Excitons in type-II quantum dots: Finite offsets

Quantum size effects for an exciton attached to a spherical quantum dot are calculated by a variational approach. The band line-ups are assumed to be type-II with finite offsets. The dependence of the exciton binding energy upon the dot radius and the offsets is studied for different sets of electron and hole effective masses

EVALUATION OF GREEN LASER SOURCE ADDITIVE MANUFACTURING TECHNOLOGY FOR ACCELERATOR APPLICATIONS WITH ULTRA-HIGH VACUUM REQUIREMENTS

Additive Manufacturing (AM) offers different benefits such as efficient material usage, reduced production time and design freedom. Moreover, with continuous technological developments, AM expands in versatility and different material usage capabilities. Recently new energy sources have been developed for AM – green wavelength lasers, which provide better energy absorption for pure copper. Due to high thermal and electrical conductivity of copper, this novel AM technology is highly promising for various industries, particularly, there is a huge interest to use it for accelerator applications. In particular, these AM produced accelerator components should reach the associated Ultra High Vacuum (UHV) requirements. In this study, vacuum membranes of pure copper were produced by AM using a green laser source, in different thicknesses and built angles. Furthermore, a vacuum membrane helium leak tightness test was performed at room temperature by using a high-sensitivity mass spectrometer. Comparison of these test results was performed with previously established results. Through this study, novel knowledge and initial results are provided for green laser source AM technology usage for applications for UHV accelerator components

Combination schemes for turning point prediction

We propose new forecast combination schemes for predicting turning points of business cycles. The combination schemes deal with the forecasting performance of a given set of models and possibly providing better turning point predictions. We consider turning point predictions generated by autoregressive (AR) and Markov-Switching AR models, which are commonly used for business cycle analysis. In order to account for parameter uncertainty we consider a Bayesian approach to both estimation and prediction and compare, in terms of statistical accuracy, the individual models and the combined turning point predictions for the United States and Euro area business cycles

Efeito do alumínio sobre a absorção, o acúmulo e o fracionamento do fósforo em sorgo

O trabalho teve como objetivo estudar o efeito do Al sobre a absorção, o acúmulo e o fracionamento do P em duas cultivares de sorgo. As plantas foram expostas a níveis tóxicos de Al durante dez dias e, então, colhidas e determinados o crescimento em tamanho e produção de massa seca, os teores de Al e de P total e as diversas formas de P nas duas partes das plantas. Avaliou-se, também, o efeito do Al sobre a absorção de P pelas raízes de plantas intactas. O Al reduziu o crescimento da raiz seminal e a produção de matéria seca de raízes e parte aérea nas duas cultivares, especialmente na sensível. Os teores de Al e de P total aumentaram nas raízes, mas não foram modificados na parte aérea nas duas cultivares. A absorção de P, entretanto, decresceu na presença de Al nas duas cultivares, principalmente na sensível. O Al, de modo geral, modificou as concentrações das várias formas de P solúvel (Pi e Porg) e insolúvel (P RNA e Presidual), exceto a da forma P LIP. Algumas dessas modificações parecem ser importantes e podem estar relacionadas com o mecanismo de tolerância ao Al em sorgo.The objective of this work was to evaluate Al effect on uptake, accumulation and fractionation of P in two sorghum cultivars. Plants were treated with toxic levels of Al during ten days and then they were harvested and growth, dry matter yield, Al and total P contents and concentrations of the various P forms in the two parts of the plants were determined. Aluminum effect on P uptake was also evaluated in intact plants. Aluminum reduced the growth of the seminal root and dry matter yield in roots and tops of both cultivars, especially in the sensitive one. Aluminum and P contents increased in roots but did not change in the top of both cultivars. Phosphate uptake by roots, however, decreased in the presence of Al in both cultivars, especially in the sensitive one. Aluminum, in general, changed concentrations of all soluble (Pi e Porg) and insoluble P forms (P RNA e Presidual), except of the P LIP form. Some of these modifications seem to be important and may be related to Al tolerance mechanism in sorghum

Hospital and after: experience of patients and carers in rural and remote North Queensland, Australia

This article reports a study of patients and carers discharged from the Townsville General Hospital into rural and remote communities in north Queensland, Australia. The findings indicate the importance of focussing on the experiences of patients and carers in attempting to understand the impact of discharge procedures