Determinants of Teacher Quality: Pedagogical Excellence Accreditation Program

Garcia, LY (Garcia, Leidy Y.); Cerda, AA (Cerda, Arcadio A.); Donoso-Diaz, S (Donoso-Diaz, Sebastian)Teachers at primary and secondary schools constitute a hey factor in the educative process and learning results of their students. Given the constitutional mandate that defines the slate's responsibility to provide high-quality public education, it must attract. retain and motivate "good" teachers through diverse mechanisms and incentives, and in the Chilean case it must generate efficient mechanisms to evaluate their teaching performance. The Program to Reward Pedagogical Excellence (AEP from its Spanish acronym) conic about in this framework as a mechanism lot evaluation and incentives, because it aims to evaluate significant aspects of the quality of teachers, awarding bonuses to the roost outstanding. Given the importance of educational quality in establishments subsidized by the state (both municipal and private) for the development of the country and society, this work aims to determine the characteristics of teachers who have obtained ALP quality accreditation, through a conditional probit model using data from a longitudinal Teaching Survey (ELD from its Spanish acronym), while also calculating the probability of participating in this program. We conclude that the factors that explain the probability of being accredited are: experience, the family's socioeconomic condition. the mother's educational level, the teacher's educational level training and internships, quality of health conditions, vocation and quality of the AEP program, which have significant hut reduced effect

Willingness to pay for human papillomavirus vaccine in Metropolitan Santiago, Chile

Cerda, AA (Cerda, Arcadio A ; Gaete, FI (Gaete, Fabian I.) ; Pizarro, TH (Pizarro, Tomas H.). Univ Talca, Fac Ciencias Empresariales, Talca, ChileWillingness to pay for human papillomavirus vaccine in Metropolitan Santiago, Chile Background: Human papillomavirus (HPV) infection is a risk factor for cervical cancer and can be prevented with the HPV vaccine. Aim: To explore the willingness of parents to pay for HPV vaccine for their offspring. Material and Methods: A survey about the willingness to pay for HPV vaccine was answered by 386 individuals of the highest socioeconomic level who had a daughter aged between 12 and 18 years. The survey included information about the risks of HPV infection. Results: Parents would pay a mean of US$ 758 for the vaccine. Twenty five percent of parents were not willing to pay for it. If the cost of the vaccine would be reduced by 50%, only 4% of parents would not pay for it. The willingness to pay is associated with the price of the vaccine, the income level of respondents and the size of the family. Conclusions: Most respondents would pay for HPV vaccine for their daughters, despite the relatively high cost. (Rev Med Chile 2013; 141: 167-172)

Consumer preferences and willingness to pay for organic apples

Cerda, AA (reprint author), Univ Talca, Fac Ciencias Empresariales, 2 Norte 685, Talca, Chile.This study provides marketing data regarding consumer preferences and willingness to pay for organic agricultural products in Chile. The main objectives of this study were to assess consumer willingness to pay for organic apples and to determine the main attributes that consumers look for when purchasing apples. The methodology applied to reach the first objective was the contingent valuation method using a logistic probability function and a single-bound dichotomous choice format. Additionally, this study estimates the marginal willingness to pay (WTP) of consumers for organic apples by using conjoint analysis with ranking procedures. This study was performed in the city of Talca, Chile, where a total of 400 individuals from a probability sampling were interviewed. The results of our study show that the estimation of part-worth utilities of each attribute confirms that the Fuji variety, organic method of production, sweet apples and lowest price are the most preferred levels of each attribute. However, an analysis of the relative utility index shows that price and variety are much more important to consumer choice and behavior than the method of production and flavor. Finally, our study shows a positive willingness to pay an additional 130 Chilean pesos per kilogram for organic apples and a greater preference for apples produced organically than by conventional methods. These results provide important information about market opportunities as well as policy implementation regarding the production of organic agricultural products

The role of matter density uncertainties in the analysis of future neutrino factory experiments

