Birds of the Oak Lake Field Station

A preliminary check-off list of avian species was compiled using regional field guides shortly after the establishment of the field station (Northern Plains Biological Field Station Committee 1987). While this list has been a useful reference, little observational data have been available to establish accuracy. Field observation data were collected to verify this checklist and establish a baseline inventory of resident and migratory avifauna for the station. Obse1vations were collected Janua1y 1994 through August 1996 during bird watching expeditions and research activities. In addition, formal bird counts were conducted at eight sites along 100 m transects of 30 m fixed width from 16 May to 23 June 23 1995. Birds were tallied, based upon sight and call, along each transect on twelve dates

Patterns in Avian Community Structure and Non-Point Source Disturbance Potential Along the Land-Water Interface of a Prairie Pothole Lake

This study was conducted to test the hypothesis that bird community structure varies significantly between areas which are prone versus not prone to disturbance within the land-water interface of a prairie lake. On-site assessment of land cover and a Geographic Information System (GIS) with coverages of slope, soil erodability, soil hydrologic group and drainages were used to delineate sites prone and not prone to non-point source disturbance. Habitat and community attributes were examined within these site classes during the summer of 1995. While habitat differences between classes (prone and not prone) were inconclusive, results of avian community analyses indicated that sites prone to disturbance had significantly higher average densities (69 individuals/ha vs. 56), species richness (10.9 vs. 8.1 species) and diversity (H’=2.05 vs. 1.72) than sites not prone to disturbance. These results are consistent with observations of other ecological communities exposed to intermediate levels of disturbance. Furthermore, these results suggest a relationship between GIS generated nonpoint source disturbance potential and ecological communities within the landwater interface

Association of Resistance Exercise, Independent of and Combined With Aerobic Exercise, With the Incidence of Metabolic Syndrome.

OBJECTIVE: To determine the association of resistance exercise, independent of and combined with aerobic exercise, with the risk of development of metabolic syndrome (MetS). PATIENTS AND METHODS: The study cohort included adults (mean ± SD age, 46±9.5 years) who received comprehensive medical examinations at the Cooper Clinic in Dallas, Texas, between January 1, 1987, and December, 31, 2006. Exercise was assessed by self-reported frequency and minutes per week of resistance and aerobic exercise and meeting the US Physical Activity Guidelines (resistance exercise ≥2 d/wk; aerobic exercise ≥500 metabolic equivalent min/wk) at baseline. The incidence of MetS was based on the National Cholesterol Education Program Adult Treatment Panel III criteria. We used Cox regression to generate hazard ratios (HRs) and 95% CIs. RESULTS: Among 7418 participants, 1147 (15%) had development of MetS during a median follow-up of 4 years (maximum, 19 years; minimum, 0.1 year). Meeting the resistance exercise guidelines was associated with a 17% lower risk of MetS (HR, 0.83; 95% CI, 0.73-0.96; P=.009) after adjusting for potential confounders and aerobic exercise. Further, less than 1 hour of weekly resistance exercise was associated with 29% lower risk of development of MetS (HR, 0.71; 95% CI, 0.56-0.89; P=.003) compared with no resistance exercise. However, larger amounts of resistance exercise did not provide further benefits. Individuals meeting both recommended resistance and aerobic exercise guidelines had a 25% lower risk of development of MetS (HR, 0.75; 95% CI, 0.63-0.89; P<.001) compared with meeting neither guideline. CONCLUSION: Participating in resistance exercise, even less than 1 hour per week, was associated with a lower risk of development of MetS, independent of aerobic exercise. Health professionals should recommend that patients perform resistance exercise along with aerobic exercise to reduce MetS

Population-level effect of HSV-2 therapy on the incidence of HIV in sub-Saharan Africa.

