Vapor Pressure versus Temperature Relations of Common Elements.

The vapor pressure values of common elements are available in the literature over a limited temperature range and the accuracy and reliability of the reported data are not generally available. We evaluate the reliability and uncertainty of the available vapor pressure versus temperature data of fifty common pure elements and recommend vapor pressure versus temperature relations. By synthesizing the vapor pressure values from measurements reported in the literature with the values computed using the Clausius Clapeyron relation beyond the boiling point, we extend the vapor pressure range from 10-8 atm to 10 atm. We use a genetic algorithm to optimize the fitting of the vapor pressure data as a function of temperature over the extended vapor pressure range for each element. The recommended vapor pressure values are compared with the corresponding literature values to examine the reliability of the recommended values.

Preference for place of death in a continuing care retirement community.

PURPOSE: To describe death-related planning and preferences for place of death among well elders in a community characterized by a low rate of hospital deaths. DESIGN AND METHODS: Cross-sectional prevalence survey of independent-living residents (n = 219) of a continuing-care retirement community (CCRC) in Central North Carolina characterized by a low rate of hospital deaths. RESULTS: Death-related planning played a part in the decision of 40% of residents to move to the CCRC. A majority of residents reported a clear preference for place of death, and a majority of these preferred to die on the CCRC campus. Most residents wanted to discuss their preferences for place of death with their health care provider. Preferences for place of death appear consistent across age cohorts and are relevant to elders' long-term care decisions. IMPLICATIONS: Given the striking discrepancy between patients' preferences for nonhospital deaths and the high prevalence of hospital deaths in the United States, this often-neglected issue should be routinely addressed in end-of-life planning. The CCRC may be a practice model that is particularly compatible with personal preferences for place of death.

Anorexia nervosa, bulimia nervosa: causal theories and treatment.

Anorexia nervosa and bulimia nervosa are eating disorders characterized by gross disturbances in eating behavior. Recently these disorders have reached near-epidemic proportions, affecting approximately 1.2 million adolescent and young adult females in the United States. The incidence in males is considerably less, and the prevalence rate has remained fixed at 5 percent during the last five years. The estimates of mortality range between 1 and 15 percent and are equally divided between medical complications (electrolyte disturbance, acute kidney failure, cardiac complications) and suicide. Successful treatment requires a combination of aggressive medical management, psychotherapy, behavioral management, food-intake management and nutritional counseling. This requires health care providers to understand 1) the psychological ramifications of these disorders, 2) the types of depression associated with them, 3) antidepressants used and therapeutic dosages, 4) correction of nutritional deficiencies, 5) outpatient management and 6) indications for hospitalization (inpatient management).

Direct determination of fluoride in aluminium reduction materials by using an ion-selective electrode.

Macro amounts of fluoride in aluminium reduction materials are successfully determined with a fluoride electrode. Except for anhydrous aluminium fluoride, which requires fusion with sodium hydroxide, samples are dissolved in aqueous media. Cryolite and sodium fluorosilicatc are dissolved in boiling sodium hydroxide solution. Other materials containing fluoride, such as fluorspar and the reduction cell bath and pot-lining, require dissolution in a hydrochloric acid solution of aluminium chloride. Potential interference from large amounts of aluminium (and calcium, if present) is eliminated and pH control attained by using ammoniacal sulphosalicylate (and EDTA). The procedures are reasonably rapid. Relative errors of less than 2% and a relative standard deviation of 1% are achieved.