cssi/SciSciGPT-SciSciNet huggingface dataset:
Silver nanocluster containing diamond like carbon

Applying Diamond Like Carbon (DLC) as medical coating has become well established since large scale plasma processes like Plasma Immersion Ion Implantation and Deposition (PIII&D) are available. Now the focus of research lies on systematic modification of certain biological relevant properties and the most recent field of interest turned to generating antimicrobial behaviour. This is desirable for medical tools as well as for different types of medical implants. Since silver and copper are known to provide a bactericidal effect, one tries to introduce clusters of these noble metals into the carbon matrix. The basic principle of the method presented is to convert a metal containing polymer film into DLC by ion bombardment. In this paper the hydrogenated DLC matrix is characterized and the evolution of the metal particles is studied. By means of film composition (RBS/ERD), bonding structure (Raman spectroscopy) and hardness (nanoindentation), the dependency of these material properties on ion species, energy and fluence is investigated. TEM imaging is used to visualize the film structure. Upon ion irradiation of the polymer films, increased density and considerable loss of hydrogen can be observed, which both are controlled by ion fluence and mass. The crosslinking of the carbon network, caused by hydrogen drive out as well as atomic displacements in collision cascades, results in the formation of a-C:H. The silver particles in the film some ion induced growth, but still remain as nanoclusters in the a-C:H matrix. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
The Distribution of ALFALFA Galaxies

The ALFALFA blind HI survey will enable a census of the distribution of gas-rich galaxies in the local Universe. Sensitive to an HI mass of 10**7 solar masses at the distance of the Virgo cluster, ALFALFA will probe the smallest objects locally and provide a new consideration of near-field cosmology. Additionally, with a larger, cosmologically significant sample volume and wider bandwidth than previous blind surveys, a much larger number of detections in each mass bin is possible, with adequate angular resolution to eliminate the need for extensive follow-up observations. This increased sensitivity will greatly enhance the utility of cosmological probles in HI. ALFALFA will eventually measure the correlation function of HI selected galaxies in a large local volume. The larger sample and volume size of the ALFALFA dataset will also robustly measure the HI mass function (HIMF). Here, we present the preliminary results on the distribution of local gas-rich galaxies from a first ALFALFA catalog covering 540 deg**2.
Librarians Do It Differently: Comparative Usability Testing with Students and Library Staff

Usability testing on library search tools was conducted with ten students and eighteen library staff members at Syracuse University. The study addressed three research questions: (1) Do the ways in which librarians carry out search tasks on the library Web site vary from those of student users?; (2) Are those variations indicative of different mental models, i.e. different experience with and knowledge about the content and search tools on the Web site?; and (3) If there are differences, what are the implications of those different models for the usability of the site by students? Participants were tasked by using the library's Web site to locate both known items and items about a subject in the library's collection. The two groups differed in the success with which they were able to complete the tasks, as well as the time used. There were differences in the selection of search tools, the syntax used within the search box, the expectations of how library resources are organized, and the level of persisten...
Maximum noise abatement trajectories.

Minimum noise annoyance trajectories for developing STOL operation procedures are obtained by modulating five control variables in two dimensions. The performance index is formulated such that it explicitly assigns the same relative importance to thrust as it does to distances between discrete listeners and the aircraft. However, using a steepest descent optimization program, results indicate that it is preferable to keep the thrusters at their maximum value to minimize the integrated annoyance rather than to reduce thrust which would lower the instantaneous annoyance. Thrust decreases below its bound only when the instantaneous noise at a listener is limited.
Insolation modeling overview

Abstract This paper gives a summary of some of the major national projects in the area of solar radiation resource assessment. It also discusses the primary solar radiation data sources for the U.S. and the models that were used in developing these sources. Recommendations for appropriate solar radiation resource information for various types of solar system design and analysis needs are given.
Breaking the duality in the return times theorem

We prove Bourgain's return times theorem for a range of exponents p and q that are outside the duality range. An oscillation result is used to prove hitherto unknown almost-everywhere convergence for the signed average analogue of Bourgain's averages
Degree reduction of Bézier simplexes

Abstract The paper describes a degree reduction method for Bezier simplexes with the following properties. Symmetry: the degree reduction method is symmetric with respect to the corner points of the Bezier simplex. Restriction: the degree reduction method restricted to the boundary of a Bezier simplex yields the same result as the boundary of the degree reduced Bezier simplex. Interpolation: the degree reduced simplex of degree e interpolates the value and the first ⌞(e — 1)/2⌟ derivatives at the corner points of the original Bezier simplex. Optimal order of approximation: the order of approximation of the given simplex by the degree reduced simplex is O (h e+1 ) (where h is the diameter of the domain simplex), which is optimal for functional approximation. The method, restricted to Bezier surfaces, yields a new technique for degree reduction which is easy to implement.
Improving Software Diagnosability via Log Enhancement

