cssi/SciSciGPT-SciSciNet huggingface dataset:
A dynamic technique for measurements of thermophysical properties at high temperatures

A technique is described for the dynamic measurement of selected thermophysical properties of electrically conducting solids in the range 1500 K to the melting temperature of the specimen. The technique is based on rapid resistive selfheating of the specimen from room temperature to any desired high temperature in less than 1 s by the passage of an electrical current pulse through it and on measuring the pertinent quantities, such as current, voltage, and temperature, with millisecond resolution. The technique was applied to the measurement of heat capacity, electrical resistivity, hemispherical total emissivity, normal spectral emissivity, thermal expansion, temperature and energy of solid-solid phase transformations, melting temperature, and heat of fusion. Two possible options for the extension of the technique to measurements above the melting temperature of the specimen are briefly discussed. These options are: (1) submillisecond heating of the specimen and performance of the measurements with microsecond resolution, and (2) performance of the experiments in a near-zero-gravity environment with millisecond resolution.
Probability distributions for one component equations with multiplicative noise

Abstract Systems described by equations involving both multiplicative and additive noise are common in nature. Examples include convection of a passive scalar field, polymers in turbulent flow, and noise in dye lasers. In this paper the one component version of this problem is studied. The steady state probability distribution is classified into two different types of behavior. One class has power law tails and the other is of the form of an exponential to a power law. The value of the power law exponent is determined analytically for models having colored gaussian noise. It is found to only depend on the power spectrum of the noise at zero frequency. When non-gaussian noise is considered it is shown that stretched exponential tails are possible. An intuitive understanding of the results is found and makes use of the Lyapunov exponents for these systems.
Second primary tumors in patients with cutaneous malignant melanoma.

BACKGROUND Several studies report coexistent or subsequent primary tumors (SPT) among patients with malignant melanoma (MM), with the rate of incidence ranging from 1.5–20% depending on the sample size and the length and completeness of follow-up. METHODS The authors followed a cohort of patients with cutaneous MM who were diagnosed and treated at the City of Hope National Medical Center to determine the incidence rate of SPT and associated risk factors. Five hundred eighty-five patients (median age at diagnosis, 43 years) were diagnosed and treated for MM between 1952 and 1996 and followed for a median of 6.5 years (range, 0.0–37.0 years). Ninety-six percent of the cohort had been treated by surgery alone. RESULTS Thirty-seven patients developed an SPT. These included skin cancers (n = 23), carcinoma of the urinary bladder, breast carcinoma, and lymphoma (n = 3 each), lung carcinoma and prostate carcinoma (n = 2 each), and cervical carcinoma (n = 1). The estimated cumulative rate of incidence after MM was 5% at 5 years for any SPT, 3.7% for a second skin cancer, and 1.1% for a second solid tumor. Overall, the current cohort of MM patients was found to be at an increased risk for developing a subsequent melanoma (standardized incidence ratio [SIR], 4.5; 95% confidence interval [95% CI], 1.2–10.0) when compared with the general population. Older men (age > 50 years at the time of diagnosis of MM) were at an increased risk of developing subsequent bladder carcinoma (SIR, 6.4; 95% CI, 1.2–15.7). CONCLUSIONS Patients diagnosed with MM are at an increased risk of developing subsequent MM and bladder carcinoma. Issues to be addressed in future studies include interactions between environmental exposures and genetic susceptibility and the identification of individuals at increased risk. Cancer 1999;86:2014–20. © 1999 American Cancer Society.
Microcrack Nucleation and Crack Propagation in Equiaxed γ TiAl

To gain a better understanding of the ductility limitations in TiAl alloys, the mechanisms involved in deformation strain transfer and/or microcrack initiation at grain boundaries have been examined in an equiaxed near-γ alloy. These studies have been carried out on both in-situ and ex-situ deformed bulk samples using scanning electron microscopy (SEM) techniques for both orientation analysis and deformation defect imaging. Selected area electron channeling patterns (SACPs) have allowed determination of grain orientations, eliminating ambiguity between the a and c axes. Deformation twins and dislocations have been imaged in the bulk samples using electron channeling contrast imaging (ECCI). A combination of ECCI contrast analysis and trace analysis based on orientations determined from SACP has allowed identification of the active deformation systems. Microcracks have been found to initiate at γ-γ boundaries as a result of an inability to adequately transfer twin strain from grain to grain. Once initiated, cracks propagate through cleavage and re-nucleation of grain boundary microcracks in front of the advancing crack. A geometric based predictive factor has been developed that accounts for microcrack initiation at γ-γ boundaries based in deformation twinning and strain accommodation by ordinary dislocations.
Truthful germs are contagious: A local-to-global characterization of truthfulness

