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Search Results: 1 - 10 of 59445 matches for " Lourdes Vargas y Vargas "
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Identification and Quantification of Monosaccharides in Aloe vera Gel by Acid and Enzymatic Hydrolysis and Wet Heat Treatment  [PDF]
Dianeli Madera Pi?a, Carlos Hernán Herrera Méndez, Lourdes Vargas y Vargas, Herbert Loria Sunza, Jorge Tamayo Cortez
Food and Nutrition Sciences (FNS) , 2017, DOI: 10.4236/fns.2017.88060
Abstract: Aloe vera (Aloe barbadensis Miller) possesses curative and therapeutic properties attributed to the polysaccharides found in its tissue. This work aimed to study hydrolyzed (chemical and enzymatical) Aloe vera gel extracts using ultrafiltration membranes with a pore size of 0.22 micron (μm). Nine chemical treatments were achieved with H2SO4 and three wet heat treatments were carried out at a pressure of 1.2 lbf/in2 for 15 minutes; in both cases, three different concentrations of Aloe vera gel juice (AGJ) were used: 1.5%, 2.5% and 3.5% w/w. The concentrations of H2SO4 were 0.10%, 0.25% and 0.40% w/w. Chemical experiments are performed over a factorial 32 design and results were analyzed using SPSS software (version 17, SPSS Inc.), finding the one labeled T7 (15 ml of AGJ 3.5% with 15 ml of H2SO4 0.10% added) the best of them, as it leaded to 0.0446 mg/ml of liberated glucose. Among the three wet heat treatments, the one labeled TC3 (15 ml of AGJ 3.5% with 15 ml of H2O added) was the best-performing one, as it leaded to 0.292 mg/ml of liberated glucose. Furthermore, an enzymatic hydrolysis was carried out using Novozymes’ Pectinex? AR and Viscozyme?. Hydrolisis with both enzymes yield to better results than acid hydrolysis: in the treatment with Pectinex? AR, 3.282 mg/ml of liberated glucose were obtained and 3.302 mg/ml in the treatment with Viscozyme?. The hydrolyzed substances obtained by acid and enzymatic hydrolysis, as well as by wet heat treatment, were subsequently analyzed by thin layer chromatography (TLC), using glucose, galactose and arabinose 1000 ppm solutions as reference patterns. Among the treatments by H2SO4, the one labeled T4 obtained an Rf value of 50, the same as on the galactose reference pattern.
Purification and Partial Characterization of Polyphenol Oxidase from Sapodilla Plum (Achras sapota)  [PDF]
Jorge Tamayo Cortez, Carlos Hernán Herrera Méndez, Enrique Sauri Duch, María de Lourdes Vargas y Vargas, Sara Solís Pereira
Food and Nutrition Sciences (FNS) , 2013, DOI: 10.4236/fns.2013.47093
Abstract: The browning of fruits can be considered as an enzymatic oxidation which is believed to be one of the main causes of quality loss during post-harvest handling. The enzymes responsible for this are the oxidoreductases; the polyphenol oxidase (PPO) (monophenol, o-diphenol, oxygen oxidoreductase; EC belongs to this group. This enzyme, which is found in the sapodilla plum (Achras sapota), was purified using a phenylsepharose and a SephacrylS-200 columns. The molecular weight of the purified enzyme was estimated to be about 66 kDa by gel filtration and 29 kDa by SDS-PAGE. A single protein band was found using the latter system (SDS-PAGE), which shows that the PPO of the pulp of the sapodilla plum may be composed of two protein subunits with similar molecular weight. The optimum pH was 7.0 and the optimum temperature 60. The most effective inhibitors tested were ascorbic acid, sodium metabisulfite and acetic acid.
Main Polysaccharides Isolated and Quantified of Aloe vera Gel in Different Seasons of the Year  [PDF]
Berenice Aranda Cuevas, Carlos Hernán Herrera Méndez, Ignacio Islas Flores, Sara Solís-Pereira, Luis Cuevas-Glory, Gerardo Rivera Mu?oz, María de Lourdes Vargas y Vargas, Jorge Tamayo Cortez
Food and Nutrition Sciences (FNS) , 2016, DOI: 10.4236/fns.2016.76046
Abstract: We developed and implemented a methodology that allowed extracting and evaluating high molecular weight polysaccharides present in the gel of Aloe barbadensis Miller. One of the fractions evaluated revealed the presence of high molecular weight carbohydrates (200 kDa) with a behavior similar to that of acemannan and another fraction with compounds of molecular weights between 17 and 47 kDa. We quantified the concentration of acemannan for two different growing periods. The concentration of acemannan in the high molecular weight fraction was 99.97 ppm in the rainy season and 106.03 ppm in the dry season. The concentration of acemannan in the fraction of low molecular weight was 9.364 ppm during the season of greatest rainfall and 26.939 ppm in the dry season.