Diagnosing software failures in the field is notoriously difficult, in part due to the fundamental complexity of troubleshooting any complex software system, but further exacerbated by the paucity of information that is typically available in the production setting. Indeed, for reasons of both overhead and privacy, it is common that only the run-time log generated by a system (e.g., syslog) can be shared with the developers. Unfortunately, the ad-hoc nature of such reports are frequently insufficient for detailed failure diagnosis. This paper seeks to improve this situation within the rubric of existing practice. We describe a tool, LogEnhancer that automatically “enhances” existing logging code to aid in future post-failure debugging. We evaluate LogEnhancer on eight large, real-world applications and demonstrate that it can dramatically reduce the set of potential root failure causes that must be considered while imposing negligible overheads.
Whistler mode turbulence generated by electron beams in earth's bow shock

The Landau and cyclotron growth rates of whistler mode waves in the earth's bow shock are calculated by using electron distribution functions obtained with the fast plasma experiment on ISEE 2. Three electron distribution functions measured within the transition region of the shock are analyzed. These functions spontaneously generate whistler mode waves with plasma rest frame frequencies between about 0.1 and 100 Hz. The wave normal angles of the generated whistlers range from 0 deg to the resonance cone angle. Electromagnetic Landau resonance and/or cyclotron resonance contribute to wave growth over the range of observed velocity distributions. Waves generated by the normal cyclotron resonance have wave vectors directed toward the solar wind, while those generated by the Landau and the anomalous cyclotron resonances have vectors directed toward the magnetosheath. The preditions of the study are in qualitative agreement with observations of whistler mode waves near the earth's bow shock.
Even order snake resonances

We found that the perturbed spin tune due to the imperfection resonance plays an important role in beam depolarization at snake resonances. We also found that even order snake resonances exist in the overlapping intrinsic and imperfection resonances. Due to the perturbed spin tune shift of imperfection resonances, each snake resonance splits into two. >
Studies of einsteinium metal

Thin films of einsteinium metal were prepared by reducing Es/sub 2/O/sub 3/ with lanthanum, distilling the einsteinium metal, and condensing it on carbon substrates supported by electron microscopy grids. The metal deposits were then analyzed by electron diffraction. The results show that vapor-deposited einsteinium metal is divalent and exhibits a fcc phase (a/sub 0/ = 5.75(1)A) very similar to that reported for the expanded form of californium metal.
Applying natural language generation to indicative summarization

The task of creating indicative summaries that help a searcher decide whether to read a particular document is a difficult task. This paper examines the indicative summarization task from a generation perspective, by first analyzing its required content via published guidelines and corpus analysis. We show how these summaries can be factored into a set of document features, and how an implemented content planner uses the topicality document feature to create indicative multidocument query-based summaries.
SAT-Based Complete Don't-Care Computation for Network Optimization

The paper describes an improved approach to Boolean network optimization using internal don't-cares. The improvements concern the type of don't-cares computed, their scope, and the computation method. Instead of the traditionally used compatible observability don't-cares (CODCs), we introduce and justify the use of complete don't-cares (CDC). To ensure the robustness of the don't-care computation for very large industrial networks, an optional windowing scheme is implemented that computes substantial subsets of the CDCs in reasonable time. Finally, we give a SAT-based don't-care computation algorithm that is more efficient than BDD-based algorithms. Experimental results confirm that these improvements work well in practice. Complete don't-cares allow for a reduction in the number of literals compared to the CODCs. Windowing guarantees robustness, even for very large benchmarks on which previous methods could not be applied. SAT reduces the runtime and enhances robustness, making don't-cares affordable for a variety of other Boolean methods applied to the network.
A Nonparametric Approach to Modeling Choice with Limited Data

Choice models today are ubiquitous across a range of applications in operations and marketing. Real-world implementations of many of these models face the formidable stumbling block of simply identifying the “right” model of choice to use. Because models of choice are inherently high-dimensional objects, the typical approach to dealing with this problem is positing, a priori, a parametric model that one believes adequately captures choice behavior. This approach can be substantially suboptimal in scenarios where one cares about using the choice model learned to make fine-grained predictions; one must contend with the risks of mis-specification and overfitting/underfitting. Thus motivated, we visit the following problem: For a “generic” model of consumer choice namely, distributions over preference lists and a limited amount of data on how consumers actually make decisions such as marginal information about these distributions, how may one predict revenues from offering a particular assortment of choices? An outcome of our investigation is a nonparametric approach in which the data automatically select the right choice model for revenue predictions. The approach is practical. Using a data set consisting of automobile sales transaction data from a major U.S. automaker, our method demonstrates a 20% improvement in prediction accuracy over state-of-the-art benchmark models; this improvement can translate into a 10% increase in revenues from optimizing the offer set. We also address a number of theoretical issues, among them a qualitative examination of the choice models implicitly learned by the approach. We believe that this paper takes a step toward “automating” the crucial task of choice model selection. This paper was accepted by Yossi Aviv, operations management.
Observations from Mandatory Livestock Price Reporting for Analysts and Researchers

