cssi/SciSciGPT-SciSciNet huggingface dataset:
Electromagnetic wave propagation in inhomogeneous multilayered structures of arbitrary thickness-full wave solutions

In this paper, we derive full wave solutions to the problem of electromagnetic wave propagation in inhomogeneous multilayered structures of arbitrarily varying thickness. To this end, we employ generalized transforms that provide an appropriate basis for the complete expansion of the transverse components of the electromagnetic fields. The continuous parts of the wavenumber spectrum are the radiation and the lateral wave terms while the discrete part is identified as the finite set of trapped waveguide modes (surface waves). When the bounding media are characterized by perfect electric or magnetic walls (μ/e → 0 or e/μ → 0, respectively) or surface impedances, the fields are expressed exclusively in terms of an infinite set of waveguide modes. These solutions are not restricted by the approximate surface impedance concept and the sources and observation point may be located in any of the nonuniform layers of the structure. Exact boundary conditions are imposed and the solutions satisfy the reciprocity relationships. Thus, the solutions are applicable to artificial layered structures as well as natural structures such as the inhomogeneous ionosphere and the earth's crust. These solutions can also be used to determine the scattering from objects of finite cross section in free space or embedded in the earth's crust.
Thermal Motion of DNA in an MspA Pore

We report on an experiment and calculations that determine the thermal motion of a voltage-clamped single-stranded DNA-NeutrAvidin complex in a Mycobacterium smegmatis porin A nanopore. The electric force and diffusion constant of DNA inside a Mycobacterium smegmatis porin A pore were determined to evaluate the thermal position fluctuations of DNA. We show that an out-of-equilibrium state returns to equilibrium so quickly that experiments usually measure a weighted average over the equilibrium position distribution. Averaging over the equilibrium position distribution is consistent with results of state-of-the-art nanopore sequencing experiments. It is shown how a reduction in thermal position fluctuations can be achieved by increasing the electrophoretic force used in nanopore sequencing devices.
Distinguishing between stellar and planetary companions with phase monitoring

Exoplanets which are detected using the radial velocity technique have a well-known ambiguity of their true mass, caused by the unknown inclination of the planetary orbit with respect to the plane of the sky. Constraints on the inclination are aided by astrometric follow-up in rare cases or, in ideal situations, through subsequent detection of a planetary transit. As the predicted inclination decreases, the mass of the companion increases leading to a change in the predicted properties. Here we investigate the changes in the mass, radius and atmospheric properties as the inclination pushes the companion from the planetary into the brown dwarf and finally low-mass star regimes. We determine the resulting detectable photometric signatures in the predicted phase variation as the companion changes properties and becomes self-luminous. We apply this to the HD 114762 and HD 162020 systems for which the minimum masses of the known companions place them at the deuterium-burning limit.
Plume-transform interactions at ultra-slow spreading ridges: Implications for the Southwest Indian Ridge

[1] We explore a potentially important variable in controlling ridge-hot spot interaction, the effect of transform offsets in limiting along-axis flow of plume material. We focus on the Southwest Indian Ridge (SWIR), where the “transform damming” effect is likely to be pronounced because of both long offset lengths and large contrasts in lithospheric thickness across the transform faults due to the ultra-slow spreading rate. We investigate the degree to which transform faults affect axial asthenospheric flow by performing a series of three-dimensional (3-D) numerical experiments with simplified channel-flow geometry and extrapolating their results to the SWIR. 3-D mantle viscosity structure for a ridge-transform-ridge system is determined based on temperature- and pressure-dependent viscosity laws. We consider six transform lengths, spanning 0 to 250 km in increments of 50 km. We then calculate the 3-D viscous flow in response to an along-axis pressure gradient corresponding to a ridge-centered hot spot. Modeling results predict that transform faults affect along-axis asthenospheric flow in two important ways. First, transforms reduce along-axis flux. The longer the transform offset, the greater the reduction in across-transform flux relative to the zero-offset case. Second, transforms deflect shallow asthenospheric along-axis flow. The predicted transform damming effect is most pronounced for a viscosity structure that is strictly pressure- and temperature-dependent. Flux reduction effects could be less significant for viscosity laws that additionally consider dehydration, melting, and change in deformation mechanism. This model predicts that the waist width of an on-axis plume is dependent not only on such previously explored factors as buoyancy and spreading rate, but also on the geometry of ridge segmentation. Along the SWIR, axial flow driven by the Marion plume is likely curtailed by the long-offset Andrew Bain and Discovery II fracture zones, severely limiting its lateral extent.
Characterizing branching processes from sampled data

