Horizon Feedback Inflation

We consider the effect of the Gibbons-Hawking radiation on the inflaton in the situation where it is coupled to a large number of spectator fields. We argue that this will lead to two important effects - a thermal contribution to the potential and a gradual change in parameters in the Lagrangian which results from thermodynamic and energy conservation arguments. We present a scenario of hilltop inflation where the field starts trapped at the origin before slowly experiencing a phase transition during which the field extremely slowly moves towards its zero temperature expectation value. We show that it is possible to obtain enough e-folds of expansion as well as the correct spectrum of perturbations without hugely fine-tuned parameters in the potential (albeit with many spectator fields). We also comment on how initial conditions for inflation can arise naturally in this situation.Comment: v1: 17 pages, 5 figures. v2: updated discussion and references, removed typos, submitted to journal. v3: minor revisions, version published in EPJ

Análisis tecnico-economico del uso de las diferentes tecnicas de cañoneo en los campos operados por petro produccion

El presente trabajo es un Análisis Técnico - Económico del uso de las diferentes técnicas de cañoneo en los campos operados por Petroproducción. La importancia de que la operación de cañoneo resulte más eficiente radica básicamente en las penetraciones alcanzadas y por ende en las razones de productividades estimadas a partir de estas, sin dejar de tomar en cuenta el daño total generado por las diferentes técnicas de estudio. Para realizar un adecuado análisis de los diferentes sistemas de cañoneo, este trabajo muestra fundamentos teóricos y técnicos, selección de pozos y análisis económicos; encasillados en seis capítulos

Save to Win: Using Contests to Promote Savings

We ask whether linking savings accounts to contests can promote saving. We do this by offering contest-linked accounts to individuals in rural Uganda where poverty is a serious problem. Our design builds off of results in experimental economics documenting excessive competitiveness in contests, with the goal of harnessing this behavior for the good. We find that, properly designed, we encourage savings beyond both pre-treatment levels and the control group. We explore reasonable heterogeneous treatment effects and document long lasting impacts on wealth

Adquisición y visualización de vídeo 3D

La visualización de imágenes en 3D es posible gracias a los sistemas estereoscópicos, que nos permiten capturar diferentes vistas de una misma escena y mediante el procesado de estas se consigue extraer información de profundidad que nos permite realizar el efecto. El sistema estereoscópico está formado por dos cámaras convencionales situadas a una distancia de unos 65mm con el fin de simular la vista humana. El objetivo de este proyecto es realizar un sistema estereoscópico y procesar las imágenes obtenidas por este sistema, para finalmente lograr el efecto 3D. Esto lo logramos por medio de un proceso de calibración mediante los parámetros intrínsecos (internos de la cámara) y extrínsecos (informan de la rotación y traslación de los ejes de referencia de las cámaras respecto a los de la escena), conseguidos a través de imágenes controladas. Este proceso es conocido como rectificación del par estéreo y consiste en alinear los puntos de las dos vistas de modo que consigamos tener una correspondencia entre las dos vistas y la escena. Una vez calibrado el sistema estereoscópico se procesan las imágenes para visualizarlas en diferentes modos: anaglífico (método de visualización directa) y Side by Side (método que requiere de procesado y dispositivos necesarios para visualizar mediante la técnica de secuencia de frames alternados). Por tanto, se obtienen diferentes modos de visualización para su posterior transmisión, objetivo de otros TFC. El sistema estereoscópico es la fase inicial de un sistema completo de transmisión de imágenes, el cual dará el flujo de entrada con las posibilidades anteriormente expuestas. El sistema completo está compuesto por las siguientes fases: adquisición, codificación, transmisión, decodificación y visualización de imágenes en tres dimensiones

Targeting exertional breathlessness to improve physical activity:the role of primary care

Primary care physicians (PCPs) play a crucial role in the diagnosis and management of chronic obstructive pulmonary disease (COPD). By working together with patients to target exertional breathlessness and increase physical activity, PCPs have an important role to play, early in the disease course, in improving patient outcomes in both the short and long term. In this article, we consider how physical activity affects disease progression from the PCP perspective. We discuss the role of pharmacological therapy, the importance of an holistic approach and the role of PCPs in assessing and promoting physical activity. The complexity and heterogeneity of COPD make it a challenging disease to treat. Patients’ avoidance of activity, and subsequent decline in capacity to perform it, further impacts the management of the disease. Improving patient tolerance of physical activity, increasing participation in daily activities and helping patients to remain active are clear goals of COPD management. These may require an holistic approach to management, including pulmonary rehabilitation and psychological programmes in parallel with bronchodilation therapy, in order to address both physiological and behavioural factors. PCPs have an important role to optimise therapy, set goals and communicate the importance of maintaining physical activity to their patients. In addition, optimal treatment that addresses activity-related breathlessness can help prevent the downward spiral of inactivity and get patients moving again, to improve their overall health and long-term prognosis

