cssi/SciSciGPT-SciSciNet huggingface dataset:
Optical diffractions as probes to surface diffusion of adsorbates

I review some of the general aspects of using optical diffractions from laser-induced surface density gratings to probe diffusion of adsorbates. Among examples, the recent progress in the study of quantum tunneling diffusions is emphasized.
The Local halo density

For almost 20 years models of the Galaxy have included a dark halo responsible for supporting a substantial fraction of the local rotation velocity and a flat rotation curve at large distances. Estimates of the local halo density range from 2 × 10-25 g cm-3 to 10 × 10-25 g cm-3. By careful modeling of the Galaxy, taking account of the evidence that dark halos are flattened and recent microlensing data, we arrive at a more quantitative estimate, 9.2+ 3.8−3.1 × 10-25 g cm-3. Microlensing toward the LMC indicates that only a small fraction, less than ~30%, can be in the form of MACHOs, which is consistent with the idea that most of the halo consists of cold dark matter particles.
Looking for my self: Identity-driven attention allocation

Abstract This research builds on the motivational aspects of identity salience, finding that social identities direct the allocation of attention in identity-syntonic ways. Drawing from identity-based motivation (Oyserman, 2009; Reed, et al., 2012) we suggest individuals use attention to enhance identity-fit; selectively focusing on cues and stimuli that are identity-consistent. In two studies we find that activating a social identity drives preferential attention toward identity-relevant stimuli. Using a novel paradigm, Study 1 demonstrates that individuals strategically focus attention on identity-consistent emotional stimuli, while also shifting attention away from identity-inconsistent emotional stimuli. Using a dot-probe paradigm, Study 2 extends these results to show that individuals allocate attention toward both emotional and non-emotional (semantic associates) stimuli that are identity-consistent, and away from those that are incompatible. Consistent with theories suggesting cognition and perception are constructed (James, 1890/1983) and that identities direct and influence meaning-making (Oyserman, 2009; Reed et al., 2012), we find that social identities drive attention allocation, with identity-consistent stimuli receiving greater attention; suggesting that an identity’s sense-making begins with motivated attention toward perceiving an identity-consistent environment.
CBWL: a new channel assignment and sharing method for cellular communication systems

A new scheme that allows cell gateways (base stations) to borrow channels from adjacent gateways in a cellular communication system is presented. Borrowed channels are used with reduced transmitted power to limit interference with cochannel cells. No channel locking is needed. The scheme, which can be used with various multiple access techniques, permits simple channel control management without requiring global information about channel usage throughout the system. It provides enhanced traffic performance in homogeneous environments and also can be used to relieve spatially localized traffic overloads (tele-traffic 'hot spots'). Co-channel interference analysis shows that the scheme can maintain the same SIR as nonborrowing schemes. Analytical models using multidimensional birth-death processes and decomposition methods are devised to characterize performance. The results which are also validated by simulation indicate that significantly increased traffic capacity can be achieved in comparison with nonborrowing schemes. >
Yb14MgSb11 and Ca14MgSb11—New Mg-Containing Zintl Compounds and Their Structures, Bonding, and Thermoelectric Properties

Magnesium-containing Zintl phase compounds Yb14MgSb11 and Ca14MgSb11 have been prepared by annealing the mixture of the elements at 1075–1275 K. These compounds are isostructural with the Zintl compound Ca14AlSb11 and crystallize in the tetragonal space group I41/acd (Z = 8). Single-crystal X-ray data (90 K) were refined for Yb14MgSb11 [a = 16.625(9) A, c = 22.24(2) A, V = 6145(8) A3, and R1/wR2 (0.0194/0.0398)] and Ca14MgSb11 [a = 16.693(2) A, c = 22.577(5) A, V = 6291(2) A3, R1/wR2 (0.0394/0.0907)]. This structure type has been shown to be highly versatile with a large number of phases with the general formula A14MPn11 (A = Ca, Sr, Ba, Yb, Eu; M = Mn, Zn, Nb, Cd, Group 13 elements; Pn = Group 15 elements). The two compounds reported in this paper are the first Mg-containing analogs. Replacing M with Mg, which is divalent with no d-orbitals, probes electronic structure and properties of this structure type. Mg2+ is well-known to prefer tetrahedral geometry and allows for integration of the properties of ...
Finite-difference time-domain of HF antennas

