cssi/SciSciGPT-SciSciNet huggingface dataset:
A turnstile mechanism for fronts propagating in fluid flows

We consider the propagation of fronts in a periodically driven flowing medium. It is shown that the progress of fronts in these systems may be mediated by a turnstile mechanism akin to that found in chaotic advection. We first define the modified (“active”) turnstile lobes according to the evolution of point sources across a transport boundary. We then show that the lobe boundaries may be constructed from stable and unstable burning invariant manifolds (BIMs)—one-way barriers to front propagation analogous to traditional invariant manifolds for passive advection. Because the BIMs are one-dimensional curves in a three-dimensional (xyθ) phase space, their projection into xy-space exhibits several key differences from their advective counterparts: (lobe) areas are not preserved, BIMs may self-intersect, and an intersection between stable and unstable BIMs does not map to another such intersection. These differences must be accommodated in the correct construction of the new turnstile. As an application, we consider a lobe-based treatment protocol for protecting an ocean bay from an invading algae bloom.
Transition metal–carbon multiple bonds

Since the discovery of the first example of a transition metal carbene complex 37 years ago, and a transition metal carbyne complex a few years later, investigations into the chemistry of compounds that contain multiple metal–carbon bonds have continued steadily. Many compounds that contain multiple metal–carbon bonds are now established as catalysts or stoichiometric reagents in organic chemistry. In this perspective, important steps in the development of transition metal–carbon multiple bond chemistry, in particular chemistry in which the metal is in it's highest possible oxidation state, are highlighted, and possible avenues for further advances are suggested.
Enantioselective Heck Arylations of Acyclic Alkenyl Alcohols Using a Redox-Relay Strategy

Progress in the development of asymmetric Heck couplings of arenes and acyclic olefins has been limited by a tenuous understanding of the factors that dictate selectivity in migratory insertion and β-hydride elimination. On the basis of key mechanistic insight recently garnered in the exploration of selective Heck reactions, we report here an enantioselective variant that delivers β-, γ-, or δ-aryl carbonyl products from acyclic alkenol substrates. The catalyst system imparts notable regioselectivity during migratory insertion and promotes the migration of the alkene's unsaturation toward the alcohol to ultimately form the ketone product. The reaction uses aryldiazonium salts as the arene source, yields enantiomeric products from opposite starting alkene configurations, and uses a readily accessible ligand. The racemic nature of the alkenol substrate does not bias the enantioselection.
Stereoselective 1,3-insertions of rhodium(II) azavinyl carbenes.

Rhodium(II) azavinyl carbenes, conveniently generated from 1-sulfonyl-1,2,3-triazoles, undergo a facile, mild, and convergent formal 1,3-insertion into N–H and O–H bonds of primary and secondary amides, various alcohols, and carboxylic acids to afford a wide range of vicinally bisfunctionalized (Z)-olefins with perfect regio- and stereoselectivity. Utilizing the distinctive functionality installed through these reactions, a number of subsequent rearrangements and cyclizations expand the repertoire of valuable organic building blocks constructed by reactions of transition-metal carbene complexes, including α-allenyl ketones and amino-substituted heterocycles.
High-temperature polymorph of In2La

Abstract A polymorph of In 2 La was discovered by observing a change in the quadrupole interaction at nuclei of 111 In/Cd probe atoms at high temperature using the technique of perturbed angular correlation of gamma rays. Point-symmetry information from the measured electric field gradient and chemical considerations suggests that the high-temperature polymorph has the hexagonal AlB 2 structure. The transformation between the low-temperature phase, which has the CeCu 2 structure, and the high-temperature phase takes place with hysteresis over a temperature range from 200 to 450 °C.
The effects of price- and output-stabilising policies in an interdependent world economy

This paper represents an empirical investigation of the linkages among a set of “large” macroeconomies and individual “small” macroeconomies. Models of the “large” economies are estimated, allowing for asymmetric interdependence of their endogenous variables upon each other. Optimal policy problems are solved in a finite-horizon linear-quadratic framework. A set of “small” macroeconomies is designated, and models of those small economies are estimated which take explicit account of the large economies' state variables. A pair of optimal policy problems is then solved for each of the small economies — one in which the historical values of the large countries' state variables are exogenous to the small country, and a second in which the exogenous values are those generated as optimal trajectories in the large countries' policy problems. The relative stability of the small economies' endogenous variables is evaluated.
Performance of the Brookhaven photocathode rf gun

Abstract The Brookhaven Accelerator Test Facility (ATF) uses a photocathode rf gun to provide a high-brightness electron beam intended for FEL and laser acceleration experiments. The rf gun consists of 1 1 2 cells driven at 2856 MHz in π-mode with a maximum cathode field of 100 MV/m. To achieve long lifetimes, our photocathode development concentrates on robust metals such as copper, yttrium and samarium. We illuminate these cathodes with a 10 ps, frequency-quadrupled Nd: YAG laser. We describe the initial operation of the gun, including measurements of transverse and longitudinal emittance, quantum efficiencies, and peak current. These results are compared to models.
A Four-Country Study of the Associations Between Bribery and Unethical Actions

