cssi/SciSciGPT-SciSciNet huggingface dataset:
Non-Commutative Harmonic and Subharmonic Polynomials

The paper introduces a notion of the Laplace operator of a polynomial p in noncommutative variables x = (x1,…, xg). The Laplacian Lap[p, h] of p is a polynomial in x and in a noncommuting variable h. When all variables commute we have Lap[p, h] = h2Δxp where Δxp is the usual Laplacian. A symmetric polynomial in symmetric variables will be called harmonic if Lap[p, h] = 0 and subharmonic if the polynomial q(x, h) := Lap[p, h] takes positive semidefinite matrix values whenever matrices X1,…, Xg, H are substituted for the variables x1,…, xg, h. In this paper we classify all homogeneous symmetric harmonic and subharmonic polynomials in two symmetric variables. We find there are not many of them: for example, the span of all such subharmonics of any degree higher than 4 has dimension 2 (if odd degree) and 3 (if even degree). Hopefully, the approach here will suggest ways of defining and analyzing other partial differential equations and inequalities.
The Interaction of Implicit and Explicit Contracts in Repeated Agency

Abstract In a repeated principal–agent model in which the agent's actions are observable to the principal but not verifiable in court, the agent's incentives derive both from salary payments based on verifiable signals and from implicit promises by the principal of bonuses for good behavior. Explicit short-term contracts are designed to enhance the effectiveness of the infinite-horizon implicit contract between principal and agent. In a constrained-efficient equilibrium, bonuses smooth the consumption path of the risk-averse agent by moving in the opposite direction from salaries, total consumption, and expected discounted utility for the rest of the game. Journal of Economic Literature Classification Numbers: C7, C73, D8.
Surface-Curvature-Distribution Effects on Turbine-Cascade Performance

The manufacturing accuracy of turbine blades is judged by the difference between the designed and produced location of each point around the airfoils. This paper shows that the design-point and off-design-point aerodynamic and heat transfer performance of turbine cascades is affected siggnificantly by the distribution of curvature along the suction and pressure surfaces, and less significantly by the exact location of each one point. The performances of turbine blades designed with continuous slope of curvature distribution, and with slight discontinuities in the slope of curvature, are examined using a computer program for various design and off-design flow conditions. The accuracy of the computations is checked by comparison of computational results with cascade solutions of known experimental output
Phase relations in chromium oxide-containing systems at elevated temperatures

Abstract The role of chromium in oxide and silicate systems is examined by reviewing typical features of phase diagrams involving this component. Liquidus, solidus and sub-solidus phase relations are discussed for a number of binary, ternary, quaternary and multicomponent systems having a bearing on the behavior of chromium in minerals and rocks. The most dominant features of the liquidus surface of Cr 2 O 3 -containing silicate systems are the large liquid miscibility gaps and the dominance of the spinel (chromite) stability field. Subsolidus relations of especial interest are those involving spinel phases (chromites). The oxygen pressure of the gas phase is an important parameter in chromium oxide-containing systems, partly because iron oxide is a common constituent of such systems, partly because chromium itself may occur in different states of oxidation. At the lowest oxygen pressures considered, a significant proportion of the chromium may be present as Cr 2+ , and at the highest oxygen pressures as Cr 6+ .
Quantum Algebra of the Particle Moving on the q-Deformed Mass-Hyperboloid

I introduce a reality structure on the Heisenberg double of Funq(SL(N,C)) for q phase, which for N=2 can be interpreted as the quantum phase space of the particle on the q-deformed mass-hyperboloid. This construction is closely related to the q-deformation of the symmetric top. Finally, I conjecture that the above real form describes zero modes of certain noncompact WZNZ-models.
Nebular condensation of moderately volatile elements and their abundances in ordinary chondrites

Two models accounting for the concentrations of moderately volatile elements in ordinary chondrites are discussed. The first relies on an apparent correlation between ordinary chondrite/type-I carbonaceous chondrite abundance ratios and ideal solution-condensation temperatures of such elements as Sn, Cu, Li, Na, and Mn to construct a model in which volatiles are lost as gases before nebular condensation or as finely-divided solids that are incompletely agglomerated, and the condensation/agglomeration efficiency declines as a function of time. The second theory largely discounts this gas-dust diffraction effect and instead proposed condensation on matrix and volatization from chondules and coarse metal grains as mechanisms explaining the apparent existence of three distinct classes of volatile-element abundance in ordinary chondrites.
Nucleophilic displacements of N‐aryl and heteroaryl groups. Part 8 . Intermolecular reactions of N‐aryl‐pyridinium, ‐quinolinium, and ‐acridinium salts with nucleophiles

N-Aryl-mono-, -tri- and -pentacyclic pyridinium cations react with S- and C-nucleophiles to give: (i) simple addition of hydride at the α-ring position, (ii) nucleophilic addition of thiophenoxide at the γ-ring position, (iii) deprotonation at the 6-position of a 5,6-dihydroquinolinium ring followed by prototropic shift to give a 1,2-dihydroquinoline derivative, (iv) ring contraction of a pyridine to a pyrrole ring, and (v) nucleophilic displacement of the N-aryl group.
The equivariant slice filtration: a primer