Branching processes model the evolution of populations of agents that randomly generate offspring (children). These processes, more patently Galton-Watson processes, are widely used to model biological, social, cognitive, and technological phenomena, such as the diffusion of ideas, knowledge, chain letters, viruses, and the evolution of humans through their Y-chromosome DNA or mitochondrial RNA. A practical challenge of modeling real phenomena using a Galton-Watson process is the choice of the offspring distribution, which must be measured from the population. In most cases, however, directly measuring the offspring distribution is unrealistic due to lack of resources or the death of agents. So far, researchers have relied on informed guesses to guide their choice of offspring distribution. In this work we propose two methods to estimate the offspring distribution from real sampled data. Using a small sampled fraction of the agents and instrumented with the identity of the ancestors of the sampled agents, we show that accurate offspring distribution estimates can be obtained by sampling as little as 14% of the population.
Nonlinear Vector Filtering for Impulsive Noise Removal from Color Images

A comprehensive survey of 48 filters for impulsive noise removal from color images is presented. The filters are formulated using a uniform notation and categorized into 8 families. The performance of these filters is compared on a large set of images that cover a variety of domains using three effectiveness and one efficiency criteria. In order to ensure a fair efficiency comparison, a fast and accurate approximation for the inverse cosine function is introduced. In addition, commonly used distance measures (Minkowski, angular, and directional-distance) are analyzed and evaluated. Finally, suggestions are provided on how to choose a filter given certain requirements.
"Sell in May and Go Away" Just Won't Go Away

The authors performed an out-of-sample test of the sell-in-May effect documented in previous research. Reducing equity exposure starting in May and levering it up starting in November persists as a profitable market-timing strategy. On average, stock returns are about 10 percentage points higher for November–April half-year periods than for May–October half-year periods. The authors also found that the sell-in-May effect is pervasive in financial markets.
Have Welfare-to-Work Programs Improved over Time in Putting Welfare Recipients to Work?

The authors examine data from 21 random assignment evaluations of 76 experimental welfare-to-work programs conducted in the United States between 1983 and 1998 to determine whether the impacts of these programs on employment improved over time. Welfare-to-work programs have long played an important role in the federal assistance program known as Aid to Families with Dependent Children (AFDC) , now called Temporary Assistance to Needy Families (TANF). Over the 16-year period covered by the experiments, an increasing percentage of control group members received services similar to those offered to program group members. As a result, the differential participation in program service activities between the program and the control group decreased steadily over time, reducing the impact of these programs on employment. The negative influence of the reduced incremental services was nevertheless offset by other factors that resulted in program impacts remaining essentially constant during the study period. The authors suggest ways to improve program impacts in future experiments.
Unpacking the Concept of Complexity in Instructed SLA Research: Towards an Acquisitional Definition

Over the past few decades, the field of second language acquisition (SLA) has seen a remarkable increase of interest in the study of instructed second language acquisition (ISLA), which “investigates second language (L2) learning or acquisition that occurs as a result of teaching” (Loewen, 2014, p. 2). The importance of this subfield has particularly been emphasized for the sake of adult L2 learners, who, due to biological and cognitive constraints, have difficulty acquiring a target language (TL) solely based on naturalistic input (e.g., Han, 2004; Long, 1990). For this, ISLA research has suggested the utilization of focus on form (FonF), a pedagogical approach that attempts to engage learners’ metalinguistic attention in an otherwise solely meaning-based environment (Doughty & Williams, 1998; Long, 1991; Long & Robinson, 1998). According to Doughty and Williams (1998), FonF involves an array of pedagogical options, ranging from implicit techniques (e.g., input flood, input enhancement, and recasts) that attempt to attract leaners’ attention to form, to explicit techniques (e.g., processing instruction, consciousness-raising, and dictogloss) that attempt to direct their attention to form.
Bank Capital and Value in the Cross-Section

We develop a dynamic model of bank capital structure in an acquisitions context which predicts: (i) total bank value and the bank's equity capital are positively correlated in the cross-section, and (ii) the various components of bank value are also positively cross-sectionally related to bank capital. Our empirical tests provide strong support for these predictions. The results are robust to a variety of alternative explanations--growth prospects, desire to acquire toe-hold positions, desire of capital-starved acquirers to buy capital-rich targets, market timing, pecking order, the effect of banks with binding capital requirements, Too Big To Fail, target profitability, risk, and mechanical effects. The Author 2011. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org., Oxford University Press.
Risk aversion or risk management?: How measures of risk aversion affect firm entry and firm survival

The link between measured risk aversion and the decision to become an entrepreneur is well established, but the link between risk aversion and entrepreneurial success is not. Standard theoretical models of occupational choice under uncertainty imply a positive correlation between an individual’s degree of risk aversion and the expected return from an entrepreneurial venture at the time of entry. Because the expected return is the risk neutral equivalent value, a higher expected return implies a higher survival probability, and so more risk averse entrepreneurs should survive more frequently than their less risk averse counterparts. We test that prediction using successive entry cohorts of young entrepreneurs in the National Longitudinal Survey of Youth 1979 (NLSY79). The empirical results soundly reject the prediction: the most successful entrepreneurs are the least risk averse. This surprising finding calls into question the interpretation of common measures of risk aversion as measures of taste for risk. Instead, measured risk attitudes perform as if they are indicators of entrepreneurial ability– the least risk averse are apparently those who can best assess and manage risks. Indeed, our interpretation is consistent with the work of recent experimental studies that find that the less risk averse have higher cognitive ability.
Should U.S. and Global Regulators Take a Bigger Tax Bite Out of Technology Companies? A Case on Apple's International Tax Minimization and Reporting Strategies

