909 research outputs found
Radio light curves during the passage of cloud G2 near Sgr A*
We calculate radio light curves produced by the bow shock that is likely to
form in front of the G2 cloud when it penetrates the accretion disk of Sgr A*.
The shock acceleration of the radio-emitting electrons is captured
self-consistently by means of first-principles particle-in-cell simulations. We
show that the radio luminosity is expected to reach maximum in early 2013,
roughly a month after the bow shock crosses the orbit pericenter. We estimate
the peak radio flux at 1.4 GHz to be 1.4 - 22 Jy depending on the assumed orbit
orientation and parameters. We show that the most promising frequencies for
radio observations are in the 0.1<nu<1 GHz range, for which the bow shock
emission will be much stronger than the intrinsic radio flux for all the models
considered.Comment: 15 pages, 10 figures, accepted for publication in MNRA
EVALUATION OF ANTI-ARTHRITIC POTENTIAL OF PARTITIONED EXTRACTS OF BOUGAINVILLEA X BUTTIANA (VAR. ROSE) HOLTTUM AND STANDL
Objective: Bougainvillea is a natural source with potential for clinical use, and this plant is routinely employed in traditional Medicine in Mexico. This study planned to evaluate the effect of ethanolic extract partitioned of Bougainvillea x buttiana on acute and chronic inflammation.Methods: The extract from Bougainvillea x buttiana partitioned originated two phases the aqueous (BxbREaq) and organic (BxbREop) phases were employed in anti-inflammatory activity. Acute inflammation was evaluated using the carrageenan model, whereas the chronic inflammation with anti-arthritic potential was explored with complete Freund´s adjuvant (CFA). Arthritis was caused by intradermal inoculation of CFA, and the extract was administered orally at different doses for 21 d. Paw oedema was determined at 7, 14 and 21 d, and serum from the mice were obtained to detect cytokine levels by ELISA and for biological assays.Results: Phytochemistry studies revealed that these extracts contain alkaloids, carbohydrates, fatty acids, and tannins. The results demonstrated that these extracts significantly inhibited mouse paw oedema for acute and chronic inflammation in a dose-dependent manner. Additionally, BxbREop extracts markedly inhibited the production of TNF-α, IL-1β, and IL-6 and remarkably increased IL-10 in serum from mice with control or arthritic groups.Conclusion: The combined results suggest that BxbREop extract shows a potent effect in mice against CFA-induced arthritis for its ability to inhibit paw oedema and arthritic symptoms
Dialogic Reading with Adolescent Mothers
The purpose of this study was to evaluate the effectiveness of teaching dialogic reading (DR) strategies to adolescent mothers as measured by DR strategy use during shared book reading with their children. The secondary purpose was to determine the impact of adolescent mothers\u27 implementation of DR strategies on their preschool children’s single word vocabulary. A single subject multiple baseline across behaviors research design was implemented with one adolescent mother and her twin boys. Based on visual analysis of graphical representation of the data, it was determined there was a moderate to strong functional relation between educating an adolescent mother on DR and her implementation of DR strategies during shared book reading, depending on the DR strategy. Receptive and expressive scores on the individual book assessments decreased from baseline to intervention. These results provide preliminary evidence that adolescent mothers have the potential to implement new strategies during shared book reading when provided with direct support. Future research with this population should strive towards developing an intervention for adolescent mothers and their children to enhance children’s language and literacy development
Manejo de los desechos solidos domiciliarios y hospitalarios [Houesehold and hospital waste management]
Se decidió analizar cuál es la situación actual en el manejo de los desechos, con el objetivo de determinar la variación en los índices de generación de los desechos domésticos y establecer cuál es la situación con respecto a algunos hospitales privados. La información servirá de insumo para el Proyecto "Estado de la Nación" del 2005, a través del cual se realiza un esfuerzo continuo para informar a la sociedad sobre aspectos relevantes para que, de esta manera, pueda entender su propia realidad y participar en las orientaciones y acciones futuras por realizar, pues la información es fundamental para el funcionamiento de la democracia. Para conocer la realidad se necesitan datos que ayuden en la construcción de indicadores que reflejen la compleja realidad nacional. Con el presente trabajo se presentan algunos indicadores para la generación de desechos domiciliarios correspondientes a algunas municipalidades de zonas urbanas y zonas rurales, así como los obtenidos para hospitales privados, comparados con datos disponibles de algunos hospitales públicos de la Caja Costarricense del Seguro Social
Metabolism of materials by the construction sector in developing countries : Costa Rica as a case study
