Influência da sociedade no desenvolvimento tecnológico: um estudo das concepções de graduandos brasileiros do Estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação de modelos empíricos para determinação da taxa de passagem de caprinos em crescimento

Pós-graduação em Zootecnia - FCAV

Uma investigação discursivo-funcional das orações concessivas introduzidas por aunque em dados do espanhol peninsular

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um estudo sobre os diferentes valores modais do verbo 'poder' em entrevistas jornalísticas do espanhol

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Selecting for rust (Puccinia psidii) reistance in Euclyptus grandis in São Paulo state, Brazil

In Brazil, Eucalyptus grandis is a key species for wood production. However, some genotypes are susceptible to rust (Puccinia psidii), mainly in São Paulo State, where climatic conditions are favorable for its development. Rust represents a high economic risk to forest companies because of the high potential of damage to commercial eucalypt plantations. The aims of the present study were (i) to select progenies of E. grandis for stability and adaptability regarding resistance to rust at different locations; (ii) compare the selections under these different climatic conditions; and (iii) compare rust severity in the field with the theoretical model. We observed that climatic conditions were extremely influential factors for rust development, but even under favorable conditions for disease development, we found rust-resistant progenies. In sites unfavorable for rust development, we detected highly susceptible progenies. We found significant correlation among the genetic material, environmental conditions and disease symptoms, however, we observed a simple genotype-environmental interaction and significant genetic variability among the progenies. The average heritability was high among the progenies in all sites, indicating substantial genetic control for rust resistance. We also observed a good relationship between rust severity in the field and the theoretical model that considered annual average temperature and leaf wetness.

Relação entre risco de erosão e distância de camalhões em estradas florestais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A experiência materna com seu recém-nascido em fototerapia

Pós-graduação em Enfermagem - FMB

Essays on Industrial Organization and Environmental Economics

This dissertation studies environmental regulation issues in the hog production industry as well as forces behind the reorganization of the industry during the past two decades. Federal and State-level environmental regulations imposed on U.S. hog production during the year 2003 are examined in Chapter 1. Based on the number of regulations passed by the Federal government and states, the 2003 regulatory index is constructed. The regulatory stringency index suggests that state-level regulations vary across states and have increased over the years. In addition, state-level regulations are more stringent than federal regulations. Chapter 2 develops an empirically implementable theoretical model which allows us to investigate the long-run effects of environmental regulations on the U.S. hog industry. Hog feeding operations (HFOs) are divided into large feeding operations (LHFOs) and small feeding operations (SHFOs). The impact of the presence of a large number of LHFOs on the entry and exit of CHFOs is also examined. Results of this study suggest that: Increased state-level regulation stringency significantly lowers the output of SHFOs; increased state-level regulation stringency significantly lowers the output of LHFOs; increased state-level regulation stringency significantly lowers the number of SHFOs; SHFO output rises significantly in states that have a greater number of LHFOs; LHFO output rises significantly in states that have a greater number of LHFOs; the number of SHFOs significantly increases in states that have a greater numbers of LHFOs; regulation increases the average SHFO size; and regulation decreases the average LHFO size. Chapter 3 examines the importance of input availability, market attractiveness, agglomeration economies and environmental regulations on the reorganization of U.S. hog production for a panel of 22 U.S. hog producing states which include, Northern states, Southern states and Midwest states for the period 1994-2006. Results from this study suggest that: Hog production in a state is positively affected by hog production in a nearby state, confirming the presence of agglomeration economies; Environmental regulations and high corn price have negative effects on state-level U.S. hog production; High hog prices, and favorable labor cost, and land values attract hog production; and transportation cost has no effect on hog production. Advisors: Azzeddine Azzam and Karina Schoengold

Health and Growth: Causality through Education

Purpose--The paper theoretically and empirically investigates the impact on human capital investment decisions and income growth of lowered life expectancy as a result of HIV/AIDS and other diseases. Design/methodology/approach--The theoretical model is a three-period overlapping generations model where individuals go through three stages in their life, namely, young, adult and old. The model extends existing theoretical models by allowing the probability of premature death to differ for individuals at different life stage, and by allowing for stochastic technological advances. The empirical investigation focuses on the effect of HIV/AIDS on life expectancy and on the role of health on educational investments and growth. We address potential endogeneity by using various strategies, such as controlling for country specific time-invariant unobservables and by using the male circumcision rate as an instrumental variable for HIV/AIDS prevalence. Findings--We show theoretically that an increased probability of premature death leads to less investment in human capital, and consequently slower growth. Empirically we show that HIV/AIDS has resulted in a substantial decline in life expectancy in African countries and these falling life expectancies are indeed associated with lower educational attainment and slower economic growth world wide. Originality/value--The theoretical and empirical findings reveal a causal link flowing from health to growth, which has been largely overlooked by the existing literature. The main implication is that health investments, that decrease the incidence of diseases like HIV/AIDS resulting on increases in life expectancy, through its complementarity with human capital investments lead to long run growth..

