1,515 research outputs found
Conductivities from attractors
In the context of applications of the AdS/CFT correspondence to condensed
matter physics, we compute conductivities for field theory duals of dyonic
planar black holes in 3+1-dimensional Einstein-Maxwell-dilaton theories at zero
temperature. We combine the near-horizon data obtained via Sen's entropy
function formalism with known expressions for conductivities. In this way we
express the conductivities in terms of the extremal black hole charges. We
apply our approach to three different examples for dilaton theories for which
the background geometry is not known explicitly. For a constant scalar
potential, the thermoelectric conductivity explicitly scales as
, as expected. For the same model, our approach yields
a finite result for the heat conductivity even for
.Comment: 29 page
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IMPACT OF SCHOOL-BASED MENTAL HEALTH SERVICES ON STUDENT ATTENDANCE AT A SOUTHERN CALIFORNIA SCHOOL DISTRICT
When children experience trauma, it impacts their development, mental stability, learning, and behavior. This causes an increased need for prevention and early intervention mental health services within the public school system. Some California school districts offer mental health services students can utilize at their schools. Social workers are best equipped to assist and provide students with the necessary mental health resources due to their education, training, and role. This study used secondary data from 101 randomly selected Southern California school district participants. This study examined the relationship between children’s attendance, age, gender, primary diagnosis, living arrangements, number of traumatic events experienced, problems children have at school, family mental health history, and program completion. The findings will help school districts conceptualize the need for mental health services
Time dependence of entanglement for steady state formation in AdS/CFT
We consider a holographic model of two 1+1-dimensional heat baths at
different temperatures joined at time , such that a steady state
heat-current region forms and expands in space for times . After
commenting on the causal structure of the dual 2+1-dimensional spacetime, we
present how to calculate the time-dependent entanglement entropy of the
boundary system holographically. We observe that the increase rate of the
entanglement entropy satisfies certain bounds known from the literature on
entanglement tsunamis. Furthermore, we check the validity of several
non-trivial entanglement inequalities in this dynamic system.Comment: 6 pages, 6 figures, these proceedings summarize a talk given at the
Karl Schwarzschild Meeting 2017 and the much longer paper 1705.04696. v2:
reference adde
Time evolution of entanglement for holographic steady state formation
Within gauge/gravity duality, we consider the local quench-like time
evolution obtained by joining two 1+1-dimensional heat baths at different
temperatures at time t=0. A steady state forms and expands in space. For the
2+1-dimensional gravity dual, we find that the shockwaves expanding the
steady-state region are of spacelike nature in the bulk despite being null at
the boundary. However, they do not transport information. Moreover, by adapting
the time-dependent Hubeny-Rangamani-Takayanagi prescription, we holographically
calculate the entanglement entropy and also the mutual information for
different entangling regions. For general temperatures, we find that the
entanglement entropy increase rate satisfies the same bound as in the
"entanglement tsunami" setups. For small temperatures of the two baths, we
derive an analytical formula for the time dependence of the entanglement
entropy. This replaces the entanglement tsunami-like behaviour seen for high
temperatures. Finally, we check that strong subadditivity holds in this
time-dependent system, as well as further more general entanglement
inequalities for five or more regions recently derived for the static case.Comment: 57 pages, 25 figures. v2: Minor revisions and references added. v3:
Referee's comments included. The numerical codes described in this paper are
available in the ancillary files directory (anc/) of this submissio
The effect of extrusion and drying on roller techniques concerning the rheological characteristics of rice-, corn-, sweet potato-, bean- and cassava root- and leaf- based composite flour
