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Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. In support of this development and an associated license application to the U.S. Nuclear Regulatory Commission (NRC), the DOE completed an extensive performance assessment (PA) for the proposed YM repository in 2008. This presentation describes the assessment of compliance with ground water protection standards in the 2008 YM PA. The following topics are addressed: (i) regulatory background, (ii) analysis structure including characterization of uncertainty, and (iii) analysis results for each of the ground water protection standards. The present article is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional articles in the issue describe other aspects of the 2008 YM PA.

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. In support of this development and an associated license application to the U.S. Nuclear Regulatory Commission (NRC), the DOE completed an extensive performance assessment (PA) for the proposed YM repository in 2008. This presentation describes uncertainty and sensitivity analysis results for the igneous intrusive scenario class and the igneous eruptive scenario class obtained in the 2008 YM PA. The following topics are addressed for the igneous intrusive scenario class: (i) engineered barrier system conditions, (ii) release results for the engineered barrier system, unsaturated zone, and saturated zone, (iii) dose to the reasonably maximally exposed individual (RMEI) specified in the NRC regulations for the YM repository, and (iv) expected dose to the RMEI. In addition, expected dose to the RMEI for the igneous eruptive scenario class is also considered. The present article is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional articles in the issue describe other aspects of the 2008 YM PA.

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. In support of this development and an associated license application to the U.S. Nuclear Regulatory Commission (NRC), the DOE completed an extensive performance assessment (PA) for the proposed YM repository in 2008. The conceptual structure and organization of the 2008 YM PA is based on decomposing the analysis into the following scenario classes: nominal, early waste package failure, early drip shield failure, igneous intrusive, igneous eruptive, seismic ground motion, and seismic fault displacement. This presentation describes how results obtained for the individual scenario classes are brought together in the determination of expected dose to the reasonably maximally exposed individual (RMEI) specified by the NRC in the regulatory requirements for the YM repository and presents associated uncertainty and sensitivity analysis results. The following topics are addressed: (i) determination of expected dose to the RMEI from all scenario classes, (ii) expected dose and uncertainty in expected dose to the RMEI for 0 to 20,000 yr, (iii) expected dose and uncertainty in expected dose to the RMEI from for 0 to 10 6 yr, (iv) justification for the decomposition procedure used to estimate expected dose to the RMEI from all scenario classes, and (v) effectiveness of individual barrier systems in reducing releases from the repository and thus dose to the RMEI. The present article is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional articles in the issue describe other aspects of the 2008 YM PA.

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. In support of this development and an associated license application to the U.S. Nuclear Regulatory Commission (NRC), the DOE completed an extensive performance assessment (PA) for the proposed YM repository in 2008. This presentation describes uncertainty and sensitivity analysis results for the nominal scenario class (i.e., for undisturbed conditions) obtained in the 2008 YM PA. The following topics are addressed: (i) uncertainty and sensitivity analysis procedures, (ii) drip shield and waste package failure, (iii) engineered barrier system conditions, (iv) radionuclide release results for the engineered barrier system, unsaturated zone, and saturated zone, and (v) dose to the reasonably maximally exposed individual specified in the NRC regulations for the YM repository. The present article is part of a special issue of Reliability Engineering and System Safety devoted to the 2008 YM PA; additional articles in the issue describe other aspects of the 2008 YM PA.

The effects of geographic location and production light level on vegetative growth and flowering were evaluated as a means of accelerating the development of tree-form crapemyrtles. By the end of the first year of the experiment, Dynamite™, ‘Muskogee’, ‘Natchez’, and ‘Tuscarora’ grown in Oregon were as much as 42, 51, 43, and 92% taller, respectively, than plants in Alabama, while plants generally had less trunk diameter in Oregon. ‘Muskogee’ and ‘Natchez’ in both locations and ‘Tuscarora’ in Alabama were generally taller when grown under 50% shade than plants in full sun, while height of Dynamite™ was not affected by production light level. Trunk diameter of ‘Natchez’ in both locations and of Dynamite™ in Alabama was less when plants were grown under shade, while trunk diameter of ‘Muskogee’ and ‘Tuscarora’ was not affected by production light level. Flowering of plants grown under shade in Alabama was delayed, while no plants in Oregon flowered the first year. In the second year of the experiment when all plants were grown in full sun, all cultivars continued to be taller in Oregon, while trunk diameter remained greater in Alabama. The height advantage gained from growing plants under shade the previous year was not evident in any cultivar by the end of the second year, while trunk diameter was similar for all cultivars previously grown in full sun and under 50% shade. There was no difference in flowering of plants in Alabama previously grown under 50% shade and in full sun, while 50 to 100% of the four cultivars in Oregon flowered with no obvious difference due to prior production light level.

The effects of production light level on growth of crapemyrtle were evaluated as a means of accelerating the development of tree-form crapemyrtles (Lagerstroemia spp.). By the end of the first growing season, plant height and shoot length of ‘Fantasy’ and ‘Tuscarora’ were greater when grown under 50 or 80% shade than when grown in full sun. By the end of the second growing season, height and shoot length of all three cultivars grown under one or both shade levels were greater than those of plants grown in full sun. In a second experiment, ‘Carolina Beauty’ and ‘Tuscarora’, but not Dynamite™, were taller at the end of the first growing season when grown under 50 or 80% shade than when grown in full sun. Flowering of all cultivars grown under shade was suppressed or delayed. Caliper of Dynamite™ and ‘Tuscarora’ at the end of the first growing season was greatest when grown in full sun, while production light level had no effect on caliper of ‘Carolina Beauty’. At the end of the second season, during which all plants were grown in full sun, there were no height, caliper, or flowering differences of any cultivar due to previous production light level, except for less caliper growth of ‘Tuscarora’ previously under 80% shade compared to plants grown in full sun.