The purpose of this research is to extend prior research testing the premise that small deviations from ethical behavior lead to even larger deviations from ethical behavior. This study examines the association between a person’s willingness to bribe a police officer to avoid being issued a speeding ticket with their views on inappropriate behavior of corporate executives. Our sample of 528 participants comes from Colombia (90), Ecuador (70), South Africa (131) and the United States (237). As part of our data gathering, we controlled for social desirability response bias in the responses of the students who participated in our study. Our data indicate significant differences between the views of the students from Colombia, Ecuador, and South Africa when compared to the views of the students from the United States. The analysis indicates that, for all four dilemmas, the most significant variable was the belief about how ethical it was to pay a bribe to avoid a traffic ticket. In addition, in three of our four dilemmas, Paulhus’ Impression Management Subscale, which measures social desirability response bias, was the second most significant variable. Finally, in three of the four dilemmas, the students from Colombia, Ecuador and South Africa thought the actions described in the dilemmas were less ethical than the students from the United States.
Extending the Model of KH 15D: Estimating the Effects of Forward Scattering and Curvature of the Occulting Ring Edge

The periodic eclipses of the pre-main-sequence binary KH 15D have been explained by a circumbinary dust ring inclined to the orbital plane, which causes occultations of the stars as they pass behind the ring edge. We compute the extinction and forward scattering of light by the edge of the dust ring in order to explain (1) the gradual slope directly preceding total eclipse, (2) the gradual decline at the end of ingress, and (3) the slight rise in flux at mideclipse. The size of the forward-scattering halo indicates that the dust grains have a radius of a ~ 6(D/3 AU) μm, where D is the distance of the edge of the ring from the system barycenter. This dust size estimate agrees well with estimates of the dust grain size from polarimetry, adding to the evidence that the ring lies at several AU. Finally, the ratio of the fluxes during an eclipse to those not during an eclipse independently indicates that the ring lies at a few AU.
On C*-Extreme Maps and *-Homomorphisms of a Commutative C*-Algebra

The generalized state space of a commutative C*-algebra, denoted \(S_{{\mathcal{H}}}(C(X))\), is the set of positive unital maps from C(X) to the algebra \({\mathcal{B}}({\mathcal{H}})\) of bounded linear operators on a Hilbert space \({\mathcal{H}}\). C*-convexity is one of several non-commutative analogs of convexity which have been discussed in this context. In this paper we show that a C*-extreme point of \(S_{{\mathcal{H}}}(C(X))\) satisfies a certain spectral condition on the operators in the range of the associated positive operator-valued measure. This result enables us to show that C*-extreme maps from C(X) into \({\mathcal{K}}^{+}\), the algebra generated by the compact and scalar operators, are multiplicative. This generalizes a result of D. Farenick and P. Morenz. We then determine the structure of these maps.
Ambient occlusion volumes

Figure 1: 1.4 M-triangle scene at 720p resolution on GeForce 280 GT using geometry from Marvel Ultimate Alliance 2 by Vicarious Visions/Activision. The new Ambient Occlusion Volume algorithm produces quality comparable to ray tracing, in real time and with no noise. In contrast, many alternative screen-space algorithms offer extremely fast AO approximations but cannot converge towards the correct result, even when extended to high sampling rates as shown here.
Numerical studies of the vibrational isocoordinate rule in chalcogenide glasses

Many properties of alloyed chalcogenide glasses can be closely correlated with the average coordination of these compounds. This is the case, for example, of the ultrasonic constants, dilatometric softening temperature and the vibrational densities of states. What is striking, however, is that, at a given average coordination, these properties are nevertheless almost independent of the elemental composition. Here, we report on some numerical verification of this experimental rule as applied to the vibrational density of states. We find that this rule is not exact but holds qualitatively well over a wide range of compositions and local chemical correlations.
Free energy of alternating two-component polymer brushes on cylindrical templates

We use computer simulations to investigate the stability of a two-component polymer brush de-mixing on a curved template into phases of different morphological properties. It has been previously shown via molecular dynamics simulations that immiscible chains having different length and anchored to a cylindrical template will phase separate into stripes of different widths oriented perpendicularly to the cylindrical axis. We calculate free energy differences for a variety of stripe widths, and extract simple relationships between the sizes of the two polymers, N1 and N2, and the free energy dependence on the stripe width. We explain these relationships using simple physical arguments based upon previous theoretical work on the free energy of polymer brushes.
Why Service and Manufacturing Entry Mode Choices Differ: The Influence of Transaction Cost Factors, Risk and Trust*

ABSTRACT In this study, we suggest that disparities between service and manufacturing firms’ international entry mode choices can be explained by differences in their reaction to transaction cost based variables and by the influence of risk and trust propensity. We find that: (1) due to the investment intensive nature of manufacturing, environmental uncertainties and risk propensity influence manufacturers’ mode choices; while (2) behavioural uncertainties, trust propensity and asset specificity influence service providers’ entry mode choices because of the people-intensive nature of services. Implications for future research are discussed.
A new geometrical form of silicon. Synthesis and structure of tetraethylammonium bis(1,2-benzenediolato)fluorosilicate(IV)

