cssi/SciSciGPT-SciSciNet huggingface dataset:
Models and Their Uses

It is argued that economists ought to recognize that modeling in different styles will be appropriate for different purposes or different stages in the development of an area of economics. As an example, the paper displays simulations of a stochastic general equilibrium model which shed light on the interpretation of widely discussed small macroeconomic vector autoregressive models connecting monetary variables to output and prices.(This abstract was borrowed from another version of this item.)
Gauss-Lucas theorems for entire functions on CM

A Gauss-Lucas theorem is proved for multivariate entire functions, using a natural notion of separate convexity to obtain sharp results. Previous work in this area is mostly restricted to univariate entire functions (of genus no greater than one unless “realness” assumptions are made). The present work applies to multivariate entire functions whose sections can be written as a monomial times a canonical product of arbitrary genus. A connection is made with the Levy-Steinitz theorem for conditionally convergent vector series, a result generalizing Riemann’s well-known theorem for conditionally convergent real number series.
A Theory of Voting Equilibria.

A voting equilibrium arises when the voters in an electorate, acting in accordance with both their preferences for the candidates and their perceptions of the relative chances of various pairs of candidates being in contention for victory, generate an election result that justifies their perceptions. Voting equilibria always exist, and the set of equilibria can vary substantially with the choice of voting system. We compare equilibria under the plurality rule, approval voting, and the Borda system. We consider a candidate-positioning game and find that the plurality rule imposes little restriction on the position of the winning candidate in three-candidate races, while approval voting leads to a winner positioned at the median of the voter distribution. We contrast campaign activities intended to influence voter preferences with activities meant to influence only perceptions of candidate viability.
Cholesteric Phase in Virus Suspensions

We report measurements of the cholesteric pitch and twist elastic constant (K22) in monodisperse suspensions of the rodlike virus filamentous bacteriophage fd. Measurements were taken for concentrations spanning the entire cholesteric region at several ionic strengths and temperatures. In the limit of high ionic strength the cholesteric pitch (P0) scales with concentration (c) as P0 ∝ c-1.66. As the ionic strength decreases, the scaling exponent systematically changes to lower values.
Dynamic stability of a rectangular plate with four free edges subjected to a follower force

One of the four free edges of the plate is subjected to a tangential follower force. The flutter load and divergence load are obtained for various slenderness ratios of the rectangular plate by means of modal analysis. In the calculation, many weak instabilities were found
Thin position for knots in a 3-manifold

We extend the notion of a thin position of a link in a 3-manifold with respect to a generalized Heegaard splitting introduced in Hayashi and Shimokawa (Pacific J. Math. 197 (2001) 301�324), to take into consideration not only compressing disks but also cut-disks for the Heegaard surfaces. We prove that, if P is a c-weakly reducible bridge surface for a link K contained in a closed, orientable, irreducible 3-manifold M, then one of the following is satisfied: � P is stabilized; � P is meridionally stabilized; � P is perturbed; � a component of K is removable; � M contains an essential meridional surface.
The Preoperative Bleeding Time Test Lacks Clinical Benefit. College of American Pathologists' and American Society of Clinical Pathologists' Position Article

The major conclusions of this position article are as follows: (1) In the absence of a history of a bleeding disorder, the bleeding time is not a useful predictor of the risk of hemorrhage associated with surgical procedures. (2) A normal bleeding time does not exclude the possibility of excessive hemorrhage associated with invasive procedures. (3) The bleeding time cannot be used to reliably identify patients who may have recently ingested aspirin or nonsteroidal anti-inflammatory agents or those who have a platelet defect attributable to these drugs. The best preoperative screen to predict bleeding continues to be a carefully conducted clinical history that includes family and previous dental, obstetric, surgical, traumatic injury, transfusion, and drug histories. A history suggesting a possible bleeding disorder may require further evaluation; such an evaluation may include performance of the bleeding time test, as well as a determination of the platelet count, the prothrombin time, and the activated partial thromboplastin time. In the absence of a history of excessive bleeding, the bleeding time fails as a screening test and is, therefore, not indicated as a routine preoperative test.
Hard Determinism, Humeanism, and Virtue Ethics

Hard determinists hold that we never have alternative possibilities of action—that we only can do what we actually do. This means that if hard determinists accept the “ought implies can” principle, they must accept that it is never the case that we ought to do anything we do not do. In other words, they must reject the view that there can be “ought”-based moral reasons to do things we do not do. Hard determinists who wish to accommodate moral reasons to do things we do not do can instead appeal to Humean moral reasons that are based on desires to be virtuous. Moral reasons grounded on desires to be virtuous do not depend on our being able to act on those reasons in the way that “ought”-based moral reasons do.
Comparison of Two Adaptive Methods for Time Delay Estimation

Two adaptive algorithms for estimating the time delay between two-sensor outputs are compared. These methods are similar in that they employ the least mean square (LMS) gradient approach to estimate the time difference of arrival to two sensors. However, they involve the LMS gradient method in different ways, and thus have different properties. Some theoretical aspects are addressed. Also, they are compared via computer simulations for a variety of cases, including time-varying delay functions corresponding to moving source or receivers.
Finite extension of polymers in turbulent flow

