8,127 research outputs found
Electromagnetic Radiation Hardness of Diamond Detectors
The behavior of artificially grown CVD diamond films under intense
electromagnetic radiation has been studied. The properties of irradiated
diamond samples have been investigated using the method of thermally stimulated
current and by studying their charge collection properties. Diamonds have been
found to remain unaffected after doses of 6.8 MGy of 10 keV photons and 10 MGy
of MeV-range photons. This observation makes diamond an attractive detector
material for a calorimeter in the very forward region of the proposed TESLA
detector.Comment: 19 pages, 9 figure
Effect of calf-starter protein solubility on calf performance
Three starters containing differently processed protein supplements were fed
to Holstein heifer calves, using an early weaning program. One starter contained
soybean meal. The other starters contained soybean grits processed through an
extrusion cooker to reduce the protein solubility to an intermediate (PDI> 50%) or
low (PDI < 15 %) level. Calf performance was similar on all three starters
Helminth species richness in wild wood mice, Apodemus sylvaticus, is enhanced by the presence of the intestinal nematode Heligmosomoides polygyrus
We analysed 3 independently collected datasets of fully censused helminth burdens in wood mice, Apodemus sylvaticus,
testing the a priori hypothesis of Behnke et al. (2005) that the presence of the intestinal nematode Heligmosomoides polygyrus
predisposes wood mice to carrying other species of helminths. In Portugal, mice carrying H. polygyrus showed a higher
prevalence of other helminths but the magnitude of the effect was seasonal. In Egham, mice with H. polygyrus showed a
higher prevalence of other helminth species, not confounded by other factors. In Malham Tarn, mice carrying H. polygyrus
were more likely to be infected with other species, but only among older mice. Allowing for other factors, heavy residual
H. polygyrus infections carried more species of other helminths in both the Portugal and Egham data; species richness in
Malham was too low to conduct a similar analysis, but as H. polygyrus worm burdens increased, so the prevalence of other
helminths also increased. Our results support those of Behnke et al. (2005), providing firm evidence that at the level
of species richness a highly predictable element of co-infections in wood mice has now been defined: infection with
H. polygyrus has detectable consequences for the susceptibility of wood mice to other intestinal helminth species
Effects of morinda citrifolia (noni) and diet complexity on growth performance in weanling pigs
Two experiments were conducted to determine the effects of concentration (0, 0.75, 1.5, 3.0, and 6.0%) of Morinda citrifolia (no-ni; Morinda Agricultural Products, Orem, UT) and diet complexity in weanling pigs. In Exp. 1, 210 pigs (initially 13.4 lb) were used in a 35-d growth assay; there were 7 pigs per pen and 6 pens per treatment. Diets were corn-soybean meal-based, and lysine concentrations were 1.8% for d 0 to 7, 1.6% for d 7 to 21, and 1.4% for d 21 to 35 with feed and water con-sumed on an ad libitum basis. Increasing the concentration of noni in the diet from 0 to 3% had no effects on pellet durability index (PDI) for the d 0 to 7 and 7 to 21 diets. Average daily gain (quadratic effect, P < 0.03) and F/G (quadratic effect, P < 0.10) for d 0 to 7 and F/G for d 0 to 21 (quadratic effect, P < 0.04) improved as noni concentration in the diet was increased from 0 to 0.75%. However, no treatment effects were observed overall (d 0 to 35). For Exp. 2, 168 pigs (initially 13.9 lb) were used in a 35-d growth assay; there were 6 pigs per pen and 7 pens per treatment. Treatments were arranged as a 2 × 2 factorial with main effects of diet formulation (simple vs. complex) and noni addition (0 vs. 3%). Simple diets had the same minimum nutrient specifications as complex diets but had no added lactose or spray-dried animal plasma for d 0 to 7 and only 10% added whey for d 7 to 21. Pelleting data indicated improved PDI with no additional energy inputs when noni was added to the simple diets (for d 21 to 35). Pigs fed simple diets had lower ADG (P < 0.06) for d 0 to 7 and lower ADG and ADFI (P < 0.06) for d 0 to 21 than pigs fed complex diets. During d 0 to 35 for ADG and d 0 to 21 for F/G, addition of noni to the simple diets had negative effects (diet complexity × noni interaction, P < 0.02). In conclusion, adding 0.75 to 3% noni to complex diets improved growth performance early in a titration experiment but had negative effects when added to the simple diet formulations used in a second experiment