Abstract Anionic pentacoordinated silicon compounds,1 isoelectronic with phosphoranes, are extremely rare. Of those synthesized, X-ray structural characterization of a spirocyclic derivative [(C6H4O2)2SiPh]-Me4N+ (1) has been reported2 and reveals a trigonal-bipyramidal form displaced about one-third the way toward a square pyramid.
Analytical methods of research into terminal area air traffic operations

The application of mathematical models of various suboperations in the terminal area, and the use of fast time simulation on a digital computer to study the operation of a complete terminal area traffic control system, are briefly demonstrated. Mathematical models are used to analyze the capacity of race track holding patterns, the laddering operation, and the instrument landing system (ILS) funnel with time separations at the gate. The results of a fast time simulation on an IBM 7094, for an advanced method of providing sequencing and spacing for a single ILS runway are given. The landing system demonstrates a capacity of 32 landings/hr, along with runway availability for 20 takeoffs.
Learning to verify branching time properties

We present a new model checking algorithm for verifying computation tree logic (CTL) properties. Our technique is based on using language inference to learn the fixpoints necessary for checking a CTL formula instead of computing them iteratively as is done in traditional model checking. This allows us to analyze infinite or large state-space systems where the traditional iterations may not converge or may take too long to converge. We allow fairness constraints to be specified for verification of various liveness properties. The main challenge in developing a learning based model checking algorithm for CTL is that CTL properties express nested fixpoints. We overcome this challenge by developing a new characterization of CTL properties in terms of functions that have unique fixpoints. We instantiate our technique to systems in which states are encoded as strings and use a regular inference algorithm to learn the CTL fixpoints. We prove that if the fixpoints have a regular representation, our procedure will always terminate with the correct answer. We have extended our Lever tool to use the technique presented in this paper and demonstrate its effectiveness by verifying a number of parametric and integer systems.
X-ray characterization of picosecond laser plasmas☆

Abstract Short-lived plasmas, produced by focussing a 0.58 μm, 1 ps, 1 mJ dye laser beam to 10 13 –10 14 W cm -2 onto solid planar targets, are diagnosed by a photoconductive detector, pinhole camera, X-ray stream camera and by shadowgraphy. 1–5% conversion efficiency to a Z (> 40) targets at 1–2 × 10 14 W cm -2 . Electron temperatures of 200 eV and higher are deduced from spatially resolved absolute X-ray yields. The heated material depth for carbon is measured to be 200 A, corresponding to a low intensity optical depth of one. The quasi point-like nature of > 1 keV X-rays from these plasmas is used to image a 20 μm diameter wire with 3000 A resolution in one dimension.
Separation of hydrogen isotopes via single column pressure swing adsorption

An experimental study of the separation of gaseous isotopic species of hydrogen was conducted using a single column pressure swing adsorption process. Vanadium monohydride served as the solid phase and the feed was hydrogen containing a trace of HT. The separations observed were shown to be controlled by a kinetic isotope effect. Comparisons were made with other cyclic separation processes employing vanadium hydride.
Dressed Coherent States of the Anharmonic Oscillator

Driving a damped, anharmonic oscillator produces stable, steady-state excitations according to the familiar classical description. A quantum mechanical description, however, shows the surprising result that such excitations are intrinsically unstable, and can be much smaller than classical expectations. We illustrate by calculating the motion of one electron in a magnetic field. This physically realizable system is among the simplest of nonlinear systems, being anharmonic because of special relativity and being damped by the spontaneous emission of synchrotron radiation. {copyright} {ital 1997} {ital The American Physical Society}
Turbulent exchange of momentum, mass, and heat between fluid streams and pipe wall

Abstract A new correlation is presented to describe mass and heat transfer to a fluid in a fully developed turbulent flow in a pipe. The correlation differs from earlier empirical relations in that it is based on a theoretical continuous eddy-viscosity distribution from the wall to the center of the pipe. Transfer rates calculated from the new correlation are in excellent agreement with experimental data on mass and heat transfer to fluid streams.
Electrical Power Supply and Controls for a Remotely Operated Glass Melter for Nuclear Waste

An electrical power supply and the controls and instruments used for a joule-heated glass melter for nuclear waste are discussed. Remotely replaceable interconnection wiring assemblies for the power, controls, and instruments are also described.
A program for calculating and plotting soft-X-ray optical interaction coefficients for molecules