Abstract The statistics of polymers advected by a turbulent flow are investigated. To limit the polymer lengths above to coil–stretch transition, a FENE-P type relaxation law is used. The turbulence is modeled by a random strain, delta-correlated in time and with Gaussian statistics. The distribution of polymer lengths for both the coiled and stretched states are derived, from which are obtained analytical expressions for the moments of the distribution. The polymer stress on the fluid decreases linearly with the inverse of the Deborah number. The degradation (breaking) of the polymers is also discussed, showing that even for large Deborah number some polymers can remain unbroken.
Viable models with non-universal gaugino mediated supersymmetry breaking

Recently, extra dimensional SUSY GUT models have been proposed in which compactification of the extra dimension(s) leads to a breakdown of the gauge symmetry and/or supersymmetry. We examine a particular class of higher-dimensional models exhibiting supersymmetry and SU(5) or SO(10) GUT symmetry. SUSY breaking occurs on a hidden brane, and is communicated to the visible brane via gaugino mediation. Non-universal gaugino masses are developed at the compactification scale as a consequence of a restricted gauge symmetry on the hidden brane. In this case, the compactification scale is at or slightly below the GUT scale. We examine the parameter space of such models where gaugino masses are related due to a Pati-Salam symmetry on the hidden brane. We find limited but significant regions of model parameter space where a viable spectra of SUSY matter is generated. Our results are extended to the more general case of three independent gaugino masses; here we find that large parameter space regions open up for large values of the U(1) gaugino mass M1. We also find the relic density of neutralinos for these models to be generally below expectations from cosmological observations, thus leaving room for hidden sector states to make up the bulk of cold dark matter. Finally, we evaluate the branching fraction BF(b→sγ) and muon anomalous magnetic moment aμ.
Estimating genome-wide copy number using allele-specific mixture models

Genomic changes such as copy number alterations are one of the major underlying causes of human phenotypic variation among normal and disease subjects. Array comparative genomic hybridization (CGH) technology was developed to detect copy number changes in a high-throughput fashion. However, this technology provides only a >30-kb resolution, which limits the ability to detect copy number alterations spanning small regions. Higher resolution technologies such as single nucleotide polymorphism (SNP) microarrays allow detection of copy number alterations at least as small as several thousand base pairs. Unfortunately, strong probe effects and variation introduced by sample preparation procedures have made single-point copy number estimates too imprecise to be useful. Various groups have proposed statistical procedures that pool data from neighboring locations to successfully improve precision. However, these procedure need to average across relatively large regions to work effectively, thus greatly reducing resolution. Recently, regression-type models that account for probe effects have been proposed and appear to improve accuracy as well as precision. In this paper, we propose a mixture model solution, specifically designed for single-point estimation, that provides various advantages over the existing methodology. We use a 314-sample database, to motivate and fit models for the conditional distribution of the observed intensities given allele-specific copy number. We can then compute posterior probabilities that provide a useful prediction rule as well as a confidence measure for each call. Software to implement this procedure will be available in the Bioconductor oligo package (www.bioconductor.org).
Search for MSSM Higgses at the Tevatron

We present an overview of searches for MSSM Higgs at the Tevatron, concentrating on searches probing the high tan {beta} region. We discuss the search for A/H {yields} {tau}{tau} which is soon to be completed in the Run I data and review the new tau triggers implemented by CDF and D0 in Run II, which will greatly impact this analysis. We also present the results of a Run I search for A/Hbb {yields} bbbb performed by CDF and highlight expected improvements in this channel by both experiments in Run II.
Pole/zero cancellations in flexible space structures

A practical objective in the control of flexible space structures is to minimize the effects of vibrational dynamics at certain specified points on a structure. State feedback can be used to address this question by creating closed-loop modes which are unobservable at these points, and so do not contribute to the measured response. In the frequency domain, such modes correspond to pole/zero cancellations in the closed loop system. This paper analyzes the problem of pole/zero cancellation in flexible structures, making full use of the second-order form of such systems. An explicit expression is derived for the unique state feedback gain with minimum norm which cancels all open-loop zeros. Furthermore, the properties of the residual poles that remain observable in the closed-loop system are studied, and their stability proven for the case of colocated sensors and actuators.
Influence of diagnostic criteria on the incidence of gestational diabetes and perinatal morbidity

