Report on the CCT Supplementary comparison S2 on thermal conductivity measurements of insulating materials by guarded hot plate.

Seven National Metrology Institutes (NMIs) from France, United States, United Kingdom, Russia, Mexico, China and Germany participated in an inter-laboratory comparison on thermal conductivity measurements by the Guarded Hot Plate method. This action was part of a series of supplementary inter-laboratory comparisons (including infrared spectral emittance and thermal diffusivity) sponsored by the Consultative Committee on Thermometry (CCT) Task Group on Thermophysical Quantities (TG-ThQ). The objective of this collaborative work was to strengthen the consistency of thermal conductivity measurements carried out worldwide on low conductive materials. Measurements were conducted successively by all participants on the same sets of specimens of insulating materials (mineral wool and expanded polystyrene) at temperatures ranging from 10 °C to 40 °C, according to the International Standard ISO 8302. This protocol aimed to minimize issues of material variability by circulating the same pairs of specimens among the laboratories following the strict format of a round-robin test program. More than 120 data points (combinations of material, thickness and temperature) were compared. 92 % of the data points were in agreement, with differences to weighted mean values less than the expanded uncertainties calculated from the individual NMI uncertainties and uncertainties related to the comparison process.

Gallstone prevalence in relation to smoking, alcohol, coffee consumption, and nutrition. The Ulm Gallstone Study.

BACKGROUND: Besides considering well-known risk factors for the development of gallbladder stones, such as age, sex, fecundity, and hereditary predisposition, efforts at prevention have focused increasingly on other factors, such as nicotine, alcohol, and caffeine consumption, as well as general nutrition, which may be modified. METHODS: A total of 1116 blood donors were examined between April 1994 and February 1995 in the central blood bank of the German Red Cross in Ulm, Germany. Each subject received a questionnaire and underwent to an upper abdominal ultrasound examination. RESULTS: Gallbladder stone disease (current cholecystolithiasis and history of cholecystectomy) was detailed in 5.8% of the men and 6.3% of the women. Neither regularity nor number of daily meals correlated with the frequency of gallstone disease. Vegetarians (n = 48), as a group, were not found to have gallstones. In relation to the consumption of alcohol, tobacco, or caffeine higher prevalence of cholecystolithiasis was found only in heavy drinkers of coffee (P = 0.051; odds ratio (OR), 1.083; 95% confidence interval (CI), 0.999, 1.174). CONCLUSION: Results of the present study do not show a definite relationship between nutritional factors and the consumption of alcohol, tobacco, or caffeine and an increased prevalence of gallbladder stone disease.

Depolarization-induced effects of Ca2+-calmodulin-dependent protein kinase injection, in vivo, in single neurons of cat motor cortex.

Intracellular injection of calcium-calmodulin-dependent protein kinase followed by depolarization and depolarization-elicited impulse activity increased input resistance of neurons of the motor cortex of cats. Protein kinase alone or depolarization in the absence of protein kinase did not produce this effect. An analogous increase of input resistance can be produced in the type B photoreceptor of Hermissenda by applying protein kinase and sufficient depolarization to increase calcium conductance and internal Ca2+ concentration. Given previous studies linking changes in both types of neurons to the development of conditioning, the results suggest the possibility of shared biochemical steps in mechanisms of neuronal adaptation by vertebrate and invertebrate species.