Low-level accretion in neutron-star X-ray binaries

We search the literature for reports on the spectral properties of neutron-star low-mass X-ray binaries when they have accretion luminosities between 1E34 and 1E36 ergs/s. We found that in this luminosity range the photon index (obtained from fitting a simple absorbed power-law in the 0.5-10 keV range) increases with decreasing 0.5-10 keV X-ray luminosity (i.e., the spectrum softens). Such behaviour has been reported before for individual sources, but here we demonstrate that very likely most (if not all) neutron-star systems behave in a similar manner and possibly even follow a universal relation. When comparing the neutron-star systems with black-hole systems, it is clear that most black-hole binaries have significantly harder spectra at luminosities of 1E34 - 1E35 erg/s. Despite a limited number of data points, there are indications that these spectral differences also extend to the 1E35 - 1E36 erg/s range. This observed difference between the neutron-star binaries and black-hole ones suggests that the spectral properties (between 0.5-10 keV) at 1E34 - 1E35 erg/s can be used to tentatively determine the nature of the accretor in unclassified X-ray binaries. We discuss our results in the context of properties of the accretion flow at low luminosities and we suggest that the observed spectral differences likely arise from the neutron-star surface becoming dominantly visible in the X-ray spectra. We also suggest that both the thermal component and the non-thermal component might be caused by low-level accretion onto the neutron-star surface for luminosities below a few times 1E34 erg/s.Comment: Accepted for publication in MNRA

Project-Based Learning for English Learners: Promises and Challenges

In this article the authors explore project-based learning (PBL) as an avenue for meeting the needs of English learners against the backdrop of both the 2010 California Common Core State Standards and the 2012 English Language Development Standards. They begin with a definition and brief history of PBL. The authors then propose and expanded version of PBL that considers the unique linguistic needs of ELs and conclude with two promising examples from two California school districts.https://digitalcommons.lmu.edu/ceel_journalarticles/1005/thumbnail.jp

English Learner Master Plan Playbook: Developing Equitable Local Policies for Multilingual and English Learners Students

The education of English Learners (ELs) is informed by federal, state, and local policies, research and practice. The EL Master Plan is the Local Education Agency’s (LEA) policy document that has the potential to positively impact the educational programs, practices and experiences of ELs. Aligned and informed by California’s English Learner Roadmap policy as well as federal requirements, this playbook is a guide for educational partners to use to achieve four goals in their LEAs EL Master Plans: (1) equitable, coherent, and sustainable systems; (2) equity-driven processes to deliver research-based programs and practices; (3) effective family-community engagement; and (4) accountability models that ensure EL students’ success. The authors include a variety of tools and processes for LEA’s to use in the development of their EL Master Plan.https://digitalcommons.lmu.edu/ceelreports/1007/thumbnail.jp

Touristic Virtual Environment of Tunguragua Province

Tourism and the advances that technology has had over the years have turned into useful instruments that are used to develop platforms and virtual touristic environments that can help in its management and positioning promotion-wise. The objective is to design a virtual touristic environment that will promote service providers, cultural activities, routes and touristic attractions that are found in the province of Tungurahua, and which include natural resources and historical sites that have not been exploited yet. The virtual environment’s goal is to integrate relevant information for tourists in the area, plus destinations and locations using a map, geolocation and georeferencing functions. The goal is to increase the flow of national and foreign visitors by using audiovisual archives or files. The validation of the goals was based on studies about the characteristics and the behavior of the tourists and information obtained from national public companies that are primarily related to tourism

M2-M5 blackfold funnels

We analyze the basic M2-M5 intersection in the supergravity regime using the blackfold approach. This approach allows us to recover the 1/4-BPS self-dual string soliton solution of Howe, Lambert and West as a three-funnel solution of an effective fivebrane worldvolume theory in a new regime, the regime of a large number of M2 and M5 branes. In addition, it allows us to discuss finite temperature effects for non-extremal self-dual string soliton solutions and wormhole solutions interpolating between stacks of M5 and anti-M5 branes. The purpose of this paper is to exhibit these solutions and their basic properties.Comment: 19 pages, 5 figures, harvmac; typo corrected in equation (3.19