Abstract We study the question of which social choice functions from an abstract type space to a set of outcomes are truthful, i.e., implementable by truthful mechanisms, when utilities are quasi-linear. For convex domains, our main theorem characterizes truthful social choice functions as those satisfying two properties: local weak monotonicity and vortex-freeness. The first of these constrains the function values at any two sufficiently proximal points, while the second asserts that its line integrals around sufficiently small triangular loops must vanish. The characterization implies a local-to-global principle that allows one to deduce truthfulness of a function from its behavior on arbitrarily small neighborhoods of each point. Other consequences include a simple alternate derivation of the Saks–Yu Theorem that weak monotonicity characterizes truthfulness of functions having a convex domain and finite range, and a sufficient condition for constructing truthful functions by “stitching together” truthful subfunctions on different subsets of the domain.
Non-identical particle correlation analysis as a probe of transverse flow

Abstract Non-identical two particle correlation functions probe asymmetries between the average space-time emission points of different particle species. The system collective expansion would produce such asymmetry because massive particles, such as protons, are on average more pushed towards the edge of the system, than lighter ones, i.e. pions. Measuring pion-kaon, pion-proton and kaon-proton correlation functions, using the STAR detector, we show that the data are consistent with the effect of transverse flow in Au Au collisions at S N N = 130 GeV.
C*-actions of r-discrete groupoids and inverse semigroups

Groupoid actions on C*-bundles and inverse semigroup actions on C *-algebras are closely related when the groupoid is r -discrete.
Dynamics and control of the activated sludge wastewater process

The dynamics of the activated sludge process are governed under certain conditions by interactions between the reactor and settler through sludge recycle. Settler underloading can lead to extremely sluggish system response, indicating that effective sludge height regulation is an important control objective. This objective may be in conflict with the need to maintain small variations in reactor solids concentration. An effective compromise can be achieved by using ratio control on both sludge recycle and settler underflow. This control policy does not require sludge storage.
Quantum annealing: A new method for minimizing multidimensional functions

Abstract Quantum annealing is a new method for finding extrema of multidimensional functions. Based on an extension of classical, simulated annealing, this approach appears robust with respect to avoiding local minima. Further, unlike some of its predecessors, it does not require an approximation to a wavefunction. We apply the technique to the problem of finding the lowest energy configurations of Lennard-Jones clusters of up to 19 particles (roughly 105 local minima). This early success suggests that this method may complement the widely implemented technique of simulated annealing.
The largest and the smallest fixed points of permutations

We give a new interpretation of the derangement numbers d"n as the sum of the values of the largest fixed points of all non-derangements of length n-1. We also show that the analogous sum for the smallest fixed points equals the number of permutations of length n with at least two fixed points. We provide analytic and bijective proofs of both results, as well as a new recurrence for the derangement numbers.
A semi-analytical approach to non-linear shock acceleration

Abstract Shocks in astrophysical fluids can generate suprathermal particles by first order (or diffusive) Fermi acceleration. In the test particle regime there is a simple relation between the spectrum of the accelerated particles and the jump conditions at the shock. This simple picture becomes complicated when the pressure of the accelerated particles becomes comparable with the pressure of the shocked fluid, so that the non-linear backreaction of the particles becomes non-negligible and the spectrum is affected in a substantial way. Though only numerical simulations can provide a fully self-consistent approach, a more direct and easily applicable method would be very useful, and would allow to take into account the non-linear effects in particle acceleration in those cases in which they are important and still neglected. We present here a simple semi-analytical model that deals with these non-linear effects in a quantitative way. This new method, while compatible with the previous simplified results, also provides a satisfactory description of the results of numerical simulations of shock acceleration.
Ring opening/fragmentation of dihydropyrones for the synthesis of homopropargyl alcohols.

Ring-opening/C–C bond cleavage reactions induced by nucleophilic addition of methyl Grignard to 5,6-dihydro-2-pyrone (DHP) triflates 1 furnish homopropargyl alcohols (1 → 2) stereospecifically with respect to the stereochemistry of 1. Carbonyl extrusion from DHP triflates provides a unified and operationally simple strategy for preparing chiral homopropargyl alcohols.
Biomimetic polyene cyclizations. Synthesis of racemic 19‐norprogesterone

The aim of this study was to apply biomimetic cyclization strategy to a total synthesis of racemic 19-norprogesterone (8). Treatment of enone 1 with lithium aluminium hydride in ether afforded trienynol 2 which was cyclized with trifluoroacetic acid in methylene chloride containing ethylene carbonate to give ketone 4 as a 76/24 mixture of the 17β/17α epimers in 52% yield. Conversion of 4 to DL-19-norprogesterone (8) was effected in 68% yield by ozonolysis (to give 6) followed by cyclodehydration.
Computations of Steady and Unsteady Low-Speed Turbulent Separated Flows