ABSTRACT: This case provides students with an opportunity to examine the international tax minimization and reporting strategies of Apple Inc. (Apple) and other technology companies, as well as the...
Sex Assignment in the Neonate With Intersex or Inadequate Genitalia

Clinical decisions about the newborn with ambiguous genitalia should not be approached dogmatically. Data on the psychosexual and psychosocial outcomes of these children are quite simply lacking. Personal experience with 18 children who are 46,XY males with totally inadequate phalluses but normal testes, sex reassigned to female, demonstrates that parents tend to be uncomfortable with sex reassignment and that the children do not behave as typical little girls. Intersexual children present an equally distressing dilemma. Ongoing research should soon add valuable data, 1 which is insufficient at present. Nevertheless, a data-oriented approach is feasible, if necessarily tentative. Assigning a sex-of-rearing to an intersexual neonate must take 1 of 2 directions: treat or do not treat. Sociocultural norms and family demands are likely to push the parents into a treatment mode of thinking. My data implies that older children and young adolescents want cosmetically "appropriate" genitalia. Recognizing the need for a
Coherent analog FM-SCM video transmission using direct frequency modulation of semiconductor lasers

The advantages of analog subcarrier-multiplexed (SCM) FM video transmission using frequency modulation of the optical carrier over other analog laser modulation schemes include the reduced impact of laser relative intensity noise and the phase noise suppression achievable in a receiver employing FM demodulation of both the subcarrier and optical carrier. Way et al.1 detected these FM-FM signals using an erbium-doped fiber amplifier and an optical frequency discriminator followed by a direct-detection receiver. We examine the performance of a coherent receiver for the same use.
Conditions at the Downstream Boundary for Simulations of Viscous, Incompressible Flow

The proper specification of boundary conditions at artificial boundaries for the simulation of time-dependent fluid flows has long been a matter of controversy. In this work, the general theory of asymptotic boundary conditions for dissipative waves, developed in [T. Hagstrom, Math. Comp., submitted],is applied to the design of simple, accurate conditions at a downstream boundary for incompressible flows. For Reynolds numbers far enough below the critical value for linear stability, a scaling is introduced which greatly simplifies the construction of the asymptotic conditions. Numerical experiments with the nonlinear dynamics of vortical disturbances to plane Poiseuille flow are presented which illustrate the accuracy of our approach for low to moderate Reynolds numbers. The consequences of directly applying the scalings to the equations are also considered.
CHERN-SIMONS DUALITY AND THE QUANTUM HALL EFFECT

In previous work on the quantum Hall effect on an annulus, we used O(d, d; Z) duality transformations on the action describing edge excitations to generate the Haldane hierarchy of Hall conductivities. Here we generate the corresponding hierarchy of “bulk actions” which are associated with Chern-Simons (CS) theories, the connection between the bulk and edge arising from the requirement of anomaly cancellation. We also find a duality transformation for the CS theory exactly analogous to the duality of the scalar field theory at the edge.
Has fiscal policy helped stabilize the postwar U.S. economy

Abstract In this paper, I consider whether postwar fiscal policy has helped stabilize the U.S. economy. I do this by adding to the stochastic growth model fiscal policy feedback rules estimated from postwar data. These rules allow fiscal policies to respond to current and lagged output and labor hours. I use the estimated policy rules to see if postwar fiscal policy reduces output volatility and/or lengthens expansions and shortens recessions. I find that fiscal policy in general provides little stability on either count. I also find that the endogenous feedback links, by themselves, can provide some stabilization.
Ellipsoids of maximal volume in convex bodies

The largest discs contained in a regular tetrahedron lie in its faces. The proof is closely related to the theorem of Fritz John characterizing ellipsoids of maximal volume contained in convex bodies.
Maps between moduli spaces of vector bundles and the base locus of the theta divisor

We consider maps between different spaces of vector bundles on curves obtained by taking wedge powers, elementary transformations or kernels of evaluation maps and studying their respective fibers. We apply the results to construct large dimensional sets in the base locus of the generalized theta divisor.
[Ne II] Observations of Gas Motions in Compact and Ultracompact H II Regions

