The beta+-decay half-lives of the neutron-deficient, odd-odd, N = Z nuclei, 74Rb, 78Y, 82NB and 86Tc were measured following the fragmentation of a primary 92Mo beam at an energy of 60 MeV per nucleon at the GANIL laboratory, France. They were measured by correlating beta+-decays with the implantation of unambiguously identified fragments. The deduced log10 ft1/2-values are consistent with 0+→ 0+, Fermi superallowed transitions, which together with the measured beta+-detection efficiencies suggest T = 1, 1pi- 0+ ground states for these odd-odd, N = Z nuclei. These data represent the heaviest N = Z systems for which Fermi superallowed decays have been established. The results suggest that these nuclei can be used to extend the mass range used to test the Conserved Vector Current hypothesis of the standard model. In addition, an experiment using the reaction 58Ni + 28Si at a beam energy of 200 MeV was performed at the Laboratorio Nationale di Legnaro, Italy, using the EUROBALL spectrometer together with a charged particle silicon detector ball and an array of liquid scintillator neutron detectors. The measured values of the energies of the evaporated, charged-particles and those of the gamma-ray multiplicity (deduced using the liquid scintillator detectors), are used to implement a novel technique for the channel selection of weakly populated evaporation channels.

A country’s economy is becoming more and more dynamic and complicated in its scale and mobility. So, the concerns of exchange rate economics have become more popular. My research interest is in international economics with its major factor, exchange rates and other macroeconomic variables. Chapter 1 presents a brief introduction of the three studies. Chapter Two investigate the role of exchange rate changes with particular attention to international capital flows. With liberalization of capital movements, international capital movements became free and unrestricted in many emerging market economies as well as developed countries. Using a Vector Auto-regressive (VAR) model for a small open economy in which the endogeneity of exchange rate changes is fully taken into account, I find that capital movements are more likely to be a cause of output fluctuations and current account deficits in developing countries than a channel of equilibrium changes. I also find that domestic currency depreciation is far more likely to be contractionary on domestic output in developing countries than in developed countries. Interestingly, the trade balance improves after depreciation regardless of its output consequence. These findings suggest that there are important differences between developed and developing economies in the way capital movements and exchange rate changes affect and are affected. Chapter Three demonstrates the dynamic relationship between the current account and the real exchange rate in response to permanent and temporary shocks using structural VAR models for seven developed countries and five developing countries. Special focus is given to the issue of the stationarity of the current account. Capital flows are also included to capture external shocks as well as potential structural breaks due to financial liberalization. I find that the results for unit root tests for the current account are ambiguous. By testing two different VAR models, each taking an opposing stance on the stationarity of the current account, I conclude that responses based on a stationary current account are a better fit to the current theoretical view than those based on a nonstationary current account process. Additionally, the real exchange rate and the current account are positively correlated under a permanent shock while two variables are negatively correlated under a monetary shock. I also find that real exchange rate is an endogenous variable, which is not closely related to the temporary factors that affect the current account in the short run. Chapter Four examines the long-run mean reverting behavior of the real exchange rates with its six different definitions for 27 economies using annual data from 1974 to 2003. I find that Purchasing Power Parity (PPP) holds better, and the half-life of the real exchange rates is shorter when the wholesale price index, rather than consumer price index, is used as price level measure. Somewhat surprisingly, there is no evidence that PPP holds better with trade-weighted real exchange rates than with bilateral ones regardless of the price index used. Strong evidence for PPP emerges only with the use of Im, Pesaran, and Shin (2003) panel tests but not with the Levine, Lin, and Chu (2002).

Many studies measuring the occurrence of pharmaceuticals, understanding their environmental fate and the risk they pose to surface water resources have been published. However, very little is known about the relevant transformation products which result from the wide range of biotic and abiotic degradation processes that these compounds undergo in sewers, storage tanks, during engineered treatment and in the environment. Thus, the present study primarily investigated the degradation of the steroid progesterone (P4) in natural systems (rivers), with a focus on the identification and characterisation of transformation products. Initial work focussed on assessing the removal of selected compounds (Diclofenac, Fluoxetine, Propranolol and P4) from reed beds, with identification of transformation products in a field site being attempted. However, it was determined that concentrations of parent compounds and products would be too low to work with in the field, and a laboratory study was designed which focussed on P4. Focus on P4 was based on literature evidence of its rapid biodegradability relative to the other model compounds and its usage patterns globally. River water sampling for the laboratory-based degradation study was carried out at 1 km downstream of four south east England sewage works (Blackbirds, Chesham, High Wycombe and Maple Lodge) effluent discharge points. Suspected P4 transformation products were initially identified from predictions by the EAWAG Biocatalysis Biodegradation Database (EAWAG BBD) and from a literature review. At a later stage of the present work, a replacement model for EAWAG BBD (enviPath) which became available, was used to predict P4 degradation and results were compared. Samples were analysed using low resolution and accurate-mass time-of-flight mass spectrometers. Three degradation studies were conducted. Sampling for all studies was carried out at the same time in the year to minimize temporal variability in conditions and allow for effective comparison of results. Androgenic and progesterone yeast screens were carried out to assess the biological activity of transformation products.