Numerical computations are presented for two-dimensional steady and unsteady separated flows. The first case is a low-speed, converging-diverging duct with a rapid expansion, creating a large separated flow region. The second case is the Massachusetts Institute of Technology flapping foil experiment, where a stationary hydrofoil is subject to gust loading. Numerical solutions are obtained by solving the incompressible Navier-Stokes equations. These equations are solved in a time accurate manner using the method of artificial compressibility. The Johnson and King turbulence model is employed for modeling the turbulent flow. Modifications to the model are suggested that take into account the normal stress production of energy and the strong adverse pressure gradient associated with separating flows. The performance of the Johnson and King model and its modifications are studied for both steady and unsteady flow conditions
The unique cosmic-ray history of the Malakal chondrite

Cosmogenic radionuclides, including Na-22, Al-26, and Mn-54, were measured in a sample of the recently-fallen Malakal hypersthene chondrite. The high Al-26 activity, 79 plus or minus 2 dpm/kg, greatly exceeds the levels expected from elemental production rates, shielding considerations, or comparisons with other ordinary chondrites, and can only be explained by exposure to a uniquely high cosmic-ray flux. Calculations including noble gas, H-3, and Mn-53 data from other laboratories require a two-stage irradiation. Malakal's most probable history is: exposure in excess of 4 m.y. to an effective cosmic-ray flux approximately three times that experienced by other chondrites, an orbit change (very possibly caused by a collision), and a final period of about 2 m.y. during which it was exposed to a normal cosmic-ray flux.
A Low-Light-Level Objective Lens with Integral Laser Channel

A high performance, f/1.5 objective lens of 229 mm (9 inches) focal length has been designed and produced for use in a variety of military low light level systems. The latest version of this lens has an integral coaxial 10X beam expander for a 1.06//m laser beam. This allows the lens to be used in a laser rangefinder/target designator role as well as to produce an ambient light image of a 20° field of view for intensification in a direct-view periscope. In this paper, the configuration and optical performance of this new objective lens are described, and the means used to solve some of the unique problems associated with transmission of the laser beam are discussed.
Factorization and reflexivity on Fock spaces

The framework of the paper is that of the full Fock space\(\mathcal{F}^2 (\mathcal{H}_n )\) and the Banach algebraF∞ which can be viewed as non-commutative analogues of the Hardy spacesH2 andH∞ respectively.
How does connectivity between cortical areas depend on brain size? Implications for efficient computation

A formula for an average connectivity between cortical areas in mammals is derived. Based on comparative neuroanatomical data, it is found, surprisingly, that this connectivity is either only weakly dependent or independent of brain size. It is discussed how this formula can be used to estimate the average length of axons in white matter. Other allometric relations, such as cortical patches and area sizes vs. brain size, are also provided. Finally, some functional implications, with an emphasis on efficient cortical computation, are discussed as well.
Implementing a large office automation system: how to make it work

This paper discusses the implementation of a large office automation system to be used by nondata processing as well as data processing staff, i.e., the knowledge worker. At its completion the system will encompass more than 1,000 terminals (one terminal per office). The paper covers the nature of the basic system, IBM's Professional Office System (PROFS), what it does, how it functions, the extent of use, and how to encourage potential users to use it. The paper reviews training procedures from one-on-one to higher ratios and the reasoning behind them, and goes over in detail the nature of the "innovation" curve. Also reviewed are the computer performance and the Local Area Network (broadband with Sytek bus interface units). We currently serve more than 500 users with around 300 terminals already distributed.
Hubbert’s peak, the coal question, and climate change

There is a vigorous debate now about whether oil, natural gas, and coal resources will be sufficient in the future. At the same time, there is an intense effort to predict the changes in climate that will result from consuming these fossil fuels. There has been surprisingly little effort to connect these two. Do we have a fossil-fuel supply problem? Do we have a climate-change problem? Do we have both? Which comes first? We will see that the trend for future fossil-fuel production is less than what is assumed in the United Nations climate-change assessments. The implication is that an understanding of producer limitations could help us do a better job of predicting climate change. We will also see that the time scale for exhausting fossil fuels is much smaller than that for global temperature change. This means that it is critical to reduce the total fossil-fuel production, not just slow it down. One possible approach for reducing total production would be to establish fossil-fuel preserves on federal lands that would be off limits for new leases for drilling and mining.
Total Synthesis of (+)-Thiazinotrienomycin E

[formula: see text] The first total synthesis of (+)-thiazinotrienomycin E (1), member of a novel class of cytotoxic ansamycin antibiotics, has been achieved. The synthesis features a highly efficient construction of the aromatic fragment 3 incorporating TBS protection of the aniline, a significantly improved synthesis of (-)-19, an intermediate employed in our trienomycins A and F total syntheses, application of the Kocienski modified Julia protocol to elaborate the E,E,E-triene subunit, an efficient union of 3 and (+)-4, and Mukaiyama macrolactamization to access the thiazinotrienomycin macrolide.
Production of an accelerated oxygen-14 beam

