cssi/SciSciGPT-SciSciNet huggingface dataset:
2-(hydroxyalkyl)estradiols: Synthesis and biological evaluation

Synthetic estrogens possessing hydroxyalkyl side chains at the C-2 position of the A-ring were designed in order to further elucidate the structural and electronic requirements of the estrogen receptor to A-ring modifications. Furthermore, these compounds were envisaged as being stable analogs of the estradiol metabolite 2-hydroxyestradiol. The homologous series of 2-(hydroxyalkyl)estradiols 1−3 has been prepared by chain extension of 2-formylestradiol 6, which, in turn, was prepared via ortholithiation of estradiol. The substituted estradiols 1−3 were assayed for their abilities to bind to the estrogen receptor in MCF-7 cells and induce estrogen-responsive gene expression. The estradiol homologs exhibited significantly weaker affinity than estradiol for the MCF-7 cell estrogen receptor, with relative binding affinities (estradiol = 100) ranging from 1.11 for 2-(hydroxymethyl)estradiol (1) to 0.073 for 2-(hydroxypropyl)estradiol (3). The relative activities for mRNA induction of the pS2 gene by the estrad...
On degree growth and stabilization of three-dimensional monomial maps

Given a rational self-map f : X X on an n-dimensional Kahler manifold X, one can define a pullback map f ∗ : H(X) → H(X) for 0 ≤ p ≤ n. In general, the pullback does not commute with iteration; that is, (f ∗)k = (f k)∗. Following Sibony ([Si]; see also [FoSi]), we call the map f (algebraically) stable if the action on the cohomology of X is compatible with iterations. More precisely, f is called p-stable if the pullback on H(X) satisfies (f ∗)k = (f k)∗ for all k ∈N. If f is not p-stable on X, one might try to find a birational change of coordinate h : X ′ X such that f = h−1 f h is p-stable. This is not always possible even for p = 1, as shown by Favre [Fa]. However, for p = 1 and n = 2, one can find such a stable model (with at worst quotient singularities) for quite a few classes of surface maps [DFa; FaJ]. Also for p = 1, such a model can be obtained for certain monomial maps [Fa; JW; L]. For an n × n integer matrix A = (ai,j ), the associated monomial map fA : (C∗)n → (C∗)n is defined by fA(x1, . . . , xn) = (∏
Hypervelocity Stars: From the Galactic Center to the Halo

Hypervelocity stars (HVSs) traverse the Galaxy from the central black hole to the outer halo. We show that the Galactic potential within 200 pc acts as a high-pass filter preventing low-velocity HVSs from reaching the halo. To trace the orbits of HVSs throughout the Galaxy, we construct two forms of the potential which reasonably represent the observations in the range 5-105 pc: a simple spherically symmetric model and a bulge-disk-halo model. We use the Hills mechanism (disruption of binaries by the tidal field of the central black hole) to inject HVSs into the Galaxy and to compute the observable spatial and velocity distributions of HVSs with masses in the range 0.6-4 M☉. These distributions reflect the mass function in the Galactic center, properties of binaries in the Galactic center, and aspects of stellar evolution and the injection mechanism. For 0.6-4 M☉ main-sequence stars, the fraction of unbound HVSs and the asymmetry of the velocity distribution for their bound counterparts increase with stellar mass. The density profiles for unbound HVSs decline with distance from the Galactic center approximately as -->r−2 (but are steeper for the most massive stars, which evolve off the main sequence during their travel time from the Galactic center); the density profiles for the bound ejecta decline with distance approximately as -->r−3. In a survey with a limiting magnitude of -->V 23, the detectability of HVSs (unbound or bound) increases with stellar mass.
Generation of nonequilibrium optical phonons in GaAs/AlAs quantum wells by intrasubband and intersubband scatterings

The generation of a nonequilibrium population of optical phonons by photoexcited hot electrons in semiconductor quantum wells is investigated theoretically. The microscopic model of electron-phonon interaction proposed by Huang and Zhu has been used to compute the distributions of confined longitudinal optical phonons and interface modes in GaAs/AlAs quantum wells as a function of well width. Experimental tests of the calculated distributions by Raman scattering are discussed.
A Theory of Wage Dynamics

A dynamic, equilibrium model of long term (implicit) labour contracts under incomplete but symmetric information is developed. Workers are assumed to be risk averse and of unknown ability or productivity. Risk neutral firms learn, as do workers, about each worker's productivity by observing the worker's output over time. It is shown that equilibrium contracts provide for wages which never decline with age and increase only when the worker's market value increases above his current wage. In addition to characterizing the equilibrium wage contract, we also derive some of its implications for the behaviour of aggregate wages across various groups of workers. These implications explain some findings in the recent empirical literature on ageearnings profiles. In particular our model can explain why earnings may be positively related to experience even after controlling for productivity, as some empirical studies have indicated.
Facioscapulohumeral Muscular Dystrophy