We present an introduction to the equivariant slice filtration. After reviewing the definitions and basic properties, we determine the slice-connectivity of various families of naturally arising spectra. This leads to an analysis of pullbacks of slices defined on quotient groups, producing new collections of slices. Building on this, we determine the slice tower for the EilenbergMac Lane spectrum associated to a Mackey functor for a cyclic p-group. We then relate the Postnikov tower to the slice tower for various spectra. Finally, we pose a few conjectures about the nature of slices and pullbacks.
Five-branes and M theory on an orbifold

Abstract We relate Type IIB superstrings compactified to six dimensions on K3 to an eleven-dimensional theory compactified on (S1)5/ Z 2. Eleven-dimensional five-branes enter the story in an interesting way.
Structural effects in fluorinated cyclopropanes: A microwave study of cis-1,1,2,3-tetrafluorocyclopropane

Abstract Microwave and RFMDR spectra of cis- CHFCHFC F2, cis-13 CHFCHFC F2, cis- CDFCDFC F2, and cis-13 CDFCDFC F2 have been measured between 26.5 and 40.0 GHz using an HP 8400C spectrometer. The a- and c-type transitions were assigned and fit to the quartic Watson Hamiltonian giving A = 3450.445(2) MHz, B = 2402.831(3) MHz, C = 2060.247(3) MHz, ΔJ = 0.39(3) kHz, ΔJK = 0.26(1) kHz, δK = 1.606(9) kHz, δJ = 0.059(1) kHz, and δJK = −0.58(2) kHz for cis- CHFCHFC F2. A structure is derived from the moment of inertia data by fixing three parameters associated with the CF2 group. The rS parameters for the CHFCHF segment of the molecule in the CHFCHFC F2 isotopic frame are r (C 2 C 3 ) = 1.533(3) A , r (C 2,3 H) = 1.099(3) A , r (F 2 ⋯ F 3 ) = 2.775(2) A , and r (H 2 ⋯ H 3 ) = 2.622(2) A . Two algorithms describing the CC and CF bond distances are fitted to gas phase structural data for a series of fluorinated cyclopropane derivatives. A partial test of these algorithms is obtained from the structure of cis- CHFCHFC F2. The structural results are related to theoretical studies of fluorination effects in cyclopropane derivatives.
Assessing the Massive Young Sun Hypothesis to Solve the Warm Young Earth Puzzle

A moderately massive young Sun has been proposed to resolve the so-called faint young Sun paradox. We calculate the time evolution of the solar mass that would be required by this hypothesis using a simple parameterized energy-balance model for Earth's climate. Our calculations show that the solar mass-loss rate would need to have been 2-3 orders of magnitude higher than at present for a time on the order of ~2 Gyr. Such a mass-loss history is significantly at variance (both in the timescale and in the magnitude of the mass-loss rates) with that inferred from astronomical observations of mass loss in younger solar analogs. While suggestive, the astronomical data cannot completely rule out the possibility that the Sun had the required mass-loss history; therefore, we also examine the effects of the hypothetical historical solar mass loss on orbital dynamics in the solar system, with a view to identifying additional tests of the hypothesis. We find that ratios of planetary orbital spacings remain unchanged, relative locations of planetary mean motion and secular resonances remain unchanged, but resonance widths and the sizes of the Hill spheres of all planets increase as the Sun loses mass. The populations and dynamics of objects near resonances with the planets, as well as those of distant irregular satellites of the giant planets, may contain the signature of a more massive young Sun. Planetary and satellite orbits provide a few tests, but these are weak or non-unique.
A Neutron Star Identification for the High-Energy Gamma-Ray Source 3EG J1835+5918 Detected in the ROSAT All-Sky Survey

In the error box of 3EG J1835+5918, the brightest as-yet unidentified EGRET source at intermediate Galactic latitude, we find a weak, ultrasoft X-ray source at energies E 25.2. The corresponding lower limit on fX/fV is 300, which signifies that the X-ray source is probably a thermally emitting neutron star. Considering our previous complete multiwavelength survey of the 3EG J1835+5918 region, which failed to find any other notable candidate for identification with 3EG J1835+5918, we propose that this X-ray source, RX J1836.2+5925, is a rotation-powered γ-ray pulsar that is either older or more distant than the prototype Geminga. We see marginal evidence for variability between two ROSAT HRI observations. If real, this would indicate that the X-ray emission has an external origin, perhaps due to intermittent heating of the polar caps by a variable particle accelerator. RX J1836.2+5925 could even be an old, recycled pulsar, which may nevertheless have a high γ-ray efficiency.
Template-competitive inhibitors of HIV-1 reverse transcriptase: design, synthesis and inhibitory activity.