Resumo: Este estudo buscou determinar através da utilização dos isótopos estáveis do carbono a fase em que o bezerro já está apto para ser desmamado e capaz de consumir alimentos sólidos. Para isso foram coletadas ao longo do período experimental amostras de fezes e sangue, para monitorar o comportamento do turnover do carbono em quatro bezerros bubalinos que recebiam dieta C3 em cocho privativo durante amamentação e leite proveniente de búfalas que se alimentavam de pasto C4. As análises isotópicas foram realizadas no Centro de Isótopos Estáveis do Instituto de Biociências da UNESP, campus de Botucatu. Para mensurar o turnover do carbono nos tecidos em determinado intervalo de tempo, foi utilizado o método sigmoidal de regressão de Boltzmann ou a função exponencial do tempo. Os resultados isotópicos das amostras dos animais que foram submetidos à análise por meio do modelo de Boltzmann ou equação exponencial evidenciaram a dinâmica de consumo do grupo durante os primeiros dias de vida. A meia-vida nas fezes do animal 1091 foi de 224,8 dias e no animal 1093 foi de apenas 61,2 dias, no sangue apenas no animal 1093 foi possível determinar a meia-vida, que foi de 125,6 dias e no plasma sangüíneo a meiavida do animal 1091 foi de 63,8 dias, no animal 1093 foi de 88 dias e no animal 1094 foi de 53,3 dias. Portanto, pode-se concluir que fezes não podem ser consideradas marcadores de digesta confiáveis para as condições deste estudo, apenas como indicadores de consumo. Plasma e sangue total foram eficientes em determinar o tempo de desmame para bubalinos Murrah. / Abstract : This study it searched to determine through the use of stable isotopes of carbon the phase where the year-old calf already is apt to be weaned and capable to consume solid foods. For this samples of blood and faeces had been collected throughout the experimental period, to monitor the behavior of turnover of carbon in four buffaloes year-old calves that received privative C3 diet during breast-feeding and milk proceeding from buffalos that if they fed of C4 grass. The isotopic analyses had been carried through in the Steady Isotope Center of the Institute of Biociências of the UNESP, campus of Botucatu. To measure turnover of carbon in fabrics in determined time interval, the sigmoid method of regression of Boltzmann or the exponential function of the time was used. The isotopic results of the samples of the animals that had been submitted to the analysis by means of the model of Boltzmann or exponential equation had evidenced the dynamics of consumption of the group during the first days of life. The stocking-life in faeces of animal 1091 was of 224,8 days and in animal 1093 it was of only 61,2 days, in the blood only in animal 1093 was possible to determine the stocking-life, that was of 125,6 days and in the plasma sanguine the stocking-life of animal 1091 was of 63,8 days, in animal 1093 it was of 88 days and in animal 1094 it was of 53,3 days. Therefore, it can be concluded that faeces cannot be considered true markers of digestibility for the conditions of this study, as only indicating of consumption... (Complete abstract click electronic access below) / Orientador: Carlos Ducatti / Coorientador: André Mendes Jorge / Banca: Fabiana Ribeiro Caldara / Banca: Cyntia Ludovico Martins / Banca: Ciniro Costa / Banca: Alfredo Sampaio Carrijo / Doutor

Denna uppsats undersöker hur förhållandet mellan karaktären, interagerbarheten ochpresentationen påverkar möjligheterna för hur spelaren uppfattar berättelsen i spelenHalf-Life 2(Valve Corperation, 2004), Fallout 3 (Bethesda Game Studio, 2008) ochFahrenheit (Quantic Dream, 2005). Metoden för analyserna är baserat på Aarseths (2007)teorier och går ut på att jag själv spelat spelen och sedan analyserat dessa utifrån minaegna spelupplevelser. Analyserna tar även upp teorier och begrepp från andra forskare, såsom Marie-Laure Ryan, Andrew Rollings och Ernest Adams, Lee Sheldon och UlfWilhelmsson.Metoden för analyserna lyckas plocka fram flera unika berättartekniker och förhållandenfrån spelen. Bland annat den dolda storyn i Half-life 2, den ytterst interagerbara välden iFallout 3 samt de flera olika huvudkaraktärerna i Fahrenheit, och hur dessa påverkarspelarens uppfattning av berättelsen. Förhållandena är dock inte generella, utan unika förvarje spel, vilket medför att resultaten också är det, och kan därför inte ses som reglerutan mer som riktlinjer för hur en berättarteknik kan se ut.