The FDTD method with higher-order absorbing boundary conditions is used to model and predict the input impedance and the far-field radiation of electrically short antennas. Far-field radiation results are presented and compared with measurement for HF loop (towel bar) and inverted-L antenna elements used at 10 MHz mounted on a helicopter-like body. Wideband input impedance predictions and measurements are also presented. The computed radiation patterns and input impedance compare well with measurements. >
Finding Intermediates in the O2 Activation Pathways of Non-Heme Iron Oxygenases

Intermediates in the reaction cycle of an oxygenase are usually very informative with respect to the chemical mechanism of O2 activation and insertion. However, detection of these intermediates is often complicated by their short lifetime and the regulatory mechanism of the enzyme designed to ensure specificity. Here, the methods used to detect the intermediates in an extradiol dioxygenase, a Rieske cis-dihydrodiol dioxygenase, and soluble methane monooxygenase are discussed. The methods include the use of alternative, chromophoric substrates, mutagenesis of active site catalytic residues, forced changes in substrate binding order, control of reaction rates using regulatory proteins, and initialization of catalysis in crystallo.
The tendencies in defining an optimum globalization model

Over viewing the most recently evolutions throughout global economy, we can easily conceive that the collateral effects of economical globalization and market integration, represents the main issues debated in specialized professional or political circles. The unanimous impression underlines the fact that integration in contemporary global market development exceeded too much and to profound the conceptual frame formulated as work hypothesis for the beginning of ’80’s the realities evolving radically uncontrolled. In this case, the free capital global running is no longer a factor for market equilibrium as “market fundamentalists” predicted, financial integration as global process creating and forcing gradually the market bubbles in lack of an efficient frame of global supervision. In this context, the international effort should be oriented toward remodeling the fundamental global structures implicated in globalization process.
SUSY-inspired one-dimensional transformation optics

Transformation optics aims to identify artificial materials and structures with desired electromagnetic properties by means of pertinent coordinate transformations. In general, such schemes are meant to appropriately tailor the constitutive parameters of metamaterials in order to control the trajectory of light in two and three dimensions. Here, we introduce a new class of one-dimensional optical transformations that exploits the mathematical framework of supersymmetry (SUSY). This systematic approach can be utilized to synthesize photonic configurations with identical reflection and transmission characteristics, down to the phase, for all incident angles, thus rendering them perfectly indistinguishable to an external observer. Along these lines, low-contrast dielectric arrangements can be designed to fully mimic the behavior of a given high-contrast structure that would have been otherwise beyond the reach of available materials and existing fabrication techniques. Similar strategies can also be adopted to replace negative-permittivity domains, thus averting unwanted optical losses.
Theory of Spin Hall Effects in Semiconductors

Spin Hall effects are a collection of phenomena, resulting from spin-orbit coupling, in which an electrical current flowing through a sample can lead to spin transport in a perpendicular direction and spin accumulation at lateral boundaries. These effects, which do not require an applied magnetic field, can originate in a variety of intrinsic and extrinsic spin-orbit coupling mechanisms and depend on geometry, dimension, impurity scattering, and carrier density of the system—making the analysis of these effects a diverse field of research. In this chapter, we give an overview of the theoretical background of the spin Hall effects and summarize some of the most important results. First, we explain effective spin-orbit Hamiltonians, how they arise from band structure, and how they can be understood from symmetry considerations; including intrinsic coupling due to bulk inversion or structure asymmetry or due to strain, and extrinsic coupling due to impurities. This leads to different mechanisms of spin transport: spin precession, skew scattering, and side jump. Then we present the kinetic (Boltzmann) equations, which describe the spin-dependent distribution function of charge carriers, and the diffusion equation for spin-polarization density. Next, we define the notion of spin currents and discuss their relation to spin polarization. Finally, we explain the electrically induced spin effects; namely, spin polarization and currents in bulk and near boundaries (the focus of most current theoretical research efforts), and spin injection, as well as effects in mesoscopic systems and in edge states. Keywords: spin transport; spin Hall effect; spin accumulation; spin current; intrinsic spin-orbit coupling; extrinsic spin-orbit coupling; skew scattering; side-jump mechanism; semiconductors; graphene
Mitosis recursion for coefficients of Schubert polynomials

Mitosis is a rule introduced by Knutson and Miller for manipulating subsets of the n × n grid. It provides an algorithm that lists the reduced pipe dreams (also known as rc-graphs) of Fomin and Kirillov for a permutation w∈Sn by downward induction on weak Bruhat order, thereby generating the coefficients of Schubert polynomials of Lascoux and Schutzenberger inductively. This note provides a short and purely combinatorial proof of these properties of mitosis.
Multilevel segmentation and integrated bayesian model classification with an application to brain tumor segmentation