Propiedades elásticas de películas de barniz

La flexibilidad no es una característica constante del film de pintura desde que esa propiedad se halla afectada por factores externos tales como humedad, temperatura y velocidad de elongación. De allí que resulte necesario acondicionar las probetas de ensayo entre límites de humedad y temperatura establecidos, antes de su ejecución y además controlar la velocidad de elongación. En los métodos que usan mandriles resulta más difícil mantener una velocidad de elongación determinada que cuando se realizan ensayos de tracción sobre películas libres. Es de esperar entonces que ensayos ejecutados a diferentes velocidades arrojen resultados distintos para un mismo material. Los otros factores, humedad y temperatura, son más fáciles de controlar. Las propiedades elásticas están íntimamente relacionadas con la composición del material. Se pretende en este trabajo estudiaren escala de laboratorio los parámetros de formulación que influyen en la elasticidad de películas orgánicas y a su vez efectuar las mediciones con diferentes técnicas y tratar de establecer correlación con los resultados de ensayos de exposición en servicio. Se han elaborado en el laboratorio muestras de barnices, sobre la base de cuatro resinas gliceroftálicas, cuya diferente composición se indica en la tabla I. A dichas resinas se les incorporó resina fenólica pura no reactiva de manera de obtener muestras con 0, 10, 20 y 30 por ciento de resina fenólica. Teóricamente estas muestras deberían tener diferente elasticidad

A los M. RR. PP. Mtros. Priores, Presidentes y á las RR. MM. Prioras, Presidentas y demas religiosos y religiosas de la Orden de Predicadores de nuestra provincia de Maria Sma. de Candelaria en Canarias. Nos Fr. Francisco de Armas ... Al tiempo mismo que aguardabamos ... la convocatoria para la celebracion de nuestro Capitulo General ..

Tít. tomado del principio del textoTexto fechado en " ... La Laguna ... á 30 de noviembre de 1831

Modelos predictivos de la distribución preferencial de larvas de peces demersales en la parte sur de la corriente de California

Habitat characterization provides predictive information about the distribution of species and is useful for as­sessing habitat quality and population stability. Larval abundance of six frequent and abundant demersal species and the relationship of each with the environment were analysed through generalized additive models to determine their preferential distribution and predictive response to the environmental variables in the southern part of the California Current (25-31°N) between two periods of data collection: 1997-2000 and 2006-2010. Essentially, the main associated variables governing the distribution patterns were related to common and oceanographic characteristics of the water column (temperature and salinity at 50 m depth, dynamic height and degree of water column stratification); however, the set of variables and their ranges are usually species-specific. Species of northern distribution, Sebastes sp. and Citharichtys stigmaeus, were recorded mainly in newly emerged, relatively unstratified waters characterized by a shallow mixed layer and low temperatures. Low dynamic height values were the most significant predictor of larval distribution for Merluccius productus. Citharichthys xanthostigma and Symphurus atricaudus were widespread, distributed across the study area mainly in autumn in unstratified or stratified waters and at a shallow mixed layer. Particularly C. Xanthostigma and S. Lucioceps were related to high dynamic height val­ues, likely influenced by a coastal flow towards the pole, as evidenced by counter-currents.La caracterización del hábitat proporciona información predictiva sobre la distribución de las especies y es útil para evaluar la calidad del hábitat y estabilidad de la población. La abundancia larval de seis especies demersales frecuentes y abundantes y de su relación con el medio ambiente se analizaron a través de modelos aditivos generalizados (GAM) para determinar su distribución preferencial y respuesta a las variables ambientales en la parte sur de la corriente de California (25-31°N) entre dos periodos de datos recolectados 1997-2000 y 2006-2010. Esencialmente, las principales variables aso­ciadas que rigen los patrones de distribución fueron en términos de las variables comunes y oceanográficas de la columna de agua (temperatura y salinidad a 50 m de profundidad, altura dinámica y grado de estratificación de la columna de agua), sin embargo, el conjunto de variables y los rangos suelen ser específicos de la especie. Especies con distribución norteña, Sebas­tes sp. y Citharichtys stigmaeus, se registraron principalmente en aguas de surgencia, identificadas por aguas relativamente no estratificadas, poca profundidad de capa mixta y menor temperatura; y menor altura dinámica, como el predictor más significativo de la distribución de larvas de Merluccius productus. Citharichthys xanthostigma y Symphurus atricaudus se distribuyeron ampliamente a lo largo del área de estudio preferentemente en otoño, en aguas no estratificadas o estratificadas y baja profundidad de la capa de mezcla, pero particularmente C. Xanthostigma y S. Lucioceps en valores altos de alturas dinámicas probablemente influenciadas por el flujo costero hacia el polo indicado por las contracorrientes

Entropy of the self-dual string soliton

We compute the entropy and the corresponding central charge of the self-dual string soliton in the supergravity regime using the blackfold description of the fully localized M2-M5 intersection.Comment: 15 pages, 1 figure, harvma

Importance of tissue sampling, laboratory methods, and patient characteristics for detection of Pneumocystis in autopsied lungs of non-immunosuppressed individuals

To understand the epidemiological significance of Pneumocystis detection in a lung tissue sample of non-immunosuppressed individuals, we examined sampling procedures, laboratory methodology, and patient characteristics of autopsy series reported in the literature. Number of tissue specimens, DNA-extraction procedures, age and underlying diagnosis highly influence yield and are critical to understand yield differences of Pneumocystis among reports of pulmonary colonization in immunocompetent individuals.publishersversionpublishe