7,008 research outputs found
Palomar\/Las Campanas Imaging Atlas of Blue Compact Dwarf galaxies: I. Images and integrated photometry
We present B, R, and Halpha images for a total of 114 nearby galaxies (v_helio-21mag), peak surface brightness (mu_B,peak<22mag/arcsec^2), and color at the peak surface brightness (mu_B,peak-mu_R,peak<~1). Halpha emission is detected in all but three sample galaxies. Typical color, absolute magnitude, and Halpha luminosity are (B-R)=0.7+/-0.3mag, M_B=-16.1+/-1.4mag, and log(L_Halpha)=40.0+/-0.6(erg/s). Galaxies morphologically classified as nE and iE BCDs within our sample show lower Halpha equivalent widths and redder colors, on average, than the iI and i0-type BCDs. For most of the galaxies the presence of an evolved stellar population is required to explain their observed properties; only the most metal-poor BCDs (e.g. IZw18, Tol65) are still compatible with a pure, young burst. The flux-calibrated and WCS-compliant images in this Atlas are individually available through the NASA/IPAC Extragalactic Database (NED) image server and collectively through a dedicated web page at http://nedwww.ipac.caltech.edu/level5/Sept02/Palco_BCD/frames.htm
Lactoferrin Decreases the Intestinal Inflammation Triggered by a Soybean Meal-Based Diet in Zebrafish
Indexación: Web of ScienceIntestinal inflammation is a harmful condition in fish that can be triggered by the ingestion of soybean meal. Due to the positive costs-benefits ratio of including soybean meal in farmed fish diets, identifying additives with intestinal anti-inflammatory effects could contribute to solving the issues caused by this plant protein. This study evaluated the effect of incorporating lactoferrin (LF) into a soybean meal-based diet on intestinal inflammation in zebrafish. Larvae were fed with diets containing 50% soybean meal (50SBM) or 50SBM supplemented with LF to 0.5, 1, 1.5 g/kg (50SBM+LF0.5; 50SBM+LF1.0; 50SBM+LF1.5). The 50SBM+LF1.5 diet was the most efficient and larvae had a reduced number of neutrophils in the intestine compared with 50SBM larvae and an indistinguishable number compared with control larvae. Likewise, the transcription of genes involved in neutrophil migration and intestinal mucosal barrier functions (mmp9, muc2.2, and beta-def-1) were increased in 50SBM larvae but were normally expressed in 50SBM+LF1.5 larvae. To determine the influence of intestinal inflammation on the general immune response, larvae were challenged with Edwardsiella tarda. Larvae with intestinal inflammation had increased mortality rate compared to control larvae. Importantly, 50SBM+LF1.5 larvae had a mortality rate lower than control larvae. These results demonstrate that LF displays a dual effect in zebrafish, acting as an intestinal anti-inflammatory agent and improving performance against bacterial infection.http://www.hindawi.com/journals/jir/2016/1639720
A Method for Modeling Decoherence on a Quantum Information Processor
We develop and implement a method for modeling decoherence processes on an
N-dimensional quantum system that requires only an -dimensional quantum
environment and random classical fields. This model offers the advantage that
it may be implemented on small quantum information processors in order to
explore the intermediate regime between semiclassical and fully quantum models.
We consider in particular system-environment couplings which
induce coherence (phase) damping, though the model is directly extendable to
other coupling Hamiltonians. Effective, irreversible phase-damping of the
system is obtained by applying an additional stochastic Hamiltonian on the
environment alone, periodically redressing it and thereby irreversibliy
randomizing the system phase information that has leaked into the environment
as a result of the coupling. This model is exactly solvable in the case of
phase-damping, and we use this solution to describe the model's behavior in
some limiting cases. In the limit of small stochastic phase kicks the system's
coherence decays exponentially at a rate which increases linearly with the kick
frequency. In the case of strong kicks we observe an effective decoupling of
the system from the environment. We present a detailed implementation of the
method on an nuclear magnetic resonance quantum information processor.Comment: 12 pages, 9 figure
Survival of quantum effects for observables after decoherence
When a quantum nonlinear system is linearly coupled to an infinite bath of
harmonic oscillators, quantum coherence of the system is lost on a decoherence
time-scale . Nevertheless, quantum effects for observables may still
survive environment-induced decoherence, and be observed for times much larger
than the decoherence time-scale. In particular, we show that the Ehrenfest
time, which characterizes a departure of quantum dynamics for observables from
the corresponding classical dynamics, can be observed for a quasi-classical
nonlinear oscillator for times . We discuss this observation in
relation to recent experiments on quantum nonlinear systems in the
quasi-classical region of parameters.Comment: submitted to PR
Management Models in SMEs, Strategic Tool in Business Management
The business sector constitutes an engine for the Ecuadorian economy through the generation of employment and redistribution of wealth. Therefore, given the current economic dynamics of high competition, globalization of markets, and use of information and communication technologies, business managers need to use different tools such as management models to achieve acceptable levels of utility, profitability, customer satisfaction and permanence in the consumer market. This research involved an analysis of the impact on corporate management of applying different management models of Small and Medium Enterprises (SMEs) in the city of Riobamba, province of Chimborazo (Ecuador). The study was descriptive, cross-sectional, exploratory and non-experimental and it was conducted in the first half of 2019. Data were collected through field investigation and the application of a structured survey with a sample composed of 136 managers, owners and administrators, from a population of 440 entrepreneurs. The results showed that 93% of entrepreneurs knew about the existence of management models, and 41% recorded that total quality is the most applied model followed by continuous improvement (18%) and re-engineering (13%). We conclude that entrepreneurs consider management models to be crucial in the management of their company.
