cssi/SciSciGPT-SciSciNet huggingface dataset:
Frequency resolved measurement of longitudinal impedances using transient beam diagnostics

In this paper we present several techniques for characterizing longitudinal impedances based on transient measurements of the growth rates and tune shifts of unstable coupled-bunch modes. These techniques are applicable to measurement of both fundamental and higher-order mode impedances and allow characterization of shunt impedances and quality factors of the HOMs. Methods presented are complementary to lab bench measurements of RF cavities, in that the beam based measurements directly sense the physical impedance in the installed configuration. In contrast to a single-bunch integrated impedance measurement these techniques resolve the impedances in the frequency domain. These methods allow determination of the impedance's unaliased frequency by analyzing synchronous phase transients. Experimental results from ALS and BESSY-II are presented showing the use of these techniques to measure complex impedances.
Transnational Climate Governance and the Global 500: Examining Private Actor Participation by Firm-Level Factors and Dynamics

This article focuses on the Global 500, which are the world’s largest companies by revenue, to examine the factors and dynamics internal to companies that motivate some corporations, but not others...
Lepton CP asymmetries in B decays

Abstract In the decay of ϒ(4S), the decay time distribution of ϒ(4S) → ƒ + X , where ƒ is a final state that B0 or B 0 can decay to, is the sum of the decay time distributions of B 0 → ƒ and B 0 → ƒ . Using this general rule, we estimate sensitivity of single lepton CP violation measurements with respect to that of traditional di-lepton measurements. We find that the sensitivity of the single lepton method is comparable to or better than that of the di-lepton method. The two data samples are largely statistically independent, so that they can be combined to improve sensitivity. The advantage of the single lepton measurement increases for large mixings, which suggests that the single lepton method holds promise for Bs. We also discuss lepton asymmetry measurements on the Z0 peak and in hadron colliders. The achievable sensitivity with the currently available data is already in the range relevant to standard model predictions.
WARM MOLECULAR GAS TRACED WITH CO J = 7 ¿ 6 IN THE GALAXY'S CENTRAL 2 PARSECS: DYNAMICAL HEATING OF THE CIRCUMNUCLEAR DISK

We present an 11" resolution map of the central 2 pc of the Galaxy in the CO J = 7 --> 6 rotational transition. The CO emission shows rotation about Sgr A* but also evidence for noncircular turbulent motion and a clumpy morphology. We combine our data set with available CO measurements to model the physical conditions in the disk. We find that the molecular gas in the region is both warm and dense, with T approx. 200-300 K and n(sub H2) approx. (5-7) x 10(exp 4) cm(exp -3). The mass of warm molecular gas we measure in the central 2 pc is at least 2000 M(solar), about 20 times the UV-excited atomic gas mass, ruling out a UV heating scenario for the molecular material. We compare the available spectral tracers with theoretical models and conclude that molecular gas is heated with magnetohydrodynamic shocks with v approx. 10-20 km s(exp -1) and B approx. 0.3- 0.5 mG. Using the conditions derived with the CO analysis, we include the other important coolants, neutral oxygen and molecular hydrogen, to estimate the total cooling budget of the molecular material. We derive a mass-to-luminosity ratio of approx. 2-3 M(solar)(L(solar)exp -1), which is consistent with the total power dissipated via turbulent decay in 0.1 pc cells with v(sub rms) approx. 15 kilometers per second. These size and velocity scales are comparable to the observed clumping scale and the velocity dispersion. At this rate, the material near Sgr A* is dissipating its orbital energy on an orbital timescale and cannot last for more than a few orbits. Our conclusions support a scenario in which the features near Sgr A* such as the circumnuclear disk and northern arm are generated by infalling clouds with low specific angular momentum.
High dimensional robust M-estimation: asymptotic variance via approximate message passing

In a recent article, El Karoui et al. (Proc Natl Acad Sci 110(36):14557–14562, 2013) study the distribution of robust regression estimators in the regime in which the number of parameters p is of the same order as the number of samples n. Using numerical simulations and ‘highly plausible’ heuristic arguments, they unveil a striking new phenomenon. Namely, the regression coefficients contain an extra Gaussian noise component that is not explained by classical concepts such as the Fisher information matrix. We show here that that this phenomenon can be characterized rigorously using techniques that were developed by the authors for analyzing the Lasso estimator under high-dimensional asymptotics. We introduce an approximate message passing (AMP) algorithm to compute M-estimators and deploy state evolution to evaluate the operating characteristics of AMP and so also M-estimates. Our analysis clarifies that the ‘extra Gaussian noise’ encountered in this problem is fundamentally similar to phenomena already studied for regularized least squares in the setting $$n<p$$ .
Formación de capital social para fortalecer la institucionalización de la gobernabilidad

The aim of this paper is to analyze some implications of popular social movements as an "expression" of gobernability and the social capital formation to foster institutionalization of gobernability. At the same time that conclusions are obtained, some advances are formulated.
Sleep matters: sleep functioning and course of illness in bipolar disorder.