Design of a Comb Generator for High Capacity Coherent-WDM Systems

This paper presents a theoretical model developed for estimating the power, the optical signal to noise ratio and the number of generated carriers in a comb generator, having as a reference the minimum optical signal do noise ratio at the receiver input, for a given fiber link. Based on the recirculating frequency shifting technique, the generator relies on the use of coherent and orthogonal multi-carriers (Coherent-WDM) that makes use of a single laser source (seed) for feeding high capacity (above 100 Gb/s) systems. The theoretical model has been validated by an experimental demonstration, where 23 comb lines with an optical signal to noise ratio ranging from 25 to 33 dB, in a spectral window of similar to 3.5 nm, are obtained.

Changes in a nanoparticle's spectroscopic signal mediated by the local environment

Using a first-principles theoretical model the adsorption of a methyl radical on different sized silver nanoparticles is compared to the adsorption of the same radical on model surfaces. Calculations of our structural, dynamical and electronic properties indicated that small changes in the local environment will lead to small changes in infrared (IR) wavenumbers, but in dramatic changes in the IR signal. Our calculations indicate the lower the adsorption site coordination, the higher is the signal strength, suggesting that small changes in the electronic charge distribution will result in bigger changes in the polarizability and hence in the spectroscopic signal intensity. This effect explains, among others, the signal magnification observed for nanoparticles in surface enhanced Raman spectroscopic (SERS) experiments.

Band structure calculations of InP wurtzite/zinc-blende quantum wells

Semiconductor nanowhiskers (NWs) made of III-V compounds exhibit great potential for technological applications. Controlling the growth conditions, such as temperature and diameter, it is possible to alternate between zinc-blende (ZB) and wurtzite (WZ) crystalline phases, giving origin to the so called polytypism. This effect has great influence in the electronic and optical properties of the system, generating new forms of confinement to the carriers. A theoretical model capable to accurately describe electronic and optical properties in these polytypical nanostructures can be used to study and develop new kinds of nanodevices. In this study, we present the development of a wurtzite/zinc-blende polytypical model to calculate the electronic band structure of nanowhiskers based on group theory concepts and the k.p method. Although the interest is in polytypical superlattices, the proposed model was applied to a single quantum well of InP to study the physics of the wurtzite/zinc-blende polytypism. By the analysis of our results, some trends can be predicted: spatial carriers' separation, predominance of perpendicular polarization (xy plane) in the luminescence spectra, and interband transition blueshifts with strain. Also, a possible range of values for the wurtzite InP spontaneous polarization is suggested. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4767511]

Imaginative construction of care: the nursing professional experience in a remote care service

The direction of care delivery goes from the action to the being; a process built from professional experience, which gains special characteristics when the service is delivered by telephone. The goal of this research was to understand the interaction between professionals and users in a remote care service; to do so, a research is presented, using Grounded Theory and Symbolic Interactionism as theoretical references. Data were collected through eight interviews with professionals who deliver care by telephone. The theoretical understanding permitted the creation of the theoretical model of the Imaginative Construction of Care, which shows the interaction processes the professional experiences when delivering care by telephone. In this model, individual and social facts are added, showing the link between the concepts, with special emphasis on uncertainty, sensitivity and professional responsibility, as essential components of this experience.

Reliability and validity of spirituality questionnaire by Parsian and Dunning in the Spanish version

The aim of this methodological study was to translate, culturally adapt and assess the internal consistency and validity of the Spanish version of the "Spirituality Questionnaire". The sample comprised 204 young people between 18 and 25 years of age from two universities in Bogota. Cronbach's Alpha was used for reliability, while groups of experts and young people were used for construct validity. The reliability score of the total instrument was 0.88. The overall index of content validity corresponded to 0.90. Exploratory factor analysis showed that four factors explain 52.60% of the variance. The originally proposed theoretical model was confirmed and, in two dimensions, a different structure was proposed. In conclusion, the instrument "Spirituality Questionnaire" by Parsian and Dunning is reliable and valid in the Spanish version.

Freeze-drying microscopy in mathematical modeling of a biomaterial freeze-drying

Transplantation brings hope for many patients. A multidisciplinary approach on this field aims at creating biologically functional tissues to be used as implants and prostheses. The freeze-drying process allows the fundamental properties of these materials to be preserved, making future manipulation and storage easier. Optimizing a freeze-drying cycle is of great importance since it aims at reducing process costs while increasing product quality of this time-and-energy-consuming process. Mathematical modeling comes as a tool to help a better understanding of the process variables behavior and consequently it helps optimization studies. Freeze-drying microscopy is a technique usually applied to determine critical temperatures of liquid formulations. It has been used in this work to determine the sublimation rates of a biological tissue freeze-drying. The sublimation rates were measured from the speed of the moving interface between the dried and the frozen layer under 21.33, 42.66 and 63.99 Pa. The studied variables were used in a theoretical model to simulate various temperature profiles of the freeze-drying process. Good agreement between the experimental and the simulated results was found.