20 resultados
Resultados de la búsqueda
Mostrando 1 - 10 de 20
Ítem Corredores de conservación y herramientas de manejo del paisaje: estrategias para la generación de conectividad en mosaicos de paisaje(Ministerio de Ambiente y Desarrollo Sostenible, República de Colombia, 2012-01-01) Vargas, William GerardoEn las últimas décadas, los resultados delas investigaciones sobre conservación yproducción sostenible en paisajes ruraleshan resaltado la importancia del manejosostenible en el territorio colombiano (Galindo y Murgueitio 2003, Muriel& Kattan 2009, Vargas et al. 2009a) ,en especial en ecosistemas másintervenidos como los de la región andina.Ésta es una de las mejores opciones paralograr la conservación efectiva de unabuena proporción de la biodiversidadcolombianaÍtem Synanthropic Cockroaches (Blattidae: Periplaneta spp.) Harbor Pathogenic Leptospira in Colombia(Entomological Society of America, 2016-06-01) Bonilla, ÁlvaroLeptospirosis cases in Colombia are typically linked to peridomestic rodents; however, empirical data suggest that Leptospira-infected patients with no apparent exposure to these reservoirs are common. Cockroaches (Periplaneta spp.) have equal or greater interaction with humans than rodents, yet their potential role as carriers of Leptospira has not been assessed. We determined if pathogenic Leptospira is harbored by Periplaneta spp. in Cali (Colombia) and the variables influencing this relationship. Fifty-nine cockroaches were captured from seven sites and DNA was extracted from the body surface and digestive tract for a multiplex polymerase chain reaction, targeting genes secY and flaB. Logistic regression models and proportion tests showed a higher likelihood for Leptospira to be isolated from body surfaces (P>0.001) and from individuals inside houses (six times more likely). These findings are the first to demonstrate an association between Periplaneta spp. and Leptospira, suggesting the need to investigate the potential for cockroaches to serve as reservoirs or transport hosts for Leptospira.Ítem Spatial modeling of cutaneous leishmaniasis in the Andean region of Colombia(Fundaco Oswaldo Cruz, 2016-07-01) Pérez-Flórez, MauricioThe objective of this research was to identify environmental risk factors for cutaneous leishmaniasis (CL) in Colombia and map high-risk municipalities. The study area was the Colombian Andean region, comprising 715 rural and urban municipalities. We used 10 years of CL surveillance: 2000-2009. We used spatial-temporal analysis - conditional autoregressive Poisson random effects modelling - in a Bayesian framework to model the dependence of municipality-level incidence on land use, climate, elevation and population density. Bivariable spatial analysis identified rainforests, forests and secondary vegetation, temperature, and annual precipitation as positively associated with CL incidence. By contrast, livestock agroecosystems and temperature seasonality were negatively associated. Multivariable analysis identified land use - rainforests and agro-livestock - and climate - temperature, rainfall and temperature seasonality - as best predictors of CL. We conclude that climate and land use can be used to identify areas at high risk of CL and that this approach is potentially applicable elsewhere in Latin America.Ítem Tunable polyesterification of xylitol: from linear to crosslinked structures(John Wiley and Sons Ltd, 2017-04-01) Benitez, RicardoThe copolymerization by condensation chemistry of succinic acid and xylitol, a byproduct from the sugarcane and alcohol industry, is reported. Two methodologies were studied concerning succinic acid, with and without carboxylic acid activation, yielding crosslinked and linear low molecular weight polymers, respectively. All polymerizations were carried out at reaction times in the range from 36 to 80 h, with a molar mass ratio of 1:1 and 1:3. Linear and crosslinked polyesters were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, DSC and TGA, and structural characterization was carried out by Fourier transform infrared spectroscopy and NMR. © 2016 Society of Chemical Industry. © 2016 Society of Chemical IndustryÍtem Do thermoregulatory costs limit altitude distributions of Andean forest birds?(Blackwell Publishing Ltd, 2017-01-01) Robinson, Scott K.Along tropical mountains, species often occupy narrow altitude ranges. Numerous biotic and abiotic factors have been proposed as determinants of altitude occupancy. We measured several aspects of thermal physiology of 215 bird species across a 2·6-km altitude gradient in the Peruvian Andes. We predicted that highland species would show adaptation to the colder high-altitude climate and that energy costs of thermoregulation might limit upslope dispersal of lowland natives. We found reductions in thermal conductance, body temperature and lower critical temperature in highland birds compared with lowland species. These combine to make highland natives more resistant to heat loss. We did not find convincing evidence that acute thermal limits or energy costs of thermoregulation constrained altitude distributions.Ítem Guía para la elaboración de planes de manejo de Reservas Naturales de la Sociedad Civil(Asociación Red Colombiana de Reservas Naturales de la Sociedad Civil, RESNATUR, 2009-01-01) Asociación Red Colombiana de Reservas Naturales de la Sociedad Civil, RESNATURLa conservación de la biodiversidad y los recursos naturales en predios de propiedad privada es un manejo que dan sus dueños con alguna intención. Las razones varían pero lo importante es lograr esta intención a largo plazo, disfrutando lo que se hace mientras se aprende, haciendo un aporte con esta labor tan importante para la Tierra y sus habitantes. Desde las instituciones públicas y privadas que apoyan la conservación, se ha evidenciado la necesidad de acompañar y guiar a los propietarios de estos predios en conservación, que suelen llamarse Reservas Naturales de la Sociedad Civil, brindando pautas temáticas y de manejo que han sido exitosas en su implementación. En Colombia, quisimos construir colectivamente entre autoridades ambientales, como Parques Nacionales Naturales de Colombia y las Corporaciones Autónomas Regionales; organizaciones privadas como las redes de reservas y organizaciones ambientales internacionales, y propietarios de reservas, una guía que permita a los propietarios plantearse algunas preguntas, proponer algunas soluciones y presentar muchos caminos como opciones para continuar construyendo reservas que se destaquen por su manejo, y se diferencian de otros predios privados por su aporte al bienestar de sus habitantes mientras aportan bienestar para el mundo.