Mandatory livestock price reporting has changed how prices are reported and used. Reporting has affected the availability of many reports and has added new reports and information. A variety of research issues are facilitated by the scope of new information available. However, the new information often needs to be put into meaningful form for direct use. A brief overview of the evolution and implementation of mandatory price reporting is given. The new price reports are then discussed and compared to voluntary reports. There is enough new information that analysts may be able to make different insights into price formation. Special attention is given to new reports that give insights into the short-run cattle supply situation. While the focus is on cattle reports, swine reports are also briefly discussed.
Simulation of space charge in unbounded geometries

In corona ion devices the electric field distribution is highly dependent on the form of the electrostatic space-charge distribution. In many instances these devices also have essentially unbounded geometries. A numerical technique is presented based on the combined method of charge simulation and the method of characteristics to evaluate fields in such geometries. The numerical procedure utilizes a nonrigid grid structure which, after convergence to a self-consistent solution, is a map of the field lines and equipotential contours. The numerical procedure is applied to a rod-to-plane geometry, and the simulation results show good agreement with experimental data. >
Synthesis, structure, and magnetic properties of two quasi-low-dimensional antiferromagnets, NaMnAsO4 and β-NaCuPO4☆

Abstract Crystals of NaMnAsO4 (1) and β-NaCuPO4 (2) were grown by conventional high-temperature, solid-state methods in molten salt media. The compounds were characterized by single crystal X-ray diffraction and magnetic susceptibility measurements. Compound 1 crystallizes in an orthorhombic lattice with a=10.853(3) A, b=6.383(2) A, c=5.157(2) A, and V=357.2(2) A3; Pnma (No. 62); Z=4, while 2 crystallizes in a monoclinic lattice with a=6.943(1) A, b=8.848(1) A, c=5.013(1) A, β=97.25(1)° and V=305.53(9) A3; P21/n (No. 14); Z=4. The new sodium manganese(II) arsenate is isostructural with LiMnAsO4, which contains single layers of (100) perovskite sheet made of distorted MnO6 octahedra. Sodium copper(II) phosphate adopts a known β-form that possesses linear chains of edge-shared CuO6 octahedra depicting a [4+2] Jahn–Teller distortion. These structurally isolated magnetic layers and chains are incorporated into a three-dimensional lattice via the linkage by closed-shell, non-magnetic oxy anions. Magnetic susceptibility measurements reveal that the title compounds are antiferromagnetic with the negative Weiss constants θ=−76.99 K (1) and −33.85 K (2). At low-temperatures, magnetic susceptibility data feature a field-induced antiferromagnetic-to-ferromagnetic transition. The field dependence studies further indicate that these phenomena could be attributed to metamagnetism and a spin-flop transition, respectively. The current work in the exploratory synthesis of quasi-low-dimensional TM-based oxy compounds gives a new perspective to the continued investigation of experimental and theoretical developments of magnetic models.
Bayesian optimal no-deficit mechanism design

One of the most fundamental problems in mechanism design is that of designing the auction that gives the optimal profit to the auctioneer. For the case that the probability distributions on the valuations of the bidders are known and independent, Myerson [15] reduces the problem to that of maximizing the common welfare by considering the virtual valuations in place of the bidders' actual valuations. The Myerson auction maximizes the seller's profit over the class of all mechanisms that are truthful and individually rational for all the bidders; however, the mechanism does not satisfy ex post individual rationality for the seller. In other words, there are examples in which for certain sets of bidder valuations, the mechanism incurs a loss. We consider the problem of merging the worst case no-deficit (or ex post seller individual rationality) condition with this average case Bayesian expected profit maximization problem. When restricting our attention to ex post incentive compatible mechanisms for this problem, we find that the Myerson mechanism is the optimal no-deficit mechanism for supermodular costs, that Myerson merged with a simple thresholding mechanism is optimal for all-or-nothing costs, and that neither mechanism is optimal for general submodular costs. Addressing the computational side of the problem, we note that for supermodular costs the Myerson mechanism is NP-hard to compute. Furthermore, we show that for all-or-nothing costs the optimal thresholding mechanism is NP-hard to compute. Finally, we consider relaxing the ex post incentive compatibility constraint and show that there is a Bayesian incentive compatible mechanism that achieves the same expected profit as Myerson, but never incurs a loss.
FISCAL CONSEQUENCES FOR MEXICO OF ADOPTING THE DOLLAR