We present high spatial and spectral resolution observations of 16 Galactic compact and ultracompact H II regions in the [Ne II] 12.8 μm fine-structure line. The small thermal width of the neon line and the high dynamic range of the maps provide an unprecedented view of the kinematics of compact and ultracompact H II regions. These observations solidify an emerging picture of the structure of ultracompact H II regions suggested in our earlier studies of G29.96–0.02 and Mon R2 IRS 1; systematic surface flows, rather than turbulence or bulk expansion, dominate the gas motions in the H II regions. The observations show that almost all of the sources have significant (5-20 km s−1) velocity gradients and that most of the sources are limb-brightened. In many cases, the velocity pattern implies tangential flow along a dense shell of ionized gas. None of the observed sources clearly fits into the categories of filled expanding spheres, expanding shells, filled blister flows, or cometary H II regions formed by rapidly moving stars. Instead, the kinematics and morphologies of most of the sources lead to a picture of H II regions confined to the edges of cavities created by stellar wind ram pressure and flowing along the cavity surfaces. In sources where the radio continuum and [Ne II] morphologies agree, the majority of the ionic emission is blueshifted relative to nearby molecular gas. This is consistent with sources lying on the near side of their natal clouds being less affected by extinction and with gas motions being predominantly outward, as is expected for pressure-driven flows.
Interactions of silicate ions with zinc(II) and aluminum(III) in alkaline aqueous solution.

Al, and 67 Zn NMR evidence to show that silicate ions in alkaline solution form complexes with zinc(II) (present as zincate, Zn(OH) 3 - or Zn(OH)4 2- ) and, concomitantly, with aluminate (Al(OH)4 - ). Zincate reacts with monomeric silicate at pH 14-15 to form ((HO)O2Si-O-Zn(OH)3) 4- and with dimeric silicate to produce (HO-SiO2-O-SiO2-O-Zn(OH)3) 6- . The exchange of Si between these free and Zn-bound sites is immeasurably fast on the 29 Si NMR time scale. The cyclic silicate trimer reacts relatively slowly and incompletely with zincate to form ((HO) 3Zn{(SiO3)3}) 7- . The concentration of the cyclic trimer becomes further depleted because zincate scavenges the silicate monomer and dimer, with which the cyclic trimer is in equilibrium on the time scale of sample preparation. Identification of these zincate -silicate complexes is supported by quantum chemical theoretical calculations. Aluminate and zincate, when present together, compete roughly equally for a deficiency of silicate to form ((HO) 3ZnOSiO2OH) 4- and ((HO)3AlOSiO2OH) 3- which exchange 29 Si at a fast but measurable rate.
1H-Pyrazole-1-carboxamidines: new inhibitors of nitric oxide synthase

1H-Pyrazole-1-carboxamidines were prepared as potential inhibitors of the three isozymes of nitric oxide synthase. All of the compounds were found to be competitive inhibitors of all three isoforms. The most selective compound prepared was 1H-pyrazole-N-(3-aminomethylanilino)-1-carboxamidine (14), which is 100-fold selective for nNOS over eNOS with a Ki value of 2 microM.
Constructing packings in grassmannian manifolds via alternating projection

This paper describes a numerical method for finding good packings in Grassmannian manifolds equipped with various metrics. This investigation also encompasses packing in projective spaces. In each case, producing a good packing is equivalent to constructing a matrix that has certain structural and spectral properties. By alternately enforcing the structural condition and then the spectral condition, it is often possible to reach a matrix that satisfies both. One may then extract a packing from this matrix. This approach is both powerful and versatile. In cases in which experiments have been performed, the alternating projection method yields packings that compete with the best packings recorded. It also extends to problems that have not been studied numerically. For example, it can be used to produce packings of subspaces in real and complex Grassmannian spaces equipped with the Fubini–Study distance; these packings are valuable in wireless communications. One can prove that some of the novel configuratio...
Routing-aware scan chain ordering

Scan chain insertion can have a large impact on routability, wirelength, and timing of the design. We present a routing-driven methodology for scan chain ordering with minimum wirelength objective. A routing-based approach to scan chain ordering, while potentially more accurate, can result in TSP (Traveling Salesman Problem) instances which are asymmetric and highly nonmetric; this may require a careful choice of solvers. We evaluate our new methodology on recent industry place-and-route blocks with 1200 to 5000 scan cells. We show substantial wirelength reductions for the routing-based flow versus the traditional placement-based flow. In a number of our test cases, over 86p of scan routing overhead is saved. Even though our experiments are, so far, timing oblivious, the routing-based flow also improves evaluated timing, and practical timing-driven extensions appear feasible.
Non-Gaussianity in Two-Field Inflation

We derive semianalytic formulas for the local bispectrum and trispectrum from general two-field inflation and provide a simple geometric recipe for building observationally allowed models with large non-Gaussianity. We use the $\ensuremath{\delta}N$ formalism to express the bispectrum in terms of spectral observables and the transfer functions, which encode the superhorizon evolution of modes. Similarly, we calculate the trispectrum and show that the trispectrum parameter ${\ensuremath{\tau}}_{\mathrm{NL}}$ can be expressed entirely in terms of spectral observables, which provides a new consistency relation for two-field inflation. To generate observably large non-Gaussianity during inflation, we show that the sourcing of curvature modes by isocurvature modes must be extremely sensitive to a change in the initial conditions orthogonal to the inflaton trajectory and that the amount of sourcing must be nonzero. Under some minimal assumptions, we argue that the first condition is satisfied only when neighboring trajectories in the two-dimensional field space diverge during inflation. Geometrically, this means that the inflaton must roll along a ridge in the potential $V$ for some time during inflation and that its trajectory must turn somewhat in field space. Therefore, it follows that under our assumptions, two-field scenarios with attractor solutions necessarily produce small non-Gaussianity. This explains why it has been so difficult to achieve large non-Gaussianity in two-field inflation and why it has only been achieved in a small fraction of models where the potential and/or the initial conditions are fine-tuned. Some of our conclusions generalize at least qualitatively to multifield inflation and to scenarios where the interplay between curvature and isocurvature modes can be represented by the transfer function formalism.
Degree Distribution of Competition-Induced Preferential Attachment Graphs

We introduce a family of one-dimensional geometric growth models, constructed iteratively by locally optimizing the trade-offs between two competing metrics, and show that this family is equivalent to a family of preferential attachment random graph models with upper cut-offs. This is the first explanation of how preferential attachment can arise from a more basic underlying mechanism of local competition. We rigorously determine the degree distribution for the family of random graph models, showing that it obeys a power law up to a finite threshold and decays exponentially above this threshold.We also rigorously analyse a generalized version of our graph process, with two natural parameters, one corresponding to the cut-off and the other a ‘fertility’ parameter. We prove that the general model has a power-law degree distribution up to a cut-off, and establish monotonicity of the power as a function of the two parameters. Limiting cases of the general model include the standard preferential attachment model without cut-off and the uniform attachment model.
Reflection implies the SCH

We prove that, e.g., if mu >cf(mu)= aleph_0 and mu>2^{aleph_0} and every stationary family of countable subsets of mu^+ reflect in some subset of mu^+ of cardinality aleph_1, then the SCH for mu^+ (moreover, for mu^+, any scale for mu^+ has a bad stationary set of cofinality aleph_1). This answers a question of Foreman and Todorcevic who got such conclusion from the simultaneous reflection of four stationary sets.
Exact relation between Einstein and quadratic quantum gravity

Abstract We show the exact equality of the path integral of the general renormalizable fourth order gravitational action to the path integral of the Einstein action coupled to a massive spin-0 field and a massive spin-2 ghost-like field with non-polynomial interactions. The metric in the Einstein version is a highly nonlinear function of the metric in the quadratic version. Both massive excitations are unstable. The respective cosmological constant terms in the two versions can be very different. Some implications are briefly discussed.
Thiophenol promoted cyclization of enynes

Abstract Vinyl radicals generated by the addition of thiophenol to enynes have been shown to cyclize regioselectively giving cyclohexylidene thioethers.
Joint source/channel coding for multiple images

A joint source/channel coding algorithm is proposed for the transmission of multiple image sources over memoryless channels. The proposed algorithm uses a quality scalable image coder to optimally allocate a limited bit budget among all the sources to achieve the optimal overall distortion reduction for the multiple reconstructed images. In addition to the conventional un gain, it provides channel multiplexing gain, which can be much more significant. Furthermore, an extended scheme is proposed to provide flexibility between the optimization performance and complexity.
Specifying intonation from context for speech synthesis

Abstract This paper presents a theory and a computational implementation for generating prosodically appropriate synthetic speech in response to database queries. Proper distinctions of contrast and emphasis are expressed in an intonation contour that is synthesized by rule under the control of a grammar, a discourse model and a knowledge base. The theory is based on Combinatory Categorial Grammar, a formalism which easily integrates the notions of syntactic constituency, semantics, prosodic phrasing and information structure. Results from our current implementation demonstrate the system's ability to generate a variety of intonational possibilities for a given sentence depending on the discourse context.
Clinical Imaging with Transmissive Ultrasonic Computerized Tomography

Transmission ultrasound computer-assisted tomography has been developed for detection and diagnosis of cancer in the breast. Pulses of ultrasound (8 MHz ±3 MHz) are transmitted through the breast in a coronal plane from a plurality of directions. The received signal is processed for arrival time and for changes in amplitude. The measured values for arrival time and attenuation are used in a convolution-back projection reconstruction algorithm to obtain estimates of the two-dimensional distribution of acoustic speed and attenuation within the scanned planes of the breast. Over 1000 images in breasts of approximately 150 patients have been scanned of whom 30 had biopsy proven cancer. Some common characteristics of the reconstructed images which are associated with cancer are 1) increased speed relative to the embedding tissue associated with 2) decreased attenuation in central region of the lesion usually with 3) a ring of higher attenuation at the border of the lesion. Current estimates of sensitivity and specificity of this system for cancer are approaching those of X-ray mammography techniques.
THE SUPERNOVA IMPOSTOR IMPOSTOR SN 1961V: SPITZER SHOWS THAT ZWICKY WAS RIGHT (AGAIN)

SN 1961V, one of Zwicky's defining Type V supernovae (SNe), was a peculiar transient in NGC 1058 that has variously been categorized as either a true core-collapse SN leaving a black hole (BH) or neutron star (NS) remnant, or an eruption of a luminous blue variable star. The former case is suggested by its possible association with a decaying non-thermal radio source, while the latter is suggested by its peculiar transient light curve and its low initial expansion velocities. The crucial difference is that the star survives a transient eruption but not an SN. All stars identified as possible survivors are significantly fainter, L{sub opt} {approx} 10{sup 5} L{sub sun}, than the L{sub opt} {approx_equal} 3 x 10{sup 6} L{sub sun} progenitor star at optical wavelengths. While this can be explained by dust absorption in a shell of material ejected during the transient, the survivor must then be present as an L{sub IR} {approx_equal} 3 x 10{sup 6} L{sub sun} mid-infrared source. Using archival Spitzer observations of the region, we show that such a luminous mid-IR source is not present. The brightest source of dust emission is only L{sub IR} {approx_equal} 10{sup 5} L{sub sun} and does not correspond tomore » the previously identified candidates for the surviving star. The dust cannot be made sufficiently distant and cold to avoid detection unless the ejection energy, mass, and velocity scales are those of an SN or greater. We conclude that SN 1961V was a peculiar, but real, SN. Its peculiarities are probably due to enhanced mass loss just prior to the SN, followed by the interactions of the SN blast wave with this ejecta. This adds to the evidence that there is a population of SN progenitors that have major mass-loss episodes shortly before core collapse. The progenitor is a low metallicity, {approx}1/3 solar, high-mass, M{sub ZAMS} {approx}> 80 M{sub sun}, star, which means either that BH formation can be accompanied by an SN or that surprisingly high-mass stars can form an NS. We also report on the mid-IR properties of the two other SNe in NGC 1058, SN 1969L, and SN 2007gr.« less
Not it: opting out of voluntary coalitions that provide a public good

Most coalitions that form to increase contributions to a public good do not require full participation by all users of the public good, and therefore create incentives for free riding. If given the opportunity to opt out of a voluntary coalition, in theory, agents should try to be among the first to do so, forcing the remaining undecided agents to bear the cost of participating in the coalition. This study tests the predicted sequence of participation decisions in voluntary coalitions using real-time threshold public goods experiments. We find that subjects’ behavior is more consistent with the theoretical predictions when the difference in payoffs between coalition members and free-riding non-members is relatively large.
Modular centralizer algebras corresponding to p-groups

Abstract We study the Loewy structure of the centralizer algebra k P Q for P a p-group with subgroup Q and k a field of characteristic p. Here k P Q is a special type of Hecke algebra. The main tool we employ is the decomposition k P Q = k C P ( Q ) ⋉ I of k P Q as a split extension of a nilpotent ideal I by the group algebra k C P ( Q ) . We compute the Loewy structure for several classes of groups, investigate the symmetry of the Loewy series, and give upper and lower bounds on the Loewy length of k P Q . Several of these results were discovered through the use of MAGMA, especially the general pattern for most of our computations. As a final application of the decomposition, we determine the representation type of k P Q .
Conformal predictions in multimedia pattern recognition

The field of multimedia pattern recognition is on a fundamental quest to design intelligent systems that can learn and behave the way humans do. One important aspect of human intelligence that has so far not been given sufficient attention in these fields is the capability of humans to hedge decisions. Humans can express when they are certain about a decision they have made, and when they are not. Unfortunately, machine learning techniques today are not yet fully equipped to be trusted with this critical task. This work seeks to address this fundamental knowledge gap. Existing approaches that provide a measure of confidence of a learning algorithm on a prediction such as those based on the Bayesian theory or the Probably Approximately Correct learning theory require strong assumptions or often produce results that are not practical or reliable. However, the recently developed Conformal Predictions (CP) framework - which is based on the principles of hypothesis testing, transductive inference and algorithmic randomness - provides a game-theoretic approach to the estimation of confidence with several desirable properties such as online calibration and generalizability to all classification and regression methods.
Regularising 3D data using Fourier reconstruction and sparse inversion

A-015 REGULARISING 3D DATA USING FOURIER RECONSTRUCTION AND SPARSE INVERSION P. M. ZWARTJES and C. O. H. HINDRIKS Delft University of Technology Lab. of Acoustic Imaging and Sound Control PO Box 5046 2600 GA Delft The Netherlands Abstract Fourier reconstruction yields a better regularisation than can be obtained by a simple binning procedure. The method consists of estimating the Fourier coefficients by least-squares inversion with a priori information. The sparse distribution of energy over the Fourier coefficients can be used as a priori information. Resulting algorithms perform significantly better in a 3D synthetic experiment than conventional Fourier reconstruction with a
Parametric Study of Zinc Deposition on Porous Carbon in a Flowing Electrolyte Cell

