cssi/SciSciGPT-SciSciNet huggingface dataset:
Partition testing with usage models

Abstract The fundamental statistical strategy of improving sampling efficiency through partitioning the population is applied to software testing. Usage models make it possible to apply this strategy to improve the efficiency of testing. The testing budget is allocated to the blocks of the partition, and the software is executed on the sample of uses drawn from each block or sub-population of potential uses. Usage models support many strategies for automated partitioning and generating test cases from the partitioned population. Two strategies are shown here with the efficiency gains demonstrated.
Crystal growth of a new series of non-centrosymmetric oxides, Ln3FeO6 (Ln = La, Nd, Sm, Eu and Gd)

Abstract Single crystals of Ln 3 FeO 6 ( Ln = La, Nd, Sm, Eu, Gd) were grown out of a high temperature hydroxide melt. The crystal structures were determined by single crystal X-ray diffraction. These oxides crystallize in the polar space group Cmc 2 1 where the orientations of the FeO 4 tetrahedra determine the polarity of the structure. The lanthanide atoms are located in a seven-fold, square face mono-capped trigonal prismatic coordination environment; these polyhedra are edge-shared to form zig-zag chains.
Discovery of a New 89 Second X-Ray Pulsar: XTE J1906+09

We report on the discovery of a new pulsating X-ray source during Rossi X-ray Timing Explorer (RXTE) observations of a low galactic latitude field centered at R.A. (J2000) = 19h05m43s, decl. (J2000) = +08°58'48''. Significant pulsations were detected by both the Proportional Counter Array and the High Energy X-ray Timing Experiment instruments aboard RXTE at a fundamental period of 89.17 ± 0.02 s, with higher harmonics also visible in the 2-10 keV power spectrum. The folded light curve from the source is multiply peaked at lower energies and changes to a single-peaked morphology above ~20 keV. The phase-averaged spectrum from the source is well fit by strongly absorbed power-law or thermal bremsstrahlung spectral models of photon index 1.9 ± 0.1 or temperature 19.5 ± 4.6 keV, respectively. The mean neutral hydrogen column density is NH ≈ 1023 cm-2, suggesting a distance of greater than 10 kpc to the source and a minimum 2-10 keV X-ray luminosity of 2 × 1035 ergs s-1. By comparison with other pulsars with similar periods and luminosities, we suggest that XTE J1906+09 has a supergiant companion with an underfilled Roche lobe. We speculate further that one of the M stars in a peculiar M star binary system may be the companion.
Elliptic Weyl group elements and unipotent isometries with $p=2$

Let G be a classical group over an algebraically closed field of characteristic 2 and let C be an elliptic conjugacy class in the Weyl group. In a previous paper the first named author associated to C a unipotent conjugacy class \Phi(C) in G. In this paper we show that \Phi(C) can be characterized in terms of the closure relations between unipotent classes. Previously the analogous result was known in odd characteristic and for exceptional groups in any characteristic.
Copolymer crystallization: Approaching equilibrium

Abstract Melt crystallization of random copolymers leads to solids with crystalline fraction w c and final melting temperature T m f that are substantially below the predictions of Flory's equilibrium crystallization theory. Model ethylene/butene random copolymers, when crystallized as multilayer films by rapid solvent evaporation, exhibit increased w c (50% relative) and T m f (4 K) compared to melt crystallized values. For a copolymer with 0.92 mol fraction ethylene, the density-derived crystallinity w c =0.6 is the same as that from Flory's theory, although the maximum observable crystal thickness from T m f remains about 25% of the theory value. These effects are seen because crystallization from solution occurs without many of the constraints to segment dynamics that limit crystalline fraction during melt crystallization. Crystal thickness is dominated by secondary nucleation barriers in both melt and solution. Chain or sequence folding is much more regular in the solution crystallized material, and amorphous layer thickness is reduced from about 8 nm to 3 nm.
Recent developments in the study of mesospheric clouds

Abstract Understanding the physics of ice particles at the cold summertime mesopause (85 km altitude) and their atmospheric environment represent a challenge to both experimentalists and theorists. This review emphasizes recent advances, both experimental and theoretical, in understanding the unique properties of this region of the atmosphere. Evidence is presented for mean cloud particle sizes to be less than 100 nm in effective radius. Charging of cloud particles by collisional attachment of electrons may cause local electron depletions. However this process appears to explain only partly the electron ‘bite-out’ phenomenon. Nor does it appear to explain all aspects of polar mesospheric summertime radar echoes (PMSE). It is possible that the particles acquire a large positive charge as a result of the photoelectric effect. However special ad hoc coatings of the ice surfaces by low-work function metals are needed. No satisfactory theory yet exists for PMSE. Observations of mesospheric phenomena over decadal time spans reveal significant cyclical and secular changes. In particular, changes in noctilucent cloud occurrence frequency, brightness and altitude offer important clues with regard to long-term compositional changes of the middle atmosphere.
Surface-Enhanced Raman Scattering As an In-Situ Probe of Polyimide/Silver Interphases