Facioscapulohumeral muscular dystrophy (FSHD) is a common type of adult muscular dystrophy and is divided into types 1 and 2 based on genetic mutation. Clinically, both FSHD types often show asymmetric and progressive muscle weakness affecting initially the face, shoulder, and arms followed by the distal then proximal lower extremities. Approximately 95% of patients, termed FSHD1, have a deletion of a key number of repetitive elements on chromosome 4q35. The remaining 5%, termed FSHD2, have no deletion on chromosome 4q35. Nevertheless, both types share a common downstream mechanism, making it possible for future disease-directed therapies to be effective for both FSHD types.
Noncritical M-theory in 2+1 dimensions as a nonrelativistic Fermi liquid

We claim that the dynamics of noncritical string theories in two dimensions is related to an underlying noncritical version of M-theory, which we define in terms of a double-scaled nonrelativistic Fermi liquid in 2+1 dimensions. After reproducing Type 0A and 0B string theories as solutions, we study the natural M-theory vacuum. The vacuum energy of this solution can be evaluated exactly, its form suggesting a duality to the Debye model of phonons in a melting solid, and a possible topological nature of the theory. The physical spacetime is emergent in this theory, only for states that admit a hydrodynamic description. Among the solutions of the hydrodynamic equations of motion for the Fermi surface, we find families describing the decay of one two-dimensional string theory into another via an intermediate M-theory phase.
Academic outcomes among principal investigators, co-principal investigators, and non-PI researchers

Faculty at research universities are evaluated on a number of productivity measures including their ability to conduct research, teach, and engage in service. Research outcomes include publishing research results and acquiring grants and contracts to conduct additional research. While it is assumed that researchers who are awarded grants are more likely to publish research results, there is little research investigating the ways in which grants affect outcomes or how principal investigators differ from researchers who do not hold research grants or those who are co-principal investigators. This research seeks to understand if principal investigators are more or less productive than co-principal investigators and those who do not have grants, and if so, what explains that variation in productivity. It also examines whether women PIs are more or less productive than men PIs. This research uses longitudinal data drawn from an NSF funded survey of academic scientists in Carnegie-designated Research I universities in six fields: biology, chemistry, computer science, earth and atmospheric sciences, electrical engineering, and physics. From this national random sample of men and women scientists and engineers we investigate whether there is variation in the production of outcomes (e.g. publications, teaching, and training graduate students) among PIs, co-PIs, and other researchers. Findings show that productivity and outcomes vary significantly for PIs, co-PIs and by sex.
Approximate Methods for State-Space Models

State-space models provide an important body of techniques for analyzing time series, but their use requires estimating unobserved states. The optimal estimate of the state is its conditional expectation given the observation histories, and computing this expectation is hard when there are nonlinearities. Existing filtering methods, including sequential Monte Carlo, tend to be either inaccurate or slow. In this paper, we study a nonlinear filter for nonlinear/non-Gaussian state-space models, which uses Laplace’s method, an asymptotic series expansion, to approximate the state’s conditional mean and variance, together with a Gaussian conditional distribution. This Laplace Gaussian filter (LGF) gives fast, recursive, deterministic state estimates, with an error which is set by the stochastic characteristics of the model and is, we show, stable over time. We illustrate the estimation ability of the LGF by applying it to the problem of neural decoding and compare it to sequential Monte Carlo both in simulatio...
Simplicial radditive functors

The simplicial extension of any functor from Setsto Setswhich commutes with directed colimits respects weak equivalences. In the present paper we construct a framework which allows one to extend this result to a wide class of model categories and functors between such categories.
Generation and Cyclization of Acyl Radicals from Thiol Esters Under Nonreducing, Tin-Free Conditions

The preparation of 2-(2-((tert-butyloxycarbonyl)amino)phenyl)ethyl mercaptan from 2-(2-aminophenyl)ethanol is described. This thiol is condensed with a series of suitably unsaturated carboxylic acids to give a series of thiol esters. The Boc group is removed and the amine reacted with isoamyl nitrite to give a series of diazonium salts. Exposure to iodide in acetone solution then generates the aryl radical, which undergoes intramolecular homolytic substitution at sulfur with liberation of the acyl radical. Following acyl radical cyclization, quenching by iodine and then elimination of HI leads to the isolation of α-methylene cycloalkanones in good yield.
Convex Relaxation of Optimal Power Flow—Part I: Formulations and Equivalence

This tutorial summarizes recent advances in the convex relaxation of the optimal power flow (OPF) problem, focusing on structural properties rather than algorithms. Part I presents two power flow models, formulates OPF and their relaxations in each model, and proves equivalence relationships among them. Part II presents sufficient conditions under which the convex relaxations are exact.
Palladium-Catalyzed Indole, Pyrrole, and Furan Arylation by Aryl Chlorides