Abstract Comprehensive tables for atomic scattering factor components f 1 and f 2 were compiled by Henke et al. for the extended photon region of 350–10000 eV. Accurate calculations of optical interaction coefficients for absorption, reflection and scattering by material systems (e.g. filters, multi-layers, etc.), which have widespread application, can be based simply upon the atomic scattering factors for the elements comprising the material, except near the absorption threshold energies. These calculations based upon the weighted sum of f 1 and f 2 for each atomic species present can be very tedious if done by hand. This led us to develop Optical Constants Grapher (OCG), a user-friendly program to perform these calculations on an IBM PC or compatible computer. By entering the chemical formula, density and thickness of up to six molecules, values of f 1 , f 2 , mass absorption, transmission efficiencies, attenuation lengths, mirror reflectivities and complex indices of refraction can be calculated and plotted as a function of energy or wavelength. This program and its user's manual are available from the authors.
Too Busy To Serve? An Examination of the Influence of Overboarded Directors

Overboarded directors (i.e., those serving on too many boards) have come under recent attack. The accusation is that such directors are ‘stretched’ by several directorships and therefore cannot fulfil their governance responsibility. This study investigates the impact of overboarded directors upon key strategic decisions such as corporate acquisitions. Based on our examination of acquisition outcomes, we found that such directors are important sources of knowledge and enhance acquisition performance. Moreover, they represent an important complement to inside and non-overboarded outside directors.
Numerical investigation of turbulent channel flow

Fully developed turbulent channel flow was simulated numerically at Reynolds number 13800, based on centerline velocity and channel halt width. The large-scale flow field was obtained by directly integrating the filtered, three dimensional, time dependent, Navier-Stokes equations. The small-scale field motions were simulated through an eddy viscosity model. The calculations were carried out on the ILLIAC IV computer with up to 516,096 grid points. The computed flow field was used to study the statistical properties of the flow as well as its time dependent features. The agreement of the computed mean velocity profile, turbulence statistics, and detailed flow structures with experimental data is good. The resolvable portion of the statistical correlations appearing in the Reynolds stress equations are calculated. Particular attention is given to the examination of the flow structure in the vicinity of the wall.
KOYAANISMUUYAW: THE HYPOTHESIS OF A PERENNIALLY DICHOTOMOUS TRITON

The Voyager 2 observation that, at the height of a “major” southern summer, the southern “cap” of Triton extends nearly to the equator, and the northern temperate regions (where they can be seen) are relatively dark even though nitrogen frost should be accumulating at those latitudes, has prompted us to propose a hypothesis that there has been a net non-reversable flux of surficial volatiles on Triton from the northern hemisphere to the southern hemisphere over much of the satellite's history and up to the present. The north-south hemispherical albedo difference is permanent and overwhelms the seasonal effect on volatile transport. This hypothesis assumes that volatile erosion, transport, and deposition has been in the form of sublimation, advection, and precipitation.
The inflation sector of extended inflation

In extended inflation the inflationary era is brought to a close by the process of percolation of true vacuum bubbles produced in a first-order phase transition. In this paper I discuss several effects that might obtain if the Universe undergoes an inflationary first-order phase transition.
Flavor parity breaking in the NJL model with Wilson fermions

The Nambu—Jona-Lasinio model is chirally symmetric. Addition of a Wilson term explicitly breaks this symmetry and leaves the model with a remaining parity-flavor symmetry. In the approximation of a large number of colors it has been shown that there is a phase where the remaining parity-flavor symmetry is spontaneously broken and that on the phase boundary all pions become massless. Using numerical simulations we confirm the existence of this phase for the case of two flavors and two colors. We also confirm the large N prediction of the existence of large finite size effects that alter the shape of the phase boundary dramatically when periodic boundary conditions are used.
GLOBAL RANDOM-FIELD SPIN-GLASS PHASE DIAGRAMS IN TWO AND THREE DIMENSIONS

An Ising model including field randomness and $\ifmmode\pm\else\textpm\fi{}J$ bond randomness is studied by renormalization-group theory in spatial dimensions $d=2$ and 3. In $d=3,$ with field randomness but no $\ifmmode\pm\else\textpm\fi{}J$ randomness, ferromagnetic and paramagnetic phases occur with no intervening spin-glass phase. Also in $d=3,$ at sufficient $\ifmmode\pm\else\textpm\fi{}J$ randomness, a spin-glass phase occurs, but is replaced by the paramagnetic phase for any nonzero random field, also implying its disappearance for any nonzero uniform field. In $d=2,$ no ferromagnetic phase under random fields and no spin-glass phase occur. Global phase diagrams uniting the random-field and spin-glass problems are evaluated. The strong violation of critical phenomena universality, previously found adjoining random-bond tricriticality in $d=3,$ is seen here in $d=2.$
Random Walks That Find Perfect Objects and the Lovász Local Lemma

We give an algorithmic local lemma by establishing a sufficient condition for the uniform random walk on a directed graph to reach a sink quickly. Our work is inspired by Moser’s entropic method proof of the Lovasz Local Lemma (LLL) for satisfiability and completely bypasses the Probabilistic Method formulation of the LLL. In particular, our method works when the underlying state space is entirely unstructured. Similarly to Moser’s argument, the key point is that the inevitability of reaching a sink is established by bounding the entropy of the walk as a function of time.
An unconstrained optimization approach for finding real eigenvalues of even order symmetric tensors

