Nonlinear static and dynamic analysis of circular plates and shallow spherical shells using the collocation method

The present work investigates the efficacy and applicability of interior global orthogonal point collocation method to the axisymmetric nonlinear analysis of elastic circular plates and shallow spherical shells subjected to uniformly distributed transverse load. Spacewise discretisation has been carried out using a polynomial expansion with the zeros of a Chebyshev polynomial as collocation points. Timewise integration has been carried out with Newmark k-β scheme corresponding to average acceleration method. The static response and snap-through buckling results, as well as, the dynamic response and dynamic buckling results under a uniformly distributed step load have been obtained and found to agree closely with the available results.     

Hepatitis B virus infection, hepatitis B vaccine, and hepatitis B immune globulin

Hepatitis B virus (HBV) infection is a major health problem in the United States; in 1995, approximately 128,000 cases occurred. Transmission of HBV occurs primarily by blood exchange (eg, by shared needles during injection drug use) and by sexual contact. Persons infected early in life are much more likely to become chronically infected than those infected during adulthood: as many as 90% of infants infected perinatally develop chronic infection and up to 25% will die of HBV-related chronic liver disease as adults. Clinical signs of acute hepatitis occur in about 50% of infected adults but in only 5% of infected preschool-aged children. In the United States, hepatitis B vaccine is currently made by recombinant DNA technology using baker's yeast. Preexposure vaccination results in protective antibody levels in almost all infants and children (> 95%) and healthy adults younger than 40 years of age (> 90%). The most common adverse event following administration of hepatitis B vaccine is pain at the injection site, which occurs in 13% to 29% of adult and 3% to 9% of children. A comprehensive hepatitis B vaccination policy is now recommended that includes (1) routine infant vaccination; (2) catch-up vaccination of 11- to 12-year-olds who were not previously vaccinated; (3) catch-up vaccination of young children at high risk for infection; (4) vaccination of adolescents and adults based on lifestyle or environmental, medical, and occupational situations that place them at risk; and (5) prevention of perinatal HBV infection.     

Cortisone-induced osteoporosis: effects on bone adenylate cyclase

The majority of patients with soft tissue or bone sarcomas of the upper extremity can be treated today with limb-saving procedures using combined modality therapies. For patients with a tumor in the shoulder area, sometimes an interscapulothoracic amputation is the only radical surgical treatment. However, in selected cases, in which the tumor does not involve the neurovascular bundle, a limb-sparing alternative might be the Tikhoff-Linberg resection. Normal function of the hand and forearm, with reasonable function of the elbow, can be maintained by this procedure. Four case histories are reported.     

Biparietal diameter: a useful measure for determining gestational age of human abortuses

BACKGROUND: The crown-rump length is conventionally used to determine the age of human abortuses. However, it is not reliable as it is dependent on the positioning of the conceptus. We compared this with the biparietal diameter and foot length for determining the gestational age. METHODS: Different measurements, commonly used to assess gestational age, were measured in 146 human abortuses for which an accurate obstetric history could not be elicited. Measurements taken were crown-rump length, biparietal diameter and foot length. These were correlated with the observations at antenatal examinations before finalizing the approximate age. RESULTS: Multiple regression analysis of the data indicated that of the three measurements, the biparietal diameter was the most reliable for determining foetal gestational age between 8 and 26 weeks. The age determined with the biparietal diameter correlated well with that of abortuses with an accurate obstetric history. CONCLUSION: The biparietal diameter of a human foetus may be used to determine its age if the obstetric history regarding the period of gestation is vague or not available.     

Maternal and neonatal outcomes after prolonged latent phase

Glycol ethers such as 2-ethoxyethanol (EE) are widely used as solvents because they are miscible in aqueous and organic solutions. Toxic effects of EE in rodents include teratogenicity, fetotoxicity, hematotoxicity, and testicular atrophy. The purpose of this study was to determine the effect of dose on the absorption, metabolism, and excretion of 2-ethoxy [U-14C]ethanol by F344/N rats after inhalation exposure. Rats were exposed to either 5 ppm EE for 5 hr 40 min or 46 ppm EE for 6 hr. The uptake and metabolism of EE were linear in the concentration range studied. Significant percentages of the retained doses were exhaled during (22%) and after exposure (16%) as 14CO2. Forty-six percent of the retained dose was excreted in the urine. Approximately 10% of the retained dose was detected in the carcass 66 hr after exposure. The major urinary metabolite was ethoxyacetic acid (EAA), the toxic metabolite of EE. The amount of EAA excreted was linearly related to exposure concentration. Ethylene glycol and N-ethoxyacetyl glycinate were identified as minor metabolites excreted in the urine. The results of this study suggest that the toxicity of inhaled EE should be directly proportional to the exposure concentration up to 46 ppm if the toxicity of EE is due to EAA.