The palladium-catalyzed direct arylation of indoles, pyrroles, and furans by aryl chlorides has been demonstrated. The method employs a palladium acetate catalyst, 2-(dicyclohexylphosphino)-biphenyl ligand, and an inorganic base. Electron-rich and electron-poor aryl chlorides as well as chloropyridine coupling partners can be used, and arylated heterocycles are obtained in moderate to good yields. Optimization of base, ligand, and solvent is required for achieving best results.
RANDOM SEEKING: A GENERAL, EFFICIENT, AND INFORMED RANDOMIZED SCHEME FOR DYNAMIC LOAD BALANCING

We propose a completely general, informed randomized dynamic load balancing method called random seeking (RS) suitable for parallel algorithms with characteristics found in many search algorithms used in artificial intelligence and operations research and many divide-and-conquer algorithms. In it, source processors randomly seek out sink processors for load balancing by flinging "probe" messages. These probes not only locate sinks, but also collect load distribution information which is used to efficiently regulate load balancing activities. We empirically compare RS with a well-known randomized dynamic load balancing method, the random communication (RC) strategy, by using them in parallel best-first branch-and-bound algorithms on up to 512 processors of a parallel system. We find that the RC execution times are more than those of RS by 16–67% when used to perform combined dynamic quantitative and qualitative load balancing, and by 9–74% when used to perform only dynamic quantitative load balancing.
Subsidized monopolists and product prices: the case of Major League Baseball

I analyse the setting of ticket prices when teams receive subsidization. I model teams as entertainment providers, where entertainment is generated by selling wins and amenities. I argue that subsidization of teams generally comes from subsidizing the amenities in the teams’ stadiums. Subsidization lowers the marginal cost of providing them to fans, driving ticket prices lower. The empirical analysis suggests that this is the case. The average team playing in a 5-year-old public stadium charges a ticket price that is 40 cents less than the same team playing in a private stadium of the same age.
Planetesimal Disk Evolution Driven by Embryo-Planetesimal Gravitational Scattering

The process of gravitational scattering of planetesimals by a massive protoplanetary embryo is explored theoretically. We propose a method to describe the evolution of the disk surface density, eccentricity, and inclination caused by the embryo-planetesimal interaction. It relies on an analytical treatment of the scattering in two extreme regimes of the planetesimal epicyclic velocities: shear dominated (dynamically "cold") and dispersion dominated (dynamically "hot"). In the former, planetesimal scattering can be treated as a deterministic process. In the latter, scattering is mostly weak because of the large relative velocities of interacting bodies. This allows one to use the Fokker-Planck approximation and the two-body approximation to explore the disk's evolution. We compare the results obtained by this method with the outcomes of direct numerical integrations of planetesimal orbits, and they agree quite well. In the intermediate-velocity regime, an approximate treatment of the disk evolution is proposed based on interpolation between the two extreme regimes. We also calculate the rate of the embryo's mass growth in an inhomogeneous planetesimal disk and demonstrate that it is in agreement with both the simulations and earlier calculations. Finally, we discuss the question of the direction of the embryo-planetesimal interaction in the dispersion-dominated regime and demonstrate that it is repulsive. This means that the embryo always forms a gap in the disk around it. The machinery developed here will be applied to realistic protoplanetary systems in future papers.
An Improved Circuit for Implementing the Six-Port Technique of Microwave Measurements

In a companion paper, circuit design criteria were developed which lead to optimal performance in applying the six-port technique to the measurement of microwave parameters. A circuit which approximately satisfies these new design goals is described. Together with its several variants, it promises to become, in many applications, the "preferred" six-port circuit.
Complexity-regularized image denoising

We study a new approach to image denoising based on complexity regularization. This technique presents a flexible alternative to the more conventional l/sup 2/,l/sup 1/, and Besov regularization methods. Different complexity measures are considered, in particular those induced by state-of-the-art image coders. We focus on a Gaussian denoising problem and derive a connection between complexity-regularized denoising and operational rate-distortion optimization. This connection suggests the use of efficient algorithms for computing complexity-regularized estimates. Bounds on denoising performance are derived in terms of an index of resolvability that characterizes the compressibility of the true image. Comparisons with state-of-the-art denoising algorithms are given.
Dielectrometry measurements of moisture dynamics in oil-impregnated pressboard

In oil-impregnated pressboard of medium and low humidity the complex dielectric spectrum's shape and amplitude do not change with variations in temperature and moisture content, but only shift in frequency. Thus it is possible to create a 'universal' curve, with appropriate temperature correction factors, which can be used to extract information about the moisture dynamics of solid transformer insulation from dielectrometry measurements. To create the universal curve, measurements are taken with the material placed in a parallel-plate structure whose complex impedance is measured. To measure spatial distributions of dielectric properties, imposed /spl omega/-k (frequency-wavenumber) dielectrometry is used, where a set of interdigitated electrodes on one surface of the material cause the electric field to have a limited depth of penetration into the dielectric, proportional to the electrode spacing. Measurements using the parallel-plate methodology establish a mapping of the dielectric spectrum of EHV-Weidmann HIVAL pressboard impregnated with Shell Diala A transformer oil, as a function of temperature and water content. This mapping is then used to determine spatial moisture profiles in pressboard in other experiments which make use of a three-wavelength interdigitated sensor. >
Robustness of nonlinear predictor feedback laws to time- and state-dependent delay perturbations

