Body Temperature in Free-Roaming Beef Cattle

Body temperature (BT) measurements are traditionally used in diagnosing sick animals, but may also be used as an indicator of stress or activity. Based on results of metabolism studies, Mader et al. (1999) reported that BT can vary as much as 0.9oC and can depend on metabolisable energy (ME) of the diet consumed. Acceptable measures of BT can be obtained from the rectum, vagina, or ear canal. Technologies are also being developed for continuously monitoring BT via radio-telemetry. The objectives of this study were to determine the effect of high concentrate (low fibre) versus high fibre diets on BT, assess the capabilities of obtaining BT in free-roaming cattle, and compare temperatures taken in the rumen with vaginal and tympanic temperatures

A direct optical method for the study of grain boundary melting

The structure and evolution of grain boundaries underlies the nature of polycrystalline materials. Here we describe an experimental apparatus and light reflection technique for measuring disorder at grain boundaries in optically clear material, in thermodynamic equilibrium. The approach is demonstrated on ice bicrystals. Crystallographic orientation is measured for each ice sample. The type and concentration of impurity in the liquid can be controlled and the temperature can be continuously recorded and controlled over a range near the melting point. The general methodology is appropriate for a wide variety of materials.Comment: 8 pages, 8 figures, updated with minor changes made to published versio

Abrupt grain boundary melting in ice

The effect of impurities on the grain boundary melting of ice is investigated through an extension of Derjaguin-Landau-Verwey-Overbeek theory, in which we include retarded potential effects in a calculation of the full frequency dependent van der Waals and Coulombic interactions within a grain boundary. At high dopant concentrations the classical solutal effect dominates the melting behavior. However, depending on the amount of impurity and the surface charge density, as temperature decreases, the attractive tail of the dispersion force interaction begins to compete effectively with the repulsive screened Coulomb interaction. This leads to a film-thickness/temperature curve that changes depending on the relative strengths of these interactions and exhibits a decrease in the film thickness with increasing impurity level. More striking is the fact that at very large film thicknesses, the repulsive Coulomb interaction can be effectively screened leading to an abrupt reduction to zero film thickness.Comment: 8 pages, 1 figur

CASE STUDY: Tympanic Temperature and Behavior Associated with Moving Feedlot Cattle

Body temperature is often used as an indicator of animal health status. In a series of handling experiments, tympanic temperatures (TT) were obtained in unrestrained feedlot cattle. In a January experiment (BW = 531 ± 54 kg), TT were increased (

Environmental Effects on Pregnancy Rate in Beef Cattle

Ten years of calving records were examined from Bos taurus crossbred cows (mean of 182 cows/ yr) to quantify the effects of environmental conditions during the breeding season on pregnancy rate. Estimated breeding dates were determined by subtracting 283 d from the calving date. Relationships were determined between the proportion of cows bred during the periods from the beginning of the breeding season until d 21, 42, and 60 of the breeding season and the corresponding environmental variables. Weather data were compiled from a weather station located approximately 20 km from the research site. Average daily temperature and relative humidity were used to calculate daily temperature-humidity index (THI). Daily averages for each environmental variable were averaged for each period. Minimum temperature (MNTP) and THI for the first 21 and 42 d of the breeding season were negatively associated (P \u3c 0.001) with pregnancy rate. For the 0- to 21-d, 0- to 42-d, and 0- to 60-d breeding periods, respective r2 for average temperatures were 0.32, 0.37, and 0.11, whereas r2 for MNTP were 0.45, 0.40, and 0.10 and r2 for THI were 0.38, 0.41, and 0.11, respectively, for the same breeding periods. The negative associations of temperature and THI with pregnancy rate are most pronounced during the first 21 d of the breeding season, with a −3.79 and −2.06% change in pregnancy rate for each unit of change in MNTP and THI, respectively. A combination of environmental variables increased the R2 to 0.67. In this analysis, windspeed was found to be positively associated with pregnancy rate in all equations and increased the R2 in all breeding periods. Optimum MNTP for the 0- to 21-d, 0- to 42-d, and 0- to 60- d breeding periods was 12.6, 13.5, and 14.9°C, respectively. For the 0- to 60-d breeding period, optimum THI was 68.0, whereas the THI threshold, the calculated level at which cattle will adapt, was found to be 72.9. Reductions in pregnancy rate are likely when the average MNTP and THI equal or exceed 16.7°C and 72.9, respectively, and for Bos Taurus beef cows that are pasture bred during a 60-d spring-summer period

How universal is the fractional-quantum-Hall edge Luttinger liquid?