Objective. —To determine the incidence of gestational diabetes and its associated maternal and infant morbidity by two sets of 3-hour glucose tolerance test criteria, those recommended by the National Diabetes Data Group or the lower, modified criteria of Carpenter and Coustan. Design. —Prospective, observational outcome cohort study. Setting. —Prepaid health maintenance organization. Subjects. —A total of 2019 pregnant women preregistered in a health maintenance organization were screened for a plasma glucose of 7.77 mmol/L (140 mg/ dL) or greater, 1 hour after ingestion of a 50-g glucose drink administered after an overnight fast. Positive subjects received a 3-hour glucose tolerance test interpreted by the two criteria. Data are presented for 521 randomly selected negative screenees; 264 positive screen, negative glucose tolerance test subjects; and 101 subjects with gestational diabetes mellitus. Outcome Measures. —Maternal risk factors for diabetes, infant birth weight corrected for gestational age (birth-weight ratio), umbilical cord serum insulin levels, and 33 maternal and infant perinatal morbidities assessed from chart review. Results. —Gestational diabetes incidence was 5.0% overall based on the modified criteria and 3.2% by the recommended criteria. Maternal age and family history of diabetes were higher in both modified and recommended groups. Birth-weight ratio was 1.05 in negative screenees, 1.09 in gestational diabetes overall ( P P P Conclusions. —Fifty percent more cases of gestational diabetes were identified using the more inclusive, modified criteria. These cases had as much excess in maternal diabetes risk factors, infant macrosomia, and cord hyperinsulinemia and nearly as much increase in perinatal morbidity as subjects diagnosed by the recommended criteria. The incidence and perinatal impact of gestational diabetes may be greater than previously appreciated. The modified criteria deserve wider verification and use. ( JAMA . 1993;269:609-615)
Daily to Decadal Sea Surface Temperature Variability Driven by State-Dependent Stochastic Heat Fluxes

Abstract The classic Frankignoul–Hasselmann hypothesis for sea surface temperature (SST) variability of an oceanic mixed layer assumes that the surface heat flux can be simply parameterized as noise induced by atmospheric variability plus a linear temperature relaxation rate. It is suggested here, however, that rapid fluctuations in this rate, as might be expected, for example, from gustiness of the sea surface winds, are large enough that they cannot be ignored. Such fluctuations cannot be fully modeled by noise that is independent of the state of the SST anomaly itself. Rather, they require the inclusion of a state-dependent (i.e., multiplicative) noise term, which can be expected to affect both persistence and the relative occurrence of high-amplitude anomalies. As a test of this hypothesis, daily observations at several Ocean Weather Stations (OWSs) are examined. Significant skewness and kurtosis of the distributions of SST anomalies is found, which is shown to be consistent with a multiplicative nois...
Gravitational Lensing Characteristics of the Transparent Sun

The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent standard solar model (SSM) data. The Sun's minimum focal length is computed to a refined accuracy of 23.5 ± 0.1 AU, just beyond the orbit of Uranus. The Sun creates a single image of a distant point source visible to observers inside this minimum focal length and to observers sufficiently removed from the line connecting the source through the Sun's center. Regions of space are mapped where three images of a distant point source are created, along with their associated magnifications. Solar caustics, critical curves, and Einstein rings are computed and discussed. Extremely high gravitational lens magnifications exist for observers situated so that an angularly small, unlensed source appears near a three-image caustic. Types of radiation that might undergo significant solar lens magnifications, as they can traverse the core of the Sun, including neutrinos and gravitational radiation, are discussed.
Efficient parallel graph algorithms based on open ear decomposition

Abstract We present a parallel algorithm for a novel problem in a graph's open ear decomposition. The algorithm runs in O(log n) time with n processors on a CREW PRAM, where n is the number of vertices and m is the number of edges in the graph. We apply this result in parallel algorithms to solve the two vertex disjoint s-t paths problem in O(log n) time with n + m processors and the maximal path problem in planar graphs in O(log2 n) time with O(n) processors. Both of these algorithms run on the CRCW PRAM.
An automated audiovisual treatment of phobias administered by non-professionals

Abstract This study describes the combination of desensitization, modeling and positive reinforcement in a totally automated audiovisual program designed for use by non-professionals to treat flight phobics. Of 51 subjects who completed the program, 40 were able to fly after treatment. Also, significant positive change was noted on the Taylor Manifest Anxiety Scale for those subjects who overcome their fear of flying.
Efficiency of graphical perception

The term graphical perception refers to the part played by visual perception in analyzing graphs. Computer graphics have stimulated interest in the perceptual pros and cons of different formats for displaying data. One way of evaluating the effectiveness of a display is to measure the efficiency (as defined by signal-detection theory) with which an observer extracts information from the graph. We measured observers' efficiencies in detecting differences in the means or variances of pairs of data sets sampled from Gaussian distributions. Sample size ranged from 1 to 20 for viewing times of 0.3 or 1 sec. The samples were displayed in three formats: numerical tables, scatterplots, and luminance-coded displays. Efficiency was highest for the scatterplots (approximately equal to 60% for both means and variances) and was only weakly dependent on sample size and exposure time. The pattern of results suggests parallel perceptual computation in which a constant proportion of the available information is used. Efficiency was lowest for the numerical tables and depended more strongly on sample size and viewing time. The results suggest serial processing in which a fixed amount of the available information is processed in a given time.
Gulf-Stream-Based, Ocean-Thermal Power Plants