Abstract The molecular structure of interphases formed by chemically curing the polyamic acid of pyromellitic dianhydride (PMDA) and oxydianiline (ODA) against meta-aminothiophenol (m-ATP)-primed silver substrates was determined using surface-enhanced Raman scattering (SERS) and reflection-absorption infrared spectroscopy (RAIR). It was found that m-ATP was adsorbed dissociatively onto silver substrates through the sulfur atoms. When polyamic acid was deposited onto silver substrates pretreated with m-ATP, acid groups of the polyamic acid combined with amino groups of m-ATP to form ammonium carboxylate salts near the interphase. SERS and RAIR results indicated that the structure of the interphase was significantly different from that of the bulk polymer. Chemical curing of the polyamic acids located in the interphase was suppressed because of the formation of ammonium carboxylate salts. However, the bulk of the polyamic acid films was highly cured to form polyimide. It was also found that more isoimide gr...
A Theoretical Framework Linking Creativity, Empowerment, and Organizational Memory

Empowerment, creativity, and organizational memory are constructs that have been researched in MIS. While each construct has received individual attention, we have found relatively little research linking them. One of the major edicts of empowerment is delegation of decision making authority to lower-level employees. Increased authority allows employees more freedom to be creative. However, if creative thought is generated but not captured, innovative ideas may be lost. Organizational memory can capture creative ideas as they are generated so that empowered teams can draw upon positive creative experiences. We developed a theoretical model to illuminate the relationships between organizational memory, worker empowerment, and creativity. The model portrays the linkages between empowerment and creativity, creativity and organizational memory, and organizational memory and empowerment. The model was developed based on the literature in each respective area and an interview-based study concerning “empowered” systems development project teams and organizational memory. Analysis of the interview data revealed that empowered workers generate creative solutions to problems. However, creative solutions can only be used for future projects if they are somehow recorded into organizational memory. Organizations that empowered their workforce and embraced creativity reported increased customer satisfaction, waste reduction, and some quality gains. In contrast, those that did not empower reported little or no change. Organizations that recorded creative solutions to problems believe that retrieval of this information could be potentially useful for future projects. Potential challenges faced by organizations classified into each cell are also presented. This classification scheme should prove useful as a guide to organizations examining the potential benefits and pitfalls of worker empowerment and organizational memory.
Accuracy of the Lightning Mapping Array

[1] The location accuracy of the New Mexico Tech Lightning Mapping Array (LMA) has been investigated experimentally using sounding balloon measurements, airplane tracks, and observations of distant storms. We have also developed simple geometric models for estimating the location uncertainty of sources both over and outside the network. The model results are found to be a good estimator of the observed errors and also agree with covariance estimates of the location uncertainties obtained from the least squares solution technique. Sources over the network are located with an uncertainty of 6–12 m rms in the horizontal and 20–30 m rms in the vertical. This corresponds well with the uncertainties of the arrival time measurements, determined from the distribution of chi-square values to be 40–50 ns rms. Outside the network the location uncertainties increase with distance. The geometric model shows that the range and altitude errors increase as the range squared, r2, while the azimuthal error increases linearly with r. For the 13 station, 70 km diameter network deployed during STEPS the range and height errors of distant sources were comparable to each other, while the azimuthal errors were much smaller. The difference in the range and azimuth errors causes distant storms to be elongated radially in plan views of the observations. The overall results are shown to agree well with hyperbolic formulations of time of arrival measurements [e.g., Proctor, 1971]. Two appendices describe (1) the basic operation of the LMA and the detailed manner in which its measurements are processed and (2) the effect of systematic errors on lightning observations. The latter provides an alternative explanation for the systematic height errors found by Boccippio et al. [2001] in distant storm data from the Lightning Detection and Ranging system at Kennedy Space Center.
Models as executable designs

If a design is viewed as a model of the eventual implementation, and if it is expressed in a well-defined design notation, it can be made executable and treated as a prototype which reflects whatever internal details are expressed in the design. However, to turn this technique into a way of constructing a prototype whose externally-observable behavior is meaningful from the user's point of view, methods must first be developed for the rapid prototyping of user interfaces.
Stille Couplings Catalytic in Tin: Beyond Proof-of-Principle

Stille cross-couplings1 often involve the palladium-catalyzed union of vinyl or aryl halides with vinylstannanes to form 1,3dienes. Stille reactions are quite tolerant to a large array of functionality, typically proceed with a conservation of olefin geometry, and are most often regiospecific with regards to the newly formed C-C σ-bond. As such, Stille reactions have proven useful in natural product synthesis,2 the construction of new materials,3 heterocycle preparation,4 carbohydrate chemistry,5 and support of bioorganic research.6 Furthermore, Stille couplings are quite compatible with various new technologies. They behave well in a combinatorial setting,2a,7 are rapidly accelerated under microwave irradiation,8 have proven amenable to reaction in the fluorous phase,8b,9 and offer great potential in the very nonpolar environment of supercritical carbon dioxide.10 Despite such synthetic utility, a historic drawback of the Stille reaction has been its reliance on stoichiometric quantities of toxic, costly, and occasionally unstable organostannanes.11,12 Therefore, we believe a Stille reaction, which is catalytic in tin, would be of considerable benefit.13 The invention of such a catalytic method poses several challenges. Perhaps most fundamental among these is that while many important advances in the development of catalytic versions of tin-mediated reactions have been realized,11,14 most prior efforts have focused on tin reagents such as Bu3SnH, Bu2SnO, (BuCH(Et)CO2)3SnBu, etc. Little attention has been given to the invention of catalytic variants for chemical transformations, where the organotin species is a reactant covalently bonded to the organic molecular material of interest. In short, rendering the Stille reaction catalytic in tin would require an initial molecule of organotin hydride to participate in a chemoselective sequence of in situ vinyltin generation, cross-coupling, and then a final transformation of the organotin halide byproduct back to tin hydride.
Industrial Experience on the Caustic Cracking of Stainless Steels and Nickel Alloys - A Review

Caustic environments are present in several industries, from nuclear power generation to the fabrication of alkalis and alumina. The most common material of construction is carbon steel but its application is limited to a maximum temperature of approximately 80 C. The use of Nickel (Ni) alloys is recommended at higher temperatures. Commercially pure Ni is the most resistant material for caustic applications both from the general corrosion and the stress corrosion cracking (SCC) perspectives. Nickel rich alloys also offer a good performance. The most important alloying elements are Ni and chromium (Cr). Molybdenum (Mo) is not a beneficial alloying element and it dissolves preferentially from the alloy in presence of caustic environments. Austenitic stainless steels such as type 304 and 316 seem less resistant to caustic conditions than even plain carbon steel. Experimental evidence shows that the most likely mechanism for SCC is anodic dissolution.
Some statistical characteristics of voice fundamental frequency.

Two experiments are reported in which the magnitude of sampling errors associated with estimates of the mean, median, and standard deviation of voice fundamental frequencies (fo) during oral readin...
Solar ultraviolet variability during the TIMED mission

Abstract The Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics (TIMED) satellite was launched in December 2001 near solar cycle 23 maximum. The solar activity remained at a high level during 2002 and has since declined to moderate activity. As part of the TIMED mission objective to study the energetics of the upper atmosphere, the Solar EUV Experiment (SEE) aboard TIMED measures the solar extreme ultraviolet (EUV) energy input. The SEE instrument is measuring the solar UV irradiance with a spectral resolution of 0.4 nm between 27 and 194 nm and with 7–10 nm resolution shortward of 27 nm. The solar UV irradiance varies on all time scales, seconds to years, and this variation is very dependent on wavelength. During the TIMED mission, the SEE instrument has observed over 200 flares that last from minutes to hours, over 30 solar rotations that have a period of about 27 days, and maximum to moderate conditions during the current 11-year solar cycle. The coronal emissions, such as the Fe XVI 33.5 nm emission and X-rays, vary the most, with variations of a factor of 10 for the larger flares, a factor of two for solar rotation, and a factor of four during the TIMED mission (2 years). The transition region and upper chromospheric emissions, such as the H I 121.6 nm and He II 30.4 nm emissions, vary less, with variations of a factor of 1.2 for solar rotation and a factor of 2 during the TIMED mission. The lower chromospheric and photospheric emissions vary even less. The variations of the solar UV irradiance shortward of 194 nm will be discussed in the context of the TIMED mission.
Palladium-catalyzed amination of aryl halides and sulfonates

Abstract In this review, the progress made in the palladium-catalyzed amination of aryl halides and sulfonates is described with particular attention given to applications in synthetic organic chemistry.
Rotating Wilson loops and open strings in AdS3

The AdS/CFT correspondence relates N = 4 super Yang‐Mills on S 3 to type IIB string theory on AdS5 ×S 5 . In this context, a quark/anti-quark pair moving on an S 1 ⊂ S 3 following prescribed trajectories is dual to an open string ending on the boundary of AdS3. In this paper we study the corresponding classical string solutions. The Pohlmeyer reduction reduces the equations of motion to a generalized sinh-Gordon equation. This equation includes, as particular cases, the Liouville equation as well as the sinh/cosh-Gordon equations. We study generic solutions of the Liouville equation and finite gap solutions of the sinh/cosh-Gordon ones. The latter ones are written in terms of Riemann theta functions. The corresponding string solutions are reconstructed giving new solutions and a broad understanding of open strings moving in AdS3. As a further example, the simple case of a rigidly rotating string is shown to exhibitthesethreebehaviorsdependingonasimplerelationbetweenitsangular velocity and the angular separation between its endpoints.
Religiosity and State Welfare

Abstract The Catholic sex abuse scandals reduced both membership and religiosity in the Catholic Church. Because government spending on welfare may substitute for the religious provision of social services, we consider whether this plausibly exogenous decline in religiosity affected several measures of the public taste toward government and spending on welfare between 1990 and 2008. In places where there were more scandals, individuals state a preference for less government provision of social services. In contrast, a higher level of abuse is also associated with an increase in voting for Democratic candidates for President, state legislatures, and the US House of Representatives, and an increase in per capita government welfare spending, although this increase is insufficient to replace the decrease in Catholic-provided charity.
Drawing holograms by hand

Accidental abrasion of a specular surface sometimes produces real and virtual images of the abrading object. Investigation of this phenomenon in 1994 led to a simple technique which almost sounds like a joke: a method for creating white light holograms by scribing interference fringes one at a time onto a plastic plate by hand. The optics of these 'abrasion holograms' is similar to Rainbow holography, and the similarities reveal techniques for controlling distortions, for producing images of opaque objects, as well as for producing animation effects and images that extend out through the film plane. As with any rainbow hologram, spatially coherent or 'point-source' illumination is required, both a transmission mode and a reflection mode exist, and conjugate illumination produces pseudoscopic images. This 'abrasion holography' highlights the fact that the zoneplates comprising a Rainbow hologram function independently not only of illumination frequency but also of fringe spacing. Size-independent fringes suggests that truly enormous holograms can be engraved on a wide variety of very crude everyday surfaces.
Obstacle avoidance for unmanned air vehicles using optical flow probability distributions

In order for an unmanned aerial vehicle (UAV) to safely fly close to the ground, it must be capable of detecting and avoiding obstacles in its flight path. From a single camera on the UAV, the 3D structure of its surrounding environment, including any obstacles, can be estimated from motion parallax using a technique called structure from motion. Most structure from motion algorithms attempt to reconstruct the 3D structure of the environment from a single optical flow value at each feature point. We present a novel method for calculating structure from motion that does not require a precise calculation of optical flow at each feature point. Due to the effects of image noise and the aperture problem, it may be impossible to accurately calculate a single optical flow value at each feature point. Instead we may only be able to calculate a set of likely optical flow values and their associated probabilities or an optical flow probability distribution. Using this probability distribution, a more robust method for calculating structure from motion is developed. This method is being developed for use on a UAV to detect obstacles, but it can be used on any vehicle where obstacle avoidance is needed.
NONCOMMUTATIVE IMAGES OF COMMUTATIVE SPECTRA

We initiate a unified, axiomatic study of noncommutative algebras R whose prime spectra are, in a natural way, finite unions of commutative noetherian spectra. Our results illustrate how these commutative spectra can be functorially "sewn together" to form Spec R. In particular, we construct a bimodule-determined functor Mod Z → Mod R, for a suitable commutative noetherian ring Z, from which there follows a finite-to-one, continuous surjection Spec Z → Spec R. Algebras satisfying the given axiomatic framework include PI algebras finitely generated over fields, noetherian PI algebras, enveloping algebras of complex finite dimensional solvable Lie algebras, standard generic quantum semisimple Lie groups, quantum affine spaces, quantized Weyl algebras, and standard generic quantizations of the coordinate ring of n × n matrices. In all of these examples (except for the non-finitely-generated noetherian PI algebras), Z is finitely generated over a field, and the constructed map of spectra restricts to a surjection Max Z → Prim R.
Characterization of the Critical Density for Percolation in Random Geometric Graphs

Percolation theory has become a useful tool for the analysis of large-scale wireless networks. We investigate the fundamental problem of characterizing the critical density lambdac(d) for d-dimensional Poisson random geometric graphs in continuum percolation theory. By using a probabilistic analysis which incorporates the clustering effect in random geometric graphs, we develop a new class of analytical lower bounds for the critical density lambdac(d). These analytical lower bounds are the tightest known to date, and reveal a deep underlying relationship between clustering effects and percolation phenomena.
QUANTUM MONTE CARLO METHODS IN STATISTICAL MECHANICS

This paper deals with the optimization of trial states for the computation of dominant eigenvalues of operators and very large matrices. In addition to preliminary results for the energy spectrum of van der Waals clusters, we review results of the application of this method to the computation of relaxation times of independent relaxation modes at the Ising critical point in two dimensions.
Characterization Of Imperfections In Thin-Film Multilayer Devices

The fabrication of high reflectivity multilayer minochromators usually involves depositing a greater number of bilayers than the calculated number for perfect multilayers. This deviation from ideal behavior occurs due to the presence of imperfections in layers. These imperfections are strongly dependent on the deposition process employed and the parameters during deposition. An understanding of the types of imperfections present may lead to attempts to minimize them. The imperfections should be taken into consideration for determining the sequence of d-spacing for making a supermirror.
Automatic detection of omissions in translations