This article reports on our microscopic investigations of the edge of the fractional quantum Hall state at filling factor $\nu=1/3$. We show that the interaction dependence of the wave function is well described in an approximation that includes mixing with higher composite-fermion Landau levels in the lowest order. We then proceed to calculate the equal time edge Green function, which provides evidence that the Luttinger exponent characterizing the decay of the Green function at long distances is interaction dependent. The relevance of this result to tunneling experiments is discussed.Comment: 5 page

COMPARING FUNCTIONAL DATA ANALYSIS AND HYSTERESIS LOOPS WHEN TESTING TREATMENTS FOR REDUCING HEAT STRESS IN DAIRY COWS

Various techniques are commonly used to reduce heat stress, including sprayers and misters, shading, and changes in feed. Oftentimes studies are performed where researchers do not control the times when animals use shading or other means available to reduce heat stress, making it hard to test differences between treatments. Two methods are used on data from a study where Holstein cows were given free access to weight activated “cow showers.” Functional data analysis can be used to model body temperature as a function of time and environmental variables such as the Heat Load Index. Differences between treatment groups can be tested using a Functional Bayesian MCMC model. Alternatively hysteresis loops, such as the ellipse, formed by a plot of air temperature or the Heat Load Index against body temperature over the course of a day can be estimated and their parameters used to test differences between cows with access to showers and cows without. Results from an R package hysteresis, which can estimate these loops and their parameters are illustrated. Functional data analysis allows for looser assumptions regarding the body temperature curve and the ability to look for differences between groups at specific time points, while hysteresis loops give the ability to look at heat stress over the course of a day holistically in terms of parameters such as amplitude, lag, internal heat load and central values

Education, employment and marriage in long-term survivors of teenage and young adult cancer compared with healthy controls

QUESTIONS UNDER STUDY: Teenage and young adult (TYA) cancer patients are faced with the diagnosis during a challenging period of psychosocial development that may affect social outcomes in the long term. Therefore, we aimed to: (1) determine differences in social outcomes between long-term TYA cancer survivors and healthy controls and (2) identify factors associated with adverse social out-comes. METHODS: We sent a questionnaire to TYA cancer survivors (aged 16-25 years at diagnosis, ≥5 years after diagnosis) registered in the Cancer Registry Zurich and Zug. Information on controls was obtained from the Swiss Health Survey 2012. We assessed educational achievement, employment status, marital status and life partnership (survivors only), and compared these outcomes between survivors and controls. We used logistic regression to identify sociodemo-graphic and cancer-related factors associated with social outcomes. RESULTS: We included 160 TYA cancer survivors and 999 controls. Educational achievement of survivors differed significantly from controls (p = 0.012): more survivors than controls reported upper secondary education (33 vs 27%) and fewer survivors reported uni-versity education (12 vs 21%). No significant differences were found for employment (p = 0.515) and marital status (p = 0.357). The major-ity of survivors (91%) and controls (90%) were employed, and 37% of survivors were married, compared with 41% of controls. There were no cancer-related factors associated with having only basic educa-tion. Unemployment was associated with younger age at diagnosis (odds ratio [OR] 5.3, 95% confidence interval [CI] 1.3-30.8) and self-reported late effects (OR 4.7, 95% CI 1.3-19.5). Survivors of younger age at diagnosis were more likely not to be married (OR 2.7, 95% CI 1.3-5.7) and not to have a life partner (OR 2.3, 95% CI 1.0-5.2). CONCLUSIONS: Our findings indicate that TYA cancer survivors com-pleted applied higher education rather than a university education. Future studies including larger samples of TYA cancer survivors are needed to validate our findings and to explore the reasons for and satisfaction with the observed educational pathway