This paper presents the results of an ongoing analytical study at the Univ. of Mass, for the design of major components and a total power system for Gulf-Stream-based ocean-thermal power of 400 Megawatts electrical net power output. On the basis of these studies, the ultimate power potential of a 15 mile wide by 550 miles long length of the Gulf-Stream extending from south of Miami, Fla. to Charleston, S.C. is estimated to be approximately 2 trillion kilowatt hours per year which could be transmitted to shore by undersea cables. Critical subsystems and components (such as heat exchangers, ocean-based hulls, and cold water inlet pipe) are identified, and the technical basis for their configuration and design is discussed. 90/10 copper-nickel alloy plate-fin heat exchangers, with propane flowing upward (evaporators) or downward (condensers) through small passages in the plates and sea water flowing horizontally between the plates, have been selected. The latest power system (Mark II) is based on a submerged, twin catamaran concrete hull configuration with hulls approximately 80 ft in diameter by 800 ft long. The evaporators are staggered serially in height in 6 tiers placed above the twin hulls which contain the condensers, turbines, pump, and other power cycle components. A cold-water inlet pipe of elliptical cross section (1500 ft long and with a hydraulic diameter of 87 ft) is hinged between the hulls with a gun-buckler type joint. Technical problems facing the deployment of such plants are summarized, and the latest cost estimates predict busbar power costs of approximately 15 mills per kilowatt hour.
Are risk preferences stable? Comparing an experimental measure with a validated survey-based measure.

We examine the stability of risk preference within subjects by comparing measures obtained from two elicitation methods, an economics experiment with real monetary rewards and a survey with questions on hypothetical gambles. The survey questions have been validated by numerous empirical studies of investment, insurance demand, smoking and alcohol use, and recent studies have shown the experimental measure is associated with several real-world risky behaviors. For the majority of subjects, we find that risk preferences are not stable across elicitation methods. In interval regression models subjects’ risk preference classifications from survey questions on job-based gambles are not associated with risk preference estimates from the experiment. However, we find that risk classifications from inheritance-based gambles are significantly associated with the experimental measure. We identify some subjects for whom risk preference estimates are more strongly correlated across elicitation methods, suggesting that unobserved subject traits like comprehension or effort influence risk preference stability.
Sublinear time width-bounded separators and their application to the protein side-chain packing problem

Given d>2 and a set of n grid points Q in ℜ d , we design a randomized algorithm that finds a w-wide separator, which is determined by a hyper-plane, in $O(n^{2\over d}\log n)$ sublinear time such that Q has at most $({d\over d+1}+o(1))n$ points on either side of the hyper-plane, and at most $c_{d}wn^{d-1\over d}$ points within $\frac{w}{2}$ distance to the hyper-plane, where c d is a constant for fixed d. In particular, c 3=1.209. To our best knowledge, this is the first sublinear time algorithm for finding geometric separators. Our 3D separator is applied to derive an algorithm for the protein side-chain packing problem, which improves and simplifies the previous algorithm of Xu (Research in computational molecular biology, 9th annual international conference, pp. 408–422, 2005).
Second-order perturbation theory for Fabry–Perot resonators

A variant of Rayleigh-Schrodinger peturbation theory is applied to the computation of the additional power losses and phase shifts caused by perturbations of optical resonators. Numerical results are given for tilted infinite-strip plane resonators. For a large range of Fresnel numbers and sufficiently small angles of tilt, there is good agreement between these and previous results. The major advantages of this technique are its applicability for both high Fresnel numbers and higher-order modes with only a minimal use of computer time.
Novel hypoglycemic dihydropyridones serendipitously discovered from O- versus C-alkylation in the synthesis of VMAT2 antagonists

Vesicular monoamine transporter type 2 (VMAT2) is a newly emerging target for both diagnostic and therapeutic applications in diabetes mellitus. In pursuit of novel VMAT2 antagonists, we identified a potent hypoglycemic agent with a novel dihydropyridone scaffold. Several analogs were designed and synthesized. A preliminary structure activity relationship (SAR) showed that the dihydropyridone scaffold is required for the activity.
Magnetic Flux Cancellation and Coronal Magnetic Energy

I investigate the processes at work in the cancellation of normal magnetic flux in solar magnetograms and study the relationships between cancellation and the budget of free magnetic energy in the coronal magnetic field that can power solar flares and CMEs. After defining cancellation mathematically, I derive equations that quantify the evolution of free magnetic energy in response to arbitrary plasma flows on the boundary, including flows consistent with cancellation. While cancellation can reduce the magnetic energy in both the actual coronal field and the potential field matching the same normal field boundary condition, cancellation can, in the process, increase the difference between the two; i.e., cancellation can increase the free magnetic energy in the corona. By making simple assumptions based upon typical observed field configurations in filament channels, I show that cancellation tends to add free energy to these fields. Finally, I discuss the implications of this fact, as well as wider applications of the free energy flux formalism developed here. I also briefly address related issues, including the relationship of cancellation to Taylor's hypothesis.
A Novel Abundance-Based Algorithm for Binning Metagenomic Sequences Using l-tuples