Matter density uncertainties can affect the measurements of the neutrino oscillation parameters at future neutrino factory experiments, such as the measurements of the mixing parameters $\theta_{13}$ and \deltacp. We compare different matter density uncertainty models and discuss the possibility to include the matter density uncertainties in a complete statistical analysis. Furthermore, we systematically study in which measurements and where in the parameter space matter density uncertainties are most relevant. We illustrate this discussion with examples that show the effects as functions of different magnitudes of the matter density uncertainties. We find that matter density uncertainties are especially relevant for large \stheta \gtrsim 10^{-3}. Within the KamLAND-allowed range, they are most relevant for the precision measurements of \stheta and \deltacp, but less relevant for ``binary'' measurements, such as for the sign of \ldm, the sensitivity to \stheta, or the sensitivity to maximal CP violation. In addition, we demonstrate that knowing the matter density along a specific baseline better than to about 1% precision means that all measurements will become almost independent of the matter density uncertainties.Comment: 21 pages, 7 figures, LaTeX. Final version to be published in Phys. Rev.

Helicity Amplitudes of the Lambda(1670) and two Lambda(1405) as dynamically generated resonances

We determine the helicity amplitudes A_1/2 and radiative decay widths in the transition Lambda(1670) to gamma Y (Y=Lambda or Sigma^0). The Lambda(1670) is treated as a dynamically generated resonance in meson-baryon chiral dynamics. We obtain the radiative decay widths of the Lambda(1670) to gamma Lambda as 3 \pm 2 keV and to gamma Sigma^0 as 120 \pm 50 keV. Also, the Q^2 dependence of the helicity amplitudes A_1/2 is calculated. We find that the K Xi component in the Lambda(1670) structure, mainly responsible for the dynamical generation of this resonance, is also responsible for the significant suppression of the decay ratio Gamma_{gamma Lambda}/Gamma_{gamma Sigma^0}. A measurement of the ratio would, thus, provide direct access to the nature of the Lambda(1670). To compare the result for the Lambda(1670), we calculate the helicity amplitudes A_1/2 for the two states of the Lambda(1405). Also, the analytic continuation of Feynman parameterized integrals of more complicated loop amplitudes to the complex plane is developed which allows for an internally consistent evaluation of A_1/2.Comment: 15 pages, 8 figure

Association of Circulating Ketone Bodies With Functional Outcomes After ST-Segment Elevation Myocardial Infarction

Background: Circulating ketone bodies (KBs) are increased in patients with heart failure (HF), corresponding with increased cardiac KB metabolism and HF severity. However, the role of circulating KBs in ischemia/reperfusion remains unknown. Objectives: This study sought to investigate longitudinal changes of KBs and their associations with functional outcomes in patients presenting with ST-segment elevation myocardial infarction (STEMI). Methods: KBs were measured in 369 participants from a randomized trial on early metformin therapy after STEMI. Nonfasting plasma concentrations of KBs (β-hydroxybutyrate, acetoacetate, and acetone) were measured by nuclear magnetic resonance spectroscopy at presentation, at 24 hours, and after 4 months. Myocardial infarct size and left ventricular ejection fraction (LVEF) were determined by cardiac magnetic resonance imaging at 4 months. Associations of circulating KBs with infarct size and LVEF were determined using multivariable linear regression analyses. Results: Circulating KBs were high at presentation with STEMI (median total KBs: 520 μmol/L; interquartile range [IQR]: 315-997 μmol/L). At 24 hours after reperfusion, KBs were still high compared with levels at 4-month follow-up (206 μmol/L [IQR: 174-246] vs 166 μmol/L [IQR: 143-201], respectively; P < 0.001). Increased KB concentrations at 24 hours were independently associated with larger myocardial infarct size (total KBs, per 100 μmol/L: β = 1.56; 95% confidence interval: 0.29-2.83; P = 0.016) and lower LVEF (β = −1.78; 95% CI: (−3.17 to −0.39; P = 0.012). Conclusions: Circulating KBs are increased in patients presenting with STEMI. Higher KBs at 24 hours are associated with functional outcomes after STEMI, which suggests a potential role for ketone metabolism in response to myocardial ischemia. (Metabolic Modulation With Metformin to Reduce Heart Failure After Acute Myocardial Infarction: Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction (GIPS-III): a Randomized Controlled Trial; NCT01217307