Dollarization implies a reduction in the menu of assets available to the government and to the private sector in managing risk. Whatever the gains from dollarization, the costs of reducing the asset menu need to be weighed against them. This paper presents models, one a simple generalization of a well-known model of tax smoothing by Ba1ao, in which these costs are explicit. Along the way, it suggests that there is likely to be no reduction in interest costs to the government from dollarization. RECENTLY ECONOMISTS have been paying increasing attention to a dynamic general equilibrium approach to the theory of the price level that is often called the fiscal theory of the price level, or FTPL. This way of thinking emphasizes the role of fiscal and monetary policy in determining the risk and return properties of government liabilities. It is particularly useful in analyzing proposals for large-scale institutional changes that imply shifts in monetary and fiscal policies. When dollarization is considered from this perspective, some disadvantages are brought to light that may not be so apparent from other points of view. Section 1 below lays out the main ideas of FTPL. Section 2 displays a model that extends an earlier one of Barro's to argue that optimal fiscal policy will use surprise inflation to achieve lower deadweight tax loss than would otherwise be possible. Section 3 considers the composition of government liabilities along the lines of the theory of corporate finance, asking if dollarization will reduce the cost of funds. Section 4 presents annual estimates of the unanticipated returns to holders of U.S. government debt, to show that these are substantial and are to some extent timed to match legitimate periods of fiscal stress, as the optimality theory of section 2 would suggest. Section S discusses the lendel of-last-resort function and its connection to these fiscal issues. Section 6 briefly discusses some alternatives to pure dollarization. In our concluding section 7 we sum up, finding much to worry about in the prospect of dollarization.
Dollar Dominance, Euro Aspirations: Recipe for Discord?

After nearly a century of dominance of the international monetary system, has the US dollar finally met its match in the euro? When Europe's economic and monetary union (EMU) came into existence in 1999, many observers predicted that the euro would soon join America's greenback at the peak of global finance. Achievements, however, have fallen short of aspiration. After an initial spurt of enthusiasm, international use of the euro actually appears now to be levelling off, even stalling, and so far seems confined largely to a limited range of market sectors and regions. The euro has successfully attained a place second only to the greenback – but it remains, and is likely to remain, a quite distant second without a determined effort by EMU authorities to promote their money's global role. The temptation will surely be great. In practical terms, it is difficult to imagine that EMU authorities will refrain entirely from trying to promote a greater role for the euro. But that, in turn, could turn out to be a recipe for discord with the United States, which has never made any secret of its commitment to preserving the greenback's worldwide dominance. A struggle for monetary leadership could become a source of sustained tensions in US–European relations. Fortunately, however, there seems relatively little risk of a destabilizing escalation into outright geopolitical conflict.
A unified approach for calculating error rates of linearly modulated signals over generalized fading channels

We present a unified analytical framework to determine the exact average symbol-error rate (SER) of linearly modulated signals over generalized fading channels. The results are applicable to systems employing coherent demodulation with maximal-ratio combining multichannel reception. The analyses assume independent fading paths, which are not necessarily identically distributed. In all cases, the proposed approach leads to an expression of the average SER involving a single finite-range integral, which can be easily computed numerically. In addition, as special cases, SER expressions for single-channel reception are obtained. These expressions reduce to well-known solutions, give alternative (often simpler) expressions for previous results, or provide new formulas that are either closed-form expressions or simple to compute numerically.
Why Don't More Households File for Bankruptcy?

A much higher fraction of U.S. households would benefit financially from bankruptcy than actually file. While the current bankruptcy filing rate is about 1% of households each year, I calculate that at least 15% of households would benefit financially from filing and the actual figure would be several times higher if most households plan in advance for the possibility of filing. Two explanations are explored for why more households don’t file for bankruptcy. The first is a model of the interaction between creditors’ remedies against debtors who default and the debtors’ right to file for bankruptcy. The model implies that some debtors default but do not file for bankruptcy, even though they would benefit financially from doing so, because creditors do not always attempt to collect. The other explanation involves the option value of bankruptcy. Many debtors who would not benefit from filing immediately gain from having the option to file in the future. I calculate the value of the option for typical households and show that it can be very valuable, particularly for households that have high variance of the return to net wealth and households that live in states with high bankruptcy exemption levels.
The two poverty enlightenments: historical insights from digitized books spanning three centuries