Abstract Background Few studies have prospectively examined the relationships of sleep with symptoms and functioning in bipolar disorder. Methods The present study examined concurrent and prospective associations between total sleep time (TST) and sleep variability (SV) with symptom severity and functioning in a cohort of DSM-IV bipolar patients (N = 468) participating in the National Institute of Mental Health Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD), all of whom were recovered at study entry. Results Concurrent associations at study entry indicated that shorter TST was associated with increased mania severity, and greater SV was associated with increased mania and depression severity. Mixed-effects regression modeling was used to examine prospective associations in the 196 patients for whom follow-up data were available. Consistent with findings at study entry, shorter TST was associated with increased mania severity, and greater SV was associated with increased mania and depression severity over 12 months. Discussion These findings highlight the importance of disrupted sleep patterns in the course of bipolar illness.
Techniques for improved convergence in neighboring optimum guidance

Neighboring optimum feedback guidance to motivate min-distance lookup parameter determined by minimizing metric function of perturbed state and reference trajectory
Entrepreneurship and Bank Credit Availability

The literature is divided on the expected effects of increased competition and consolidation in the financial sector on the supply of credit to relationship borrowers. This paper tests whether policy changes fostering competition and consolidation in U.S. banking helped or harmed entrepreneurs. We find that the rate of new incorporations increases following deregulation of branching restrictions, and that deregulation reduces the negative effect of concentration on new incorporations. We also find the formation of new incorporations increases as the share of small banks decreases, suggesting that diversification benefits of size outweigh the possible comparative advantage small banks may have in forging relationships. OVER THE PAST TWO DECADES, the U.S. financial sector has been reshaped by rapid technological innovation and deregulation. In the 1970s, traditional financial intermediaries, mainly banks, provided the lion's share of credit to nonfinancial companies. At that time, banks had the advantage because they were protected from competitive pressures; price competition was limited by Regulation Q, and entry into banking markets was limited by restrictions on in-state branching and interstate banking. All of this changed over the past 25 years. Starting in the latter half of the 1970s, the U.S. banking system began to be reshaped, both by technological innovations and by the removal of many of these constraining regulations. In the early 1980s, for example, interest rate ceilings were largely removed, allowing banks to compete more vigorously for funds. New technologies like the automated teller machine also enhanced competition within banking, and innovations such as the cash management account offered by nonbank financial companies enhanced competitive pressures from outside the indus
Riemannian gauge theory and charge quantization

In a traditional gauge theory, the matter fields a and the gauge fields Acμ are fundamental objects of the theory. The traditional gauge field is similar to the connection coefficient in the riemannian geometry covariant derivative, and the field-strength tensor is similar to the curvature tensor. In contrast, the connection in riemannian geometry is derived from the metric or an embedding space. Guided by the physical principal of increasing symmetry among the four forces, we propose a different construction. Instead of defining the transformation properties of a fundamental gauge field, we derive the gauge theory from an embedding of a gauge fiber F = n or F = n into a trivial, embedding vector bundle = N or = N where n$>N>n. Our new action is symmetric between the gauge theory and the riemannian geometry. By expressing gauge-covariant fields in terms of the orthonormal gauge basis vectors, we recover a traditional, SO(n) or U(n) gauge theory. In contrast, the new theory has all matter fields on a particular fiber couple with the same coupling constant. Even the matter fields on a 1 fiber, which have a U(1) symmetry group, couple with the same charge of ±q. The physical origin of this unique coupling constant is a generalization of the general relativity equivalence principle. Because our action is independent of the choice of basis, its natural invariance group is GL(n,) or GL(n,). Last, the new action also requires a small correction to the general-relativity action proportional to the square of the curvature tensor.
On obtaining pseudorandomness from error-correcting codes

A number of recent results have constructed randomness extractors and pseudorandom generators (PRGs) directly from certain error-correcting codes. The underlying construction in these results amounts to picking a random index into the codeword and outputting m consecutive symbols (the codeword is obtained from the weak random source in the case of extractors, and from a hard function in the case of PRGs). We study this construction applied to general cyclic error-correcting codes, with the goal of understanding what pseudorandom objects it can produce. We show that every cyclic code with sufficient distance yields extractors that fool all linear tests. Further, we show that every polynomial code with sufficient distance yields extractors that fool all low-degree prediction tests. These are the first results that apply to univariate (rather than multivariate) polynomial codes, hinting that Reed-Solomon codes may yield good randomness extractors. Our proof technique gives rise to a systematic way of producing unconditional PRGs against restricted classes of tests. In particular, we obtain PRGs fooling all linear tests (which amounts to a construction of e-biased spaces), and we obtain PRGs fooling all low-degree prediction tests.
Gaussian and non-Gaussian speckle fluctuations in the diffusing-wave spectroscopy signal of a coarsening foam