ADOMIT is an algorithm for Automatic Detection of OMIssions in Translations. The algorithm relics solely on geometric analysis of bitext maps and uses no linguistic information. This property allows it to deal equally well with omissions that do not correspond to linguistic units, such as might result from word-processing mishaps. ADOMIT has proven itself by discovering many errors in a hand-constructed gold standard for evaluating bitext mapping algorithms. Quantitative evaluation on simulated omissions showed that, even with today's poor bitext mapping technology, ADOMIT is a valuable quality control tool for translators and translation bureaus.
A New H I Survey of Active Galaxies

We have conducted a new Arecibo survey for H I emission for 113 galaxies with broad-line (type 1) active galactic nuclei (AGNs) out to recession velocities as high as ~35,000 km s?1. The primary aim of the study is to obtain sensitive H I spectra for a well-defined, uniformly selected sample of active galaxies that have estimates of their black hole masses in order to investigate correlations between H I properties and the characteristics of the AGNs. H I emission was detected in 66 out of the 101 (65%) objects with spectra uncorrupted by radio frequency interference, among which 45 (68%) have line profiles with adequate signal-to-noise ratio and sufficiently reliable inclination corrections to yield robust deprojected rotational velocities. This paper presents the basic survey products, including an atlas of H I spectra, measurements of H I flux, line width, profile asymmetry, optical images, optical spectroscopic parameters, as well as a summary of a number of derived properties pertaining to the host galaxies. To enlarge our primary sample, we also assemble all previously published H I measurements of type 1 AGNs for which we can estimate black hole masses, which total an additional 53 objects. The final comprehensive compilation of 154 broad-line active galaxies, by far the largest sample ever studied, forms the basis of our companion paper, which uses the H I database to explore a number of properties of the AGN host galaxies.
The Effects of Decimalization on Return Volatility Components, Serial Correlation and Trading Costs

We examine the composition of return volatility, serial correlation, and trading costs before and after decimalization on the New York Stock Exchange. We decompose the variance of price changes into components associated with public news, rounding errors, and market-making frictions. We find that when stocks move from a fractional to a decimal trading system, the variance components due to market-making frictions and rounding errors decline significantly, whereas the component due to public news remains unchanged. The serial correlation of price changes weakens substantially after decimalization. The uninformed component of bid-ask spreads decreases significantly whereas the informed component has no significant change.
TESTING THE NO-HAIR THEOREM WITH OBSERVATIONS IN THE ELECTROMAGNETIC SPECTRUM. III. QUASI-PERIODIC VARIABILITY

According to the no-hair theorem, astrophysical black holes are uniquely described by their masses and spins. An observational test of the no-hair theorem can be performed by measuring at least three different multipole moments of the spacetime of a black hole and verifying whether their values are consistent with the unique combinations of the Kerr solution. In this paper, we study quasi-periodic variability observed in the emission from black holes across the electromagnetic spectrum as a test of the no-hair theorem. We derive expressions for the Keplerian and epicyclic frequencies in a quasi-Kerr spacetime, in which the quadrupole moment is a free parameter in addition to mass and spin. We show that, for moderate spins, the Keplerian frequency is practically independent of small deviations of the quadrupole moment from the Kerr value, while the epicyclic frequencies exhibit significant variations. We apply this framework to quasi-periodic oscillations (QPOs) in black hole X-ray binaries in two different scenarios. In the case that a pair of QPOs can be identified as the fundamental g- and c-modes in the accretion disk, we show that the no-hair theorem can be tested in conjunction with an independent mass measurement. If pairs of oscillations are identified with non-parametric resonance of dynamical frequencies in the accretion disk, then testing the no-hair theorem also requires an independent measurement of the black hole spin. In addition, we argue that VLBI observations of Sgr A* may test the no-hair theorem through a combination of imaging observations and the detection of quasi-periodic variability.
Exotic Leptons. Higgs, Flavor and Collider Phenomenology

We study extensions of the standard model by one generation of vector-like leptons with non-standard hypercharges, which allow for a sizable modification of the h → γγ decay rate for new lepton masses in the 300 GeV-1 TeV range. We analyze vacuum stability implications for different hypercharges. Effects in h → Zγ are typically much smaller than in h → γγ, but distinct among the considered hypercharge assignments. Non-standard hypercharges constrain or entirely forbid possible mixing operators with standard model leptons. As a consequence, the leading contributions to the experimentally strongly constrained electric dipole moments of standard model fermions are only generated at the two loop level by the new CP violating sources of the considered setups. We derive the bounds from dipole moments, electro-weak precision observables and lepton flavor violating processes, and discuss their implications. Finally, we examine the production and decay channels of the vector-like leptons at the LHC, and find that signatures with multiple light leptons or taus are already probing interesting regions of parameter space.
The Social Capital Paradigm: Bridging across Disciplines

