The eclipsing, double-lined, Of supergiant binary Cyg OB2-B17

Massive, eclipsing, double-lined, spectroscopic binaries are not common but are necessary to understand the evolution of massive stars as they are the only direct way to determine stellar masses. They are also the progenitors of energetic phenomena such as X-ray binaries and gamma-ray bursts. We present a photometric and spectroscopic analysis of the candidate binary system Cyg OB2-B17 to show that it is indeed a massive evolved binary. We utilise V band and white-light photometry to obtain a light curve and period of the system, and spectra at different resolutions to calculate preliminary orbital parameters and spectral classes for the components. Our results suggest that B17 is an eclipsing, double-lined, spectroscopic binary with a period of 4.0217+/-0.0004 days, with two massive evolved components with preliminary classifications of O7 and O9 supergiants. The radial velocity and light curves are consistent with a massive binary containing components with similar luminosities, and in turn with the preliminary spectral types and age of the association.Comment: 10 pages, 10 figures (1 degraded), accepted for publication in Astronomy and Astrophysic

The Willamette Valley (Oregon) Prairie Plant Trait Dataset

The Willamette Valley (Oregon) Prairie Plant Trait Dataset is a compilation of plant traits of species important in upland prairies, wetland prairies, vernal pools, and emergent wetlands, and in the restoration of prairies and wetlands of the Willamette Valley of Oregon. These species are also found widely throughout the Pacific Northwest. The dataset contains more than 6600 data points on 187 species. Three types of plant trait data are included in the dataset: quantitative, categorical, and text. Sources of plant trait data include direct measurements in the field or in the laboratory, or gathered from the published literature, including local floras, references books, and databases. Laboratory measurements include measurements of plant growth under standardized growth chamber conditions. The use of standardized conditions allows integration of results with those in the scientific literature. Standardized growth chamber conditions include specifications for germination media, transfer of germinates, pot size, growing media, nutrient solutions, growing illumination and temperatures, and dates of harvest. Growth chamber procedures followed the general recommendations of the Integrated Screening Programme (Hendry, G.A.F. and Grime, J.P. (eds) 1993. Methods in Comparative Plant Ecology: A Laboratory Manual. Chapman and Hall, London)

FlyBase: integration and improvements to query tools

FlyBase (http://flybase.org) is the primary resource for molecular and genetic information on the Drosophilidae. The database serves researchers of diverse backgrounds and interests, and offers several different query tools to provide efficient access to the data available and facilitate the discovery of significant relationships within the database. Recently, FlyBase has developed Interactions Browser and enhanced GBrowse, which are graphical query tools, and made improvements to the search tools QuickSearch and QueryBuilder. Furthermore, these search tools have been integrated with Batch Download and new analysis tools through a more flexible search results list, providing powerful ways of exploring the data in FlyBase

The Wilson Effective K\"ahler Potential For Supersymmetric Nonlinear Sigma Models

Renormalization group methods are used to determine the evolution of the low energy Wilson effective action for supersymmetric nonlinear sigma models in four dimensions. For the case of supersymmetric $CP^{(N-1)}$ models, the K\"ahler potential is determined exactly and is shown to exhibit a nontrivial ultraviolet fixed point in addition to a trivial infrared fixed point. The strong coupling behavior of the theory suggests the possible existence of additional relevant operators or nonperturbative degrees of freedom.Comment: 9 pages, LaTeX, 1 eps figur

Effect of a Patient-Centered Phone Call by a Clinical Officer at Time of HIV Testing on Linkage to Care in Rural Kenya.

In a randomized controlled trial, we tested whether a structured, patient-centered phone call from a clinical officer after HIV testing improved linkage to/re-engagement in HIV care. Among 130 HIV-positive persons, those randomized to the phone call were significantly more likely to link to care by 7 and 30 days (P = .04)