All previous applications of diffusing-wave spectroscopy to aqueous foams have relied on the assumption that the electric field of the detected light is a Gaussian random variable and hence that the Siegert relation applies. We test this crucial assumption by simultaneous measurement of both second- and third-order temporal intensity correlations. We find that the electric field is Gaussian for typical experimental geometries equivalent to illumination and detection with a plane wave, both for backscattering and transmission through an optically thick slab. However, we find that the Gaussian character breaks down for point-in-point-out backscattering geometries in which the illumination spot size is not sufficiently large in comparison with the size of the intermittent rearrangement events.
Curbside recycling: Waste resource or waste of resources?

In this paper, we address the often contentious debate over state and local recycling policy by carefully estimating the social net benefit of curbside recycling. Benefits are estimated using household survey data from over 4,000 households across 40 western U.S. cities. We calibrate household willingnesstopay for hypothetical bias using an innovative experimental design that contrasts stated and revealed preferences. Cost estimates are compiled from previous studies by the U.S. Environmental Protection Agency and the Institute for Local Self Reliance, and from indepth interviews with recycling coordinators in our sampled cities. Across our sample of cities, we find that the estimated mean social net benefit of curbside recycling is almost exactly zero. On a citybycity basis, however, our social netbenefit analysis often makes clear predictions about whether a curbside recycling program is an efficient use of resources. Surprisingly, several curbside recycling programs in our sample appear to be inefficient. © 2006 by the Association for Public Policy Analysis and Management.
Design and synthesis of a β-amino phosphotyrosyl mimetic suitably protected for peptide synthesis

Abstract Mimetics of phosphotyrosine (pTyr) such as phosphonomethylphenylalanine (Pmp) have traditionally retained α-amino functionality. However, β-amino acids represent isomeric variants, which may exhibit properties that are distinct from the parent. Reported herein is the first β-amino pTyr mimetic (Pmp β ) bearing protection suitable for peptide synthesis. Preparation of Pmp β was accomplished enantioselectively in 43% overall yield from commercially available 4-vinylbenzyl chloride.
Affine Hecke algebras and generalized standard Young tableaux

Abstract This paper introduces calibrated representations for affine Hecke algebras and classifies and constructs all finite-dimensional irreducible calibrated representations. The primary technique is to provide indexing sets for controlling the weight space structure of finite-dimensional modules for the affine Hecke algebra. Using these indexing sets we show that (1) irreducible calibrated representations are indexed by skew local regions, (2) the dimension of an irreducible calibrated representation is the number of chambers in the local region, (3) each irreducible calibrated representation is constructed explicitly by formulas which describe the action of the generators of the affine Hecke algebra on a specific basis in the representation space. The indexing sets for weight spaces are generalizations of standard Young tableaux and the construction of the irreducible calibrated affine Hecke algebra modules is a generalization of A. Young's seminormal construction of the irreducible representations of the symmetric group. In this sense Young's construction has been generalized to arbitrary Lie type.
An antiinflammatory and reactive oxygen species suppressive effects of an extract of Polygonum cuspidatum containing resveratrol.

Background: Resveratrol have been shown to exert an antiinflammatory and antiaging effects in vitro and in animal models. Objective: The objective of the study was to investigate the effect of a Polygonum cuspidatum extract (PCE) containing resveratrol on oxidative and inflammatory stress in normal subjects. Research Design and Methods: Two groups (10 each) of normal-weight healthy subjects were randomized to placebo or PCE containing 40 mg resveratrol daily for 6 wk. Fasting blood samples were obtained prior to and after treatment at 1, 3, and 6 wk. Mononuclear cells were prepared for reactive oxygen species generation, RNA isolation, nuclear extract, and total cell homogenate preparation. Indices of oxidative and inflammatory stress, suppressor of cytokine signaling-3, phosphotyrosine phosphatase-1B, jun-N-terminal kinase-1, and inhibitor of κB-kinase-β were measured by RT-PCR and Western blotting. Results: The extract induced a significant reduction in reactive oxygen species generation, the expression of p47phox, intranuclear nuclear factor-κB binding, and the expression of jun-N-terminal kinase-1, inhibitor of κB-kinase-β, phosphotyrosine phosphatase-1B, and suppressor of cytokine signaling-3 in mononuclear cells when compared with the baseline and the placebo. PCE intake also suppressed plasma concentrations of TNF-α, IL-6, and C-reactive protein. There was no change in these indices in the control group given placebo. Conclusions: The PCE-containing resveratrol has a comprehensive suppressive effect on oxidative and inflammatory stress.
Continuous delay regulator for controlling recording errors