We report the design, synthesis and activity studies on a novel class of template-competitive reverse transcriptase inhibitors (TCRTIs). The TCRTIs are 1,N(6)-etheno analogues of a series of dATP-based template-competitive DNA polymerase inhibitors synthesized in our laboratory (Moore, B. M.; Jalluri, R.; Doughty, M.B. Biochemistry 1996, 35, 11634). Thus, nucleotides 2-(4-azidophenacyl)thio-1,N(6)-etheno-2'-deoxyadenosine 5'-triphosphate 1, the tetrafluoro analogue 2-(4-azido-2,3,5,6-tetrafluorophenacyl)thio-1,N(6)-etheno-2'-deoxyadenosine 5'-triphosphate 2 and its analogues were synthesized by alkylation of 2-thio-1,N(6)-etheno-2'-deoxyadenosine 5'-monophosphate with the corresponding chloro- or bromo-alkyl halides and converted to the triphosphate. Kinetically, nucleotides 1 and 2 are both competitive inhibitors of reverse transcriptase versus template/primer with K(i)'s of 8.0 and 7.4 microM, respectively, and non-competitive inhibitors versus TTP with K(i)'s of 15 and 10 microM, respectively. Nucleotide 3, which differs from 1 only in that it lacks the etheno group, non-complementary nucleotide triphosphates, and related monophosphates and nucleosides, are completely inactive as inhibitors of reverse transcriptase at concentrations up to 1 mM. Photoinactivation of RT by 1 was both time- and concentration-dependent, and protected by template/primer but not by dNTPs. The concentration-dependent inactivation data gave a K(D,app) of 17.2 microM and maximum inactivation of 90%, and radiolabeled [beta, gamma-32P]-1 photoincorporated specifically and covalently into the p66 subunit of RT. Thus the photoinactivation data support our main conclusion from the kinetic data that this class of RT inhibitors are non-substrate and template-competitive.
Using LSI processor bit-slices to build a PDP-11: a case study in microcomputer design

In this article we give the design and evaluation of the CMU-11: a fully operational implementation of the PDP-11 computer architecture built with Intel 3000 Schottky bipolar microcomputer bit-slices. This project was initiated to test in detail the claims that LSI processor bit-slices simplify the design of microprogrammed processors. The CMU-11 executes approximately 240,000 instructions per second, which is about 63 percent the speed of the PDP-11/40 and twice the speed of the LSI-11.We explore in some detail the additional logic that was added to enable the Intel 3000 circuits to emulate the PDP-11 instruction set. We specified full DEC Unibus compatibility and 29 percent of the integrated circuits used to implement the CMU-11 were required to provide buffering and control of the Unibus. The other main sources of inefficiency were the lack of arithmetic overflow logic in the bit-slices and the organization of the microinstruction control store. We show how improved LSI circuits in this area can substantially reduce the size (and cost) of the processor.The set of design aids currently available at Carnegie-Mellon University was of critical assistance in this project and we include a critique of our use of these design aids to show their utility in prototype design efforts.
Enthalpies of hydrogenation of the n-heptenes and the methylhexenes

Abstract The enthalpies of hydrogenation are given for all isomers of n-heptene and of the methylhexenes, for which there are few literature values.
Curvature-based signatures for object description and recognition

An invariant related to Gaussian curvature at an object point is developed based upon the covariance matrix of photometric values within a local neighborhood about the point. We employ three illumination conditions, two of which are completely unknown. We never need to explicitly know the surface normal at a point. The determinant of the covariance matrix of the intensity three-tuples in the local neighborhood of an object point is shown to be invariant with respect to rotation and translation. A way of combing these determinant to form a signature distribution is formulated that is rotation, translation, and scale invariant. This signature is shown to be invariant over large ranges of poses of the same objects, while being significantly different between distinctly shaped objects. A new object recognition methodology is proposed by compiling signatures for only a few viewpoints of a given object.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Improved procedures for the palladium-catalyzed intermolecular arylation of cyclic alkenes

Abstract Improved procedures for the palladium-catalyzed, intermolecular, allylic cross-coupling of aryl halides and cyclic alkenes inhibit double-bond isomerization and accommodate many important functional groups.
Gap-Definability as a Closure Property

Gap-definability and the gap closure operator were defined by S. Fenner, L. Fortnow and S. Kurth (J. Comput. System Sci.48, 116?148 (1994)). Few complexity classes were known at that time to be gap-definable. In this paper, we give simple characterizations of both gap-definability and the gap-closure operator, and we show that many complexity classes are gap-definable, includingP#P,P#P1],PSPACE,EXP,NEXP,MP(Middle-bitP), andBP·?P. If a class is closed under union and intersection and contains ? and?*, then it is gap-definable if and only if it containsSPP; its gap-closure is the closure of this class together withSPPunder union and intersection. On the other hand, we give some examples of classes which are reasonable and gap-definable but not closed under union (resp. intersection, complement). Finally, we show that a complexity class such asPSPACEorPP, if it is not equal toSPP, contains a maximal gap-definable many?one reduction-closed subclass, which is properly betweenSPPand the class of allPSPACE-incomplete (PP-incomplete) sets with respect to containment. The gap-closure of the class of all incomplete sets inPSPACE(resp.PP) isPSPACE(resp.PP).
Cascades: scalable, flexible and composable middleware for multi-modal sensor networking applications

This paper describes the design and implementation of Cascades, a scalable, flexible and composable middleware platform for multi-modal sensor networking applications. The middleware is designed to provide a way for application writers to use pre-packaged routines as well as incorporate their own application-tailored code when necessary. As sensor systems become more diverse in both hardware and sensing modalities, such systems support will become critical. Furthermore, the systems software must not only be flexible, but also be efficient and provide high performance. Experimentation in this paper compares and contrasts several possible implementations based upon testbed measurements on embedded devices. Our experimentation shows that such a system can indeed be constructed.
Adaptive computations of flow around a delta wing with vortex breakdown