Chandra Observations of Eight Sources Discovered by INTEGRAL

We report on 0.3-10 keV observations with the Chandra X-ray Observatory of eight hard X-ray sources discovered within 8 degrees of the Galactic plane by the INTEGRAL satellite. The short (5 ks) Chandra observations of the IGR source fields have yielded very likely identifications of X-ray counterparts for three of the IGR sources: IGR J14091-6108, IGR J18088-2741, and IGR J18381-0924. The first two have very hard spectra in the Chandra band that can be described by a power-law with photon indices of Gamma = 0.6+/-0.4 and -0.7(+0.4)(-0.3), respectively (90% confidence errors are given), and both have a unique near-IR counterpart consistent with the Chandra position. IGR J14091-6108 also displays a strong iron line and a relatively low X-ray luminosity, and we argue that the most likely source type is a Cataclysmic Variable (CV), although we do not completely rule out the possibility of a High Mass X-ray Binary. IGR J18088-2741 has an optical counterpart with a previously measured 6.84 hr periodicity, which may be the binary orbital period. We also detect five cycles of a possible 800-950 s period in the Chandra light curve, which may be the compact object spin period. We suggest that IGR J18088-2741 is also most likely a CV. For IGR J18381-0924, the spectrum is intrinsically softer with Gamma = 1.5(+0.5)(-0.4), and it is moderately absorbed, nH = (4+/-1)e22 cm-2. There are two near-IR sources consistent with the Chandra position, and they are both classified as galaxies, making it likely that IGR J18381-0924 is an Active Galactic Nucleus (AGN). For the other five IGR sources, we provide lists of nearby Chandra sources, which may be used along with further observations to identify the correct counterparts, and we discuss the implications of the low inferred Chandra count rates for these five sources.Comment: Accepted by ApJ, 14 page

Producción y comercialización de las hortalizas COL (Brassica Oleracea L. Vr Acephala D.C.) Cilantro (Corriandrum Sativum L.) Cebolla De Rama (Miura Fistulosum L.) en el municipio de Santa Marta.

La investigación se efectuó en distinto Centro de producción. La información primaria se obtuvo mediante encuestas hecha personalmente a los agricultores de hortalizas "Col (Brassica Oleracea L. Vr Acephala D.C.) Cilantro (Corriandrum Sativum L.) Cebolla de rama (Allium fis 52 y la información secundaria con personas y entidades vinculadas con el cultivo. Los objetivos básicos del estudio fueron un diagnóstico de producción y comercializacion de estas hortalizas

GEMINI near-infrared spectroscopic observations of young massive stars embedded in molecular clouds

K-band spectra of young stellar candidates in four southern hemisphere clusters have been obtained with the near-infrared spectrograph GNIRS in Gemini South. The clusters are associated with IRAS sources that have colours characteristic of ultracompact HII regions. Spectral types were obtained by comparison of the observed spectra with those of a NIR library; the results include the spectral classification of nine massive stars and seven objects confirmed as background late-type stars. Two of the studied sources have K-band spectra compatible with those characteristic of very hot stars, as inferred from the presence of Civ, Niii, and Nv emission lines at 2.078 micron, 2.116 micron, and 2.100 micron respectively. One of them, I16177 IRS1, has a K-band spectrum similar to that of Cyg OB2 7, an O3If* supergiant star. The nebular K-band spectrum of the associated UC Hii region shows the s-process [Kriii] and [Seiv] high excitation emission lines, previously identified only in planetary nebula. One young stellar object (YSO) was found in each cluster, associated with either the main IRAS source or a nearby resolved MSX component, confirming the results obtained from previous NIR photometric surveys. The distances to the stars were derived from their spectral types and previously determined JHK magnitudes; they agree well with the values obtained from the kinematic method, except in the case of IRAS15408-5356, for which the spectroscopic distance is about a factor two smaller than the kinematic value.Comment: This is the version that will be published by the Montly Notices of the Royal Astronomical Societ