Word searches of Google's library of digitized books suggest that there have been two “Poverty Enlightenments” since 1700, one near the end of the 18th century and the second near the end of the 20th. The historical literature suggests that only the second came with a widespread belief that poverty could and should be eliminated. After the first Poverty Enlightenment, references to “poverty” (as a percentage of all words) were on a trend decline until 1960, after which there was a striking resurgence of interest, which came with rising attention to economics and more frequent references to both general and specific policies relevant to poverty. Developing countries also became more prominent in the literature. Both Enlightenments came with greater attention to human rights. The written record reflects the push-back against government intervention and the retreat from leftist economics and politics since the late 1970s. Although many debates from 200 years ago continue today, there is little sign that the modern revival of the classical 19th century views on the limitations of government has come with a revival of the complacency about poverty that was common early in that century.
Detection of a Hot Subdwarf Companion to the Be Star FY Canis Majoris

The rapid rotation of Be stars may be caused in some cases by past mass and angular momentum accretion in an interacting binary in which the mass donor is currently viewed as a small, hot subdwarf stripped of its outer envelope. Here we report on the spectroscopic detection of such a subdwarf in the Be binary system FY Canis Majoris from the analysis of data acquired by the IUE spacecraft and KPNO Coude Feed Telescope over the course of 16 and 21 yr, respectively. We present a double-lined spectroscopic orbit for the binary based on radial velocities from the IUE spectra and use the orbital solutions with a Doppler tomography algorithm to reconstruct the components' UV spectra. The subdwarf is hot (Teff = 45 ± 5 kK) and has a mass of about 1.3 M☉ and a radius of about 0.6 R☉. It contributes about 4% as much flux as the Be star does in the FUV. We also present observations of the Hα and He I λ6678 emission features that are formed in the circumstellar disk of the Be star. Orbital flux and velocity variations in the He I λ6678 profile indicate that much of the emission forms along the disk rim facing the hot subdwarf where the disk is probably heated by the incident radiation from the subdwarf. A study of the FUV infall shell lines discovered in the 1980s confirms their episodic presence but reveals that they tend to be found around both quadrature phases, unlike the pattern in Algol binaries. Phase-dependent variations in the UV N V doublet suggest the presence of a N-enhanced wind from the subdwarf and a possible shock-interaction region between the stars where the subdwarf's wind collides with the disk of the Be star.
Revenue Management with Partially Refundable Fares

We introduce and analyze an intertemporal choice model where customer valuations are uncertain and evolve over time. The model leads directly to the study of call options on capacity that are similar to partially refundable fares. We show that the capacity provider earns significantly higher revenues by selling real options on capacity than on low-to-high pricing. We also investigate the social implications and show that the use of options is both socially optimal and socially efficient.
Chromospheric Ca ii H and K emission among subdwarfs

Echelle spectra have been obtained of the Ca II H and K lines for a sample of metal-poor subdwarf stars as well as for a number of nearby Population I dwarfs selected from among those included in the Mount Wilson HK survey. The main conclusion of this paper is that Ca II H- and K-line emission does occur among subdwarfs. It is particularly notable among those subdwarfs with colours of B−V≥0.75; all such stars observed exhibit chromospheric emission, although emission is observed among some subdwarfs bluer than this colour. The Ca II K emission profile in most subdwarfs exhibits an asymmetry of V/R>1, similar to that seen in the integrated light of the solar disc. Two quantitative indicators of the contrast between the peaks in the emission profile and the neighbouring photospheric line profile are introduced. Measurements of these indicators show that the level of Ca II emission among the subdwarfs is similar to that among low-activity Population I dwarfs.
Three-dimensional acoustic scattering by layered media: a novel surface formulation with operator expansions implementation

The scattering of acoustic waves by irregular structures plays an important role in a wide range of problems of scientific and technological interest. This contribution focuses on the rapid and highly accurate numerical approximation of solutions of Helmholtz equations coupled across irregular periodic interfaces meant to model acoustic waves incident upon a multi-layered medium. We describe not only a novel surface formulation for the problem in terms of boundary integral operators (Dirichlet–Neumann operators), but also a Boundary Perturbation methodology (the Method of Operator Expansions) for its numerical simulation. The method requires only the discretization of the layer interfaces (so that the number of unknowns is an order of magnitude smaller than volumetric approaches), while it avoids not only the need for specialized quadrature rules but also the dense linear systems characteristic of Boundary Integral/Element Methods. The approach is a generalization to multiple layers of Malcolm & Nicholls' Operator Expansions algorithm for dielectric structures with two layers. As with this precursor, this approach is efficient and spectrally accurate.
The behavior of a Costas loop in the presence of space telemetry signals

When the Costas loop is operated in the presence of a residual carrier space telemetry signal, the loop reconstructs its carrier reference from an input signal whose carrier component is not completely suppressed. The telemetry signal investigated in this work is generated by phase shift-keying the data onto a subcarrier and then phase modulating onto the sinusoidal carrier. The telemetry modulation index, telemetry bit rate, subcarrier waveform, and subcarrier frequency are shown to be the key system parameters that contribute to the performance degradation of a Costas loop. Furthermore, the effect of Doppler shift on the loop is also investigated in this work. >
Transition metal catalyzed ring opening reactions of 2-phenyl-3-vinyl substituted 2H-azirines