Much of human behavior does not appear to be motivated by selfish preferences for increases in physical goods and services. Examples of such behavior include donations to charities, putting oneself in harm's way to protect a friend or family member, unwillingness to move from one's community for a significant pay increase, offering preferential terms of trade to friends in exchange for physical goods and services, gift giving, volunteering, and attachment to things with little physical value. The social capital paradigm explains some of these nonmaterial-oriented behaviors by integrating behavioral concepts and assumptions from the fields of economics (capital, in particular), psychology (e.g., Maslow's hierarchy of needs), and sociology (institutions and power). A paradigm is a description of a subject that includes definitions, identification of and descriptions of variables, and expected cause and effect relationships. The social capital paradigm describes the influence of relationships on social, emotional, and economic transactions. Robison, Siles, and Schmid describe a social capital paradigm that includes social capital, socio-emotional goods, attachment values, networks, institutions, and power.
Limit theorems for Betti numbers of random simplicial complexes

There have been several recent articles studying homology of various types of random simplicial complexes. Several theorems have concerned thresholds for vanishing of homology, and in some cases expectations of the Betti numbers. However little seems known so far about limiting distributions of random Betti numbers. In this article we establish Poisson and normal approximation theorems for Betti numbers of different kinds of random simplicial complex: ErdősRenyi random clique complexes, random Vietoris-Rips complexes, and random Cech complexes. These results may be of practical interest in topological data analysis.
Use of (±)-isopinocampheyldichloroborane for the efficient synthesis of unsymmetrical ketones via stepwise hydroboration of alkenes

A convenient, one-pot synthesis of unsymmetrical ketones has been developed making use of the in situ reduction — hydroboration reactions of readily prepared and stable (±)-isopinocampheyldichloroborane.
Supporting nested OpenMP parallelism in the TAU performance system

Nested OpenMP parallelism allows an application to spawn teams of nested threads. This hierarchical nature of thread creation and usage poses problems lbr performance measurement tools that must determine thread context to properly maintain per-thread performance data. In this paper we describe the problem and a novel solution for identifying threads uniquely. Our approach has been implemented in the TAU performance system and has been successfully used in profiling and tracing OpenMP applications with nested parallelism. We also describe how extensions to the OpenMP standard can help cool developers uniquely identify threads.
3C 273 : A Star-Like Object with Large Red-Shift

In the early 1960s, astronomers were puzzled by quasars — sources of intense radio emission that seemed to be stars, but had unintelligible optical spectra. In 1963, Maarten Schmidt solved the puzzle by recognizing the Balmer lines of hydrogen, strongly redshifted, in the spectrum of the quasar 3C 273. Schmidt reached the "most direct and least objectionable" conclusion, that 3C 273 was no star, but the enormously bright nucleus of a distant galaxy.
A high-accuracy digital star tracker for advanced planetary missions.

The digital star tracker represents a novel departure from previous analog designs in terms of circuit implementation and operational capabilities. As an element of an all-digital spacecraft control system, it combines proven low-level analog signal processing with digital error control and command functions. Additional capabilities that are obtainable with the digital circuitry include programmable intensity threshold gates, commanded electronic pointing control, and an acquisition/control algorithm which minimizes the effects of straylight disturbances. The capabilities inherent in the implementation have been successfully demonstrated in a laboratory model of the instrument.
An Active Control Strategy for Achieving Weak Radiator Structures

A general control strategy is presented for active suppression of total radiated sound power from harmonically excited structures based on the measurement of their response. Using the measured response of the structure together with knowledge of its structural mobility, an equivalent primary excitation force is found at discrete points along the structure. Using this equivalent primary force and performing a quadratic optimization of the power radiated from the structure, a set of control forces is found at selected points on the structure that results in minimum radiated sound power. A numerical example of this strategy is presented for a simply supported beam in a rigid baffle excited by a harmonic plane wave incident at an oblique angle. A comparison of the response of the beam with and without control forces shows a large reduction in the controlled response displacement magnitude. In addition, as the result of the action of the control forces, the magnitude of the wave number spectrum of the beam’s response in the supersonic region is decreased substantially. The effect of the number and location of the actuators on reductions in sound power level is also studied. The actuators located at the anti-nodes of structural modes within the supersonic region together with those lcoated near boundaries are found to be the most effective in controlling the radiation of sound from a structure.
Healthy Eating in Summer Day Camps: The Healthy Lunchbox Challenge

Abstract Objective To describe the development and evaluation of Healthy Lunchbox Challenge , a nutrition program targeting staff, parents, and children in summer day camps (SDCs). Methods A single-group, pre/post-assessment design was used during summer, 2011(baseline) and 2012 (intervention). Four community-based SDCs in South Carolina participated. Intervention components were applied over the 11-week SDC program (2012) and consisted of (1) parent/staff education on Building a Better Lunchbox, and (2) a child/staff incentive program. Child and staff foods and beverages were assessed via direct observation (1,977 children and 241 staff). Percentages of foods and beverages brought by children and staff during the intervention were compared with baseline measures using mixed-effects regression models. Results The percentage of children bringing fruits, vegetables, and water increased from 31% to 42% ( P = .01), 5% to 16% ( P = .01), and 47% to 60% ( P = .01) from baseline to post-assessment. Staff fruits and vegetables increased from 30% to 47% ( P = .03) and 9% to 22% ( P = .03). A slight decrease was observed for staff water (64% to 58%); however, this was not statistically significant. Decreases in low-nutrient-dense foods and beverages were also observed. Conclusions and Implications The Healthy Lunchbox Challenge represents a low-cost, innovative way to influence the nutritional content of child and staff foods and beverages in SDCs.
Investors' heterogeneity, prices, and volume around the ex-dividend day