The principle that tracing and tracking errors arise solely from delay-modulation processes has not found wide application for controlling these errors, because of device imperfections. These can be overcome by use of a regulation principle. Regulation can also be used in a switching-synthesis scheme, achieving continuous delay control without delay lines. The regulation principle invoked is that of the phase-locked loop. The switching-synthesis scheme is a sampled-data analog of the phase-locked loop. Rational design approaches are indicated.
Solution to Darwin's dilemma: Discovery of the missing Precambrian record of life

In 1859, in On the Origin of Species, Darwin broached what he regarded to be the most vexing problem facing his theory of evolution-the lack of a rich fossil record predating the rise of shelly invertebrates that marks the beginning of the Cambrian Period of geologic time ( approximately 550 million years ago), an "inexplicable" absence that could be "truly urged as a valid argument" against his all embracing synthesis. For more than 100 years, the "missing Precambrian history of life" stood out as one of the greatest unsolved mysteries in natural science. But in recent decades, understanding of life's history has changed markedly as the documented fossil record has been extended seven-fold to some 3,500 million years ago, an age more than three-quarters that of the planet itself. This long-sought solution to Darwin's dilemma was set in motion by a small vanguard of workers who blazed the trail in the 1950s and 1960s, just as their course was charted by a few pioneering pathfinders of the previous century, a history of bold pronouncements, dashed dreams, search, and final discovery.
Transonic Airfoil Shape Optimization in Preliminary Design Environment

A modified profile optimization method using a smoothest shape modification strategy (POSSEM) is developed for airfoil shape optimization in a preliminary design environment. POSSEM is formulated to overcome two technical diculties frequently encountered when conducting multipoint airfoil optimization within a high-resolution design space: the generation of undesirable optimal airfoil shapes due to high frequency components in the parametric geometry model and significant degradation in the o-design performance. To demonstrate the usefulness of POSSEM in a preliminary design environment, a design competition was conducted with the objective of improving a fairly well-designed baseline airfoil at four transonic flight conditions without incurring any o-design performance degradation. Independently, two designs were generated from the inverse design tool CDISC, while a third design was generated from POSSEM using over 200 control points of a cubic B-spline curve representation of the airfoil as design variables for the shape optimization. Pros and cons of all the airfoil designs are documented along with in-depth analyses of simulation results. The POSSEM design exhibits a fairly smooth curvature and no degradation in the o-design performance. Moreover, it has the lowest average drag among the three designs at the design conditions, as evaluated from three dierent flow solvers. This study demonstrates the potential of POSSEM as a practical airfoil optimization tool for use in a preliminary design environment. The novel ideas used in POSSEM, such as the smoothest shape modification and modified profile optimization strategies, are applicable to minimizing aircraft drag at multiple flight conditions.
High-temperature superconductors: their potential for utility applications

A number of proposed applications of superconductivity for the electric utility sector are described. The current status of their development as of April 1990 is summarized, and the potential impact of the successful development of high-temperature superconductors (HTSCs) is discussed. Performance goals for development of HTSCs are presented and compared with their current status. Applications discussed include large-scale generators, motors, transmission lines, magnetic storage, transformers, power electronics, and fault-current limiters. >
Contexts—a partitioning concept for hypertext

Hypertext systems provide good information management support for a wide variety of documentation efforts. These efforts range from developing software to writing a book. However, existing hypertext systems provide poor support for collaboration among teams of authors. This paper starts by briefly describing properties of several existing hypertext systems. Then several models for forming partitions in a hypertext database are examined and contexts, a partitioning scheme that supports multiperson cooperative efforts, are introduced. The semantic issues involved in defining contexts are explored in detail.
Chromatin loops as modulators of enhancer-promoter interactions in their vicinity

The classic model of eukaryotic gene expression requires direct spatial contact between a distal enhancer and a proximal promoter. However, recent chromosome conformation capture studies (e.g. Hi-C) show that enhancer and promoters are embedded in a complex network of cell-type specific looping interactions. Here we investigate whether, and to what extent, looping interactions between elements in the vicinity of an enhancer-promoter pair can influence the frequency of enhancer-promoter contacts. Our polymer simulations show that a chromatin loop formed by elements flanking either an enhancer or a promoter suppresses enhancer-promoter interactions, working as a topological insulator. A loop formed by elements located in the region between an enhancer and a promoter, on the contrary, facilitates their interactions. We find that these two consequences of chromatin loops have different genomic extents, with facilitation being a local effect and insulation persisting over a large range of genomic distances. Overall, our results show that looping interactions which do not directly involve an enhancer-promoter contact can nevertheless significantly modulate their interactions. This illustrates the intricate effects that local chromatin organization can have on gene expression.
Regularity of the density for the stochastic heat equation

