Effect of short-term hormone replacement therapy on left ventricular mass and contractile function

This study examined the effects of neonatal cocaine exposure on the rewarding properties of play in a modified T-maze. Animals were artificially reared from postnatal day (PND) 4-9 with drug concentrated in four daily feeds. There were four treatment groups, 40 mg/kg/day cocaine, 20 mg/kg/day cocaine, an artificially reared control and a surgery control. From PND 38-42, subjects were tested with a food reward (EXP 1) or a play reward (EXP 2). No deficits in learning were seen when the reward was food. The 20 mg/kg/day cocaine group, however, showed impaired learning and altered play behavior when the reward was access to a play partner. Neonatal cocaine exposure thus appears to differentially affect learning based on the type of reward presented.     

New Automated Microwave Heating Process for Cooking and Pasteurization of Microwaveable Foods Containing Raw Meats

ABSTRACT: A new microwave heating process was developed for cooking microwaveable foods containing raw meats. A commercially available inverter-based microwave oven was modified for pasteurization of mechanically tenderized beef, inoculated with Escherichia coli O157:H7 (approximately 5 log₁₀ CFU/g) and packaged in a 12-oz CPET tray containing 150-mL de-ionized water. The new microwave heating system was equipped with an infrared sensor and a proportional feedback mechanism to allow temperature controlled microwave heating. A 2-stage heating strategy was adopted to cook the product. In the primary heating stage, the sample surface temperature was increased to an initial temperature set-point (ITSP, 65, 70, 75, or 80 °C). In the secondary heating stage, the heating was continued with a small fraction of microwave power. The effect of ITSP, hold time (0 to 3 min), and sample elevation (0, 0.03, and 0.07 m above turntable) on inactivation of E. coli O157:H7 and background microflora was evaluated. It was observed that only a small number (approximately 1.3 logs) of E. coli O157:H7 and background microflora were inactivated in the primary heating stage. The elevation 0.07 m, which was in the proximity of the geometric center of the metal cavity, was more effective in inactivating both E. coli O157:H7 and background microflora. Substantially more bacteria were inactivated in the secondary heating stage. Complete inactivation of E. coli and background microflora was observed with heating at temperatures above 70 °C for more than 1 min. This study demonstrated a new approach for ensuring the safety of microwaveable products containing raw meats.     

Electronic transport near the surface of indium antimonide films

Surface layer carrier concentrations and mobilities of n-type InSb films were separated from those of the bulk of the film through the magnetic field dependence of the Hall coefficient coupled with conventional galvanomagnetic measurements. This technique yields a surface electron density for the top plus bottom of the film of (3?5) × 10¹³ cm^?2 and a surface layer mobility of 1500–2000 cm² V^?1 s^?1, both largely independent of temperature. The surface density is found to decrease when the free surface is anodized.     

Consistent low-field picture of bcc3He exchange

Consideration of a physically plausible potential for bcc solid³He suggests that there is significant antiferromagnetic pair exchange between next nearest neighbors and that triple exchange is less important than previously believed. Experimental consequences of such a thesis are consistent with all existing low magnetic field data.     

Man-Made Radio Noise Levels at 150 kHz to 32 MHz Near a Large Antarctic Base

Over recent years increased effort has been applied to scientific research in the Antarctic. This growth has resulted in increased scientific and logistics activity at McMurdo Station, the principal U.S. base. As a consequence contamination of the natural environment has become a problem. A particular example of this contamination is interference to communications receivers and sensitive scientific measuring equipment by radio noise. In November 1970 a survey of radio noise levels near McMurdo was conducted to evaluate the possibility of establishing a low-noise experimental station for the operation of sensitive experiments. The instrument used in the survey, a Stoddart NM-25T, was not sensitive enough to measure the atmospheric noise levels at extremely quiet sites, but was suitable for determining the man-made levels near the base. In central McMurdo the man-made levels, which are mainly attributable to power line noise, are about 45 dB greater than the atmospheric levels expected for the area. Furthermore, they are about 60 dB greater than the man-made levels recorded near another Antarctic base. For the McMurdo area to continue to be used for the operation of sensitive equipment some control must be imposed on the installation and operation of equipment that generates noise.     

Very low temperature thermal conductivity and optical properties of Stycast 1266 epoxy

The thermal conductivity of Stycast 1266 epoxy has been measured between 0.045 and 0.45 K. The thermal conductivity closely follows a T(2) behavior in this temperature range. In addition, some room temperature optical properties of this epoxy are reported.     

Vapor-phase Decontamination of Apples Inoculated with Escherichia coli

Improved methods of decontaminating apples containing human pathogens are required. In this study, application of gaseous antimicrobial agents was investigated. An apparatus, which transfers vapor from hot antimicrobial solutions to a treatment vessel, was evaluated with Golden Delicious apples inoculated with E. coli. Vapor from glacial acetic acid at 60°C provided population reductions exceeding 3.5 log₁₀ CFU/g but induced discoloration. Vapor from heated hydrogen peroxide and chlorine dioxide solutions gave reductions ≤ 2 logs. However, chlorine dioxide gas, applied at 20°C in an airtight container, achieved a 4.5 log reduction, with minimal quality loss. Reductions achieved with this treatment greatly exceed those obtained by other decontamination methods for raw commodities.     

Efficacy of 1% Hydrogen Peroxide Wash in Decontaminating Apples and Cantaloupe Melons

Efficacy of 1% hydrogen peroxide (H₂O₂) in decontaminating apples and cantaloupes containing human pathogens was investigated. Apples inoculated with Escherichia coli (ATCC 25922) were washed with 1% H₂O₂ at 20 or 40 °C for 15 or 30 min. Population reductions approaching 3 logs were obtained with all treatments. Comparable reductions were obtained with apples inoculated with 3 strains of E. coli O157:H7, associated with cider outbreaks, and a 5‐strain cocktail. The 1% H₂O₂ treatment was ineffective against E. coli 766 (ATCC 9637; similar to Salmonella Poona) on inoculated cantaloupes. Treatment of apples with 1% H₂O₂ was carried out successfully in a wet dump tank.