Reproducibility of a locomotor test for trotter horses

Locomotion analysis is increasingly used to assess the gait of horses in the selection and training of equine athletes. We have developed a specific locomotor test for fast trotting harnessed horses that uses an accelerometric device. We describe here the reproducibility of the locomotor test and the validation of its use to analyse trotters on the racetrack. We measured the performance of eight horses under the same conditions three times in a single week. We then tested the influence of five tracks on the variables measured using eight different trotters every two days. The horses trotted at three or four velocities (8.3, 10, 11.7 m/s and at maximal velocity) in a straight line for 20 s. The short-term reproducibility of the test was very good for 23/25 variables, with no significant difference in the 23 variables for the three measurements. The two less reproducible variables reflected human error. The different tracks did not alter the stride variables measured. We conclude that the test is an easy, accurate method for analysing gait, as it provides reproducible stride variables for trotting harness horse under field conditions.     

Body condition and frequency of ovarian cysts in Brown Swiss cows during the first 40 days of lactation

For this investigation 50 Brown Swiss cows from 21 different farms were used. Twenty-five peripartal overconditioned cows (back fat thickness > 38 mm) were compared with 25 peripartal not overconditioned animals (back fat thickness < 38 mm). On days 20, 30 and 40 post partum the ovaries were examined sonographically and 10, 15, 20, 30 and 40 days after calving plasma concentrations of progesterone and 17-beta estradiol were determined. In peripartal overconditioned animals 12 ovarian cysts were found while only one cyst was present in not overconditioned cows (P < 0.05). At first examination all ovarian cysts were classified by ultrasound as follicle theca cysts (progesterone < 0.5 ng/ml plasma). Follow examinations resulted in 3 cysts which persisted as theca cysts while 8 cysts became luteinized and 2 cysts completely regressed. There was no indication of increased plasma progesterone and/or estradiol concentrations in overconditioned cows with higher fat deposit before of ovarian cysts had occurred.     

Radioactive wastes: a comparison of u.s. Military and civilian inventories

Contrary to widespread belief, the accumulated inventory of fission products generated by the still small U.S. civilian nuclear power industry may already be comparable to that generated in the past by U.S. military nuclear programs. Although the volumes of the military wastes are very large, they are on the average almost 100 times more dilute than projected commercial high-level wastes.     

Soliton self-frequency shift cancellation in photonic crystal fibers

We report the cancellation of the soliton self-frequency shift in a silica-core photonic crystal fiber with a negative dispersion slope. Numerical and experimental results show that stabilization of the soliton wavelength is accompanied by exponential amplification of the red-shifted Cherenkov radiation emitted by the soliton. The spectral recoil from the radiation acts on the soliton to compensate for the Raman frequency shift. This phenomenon may find applications in the development of a family of optical parametric amplifiers.     

Breed differences and intra-breed genetic variability of dermatoglyphic pattern of cattle

SUMMARY: Muzzle dermatoglyphics - n. ridges, granula and vibrissae - were analysed in various breeds. Differences among these in most traits were significant. Herd effects accounted for about 1/10 of the variance and heritability, estimated by combining sib, halfsib and dam-daughter correlations corrected for herd differences was above 50% for ridges and vibrissae and about 30% for granula. Genetic correlations between ridge counts and n. vibrissae in different nose fields, respectively, were high as they were between the former and n. granula but they were negative or very low between vibrissae and the other two traits. Asymmetry among the counts in the two muzzle sides was significant for nearly all traits, Heritabilities were low, around 10 to 20%, and the crossbreds had less asymmetry than their parental breeds. The correlations among asymmetry measures were low. ZUSAMMENFASSUNG: Rassenunterschiede und genetische Variabilit?t von Flotzmaulmustern Flotzmaulmerkmale - Zahl von Leisten, Warzen und Haaren - wurden in verschiedenen Rassen untersucht. Unterschiede zwischen diesen waren für alle Merkmale signifikant. Herdeneinflüsse verursachten etwa 1/10 der Varianz und Heritabilit?tswerte, gesch?tzt aus Korrelationen zwischen Zwillingen, Halbgeschwistern und T?chter-Müttern, korrigien für Herdeneinflüsse, variierten zwischen 36 und mehr als 50%. Genetische Korrelationen zwischen Leistenzahl und Zahl von Haaren in verschiedenen Flotzmaulfeldern waren hoch, ebenso wie die zwischen ersteren und Zahl von Warzen, aber sie waren negativ oder sehr gering zwischen Haaren und den andern beiden Merkmalen. Asymmetrie zwischen Zahlen in beiden Flotzmaulh?lften war signifikant für fast alle Merkmale. Heritabilit?tswerte waren niedrig, etwa 10-20% und Kreuzungstiere zeigten weniger Asymmetrie als ihre Herkunftsrassen. Die Korrelationen zwischen Asymmetriema?en waren niedrig.     

Fast variability of tera-electron volt gamma rays from the radio galaxy M87

The detection of fast variations of the tera-electron volt (TeV) (10(12) eV) gamma-ray flux, on time scales of days, from the nearby radio galaxy M87 is reported. These variations are about 10 times as fast as those observed in any other wave band and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the gamma-ray production. The observations confirm that TeV gamma rays are emitted by extragalactic sources other than blazars, where jets are not relativistically beamed toward the observer.     

Chloride methylation by plant pectin: an efficient environmentally significant process

Atmospheric chloromethane (CH3Cl) plays an important role in stratospheric ozone destruction, but many uncertainties exist regarding the strengths of its sources and sinks and particularly regarding the processes generating this naturally occurring gas. Evidence is presented here that CH3Cl is produced in many terrestrial environments by a common mechanism. Abiotic conversion of chloride to CH3Cl occurs readily in plant material, with the widespread plant component pectin acting as a methyl donor. Significant CH3Cl emissions from senescent and dead leaves were observed at ambient temperatures; those emissions rose dramatically when temperatures increased. This ubiquitous process acting in terrestrial ecosystems and during biomass burning could contribute the bulk of atmospheric CH3Cl.