Much recent progress has been achieved for stabilization of linear and nonlinear systems with input delays that are long and dependent on either time or the plant state-provided the dependence is known. In this paper we consider the delay variations as unknown and study robustness of nominal constant-delay predictor feedbacks under delay variations that depend on time and the state. We show that when the delay perturbation and its rate have sufficiently small magnitude, the local asymptotic stability of the closed-loop system, under the nominal predictor-based design, is preserved. For the special case of linear systems, and under only time-varying delay perturbations, we prove robustness of global exponential stability of the predictor feedback when the delay perturbation and its rate are small in any one of four different metrics. We present two examples, one that is concerned with the control of a DC motor through a network and one of a teleoperation-like system.
Trimeric perfluoro-ortho-phenylenemercury: a versatile Lewis acidic host.

Trimeric perfluoro-ortho-phenylenemercury (1) constitutes one of the simplest trifunctional Lewis acidic hosts. In addition to cooperative effects arising from the proximity of the mercury(11) centers, the electron-withdrawing properties of the backbone and the accessibility of the electrophilic sites lead to the facile complexation of neutral and electron rich substrates. The planarity of the structure as well as its overall polarizability compounded with relativistic effects at mercury also permits the occurrence of non-covalent interactions and accounts for the tendency of this compound to form cofacial dimers. Collectively, the Lewis acidic properties of 1 as well as its ability to engage in non-covalent interactions can be held responsible for its ability to form extended binary supramolecular stacks with arenes. The photoluminescence observed in some of these supramolecular complexes corresponds to the phosphorescence of the aromatic substrate and indicate the occurrence of a mercury heavy atom effect.
Congenital quadricuspid aortic valve with displacement of the left coronary orifice

Abstract A case of a 35 year old woman with quadricuspid aortic valve and displacement of the left coronary orifice is presented. The aortic regurgitation caused by maladaptation of the supernumerary cusps was corrected surgically.
From Breaking Bad to Worse: Exploiting Homologous DNA Repair Deficiency in Cancer

DNA repair deficiencies are common among cancer cells and represent a potential vulnerability that might be exploited by targeting compensatory repair pathways. However, the identification of synthetically lethal combinations of DNA repair defects, although of significant clinical relevance, has been somewhat anecdotal. Although numerous models have been proposed to explain synthetic lethality among DNA repair mutations, we have only a limited understanding of why a given mutation should render cells sensitive to another. In this issue of Cancer Discovery, Dietlein and colleagues define a general connection between mutations in genes involved in homologous recombination and sensitivity to inhibitors of non-homologous end joining. In doing so, they provide a mechanism to demarcate a set of seemingly diverse tumors that may be highly responsive to established DNA repair-targeted therapeutics.
Teaching the English Language Arts With Technology: A Critical Approach and Pedagogical Framework

In order to cultivate the kind of techno logy literacy in our students called for by leaders in the field, it must simultaneously be cultivated in our teachers. While the literature in the field of English education demonstrates the efficacy of computer technology in writing instruction and addresses its impact on the evolving definition of literacy in the 21st century, it does not provide measured directions for how English teachers might develop technology literacy themselves or specific plans for how they might begin to critically assess the potential that technology might hold for them in enhancing instruction. This article presents a pedagogical framework encompassing the necessary critical mindset in which teachers of the English language arts can begin to conceive their own "best practices" with technology —a framework that is based upon their needs, goals, students, and classrooms, rather than the external pressure to fit random and often decontexualized technology applications into an already complex and full curriculum. To maximize technolo gy's benefits, educators must develop a heightened, critical view of technology to determine its potential for the classroom. The steps for doing this include:
Prospects for Beyond the Standard Model Physics at the Start of the LHC13 era

The discovery of the Higgs boson along with the vigorous confirmation of the SM coupled with non-appearance of new (SUSY) particles has led to an apparent naturalness crisis. We argue the crisis stems from overestimates of finetuning. A proper evaluation of naturalness in SUSY leads to light higgsinos with mass μ ∼ 100−300 GeV while other sparticles may inhabit the multi-TeV range at little cost to naturalness. Special signatures like dilepton mass edges in gluino pair events and same-sign dibosons from wino pairs might occur at LHC13. An ILC with √ s > 2μ would make the definitive test of naturalness in the MSSM. Naturalness in the QCD sector requires the axion leading to mixed axion-WIMP dark matter. There appears a deep connection between electroweak naturalness and a DFSZ-like SUSY axion sector which gives rise to the μ ∼ f 2 a /MP parameter. Ultimately we expect detection of a higgsino-like WIMP at ton-scale DM detectors and detection of a DFSZ-type axion at ADMX.
Level Shifts and the Illusion of Long Memory in Economic Time Series