Abstract BEARS is an ongoing project to provide a light-ion radioactive-beam capability at the 88-Inch Cyclotron at LBNL. Light radioactive isotopes are produced at a 10 MeV proton medical cyclotron, transported 350 m via a high-speed gas transport capillary, cryogenically separated, and injected into the 88-Inch Cyclotron’s ion source. The first radioactive beam successfully accelerated was carbon-11 and beams of intensity more than 10 8 ions/s have been utilized for experiments. Development of oxygen-14 as the second BEARS beam presented considerable technical challenges, both due to its short half-life of 71 s and the radiation chemistry of oxygen in the target. The usual techniques developed for medical uses of oxygen-15 involve the addition of significant amounts of carrier oxygen, something that would overload the ion source. As a solution, oxygen-14 is produced as water in a carrier-free form, and is chemically converted in two steps to carbon dioxide, a form readily usable by the BEARS. This system has been built and is operational, and initial tests of accelerating an oxygen-14 beam have been performed.
Multiple Recurrence in Quasirandom Groups

We establish a new mixing theorem for quasirandom groups (finite groups with no low-dimensional unitary representations) G which, informally speaking, asserts that if g, x are drawn uniformly at random from G, then the quadruple (g, x, gx, xg) behaves like a random tuple in G 4, subject to the obvious constraint that gx and xg are conjugate to each other. The proof is non-elementary, proceeding by first using an ultraproduct construction to replace the finitary claim on quasirandom groups with an infinitary analogue concerning a limiting group object that we call an ultra quasirandom group, and then using the machinery of idempotent ultrafilters to establish the required mixing property for such groups. Some simpler recurrence theorems (involving tuples such as (x, gx, xg)) are also presented, as well as some further discussion of specific examples of ultra quasirandom groups.
Pediatric cardiac tumors: a 45-year, single-institution review

Background:Cardiac tumors in children are rare. Of the cases reported in the literature, nearly all are benign and managed conservatively.Methods:This is a retrospective, observational study of pediatric patients <18 years who presented for surgical evaluation of a cardiac tumor, between 1969 and 2014 at a tertiary care children’s hospital. Presentation, pathology, management, and outcomes were evaluated.Results:Over the last 45 years, 64 patients were evaluated for surgical resection of a cardiac tumor. Rhabdomyoma was the most common neoplasm (58%), and 17% of the tumors had malignant pathologies. While 42% of benign cardiac neoplasms required surgical intervention for significant hemodynamic concerns, 73% of malignant neoplasms underwent radical excision, if possible, followed by adjuvant chemotherapy. Despite a 37% mortality in patients with malignant pathology, an aggressive surgical approach can yield long-term survival in some patients. There were no deaths among patients with benign tumors and 17%...
Direct numerical simulation of transition and turbulence in a spatially evolving boundary layer

Abstract A high-order-accurate finite-difference approach to direct simulations of transition and turbulence in compressible flows is described. The technique involves using a zonal grid system, upwind-biased differences for the convective terms, central differences for the viscous terms, and an iterative-implicit time-integration scheme. The integration method is used to compute transition and turbulence on a flat plate. The main objective is to determine the computability of such a flow with currently available computer speeds and storage and to address some of the algorithmic issues such as accuracy, inlet and exit boundary conditions, and grid-point requirements. A novel feature of the present study is the presence of high levels of broad band freestream fluctuations. The computed data are in qualitative agreement with experimental data (from experiments on which the computation is modeled). The computational results indicate that the essential features of the transition process have been captured. Additionally, the finite-difference method presented in this study can, in a straightforward manner, be used for complex geometries.
The Acceptability of Regression Solutions: Another Look at Computational Accuracy

Abstract Longley [10] proposed a set of data for use in testing regression programs. This paper shows that the numerically accurate solution in this example was probably an unreasonable estimate of the regression coefficients. This is true because the accuracy of the data and appropriateness of the model may affect the solution more than the computational method. An easily computed index is derived that can be used to indicate such computational instability. The basic conclusion is that a concern about highly accurate computational methods must be tempered with a concern for whether the data are accurate enough to make the results meaningful.
The CRT display subsystem of the IBM 1500 instructional system

The IBM 1500 Instructional System is an experimental system for computer-assisted instruction, designed to administer individual programmed lessons to 32 students at once. Working through one or more teaching devices at his own instructional station, a student may follow a course quite different from, and independent of, lessons presented at other stations. Instructional programs stored in central files control lesson content, sequence, timing, and audio-visual medium, varying all of these according to the student's responses.
Quantum decision-maker

Abstract A quantum device simulating human decision making process is introduced. It consists of quantum recurrent nets generating stochastic processes which represent the motor dynamics, and of classical neural nets describing evolution of probabilities of these processes which represent the mental dynamics. The autonomy of the decision making process is achieved by a feedback from mental to motor dynamics which changes the stochastic matrix based upon the probability distributions. This feedback replaces an unavailable external information by an internal knowledgebase stored in the mental model in the form of probability distributions. As a result, the coupled motor-mental dynamics is described by a nonlinear version of Markov chains which can decrease entropy without an external source of information. Applications to common sense based decisions as well as to evolutionary games are discussed.
Advances in ambient temperature secondary lithium cells

The goal of the NASA/OAST sponsored program on the development of ambient-temperature secondary lithium cells for future space applications is to develop cells with a 100 W h/kg specific energy and capable of 1000 cycles at 50-percent depth of discharge. This paper examines the performance potentials of Li-TiS2, Li-MoS3, Li-V6O13, and Li-NbSe3 electrochemical systems at ambient temperature, together with cycle life and safety characteristics. Of these four, the Li-TiS2 system was found to be the most promising in terms of achievable specific energy and cycle life. Major advances made on the development of secondary lithium cells, which are in the areas of cathode processing technology, mixed solvent electrolytes, and cell assembly, are summarized.
SPRINT: a direct approach to list processing languages

Most current list processing languages such as LISP and IPL-V operate in an indirect manner, i.e., during execution of a program written in these languages, the basic operations do not deal directly with data but rather with addresses which point to the data, making it awkward to perform operations at the input syntax level.
Temperature and high strain rate dependence of tensile deformation behavior in single-crystal iron from dislocation dynamics simulations

Abstract We conduct dislocation dynamics simulations of Fe periodic single crystals under tensile load at several high strain rates and temperatures. The simulations are connected to the atomistic scale via recently developed, temperature-dependent dislocation mobility relations. We explore strain rates from 10 4 to 10 6 s - 1 at temperatures of 100, 300 and 600 K. We compute the flow stress as a function of strain rate and temperature, and find very good agreement with experimental data for Fe, suggesting that strain hardening is the dominant materials response mechanism in the range of conditions explored here.
Distributed Lossy Averaging

In this paper, an information theoretic formulation of the distributed averaging problem previously studied in computer science and control is presented. We assume a network with m nodes each observing a white Gaussian noise (WGN) source. The nodes communicate and perform local processing with the goal of computing the average of the sources to within a prescribed mean squared error distortion. The network rate distortion function R* (D) for a two-node network with correlated Gaussian sources is established. A general cutset lower bound on R*(D) is established and shown to be achievable to within a factor of 2 via a centralized protocol over a star network. A lower bound on the network rate distortion function for distributed weighted-sum protocols, which is larger in order than the cutset bound by a factor of log m, is established. An upper bound on the network rate distortion function for gossip-base weighted-sum protocols, which is only log log m larger in order than the lower bound for a complete graph network, is established. The results suggest that using distributed protocols results in a factor of log m increase in order relative to centralized protocols.
Sparse monolithic compliant mechanisms using continuum structural topology optimization

A formulation for design of continuous, hinge-free compliant mechanisms is developed and examined within a continuum structural topology optimization framework. The formulation makes use of two distinctly different sets of springs, the first of which are artificial springs of relatively large stiffness attached to the input and output ports of the mechanism model, and the second of which are springs attached only to the output port with smaller stiffnesses that represent the resistance of the workpiece as it is manipulated by the mechanism. The proposed formulation involves solving two nested optimization problems. In the inner problem the arrangement of a constrained amount of structural material is optimized to maximize the mechanism's mutual potential energy in response to a force loading at the input port while working against the stiff artificial springs on the input and output ports. As the relative stiffness of the artificial springs increases, the material continuity of the mechanism also increases to the point where de facto ‘hinge’ regions are eliminated. In the outer problem, the artificial springs are removed and one solves for an appropriate amount of structural material that yields the desired finite deformation compliance characteristics of the mechanism when working against the real workpiece resistance. Different aspects of the proposed formulation are demonstrated on a number of examples and discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Lower bounds on nonnegative rank via nonnegative nuclear norms

The nonnegative rank of an entrywise nonnegative matrix $$A \in \mathbb {R}^{m \times n}_+$$A?R+m×n is the smallest integer $$r$$r such that $$A$$A can be written as $$A=UV$$A=UV where $$U \in \mathbb {R}^{m \times r}_+$$U?R+m×r and $$V \in \mathbb {R}^{r \times n}_+$$V?R+r×n are both nonnegative. The nonnegative rank arises in different areas such as combinatorial optimization and communication complexity. Computing this quantity is NP-hard in general and it is thus important to find efficient bounding techniques especially in the context of the aforementioned applications. In this paper we propose a new lower bound on the nonnegative rank which, unlike most existing lower bounds, does not solely rely on the matrix sparsity pattern and applies to nonnegative matrices with arbitrary support. The idea involves computing a certain nuclear norm with nonnegativity constraints which allows to lower bound the nonnegative rank, in the same way the standard nuclear norm gives lower bounds on the standard rank. Our lower bound is expressed as the solution of a copositive programming problem and can be relaxed to obtain polynomial-time computable lower bounds using semidefinite programming. We compare our lower bound with existing ones, and we show examples of matrices where our lower bound performs better than currently known ones.
Gauging internal fermionic symmetries and spin-3/2 fields