An adaptive unstructured mesh solution method for the three-dimensional Euler equations was used to simulate the flow around a sharp edged delta wing. Emphasis was on the breakdown of the leading edge vortex at high angle of attack. Large values of entropy, which indicate vortical regions of the flow, specified the region in which adaptation was performed. The aerodynamic normal force coefficients show excellent agreement with wind tunnel data measured by Jarrah, and demonstrate the importance of adaptation in obtaining an accurate solution. The pitching moment coefficient and the location of vortex breakdown are compared with experimental data measured by Hummel and Srinivasan, showing good agreement in cases in which vortex breakdown is located over the wing.
Prospects for Acceleration of Deuterons and Helions

In order to study the spin structure of the neutron at high energy, a beam rich in polarized neutrons needs to be developed. The neutron has no charge and cannot be accelerated, so either deuterons or helions must be considered. When it comes to spin manipulation and stability of the polarization in a circular accelerator, it is the anomalous part of the magnetic moment which is important. If the anomaly is too small, then manipulation becomes difficult as in the case of deuterons—spin rotators and Siberian snakes become ineffective. 3He nuclei appear to be the easiest choice for a polarized neutron beam. In this paper I discuss the prospects for both helions and deuterons as polarized beams in RHIC or in an electron‐ion collider.
Absolute stability with a generalized sector condition

This paper generalizes the linear sector in the classical absolute stability theory to a sector bounded by concave/convex functions. This generalization allows more flexible or more specific description of the nonlinearity and will thus reduce the conservatism in the estimation of the domain of attraction. We introduce the notions of generalized sector and absolute contractive invariance for estimating the domain of attraction of the origin. Necessary and sufficient conditions are identified under which an ellipsoid is absolutely contractively invariant. In the case that the sector is bounded by piecewise linear concave/convex functions, these conditions can be exactly stated as linear matrix inequalities. Moreover, if we have a set of absolutely contractively invariant (ACI) ellipsoids, then their convex hull is also ACI and inside the domain of attraction. We also present optimization technique to maximize the absolutely contractively invariant ellipsoids for the purpose of estimating the domain of attraction. The effectiveness of the proposed method is illustrated with examples.
Prediction of workpiece surface roughness using soft computing

A study is presented to model surface roughness in end-milling using soft computing (SC) or computational intelligence (CI) techniques. The techniques include the artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS). ANFIS combines the learning capability of ANN and the effective handling of imprecise information in fuzzy logic. Prediction models based on multivariate regression analysis (MRA) are also presented for comparison. The machining parameters, namely, the spindle speed, feed rate, and depth of cut, were used as inputs to model the workpiece surface roughness. The model parameters were tuned using the training data maximizing the modelling accuracy. The trained models were tested using the set of validation data. The effects of different machining parameters, number, and type of model parameters on the prediction accuracy were studied. The procedure is illustrated using the experimental data of end-milling 6061 aluminium alloy. Although statistically all three models predicted roughness with satisfactory goodness of fit, the test performance of ANFIS was better than ANN and MRA. In comparison with MRA, the performance of ANN was better in training but similar in test. The results show the effectiveness of CI techniques in modelling surface roughness.
Asset Prices Under Habit Formation and Reference-Dependent Preferences

This article explains the high level and the countercyclical variation of the equity premium in a consumption-based asset pricing model with low large-scale risk aversion. Investors have gain-loss utility over consumption relative to slowly time-varying habit. Stocks deliver low returns in recessions when consumption falls below habit; investors therefore require a high premium for holding stocks. The model's conditional moment restrictions are tested on consumption and asset returns data. The empirical estimate of large-scale risk aversion is low, whereas the estimate of loss aversion agrees with prior experimental evidence.
Optically and elastically assembled plasmonic nanoantennae for spatially resolved characterization of chemical composition in soft matter systems using surface enhanced spontaneous and stimulated Raman scattering

We present a method to locally probe spatially varying chemical composition of soft matter systems by use of optically controlled and elastically self-assembled plasmonic nanoantennae. Disc-shaped metal particles with sharp irregular edges are optically trapped, manipulated, and assembled into small clusters to provide a strong enhancement of the Raman scattering signal coming from the sample regions around and in-between these particles. As the particles are reassembled and spatially translated by computer-controlled laser tweezers, we probe chemical composition as a function of spatial coordinates. This allows us to reliably detect tiny quantities of organic molecules, such as capping ligands present on various nanoparticles, as well as to probe chemical composition of the interior of liquid crystal defect cores that can be filled with, for example, polymer chains. The strong electromagnetic field enhancement of optically manipulated nanoparticles' rough surfaces is demonstrated in different forms of spectroscopy and microscopy, including enhanced spontaneous Raman scattering, coherent anti-Stokes Raman scattering, and stimulated Raman scattering imaging modes.
Upper-Ocean Processes under the Stratus Cloud Deck in the Southeast Pacific Ocean

