17 research outputs found
4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica
Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil.
El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país.
La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica.
Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas
Preparación de una Membrana Híbrida a partir de Fibrillas de Proteína de Suero y Carbón Activado para Eliminar Mercurio y Cromo del Agua
21 páginasWater contamination by mercury and chromium has a direct effect in human health. A promising technology to remove heavy metals by membrane filtration is the use of hybrid membranes produced with whey protein fibrils (WPF) and activated carbon (AC). In this study, the best conditions to produce WPF by heat treatment were determined to maximize the removal of mercury and chromium from water using a central composed design. The results indicated that the best conditions to prepare WPF were 74 °C, 7 h and 3.8% of whey protein with adsorption capacities of 25 and 18 mg/g and removal efficiencies of 81 and 57% for mercury and chromium, respectively. WPF and AC were used to prepare a hybrid membrane that was characterized using transmission electron microscopy, atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller surface area measurements. Batch filtration experiments were performed with the hybrid membrane for chromium and mercury removal at 25, 50 and 100 mg/L to determine its adsorption capacities. A high performance of the hybrid membrane was demonstrated removing efficiently mercury and chromium from water, thus supporting more than ten filtration cycles.La contaminación del agua por mercurio y cromo tiene un efecto directo en la salud humana. Una tecnología prometedora para eliminar metales pesados mediante filtración por membrana es el uso de membranas híbridas producidas con fibrillas de proteína de suero (WPF) y carbón activado (AC). En este estudio, se determinaron las mejores condiciones para producir WPF mediante tratamiento térmico para maximizar la eliminación de mercurio y cromo del agua utilizando un diseño compuesto central. Los resultados indicaron que las mejores condiciones para preparar WPF fueron 74 °C, 7 h y 3.8 % de proteína de suero con capacidades de adsorción de 25 y 18 mg/g y eficiencias de remoción de 81 y 57 % para mercurio y cromo, respectivamente. WPF y AC se utilizaron para preparar una membrana híbrida que se caracterizó mediante microscopía electrónica de transmisión, microscopía de fuerza atómica, microscopía electrónica de barrido, espectroscopía infrarroja transformada de Fourier y mediciones del área superficial de Brunauer-Emmett-Teller. Se realizaron experimentos de filtración por lotes con la membrana híbrida para la eliminación de cromo y mercurio a 25, 50 y 100 mg/L para determinar su capacidad de adsorción. Se demostró un alto desempeño de la membrana híbrida removiendo eficientemente mercurio y cromo del agua, soportando así más de diez ciclos de filtración
Preparation and Characterization of an Electrospun Whey Protein/Polycaprolactone Nanofiber Membrane for Chromium Removal from Water
Chromium pollution represents a worldwide concern due to its high toxicity and bioaccumulation in organisms and ecosystems. An interesting material to remove metal ions from water is a whey-protein-based material elaborated by electrospinning, which is an emerging method to produce adsorbent membranes with diverse applications. The aim of this study was to prepare an adsorbent membrane of whey protein isolate (WPI) and polycaprolactone (PCL) by electrospinning to remove chromium ions from water. The adsorbent membrane was synthesized by a central composed design denaturing WPI using 2-Mercaptoethanol and mixing it with PCL to produce electrospun nanofibers. The adsorbent membrane was characterized by denaturation, Scanning Electron Microscope, Fourier-Transform Infrared Spectroscopy, Contact Angle, Thermogravimetric Analysis, and X-ray Photoelectron Spectrometry. The adsorption properties of this membrane were assessed in the removal of chromium. The removal performance of the membrane was enhanced by an increase in temperature showing an endothermic adsorption process. The adsorption process of chromium ions onto the nanofiber membrane followed the Sips adsorption isotherm, while the adsorption kinetics followed a pseudo-second kinetics where the maximum adsorption capacity was 31.0 mg/g at 30 °C and pH 2. This work provides a novel method to fabricate a hybrid membrane with amyloid-type fibrils of WPI and PCL, which is a promising adsorbent to remove heavy metal ions from water
China en América Latina y el Caribe : escenarios estratégicos subregionales
América Latina está inmersa en una etapa de transición, en el que confluyen distintos procesos en una lógica que no adquiere clara conceptualización. Se trataría de un período postliberal o una etapa post hegemónica que se puede imaginar desde la existencia de una serie de indicadores de un cambio en el escenario. Entre estos destacan la prioridad de la agenda política en el multilateralismo regional que agrupa al conjunto de América Latina y el Caribe y la visión de la integración comercial como un instrumento, no como un fin; la recuperación de la agenda del desarrollo; la asignación de un mayor papel al Estado; mayor énfasis en la agenda positiva de la integración
Maternal fetal transmission of Trypanosoma cruzi: A problem of public health little studied in Mexico
The first case of neonatal Chagas was reported in Mexico in 1998, but there have been no studies since then. Therefore, we investigated the rates of congenital infection of Trypanosoma cruzi by examining the seroprevalence among 1448 pregnant women in Oaxaca, Jalisco and Mexico City. We performed ELISAs to screen for recombinant and total antigens in mothers, and examined the frequency of congenital T. cruzi transmission by PCR with cord blood and antibody testing in children when they reached two years old. Our results showed that the prevalence of infection in pregnant women was 7.32% (106/1448) overall, and 4.4% (35/794) in Oaxaca, 12.02% (67/557) in Jalisco and 4.12% (4/97) in the Mexico City. In Oaxaca, T. cruzi infection was detected by PCR in 20% (7/35) of infants born to seroreactive mothers and 11.9% (8/67) in Jalisco. No infections were identified in infants from the Mexico City. From these only eleven serological follow up their children are agree to take blood. Therefore, the maternal-fetal overall transmission rate was 4.08% (4/98) in Oaxaca and 9.1% (3/33) in Jalisco 1.5% (1/65) children with positive serology were given specific treatment Chagas. In conclusion, these are the first reports of the rates of congenital Chagas disease in Mexico. The seroprevalence was higher in mothers from Jalisco, and could be related to that there is not the periodic fumigation of the transmitting vector performed in that state. The high rates of maternal-fetal transmission found in Oaxaca could be related to the differences of pathogenicity of trypanosome. No association between both the rate of congenital transmission and the gynecologic anthropometric data was observed. © 2012 Elsevier Inc.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