Let $n$ be a positive integer and $m$ be a positive even integer. Let ${\mathcal A}$ be an $m^{th}$ order $n$-dimensional real weakly symmetric tensor and ${\mathcal B}$ be a real weakly symmetric positive definite tensor of the same size. $\lambda \in \mathbb{R}$ is called a ${\mathcal B}_r$-eigenvalue of ${\mathcal A}$ if ${\mathcal A} x^{m-1} = \lambda {\mathcal B} x^{m-1}$ for some $x \in \mathbb{R}^n \backslash \{0\}$. In this paper, we introduce two unconstrained optimization problems and obtain some variational characterizations for the minimum and maximum ${\mathcal B}_r$--eigenvalues of ${\mathcal A}$. Our results extend Auchmuty's unconstrained variational principles for eigenvalues of real symmetric matrices. This unconstrained optimization approach can be used to find a Z-, H-, or D-eigenvalue of an even order weakly symmetric tensor. We provide some numerical results to illustrate the effectiveness of this approach for finding a Z-eigenvalue and for determining the positive semidefiniteness of an even order symmetric tensor.
AN OVERVIEW OF QUANTUM COSMOLOGY

Hawking’s theory of quantum cosmology is the most important stage in understanding our universe since the big bang model. In principle, one can predict everything in the universe solely from physical laws. All main results within this framework have been reviewed in this paper.
DIRECTIONAL IN-PLANE PERMEABILITIES OF GEOTEXTILES

Abstract Typical studies of in-plane flow of fluids through geotextiles yield an average value for the fabric permeability and transmissivity. We introduce a new method which quantifies directional in-plane intrinsic permeabilities. The flow front which develops when fluid is introduced into a geotextile sample and allowed to flow only in the plane of the material highlights primary flow directions due to fabric anisotropies, and also reveals nonuniformities and inhomogeneities in the fabric. Temporal radial expansion measurements allow one to obtain values for directional geotextile intrinsic permeabilities.
The Aerocapacitor: An Electrochemical Double‐Layer Energy‐Storage Device

The authors have applied unique types of carbon foams developed at Lawrence Livermore National Laboratory (LLNL) to make an {open_quotes}aerocapacitor{close_quotes}. The aerocapacitor is a high power-density, high energy-density, electrochemical double-layer capacitor which uses carbon aerogels as electrodes. These electrodes possess very high surface area per unit volume and are electrically continuous in both the carbon and electrolyte phase on a 10 nm scale. Aerogel surface areas range from 100 to 700 m{sup 2}/cc (as measured by BET analysis), with bulk densities of 0.3 to 1.0 g/cc. This morphology permits stored energy to be released rapidly, resulting in high power densities (7.5 kW/kg). Materials parameterization has been performed, and device capacitances of several tens of Farads per gram and per cm{sup 3} of aerogel have been achieved.
Carcinoma of the Urethra in Women

Abstract Purpose: This analysis was performed to evaluate the influence of clinical and treatment factors on local tumor control, survival, and complications for women with urethral carcinoma. Methods and Materials: The records of 44 women with carcinoma of the urethra were reviewed. Their age ranged from 37 to 89 years (mean, 67 years). Mean follow-up time was 8.25 years. The stages of disease were T1 in eight, T2 in five, T3 in 22, and T4 in nine. Treatment was with surgery in 7, radiotherapy in 25, and combined surgery and radiotherapy in 12. Results: The 5-year overall survival was 42% and the 5-year cause-specific survival was 40%. At the time of last follow-up, 11 women were alive and 33 were dead. Recurrence of tumor occurred in 27 women and was the cause of death for 23. Recurrence was local in 8, local and distant in 15, and distant in 4. Severe complications occurred in nine women (20%). The severe complication rate was 29% (2 of 7) for women treated with surgery, 24% (6 of 25) for women treated with radiotherapy, and 8% (1 of 12) for women treated with surgery and radiotherapy. A multivariate analysis was performed to evaluate the interaction of tumor size, histology, and location, and lymph node status. This analysis indicated that tumor size and histology were independent prognostic factors for survival and local tumor control. Adenocarcinoma occurred in 13 women, and none of them were alive at 5 years. Only 1 of 10 women with tumors greater than 4 cm was alive at 5 years. Conclusions: The most significant clinical factors affecting prognosis were tumor size and histology. Tumor location was not an independent prognostic variable. None of the women with adenocarcinoma, and only one woman with a tumor greater than 4 cm was alive at 5 years, irrespective of modality of treatment. Aggressive treatment resulted in a high complication rate.
Complementarity Paradox Solved: Surprising Consequences

Afshar et al. claim that their experiment shows a violation of the complementarity inequality. In this work, we study their claim using a modified Mach-Zehnder setup that represents a simpler version of the Afshar experiment. We find that our results are consistent with Afshar et al. experimental findings. However, we show that within standard quantum mechanics the results of the Afshar experiment do not lead to a violation of the complementarity inequality. We show that their claim originates from a particular technique they use to analyze their results. In their analysis, they assume a classical concept, that particles have a definite trajectory before detection, thus, they obtain which-way information by particle detection plus path extrapolation by applying momentum conservation. This analysis technique is standard in experimental particle physics. Important discoveries such as the detection of vector bosons have been made through the application of this technique. We note that particle detection plus path extrapolation is a suitable technique within de Broglie-Bohm theory of quantum mechanics.
Radiative transfer in spectrally dissimilar absorbing-emitting-scattering adjacent mediums

