Landscape,Soil, and Plant Analysis of Japanese Stiltgrass (Microstegium vimineum) Invasion in the Piedmont Region,SC

Japanese stiltgrass (Microstegium vimineum), an exotic invasive plant, is native to Southeast Asia. This study was conducted to determine the chemical composition of Japanese stiltgrass as well as soil and landscape characteristics that correlate with invasion of Japanese stiltgrass around Lake Issaqueena in the upper Piedmont of South Carolina. Geographic Information Systems (GISs) and Light Detection and Ranging (LiDAR) were used to determine the spatial pattern of invasion with respect to the aspect, slope, canopy cover, soils, and distance to roads and trails. Japanese stiltgrass was distributed on both sides of Lake Issaqueena in Pacolet and Madison soil map units (Fine, kaolinitic, thermic Typic Kanhapludults) on the average slopes of 21%, but it was particularly common on the eastern shore of the lake in low-lying wet and shaded areas (mean canopy cover 51%). In addition, invasion by Japanese stiltgrass was correlated with the proximity to roads and trails. Plant tissue analysis revealed many differences in the distribution of macronutrients, macrominerals, and micronutrients in the leaves, stems, and roots of Japanese stiltgrass, although those differences were not always statistically significant. Concentrations of nitrogen (N), phosphorus (P), and calcium (Ca) were the highest in leaves while zinc (Zn) concentrations were the highest in stems and concentrations of magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe), and sodium (Na) tended to be higher in roots. Carbon (C), sulfur (S), and potassium (K) concentrations were generally higher in above-ground tissues versus roots. Soil chemical analysis revealed no statistical differences between control and invaded plots. Our findings suggest that watershed areas surrounding lakes may be particularly susceptible to the invasion of Japanese stiltgrass due to their microclimates, low-lying wet pathways for seed distribution and recreational uses.     

Inflammation and increased numbers of bacteria in the lower respiratory tract of horses within 6 to 12 hours of confinement with the head elevated

SUMMARY: Confinement of horses with their heads elevated for periods up to 24 hours was used to evaluate the extent and the effects of bacterial contamination of the equine lower respiratory tract. Significant (P < 0.05) increases in bacterial numbers (up to 10⁹ colony forming units/mL in transtracheal aspirate derived samples) occurred within 6 or 12 hours in most horses. Pasteurella/Actinobacillus spp and Streptococcus spp were most commonly isolated. Lowering of the head for 30 minutes every 6 hours to facilitate postural drainage did not prevent multiplication of organisms to levels equivalent to those achieved by horses where the head was elevated for 24 hours. When horses were released from confinement and heads were no longer maintained in an elevated position, clearance of accumulated secretions and bacteria occurred within 8 to 12 hours. Thus, confinement with the head elevated resulted in significant bacterial contamination and multiplication within the lower respiratory tract during a period often encountered in routine management procedures, such as transportation. The clearance of accumulated secretions occurred over a prolonged period after release from such confinement.     

Insulin sensitivity decreases with obesity, and lean cats with low insulin sensitivity are at greatest risk of glucose intolerance with weight gain

This study quantifies the effects of marked weight gain on glucose and insulin metabolism in 16 cats which increased their weight by an average of 44.2% over 10 months. Significantly, the development of feline obesity was accompanied by a 52% decrease in tissue sensitivity to insulin and diminished glucose effectiveness. In addition, glucose intolerance and abnormal insulin response occurred in some cats. An important finding was that normal weight cats with low insulin sensitivity and glucose effectiveness were at increased risk of developing impaired glucose tolerance with obesity. High basal insulin concentrations or low acute insulin response to glucose also independently increased the risk for developing impaired glucose tolerance. Male cats gained more weight relative to females and this, combined with their tendency to lower insulin sensitivity and higher insulin concentrations, may explain why male cats are at greater risk for diabetes. Results suggest an underlying predisposition for glucose intolerance in some cats, which is exacerbated by obesity. These cats may be more at risk of progressing to overt type 2 diabetes mellitus.     

Tibial plateau symmetry and the effect of osteophytosis on tibial plateau angle measurements

A novel technique was developed to estimate the caudal medial tibial plateau landmark in the face of osteophytosis to improve accuracy in tibial plateau angle measurements. Using this technique, tibial plateau angles were evaluated in 31 normal dogs before and 8 months after right cranial cruciate ligament transection. There was no significant difference in mean tibial plateau angle before or after induction of osteophytosis. Additionally, it was determined that 90% of dogs had a difference of =2 degrees between right and left tibial plateau angles, which was considered symmetrical.     

