Inclusion systems of organic molecules in restacked single-layer molybdenum disulfide.

Novel materials have been obtained by restacking single-layer molybdenum disulfide (MoS(2)) with organic molecules included between the layers. A large variety of organic molecules can be included between layers of MoS(2) and other transition-metal dichalcogenides. The films with the included organics are formed at the interface between an aqueous suspension of the MoS(2) and a water-immiscible organic liquid. The organic molecules are not necessarily electron donors. A highly oriented, conducting film of restacked MoS(2) containing ferrocene is presented as an example.

Ruminant heat stress: effect on production and means of alleviation.

A review of the literature indicates heat stress generally causes lower milk production, decreased growth rate for cattle and lambs, but little effect on wool production. Breed and diet affects the degree of adverse response. Heat stress is caused primarily by high air temperature, but can be intensified by high humidity, thermal radiation and low air movement. Improving performance of animals under warm conditions involves breeding and management and modifying the environment. The former includes selection for heat tolerance, use of crossbred animals, diets with low heat increment in relation to energy for production and control of diseases and parasites. Environmental modifications may include provision of shades, use of water for evaporative cooling and increased air movement.

The effect of cyclic and constant ambient temperatures on feed consumption, egg production, egg weight, and shell thickness of hens.

Groups of 18 hens, 230 days of age, were housed in each of three climatic chambers with light schedules of 14L:10D. One was maintained at a constant temperature of 23.9 C, the second was cycled between 15.6 and 37.7 C (mean, 26.7 C), and the third was cycled between 21.1 and 37.7 C (mean, 29.4 C). In Experiment 1, the high temperature peaked during the dark period at 0200 hr and in Experiment 2, the high temperature peak was at 1400 hr during the light period. The birds had free access to a commercial breeder feed in these two experiments. The results from three 2-week observation periods indicated no significant differences in percent hen-day production, grams of feed per gram of egg mass, or overall body weight change but feed intake per day, egg weight, and shell thickness were significantly reduced by mean temperatures of 26.7 and 29.4 C in cycling chambers. The pair-feeding of birds in the 23.9 C constant chamber compared with those in the cycling 29.4 C chamber resulted in production of significantly heavier eggs with thicker shells without significantly influencing any of the other parameters. The reductions in egg weight and shell thickness observed at cyclic temperatures were not simply a result of a reduction in nutrient intake at high temperatures but also the direct effect of heat stress on the hens. In the 23.9 C constant temperature chambers, a reduction in AME of the feed for the hens fed ad libitum was observed but not for hens pair-fed to hens in the 29.4 C cyclic chamber.

Guglielmi detachable coils: an alternative therapy for surgically high-risk aneurysms.

In September 1995, the Guglielmi Detachable Coil (GDC) system received approval from the Food and Drug Administration (FDA) for treatment of surgically high-risk aneurysms. Up until that time, only the centers participating in the clinical device trial were able to offer the GDC system as an option to patients considered to be surgically high-risk and who would otherwise be assigned to conservative treatment. As additional sites become available, neuroscience nurses need to be educated on the device and the type of care necessary for these patients.

On estimating processing variance: commentary and reanalysis of Kail's "Developmental functions for speeds of cognitive processes".

A recent paper by Kail (1988) in this journal appears to contain a significant error in the data analysis. The "goodness-of-fit" coefficients reported which suggest that overall about 94% of the variance can be accounted for by the model seem to be a substantial overestimation as a result of inappropriate procedures for statistical modeling. Using the data made available to us by Kail, we have reanalyzed these results. The corrected values range from 0.9 to 92.1% for the individual tasks with an overall average between 40 and 60%. We suggest that the support for the original conclusions is considerably weaker than reported.

When is a serum iron really a serum iron? The status of serum iron measurements.

Although serum iron determinations play an important role in the diagnostic process, the accuracy of routine methods is suspect. The poor performance of currently used methods is well documented in the quarterly College of American Pathologists survey reports. Compared with the 1990 method of the International Committee for Standardization in Haematology (ICSH), the 1978 ICSH Reference Method shows a +3.4% bias and the standard method of the National Committee for Clinical Laboratory Standards shows a -17.8% bias for iron results. All routine methods checked--DuPont aca, Abbott TDx, Kodak Ektachem (except one lot), BM/Hitachi 717, and Synermed--show a negative bias over the entire analytical range, a significant negative intercept, and extremely poor correlation with the 1990 ICSH method for iron values < 750 micrograms/L. Individual discrepancies of several hundred percent were observed. Imprecision of the methods is not the reason for these discrepancies. We question whether most routine methods measuring low iron concentrations provide results sufficiently reliable for confirmation of iron deficiency.