BACKGROUND: Herpes simplex virus type 2 (HSV-2) infection increases acquisition and transmission of HIV, but the results of trials measuring the impact of HSV-2 therapy on HIV genital shedding and HIV acquisition are mixed, and the potential impact of HSV-2 therapy on the incidence of HIV at the population level is unknown. METHODS: The effects of episodic and suppressive HSV-2 therapy were simulated using the individual-level model STDSIM fitted to data from Cotonou, Benin (relatively low HIV prevalence) and Kisumu, Kenya (high HIV prevalence). Clinician- and patient-initiated episodic therapy, started when symptomatic, were assumed to reduce ulcer duration. Suppressive therapy, given regardless of symptoms, was also assumed to reduce ulcer frequency and HSV-2 infectiousness. RESULTS: Clinician-initiated episodic therapy in the general population had almost no effect on the incidence of HIV. The impact of patient-initiated therapy was higher because of earlier treatment initiation, but still low (20% in the long term. Impact was increased in both cities by also treating a proportion of their clients. Long-term suppressive therapy with high coverage in the general population could reduce HIV incidence by more than 30%. CONCLUSIONS: These results show that HSV-2 therapy could potentially have a population-level impact on the incidence of HIV, especially in more concentrated epidemics. However, a substantial impact requires high coverage and long duration therapy, or very high symptom recognition and treatment-seeking behaviour

High-resolution spectroscopy of the R Coronae Borealis and Other Hydrogen Deficient Stars

High-resolution spectroscopy is a very important tool for studying stellar physics, perhaps, particularly so for such enigmatic objects like the R Coronae Borealis and related Hydrogen deficient stars that produce carbon dust in addition to their peculiar abundances. Examples of how high-resolution spectroscopy is used in the study of these stars to address the two major puzzles are presented: (i) How are such rare H-deficient stars created? and (ii) How and where are the obscuring soot clouds produced around the R Coronae Borealis stars?Comment: 16 pages, 9 figures, Astrophysics and Space Science Proceedings, Springer-Verlag, Berlin, 201

Stress in nurses : stress-related affect and its determinants examined over the nursing day

Peer reviewedPostprin

Modeling the cumulative genetic risk for multiple sclerosis from genome-wide association data

Background: Multiple sclerosis (MS) is the most common cause of chronic neurologic disability beginning in early to middle adult life. Results from recent genome-wide association studies (GWAS) have substantially lengthened the list of disease loci and provide convincing evidence supporting a multifactorial and polygenic model of inheritance. Nevertheless, the knowledge of MS genetics remains incomplete, with many risk alleles still to be revealed. Methods: We used a discovery GWAS dataset (8,844 samples, 2,124 cases and 6,720 controls) and a multi-step logistic regression protocol to identify novel genetic associations. The emerging genetic profile included 350 independent markers and was used to calculate and estimate the cumulative genetic risk in an independent validation dataset (3,606 samples). Analysis of covariance (ANCOVA) was implemented to compare clinical characteristics of individuals with various degrees of genetic risk. Gene ontology and pathway enrichment analysis was done using the DAVID functional annotation tool, the GO Tree Machine, and the Pathway-Express profiling tool. Results: In the discovery dataset, the median cumulative genetic risk (P-Hat) was 0.903 and 0.007 in the case and control groups, respectively, together with 79.9% classification sensitivity and 95.8% specificity. The identified profile shows a significant enrichment of genes involved in the immune response, cell adhesion, cell communication/ signaling, nervous system development, and neuronal signaling, including ionotropic glutamate receptors, which have been implicated in the pathological mechanism driving neurodegeneration. In the validation dataset, the median cumulative genetic risk was 0.59 and 0.32 in the case and control groups, respectively, with classification sensitivity 62.3% and specificity 75.9%. No differences in disease progression or T2-lesion volumes were observed among four levels of predicted genetic risk groups (high, medium, low, misclassified). On the other hand, a significant difference (F = 2.75, P = 0.04) was detected for age of disease onset between the affected misclassified as controls (mean = 36 years) and the other three groups (high, 33.5 years; medium, 33.4 years; low, 33.1 years). Conclusions: The results are consistent with the polygenic model of inheritance. The cumulative genetic risk established using currently available genome-wide association data provides important insights into disease heterogeneity and completeness of current knowledge in MS genetics