Santos y Vargas,Leonides;
Acta bioethica , 2002, DOI: 10.4067/S1726-569X2002000100011
Abstract: this text proposes a number of reflections that issue fron the recent advancements that have taken place in investigations on the human genoma project, which lead to the accelerated reinforcement of biomedical knowledge and technologies. the new statements upon human species’ biological nature, legitimated by these new progress, allow us to reexamine the mythological and metaphysical explanations accumulated for millenia, facing a new philosophical anthropology. the advancements of medical science’s interventions upon health and quality of life, allow us to evaluate again the legitimateness of a quantity of new biomedical possibilities. this text touches, too, in a particular way, the subject of cloning and it’s different economic and political aspects
Leonides Santos y Vargas
Acta Bioethica , 2002,
Abstract: Este texto propone una serie de reflexiones que se desprenden de los recientes progresos acaecidos en las investigaciones sobre el Proyecto del Genoma Humano, los cuales conducen al fortalecimiento acelerado de conocimientos y tecnologías biomédicas. Las nuevas afirmaciones sobre la naturaleza biológica de la especie humana, legitimadas por estos nuevos progresos, posibilitan reexaminar explicaciones mitológicas y metafísicas acumuladas desde hace milenios, en el contexto de una nueva antropología filosófica. Los progresos en las intervenciones de la ciencia médica sobre la salud y la calidad de la vida humana permiten evaluar nuevamente la legitimidad de una serie de nuevas posibilidades biomédicas. Es así como este texto aborda también, de manera particular, la temática de la clonación y de sus distintos aspectos económicos y políticos Este texto prop e reflex es sobre os recentes progressos apresentados pelas investiga es decorrentes do Projeto Genoma Humano que conduzem a sólidos conhecimentos em tecnologias biomedicas. As novas informa es sobre a natureza da espécie humana obtidas por esses avan os permitem reexaminar explica es mitológicas e metafísicas acumuladas por milênios através da ótica da antropologia filosófica. Os progressos nas interven es da ciência sobre a saúde e qualidade de vida humana permitem avaliar a legitimidade de uma série de proposi es biomédicas. Nesse sentido, o presente texto apresenta reflex es sobre o tema da clonagem e seus diferentes aspectos econ micos e políticos This text proposes a number of reflections that issue fron the recent advancements that have taken place in investigations on the Human Genoma Project, which lead to the accelerated reinforcement of biomedical knowledge and technologies. The new statements upon human species’ biological nature, legitimated by these new progress, allow us to reexamine the mythological and metaphysical explanations accumulated for millenia, facing a new philosophical anthropology. The advancements of medical science’s interventions upon health and quality of life, allow us to evaluate again the legitimateness of a quantity of new biomedical possibilities. This text touches, too, in a particular way, the subject of cloning and it’s different economic and political aspects
María de Lourdes Vargas Gardu?o
Didasc@lia : Didáctica y Educación , 2010,
Abstract: This work lies in a project untitled: “Analysis of the teaching-trainee and the generation of the formative process in bilingual schools, from the production of argumentative texts”. Here, it is pretended to elaborate a strategy to support the teachers’ formation. The dealing of this problem allows us to check the educative processes from the interculturality; to identify the meaning people provide to the learning a different language from their mother tongue, especially when the mother tongue is an aborigine one: thep’urhepecha (spoken in Meseta region, in Michoacán) and the second language: Spanish. In this work, the supports of the philosophy of the culture are developed, which allow understanding better the phenomenon studied.
Dise o y producción de un material didáctico hipermedia
Laura Regil Vargas,Lourdes de Quevedo Orozco
Reencuentro , 2005,
Abstract: Este artículo presenta algunas reflexiones teóricas sobre la experiencia en el dise o, producción y uso de un material didáctico hipermedia, en soporte CD-ROM, Mirar para saber, producido por la Universidad Pedagógica Nacional (UPN). En el marco del análisis de la relación entre universidades y medios electrónicos de comunicación, la travesía, aquí expuesta, se hace con el objetivo de compartir los pormenores en el desarrollo de un software educativo universitario orientado a la apreciación estética, visto desde aspectos fundamentales como: interactividad, estructura y el uso estratégico de los lenguajes multimedia (audio, imagen, animación, texto e hipertexto).
