cssi/SciSciGPT-SciSciNet huggingface dataset:
Vertically Extended Neutral Gas in the Massive Edge-on Spiral NGC 5746

We present Very Large Array 21 cm observations of the massive edge-on spiral galaxy NGC 5746. This galaxy has recently been reported to have a luminous X-ray halo, which has been taken as evidence of residual hot gas, as predicted in galaxy formation scenarios. Such models also predict that some of this gas should undergo thermal instabilities, leading to a population of warm clouds falling onto the disk. If so, then one might expect to find a vertically extended neutral layer. We detect a substantial high-latitude component, but conclude that almost all of its mass of 1.2- -->1.6 ? 109 -->M? most likely resides in a warp. Four features far from the plane containing about -->108 -->M? are found at velocities distinct from this warp. These clouds may be associated with the expected infall, although an origin in a disk-halo flow cannot be ruled out, except for one feature which is counterrotating. The warp itself may be a result of infall according to recent models. But clearly this galaxy lacks a massive, lagging neutral halo as found in NGC 891. The disk H I is concentrated into two rings of radii -->1.5' and -->3'. Radial inflow is found in the disk, probably due to the bar in this galaxy. A nearby member of this galaxy group, NGC 5740, is also detected. It shows a prominent one-sided extension which may be the result of ram pressure stripping.
Market Transition and the Firm: Institutional Change and Income Inequality in Urban China

This paper examines how the rise of a market economy in urban China redefines the rules governing economic activities and affects on earnings inequality. We identify three causal mechanisms linked to institutional change that are transforming the firm's employment practices: the higher marginal productivity of a private enterprise economy relative to state-owned enterprises, competition by firms for skilled and semi-skilled labor following emergence of labor markets and the end of state monopoly on labor allocation, and increased emphasis on merit-based reward systems in firms. Analyses of survey data from urban China show how these three causal mechanisms stemming from the transition to a market economy contribute to new patterns of earnings differentiation that increase income returns to human capital and private-sector entrepreneurship.
Continuous Process For Recycling of Polyurethane Foam

The investigation deals with the recycling of high resiliency polyurethane (PU) foam by the application of high-power ultrasound in a continuous ultrasonic reactor. The foam has been decrosslinked at various screw speeds and various amplitudes, then blended at different ratios with the virgin polyurethane rubber (PUR) and cured. The die pressure and the total power consumption have been recorded as a function of processing conditions. Rheological and mechanical properties, hardness as well as gel fraction and crosslink density of the decrosslinked foam and cured blends have been measured and compared in an attempt to find out the optimum condition for decrosslinking. Blends have also been prepared using different proportions of ground samples and virgin rubber, and a comparison of the properties between these blends and the blends of the decrosslinked foam has been carried out. The results show that compared to the ground samples, the blends of the decrosslinked samples are easier to mix and exhibit enhanced properties.
Public Finance and Individual Preferences over Globalization Strategies

Do individual preferences towards alternative globalization strategies vary across different public-finance regimes? In the absence of tax and spending policies, freer immigration and trade for a country would often be supported by similar groups thanks to similar impacts on labor demand and thus labor income. Government policies that redistribute income may, however, alter the distributional politics. In particular, immigrants may pay taxes and receive public services. Imports, obviously, can do neither of these. This suggests quite different political coalitions may organize around trade and immigration. In this paper we develop a framework for examining how pre-tax and post-tax cleavages may differ across globalization strategies and also fiscal jurisdictions. We then apply this framework to the case of individual immigration and trade preferences across U.S. states. Substantial cross-state variation in immigrant presence and welfare eligibility allows a rich examination of theoretical predictions. We have two main findings. First, high exposure to immigrant fiscal pressures reduces support for freer immigration among natives, especially the more-skilled. The magnitude of this post-tax fiscal cleavage is comparable to the pre-tax labor-market effects of skill itself. Second, there is no public-finance variation in opinion over trade policy, consistent with the data that U.S. trade policy has negligible fiscal-policy impacts. Public-finance concerns appear to be crucial in shaping opinions towards alternative globalization strategies.
INTERLIBRARY LOAN: AN OLD IDEA IN A NEW SETTING

Today it is access rather than ownership which is the important question to users. Timely delivery of information is costly, but the price must be paid. Library users have been trained by librarians to be passive and to expect delays in their requests for information. This attitude springs from acceptance of interlibrary loan as a moral precept rather than a pragmatic commodity, an idea which now conflicts with librarians' responsibilities as managers of an accountable resource. Accepting the premise that resource sharing is the priority of the future, librarians must determine ILL costs honestly, in order to provide the supplier with a fair incentive. They must shape their procedures to the needs of their clients and they must allow for ILL as an alternative to purchase in their acquisition budgets. Since ILL is only another form of acquisition (albeit ‘temporary acquisition’) it is both irrational and unfair to charge clients for this service. If ILL is worth doing, it is worth doing well, ensuring timely, high quality service. ILL should take its place as a normal and necessary element of any library's acquisition policy: no library is an island.
Biocompatibility and drug delivery systems

