Novel waveguide configuration for convenient and sensitive fluorescence and Raman measurements of liquids over optical fibers

Fluorescence has been measured from a waveguide formed by a PTFE tube with an internal coating of a low-refractive-index amorphous fluoropolymer. The configuration is suited to taking measurements from liquids having a refractive index down to 1.32, including, in particular, aqueous solutions. The parameters which determine the optical collection efficiency have been mathematically modelled. We have produced waveguides up to 1m long, and with 0.955 mm and 0.445 mm internal radii, and measured a (fluorescence) collection enhancement factor of 3 from a 140 mm long, 0.955 mm internal radius waveguide. Work is continuing to increase the enhancement factor

Vickrey Auctions for Irregular Distributions

The classic result of Bulow and Klemperer \cite{BK96} says that in a single-item auction recruiting one more bidder and running the Vickrey auction achieves a higher revenue than the optimal auction's revenue on the original set of bidders, when values are drawn i.i.d. from a regular distribution. We give a version of Bulow and Klemperer's result in settings where bidders' values are drawn from non-i.i.d. irregular distributions. We do this by modeling irregular distributions as some convex combination of regular distributions. The regular distributions that constitute the irregular distribution correspond to different population groups in the bidder population. Drawing a bidder from this collection of population groups is equivalent to drawing from some convex combination of these regular distributions. We show that recruiting one extra bidder from each underlying population group and running the Vickrey auction gives at least half of the optimal auction's revenue on the original set of bidders

Metallurgical bonding development of V–4Cr–4Ti alloy for the DIII-D radiative divertor program

General Atomics (GA), in conjunction with the Department of Energy`s (DOE) DIII-D Program, is carrying out a plan to utilize a vanadium alloy in the DIII-D tokamak as part of the DIII-D Radiative Divertor (RD) upgrade. The V-4Cr-4Ti alloy has been selected in the U.S. as the leading candidate vanadium alloy for fusion applications. This alloy will be used for the divertor fabrication. Manufacturing development with the V-4Cr-4Ti alloy is a focus of the DIII-D RD Program. The RD structure, part of which will be fabricated from V-4Cr-4Ti alloy, will require many product forms and types of metal/metal bonded joints. Metallurgical bonding methods development on this vanadium alloy is therefore a key area of study by GA. Several solid state (non-fusion weld) and fusion weld joining methods are being investigated. To date, GA has been successful in producing ductile, high strength, vacuum leak tight joints by all of the methods under investigation. The solid state joining was accomplished in air, i.e., without the need for a vacuum or inert gas environment to prevent interstitial impurity contamination of the V-4Cr-4Ti alloy

Flowing with Eight Supersymmetries in M-Theory and F-theory

We consider holographic RG flow solutions with eight supersymmetries and study the geometry transverse to the brane. For both M2-branes and for D3-branes in F-theory this leads to an eight-manifold with only a four-form flux. In both settings there is a natural four-dimensional hyper-Kahler slice that appears on the Coulomb branch. In the IIB theory this hyper-Kahler manifold encodes the Seiberg-Witten coupling over the Coulomb branch of a U(1) probe theory. We focus primarily upon a new flow solution in M-theory. This solution is first obtained using gauged supergravity and then lifted to eleven dimensions. In this new solution, the brane probes have an Eguchi-Hanson moduli space with the M2-branes spread over the non-trivial 2-sphere. It is also shown that the new solution is valid for a class of orbifold theories. We discuss how the hyper-Kahler structure on the slice extends to some form of G-structure in the eight-manifold, and describe how this can be computed.Comment: 29 pages, 1 figure, harvma

