1,501 research outputs found
Quasi-Exact Solvability and the direct approach to invariant subspaces
We propose a more direct approach to constructing differential operators that
preserve polynomial subspaces than the one based on considering elements of the
enveloping algebra of sl(2). This approach is used here to construct new
exactly solvable and quasi-exactly solvable quantum Hamiltonians on the line
which are not Lie-algebraic. It is also applied to generate potentials with
multiple algebraic sectors. We discuss two illustrative examples of these two
applications: an interesting generalization of the Lam\'e potential which
posses four algebraic sectors, and a quasi-exactly solvable deformation of the
Morse potential which is not Lie-algebraic.Comment: 17 pages, 3 figure
Resignificaci?n del concepto de evaluaci?n formativa como eje dinamizador de la labor de los docentes en la Instituci?n Educativa ?Luis Carlos Gal?n Sarmiento? de Honda
236 p. Recurso Electr?nicoEl presente trabajo de investigaci?n tuvo como objetivo diagnosticar las pr?cticas de
evaluaci?n de los aprendizajes desarrolladas en la instituci?n educativa Luis Carlos
Gal?n Sarmiento del municipio de Honda-Tolima, con el fin de proponer estrategias que
fortalezcan la reflexi?n y la conceptualizaci?n para trasformar la evaluaci?n a partir de
seis categor?as: Conceptos de evaluaci?n educativa y evaluaci?n de los aprendizajes,
t?cnicas e instrumentos, usos, finalidades y principios. As? mismo se realiza un proceso
de formaci?n a trav?s del plan Lector a partir de algunos referentes te?ricos con el fin
de resignificar la evaluaci?n de los aprendizajes y mejorar los procesos evaluativos en
la instituci?n educativa, se realizaron intervenciones al SIE y al plan de clase.
El enfoque de la investigaci?n fue de tipo cualitativa, alcance descriptivo y dise?o
Investigaci?n Acci?n Participaci?n, el cual permiti? transformar las pr?cticas de
evaluaci?n de 23 docentes y de esta forma hacer un aporte a la comunidad acad?mica
y a la comunidad educativa de la regi?n en torno al tema de la evaluaci?n que es tan
importante en el proceso de ense?anza y aprendizaje y a la vez complejo.
Palabras claves: Evaluaci?n formativa, Sistema de Evaluaci?n SIE, Plan lectorThis research had as objective to diagnose learning assessment practices developed in
the educational institution Luis Carlos Gal?n Sarmiento in Honda - Tolima town in
order to propose strategies that strengthen reflection and conceptualization to transform
evaluation based on six categories: Concepts of educational evaluation and evaluation
of learning, techniques and instruments, uses, purposes and principles. Likewise, a
training process is carried out through the reader plan based on some theoretical
references in order to resignify the evaluation of learning and improve the evaluation
processes in the educational institution, interventions were made to the SIE and the
class plan.
The focus of the research was qualitative, descriptive and design Research Action
Participation, which allowed to transform the evaluation practices of 23 teachers and in
this way make a contribution to the academic community and the educational
community of the region about evaluation that is so important and at the same time
complex in the teaching and learning process.