Production practices require large amounts of materials and are not likely to be sustained without large implication for the environment. Materials and energy are put together in order to produce goods and the total of these physical processes have been referred by Ayres and Simons as "Industrial Metabolism", which was defined as "the whole integrated collection of physical processes that convert raw materials, plus labour, into finished products and wastes in a (more or less) steady-state condition". A good understanding of societal metabolism is likely to contribute to more sustainable production and consumption. The construction industry and its related materials, service, and supply feeder industries are jointly considered to be both the world's largest industrial employer and the largest natural resources consumer as well as a great waste producer. In developing countries, construction waste is becoming a serious environmental problem due to the continuing growing population and urbanization, which demand material resources, water and energy. Information and data about the sector in those economies is scarce and some of the information found can't be compared with other data. An assessment has been done in Costa Rica in order to understand how construction materials are metabolised (transformed) by the sector. The study provides an idea of the amount of waste generation and its composition. It also shows the causes, which are related to design, procurement, material handling, operation, residual and others
Cumplimiento de las recomendaciones de práctica de actividad física y percepción de barreras en estudiantes de bachillerato
El objetivo de este estudio fue conocer los niveles de actividad física (AF) así como la percepción de barreras para la realización de AF en estudiantes de Bachillerato, analizando dichas variables en función del género, curso académico, práctica deportiva extraescolar y tipo de jornada. Se realizó un estudio descriptivo transversal en el que participaron 248 adolescentes, 120 chicos y 128 chicas ( M = 15.32; DT = 1.81), 144 de 1º de Bachillerato y 104 de 2º de Bachillerato. Se utilizó el Cuestionario Internacional de AF en su versión corta (IPAQ-SF) y la Escala de Barreras para la práctica de AF . Los resultados señalaron que menos del 30% de los estudiantes de Bachillerato alcanza las recomendaciones de práctica de AF, siendo el grado de cumplimiento más elevado en los chicos (38.3%), en el alumnado de 1º de Bachillerato (30.6%), en el alumnado que realiza práctica deportiva extraescolar (36.7%) y entre semana (31%). Por otro lado, las barreras referentes al tiempo fueron superiores en el alumnado de 2º de Bachillerato, mientras que las barreras relativas al disfrute fueron superiores en las chicas y en el alumnado que no realizaba práctica deportiva extraescolar. Los resultados destacan la importancia de promover la práctica regular de AF en Bachillerato, especialmente en las chicas y en los adolescentes de 2º curso, a través de programas de intervención que ayuden a mejorar la gestión del tiempo de ocio y estimulen el desarrollo de los procesos motivacionales.
The aim of this study was to analyze physical activity (PA) levels and perceived barriers to PA in High School students. Similarly, differences in gender, academic year, out-of-school sport and type of day were analyzed among these variables. In this cross-sectional study, 248 adolescents, 120 boys and 128 girls (M = 15.32; SD = 1.81), were involved. The sample was made up of 144 12th grade students (58.1%) and 104 13th grade students. The International PA Questionnaire-Short Form (IPAQ-SF) and the Scale of Barriers to PA were used. The results showed that less than 30% of High School students comply with the PA guidelines, being higher in boys (38.3%), in the 12th High School students (30.6%), in the students who practiced extracurricular sports (36.7%) and weekdays (31%). On the other hand, barriers relating to time adolescents were higher in students of 13th High School, while barriers relate to enjoyment were higher in girls and students who did not practice extracurricular sports. The results highlight the importance of promoting PA in High School students, especially in girls and 12th High School, through intervention programs that help improve the management of their leisure time and development of motivational processes
Effect of Threonine and the Bioactive Component of Saccharomyces Cerevisiae on the Productive Performance of the Broiler Cobb 500
This study was conducted in Chimborazo province, Riobamba Canton to evaluate the effect of threonine and the bioactive component of Saccharomyces cerevisiae on the productive performance of the broiler Cobb 500. A total of 270 one-day-old broiler chicken of both sexes were included, which corresponded to an experimental unit size of 15 birds. Two growth promoters were used for the treatments -- T1: Threonine (aminoacid) 200 g/Tn; and T2: bioactive oligosaccharides, obtained from the cell wall of selected strains of S. Cerevisiae (probiotic) 750 g/Tn. These were compared to a control group. The data were analyzed through Analysis of Variance (ADEVA). The separation of means was performed using the Tukey statistic at a level of significance of p < 0.05 and p < 0.01. The data were processed using the Infostat software version 2010. The results showed that the best productive yields were with treatment 2; the values for this treatment were: weight at 28 days: 1369.42 g; weight gain at 28 days: 48.90 g; food conversion at 28 days: 1.39 points; carcass weight: 2527.05 g; and yield to the carcass: 83.85%. Through the economic analysis, it was determined that the highest cost-benefit index was 1.30 USD with the application of T2. So according to the results, a better use of the nutrients that are present in the feed is achieved when bioactive components of S. cerevisiae are supplied in the diet of broiler chickens.