Metagenomics is the study of microbial communities sampled directly from their natural environment, without prior culturing. Among the computational tools recently developed for metagenomic sequence analysis, binning tools attempt to classify the sequences in a metagenomic dataset into different bins (i.e., species), based on various DNA composition patterns (e.g., the tetramer frequencies) of various genomes. Composition-based binning methods, however, cannot be used to classify very short fragments, because of the substantial variation of DNA composition patterns within a single genome. We developed a novel approach (AbundanceBin) for metagenomics binning by utilizing the different abundances of species living in the same environment. AbundanceBin is an application of the Lander-Waterman model to metagenomics, which is based on the l-tuple content of the reads. AbundanceBin achieved accurate, unsupervised, clustering of metagenomic sequences into different bins, such that the reads classified in a bin belong to species of identical or very similar abundances in the sample. In addition, AbundanceBin gave accurate estimations of species abundances, as well as their genome sizes-two important parameters for characterizing a microbial community. We also show that AbundanceBin performed well when the sequence lengths are very short (e.g., 75 bp) or have sequencing errors. By combining AbundanceBin and a composition-based method (MetaCluster), we can achieve even higher binning accuracy. Supplementary Material is available at www.liebertonline.com/cmb .
Solid Solution Studies of Layered Honeycomb-Ordered Phases O3-Na3M2SbO6 (M = Cu, Mg, Ni, Zn)

Complete solid solutions with the composition Na₃M2–xM´xSbO₆ where M, M´=Cu, Mg, Ni, Zn have been synthesized by conventional solid state techniques and were investigated using X-ray diffraction, magnetic susceptibility and optical measurements. All compositions crystallize in a monoclinic unit cell and exhibit a layered structure with a honeycomb cationic ordering within the slabs. These compounds also exhibit Curie–Weiss behavior at high temperature and the magnetic moment values verify the presence of Cu²⁺ and/or Ni²⁺. The antiferromagnetic order of Na₃Ni₂SbO₆ is suppressed upon substitution of Ni²⁺ with Mg²⁺ or Zn²⁺. The spin gap observed in Na₃Cu₂SbO₆ is also suppressed by substitution of Cu²⁺ with Mg²⁺ or Zn²⁺. The Na₃Ni2–xCuxSbO₆ compositions follow an expected transition from an antiferromagnetic ordering to the spin gap of the copper end member. The estimated band gaps for these compounds have been determined from diffuse reflectance measurements. - Graphical abstract: Complete solid solutions with the composition Na₃M2–xM´xSbO₆ where M, M´=Cu, Mg, Ni, Zn have been synthesized using conventional solid state techniques and were investigated using X-ray diffraction, magnetism and optical measurements. Based on an ionic radii point of view the lattice parameter shifting in the composition containing copper are opposite of what would be expected. The Cu²⁺more » is Jahn–Teller active which distorts the C2/m cell, increasing the β angle between the a and c parameters and explains this shifting pattern. Highlights: • The solid solutions O₃–Na₃M2–xM´xSbO₆(M, M´=Cu, Mg, Ni, Zn) were synthesized. • These compounds crystallize in the C2/m space group. • The Jahn–Teller active Cu²⁺ causes distortion of the monoclinic cell. • The Cu²⁺ spin gap magnetic properties are diluted upon 25% substitution. • All compositions are insulating and have large band gaps.« less
Partisan mobilization, cognitive mobilization and the changing American electorate

Abstract The concept of party identification is central to our understanding of American electoral behavior. This research builds upon the functional logic of party identification and asks what occurs if citizens become better able to manage the complexities of politics without relying on habitual party cues. Using the data from the American National Election Studies, we track the distribution of party mobilization and cognitive mobilization within the American electorate. Then, we demonstrate the importance of these alternative mobilization patterns by documenting strong differences in the content of political thinking, voting choice, and electoral change. The results suggest a secular transformation in the characteristics of the American public since the classic images of The American Voter, leading to a more differentiated and dealigned electorate.
Accelerated filament formation from tau protein with specific FTDP-17 missense mutations

Tau is the major component of the neurofibrillar tangles that are a pathological hallmark of Alzheimers' disease. The identification of missense and splicing mutations in tau associated with the inherited frontotemporal dementia and Parkinsonism linked to chromosome 17 demonstrated that tau dysfunction can cause neurodegeneration. However, the mechanism by which tau dysfunction leads to neurodegeneration remains uncertain. Here, we present evidence that frontotemporal dementia and Parkinsonism linked to chromosome 17 missense mutations, P301L, V337M and R406W, cause an accelerated aggregation of tau into filaments. These results suggest one mechanism by which these mutations can cause neurodegeneration and frontotemporal dementia and Parkinsonism linked to chromosome 17.
Volumes of Picard modular surfaces

