cssi/SciSciGPT-SciSciNet huggingface dataset:
Band-Sifting Decomposition for Image-Based Material Editing

Photographers often “prep” their subjects to achieve various effects; for example, toning down overly shiny skin, covering blotches, etc. Making such adjustments digitally after a shoot is possible, but difficult without good tools and good skills. Making such adjustments to video footage is harder still. We describe and study a set of 2D image operations, based on multiscale image analysis, that are easy and straightforward and that can consistently modify perceived material properties. These operators first build a subband decomposition of the image and then selectively modify the coefficients within the subbands. We call this selection process band sifting.We show that different siftings of the coefficients can be used to modify the appearance of properties such as gloss, smoothness, pigmentation, or weathering. The band-sifting operators have particularly striking effects when applied to faces; they can provide “knobs” to make a face look wetter or drier, younger or older, and with heavy or light variation in pigmentation. Through user studies, we identify a set of operators that yield consistent subjective effects for a variety of materials and scenes. We demonstrate that these operators are also useful for processing video sequences.
ON HEAVY ELEMENT ENRICHMENT IN CLASSICAL NOVAE

Many classical nova ejecta are enriched in CNO and Ne. Rosner and coworkers recently suggested that the enrichment might originate in the resonant interaction between large-scale shear flows in the accreted H/He envelope and gravity waves at the interface between the envelope and the underlying C/O white dwarf (WD). The shear flow amplifies the waves, which eventually form cusps and break. This wave breaking injects a spray of C/O into the superincumbent H/He. Using two-dimensional simulations, we formulate a quantitative expression for the amount of C/O per unit area that can be entrained, at saturation, into the H/He. The fraction of the envelope that is enriched depends on the horizontal distribution of shear velocity and the density contrast between the C/O WD and the H/He layer but is roughly independent of the vertical shape of the shear profile. Using this parameterization for the mixed mass, we then perform several one-dimensional Lagrangian calculations of an accreting WD envelope and consider two scenarios: that the wave breaking and mixing is driven by the convective flows and that the mixing occurs prior to the onset of convection. In the absence of enrichment prior to ignition, the base of the convective zone, as calculated from mixing-length theory with the Ledoux instability criterion, does not reach the C/O interface. As a result, there is no additional mixing, and the runaway is slow. In contrast, the formation of a mixed layer during the accretion of H/He, prior to ignition, causes a more violent runaway. The envelope can be enriched by 25% of C/O by mass (consistent with that observed in some ejecta) for shear velocities, over the surface, with Mach numbers 0.4.
Synthesis of 1,2-diheteroatom-substituted alkenes via rhodium-catalyzed intramolecular hydrogen transfer.

While 1,2-diheteroatom-substituted alkenes represent useful synthetic building blocks, there are no simple, general procedures available for preparation of such compounds. We describe here a simple catalytic procedure based on rhodium C−H bond activation for the synthesis of diheteroatom alkenes of the type R3SiOCHCHG (G = −OR, −NRR‘).
A CFD model for biomass fast pyrolysis in fluidized-bed reactors

Abstract In this work, an Euler–Euler multiphase CFD model is proposed for continuous fast pyrolysis of biomass in a fluidized-bed reactor. In the model, a lumped, multi-component, multi-stage kinetic model is applied to describe the pyrolysis of a biomass particle. Variable particle porosity is used to account for the evolution of the particle's physical properties. Biomass is modeled as a composite of three reference components: cellulose, hemicellulose, and lignin. Pyrolysis products are categorized into three groups: gas, tar vapor (bio-oil), and solid char. The particle kinetic processes and their interactions with the reactive gas phase are modeled with a multi-fluid description derived from the kinetic theory of granular flows. A time-splitting approach is applied to decouple the convection and reaction calculations using a synchronized time step. The CFD model is employed to study the fast pyrolysis of both cellulose and bagasse in a lab-scale fluidized-bed reactor. The dynamics, particle heating, reaction of the biomass phase, char formation, elutriation, and spatial distribution of tar and gas inside the reactor are investigated. The yields of tar, gas, and char are also discussed.
Synthesis of a tetracyclic substructure of manzamine A

Abstract A synthesis of tetracyclic manzamine A substructure 28 is described. The route involves (1) a new approach to perhydroisoquinolines, (2) a Mitsunobu reaction that process with net retention of configuration using a new N-acyl sulfonamide ( 16 ) and (3) a high yield preparation of a Δ 3,4 -azocine via an intramolecular N-alkylation.
Experimental results in heavy flavor physics