When applied to time series processes containing occasional level shifts, the log-periodogram (GPH) estimator often erroneously finds long memory. For a stationary short-memory process with a slowly varying level, I show that the GPH estimator is substantially biased, and derive an approximation to this bias. The asymptotic bias lies on the (0, 1) interval, and its exact value depends on the ratio of the expected number of level shifts to a user-defined bandwidth parameter. Using this result, I formulate the modified GPH estimator, which has a markedly lower bias. I illustrate this new estimator via applications to soybean prices and stock market volatility.
Haploinsufficiency and reduced expression of genes localized to the 8p chromosomal region in human prostate tumors

Cytogenetic and molecular studies have suggested that deletion or rearrangement of sequences that map to the short arm of chromosome 8 may be permissive for tumorigenesis in several organ systems, and in human prostate tumors in particular. In this study, we hypothesized that genes deleted for one copy and localized to the 8p chromosomal region may be transcriptionally down-regulated or ablated in affected human prostate tumor tissues. To test this hypothesis, we used cDNA microarray analysis to determine the transcriptional profiles for 259 transcribed sequences mapping to the 8p chromosomal region for seven human prostate tumor xenografts, completely characterized for numerical and structural alterations on chromosome 8, and five normal human prostate tissues. These experiments identified 33 genes differentially expressed between normal and malignant prostate tissues, the majority of which (28/33, 85%) were transcriptionally down-regulated in malignant compared to normal human prostate tissues. These findings, that haploinsufficiency and transcriptional down-regulation for genes mapping to 8p are largely coincident in human prostate tumors, should provide a powerful tool for the identification of tumor-suppressor genes associated with human prostate cancer initiation and progression.
Bounds on Volume Increase Under Dehn Drilling Operations

In this paper we investigate how the volume of a hyperbolic manifold increases under the process of removing a curve, that is, Dehn drilling. If the curve we remove is a geodesic, we show that for a certain family of manifolds the volume increase is bounded above by is the length of the geodesic drilled. We further construct examples to show that there is no lower bound to the volume increase in terms of a monotonic unbounded function of length. In particular, this shows that volume increase is not bounded below linearly in length.1991 Mathematics Subject Classification: primary 51M10, 51M20; secondary 51M25, 52C25.
Electoral business cycles in OECD countries

Studies of Organisation for Economic Co-operation and Development (OECD) countries have generally failed to detect real economic expansions in preelection periods, casting doubt on the existence of opportunistic political business cycles. We develop a theory that predicts that a substantial portion of the economy experiences a real decline in the preelection period if the election is associated with sufficient policy uncertainty. In particular, policy uncertainty induces private actors to postpone investments with high costs of reversal. The resulting declines, which are called reverse electoral business cycles, require sufficient levels of polarization between major parties and electoral competitiveness. To test these predictions, we examine quarterly data on private fixed investment in ten OECD countries between 1975 and 2006. The results show that reverse electoral business cycles exist and as expected, depend on electoral competitiveness and partisan polarization. Moreover, simply by removing private fixed investment from gross domestic product, we uncover evidence of opportunistic cycles.
A Fourier restriction theorem based on convolution powers

We prove a Fourier restriction estimate under the assumption that certain convolution power of the measure admits an $r$-integrable density.
Applications of wavelet subband decomposition in adaptive arrays

Pre-processing radar signals incident on an adaptive array by applying an invertible transformation such as wavelets is the focus of this study. The effect of wavelet subband decomposition of radar signals prior to adaptation using an LMS algorithm or an Applebaum processor on the adaptation rate of these processors is examined. Faster adaptation rates can be achieved by inserting a wavelet transformer between the incoming signal and the LMS or Applebaum array processors. The transformation improves the condition number of the covariance matrix and thus improves the convergence rate of an array. >
The perimetric boycott: a tool for tobacco control advocacy

Objectives: To propose criteria to help advocates: (1) determine when tobacco related boycotts may be useful; (2) select appropriate targets; and (3) predict and measure boycott success. Methods: Analysis of tobacco focused boycotts retrieved from internal tobacco industry documents websites and other scholarship on boycotts. Results: Tobacco related boycotts may be characterised by boycott target and reason undertaken. Most boycotts targeted the industry itself and were called for political or economic reasons unrelated to tobacco disease, often resulting in settlements that gave the industry marketing and public relations advantages. Even a lengthy health focused boycott of tobacco industry food subsidiaries accomplished little, making demands the industry was unlikely to meet. In contrast, a perimetric boycott (targeting institutions at the perimeter of the core target) of an organisation that was taking tobacco money mobilised its constituency and convinced the organisation to end the practice. Conclusions: Direct boycotts of the industry have rarely advanced tobacco control. Perimetric boycotts of industry allies offer advocates a promising tool for further marginalising the industry. Successful boycotts include a focus on the public health consequences of tobacco use; an accessible point of pressure; a mutual interest between the target and the boycotters; realistic goals; and clear and measurable demands.
Early-type galaxy distances from the Fundamental Plane and surface brightness fluctuations