We study the smoothness of the density of a semilinear heat equation with multiplicative spacetime white noise. Using Malliavin calculus, we reduce the problem to a question of negative moments of solutions of a linear heat equation with multiplicative white noise. Then we settle this question by proving that solutions to the linear equation have negative moments of all orders.
Nominal shocks and real exchange rates: Evidence from two centuries

Abstract This paper employs structural vector autoregression methods to examine the contribution of real and nominal shocks to real exchange rate movements using two hundred and seventeen years of data from Britain and the United States. Shocks are identified with long-run restrictions. The long time series makes possible an investigation of how the role of nominal shocks has evolved over time due to changes in the shock processes or to structural changes in the economy which might alter how a shock is transmitted to the real exchange rate. The sample is split at 1913, which is the end of the classical gold standard period, the last of the monetary regimes of the 19th century. The earlier subsample (1795–1913) shows a much stronger role for nominal shocks in explaining real exchange rate movements than the later subsample (1914–2010). Counterfactual analysis shows that the difference between the two periods is mainly due to the size of the nominal shocks rather than structural changes in the economy. These findings are consistent with the view that the financial instability and frequent deflation of the 19th century had real economic effects.
Fullerenes and Related Molecules as Studied by Solid State NMR

The sections in this article are 1 Introduction 2 History of Fullerene Discovery 3 Studies on Pure C60 4 Studies on Pure C70 5 Studies on Pure Higher Fullerenes 6 Studies on Nanotubes 7 Studies on the Intercalation Complexes of Fullerenes 8 Concluding Remarks 9 Biographical Sketch
Strategy-Proofness and the Tops-Only Property

A social choice function satisfies the tops-only property if the cho- sen alternative only depends on each person's report of his most-preferred alternatives on the range of this function. On many domains, strategy- proofness implies the tops-only property, provided that the range of the social choice function satisfies some regularity condition. The existing proofs of this result are model specific. In this article, a general proof strategy is proposed for showing that a strategy-proof social choice function satisfies the tops-only property when everyone has the same set of admissible preferences.
Non-Commutative Sylvester's Determinantal Identity

Sylvester's identity is a classical determinantal identity with a simple linear algebra proof. We present combinatorial proofs of several non-commutative extensions, and find a $\beta$-extension that is both a generalization of Sylvester's identity and the $\beta$-extension of the quantum MacMahon master theorem.
Irrigation Technology Adoption and Gains from Water Trading under Asymmetric Information

We develop a water allocation and irrigation technology adoption model under the prior appropriation doctrine with asymmetric information among heterogeneous farmers and between farmers and water authorities. We find that adverse selection reduces the adoption of modern irrigation technology. We also show that even with asymmetric information, incentives for water trade exist and lead to additional technology adoption with gains to all parties. This suggests that under asymmetric information, a thin secondary market improves the allocation of water resources and induces additional adoption of modern irrigation technologies.
Theories of Heterogeneous Firms and Trade

This article reviews the recent theoretical literature on heterogeneous firms and trade, which emphasizes firm selection into international markets and reallocations of resources across firms. We discuss the empirical challenges that motivated this research and its relationship to traditional trade theories. We examine the implications of firm heterogeneity for comparative advantage, market size, aggregate trade, the welfare gains from trade, and the relationship between trade and income distribution. Although a number of studies examine the endogenous response of firm productivity to trade liberalization, modeling internal firm organization and the origins of firm heterogeneity remain interesting areas of ongoing research.
Geometrical Effects on Shielding Effectiveness at Low Frequencies

A frequent approach to computing the magnetic shielding effectiveness of enclosures is to consider the effect of a plane wave impinging on a sheet of infinite extent. This permits an analysis based on a transmissionline characterization. However, when the wavelength is large compared to the dimensions of the enclosure, other analytical approaches provide better results. It has been shown that the current distribution on a box-like object scattering in the Rayleigh region tends to concentrate at the edges and corners of the box. This leads to concentrations of the magnetic field in the vicinity of edges and corners both inside and outside the enclosure. Since the effects of the current concentrations are localized, the magnetic shielding problem can be simplified by assuming a uniform current distribution on the exterior of the enclosure. Under this assumption the socalled ?circuit approach? can be applied. The box-like enclosure is characterized as a series of shorted turns which shield a sensor within the enclosure. Based on the geometry, the mutual and leakage impedances between the source and sensor are used to compute the magnetic shielding effectiveness. This approach yields valid results for shields constructed of either wire mesh or sheet metal. It can also be extended to account for degradation due to bad bonds. A comparison of results, both transient and steady state, of the circuit approach and scattering theory show close agreement for spherical enclosures.
Accumulate-repeat-accumulate-accumulate-codes

