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ponencia
Presentación oral ofrecida en el XXVlllth URSI General Assembly 2005, New Delhi, 23-29 October 2005. 56.
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objeto de conferencia
it is well known that an economy based on knowledge has a strong potential for human capital. In this sense, universities have a key role in student's professional development and performance, as well as to increase the number of professional population in science, technology, engineer, and mathematics. The aim of the present study is to obtain student's individual, structural and external characteristics by considering their context, which represents a condition that shape student's interest, persistence and goals in computing engineering discipline through career development. To accomplish this, we used self-reports based on Social Cognitive Career Theory in a sample of system engineering students (n=270) from three universities in the north of Lima. In addition to this, we evaluate the model through Structural Equation Modeling (SEM) under the partial least squared (PLS-SEM) approach....
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objeto de conferencia
Traducción realizada con la versión gratuita del traductor www.DeepL.com/Translator
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artículo
The effect of carboxymethylation and NH4I incorporation on the molecular dynamics of carrageenan films was studied. Broadband Dielectric Spectroscopy (BDS) assessed the presence of α and β relaxation processes. The effect of NH4I content was analyzed using the Havriliak-Negami model and parameterizing the temperature dependence of the relaxation times according to the Vogel-Fulcher-Tammann-Hesse (VFTH) equation. The glass transition temperature was found to decrease with the increase of NH4I content. These results suggest that carboxymethylation and the salt doping treatment increase the molecular mobility of NH4+ ions, making the films suitable for the development of solid electrolytes for energy storage applications. © 2018, © 2018 Taylor & Francis Group, LLC.
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artículo
Zinc stannate (ZTO) was synthesised hydrothermally at 200 ºC for 16 h. The obtained material was characterized using X-ray diffraction (XRD) and transmission electron microscope (TEM). The main cristallite size was 40 nm calculated from its X-ray diffractogram. The photocatalytic activity of this material was tested by measuring the decomposition of an aqueous solution of methyl orange under UV light illumination. The result shows a degradation of 30% of the dye after 60 min of treatment.
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artículo
The purpose of this research is to evaluate the performance of production of alginic acid laboratory scale in order to compare the results of the kinds of brown algae: Lessonia trabeculata vs. Macrocystis pyrifera. The results indicate higher performance in the production of acid alginic from Macrocystis pyrifera regarding Lessonia trabeculata.
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artículo
We evaluate the maca antioxidant effect in albino rats to observe its influence in the development of osteoporosis. Twenty five (25) four month female albino rats were used and divided ¡nto five groups. Gl a control group and four sample groups (G2, G3, G4 and G5) were forced to have osteoporosis with heparina 2U / gl every other day for a thrce week period, at the same time they were given antioxidants (G3) and natural products (maca, G4 and soya, GS) where G2 the osteoporosis c( ntrol group. At the end of thi5 period blood and urine samples were taken for the analysis of catalase(CAT) and dismutase super oxide (SOD) to evaluate the antioxidant effect and Hidroxiprolina urine and calcium as indicators in the lose out of calcium (resorbtion osea). The G2 which presented osteoporosis showed an increase in their antioxidants enzymes while maca was the natural product which presented reaso...
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artículo
The current study is an evaluation of Vitamin A supplement diet in female white mice Balb C53 inoculated with Sarcoma 180. The oral administration of a dose of 200 IU per day of Vitamin A in mice inoculated with sarcoma and divided in two groups, obtained a greater group B (vitamin A supplemented diet) mice survival curve than group A (normal diet) mice survival curve; however more studies are necessary to get a statistical significance. Liver concentration of catalasa was also quantified in three groups of mice: (1) healthy mice with normal diet; (2) sarcoma inoculated mice with normal diet; an (3) sarcoma inoculated mice with vitamin A supplement díet. It showed a significant difference of concentration of catalasa in group 2 in relation to group 1, unlike group 3 in relation to group 1. AH it indicates to us vitamin A anti-oxidant action, avoiding that the enzyme levels decreases. To...
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artículo
Se evaluó el efecto antioxidante de Lepidium meyenii walpers (Maca) en ratas albinas para observar su influencia sobre el desarrollo de la osteoporosis. Se utilizaron 25 ratas hembras albinas de 4 meses de edad, las que fueron divididas en 5 grupos, el primer grupo (Gl) considerado como control y 4 grupos experimentales (G2, G3, G4 Y GS) se les indujo osteoporosis aplicándose1es heparina 2Ulj g/ interdiariamente por un periodo de tres semanas, al mismo tiempo se efectuó la administración de antioxidantes (G3) y productos naturales (maca al G4 y soya al GS) siendo G2 el grupo control de osteoporosis. Al término de este periodo se tomó muestras de sangre y orina para los análisis de Cata lasa (CA T) Y Superóxido Dismutasa (SOD) para evaluar el efecto antioxidante e Hidroxiprolina urinaria y calcio como marcadores de la resorción ósea. El grupo G2 que presentó osteoporosis mostr...
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artículo
The current study is an evaluation of Vitamin A supplement diet in female white mice Balb C53 inoculated with Sarcoma 180. The oral administration of a dose of 200 IU per day of Vitamin A in mice inoculated with sarcoma and divided in two groups, obtained a greater group B (vitamin A supplemented diet) mice survival curve than group A (normal diet) mice survival curve; however more studies are necessary to get a statistical significance. Liver concentration of catalasa was also quantified in three groups of mice: (1) healthy mice with normal diet; (2) sarcoma inoculated mice with normal diet; an (3) sarcoma inoculated mice with vitamin A supplement díet. It showed a significant difference of concentration of catalasa in group 2 in relation to group 1, unlike group 3 in relation to group 1. AH it indicates to us vitamin A anti-oxidant action, avoiding that the enzyme levels decreases. To...