Keywords: Formative evaluation, Evaluation System SIE, Reader Pla
ASSESMENT OF ANTI-INFLAMMATORY ACTIVITY AND CYTOTOXICITY OF FREEZE DRIED HYDROALCOHOLIC EXTRACT OF Bidens andicola ON ISOLATED NEUTROPHILS
Objective: The aim of this study was to evaluate anti-inflammatory activity and cytotoxicity in vitro of hydroalcoholic extract of Bidens andicola.Methods: B. andicola hydroalcoholic extract was obtained from aerial parts of B. andicola, following a standardized methodology. Briefly, aerial parts of B. andicola were extracted with ethanol 70% v/v and defatted with n-hexane, hydroalcoholic fraction was concentrated under controlled conditions in a rotary evaporator, and finally the residue was freeze-drying to obtain the hydroalcoholic extract of B. andicola. Anti-inflammatory activity and cytotoxicity assays were carried out using in vitro isolated neutrophils model using stable water-soluble tetrazolium salts.Results and Conclusions: The in vitro anti-inflammatory assay on isolated neutrophils demonstrated that the hydroalcoholic extract showed antiinflammatoryactivity compared to aspirin, with inflammatory inhibition percent values of 80.138±0.729 to hydroalcoholic extract of B. andicola and 82.117±0.762 to aspirin, each tested in five replicates at the concentration of 200 ppm of hydroalcoholic extract or reference.Â
Noncommutative effective theory of vortices in a complex scalar field
We derive a noncommutative theory description for vortex configurations in a
complex field in 2+1 dimensions. We interpret the Magnus force in terms of the
noncommutativity, and obtain some results for the quantum dynamics of the
system of vortices in that context
Fortaleciendo los h?bitos lectores implementando la literatura infantil como estrategia l?dico pedag?gica para enriquecer las habilidades comunicativas de los ni?os y ni?as del grado preescolar
116 p. Recurso Electr?nicoEl presente proyecto de investigaci?n centra su acci?n en estimular desde edades
tempranas, la lectura y el acercamiento a los libros, como v?a para desarrollar h?bitos
lectores y enriquecer las habilidades comunicativas.
Tiene como objetivo fijar en el ni?o el h?bito de la lectura donde el principal factor es
determinar aquellas posibles causas que propician o desmotivan a los ni?os el deseo de
leer dentro de su mundo, aprender a tener un h?bito lector a temprana edad se ve como
una necesidad en el desarrollo personal y social de cada uno de los ni?os, por eso vemos
necesidad o alternativa de desarrollar estrategias l?dico pedag?gicas como la literatura
infantil, por medio de un proyecto pedag?gico de aula para fortalecer h?bitos lectores,
que le permitan transformar su inteligencia creadora, mejorar sus competencias
comunicativas entre las que aparecen, leer, escribir, hablar y escuchar adem?s permite
acercarlos de manera agradable a los textos.
Conforme con esto, se tiene como referencia la investigaci?n formativa, de igual manera
un modelo de investigaci?n cualitativo con enfoque etnogr?fico, con ?nfasis participativo
y cooperativo, utilizando instrumentos como entrevistas, cuestionarios entre otros dentro
del desarrollo del proyecto. El cual se llev? mediante dos fases, la primera se hizo
mediante la observaci?n de la cual se detect? una problem?tica y la segunda en la cual
se hizo una intervenci?n mediante el proyecto pedag?gico de aula, que dio paso a la
participaci?n activa de toda una comunidad educativa.
Palabras clave: literatura ? lectura ? h?bitos ? cuentos ? habilidades comunicativasThe present research project focuses on stimulating reading and the approaching to
books from early ages, as a way to develop reading habits and enriching communicative
skills.
Its aim is to establish the habit of reading in children, where the main factor is to determine
those possible causes that encourage or discourage children the desire to read within
their world; learning to acquire a reading habit at an early age is seen as a necessity in
the personal and social development of each child, thus, it is seen the necessity or
alternative to implement dynamic-pedagogical strategies such as children's literature,
through a pedagogical classroom project to strengthen reading habits, that allows him to
transform his creative intelligence and to improve his communicative competences such
as, reading, writing, speaking and listening; it also allows to connect them in a pleasant
way to texts.
Accordingly, the research is based on formative research, as well as a qualitative
research model with an ethnographic approach, with a participative and cooperative
emphasis, using instruments such as interviews, questionnaires and others within the
project development. This was carried out in two phases: the first one was done through
the observation in which a problematic was detected and the second one, where an
intervention was made through the classroom pedagogical project, which gave way to the
active participation of an entire educational community.