Field theoretic models possessing a global internal fermionic shift symmetry are considered. When such a symmetry is realized locally, spin-3/2 fields appear naturally as gauge fields. Implementation of the gauging procedure requires not only the usual replacement of ordinary derivatives by covariant derivatives containing the spin-3/2 fields, but also the inclusion of additional monomials. The Higgs mechanism and the high energy Nambu–Goldstone fermion equivalence theorem are explicitly demonstrated.
The effect of solute on the homogeneous crystal nucleation frequency in metallic melts

A complete calculation that extends the classical theory for crystal nucleation in pure melts to binary alloys has been made. Using a regular solution model, approximate expressions have been developed for the free energy change upon crystallization as a function of solute concentration. They are used, together with model-based estimates of the interfacial tension, to calculate the nucleation frequency. The predictions of the theory for the maximum attainable undercooling are compared with existing experimental results for non-glass forming alloys. The theory is also applied to several easy glass-forming alloys (Pd-Si, Au-Si, Fe-B) for qualitative comparison with the present experimental experience on the ease of glass formation, and for assessment of the potential for formation of the glass in bulk.
Bank Representation in Low-Income and Minority Urban Communities:

The author of this article examines the empirical support for the propositions that bank branches are significantly underrepresented in low-income and minority urban communities and that the proble...
Deformed Heisenberg algebra: origin of q-calculus

The intimate connection between q-deformed Heisenberg uncertainty relation and the Jackson derivative (JD) based on q-basic numbers has been noted in the literature. The purpose of this work is to establish this connection in a clear and self-consistent formulation and to show explicitly how the JD arises naturally. We utilize a holomorphic representation to arrive at the correct algebra to describe q-deformed bosons. We investigate the algebra of q-fermions and point out how different it is from the theory of q-bosons. We show that the holomorphic representation for q-fermions is indeed feasible in the framework of the theory of generalized fermions. We also examine several different q-algebras in the context of the modified Heisenberg equation of motion.
A Green Chemistry Approach to a More Efficient Asymmetric Catalyst: Solvent-Free and Highly Concentrated Alkyl Additions to Ketones

There is a great demand for development of catalyst systems that are not only efficient and highly enantioselective but are also environmentally benign. Herein we report investigations into the catalytic asymmetric addition of alkyl and functionalized alkyl groups to ketones under highly concentrated and solvent-free conditions. In comparison with standard reaction conditions employing toluene and hexanes, the solvent-free and highly concentrated conditions permit reduction in catalyst loading by a factor of 2- to 40-fold. These new conditions are general and applicable to a variety of ketones and dialkylzinc reagents to provide diverse tertiary alcohols with high enantioselectivities. Using cyclic conjugated enones, we have performed a tandem asymmetric addition/diastereoselective epoxidation using the solvent-free addition conditions followed by introduction of a 5.5 M decane solution of tert-butyl hydroperoxide (TBHP) to generate epoxy alcohols. This one-pot procedure allows access to syn epoxy alcohols with three contiguous stereocenters with excellent enantio- and diastereoselectivities and high yields. Both the solvent-free asymmetric additions and asymmetric addition/diastereoselective epoxidation reactions have been conducted on larger scale (5 g substrate) with 0.5 mol % catalyst loadings. In these procedures, enantioselectivities equal to or better than 92% were obtained with isolated yields of 90%. The solvent-free and highly concentrated conditions are a significant improvement over previous solvent-based protocols. Further, this chemistry represents a rare example of a catalytic asymmetric reaction that is highly enantioselective under more environmentally friendly solvent-free conditions.
Pharmacogenetics of the Effects of Colesevelam on Colonic Transit in Irritable Bowel Syndrome with Diarrhea

Background Protein products of klothoβ (KLB) and fibroblast growth factor receptor 4 (FGFR4) impact fibroblast growth factor 19-mediated feedback inhibition of hepatic bile acid (BA) synthesis. Variants of KLB and FGFR4 influence colonic transit (CT) in diarrhea-predominant irritable bowel syndrome (IBS-D).
Affine toric equivalence relations are effective

Any map of schemes defines an equivalence relation , the relation of ``being in the same fiber''. We have shown elsewhere that not every equivalence relation has this form, even if it is assumed to be finite. By contrast, we prove here that every toric equivalence relation on an affine toric variety does come from a morphism and that quotients by finite toric equivalence relations always exist in the affine case. In special cases, this result is a consequence of the vanishing of the first cohomology group in the Amitsur complex associated to a toric map of toric algebras. We prove more generally the exactness of the Amitsur complex for maps of commutative monoid rings.
Controlled random walk with a target site

We consider a symmetric simple random walk $\{W_i\}$ on $\mathbb{Z}^d, d=1,2$, in which the walker may choose to stand still for a limited time. The time horizon is $n$, the maximum consecutive time steps which can be spent standing still is $m_n$ and the goal is to maximize $\mathbb{P}(W_n=0)$. We show that for $d=1$, if $m_n \gg (\log n)^{2+\gamma}$ for some $\gamma>0$, there is a strategy for each $n$ yielding $\mathbb{P}(W_n = 0) \to 1$. For $d=2$, if $m_n \gg n^\epsilon$ for some $\epsilon>0$ then there are strategies yielding $\liminf_n \mathbb{P}(W_n=0)>0$.
EXECUTIVE COMPENSATION AND FIRM SIZE: AN AGENCY PERSPECTIVE