Abstract The annual mean heat budget of the upper ocean beneath the stratocumulus/stratus cloud deck in the southeast Pacific is estimated using Simple Ocean Data Assimilation (SODA) and an eddy-resolving Hybrid Coordinate Ocean Model (HYCOM). Both are compared with estimates based on Woods Hole Oceanographic Institution (WHOI) Improved Meteorological (IMET) buoy observations at 20°S, 85°W. Net surface heat fluxes are positive (warming) over most of the area under the stratus cloud deck. Upper-ocean processes responsible for balancing the surface heat flux are examined by estimating each term in the heat equation. In contrast to surface heat fluxes, geostrophic transport in the upper 50 m causes net cooling in most of the stratus cloud deck region. Ekman transport provides net warming north of the IMET site and net cooling south of the IMET site. Although the eddy heat flux divergence term can be comparable to other terms at a particular location, such as the IMET mooring site, it is negligible for the en...
Failure of Aβ(1-40) amyloid fibrils under tensile loading

Amyloid fibrils and plaques are detected in the brain tissue of patients affected by Alzheimer's disease, but have also been found as part of normal physiological processes such as bacterial adhesion. Due to their highly organized structures, amyloid proteins have also been used for the development of nanomaterials, for a variety of applications including biomaterials for tissue engineering, nanolectronics, or optical devices. Past research on amyloid fibrils resulted in advances in identifying their mechanical properties, revealing a remarkable stiffness. However, the failure mechanism under tensile loading has not been elucidated yet, despite its importance for the understanding of key mechanical properties of amyloid fibrils and plaques as well as the growth and aggregation of amyloids into long fibers and plaques. Here we report a molecular level analysis of failure of amyloids under uniaxial tensile loading. Our molecular modeling results demonstrate that amyloid fibrils are extremely stiff with a Young's modulus in the range of 18-30 GPa, in good agreement with previous experimental and computational findings. The most important contribution of our study is our finding that amyloid fibrils fail at relatively small strains of 2.5%-4%, and at stress levels in the range of 1.02 to 0.64 GPa, in good agreement with experimental findings. Notably, we find that the strength properties of amyloid fibrils are extremely length dependent, and that longer amyloid fibrils show drastically smaller failure strains and failure stresses. As a result, longer fibrils in excess of hundreds of nanometers to micrometers have a greatly enhanced propensity towards spontaneous fragmentation and failure. We use a combination of simulation results and simple theoretical models to define critical fibril lengths where distinct failure mechanisms dominate.
Nitrogen-Enriched Quasars in the Sloan Digital Sky Survey First Data Release

The quasar Q0353-383 has long been known to have extremely strong nitrogen intercombination lines at 1486 and 1750 A, implying an anomalously high nitrogen abundance of ~15 times solar. A search for similar nitrogen-rich quasars in the Sloan Digital Sky Survey First Data Release (SDSS DR1) catalog has yielded 20 candidates, including four with nitrogen emission as strong or stronger than that seen in Q0353-383. Our results indicate that only about one in 1700 of quasars have nitrogen abundances similar to Q0353-383, while up to one in 130 may be in the process of extreme nitrogen enrichment.
Aqueous Sonogashira coupling of aryl halides with 1-alkynes under mild conditions: use of surfactants in cross-coupling reactions

Aqueous Sonogashira coupling between lipophilic terminal alkynes and aryl bromides or iodides gave moderate to high yields at 40 °C using readily available and inexpensive surfactants (2.0 w/v% in water) such as SDS and CTAB. The catalyst precursor was 2 mol% Pd(PPh3)2Cl2, and included a 5 mol% Cu(I) co-catalyst for aryl iodide substrates. Aryl-bromide reagents were found to be inhibited by iodide and Cu(I). Studies under Cu(I)-free conditions reveal two competing pathways. A deprotonation pathway gives rise to the traditional Sonogashira product (3), while a carbopalladation pathway produces enyne, 5. The surfactant solution (SDS or CTAB) can be recycled up to three times for coupling between 1-octyne and 1-iodonapthalene in the presence of CuI before the yields decrease.
A 16-Gb/s Backplane Transceiver With 12-Tap Current Integrating DFE and Dynamic Adaptation of Voltage Offset and Timing Drifts in 45-nm SOI CMOS Technology

This paper presents a 16-Gb/s 45-nm SOI CMOS transceiver for multi-standard backplane applications. The receiver uses a 12-tap DFE with circuit refinements for supporting higher data rates. Both the receiver and the transmitter use dynamic adaptation to combat parameter drift due to changing supply voltage and temperature. A 3-tap FFE is included in the source-series-terminated driver. The combination of DFE and FFE permits error-free NRZ signaling at 16 Gb/s over channels exceeding 30 dB loss. The 8-port core with two PLLs is fully characterized for 16 GFC and consumes 385 m W/link.
A Novel Alignment Technique For Pointing And Centering Optical Components

A relatively simple technique was devised to precisely align the components of a diagnostic instrument which recorded the first neutron images of imploding laser fusion targets. Alignment was achieved using a laser, a 2 mm diameter glass sphere, and a pair of lenses. With this technique, a 6 cm long aperture was pointed with an accuracy of 68 microradians and coaxially aligned with a target and detector separated by 10.5 meters. The alignment technique is described and critical features are discussed.
A modeling study of the effect of stress state on void linking during ductile fracture