Drug delivery technology has emerged as an important focus of biotechnological research and commercial enterprise. While much attention is justifiably focused on the design and effectiveness of drug delivery devices, the nature of their interaction with surrounding tissues – their biocompatibility – is crucial. Here we discuss biocompatibility, specifically as it relates to drug delivery systems, which differ from other biomaterial-based devices by possibly containing large quantities of drugs with their own effects on tissues.
UNIVERSAL TREE-GRADED SPACES AND ASYMPTOTIC CONES

We define and give explicit construction of a universal tree-graded space with a given collection of pieces. We apply that to proving uniqueness of asymptotic cones of relatively hyperbolic groups whose peripheral subgroups have unique asymptotic cones. Modulo the Continuum Hypothesis, we show that if an asymptotic cone of a geodesic metric space is homogeneous and has cut points, then it is the universal tree-graded space whose pieces are maximal connected subsets without cut points. Thus it is completely determined by its collection of pieces.
THEMIS observes possible cave skylights on Mars

[1] Seven possible skylight entrances into Martian caves were observed on and around the flanks of Arsia Mons by the Mars Odyssey Thermal Emission Imaging System (THEMIS). Distinct from impact craters, collapse pits or any other surface feature on Mars, these candidates appear to be deep dark holes at visible wavelengths while infrared observations show their thermal behaviors to be consistent with subsurface materials. Diameters range from 100 m to 225 m, and derived minimum depths range between 68 m and 130 m. Most candidates seem directly related to pit-craters, and may have formed in a similar manner with overhanging ceilings that remain intact.
Market Value Maximization and Markov Dynamic Programming

This paper shows how an operational method for solving dynamic programs can be used, in some cases, to solve the problem of maximizing a firm's market value. The problem is formulated as a Markov decision problem that can be solved via linear programming. The paper shows how to calculate or estimate the state-contingent prices that are used to value the firm. In addition, the paper points out how states can be aggregated to make the solution technique more practical. The paper's final section contains a specific example.
A computationally compact representation of Magnetic-Apex and Quasi-Dipole coordinates with smooth base vectors

[1] Many structural and dynamical features of the ionized and neutral upper atmosphere are strongly organized by the geomagnetic field, and several magnetic coordinate systems have been developed to exploit this organization. Quasi-Dipole coordinates are appropriate for calculations involving horizontally stratified phenomena like height-integrated currents, electron densities, and thermospheric winds; Modified Apex coordinates are appropriate for calculations involving electric fields and magnetic field-aligned currents. The calculation of these coordinates requires computationally expensive tracing of magnetic field lines to their apexes. Interpolation on a precomputed grid provides faster coordinate conversions, but requires the overhead of a sufficiently fine grid, as well as finite differencing to obtain coordinate base vectors. In this paper, we develop a compact and robust representation of the transformation from geodetic to Quasi-Dipole (QD), Apex, and Modified Apex coordinates, by fitting the QD coordinates to spherical harmonics in geodetic longitude and latitude. With this representation, base vectors may be calculated directly from the expansion coefficients. For an expansion truncated at order 6, the fitted coordinates deviate from the actual coordinates by a maximum of 0.4°, and typically by 0.1°. The largest errors occur in the equatorial Atlantic region. Compared to interpolation on a pre-computed grid, the spherical harmonic representation is much more compact and produces smooth base vectors. An algorithm for efficiently and concurrently computing scalar and vector spherical harmonic functions is provided in the appendix. Computer code for producing the expansion coefficients and evaluating the fitted coordinates and base vectors is included in the auxiliary material.
SCALING LAWS AND TEMPERATURE PROFILES FOR SOLAR AND STELLAR CORONAL LOOPS WITH NON-UNIFORM HEATING

The bulk of solar coronal radiative loss consists of soft X-ray emission from quasi-static loops at the cores of active regions. In order to develop diagnostics for determining the heating mechanism of these loops from observations by coronal imaging instruments, I have developed analytical solutions for the temperature structure and scaling laws of loop strands for a set of temperature- and pressure-dependent heating functions that encompass heating concentrated at the footpoints, uniform heating, and heating concentrated at the loop apex. Key results are that the temperature profile depends only weakly on the heating distribution—not sufficiently to be of significant diagnostic value—and that the scaling laws survive for this wide range of heating distributions, but with the constant of proportionality in the Rosner-Tucker-Vaiana scaling law (P 0 L ~ T 3 max) depending on the specific heating function. Furthermore, quasi-static solutions do not exist for an excessive concentration of heating near the loop footpoints, a result in agreement with recent numerical simulations. It is demonstrated that a generalization of the results to a set of solutions for strands with a functionally prescribed variable diameter leads to only relatively small correction factors in the scaling laws and temperature profiles for constant diameter loop strands. A quintet of leading theoretical coronal heating mechanisms is shown to be captured by the formalism of this paper, and the differences in thermal structure between them may be verified through observations. Preliminary results from full numerical simulations demonstrate that, despite the simplifying assumptions, the analytical solutions from this paper are accurate and stable.
Azacyclopropenylidenimine: a low energy dimer of hydrogen cyanide.