Keywords: Literature - reading - habits - stories - communicative skill
The rapidly pulsating sdO star, SDSS J160043.6+074802.9
A spectroscopic analysis of SDSS J160043.6+074802.9, a binary system
containing a pulsating subdwarf-O (sdO) star with a late-type companion, yields
Teff = 70 000 +/- 5000 K and log g = 5.25 +/- 0.30, together with a most likely
type of K3V for the secondary star. We compare our results with atmospheric
parameters derived by Fontaine et al. (2008) and in the context of existing
evolution models for sdO stars. New and more extensive photometry is also
presented which recovers most, but not all, frequencies found in an earlier
paper. It therefore seems probable that some pulsation modes have variable
amplitudes. A non-adiabatic pulsation analysis of uniform metallicity sdO
models show those having log g > 5.3 to be more likely to be unstable and
capable of driving pulsation in the observed frequency range.Comment: 14 pages, 12 figures, accepted for publication in MNRAS, 2009
September
Identification of new putative driver mutations and predictors of disease evolution in chronic lymphocytic leukemia
Impact of footwear and foot deformities in patients with Parkinson?s disease: A case-series study
Background: Parkinson's disease (PD) is a common and complex neurological problem. Gait abnormalities are frequent in PD patients, and this increases the risk of falls. However, little is known about foot deformities and footwear in this vulnerable population. Here we investigate whether patients with PD use an appropriate shoe size and know if they have foot deformities or alterations. Methodology: A study of a series of observational descriptive cases in a convenience sample (n = 53 patients) diagnosed with Parkinson's disease. One trained investigator evaluated foot and ankle health. The footwear and foot measurements were obtained using a Brannock device. Results: The podiatric examination and footwear examination detected a high presence of podiatric pathologies and inappropriate footwear. This has a negative impact on the quality of life of these patients. Conclusions: This research detected an elevated number of people with foot deformities or alterations. Moreover, a high proportion of participants with PD wear inadequate footwear (in length, width, or both)
Biologically active Phytophthora mating hormone prepared by catalytic asymmetric total synthesis
A Phytophthora mating hormone with an array of 1,5-stereogenic centers has been synthesized by using our recently developed methodology of catalytic enantioselective conjugate addition of Grignard reagents. We applied this methodology in a diastereo- and enantioselective iterative route and obtained two of the 16 possible stereoisomers of Phytophthora hormone α1. These synthetic stereoisomers induced the formation of sexual spores (oospores) in A2 mating type strains of three heterothallic Phytophthora species, P. infestans, P. capsici, and P. nicotianae but not in A1 mating type strains. The response was concentration-dependent, and the oospores were viable. These results demonstrate that the biological activity of the synthetic hormone resembles that of the natural hormone α1. Mating hormones are essential components in the sexual life cycle of a variety of organisms. For plant pathogens like Phytophthora, sexual reproduction is important as a source of genetic variation. Moreover, the thick-walled oospores are the most durable propagules that can survive harsh environmental conditions. Sexual reproduction can thus greatly affect disease epidemics. The availability of synthetic compounds mimicking the activity of Phytophthora mating hormone will be instrumental for further unravelling sexual reproduction in this important group of plant pathogens.
Does Lithium Deserve a Place in the Treatment Against COVID-19? A Preliminary Observational Study in Six Patients, Case Report
Lithium has shown the capacity to: a) inhibit the replication of several types of viruses, some of which are similar to the SARS-CoV-2 virus, b) increase the immune response by reducing lymphopenia, and c) reduce inflammation by preventing or reducing the cytokine storm. In the present study, we have treated six patients with severe COVID-19 infection with lithium carbonate. We found that lithium carbonate significantly reduced plasma reactive C-Protein levels, increased lymphocyte numbers and decreased the neutrophil-lymphocyte ratio, improving both inflammatory activity and the immune response in these patients. We propose that lithium carbonate may deserve a place in the treatment against COVID-19
- …