We present a new method for automatic segmentation of heterogeneous image data, which is very common in medical image analysis. The main contribution of the paper is a mathematical formulation for incorporating soft model assignments into the calculation of affinities, which are traditionally model free. We integrate the resulting model-aware affinities into the multilevel segmentation by weighted aggregation algorithm. We apply the technique to the task of detecting and segmenting brain tumor and edema in multimodal MR volumes. Our results indicate the benefit of incorporating model-aware affinities into the segmentation process for the difficult case of brain tumor.
Management of Delirium in Terminally Ill AIDS Patients

Delirium is the most common neuropsychiatric complication of hospitalized AIDS patients. Typically, delirium is multifactorial in etiology and a complete evaluation to rule out all treatable, contributable medical conditions should be the first stage in the approach to a delirious AIDS patient. While a search for probable cause is underway, the next goal of treatment should be sedation. To help clinicians recognize and manage delirium in advanced HIV disease, we describe our experience with 206 AIDS patients.
A Catalytic Asymmetric Vinylogous Mukaiyama Aldol Reaction

A vinylogous Mukaiyama aldol reaction, conducted using 10 mol % of a BITIP catalyst and B(OMe)3 as an additive, effects an enantioselective four-carbon chain extension to give versatile E-α,β-unsaturated thiol esters.
Does the Beige Book Move Financial Markets

About two weeks prior to each Federal Open Market Committee (FOMC) meeting, the Federal Reserve releases a description of economic activity in a document called the Beige Book. By creating a quantitative index of these qualitative reports, we examine whether the content of the Beige Book affects asset prices. The results indicate that more positive Beige Book reports on economic growth are associated with increases in interest rates, particularly intermediate- and long-term rates, but not after controlling for several other macroeconomic indicators. The results are consistent with markets viewing the report as a summary indicator of economic growth but not of monetary policy moves in the near term.
Ethnic Diversity and School Funding in Kenya

Author(s): Miguel, Edward A. | Abstract: The impact of ethnic diversity on the provision of local public goods and collective action in Africa remains largely unexplored. To address this gap, this paper explores the relationship between ethnic diversity and local primary school funding in rural western Kenya. The econometric identification strategy relies on the stable, historically determined patterns of ethnic land settlement in western Kenya. The main empirical result is that higher levels of local ethnic diversity is associated with sharply lower primary school funding and worse school facilities in western Kenya. The theory examines school choice and funding decisions when pupil mobility among schools is limited by land market imperfections and ethnic divisions, the relevant case for rural Africa, and predicts that local pupil transfers may lead to upward bias in OLS estimates of the impact of ethnic diversity. This theoretical prediction is confirmed in the data.
Through wall radar imaging using UWB noise waveforms

This paper examines the results of our research on the use of ultra-wideband noise waveforms for imaging objects behind walls. The advantages of using thermally generated noise as a probing signal are introduced. The technique of heterodyne correlation, used to inject coherence in the random noise probing signal and to collapse the wideband reflected signal into a single frequency, is presented. We address issues related to locating, detection, and tracking humans behind walls using the Hilbert-Huang transform approach for human activity characterization. The results indicate that noise radar technology combined with modern signal processing approaches is indeed a viable technique for covert high-resolution imaging of obscured stationary and moving targets.
Hog Producer Preferences for Marketing Contract Attributes

We use a stated preference instrument to elicit producer preferences for the attributes of risk-shifting hog marketing contracts and express acceptable producer trade-offs between contract attributes in a convenient dollar metric. Respondents value an increase in a window contract's price ceiling three to five times more than the same increase in the price floor, which suggests that hog producers dislike contracts that limit up-side price potential (limit positive skewness). The contractor's organizational form is also important. Cooperative forms are preferred by many respondents, particularly those who state that trust in the contractor is an important antecedent for any contractual relationship.
Setting UBVRI Photometric Zero-Points Using Sloan Digital Sky Survey ugriz Magnitudes