Using the INDO approach, semi-empirical quantum-mechanical calculations of the ground state energies of various proposed structures for the dimer of hydrogen cyanide suggest that azacyclopropenylidenimine (or 1-azirine-3-imine) is more stable than either iminoacetonitrile (by 46 kcal/mol) or aminocyanocarbene [by 111 kcal/mol (singlet) or 102 kcal/mol (triplet)]. It therefore seems likely that azacyclopropenylidenimine, formed by the carbenoid addition of hydrogen isocyanide, HNC, to HCN or by nucleophilic addition of cyanide ion to HCN followed by intramolecular cyclization and protonation, is a major intermediate in base-catalyzed reactions of hydrogen cyanide. Its existence in interstellar space is to be expected, together with HCN and HNC that have already been detected. It is further proposed that polymerization of azacyclopropenylidenimine was a key step in the atmospheric chemistry leading to the original formation of heteropolypeptides on Earth over four billion years ago.
Quest 123: a benchmarking system for technology assessment at NASA

Technology assessment is a difficult task at the Mission Control Center (MCC). The difficulty is inherent in the unavailability of structured information and exacerbated by the lack of a systematic assessment process. New technology deployment to the MCC requires testing and certification in three labs: Quest 1, 2, and 3. The Mission Control Center Systems (MCCS) architecture team, a multidisciplinary group of MCC experts and scientists is chartered to redefine the next generation of MCCS by developing a systematic process to assess and certify new technologies. Quest 123 is a benchmarking tool that was successfully implemented at the Johnson Space Center to assess and certify new technology initiatives for each lab before final deployment to the MCC. Quest 123 integrates the analytic hierarchy process with an additive multi‐criteria decision‐making model into a dynamic benchmarking framework.
QCD at Finite Baryon Density : Chiral Symmetry Restoration and Color Superconductivity

We use a variational procedure to study finite density QCD in an approximation in which the interaction between quarks is modelled by that induced by instantons. We find that uniform states with conventional chiral symmetry breaking have negative pressure with respect to empty space at all but the lowest densities, and are therefore unstable. This is a precisely defined phenomenon which motivates the basic picture of hadrons assumed in the MIT bag model, with nucleons as droplets of chiral symmetry restored phase. This suggests that the phase transition to a chirally symmetric phase occurs by percolation of preexisting droplets of the symmetric phase, and in these proceedings we expand upon our previous presentation of this observation. At all densities high enough that the chirally symmetric phase fills space, color symmetry is broken by the formation of a (qq) condensate of quark Cooper pairs. A plausible ordering scheme leads to a substantial gap in a Lorentz scalar channel involving quarks of two colors.
Testing M(atrix) theory at two loops

Abstract I discuss the relation between M-theory and M(atrix)-theory in flat space by considering the effective potential for the scattering of two groups of D0-branes in both theories. An explicit calculation of this potential up to two loop order in M(atrix)-theory reveals a fascinating agreement.
Whence the Minkowski momentum

Abstract Electromagnetic waves carry the Abraham momentum, whose density is given by pEM = S(r,t) / c2. Here S(r,t) = E(r,t) × H(r,t) is the Poynting vector at point r in space and instant t in time, E and H are the local electromagnetic fields, and c is the speed of light in vacuum. The above statement is true irrespective of whether the waves reside in vacuum or within a ponderable medium, which medium may or may not be homogeneous, isotropic, transparent, linear, magnetic, etc. When a light pulse enters an absorbing medium, the force experienced by the medium is only partly due to the absorbed Abraham momentum. This absorbed momentum, of course, is manifested as Lorentz force (while the pulse is being extinguished within the absorber), but not all the Lorentz force experienced by the medium is attributable to the absorbed Abraham momentum. We consider an absorptive/reflective medium having the complex refractive index n2 + iκ2, submerged in a transparent dielectric of refractive index n1, through which light must travel to reach the absorber/reflector. Depending on the impedance-mismatch between the two media, which mismatch is dependent on n1, n2, κ2, either more or less light will be coupled into the absorber/reflector. The dependence of this impedance-mismatch on n1 is entirely responsible for the appearance of the Minkowski momentum in certain radiation pressure experiments that involve submerged objects.
Reactions of sodium pentacarbonylrhenate(1 —) with activated acetylenes. Formation of rhenacyclobutenone complexes