A delayed-coincidence timing spectrometer system was constructed to measure nuclear lifetimes in the picosecond region. The present investigation used the self-comparison method of delayed-coincidence timing. This method used two plastic detectors to obtain the timing information. Two sodium iodine (NaI) detectors were used in conjunction with the plastic detectors to provide energy identification. Significant changes were made to the geometrical detector arrangement to optimize collection of scattered gamma rays by the NaI detectors. The mean line for the first excited states of the sources Co-60 and Cs-134 were measured using the new spectrometer system. The mean life of the 1.33 MeV excited state of Co-60 was measured to by 0.34 + 1.32 psec. The mean life of the 0.605 MeV excited state of Cs-134 was measured to be 6.31 + 2.19 psec and agrees with two previously reported values.Ball State UniversityMuncie, IN 47306

This research combines relational database framework and quantitative equity portfolio models based on the Barra Risk Model Handbook standard steps to design a database and computer platform for multi-factor risk management tasks. The multi-factor model facilitates fast search and efficient selection of descriptors with explanatory power for future stock returns. The design of database is divided into three steps. First, descriptors are calculated and daily-update modules constructed. This study finds 48 key descriptors which play important roles in explaining stock returns of Taiwan. Second, entity relational model is applied to sort out linkages between pieces of important information in the factor model. Lastly, database auto-run procedures are setup to update the latest raw data on a monthly basis. Model parameter update and portfolio rebalancing is hence made seamless to meet practical operation demand for such a platform. The development of the Multi-factor risk model is divided into five main steps. (1) Finding significant descriptors. (2) Forming common factors from descriptors. (3) Developing a multi-factor return model. (4) Developing a multi-factor risk model. (5) Running performance analysis and back-testing. The empirical results show that the average adjusted R-squared of the MFM model is 0.5 during the period of 1998/04~2005/11. For combining descriptors into common factors, we run factor analysis. The multi-collinearity problem existing in the descriptors is well taken care of by such procedures. We use the exponentially weighted averaging method to compute the factor returns and forecast stock ranking. A half-life of 24 months appears to deliver the best performance in Taiwan stock market.

<p>Denna uppsats undersöker hur förhållandet mellan karaktären, interagerbarheten ochpresentationen påverkar möjligheterna för hur spelaren uppfattar berättelsen i spelenHalf-Life 2(Valve Corperation, 2004), Fallout 3 (Bethesda Game Studio, 2008) ochFahrenheit (Quantic Dream, 2005). Metoden för analyserna är baserat på Aarseths (2007)teorier och går ut på att jag själv spelat spelen och sedan analyserat dessa utifrån minaegna spelupplevelser. Analyserna tar även upp teorier och begrepp från andra forskare, såsom Marie-Laure Ryan, Andrew Rollings och Ernest Adams, Lee Sheldon och UlfWilhelmsson.Metoden för analyserna lyckas plocka fram flera unika berättartekniker och förhållandenfrån spelen. Bland annat den dolda storyn i Half-life 2, den ytterst interagerbara välden iFallout 3 samt de flera olika huvudkaraktärerna i Fahrenheit, och hur dessa påverkarspelarens uppfattning av berättelsen. Förhållandena är dock inte generella, utan unika förvarje spel, vilket medför att resultaten också är det, och kan därför inte ses som reglerutan mer som riktlinjer för hur en berättarteknik kan se ut.</p>

High-precision half-life and branching-ratio measurements for the superallowed beta+ emitter 26Alm were performed at the TRIUMF-ISAC radioactive ion beam facility located in Vancouver, Canada. The branching ratio measurement was performed with the 8pi Spectrometer, an array of 20 high-purity germanium detectors, in conjunction with SCEPTAR, a plastic scintillator array used to detect the emitted beta particles. An upper limit of <= 12 ppm at 90% confidence level was found for the second forbidden beta + decay of 26Alm to the first 2+ state at 1809 keV in 26Mg. An inclusive upper limit of <= 15 ppm at 90% confidence level was found when considering all possible non-analogue beta +/EC decay branches of 26Alm, resulting in a superallowed branching ratio of 100.0000+0−0.0015%. The half-life measurement was performed using a 4pi continuous-flow gas proportional counter and fast tape transport system. The resulting value for the 26Alm half-life, T1/2 = 6.34654(76) s, is consistent with, but 2.5 times more precise than, the previous world average, and represents the single most precisely measured half-life of any superallowed emitting nucleus to date. Combining these results with world-average Q-value measurements yields a superallowed beta -decay ft value of 3037.58(60) s, the most precisely determined ft value for any superallowed emitting nucleus to date. Combined with the small, and precisely quoted, theoretical isospin-symmetry-breaking corrections for this nucleus, the corrected Ft value for 26Alm of 3073.1(12) s is also the most precisely determined for any superallowed emitter by nearly a factor of two and now rivals the precision of all the other 12 precisely measured superallowed beta decays combined. The high-precision experimental ft value for 26Alm superallowed decay reported here provides a new benchmark to refine theoretical models of isospin-symmetry-breaking effects in superallowed Fermi beta decays.

Made available in DSpace on 2014-10-09T12:35:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:40Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP