cssi/SciSciGPT-SciSciNet huggingface dataset:
The American Board of Thoracic Surgery: update.

The primary purpose of the American Board of Thoracic Surgery (ABTS) is to protect the public by establishing and maintaining high standards in thoracic surgery. To achieve these objectives, the Board has developed qualifications for examination and procedures for certification and maintenance of certification. During the past few years, the ABTS initiated a new process for subspecialty certification in congenital cardiac surgery; a new process for maintenance of certification in accordance with requirements set forth by the American Board of Medical Specialties (ABMS); and collaborated with other organizations including the Residency Review Committee for Thoracic Surgery (RRC-TS), the Joint Council for Thoracic Surgical Education (JCTSE) and the Thoracic Surgery Directors Association (TSDA) to address some of the challenges currently facing our specialty. This report summarizes ABTS activities during the past 2 years.
Leveling the Playing Field: Sincere and Sophisticated Players in the Boston Mechanism

Empirical and experimental evidence suggests different levels of sophistication among families in the Boston Public School student assignment plan. We analyze the preference revelation game induced by the Boston mechanism with sincere players who report their true preferences and sophisticated players who play a best response. We characterize the set of Nash equilibrium outcomes as the set of stable matchings of a modified economy, where sincere students lose priority to sophisticated students. Any sophisticated student weakly prefers her assignment under the Pareto-dominant Nash equilibrium of the Boston mechanism to her assignment under the recently adopted student-optimal stable mechanism. (JEL D82, I21)
Intramolecular silicon-assisted cross-coupling reactions: General synthesis of medium-sized rings containing a 1,3-cis-cis diene unit

The combination of ring-closing metathesis and Pd-catalyzed, silicon-assisted intramolecular cross-coupling has been developed to provide an effective and powerful method for construction of medium-sized rings with an internal 1,3-cis-cis diene unit. Allylic alcohols bearing a Z-iodoalkenyl tether can be silylated with chlorodimethylvinylsilane and subjected to Mo-catalyzed ring-closing metathesis to form unsaturated siloxanes. Activation of the siloxane with tetrabutylammonium fluoride in the presence of [allylPdCl](2) leads to high yielding ring-closing reactions to form 9-, 10-, 11- and 12-membered rings. Extension to the synthesis of 9-membered ring unsaturated ethers has also been accomplished. Noteworthy features of this process include: (1) a highly stereospecific intramolecular coupling process, (2) flexible positioning of the hydroxy group, and (3) potential extension to other medium-sized carbocycles and heterocycles.
The Ofpe/WN9 Stars in M33

We present Hubble Space Telescope/STIS Ultraviolet spectra of the six known Ofpe/WN9 stars ("slash stars") in M33. These stars were selected for showing the characteristics of the Ofpe/WN9 class from previous optical ground-based spectroscopy. The UV spectra are rich in wind lines whose strength and terminal velocity vary greatly across our target sample. We analyze the STIS spectra with non-LTE, line-blanketed, spherical models with hydrodynamics, computed with the WM-BASIC code. We find C to be underabundant and N overabundant with respect to the solar values, with a ratio (by mass) of C/N between 0.02 and 0.9 across the sample. Some stars show very conspicuous wind lines (P Cygni profiles), while two stars have extremely weak winds. The mass-loss rates thus vary greatly across the sample. The mass-loss rates of the hottest stars are lower than typical values of WNL stars but higher than expected for normal Population I massive stars. There is indication that the mass-loss rates may be variable in time. The C/N ratio and the other physical parameters derived by the spectral modeling (Teff, Lbol, mass) are consistent with evolutionary calculations for objects with moderately high initial masses (≈30-50 M☉), evolving toward the WNL stage through an enhanced mass-loss phase.
Synthesis of 9-(2-fluorobenzyl)-6-methylamino-9H-purine

Synthesis of 9-(2-fluorobenzyl)-6-methylamino-9H-purine (1) from nine different precursors is reported. Compound 1 was prepared by methylamination of 6-chloro-9-(2-fluorobenzyl)-9H-purine (4), by alkylation of 6-methylaminepurine (5) or form 9-(2-fluorobenzyl)-1-methyladeninium iodide (8) via the Dimroth rearrangement. Selective 2-step methylation of 6-aminopurine 6 was accomplished by hydride reduction of 6-formamidopurine 9, 6-dimethylaminomethyleneaminopurine 10 or 6-phenylthiomethyl purine 11 to give 1. Compound 1 was also prepared by dethiation or reductive dechlorination of 2-methylthiopurine 16 or 8-chloropurine 19, respectively, or by hydrolysis of 6-N-methylformamidopurine 12, which was prepared from 6-dimethylaminopurine 13 by selective oxidation.
A contour line of the continuum Gaussian free field