Abstract The complexes Na[(CO) 4 ReC(R)C(CO 2 Me)C (O)] ( 1a , R  CO 2 Me; 1b , R  Me) are formed in the reaction of Na[Re(CO) 5 ] with RCCCO 2 Me at room temperature. The structure of 1a has been shown by X-ray diffraction to contain a rhenacyclobutenone ring. Complex 1b is alkylated by Et 3 OPF 6 at the ketonic oxygen, as determined crystallographically.
The Renormalization Group in Nuclear Physics

Modern techniques of the renormalization group (RG) combined with effective field theory (EFT) methods are revolutionizing nuclear many-body physics. In these lectures we will explore the motivation for RG in low-energy nuclear systems and its implementation in systems ranging from the deuteron to neutron stars, both formally and in practice. Flow equation approaches applied to Hamiltonians both in free space and in the medium will be emphasized. This is a conceptually simple technique to transform interactions to more perturbative and universal forms. An unavoidable complication for nuclear systems from both the EFT and flow equation perspective is the need to treat many-body forces and operators, so we will consider these aspects in some detail. Weʼll finish with a survey of current developments and open problems in nuclear RG.
Resistance Increases in Gold Aluminum Interconnects with Time and Temperature

Increases in the resistance of gold aluminum interconnects with time and temperature were investigated. Aluminum wife was ultrasonically bonded to Cr-Au and TiPd-Au thin-film metallization on ceramic substrates. The interconnects were exposed to temperatures from 150 to 300°C for times up to 400 h. The resistance of the interconnects was measured periodically during the exposure to elevated temperatures. There were significant increases in resistance on both types of metallization. Some measurements indicated electrically open interconnects, but the mechanical strength remained high. If systems containing gold aluminum interconnects axe anticipated to be processed or used at Or above 150°C, serious consideration should be given to the effects of increased resistance on circuit performance.
Optimal Image Reconstruction in Radio Interferometry

We introduce a method for analyzing radio interferometry data that produces maps that are optimal in the Bayesian sense of maximum posterior probability density, given certain prior assumptions. It is similar to maximum-entropy techniques, but with an exact accounting of the multiplicity instead of the usual approximation involving Stirling's formula. It also incorporates an Occam factor, automatically limiting the effective amount of detail in the map to that justified by the data. We use Gibbs sampling to determine, to any desired degree of accuracy, the multidimensional posterior density distribution. From this we can construct a mean posterior map and other measures of the posterior density, including confidence limits on any well-defined function of the posterior map.
Highly Enantioselective Conjugate Addition of Malonate and β-Ketoester to Nitroalkenes: Asymmetric C−C Bond Formation with New Bifunctional Organic Catalysts Based on Cinchona Alkaloids

The development of readily accessible bifunctional chiral catalysts is a desirable yet challenging goal in catalytic asymmetric synthesis. In this communication, we describe the development of a new class of readily accessible chiral bifunctional organic catalysts that could be derived in one or two steps in high yield from either quinidine or quinine. These catalysts have been shown to catalyze a highly enantioselective conjugate addition of methyl and ethyl malonates and β-ketoesters to a broad range of β-substituted nitroalkenes, an synthetically important C−C bond-forming reaction utilizing readily available starting materials. This new catalytic asymmetric reaction proceeds in 91−98% ee and 71−99% yield.
Numerical simulations of flutter and its suppression by active control

A method for predicting the unsteady, subsonic, aeroservoelastic response of a wing has been developed. All equations are solved simultaneously in the time domain by an iterative scheme based on a predictor-corrector method. The scheme allows a wide range of nonlinear aerodynamic and structural models to be used and subcritical, critical, and supercritical aeroelastic behavior can be modeled without restrictions to small disturbances or periodic motions. A general vortex lattice method is used to model the aerodynamics
A microbeam bending method for studying stress–strain relations for metal thin films on silicon substrates

Abstract We have developed a microbeam bending technique for determining elastic–plastic, stress–strain relations for thin metal films on silicon substrates. The method is similar to previous microbeam bending techniques, except that triangular silicon microbeams are used in place of rectangular beams. The triangular beam has the advantage that the entire film on the top surface of the beam is subjected to a uniform state of plane strain as the beam is deflected, unlike the standard rectangular geometry where the bending is concentrated at the support. To extract the average stress–strain relations for the film, we present a method of analysis that requires computation of the neutral plane for bending, which changes as the film deforms plastically. This method can be used to determine the elastic–plastic properties of thin metal films on silicon substrates up to strains of about 1%. Utilizing this technique, both yielding and strain hardening of Cu thin films on silicon substrates have been investigated. Copper films with dual crystallographic textures and different grain sizes, as well as others with strong 〈1 1 1〉 textures have been studied. Three strongly textured 〈1 1 1〉 films were studied to examine the effect of film thickness on the deformation properties of the film. These films show very high rates of work hardening, and an increase in the yield stress and work hardening rate with decreasing film thickness, consistent with current dislocation models.
Pavement Resurfacing Planning for Highway Networks: Parametric Policy Iteration Approach