We compare two of the most popular methods for deriving distances to early-type galaxies: the Fundamental Plane (FP) and surface brightness fluctuations (SBF). Distances for 170 galaxies are compared. A third set of distances is provided by predictions derived from the density field of the IRAS redshift survey. Overall there is good agreement between the different distance indicators. We investigate systematic trends in the residuals of the three sets of distance comparisons. First, we find that several nearby, low-luminosity, mainly SO galaxies have systematically low FP distances. Because these galaxies also have Mg 2 indices among the lowest in the sample, we conclude that they deviate from the FP partly because of recent star formation and consequently low mass-to-light ratios; differences in their internal velocity structures may also play a role. Secondly, we find some evidence that the ground-based I-band SBF survey distances (Tonry et al. 2001) begin to show a bias near the survey limit at cz > 3500 km s - 1 , which is expected for this sort of distance-limited survey, but had not previously been demonstrated. Although SBF and FP distances are affected in opposite senses by errors in the Galactic extinction estimates, we find no evidence for biases in the distances due to Galactic extinction. The tie between the Cepheid-calibrated SBF distances (Mpc) and the farfield calibrated FP distances (km s - 1 ) yields a Hubble constant H 0 = 68 ′ 3 km s - 1 Mpc - 1 , while the comparison between SBF and the IRAS-reconstructed distances yields H 0 = 74 ′ 2 km s - 1 Mpc - 1 (independent errors only). Thus there is a marginal inconsistency in the direct and IRAS-reconstructed ties to the Hubble flow (this can be seen independently of the SBF distances). Possible explanations include systematic errors in the redshift survey completeness estimates or in the FP aperture corrections, but at this point the best estimate of H 0 may come from a simple average of the above two estimates. After revising the SBF distances downward by 2.8 per cent to be in agreement with the final set of Key Project Cepheid distances (Freedman et al.), we conclude that H 0 = 73 ′ 4 ′ 11 km s - 1 Mpc - 1 from early-type galaxies, where the second error bar represents the total systematic uncertainty in the distance zero-point. We also discuss the 'fluctuation star count' N ≡ m - m t o t , recently introduced by Tonry et al. (2001) as a less demanding alternative to (V - I) for calibrating SBF distances. The N-calibrated SBF method is akin to a hybrid SBF-FP distance indicator, and we find that the use of N actually improves the SBF distances. Further study of the behaviour of this quantity may provide an important new test for models of elliptical galaxy formation.
Ioana's Superrigidity Theorem and Orbit Equivalence Relations

We give a survey of Adrian Ioana's cocycle superrigidity theorem for profinite actions of Property (T) groups and its applications to ergodic theory and set theory in this expository paper. In addition to a statement and proof of Ioana's theorem, this paper features the following: (i) an introduction to rigidity, including a crash course in Borel cocycles and a summary of some of the best-known superrigidity theorems; (ii) some easy applications of superrigidity, both to ergodic theory (orbit equivalence) and set theory (Borel reducibility); and (iii) a streamlined proof of Simon Thomas's theorem that the classification of torsion-free abelian groups of finite rank is intractable.
Computational Cosmology: From the Early Universe to the Large Scale Structure

In order to account for the observable Universe, any comprehensive theory or model of cosmology must draw from many disciplines of physics, including gauge theories of strong and weak interactions, the hydrodynamics and microphysics of baryonic matter, electromagnetic fields, and spacetime curvature, for example. Although it is difficult to incorporate all these physical elements into a single complete model of our Universe, advances in computing methods and technologies have contributed significantly towards our understanding of cosmological models, the Universe, and astrophysical processes within them. A sample of numerical calculations (and numerical methods applied to specific issues in cosmology are reviewed in this article: from the Big Bang singularity dynamics to the fundamental interactions of gravitational waves; from the quark-hadron phase transition to the large scale structure of the Universe. The emphasis, although not exclusively, is on those calculations designed to test different models of cosmology against the observed Universe.
Energy landscapes and solved protein-folding problems

Energy-landscape theory has led to much progress in protein folding kinetics, protein structure prediction and protein design. Funnel landscapes describe protein folding and binding and explain how protein topology determines kinetics. Landscapeoptimized energy functions based on bioinformatic input have been used to correctly predict low-resolution protein structures and also to design novel proteins automatically.
Belief propagation for continuous state spaces: stochastic message-passing with quantitative guarantees