We show that the conjectural cusped complex hyperbolic 2-orbifolds of minimal volume are the two smallest arithmetic complex hyperbolic 2orbifolds. We then show that every arithmetic cusped complex hyperbolic 2-manifold of minimal volume covers one of these two orbifolds. We also give all minimal volume manifolds that simultaneously cover both minimal orbifolds.
The effect of chlorine on hydrogen chemisorption by silica-supported Ru catalysts: A proton NMR study

Silica-supported ruthenium catalysts prepared from the RuCl3 · 3H2O precursor contain residual chloride after reduction in flowing hydrogen. The amount of this chlorine was determined by X-ray fluorescence spectroscopy to be less than one monolayer on the ruthenium surfaces. Both volumetric hydrogen chemisorption and proton NMR show suppression of hydrogen chemisorption capacity associated with the presence of chlorine contamination, which can be removed effectively with hot water elution. The variations of the hydrogen chemisorption capacity with chlorine coverage suggests that chlorine would completely block and poison the Ru surfaces for hydrogen chemisorption at a Cl coverage of about 76%. The effect of residual chloride on the proton NMR resonance position and the spin-lattice relaxation time for the chemisorbed hydrogen indicates an electronic interaction between Cl adspecies and surface Ru, which results in the weakening of the H-Rus chemisorptive bond at the Ru surfaces. This reduced H-Rus interaction may be the cause for an increase in the ratio of the reversibly adsorbed hydrogen over the irreversibly adsorbed hydrogen with increasing Cl coverage. It is proposed that the mechanism for suppression of hydrogen chemisorption by chlorine involves both physical site blocking of surface Ru atoms and shortranged electronic interactions between Cl adatoms and neighboring surface Ru atoms.
Three-Dimensional Heat-Transfer and Ablation Disturbances in High-Speed Flows

A unified theory of steady-state disturbances in compressible laminar or turbulent boundary-layers and their interaction with the adjacent surface material is developed on the basis of a small perturbation approach. Fourier transformation is used to treat both periodic and nonperiodic disturbances within a common framework. The important effect of the highly nonuniform flow across the boundary-layer is taken into account, as are the effects of surface heat and mass transfer, lateral pressure gradient, and upstream influenc in the disturbance field. Three illustrative applications to the prediction of pressure, skin-friction, and heat-transfer disturbances are given including comparisons with experiment: the boundary-layer along a wavy structural skin with heat transfer, ablation surface cross-hatching, and flow past a rear-facing step or suction gap.
Properties of serial kanban systems

In this paper we show some structural results of a kanban system by using results about the underlying GSMP. The main results from this connection are: dominance of allocations, optimal partition, upper and lower bounds on throughput, consistency of the IPA derivative, convexity of throughput as a function of service time parameters and concavity of throughput with respect to number of kanbans. Although the dominance and the partition results were obtained previously by sample path arguments, the proofs here are less cumbersome and generalize the earlier results. The second-order properties for kanban lines are new. These results form a basis for results in multi-product lines where proofs by sample paths require extensive notation.
Investigation of Tip Clearance Phenomena in an Axial Compressor Cascade Using Euler and Navier–Stokes Procedures

Three-dimensional Euler and full Navier-Stokes computational procedures have been utilized to simulate the flow field in an axial compressor cascade with tip clearance. An embedded H-grid topology was utilized to resolve the flow physics in the tip gap region. The numerical procedure employed is a finite difference Runge-Kutta scheme. Available measurements of blade static pressure distributions along the blade span, dynamic pressure and flow angle in the cascade outlet region, and spanwise distributions of blade normal force coefficient and circumferentially averaged flow angle are used for comparison. Several parameters that were varied in the experimental investigations were also varied in the computational studies
Post-Doha Trade Policy Options for a Small Country:

This paper uses a partial equilibrium model of two small countries, within a large world economy, implementing reciprocal tariff cuts on each other’s exports in a regional trade agreement (RTA) and compares the effects with unilateral most favoured nation (MFN) tariff cuts. The reciprocal cuts are shown to be more likely beneficial to a country if the partner country’s trade is larger. The welfare effects of a country’s own tariff cut on imports are also compared to the effects on its welfare of the partner country’s tariff cut on its exports. If tariff levels are low, the latter is seen to be larger than the former. Implications of the analysis are that, if multilateral trade liberalisation is unlikely, then small countries should seek to form RTAs with countries larger than themselves. In addition, to assure that they have something to offer in such arrangements, they should not go too far in unilaterally reducing their MFN tariffs.
Three Spheres of Classification Research: Emergence, Encyclopedism, and Ecology

Three paths of interdisciplinary work shape the future of classification research. They are emergence, encyclopedism, and ecology. Each of these, in method, approach, and in substantive inquiry outline both the boundaries and the intersections of the many fields that contribute to our overall understanding of classification research. This paper outlines some high level claims of this work, ties it to current research and offers some theoretical applications of these paths.
Unique continuation for the Schrödinger equation with gradient vector potentials