Ítem Activity of (2E)-3-(2, 3-dimetoxifenil)-1-(4-metilfenil) prop-2-en-1-ona in the presence of poli(maleic acid-co-2-vinyl-pyrrolidone) on a β-lactamase producing clinical isolate of Staphylococcus aureus(Universidad de Antioquia, 2012-01-01) Salamanca Mejía, Constaín HugoDue to the current problem of resistance to b-lactam antibiotics, it has become necessary, in search of a solution, to work with new molecules with pharmacological potential, and to use novel polymeric systems as matrices or pharmaceutical excipients. Objective: To evaluate the antibiotic activity of ampicillin combined with a synthetic chalcone-type compound, the (2E)-3-(2,3-dimethoxyphenyl)-1-(4- methylphenyl) prop-2-en-1-one, on a clinical isolate of penicillin-resistant Staphylococcus aureus in the presence of a water soluble polymer matrix known as poly(maleic acid-co-2-vinyl-pyrrolidone). Materials and methods: The synthetic compound and the polymeric matrix were obtained by previously described methods. Tests for antibiotic activity against the strain of penicillin-resistant Staphylococcus aureus were done by the broth dilution technique which provided the minimal inhibitory concentrations of the compounds tested. Results: The chalcone-ampicillin mix shows lesser antibiotic effect than the ampicillin-sulbactam used as referent. However, when such mix is combined with the polymer matrix, antibiotic activity significantly increases as evidenced by decrease in the minimal inhibitory concentration with respect to the ampicillin-sulbactam referent.Ítem Estudio del efecto de los sistemas poliméricos PAM-18 K2 y PAM-18 Na2 sobre los perfiles de disolución de comprimidos de ampicilina(Universidad Icesi, 2013-01-01) Pineda Camero, Diego; Salamanca Mejía, Constain Hugo; Asesor TesisThe present grade project is part of an investigation work with a bigger scope, which is focused in the research of the characterization of physicochemical properties in aqueous solutions of polymer materials with amphiphilic characteristics, with the purpose to evaluate their potential as novel pharmaceutical matrices capable to decrease the biodegradability of betalactamic drugs. Specifically, in this grade project, the variation in dissolution profiles of commercial tablets of the betalactamic drug ampicillin in its trihydrate form was evaluated, in presence of the polymer materials PAM-18Na2, PAM-18 K2 and Eudragit E-100 Chloride in media with physiologic conditions of pH and ionic strength modified by action from the polymeric systems in dispersion, with pH values of 1,2 and 7,4 and ionic strength of 0,15 M in a temperature of 37°C.Ítem Estudios viscosimétricos para evaluar el fenómeno de asociación entre el EUDRAGIT e-100® modificado y la carbamazepina en medio acuoso.(Universidad Icesi, 2014-01-01) Barrera Contreras, Angélica EstefaniaThis project intended to assess the phenomenon of chemical association of the polymeric material, Hydrochloride Eudragit E-100, with a reference drug, as carbamazepine, using a methodology of capillary viscometry, previously standardized. A capillary viscometer known as Oswald or Ubbelohde viscometer, whose experimental measurement parameter is the flow time, or run-time was used. The run-time values have an indirect relationship with the relative viscosity, thereby allowing for differences between the relative viscosities of the polymer solutions Hydrochloride Eudragit E-100 in the presence and absence of drug. The determination of the run-time values were taken at 37 ° C, and pH values corresponding to 1.2, 2, 4, 6, 7.4, 8, and 10. We found that the standardized method showed a property repeatability and intermediate precision. Also, an effect of concentration and ionic strength of the medium in the relative viscosities of the ionomer solutions was obtained. And, a conformational transition phenomenon of Hydrochloride Eudragit E-100 in function of the pH of the medium was checked. This made possible to obtain a marked effect on the rheological behavior of the polymer solutions in the presence and absence of carbamazepine, thereby assuming a potential phenomenon of polymer-drug association. Moreover, we obtained that carbamazepine or model drug does not affect the viscosity of the aqueous media.Ítem Evaluación de la diversidad de arañas como indicadoras de la efectividad de las estrategias de restauración implementadas en el corredor biologico Barbas - Bremen, Filandia (Quindío-Colombia)(Universidad Icesi, 2014-01-01) Ortiz Movliav, Carolina; Vargas, William Gerardo; Asesor TesisSpiders are a diverse and abundant group in all terrestrial ecosystems. Their communities are influenced by the type of habitat, land use, and plant architecture, so they are well accepted in ecological and environmental studies. They are generalist predators that have a major impact on the regulation of herbivore populations, also they are easy to collect and identify. The objective of this research was to evaluate the effectiveness of restoration strategies implemented in biological corridors connecting the Barbas River Canyon and The Forest Preserve of Bremen (Filandia-Quindío), through the measure of the diversity of spiders. For this, samples were taken in three biological corridors “Los Monos”, “Las Pavas” and “Los Colibríes”, in two forest fragments, Barbas and Bremen and in a paddock near to the corridors. Sampling was conducted during day sessions, and during dry and rainy seasons over one year period, using three methods: hand collecting (Looking up and looking down), sweeping with entomological net and using a beating trap. After 96 sampling unites, 736 individual were identified grouped into 18 families and 126 morphospecies.