Evaluation of a portable mixer and feed delivery system
An on-farm mixer uniformity study was conducted to determine if feed could be properly mixed and maintained as it went through a bulk bin and conveying equipment over a distance of 180 ft. in a grower-finisher facility. A portable vertical mixer was tested and found to produced a uniformly mixed feed. Uniform feed was then conveyed from a bulk storage bin to feeders inside the facility. Samples were obtained from three different feeders and were tested for uniformity. Results indicate that feed remains uniform as it is conveyed and deposited in feeders over distances of 20, 80, and 180 ft.; Swine Day, Manhattan, KS, November 21, 199
Copro-antigen capture ELISA for the detection of Teladorsagia (Ostertagia) circumcincta in sheep: improvement of specificity by heat treatment
A copro-antigen capture ELISA for the detection of Teladorsagia circumcincta infection in sheep was developed and evaluated. Experiments with faeces from worm-free sheep, that had been spiked with known concentrations of excretory-secretory (E–S) antigen indicated that a positive signal was generated with 180 ng of E–S/ml. A nested design, based on 8 infected and 8 worm-free sheep, was employed to assess the stages during sample preparation contributing to variation in signal from the assay. This showed that 87% of the variance in the optical density readings (ODs) was directly explained by infection status. Variation between individual sheep within infection groups, and between samples at various stages in the assay, collectively accounted for the remaining variance. Initial evaluation of specificity using faeces from animals carrying a range of monospecific infections indicated cross-reactivity with Haemonchus contortus and Nematodirus spathiger. However, by treating the supernatant from faeces for 20 min at 100°C, the cross-reactive signal was eliminated whilst the specific signal was largely preserved. Heat treatment of faeces from 12 non-infected sheep, 12 sheep with T. circumcincta and 6 with H. contortus resulted in sensitivity being increased from 66.7 to 85.7%, and specificity from 62.5 to 87.5%. OD values showed a significant positive relationship with adult worm burdens, although at low infection intensities there was some overlap between infected and worm-free animals. We discuss the application of CC-ELISAs in facilitating selective chemotherapy of sheep, as a means of avoiding the development of anthelmintic resistance in pastoral regions where sheep are farmed on a large scale
Epidemiology and fitness effects of wood mouse herpesvirus in a natural host population
Rodent gammaherpesviruses have become important models for understanding human herpesvirus diseases. In particular, interactions between murid herpesvirus 4 and Mus musculus (a non-natural host species) have been extensively studied under controlled laboratory conditions. However, several fundamental aspects of murine gammaherpesvirus biology are not well understood, including how these viruses are transmitted from host to host, and their impacts on host fitness under natural conditions. Here, we investigate the epidemiology of a gammaherpesvirus in free-living wood mice (Apodemus sylvaticus) and bank voles (Myodes glareolus) in a 2-year longitudinal study. Wood mouse herpesvirus (WMHV) was the only herpesvirus detected and occurred frequently in wood mice and also less commonly in bank voles. Strikingly, WMHV infection probability was highest in reproductively active, heavy male mice. Infection risk also showed a repeatable seasonal pattern, peaking in spring and declining through the summer. We show that this seasonal decline can be at least partly attributed to reduced recapture of WMHV-infected adults. These results suggest that male reproductive behaviours could provide an important natural route of transmission for these viruses. They also suggest that gammaherpesvirus infection may have significant detrimental effects in wild hosts, questioning the view that these viruses have limited impacts in natural, co-evolved host species
Analytical performance of the selective multianalyser Olympus AU 5200
The analytical performance of a selective, automatic multianalyser- the Olympus A U5200 - was tested and assessed for practicability, following ECCLSguidelines. Twenty-two analytes were tested and compared with the Olympus A U5000 analyser. A Hitachi 747 analyser was also included in this survey in order to obtain correlation data for ISE measurements
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