We obtain unique continuation results for Schrodinger equations with time dependent gradient vector potentials. This result with an appropriate modification also yields unique continuation properties for solutions of certain nonlinear Schrodinger equations.
The optimal order for the p-th moment of sums of independent random variables with respect to symmetric norms and related combinatorial estimates

For n independent random variables f1, . . . ,fn and a symmetric norm || ||X on ℝn, we show that for 1≤ p < ∞
Flow Patterns Near a Conical Sonic Line

A study is made in the physical plane of the flow properties near a conical cross flow sonic line. The shapes of the Mach lines at regular and singular sonic points are presented. Through a study of the jump conditions at a singular sonic point, the possibility of a double sonic line is discussed. The properties of bubbles of supersonic cross flow are examined. Numerical results are presented to support some of the theoretical observations.
A new distributed topology control algorithm for wireless environments with non-uniform path loss and multipath propagation

Each node in a wireless multi-hop network can adjust the power level at which it transmits and thus change the topology of the network to save energy by choosing the neighbors with which it directly communicates. Many previous algorithms for distributed topology control have assumed an ability at each node to deduce some location-based information such as the direction and the distance of its neighbor nodes with respect to itself. Such a deduction of location-based information, however, cannot be relied upon in real environments where the path loss exponents vary greatly leading to significant errors in distance estimates. Also, multipath effects may result in different signal paths with different loss characteristics, and none of these paths may be line-of-sight, making it difficult to estimate the direction of a neighboring node. In this paper, we present Step Topology Control (STC), a simple distributed topology control algorithm which reduces energy consumption while preserving the connectivity of a heterogeneous sensor network without use of any location-based information. The STC algorithm avoids the use of GPS devices and also makes no assumptions about the distance and direction between neighboring nodes. We show that the STC algorithm achieves the same or better order of communication and computational complexity when compared to other known algorithms that also preserve connectivity without the use of location-based information. We also present a detailed simulation-based comparative analysis of the energy savings and interference reduction achieved by the algorithms. The results show that, in spite of not incurring a higher communication or computational complexity, the STC algorithm performs better than other algorithms in uniform wireless environments and especially better when path loss characteristics are non-uniform.
Thin-source concentration-dependent diffusion: A full solution.

A new method of analysis is developed for solving the problem of an initially thin source of impurity ions diffusing into a host solid when the mechanism of transport involves a concentration-dependent diffusivity. In order to extract a diffusivity from experimental data we show that the fundamental experiment required is a measurement of the diffusion profile at two different times. The constant and the concentration-dependent contributions to the diffusivity then can be isolated by requiring the initial measured profile to propagate into the final measured profile. The analytic procedure presented here is shown to be a full solution to the problem of a diffusivity that varies linearly with concentration: D(C)=${D}_{0}$(1+\ensuremath{\alpha}C), where \ensuremath{\alpha} is the strength of the nonlinear term. A matrix of orthogonal functions determines the time evolution for an arbitrary thin-source initial state. We show that the total diffusant amount is conserved and that the solution is naturally expressed as a power series in \ensuremath{\alpha}. The persistence of curvature on ln(C)-vs-${x}^{2}$ axes is then derived from the asymptotic (long-time) properties of the nonlinear equation solution. The solution up through order ${\ensuremath{\alpha}}^{2}$ is then explicitly constructed for an arbitrary thin-source initial state.
PMPS: A Prototype CAPP System for Parallel Machining

Parallel N.C. machines, also referred to as mill-turns, are a new generation of machine tools aimed at increasing machining accuracy and reducing part cycle times. In addition to their capacity to do both milling and turning, these next generation machines tools can perform multiple machining operations simultaneously, involving one or more parts at a time, and can completely finish a part (front and back) in a single setup. Parallel machining raises issues with respect to computer aided process planning which have not been dealt with in the past. In this paper, a prototype CAPP system called PMPS, for parallel machining, is described. First, we briefly highlight the new issues to be dealt with in process planning for parallel machining. Next, the architecture and details of PMPS, a generative CAPP system, is described. Finally, the implementation and results are discussed.
Approximation algorithms for the capacitated minimum spanning tree problem and its variants in network design