Tree shelters were evaluated as a means of accelerating height growth of tree-form crapemyrtles. In two experiments, Dynamite™ grown in shelters were 124 and 48% taller at the end of the growing season, while shelter-grown ‘Potomac’ were 61 and 50% taller. Height of ‘Tuscarora’ was not affected by tree shelters. In the first experiment calipers of sheltered and non-sheltered ‘Tuscarora’ and Dynamite™ were similar at the end of the season, while caliper of ‘Potomac’ was 35% less when grown in shelters. In the second experiment there were no caliper differences between sheltered and unsheltered Dynamite™ or ‘Potomac’ at the end of the growing season. All plants grown in tree shelters flowered later than unsheltered plants and had visibly straighter, more upright trunks with minimal lateral shoot development.

The effects of production light level on coppicing and coppice timing were evaluated as means of accelerating the development of tree-form crapemyrtles. By the end of the growing season, ‘Fantasy’ and ‘Tuscarora’ coppiced in March and grown under 80% shade were 23 and 18% taller, respectively, than coppiced plants in full sun, but similar in height to plants under 50% shade. Coppiced Dynamite™ under 80% shade and coppiced ‘Carolina Beauty’ under 50% shade were 11 and 26% taller than coppiced plants in full sun, respectively, by the end of the growing season. Height of ‘Fantasy’ and ‘Tuscarora’, but not ‘Natchez’, at the end of the growing season decreased as coppicing was delayed from January to June. ‘Natchez’ coppiced in March were taller than plants coppiced in January or February and 68% taller than plants coppiced in June by the end of the growing season. Cross-sectional stem area of coppiced Dynamite™ and ‘Fantasy’ grown in full sun was greater than that of plants under 50 or 80% shade. Stem area of coppiced ‘Tuscarora’ under 50% shade was greater than that under 80% shade, but similar to that of coppiced plants in full sun. Stem area of coppiced ‘Carolina Beauty’ was greatest when grown in full sun, followed by growth under 50% shade, and least in plants grown under 80% shade. Stem area of ‘Fantasy’, ‘Natchez’, and ‘Tuscarora’ at the end of the growing season decreased linearly as coppicing was delayed from January to June. Visually, coppiced plants had straighter shoots, more uniform shoot diameters, and less branching off the main trunks than non-coppiced plants.

Progesterone, through its nuclear receptors (PR), regulates the development and growth of breast cancers. PR also serve as markers of hormone dependence and prognosis in patients with this disease, and functional PR are required to mediate the antiproliferative effects of progestin therapies. We find that normal and malignant breast cells and tissues can express anomalous forms of PR transcripts. We have isolated four variant PR mRNAs that contain precise deletions of exons encoding sections of the DNA- and hormone-binding domains. The transcripts lack exon 2 (PRdelta2), exon 4 (PRdelta4), exon 6 (PRdelta6), or exons 5 and 6 (PRdelta5,6). On immunoblots, PRdelta4, delta6. and delta5, 6 cloned into the background of the PR A-isoform comigrate with similar proteins present in breast tumor extracts; delta6 and delta5, 6 are dominant-negative transcriptional inhibitors of wild-type A- and B-receptors. We propose that expression of variant PR can compromise the accuracy of receptor measurements as markers of hormone-dependent cancers, and can modify the responses of tumors to progestin therapies.

In this ongoing research study the independent and interactive effects of dietary fat and calories on a putative intermediate marker of cancer risk, oxidative DMA damage, are being examined. Subjects are healthy women between the ages of 25 and 50, with no history of cancer and not receiving hormone therapy. Subjects are being randomized to one of 4 dietary plans: control, low-fat (LF), low-calorie (LC), and low-calorie/low-fat (LCLF). The LF 4 LCLF diets are a modified version of the Low-Fat Eating Plan developed by the University of Minnesota and limit fat intake to 15% of total calories. Except for the control group, all the diets utilize ADA Lists for Meal Planning to assist participants in monitoring their caloric intakes and achieving caloric goals. The goal for the LF diet is to maintain baseline caloric intake. The goal for the LC and LFLC diets is a 25% reduction in caloric intake. Subjects meet with a registered dietitian bi-weekly, and keep daily food records for 12 weeks. Thus far, 17 subjects have completed the study and eventually 120 women will be studied. Preliminary data indicate good compliance. The LF group of women went from 36% of calories from fat at baseline to 17% at study's ,end with largely no change in caloric intake. The LC group decreased caloric intake by 36% but kept % calories from fat relatively constant. The LCLF group decreased caloric intake by 31% and decreased fat to 19% of calories. The control group kept both calories and fat at usual levels. These data indicate it is possible to selectively manipulate dietary fat and/or calories over a 12-week period, which makes research on the relative effects of these nutrients on biomarkers of cancer risk feasible in humans. This study is supported by grant CA60812 from the NCI.