This paper presents a modeling framework for planning pavement resurfacing activities on highway networks in the case of continuous pavement state, discrete time, and infinite horizon. Optimal resurfacing policies that minimize discounted life-cycle costs are obtained by solving a multidimensional dynamic program, where travelers’ route choices and the agency’s resource allocation decisions are considered simultaneously. To reduce computational difficulty, policy iteration is used together with a parametric function approximation technique. Numerical examples show that the proposed approach solves the planning problem efficiently. The effect of various factors (travelers’ route choice, agency budget, etc.) on the optimal policies is also analyzed.
Development of ambient temperature secondary lithium cells

Abstract Under a NASA-OAST sponsored program, JPL is developing ambient temperature secondary lithium cells for future spacecraft applications. Prior studies on
Synthetic applications of fluorous solid-phase extraction (F-SPE).

1.1. Synthesis is reaction and separation The enterprise of organic synthesis is a collective endeavor involving reaction and separation followed by identification and analysis.1 The “reaction and separation stage” produces a new organic molecule while the “identification and analysis stage” proves what the molecule is and how pure it is. The yield of every organic reaction depends on both the efficiency of the underlying reaction and the ability to recover the target product in pure form from the reaction mixture. Reaction methods have evolved and improved dramatically over the past decades and continue to do so. On the other hand, while they continued to be refined, the core separation methods that synthetic chemists routinely use have not change for a decade or more. The concept of the “ideal reaction” serves as an inspiring, if unattainable, goal for basic research in synthesis.2 In the trenches (the labs), reactions are usually a means to an end (chemical and drug discovery), and chemists tend to spend more time searching, hoping and wishing for the “ideal separation”1a,b. It is rare not every day that a new, generally applicable separation method comes along. The purpose of this Report is to provide an overview of the increasingly popular new separation technique of fluorous solid-phase extraction (F-SPE). Though it is still less than a decade old,3 the technique has matured rapidly and is now ready for prime time, as illustrated by the expanding uses over the last 2–3 years.4 After a brief introduction of two varieties of F-SPE—standard and reverse—we provide comprehensive tabular collections of published uses in small molecule synthesis that are intended to illustrate both the scope of the method and the diverse array of reagents and materials that are now available. We close by providing interested readers with practical information on how to conduct an F-SPE.
D-branes in topological minimal models: the Landau-Ginzburg approach

We study D-branes in topologically twisted N = 2 minimal models using the Landau-Ginzburg realization. In the cases of A and D-type minimal models we provide what we believe is an exhaustive list of topological branes and compute the corresponding boundary OPE algebras as well as all disk correlators. We also construct examples of topological branes in E-type minimal models. We compare our results with the boundary state formalism, where possible, and find agreement.
A multistage stochastic programming approach with strategies for uncertainty reduction in the synthesis of process networks with uncertain yields

We consider in this paper the synthesis of process networks with time-varying uncertain yields in which investment in pilot plants can be considered to reduce uncertainty of the yields. We formulate this problem as a multistage stochastic program with decision dependent elements where investment strategies are considered to reduce uncertainty, and time-varying distributions are used to describe uncertainty. We propose a new mixed-integer/disjunctive programming model which is reformulated as a mixed-integer linear program. Since the model can only be solved through an LP-based branch and bound for smaller instances, we propose a duality-based branch and bound algorithm for solving larger problems. Two numerical examples are presented to illustrate the application of the proposed method.
An electron optical technique for large-capacity random-access memories

Memories of the electron beam recording type have many desirable features for large capacity applications. At the Wescon Conference of 1958, the author proposed a class of electron optical memories of very high storage density under the title, "Information Storage in Microspace."
CATEGORICITY FROM ONE SUCCESSOR CARDINAL IN TAME ABSTRACT ELEMENTARY CLASSES

We prove that from categoricity in λ+ we can get categoricity in all cardinals ≥ λ+ in a χ-tame abstract elementary classe $\mathcal{K}$ which has arbitrarily large models and satisfies the amalgamation and joint embedding properties, provided $\lambda > {\rm LS}(\mathcal{K})$ and λ ≥ χ. For the missing case when $\lambda ={\rm LS}(\mathcal{K})$, we prove that $\mathcal{K}$ is totally categorical provided that $\mathcal{K}$ is categorical in ${\rm LS}(\mathcal{K})$ and ${\rm LS}(\mathcal{K})^+$.
Telling the Difference: Nineteenth-Century Legal Narratives of Racial Taxonomy

“Telling the Difference” focuses on two legal opinions from the nineteenth century that carefully distinguish between those who should be racially marked as nonwhite and those who should not. In the first instance, a Michigan judge decides the appropriate “blood fraction” of African-American heritage that would prohibit a free man from voting. In the second, a New Mexico judge rules that the Native Americans of Cochiti Pueblo are not legally “Indians, ” and therefore not entitled to federal protection of their land. The article uses these examples to advance two central claims: that we must pay close attention to the narrative logic of racial identification in order to understand the powerful contradictions still at the heart of our conversations about race, and that in doing so we should consider that race has always been multiply constructed in the United States.
On Colmez’s product formula for periods of CM-abelian varieties

