Development of high speed power thyristor: The gate assisted turn-off thyristor

A high speed power switch with unique turn-off capability was developed. This gate-assisted turn-off thyristor was rated at 609 V and 50 A with turn-off times of 2 microsec. Twenty-two units were delivered for evaluation in a series inverter circuit. In addition, test circuits designed to relate to the series inverter application were built and demonstrated

Midterm Elections Used to Gauge President\u27s Reelection Chances

Since 1952 there have been thirteen instances in which the incumbent president\u27s party lost seats in the House of Representatives in a midterm election. Researchers have created two competing theories to explain this trend. The surge-and-decline theory argues that the reasons for causing high voter turnout in a presidential election are absent in a midterm election, leading to a decline in voter turnout and subsequent losses by the president\u27s party. The other theory, the referendum theory, argues that losses suffered by the president\u27s party are due to the president\u27s performance and the performance of the economy. When it comes to presidential elections, out of the thirteen midterm election losses, the incumbent party was able to retain the White House in the subsequent presidential election six times. The other six times, the incumbent party lost the White House. However, there is little to no research explaining why this is the case. This article attempts to answer two questions. First, can results of midterm elections serve as an indicator of gauging a president\u27s reelection chances? Second, if so, which theory, surge-and-decline or referendum, helps explain this trend this best? Utilizing statistical analysis, my research shows that there is insufficient evidence to conclude whether midterm elections can serve as an indicator of gauging a president\u27s reelection chances

Midterm Elections Used to Gauge President\u27s Reelection Chances

Conventional analysis of midterm elections is usually in relation to the previous presidential election, or the issues or events leading up towards a presidential election. Rarely is midterm elections considered in terms of whether the president, or his party in some cases, would retain the White House in the next presidential election. The focus of this research is to determine whether midterm elections can serve as a predictive indicator of the outcome in the following presidential election. For decades, scholars have speculated as to why the president\u27s party suffers losses at the midterm election. An examination of these theories can provide insight into the variables that should be considered when examining the central question of this research

Aldous Huxley\u27s death concern

In the long course of his restless career, the informed and articulate intellect of Aldous Leonard Huxley has concerned itself with every major aspect of human fortune, but none more intensely than the ultimate experience of death. This constitutes for many his greatest indictment

An Evaluation of exposures to respirable particulates, environmental PM2.5, PAHs and metal compounds in Western Australia

It has been well established that air pollution is associated with health impacts. This study investigated the relationship between exposure to air pollutants and potential biomarkers of health effects. The research project was conducted in 2 separate study locations and cohorts. Study 1: An Evaluation of Children’s Exposures to Respirable Particulates, Environmental PM2.5, PAHs and Metal Compounds in The South West of Western Australia. A cross sectional study to evaluate the exposures of children (n=18), and controls (n=15) to respirable particulates PAHs and metal compounds in the South West of Australia during 2011. Ambient particulate matter (PM2.5) samples were found to be significantly higher in Collie as compared to Dalyellup. However, personal PM2.5 concentrations between locations were not significantly different and both PAH and heavy metals were below the levels of detection. Urinary levels of 1-hydroxypyrene (1-OHpy) were below the level of detection. Copper, selenium and nickel were present in urine samples and these were not significantly different between locations, nor was there any correlation with residential areas within study locations. Urinary nickel concentrations were higher than expected for nonoccupational cohorts and although statistically insignificant, mean values of urinary nickel were highest for homes using gas as a fuel source. These data endorse current views that the reconstruction of PM2.5 exposures and related respiratory health effects based simply on the mass of airborne particulate matter alone is not sufficient in providing an insight to the respiratory health of susceptible subgroups such as children. The presence of certain urinary heavy metals suggests possible accumulation in participants via alternative routes of entry, probably a dietary source. Studies that rely purely on data accrued from ambient PM2.5 mass, and/or general health data might not detect or underestimate significant relationships between certain components of PM2.5. Study 2: Urinary levels of malondialdehyde and 8-deoxyguanosine as biomarkers of oxidative DNA damage induced by exposure to nickel and cobalt in metal refinery workers. Metal mining and refinery workers in Australia have the potential to be occupationally exposed to quantities of heavy metals that may be associated with health impacts affecting major organ and immune systems. Current regulatory and internal company policies and guidelines require regular monitoring of occupational exposures of employees through a combination of air borne sampling as well as biological monitoring for heavy metals. Toxic levels of heavy metals accumulated in the body have been shown to elicit inflammatory responses linked to exacerbated health effects impacting the respiratory, cardiovascular and nervous systems. There are many studies that have established a significant link between heavy metal exposure and increased oxidative stress. In light of these observations, this study investigated urinary levels of nickel (Ni) and cobalt (Co) and Malondialdehyde (MDA) and 8-hydroxy-2’deoxyguanosine (8-OHdG) which are oxidative stress markers indicative of cellular and DNA damage. A positive correlation between urinary Ni and Co exposure and oxidative stress markers among refinery workers was established. This finding has implications for occupational health management as individual responses to exposures can now be identified. In addition to implementing a global mean air borne exposure standard, individual variation and sensitivity can be accommodated through the use of urinary oxidative stress marker

Determinants of farmer adoption of organic production methods in the fresh-market produce sector in California: A logistic regression analysis

This research uses binomial and multinomial logistic regression models to identify the factors that influence farmers adoption of organic technology. Using a sample of 175 farmers growing fresh-market produce in three California counties, the first model examines farmers choice between conventional-only and organic-only production. The second model compares conventional-only and "dual-method" (combined conventional and organic) production, while the third model employs all three choices in a multinomial model. These results, which indicate that gross sales, direct marketing, number of crops and acres, farmer age, and computer usage are significant determinants, have implications on policies that regulate the organic foods sector.Production Economics,

The effectiveness of teamwork training on teamwork behaviors and team performance : A systematic review and meta-analysis of controlled interventions

The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed