se seleccionaron 75 animales que superaron recuentos de 13 hpg y se distribuyeron aleatoriamente en dos grupos: a) TCBZ, 12 mg/kg peso vivo (n=39) y b) ABZ, 10 mg/kg peso vivo (n=33). Las drogas fueron administradas vía oral. La eficacia del TBCZ a los 7, 14, 21 y 28 días post tratamiento fue de 53.4, 53.3, 36.4 y 34.9%, respectivamente, mientras que para el ABZ fue nula en todos los casos. Se concluye que la ganadería lechera de Jauja, Junín, muestra una alta prevalencia de F. hepatica, además, de presentar resistencia del parásito al albendazol y triclabendazol.The objective of this study was to determine the prevalence of Fasciola hepatica through coprological analysis in dairy cattle in the district of Huertas, province of Junin, Peru and to evaluate the efficacy of two anthelmintics frequently used in the region: triclabendazol (TBCZ) and albendazol (ABZ). Faecal samples were collected from 387 cows in 30 farms. Samples were analysed by the spontaneous sedimentation test and the modified Mc Master test. The prevalence of F. hepatica was 38.2%, with a mean of 16 eggs per gram of faeces (epg) and a range of 1 to 197 epg. Furthermore, 26 farms (86.7%) were positive to F. hepatica. The faecal egg count reduction test (FECRT) was used for evaluating the parasite resistance to the two anthelmintics. For this, 75 animals with more than 12 epg were selected and randomly allocated to two groups: a) TCBZ, 12 mg/kg body weight (n=39) and b) ABZ, 10 mg/kg body weight (n=33). Both drugs were orally administered. The efficacy of TBCZ on days 7, 14, 21, and 28 was 53.4, 53.3, 36.4, and 34.9% respectively, whereas ABZ was zero in all cases. It is concluded that dairy cattle in Huertas, Jauja has a high prevalence of F. hepatica and the parasite shows resistance to albendazol and triclabendazol
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