Inspired by recently proposed accumulate-repeat-accumulate (ARA) codes (Abbasfar et al. (2004)), in this paper we propose a channel coding scheme called accumulate-repeat-accumulate-accumulate (ARAA) codes. These codes can he seen as serial turbo-like codes or as a subclass of low density parity check (LDPC) codes, and they have a projected graph or protograph representation, this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded repeat-and-accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-1/2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.
An olefination-based route to unsaturated hydroperoxides

Abstract Wittig or Horner-Emmons olefination of peroxy-substituted aldehydes provides an efficient route to unsaturated hydroperoxides.
Local Banking Competition and Efficiency in the Presence of Offshore Financial Institutions: Evidence from the Caribbean

Offshore banking is a significant aspect of the financial environment in some Caribbean Islands. The objective of this paper is to identify whether domestic banks located in Caribbean offshore centers operate any differently from domestic banks located in islands that do not host offshore banking. Balance sheets and income statements between 1993 and 2004 are used to measure the level of competitiveness and efficiency of banking activity. The results show that domestic banks located in Caribbean offshore financial centers operate in a less competitive manner and are less efficient in their role in providing financial intermediation than local commercial banks located in non-offshore banking islands.
Reconstructing specimens using DIC microscope images

Differential interference contrast (DIC) microscopy is a powerful visualization tool used to study live biological cells. Its use, however, has been limited to qualitative observations. The inherent nonlinear relationship between the object properties and the image intensity makes quantitative analysis difficult. Toward quantitatively measuring optical properties of objects from DIC images, we develop a method to reconstruct the specimen's optical properties over a three-dimensional (3-D) volume. The method is a nonlinear optimization which uses hierarchical representations of the specimen and data. As a necessary tool, we have developed and validated a computational model for the DIC image formation process. We test our algorithm by reconstructing the optical properties of known specimens.
Scalability of surface PM Machines with concentrated windings designed to achieve wide speed ranges of constant-power operation

Previous work has shown that it is possible to design surface permanent magnet (SPM) synchronous machines, using fractional-slot concentrated windings to achieve wide speed ranges of constant-power operation. A closed-form analytical technique is now available to rapidly analyze candidate SPM machine designs using concentrated windings and tune them to meet the critical condition for optimal flux weakening. This analytical tool is used to demonstrate that optimal flux weakening can be achieved in SPM machines that are varied over wide ranges in several key dimensions including machine pole numbers, diameter-to-length aspect ratios, and output power ratings. Performance requirements for a 6-kW direct-drive automotive starter/alternator machine are used as the starting point for the scalability investigation. Finite element analysis results are presented to confirm the validity of key results in this investigation.
Computer Aided Design of Wide-Band Integrated Microwave Transistor Amplifiers on High Dielectric Substrates

The problem of wide bandwidth and flat in-band gain response for microwave transistor amplifiers has been reduced to the optimization of a number of important variables from computer prepared design charts. Through the general flexibility of the computer-generated data, a large variety of amplifier responses are possible using distributed circuit matching networks. As experimental verification of the overall design procedure, single-stage and two-stage octave wide transistor amplifiers were fabricated on 1inch by 1inch and 1inch by 1/2 inch 20 mil thick alumina, respectively. The experimental data gained from these units showed excellent correlation with the computer predicted response.
The LASSO Risk for Gaussian Matrices

We consider the problem of learning a coefficient vector xο ∈ RN from noisy linear observation y = Axo + ∈ Rn. In many contexts (ranging from model selection to image processing), it is desirable to construct a sparse estimator x. In this case, a popular approach consists in solving an l1-penalized least-squares problem known as the LASSO or basis pursuit denoising. For sequences of matrices A of increasing dimensions, with independent Gaussian entries, we prove that the normalized risk of the LASSO converges to a limit, and we obtain an explicit expression for this limit. Our result is the first rigorous derivation of an explicit formula for the asymptotic mean square error of the LASSO for random instances. The proof technique is based on the analysis of AMP, a recently developed efficient algorithm, that is inspired from graphical model ideas. Simulations on real data matrices suggest that our results can be relevant in a broad array of practical applications.
Selection of Optimal Spectral Sensitivity Functions for Color Filter Arrays

A color image meant for human consumption can be appropriately displayed only if at least three distinct color channels are present. Typical digital cameras acquire three-color images with only one sensor. A color filter array (CFA) is placed on the sensor such that only one color is sampled at a particular spatial location. This sparsely sampled signal is then reconstructed to form a color image with information about all three colors at each location. In this paper, we show that the wavelength sensitivity functions of the CFA color filters affect both the color reproduction ability and the spatial reconstruction quality of recovered images. We present a method to select perceptually optimal color filter sensitivity functions based upon a unified spatial-chromatic sampling framework. A cost function independent of particular scenes is defined that expresses the error between a scene viewed by the human visual system and the reconstructed image that represents the scene. A constrained minimization of the cost function is used to obtain optimal values of color-filter sensitivity functions for several periodic CFAs. The sensitivity functions are shown to perform better than typical RGB and CMY color filters in terms of both the s-CIELAB ΔE error metric and a qualitative assessment.
Symphony: synchronous two-phase rate and power control in 802.11 WLANs

