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Reactive sputtering is a very useful technique, particularly, for producing inhomogeneous interference filters, where the refractive index changes smoothly during deposition. In such a context, precise control of deposition parameters is crucial for replicating the desired optical properties. This study employed a pulsed DC power source to investigate the influence of a duty cycle on target poisoning, sputtering plasma characteristics, electric signals, and optical and morphological properties of synthesized films. Reactive pulsed DC magnetron sputtering was characterized by analyzing the behavior of plasma emission via optical emission spectroscopy and voltage-current signals, while modulating parameters such as the oxygen content within the vacuum chamber. A set of thin films was coated on glass substrates under different system conditions. These films underwent characterization employing spectroscopic ellipsometry to ascertain their optical constants, atomic force microscopy for surface morphology analysis, and x-ray diffraction for the determination of crystalline structures. The results indicate that longer duty cycles required higher oxygen levels to poison the target. Additionally, a detailed analysis of electrical signals revealed nonsquare waveforms, whose characteristics were influenced by both the duty cycle and the oxygen content within the sputtering chamber, resulting in higher effective voltages during the on-time of the voltage pulse. Grown films via reactive pulsed DC magnetron sputtering were also compared to films grown via conventional DC magnetron sputtering at equivalent conditions of target poisoning. [ABSTRACT FROM AUTHOR]

At the onset of egg production, physiological changes governing calcium and phosphorus utilization must occur to meet demands for medullary bone formation and eggshell mineralization. The objective of this study was to identify these changes and determine if they are influenced by dietary supplementation with 1α-hydroxycholecalciferol (AlphaD3™, Iluma Alliance). Commercial laying hens fed either a control or AlphaD3-supplemented diet beginning at 18 weeks of age were sampled at 18 (n = 8) and 31 weeks (n = 8/diet) to evaluate mRNA expression associated with calcium and phosphorus utilization in kidney, shell gland, ileum, and liver, circulating vitamin D3 metabolites, and bone quality parameters in humerus, tibia, and keel bone. Though diet did not heavily influence gene expression at 31 weeks, several significant differences were observed between 18- and 31-week-old hens. Heightened sensitivity to hormones regulating calcium and phosphorus homeostasis was observed at 31 weeks, indicated by increased parathyroid hormone receptor 1, calcium-sensing receptor, calcitonin receptor, and fibroblast growth factor 23 receptors in several tissues. Increased renal expression of 25-hydroxylase and vitamin D binding protein ( DBP ) at 31 weeks suggests kidney participates in local vitamin D3 25-hydroxylation and DBP synthesis after egg production begins. Biologically active 1,25(OH)2D3 was higher at 31 weeks, with correspondingly lower inactive 24,25(OH)2D3. Increased expression of plasma membrane calcium ATPase 1 and calbindin in kidney, shell gland, and ileum suggests these are key facilitators of calcium uptake. Elevated renal inorganic phosphorus transporter 1 and 2 and sodium-dependent phosphate transporter IIa at 31 weeks suggests increased phosphorus excretion following hyperphosphatemia due to bone breakdown for eggshell formation. Diet did influence bone quality parameters. Bone mineral density in both humerus and tibia was higher in AlphaD3-supplemented hens at 31 weeks. Tibial bone mineral content increased between 18 and 31 weeks, with AlphaD3-supplemented hens increasing more than control hens. Moreover, control hens exhibited diminished tibial breaking strength at 31 weeks compared to hens at 18 weeks, while AlphaD3-supplemented hens did not. Together, these results indicate supplementation with AlphaD3 enhanced bone mineralization during the medullary bone formation period and elucidate the adaptive pathways regulating calcium and phosphorus utilization after the onset of lay. [ABSTRACT FROM AUTHOR]

Objective: To estimate the long-term and short-term effects on cigarette demand in Argentina based on changes in cigarette price and income per person >14 years old.

OBJECTIVE: To evaluate the processes and outcomes of tobacco litigation in Argentina and to analyse the strategies of the tobacco industry to oppose litigation using tobacco industry documents. METHODS: A systematic search of tobacco industry documents on the internet dating from 1978 to 2002. Law library searches using Argentinean official and unofficial reports systems were combined with computerised online searches. RESULTS: There have been at least 15 failed litigation cases in Argentina and the tobacco industry presented a concerted defence in every claim regardless of cost. We categorised 11 cases as product liability and nicotine addiction, two as health care reimbursement, and two as criminal law and secondhand smoke. Industry strategies included hiring legal consultants from prestigious international and Argentinean law firms and developing litigation prevention programmes. Industry monitored legal academic meetings, controlled the development of new product liability legislation, obtained favourable opinions from experts, and closely observed the development of litigation in Argentina. CONCLUSION: The strategies used by the industry have been successful in preventing recovery for tobacco injuries through litigation. Argentinean health advocates and lawyers need to be aware of the roles and strategies of the tobacco industry in order to develop effective litigation in Argentina.

In this article, the authors use recently collected data from the "Educatodos" program in Honduras to analyze attrition, an outcome that has received little attention in previous analyses of alternative school effectiveness. "Educatodos" began in the 1990s with radio courses in primary grades mainly for rural adults. Through the years the program has generated more than 350,000 person-years of education. Since 2001 it has also provided middle schooling through audiotape lessons delivered in local learning centers, and its rural focus on adults has given way to a more diverse profile that includes recent graduates of public primary schools. "Educatodos" is a good example of a complementary provider of education, although it does rely on a different teaching technology compared with the average public middle school. The central challenge facing the program is clear, however: to keep costs low enough to encourage participation among the poorest sectors of society and quality high enough to maintain enrollments. The steady growth in learning centers offering these grades suggests that the program is meeting this dual challenge. The overall impact of this expansion, however, has been tempered by evidence of high rates of attrition. It would be easy to attribute attrition in a program such as "Educatodos" to contextual forces related to poverty, but their data show that completion rates are not uniformly low in the program, even among the poorest participants. This suggests that specific features of program implementation affect continuation, a proposition that makes intuitive sense but is based on little empirical evidence in developing-country settings. (Contains 4 tables and 13 footnotes.)

The impact of attrition on Educatodos, an example of a complementary provider of education for middle schooling through audiotape lessens delivered in local learning centers is assessed. While there has been an increase in the number of learning centers offering this program, the overall impact of this expansion has to a certain extent been nullified by high rates of attrition which is a challenge that needs to be tackled in delivering real change in poor communities.