Colmez conjectured a product formula for periods of abelian varieties with complex multiplication by a field \(K\), analogous to the standard product formula in algebraic number theory. He proved this conjecture up to a rational power of 2 for \(K/\mathbb{Q }\) abelian. In this paper, we complete the proof of Colmez for \(K/\mathbb{Q }\) abelian by eliminating this power of 2. Our proof relies on analyzing the Galois action on the De Rham cohomology of Fermat curves in mixed characteristic \((0,2)\), which in turn relies on understanding the stable reduction of \(\mathbb Z /2^n\)-covers of the projective line, branched at three points.
Comparison of the predictive capabilities of several turbulence models

Four turbulence models are evaluated for transonic separated flows using two well-established solvers, one upwind and one central difference. The equilibrium model of Baldwin-Lomax predicts separated-flow shock locations too far aft. The effects of several modifications to the half-equation model of Johnson-King are explored in detail, and different versions of the model are compared. Good results for twoand three-dimensional flows can be obtained using two different versions of this model. The one-equation models of Baldwin-Barth and Spalart-Allmaras perform well for airfoil flows, but can predict the shock too far forward at the outboard stations of a separated wing. The effects of numerical truncation error are assessed using grid-refinement studies in combination with varying the numerical dissipation levels in both codes.
The gradient adaptive split lattice algorithm

The authors present a new algorithm for adaptive filtering of autoregressive processes, based on a three-term recurrence that replaces the lattice equations of the gradient adaptive lattice (GAL) algorithm of Griffiths (1977) and requires only half as many multiplications per recursion. They also present a single-stage convergence analysis and a numerical example comparing the new algorithm to the GAL. Its performance is similar to the GAL, while requiring less than 2/3 as many multiplications and additions. >
The Grid Bootstrap and the Autoregressive Model

A “grid” bootstrap method is proposed for confidence-interval construction, which has improved performance over conventional bootstrap methods when the sampling distribution depends upon the parameter of interest. The basic idea is to calculate the bootstrap distribution over a grid of values of the parameter of interest and form the confidence interval by the no-rejection principle. Our primary motivation is given by autoregressive models, where it is known that conventional bootstrap methods fail to provide correct first-order asymptotic coverage when an autoregressive root is close to unity. In contrast, the grid bootstrap is first-order correct globally in the parameter space. Simulation results verify these insights, suggesting that the grid bootstrap provides an important improvement over conventional methods. Gauss code that calculates the grid bootstrap intervals-and replicates the empirical work reported in this paper'is available from the author's Web page at www.ssc.wisc.edu˜bhansen
Cosmological Constraints from Hubble Parameter versus Redshift Data

We use the Simon et al. determination of the redshift dependence of the Hubble parameter to constrain cosmological parameters in three dark energy cosmological models. We consider the standard ΛCDM model, the XCDM parameterization of the dark energy equation of state, and a slowly rolling dark energy scalar field with an inverse power-law potential. The constraints are restrictive, consistent with those derived from Type Ia supernova redshift-magnitude data, and complement those from galaxy cluster gas mass fraction versus redshift data.
Estimating the variations and autocorrelations in dietary intakes on weekdays and weekends

The high incidence of breast cancer in the U.S. and the possible link with dietary fat has led to the development of educational programmes for reducing women's fat intakes by agencies such as the National Cancer Institute and the U.S. Department of Agriculture. In this paper, we analyse the effects of an intervention on the intakes of 12 nutrients by 37 women in the Houston area. We estimate a dynamic random effects model by maximum likelihood to estimate the between and the within variations and the autocorrelations using 7 consecutive food records before and after the intervention programme. The main findings are that the pattern of within variations differs during weekdays and weekends. Secondly, the mean intakes of nutrients such as β-carotene and ascorbic acid tend to be lower on weekends. Lastly, the intervention programme reduced the overall fat intakes and also increased the variation in the consumption of foods high in fats during weekdays. We discuss the implications of the results for the design of further studies.
Translating graphs by mean curvature flow

The aim of this work is studying translating graphs by mean curvature flow in $$\mathbb {R}^3$$ . We prove non-existence of complete translating graphs over bounded domains in $$\mathbb {R}^2$$ . Furthermore, we show that there are only three types of complete translating graphs in $$\mathbb {R}^3$$ ; entire graphs, graphs between two vertical planes, and graphs in one side of a plane. In the last two types, graphs are asymptotic to planes next to their boundaries. We also prove stability of translating graphs and then we obtain a pointwise curvature bound for translating graphs in $$\mathbb {R}^3$$ .
Algebraic unimodular counting