X‐ray radiography coupled with high resolution optical densitometry, as well as optical and scanning electron microscopy, was employed to study the effect of pivotal zinc deposition parameters on the zinc morphology within a porous C foam electrode. Deposition was carried out in zinc‐bromine and zinc‐zinc cells with circulating electrolyte. Results on the effects of flow rate, substrate thickness, current density, and electrolyte composition on zinc distribution in the substrate and on its surface are described. This study has shown that in the absence of organic inhibitors, very nonuniform zinc deposition occurs within the porous electrode. This zinc deposition corresponds to the nonuniform primary current distribution dominated by ohmic resistance. This study has led to the conclusions that high electrolyte flow rates, moderate current densities, and thick foams all aid in producing increasingly uniform zinc deposits. The most beneficial effects on the zinc morphology, however, were obtained by adding to the electrolyte a dendrite inhibitor‐solubilizer combination consisting of certain fluorosurfactants and butyrolactone.
An Analysis of Farmers' Agricultural Policy Preferences

This paper analyzes farmers' attitudes toward competing agricultural policies. The empirical work utilizes data on Iowa farmers' opinions of four policies: continuing the current program, targeting benefits to fiscally stressed farmers, mandatory controls, and decoupling. The results show that a farmer's financial situation, size and type of operation, education, and farm experience significantly influence his opinions. Attitudes toward mandatory controls and targeting are most sensitive, and attitudes toward continuation of the current program are least sensitive to changes in economic characteristics. Strong identifiable camps of both support and opposition are found for each policy except the current program.
Mechanical design issues in laterally-driven microstructures

Abstract The mechanical issues influencing the design and performance of laterally-driven resonant-structure micromechanical systems are identified and quantified. Two forms of resonant-structure suspensions are presented and the performance of each is calculated and compared. One represents tension-generating flexure, while the second, a ‘crab-leg’ flexure, utilizes motion-generated bending of the suspension. This second device is an unusual case of lateral motion (parallel to the substrate) with suspension elements subjected to lateral bending. The limit of linear motion (magnitude of motion subject to a constant flexural spring rate) is determined and a stress analysis is performed. An optimal design theory for each flexure is developed in which the objective is to obtain the greatest deflection per unit of allowable material stress. Preliminary results indicate that the inclusion of special design details can generate a two-to-one decrease in stress for a given level of displacement. In accordance with this optimal design theory, a prototype ‘crab-leg’ flexure is fabricated with a stress-to-displacement ratio calculated to be as low as 65 MPa/μm.
Waveguide loss measurement using photothermal deflection

Presentation d'une methode de mesure des pertes de propagation dans les guides d'ondes basee sur l'effet de deflexion photothermique
Facile installation of the phosphonate and (α,α-difluoromethyl)phosphonate functionalities equipped with benzyl protection

Abstract Under appropriate conditions, dibenzyl (lithiomethyl)phosphonate and dibenzyl (lithiodifluoromethyl)phosphonate displace primary triflates to provide convenient access to the corresponding phosphonates, carrying benzyl ester protecting groups. This approach is of particular advantage for phosphonate ester deprotection, which may be achieved by simple hydrogenolysis.
Accounting Choice and Earnings Quality: The Case of Software Development

In this study I explore how accounting choice affects earnings quality in the software development industry. SFAS No. 86, which requires capitalization of software development costs (SDC), is the only exception in the US to SFAS No. 2, which requires immediate expensing of all research and development (R&D) expenditures. Aboody and Lev (1998) suggest that capitalized SDC are value-relevant. Thus, expensing of these costs might introduce noise into earnings. However, it has been suggested that future benefits associated with SDC are highly uncertain (Software Publishers Association). Consequently, capitalization might introduce noise into earnings by capitalizing unproductive expenditures. Hence, it is not clear how managers' choice between capitalization and expensing will affect earnings quality. I first find that there is a decline in the quality of earnings in the software industry after the adoption of SFAS No. 86, whereas no such decline is observed in other high-tech industries. Second, I find that,...
Core Needle Biopsy Versus Fine Needle Aspiration Biopsy: Are There Similar Sampling and Diagnostic Issues?

Evidence suggests that in experienced hands fine needle aspiration biopsy (FNAB) is highly safe and effective for the evaluation of patients who have palpable breast lesions. In most cases, FNAB leads to an appropriate clinical or surgical management. FNAB can also be effectively used in evaluation of cystic lesions under ultrasound guidance. Other nonpalpable lesions can benefit from image-directed core needle biopsy (CNB). Overall, cost should influence the decision to use FNAB or CNB. FNAB may be the only affordable procedure in developing countries. Breast cancer affects significant numbers of women worldwide. Attempts should be made to take all the measures necessary to consider optimal approaches to breast health care for everyone regardless of age, race, ethnicity, or social status.
Cobalt(III)-catalyzed synthesis of indazoles and furans by C-H bond functionalization/addition/cyclization cascades.

The development of operationally straightforward and cost-effective routes for the assembly of heterocycles from simple inputs is important for many scientific endeavors, including pharmaceutical, agrochemical, and materials research. In this article we describe the development of a new air-stable cationic Co(III) catalyst for convergent, one-step benchtop syntheses of N-aryl-2H-indazoles and furans by C–H bond additions to aldehydes followed by in situ cyclization and aromatization. Only a substoichiometric amount of AcOH is required as an additive that is both low-cost and convenient to handle. The syntheses of these heterocycles are the first examples of Co(III)-catalyzed additions to aldehydes, and reactions are demonstrated for a variety of aromatic, heteroaromatic, and aliphatic derivatives. The syntheses of both N-aryl-2H-indazoles and furans have been performed on 20 mmol scales and should be readily applicable to larger scales. The reported heterocycle syntheses also demonstrate the use of direct...
Turbulent premixed flame propagation models for different combustion regimes

Conceptual models of turbulent premixed flame propagation speeds for the three combustion regimes have been proposed and tested by comparing to the available well-defined data obtained on a variety of experimental rigs. The model for the wrinkled flame regime has been based on the Tennekes and Kuo-Corrsin concept of isotropic turbulence which proposes that dissipative eddies are most probably consist of vortex tubes with a diameter of the order of Kolmogorow scale and a spacing of the order of the Taylor length scale. Using this concept of turbulence structure, it was shown that the normalized turbulent flame propagation speed, ut/ul, is proportional to the square root of the normalized turbulence intensity, u′/ul and the turbulent Reynolds number based on Kolmogorov length scale. Rn. In the intermediate regime, assuming that the effective flame front surface area grows exponentially with the turbulence intensity, ut/ul. is linearly dependent on Rν and exponentially dependent on the square root of u′/ul. In the distributed reaction zones regime, starting with the Damkohler's formulation, dimensionless numbers contributing to the flame propagation have been selected, and it was found that ut/u′ is proportional to the 3/4th power of ul/u′. Comparison of the predictions of the models and the experimental data from a variety of rigs shows excellent agreement despite the uncertainties involved in the measurement of the turbulence parameters and propagation velocities.
The gravitational field of a radiating electromagnetic dipole

The principle purpose of this paper is to analyze in the context of general relativity the effects of electromagnetic radiation on a gravitational field. The basic outline is that we start from flat-space with a time-dependent electric and magnetic dipole solution of Maxwell's equations. This field, treated as first order, then acts as the source for a gravitational perturbation. First, from the flat-space version of the Bianchi identities, with the Maxwell stress tensor as the (second-order) source, the Weyl tensor is found as a field on the Minkowski background. From this Weyl tensor, we go on and find the spin coefficients and the full metric in this second-order approximation. The physical interpretation and meaning of many of the derived relations are discussed. In particular, we can identify the Bondi energy?momentum?given in terms of the Maxwell field?and their evolution. Of particular attractiveness is the observation of an angular momentum conservation law that comes directly from the asymptotic terms in the Bianchi identities. This law contains a flux term that is a confirmation of a classical E&M result but obtained directly from GR.
R-matrix Poisson algebras and their deformations

We classify in this paper Poisson structures on modules over semisimple Lie algebras arising from classical r-matrices. We then study their quantizations and the relation to classical invariant theory
Mid Pouch Strictureplasty for Crohn's Disease After Ileal Pouch-Anal Anastomosis: An Alternative to Pouch Excision

A 33-year-old female developed an isolated stricture of the mid portion of her ileal pouch nine years after proctocolectomy and J-ileal pouch-anal anastomosis for ulcerative colitis. Repeated episodes of pouchitis and partial small-bowel obstruction led to pouchoscopy and pouchography, which demonstrated pouch inflammation and a long, tight, midpouch stricture. Her diagnosis was changed to Crohn's disease and she was treated with azathioprine, budesonide, and infliximab. Repeat pouchoscopy demonstrated mucosal healing but a persistent fibrotic stricture. Pouch reconstruction was performed with a midpouch strictureplasty alleviating her obstructive symptoms. One year after surgery, the patient has no clinical evidence of obstruction and repeat pouchography demonstrates a wider pouch lumen across the strictureplasty site. Strictureplasty is an alternative to pouch excision in the management of patients with Crohn's disease who have an isolated pouch stricture.
An Investigation of Why Taxpayers Prefer Refunds: A Theory of Planned Behavior Approach

Approximately 80 percent of individual tax returns filed with the IRS result in refunds. According to 2003 Statistics of Income data, these refunds average approximately $2,400. In effect, over‐withholding of federal income taxes results in interest‐free loans to the government, creating opportunity costs to taxpayers equal to the amount of forgone interest income. This study examines the underlying reasons why taxpayers tend to make tax payments that ultimately result in a tax refund. We draw on Ajzen's (1991) Theory of Planned Behavior to comprehensively model this phenomenon. Overall, the results from 140 respondents show taxpayers' attitudes (e.g., desire to avoid uncertainty or to avoid any chance of underpayment) and subjective norms (e.g., perceptions of friends' likely advice) affect their withholding decisions. Although respondents understand that they are forgoing investment income and perceive that they could change their withholding with relative ease, they are still hesitant to reduce their o...