656 research outputs found
The compact group--fossil group connection: observations of a massive compact group at z=0.22
It has been suggested that fossil groups could be the cannibalized remains of
compact groups, that lost energy through tidal friction. However, in the nearby
universe, compact groups which are close to the merging phase and display a
wealth of interacting features (such as HCG 31 and HCG 79) have very low
velocity dispersions and poor neighborhoods, unlike the massive, cluster-like
fossil groups studied to date. In fact, known z=0 compact groups are very
seldom embedded in massive enough structures which may have resembled the
intergalactic medium of fossil groups. In this paper we study the dynamical
properties of CG6, a massive compact group at z=0.220 that has several
properties in common with known fossil groups. We report on new g' and i'
imaging and multi-slit spectroscopic performed with GMOS on Gemini South. The
system has 20 members, within a radius of 1 h_70^-1 Mpc, a velocity dispersion
of 700 km/s and has a mass of 1.8 x 10^14 h_70^-1 Msun, similar to that of the
most massive fossil groups known. The merging of the four central galaxies in
this group would form a galaxy with magnitude M_r' ~ -23.4, typical for
first-ranked galaxies of fossil groups. Although nearby compact groups with
similar properties to CG 6 are rare, we speculate that such systems occurred
more frequently in the past and they may have been the precursors of fossil
groups.Comment: 7 pages, 3 figures (one color, low resolution), uses emulateapj.sty.
Accepted for publication in ApJ Lette
The role of nitrogen sources and caffeine for growth of Pleurotus ostreatus (oyster mushroom)
The use of spent coffee grounds (SCG) for cultivation of Pleurotus ostreatus has become a popular way to reuse this type of waste. However, it is unclear if high mushroom yields can be achieved or if the caffeine content of residues can be substantially decreased for safe disposal of SCG. To address this lack of knowledge, this study provides key information related to the fate of caffeine during cultivation of P. ostreatus on SCG. Using agar and in liquid culture, a wide range of nitrogen sources (including caffeine) and extracts from fresh and spent coffee grounds were evaluated for their ability to support vegetative (mycelial) growth. It was found that inorganic N was the best source for mycelial growth and that caffeine, while toxic at high concentrations, also promoted growth at low concentrations. Pleurotus ostreatus was also grown on SCG-amended substrates to evaluate the effect of caffeine during both vegetative and reproductive phases. In two trials, P. ostreatus was grown in treatments ranging from pure SCG (SCG100) through to pure sawdust (sawdust100) and with intermediary mixtures of these substrates. In a laboratory-scale study, three of the four treatments became fully colonized (SCG100, SCG25+sawdust75 and SCG50+sawdust50) but only SCG100 and SCG25+sawdust75 developed mushrooms. Caffeine degradation by P. ostreatus occurred when grown on SCG (with and without sawdust) with caffeine and its degradation products detected in both the substrate and fruiting bodies. In a commercial-scale study, full colonization was observed for SCG25+sawdust75 and sawdust100 and mushrooms developed on both. Again, caffeine degradation was detected and there was a decrease in caffeine content of the SCG. All of the compounds that have been previously described for fungal degradation of caffeine were detected, identified and a likely degradation pathway was suggested
4-H as a culturally responsive program : building an afterschool 4-H program that engages Latino youth and parents in Sacramento, CA
In a richly diverse state -- and one where no single ethnic group makes a clear majority -- the University of California 4-H Youth Development Program (CA 4-H YDP) is proposing new program structures to attract and serve Latino audiences, especially through a 4-H Club experience. One such structure creates 4-H Clubs in established after-school programs that take place on school sites. The 4-H Youth Development Program in Sacramento, California, has a history of engaging African American, Asian, and Latino youth in a variety of non-club programs, and is seeking to establish an after-school 4-H Club at a charter school serving primarily Latino children. In an effort to better understand the qualities that best support Latino participation inpositive youth development (PYD) programs, CA 4-H YDP also commissioned a review to synthesize the research and literature in this area. The resulting paper (Erbstein and Fabionar, 2014) explores Latino participation in PYD programs through a framework, Positive Youth Development Program Elements, which includes four components: conceptual framework, program elements, organizational infrastructure, and organizational and community relationships. This paper has two purposes: to describe the process, challenges, and outcomes in forming a predominately Latino 4-H Club in an after school setting; and to view the process of forming the Club through the lens of the Positive Youth Development Program Elements framework