Keywords: Threonine, Saccharomyces cerevisiae, productive performance, broiler, Cobb 500.
RESUMEN
Se realizó un experimento en la provincia de Chimborazo, Cantón Riobamba, para evaluar los efectos de treonina y componentes bioactivos de Saccharomyces cerevisiae sobre el comportamiento productivo en aves Cobb 500. Se utilizaron 270 pollitos mixtos Cobb 500 de un día de edad de ambos sexos, con un tamaño de unidad experimental de 15 aves. Para los tratamientos se manejaron dos promotores de crecimiento, T1: Treonina (aminoácido) 200 g/Tn y T2: Oligosacáridos bioactivos, obtenidos a partir de la pared celular de cepas seleccionadas de S. Cerevisiae750 g/Tn; frente a un testigo (T0). Los datos obtenidos fueron sometidos a Análisis de Varianza (ADEVA); la separación de medias se realizó mediante el estadístico Tukey a un nivel de significancia (p < 0,05) y (p < 0,01); los datos se procesaron mediante el software Infostat versión 2010. Los resultados muestran los mejores rendimientos productivos con el Tratamiento 2, para los parámetros: peso a los 28 días 1369,42 g; ganancia de peso a los 28 días 48,90 g; y conversión alimenticia a los 28 días con 1,39 puntos; así como peso a la canal 2527,05 g; y rendimiento a la canal 83,85%. Mediante el análisis económico se determinó que el mayor índice beneficio costo fue de 1,30 USD con la aplicación del T2. Lo que brinda un indicativo que mediante el suministro de componentes bioactivos de S. cerevisiae en la dieta de pollos broiler, se logra un mejor aprovechamiento de los nutrientes que se encuentran presentes en el alimento, lo que se refleja en los parámetros productivos.
Palabras clave: treonina, Saccharomyces cerevisiae, comportamiento productivo, broilers, Cobb 500
Complete Genome Sequence of the Alfalfa Symbiont Sinorhizobium/ Ensifer meliloti Strain GR4
We present the complete nucleotide sequence of the multipartite genome of Sinorhizobium/Ensifer meliloti GR4, a predominant
rhizobial strain in an agricultural field site. The genome (total size, 7.14 Mb) consists of five replicons: one chromosome, two
expected symbiotic megaplasmids (pRmeGR4c and pRmeGR4d), and two accessory plasmids (pRmeGR4a and pRmeGR4b).This work was supported by research grants BIO2011-24401 from the
Spanish Ministerio de Ciencia e Innovación and CSD 2009-0006 of Programme
Consolider-Ingenio, both including ERDF (European Regional
Development Funds).
L.M.-R. and J.A.L.-C. were supported by predoctoral fellowships
(Programs JAE-Predoc and I3P from Consejo Superior de Investigaciones
Científicas, respectively). We are particularly grateful to M. G. Claros and
R. Bautista from Plataforma Andaluza de Bioinformática (Universidad de
Málaga) Spain, to A. J. Fernández-González for bioinformatics support,
and to the Estación Experimental del Zaidín—CSIC for DNA sequencing
services.Peer reviewe
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