Adaptive transmit power control in 802.11 wireless LANs (WLANs) on a per-link basis helps increase network capacity and improves battery life of WiFi-enabled mobile devices. However, it faces the following challenges: 1) it can exacerbate receiver-side interference and asymmetric channel access; 2) it can incorrectly lead to lowering the data rate of a link; 3) mobility-induced channel variations at short timescales make detecting and avoiding these problems more complex. Despite substantial prior research, state-of-the-art solutions lack comprehensive techniques to address the above problems. In this paper, we design and implement Symphony, a synchronous two-phase rate and power control system whose agility in adaptation enables us to systematically address the three problems while maximizing the benefits of power control on a per-link basis. We implement Symphony in the Linux MadWifi driver and show that it can be realized on hardware that supports transmit power control with no modifications to the 802.11 MAC, thereby fostering immediate deployability. Our extensive experimental evaluation on a real testbed in an office environment demonstrates that Symphony : 1) enables up to 80% of the clients in three different cells to settle at 50%-94% lower transmit power than a per-cell power control solution; 2) increases network throughput by up to 50% across four realistic deployment scenarios; 3) improves the throughput of asymmetry-affected links by 300%; and 4) opportunistically reduces the transmit power of mobile clients running VOIP calls by up to 97% while only causing a negligible degradation of voice quality.
Error and work estimates for high‐order elements

Error and work estimates for high order elements are derived. The comparison of error and work estimates shows that for relative accuracy in the 1% range, which is typical of engineering interest, it may prove very difficult to improve on linear elements. As expected, the estimates also show that the optimal order of element in terms of work and storage demands depends on the desired relative accuracy. The comparison of work estimates for high order elements and their finite difference counterparts reveals a work-ratio of several orders of magnitude. It thus becomes questionable if general geometric flexibility via micro-unstructured grids is worth such a high cost.
CREB/ATF-dependent T cell receptor–induced FoxP3 gene expression: a role for DNA methylation

Regulatory T cells (T reg cells) are a population of CD4+ T cells that limit immune responses. FoxP3 is a master control transcription factor for development and function of these cells, but its regulation is poorly understood. We have identified a T cell receptor–responsive enhancer in the FoxP3 first intron that is dependent on a cyclic-AMP response element binding protein (CREB)/activating transcription factor (ATF) site overlapping a CpG island. Methylation of this island inversely correlates with CREB binding and FoxP3 expression. Interestingly, transforming growth factor-β, which induces T reg cell formation, decreases methylation of the CpG island and increases FoxP3 expression. Similarly, inhibiting methylation with 5-azacytidine or knocking down the DNA methyltransferase Dnmt1 also induces FoxP3 expression. Conversely, methylation of the CpG island, which decreases CREB binding or expression of dominant-negative CREB, decreases FoxP3 gene expression. Thus, T cell receptor–induced FoxP3 expression in T reg cells is controlled both by sequence-specific binding of CREB/ATF and by DNA methylation of a CpG island.
Plasticity, evolvability, and modularity in RNA.

RNA folding from sequences into secondary structures is a simple yet powerful, biophysically grounded model of a genotype-phenotype map in which concepts like plasticity, evolvability, epistasis, and modularity can not only be precisely defined and statistically measured but also reveal simultaneous and profoundly non-independent effects of natural selection. Molecu- lar plasticity is viewed here as the capacity of an RNA sequence to assume a variety of energeti- cally favorable shapes by equilibrating among them at constant temperature. Through simulations based on experimental designs, we study the dynamics of a population of RNA molecules that evolve toward a predefined target shape in a constant environment. Each shape in the plastic repertoire of a sequence contributes to the overall fitness of the sequence in proportion to the time the sequence spends in that shape. Plasticity is costly, since the more shapes a sequence can assume, the less time it spends in any one of them. Unsurprisingly, selection leads to a reduction of plasticity (environmental canalization). The most striking observation, however, is the simulta- neous slow-down and eventual halting of the evolutionary process. The reduction of plasticity entails genetic canalization, that is, a dramatic loss of variability (and hence a loss of evolvability) to the point of lock-in. The causal bridge between environmental canalization and genetic canali- zation is provided by a correlation between the set of shapes in the plastic repertoire of a sequence and the set of dominant (minimum free energy) shapes in its genetic neighborhood. This statisti- cal property of the RNA genotype-phenotype map, which we call plastogenetic congruence, traps populations in regions where most genetic variation is phenotypically neutral. We call this phe- nomenon neutral confinement. Analytical models of neutral confinement, made tractable by the assumption of perfect plastogenetic congruence, formally connect mutation rate, the topography of phenotype space, and evolvability. These models identify three mutational regimes: that corre- sponding to neutral confinement, an exploration threshold corresponding to a breakdown of neu- tral confinement with the simultaneous persistence of the dominant phenotype, and a classic error threshold corresponding to the loss of the dominant phenotype. In a final step, we analyze the structural properties of canalized phenotypes. The reduction of plasticity leads to extreme modu- larity, which we analyze from several perspectives: thermophysical (melting—the RNA version of a norm of reaction), kinetic (folding pathways—the RNA version of development), and genetic (transposability—the insensitivity to genetic context). The model thereby suggests a possible evo- lutionary origin of modularity as a side effect of environmental canalization. J. Exp. Zool. (Mol. Dev. Evol.) 288:242-283, 2000. © 2000 Wiley-Liss, Inc.
Galaxy subgroups in galaxy clusters