Gemini Frontier Fields: Wide-field Adaptive Optics -band Imaging of the Galaxy Clusters MACS J0416.1-2403 and Abell 2744
We have observed two of the six Frontier Fields galaxy clusters, MACS
J0416.1-2403 and Abell 2744, using the Gemini Multi-Conjugate Adaptive Optics
System (GeMS) and the Gemini South Adaptive Optics Imager (GSAOI). With
0.08"-0.10" FWHM our data are nearly diffraction-limited over a 100"x100" wide
area. GeMS/GSAOI complements the Hubble Space Telescope (HST) redwards of
1.6microns with twice the angular resolution. We reach a 5 sigma depth of Ks =
25.6 mag (AB) for compact sources. In this paper we describe the observations,
the data processing and the initial public data release. We provide fully
calibrated, co-added images matching the native GSAOI pixel scale as well as
the larger plate scales of the HST release, adding to the legacy value of the
Frontier Fields. Our work demonstrates that even for fields at high galactic
latitude, where natural guide stars are rare, current multi-conjugated adaptive
optics technology at 8m-telescopes has opened a new window on the distant
Universe. Observations of a third Frontier Field, Abell 370, are planned.Comment: Accepted for publication in ApJS; significantly revised compared to
the first submissio
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Integrating Genetics and the Plasma Proteome to Predict the Risk of Type 2 Diabetes.
La cultura del proyecto
Desde las connotaciones del diseño y situados en el ámbito académico miramos el hacer arquitectónico basados en la presentación visual de las obras arquitectura. En este sentido, proponemos un diálogo con los procedimientos de aproximación hasta la figura del proyecto de arquitectura
Relación entre los subdominios de la función ejecutiva y balance postural: implicancias en el riesgo de caídas en el adulto mayor autovalente residente en la comunidad
Tesis (Magíster en Neurorehabilitación)En Chile, la población mayor de sesenta años ha aumentado considerablemente y se estima que, aproximadamente un tercio de la población que reside en la comunidad sufrirá una caída en el transcurso de un año. Considerando que la evaluación del efecto de la cognición en pruebas clínicas de balance postural podría mejorar la identificación de adultos mayores de la comunidad en riesgo de sufrir caídas, se requiere analizar la relación entre la función ejecutiva y el balance postural en esta población. Pese a que diversos estudios respaldan la relación entre función ejecutiva y balance postural en el adulto mayor, existe escasa evidencia sobre cuál subdominio de la función ejecutiva está más relacionado con el balance postural e implícitamente con el riesgo de caídas.
El propósito de esta investigación fue determinar la relación entre los subdominios de la función ejecutiva (inhibición, cambio mental, actualización y monitoreo) y balance postural y su implicancia en el riesgo de caídas en adultos mayores autovalentes residentes en la comunidad.
La investigación se llevó a cabo con una muestra de cincuenta sujetos adultos mayores pertenecientes al programa Más Adulto Mayor Autovalente, de Hualpén, que cumplieron con los criterios de inclusión y exclusión del estudio. Se obtuvo información demográfica y se realizaron pruebas estandarizadas específicas para los tres subdominios de la función ejecutiva (para inhibición- Stroop Colour Word Test de interferencia; para cambio mental- Trail Making Test, parte B; para actualización y monitoreo- test de Retención de Dígitos en orden inverso) y el balance postural a través del Mini-BESTest.
La correlación entre los resultados de la prueba Trail Making Test parte B (TMT-B) y el Mini-BESTest es negativa, con un rango de relación entre moderada y fuerte (rho= -0,539; p= 0,00). De igual manera, la correlación entre los resultados de la prueba Stroop Colour Word Test de interferencia y el Mini-BESTest es negativa, con un rango de relación débil (rho= -0,395; p= 0,05). Por otra parte, la correlación entre los resultados del test Retención de Dígitos en orden inverso (DOI) y el Mini-BESTest es positiva, con un rango de relación débil (rho= 0,349; p= 0,013).