Structure of radiation field in a cylindrical medium having two regions of different, but uniform absorption and scattering coefficients is analyzed. Fundamental aspects of the problem are elucidated by considering the case of a gray medium. It is shown for example that for unequal absorption coefficients in the two regions, both emission and absorption rates are discontinuous at the interface of the two regions, but the heat flux and incident radiation are continuous. As an application of the analysis, the influence on heat transfer of spatial distribution of particles in a coal-burning swirl combustor is investigated. In the example application, spectral calculations are performed spanning over the broad frequency range of the thermal radiation spectrum.
Quantum supergroups IV: the modified form

We construct a canonical basis for a class of tensor product modules of a quantum covering group associated to a Kac–Moody Lie superalgebra of anisotropic type, and use these bases to construct a canonical basis for the modified form of a quantum covering group.
A Single Gene Causes an Interspecific Difference in Pigmentation in Drosophila

The genetic basis of species differences remains understudied. Studies in insects have contributed significantly to our understanding of morphological evolution. Pigmentation traits in particular have received a great deal of attention and several genes in the insect pigmentation pathway have been implicated in inter- and intraspecific differences. Nonetheless, much remains unknown about many of the genes in this pathway and their potential role in understudied taxa. Here we genetically analyze the puparium color difference between members of the virilis group of Drosophila. The puparium of Drosophila virilis is black, while those of D. americana, D. novamexicana, and D. lummei are brown. We used a series of backcross hybrid populations between D. americana and D. virilis to map the genomic interval responsible for the difference between this species pair. First, we show that the pupal case color difference is caused by a single Mendelizing factor, which we ultimately map to an ∼11-kb region on chromosome 5. The mapped interval includes only the first exon and regulatory region(s) of the dopamine N-acetyltransferase gene (Dat). This gene encodes an enzyme that is known to play a part in the insect pigmentation pathway. Second, we show that this gene is highly expressed at the onset of pupation in light brown taxa (D. americana and D. novamexicana) relative to D. virilis, but not in the dark brown D. lummei. Finally, we examine the role of Dat in adult pigmentation between D. americana (heavily melanized) and D. novamexicana (lightly melanized) and find no discernible effect of this gene in adults. Our results demonstrate that a single gene is entirely or almost entirely responsible for a morphological difference between species.
Accessory-mineral fractionation of rare-earth element (REE) abundances in granitoid rocks

Abstract Accessory minerals with large distribution coefficients ( K d 's) for the REE have the potential to strongly affect the evolution of REE abundances during igneous differentiation (e.g., crystallization, melting, assimilation). A cogenetic suite of lavas (basaltic andesites through high-silica rhyolites) from the Batopilas area of Mexico, which preserve petrographic evidence for apatite and zircon saturation, is used to illustrate and confirm an inverse geochemical approach to recognizing early-liquidus accessory-mineral saturation. The transition in behavior of Zr from an incompatible trace element in basaltic andesites and dacites, to an essential structural constituent (ESC) in high-silica rhyolites, marks the onset of zircon crystallization. A previously published zircon saturation model provides liquidus temperatures that support the interpretation that three high-silica rhyolites represent zircon-saturated melts while one has excess zircon. These results contradict the previous study in which zircon fractionation had been argued against. The potential effect of zircon fractionation and accumulation on REE abundances in the samples is evaluated and contributes to an improved petrogenetic interpretation. A cogenetic suite of granitoid samples from the Saganaga tonalite, Minnesota-Ontario, North America, is characterized by apparently strongly compatible behavior of the REE. Apatite, zircon and sphene are the observed high-REE- K d accessory minerals. Forward and inverse modelling approaches provide no evidence that accessory-mineral fractionation contributed to the behavior of the REE during differentiation of the samples. The data instead suggest that the REE characteristics of the samples were already established by other petrogenetic processes, prior to the samples becoming saturated with the observed accessory minerals.
Reliability of causality assessment for drug, herbal and dietary supplement hepatotoxicity in the Drug-Induced Liver Injury Network (DILIN).

