1,560 research outputs found
Description of the female of Poeciloxestia plagiata (Waterhouse, 1880), and of the male of Iuati spinithorax Martins & Galileo, 2010 (Coleoptera, Cerambycidae)
Based on material recently collected in Peru (Loreto department) the female of Poeciloxestia plagiata (Waterhouse, 1880), and the male of Iuati spinithorax Martins & Galileo, 2010 are described and figured for the first time. Both species are recorded for the first time from Peru
Integration of ICT into the higher education process: The case of Colombia
This paper has as its aim to establish a pedagogical strategy aimed at supporting the integration of ICTs (Information and Communication Technologies) into the higher education process. A survey was carried out aiming focus on the analysis of teachers’ practices so that competences in ICT use at university education in Colombia could be enlarged. 81 universities answered the survey questionnaire: 51 private and 30 public, and a total of 423 lecturers from different academic disciplines. Our findings show the degree of attention paid by teachers to strengthening ICT skills in their training tasks. This research is complemented with Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis performed with 50 professionals experienced in ICT use in higher education
Description of the female of Poeciloxestia plagiata (Waterhouse, 1880), and of the male of Iuati spinithorax Martins & Galileo, 2010 (Coleoptera, Cerambycidae)
Based on material recently collected in Peru (Loreto department) the female of Poeciloxestia plagiata (Waterhouse, 1880), and the male of Iuati spinithorax Martins & Galileo, 2010 are described and figured for the first time. Both species are recorded for the first time from Peru
Comparison of two synthesis methods on the preparation of Fe, N-Co-doped TiO2 materials for degradation of pharmaceutical compounds under visible light
"In this work, we report the synthesis, characterization and photocatalytic evaluation of visible light active iron-nitrogen co-doped titanium dioxide (Fe3+-TiO2?xNx) nanostructured catalyst. Fe3+-TiO2?xNx was synthesized using two different chemical approaches: sol-gel (SG) and microwave (MW) methods. The materials were fully characterized using several techniques (SEM, UV–Vis diffuse reflectance DRS, X-ray diffraction XRD, and X-ray photoelectron spectroscopy XPS). The photocatalytic activity of the nanostructured materials synthesized by both methods was evaluated for the degradation of amoxicillin (AMX), streptomycin (STR) and diclofenac (DCF) in aqueous solution. Higher degradation efficiencies were encountered for the materials synthesized by the SG method, for instance, degradation efficiencies values of 58.61% (SG) and 46.12% (MW) were observed for AMX after 240 min of photocatalytic treatment under visible light at pH 3.5. With STR the following results removal efficiencies were obtained: 49.67% (SG) and 39.90% (MW) at pH 8. It was observed the increasing of degradation efficiencies values at longer treatment periods, i.e., after 300 min of photocatalytic treatment under visible light, AMX had a degradation efficiency value of 69.15% (MW) at pH 3.5, DCF 72.3% (MW) at pH 5, and STR 58.49% (MW) at pH 8.
On-Offer and Residual Forage in a Massai-\u3cem\u3eLeucaena\u3c/em\u3e Pasture at Different Leucaena Density
Mexican livestock producers in tropical areas are increasingly interested on the establishment of silvopastoral systems based on Leucaena (Leucaena leucocephala (Lam.) de Wit) and different tropical grasses as the Massai grass (Panicum maximum cv Massai); among questions raised on this is the importance of Leucaena density in relation to forage available. Then the objective of the study was to determine total and by species on-offer and residual forage in a grazed MassaiLeucaena pasture with different Leucaena density
Sprint performance and mechanical outputs computed with an iPhone app: Comparison with existing reference methods
The purpose of this study was to assess validity and reliability of sprint performance outcomes measured with an iPhone application (named: MySprint) and existing field methods (i.e. timing photocells and radar gun). To do this, 12 highly trained male sprinters performed 6 maximal 40-m sprints during a single session which were simultaneously timed using 7 pairs of timing photocells, a radar gun and a newly developed iPhone app based on high-speed video recording. Several split times as well as mechanical outputs computed from the model proposed by Samozino et al. [(2015). A simple method for measuring power, force, velocity properties, and mechanical effectiveness in sprint running. Scandinavian Journal of Medicine & Science in Sports. https://doi.org/10.1111/sms.12490] were then measured by each system, and values were compared for validity and reliability purposes. First, there was an almost perfect correlation between the values of time for each split of the 40-m sprint measured with MySprint and the timing photocells (r = 0.989–0.999, standard error of estimate = 0.007–0.015 s, intraclass correlation coefficient (ICC) = 1.0). Second, almost perfect associations were observed for the maximal theoretical horizontal force (F0), the maximal theoretical velocity (V0), the maximal power (Pmax) and the mechanical effectiveness (DRF – decrease in the ratio of force over acceleration) measured with the app and the radar gun (r = 0.974–0.999, ICC = 0.987–1.00). Finally, when analysing the performance outputs of the six different sprints of each athlete, almost identical levels of reliability were observed as revealed by the coefficient of variation (MySprint: CV = 0.027–0.14%; reference systems: CV = 0.028–0.11%). Results on the present study showed that sprint performance can be evaluated in a valid and reliable way using a novel iPhone app.Actividad Física y Deport