Symptomatic changes in postmenopause with different methods of hormonal therapy  [PDF]
Marcelino Hernández-Valencia, Nydia Cordova, Antonio Vargas, Lourdes Basurto, Renata Saucedo, Carlos Vargas, Miriam Ruiz, Leticia Manuel-Apolinar, Arturo Zárate
Open Journal of Preventive Medicine (OJPM) , 2011, DOI: 10.4236/ojpm.2011.12004
Abstract: Objective: The diversity of opinions on the adverse effects of medications used to treat postmenopausal symptoms has prompted the use of various routes and mechanisms of action that need to be explored because bioavailability of the medications can vary. In order to select the appropriate route of administration for hormonal therapy (HT), it is necessary to determine baseline therapeutic efficacy. Design: We designed a prospective, randomized study consisting of four groups of postmenopausal wo-men: group 1 received oral conjugated estrogens, group 2 received a synthethic steroid, group 3 received estradiol nasally in spray form, and group 4 used transdermal estradiol in the form of patches. Criteria used to evaluate effectiveness was the Greene scale, which evaluate six components. These criteria were applied to each patient before hormonal intervention and then each month for 6 months. Luteinizing hormone (LH), follicle stimulating horone (FSH) and estradiol concentration were determined by chemiluminescence. Student’s t-test was used for intra-group comparisons before and after treatment. Results: There was a significant decrease in the vasomotor and sexual component (p < 0.05) with the use of four HT types. For depression, a difference was observed with synthetic steroids and oral estrogens. Upon analyzing the somatic component there was a decrease in symptoms with nasal and transdermal routes. Psychological changes were observed with the use of oral synthethic steroids and transdermal patches. Anxiety component demonstrated differences with nasal spray and oral estrogens, although all HT forms in this component showed a pattern of irregular changes. Conclusions: Changes in the response could be due each route of administration and medication used. Absorption variability may exist, which has repercussions in the control of symptoms and should be taken into consideration when selecting the appropriate route of administration for patients beginning HT.
Perfil da demanda em um servi?o de Oftalmologia de aten??o primária
Vargas, Márcia Abelin;Rodrigues, Maria de Lourdes Veronese;
Revista Brasileira de Oftalmologia , 2010, DOI: 10.1590/S0034-72802010000200002
Abstract: purpose: to improve health services it is necessary to know the demand profile. this study was carried out with the objectives of: to identify the main reasons to seek an ophthalmologic primary care service; and to analyze the frequency of the principal diagnoses, according to gender and age groups, as well as the causes of referring patients. methods: retrospective and descriptive study of 1,010 assisted patients during a period of 6 months. parameters: age and sex of the patient, the reason of the visit, diagnosis (icd-10) and frequency of referral. the data were obtained through the analysis of the medical records and data-recording sheets with the icd-10 registration. some patients (male and female) presented with different morphological and structural alterations, and were allocated in more than one diagnostic group. results: there was a predominance of females (61.5%) in the age group from 10 to 19 years of age (16.7%) followed by the group of patients between 40 and 49 years of age (16.5%). the main reason for the consultation was a low visual acuity (37.4%), followed by the review of glasses (19.0%).there were also frequent complaints of headache (15.8%), pruritus (10.4%), burning / irritation (7.8%) and red eye (7.2%). among abnormal tests the largest prevalence was of refractive errors (70.0%) and presbyopia (31.9%). ninety patients (8.9%) were referred, mainly for surgical treatment. conclusion: the main reason of the search of an ophthalmology basic service was low visual acuity that in great majority of times was caused by refractive errors and / or presbyopia. few were the cases which were not resolved at the service place.
Consideraciones para una evaluación docente en la Universidad de Costa Rica
Vargas Porras, Alicia,Calderón Laguna, María Lourdes
Revista Electrónica Actualidades Investigativas en Educación , 2005,
Abstract: En este artículo se presentan los resultados de un proyecto de investigación realizado en el 2002- 2003 por Alicia E. Vargas, Carolina Bola os, José Miguel Gutiérrez, Lorena Kikut, María Lourdes Calderón y Miguel ángel González, docentes investigadores del Centro de Evaluación Académica de la Universidad de Costa Rica. El objetivo principal fue identificar características del profesorado universitario y de su trabajo, como insumos para mejorar la evaluación docente que se realiza en esta Universidad. La investigación se centró en construir un concepto de docencia, en términos de las competencias y desempe os que se consideran como excelentes. Para ello, además de la obligada revisión bibliográfica sobre el tema, se llevó a cabo un estudio, mediante talleres y encuestas, para construir el concepto de docente excelente, según lo plantea el mismo profesorado, el alumnado y las directivas universitarias. En una segunda etapa del estudio, se abordó el tema de las especificidades didácticas, según tipos de curso, mediante consulta a la comunidad docente y talleres con amplia participación. Los resultados obtenidos en esta investigación aportan una conceptualización de lo que significa ser docente en la UCR y, así mismo, se logra diferenciar los requerimientos del desempe o docente, según tipo de curso. La información generada aporta criterios para la construcción de evaluaciones docentes en el ámbito universitario. This article presents the results of a research carried out during the period 2002-2003 by Alicia E. Vargas, Carolina Bola os, José Miguel Gutiérrez, Lorena Kikut, María Lourdes Calderón and Miguel ángel González, researches of the Centre for Academic Evaluation of the University of Costa Rica. Its main objective was to identify teaching qualities in higher education as inputs for the improvement of the evaluation of teachers that is carried out at the University of Costa Rica. The study aimed, in the first place, to clarify the concept of an excellent teacher in terms of competencies and expected production at this university. In that respect, besides a thorough review of literature, workshops were carried out and questionnaires were applied in order to clarify the main aspects considered by teachers, students and university authorities in that respect. In a second stage of the study and with a wide participation of the university community, there was a clarification of the main didactic specialities that teachers must have, according to the different course modalities that they may use. The generated information obtained in this research contribu
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