The sum-product or belief propagation (BP) algorithm is a widely used message-passing technique for computing approximate marginals in graphical models. We introduce a new technique, called stochastic orthogonal series message-passing (SOSMP), for computing the BP fixed point in models with continuous random variables. It is based on a deterministic approximation of the messages via orthogonal series basis expansion, and a stochastic estimation of the basis coefficients via Monte Carlo techniques and damped updates. We prove that the SOSMP iterates converge to a δ-neighborhood of the unique BP fixed point for any tree-structured graph, and for any graphs with cycles in which the BP updates satisfy a contractivity condition. In addition, we demonstrate how to choose the number of basis coefficients as a function of the desired approximation accuracy δ and smoothness of the compatibility functions. We illustrate our theory with both simulated examples and in application to optical flow estimation.
Nosocomial transmission of multidrug-resistant mycobacterium tuberculosis

Before 1989, reports of nosocomial transmission of Mycobacterium tuberculosis were infrequent. Most reports involved a small number of patients or health care workers (HeWs) and were traced to patients with unrecognized infectious tuberculosis. Beginning in approximately 1985, the incidence of tuberculosis in the United States reversed its downward trend and began to increase. 1'2 From 1989 through 1992, the Hospital Infections Program, in conjunction with other Centers for Disease Control and Prevention (CDC) components, state and local health officials, and hospital personnel, investigated eight outbreaks of nosocomial tuberculosis. 38 Most of these outbreaks involved multidrug-resistant strains of M. tuberculosis (MDR-TB) and patients with HIV infection. In this article, we review the epidemiology of these MDR-TB outbreaks and describe the efficiency of control measures implemented at three of the hospitals with MDR-TB outbreaks.
Wavelets and recursive filter banks

It is shown that infinite impulse response (IIR) filters lead to more general wavelets of infinite support than finite impulse response (FIR) filters. A complete constructive method that yields all orthogonal two channel filter banks, where the filters have rational transfer functions, is given, and it is shown how these can be used to generate orthonormal wavelet bases. A family of orthonormal wavelets that have a maximum number of disappearing moments is shown to be generated by the halfband Butterworth filters. When there is an odd number of zeros at pi it is shown that closed forms for the filters are available without need for factorization. A still larger class of orthonormal wavelet bases having the same moment properties and containing the Daubechies and Butterworth filters as the limiting cases is presented. It is shown that it is possible to have both linear phase and orthogonality in the infinite impulse response case, and a constructive method is given. It is also shown how compactly supported bases may be orthogonalized, and bases for the spline function spaces are constructed. >
Achievability results for statistical learning under communication constraints

The problem of statistical learning is to construct an accurate predictor of a random variable as a function of a correlated random variable on the basis of an i.i.d. training sample from their joint distribution. Allowable predictors are constrained to lie in some specified class, and the goal is to approach asymptotically the performance of the best predictor in the class. We consider two settings in which the learning agent only has access to rate-limited descriptions of the training data, and present information-theoretic bounds on the predictor performance achievable in the presence of these communication constraints. Our proofs do not assume any separation structure between compression and learning and rely on a new class of operational criteria specifically tailored to joint design of encoders and learning algorithms in rate-constrained settings.
Diastereoselective diels-alder reactions between substituted 1,3-butadienes and n-α-methylbenzylmaleimide

Abstract The TiCl 4 catalyzed reaction between 2- t -butyl-1,3-butadiene and N-α-methylbenzylmaleimide at −65°C affords diastereomeric Diels-Alder adducts in a 15:1 ratio. The structure of the major adduct was determined by x-ray.
Evidence for Edge-State Photoluminescence in Graphene Quantum Dots

For a practical realization of graphene-based logic devices, the opening of a band gap in graphene is crucial and has proven challenging. To this end, several synthesis techniques, including unzipping of carbon nanotubes, chemical vapor deposition, and other bottom-up fabrication techniques have been pursued for the bulk production of graphene nanoribbons (GNRs) and graphene quantum dots (GQDs). However, only limited progress has been made towards a fundamental understanding of the origin of strong photoluminescence (PL) in GQDs. Here, it is experimentally shown that the PL is independent of the functionalization scheme of the GQDs. Following a series of annealing experiments designed to passivate the free edges, the PL in GQDs originates from edge-states, and an edge-passivation subsequent to synthesis quenches the PL. The results of PL studies of GNRs and carbon nano-onions are shown to be consistent with PL being generated at the edge sites of GQDs.
The Term Structures of Equity and Interest Rates

This paper proposes a dynamic risk-based model capable of jointly explaining the term structure of interest rates, returns on the aggregate market, and the risk and return characteristics of value and growth stocks. Both the term structure of interest rates and returns on value and growth stocks convey information about how the representative investor values cash flows of different maturities. We model how the representative investor perceives risks of these cash flows by specifying a parsimonious stochastic discount factor for the economy. Shocks to dividend growth, the real interest rate, and expected inflation are priced, but shocks to the price of risk are not. Given reasonable assumptions for dividends and inflation, we show that the model can simultaneously account for the behavior of aggregate stock returns, an upward-sloping yield curve, the failure of the expectations hypothesis, and the poor performance of the capital asset pricing model.
Can Foreign Aid Buy Growth

