12 research outputs found
Policies evaluation to reduce greenhouse gas emissions in road freight transport in Colombia
La temperatura de la superficie de la tierra se ha elevado en 1°C en comparación con la era preindustrial debido al aumento de las concentraciones de gases de efecto invernadero, consecuencia de las actividades productivas del ser humano. Esta situación ha traído consigo cambios en los ciclos naturales, en los patrones del clima y efectos colaterales que pueden poner en riesgo la vida de todas las especies del planeta. Adicional a los cambios que se pueden percibir actualmente, expertos pronostican un futuro aún más complejo, debido a que las personas cada vez emiten más CO2 a la atmósfera. Entes gubernamentales internacionales y gran cantidad de países, han propuesto acuerdos para mitigar la cantidad de emisiones, con el fin de desacelerar el Cambio Climático y otorgar más tiempo para adaptarse a dichos cambios. Colombia es una de las naciones que se ha comprometido a reducir sus emisiones en todos los sectores de su economía a 2030, sobre todo en aquellos que más generan gases de efecto invernadero, como el sector transporte, puntualmente el de carga carretero, el cual genera el 36% de las emisiones del sector. Esta investigación, pretende hallar y evaluar estrategias y políticas que pertinentes para la reducción de las emisiones de dióxido de carbono equivalente en el país mediante la metodología de dinámica de sistemas, en dirección a los compromisos adquiridos por la nación. Al realizar la evaluación y el análisis en el modelo de simulación, se evidencia que una combinación de diferentes políticas y escenarios es el caso en el que se perciben resultados más favorables. Un aumento de la participación del modo férreo, la incursión de nuevas tecnologías vehiculares y la regulación de la edad de la flota, son elementos necesarios para que la actividad económica de transporte carretero reduzca sus emisiones en las proporciones pactadas, sea más sostenible y eficiente.The overall surface temperature of the earth has been raised by 1 ° C since the preindustrial time due to greenhouse gas concentration increment as a consequence of the human productive activities, bringing with it several changes in natural cycles, the climate pattern and collateral effects that could place the life of all the species on the planet in severe danger. Experts predict a tough future, with events even worse than those the planet is going through now, caused by the CO2 human emissions, which are still increasing. International governmental entities and nations have been compromised to mitigate those emissions trying to decelerate Climate Change bringing more time to make plans for the adaptation. Colombia is one of the countries who has been committed to reducing greenhouse gas emissions in its whole economy by 2030 especially in those sectors that are more polluting as road freight transportation activity which generates 36% of the emissions in this transport sector. This research pretends to find and assess strategies and policies that contribute reducing equivalent carbon dioxide emissions with a system dynamics methodology approach in line to reach the targets of the nation. The model simulation shows that a combination of initiatives and scenarios is the case with better results. An increase of rail mode share on the modal shift, the penetration of new vehicular technologies and the regulation of the fleet age are necessary elements to reduce the emissions in this activity, achieving sustainability and efficiency.Transporte de carga carretera en Colombia y dinámica de sistemasLínea de Investigación: Transporte, Cambio Climático, Eficiencia EnergéticaMaestrí
A Career in Catalysis: Avelino Corma
As one of the most influential scientists in the field of heterogeneous catalysis and materials science, Prof. Avelino Corma has made significant contributions in many diverse fields, spanning over solid catalysts for petrochemistry, solid catalysts for production of fine chemicals, synthesis of microporous and mesoporous materials, development of inorganic-organic hybrid materials, supported metal catalysts (from isolated metal atoms to nanoclusters and nanoparticles) and photochemistry with solid materials. These experimental approaches are complemented with characterization of solid materials with advanced spectroscopy and microscopy techniques as well as theoretical calculations/modeling. The aim of this Account is to overview Avelino's distinguished scientific career and highlight the most remarkable achievements made in his research activities during >40 years. We attempt to show the evolution of Avelino's research topics in his group throughout his career and the approaches that Avelino has chosen to tackle the challenges encountered. The research paradigm developed by Avelino and his team can be inspiring to the researchers in the field of materials science who are striving to translate the knowledge generated in fundamental studies into practical applications for addressing the new scientific challenges encountered in building a sustainable world
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Estudio de egresados, un indicador de pertinencia y calidad. Estudio de caso
El presente trabajo presenta un estudio de egresados para valorar la pertinencia y calidad del programa educativo de la carrera de ingeniero bioquímico ambiental en la Universidad Autónoma de Campeche, empleando el instrumento de acopio de información propuesto por la Asociación Nacional de Universidades e Instituciones de Educación Superior, el cual fue diseñado para medir la pertinencia y la calidad de las instituciones educativas en contraste con algunas adecuaciones adaptadas al contexto de su aplicación. Para ello, se consideraron 51 alumnos egresados de cinco generaciones (2004 - 2009). Los resultados muestran que 64 % de los egresados ejercen una actividad remunerada en el mercado laboral, siendo los porcentajes más altos los de jefes de oficina, supervisores y funcionarios públicos; 46.2 % afirma que existe total coincidencia de su actividad laboral con sus estudios de licenciatura, sin embargo, 51.9 % manifestó que no labora en su área de estudio. Este porcentaje habla de la necesidad de rediseñar el plan de estudios para que se considere un programa educativo pertinente y de calidad.Dicho seguimiento de egresados está considerado dentro del rubro “vinculación - extensión” por el comité acreditador de este programa educativo, el CACEB