Abstract Treatment of 2-phenyl-3-vinyl-substituted 2H-azirines with Grubbs' catalyst induces a clean rearrangement and affords products derived from carbon–nitrogen bond cleavage of the 2H-azirine ring. However, when the reaction was carried out using Wilkinson's catalyst in an alcoholic solvent, the only product obtained in high yield corresponded to an α,β-unsaturated oxime.
Dynamical capture of the moon by the earth

The process of extracting the Moon from the Earth through some mechanism of rotational instability, and one that can also set it into orbital motion round the Earth, has nowadays come to be widely recognized as almost certainly dynamically impossible. Accordingly ideas have turned towards the notion that the Moon originated as a separate planet and was later captured by the Earth. It is reasonable to conjecture beforehand that this could happen in a three-body system consisting of the Sun, Earth, and Moon, but nevertheless it is of interest and importance to establish that such a capture is possible within the laws of dynamics, and moreover we should like to have some numerical indications of the initial dimensions that the lunar orbit would have on the basis of such an origin. Dissipative action may well be operative upon the planetary orbits to a minute extent, and there may have been eras in the history of the solar system when such dissipation was greater than average, but it seems certain that the main geometrical features of the process of capture of a satellite must in the final stages be governed purely by dynamical forces arising only from the mutual attractions of the bodies. Thus the first stage towards demonstrating the possibility of capture will be to study motions under purely conservative dynamical forces. Considerations of a phase-space or ergodic nature suggest that if the moon were captured in such a way it would eventually escape again, but we cannot on such a basis form any notion of the period of time for which the body might remain a satellite before escaping again. Actual numerical instances are needed to determine this.
School accountability and teacher mobility

Abstract We exploit a 2002 change in Florida’s school accountability system, and use regression discontinuity and difference-in-difference approaches, to study the effects of accountability pressure on teacher mobility. While school grading “shocks” do not affect mobility at most parts of the measured school quality distribution, there exists strong evidence that teachers are more likely to leave schools that have received a failing grade. Receipt of an “F” grade translates into differently higher turnover for the best teachers, measured by contributions to student test scores, at a school. These results are robust to a wide range of parametric and nonparametric model specifications.
‘To Whom Much Has Been Given...’: Religious Capital and Community Voluntarism Among Churchgoing Protestants

Research on volunteering behavior has consistently found a positive relationship between religion and volunteering. Using a sample of churchgoing Protestants (N=1,738)from the Religious Identity and Influence Survey we examine the specific influences of religiosity, religious identity, religious socialization, and religious social networks on local volunteer activity in church programs and non-church organizations, as well as general volunteering tendencies. These influences are presented within the theoretical framework of religious capital. Logistic regression techniques were applied to determine the strength of the contribution of these influences while accounting for basic background factors. Findings suggest that churchgoing Protestants are influenced by all measures to some degree, but religiosity (specifically participation in church activities) remains the strongest influence. Significant religious influences overall are most pronounced within the context of church-related volunteering which suggests that churchgoing Protestants exhibit a strong sense of community identity through their local churches. A discussion of these results and their implications for volunteering follows.
A Pattern-Driven Security Process for SOA Applications

SOA enables the design of flexible and modular software applications that can be used in a cross- organization context. Unfortunately, those qualities have a negative impact on the security of the software application. In this paper, we investigate the production of secure SOA applications. In particular, we provide an approach to build secure SOA applications that takes into account the new security issues introduced by the complexity of SOA-based applications. We build upon two different approaches to secure SOA applications: model-driven development and the use of security patterns.
Disease persistence in epidemiological models: The interplay between vaccination and migration

We consider the interplay of vaccination and migration rates on disease persistence in epidemiological systems. We show that short-term and long-term migration can inhibit disease persistence. As a result, we show how migration changes how vaccination rates should be chosen to maintain herd immunity. In a system of coupled SIR models, we analyze how disease eradication depends explicitly on vaccine distribution and migration connectivity. The analysis suggests potentially novel vaccination policies that underscore the importance of optimal placement of finite resources.
Cohomological growth rates and Kazhdan-Lusztig polynomials