The relationship between the amount of executive compensation and the size of the firm has long been a disputed area of economics. Baumol (1959) was among the first to observe that firm size and executive compensation appear to be positively correlated. This view was further supported by the works of McGuire, Chin and Elbing (1962), Ciscel (1974), and Walkling & Long (1984). Other studies (see e.g., Lewellen and Huntsman (1970) have contended that profit maximization is the principal determinant of variations in executive compensation. More recently, a debate has raged in the popular press as to whether executives of the auto industry deserve the largest salaries recently awarded them (see e.g., Fortune 1984).
Plasma Deposition and Characterization of Thin Silicon‐Rich Silicon Nitride Films

Films of containing excess Si were prepared by plasma‐enhanced chemical vapor deposition at 350°C by the glow discharge reaction of gaseous (1.9% in helium) in in a tube‐type, hot wall reactor at 450 kHz RF frequency. The amount of silicon in the films was adjusted by varying the reactant gas‐phase ratio. The deposited films had a refractive index range of 1.90–2.70. Auger analysis (depth profiles) showed that the Si concentration in the films increased with refractive index. A small amount of oxygen contamination was observed on all film surfaces. X‐ray photoelectron spectroscopy measurements showed the presence of excess silicon, probably present as amorphous Si clusters in films with a high refractive index and oxygen contamination in all deposited film surfaces. Fourier transform infrared and nuclear reaction analysis for hydrogen showed that the hydrogen concentration ranged from 13 to 22 atomic percent and the hydrogen concentration decreased monotonically with increased refractive index. Etch rates of deposited films in glow discharge decrease monotonically with decreased hydrogen and increased silicon concentration in the films.
X-34 Experimental Aeroheating at Mach 6 and 10

Critical technologies are being developed to support the goals of the NASA Office of Aeronautics and Space Transportation Technology Access to Space initiative for next-generation reusable space transportation systems. From the perspective of aerothermodynamic performance throughout the flight trajectory, the Reusable Launch Vehicle program incorporates conceptual analysis, ground-based testing, and computational fluid dynamics to provide flyable suborbital flight demonstrator vehicles. This report provides an overview of the hypersonic aeroheating wind tunnel test program conducted at the NASA Langley Research Center in support of one of these vehicles, the X-34 small reusable technology demonstrator program. Global surface heat transfer images, surface streamline patterns, and shock shapes were measured on 0.0153- and 0.0183-scale models of proposed X-34 flight vehicles at Mach 6 and 10 in air. The primary parametrics that were investigated include angles-of-attack from 0 to 35 deg. and freestream unit Reynolds numbers from 0.5 to 8 million per foot (which was sufficient to produce laminar, transitional, and turbulent heating data), both with and without control surface deflections. Comparisons of the experimental data to computational predictions are included, along with a discussion of the implications of some of the experimental flow features for the flight vehicle.
A Fefferman-Graham-Like Expansion for Null Warped AdS(3)

We consider null warped AdS 3 solutions of three-dimensional gravity coupled to a massive vector field. We isolate a certain set of non-propagating solutions to the equations of motion, which we argue are the ones relevant for understanding the stress tensor sector of the dual field theory. We construct a map from these modes to solutions of three-dimensional Einstein gravity with a negative cosmological constant, and thus show that they admit a Fefferman-Graham-like asymptotic expansion. We also compute the renormalized on-shell action for these modes at full non-linear level and propose that the dual stress-energy tensor couples to the boundary metric of the auxiliary AdS 3 spacetime. The holographic stress tensor we obtain is symmetric, conserved and its trace yields the same conformal anomaly as in AdS 3.
A multiphase model for the intracluster medium

Constraints on the clustered mass density m of the universe derived from the observed population mean intracluster gas fraction h fICM i of X–ray clusters may be biased by reliance on a single-phase assumption for the thermodynamic structure of the intracluster medium (ICM). We propose a descriptive model for multiphase structure in which a spherically symmetric ICM contains isobaric density perturbations with a radially dependent variance σ 2 (r) = σ 2 (1 + r 2 /r 2 c ) ǫ . The model extends the work of Gunn & Thomas (1996) which assumed radially independent density fluctuations thoughout the ICM. Fixing the X–ray emission profile and emission weighted temperature, we explore two independently observable signatures of the model in the {σc, ǫ} space. For bremsstrahlung dominated emission, the central Sunyaev–Zeldovich (SZ) decrement in the multiphase case is increased over the single-phase case and multiphase X–ray spectra in the range 0.1 − 20 keV are flatter in the continuum and exhibit stronger low energy emission lines than their single-phase counterpart. We quantify these effects for a fiducial 10 8 K cluster and demonstrate how the combination of SZ and X–ray spectroscopy can be used to identify a preferred location {ˆ σc,ˆ} in the model plane. From these parameters, the correct value of h fICM i in the multiphase model results, allowing an unbiased estimate of m to be recovered. The consistency of recent determinations of the Hubble constant from SZ and X–ray observations with values determined by other methods suggests that biases in ICM gas fractions are small, ∼ 20%.
A model of environmental craze growth in polymers

