The Rocketdyne Multifunction Tester. Part 1: Test Method

The Rocketdyne Multifunction Tester is a general purpose test apparatus which utilizes axial and radial magnetic bearings as shaft excitation devices. The tester is modular in design so that different seal and bearing packages can be tested on the same test stand. The tester will be used for rotordynamic coefficient extraction, as well as life and fluid/material compatibility evaluations. Use of a magnetic bearing as a shaft excitation device opens up many possibilities for shaft excitation and rotordynamic coefficient extraction. In addition to describing the basic apparatus, some of the excitation and extraction methods are described. Some of the excitation methods to be discussed include random, aperiodic, harmonic, impulse and chirp

Observations of Red-Tailed Hawks Capturing Wild Ducks in North Dakota

Ducks (Anserifonnes; Anatinae) are preyed on by red-tailed hawks (Buteo jamaicensis) in the northern Great Plains of North America, yet I found no published, direct observations of captures of wild ducks by red-tailed hawks in the region. I made the following observations in south central Burke County, northwestern North Dakota

AQ Intervention for Assessing and Counseling Students of Color at Predominantly White Institutions

Learn about the power of the Affective Domain for Students of Color. Participants have the chance to see that the Affective domain is just as important as the Cognitive domain. They will see how the Affective domain is critically vital for the assessment and counseling of Students of Color, particularly at predominantly white institutions

AQ Intervention for Assessing and Counseling Students of Color at Predominantly White Institutions

Learn about the power of the Affective Domain for Students of Color. Participants have the chance to see that the Affective domain is just as important as the Cognitive domain. They will see how the Affective domain is critically vital for the assessment and counseling of Students of Color, particularly at predominantly white institutions

Amphibians and Reptiles in a Mixed-Grass Prairie in Northwestern North Dakota

There have been almost no surveys of herpetofauna at 109 km2 Lostwood National Wildlife Refuge (LNWR) or surrounding counties in northwestern North Dakota, an area possibly undergoing significant environmental change from fossil fuel extraction and use. We used 30 m drift fences to survey amphibian and reptile species in prairie-wetland transition zones at LNWR during mid-May to early-July in 1985 to 1987, and again in 1999 and 2000. We captured only four amphibian and two reptilian species and noted one other reptilian species incidental to our survey. Several species expected to occur in the area were not detected

Fire History, Passerine Abundance, and Habitat on a North Dakota Drift Plain Prairie

Prescribed fire is among key tools for restoring and managing prairies in the northern Great Plains, yet there are no published reports of its impacts on grassland passerine birds on native prairie in the Drift Plain, a major physiographic subregion. We examined relationships between prescribed fire history and abundance and habitat of breeding passerines in Drift Plain prairie at Des Lacs National Wildlife National Refuge in northwestern North Dakota. In 2003, we used point counts (n = 79 75 m radius plots) to survey bird abundance on 16 management units that had been prescribe-burned one to three times each since 1992. General habitat composition and structure also were measured at each point count plot. We detected 14 passerine species, six of which were common (occurred on greater than 10% of plots). Three endemic, historically common passerine species were rare or absent regardless of fire history. Abundances of common bird species were not influenced strongly by fire history, which contrasts with data from research on the adjacent Missouri Coteau physiographic subregion. Vegetation structure (litter depth and plant height-density) and occurrence of an exotic grass species, smooth brome (Bromus inermis), decreased with fire history. However, we detected no relationships between bird species abundances and these particular vegetation variables, perhaps because smooth brome continued to be a pervasive structural influence on all management units. Our findings indicate a need for better understanding of bird-fire relationships on remnant prairies in the vast Drift Plain

High Abundance of Nesting Long-Eared Owls in North Dakota

The long-eared owl (Asio otus) is a secretive, poorly understood species in the Great Plains of the United States and Canada. In North Dakota the long-eared owl has been considered a species of special concern (Petersen 1991), due mainly to lack of information on its occurrence and nesting status. We discovered 39 long-eared owl nests while searching for Cooper\u27s hawk (Accipiter cooperii) nests in northwestern and north central North Dakota during April and May 2000. Long-eared owl nests mainly were observed at J. Clark Salyer and Des Lacs National Wildlife Refuges (NWRs) in the Souris River basin (for study area descriptions see Nenneman et al. 2002) and at Lostwood NWR on the Missouri Coteau landform (Murphy 1993). These 39 nests exceed the total of all state breeding records for the long-eared owl through the early 1970\u27s (Stewart 1975: 159). During 1994 to 1999 we annually found 2 to 12 long-eared owl nests while searching for Cooper\u27s hawk nests in approximately the same area of North Dakota