Abstract The deformation and fracture behavior of sheet specimens containing either pairs of “pseudo”-random arrays of equi-sized holes has been examined in both uniaxial and equal-biaxial tension utilizing experiment as well as computer simulation. Our results show for this plane-stress situation that hole linking is always caused by flow localization within the ligaments between neighboring holes. The imposed strains to initiate flow localization and subsequent ligament failure are sensitive to stress state (uniaxial versus biaxial) and the location of the neighboring hole(s). A significant observation is the influence of stress state on the multidirectionality of hole linking paths: specifically, increasing the biaxial component of the stress state increases the number of holes that can participate in a hole-linking process. A related implication is that the strain range over which void linking occurs decreases with increasing triaxiality of the stress state; in effect, after the initiation of void linking, its propagation is accelerated under biaxial or triaxial tension.
Quantum algorithm for a generalized hidden shift problem

Consider the following generalized hidden shift problem: given a function f on {0,..., M - 1} x ZN promised to be injective for fixed b and satisfying f(b, x) = f(b + 1,x + s) for b = 0, 1,..., M - 2, find the unknown shift s e ZN. For M = N, this problem is an instance of the abelian hidden subgroup problem, which can be solved efficiently on a quantum computer, whereas for M = 2, it is equivalent to the dihedral hidden subgroup problem, for which no efficient algorithm is known. For any fixed positive e, we give an efficient (i.e., poly(log N)) quantum algorithm for this problem provided M ≥ Ne. The algorithm is based on the "pretty good measurement" and uses H. Lenstra's (classical) algorithm for integer programming as a subroutine.
A Conditional Luminosity Function Model of the Cosmic Far-Infrared Background Anisotropy Power Spectrum

The cosmic far-infrared background (CFIRB) is expected to be generated by faint, dusty star-forming galaxies during the peak epoch of galaxy formation. The anisotropy power spectrum of the CFIRB captures the spatial distribution of these galaxies in dark matter halos and the spatial distribution of dark matter halos in the large-scale structure. Existing halo models of CFIRB anisotropy power spectrum either are incomplete or lead to halo model parameters that are inconsistent with the galaxy distribution selected at other wavelengths. Here, we present a conditional luminosity function approach to describe the far-IR bright galaxies. We model the 250 {mu}m luminosity function and its evolution with redshift and model-fit the CFIRB power spectrum at 250 {mu}m measured by the Herschel Space Observatory. We introduce a redshift-dependent duty cycle parameter so that we are able to estimate the typical duration of the dusty star formation process in the dark matter halos as a function of redshifts. We find that the duty cycle of galaxies contributing to the far-IR background is 0.3-0.5 with a dusty star formation phase lasting for {approx}0.3-1.6 Gyr. This result confirms the general expectation that the far-IR background is dominated by star-forming galaxies in an extended phase, not brightmore » starbursts that are driven by galaxy mergers and last {approx}10-100 Myr. The halo occupation number for satellite galaxies has a power-law slope that is close to unity over 0 10{sup 10} L {sub Sun} is 2 Multiplication-Sign 10{sup 11} M {sub Sun} and 3 Multiplication-Sign 10{sup 10} M {sub Sun} at z = 1 and 2, respectively. Integrating over the galaxy population with L {sub 250} > 10{sup 9} L {sub Sun }, we find that the cosmic density of dust residing in the dusty, star-forming galaxies is responsible for the background anisotropies {Omega}{sub dust} {approx} 3 Multiplication-Sign 10{sup -6} to 2 Multiplication-Sign 10{sup -5}, relative to the critical density of the universe.« less
Open questions in high-energy spin physics

I describe a few of the most exciting open questions in high energy spin physics. After a brief look at (g - 2)μ and the muon electric dipole moment, I concentrate on QCD spin physics. Pressing questions include the interpretation of new asymmetries seen in semi-inclusive DIS, measuring the polarized gluon and quark transversity distributions in the nucleon, testing the DHGHY Sum Rule, measuring the orbital angular momentum in the nucleon, and many others which go beyond the space and time allotted for this talk.
Bel-Robinson energy and constant mean curvature foliations

An energy estimate is proved for the Bel-Robinson energy along a constant mean curvature foliation in a spatially compact vacuum spacetime, assuming an \( L^{\infty} \) bound on the second fundamental form, and a bound on a spacetime version of Bel-Robinson energy.
Stardust in the Laboratory

Primitive meteorites and interplanetary dust particles contain small grains that originated in stellar outflows and supernova explosions. These μm- and sub-μm-sized presolar grains can be isolated and studied for their isotopic compositions in the laboratory. They are recognised as stardust by their isotopic compositions, which are completely different from those of the Solar System. They provide new information on stellar evolution, nucleosynthesis, mixing processes in asymptotic giant branch (AGB) stars and supernovae, and Galactic chemical evolution. Red giants, AGB stars, Type II supernovae and possibly novae have been identified as stellar sources of the grains. Of the eight nuclear processes proposed by Burbidge et al. (1957), signatures of all except the r-process can be found in presolar dust grains.
Methods for the evaluation of a hinge pin in a clapper support of a check valve

