Outer Box Research Articles

Maternal influence on activity rhythms and reproductive development in Djungarian hamster pups.

Photoperiodism and entrainment of the circadian rhythm of locomotor activity were investigated in juvenile Djungarian hamsters. Animals were housed in simulated burrows. Activity was measured as the animal's emergence from a dark nest chamber into an outer box exposed to the room illumination. This burrow emergence activity exhibited marked circadian rhythmicity. Interactions between mother hamsters and their offspring were examined in the simulated burrow system. Male reproductive responses were determined by measuring testicular weights at the time of weaning. It was shown that photoperiodic information received between Days 1 and 15 of life failed to alter the rate of testicular development, but that after Day 15 testicular growth was photoperiod-dependent. The mother, when entrained to a long photoperiod, did not influence the photoperiodic responses of her pups when they were confined to a dark nest box. In contrast, the mother did influence the circadian entrainment patterns of her pups. Pups exhibited a well-developed circadian activity rhythm at weaning with a phase angle roughly similar to that of the mother's activity rhythm. When the maternal rhythms were discrepant with photoperiod information received by the pups directly from the environment, the pups' activity rhythms were synchronized with the light/dark cycle rather than with the rhythm of their mother. Thus, it appears that although pups may first become entrained by maternal cues, they rapidly adjust to the environmental light cycle after leaving the nest.

A Weighing Lysimeter for Evapotranspiration and Root Measurements1

AbstractCrop water use is intimately tied to soil water and rooting patterns. Therefore, a lysimeter was fabricated which is unique in that root density and water content measurements can be made throughout an undisturbed soil profile coincident with whole‐profile evapotranspiration measurements. With this lysimeter, interrelationships throughout this soil profile between rooting depth and density, soil water content, plant water uptake, and evaporative demand can be evaluated. The lysimeter was constructed with a steel outer and inner box. The inner box contained an undisturbed soil monolith and was set on a scale, which in turn was set on the outer box floor. The 2.0 by 1.5 by 2.54 m monolith was obtained by forcing a steel box over a soil pedestal. Root growth and density and soil water are capable of being monitored throughout the monolith by using 36 clear, extruded acrylic tubes that were inserted horizontally through the monolith at various depths. Most of the soil mass is counterbalanced and the system is capable of resolving water mass changes equivalent to 0.02 mm. Evapotranspiration rates determined from the lysimeter compare favorably with empirical estimates. Costs for the facility and manpower requirements for operations and maintenance are substantial. However, root and soil water measurements, which are possible with this lysimeter, in conjunction with total‐profile water loss measurements, provide a means for quantitatively evaluating interrelationships throughout the profile between these important phenomena.

The general dynamics superconducting magnet for the large coil program--A progress report

The General Dynamics magnet for the Large Coil Program (LCP) has progressed to the fabrication phase. All superconductor and structural details have been completed along with the bobbin, which has been insulated for winding. Outer ring and torque box subassemblies are being welded and readied for coil closeout.

CONTAMINATION OF SEVERAL BREAKFAST CEREALS BY METHYL CHLOROFORM

The analysis of several breakfast cereals has shown that methyl chloroform (MCF, 1,1,1‐Trichloroethane), a solvent found to be present in the adhesive of the outer box, can migrate from the adhesive through the box and the waxed liner into the cereal. The levels of MCF in the adhesive, the outer box, the waxed liner and the cereal were found to range from 0 to 2.3%, 0 to 19.4 ppm, 0 to 4.8 ppm, and 0 to 0.40 ppm, respectively, in 11 breakfast cereals. The MCF residues were determined using a closed system‐vacuum distillation gas chromatographic technique with both electron capture and electrolytic conductivity detection. The results were confirmed by high resolution mass spectrometry.

Consumer Choices Can Reduce Packaging Waste

When all packaging is accounted for, it adds up to about one-third of all the trash that's thrown away in the United States. Industry and business are responsible for most of this waste, but consumer product packaging accounts for about 15 percent of what's discarded. When you purchase a frozen dinner, you are paying for not only the meal but for the outer paperboard box, the plastic or foil tray that holds the meal, and the covering over the food. You pay again for packaging, directly or indirectly, when your garbage is picked up and disposed of in a landfill or incinerator. Some communities are moving toward "pay-as-you-throw" fees for every bag put out at the curb, so it makes sense to reduce household waste. Composting, recycling, and reusing items all help. And by shopping carefully you can reduce excess packaging that you would throw away. This document is ABE328, one of a series of the Agricultural and Biological Engineering Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. First published September 2002. 
 https://edis.ifas.ufl.edu/ae226

Observations on certain physiological processes of the marmot. I.—The heart

In the autumn of 1929 thirteen marmots were brought to Cambridge by one of us (Endres) after the hibernation period had commenced. Of these, we owe four to the kindness of Prof. Adolph Löwy of the Schweizer Forschungsinstitut at Davos. The remainder came from Roffna near the Julier Pass. During the first few days of their captivity in Cambridge they were kept at about 5° C. in the Low Temperature Station, and for this hospitality we would like to thank Sir William Hardy. This temperature proved too low. One of the most remarkable facts about marmots, which has been described by Mangili is that they can be awakened, not only by heat but by cold; at temperatures slightly above 0° C. several of the marmots woke. We shall have to refer to this phenomenon later. The marmots were then placed in an unheated wooden “Army hut,” in a wooden box which was contained in a much larger box. Between the two boxes was sawdust. Also sawdust and hay were put in the small box. The smaller box was covered with a lid, and there was a hole in the side, through which the marmots could leave the inner box for purposes of defæcation or micturition. It is stated in the literature that a marmot wakes up about once in three weeks for this purpose. Our experience was that, when the animals first came, they performed the functions of micturition and defæcation more frequently that at a later stage in the winter. They were losing water all the time, which was not replenished. The temperature of the box containing the marmots was always above that of the outside air. During the winter of 1929-30 there was very little frost, and the lowest temperature noted on the “minimum” registering thermometer in the outer box was 2° C., and that only once.

Studies in the heat-production associated with muscular work. (Preliminary communication: section A.—Methods; section B.—Results.)

The calorimeter with which the included data have been obtained was built upon the plan described by Benedict, omitting, however, such parts as were essential rather to a study of the respiratory gases than to measurements of heat-production. The general principles of its construction are well known, exceedingly ingenious, were developed by Atwater and Benedict, and are briefly as follows: The body of the calorimeter is of sheet copper built upon an external wooden framework, on which again is built externally an outer zinc box enclosing, but nowhere in contact with, the calorimeter box proper. Between the two metal boxes, sets of thermocouples arranged in groups are utilised to discover any differences of temperature likely to lead to a radiation of heat from one box to the other across the intervening air space partially occupied by the wooden framework. In the walls of a still more external wooden shell are placed means by which heat may be added to or subtracted from the zinc box in a graduated fashion so as to annul any such observed differences in temperature. Thus the zinc box is kept in each of its several zones, each zone corresponding to a group of thermocouples, at the same temperature as the copper box, and the thermal insulation of the calorimeter is thus insured. The subject of the experiment enters the calorimeter by a window space left in the walls of this nest of boxes, and is then sealed in by glass and wax. The heat produced in his body, as well as the heat into which all his mechanical work is finally converted, raises the temperature (1) of an insulated radiator system through which a steady stream of water is maintained; (2) of the calorimeter box; (3) causes some evaporation of water from his respiratory passages and skin, and (4) tends to raise his own temperature. Each one of these four stores of heat is observed in suitable ways, and the summed account of their alterations provides a measure of the heat-production of, or total transformation of energy in, the subject.