The interplay of experiment and theory is explored in the context of current data on b and c decay. Measurements of |V cb | and |V ub | are extracted from existing data. Conservative estimates give $\left|V_{cb}\right|=(42.4\pm 1.2_{exp} \pm 2.3_{thy})\times 10^{-3}$ and |V ub |=(3.90± 0.16 exp ± 0.53 thy ) × 10–3. Using these values along with data on B d , B s mixing and CP violation in the K L system, the allowed region of the CKM parameters ρ and η is derived. Tests of factorization in two-body hadronic B decays to one heavy and one light meson are shown and compared with modern theories which are also used to see if there is new physics in two-body B decays to light mesons. The two new narrow D sJ states, discovered by BaBar and CLEO, respectively, are interpreted in light of the observation of these states in B decays by Belle. PACS: 13.25.Hw Decays of bottom mesons – 13.20.Fc Decays of charmed mesons
Heteroannulation of chromium carbene complexes. A novel and efficient pyrrole synthesis

The heteroannulations of imino complexes are remarkably efficient and general. They are very highly chemoselective, giving only pyrrole products, and also highly regioselective, giving only a single pyrrole with terminal acetylenes
A Comparison of Statistical and Dynamical Downscaling of Winter Precipitation over Complex Terrain

AbstractStatistical downscaling is widely used to improve spatial and/or temporal distributions of meteorological variables from regional and global climate models. This downscaling is important because climate models are spatially coarse (50–200 km) and often misrepresent extremes in important meteorological variables, such as temperature and precipitation. However, these downscaling methods rely on current estimates of the spatial distributions of these variables and largely assume that the small-scale spatial distribution will not change significantly in a modified climate. In this study the authors compare data typically used to derive spatial distributions of precipitation [Parameter-Elevation Regressions on Independent Slopes Model (PRISM)] to a high-resolution (2 km) weather model [Weather Research and Forecasting model (WRF)] under the current climate in the mountains of Colorado. It is shown that there are regions of significant difference in November–May precipitation totals (>300 mm) between th...
Boiling performance of single-layered enhanced structures

A study of pool boiling at atmospheric pressure from single-layered enhanced structures was conducted for a dielectric fluorocarbon liquid (PF 5060). The parameters investigated in this study were: (a) Heat flux (1-45 W/cm 2 ); (b) width of the microchannels (65-105 μm); and (c) microchannel pitch (0.2-0.7 mm). The boiling performance of the enhanced structures was found to increase with the increase in channel width and decrease in channel pitch. A simple single line curve fit is provided as a practical way of predicting the data over the entire nucleate boiling regime. The exponent n in the single line power curve fit was found to be between I and 2. The modes of boiling from an enhanced structure proposed by previous researchers were unable to explain the boiling curves obtained in this study. The present data are explained in light of the contribution from the top finned surface of the enhanced structure.
Formation of hub cities : transportation cost advantage and population agglomeration

Abstract Many cities are located on rivers or coasts. Such cities developed as transportation hubs or markets for interregional trade, since these locations provide better access to other regions. Local products are collected at such hubs, and interregional trade then takes place among these transportation hubs. As the volume of trade between hubs increases, more workers are needed in order to meet labor demand for shipping and handling commodities, resulting in population agglomeration at such hubs. Formalizing the mechanism described above, this paper constructs a simple three location general equilibrium model, in which transportation hubs and population agglomeration emerge endogenously.
The 78.4 day period of cygnus XR-1

A search for a 78.4 day modulation in the high energy X-ray flux observed with OSO-8 and in the U-band optical polarization is reported. It is suggested that if such a modulation does exist, it is more likely to be related to the rotation of the free modes of oscillation of the primary than to the existence of a third body in the system.
In Vivo Praying and Catastrophizing Mediate the Race Differences in Experimental Pain Sensitivity

Abstract Black individuals have a lower tolerance for experimental pain than white individuals. Black and white individuals also differ in their use of pain coping strategies, which may explain the race differences in pain sensitivity. We examined the extent to which situation-specific pain coping mediated black-white differences in pain sensitivity. We hypothesized that 1) black participants would demonstrate lower pain tolerance than white participants, 2) black participants would use different pain coping strategies than white participants, and 3) the differential use of these strategies would mediate the relationship between race and pain tolerance. Healthy college undergraduates (N = 190) participated in a cold pressor task and then completed the Coping Strategies Questionnaire–Revised to assess their situation-specific pain coping. Compared with white participants, black participants demonstrated lower pain tolerance, engaged in more situation-specific catastrophizing and praying, and ignored pain less frequently. Catastrophizing and praying were inversely related to pain tolerance and were significant mediators of the relationship between race and pain tolerance. The indirect effect of praying was stronger than that of catastrophizing. Race differences in pain sensitivity may be due, in part, to differences in the use of catastrophizing and praying as coping strategies. These results may help guide treatments addressing maladaptive pain coping. Perspective This study suggests that race differences in pain sensitivity may be due, in part, to the differential use of catastrophizing and praying strategies. Psychosocial treatments for pain should encourage patients to take an active role in their pain management.
ADAPTIVE OPTICS IMAGING OF A MASSIVE GALAXY ASSOCIATED WITH A METAL-RICH ABSORBER

The damped and sub-damped Lyα absorption (DLA and sub-DLA) line systems in quasar spectra are believed to be produced by intervening galaxies. However, the connection of quasar absorbers to galaxies is not well-understood, since attempts to image the absorbing galaxies have often failed. While most DLAs appear to be metal poor, a population of metal-rich absorbers, mostly sub-DLAs, has been discovered in recent studies. Here we report high-resolution K-band imaging with the Keck laser guide star adaptive optics (LGSAO) system of the field of quasar SDSSJ1323-0021 in search of the galaxy producing the z = 0.72 sub-DLA absorber. With a metallicity of 2-4 times the solar level, this absorber is one of the most metal-rich systems found to date. Our data show a large bright galaxy with an angular separation of only 125 from the quasar, well-resolved from the quasar at the high resolution of our data. The galaxy has a magnitude of K = 17.6-17.9, which corresponds to a luminosity of ≈3-6 L*. Morphologically, the galaxy is fitted with a model with an effective radius, enclosing half of the total light, of Re = 4 kpc and a bulge-to-total ratio of 0.4-1.0, indicating a substantial bulge stellar population. Based on the mass-metallicity relation of nearby galaxies, the absorber galaxy appears to have a stellar mass of 1011 M ☉. Given the small impact parameter (9.0 kpc at the absorber redshift), this massive galaxy appears to be responsible for the metal-rich sub-DLA. The absorber galaxy is consistent with the metallicity-luminosity relation observed for nearby galaxies, but is near the upper end of metallicity. Our study marks the first application of LGSAO for the study of the structure of galaxies producing distant quasar absorbers. Finally, this study offers the first example of a massive galaxy with a substantial bulge producing a metal-rich absorber.
Investigation of a Macromechanical Approach to Analyzing Triaxially-Braided Polymer Composites

A macro level finite element-based model has been developed to simulate the mechanical and impact response of triaxially-braided polymer matrix composites. In the analytical model, the triaxial braid architecture is simulated by using four parallel shell elements, each of which is modeled as a laminated composite. The commercial transient dynamic finite element code LS-DYNA is used to conduct the simulations, and a continuum damage mechanics model internal to LS-DYNA is used as the material constitutive model. The material stiffness and strength values required for the constitutive model are determined based on coupon level tests on the braided composite. Simulations of quasi-static coupon tests of a representative braided composite are conducted. Varying the strength values that are input to the material model is found to have a significant influence on the effective material response predicted by the finite element analysis, sometimes in ways that at first glance appear non-intuitive. A parametric study involving the input strength parameters provides guidance on how the analysis model can be improved.
Flows and solitary waves in unitary matrix models with logarithmic potentials

Abstract We investigate unitary one-matrix models coupled to bosonic quarks. We derive a flow equation for the square-root of the specific heat as a function of the renormalized quark mass. We show numerically that the flows have a finite number of solitary waves, and we postulate that their number equals the number of quark flavors. We also study the nonperturbative behavior of this theory and show that as the number of flavors diverges, the flow does not reach two-dimensional gravity.
Antitruncated Stellar Disks via Minor Mergers

We use hydrodynamic simulations of minor mergers of galaxies to investigate the nature of surface brightness excesses at large radii observed in some spiral galaxies: antitruncated stellar disks. We find that this process can produce the antitruncation via two competing effects: (1) merger-driven gas inflows that concentrate mass in the center of the primary galaxy and contract its inner density profile; and (2) angular momentum transferred outward by the interaction, causing the outer disk to expand. In our experiments, this requires both a significant supply of gas in the primary disk, and that the encounter be prograde with moderate orbital angular momentum. The stellar surface mass density profiles of our remnants both qualitatively and quantitatively resemble the broken exponentials observed in local face-on spirals that display antitruncations. Moreover, the observed trend toward more frequent antitruncation relative to classical truncation in earlier Hubble types is consistent with a merger-driven scenario.
Two plus blue equals green: Grapheme-color synesthesia allows cognitive access to numerical information via color

In grapheme-color synesthesia, graphemes (e.g., numbers or letters) evoke color experiences. It is generally reported that the opposite is not true: colors will not generate experiences of graphemes or their associated information. However, recent research has provided evidence that colors can implicitly elicit symbolic representations of associated graphemes. Here, we examine if these representations can be cognitively accessed. Using a mathematical verification task replacing graphemes with color patches, we find that synesthetes can verify such problems with colors as accurately as with graphemes. Doing so, however, takes time: ~250 ms per color. Moreover, we find minimal reaction time switch-costs for switching between computing with graphemes and colors. This demonstrates that given specific task demands, synesthetes can cognitively access numerical information elicited by physical colors, and they do so as accurately as with graphemes. We discuss these results in the context of possible cognitive strategies used to access the information.
Efficient optimal design of suspension systems for rotating shafts

A new technique is proposed for the optimum design of suspension systems for rotating shafts. In this approach the conventional method of trial and error search for optimum parameter values for a prescribed design configuration has been replaced by an efficient two-stage procedure. In the first stage a generic force is substituted for the suspension system to be designed and the absolute optimum (or limiting) performance characteristics of the shaft are computed. In the second stage, using a chosen suspension system configuration, parameter identification techniques are are applied to find the design parameters so that the suspension system will respond as close as possible to the absolute optimal performance. In this approach the repetitive shaft analyses required in the conventional search techniques are avoided. Hence, the new technique is relatively efficient computationally and is suitable for large systems. Both linear and nonlinear suspension systems can be designed. A simple Jeffcott rotor is used to demonstrate the new technique.
Hopes for the future of operations management

Abstract Operations Management has a much longer history than our sister functions in business: finance, marketing, accounting, etc. Yet, we still struggle with fewer majoring students, fewer and newer journals, less academic respect, greater student fear, and fewer professors. Yet, most of the physical and human assets in real-world organizations are still in the operations function and most of the excitement in industry lies in the operations area: TQM, JIT, supply chain management, ERP, mass customization, and so on. This paper will address some hopes for our future regarding practice, teaching, and research.
Automatic Screening of Normal and Abnormal Electrocardiograms by Means of a Digital Electronic Computer

SummaryThe spatial ventricular gradient was determined in 256 electrocardiograms by means of a digital electronic computer. This automatic procedure allowed separation of normal and abnormal records with a high degree of precision. Of all cases with old myocardial infarctions, which are of prime interest in electrocardiographic diagnosis, 98% were recognized as abnormal.
Constant and Equivariant Cyclic Cohomology

In this note, we prove that the constant and equivariant cyclic cohomology of algebras coincide. This shows that constant cyclic cohomology is rich and computable.
Prophylactic versus therapeutic castration in the total treatment of breast cancer.

For many years the rival merits of prophylactic vs therapeutic castration have been enthusiastically endorsed (mainly on empirical grounds) by those clinicians concerned with the total treatment of breast cancer.(‘*14 In premenopausal patients with operable breast cancer, is it wise to perform prophylactic castration as an adjunct to surgery or is it wiser to reserve this procedure for the palliative treatment of recurrent or metastatic disease? This is, indeed, the doctor’s dilemma! As long as the practice of medicine remained a “science of uncertainty and an art of probability” doctors were destined to be impaled upon the horns of this dilemma. However, today, fortunately, we are on the threshold of a new and exciting era in science-a new generation of radiometric testing called endocrine receptor assays. The results of these steroid hormone receptor assays can be a very specific and selective cytoplasmic binder for tumor tissue. When these results are combined with sophisticated nuclear scans and data gleaned from biochemical tumor markers this information may provide us with new and valuable guidelines for the resolution of this clinical dilemma, namely which patients will be most likely to respond favorably to castration, endocrine ablation or hormone therapy. Additional tests of hormone dependence currently under study may be even more valuable in the future.
Discrete implementation of the Groves–Ledyard mechanism

When implementing an economic institution in the field or in the laboratory, the participants’ action spaces and the institution’s outcomes are typically discrete, while our theoretical analysis of the institution often assumes the sets are continuous. Predictions by the continuous model generally turn out to be good approximations to the performance of the discrete implementation. We present an example in which the continuous version has a unique and Pareto efficient equilibrium, but in which the discrete version often has vastly more equilibria, many of them far from efficient. We show that the same phenomenon appears in two experiments investigating the Groves–Ledyard mechanism, and that it may account for the experimental results.
QED and the fundamental constants

Abstract A new set of values of the fundamental constants, based on a recent least-squares adjustment, has been recommended by CODATA. An overview of the experiments and theory that influence the values of the new set of constants will be given. Quantum electrodynamic (QED) theory plays a significant role in determining these constants and the consistency of the values obtained from various sources of information provides an important test of the theory.
A General Magneto-Elastic Model of Terfenol-D Particle Actuated Composite Materials

A new theory is presented of the nonlinear multi-axial magneto-elastic behavior of magnetostrictive particle actuated composite materials. The analysis assumes a uniform external magnetic field is operating on a large number of well-distributed, crystallographically and shape parallel ellipsoidal magnetostrictive particles encased in an elastic, nonmagnetic composite matrix. Comparisons between experimental and model magnetostriction results show that the model is able to provide a quantitatively correct dependence on particulate volume fraction and longitudinal stress and quantitatively accurate magnetostriction curves for both homogenous Terfenol-D rod and magnetically ordered Terfenol-D particulate actuated epoxy matrix composites over experimentally applied field ranges.
The Economics of Tenancy Rent Control

We consider a rent control regime where rent increases on, and eviction of, a sitting tenant are forbidden. When apartments become vacant landlords may negotiate new rents. If inflation exists, landlords prefer to rent to short-staying tenants. Since departure-date-contingent contracts are forbidden and landlords cannot tell whether tenants are short-stayers, an adverse selection problem arises, with a Pareto inefficient equilibrium. When tenant types are determined endogenously, multiple equilibria can arise where one equilibrium is Pareto dominated. Abolition of the rent control regime, cannot only shift the equilibrium out of this inferior outcome, but also result in across-the-board lowering of rents.
On the Spatial Statistics of Optical Flow

We present an analysis of the spatial and temporal statistics of "natural" optical flow fields and a novel flow algorithm that exploits their spatial statistics. Training flow fields are constructed using range images of natural scenes and 3D camera motions recovered from hand-held and car-mounted video sequences. A detailed analysis of optical flow statistics in natural scenes is presented and machine learning methods are developed to learn a Markov random field model of optical flow. The prior probability of a flow field is formulated as a Field-of-Experts model that captures the spatial statistics in overlapping patches and is trained using contrastive divergence. This new optical flow prior is compared with previous robust priors and is incorporated into a recent, accurate algorithm for dense optical flow computation. Experiments with natural and synthetic sequences illustrate how the learned optical flow prior quantitatively improves flow accuracy and how it captures the rich spatial structure found in natural scene motion.
Space transportation main engines for two-stage shuttles

Current studies are examining two-stage fully reusable vehicles, heavy-lift vehicles, and rocket engines for these vehicles. A previous study showed that several advanced engine designs could reduce the dry mass of a single-stage vehicle relative to designs with the baseline hydrocarbon and hydrogen engines. This paper reports the results of a similar study for two-stage vehicles. The results indicate that the advanced engines can reduce the dry mass of two-stage vehicles, and that the same engine can be used for both stages.
The concept of strong and weak virtual reality

We approach the virtual reality phenomenon by studying its relationship to set theory. This approach offers a characterization of virtual reality in set theoretic terms, and we investigate the case where this is done using the wellfoundedness property. Our hypothesis is that non-wellfounded sets (so-called hypersets) give rise to a different quality of virtual reality than do familiar wellfounded sets. To elaborate this hypothesis, we describe virtual reality through Sommerhoff's categories of first- and second-order self-awareness; introduced as necessary conditions for consciousness in terms of higher cognitive functions. We then propose a representation of first- and second-order self-awareness through sets, and assume that these sets, which we call events, originally form a collection of wellfounded sets. Strong virtual reality characterizes virtual reality environments which have the limited capacity to create only events associated with wellfounded sets. In contrast, the logically weaker and more general concept of weak virtual reality characterizes collections of virtual reality mediated events altogether forming an entirety larger than any collection of wellfounded sets. By giving reference to Aczel's hyperset theory we indicate that this definition is not empty because hypersets encompass wellfounded sets already. Moreover, we argue that weak virtual reality could be realized in human history through continued progress in computer technology. Finally, within a more general framework, we use Baltag's structural theory of sets (STS) to show that within this hyperset theory Sommerhoff's first- and second-order self-awareness as well as both concepts of virtual reality admit a consistent mathematical representation. To illustrate our ideas, several examples and heuristic arguments are discussed.
Single Pass Rub Phenomena—Analysis and Experiment

An experimental and analytical investigation is presented of contact phenomena for the case of a fully-dense copper gas path seal segment which is rubbed by a single steel blade tip at room temperature. The experiments were executed on a pendulum-type test device, with forces, rub energy, surface temperature and residual deformation being determined for each single-path rub test. The thermal and mechanical factors influencing single-pass rub surface temperatures were modeled analytically. It is found that large plastic strains occurred on or near the contact surface of the copper rub specimens. A study of the influence of various material properties on surface temperature showed that increased thermal conductivity of the stationary component played a role in lowering contact temperatures. Increased thermal conductivity of the moving blade tip component and increased thermal diffusivity of the stationary material also had a beneficial effect.
Foreign monopoly and optimal tariffs for the small open economy

Abstract In competitive markets a small open economy cannot improve its terms of trade by levying a tariff. With imperfectly competitive suppliers, such a country might be able to get better prices if its market is segmented from that in other countries. The paper points out that tariffs provide the kind of market segmentation required. The advisability of protection for a small country is shown to rest upon the asymmetry between its demand elasticity and the elasticity of demand on average in the market.
Catalytic Additions of Acylsilanes to Imines: An Acyl Anion Strategy for the Direct Synthesis of α-Amino Ketones

The addition of acylsilanes to imines catalyzed by neutral carbenes (or zwitterions) generated in situ from readily available thiazolium salts is described. The general reaction successfully utilizes acylsilanes as carbonyl anion precursors and is tolerant of a range of structural diversity on the acylsilane or imine electrophile. The overall reaction utilizes easily available precursors and directly accesses protected alpha-amino ketones in the correct oxidation state.
Few-body physics with ultracold atomic and molecular systems in traps

Few-body physics has played a prominent role in atomic, molecular and nuclear physics since the early days of quantum mechanics. It is now possible—thanks to tremendous progress in cooling, trapping and manipulating ultracold samples—to experimentally study few-body phenomena in trapped atomic and molecular systems with unprecedented control. This review summarizes recent studies of few-body phenomena in trapped atomic and molecular gases, with an emphasis on small trapped systems. We start by introducing the free-space scattering properties and then investigate what happens when two particles, bosons or fermions, are placed in an external confinement. Next, various three-body systems are treated analytically in limiting cases. Our current understanding of larger two-component Fermi systems and Bose systems is reviewed, and connections with the corresponding bulk systems are established. Lastly, future prospects and challenges are discussed. Throughout this review, commonalities with other systems such as nuclei or quantum dots are highlighted.
Quantum key distribution without reference frame alignment: Exploiting photon orbital angular momentum

Abstract We present a new implementation of the BB84 quantum key distribution (QKD) protocol that employs a d -dimensional Hilbert space spanned by spatial modes of the propagating beam that have a definite value of orbital angular momentum. Each photon carries log d bits of information, increasing the key generation rate of the protocol. The states used in the transmission part of the protocol are invariant under rotations about the propagation direction, making this implementation independent of the alignment between the reference frames of the sender and receiver, and hence appealing for free space QKD. The protocol still works when these reference frames rotate with respect to each other.
A novel N-dealkylation reaction of N,N-dialkylarylcarboxamides promoted by electron transfer from alkali metals

Abstract Reactions of some N,N -dialkylarylcarboxamides with either lithium or sodium metals in dry tetrahydrofuran (THF) promoted by ultrasound waves afforded the corresponding N -monoalkylarylcarboxamides in good yields. In the cases of N,N -diethylarylcarboxamides the products obtained were derived from coupling reactions rather than from N -dealkylation reactions.
Monitoring large enrichment plants using thermal imagery from commercial satellites: A case study

Thermal imagery from currently operating commercial satellites is an interesting candidate technology for monitoring certain types of fissile material production sites. Potential applications include the Fissile Material Cutoff Treaty (FMCT) or a Fissile Material Production Moratorium. To help determine the capabilities and limitations of such imagery as a monitoring tool, I have examined archived LANDSAT‐5 images of the Portsmouth Gaseous Diffusion Plant, a large U.S. uranium‐enrichment facility in Ohio. My analysis indicates that large‐scale gaseous diffusion plants (GDPs) can very likely be recognized as operational with thermal imagery throughout most of the year in clear weather conditions. It may also be possible to identify certain other large‐scale changes in operations, such as the shut‐down of a single process building in a plant, by comparing rooftop temperatures of neighboring operational process buildings. However, uncertainties in the current data set prevent a definitive conclusion regardin...
MR: macaulay resultant package for maple

The software package MR for Maple, Versions 7 and 8, contains an implementation of Macaulay's algorithm for computing the dense multi-variable resultant ([?], [?]) of a list of multivariate polynomials. An extended list of some of the features is:• Designed independently from the coefficient ring of the input polynomials.• Optimized for polynomials with coefficients being integer polynomials.• Optionally computes generalized characteristic polynomials.• Optionally self-profiling (timing, tracing).• Well integrated with Maple's Linear Algebra package.• Designed to emulate overloading, according to the type of the input, of the main sub-functions, while not sacrificing efficiency.It is important to point out that there are other resultant packages available for Maple (see e.g. [?], [?], [?]). However, they do not provide the full range of features of the current package, MR, and they are not designed for the most recent versions of Maple. Therefore the author believes that the current package is of great interest to the symbolic computation community.Usage: We briefly describe how the package MR is to be used in Maple. The main function, exported by the package MR, is called asMR:- MResultant (plist, vlist, options);The input argument "plist" is a list of not necessarily homogeneous polynomials. The variables of these polynomials are contained in the list "vlist". The symbol "options" stands for a sequence of optional arguments. These optional arguments are described in detail in http://minimair.org/MR.mpl. If called without optional arguments, the main function returns the Macaulay (multi-variable) resultant of the polynomials in "plist" with respect to the variables in "vlist".
The power of temporal proofs

Abstract Some methods for reasoning about concurrent programs and hardware devices have been based on proof systems for temporal logic. Unfortunately, all effective proof systems for temporal logic are incomplete for the standard semantics, in the sense that some formulas hold in every intended model but cannot be proved. We evaluate and compare the power of several proof systems for temporal logic. Specifically, we relate temporal systems to classical systems with explicit time parameters. A typical temporal system turns out to be incomplete in a strong sense; we exhibit a short, valid formula it fails to prove. We suggest the addition of new rules to define auxiliary predicates. With these rules, we obtain nonstandard soundness and completeness results. In particular, one of the simple temporal systems we describe is as powerful as Peano Arithmetic.
Entanglement growth during thermalization in holographic systems

We derive in detail several universal features in the time evolution of entanglement entropy and other nonlocal observables in quenched holographic systems. The quenches are such that a spatially uniform density of energy is injected at an instant in time, exciting a strongly coupled conformal field theory which eventually equilibrates. Such quench processes are described on the gravity side by the gravitational collapse of a thin shell that results in a black hole. Various nonlocal observables have a unified description in terms of the area of extremal surfaces of different dimensions. In the large distance limit, the evolution of an extremal surface, and thus the corresponding boundary observable, is controlled by the geometry around and inside the event horizon of the black hole, allowing us to identify regimes of pre-local-equilibration quadratic growth, post-local-equilibration linear growth, a memory loss regime, and a saturation regime with behavior resembling those in phase transitions. We also discuss possible bounds on the maximal rate of entanglement growth in relativistic systems.
Desirable excitation patterns for tapered wigglers

Abstract Angular and displacement errors associated with excitation patterns of tapered wigglers will be discussed, and patterns will be described that do not lead to such errors even when the energy of the electrons changes along the length of the wiggler, and when the real excitation is different from the ideal excitation because of systematic iron saturation.
Search, Sticky Prices, and Inflation

This paper examines equilibrium in a deflationary environment, in a market with free entry where consumers search and firms set prices on individual units of the commodity. Prices attached to newly produced goods are continuously adjusted. Prices attached to previously produced goods can only be changed at a cost. Deflation cuts into the market power created by the need to search for the good. Thus consumers' welfare is inverse u-shaped in deflation.
Clinical predictors of mandibular fractures

To evaluate the diagnostic accuracy of clinical signs and symptoms of mandibular fracture, a prospective study of emergency department patients presenting with mandibular trauma was undertaken. Patients with airway compromise, who were edentulous, or could not cooperate with the physical examination were excluded. Over a 1-year period, 119 patients were studied. The presence of malocclusion, trismus, facial asymmetry, or a positive result on the tongue blade test (inability to grasp and hold a tongue blade between the teeth) was significantly associated with a mandibular fracture. Malocclusion and facial asymmetry were strong predictors of fracture, and a negative result on the tongue blade test was a strong predictor of nonfracture.
The Pulse Scale Conjecture and the Case of BATSE Trigger 2193

The pulses that compose gamma-ray bursts (GRBs) are hypothesized to have the same shape at all energies, differing only by scale factors in time and amplitude. This "pulse scale conjecture" is confirmed here between energy channels of the dominant pulse in GRB 930214c (BATSE trigger 2193), the single most fluent single-pulsed GRB that occurred before 1998 May. Furthermore, pulses are hypothesized to start at the same time, independent of energy. This "pulse start conjecture" is also confirmed in GRB 930214c. Analysis of GRB 930214c also shows that, in general, higher energy channels show shorter temporal scale factors. Over the energy range 100 keV-1 MeV, it is found that the temporal scale factors between a pulse measured at different energies are related to that energy by a power law, possibly indicating a simple relativistic mechanism is at work. To test robustness, the pulse start and pulse scale conjectures were also tested on the four next most fluent single-pulse GRBs. Three of the four clearly passed, with a second smaller pulse possibly confounding the discrepant test. Models where the pulse rise and decay are created by different phenomena and do not typically predict pulses that satisfy both the pulse start conjecture and the pulse scale conjecture, unless both processes are seen to undergo common time dilation.
Approximation algorithms for multiple sequence alignment under a fixed evolutionary tree

We consider the problem of aligning sequences related by a given evolutionary tree: given a fixed tree with its leaves labeled with sequences, find ancestral sequences to label the internal nodes so as to minimize the total cost of all the edges in the tree. The cost of an edge is the edit distance between the sequences labeling its endpoints. In this paper, we consider the case when the given tree is a regular d-ary tree for some fixed d and provide a d+1/d−1-approximation algorithm for this problem that runs in time O(d(2kn) d + n2k2d) where k is the number of leaves in the tree and n is the maximum length of any of the sequences labeling the leaves.
Non-detection of a statistically anisotropic power spectrum in large-scale structure

We search a sample of photometric luminous red galaxies (LRGs) measured by the Sloan Digital Sky Survey (SDSS) for a quadrupolar anisotropy in the primordial power spectrum, in which P(k) is an isotropic power spectrum P[overbar](k) multiplied by a quadrupolar modulation pattern. We first place limits on the 5 coefficients of a general quadrupole anisotropy. We also consider axisymmetric quadrupoles of the form P(k) = P[overbar](k){1+g_*[k[circuflex] ∙ n[circumflex]^2 − (1/3)]} where n[circumflex] is the axis of the anisotropy. When we force the symmetry axis n[circumflex] to be in the direction (l,b) = (94°,26°) identified in the recent Groeneboom et al. analysis of the cosmic microwave background, we find g* = 0.006±0.036 (1σ). With uniform priors on n[circumflex] and g_* we find that −0.41 < g_* < +0.38 with 95% probability, with the wide range due mainly to the large uncertainty of asymmetries aligned with the Galactic Plane. In none of these three analyses do we detect evidence for quadrupolar power anisotropy in large scale structure.
Superconductivity and ferromagnetism from effective mass reduction

Abstract Within a simple model Hamiltonian, both superconductivity and metallic ferromagnetism can be understood as arising from lowering of kinetic energy as the ordered state develops, due to a reduction in the carriers effective mass, or equivalently, a bandwidth expansion. Experimental manifestation of this physics has been detected in both high Tc superconductors and large magnetoresistance ferromagnets, as an anomalous transfer of spectral weight in optical absorption from high to low frequencies as the ordered state develops. It is proposed that this general principle is common to the essential physics of superconductivity and ferromagnetism in nature, and hence that these effects in optical properties, although often smaller in magnitude, should exist in all superconductors and metallic ferromagnets.
Synthesis of prenylated peptides and peptide esters.

Modification of the cysteine sulfur in peptides and proteins to a thioether is a recently described posttranslational event that results in the incorporation of farnesyl and geranylgeranyl moieties. The increased lipophilicity accompanying these modifications often causes localization of the resulting protein to the membrane and may be essential for biological activity. Methods are described to chemically and biochemically synthesize farnesylated and geranylgeranylated peptides and proteins from microgram to gram quantities. Conditions for thioalkylation include acidic, neutral, and basic media. The ability to readily form peptidylthioethers will greatly facilitate studies of biologically important proteins and peptides containing isoprenyl moieties. © 1997 John Wiley & Sons, Inc. Biopoly 43: 3–14, 1997
OneBusAway Multi-Region - Rapidly Expanding Mobile Transit Apps to New Cities

Real-time transit information offers many benefits to transit riders, including reduced wait times and increased customer satisfaction. However, offering real-time transit services has been challenging for many transit agencies. While mobile applications (apps) have emerged as a preferred dissemination method for real-time information, it is typically cost-prohibitive for transit agencies to fund custom development of native mobile apps for all popular smartphone platforms. Third-party developers can offer services if an agency openly shares real-time data, but these individuals are volunteers whose priorities and deadlines may not be the same as the agency’s. As a result, few cities have full app portfolios that cover all smartphone platforms. This paper presents the OneBusAway multi-region project, a collaborative effort that is enabling the rapid expansion of native mobile transit apps to new cities. OneBusAway is an open-source transit information system that has provided real-time transit services to the Puget Sound (Washington) area since 2008. The new OneBu sAway multi-region feature expands the coverage of the existing Android, iPhone, Windows Phone, and Windows 8 apps for OneBusAway to new cities, including Tampa and Atlanta. The multi-region system architecture, collaborative design and development process, and lessons learned from this ground-breaking project are discussed. The fundamental shift from proprietary to open-source software in the transit industry that has made this type of project possible also is examined.
Numerical Approximation of Probability Mass Functions via the Inverse Discrete Fourier Transform

First passage distributions of semi-Markov processes are of interest in fields such as reliability, survival analysis, and many others. Finding or computing first passage distributions is, in general, quite challenging. We take the approach of using characteristic functions (or Fourier transforms) and inverting them to numerically calculate the first passage distribution. Numerical inversion of characteristic functions can be unstable for a general probability measure. However, we show they can be quickly and accurately calculated using the inverse discrete Fourier transform for lattice distributions. Using the fast Fourier transform algorithm these computations can be extremely fast. In addition to the speed of this approach, we are able to prove a few useful bounds for the numerical inversion error of the characteristic functions. These error bounds rely on the existence of a first or second moment of the distribution, or on an eventual monotonicity condition. We demonstrate these techniques with two examples.
Precise Chandra Localization of the Soft Gamma-Ray Repeater SGR 1806–20

We present observations of the soft γ-ray repeater SGR 1806-20 taken with the Chandra X-Ray Observatory. We identify the X-ray counterpart of SGR 1806-20 based on detection of 7.5 s pulsations. Using three unrelated X-ray sources (and USNO stars) as position references, we are able to determine that the SGR is at α2000 = 18h08m3932 and δ2000 = -20°24'395, with rms uncertainty of 03 in each coordinate. We find that SGR 1806-20 is located within the 1 σ error region determined by Interplanetary Network data and is 14'' ± 05 distant from the nonthermal core of SNR G10.0-0.3, excluding SGR 1806-20 as the origin of the core. We see evidence of a significant deviation of the spin-down of SGR 1806-20 from its long-term trend, demonstrating erratic spin-down behavior in this source similar to that seen in other SGRs. Finally, we show that there is a broad X-ray halo surrounding SGR 1806-20 out to radii ~1' due to scattering in the interstellar medium.