Animal performance and economic implications of alternative production systems for dairy bulls slaughtered at 15 months of age

peer-reviewedThe objectives of this experiment were to investigate (i) the influence of varying levels of concentrate supplementation during the grazing season, (ii) alternative finishing strategies for dairy bulls slaughtered at 15 mo of age and (iii) economic implications of these management strategies. Bulls were assigned to a 2 (level of concentrate supplementation during the grazing season: 1 kg [LA] and 2 kg [HA] dry matter [DM]/head daily) × 2 (finishing strategies: concentrates ad libitum group [AL] or grass silage ad libitum plus 5 kg DM of concentrates/head daily group [SC]) factorial arrangement of treatments. Average daily gain (ADG) during the grazing season was greater (P < 0.01) for HA than for LA. Consequently, HA bulls were 16 kg heavier at housing: 214 and 230 kg, respectively (P < 0.05). During the finishing period, ADG tended (P = 0.09) to be greater for LA than for HA. Carcass weight tended (P = 0.08) to be greater for HA than for LA. Fat score was greater for HA. Live weight at slaughter (P < 0.001) and carcass weight (P < 0.001) were 41 and 23 kg greater for AL than for SC, respectively. Conformation (P < 0.05) and fat score (P < 0.05) were greater for AL than for SC. The Grange Dairy Beef Systems Model simulated whole-farm system effects of the production systems. Net margin/head was greater for LA than for HA and greater for SC than for AL. Sensitivity analysis of finishing concentrate price, calf purchase price and beef price showed no re-ranking of the systems on a net margin basis. Although greater animal performance was observed from the higher plane of nutrition, overall profitability was lower.This project (11/SF/322, “BullBeef”) was funded by the Irish Department of Agriculture, Food and the Marine’s competitive research programmes

Mortality of Cranes (Gruidae) Associated with Powerlines over a Major Roost on the Platte River, Nebraska

Two 69-kilovolt powerlines spanning the Platte River in south central Nebraska are suspected to cause substantial mortality to sandhill cranes (Grus canadensis) and pose a threat to endangered whooping cranes (G. americana) that roost overnight on the river during spring and fall migrations. Most studies of crane collisions with powerlines in the region have focused on counts of carcasses away from night roosts on the river and none have accounted for potential biases in detecting carcasses. We found 61 carcasses of sandhill cranes below over-river segments of the two powerlines during 4 March to 7 April 2006 and 90 such carcasses between 5 March and 13 April 2007. In 2007 we estimated the number of carcasses undetected in our surveys due to removal by scavengers, loss to downstream flow, and observer oversight. We estimated between 165 and 219 sandhill cranes were killed by the two powerlines during spring 2007. These cnlculations exclude mortalities from individuals injured by powerline collisions and dying elsewhere, as well as those killed before or after our 5 March to 13 April survey period. We detected no evidence of mortality for whooping cranes during our surveys. Our results corroborate anecdotal evidence of signficant sandhill crane mortality each spring due to collisions with above-ground powerlines at this major night roost. Collisions by sandhill cranes will continue and collisions by Whooping cranes seem likely unless an effective means of averting birds from powerlines is implemented at this site

Spatial variation in the fine-structure constant -- new results from VLT/UVES

(abridged) We present a new analysis of a large sample of quasar absorption-line spectra obtained using UVES (the Ultraviolet and Visual Echelle Spectrograph) on the VLT (Very Large Telescope) in Chile. In the VLT sample (154 absorbers), we find evidence that alpha increases with increasing cosmological distance from Earth. However, as previously shown, the Keck sample (141 absorbers) provided evidence for a smaller alpha in the distant absorption clouds. Upon combining the samples an apparent variation of alpha across the sky emerges which is well represented by an angular dipole model pointing in the direction RA=(17.3 +/- 1.0) hr, dec. = (-61 +/- 10) deg, with amplitude (0.97 +0.22/-0.20) x 10^(-5). The dipole model is required at the 4.1 sigma statistical significance level over a simple monopole model where alpha is the same across the sky (but possibly different to the current laboratory value). The data sets reveal a number of remarkable consistencies: various data cuts are consistent and there is consistency in the overlap region of the Keck and VLT samples. Assuming a dipole-only (i.e. no-monopole) model whose amplitude grows proportionally with `lookback-time distance' (r=ct, where t is the lookback time), the amplitude is (1.1 +/- 0.2) x 10^(-6) GLyr^(-1) and the model is significant at the 4.2 sigma confidence level over the null model [Delta alpha]/alpha = 0). We apply robustness checks and demonstrate that the dipole effect does not originate from a small subset of the absorbers or spectra. We present an analysis of systematic effects, and are unable to identify any single systematic effect which can emulate the observed variation in alpha.Comment: 47 pages, 35 figures. Accepted for publication by Monthly Notices of the Royal Astronomical Society. Please see http://astronomy.swin.edu.au/~mmurphy/pub.html for an ASCII version of table A1 and the full set of Voigt profile fits for appendix