Dynamic Modelling under Uncertainty: The Case of Trypanosoma brucei Energy Metabolism

Kinetic models of metabolism require detailed knowledge of kinetic parameters. However, due to measurement errors or lack of data this knowledge is often uncertain. The model of glycolysis in the parasitic protozoan Trypanosoma brucei is a particularly well analysed example of a quantitative metabolic model, but so far it has been studied with a fixed set of parameters only. Here we evaluate the effect of parameter uncertainty. In order to define probability distributions for each parameter, information about the experimental sources and confidence intervals for all parameters were collected. We created a wiki-based website dedicated to the detailed documentation of this information: the SilicoTryp wiki (http://silicotryp.ibls.gla.ac.uk/wiki/Glycolysis). Using information collected in the wiki, we then assigned probability distributions to all parameters of the model. This allowed us to sample sets of alternative models, accurately representing our degree of uncertainty. Some properties of the model, such as the repartition of the glycolytic flux between the glycerol and pyruvate producing branches, are robust to these uncertainties. However, our analysis also allowed us to identify fragilities of the model leading to the accumulation of 3-phosphoglycerate and/or pyruvate. The analysis of the control coefficients revealed the importance of taking into account the uncertainties about the parameters, as the ranking of the reactions can be greatly affected. This work will now form the basis for a comprehensive Bayesian analysis and extension of the model considering alternative topologies

Impact of shortened crop rotation of oilseed rape on soil and rhizosphere microbial diversity in relation to yield decline

Oilseed rape (OSR) grown in monoculture shows a decline in yield relative to virgin OSR of up to 25%, but the mechanisms responsible are unknown. A long term field experiment of OSR grown in a range of rotations with wheat was used to determine whether shifts in fungal and bacterial populations of the rhizosphere and bulk soil were associated with the development of OSR yield decline. The communities of fungi and bacteria in the rhizosphere and bulk soil from the field experiment were profiled using terminal restriction fragment length polymorphism (TRFLP) and sequencing of cloned internal transcribed spacer regions and 16S rRNA genes, respectively. OSR cropping frequency had no effect on rhizosphere bacterial communities. However, the rhizosphere fungal communities from continuously grown OSR were significantly different to those from other rotations. This was due primarily to an increase in abundance of two fungi which showed 100% and 95% DNA identity to the plant pathogens Olpidium brassicae and Pyrenochaeta lycopersici, respectively. Real-time PCR confirmed that there was significantly more of these fungi in the continuously grown OSR than the other rotations. These two fungi were isolated from the field and used to inoculate OSR and Brassica oleracea grown under controlled conditions in a glasshouse to determine their effect on yield. At high doses, Olpidium brassicae reduced top growth and root biomass in seedlings and reduced branching and subsequent pod and seed production. Pyrenochaeta sp. formed lesions on the roots of seedlings, and at high doses delayed flowering and had a negative impact on seed quantity and quality

Sporormiella as a tool for detecting the presence of large herbivores in the Neotropics

The reliability of using the abundance of Sporormiella spores as a proxy for the presence and abundance of megaherbivores was tested in southern Brazil. Mud-water interface samples from nine lakes, in which cattle-use was categorized as high, medium, or low, were assayed for Sporormiella representation. The sampling design allowed an analysis of both the influence of the number of animals using the shoreline and the distance of the sampling site from the nearest shoreline. Sporormiella was found to be a reliable proxy for the presence of large livestock. The concentration and abundance of spores declined from the edge of the lake toward the center, with the strongest response being in sites with high livestock use. Consistent with prior studies in temperate regions, we find that Sporormiella spores are a useful proxy to study the extinction of Pleistocene megafauna or the arrival of European livestock in Neotropical landscapes