4,049 research outputs found

    Adult Education in the End of the Century: A Reflective Review from Portugal

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    In this paper we review adult education policies in Portugal from 1974 until 1999, and we also try to provide a realistic portrait of the current situation. Our main aim is to give suggestions to guide researchers in this field of work

    On the relationship between pump chirp and single-photon chirp in spontaneous parametric downconversion

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    We study the chronocyclic character, i.e. the joint temporal and spectral properties, of the single-photon constituents of photon pairs generated by spontaneous parametric down conversion. In particular we study how single photon properties, including purity and single-photon chirp, depend on photon pair properties, including the type of signal-idler spectral and correlations and the level of pump chirp.Comment: 13 pages, 6 figure

    Utilization of Cooked Cassava and Taro as Alternative Feed in Enhancing Pig Production in Ecuadorian Backyard System

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    Pork production in Ecuador is of significant economic and nutritional importance. Many of these operations are family- or backyard-based and utilize alternative feed ingredients to reduce production costs. The current study aimed to determine the chemical composition of cooked cassava and taro, and to evaluate their inclusion in the feed of backyard pigs during the growth and fattening phases. A total of 42 castrated pigs from two geographic locations in Ecuador were studied over a period of 100 days, during which their weight and measurements were recorded at three-week intervals. At the end of the experiment, ileum samples were collected from the slaughtered pigs in order to calculate the apparent digestibility of the feed. The crude protein levels of cassava and taro were found to be 3.2% and 2.1%, respectively. The combination of cooked cassava and taro was found to be a suitable replacement for corn, with the best results observed in the group receiving a diet incorporating 21% each of cassava and taro. Analysis of the ileal content also revealed that this group exhibited the highest nitrogen assimilation from the diet

    Josephson surface plasmons in spatially confined cuprate superconductors

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    In this work, we generalize the theory of localized surface plasmons to the case of high-Tc cuprate superconductors, spatially confined in the form of small spherical particles. At variance from ordinary metals, cuprate superconductors are characterized by a low-energy bulk excitation known as the Josephson plasma wave (JPW), arising from interlayer tunneling of the condensate along the c-axis. The effect of the JPW is revealed in a characteristic spectrum of surface excitations, which we call Josephson surface plasmons. Our results, which apply to any material with a strongly anisotropic electromagnetic response, are worked out in detail for the case of multilayered superconductors supporting both low-frequency (acoustic) and transverse-optical JPW. Spatial confinement of the Josephson plasma waves may represent a new degree of freedom to engineer their frequencies and to explore the link between interlayer tunnelling and high-Tc superconductivity

    Two-photon decays of hadronic molecules

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    In many calculations of the two--photon decay of hadronic molecules, the decay matrix element is estimated using the wave function at the origin prescription, in analogy to the two-photon decay of parapositronium. We question the applicability of this procedure to the two-photon decay of hadronic molecules for it introduces an uncontrolled model dependence into the calculation. As an alternative approach, we propose an explicit evaluation of the hadron loop. For shallow bound states, this can be done as an expansion in powers of the range of the molecule binding force. In the leading order one gets the well-known point-like limit answer. We estimate, in a self-consistent and gauge invariant way, the leading range corrections for the two-photon decay width of weakly bound hadronic molecules emerging from kaon loops. We find them to be small. The role of possible short-ranged operators and of the width of the scalars remains to be investigated.Comment: LaTeX2e, 26 pages, new figure and additional appendix added, version to appear in Phys.Rev.

    The Radiative Decay of Vector Mesons

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    In this paper, radiative decays ρ0π+πγ,π0π0γ\rho^0 \to \pi^+\pi^-\gamma, \pi^0\pi^0\gamma ,ϕK+Kγ,K0K0ˉγ\phi \to K^+K^-\gamma, K^0 \bar{K^0}\gamma are studied systematically in the U(3)_L\timesU(3)_R chiral theory of mesons. The theoretical differential spectrum with respect to photon energy and branch ratio for ρ0π+πγ\rho^0 \to \pi^+\pi^-\gamma agree well with the experimental data. Differential spectrums and branch ratios for ρ0π0π0γ,ϕK+Kγ,ϕK0K0ˉγ\rho^0 \to \pi^0\pi^0\gamma, \phi \to K^+ K^-\gamma,\phi \to K^0\bar{K^0}\gamma are predicted. The process ϕK0K0ˉγ\phi \to K^0 \bar{K^0} \gamma is relevant to precision measurment of CP-violation parameters in the kaon systerm at a ϕ\phi-factory. We give a complete estimate of the branch ratio for this decay process by including scalar resonance f0,a0f_0, a_0 poles, nonresonant smooth amplitude and an abnormal parity process with KK^* pole which hasn't been considered before. We conclude that processes with intermediate KK^* do not pose a potential background problem for ϕK0Kˉ0\phi\to K^0\bar{K}^0 CP violation experiments.Comment: Revtex file, 12 pages, 9 eps figure

