Modeling and Characterization of a Novel, Low-Cost, Direct-Write Waveguide

Both the current long-term telecommunication trends toward optical networking and the recent growth in information bandwidth have pushed the necessity for improved optical communications. Our fabrication approach, which leverages our expertise in solid freeform fabrication in conjunction with sol-gel technology, has advantages over these other methods because of the inherent benefits of using a direct-write philosophy, such as design flexibility and minimal post-processing. However, fabrication of such novel optical components requires extensive knowledge of their light guidance capabilities. This paper will show the technical issues involved in both modeling and characterizing small optical components fabricated by locally densifying sol-gels in a modified directwrite process.Mechanical Engineerin

Differences between tree species in hydraulic press calibration of leaf water potential are correlated with specific leaf area

. To determine the usefulness of the J-14 Hydraulic Press (Campbell Scientific, Inc., Logan, Utah, U.S.A.) in estimating leaf water potential, we calibrated the J-14 Press against a Scholander-type pressure chamber for leaves of various tree species. The species tested were: Acer saccharum, Acer negundo, Acer rubrum. Populus tremuloides, Populus grandidentata, Quercus rubra , and Brassaia actinophylla (Schefflera). The regression calibrations were linear with standard errors about the regression less than 0.1 MPa. The regression equations for the four genera were significantly different, with the y- intercept increasing and the slope decreasing in order of decreasing specific leaf area (SLA). There were no significant differences between species of the calibration lines within the genera Acer and Populus. These data may indicate that leaves with lower SLA resist mechanical compression by the hydraulic press, causing the J-14 Press to be less sensitive to differences of leaf water potential. Therefore the J-14 Press is only a relative measure of leaf water status and does not measure leaf water potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73416/1/1365-3040.ep11591871.pd

Τhe role of surface energy in the apparent solubility of two different calcite crystal habits

The interplay between polymorphism and facet-specific surface energy on the dissolution of crystals is examined in this work. It is shown that, using cationic additives, it is possible to produce star-shaped calcite crystals at very high supersaturations. In crystallization processes following the Ostwald rule of stages these star-shaped crystals appear to have higher solubility than both their rhombohedral counterparts and needle-shaped aragonite crystals. The vapour pressures of vaterite, aragonite, star-shaped calcite and rhombohedral calcite crystals are measured using thermogravimetric analysis and the corresponding enthalpies of melting are obtained. Using inverse gas chromatography, the surface energy of the aforementioned crystals is measured as well and the surface energy of the main crystal facets is calculated. Combining the effect of facet-specific surface energies and the enthalpies of melting on a modified version of the classical solubility equation for regular solutions, it is proved that the star-shaped calcite crystals can indeed have higher apparent solubility than aragonitecrystals

Seasonal Association of Pediatric Functional Abdominal Pain Disorders and Anxiety

Objectives: Abdominal pain-related pediatric functional gastrointestinal disorders (AP-FGIDs) are defined by abdominal discomfort or pain that may provide obstacles to everyday activities, such as school attendance. It has been reported that AP-FGID symptoms may be reduced in summer, but it is unclear what drives this seasonal variation. This pilot study aimed to explore whether the seasonal variation in AP-FGID symptoms could be explained by various psychological and behavioral factors. Methods: Parents of children with AP-FGID symptoms completed online questionnaires on symptoms, anxiety, parental responses to pain, sleep, diet, and physical activity once during spring months and again in the summer months. Results: In a sample of 34 participants who completed both questionnaires, 22 reported improvements during the summer months. These participants reported a significantly higher seasonal decrease in anxiety than participants whose children's symptoms did not improve from spring to summer (mean decrease 2.21 vs 0.08, P = 0.017). Both groups reported equal improvements in sleep and decreased stress from spring to summer. Neither group experienced statistically significant seasonal change in physical activity or fruit, vegetables, dairy, or caffeine consumption. Conclusions: This study suggests that amelioration of gastrointestinal symptoms in pediatric patients with AP-FGID during summer months is associated with amelioration of anxiety in the same time period. It is not yet clear whether decreased anxiety is the cause or effect of decreased AP-FGID symptoms

Comparison of case note review methods for evaluating quality and safety in health care

Objectives: To determine which of two methods of case note review – holistic (implicit) and criterion-based (explicit) – provides the most useful and reliable information for quality and safety of care, and the level of agreement within and between groups of health-care professionals when they use the two methods to review the same record. To explore the process–outcome relationship between holistic and criterion-based quality-of-care measures and hospital-level outcome indicators. © 2010 Crown Copyrigh

Phenomenological glass model for vibratory granular compaction

A model for weakly excited granular media is derived by combining the free volume argument of Nowak et al. [Phys. Rev. E 57, 1971 (1998)] and the phenomenological model for supercooled liquids of Adam and Gibbs [J. Chem. Phys. 43, 139 (1965)]. This is made possible by relating the granular excitation parameter \Gamma, defined as the peak acceleration of the driving pulse scaled by gravity, to a temperature-like parameter \eta(\Gamma). The resulting master equation is formally identical to that of Bouchaud's trap model for glasses [J. Phys. I 2, 1705 (1992)]. Analytic and simulation results are shown to compare favourably with a range of known experimental behaviour. This includes the logarithmic densification and power spectrum of fluctuations under constant \eta, the annealing curve when \eta is varied cyclically in time, and memory effects observed for a discontinuous shift in \eta. Finally, we discuss the physical interpretation of the model parameters and suggest further experiments for this class of systems.Comment: 2 references added; some figure labels tweaked. To appear in PR

Reach of the Fermilab Tevatron for minimal supergravity in the region of large scalar masses

The reach of the Fermilab Tevatron for supersymmetric matter has been calculated in the framework of the minimal supergravity model in the clean trilepton channel. Previous analyses of this channel were restricted to scalar masses m_0<= 1 TeV. We extend the analysis to large values of scalar masses m_0\sim 3.5 TeV. This includes the compelling hyperbolic branch/focus point (HB/FP) region, where the superpotential \mu parameter becomes small. In this region, assuming a 5\sigma (3\sigma) signal with 10 (25) fb^{-1} of integrated luminosity, the Tevatron reach in the trilepton channel extends up to m_{1/2}\sim 190 (270) GeV independent of \tan\beta . This corresponds to a reach in terms of the gluino mass of m_{\tg}\sim 575 (750) GeV.Comment: 11 page latex file including 6 EPS figures; several typos corrected and references adde

Enhancement of Commercial Antifungal Agents by Kojic Acid.

publishersversionpublishe

Partial-wave analysis of the eta pi+ pi- system produced in the reaction pi-p --> eta pi+ pi- n at 18 GeV/c

A partial-wave analysis of 9082 eta pi+ pi- n events produced in the reaction pi- p --> eta pi+ pi- n at 18.3 GeV/c has been carried out using data from experiment 852 at Brookhaven National Laboratory. The data are dominated by J^{PC} = 0^{-+} partial waves consistent with observation of the eta(1295) and the eta(1440). The mass and width of the eta(1295) were determined to be 1282 +- 5 MeV and 66 +- 13 Mev respectively while the eta(1440) was observed with a mass of 1404 +- 6 MeV and width of 80 +- 21 MeV. Other partial waves of importance include the 1++ and the 1+- waves. Results of the partial wave analysis are combined with results of other experiments to estimate f1(1285) branching fractions. These values are considerably different from current values determined without the aid of amplitude analyses.Comment: 22 pages, 8 figure