La presente investigación, ha demostrado que el balance postural se correlaciona con los tres subdominios de la función ejecutiva (cambio mental, inhibición y actualización y monitoreo). De los tres subdominios de la función ejecutiva, el cambio mental medido a través del Trail Making Test parte B, presentó un grado de relación lineal entre fuerte y moderado con el balance postural, medido a través del Mini-BESTest. Por último, nuestros resultados sugieren que la función ejecutiva debe ser investigada más a fondo, para determinar la magnitud de su efecto sobre el balance postural en adultos mayores residentes en la comunidad
Inmigración, infancia e integración socioeducativa: un estudio etnográfico sobre niños palestinos en Chile
A great problem of the immigration is the social and educational integration of thechildren in his colleges. This ethnographic study, analyzes the social and school interactionsin a primary school with refugee Palestinian students. The aim is to know the processesof integration and the implicit conceptions in these processes. The results show that thecuriosity of the beginning into the relations between students turns in stereotypes topromote the acculturation as institutional practice. In the interaction student - school,exist labels towards the students, who are perceived as low. In the relations betweenparents and school, the stereotype demonstrates the cultural differences. Nevertheless,some out-of-school practices exist with characteristics of cultural miscegenation.Una de las problemáticas que implica la inmigración es la integración social y educativade los niños en sus colegios. A través de un estudio etnográfico, se lleva a cabo un análisis delas interacciones socieducativas al interior de una escuela básica que acoge a estudiantesque son refugiados palestinos, con el fin de conocer los procesos de integración y lasconcepciones implícitas a la base de estos procesos. Los resultados muestran que en lasrelaciones entre pares, la curiosidad inicial derivó en estigmatizaciones mediatizadaspor la promoción de la aculturación como práctica institucional. En la interacciónestudiante-escuela, existen rotulaciones hacia los estudiantes, quienes son vistos comoinferiores. En el nivel de relaciones entre apoderados y escuela, la estigmatización semantiene, quedando en evidencia el papel de las diferencias culturales. Sin embargo,en este nivel existen prácticas extraescolares con características de mestizaje cultural
Análisis de las diferentes interpretaciones jurisprudenciales al parágrafo del Art. 57 de la Ley 1453 de 24 junio de 2011
Con este trabajo investigativo buscamos Identificar, analizar y describir las diferentes tesis Jurisprudenciales que se han planteado sobre la rebaja de pena en situaciones de captura en Flagrancia, con la reforma introducida por la ley 1453 de 2011 en su artículo 57, cuestionándola desde el punto de vista de su diseño legislativo, su imprecisión y susceptibilidad de diversas interpretaciones que conducen a la indeterminación de la pena, vulnerando el artículo 29 de la Constitución Nacional, teniendo en cuenta el ultimo pronunciamiento de la Corte Constitucional donde se dio vía libre a los Jueces para que apliquen la posición que más se ajuste a sus convicciones
Use of Peroxyacetic Acid as Green Chemical on Yield and Sensorial Quality in Watercress (Nasturtium officinale R. Br.) Under Soilless Culture
The goal of this research was to evaluate the effect of different doses of peroxyacetic acid on the productivity of watercress (Nasturtium officinale R. Br.) cultivated hydroponically using a constant nutritive solution. Green chemistry in protected horticulture seeks compatibility with the environment through the creation of biodegradable byproducts. In hydroponics, appropriate doses of peroxyacetic mixtures deliver these byproducts while also oxygenating the roots. Watercress producers who recirculate the nutritive solution can use these mixtures in order to increase oxygenation in the hydroponic system. The experiment took place between August and December 2009, beginning with the planting of the watercress seeds and concluding with the completion of the sensory panels. A completely random design was used, including three treatments and four repetitions, with applications of 0, 20 and 40 mg L−1 of the peroxyacetic mixture. Measured variables were growth (plant height, leaf length and stem diameter), yield (weight per plant and dry matter) and organoleptic quality (color and sensory panel). The application of 40 mg L−1 of the peroxyacetic mixture had a greater effect on the growth and development of the plants, which reached an average height of 29.3 cm, stem diameter of 3.3 mm and leaf length of 7.6 cm, whereas the control group reached an average height of only 20.2 cm, stem diameter of 1.9 mm and leaf length of 5.7 cm. The application of the peroxyacetic mixtures resulted in an improvement in growth parameters as well as in yield. Individual weights achieved using the 40 mg L−1 dose were 1.3 g plant−1 in the control group and 3.4 g plant−1 in the experimental group (62% yield increase). Sensory analysis revealed no differences in organoleptic quality
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