Background & Aims Because of the lack of objective tests to diagnose drug-induced liver injury (DILI), causality assessment is a matter of debate. Expert opinion is often used in research and industry, but its test–retest reliability is unknown. To determine the test–retest reliability of the expert opinion process used by the Drug-Induced Liver Injury Network (DILIN). Methods Three DILIN hepatologists adjudicate suspected hepatotoxicity cases to one of five categories representing levels of likelihood of DILI. Adjudication is based on retrospective assessment of gathered case data that include prospective follow-up information. One hundred randomly selected DILIN cases were re-assessed using the same processes for initial assessment but by three different reviewers in 92% of cases. Results The median time between assessments was 938 days (range 140–2352). Thirty-one cases involved >1 agent. Weighted kappa statistics for overall case and individual agent category agreement were 0.60 (95% CI: 0.50–0.71) and 0.60 (0.52–0.68) respectively. Overall case adjudications were within one category of each other 93% of the time, while 5% differed by two categories and 2% differed by three categories. Fourteen per cent crossed the 50% threshold of likelihood owing to competing diagnoses or atypical timing between drug exposure and injury. Conclusions The DILIN expert opinion causality assessment method has moderate interobserver reliability but very good agreement within one category. A small but important proportion of cases could not be reliably diagnosed as ≥50% likely to be DILI.
Directions in civil aviation 1980-2000

The following future directions in civil aviation are considered: (1) greater economy and efficiency in passenger and cargo air service at subsonic speeds, and improved utility and safety for general aviation, (2) greatly improved short haul air transportation using turbofan or turboprop aircraft, and subsequently, rotorcraft and V/STOL aircraft, and (3) supersonic, and ultimately hypersonic, air transportation for transoceanic long range flight. Attention is also given to new directions in research and technology.
Cash-Flow Tax

The cash-flow tax has been proposed as an alternative to the corporate income tax on grounds that it would define the tax base more clearly and more simply in the face of widespread departures from the comprehensive income tax of actual practice. The cash-flow tax, and its variants, would require careful design. Simplicity may prove elusive because of anticipated administrative problems related to tax avoidance and evasion through transfer pricing, to inflation adjustments, and to incompatibility with existing international tax regimes. Thus, the tax remains theoretically attractive but difficult to implement.
Direct Reduction of Aero-Optical Aberrations by Large Structure Suppression Control in Turbulence

Direct reduction of aero-optical aberrations incurred by a laser propagated through a refractive turbulent flow has been achieved by introducing plasma into the flow at various pulsing frequencies. The plasma is generated by a dielectric barrier discharge device which operates at elevated pressure to force flow near the separation point of a single-stream shear layer that is generated in a variable pressure wind-tunnel testing facility with Re ∼ 6 x 10 6 and M ∞ ∼ 0.9. The levels of aero-optical aberrations present in the laser are determined by directly profiling the propagated laser using a high-resolution Shack-Hartmann wave frontsensor with ∼ 1000 microlenses. Reductions in the ensemble-averaged optical path difference root mean square of up to 27% were achieved. Whole-field shadowgraphs were recorded for various forcing frequencies and indicate that the observed aero-optical effects are the result of modifications in the level of organization of the large structures. Because the dominant contributions to the aberrations in unforced flows are caused by large-scale organized structures, our findings indicate that the mechanism by which the significant reduction is observed in the forced experiments is due to large-scale suppression of the turbulent structures directly effected by the pulsed plasma actuator. Conversely, increases in the aero-optical aberrations, which have also been observed at certain plasma pulsing frequencies, are the result of large-scale regularization of the structures within the turbulent shear layer. The presence of these large-scale suppression and regularization mechanisms is confirmed by the shadowgraphs at forced cases compared with the unforced case.
Synthesis of 4-(2-acetoxyethoxymethyl)-6-methyl-1,2,4-triazin-3(4H)-one 1-oxide as thymidine analogue

Alkylation of the sodium salt and the trimethyl silylated derivatives of 6-methyl-1,2,4-triazin-3(4H)-one 1-oxide with chloromethoxyethyl acetate, n-hexyl chloride and benzyl bromide gave the 4-substituted products. However, attempts to achieve the ring closure of N4-(2-acetoxyethoxymethyl)thiosemicarbazide with bicarbonyl compounds to the corresponding as-triazines under different reaction conditions was not possible without disruption of the acetoxyethoxymethyl moiety. Although the as-triazine nucleoside analog II did not show antileukemic activity, this and other 4-alkylated as-triazine 1-oxides revealed good growth inhibitory effects against a representative spectrum of microorganisms.
University participation in strategic business planning

Publisher Summary Strategic planning is not something that every firm does. Few corporations do it—and even fewer do it well. Few colleges and universities even attempt it. The scope of the task is immense. Strategic planners are expected to accomplish more than wizards in the courts of ancient kings. They are expected to pull clear concepts of trends, opportunities, and limits from messy data about messy environments. They are asked to frame statements of mission and suggestions for goals that would affect decisions long beyond the time horizon for which they can make confident predictions. They are agents for change, but—at the same time—prisoners of what a company is and has been. Although a planning effort draws on experts of many kinds, the heart of the effort involves coming to terms with people in the firm who have responsibility for action. A planning document means little unless it relates to the lives and work of the people who must carry it out. Planning presumes some power to predict and to make sense out of the disorder in complex environments.
Qualitative and quantitative comparison of government and industry agility metrics

