Probing the superconducting ground state of the rare-earth ternary boride superconductors RRRuB2_2 (RR = Lu,Y) using muon-spin rotation and relaxation

The superconductivity in the rare-earth transition metal ternary borides $R$RuB$_2$ (where $R$ = Lu and Y) has been investigated using muon-spin rotation and relaxation. Measurements made in zero-field suggest that time-reversal symmetry is preserved upon entering the superconducting state in both materials; a small difference in depolarization is observed above and below the superconducting transition in both compounds, however this has been attributed to quasistatic magnetic fluctuations. Transverse-field measurements of the flux-line lattice indicate that the superconductivity in both materials is fully gapped, with a conventional s-wave pairing symmetry and BCS-like magnitudes for the zero-temperature gap energies. The electronic properties of the charge carriers in the superconducting state have been calculated, with effective masses $m^*/ m_\mathrm{e} =$ $9.8\pm0.1$ and $15.0\pm0.1$ in the Lu and Y compounds, respectively, with superconducting carrier densities $n_\mathrm{s} =$ ($2.73\pm0.04$) $\times 10^{28}$ m$^{-3}$ and ($2.17\pm0.02$) $\times 10^{28}$ m$^{-3}$. The materials have been classified according to the Uemura scheme for superconductivity, with values for $T_\mathrm{c}/T_\mathrm{F}$ of $1/(414\pm6)$ and $1/(304\pm3)$, implying that the superconductivity may not be entirely conventional in nature.Comment: 8 pages, 8 figure

Do Complexity Measures of Frontal EEG Distinguish Loss of Consciousness in Geriatric Patients Under Anesthesia?

While geriatric patients have a high likelihood of requiring anesthesia, they carry an increased risk for adverse cognitive outcomes from its use. Previous work suggests this could be mitigated by better intraoperative monitoring using indexes defined by several processed electroencephalogram (EEG) measures. Unfortunately, inconsistencies between patients and anesthetic agents in current analysis techniques have limited the adoption of EEG as standard of care. In attempts to identify new analyses that discriminate clinically-relevant anesthesia timepoints, we tested 1/f frequency scaling as well as measures of complexity from nonlinear dynamics. Specifically, we tested whether analyses that characterize time-delayed embeddings, correlation dimension (CD), phase-space geometric analysis, and multiscale entropy (MSE) capture loss-of-consciousness changes in EEG activity. We performed these analyses on EEG activity collected from a traditionally hard-to-monitor patient population: geriatric patients on beta-adrenergic blockade who were anesthetized using a combination of fentanyl and propofol. We compared these analyses to traditional frequency-derived measures to test how well they discriminated EEG states before and after loss of response to verbal stimuli. We found spectral changes similar to those reported previously during loss of response. We also found significant changes in 1/f frequency scaling. Additionally, we found that our phase-space geometric characterization of time-delayed embeddings showed significant differences before and after loss of response, as did measures of MSE. Our results suggest that our new spectral and complexity measures are capable of capturing subtle differences in EEG activity with anesthesia administration-differences which future work may reveal to improve geriatric patient monitoring

Alfalfa baleage preparation and quality

Last updated: 6/1/200

Ultrasonic Detection of a Plastic Hinge in Bolted Timber Connections

Connections between structural members are critical elements that typically govern the performance of structural systems; hence, techniques for monitoring the condition of connections are needed to provide early warning of structural damage. Plastic hinge formation in fasteners frequently occurs in timber connections when the yield capacity is exceeded. An innovative pulse echo testing technique was developed for detecting the formation of a plastic hinge in bolted timber connections and estimating the associated magnitude of connection displacement. A shift in overall signal centroid proved to be the best flTedictor of plastic hinge formation, with a coefficient of determination (R2) of 0.9. As the plastic hinge angle increased, the signal centroid shifted to the right since a higher proportion of pulse energy was forced to undergo multiple transverse wave reflections caused by the deformed geometry of the bolt. Because the determination of a shift in signal centroid requires the availability of prior test information for the initially undeformed fastener, an alternate linear relationship between echo amplitude ratios and plastic hinge formation was also proposed with an adjusted R2 of 0.87. This three parameter regression equation had the advantages of requiring no prior testing information and eliminating ambiguity in signal analysis associated with selection of echo start and end points. Plastic hinge formation was correlated with connection ductility, magnitude of connection overload and energy based measures of connection damage to assess residual connection capacity

Influence of Breedtype on Adrenal Responsiveness to ACTH in Beef Steers

Last updated: 6/12/200

The XBabelPhish MAGE-ML and XML Translator

<p>Abstract</p> <p>Background</p> <p>MAGE-ML has been promoted as a standard format for describing microarray experiments and the data they produce. Two characteristics of the MAGE-ML format compromise its use as a universal standard: First, MAGE-ML files are exceptionally large – too large to be easily read by most people, and often too large to be read by most software programs. Second, the MAGE-ML standard permits many ways of representing the same information. As a result, different producers of MAGE-ML create different documents describing the same experiment and its data. Recognizing all the variants is an unwieldy software engineering task, resulting in software packages that can read and process MAGE-ML from some, but not all producers. This Tower of MAGE-ML Babel bars the unencumbered exchange of microarray experiment descriptions couched in MAGE-ML.</p> <p>Results</p> <p>We have developed XBabelPhish – an XQuery-based technology for translating one MAGE-ML variant into another. XBabelPhish's use is not restricted to translating MAGE-ML documents. It can transform XML files independent of their DTD, XML schema, or semantic content. Moreover, it is designed to work on very large (> 200 Mb.) files, which are common in the world of MAGE-ML.</p> <p>Conclusion</p> <p>XBabelPhish provides a way to inter-translate MAGE-ML variants for improved interchange of microarray experiment information. More generally, it can be used to transform most XML files, including very large ones that exceed the capacity of most XML tools.</p

Influence of Season of Birth on Reproductive Development of Brahman Bulls

Last updated: 6/12/200

Olefin Hydroarylation Catalyzed by (Pyridyl-Indolate)Pt(II) Complexes: Catalytic Efficiencies and Mechanistic Aspects

A series of Pt(II) complexes of the type (N–N)PtPh(SR_2) (N–N = 2,2′-pyridyl-indolate) were prepared, and their performance as catalysts for the hydroarylation of olefins was assessed. Evidence that the catalysis is homogeneous and is Pt-mediated is provided by control experiments with added hindered base (2,6-di-tert-butyl-4-methylpyridine) and Hg(0). Two potential catalytic intermediates, (^tBuPyInd)PtPh(C_2H_4) and (^tBuPyInd)Pt(CH_2CH_2Ph)(C_2H_4), were synthesized, and their catalytic efficacy was explored. Additionally, decomposition and deactivation pathways, including styrene formation via β-hydride elimination and ligand reductive demetalation, were identified