Consider an instance $$h$$ of the Gaussian free field on a simply connected planar domain $$D$$ with boundary conditions $$-\lambda $$ on one boundary arc and $$\lambda $$ on the complementary arc, where $$\lambda $$ is the special constant $$\sqrt{\pi /8}$$ . We argue that even though $$h$$ is defined only as a random distribution, and not as a function, it has a well-defined zero level line $$\gamma $$ connecting the endpoints of these arcs, and the law of $$\gamma $$ is $$\mathrm{SLE}(4)$$ . We construct $$\gamma $$ in two ways: as the limit of the chordal zero contour lines of the projections of $$h$$ onto certain spaces of piecewise linear functions, and as the only path-valued function on the space of distributions with a natural Markov property. We also show that, as a function of $$h, \gamma $$ is “local” (it does not change when $$h$$ is modified away from $$\gamma $$ ) and derive some general properties of local sets.
Structured query reformulations in commerce search

Recent work in commerce search has shown that understanding the semantics in user queries enables more effective query analysis and retrieval of relevant products. However, due to lack of sufficient domain knowledge, user queries often include terms that cannot be mapped directly to any product attribute. For example, a user looking for designer handbags might start with such a query because she is not familiar with the manufacturers, the price ranges, and/or the material that gives a handbag designer appeal. Current commerce search engines treat terms such as designer as keywords and attempt to match them to contents such as product reviews and product descriptions, often resulting in poor user experience. In this study, we propose to address this problem by reformulating queries involving terms such as designer, which we call modifiers, to queries that specify precise product attributes. We learn to rewrite the modifiers to attribute values by analyzing user behavior and leveraging structured data sources such as the product catalog that serves the queries. We first produce a probabilistic mapping between the modifiers and attribute values based on user behavioral data. These initial associations are then used to retrieve products from the catalog, over which we infer sets of attribute values that best describe the semantics of the modifiers. We evaluate the effectiveness of our approach based on a comprehensive Mechanical Turk study. We find that users agree with the attribute values selected by our approach in about 95% of the cases and they prefer the results surfaced for our reformulated queries to ones for the original queries in 87% of the time.
A Smaller Radius for the Transiting Exoplanet WASP-10b

We present the photometry of WASP-10 during a transit of its short-period Jovian planet. We employed the novel point-spread function shaping capabilities of the Orthogonal Parallel Transfer Imaging Camera mounted on the UH 2.2 m telescope to achieve a photometric precision of 4.7 × 10^(–4) per 1.3 minute sample. With this new light curve, in conjunction with stellar evolutionary models, we improve on existing measurements of the planetary, stellar, and orbital parameters. We find a stellar radius R^* = 0.698 ± 0.012 R_☉ and a planetary radius R_P = 1.080 ± 0.020 R_Jup. The quoted errors do not include any possible systematic errors in the stellar evolutionary models. Our measurement improves the precision of the planet's radius by a factor of 4, and revises the previous estimate downward by 16% (2.5σ, where σ is the quadrature sum of the respective confidence limits). Our measured radius of WASP-10b is consistent with previously published theoretical radii for irradiated Jovian planets.
Unified Equation of Motion (UEM) Approach as Applied to S1 Turbomachinery Problems

Incompressible, blade-to-blade (S1 surface) flow solutions for stators and rotors of turbomachines are obtained utilizing an approach which combines the equations of motion into a single elliptic, second-order partial differential equation for the streamline field. This Unified Equation of Motion (UEM) is obtained from the momentum equation which is modified by using a stream function that satisfies the continuity equation identically. The unified equation is solved numerically by use of a finite difference technique. The velocity field is determined by differentiation of the stream function field and use of the computed streamlines. The pressure field is then determined from an energy relation along the streamlines. The present method is similar to the classical Streamline Curvature Method (SLCM) in that a computation grid is not required; however, the ellipticity of the flow field is preserved directly by the unified equation of motion. The UEM solution is substantially more stable than the SLC method and yields the periodic stagnation streamline directly. Body-fitted curvilinear coordinates (quasi-orthogonals and streamlines) are generated naturally by the UEM solution. A number of comparisons of the results of the present method are made with experimental data and results of other numerical methods. These comparisons are made for incompressible two dimensional and quasi-three dimensional stationary and rotating blade sections. There is general agreement with accepted analysis procedures.Copyright © 1987 by ASME
The effects of sulfur on the dissolution of nickel

Abstract The influence of S on the dissolution of Ni in 0.5 N nitric and 1.0 N sulfuric acid solutions has been examined by both electrochemical and surface analysis methods. Vacuum-melted pure Ni, S-implanted Ni, and Ni-S alloys were studied. Sulfur, in a surface sulfide state, was found to increase the dissolution rates of Ni at active potentials by a factor of 50. For pure Ni (with bulk S concentrations as low as 2 ppm), S accumulated on the surface during dissolution at active potentials, causing the rate of Ni dissolution to increase with time. In contrast to earlier studies, IR -corrected electrochemical data indicated that S did not inhibit passivation for any of the three specimen types or two solutions examined in this study.
Universal DNA tag systems: a combinatorial design scheme

Custom-designed DNA arrays offer the possibility of simultaneously monitoring thousands of hybridization reactions These arrays show great potential for many medical and scientific applications such as polymorphism analysis and genotyping. Relatively high costs are associated with the need to specifically design and synthesize problem specific arrays. Recently, an alternative approach was suggested that utilizes fixed, universal arrays. This approach presents an interesting design problem—the arrays should contain as many probes as possible, while minimizing experimental errors caused by cross-hybridization. We use a simple thermodynamic model to cast this design problem in a formal mathematical framework. Employing new combinatorial ideas, we derive an efficient construction for the design problem, and prove that our construction is near-optimal.
The Spectroscopic Orbits of Five Solar-type, Single-lined Binaries

We have determined spectroscopic orbits for five single-lined spectroscopic binaries, HD 100167, HD 135991, HD 140667, HD 158222, HD 217924. Their periods range from 60.6 to 2403 days and the eccentricities from 0.20 to 0.84. Our spectral classes for the stars confirm that they are of solar type, F9-G5, and all are dwarfs. Their [Fe/H] abundances, determined spectroscopically, are close to the solar value and on average are 0.12 greater than abundances from a photometric calibration. Four of the five stars are rotating faster than their predicted pseudosynchronous rotational velocities.
Pre-empting public regulation with private food quality standards

There has been a great deal of recent growth in the area of private food quality standards. This article analyses the incentives for setting private quality standards before governments do so. Since food quality standards are generally multifaceted, different types of standards will affect revenues differently. Our model shows that private firms can pre-empt public regulation by setting their own private food quality standards in order to choose the type of standards that minimises their costs. The emergence of private food standards in grocery retailing is discussed in this context. Oxford University Press and Foundation for the European Review of Agricultural Economics 2009; all rights reserved. For permissions, please email journals.permissions@oxfordjournals.org, Oxford University Press.
Quantum Mechanical Effects in Stimulated Optical Emission

An analysis of a three-level system using time-dependent perturbation theory shows that two distinct photon-emission processes take place within such a system when stimulated optical emission occurs: one-and two-photon transitions. The two-photon transition consists of the emission of a stimulated photon followed by the absorption of a coherent pump photon. In three-level systems which possess a narrow pump level, two-photon transitions are dominant at high pump powers while the maser line is split into two lines due to the modulation of the wave function at an angular frequency determined by the rate of pumping. This might lead to the possibility of frequency-modulating the maser line. These results are extended qualitatively to include optical masers which possess broad pump-bands.
Prevalence of type 2 diabetes mellitus among persons with hepatitis C virus infection in the United States.

According to this national survey, type 2 diabetes occurs more often in persons with hepatitis C virus infection who are older than 40 years of age.
Cell density as a selective parameter in Tetrahymena

Abstract Cells of various metabolic states of Tetrahymena pyriformis were separated by banding in linear density gradients of Ficoll. Whereas log phase cultures generated three distinct bands, stationary cultures produced only two, and starved cells demonstrated a unique, higher density. The value of this observation for the positive selection of nutritional auxotrophs and temperature sensitive mutants is discussed. In addition, a unique downward migration of a band of cells separated by the centrifugation is demonstrated and discussed.
Estimating Income Mobility from Census Data

Abstract In this article we propose a methodology for estimating income- mobility matrices from census data. The methodology is applied to Brazil, using 1970 and 1980 census data. Goodness-of-fit tests show that the method yields estimates of income mobility that are both accurate and unbiased. For Brazil the results indicate that workers at all income levels benefited from growth between 1970 and 1980 but that Brazil's growth was nevertheless unequalizing: workers who started with higher incomes in 1970 benefited more from growth than workers who started with lower incomes. The estimated income-mobility matrices were then used to calculate life-cycle incomes. They indicate that upward mobility made life-cycle income distributions more equal than the distribution of starting incomes for workers of both sexes.
Universal Dumping of Homogeneous Products

Contrary to predictions from traditional comparative advantage analysis, a class of models with imperfect competition predicts intra-industry trade in homogeneous goods. Brander and Krugman offer a model with two countries and one firm in each country which generates the outcome that both firms dump into the export market (reciprocal dumping). The present paper determines the extent to which higher dimensionality alters this outcome by introducing a model with several firms in each of several countries. It is shown that dumping is universal. Thus, whenever trade occurs dumping occurs.
Relativistic Calculations of Coalescing Binary Neutron Stars

We have designed and tested a new relativistic Lagrangian hydrodynamics code, which treats gravity in the conformally flat approximation to general relativity. We have tested the resulting code extensively, finding that it performs well for calculations of equilibrium single-star models, collapsing relativistic dust clouds, and quasi-circular orbits of equilibrium solutions. By adding a radiation reaction treatment, we compute the full evolution of a coalescing binary neutron star system. We find that the amount of mass ejected from the system, much less than a per cent, is greatly reduced by the inclusion of relativistic gravitation. The gravity wave energy spectrum shows a clear divergence away from the Newtonian point-mass form, consistent with the form derived from relativistic quasi-equilibrium fluid sequences.
Hα Activity of Old M Dwarfs: Stellar Cycles and Mean Activity Levels for 93 Low-mass Stars in the Solar Neighborhood

