Galactic Chemical Evolution and the abundances of lithium, beryllium and boron

A LiBeB evolution model including Galactic Cosmic Ray nucleosynthesis, the $\nu$-process, novae, AGB and C-stars is presented. We have included Galactic Cosmic Ray Nucleosynthesis (GCRN) in a complete Chemical Evolution Model that takes into account 76 stable isotopes from hydrogen to zinc. Any successful LiBeB evolution model should also be compatible with other observational constraints like the age-metallicity relation, the G-dwarf distribution or the evolution of other elements. At the same time, we have checked how different would be a model that took into account the last observations by Wakker et al. (1999) of metal-enriched clouds falling onto the disk, from a primordial infall model.Comment: 2 pages, 2 figures. To appear in `Cosmic Evolution' Conference at IAp, Paris 13-17 Nov 200

Evaluating the Impact of Ethephon on Bud Break and Delayed Pruning on Cluster Count in Winegrapes

Grapes are an important crop in the United States with most of their value towards winegrapes. Frost and freeze events are a major weather-related problem, and late spring freeze/frost can cause considerable yield loss for growers, thus affecting the wine industry. Although there are numerous methods of frost protection, many are impractical or are not very effective. This project focused on the use of ethephon as a tool to prevent late spring frost damage by delaying bud break in grapes, and the impact of delayed pruning on vine fruitfulness (cluster count). Ethephon treatments consisted of applying ethephon as a spray on dormant canes at a rate of 145 mg L^-1 (low) and 291 mg L^-1 (high) at five different timings: November, December, January, February, and March. The greatest delay in bud break was observed in vines treated with ethephon in January. The high rate was more effective than the low rate and highly dependent on cultivar, except for low rate applications in November which showed adverse effects by advancing bud break during the spring. The results of this study suggest that the use of ethephon as a tool to delay bud break requires further research before it can be recommended. In the delayed pruning study, eight cultivars and numbered selections were subjected to final pruning at 50% bud break and final pruning at 3 weeks after 50% bud break. Across the six cultivars and numbered selections under study, a 19-80% decrease in cluster count was observed. However, vine vigor as determined by shoot length and iii shoot diameter was not significantly influenced by the delayed pruning treatments. These results suggest that pruning three weeks after bud break can be detrimental to grape yield and is not recommended as a means to avoid or mitigate late spring frost damage

Influence of surface anisotropy on the magnetization reversal of nanoparticles

The influence of surface anisotropy on the magnetization processes of maghemite nanoparticles with ellipsoidal shape is studied by means of Monte Carlo simulations. Radial surface anisotropy is found to favor the formation of hedgehog-like spin structures that become more stable as the surface anisotropy constant at the surface $k_S$ is increased form the value at the core. We have studied the change in the low temperature hysteresis loops with the particle aspect ratio and with $k_S$, finding a change in the magnetization reversal mode as $k_S$ or the particle elongation is increased.Comment: Contribution to SCM2004 (2nd Seeheim Conference on Magnetism), to be published in Physica Status Solidi A. 4 pages, 2 figure

Year 1 report for ‘Conserving Texas Biodiversity: Status, Trends, and Conservation Planning for Fishes of Greatest Conservation Need’