A model of environmental craze growth has been developed based on the customary meniscus (or Rayleigh-Taylor) instability model of craze propagation but allowing for the possibility that environmental plasticization may cause the active layer of material adjacent to the craze to be of significant thickness with respect to the fibril spacing. Initially, as the active layer thickness increases, the fibril growth rate increases at constant fibril spacing, but eventually the fibril spacing comes to be controlled only by the active layer thickness and not by the surface tension and stress. This model of craze growth has been coupled to a model of stress-enhanced case II diffusion that is itself based on the Thomas-Windle model. Two main regimes of craze thickness growth are distinguished. In one the craze growth rate is controlled by the velocity of the diffusion front, the meniscus instability growth rate is assumed to be relatively slow, so that a significant plasticized active layer exists whose thickness assures that the meniscus instability front travels at the same speed as the diffusion front. In the other regime the propagation of the craze front is sufficiently fast that it also forms the diffusion front, so the growth rate is controlled by a combination of the two processes: diffusion and meniscus instability.
Evolutionary Implementation and Congestion Pricing

We consider an implementation problem faced by a planner who manages a roadway network. The problem entails both hidden information and hidden actions. We solve the planner’s problem by introducing a new class of mechanisms and a new notion of implementation. The mechanisms, called price schemes, attach transfers to the available routes; they do not involve direct revelation. The method of implementation is evolutionary, requiring that players who follow any reasonable myopic adjustment process eventually learn to behave as the planner desires. We show that efficient behaviour can be guaranteed using simple, decentralized price schemes.
Generic character sheaves on disconnected groups and character values

We relate a generic character sheaf on a disconnected reductive group with a character of the rational points of the group over a finite field extending a known result in the connected case.
Shock waves in a Bose-Einstein condensate

A theoretical possibility of shock wave formation in a high-density Bose-Einstein condensate with strong repulsive interaction is reported. A mechanism of transformation of sound waves into shock waves is described. The speed of shock waves as well as relationships between jumps of velocity and density at the front of the surface of discontinuity are derived. The theory is illustrated by the analytical solution for shock wave propagation in a dense condensate cloud.
Prediction of fluctuating pressure in attached and separated turbulent boundary-layer flow

A methodology is presented that predicts the fluctuating pressure and power spectra for attached zeropressure gradient and separated turbulent boundary-layer flow on smooth and rough surfaces. Attached flow conditions use a prediction technique that employs a transformation of boundary-layer properties from the compressible to the incompressible plane where a comparison can be made to an extensive data base. For a rough wall, it is shown that the rms pressure, which scales with wall shear, can be predicted by augmenting the smooth wall value by the rough/smooth skin-friction ratio. Relative to nonattached flow, represented by two-dimensional compression corner and three-dimensional fin-generated shock/boundary-layer interactions, the rms pressure is shown to scale with approach flow conditions and the oblique shock in viscid pressure rise. For this situation, a new in viscid angle has been defined as = a + /3 sin^U/M) where a is the shock generator angle and /3 is a parameter based on two-dimensional or three-dimensional interactions. Both rms pressure and power spectra have been correlated in terms of undisturbed approach flow boundary-layer parameters and modified inviscid shock strength relations to provide engineering solutions for the design resolution to complex flow problems.
Provider Responses to Patients Controlling Access to their Electronic Health Records: A Prospective Cohort Study in Primary Care

INTRODUCTION Applying Fair Information Practice principles to electronic health records (EHRs) requires allowing patient control over who views their data.
Tracking and monitoring oil slicks using remote sensing

Oil spills can harm marine life in the oceans, estuaries and wetlands. To limit the damage by a spill and facilitate cleanup efforts, emergency managers need information on spill location, size and extent, direction and speed of oil movement, and wind, current and wave information for predicting oil drift and dispersion. The main operational data requirements are fast turn-around time and frequent imaging to monitor the dynamics of the spill. Remote sensors on satellites and aircraft meet most of these requirements by tracking the spilled oil at various resolutions, over wide areas and at frequent intervals. Satellite sensors can provide key inputs to drift prediction models, such as oil spill location and extent, currents, winds and wave conditions over large offshore and ocean areas. Airborne remote sensing techniques provide the fast turn-around time and frequent imaging for monitoring the dynamics of the spill and for targeting of skimming and booming efforts. Remotely controlled underwater robots and new acoustic waveguide techniques can be deployed to track submerged oil plumes.