Waterfowl Kill by Cree Hunters of the Hudson Bay Lowland, Ontario

From 1974 to 1976 annual interviews were conducted with 97% of male Indian potential hunters at James Bay and Hudson Bay coastal villages to determine waterfowl kill. Sample interviews were conducted at inland villages. Of those interviewed at coastal communities, 87% hunted waterfowl. The mean yearly take of all species ranged from 55 to 145 birds per hunter. Lesser Snow Geese and large Canada Geese were the main prey, averaging 38,350 and 23,152 birds shot per year, respectively. Small numbers of other goose species were taken. The duck kill averaged 22,715. Eighty percent of the large Canada Goose kill occurred in spring; 76% of Snow Geese were taken in fall. Considerable inter-year variation in total kill occurred. The take for the highest kill year (1975-76) exceeded that for the lowest (1976-77) by 61% for Snow Geese and 34% for large Canada Geese; the spring kill was particularly variable. The kill of Snow Geese has apparently increased by a factor of 2, and that of large Canada Geese by a factor of 3, since the mid-1950s. Through analysis of band recoveries, the kill was determined to have been apportioned among separately managed stocks. The Indian kill made up approximately 13% of the total hunting kill of the Tennessee Valley Population, 9% of the Mississippi Valley Population, and 7% of Hudson Bay Lesser Snow Geese.Key words: Indian wildlife kill, waterfowl harvest, Hudson Bay Lowland, CreeDe 1974 à 1976, nous avons interviewé chaque année 97% des chasseurs indiens males possibles dans les villages côtiers de la baie d'Hudson et de la baie James, en Ontario, ainsi que dans villages intérieurs servant d'échantillons, afin de déterminer le nombre d'oiseaux marins tués. Quatre-vingt-sept pour cent des hommes interviewés dans les communautés côtières faisaient la chasse aux oiseaux marins. Le nombre annuel moyen de proies comptant toutes les espèces variait entre 55 et 145 oiseaux par chasseur dans divers villages. Les oies blanches de taille inférieure et les bernaches canadiennes de grosse taille étaient les proies principales, moyennant 38 350 et 23 152 oiseaux tirés par année, respectivement. D'autres espèces d'oies étaient prises en petites quantités. Une moyenne de 22 715 canards furent aussi tués. Quatre-vingt pour cent de la prise de grosses bernaches canadiennes s'effectuait au printemps et 76% des oies blanches étaient tuées en automne. Le nombre total d'oiseaux tués variait de façon considérable d'année. Le plus haut pourcentage (1975-76) excédait le pourcentage le moins élevé (1976-77) de 61% pour l'oie blanche et de 34% pour les grosses bernaches, les variations printanières étant particulièrement marquées. Les prises d'oies blanches semblent avoir doublé, et celles de bernaches semblent avoir triplé, depuis le milieu des années '50. Au moyen de l'analyse du retour de bagues, les prises ont été réparties parmi des groupes séparément contrôlés. Les prises indiennes formaient environ 13% de la chasse totale de la population de la vallée du Tennessee, 9% de la population de la vallée du Mississippi, et 7% des oies blanches de taille inférieure dans la baie d'Hudson.Mots clés: prises de chasse d'animaux sauvages par les Indiens, prises de chasse parmi les oiseaux marins, terres basses de la baie d'Hudso

Effect of implant strategy and Optaflexx administration on feedlot performance and skeletal muscle β-adrenergic receptor and insulin-like growth factor I mRNA abundance

Feedlot heifers (1,147) weighing 622 lb were used to evaluate the effects of implant strategy and Optaflexx administration. Implant treatments included Revalor-200 (R200) at arrival, or Revalor-IH at arrival and reimplantation with Finaplix-H on day 58 (RF). Optaflexx (200 mg/heifer daily of ractopamine-HCl) was fed the last 28 days. Treatments were randomly assigned to 16 pens. After 182 days, heifers were slaughtered, at which time carcass data were obtained and semimembranosus muscle tissue was excised for RNA isolation. Optaflexx administration significantly increased average daily gain (0.7 lb/day), feed efficiency (3%), hot carcass weight (10.5 lb), and ribeye area (0.42 square inches); decreased back fat thickness; and improved yield grade. There was no significant treatment effect on the expression of β1-adrenergic receptor (AR) mRNA, but there was a tendency for Optaflexx feeding to increase β2-AR mRNA concentrations. For β3-AR mRNA, Optaflexx treatment numerically increased β3-AR mRNA in heifers implanted with R200, but significantly decreased expression in heifers implanted with RF. Optaflexx also significantly decreased IGF-I mRNA in heifers implanted with RF, but numerically increased IGF-I mRNA in heifers implanted with R200. This data aids our understanding of the interaction between steroidal implants and Optaflexx in feedlot heifers. Knowledge about the modes of action of various growth promotants will aid in designing growth promotion strategies to enhance the efficiency of lean tissue deposition in feedlot cattle