Typical methods for the evaluation of a hinge pin used in a clapper support of a check valve are presented. For clarity, an example is provided to show the application of the equations.
Improved Procedures for the Generation of Diborane from Sodium Borohydride and Boron Trifluoride

Improved procedures for the generation of diborane by the reaction of NaBH4 in triglyme or tetraglyme with the BF3 adducts of di-n-butyl ether, tert-butyl methyl ether, monoglyme, dioxane, and tetrahydropyran were developed. In these systems, generation of diborane requires 2-4 h at 25 degrees C (faster reactions take place at 50 degrees C). The byproduct NaBF4 precipitates from the reaction mixture at 25 degrees C as the reaction proceeds. The high-boiling glyme can be conveniently separated from the lower boiling carrier ethers by simple distillation of the latter. On the other hand, diborane was generated very slowly or not generated using the addition of each of six boron trifluoride-etherates (di-n-butyl ether, tert-butyl methyl ether, tetrahydrofuran, tetrahydropyran, dioxane, and monoglyme) to suspensions of sodium borohydride in the corresponding ether. However, diborane was generated rapidly and quantitatively by the addition of NaBH4 in triglyme (or tetraglyme) to the BF3 adduct of triglyme (or tetraglyme) at room temperature. No solid precipitation occurs during the reaction, making it convenient for large-scale applications. The pure solvent triglyme (or tetraglyme) can be easily recovered and recycled by either crystallizing or precipitating NaBF4 from the generation flask. New procedures for the generation of diborane were also developed by the reaction of NaBF4 with NaBH4 in triglyme (or tetraglyme) in the presence of Lewis acids such as AlCl3 and BCl3.
Peptide targeting of fluorescein-based sensors to discrete intracellular locales

Fluorescein-based sensors are the most widely applied class of zinc probes but display adventitious localization in live cells. We present here a peptide-based localization strategy that affords precision in targeting of fluorescein-based zinc sensors. By appending the zinc-selective, reaction-based probe Zinpyr-1 diacetate (DA-ZP1) to the N-terminus of two different targeting peptides we achieve programmable localization and avoid unwanted sequestration within acidic vesicles. Furthermore, this approach can be generalized to other fluorescein-based sensors. When appended to a mitochondrial targeting peptide, the esterase-activated profluorophore 2′,7′-dichlorofluorescein diacetate can be used effectively at concentrations four-times lower than previously reported for analogous, non-acetylated derivatives. These results demonstrate on-resin or in-solution esterification of fluorescein to be an effective strategy to facilitate peptide-based targeting in live cells.
Application of a Viscous-Inviscid Interaction Procedure to Predict Separated Flows With Heat Transfer

A viscous-inviscid interaction procedure is described for predicting heat transfer in separated flows. The separating flow in a rearward-facing step/asymmetric channel expansion is considered. For viscous regions, the boundary-layer momentum and continuity equations are solved inversely in a coupled manner by a finite-difference numerical scheme. The streamwise convective term is altered to permit marching the solution through regions of reversed flow. The inviscid flow is computed by numerically solving the Laplace equation for stream-function in the region bounded by the displacement surfaces used in the inverse boundary-layer solution. The viscous and inviscid solutions are repeated iteratively until the edge velocities obtained from both solutions are in agreement. Predictions using this method compare favorably with experimental data and other predictions.
On replacement axioms for the Jacobi identity for vertex algebras and their modules

We discuss the axioms for vertex algebras and their modules, using formal calculus. Following certain standard treatments, we take the Jacobi identity as our main axiom and we recall weak commutativity and weak associativity. We derive a third companion property that we call “weak skew-associativity”. This third property in some sense completes an S3-symmetry of the axioms, which is related to the known S3-symmetry of the Jacobi identity. We do not initially require a vacuum vector, which is analogous to not requiring an identity element in ring theory. In this more general setting, one still has a property, occasionally used in standard treatments, which is closely related to skew-symmetry, which we call “vacuum-free skew-symmetry”. We show how certain combinations of these properties are equivalent to the Jacobi identity for both vacuum-free vertex algebras and their modules. We then specialize to the case with a vacuum vector and obtain further replacement axioms. In particular, in the final section we derive our main result, which says that, in the presence of certain minor axioms, the Jacobi identity for a module is equivalent to either weak associativity or weak skew-associativity. The first part of this result has appeared previously and has been used to show the (nontrivial) equivalence of representations of and modules for a vertex algebra. Many but not all of our results appear in standard treatments; some of our arguments are different from the usual ones.
Does Human Capital Raise Farm or Non-farm Earning More? New Insight from Rural Pakistan Panel Survey