We study algebraic algorithms for expressing the number of non-negative integer solutions to a unimodular system of linear equations as a function of the right hand side. Our methods include Todd classes of toric varieties via Grobner bases, and rational generating functions as in Barvinok's algorithm. We report polyhedral and computational results for two special cases: counting contingency tables and Kostant's partition function.
DARK ENERGY AND THE HUBBLE AGE

I point out that an effective upper limit of approximately 20(0.2/Ωm)1/2 Gyr (for a Hubble constant of 72 km s-1 Mpc-1), or alternatively, 1.49(0.2/Ωm)1/2 for the H0-independent quantity H0t0, exists on the age of the universe, essentially independent of the unknown equation of state of the dominant dark energy component in the universe. If astrophysical constraints on the age of the universe can convincingly reduce the upper limit to well below this value, a useful lower limit on the equation of state parameter w for this component can be obtained. Direct dating by stars does not provide a useful constraint, but model-dependent cosmological limits from supernovae and the CMB observations can do so.
Total synthesis of (±)-sesquicarene☆

Abstract Two synthetic routes from farnesol to (±)-sesquicarene (1) involving intramolecular carbenoid cycliziation of acyclic precursors as the key step are described. The diazoketone (4) derived from 2,6,10-trimethylundeca-5,9-dienoicacid (14) undergoes efficient copper-catalyzed cyclization to sesquicarone (5). Sesquicarene is obtained by pyrolysis of the sodium salt of the p-toluenesulfonylhydrazone of 5. A direct cyclization of farnesal p-toluenesulfonylhydrazone (17) also affords (±)-1 in low yield.
The construction of spinors in geometric algebra

Abstract The relationship between spinors and Clifford (or geometric) algebra has long been studied, but little consistency may be found between the various approaches. However, when spinors are defined to be elements of the even subalgebra of some real geometric algebra, the gap among algebraic, geometric, and physical methods is closed. Spinors are developed in any number of dimensions from a discussion of spin groups, followed by the specific cases of U (1), SU (2), and SL ( 2 , C ) spinors. The physical observables in Schrodinger–Pauli theory and Dirac theory are found, and the relationship between Dirac, Lorentz, Weyl, and Majorana spinors is made explicit. The use of a real geometric algebra, as opposed to one defined over the complex numbers, provides a simpler construction and advantages of conceptual and theoretical clarity not available in other approaches.
Crisis in the French Labour Movement a Grassroots Perspective

To the outside observer the French labour movement has undergone a puzzling transformation in recent years. From May 1968 to May 1981 French workers and their unions appear to have changed their very character, leading many observers to speak of a ‘crisis’ in the labour movement. Consider: in May 1968, following the lead of radicalised students who were denouncing everything from campus curfews to the capitalist system, over half of all workers went out on strike. In many cases they seized factories, set up strike committees and put forth demands for workers’ control of production (autogestion). Initially caught off guard by the spontaneous strikes the two largest trade union confederations, the Communist-affiliated Confederation Generale du Travail (CGT) and the formerly Catholic Confederation Francaise democratique du Travail (CFDT), soon joined the strikes and sought to gain control over the scope and direction of the workers’ protests.
Memory-scanning task performance in Alzheimer's disease.

Individuals with mild Alzheimer’s Disease (AD) and healthy normal control (NC) older adults performed a varied-set version of the Sternberg memory-scanning task with Set Sizes 1, 2, 3, and 4. The AD group (N=23) had slower and more variable reaction times (RT) than the NC group (N=38). RT differences between groups were bigger for NO than for YES responses. The linear relationship between RT and set size was not as strong for the AD group as for the NC group. However, in contrast to earlier studies with fewer subjects, participants with AD and healthy older individuals did not differ in the rate at which they scan items in the memory set.
Use of Potassium β-Trifluoroborato Amides in Suzuki-Miyaura Cross-Coupling Reactions

Potassium β-trifluoroborato amides were prepared and used as successful partners in Suzuki−Miyaura reactions with various aryl chlorides, including electron-rich and electron-poor derivatives, as well as several heteroaryl chloride partners.
Evaluating the Quality of Teaching and Learning at Lincoln University from the Student Viewpoint

This study aims to examine the quality of teaching at Lincoln University based on student perception. This research is a replica study of Abdul Hamid and Pihie (2004). The primary data collected from a questionnaire with 45 statements were organized into two categories: lecturer characteristics and lecturer competence. The result of the Cronbach’s alpha reliability test was 0.97, and both descriptive and inferential statistics showed heartening findings. Respondents generally agreed and were satisfied with the quality of teaching, with no significant difference as a whole based on gender (F= 0.69, p < 0.26). The author offers the following solutions: lecturers should take more responsibility in improving the quality of teaching; the school’s management should put lecturers under continuous development programs; and greater emphasis should be placed on student perception by examining their expectations about the quality of education. This research focuses on one private school, Lincoln University, which limits its generalizability. For future research, the author suggests utilizing text-based responses to gather rich data and narrative from the students’ point of view, as well as assessing lecturers’ academic degrees and contributions to the academic world, such as professorships and research.
Large Deviations in Quantum Lattice Systems: One-Phase Region