As relações Colômbia, países vizinhos e Estados Unidos: visões em torno da agenda de segurança Relations between Colombia, its neighbours and the United States: views on the Security Agenda
Este artigo trabalha a tese de que a agenda de segurança dos EUA para Colômbia, que adquire expressão concreta em mecanismos como o Plano Colômbia e a Iniciativa Regional Andina, continuará sendo o eixo central da política de segurança na região sul-americana. No entanto, a noção de segurança que têm em mente os decisions makers dos EUA no caso colombiano reflete uma visão nas percepções de ameaças na que se misturam fortemente elementos novos ("as novas ameaças"), como o tráfico de drogas e fatores clássicos.<br>This article works the thesis that the security agenda of the USA for Colombia, that acquires a concrete expression in mechanisms like the Colombia Plan and the Andean Regional Initiative, will remain as the central axis of the security policy in the South-American region. However, the notion of security that the decision makers of the USA have in mind in the Colombian case reflects a vision focused on the perceptions of threat in which new elements ("the new threats"), such as traffic, and classical factors are mixed
Designing connected marine reserves in the face of global warming
Marine reserves are widely used to protect species important for conservation and fisheries and to help maintain ecological processes that sustain their populations, including recruitment and dispersal. Achieving these goals requires well-connected networks of marine reserves that maximize larval connectivity, thus allowing exchanges between populations and recolonization after local disturbances. However, global warming can disrupt connectivity by shortening potential dispersal pathways through changes in larval physiology. These changes can compromise the performance of marine reserve networks, thus requiring adjusting their design to account for ocean warming. To date, empirical approaches to marine prioritization have not considered larval connectivity as affected by global warming. Here, we develop a framework for designing marine reserve networks that integrates graph theory and changes in larval connectivity due to potential reductions in planktonic larval duration (PLD) associated with ocean warming, given current socioeconomic constraints. Using the Gulf of California as case study, we assess the benefits and costs of adjusting networks to account for connectivity, with and without ocean warming. We compare reserve networks designed to achieve representation of species and ecosystems with networks designed to also maximize connectivity under current and future ocean-warming scenarios. Our results indicate that current larval connectivity could be reduced significantly under ocean warming because of shortened PLDs. Given the potential changes in connectivity, we show that our graph-theoretical approach based on centrality (eigenvector and distance-weighted fragmentation) of habitat patches can help design better-connected marine reserve networks for the future with equivalent costs. We found that maintaining dispersal connectivity incidentally through representation-only reserve design is unlikely, particularly in regions with strong asymmetric patterns of dispersal connectivity. Our results support previous studies suggesting that, given potential reductions in PLD due to ocean warming, future marine reserve networks would require more and/or larger reserves in closer proximity to maintain larval connectivity
Haematological Alterations Associated with Selected Vector-Borne Infections and Exposure in Dogs from Pereira, Risaralda, Colombia
Infections due to Ehrlichia, Anaplasma, Dirofilaria, Mycoplasma, Babesia and Hepatozoon continue to be highly prevalent in dogs, especially in tropical and subtropical areas, where vectors of many of them are present. However, many clinical aspects of dogs have not been characterized in detail, including assessing the haematological alterations associated with them, particularly in Colombia and Latin America. A group of 100 dogs with Ehrlichia, Anaplasma, Dirofilaria, Mycoplasma, Babesia and Hepatozoon infections/exposure were assessed by blood smear serology (SNAP4DX) and PCR in Pereira, Colombia. We performed blood counts to evaluate anaemia, leukopenia/leukocytosis, neutropenia, neutrophilia, lymphopenia/lymphocytosis, monocytosis, eosinophilia, and thrombocytopenia, among other alterations. Bivariate analyses were performed on Stata®14, with significant p Ehrlichia 75%), and 89% presented clinical alterations. A total of 100% showed anaemia, 70% thrombocytopenia, 61% monocytosis, and 47% neutropenia, among other alterations. Additionally, 11% presented pancytopenia and 59% bicytopenia. The median platelet count was lower in infected dogs (126,000 cells/μL) versus non-infected (221,000 cells/μL) (p = 0.003). Thrombocytopenia was higher among infected dogs (75%) versus non-infected (40%) (p = 0.006), with a 91% positive predictive value for infection. Median neutrophil count was lower in infected dogs (6591 cells/μL) versus non-infected (8804 cells/μL) (p = 0.013). Lymphocytosis occurred only among those infected (27%) (p = 0.022). Leukopenia was only observed among infected dogs (13%). Pancytopenia was only observed among infected dogs. Ehrlichiosis and other hematic infections have led to a significant burden of haematological alterations on infected dogs, including pancytopenia in a tenth of them, most with thrombocytopenia and all anemic