Promoting food security in Latin-America and the Caribbean is directly related to agricultural products. The region faces a food crisis which has reduced large population groups’ access to food. This work contributes to the study of obtaining precooked composite flour made from biofortified crops using protein, vitamin A and/or minerals. This study evaluated the effect of precooked flour’s composition and precooking on its solubility in water, water absorption capacity, consistency and viscosity; such flour was obtained by extrusion and drying on rollers. The composite flours were obtained from cassava roots, sweet potato tubers, corn, rice and bean grains and cassava leaves. Four composite flours were formulated taking four- to six-year-old children’s daily nutrient requirements (protein, iron, zinc and beta-carotenes) as a basis. The extruder was operated at 90ºC, 300 rpm screw rotation speed, 17.64 g/min feed flow, with 30% moisture mixture. The dryer rollers were operated at 4 rpm roller rotation speed, 90ºC surface temperature and 1 mm separation between rollers. It was determined that flour dried on rollers led to more complete cooking and modified starch granule structure than precooking by extrusion, thereby producing flour having greater solubility in water, less water absorption, higher consistency and smaller viscosity, comparable to that of pattern flour.J. Aristizábal, A. Combariza, A. Fernández and M. Sánche
Insectos Asociados a Passiflora Longipes y Passiflora Bogotensis en un Fragmento de Bosque Alto Andino de la Sabana de Bogotá
Se determinaron los insectos asociados a dos especies de pasifloras silvestres Passiflora bogotensis y Passiflora longipes (Passifloraceae) en un fragmento de bosque alto andino de la Sabana de Bogotá. En P. bogotensis se registraron insectos fitófagos de los órdenes Diptera, Lepidoptera, Hemiptera y Coleoptera, enemigos naturales del órden Hymenoptera y polinizadores de los órdenes Hymenoptera y Diptera. En P. longipes se registraron insectos fitófagos de los órdenes Diptera y Coleoptera, y no se registraron enemigos naturales y polinizadores. P. bogotensis y P. longipes desde el bosque pueden estar prestando servicios ecosistémicos para la agricultura a través de la actividad de los insectos
Implementación de las buenas prácticas pecuarias para predios productores de leche con destino al consumo humano de la finca Berlín del municipio de Chiquinquirá- Boyacá
Las Buenas Prácticas Ganaderas (BPG) en la producción de leche son un conjunto de normas y procedimientos que buscan asegurar la calidad e inocuidad de la leche, así como el bienestar animal y la sostenibilidad ambiental y económica. Estas prácticas abarcan áreas como la sanidad animal, la higiene en el ordeño, la nutrición, la manipulación y el almacenamiento de la leche. Algunos aspectos clave de las BPG incluyen la limpieza y desinfección de equipos, la capacitación del personal en prácticas higiénicas, el control de la alimentación y el manejo adecuado de residuos. La implementación de las BPG contribuye a la obtención de leche saludable y de calidad, garantizando la seguridad alimentaria y el cumplimiento de las regulaciones específicas en cada país.Good Livestock Practices (GGP) in milk production are a set of standards and procedures that seek to ensure the quality and safety of milk, as well as animal welfare and environmental and economic sustainability. These practices cover areas such as animal health, milking hygiene, nutrition, milk handling and storage. Some key aspects of GMP include cleaning and disinfecting equipment, training staff in hygienic practices, food control, and proper waste management. The implementation of GMP contributes to obtaining healthy, quality milk, guaranteeing food safety and compliance with specifi c regulations in each country
Potencial Turístico en el Distrito De Chilca
El principal objetivo de esta investigación fue determinar cuál es el potencial
turístico del distrito de Chilca, el cual se realizó en un tiempo de 4 meses, en el año
2016.
La presente investigación fue de tipo cualitativa, no se trabajó con un tamaño de
población y muestra pre – establecida, el muestreo que se utilizo es el no -
probabilístico de máxima variación. Se realizó las entrevistas a 6 personas del
distrito de Chilca durante el presente año
La metodología del presente estudio se realizó mediante fuentes secundarias,
donde se recurrió a tesis y artículos científicos. Los datos obtenidos en este estudio
provienen de los resultados logrados por la aplicación de una observación de
campo y una entrevista de 11 preguntas.
Como conclusión se puede manifestar que el distrito de Chilca cuenta con potencial
turístico, pero falta desarrollarlo. Poniendo énfasis en el cuidado y mantenimiento
de los recursos turísticos con los que cuenta y desarrollar el buen trato y la calidad
de servicio que se brinda a los turistas, esto sería en cada uno de los proveedores
de los servicios turísticos. Además, se tuvo como recomendaciones realizar charlas
informativas sobre la actividad turística en el distrito, para que la población se
continúe involucrando en el desarrollo del mismo, implementar campañas de
concientización sobre el cuidado de los recursos turísticos y realizar mayor difusión
de los eventos que se realizan en el distrito para atraer mayor cantidad de turistas
y por parte de la municipalidad, fomentar el turismo en el distrito
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