Unusually Low Heat of Adsorption of CO2 on AlPO and SAPO Molecular Sieves
We acknowledge the Spanish Ministry of Sciences, Innovation
and Universities (MCIU), State Research Agency (AEI), and
the European Fund for Regional Development (FEDER)
for their funding via projects Multi2HYcat (EU-Horizon
2020 funded project under grant agreement no. 720783), Program Severo Ochoa SEV-2016-0683 and RTI2018-101033-
B-I00 and also Fundación Ramón Areces for funding through
a research contract (CIVP18A3908). EP-B thanks the MCIU
for his grant (FPU15/01602). NG-C thanks MCIU for her
grant (BES-2016-078178)
Data from: Complex phylogeographic patterns indicate Central American origin of two widespread Mesoamerican Quercus (Fagaceae) species
The northern Neotropical region is characterized by a heterogeneous geological and climatic history. Recent studies have shown contrasting patterns regarding the role of geographic elements as barriers that could have determined phylogeographic structure in various species. Recently, the phylogeography and biogeography of Quercus species have been studied intensively, and the patterns observed so far suggest contrasting evolutionary histories for Neotropical species in comparison with their Holarctic relatives. The goal of this study was to describe the phylogeographic structure of two Neotropical oak species (Quercus insignis and Quercus sapotifolia) in the context of the geological and palaeoclimatic history of the northern Neotropics. Populations through the distribution range of both species were collected and characterized using nine chloroplast DNA microsatellite loci. Both oak species showed high levels of genetic diversity and strong phylogeographic structure. The distribution of genetic variation in Q. insignis suggested an influence of two major barriers, the Isthmus of Tehuantepec and the Nicaraguan Depression, while Q. sapotifolia exhibited a genetic structure defined by the heterogeneity of the Chortis highlands. The haplotype networks of both species indicated complex histories, suggesting that colonization from the Sierra Madre de Chiapas to central Mexico and from the north of the Nicaraguan Depression to the Costa Rican mountains may have occurred during different stages, and apparently more than one time. In conclusion, the phylogeographic structure of Neotropical oak species seems to be defined by a combination of geological and climatic events
Complex phylogeographic patterns indicate Central American origin of two widespread Mesoamerican Quercus (Fagaceae) species
The northern Neotropical region is characterized by a heterogeneous geological and climatic history. Recent studies have shown contrasting patterns regarding the role of geographic elements as barriers that could have determined phylogeographic structure in various species. Recently, the phylogeography and biogeography of Quercus species have been studied intensively, and the patterns observed so far suggest contrasting evolutionary histories for Neotropical species in comparison with their Holarctic relatives. The goal of this study was to describe the phylogeographic structure of two Neotropical oak species (Quercus insignis and Quercus sapotifolia) in the context of the geological and palaeoclimatic history of the northern Neotropics. Populations through the distribution range of both species were collected and characterized using nine chloroplast DNA microsatellite loci. Both oak species showed high levels of genetic diversity and strong phylogeographic structure. The distribution of genetic variation in Q. insignis suggested an influence of two major barriers, the Isthmus of Tehuantepec and the Nicaraguan Depression, while Q. sapotifolia exhibited a genetic structure defined by the heterogeneity of the Chortis highlands. The haplotype networks of both species indicated complex histories, suggesting that colonization from the Sierra Madre de Chiapas to central Mexico and from the north of the Nicaraguan Depression to the Costa Rican mountains may have occurred during different stages, and apparently more than one time. In conclusion, the phylogeographic structure of Neotropical oak species seems to be defined by a combination of geological and climatic events.Programa de Becas Posdoctorales DGAPA, UNAMRed Latinoamericana de Botánica-Andrew W. Mellon Foundation GrantPAPIIT IV201015CONACYT 240136 grantsUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
Non-invasive oxygenation support in acutely hypoxemic COVID-19 patients admitted to the ICU : a multicenter observational retrospective study
Background: Non-invasive oxygenation strategies have a prominent role in the treatment of acute hypoxemic respiratory failure during the coronavirus disease 2019 (COVID-19). While the efficacy of these therapies has been studied in hospitalized patients with COVID-19, the clinical outcomes associated with oxygen masks, high-flow oxygen therapy by nasal cannula and non-invasive mechanical ventilation in critically ill intensive care unit (ICU) patients remain unclear. Methods: In this retrospective study, we used the best of nine covariate balancing algorithms on all baseline covariates in critically ill COVID-19 patients supported with > 10 L of supplemental oxygen at one of the 26 participating ICUs in Catalonia, Spain, between March 14 and April 15, 2020. Results: Of the 1093 non-invasively oxygenated patients at ICU admission treated with one of the three stand-alone non-invasive oxygenation strategies, 897 (82%) required endotracheal intubation and 310 (28%) died during the ICU stay. High-flow oxygen therapy by nasal cannula (n = 439) and non-invasive mechanical ventilation (n = 101) were associated with a lower rate of endotracheal intubation (70% and 88%, respectively) than oxygen masks (n = 553 and 91% intubated), p < 0.001. Compared to oxygen masks, high-flow oxygen therapy by nasal cannula was associated with lower ICU mortality (hazard ratio 0.75 [95% CI 0.58-0.98), and the hazard ratio for ICU mortality was 1.21 [95% CI 0.80-1.83] for non-invasive mechanical ventilation. Conclusion: In critically ill COVID-19 ICU patients and, in the absence of conclusive data, high-flow oxygen therapy by nasal cannula may be the approach of choice as the primary non-invasive oxygenation support strategy
Compilación de Proyectos de Investigacion de 1984-2002
Instituto Politecnico Nacional. UPIICS