Integration-free interval doubling for Riccati equation solutions

Various algorithms are given for the case of constant coefficients. The algorithms are based on two ideas: first, relate the Re solution with general initial conditions to anchored RE solutions; and second, when the coefficients are constant the anchored solutions have a basic shift-invariance property. These ideas are used to construct an integration free superlinearly convergent iterative solution to the algebraic RE. The algorithm, arranged in square-root form, is thought to be numerically stable and competitive with other methods of solving the algebraic RE

Atomistic study of electronic structure of PbSe nanowires

Lead Selenide (PbSe) is an attractive `IV-VI' semiconductor material to design optical sensors, lasers and thermoelectric devices. Improved fabrication of PbSe nanowires (NWs) enables the utilization of low dimensional quantum effects. The effect of cross-section size (W) and channel orientation on the bandstructure of PbSe NWs is studied using an 18 band $sp^3d^5$ tight-binding theory. The bandgap increases almost with the inverse of the W for all the orientations indicating a weak symmetry dependence. [111] and [110] NWs show higher ballistic conductance for the conduction and valence band compared to [100] NWs due to the significant splitting of the projected L-valleys in [100] NWs.Comment: 4 figures, Prepared for AP

Effect of Feed Delivery Management on Yearling Steer Performance

Gain efficiency by cattle fed high grain diets can be affected by feed delivery management (FDM). Restricted or limit feeding improves feed efficiency but can reduce ADG. This experiment was designed to evaluate if feeding near ad libitum intake while reducing the amount of variation between daily feed deliveries could provide feed efficiency advantages over unrestricted access to feed without restricting ADG. The FDM strategies for the 121-day feeding period included prescription intakes (PI) where variability between day to day feed deliveries were minimized or ad libitum intake (ALI) where feed was always available. Crossbred yearling steers (n = 76, initial BW 866 Ib ± 6.72) of mixed origin were stratified by BW and randomly assigned to one of two treatments then to one of five pens within a treatment. The 92% concentrate, 63 Mcal NE,/cwt diet, was fed to the PI group throughout the 121 –day study. Four step-up diets were fed over 12 days to adapt the ALI group to the 92% concentrate diet. Feed was delivered daily at 0730 and 1630. The bunks were slick for the PI treatment at 0700 69% of the days on feed and 40% for the ALI treatment (P\u3c .01). The PI fed steers consumed less DM (P\u3c .001) during interim periods days 1 to 29 and 58 to 85 (P\u3c.05). The PI steers were more efficient days 1 to 29 (P\u3c .03) and overall (P\u3c.10). Carcass variables associated with yield grade were not affected (P\u3e.10) by FDM and PI caused higher marbling scores (5.67 vs 5.31; P\u3c .085), while percent choice did not differ, 74 vs 79% for the PI and ALI treatments, respectively. The PI treatment lowered (P\u3c .05) feed cost $5.30/cwt gain. This experiment indicated that FDM can influence DM1 and feed efficiency without compromising ADG

Evaluation of Pt, Ni, and Ni–Mo electrocatalysts for hydrogen evolution on crystalline Si electrodes

The dark electrocatalytic and light photocathodic hydrogen evolution properties of Ni, Ni–Mo alloys, and Pt on Si electrodes have been measured, to assess the viability of earth-abundant electrocatalysts for integrated, semiconductor coupled fuel formation. In the dark, the activities of these catalysts deposited on degenerately doped p^+-Si electrodes increased in the order Ni < Ni–Mo ≤ Pt. Ni–Mo deposited on degenerately doped Si microwires exhibited activity that was very similar to that of Pt deposited by metal evaporation on planar Si electrodes. Under 100 mW cm^(−2) of Air Mass 1.5 solar simulation, the energy conversion efficiencies of p-type Si/catalyst photoelectrodes ranged from 0.2–1%, and increased in the order Ni ≈ Ni–Mo < Pt, due to somewhat lower photovoltages and photocurrents for p-Si/Ni–Mo relative to p-Si/Ni and p-Si/Pt photoelectrodes. Deposition of the catalysts onto microwire arrays resulted in higher apparent catalytic activities and similar photoelectrode efficiencies than were observed on planar p-Si photocathodes, despite lower light absorption by p-Si in the microwire structures

Dialectica Categories for the Lambek Calculus

We revisit the old work of de Paiva on the models of the Lambek Calculus in dialectica models making sure that the syntactic details that were sketchy on the first version got completed and verified. We extend the Lambek Calculus with a \kappa modality, inspired by Yetter's work, which makes the calculus commutative. Then we add the of-course modality !, as Girard did, to re-introduce weakening and contraction for all formulas and get back the full power of intuitionistic and classical logic. We also present the categorical semantics, proved sound and complete. Finally we show the traditional properties of type systems, like subject reduction, the Church-Rosser theorem and normalization for the calculi of extended modalities, which we did not have before