This paper analyzes the relationship between tax heterogeneity and the behavior of stock prices and trading volume around the ex-dividend day within an equilibrium framework. We conclude that, even in a world without transaction costs, the price drop on the ex-day need not be equal to the dividend amount. Our model accounts for the higher market trading volume around the ex-day, and shows this to be a function of tax heterogeneity among traders. We show that the volume of trade around the ex-day contains information about investors' tax preferences above and beyond the information contained in the ex-day price alone. Consistent with the model's predictions, our empirical analysis reveals that as the risk associated with the ex-dividend day increases, or tax heterogeneity decreases, trading volume decreases.
Venture capital contracting under asymmetric information

Abstract A model is developed wherein entrepreneurs and venture capitalists contract under symmetric information. Asymmetric information may arise following first contracting. It is shown this can lead to debt infeasibility and preferred equity usage. Control is linked to choice between common and preferred. Results are robust to multiperiod extensions. Roles of convertible preferred, retained equity, and debt in IPOs are considered. An empirical survey of venture capital firms is presented demonstrating preferred dominates in early financing. Debt and common are used far less – generally at later stages under lower probability of asymmetric information. These results agree with the theory's implications.
Multidimensional Timestamp Protocols for Concurrency Control

We propose multidimensional timestamp protocols for concurrency control in database systems where each transaction is assigned a timestamp vector containing multiple elements. The timestamp vectors for two transactions can be equal if timestamp elements are assigned the same values. The serializability order among the transactions is determined by a topological sort of the corresponding timestamp vectors. The timestamp in our protocols is assigned dynamically and is not just based on the starting/finishing time as in conservative and optimistic timestamp methods. The concurrency control can be enforced based on more precise dependency information derived dynamically from the operations of the transactions. Several classes of logs have been identified based on the degree of concurrency or the number of logs accepted by a concurrency controller. The class recognized by our protocols is within D-serializable (DSR), and is different from all previously known classes such as two phase locking (2PL), strictly serializable (SSR), timestamp ordering (TO), which have been defined in literature. The protocols have been analyzed to study the complexity of recognition of logs. We briefly discuss the implementation of the concurrency control algorithm for the new class, and give a timestamp vector processing mechanism. The extension of the protocols for nested transaction and distributed database models has also been included.
Open skies over the Middle East

The dynamism of air traffic markets in the Middle East obscures the persistence of restrictions on international competition. But how important are such restrictions for passenger traffic? This paper uses detailed data on worldwide passenger aviation to estimate the effect of air transport policy on international air traffic. The policy variable is a quantitative measure of the commitments under international agreements. The paper analyzes, for the first time, not only bilateral agreements, but also plurilateral agreements such as the one between Arab states. The analysis finds that more liberal policy is associated with greater passenger traffic between countries. Higher traffic levels appear to be driven primarily by larger numbers of city pairs being served, rather than by more passengers traveling along given routes. To demonstrate the quantitative implication of the estimates, two liberalization scenarios in the Middle East are evaluated. Deepening the plurilateral agreement among Arab states would lead to a 30 percent increase in intraregional passenger traffic. Widening the agreement to include Turkey would generate significantly larger gains because current policy vis-a-vis Turkey is much more restrictive.
Liminalizing Progressive Efforts in Chicago: Moving Forward and Past Violence

This article focuses on the framing of pervasive violence in South Side Chicago neighborhoods, subsequently offering a different lens to highlight the contributions and progressive efforts stemming from individuals residing in these areas. There remains a necessary shift from the passive images of those killed by violent acts to the active efforts of nonprofits working to decrease violence as well as educational programs focusing on interpersonal skills, mediation, and emotional intelligence.
A Game-Theoretic Model of E-Marketplace Participation Growth