Through the McDonald Observatory M Dwarf Planet Search, we have acquired nearly 3000 high-resolution spectra of 93 late-type (K5-M5) stars over more than a decade using the High Resolution Spectrograph on the Hobby-Eberly Telescope. This sample provides a unique opportunity to investigate the occurrence of long-term stellar activity cycles for low-mass stars. In this paper, we examine the stellar activity of our targets as reflected in the Hα feature. We have identified periodic signals for six stars, with periods ranging from days to more than 10 years, and find long-term trends for seven others. Stellar cycles with P ≥ 1 year are present for at least 5% of our targets. Additionally, we present an analysis of the time-averaged activity levels of our sample, and search for correlations with other stellar properties. In particular, we find that more massive, earlier type (M0-M2) stars tend to be more active than later type dwarfs. Furthermore, high-metallicity stars tend to be more active at a given stellar mass. We also evaluate Hα variability as a tracer of activity-induced radial velocity (RV) variation. For the M dwarf GJ 1170, Hα variation reveals stellar activity patterns matching those seen in the RVs, mimicking the signal of a giant planet, and we find evidence that the previously identified stellar activity cycle of GJ 581 may be responsible for the recently retracted planet f in that system. In general, though, we find that Hα is not frequently correlated with RV at the precision (typically 6-7 m s–1) of our measurements.
Near-space station-keeping performance of a large high-altitude notional airship

A key technical challenge for high-altitude (near-space) concepts is autonomous station keeping, or the ability to remain fixed over a geo-location in the presence of winds. Although operational altitudes of 65,000 ft. altitude and above are above weather (i.e., storms, rain), winds still exist. And to station keep in the presence of these winds requires propulsive power. This paper focuses on the analysis of the station keeping performance of a notional solar-powered airship operating at an altitude around 65,000. The vehicle has a lifting-gas volume of 6.1 million ft 3 , is 450 ft in length, and is solar-electric powered with the entire upper surface covered by solar cells. Electric motors and propellers provide propulsion, additional on-board power is required for the payload and auxiliary equipment, and batteries are used for power storage. In this paper, the aerodynamic drag of the vehicle is estimated, the wind environment is characterized, and the solar-power available is determined for several geo-locations and time of year. This power available is then compared to the power required for station keeping in the presence of winds. It is shown that due to diurnal solar variations and season winds a large airship may be unable to meet station-keeping performance requirements in certain months of the year due to power limitations
Stochastic Liouville equations for femtosecond stimulated Raman spectroscopy

Electron and vibrational dynamics of molecules are commonly studied by subjecting them to two interactions with a fast actinic pulse that prepares them in a nonstationary state and after a variable delay period T, probing them with a Raman process induced by a combination of a broadband and a narrowband pulse. This technique, known as femtosecond stimulated Raman spectroscopy (FSRS), can effectively probe time resolved vibrational resonances. We show how FSRS signals can be modeled and interpreted using the stochastic Liouville equations (SLE), originally developed for NMR lineshapes. The SLE provide a convenient simulation protocol that can describe complex dynamics caused by coupling to collective bath coordinates at much lower cost than a full dynamical simulation. The origin of the dispersive features that appear when there is no separation of timescales between vibrational variations and the dephasing time is clarified.
Toward realistic haptic rendering of surface textures

The emerging science of haptic rendering consists of delivering properties of physical objects through the sense of touch. Owing to the recent development of sophisticated haptic-rendering algorithms, users can now experience virtual objects through touch in many exciting applications, including surgical simulations, virtual prototyping, and data per-ceptualization. Haptics holds great promise to enrich the sensory attributes of virtual objects that these systems can produce.
Multi-intersection Traffic Light Control Using Infinitesimal Perturbation Analysis

Abstract We address the traffic light control problem for multiple intersections in tandem by viewing it as a stochastic hybrid system and developing a Stochastic Flow Model (SFM) for it. Using Infinitesimal Perturbation Analysis (IPA), we derive on-line gradient estimates of a cost metric with respect to the controllable green and red cycle lengths. The IPA estimators obtained require counting traffic light switchings and estimating car flow rates only when specific events occur. The estimators are used to iteratively adjust light cycle lengths to improve performance and, in conjunction with a standard gradient-based algorithm, to obtain optimal values which adapt to changing traffic conditions. Simulation results are included to illustrate the approach.
Operator Theory on Noncommutative Domains

In this volume the author studies noncommutative domains $\mathcal{D}_f\subset B(\mathcal{H})^n$ generated by positive regular free holomorphic functions $f$ on $B(\mathcal{H})^n$, where $B(\mathcal{H})$ is the algebra of all bounded linear operators on a Hilbert space $\mathcal{H}$. Table of Contents: Introduction; Operator algebras associated with noncommutative domains; Free holomorphic functions on noncommutative domains; Model theory and unitary invariants on noncommutative domains; Commutant lifting and applications; Bibliography. (MEMO/205/964)
A Combinatorial Analysis of Interacting Diffusions