Three body systems with strangeness and exotic systems

We report on four $\Sigma$'s and three $\Lambda$'s, in the 1500 - 1800 MeV region, as two meson - one baryon S-wave $(1/2)^+$ resonances found by solving the Faddeev equations in the coupled channel approach, which can be associated to the existing $S$ = -1, $J^P= 1/2^+$ low lying baryon resonances. On the other hand we also report on a new, hidden strangeness $N^*$ state, mostly made of $K \bar{K} N$, with mass around 1920 MeV, which we think could be responsible for the peak seen in the $\gamma p \to K^+ \Lambda$ around this energy. Finally we address a very novel topic in which we show how few body systems of several $\rho$ mesons can be produced, with their spins aligned up to J=6, and how these states found theoretically can be associated to several known mesons with spins J=2,3,4,5,6.Comment: Talk at the 21st European Conference on Few Body Problems in Physics, Salamanca, Sep. 201

Theory and simulation of quantum photovoltaic devices based on the non-equilibrium Green's function formalism

This article reviews the application of the non-equilibrium Green's function formalism to the simulation of novel photovoltaic devices utilizing quantum confinement effects in low dimensional absorber structures. It covers well-known aspects of the fundamental NEGF theory for a system of interacting electrons, photons and phonons with relevance for the simulation of optoelectronic devices and introduces at the same time new approaches to the theoretical description of the elementary processes of photovoltaic device operation, such as photogeneration via coherent excitonic absorption, phonon-mediated indirect optical transitions or non-radiative recombination via defect states. While the description of the theoretical framework is kept as general as possible, two specific prototypical quantum photovoltaic devices, a single quantum well photodiode and a silicon-oxide based superlattice absorber, are used to illustrated the kind of unique insight that numerical simulations based on the theory are able to provide.Comment: 20 pages, 10 figures; invited review pape

Grafting of Poly(methyl methacrylate) Brushes from Magnetite Nanoparticles Using a Phosphonic Acid Based Initiator by Ambient Temperature Atom Transfer Radical Polymerization (ATATRP)

Poly(methyl methacrylate) in the brush form is grown from the surface of magnetite nanoparticles by ambient temperature atom transfer radical polymerization (ATATRP) using a phosphonic acid based initiator. The surface initiator was prepared by the reaction of ethylene glycol with 2-bromoisobutyrl bromide, followed by the reaction with phosphorus oxychloride and hydrolysis. This initiator is anchored to magnetite nanoparticles via physisorption. The ATATRP of methyl methacrylate was carried out in the presence of CuBr/PMDETA complex, without a sacrificial initiator, and the grafting density is found to be as high as 0.90 molecules/nm2. The organic–inorganic hybrid material thus prepared shows exceptional stability in organic solvents unlike unfunctionalized magnetite nanoparticles which tend to flocculate. The polymer brushes of various number average molecular weights were prepared and the molecular weight was determined using size exclusion chromatography, after degrafting the polymer from the magnetite core. Thermogravimetric analysis, X-ray photoelectron spectra and diffused reflection FT-IR were used to confirm the grafting reaction

Hidden beauty baryon states in the local hidden gauge approach with heavy quark spin symmetry

Using a coupled-channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-baryon interaction with hidden beauty and obtain several new states of N around 11 GeV. We consider the basis of states eta (b) N, I'N, BI > (b) , BI pound (b) , B (*) I > (b) , B (*) I pound (b) , B (*) I pound (b) (*) and find four basic bound states which correspond to BI pound (b) , BI pound (b) (*) , B (*) I pound (b) and B (*) I pound (b) (*) , decaying mostly into eta (b) N and I'N and with a binding energy about 50-130 MeV with respect to the thresholds of the corresponding channel. All of them have isospin I = 1/2 , and we find no bound states or resonances in I = 3/2 . The BI pound (b) state appears in J = 1/2 , the BI pound (b) (*) in J = 3/2 , the B (*) I pound (b) appears nearly degenerate in J = 1/2 , 3/2 and the B (*) I pound (b) (*) appears nearly degenerate in J = 1/2 , 3/2, 5/2. These states have a width from 2-110 MeV, with conservative estimates of uncertainties, except for the one in J = 5/2 which has zero width since it cannot decay into any of the states of the basis chosen. We make generous estimates of the uncertainties and find that within very large margins these states appear bound