Energy Compensation with Exercise is not Dependent on Dose

Background: Exercise induced weight loss is often less than expected due to a coordinated set of compensatory mechanisms that serve to maintain energy homeostasis. The extent to which exercise frequency, duration, intensity and exercise energy expenditure (ExEE) influences the compensatory response to an exercise-induced energy deficit (energy compensation) is controversial. Determining how these variables impact energy compensation would help health care providers prescribe exercise with greater probability of creating a sustained negative energy balance and subsequent weight loss. Methods: 44 Overweight/obese men and women (BMI=25-35kg/m²) aged 18 to 40 years were randomized to perform aerobic exercise 2 or 6 days/week or into a sedentary control group for 12 weeks. Changes in body composition and rates of energy expenditure at rest and during physical activity were assessed. Exercise sessions were evaluated for duration, intensity, and ExEE. Energy compensation was determined by comparing changes in bodily energy stores to total ExEE and expressed as both % energy compensated (compensation index, CI) and total energy compensated (kcal). Results: No differences in energy compensation (CI or total energy compensated) were observed between groups exercising two or six days per week. ExEE, time spent exercising per week, or exercise intensity did not influence CI or total energy compensated. Greater fat mass was lost (-1.77 kg) when weekly ExEE exceeded 2,000 kcal compared to under 2,000 kcal (-0.41 kg, p\u3c 0.05), ExEE predicted % fat mass loss (p\u3c 0.05) when controlling for total energy compensated. Conclusion: Greater exercise intensity, frequency, ExEE or exercise duration do not promote greater energy compensation when expressed as CI or total energy compensated. When energy compensated is held constant, greater ExEE promote fat mass loss. ExEE over 2,000 kcal/week is needed to overcome the compensatory response and reduce fat mass

Significance Testing at Sites 41FY170 and 41FY509, Fayette County, Texas

Site 4.1FY509 was originally tested by Texas Department of Transportation (TxDOT) archaeologists in April 1991. Based on the findings of the initial testing, the site was determined ineligible for inclusion in the National Register of Historic Places. Because cultural deposits were discovered during construction, additional archaeological investigations were conducted by TxDOT archaeologists on the eastern portions of 41FY509, Plum, Fayette County, Texas. The recent investigations were conducted in the right-of-way of Highway 71 between centerline stations 395+00 and 390+00 of the Plum Bypass. These investigations were conducted between June 3 and July 5, 1993, and consisted of mechanical trenching, removal of the topsoil over approximately 50 percent of the area with a road grader, and hand excavation. The results of this investigation revealed two distinct cultural deposits within shallow strata containing a total of 12 burned rock features. The first cultural deposit was confined to a single burned rock feature which produced extensive carbon deposits. This feature was provenienced directly above a substrate burned rock feature of a lower cultural deposit, and likely dates to the Late Prehistoric period or more recent. The lower cultural deposit consisted of 11 burned rock features averaging 1.5 to two m in diameter evenly distributed across the exposed area. The features of this occupation likely date to the Early or Middle Archaic periods. The base of the lower cultural deposit lies directly on or two to four centimeters above substrate clays. Both cultural deposits were confined to shallow soils ranging in depth from 20-50 cm below the surface. Since the artifact density in this portion of 41FY509 is comparatively low and no clearly diagnostic artifacts were found in direct association with any of the features, the cultural affiliations and temporal placement of the two occupational strata remain enigmatic. Due to the shallow nature of the deposits and the relative lack of associated diagnostic artifacts, the eastern portion of 41FY509 is not considered eligible for inclusion in the National Register of Historic Places

The histology of voluntary muscle in cattle and changes which occur during fattening

Abstract derived from the Introduction section of the thesis: The present investigation does not enter into a general consideration of the histology or voluntary striated muscle but is confined to a few phases of the subject. The occurrence of fat in the muscle fiber will be considered in some detail. Some observations bearing on the changes in striated muscle incident to fattening, growth, and inanition will be presented

