Extent of the Muscatine Series in Muscatine County, Iowa

The morphology of the profiles of 35 randomly selected sites in Muscatine County, Iowa, was studied. None of these sites qualified as type locations for the Muscatine series, based on current concepts and definitions of this series. Originally established in Muscatine County in 1916, 38.2 per cent of the soils of the county were classified in this series. Now, Muscatine County seems to be no longer a suitable type location for the Muscatine series

Feeding Concentrate Formulated With Native Irish Feed Ingredients and a Low Crude Protein Content to Grazing Dairy Cows Has No Effect on Milk Production or Milk Composition

Improving nitrogen use efficiency (NUE) and feeding native feed ingredients offers potential to improve the environmental sustainability of dairy production. However, improving NUE is a key challenge in grass-based systems due to high crude protein (CP) levels in grass and low nitrogen retention by dairy cows. In addition, concentrate feed typically contains imported feed ingredients which contribute to increased carbon footprint. Therefore, the objective of this study was to investigate the effect of concentrate CP level and ingredient source on milk production and composition. Forty-two mixed-parity Holstein-Friesian cows were blocked on parity and balanced on days in milk (DIM), milk production, BCS and Economic Breeding Index (EBI; n=14). Cows grazed full time and were offered a basal diet of perennial ryegrass pasture (average 17 kg DM/cow/day) and fed one of three concentrate supplements at varying levels according to DIM during the main grazing season (153 days). The concentrate treatments (T) were: T1) 14% CP concentrate formulated with non-native ingredients, T2) 12% CP concentrate formulated with non-native ingredients or T3) 12% CP concentrate formulated with native ingredients. Reducing the CP level or formulating with native feed ingredients did not alter milk or milk solids yield (T1: 25.7 kg/day, 2.11 kg/day; T2: 25.3 kg/day, 2.06 kg/day; T3: 24.9 kg/day, 2.01 kg/day respectively). Similarly, no effect of treatment was observed for milk fat or protein percentage (T1: 4.40 %, 3.66 %; T2: 4.44 %, 3.64 %; T3: 4.37 %, 3.66 %, respectively). The results of this study highlight that the sustainability of grass-based dairy may be improved by using a low concentrate CP content (12%) in addition to offering concentrate feed based on native feed ingredients which can result in similar performance to that of dairy cows offered a 14% CP concentrate or a concentrate based on imported ingredients respectively

Detection of Neutralino Annihilation Photons from External Galaxies

We consider neutralino annihilation in dense extragalactic systems known to be dominated by dark matter, in particular M87 and several local dwarf spheroidal galaxies. These annihilations can produce energetic gamma rays which may be visible to atmospheric Cerenkov telescopes. We explore the supersymmetric parameter space, and compute the expected flux of gamma--rays coming from these objects. It is shown that some parts of the parameter space lead to a signal observable with the next generation of Cerenkov telescopes, provided the supersymmetric dark matter has a clumpy structure, as may be expected in a hierarchical scenario for structure formation.Comment: revtex: 13 pages, 9 figure

Mining the Plant-Herbivore Interface with a Leafmining Drosophila of Arabidopsis

Experimental infections of Arabidopsis thaliana (Arabidopsis) with genomically characterized plant pathogens such as Pseudomonas syringae have facilitated the dissection of canonical eukaryotic defence pathways and parasite virulence factors. Plants are also attacked by herbivorous insects, and the development of an ecologically relevant genetic model herbivore that feeds on Arabidopsis will enable the parallel dissection of host defence and reciprocal resistance pathways such as those involved in xenobiotic metabolism. An ideal candidate is Scaptomyza flava, a drosophilid fly whose leafmining larvae are true herbivores that can be found in nature feeding on Arabidopsis and other crucifers. Here, we describe the life cycle of S. flava on Arabidopsis and use multiple approaches to characterize the response of Arabidopsis to S. flava attack. Oviposition choice tests and growth performance assays on different Arabidopsis ecotypes, defence-related mutants, and hormone and chitin-treated plants revealed significant differences in host preference and variation in larval performance across Arabidopsis accessions. The jasmonate and glucosinolate pathways in Arabidopsis are important in mediating quantitative resistance against S. flava, and priming with jasmonate or chitin resulted in increased resistance. Expression of xenobiotic detoxification genes was reduced in S. flava larvae reared on Arabidopsis jasmonate signalling mutants and increased in plants pretreated with chitin. These results and future research directions are discussed in the context of developing a genetic model system to analyse insect–plant interactions.Organismic and Evolutionary Biolog

Tracking and imaging gamma ray experiment (TIGRE) for 1 to 100 MEV gamma ray astronomy

A large international collaboration from the high energy astrophysics community has proposed the Tracking and Imaging Gamma Ray Experiment (TIGRE) for future space observations. TIGRE will image and perform energy spectroscopy measurements on celestial sources of gamma rays in the energy range from 1 to 100 MeV. This has been a difficult energy range experimentally for gamma ray astronomy but is vital for the future considering the recent exciting measurements below 1 and above 100 MeV. TIGRE is both a double scatter Compton and gamma ray pair telescope with direct imaging of individual gamma ray events. Multi‐layers of Si strip detectors are used as Compton and pair converters CsI(Tl) scintillation detectors are used as a position sensitive calorimeter. Alternatively, thick GE strip detectors may be used for the calorimeter. The Si detectors are able to track electrons and positrons through successive Si layers and measure their directions and energy losses. Compton and pair events are completely reconstructed allowing each event to be imaged on the sky. TIGRE will provide an order‐of‐magnitude improvement in discrete source sensitivity in the 1 to 100 MeV energy range and determine spectra with excellent energy and excellent angular resolutions. It’s wide field‐of‐view of π sr permits observations of the entire sky for extended periods of time over the life of the mission

