Evolution of Filament-Shaped Porous Structure in Polycarbonate by Stretching under Carbon Dioxide.

We found that a filament-shaped porous structure with periodic distance was obtained in polycarbonate for optical disk grade (OD-PC) film by stretching under compressed carbon dioxide (CO₂). The evolution of the characteristic porous structure was investigated by in situ observation during the stretching under compressed CO₂ and the optical microscopic observation of the stretched specimen. The voids were obtained under high CO₂ pressure as in the case of elevated temperature, suggesting that the evolution of the voids was caused by crazing due to chain disentanglement by accelerated molecular motion owing to the plasticization effect of CO₂.

Volcanic air pollution over the Island of Hawai'i: Emissions, dispersal, and composition. Association with respiratory symptoms and lung function in Hawai'i Island school children.

Background: Kilauea Volcano on the Island of Hawai'i has erupted continuously since 1983, releasing approximately 300-12000metrictons per day of sulfur dioxide (SO2). SO2 interacts with water vapor to produce an acidic haze known locally as "vog". The combination of wind speed and direction, inversion layer height, and local terrain lead to heterogeneous and variable distribution of vog over the island, allowing study of respiratory effects associated with chronic vog exposure.

A steroid metabolizing gene variant in a polyfactorial model improves risk prediction in a high incidence breast cancer population.

Background: We have combined functional gene polymorphisms with clinical factors to improve prediction and understanding of sporadic breast cancer risk, particularly within a high incidence Caucasian population.

Methods: A polyfactorial risk model (PFRM) was built from both clinical data and functional single nucleotide polymorphism (SNP) gene candidates using multivariate logistic regression analysis on data from 5022 US Caucasian females (1671 breast cancer cases, 3351 controls), validated in an independent set of 1193 women (400 cases, 793 controls), and reassessed in a unique high incidence breast cancer population (165 cases, 173 controls) from Marin County, CA.

Results: The optimized PFRM consisted of 22 SNPs (19 genes, 6 regulating steroid metabolism) and 5 clinical risk factors, and its 5-year and lifetime risk prediction performance proved significantly superior (~ 2-fold) over the Gail model (Breast Cancer Risk Assessment Tool, BCRAT), whether assessed by odds (OR) or positive likelihood (PLR) ratios over increasing model risk levels.

Aeroallergen sensitivity in Hawai'i: association with asthma and increased prevalence of sensitivity to indoor allergens since 1966.

Asthma and allergic diseases have increased globally. Earlier studies suggest a history of excess asthma morbidity and mortality in Hawai'i, with high prevalence of sensitization to outdoor aeroallergens among atopic children. This study was undertaken to test the hypotheses that specific allergens are more associated with asthma, and that sensitivity to common aeroallergens has increased in Hawai'i since 1966.

Vitamin D receptor polymorphisms and breast cancer risk in a high-incidence population: a pilot study.

Background: Marin County, CA has very high incidence of breast cancer. Traditional risk factors, such as those included in the Gail model, do not effectively stratify breast cancer in this population. This retrospective case-control pilot study evaluates DNA from volunteers from a previous Marin County breast cancer epidemiology study.