Calculation of light nucleus reaction cross sections in Geant4

Total reaction cross sections of light projectile nucleus (H-2, H-3, He-3 and He-4) interactions with nuclei are calculated using Geant4 models, and compared with experimental data. It is shown that the models give various predictions at low energies, in the region of the Coulomb barrier. "Shen model" (W.-Q. Shen et al., Nucl. Phys. {\bf A491} (1989) 130) is identified as an improvement over other models.Comment: 2 pages text, 8 figure

Iterative design of dynamic experiments in modeling for optimization of innovative bioprocesses

Finding optimal operating conditions fast with a scarce budget of experimental runs is a key problem to speed up the development and scaling up of innovative bioprocesses. In this paper, a novel iterative methodology for the model-based design of dynamic experiments in modeling for optimization is developed and successfully applied to the optimization of a fed-batch bioreactor related to the production of r-interleukin-11 (rIL-11) whose DNA sequence has been cloned in an Escherichia coli strain. At each iteration, the proposed methodology resorts to a library of tendency models to increasingly bias bioreactor operating conditions towards an optimum. By selecting the ‘most informative’ tendency model in the sequel, the next dynamic experiment is defined by re-optimizing the input policy and calculating optimal sampling times. Model selection is based on minimizing an error measure which distinguishes between parametric and structural uncertainty to selectively bias data gathering towards improved operating conditions. The parametric uncertainty of tendency models is iteratively reduced using Global Sensitivity Analysis (GSA) to pinpoint which parameters are keys for estimating the objective function. Results obtained after just a few iterations are very promising.Fil: Cristaldi, Mariano Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Grau, Ricardo José Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Martínez, Ernesto Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; Argentin

Using Random Forests to Describe Equity in Higher Education: A Critical Quantitative Analysis of Utah’s Postsecondary Pipelines

The following work examines the Random Forest (RF) algorithm as a tool for predicting student outcomes and interrogating the equity of postsecondary education pipelines. The RF model, created using longitudinal data of 41,303 students from Utah\u27s 2008 high school graduation cohort, is compared to logistic and linear models, which are commonly used to predict college access and success. Substantially, this work finds High School GPA to be the best predictor of postsecondary GPA, whereas commonly used ACT and AP test scores are not nearly as important. Each model identified several demographic disparities in higher education access, most significantly the effects of individual-level economic disadvantage. District- and school-level factors such as the proportion of Low Income students and the proportion of Underrepresented Racial Minority (URM) students were important and negatively associated with postsecondary success. Methodologically, the RF model was able to capture non-linearity in the predictive power of school- and district-level variables, a key finding which was undetectable using linear models. The RF algorithm outperforms logistic models in prediction of student enrollment, performs similarly to linear models in prediction of postsecondary GPA, and excels both models in its descriptions of non-linear variable relationships. RF provides novel interpretations of data, challenges conclusions from linear models, and has enormous potential to further the literature around equity in postsecondary pipelines

A fast Monte-Carlo method with a Reduced Basis of Control Variates applied to Uncertainty Propagation and Bayesian Estimation

The Reduced-Basis Control-Variate Monte-Carlo method was introduced recently in [S. Boyaval and T. Leli\`evre, CMS, 8 2010] as an improved Monte-Carlo method, for the fast estimation of many parametrized expected values at many parameter values. We provide here a more complete analysis of the method including precise error estimates and convergence results. We also numerically demonstrate that it can be useful to some parametrized frameworks in Uncertainty Quantification, in particular (i) the case where the parametrized expectation is a scalar output of the solution to a Partial Differential Equation (PDE) with stochastic coefficients (an Uncertainty Propagation problem), and (ii) the case where the parametrized expectation is the Bayesian estimator of a scalar output in a similar PDE context. Moreover, in each case, a PDE has to be solved many times for many values of its coefficients. This is costly and we also use a reduced basis of PDE solutions like in [S. Boyaval, C. Le Bris, Nguyen C., Y. Maday and T. Patera, CMAME, 198 2009]. This is the first combination of various Reduced-Basis ideas to our knowledge, here with a view to reducing as much as possible the computational cost of a simple approach to Uncertainty Quantification

Mark-Up Pricing in Bulgarian Manufacturing

The pricing policy of Bulgarian manufacturing firms is analysed in the paper in the context of the theory of the price-setting behaviour of firms endowed with market power, and more specifically, using the notion of mark-up pricing. Using some recent derivations in the literature, we estimate mark-up ratios for Bulgarian manufacturing sectors at the NACE 2-digit and NACE 3-digit levels. The estimated mark-ups are then tested against a set of variables measuring the degree of competitive pressure on a sectoral level.http://deepblue.lib.umich.edu/bitstream/2027.42/39773/3/wp389.pd

Estimating the minimally important difference (MID) of the Diabetes Health Profile-18 (DHP-18) for Type 1 and Type 2 Diabetes Mellitus

Aims: The DHP-18 is a widely used measure of health related quality of life in diabetes mellitus but it is unclear what constitutes a meaningful change in score on each domain. The aim of this study was to establish estimates for the minimally important difference (MID) for each of the domains. Methods: The MID for each domain was estimated using both anchor and distribution based approaches which were applied to data from both the United Kingdom and France. A range of anchors were tested. Results: A global health change anchor was found to be more acceptable for Type 1 diabetes than for Type 2. MID estimates varied by domain, by estimation approach used, and by diabetes type. For Type 1 diabetes the Psychological Distress domain estimates ranged from 2.86 to 11.05, Barriers to Activity domain from 2.87 to 11.32 and Disinhibited Eating domain from 1.03 to 11.53. For Type 2 diabetes the Psychological Distress estimates ranged from 0.94 to 9.71; Barriers to Activity from 1.66 to 9.88 and Disinhibited Eating from 0.90 to 11.64. Conclusions: This is the first attempt to derive estimates for the MID of an English language measure of health related quality of life in diabetes. For Type 1 diabetes we recommend using the mean MID value using both approaches. For Type 2 we recommend applying more weight to the distribution based estimations. The MID values identified in this study will help clinicians and researchers using the DHP-18 to identify clinically meaningful change in patient reported outcomes

The determinants of sovereign bond yield spreads in the EMU

Mestrado em Economia Monetária e FinanceiraUm conjunto de dados de painel de países da área do euro foi utilizado para avaliar os determinantes dos spreads de rentabilidade de títulos soberanos do primeiro trimestre de 1995 ao último trimestre de 2017. No período anterior à crise financeira, os spreads foram determinados principalmente pela dívida esperada em relação ao PIB, fator de risco de crédito e crescimento econômico. Com a erupção da crise financeira, a análise sugere que os mercados começaram a levar em consideração mais fundamentos para determinar o preço dos spreads, como risco de liquidez e risco internacional. Concluiu-se também que existe uma diferença entre os determinantes do spread entre o grupo periferico e o grupo central.A panel dataset of euro area countries was used to assess the determinants of sovereign bond yield spreads from first quarter of 1995 to the last quarter of 2017. In the period before the financial crisis, the government bond yield spreads were mostly determined by the expected debt to GDP, the credit risk factor and economic growth. With the eruption of the financial crisis, the analysis suggests that markets have started to take into consideration more fundamentals to determine the price of government bond yield spreads, such as liquidity risk and international risk. It was also concluded that there is a difference between the determinants of the government bond yield spread of core and periphery group.info:eu-repo/semantics/publishedVersio