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Early December (early + december)
Selected AbstractsEffect of dietary ,-tocopherol + ascorbic acid, selenium, and iron on oxidative stress in sub-yearling Chinook salmon (Oncorhynchus tshawytscha Walbaum)JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1 2009T. L. Welker Summary A three-variable central composite design coupled with surface-response analysis was used to examine the effects of dietary ,-tocopherol + ascorbic acid (TOCAA), selenium (Se), and iron (Fe) on indices of oxidative stress in juvenile spring Chinook salmon. Each dietary factor was tested at five levels for a total of fifteen dietary combinations (diets). Oxidative damage in liver and kidney (lipid peroxidation, protein carbonyls) and erythrocytes (erythrocyte resistance to peroxidative lysis, ERPL) was determined after feeding experimental diets for 16 (early December) and 28 (early March) weeks. Only TOCAA influenced oxidative stress in this study, with most measures of oxidative damage decreasing (liver lipid peroxidation in December and March; ERPL in December; liver protein carbonyl in March) with increasing levels of TOCAA. We also observed a TOCAA-stimulated increase in susceptibility of erythrocytes to peroxidative lysis in March at the highest levels of TOCAA. The data suggest that under most circumstances a progressive decrease in oxidative stress occurs as dietary TOCAA increases, but higher TOCAA concentrations can stimulate oxidative damage in some situations. Higher levels of TOCAA in the diet were required in March than in December to achieve comparable levels of protection against oxidative damage, which may have been due to physiological changes associated with the parr-smolt transformation. Erythrocytes appeared to be more sensitive to variation in dietary levels of TOCAA than liver and kidney tissues. Using the March ERPL assay results as a baseline, a TOCAA level of approximately 350,600 mg/kg diet would provide adequate protection against lipid peroxidation under most circumstances in juvenile Chinook salmon. [source] The Health Insurance Reform DebateJOURNAL OF RISK AND INSURANCE, Issue 1 2010Scott E. Harrington This article provides an overview of the U.S. health care reform debate and legislation, with a focus on health insurance. Following a synopsis of the main problems that confront U.S. health care and insurance, it outlines the health care reform bills in the U.S. House and Senate as of early December 2009, including the key provisions for expanding and regulating health insurance, and projections of the proposals' costs, funding, and impact on the number of people with insurance. The article then discusses (1) the potential effects of the mandate that individuals have health insurance in conjunction with proposed premium subsidies and health insurance underwriting and rating restrictions, (2) the proposed creation of a public health insurance plan and/or nonprofit cooperatives, and (3) provisions that would modify permissible grounds for health policy rescission and repeal the limited antitrust exemption for health and medical liability insurance. It concludes by contrasting the reform bills with market-oriented proposals and with brief perspective on future developments. [source] Sustained, Natural Spawning of Southern Flounder Paralichthys lethostigma Under an Extended Photothermal RegimeJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2001Wade O. Watanabe Hormone-induced spawning of southern flounder Paralichthys lethostigma has produced substantial numbers of viable eggs, but wide variations in fertilization and hatch rates have been reported. Recently, sustained natural spawning of southern flounder broodstock, without hormone induction, has been achieved in our laboratory. Adults (average weight = 1.12 kg; N= 25), including 6 captured as juveniles in 1993 and 19 captured as adults during September 1998, were stocked in two 4.8-m3 controlled-environment tanks in October 1998 and held under natural photothermal conditions until January 1999, when an artificial winter photo-period of 10 L:14 D was initiated and then maintained through April 1999. Sex ratio was approximately 13 females:8 males:7 unknown. Natural spawning was observed in early December 1998 and increased in frequency to a peak in March 1999, before declining in late April. Water temperature ranged from 13.9 to 24.5 C during the spawning period. Natural spawnings over 142 d produced a total of 18.3 × 106 eggs, with a mean fertilization rate of 28.0% (range = 0,100%), yielding 4.94 × 106 fertilized eggs. The mean percentage of eggs that remained buoyant in full-strength seawater (34 ppt) was 41.3% (0,98%), while hatching rate of buoyant eggs was 37.3% (0,99%) and survival of yolksac larvae to the first-feeding stage was 30.2% (0,100%). Gonadal biopsies in late April identified six females from both tanks as probable spawners. A preliminary comparison suggests that natural spawning produced much larger numbers of viable eggs per female, with higher egg quality (i.e., fertilization and hatching success) than hormone-induced spawning. In contrast to natural spawning, hormone-induced strip-spawning enabled timing of spawnings to be more precisely controlled. These results suggest that a combination of both natural and hormone-induced spawning of photothermally conditioned fish will help produce the large numbers of eggs required to support commercial production. [source] The Six-Party Talks and North Korea's Denuclearization: Evaluation and ProspectsPACIFIC FOCUS, Issue 2 2010Tae-Hwan Kwak The six-party process for North Korea's denuclearization has long been stalled since the Six-Party Talks (SPT) failed to agree on a verification protocol in early December 2008. The DPRK officially stated on 10 February 2005 that it already possessed nuclear weapons. It now wants to be recognized as a nuclear power. The North Korean nuclear issue, a key obstacle to the Korean peace process, needs to be resolved peacefully through the six-party process. The author has argued over the years that while the six-party process is the best means to resolve the North's nuclear issue, bilateral US,DPRK talks are equally important to a peaceful and diplomatic resolution of the DPRK's issue. The peaceful resolution of the North's nuclear issue is prerequisite to building a peace regime on the Korean peninsula and regional peace in Northeast Asia. The author has two specific goals: (i) to evaluate the stalled SPT for denuclearizing the Korean peninsula since December 2008; and (ii) to make policy recommendations for continued denuclearization of the Korean peninsula in the framework of the SPT. The first part of this article examines DPRK's denuclearization process up to the point when the SPT failed to adopt a written verification protocol in December 2008. Since then, the six-party process has been stalled. The second part discusses the impact of the DPRK's rocket launch in April 2009 and its second nuclear test in May on the SPT. The third part evaluates the DPRK's new proposal for peace treaty talks and its new conditions for returning to the SPT. Finally, this article proposes key issues on agenda to be negotiated at the next SPT and some policy recommendations for achieving denuclearization of the Korean peninsula. [source] Reproductive Biology of the Epiphytic Bromeliad Werauhia gladioliflora in a Premontane Tropical ForestPLANT BIOLOGY, Issue 2 2005A. Cascante-Marín Abstract: The floral phenology, fruit and seed production, and self-compatibility of Werauhia gladioliflora, an epiphytic bromeliad with a wide distribution, were studied in a premontane forest in the Monteverde area in Costa Rica. The species presents the pollination syndrome of chiropterophily, and it is visited by the small bats Hylonycteris underwoodi and Glossophaga commissarisi (Glossophaginae). The population flowering period extended from October to early December (end of rainy season) and seed dispersal occurred from February to April (dry season). Most plants opened a single flower per night, either every day or at one-day intervals during the flowering period. In natural conditions, the average fruit set amounted to almost half of the potential output, but individual fecundity (number of seeds) remained high. Seed number per fruit and germination capacity after artificial selfing and out-crossing treatments did not differ from natural pollination conditions. Werauhia gladioliflora exhibited high levels of autonomous self-pollination and self-compatibility at the individual and population level, characters associated with the epiphytic habitat. These reproductive traits are also associated with early colonizer species, yet life history traits, such as seed dispersal, seedling establishment success, and growth, are likely to have a major role in determining the presence of this species in the successional vegetation patches scattered over the studied premontane area. [source] | ||||||||||