We attempt to unify the analysis of several families of naturally occurring multidimensional stochastic processes by studying the underlying combinatorics involved. At equilibrium, the behavior of these processes is determined by the properties of a randomly chosen point of a corresponding polyhedron. How such a randomly chosen point behaves is a difficult question which is intertwined with the geometry and the symmetry of the polyhedron. The simplest of all cases is the simplex where a complete probabilistic study is known. A possible general strategy is through triangulation of the polyhedron where we decompose it as a union of simplices with non-intersecting interiors. In particular we study the case when the polyhedron is a simplicial polytope, since they correspond to the natural examples of stochastic processes. This is the case when the polytope is invariant under a Coxeter group action, which leads to a simple and explicit description of the equilibrium behavior of the stochastic processes in terms of independent and identically distributed Exponential random variables. Another class of examples is furnished by processes indexed by weighted graphs, all of which generate simplicial polytopes with n! faces. We show that the proportion of volume contained in each component simplex corresponds to a probability distribution on the group of permutations, some of which have surprising connections with the classical urn models.
Corporate Disclosure, Market Valuation, and Firm Performance

In this paper, I study the relationship between the Association for Investment Management and Research disclosure rankings and several corporate performance measures. I find a positive relationship between these rankings and stock returns. Furthermore, disclosure rankings are highly correlated with firm value. Specifically, Qs of firms ranked at the top of disclosure rankings are 35% higher than those of firms ranked at the bottom. I also find positive associations between disclosure rankings and future net profit margins, sales growth, and research and development intensity. Finally, I document a positive correlation between changes in disclosure rankings and future earnings surprises.
The X-Ray Photoionized Wind in Cen X-3/V779 Cen

We analyze the ASCA spectrum of the Cen X-3 X-ray binary system in eclipse using atomic models appropriate to recombination-dominated level population kinetics in an overionized plasma. In order to estimate the wind characteristics, we first fit the eclipse spectrum to a single-zone photoionized plasma model. We then fit spectra from a range of orbital phases using global models of photoionized winds from the companion star and the accretion disk that account for the continuous distribution of density and ionization state. We find that the spectrum can be reproduced by a density distribution of the form derived by Castor et al. (1975) for radiation-driven winds with /v∞ consistent with values for isolated stars of the same stellar type. This is surprising because the neutron star is very luminous (~1038 ergs s-1) and the X-rays from the neutron star should ionize the wind and destroy the ions that provide the opacity for the radiation-driven wind. Using the same functional form for the density profile, we also fit the spectrum to a spherically symmetric wind centered on the neutron star, a configuration chosen to represent a disk wind. We argue that the relatively modest orbital variation of the discrete spectrum rules out a disk wind hypothesis.
Intense ion beam neutralization using underdense background plasma

Producing an overdense background plasma for neutralization purposes with a density that is high compared to the beam density is not always experimentally possible. We show that even an underdense background plasma with a small relative density can achieve high neutralization of intense ion beam pulses. Using particle-in-cell simulations, we show that if the total plasma electron charge is not sufficient to neutralize the beam charge, electron emitters are necessary for effective neutralization but are not needed if the plasma volume is so large that the total available charge in the electrons exceeds that of the ion beam. Several regimes of possible underdense/tenuous neutralization plasma densities are investigated with and without electron emitters or dense plasma at periphery regions, including the case of electron emitters without plasma, which does not effectively neutralize the beam. Over 95% neutralization is achieved for even very underdense background plasma with plasma density 1/15th the beam density. We compare results of particle-in-cell simulations with an analytic model of neutralization and find close agreement with the particle-in-cell simulations. Further, we show experimental data from the National Drift Compression experiment-II group that verifies the result that underdense plasma can neutralize intense heavy ion beams effectively.
Efficient Monte Carlo computation of Fisher information matrix using prior information

The Fisher information matrix (FIM) is a critical quantity in several aspects of mathematical modeling, including input selection and confidence region calculation. Analytical determination of the FIM in a general setting, especially in nonlinear models, may be difficult or almost impossible due to intractable modeling requirements or/and intractable high-dimensional integration. To circumvent these difficulties, a Monte Carlo simulation based technique, known as resampling algorithm, is usually recommended, in which values of the log-likelihood function or its exact stochastic gradient computed based on a set of pseudo-data vectors are used. The current work proposes an extension of this resampling algorithm in order to enhance the statistical qualities of the estimator of the FIM. This modified resampling algorithm is useful in those cases when some elements of the FIM are analytically known from prior information and the rest of the elements are unknown. The estimator of the FIM resulting from the proposed algorithm simultaneously preserves the analytically known elements and reduces variances of the estimators of the unknown elements. This is achieved by capitalizing on the information contained in the known elements.
Developments encompassing stress based finite element formulations for materially nonlinear static/dynamic problems