Despite their potential to significantly reduce transaction costs for both buyers and sellers, e-marketplaces have struggled. Recent literature has examined the value propositions of e-marketplaces and proposed conceptual frameworks for their analysis. In this research, we move beyond conceptual analysis by developing a game-theoretic model of return-on-investment (ROI)-driven e-marketplace participation growth. This model provides insights into expected e-marketplace growth and participation, and can be used to determine both the viability and expected long-run size of a given e-marketplace. Our results indicate that the pricing policy of the e-marketplace intermediary can affect the rate at which participation grows and, therefore, sentiment about its prospects. We focus on e-marketplaces that add value to buyers and sellers by increasing the efficiency of administrative tasks but also simultaneously add value to buyers and reduce value to sellers by lowering prices for goods purchased. Value to participants in these e-marketplaces is determined by the volume of transactions that can be conducted using the e-marketplace, resulting in a two-sided network effect--buyers reacting to sellers and sellers reacting to buyers. The game-theoretic model identifies an e-marketplace equilibrium at which participation growth is predicted to stop.
Functional dyspepsia: A new Rome III paradigm

Functional dyspepsia (FD) is a condition commonly seen in gastroenterological practice. With the introduction of Rome III criteria in 2006, a new approach for categorizing patients has been recommended. The diagnostic criteria suggest that meal-related and pain-predominant symptom groupings that presumably have distinct pathophysiologic mechanisms and potentially different therapeutic targets exist. The new classification is in the early stages of testing; in the meantime, the umbrella term of FD should continue to be utilized in clinical practice. Treatment of FD remains a major challenge. Unfortunately, most of the agents used in practice have limited or no evidence of efficacy, and the results typically are short-lived once therapy is ceased. Appropriate therapy currently is based on a consideration of putative pathophysiologic mechanisms. Testing for and eradicating Helicobacter pylori is a first-line strategy irrespective of the symptom pattern. In patients who have epigastric pain, antisecretory agents are recommended. Antacids, bismuth, and sucralfate seem to be no better than placebo. For meal-related symptoms such as postprandial fullness or early satiety, prokinetics may confer some benefit. However, few choices are available, and the efficacy for those drugs on the market is limited at best. Antidepressants are of uncertain efficacy but are widely used. Psychological therapies seem promising and may confer benefits on both pain and meal-related symptoms. Efficacy of complementary medicines has been suggested in controlled trials, but more data are needed. Emerging treatments include gastric fundus relaxors and visceral analgesics, although their application in FD is still in the preliminary stages.
Two-dimensional defect modes in optically induced photonic lattices

Localized linear modes due to bandgap guidance in two-dimensional photonic lattices with a repulsive defect are investigated theoretically. It is shown that the negative defect can not only guide fundamental modes, but also dipole modes and vortex modes.
Validation of a CFD Methodology for Positive Displacement LVAD Analysis Using PIV Data

Computational fluid dynamics (CFD) is used to asses the hydrodynamic performance of a positive displacement left ventricular assist device. The computational model uses implicit large eddy simulation direct resolution of the chamber compression and modeled valve closure to reproduce the in vitro results. The computations are validated through comparisons with experimental particle image velocimetry (PIV) data. Qualitative comparisons of flow patterns, velocity fields, and wall-shear rates demonstrate a high level of agreement between the computations and experiments. Quantitatively, the PIV and CFD show similar probed velocity histories, closely matching jet velocities and comparable wall-strain rates. Overall, it has been shown that CFD can provide detailed flow field and wall-strain rate data, which is important in evaluating blood pump performance.
WAVELET-DOMAIN REGRESSION AND PREDICTIVE INFERENCE IN PSYCHIATRIC NEUROIMAGING

An increasingly important goal of psychiatry is the use of brain imaging data to develop predictive models. Here we present two contributions to statistical methodology for this purpose. First, we propose and compare a set of wavelet-domain procedures for fitting generalized linear models with scalar responses and image predictors: sparse variants of principal component regression and of partial least squares, and the elastic net. Second, we consider assessing the contribution of image predictors over and above available scalar predictors, in particular via permutation tests and an extension of the idea of confounding to the case of functional or image predictors. Using the proposed methods, we assess whether maps of a spontaneous brain activity measure, derived from functional magnetic resonance imaging, can meaningfully predict presence or absence of attention deficit/hyperactivity disorder (ADHD). Our results shed light on the role of confounding in the surprising outcome of the recent ADHD-200 Global Competition, which challenged researchers to develop algorithms for automated image-based diagnosis of the disorder.
First experimental evidence of potassium ordering in layered k4co7o14.

The layered P2−K4Co7O14 oxide has been prepared and characterized by means of X-ray diffraction, electrical conductivity, thermopower, and magnetic measurements. The crystal structure of K4Co7O14 (...
More spectral bounds on the clique and independence numbers

We give some new bounds for the clique and independence numbers of a graph in terms of its eigenvalues. In particular we prove the following results. Let G be a graph of order n, average degree d, independence number @a(G), and clique number @w(G). (i) If @m"n is the smallest eigenvalue of G, then@w(G)>=1+dn(n-d)(d-@m"n). Equality holds if and only if G is a complete regular @w-partite graph. (ii) if @m"n@? is the smallest eigenvalue of the complement of G, and 2=(nd+1-1)(lnd+1-@m"n@?-lnln(d+1)). For d sufficiently large this inequality is tight up to factor of 4 for almost all d-regular graphs.