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artículo
Se sintetizó el estanato de cinc, Zn2SnO4 (ZTO) por el método hidrotérmico empleando una temperatura de 200 ºC durante 16 h. El material obtenido fue caracterizado por difracción de rayos X (DRX) y microscopia electrónica de transmisión (MET). El tamaño de cristalito calculado a partir de su difractograma fue de 40 nm. La actividad fotocatalítica del ZTO fue evaluada estudiando la degradación del colorante anaranjado de metilo en solución acuosa bajo iluminación luz ultravioleta. Los resultados muestran una degradación de aproximadamente 30% luego de 60 min de tratamiento.
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artículo
The purpose of this research is to evaluate the performance of production of alginic acid laboratory scale in order to compare the results of the kinds of brown algae: Lessonia trabeculata vs. Macrocystis pyrifera. The results indicate higher performance in the production of acid alginic from Macrocystis pyrifera regarding Lessonia trabeculata.
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objeto de conferencia
The authors acknowledge funding support from CONCYTEC-FONDECYT within the call E041-01 [contract number 015-2018-FONDECYT/BM]. H.E.H. acknowledges funding support from the Brazilian Agency CNPq under Projects No 465757/2014-6 (INCT FOTONICOM) and No 312714/2019-2 (HEH’s Research Productivity Grant)
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artículo
The authors would like to thank to FONDECYT-UK J008-2016 for the financial support during the course of this work.
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objeto de conferencia
The underrepresentation of women in IT related majors such as computer science, computer engineering, and information systems (IS) has been evident all over the world. As a result, many private and public institutions have created programs aimed to increase enrollment, recruitment, and placement of women in the field and reduce the gender gap in the field. Several journal publications about this kind of research can be found in the scientific literature about studies mostly conducted in the United States, Europe, Asia and Australia, but very few publications about this kind of research in Latin American countries is available in the literature despite the fact that in the last ten years, countries in Latin America also developed a variety of programs with the same goal with the support of international organizations like the United Nations Educational, Scientific and Cultural Organizatio...
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artículo
The physicochemical properties (antioxidant activity, total polyphenols and tannins contents) of tara extracts have been obtained. Samples were taken from the pod of tara (powder, fiber, seed coat and the inside of the seed) by maceration and Soxhlet extraction. All extracts have high antioxidant activity with an IC50 between 10 and 121 µg/mL. The total polyphenol content varies between 40 and 150 mg GAE/g of sample and the tannins content varies between 22 and 80%.
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artículo
Nanoparticles of zinc peroxide were synthesized by sol-gel technique using as precursors aqueous solutions of zinc acetate di-hydrate (Zn(CH3COO)2.2H2O) and hydrogen peroxide (H2O2) at 30%. During the synthesis the sol was exposed to an specific radiation (gamma or ultraviolet). The structure of the ZnO2 nanoparticles was characterized by X-ray diffraction. The sol absorbance vs. the time of irradiation was studied for UV irradiated sols. Thin films of ZnO2-ZnO were made using spray pyrolysis of the irradiated sols. The morphology of these films was studied by atomic force microscopy.
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artículo
Thirty four nose decorations from the tomb of the Lady of Cao has been analyzed by EDXRF-analysis and transmission measurements. These nose decorations are made partially on gold, and partially on silver. EDXRF-analysis showed that, while gold areas all show a similar composition, silver areas exhibit an erratic composition, and also an unusual high percentage of gold, up to 35 %. To verify that this erratic composition is not depending on surface enrichment processes, X-ray transmission measurements were carried out, which gives the bulk composition of the samples. These last measurements completely confirm EDXRF-results. Therefore the conclusion could be that a high quantity of gold was added intentionally to the silver alloys, for not clear reasons, may be to avoid the oxidation process typical of high concentration silver in silver alloys.
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artículo
In this work, we identify soil degradation by salinity, using images of HRG-2 (SPOT), TM and ETM+ (LANDSAT) of high spatial resolution in the sugarcane crops of Empresa Agroindustrial de Pomalca, located in the Lambayeque Region at the north coast of Peru. The reflectance of the surface soil, normalized difference vegetation index, NDVI, and salinity index, IndSal, was estimated from the satellite images using the image processing software ENVI 4.5, and the programming language IDL.Also, the maximum compound values of the NDVI and IndSal was determined from the TM and ETM+ images to identify soils with low farming quality and degraded soils by salinity. To estimate the salinity in the sugarcane farming, we performed, by graphics, the correlation between the soil electrical conductivity, CE, and the spectral reflectance values extracted from the B1, B2, B3 and B4 (TM-20/04/2008) bands ...
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artículo
Objetivos: Caracterizar la actividad académica, el cumplimiento de las obligaciones, programa, metodología, materiales, actitud del docente, evaluación, prácticas, satisfacción. Establecer las coincidencias y divergencias de la actividad educativa en Enfermería. Y comprometer a los involucrados a participar en el diseño de propuestas. Diseño: Método descriptivo, transversal, cuantitativo, complementado con técnicas cualitativas. Institución: Departamento Académico Profesional de Enfermería, Facultad de Medicina, UNMSM. Participantes: Estudiantes y docentes. Intervenciones: Se efectuó el estudio en 135 estudiantes y 27 docentes (30% del universo de docentes y estudiantes). La escala fue de 1 a 5, siendo 1 definitivamente negativa y 5 definitivamente positiva. Principales medidas de resultados: Calidad de la actividad académica. Resultados: En estudiantes fue 3,57 y en docen...