Universidad de la Salle

Las siguientes son publicaciones realizadas por los investigadores de la Universidad de La Salle en Salud y Bienestar Animal.

Bayesian-Based Ensemble Source Apportionment of PM2.5 

A Bayesian source apportionment (SA) method is developed to provide source impact estimates and associated uncertainties. Bayesian-based ensemble averaging of multiple models provides new source profiles for use in a chemical mass balance (CMB) SA of fine particulate matter (PM2.5). The approach estimates source impacts and their uncertainties by using a short-term application of four individual SA methods: three receptor-based models and one chemical transport model. The method is used to estimate two seasonal distributions of source profiles that are used in SA for a long-term PM2.5 data set. For each day in a long-term PM2.5 data set, 10 source profiles are sampled from these distributions and used in a CMB application, resulting in 10 SA results for each day. This formulation results in a distribution of daily source impacts rather than a single value. The average and standard deviation of the distribution are used as the final estimate of source impact and a measure of uncertainty, respectively. The Bayesian-based source impacts for biomass burning correlate better with observed levoglucosan (R-2 = 0.66) and water-soluble potassium (R-2 = 0.63) than source impacts estimated using more traditional methods and more closely agrees with observed total mass. The Bayesian approach also captures the expected seasonal variation of biomass burning and secondary impacts and results in fewer days with sources having zero impact. Sensitivity analysis found that using non-informative prior weighting performed better than using weighting based on method-derived uncertainties. This approach can be applied to long-term data sets from speciation network sites of the United States Environmental Protection Agency (U.S. EPA). In addition to providing results that are more consistent with independent observations and known emission sources being present, the distributions of source impacts can be used in epidemiologic analyses to estimate uncertainties associated with the SA results. 

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Anthropophilic biting behaviour of Anopheles (Kerteszia) neivai Howard, Dyar & Knab associated with Fishermen's activities in a malaria-endemic area in the Colombian Pacific 

On the southwest Pacific Coast of Colombia, a field study was initiated to determine the human-vector association between Anopheles (Kerteszia) neivai and fishermen, including their nearby houses. Mosquitoes were collected over 24-h periods from mangrove swamps, marshlands and fishing vessels in three locations, as well as in and around the houses of fishermen. A total of 6,382 mosquitoes were collected. An. neivai was most abundant in mangroves and fishing canoes (90.8%), while Anopheles albimanus was found indoors (82%) and outdoors (73%). One An. neivai and one An. albimanus collected during fishing activities in canoes were positive for Plasmodium vivax, whereas one female An. neivai collected in a mangrove was positive for P. vivax. In the mangroves and fishing canoes, An. neivai demonstrated biting activity throughout the day, peaking between 06: 00 pm-07: 00 pm and there were two minor peaks at dusk and dawn. These peaks coincided with fishing activities in the marshlands and mangroves, a situation that places the fishermen at risk of contracting malaria when they are performing their daily activities. It is recommended that protective measures be implemented to reduce the risk that fishermen will contract malaria. 

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Grouping protocol in shelters 

Dog population dynamics in shelters often requires the grouping of individuals, and changes to the composition of those groups. We developed a protocol to maximize the positive effects and reduce the negative effects associated with grouping dogs. Twenty-three neutered dogs that had to be grouped participated in the study. Fifteen were adult females, 7 were adult males, and 1 was a juvenile female. The protocol was divided into phases that allowed the use of environmental enrichment (occupational, social, nutritional, and sensorial) and behavioral modification (systematic desensitization and counter-conditioning). There were no fights involving bites during the formation of groups. In 5 (18.5%) of formed pairs, we observed unidirectional manifestations of aggression that did not involve physical contact. Three pairs (10%) could not be formed because we saw bidirectional aggression manifestation involving physical contact but no bites. The proposed protocol is a viable alternative to improve grouping of dogs in the context of shelters. The protocol also has the potential to promote wellness, enhance production of desirable behaviors, and decrease the presence of behavioral problems. (C) 2013 Elsevier Inc. All rights reserved. 

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