Gravity duals to deformed SYM theories and Generalized Complex Geometry

We analyze the supersymmetry conditions for a class of SU(2) structure backgrounds of Type IIB supergravity, corresponding to a specific ansatz for the supersymmetry parameters. These backgrounds are relevant for the AdS/CFT correspondence since they are suitable to describe mass deformations or beta-deformations of four-dimensional superconformal gauge theories. Using Generalized Complex Geometry we show that these geometries are characterized by a closed nowhere-vanishing vector field and a modified fundamental form which is also closed. The vector field encodes the information about the superpotential and the type of deformation - mass or beta respectively. We also show that the Pilch-Warner solution dual to a mass-deformation of N =4 Super Yang-Mills and the Lunin-Maldacena beta-deformation of the same background fall in our class of solutions.Comment: LaTex, 29 page

Effect of Optaflexx and days on feed on feedlot performance, carcass characteristics, and skeletal muscle gene expression in yearling steers

Two-thousand two-hundred fifty-two yearling steers (690 lb) were used to evaluate the effects of Optaflexx and days on feed on finishing steer performance and carcass characteristics. Treatment groups included serial harvest dates of 150, 171, or 192 days. Within each harvest date, steers either received Optaflexx (200 mg/steer daily of ractopamine-HCl) for the final 28 days, or did not receive Optaflexx. All steers were initially implanted with Revalor-IS and were re-implanted with Revalor-S after 75 days on feed. At harvest, muscle samples from the inside round were obtained for mRNA analysis of the β- adrenergic receptors (AR). Optaflexx increased daily gains, hot carcass weight, and ribeye area, and improved feed efficiency. Optaflexx did not affect dressing percentage, USDA yield grade, or quality grade. Optaflexx did not change overall feed intake across the entire feeding period, but feed intake was increased during the 28-day period that steers received Optaflexx. As expected, greater days on feed decreased daily gains, overall feed intake, and the number of yield grade 1 and 2 carcasses, and worsened feed efficiency. Also, greater days on feed increased hot carcass weight, dressing percentage, and the number of prime and choice carcasses, as well as the number of yield grade 4 and 5 carcasses. Increasing days on feed decreased the abundance of mRNA for β1-AR and β3-AR, and increased the abundance of β2-AR mRNA. Optaflexx had no effect on abundance of mRNA for β1-AR or β3-AR, but it increased the abundance of mRNA for β2-AR. Optaflexx may affect expression of the β2-AR gene in skeletal muscle, which could impact the performance responses to Optaflexx feeding in steers

Third-order relativistic many-body calculations of energies and lifetimes of levels along the silver isoelectronic sequence

Energies of 5l_j (l= s, p, d, f, g) and 4f_j states in neutral Ag and Ag-like ions with nuclear charges Z = 48 - 100 are calculated using relativistic many-body perturbation theory. Reduced matrix elements, oscillator strengths, transition rates and lifetimes are calculated for the 17 possible 5l_j-5l'_{j'} and 4f_j-5l_{j'} electric-dipole transitions. Third-order corrections to energies and dipole matrix elements are included for neutral Ag and for ions with Z60. Comparisons are made with available experimental data for transition energies and lifetimes. Correlation energies and transition rates are shown graphically as functions of nuclear charge Z for selected cases. These calculations provide a theoretical benchmark for comparison with experiment and theory.Comment: 8 page