Government and industry have proposed various agility metrics in an effort to define and measure aircraft agility. Each of the agility metrics proposed measure different quantities related to aircraft performance and each, if designed to, would increase aircraft performance. The intent of this paper is not to choose the "best" or "most correct" agility metric but to compare their similarities and differences qualitatively and quantitatively compare their sensitivity to variations in agility-related design parameters.
Growing through Cycles in an Infinitely Lived Agent Economy

Abstract This paper extends the analysis of K. Matsuyama (Econometrica67 (1999), 335–347) to the case of an infinitely lived representative agent economy. The economy grows endogenously through endogenous fluctuations, perpetually moving back and forth between two phases. In one phase, there is no innovation, the market structure is competitive, and the economy grows solely by capital accumulation. In the other phase, new goods are introduced and the market structure is monopolistic. In the long run, both investment and innovation grow at the same rate, but the economy alternates between the periods of high investment and the periods of higher innovation. Journal of Economic Literature Classification Numbers: E32, O11.
Global search for planar and three-dimensional periodic orbits near Europa

A global grid search is performed to find axi- and doubly-symmetric periodic orbits in the restricted three-body problem using the dimensioned parameters associated with the Jupiter-Europa system. Local differential correctors are applied to regions of the initial condition phase space that appear to be near solutions. A three-dimensional initial condition mesh with billions of nodes is evaluated, and over 600,000 periodic solutions are identified. Families of direct and retrograde solutions, both new and previously published, are identified and discussed. Stability is analyzed for each solution and general regions of stability are noted. Of the most promising results is the observation and characterization of a large class of stable yet highly-inclined direct orbits. Finally, all of the solutions and associated properties are archived. The resulting database is a practical reference for preliminary design of missions to Europa.
Grounded in the World: Developmental Origins of the Embodied Mind

Piaget's (1952) question of how the adult mind emerges from the sensorimotor infant is still the framing issue for developmental psychology. Here I suggest that real-life skill is better understood if the sensorimotor origins of cognition are not abandoned. Skilled people are not only better at both abstract and logical thinking but also at processing the world "online" and, most important, seamlessly and rapidly shifting between the two modes. I illustrate the tight coupling between action, perception, and cognition in early life and propose that this coupling remains but becomes more flexibly adaptive. Further, I show that the language of dynamics is appropriate to capture these mind-body-world interconnections.
Economic uncertainty and corruption: evidence from a large cross-country data set

A vast amount of research has considered numerous causes and correlates of corruption. Also, there have been many studies of the consequences of various forms of uncertainty. However, exploration of the nexus between economic uncertainty and corruption appears scarce. After providing an intuitive and heuristic linkage between general economic uncertainty and corruption, this article uses a large cross-country data set to augment a fairly standard model with simple proxies for uncertainty and to investigate how economic uncertainty might affect the prevalence of corruption. In addition, a quantile-regression framework is used to judge how the strength of various covariates may differ with the level of corruption. Seven main points emerge from the estimates. First, economic uncertainty is associated positively with corruption, and the relation seems to be robust across measures of uncertainty and corruption. Second, quantile-regression estimates indicate considerable parametric heterogeneity across the dist...
Fatigue resistance of welded details enhanced by ultrasonic impact treatment (UIT)

Abstract Enhancement of the fatigue resistance of welded transverse stiffeners and cover plate details by ultrasonic impact treatment (UIT) was evaluated in 18 full-scale W27×129 rolled beam specimens. Fatigue tests were conducted under constant amplitude loading at various stress range levels and at two minimum stress levels simulating the effect of sustained load. The test specimens were investigated for fatigue crack initiation and propagation. Distributions of residual stresses adjacent to the weld toe were determined before and after the treatment. Test results indicated that UIT enhanced the fatigue performance of all treated details by improving the weld toe profile, changing microstructure and introducing beneficial compressive residual stresses at the treated weld toe. The treatment effectively elevated the fatigue crack growth threshold and the fatigue limit without changing the slope of the S–N curve.
A Quantum Mechanical Approach for the Simulation of Si/SiO2 Interface Roughness Scattering in Silicon Nanowire Transistors

In this work, we present a quantum mechanical approach for the simulation of Si/SiO2 interface roughness scattering in silicon nanowire transistors (SNWTs). The simulation domain is discretized with a three-dimensional (3D) finite element mesh, and the microscopic structure of the Si/SiO2 interface roughness is directly implemented. The 3D Schrodinger equation with open boundary conditions is solved by the non-equilibrium Green’s function method together with the coupled mode space approach. The 3D electrostatics in the device is rigorously treated by solving a 3D Poisson equation with the finite element method. Although we mainly focus on computational techniques in this paper, the physics of SRS in SNWTs and its impact on the device characteristics are also briefly discussed.
A new approach to valuing a life

Abstract Because the issue of how to put a monetary value on a life will always be controversial, this paper presents an alternative approach that can in certain circumstances avoid the use of monetary values. The alternative approach uses time as the numeraire. This numeraire can handle both the ex ante and ex post approaches to valuing a life. After showing how a simple two-period consumer choice problem can be translated into terms of time, the paper considers an application that involves reformulating the data used to evaluate the 55 mph speed limit decision in the United States.