This study explores how human capital affects farm household earnings using two tools to refine measurement of human capital effects. First, it employs a two-sector model to allow the allocation of family labor between farm and non-farm activities. Second, it accounts for village fixed effects to evaluate whether results from panel data differ meaningfully from a cross-sectional data analysis with local binary variables. The results show that education has a negligible effect on farm earnings; instead, experience appears to be the principal channel by which human capital affects agricultural performance in a traditional rural setting. Our results also suggest that prior models that fail to separate non-farm activities spuriously exaggerated the effect of education to the farm sector. In addition, typical cross-sectional analyses that ignore fixed effects may cause the effects of education on rural household earnings to be significantly overstated. The fact that panel data regressions accounting for village-level fixed effects found only one instance of education raising earnings the effect of literacy on non-farm income suggests that considerable heterogeneity may have been ignored in cross-sectional data analyses, especially ones that omitted village binary variables.
Degree Reduction for NURBS Symbolic Computation on Curves

Symbolic computation of NURBS plays an important role in many areas of NURBS-based geometric computation and design. However, any nontrivial symbolic computation, especially when rational B-splines are involved, would typically result in B-splines with high degrees. In this paper we develop degree reduction strategies for NURBS symbolic computation on curves. The specific topics we consider include zero curvatures and critical curvatures of plane curves, various ruled surfaces related to space curves, and point/curve bisectors and curve/curve bisectors.
Design of a Low Aspect Ratio Transonic Compressor Stage Using CFD Techniques

A transonic compressor stage has been designed for the Naval Postgraduate School Turbopropulsion Laboratory. The design relied heavily on CFD techniques while minimizing conventional empirical design methods. The low aspect ratio (1.2) rotor has been designed for a specific head ratio of .25 and a tip relative inlet Mach number of 1.3. Overall stage pressure ratio is 1.56. The rotor was designed using an Euler code augmented by a distributed body force model to account for viscous effects. This provided a relatively quick-running design tool, and was used for both rotor and stator calculations. The initial stator sections were sized using a compressible, cascade panel code. In addition to being used as a case study for teaching purposes, the compressor stage will be used as a research stage. Detailed measurements, including non-intrusive LDV, will be compared with the design computations, and with the results of other CFD codes, as a means of assessing and improving the computational codes as design tools.
Distributed algorithms for spectrum allocation, power control, routing, and congestion control in wireless networks

We develop distributed algorithms to allocate resources in multi-hop wireless networks with the aim of minimizing the total cost. In order to observe the fundamental duplexing constraint that co-located transmitters and receivers cannot operate simultaneously on the same frequency band, we first devise a spectrum allocation scheme that divides the whole spectrum into multiple sub-bands and activates conflict-free links on each sub-band. We show that the minimum number of required sub-bands grows asymptotically at a logarithmic rate with the chromatic number of network connectivity graph. A simple distributed and asynchronous algorithm is developed to feasibly activate links on the available sub-bands. Given a feasible spectrum allocation, we then develop node-based distributed algorithms for optimally controlling the transmission powers on active links for each sub-band, jointly with traffic routes and user input rates in response to channel states and traffic demands. We show that under specified conditioans, the algorithms asymptotically converge to the optimal operating point.
Nutrition research to affect food and a healthy life span

Proper nutrition offers one of the most effective and least costly ways to decrease the burden of many diseases and their associated risk factors, including obesity. Nutrition research holds the key to increasing our understanding of the causes of obesity and its related comorbidities and thus holds promise to markedly influence global health and economies. After outreach to 75 thought leaders, the American Society for Nutrition (ASN) convened a Working Group to identify the nutrition research needs whose advancement will have the greatest projected impact on the future health and well-being of global populations. ASN's Nutrition Research Needs focus on the following high priority areas: 1) variability in individual responses to diet and foods; 2) healthy growth, development, and reproduction; 3) health maintenance; 4) medical management; 5) nutrition-related behaviors; and 6) food supply/environment. ASN hopes the Nutrition Research Needs will prompt collaboration among scientists across all disciplines to advance this challenging research agenda given the high potential for translation and impact on public health. Furthermore, ASN hopes the findings from the Nutrition Research Needs will stimulate the development and adoption of new and innovative strategies that can be applied toward the prevention and treatment of nutrition-related diseases. The multidisciplinary nature of nutrition research requires stakeholders with differing areas of expertise to collaborate on multifaceted approaches to establish the evidence-based nutrition guidance and policies that will lead to better health for the global population. In addition to the identified research needs, ASN also identified 5 tools that are critical to the advancement of the Nutrition Research Needs: 1) omics, 2) bioinformatics, 3) databases, 4) biomarkers, and 5) cost-effectiveness analysis.
The Great Recession, Decline, and Rebound in Household Wealth for the Near-Retirement Population

This article uses data from the Health and Retirement Study (HRS) to examine the effects of the Great Recession on wealth held by the near-retirement-age population over 2006–2012. Despite a severe decline in asset values during this period, the wealth of early Baby Boomers (ages 51 to 56 in 2004), fell by only 3.6%. Much of the decline was cushioned by the wealth represented by Social Security and defined benefit (DB) pensions. The rebound in asset values observed between 2010 and 2012 mitigated, but did not erase, the losses experienced earlier. Those in the highest wealth deciles, with a larger share of financial assets, were hurt most severely. Unlike those in lower wealth deciles, they have yet to regain the wealth lost during the recession. Although the losses in assets imposed by the Great Recession were relatively modest, the failure of assets to grow above their initial levels has imposed a cost on recent retirees.