Alternative finite element representations employing stress based element formulations are described for the solution of static/dynamic nonlinear stress analysis problems. In particular, this work investigates the proposed formulations as applied to both static and dynamic situations involving material nonlinearity. The formulations eliminate the need to employ numerical integration in evaluating the stiffness matrix and the residual force vector. Some noteworthy aspects via the present formulations include independence of element integral computations from nonlinearities, introduction of boundary conditions in a direct and natural manner and the applicability to general situations. Numerical test cases are described to validate the present formulations for finite element computations. The overall results show good accuracy and improvement in efficiency for the computations.
REVISITING THE BLACK HOLE MASSES OF SOFT X-RAY-SELECTED ACTIVE GALACTIC NUCLEI

In our previous work, using luminosity and the Hβ FWHM as surrogates for black hole mass (MBH), we compared the black hole masses of narrow-line Seyfert 1 galaxies (NLS1s) and broad-line Seyfert 1 galaxies (BLS1s) in a sample of soft X-ray-selected active galactic nuclei. We found that the distributions of black hole masses in the two populations are statistically different. Recent work shows that the second moment of the Hβ emission line (the line dispersion) is a better estimator of black hole mass than FWHM. To test whether changing the width measure affects our results, we calculate line dispersion-based black hole masses for our soft X-ray-selected sample. We find that using the line dispersion rather than the FWHM as a measure of the gas velocity shifts NLS1 and BLS1 virial product distributions closer together, but they remain distinct. On the MBH-σ* plane, we find that using the line dispersion leaves NLS1s below the MBH-σ* relation, but to a less significant degree than when FWHM is used to calculate black hole masses (the [O III] λ5007 FWHM is used as a surrogate for the bulge stellar velocity dispersion). The level of significance of our findings is such that we cannot draw firm conclusions on the location of the two samples on the MBH-σ* plane. We are still left with two alternative scenarios: either (1) NLS1s lie below the MBH-σ* relation, indicating that their black hole masses are growing, or (2) NLS1s lie on the MBH-σ* relation, so they preferentially reside in smaller mass, less luminous galaxies; the present data do not allow us to choose one over the other. More trustworthy stellar velocity dispersions and accurate black hole mass measurements with reverberation mapping are required for a firmer statement about the locus of NLS1s on the MBH-σ* plane.
Grain Boundary Segregation of Interstitial and Substitutional Impurity Atoms in Alpha-Iron

The macroscopic behavior of polycrystalline materials is influenced by the local variation of properties caused by the presence of impurities and defects. The effect of these impurities at the atomic scale can either embrittle or strengthen grain boundaries (GBs) within. Thus, it is imperative to understand the energetics associated with segregation to design materials with desirable properties. In this study, molecular statics simulations were employed to analyze the energetics associated with the segregation of various elements (helium, hydrogen, carbon, phosphorous, and vanadium) to four 〈100〉 (Σ5 and Σ13 GBs) and six 〈110〉 (Σ3, Σ9, and Σ11 GBs) symmetric tilt grain boundaries in α-Fe. This knowledge is important for designing stable interfaces in harsh environments. Simulation results show that the local atomic arrangements within the GB region and the resulting structural units have a significant influence on the magnitude of binding energies of the impurity (interstitial and substitutional) atoms. These data also suggest that the site-to-site variation of energies within a boundary is substantial. Comparing the binding energies of all 10 boundaries shows that the Σ3(112) boundary possesses a much smaller binding energy for all interstitial and substitutional impurity atoms among the boundaries examined in this study. Additionally, based on the Rice–Wang model, our total energy calculations show that V has a significant beneficial effect on the Fe grain boundary cohesion, while P has a detrimental effect on grain boundary cohesion, much weaker than H and He. This is significant for applications where extreme environmental damage generates lattice defects and grain boundaries act as sinks for both interstitial and substitutional impurity atoms. This methodology provides us with a tool to effectively identify the local as well as the global segregation behavior that can influence the GB cohesion.
A Low-Mass H2 Component to the AU Microscopii Circumstellar Disk

We present a determination of the molecular gas mass in the AU Microscopii circumstellar disk. Direct detection of a gas component to the AU Mic disk has proven elusive, with upper limits derived from ultraviolet absorption line and submillimeter CO emission studies. Fluorescent emission lines of H2, pumped by the O VI λ1032 resonance line through the C-X (1-1) Q(3) λ1031.87 A transition, are detected by the Far Ultraviolet Spectroscopic Explorer. These lines are used to derive the H2 column density associated with the AU Mic system. The derived column density is in the range N(H2) = 1.9 × 1017 to 2.8 × 1015 cm-2, roughly 2 orders of magnitude lower than the upper limit inferred from absorption line studies. This range of column densities reflects the range of H2 excitation temperature consistent with the observations, T(H2) = 800-2000 K, derived from the presence of emission lines excited by O VI in the absence of those excited by Lyα. Within the observational uncertainties, the data are consistent with the H2 gas residing in the disk. The inferred N(H2) range corresponds to H2-to-dust ratios of : 1 and a total M(H2) = 4.0 × 10-4 to 5.8 × 10-6 M⊕. We use these results to predict the intensity of the associated rovibrational emission lines of H2 at infrared wavelengths covered by ground-based instruments, HST NICMOS, and the Spitzer IRS.
Large-amplitude photometric variations of Nereid

