Complex cardiac defect with hypoplastic right ventricle in a fetus with valproate exposure

We describe a fetus with a hypoplastic right ventricle detected by prenatal ultrasound examination. A possible causal relationship with prenatal valproate exposure is discussed. Copyright © 2005 John Wiley & Sons, Ltd.     

An Analysis of the Yearly Changes in Sulfur Concentrations at Various National Parks in the United States, 1980-1996

ABSTRACT

An apparent increasing trend in the summer concentrations of particulate sulfur at Shenandoah (for the time period 1982-1995) and at Great Smoky Mountains (for the time period 1984-1995) has been pointed out by some researchers. Others have suggested that these increasing trends may be an analytical artifact resulting from the switch from the Stacked Filter Units (SFU) measurement system to the IMPROVE (Interagency Monitoring of Protected Visual Environments) measurement system that occurred during the winter of 1987. To obtain a better understanding of the effect of the protocol change, we investigate the changes in the seasonal averages of sulfur concentrations for successive pairs of years for the period 1980-1996 for about 20 national park sites in the United States. For the period 1980-1987, we use sulfur data from the old (SFU) database and for the period 1988-1996, we use the IMPROVE database. Changes from one year to the next similar to that between 1987 and 1988 occurred during other years and seasons suggesting that chance causes alone could perhaps explain it, the degree to which chance could have caused the changes was measured using the permutation test for matched. At the very least, additional information such as side by side readings using SFU and IMPROVE measurement methods, may be needed to better understand any systematic effect in the sulfur measurements that may be ascribable to the protocol change.     

Water and sustainability

This inquiry summarizes global water resources and patterns of use, applies indicators of water sustainability in order to identify areas of water stress, and examines prospects for water sustainability in the list century. A long-range conventional development scenario is introduced based on a vision of the future in which the values, consumption patterns and dynamics of the Western industrial society will be progressively played out on a global scale. The scenario is driven by commonly cited projections of population and economic growth, assumes no major changes in water policy and, following historic trends, incorporates progressive improvements in the efficiency of water use. The scenario helps clarify the constraints of a conventional picture of water development, and provides a useful point of departure for examining alternative long-range scenarios and their implications for water and development policy. In the conventional development scenario, there is growing pressure on water resources, particularly in developing regions. Strategies for beginning a transition to a sustainable water development path are summarized .     

Effects of Temperature and Relative Humidity on Polylactic Acid Plastic Degradation

Three high molecular weight (120,000 to 200,000 g mol^–1) polylactic acid (PLA) plastic films from Chronopol (Ch-I) and Cargill Dow Polymers (GII and Ca-I) were analyzed for their degradation under various temperature and relative humidity (RH) conditions. Two sets of plastic films, each containing 11 samples, were randomly hung in a temperature/humidity-controlled chamber by means of plastic-coated paper clips. The tested conditions were 28, 40, and 55°C at 50 and 100% RH, respectively, and 55°C at 10% RH. The three tested PLA films started to lose their tensile properties when their weight-average molecular weight (M _w) was in the range of 50,000 to 75,000 g mol^–1. The average degradation rate of Ch-I, GII, and Ca-I was 28,931, 27,361, and 63,025 M _w/week, respectively. Hence, GII had a faster degradation rate than Ch-I and Ca-I under all tested conditions. The degradation rate of PLA plastics was enhanced by the increase in temperature and relative humidity. This trend was observed in all three PLA plastics (Ca-I, GII, and Ch-I). Of the three tested films, Ch-I was the first to lose its mechanical properties, whereas Ca-I demonstrated the slowest loss, with mechanical properties under all tested conditions.