In a previous work, the authors established various bounds for the dimensions of degree n cohomology and Ext-groups, for irreducible modules of semisimple algebraic groups G (in positive characteristic p) and (Lusztig) quantum groups U ζ (at roots of unity ζ). These bounds depend only on the root system, and not on the characteristic p or the size of the root of unity ζ. This paper investigates the rate of growth of these bounds. Both in the quantum and algebraic group situation, these rates of growth represent new and fundamental invariants attached to the root system ϕ. For quantum groups U ζ with a fixed ϕ, we show the sequence {max L irred dim H n (U ζ , L)} n has polynomial growth independent of ζ. In fact, we provide upper and lower bounds for the polynomial growth rate. Applications of these and related results for $Ext_{U_\zeta }^n $ are given to Kazhdan-Lusztig polynomials. Polynomial growth in the algebraic group case remains an open question, though it is proved that {log max L irred dim H n (G,L)} has polynomial growth ≤ 3 for any fixed prime p (and ≤ 4 if p is allowed to vary with n). We indicate the relevance of these issues to (additional structure for) the constants proposed in the theory of higher cohomology groups for finite simple groups with irreducible coefficients by Guralnick, Kantor, Kassabov and Lubotzky [13].
System size, energy and centrality dependence of strange hadron elliptic flow at STAR

The elliptic flow (v{sub 2}) pattern in terms of hadron mass and transverse momentum p{sub T} is qualitatively described for p{sub T} < 2 GeV/c by ideal hydrodynamics in Au + Au collisions at RHIC. In addition, for p{sub T} = 2-6 GeV/c the measured v{sub 2} follow a universal scaling by the number of quarks explained by quark coalescence/recombination models. These observations suggest that a partonic collectivity develops in the matter in early stage of heavy ion collisions. Centrality as well as system size and energy dependence of the v{sub 2} is important to shed light on the underlying collision dynamics in heavy ion collisions. We present the measurements of centrality dependence of v{sub 2} at {radical}s{sub NN} = 200 and 62.4 GeV in Au + Au and Cu + Cu collisions for K{sub S}{sup 0}, {phi}, {Lambda}, {Xi} and {Omega} at STAR experiment. We focus on the recent Cu + Cu results and discuss the centrality dependence of v{sub 2} as well as the number of quark scaling as a function of transverse kinetic energy at different system size and energies. We also discuss the eccentricity scaled v{sub 2} for identified hadrons and implications that ideal hydrodynamical limit has not been reached at RHIC.
Providing absolute differentiated services for real-time applications in static-priority scheduling networks

In this paper, we propose and analyze a methodology for providing absolute differentiated services for real-time applications. We develop a method that can be used to derive delay bounds without specific information on flow population. With this new method, we are able to successfully employ a utilization-based admission control approach for flow admission. This approach does not require explicit delay computation at admission time and, hence, is scalable to large systems. We assume the underlying network to use static-priority schedulers. We design and analyze several priority assignment algorithms and investigate their ability to achieve higher utilization bounds. Traditionally, schedulers in differentiated services networks assign priorities on a class-by-class basis, with the same priority for each class on each router. In this paper, we show that relaxing this requirement, that is, allowing different routers to assign different priorities to classes, achieves significantly higher utilization bounds.
From physics to economics: An econometric example using maximum relative entropy

Econophysics, is based on the premise that some ideas and methods from physics can be applied to economic situations. We intend to show in this paper how a physics concept such as entropy can be applied to an economic problem. In so doing, we demonstrate how information in the form of observable data and moment constraints are introduced into the method of Maximum relative Entropy (MrE). A general example of updating with data and moments is shown. Two specific econometric examples are solved in detail which can then be used as templates for real world problems. A numerical example is compared to a large deviation solution which illustrates some of the advantages of the MrE method.
A NOTE ON THE INTEGRABILITY OF NON-HERMITIAN EXTENSIONS OF CALOGERO–MOSER–SUTHERLAND MODELS

We consider non-Hermitian but PT-symmetric extensions of Calogero models, which have been proposed by Basu-Mallick and Kundu for two types of Lie algebras. We address the question of whether these extensions are meaningful for all remaining Lie algebras (Coxeter groups) and if in addition one may extend the models beyond the rational case to trigonometric, hyperbolic and elliptic models. We find that all these new models remain integrable, albeit for the non-rational potentials one requires additional terms in the extension in order to compensate for the breaking of integrability.
Temperature and Density Effects on the Local Segmental and Global Chain Dynamics of Poly(oxybutylene)

Dielectric spectroscopy measurements over a broad range of temperature and pressure were carried out on poly(oxybutylene) (POB), a type A polymer (dielectrically active normal mode). There are three dynamic processes appearing at lower frequency: the normal and segmental relaxation modes and a conductivity arising from ionic impurities. In combination with pressure−volume−temperature measurements, the dielectric data were used to assess the respective roles of thermal energy and density in controlling the relaxation times and their variation with T and P. We find that the local segmental and the global relaxation times are both a single function of the product of the temperature times the specific volume, with the latter raised to the power of 2.65. The fact that this scaling exponent is the same for both modes indicates they are governed by the same local friction coefficient, an idea common to most models of polymer dynamics. Nevertheless, near Tg, their temperature dependences diverge. The magnitude o...
Sample-optimal average-case sparse Fourier Transform in two dimensions