The widely publicized finding that "aid promotes growth in a good policy environment" is not robust to the inclusion of new data or alternative definitions of "aid," "policy" or "growth." The idea that "aid buys growth" is on shaky ground theoretically and empirically. It doesn't help that aid agencies face poor incentives to deliver results and underinvest in enforcing aid conditions and performing scientific evaluations. Aid should set more modest goals, like helping some of the people some of the time, rather than trying to be the catalyst for society-wide transformation.
Efficient Distributed Linear Classification Algorithms via the Alternating Direction Method of Multipliers

Linear classification has demonstrated success in many areas of applications. Modern algorithms for linear classification can train reasonably good models while going through the data in only tens of rounds. However, large data often does not fit in the memory of a single machine, which makes the bottleneck in large-scale learning the disk I/O, not the CPU. Following this observation, Yu et al. (2010) made significant progress in reducing disk usage, and their algorithms now outperform LIBLINEAR. In this paper, rather than optimizing algorithms on a single machine, we propose and implement distributed algorithms that achieve parallel disk loading and access the disk only once. Our large-scale learning algorithms are based on the framework of alternating direction methods of multipliers. The framework derives a subproblem that remains to be solved eciently for which we propose using dual coordinate descent and trust region Newton method. Our experimental evaluations on large datasets demonstrate that the proposed algorithms achieve significant speedup over the classifier proposed by Yu et al. running on a single machine. Our algorithms are faster than existing distributed solvers, such as Zinkevich et al. (2010)’s parallel stochastic gradient descent and Vowpal Wabbit.
Eliminating stale data references through array data-flow analysis

We develop a compiler algorithm for detecting references to stale data in shared-memory multiprocessors. The algorithm consists of two key analysis techniques, stale reference detection and locality preserving analysis. While the stale reference detection finds the memory reference patterns that may violate cache coherence, the locality preserving analysis minimizes the number of such stale references by analyzing both temporal and spatial reuses. By computing the regions referenced by arrays inside loops, we extend the previous scalar algorithms for more precise analysis. We have implemented the algorithm on the Polaris parallelizing compiler, and using execution-driven simulations on Perfect Club benchmarks we demonstrate how unnecessary cache misses can be eliminated by the automatic stale reference detection.
Operation of a Test Bed Axial-Gap Brushless Dc Rotor with a Superconducting Stator

A variable-speed axial-gap motor with a stator consisting of four liquid helium cooled superconducting electromagnets (two pole pairs) was built1 and proof tested up to 608 rpm in November 19902 as a tool for joint industry-laboratory evaluation of coils fabricated from high-temperature oxide superconductors. A second rotor was fabricated with improved material, winding configuration, and wire type, and the drive system was modified to eliminate current spiking. The modified motor was characterized to design speed, 188 rad/s (1800 rpm), to acquire a performance baseline for future comparison with that of high-temperature superconducting (HTS) wire. As it becomes commercially available, HTS wire will replace the low-temperature electromagnet wire in a stator modified to control wire temperatures between 4 K and 77 K.
A learning model for the selection of problem solving strategies in continuous physical systems

The authors present a learning model for automatic selection of problem-solving strategies in a physical system working in a continuous, dynamic environment. The model is intended to provide (1) a means to classify under what circumstances one problem-solving strategy (goal-directed or data-driven) is better than another; and (2) a simple online learning mechanism for obtaining a better classification when the strategy chosen based on the initial one does not yield the desired performance. The ideas and applicability of the model are illustrated by an example system for robotic assembly which has been under implementation. >
An economic model of Brazil's ethanol-sugar markets and impacts of fuel policies

The lack of growth in the Brazilian sugarcane-ethanol complex since the 2008 financial crisis has been blamed on policies: lower mandate, holding gasoline prices below world levels, high fuel taxes, and inadequate fuel tax exemptions for ethanol. This paper develops an empirical model of the Brazilian fuel-ethanol-sugar complex to analyze the impacts of these policies. Unlike biofuel mandates and tax exemptions elsewhere, Brazil's fuel-ethanol-sugar markets and fuel policies are unique such that each policy, in theory, has an ambiguous impact on the market price of ethanol and hence on sugarcane and sugar prices. The results indicate two policies that seemingly help the ethanol industry do otherwise in reality: low gasoline taxes and high anhydrous tax exemptions lower ethanol prices. But higher mandates, hydrous ethanol tax exemptions, and gasoline prices had the expected impact of increasing ethanol and sugar prices. Eliminating Brazilian ethanol tax exemptions and mandates reduces ethanol prices by 21 percent. Observed changes in prices are explained by outward shifts in fuel transportation and sugar export demand curves, and bad weather reducing sugarcane supply.