Photometric UVBRI and astrometric data on Nereid were collected in June, 1987 using the 0.9-m telescope and CCD camera at the Cerro Tololo Inter-American Observatory. Four astrometric positions and UVBRI reflectances spanning eight days were obtained. From these data, an unusual reflectance spectrum for Nereid was determined. Variability of Nereid was observed in all bandpasses, with an amplitude greater than 1.5 mag and a probable period of between 8 and 24 hr.
Will blade tenderization decrease iridescence in cooked beef semitendinosus muscle

Ten beef semitendinosus muscles were vacuum packaged and stored at 3C. Each muscle was divided into three sections and randomly assigned to one of three blade tenderization treatments (control-zero, one, or two times). Blade-tenderized muscles were cooked to 63C and held for 1 min in a forced-air convection oven at 163C. Cooked muscles were chilled overnight at 3C and sliced by a sharp knife. Panelists (n = 19) evaluated iridescence intensity on a five-point scale (0 = no iridescence, 5 = very strong) and extent of iridescence (0 = no iridescence, 5 = 81–100% affected area). Blade tenderization decreased (P < 0.05) iridescence intensity from 2.37 to 2.02 (5-point scale) and extent of iridescence from 2.18 to 1.83 (control zero versus two passes). Cooking loss increased (P < 0.05) with blade tenderization (30.4% control, 32.6% one pass, 33.7% two passes).
FULLY QUANTIZED MANY PARTICLE THEORY OF A FREE-ELECTRON LASER

A fully quantized many-particle theory of the standard free-electron laser in the small-signal, cold-beam regime is presented. The approach is based on an evaluation of the time-evolution operator in the interaction picture to first order in the quantum-mechanical recoil. For algebraic convenience we use the moving (Bambini-Renieri) frame, in which resonance occurs for zero electron momentum. Though we neglect space-charge effects, genuine many-particle contributions still show up, because the radiation emitted by one electron can be amplified by another electron. Our main results are gross features of the amplification, such as gain and spread, are virtually without many-particle effects. These effects are mainly important in the case of spontaneous emission. For a sufficiently high current, the buildup of the laser field from vacuum is enhanced by amplified spontaneous emission. Incoherence of the spontaneous radiation from several electrons induces deviations from Poisson statistics even if gain is neglected. For a dilute electron beam, spontaneous radiation is slightly antibunched for negative gain. Squeezing is obtained for positive gain independent of the number of electrons. However, owing to some idealizations used in the model, it is uncertain whether this applies to a physically realizable situation.
Implications of adiabatic phases for a vortex in a superconductor film

Abstract Based on ideas of off-diagonal long range order and two-fluid model, we demonstrate that adiabatic phases for a slow motion of a vortex in a superconductor film give rise naturally to the Magnus force at finite temperatures.
How to Reduce Corruption

Africa has not always been corrupt, and some African societies are not corrupt. Nevertheless, for much of Africa, the reduction of corruption is currently an important priority. I review the lessons from Africa’s history, from experience elsewhere, and from economic theory, to develop an agenda for action. Since Africa became corrupt, part of the solution is to understand what caused that change so that the causal factors can be reversed. For example, both widespread economic regulation and weak checks on the performance of public sector employees encouraged corruption. However, once corruption becomes normal, reversing the policies that caused it is not enough. The society needs a ‘big push’ to shock it out of a high-corruption equilibrium. La corruption n’a pas toujours sevi en Afrique et certaines societes africaines ne sont pas victimes de ce fleau. Toutefois, pour une grande partie du continent, la lutte contre la corruption revAt actuellement un caractere hautement prioritaire. Le present article passe en revue les lecons tirees de l’histoire de l’Afrique, fait le point de l’experience acquise dans d’autres regions du monde et analyse les theories economiques en vue d’elaborer un plan d’action. La corruption etant devenue l’apanage de l’Afrique, l’un des moyens de la faire reculer consiste a apprehender les facteurs a l’origine de ce phenomene afin de les inverser. Par exemple, la reglementation economique generalisee et la faiblesse des controles sur le travail des agents de l’Etat sont des facteurs qui ont incitea la corruption. Neanmoins, lorsque la corruption entre dans les moeurs, il ne suffit pas, pour y mettre un terme, d’inverser les politiques qui en sont les causes. La societe doit subir un ‘grand choc’ pour la faire sortir du cycle de la corruption.
A comment on the relationship between differential and dimensional renormalization

Abstract We show that there is a very simple relationship between differential and dimensional renormalization of low-order Feynman graphs in renormalizable massless quantum field theories. The beauty of the differential approach is that it achieves the same finite results as dimensional renormalization without the need to modify the space-time dimension.
Measurement and analysis of large operating systems during system development

Some months ago, representatives of one of the better known software houses contacted us with this proposal: They wished to sell us a tool for advancing, our techniques in developing real-time systems. Their techniques allowed the exact reproduction of any observed sequence of real-time events. Thus, when a particular sequence caused a system error, the sequence could easily be reproduced so that the error could be analyzed and corrected, and the correction verified. A powerful tool, indeed.
The effect of prospective payment on admission and treatment policy: Evidence from inpatient rehabilitation facilities