We give large deviation upper bounds, and discuss lower bounds, for the Gibbs-KMS state of a system of quantum spins or an interacting Fermi gas on the lattice. We cover general interactions and general observables, both in the high temperature regime and in dimension one.
Modeling the competition among air-travel itinerary shares: GEV model development

This study reports the results of aggregate air-travel itinerary share models estimated using data from all East West markets in the United States and Canada. These models predict airline ridership at the itinerary level and aid carriers in long and intermediate term decision-making. Official and comprehensive schedule and bookings data is used to estimate generalized extreme value models capturing the inter-itinerary competition dynamic along three dimensions: time of day, carrier and level-of-service (nonstop, direct, single-connect, double-connect). Models incorporate one, two or three of these dimensions simultaneously. Model structures considered include multinomial logit and variations of the nested logit model (two-level nested logit, two-level weighted nested logit, three-level nested logit, three-level weighted nested logit and nested weighted nested logit). Independent variables for the models measure various itinerary service characteristics such as level-of-service, connection quality, carrier attributes, aircraft type, and departure time. Additionally, the advanced models yield inverse logsum and/or weight parameter estimates capturing the underlying competitive dynamic among air-travel itineraries. The results are intuitive, and the advanced models outperform the more basic specifications with regard to statistical tests and behavioral interpretations, giving insight into the competitive dynamic of air-carrier itineraries.
Fading cognitive multiple-access channels with confidential messages

The fading cognitive multiple-access channel with confidential messages (MAC-CM) is investigated, in which two users attempt to transmit common information to a destination and user 1 also has confidential information intended for the destination. User 1 views user 2 as an eavesdropper and wishes to keep its confidential information as secret as possible from user 2. The multiple-access channel (both the user-to-user channel and the user-to-destination channel) is corrupted by multiplicative fading gain coefficients in addition to additive white Gaussian noise. The channel state information (CSI) is assumed to be known at both the users and the destination. A parallel MAC-CM with independent subchannels is first studied. The secrecy capacity region of the parallel MAC-CM is established, which gives the secrecy capacity region of the parallel MAC-CM with degraded subchannels. Next, the secrecy capacity region is established for the parallel Gaussian MAC-CM, which is used to study the fading MAC-CM. By assuming both users know the CSI, users can dynamically change their transmission power with the channel realization to achieve the best performance.
CONSTRAINED JOB MATCHING: DOES TEACHER JOB SEARCH HARM DISADVANTAGED URBAN SCHOOLS?

Search theory suggests that early career job changes lead to better matches that benefit both workers and firms, but this may not hold in teacher labor markets characterized by salary rigidities, barriers to entry, and substantial differences in working conditions. Of particular concern to education policy makers is the possibility that teacher turnover adversely affects the quality of instruction in schools serving predominantly disadvantaged children. Although such schools experience higher turnover on average than others, the impact on the quality of instruction depends crucially on whether it is the more productive teachers who are more likely to depart. The absence of direct measures of productivity typically hinders efforts to measure the effect of turnover on worker quality. In the case of teachers, however, the availability of matched panel data of students and teachers enables the isolation of the contributions of teachers to achievement. The empirical analysis reveals that teachers who remain in their school tend to outperform those who leave, particularly those who exit the Texas public schools entirely. Moreover, this gap appears to be larger for schools serving predominantly low income students, evidence that high turnover is not nearly as damaging as many suggest.
A Brief Summary of L. van Wijngaarden's Work Up Till His Retirement

This paper attempts to provide an overview of Professor Leen van Wijngaarden's scientific work by briefly summarizing a number of his papers. The review is organized by topic and covers his work on pressure waves in bubbly liquids, bubble dynamics, two-phase flow, standing waves in resonant systems, and flow cavitation noise. A list of publications up till his retirement in March 1997 is provided in the Appendix.
A Quintic Spline Interpolator for Motion Command Generation of Computer-Controlled Machines

This paper presents a new method of motion command generation for computer controlled multi-axis machines. The method is based on a quintic spline interpolator (QSI) which generates motion commands to trace a set of desired discrete position data via a composite quintic spline (CQS). This CQS is nearly arc length parametrized and has second order continuous at the data points. Consequently, the generated motion trajectories are continuous in both velocity and acceleration throughout the motion. A quick motion command generation scheme is also developed. Compared to the existing linear interpolator (LI), the proposed method takes comparable execution time, but is superior in many other aspects, including position accuracy, speed smoothness, acceleration continuity, torque requirement, and jerk reduction. Compared to the existing cubic spline interpolator (CSI), the proposed method is able to maintain a similarly smooth composite profile, but better speed accuracy. On-line implementation of this interpolator is believed very promising.