Given an undirected graph G = (V,E) with nonnegative costs on its edges, a root node rV, a set of demands DV with demand vD wishing to route w(v) units of flow (weight) to r, and a positive number k, the Capacitated Minimum Steiner Tree (CMStT) problem asks for a minimum Steiner tree, rooted at r, spanning the vertices in D * lrr, in which the sum of the vertex weights in every subtree connected to r is at most k. When D e V, this problem is known as the Capacitated Minimum Spanning Tree (CMST) problem. Both CMsT and CMST problems are NP-hard. In this article, we present approximation algorithms for these problems and several of their variants in network design. Our main results are the following:---We present a (³ AST + 2)-approximation algorithm for the CMStT problem, where ³ is the inverse Steiner ratio, and AST is the best achievable approximation ratio for the Steiner tree problem. Our ratio improves the current best ratio of 2AST + 2 for this problem.---In particular, we obtain (³ + 2)-approximation ratio for the CMST problem, which is an improvement over the current best ratio of 4 for this problem. For points in Euclidean and rectilinear planes, our result translates into ratios of 3.1548 and 3.5, respectively.---For instances in the plane, under the Lp norm, with the vertices in D having uniform weights, we present a nontrivial (7/5AST + 3/2)-approximation algorithm for the CMStT problem. This translates into a ratio of 2.9 for the CMST problem with uniform vertex weights in the Lpmetric plane. Our ratio of 2.9 solves the long-standing open problem of obtaining any ratio better than 3 for this case.---For the CMST problem, we show how to obtain a 2-approximation for graphs in metric spaces with unit vertex weights and k = 3,4.---For the budgeted CMST problem, in which the weights of the subtrees connected to r could be up to ± k instead of k (± e 1), we obtain a ratio of ³ p 2/±.
Service Referral Patterns Among Black and White Families Involved With Child Protective Services

Racial disproportionality in child protective services is widely studied, yet the role of race in caseworkers' service referral decisions remains less understood. Using the National Survey of Child and Adolescent Well-Being II, multiple regression models and Blinder-Oaxaca decompositions assess whether the intersection of caseworker and child race predicts differences in service referral decisions, and whether service disparities were primarily explained by racial differences in case characteristics or by differential treatment of families. While many raw differences in service referrals were explained by case characteristics, unexplained differences were found in the types of services to which families were referred.
Possible relevance of odd frequency pairing to heavy fermion superconductivity

Abstract What is the character of the gapless quasiparticles in heavy fermion superconductors (HFSC)? We discuss an odd-frequency pairing interpretation of HSFC which leads to a two component model for the quasiparticle excitations. In this picture, line zeroes of unpaired electrons may coexist with gapless surfaces of paired electrons, with vanishing spin and charge coherence factors.
Solving Fluid Flow Problems on Moving and Adaptive Overlapping Grids

Solution of fluid dynamics problems on overlapping grids will be discussed. An overlapping grid consists of a set of structured component grids that cover a domain and overlap where they meet. Overlapping grids provide an effective approach for developing efficient and accurate approximations for complex, possibly moving geometry. Topics to be addressed include the reactive Euler equations, the incompressible Navier-Stokes equations and elliptic equations solved with a multigrid algorithm. Recent developments coupling moving grids and adaptive mesh refinement and preliminary parallel results will also be presented.
Spin-Orbit Splittings in Nuclear Shell Model

Data (mostly from stripping reactions'') on locations of nuclear shell- model states are analyzed to determine energy splittlngs of spin-orbit doublets, and the systematics is studied. The expected (21 + 1) dependence of the splitting is roughly corroborated, but the splitting is considerably larger than is expected when the two levels are in different major shells. The mass dependence of the splitting is somewhat stronger than the expected proportionality to A/sup 1/3/. Applications to reduced mass'' questions, and to the location of unknown 1evels, are discussed. (auth)
Tether-Induced Airglow: Collisionless Effects

Martinez-Sanchez and Sanmartin [1997] showed that a bare conducting tether can be used as a source of an energetic electron beam. Interacting with the E region atmosphere, the beam should produce airglow thus making possible to deduce the neutral density on a continuous basis. Fujii et al. [2005] suggested that this idea be tested in a specially-designed sounding rocket experiment. We show that collisionless beam-plasma interactions (BPI) complement direct impact, leading to appreciable green-line (557.7 nm) emissions in the F region. In the E region, BPI develops near the entry in the valley, resulting in a narrow layer of strongly-elevated and airglow. Besides, neutralizing electric currents carried by ionospheric electrons in the valley can become unstable or even insufficient to compensate the beam current. Developing plasma waves inhibit neutralizing currents. In the extreme case, the beam might be locked in the valley (the 'virtual cathode'). In addition to optical observations, these effects can also be observed by radiophysical means.
Regioselective ribosylation of 6,7-dichloroimidazo[4,5-b]quinolin-2-one

Regioselective ribosylation conditions were established which gave both 6,7-dichloro-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)imidazo[4,5-b]quinolin-2-one (4) and 6,7-dichloro-3-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)imidazo [4,5-b]quinolin-2-one (5), respectively, in high yield from 6,7-dichloroimidazo[4,5-b]quinolin-2-one (6). The distributions of the sites of ribosylation under a variety of conditions are discussed.
Catalytic asymmetric acyl halide-aldehyde cyclocondensation reactions of substituted ketenes.

Catalytic asymmetric acyl halide−aldehyde cyclocondensation (AAC) reactions of alkyl-substituted ketenes with structurally diverse aldehydes provide cis-disubstituted β-lactones with high enantioselectivity. The AAC reactions utilize a novel Al(III)-triamine catalyst in which the metal's dynamic coordination geometry leads to a highly selective catalyst complex. These AAC reactions represent a functional solution to highly enantioselective substituted ester enolate aldol additions.