Keywords: management model, business management, strategies, competitiveness, SMEs.
Resumen
El sector empresarial en todos sus niveles constituye un motor para la economía ecuatoriana, por la generación de empleo y redistribución de la riqueza; por ello los gerentes de las empresas dada la actual dinámica económica por la alta competencia, globalización de los mercados, uso de las tecnologías de información y comunicación, entre otras variables, necesita utilizar diferentes herramientas como son los modelos gerenciales para lograr niveles aceptables de utilidad, rentabilidad, satisfacción de los clientes y permanencia en el mercado consumidor. La investigación tiene como objetivo efectuar un análisis de la aplicación e incidencia en la gestión corporativa, de diferentes modelos gerenciales de las Pequeñas y Medianas empresas (Pymes) de la ciudad de Riobamba, provincia de Chimborazo (Ecuador). El estudio es descriptivo, transversal, exploratorio y no experimental efectuado en el primer semestre del año 2019, realizado mediante una investigación de campo, a través de la aplicación de una encuesta estructurada, seleccionando una muestra compuesta por 136 gerentes, propietarios y administradores, de una población de 440 empresarios. Los resultados obtenidos evidenciaron que el 93% de los empresarios conocen de la existencia de modelos gerenciales, el 41% registra que la calidad total es el modelo más aplicado seguido del mejoramiento continuo (18%) y Reingeniería (13%). Se concluye que los empresarios y emprendedores consideran a los modelos gerenciales de mucha importancia en la dirección de su empresa.
Palabras clave: modelo gerencial, gestión empresarial, estrategias, competitividad, pymes
Forage Quality Evaluation of Chopped Elephantgrass Hay through Intake and Digestibility Trial
The research was carried out to evaluate forage quality of chopped elephantgrass (Pennisetum purpureum Schum.) hay and to define a proper stage for cutting and haymaking of this grass. Chemical composition, voluntary intake, and apparent digestibility of the hays were studied at five different growth stages (30, 48, 63, 76, and 91 days). Twenty-five common wethers were utilized in a completely randomized experimental design. Dry matter (DM) voluntary intake was not different (P\u3e 0.05) from 30 to 63 days of regrowth and from 63 to 91 days and comprised 3.9; 3.5; 3.2; 2.1; and 2.4% of animal liveweight, respectively from 30 to 91 days. Digestibility coefficients of DM; OM; CP; EE; NDF; and ADF decreased linearly (P\u3c 0.001) as plant aged. At the experimental conditions haymaking of chopped elephantgrass showed good potential as a forage storage practice, particularly for low-input familial agricultural systems. According to DM yield, chemical composition, voluntary intake and apparent digestibility, the best grass cutting stage for haymaking occurred between 30 and 63 days
3D sensors for the HL-LHC
In order to increase its discovery potential, the Large Hadron Collider (LHC)
accelerator will be upgraded in the next decade. The high luminosity LHC
(HL-LHC) period demands new sensor technologies to cope with increasing
radiation fluences and particle rates. The ATLAS experiment will replace the
entire inner tracking detector with a completely new silicon-only system. 3D
pixel sensors are promising candidates for the innermost layers of the Pixel
detector due to their excellent radiation hardness at low operation voltages
and low power dissipation at moderate temperatures. Recent developments of 3D
sensors for the HL-LHC are presented.Comment: 8 pages, 5 figures, International Workshops on Radiation Imaging
Detectors 201
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