Evaluation of the energy recovery potential of thermoelectric generators in diesel engines
Thermoelectric generation is an alternative to recover some of the wasted energy trough an exhaust of the internal combustion engines. This paper assesses the performance of a thermoelectric generator with 20 modules by implementing a waffle heat exchanger. Experimental results showed a variable range of power recovery from 57.87 W to 71.13 W for B10, B5, and Diesel. The highest energy conversion efficiency of the aforementioned thermoelectric device was of 3% with the highest load and the fastest rotational speed. Also, the recovery process reduced gaseous emissions such as CO, CO2, NO, NOX, and HC. Additionally, the smoke opacity per kWh is reduced at significant levels of operations such as 2.42% when using diesel, 2.65% when using B5 and 3% when using B10. However, when using biodiesel blends, NOx emissions were increased. Overall the biodiesel resulted in a higher power recovery performance versus the diesel
Population response in the post-flood phase in San Mateo Atenco, State of Mexico
La atención concedida a la gestión del riesgo tiene la finalidad de preparar a la población, antes, durante y después de la ocurrencia de un evento catastrófico. Sin embargo la escasa cultura de la prevención asociada a una elevada vulnerabilidad física y social, repercute directamente en la magnitud de los daños. El objetivo de este trabajo es exponer las acciones y las conductas de los afectados después de la ocurrencia de una inundación, para ello, se analiza información documental y se aplica una encuesta de cien cuestionarios a la población afectada en el municipio de San Mateo Atenco. Los resultados mostraron que los afectados respondieron a la inmediatez de la contingencia con acciones básicas e individuales, que no se integraron a un proceso logístico coordinado con las instancias públicas y que han aprendido a convivir con el riesgo a tal punto que no están dispuestos al abandono de su lugar de residencia.The attention paid to risk management is intended to prepare the population, before, during and after the occurrence of a catastrophic event. However, the low culture of prevention, associated to high physical and social vulnerability increases the extent of damage. The aim of this paper is to expose the actions and behaviors of those affected after the occurrence of a flood, for this, documentary information is analyzed and a survey of a hundred questionnaires is applied to the population affected in the municipality of San Mateo Atenco. The results showed that the victims
esponded to the immediacy of the contingency with basic and individual actions, which were not incorporated into a coordinated logistic process with the public authorities and that they have earned to live with risk to such an extent that they are not willing to abandon their place of residence.Fil: Vázquez Sánchez, Martín.
Universidad Nacional Autónoma de MéxicoFil: Orozco-Hernández, María E..
Universidad Nacional Autónoma de MéxicoFil: Méndez Ramírez, José Juan.
Universidad Nacional Autónoma de Méxic
Inmovilización enzimática mediante membranas poliméricas de inclusión basadas en líquidos iónicos
[ESP] Los líquidos iónicos presentan una gran utilidad como disolventes y también como medio de reacción, debido a que tienen una presión de vapor prácticamente nula y una alta estabilidad química, mecánica y térmica, lo que permite su reutilización. Se ha desarrollado un derivado enzimático inmovilizado en membranas poliméricas de inclusión basadas en líquidos iónicos para la síntesis de esteres. [ENG] Ionic liquids are very useful solvents as well as reaction medium due to their negligible vapor pressure and high chemical, mechanical and thermal stability, which allow the reuse. An immobilized enzyme derivative in polymeric membranes based on ionic liquids has been developed for the synthesis of esters.Centro Universitario de la Defensa. Escuela de Turismo de Cartagena. Escuela Técnica Superior de Ingeniería Industrial UPCT. Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT). Escuela de Ingeniería de Caminos y Minas (EICM). Escuela de Arquitectura e Ingeniería de Edificación (ARQ&IDE). Parque Tecnológico de Fuente Álamo. Navantia. Campus Mare Nostrum. Estación Experimental Agroalimentaria Tomás Ferr
Advanced Exergy Analysis of an Integrated SOFC-Adsorption Refrigeration Power System
In this chapter, an exergy analysis applied to a solid oxide fuel cell (SOFC)/vapor adsorption refrigeration (VAR) system is presented. The influences of four significant parameters (current density, inlet fuel temperature, fuel utilization and steam-to-carbon ratio) on the exergy efficiency of both the SOFC stack and the SOFC-VAR system are investigated. In order to do so, a mathematical model is constructed in Engineering Equation Solver (EES) software to generate the simulations. The analysis shows that the calculated exergy efficiency is around 8% lower than the energy efficiency for both cases. Moreover, it is found that most of the causes of irreversibilities in the system are due to electronic and ionic conduction in the components. It is also shown that the exergy efficiency is substantially sensitive to fuel inlet temperature, which is evidenced by a bending-over behavior. Finally, in accordance with the calculated efficiency defects, the main exergy destructions are present in the heat exchangers, the SOFC, the afterburner and the generator
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