Promoting regeneration of native species In Willamette Valley upland prairies

Prepared for US Fish and Wildlife Service Western Oregon NWR Complex and Oregon Natural Heritage Program Portland, Oregon.Native prairies of the Willamette Valley are considered among the rarest of Oregon’s ecosystems and are in critical need of conservation. Management strategies for increasing the abundance of native species are urgently needed, particularly those strategies that promote the regeneration of native species from seed. The focus of this investigation was to address this need. The general approach was to sow seeds of native species into experimental field plots, which had been burned once, burned repeatedly, mowed, or unmanaged at three sites at Baskett Slough National Wildlife Refuge. Seedling numbers were then counted one growing season after sowing. To investigate mechanisms for the regeneration responses of species to management treatments, selected abiotic and biotic factors potentially important for seed regeneration were measured in the field plots. Seedling establishment rates in unmanaged plots were relatively small, averaging 9.7% for all three sites. Only one species, Danthonia californica, showed a positive response to the mowing treatment. Of the 13 species sowed in the burn plots, six species (Bromus carinatus, Elymus glacus, Festuca roemeri/rubra, Clarkia quadrivulera, Prunella vulgaris, Sidalcea campestris) had significant more seedlings in the burn plots compared to the unmanaged plots. Seedling establishment of two species, Danthonia californica and Potentilla gracilis, was significantly lower with burn treatments. The other five species showed no significant responses to the burn treatments: Carex tumicola, Calochortus tolmiei, Zygadensus venenosus, Balsamorhiza deltoidea, and Agoseris grandilflora. The strongest fire effects were generally in plots that had been burned only once, rather than plots burned more than once. Abundance of litter and vegetation were the factors that were most often related, both positively and negatively, with seedling establishment rates. Based on the results of this investigation, prescribed burning, rather than mowing, is a more viable management option to promote regeneration of native species from seed in upland prairies. However, prescribed burning must be used with caution as it can reduce seedling establishment rates for some species. Sowing seeds in unmanaged sites is an option, but sowing rates need to be high to compensate for the small seedling establishment rates in unmanaged prairies.Keywords: Fire, Conservation, Habitat management, Habitat restoration, Native species, Native prairie, Seedling establishment, Regeneration ecology, Willamette River Valley (Or.), Upland prairie, Germinatio

Increasing the abundance of rare native wetland prairie species

Native prairies of the Willamette Valley are considered among the rarest of Oregon’s ecosystems and are in critical need of conservation. Management strategies for increasing the abundance of native species are urgently needed, particularly those strategies that promote the regeneration of native species from seed. Fire may be an important factor in promoting regeneration of native species from seed because of its historical role in maintaining the prairie landscape. The study objectives were (1) to determine the effect of prescribed burning on regeneration of native species from seed, and (2) to establish predictive relationships between easily measured plant traits and seedling establishment rates in the field. The general approach was to sow seeds of target wetland prairie species during the fall into experimental field plots already established at the Danebo Wetland, Eugene, OR. Seedling establishment rates were then compared between burned and unburned plots the following spring. To establish predictive relationships these seedling establishment rates were related to selected seed and seedling traits measured under laboratory conditions. Overall seedling establishment rates showed no significant differences between burned (7.0%) and unburned plots (8.7%), although for the seven species showing positive responses to prescribed burning, the increase was approximately doubled in the burned plots. Burning significantly increased the seedling establishment rates of three species, Wyethia angustifolia, Grindelia integrifolia, and Danthonia californica. Seedling establishment significantly decreased with burning for one species, Sidalcea campestris. For three of the four endangered, threatened or rare species, Aster curtus, Horkelia congesta, and Sidalcea cusickii var. purpurea, seedling establishment rates were smaller in the burned plots compared to the unburned plots, although the differences were not significant. Lomatium bradshawii had no seedlings establish in either the burned or the unburned plots. Plant weight 7 days after germination was the best trait at predicting field seedling establishment rates for both the burned plots and the unburned plots, explaining a significant amount of variation in establishment rates: 70% for the burned plots and 45% for the unburned plots. This model could be used by managers to choose species for sowing in burned and unburned prairies or to estimate seeding rates at burned and unburned sites.Keywords: Conservation, Wetland prairie, Habitat restoration, Native species, Native prairie, Seedling establishment, Regeneration ecology, Willamette River Valley (Or.), Wetland, GerminationAward No. HE-P99-0020. Submitted to Bureau of Land Management, Coast Range Resource Area, Eugene, Oregon

Why pest plant control and native plant establishment failed : a restoration autopsy

Explaining restoration failure can be as important as touting success. We used a series of studies to understand the failure of techniques commonly used to restore wetland prairies in the Willamette Valley of western Oregon. Burning, fallowing, and solarization (covering tilled plots with plastic sheeting to heat the soil) had pronounced first-year effects on several individual species, but either did not reduce overall pest plant abundance or reduced the abundance of native species as well. The 34% overall plant cover in solarized plots was the only significant difference from the 60% cover present in control plots. All first-year responses essentially disappeared by the second year. These measures had little lasting effect on pest and other exotic plants because many survived treatment and resprouted. In addition, treatments had little effect on the number of seeds in the soil, leaving a pool of immediate and potential regeneration. Specific control measures of target plants, such as hand removal and repeat maintenance after initial treatments, should prove more successful. In a second study, three mixtures of native species sown into fallowing treatment plots had low emergence rates of 1% - 7%, despite high seed viability, and produced only 0% - 3% cover. Native species should be selected and sown at densities high enough to lead to significant numbers of surviving seedlings, especially in the face of competition from surviving pest plants