Galaxies that fall into clusters as a part of the same infall halo can retain correlations due to their shared origin. N-body simulations are used to study properties of such galaxy subgroups within clusters, including their richnesses and prevalence. The sizes, densities and velocity dispersions of all subgroups with ≥8 galaxies are found and compared to those of the host clusters. The largest galaxy subgroup provides a preferred direction in the cluster and is compared to other preferred directions in the cluster. Scatter in cluster mass measurements (via five observables), along ∼96 lines of sight, is compared to the relation of the line of sight to this preferred direction: scatter in cluster velocity dispersion measurements show the strongest correlation. The Dressler-Shectman test is an observational method to detect cluster substructure. This test is applied to the cluster sample to see whether the substructure it identifies is related to these subgroups. The results for any specific line of sight seem noisy; however, clusters with large subgroups tend to have a higher fraction of lines of sight where the test detects substructure.
Integrated optical silicon photodiode array

We consider device design, fabrication, and operation of integrated optical photodiode arrays in which p-i-n junction photodiodes are formed in silicon. A SiO2 layer on silicon serves as the effective substrate for a KPR waveguide. Light is coupled from the waveguide at the detector region either through the evanescent field or by multiple refraction into the detector. The waveguide–photodiode structure is designed so that nearly 100% of the incident optical energy can be absorbed in the photodiode junction depletion region. A device quantum efficiency of 80% is measured compared to a theoretical value of 93%.
The Ultrafast Pathway of Photon-Induced Electrocyclic Ring-Opening Reactions: The Case of 1,3-Cyclohexadiene

The photochemically induced electrocyclic ring-opening reaction of 1,3-cyclohexadiene to 1,3,5-hexatriene serves as a prototype for many important reactions in chemistry and in biological systems. Based on experimental and computational studies, a detailed picture of the reaction has now emerged: Excitation to the Franck-Condon region places the molecule on a steeply repulsive part of the 1B potential energy surface, which propels the molecule in exactly the conrotatory direction that conforms to the Woodward-Hoffmann rules of orbital symmetry. Bypassing a cusp in a symmetry-breaking direction, the wave packet enters the 2A state within 55 fs. It continues to move directly toward the 2A/1A conical intersection, where it crosses in approximately 80 fs to the ground state. This article summarizes the published experimental and theoretical work to describe the current understanding of the reaction while pointing to important questions that remain to be addressed.
Predicting abnormal returns from news using text classification

We show how text from news articles can be used to predict intraday price movements of financial assets using support vector machines. Multiple kernel learning is used to combine equity returns with text as predictive features to increase classification performance and we develop an analytic center cutting plane method to solve the kernel learning problem efficiently. We observe that while the direction of returns is not predictable using either text or returns, their size is, with text features producing significantly better performance than historical returns alone.
Active guidance for a finless rocket using neuroevolution

Finless rockets are more efficient than finned designs, but are too unstable to fly unassisted. These rockets require an active guidance system to control their orientation during flight and maintain stability. Because rocket dynamics are highly non-linear, developing such a guidance system can be prohibitively costly, especially for relatively small-scale rockets such as sounding rockets. In this paper, we propose a method for evolving a neural network guidance system using the Enforced SubPopulations (ESP) algorithm. Based on a detailed simulation model, a controller is evolved for a finless version of the Interorbital Systems RSX-2 sounding rocket. The resulting performance is compared to that of an unguided standard full-finned version. Our results show that the evolved active guidance controller can greatly increase the final altitude of the rocket, and that ESP can be an effective method for solving real-world, non-linear control tasks.