Results of Significance Testing at 41DW269 Dewitt County, Texas

Site 41DW269 was tested by Texas Department of Transportation (TxDOT) archeologists in July of 1997. The investigations were conducted in the right-of-way of a proposed bridge replacement project on DeWitt County Road 122 at its crossing of Clear Creek. The investigations at Site 41DW269 consisted of mechanical trenching for archeological prospection and stratigraphic evaluation of the site, and the manual excavation of two 1 x 1 m test units and two shovel tests. Site 41DW269 is a multi-component terrace site with cultural deposits ranging in age from the Early Archaic through the Late Archaic. Two discrete alluvial fills, both containing cultural material, underlie the terrace. Unit 1 forms the core of the terrace and consists of a dark brown, sandy to silty loam to clay loam containing abundant secondary calcium carbonate. Unit 2 consists of a very dark grayish brown to black loam that represents a veneer of more recent overbank deposits that is approximately 1.0 to 1.2 m thick. In addition, two younger alluvial fills (Units 3 and 4) are present across the stream and at the base of the cutbank forming the northern site boundary. Testing of the site revealed two clearly distinct prehistoric cultural strata within deep alluvial deposits, and a single pit-like feature. The first cultural deposit is associated with Unit 1, and consists of a sparse assemblage of mineralized bone and lithic material extending from approximately 120-180 cm below the present ground surface. On the basis of a single radiocarbon age and a diagnostic Guadalupe tool, this component is believed to date to the Early Archaic. The second cultural deposit is associated with the upper veneer, and extends from approximately 10 cm to 110 cm below the surface. Although this deposit could not be subdivided based on the limited excavation data, it contains a cultural debris associated with Late Archaic and possibly Middle Archaic occupations Due to the deep and stratified nature of the deposits and the diversity of artifactual assemblages at the site, 41DW269 is considered eligible for inclusion in the National Register of Historic Places and for designation as a State Historic Landmark

Individual variability in Diel Vertical migration of a marine copepod : why some individuals remain at depth when others migrate

The diel vertical migration (DVM) of the copepod Metridia pacifica was examined in Dabob Bay (47°45.05′N, 122°49.71′W), a fjord in Washington state. Although the population showed deep daytime residence (75-175 m), a proportion of the population was found in the surface waters at night. For individuals that migrated to the surface, the mean size of the oil sac was much smaller than those that remained at depth (mean lengths of oil sac 0.25 mm for individuals collected between 0 and 25 m at night, compared with 0.43 mm for individuals from between 125 and 175 m). Similarly, the C : N ratio was lower for animals collected from near the surface, indicative of their lower lipid reserves. These results suggest that individual variability in DVM was influenced by body condition, with those animals with larger lipid stores not needing to risk coming to the surface to feed at night

Real-time Ultrasound Trait Age Adjustment Factors for Replacement Angus Heifers

Real-time ultrasound (RTU) images from replacement Angus heifers were analyzed to determine adjustment factors and genetic parameter estimates. The traits analyzed included ribeye area, 12-13th rib fat thickness, rump fat thickness, and % intramuscular fat. Adjustments were calculated for heifers averaging 805 lbs at time of scanning. The adjustments include age adjustment and weight per day of age adjustment factors

Adjustment Factors for Ultrasound Measures in Yearling Angus Bulls and Developing Heifers

Ultrasound measures for 12-13th rib fat thickness, rump fat thickness, ribeye area and % intramuscular fat have been collected on more than 27,000 yearling Angus bulls and more than 7,000 developing heifers as part of a two-year research program with the American Angus Association. The effects of the age of the cow producing the calf and the age of the calf at scanning time are significant and must be accounted for through adjustments to the actual ultrasound measures before breeders can use the information to compare animals within contemporary groups

Carcass EPDs for Yearling Angus Bulls Using Real-time Ultrasound Measures

Real-time ultrasound (RTU) images from yearling Angus bulls were analyzed to determine adjustment factors and genetic parameter estimates. The traits analyzed included ribeye area, 12-13th rib fat thickness, rump fat thickness, and % intramuscular fat. The heritability estimates are higher than those calculated from the American Angus Association’s carcass database. Expected progeny differences (EPD) for these traits were computed for the sires that produced the yearling bulls. The rank correlations for sires with both carcass EPD and RTU EPD from this study were developed. As accuracy for RTU EPD increases, the rank correlation with carcass EPD increases positively