We present the first sample-optimal sublinear time algorithms for the sparse Discrete Fourier Transform over a two-dimensional √n × √n grid. Our algorithms are analyzed for the average case signals. For signals whose spectrum is exactly sparse, we present algorithms that use O(k) samples and run in O(k log k) time, where k is the expected sparsity of the signal. For signals whose spectrum is approximately sparse, we have an algorithm that uses O(k log n) samples and runs in O(k log2 n) time, for k = Θ(√n). All presented algorithms match the lower bounds on sample complexity for their respective signal models.
Whatever happened to little Albert

John B. Watson and Rosalie Rayner's 1920 conditioning of the infant Albert B. is a well- known piece of social science folklore. Using pub- lished sources, this article reviews the study's actual procedures and its relationship to Watson's career and work. The article also presents a history of psycholo- gists' accounts of the Albert study, focusing on the study's distortion by Watson himself, general textbook authors, behavior therapists, and most recently, a prominent learning theorist. The author proposes pos- sible causes for these distortions and analyzes the Albert study as an example of myth making in the history of psychology.
Using Terror Alert Levels to Estimate the Effect of Police on Crime

Abstract Changes in the terror alert level set by the Department of Homeland Security provide a shock to police presence in Washington, D.C. Using daily crime data during the period the terror alert system has been in place, we show that the level of crime decreases significantly, both statistically and economically, during high‐alert periods. The decrease in the level of crime is especially large in the National Mall. This provides strong evidence of the causal effect of police on the level of crime and suggests a research strategy that can be used in other cities.
Better Off Than We Know Distorted Perceptions of Incomes and Income Inequality in America

Three studies examined Americans' perceptions of incomes and income inequality using a variety of criterion measures. Contrary to recent findings indicating that Americans underestimate wealth inequality, we found that Americans not only overestimated the rise of income inequality over time, but also underestimated average incomes. Thus, economic conditions in America are more favorable than people seem to realize. Furthermore, ideological differences emerged in two of these studies, such that political liberals overestimated the rise of inequality more than political conservatives. Implications of these findings for public policy debates and ideological disagreements are discussed.
High-dimensional Sparse Inverse Covariance Estimation using Greedy Methods

In this paper we consider the task of estimating the non-zero pattern of the sparse inverse covariance matrix of a zero-mean Gaussian random vector from a set of iid samples. Note that this is also equivalent to recovering the underlying graph structure of a sparse Gaussian Markov Random Field (GMRF). We present two novel greedy approaches to solving this problem. The first estimates the non-zero covariates of the overall inverse covariance matrix using a series of global forward and backward greedy steps. The second estimates the neighborhood of each node in the graph separately, again using greedy forward and backward steps, and combines the intermediate neighborhoods to form an overall estimate. The principal contribution of this paper is a rigorous analysis of the sparsistency of these two greedy procedures, that is, their consistency in recovering the sparsity pattern of the inverse covariance matrix. Surprisingly, we show that both the local and global greedy methods learn the full structure of the model with high probability given just O(d log(p)) samples, which is a significant improvement over state of the art ‘1-regularized Gaussian MLE (Graphical Lasso) that requires O(d 2 log(p)) samples. Moreover, the restricted eigenvalue and smoothness conditions imposed by our greedy methods are much weaker than the strong irrepresentable conditions required by the‘1-regularization based methods. We corroborate our results with extensive simulations and examples, comparing our local and
A convenient method of protecting oxindoles

Abstract The nitrogens of oxindoles and indole were protected by dichloroacetyl group in refluxing DCE. The deprotection of these protected oxindoles and indole has been carried out under basic condition using triethylamine.
An analysis of multiple correlation cancellation loops with a filter in the auxiliary path

A technique known as a "multiple correlation cancellation loop" and also as the "LMS algorithm" is widely used in adaptive arrays for radar, sonar, and communications, as well as in many other signal processing applications. In this paper an analysis of this technique is extended to the case when a linear filter appears in the auxiliary signal path. A general solution to this problem is obtained and several examples for narrow-band and broad-band signals are presented.
Computing Motion Using Resistive Networks

To us, and to other biological organisms, vision seems effortless. We open our eyes and we "see" the world in all its color, brightness, and movement. Yet, we have great difficulties when trying to endow our machines with similar abilities. In this paper we shall describe recent developments in the theory of early vision which lead from the formulation of the motion problem as an ill-posed one to its solution by minimizing certain "cost" functions. These cost or energy functions can be mapped onto simple analog and digital resistive networks. Thus, we shall see how the optical flow can be computed by injecting currents into resistive networks and recording the resulting stationary voltage distribution at each node. These networks can be implemented in cMOS VLSI circuits and represent plausible candidates for biological vision systems.