We examine provider responses to the Medicare inpatient rehabilitation facility (IRF) prospective payment system (PPS), which simultaneously reduced marginal reimbursement and increased average reimbursement. IRFs could respond to the PPS by changing the number of patients admitted, admitting different types of patients, or changing the intensity of care. We use Medicare claims data to separately estimate each type of provider response. We also examine changes in patient outcomes and spillover effects on other post-acute care providers. We find that costs of care initially fell following the PPS, which we attribute to changes in treatment decisions rather than the characteristics of patients admitted to IRFs within the diagnostic categories we examine. However, the probability of admission to IRFs increased after the PPS due to the expanded admission policies of providers. We find modest spillover effects in other post-acute settings and negative health impacts for only one of three diagnostic groups studied.
Cyclotron: a secure, isolated, virtual cycle-scavenging grid in the enterprise

Cycle-scavenging grids appeal to organizations with large numbers of workstations that remain idle outside of normal working hours. This represents a potential source of grid computing cycles, but the security and isolation issues that come with the use of non-dedicated resources have slowed their adoption in the enterprise. In this paper we present Cyclotron, a prototype cycle-scavenging grid solution that leverages virtualization and a declarative security policy-based access control infrastructure, supporting flexible authorization rules and the constrained delegation of access rights, to address these requirements. Copyright © 2009 John Wiley & Sons, Ltd.
NMR pulse relaxation studies on the normal aging and cataractous lens.

Proton NMR pulse relaxation experiments have been performed in this and other laboratories mainly on animal lenses and some human lenses. In order to evaluate T 1 and T 2 analyses as a potentially useful (non-invasive) parameter in delineating lenticular changes in normal aging human rabbit lenses, and in human cataracts, we performed a series of pulse relaxation studies on human eye bank lenses 10 to 93 yr of age, on fresh intact human cataracts and on normal rabbit lenses. Additional spectroscopic studies (fluorescence and 31 P-NMR) were also performed on the lenses in order to correlate these parameters with the data relating to ‘water phases’ in the lens. These experiments demonstrate a potential additional parameter for evaluating ‘molecular’ changes in the aging and cataractous lens.
Total Syntheses of (+)- and (−)-Peribysin E

A convergent, stereocontrolled route to either antipode of the cell adhesion inhibitor, peribysin E, has been achieved from carvone. Highlights of the synthesis include a Diels−Alder reaction to generate a cis-decalin framework, followed by semipinacol-type ring contraction to secure the stereochemistry of the C7 quaternary center. Potential mechanistic pathways for the critical ring contraction were studied through deuterium incorporation studies. In addition, an optimized olefin isomerization/Saegusa oxidation protocol is described for the conversion of [4+2] cycloadducts of 2-(trialkylsilyloxy)-1,3-dienes to 1,6(2H,7H)-naphthalenediones, having stereochemical arrangements not accessible via conventional Robinson annulation protocols. Finally, the ability to independently prepare either enantiomer of peribysin E from the corresponding antipode of carvone led to a reassignment of the absolute configuration of peribysin E.
Castelnuovo–Mumford regularity bounds for singular surfaces

We prove the regularity conjecture, namely Eisenbud–Goto conjecture, for a normal surface with rational, Gorenstein elliptic and log canonical singularities. Along the way, we bound the regularity for a dimension zero scheme by its Loewy length and for a curve allowing embedded or isolated point components by its arithmetic degree.
CASTER - a scintillator-based black hole finder probe

The primary scientific mission of the black hole finder probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X-ray coded-aperture imaging mission operating in the 10-600 keV energy hand, a spectral range that is considered to be especially useful in the detection of black hole sources. The development of new inorganic scintillator materials provides improved performance (for example, with regards to energy resolution and timing) that is well suited to the BHFP science requirements. Detection planes formed with these materials coupled with a new generation of readout devices represent a major advancement in the performance capabilities of scintillator-based gamma cameras. Here, we discuss the coded aperture survey telescope for energetic radiation (CASTER), a concept that represents a BHFP based on the use of the latest scintillator technology.
Abnormal cervical cytology leading to the diagnosis of gastric cancer.

Abstract There have been nine cases reported in the English literature in which the finding of malignant cells on cervical/vaginal cytology led to the diagnosis of primary gastric cancer. We report on a patient with gastric carcinoma, metastatic to the cervix, in which the diagnosis was suspected by the finding of signet ring cells on a Papanicolaou smear of the cervix. Prior to treatment of this patient, concordance of signet ring carcinoma on cervical and ascitic fluid cytology and on cervical and gastric biopsies was documented; this has not been reported previously. Thirty-four additional cases of gastric carcinoma metastatic to the cervix are reviewed. This paper is presented to remind the clinician that, however rare, metastases from the gastrointestinal tract to the Uterine Cervix do occur.