The HIPASS Catalogue - II. Completeness, Reliability, and Parameter Accuracy

The HI Parkes All Sky Survey (HIPASS) is a blind extragalactic HI 21-cm emission line survey covering the whole southern sky from declination -90 to +25. The HIPASS catalogue (HICAT), containing 4315 HI-selected galaxies from the region south of declination +2, is presented in Meyer et al. (2004a, Paper I). This paper describes in detail the completeness and reliability of HICAT, which are calculated from the recovery rate of synthetic sources and follow-up observations, respectively. HICAT is found to be 99 per cent complete at a peak flux of 84 mJy and an integrated flux of 9.4 Jy km/s. The overall reliability is 95 per cent, but rises to 99 per cent for sources with peak fluxes >58 mJy or integrated flux > 8.2 Jy km/s. Expressions are derived for the uncertainties on the most important HICAT parameters: peak flux, integrated flux, velocity width, and recessional velocity. The errors on HICAT parameters are dominated by the noise in the HIPASS data, rather than by the parametrization procedure.Comment: Accepted for publication in MNRAS. 12 pages, 11 figures. Paper with higher resolution figures can be downloaded from http://hipass.aus-vo.or

The HIPASS Catalogue: III - Optical Counterparts & Isolated Dark Galaxies

We present the largest catalogue to date of optical counterparts for HI radio-selected galaxies, Hopcat. Of the 4315 HI radio-detected sources from the HI Parkes All Sky Survey (Hipass) catalogue, we find optical counterparts for 3618 (84%) galaxies. Of these, 1798 (42%) have confirmed optical velocities and 848 (20%) are single matches without confirmed velocities. Some galaxy matches are members of galaxy groups. From these multiple galaxy matches, 714 (16%) have confirmed optical velocities and a further 258 (6%) galaxies are without confirmed velocities. For 481 (11%), multiple galaxies are present but no single optical counterpart can be chosen and 216 (5%) have no obvious optical galaxy present. Most of these 'blank fields' are in crowded fields along the Galactic plane or have high extinctions. Isolated 'Dark galaxy' candidates are investigated using an extinction cut of ABj < 1 mag and the blank fields category. Of the 3692 galaxies with an ABj extinction < 1 mag, only 13 are also blank fields. Of these, 12 are eliminated either with follow-up Parkes observations or are in crowded fields. The remaining one has a low surface brightness optical counterpart. Hence, no isolated optically dark galaxies have been found within the limits of the Hipass survey.Comment: 10 pages, 15 figures, MNRAS (in press

Doing good buffers against feeling bad: Prosocial impact compensates for negative task and self-evaluations

Although evidence suggests that negative task and self-evaluations are associated with emotional exhaustion, little research has examined factors that buffer against these affects. We propose that perceived prosocial impact, the experience of helping others, compensates for negative task and self-evaluations by focusing attention on positive outcomes for others. In Study 1, perceived prosocial impact attenuated the associations of low intrinsic motivation and core self-evaluations with emotional exhaustion among professional fundraisers. Study 2 replicated these results among public sanitation employees and extended them to supervisor performance ratings. Mediated moderation analyses indicated that by protecting against emotional exhaustion, perceived prosocial impact compensated for low intrinsic motivation and core self-evaluations to predict higher performance ratings. Our studies extend theory and research on burnout, helping, and citizenship

Simulated Effects of Recruitment Variability, Exploitation, and Reduced Habitat Area on the Muskellunge Population in Shoepack Lake, Voyageurs National Park, Minnesota

The genetically unique population of muskellunge Esox masquinongy inhabiting Shoepack Lake in Voyageurs National Park, Minnesota, is potentially at risk for loss of genetic variability and long-term viability. Shoepack Lake has been subject to dramatic surface area changes from the construction of an outlet dam by beavers Castor canadensis and its subsequent failure. We simulated the long-term dynamics of this population in response to recruitment variation, increased exploitation, and reduced habitat area. We then estimated the effective population size of the simulated population and evaluated potential threats to long-term viability, based on which we recommend management actions to help preserve the long-term viability of the population. Simulations based on the population size and habitat area at the beginning of a companion study resulted in an effective population size that was generally above the threshold level for risk of loss of genetic variability, except when fishing mortality was increased. Simulations based on the reduced habitat area after the beaver dam failure and our assumption of a proportional reduction in population size resulted in an effective population size that was generally below the threshold level for risk of loss of genetic variability. Our results identified two potential threats to the long-term viability of the Shoepack Lake muskellunge population, reduction in habitat area and exploitation. Increased exploitation can be prevented through traditional fishery management approaches such as the adoption of no-kill, barbless hook, and limited entry regulations. Maintenance of the greatest possible habitat area and prevention of future habitat area reductions will require maintenance of the outlet dam built by beavers. Our study should enhance the long-term viability of the Shoepack Lake muskellunge population and illustrates a useful approach for other unique populations