    Inverse association of circulating SIRT1 and adiposity. A study on underweight, normal weight, and obese patients

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    Context: Sirtuins (SIRTs) are NAD+-dependent deacetylases, cellular sensors to detect energy availability, and modulate metabolic processes. SIRT1, the most studied family member, influences a number of tissues including adipose tissue. Expression and activity of SIRT1 reduce with weight gain and increase in conditions of starvation. Objective: To focus on SIRT1 plasma concentrations in different conditions of adiposity and to correlate SIRT1 with fat content and distribution, energy homeostasis and inflammation in under-weight, normal-weight, and obese individuals. Materials and Methods: 21 patients with anorexia nervosa, 26 normal-weight and 75 patients with obesity were evaluated. Body fat composition by dual-energy X-ray absorptiometry, ultrasound liver adiposity, echocardiographic epicardial fat thickness (EFT), inflammatory (ESR, CRP, and fibrinogen), and metabolic (FPG, insulin, LDL- and HDL-cholesterol, triglycerides) parameters, calculated basal metabolic rate (BMR) and plasma SIRT1 (ELISA) were measured. Results: SIRT1 was significantly higher in anorexic patients compared to normal-weight and obese patients (3.27 ± 2.98, 2.27 ± 1.13, and 1.36 ± 1.31 ng/ml, respectively). Linear regression models for each predictor variable adjusted for age and sex showed that SIRT1 concentration was inversely and significantly correlated with EFT, fat mass %, liver fat content, BMR, weight, BMI, WC, LDL-cholesterol, insulin, ESR. Stepwise multiple regression analysis revealed that age and EFT were the best independent correlates of SIRT1 (β = -0.026 ± 0.011, p = 0.025, and β = -0.516 ± 0.083, p < 0.001, respectively). Conclusions: Plasma SIRT1 shows a continuous pattern that inversely follows the whole spectrum of adiposity. SIRT1 significantly associates with EFT, a strong index of visceral fat phenotype, better than other indexes of adiposity studied here

    Multidimensional Digital Signal Estimation Using Kalman’s Theory for Computer-Aided Applications

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    In this paper, we analyze the Multidimensional Kalman Algorithm to estimate a signal corrupted by white Gaussian noise. Because the theory provide a good solution to the problem with a large number of signals, we developed an algorithm for three-dimensional Kalman filtering applied to the positioning problem (latitude, altitude and longitude) of a stationary object based on GPS signals. This application was selected because the incoming signals of the GPS encounters some noise on its way to the receiver, which is originated from different types of sources, the consequences are that the received signals are noisy, therefore inaccurate. The signals are digitally processed, and the implementation may be carried out on a computer-aided system for a specific application.Consejo Nacional de Ciencia y TecnologíaUniversidad de Guanajuat

    Innovation in Early music festivals. domains, strategies and outcomes

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    This chapter takes an in-depth look at innovation in cultural festivals, in particular in early music festivals, which is a type of festival aimed at a generally local and minority audience. It identifies and analyses types of innovations, the strategies used by early music festivals to innovate and the results of these innovations in the framework of a collaboration with the European Early Music Network, whose members, festival directors, agreed to participate in the survey designed for this purpose. Different types of product, production and pre-production process, marketing and communication innovations are identified but also maintain traditional products and communication channels for their most loyal audience. The analysis shows that early music festivals engage in a range of innovations and employ a meaningful combination of innovation strategies with diverse stakeholders. Innovation efforts have led to several intangible and tangible improvements, including increased prestige and bigger and more diverse audiences. Although some of the innovations identified are common to other cultural festivals, many product innovations depend on musicology research; therefore, similar to other science-based sectors, relationships with researchers are very important
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