State Wildlife Grant Program, grant TX T-106-1 (CFDA# 15.634), Contract No. 459125 UTA14-001402Substantive progress was made on all major Project Activities in this first year: Activity 1. Coordinate and Facilitate Science and Conservation Actions for Conserving Texas Biodiversity - We expanded and strengthened UT-TPWD coordination, transitioning the relationship between these partners into a much more collaborative one than was previously realized. The flow of data between TPWD and the Fishes of Texas Project (supported in part by this project) has become much more bi-directional. Many newly collected TPWD specimens, agency databases, legacy data products and reports, and feedback from resource managers are now beginning to contribute substantively to growth and diversity (now including non-specimen-vouchered records) of data served through the FoTX Project’s websites. Work on cleaning and normalizing of FoTX’s online specimen-vouchered database continued, and the updated FoTX occurrence and distribution data are being actively used. Most recently they were used by this project, together with expert (TPWD, UT and others’) opinions, to develop recommendations on conservation status of native fishes of Texas’ Species of Greatest Conservation Need for TPWD’s consideration in anticipated updates to the Texas Conservation Action Plan. Within two months of this report, a new and substantially larger and improved version of the FoTX website/database and related collection of images, field notes, and ancillary datasets, will be formally announced. Activity 2. Identify Priority Geographic Management Units for Conserving Fishes of Greatest Conservation Need - We used FoTX data in a systematic conservation area prioritization analysis to identify Native Fish Conservation Areas (NFCAs) for large portions of Texas where such comprehensive planning had not been previously carried out. Updated and new FoTX data for all Texas fish Species of Greatest Conservation Need (SGCN) were used in production of newly improved Species Distribution Models for input into this planning process, and the results of the planning exercise have already been integrated by TPWD into management prioritizations of both those species and the resultant NFCAs. Activity 3. Develop Monitoring and Conservation Plans for Native Fish Conservation Areas - Monitoring and conservation plans were delivered to TPWD for all NFCAs identified in Activity 2. Activity 4. Conduct Field-Based Surveys Detailed Biodiversity Assessments (i.e. Bioblitzing), and Citizen-Based Monitoring - Field surveys with detailed biodiversity assessments (“bioblitzes”) and citizen-based monitoring were conducted in three areas selected collaboratively by TPWD and FoTX Project staff from within the identified NFCAs: Nueces River headwaters, Big Cypress Bayou basin, and Village Creek basin. Along with this field effort, FoTX Project staff developed and circulated guidelines and best practices, and provided training for citizen-based monitoring that leverages iNaturalist for capture and reporting of photo-vouchered occurrence records in ways that will help assure scientifically useful data are obtained. All specimens acquired during these field efforts, and from many other routine specimen acquisitions from across the state (1845 total records/jars of specimens), were cataloged in the UT Fish Collection database. From there, these new records will soon be fed into GBIF, VertNet, FishNet2 and other major online data aggregators, including the online Fishes of Texas database.Texas Parks and Wildlife Department; U.S. Fish and Wildlife ServiceIntegrative Biolog

Student Expectations Regarding Online Learning: Implications For Distance Learning Programs

What are student expectations in a traditional course versus a distance learning course? The authors analyze student course selection and expected outcomes from data collected in an undergraduate marketing course at a public university in the Northeast. Key findings reveal that students generally have a favorable predisposition towards online coursework despite their beliefs that online courses require more work and have lower learning outcomes. Further, this case study provides an initial step in better understanding student expectations in online courses as well as in the traditional classroom

Modulation of release kinetics by plasma polymerization of ampicillin-loaded ß-TCP ceramics

Beta-tricalcium phosphate (ß-TCP) bioceramics are employed in bone repair surgery. Their local implantation in bone defects puts them in the limelight as potential materials for local drug delivery. However, obtaining suitable release patterns fitting the required therapeutics is a challenge. Here, plasma polymerization of ampicillin-loaded ß-TCP is studied for the design of a novel antibiotic delivery system. Polyethylene glycol-like (PEG-like) coating of ß-TCP by low pressure plasma polymerization was performed using diglyme as precursor, and nanometric PEG-like layers were obtained by simple and double plasma polymerization processes. A significant increase in hydrophobicity, and the presence of plasma polymer was visible on the surface by SEM and quantified by XPS. As a main consequence of the plasma polymerisation, the release kinetics were successfully modified, avoiding burst release, and slowing down the initial rate of release leading to a 4.5¿h delay in reaching the same antibiotic release percentage, whilst conservation of the activity of the antibiotic was simultaneously maintained. Thus, plasma polymerisation on the surface of bioceramics may be a good strategy to design controlled drug delivery matrices for local bone therapiesPeer ReviewedPostprint (author's final draft