A Millimeter-wave Galactic Plane Survey with the BICEP Polarimeter

In order to study inflationary cosmology and the Milky Way Galaxy's composition and magnetic field structure, Stokes I, Q, and U maps of the Galactic plane covering the Galactic longitude range 260° < ℓ < 340° in three atmospheric transmission windows centered on 100, 150, and 220 GHz are presented. The maps sample an optical depth 1 ≾ AV ≾ 30, and are consistent with previous characterizations of the Galactic millimeter-wave frequency spectrum and the large-scale magnetic field structure permeating the interstellar medium. The polarization angles in all three bands are generally perpendicular to those measured by starlight polarimetry as expected and show changes in the structure of the Galactic magnetic field on the scale of 60°. The frequency spectrum of degree-scale Galactic emission is plotted between 23 and 220 GHz (including WMAP data) and is fit to a two-component (synchrotron and dust) model showing that the higher frequency BICEP data are necessary to tightly constrain the amplitude and spectral index of Galactic dust. Polarized emission is detected over the entire region within two degrees of the Galactic plane, indicating the large-scale magnetic field is oriented parallel to the plane of the Galaxy. A trend of decreasing polarization fraction with increasing total intensity is observed, ruling out the simplest model of a constant Galactic magnetic field orientation along the line of sight in the Galactic plane. A generally increasing trend of polarization fraction with electromagnetic frequency is found, varying from 0.5%-1.5% at frequencies below 50 GHz to 2.5%-3.5% above 90 GHz. The effort to extend the capabilities of BICEP by installing 220 GHz band hardware is described along with analysis of the new band

Enhanced Stability and Efficiency for Photoelectrochemical Iodide Oxidation by Methyl Termination and Electrochemical Pt Deposition of n-Si Microwire Arrays

Arrays of Si microwires doped n-type (n-Si) and surface-functionalized with methyl groups have been used, with or without deposition of Pt electrocatalysts, to photoelectrochemically oxidize I–(aq) to I_3–(aq) in 7.6 M HI(aq). Under conditions of iodide oxidation, methyl-terminated n-Si microwire arrays exhibited stable short-circuit photocurrents over a time scale of days, albeit with low energy-conversion efficiencies. In contrast, electrochemical deposition of Pt onto methyl-terminated n-Si microwire arrays consistently yielded energy-conversion efficiencies of ∼2% for iodide oxidation, with an open-circuit photovoltage of ∼400 mV and a short-circuit photocurrent density of ∼10 mA cm^(–2) under 100 mW cm^(–2) of simulated air mass 1.5G solar illumination. Platinized electrodes were stable for >200 h of continuous operation, with no discernible loss of Si or Pt. Pt deposited using electron-beam evaporation also resulted in stable photoanodic operation of the methyl-terminated n-Si microwire arrays but yielded substantially lower photovoltages than when Pt was deposited electrochemically

Influence of Dietary MP on the Production Rates and N Usage by Steers Fed High Grain Content Diets

An experiment was conducted to determine if dietary metabolizable protein (MP) could be manipulated to reduce N content of feedlot effluent without compromising production rates in yearling steers fed high grain content diets. Three feeding programs included: LO) 11 % CP fed throughout; HI) 13% CP fed throughout; and LHL) 11 % fed from d 1 to 35, 13% CP (HI) fed d 36 to 94 and 1 1 % CP (LO) fed from d 95 to 1 17. An estradiol-trenbalone acetate implant was administered on d 35. There were 5 pens of 8 steers (BW=7561b) assigned to each treatment. The MP allowed ADG for the diets were 3.3 and 4.0 Ib for the LO and HI diets respectively. Cumulative ADG and feed efficiency were improved (Pc.05) by feeding the HI diet. Fluctuations in interim growth rates obscured the determination of specifically when this effect occurred. The faster growth rate was associated with heavier and fatter carcasses. An evaluation of serum urea-N concentrations suggested that the influence of the growth promotant on N metabolism was beginning to diminish within 56d. The HI diet caused higher (P\u3c .05) serum urea-N levels at 63, 91 and 117d on feed. Total N intake was calculated by pen and increased (P\u3c .01) from 41.4 to 47.3 to 51.2 Ib/steer for treatments LO, LHL and HI respectively. The N intake1100 BW gained increased (P\u3c .01) from 9.89 to 10.90 to 11.33 Ib for LO, LHL and HI treatments respectively. These results indicate that increasing production efficiency by elevating the MP content of diets may not cause a concomitant improvement in the efficiency of N retention on the feedlot scale

Estimating Parameterized Post-Newtonian Parameters from Spacecraft Radiometric Tracking Data

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77381/1/AIAA-7647-407.pd

Fusion versus Breakup: Observation of Large Fusion Suppression for ^9Be + ^{208}Pb

Complete fusion excitation functions for $^{9}$Be + $^{208}$Pb have been measured to high precision at near barrier energies. The experimental fusion barrier distribution extracted from these data allows reliable prediction of the expected complete fusion cross-sections. However, the measured cross-sections are only 68% of those predicted. The large cross-sections observed for incomplete fusion products support the interpretation that this suppression of fusion is caused by $^{9}$Be breaking up into charged fragments before reaching the fusion barrier. Implications for the fusion of radioactive nuclei are discussed.Comment: RevTex, 11 pages, 2 postscript figures, to appear in PR