Summer cover crop impacts on soil percolation and nitrogen leaching from a winter corn field

The impacts of a leguminous summer cover crop (sunn hemp; Crotalaria juncea) on nitrogen leaching from a corn (Zea mays L.) field was evaluated by direct measurements of soil water content and nitrogen balance components, complemented by direct and inverse modeling as an exploratory tool to better understand water flow and nitrogen balances in the soil. Water and nitrogen inputs and outputs were measured during winter corn production in an experimental field located in the south Miami-Dade basin in southern Florida (USA). Data from the last two seasons (2001-2002 and 2002-2003) of a 4-year study are presented. The field was divided into six 0.13 ha plots. One-half of the plots were rotated with sunn hemp (CC plots) during the summer while the remaining plots were kept fallow (NC plots). Sweet corn management was uniform on all plots and followed grower recommended practices. A numerical model (WAVE) for describing water and agrochemical movement in the soil was used to simulate water and nitrogen balances in both types of plots during the corn seasons. The hydrodynamic component of WAVE was calibrated with soil water data collected continuously at three depths, which resulted in accurate soil water content predictions (coefficients of efficiency of 0.85 and 0.91 for CC and NC plots, respectively). Measured components of the nitrogen balance (corn yields, estimated nitrogen uptake, and soil organic nitrogen) were used to positively assess the quality of the nitrogen simulation results. Results of the modeled water balance indicate that using sunn hemp as a cover crop improved the soil physical conditions (increase in soil water retention) and subsequently enhanced actual crop evapotranspiration and reduced soil drainage. However, nitrogen simulation results suggest that, although corn nitrogen uptake and yields were slightly higher in the CC plots than in the NC plots, there were net increases of soil N content that resulted in increased N leaching to the shallow aquifer. Therefore, the use of sunn hemp as cover crop should be coupled with reductions in N fertilizer applied to the winter crop to account for the net increase in soil N content.     

Prevalence of lesions and body condition scores among female swine at slaughter

OBJECTIVE: To determine prevalence of foot lesions, dermatitis, shoulder lesions, mammary gland abnormalities, and visceral lesions, and body condition scores among culled female swine at slaughter. DESIGN: Observational study. ANIMALS: Culled gilts and sows killed during a 1-week period at a Midwest slaughterhouse. PROCEDURE: Carcasses were examined, and lesions were recorded. Body condition was scored on the basis of standard criteria. RESULTS: 58.9% (1,029/1,747) of the carcasses had foot lesions, 67.3% (1,178/1,751) had dermatitis, and 4.6% (80/1,751) had shoulder lesions. Body condition score was significantly associated with detection of dermatitis and shoulder lesions. Mean +/- SE number of teats (n = 1,432 carcasses) was 13.86 +/- 0.02. Mean numbers of normal-appearing teats in the left and right mammary chains were 6.57 +/- 0.02 and 6.58 +/- 0.02, respectively. Feet from 48% (688/1,433) of the carcasses were condemned. Visceral lesions were found in 48.8% (624/1,278) of the carcasses; of the carcasses with lesions, 412 (66%) had liver spots, and 268 (42.9%) had pneumonia. CLINICAL IMPLICATIONS: Lesions that potentially could have adversely affected production were found in a large percentage of culled gilts and sows at slaughter. Knowledge of lesions commonly found at slaughter may help direct changes in herd health programs.     

Bronchoalveolar lavage in horses: effect of exercise and repeated sampling on cytology

SUMMARY Bronchoalveolar lavage (BAL) was performed at weekly intervals in 10 Thoroughbred horses in race training (group 1) and in 4 rested horses (group 2) for 10 weeks. Lavages were continued on a weekly basis in 4 group 1 horses for an additional 9 weeks (group 3). Cytological analysis of samples included leukocyte counts, erythrocyte counts, differential leukocyte counts, and haemosiderophage score. The mean leukocyte concentration was significantly lower in group 1(92.1 ± 4.6 cells/μL) when compared with group 2 (133.5 ± 8.2 cells/μL), P = 0.037. The differential leukocyte data were not significantly different between groups. There was a large amount of variability in the percent-age of macrophages and lymphocytes in the differential counts over time with no obvious trends. The proportion of neutrophils demonstrated a tendency to decrease over time for both groups 1 and 2. Erythrocyte counts and haemosiderin scores were significantly higher in the exercising group than the rested horses. Neither exercise nor the technique itself evoked an inflammatory response in the BAL fluid.     

Scale for the phase diagram of quantum chromodynamics

Matter described by quantum chromodynamics (QCD), the theory of strong interactions, may undergo phase transitions when its temperature and the chemical potentials are varied. QCD at finite temperature is studied in the laboratory by colliding heavy ions at varying beam energies. We present a test of QCD in the nonperturbative domain through a comparison of thermodynamic fluctuations predicted in lattice computations with the experimental data of baryon number distributions in high-energy heavy ion collisions. This study provides evidence for thermalization in these collisions and allows us to find the crossover temperature between normal nuclear matter and a deconfined phase called the quark gluon plasma. This value allows us to set a scale for the phase diagram of QCD.     

Molecular Analysis of Local Potato Cultivars from Tenerife Island Using Microsatellite Markers

We have used 19 SSR markers to fingerprint 41 local potato cultivars from 10 locations of Tenerife Island. These varieties represent relicts of the early introductions originating from South America and have been characterised previously morphologically and ecophysiologically. The SSR primers generated a varying degree of polymorphisms. A total of 67 alleles were observed, 12 of them were present in all cultivars. Several accession and group specific alleles were detected. Similarity coefficients were computed from the molecular data and cluster analyses were performed. Generally, cultivar groups with identical or related common names showed the same SSR patterns or clustered closely together. According to the molecular patterns misleading or confounded names were evident for four accessions. The dendrogram clusters were generally in good agreement with previous classifications of the accessions as Solanum tuberosum subsp. andigena, S. tuberosum subsp. tuberosum and Solanum chaucha genotypes. However in four cases the molecular patterns showed discrepancies with previous species assignments suggesting the need for a more detailed and comparative study of these accessions.