We discuss the use of Sloan Digital Sky Survey (SDSS) ugriz point-spread function (PSF) photometry for setting the zero points of UBVRI CCD images. From a comparison with the Landolt (1992) standards and our own photometry we find that there is a fairly abrupt change in B, V, R, & I zero points around g, r, i � 14.5, and in the U zero point at u � 16. These changes correspond to where there is significant interpolation due to saturation in the SDSS PSF fluxes. There also seems to be another, much smaller systematic effect for stars with g, r & 19.5. The latter effect is consistent with a small Malmquist bias. Because of the difficulties with PSF fluxes of brighter stars, we recommend that comparisons of ugriz and UBVRI photometry should only be made for unsaturated stars with g, r and i in the range 14.5 – 19.5, and u in the range 16 – 19.5. We give a prescription for setting the UBV RI zero points for CCD images, and general equations for transforming from ugriz to UBVRI.
Effects of registration regularization and atlas sharpness on segmentation accuracy.

Abstract In non-rigid registration, the tradeoff between warp regularization and image fidelity is typically determined empirically. In atlas-based segmentation, this leads to a probabilistic atlas of arbitrary sharpness: weak regularization results in well-aligned training images and a sharp atlas; strong regularization yields a “blurry” atlas. In this paper, we employ a generative model for the joint registration and segmentation of images. The atlas construction process arises naturally as estimation of the model parameters. This framework allows the computation of unbiased atlases from manually labeled data at various degrees of “sharpness”, as well as the joint registration and segmentation of a novel brain in a consistent manner. We study the effects of the tradeoff of atlas sharpness and warp smoothness in the context of cortical surface parcellation. This is an important question because of the increasingly availability of atlases in public databases, and the development of registration algorithms separate from the atlas construction process. We find that the optimal segmentation (parcellation) corresponds to a unique balance of atlas sharpness and warp regularization, yielding statistically significant improvements over the FreeSurfer parcellation algorithm. Furthermore, we conclude that one can simply use a single atlas computed at an optimal sharpness for the registration–segmentation of a new subject with a pre-determined, fixed, optimal warp constraint. The optimal atlas sharpness and warp smoothness can be determined by probing the segmentation performance on available training data. Our experiments also suggest that segmentation accuracy is tolerant up to a small mismatch between atlas sharpness and warp smoothness.
Tandem Michael Addition/Aldol Reaction of Allenic Ketones with Alkyl Vinyl Ketones: Versatile Synthesis of 2-Alkynyl 1,5-Diketones, 4-Alkynyl-3-hydroxycyclohexanones and 4-Alkynylcyclohexenones

The reactivity of alkynylenolate was investigated in the reactions of allenic ketones and vinyl ketones. We found that different products could be obtained under different conditions. The tetrabutylammonium fluoride (TBAF)-mediated Michael addition of allenic ketones to vinyl ketones gave 2-alkynyl 1,5-diketones as the product. Under stronger basic conditions, a tandem Michael addition/aldol reaction of the two starting materials occurred in one pot, and 4-alkynyl-3-hydroxycyclohexanone could be isolated at low temperature, whereas 4-alkynylcyclohexenones was obtained at room temperature. It should be noted that only one diastereoisomer of 4-alkynyl-3-hydroxycyclohexanone was isolated from the reaction even when ethyl vinyl ketone was used as the Michael acceptor, as determined by 1 H and 13 C NMR spectroscopy. The configurations of the diastereoisomers were confirmed by NOESY spectroscopy.
Serial MSK spread-spectrum multiple-access communications

A serial minimum-shift-keyed (MSK) direct-sequence spread-spectrum multiple-access (DS/SSMA) communication system is described and analyzed to obtain the signal-to-noise ratio. The single-channel system generates the same transmitted signals as a corresponding parallel MSK/DS/SSMA system. Hence, the transmitted signals have a constant envelope and desirable spectral properties. However, hardware is required for only one channel, and the multiple-access capability of the system compares favorably with a standard binary DS/SSMA system. >
Physician Beliefs and Knowledge About Vaccinations Are Cincinnati Doctors Giving Their Best Shot

The purpose of this study was to examine the immunization beliefs and practices of physicians in our community. A two-page descriptive survey of immunization practices and knowledge of vaccine contraindications was sent to all community physicians on the staff of Children's Hospital Medical Center in Cincinnati, Ohio. More than 90% of practitioners used well-child visits for immunization, even if the child was ill. Although 83% of respondents correctly identified illness with fever as a false contraindication to immunization, only 25% (if the child is due for a visit) and 36% (if the child is overdue) would use ill visits to immunize if a child had fever. The chief concern over using ill visits for immunization was that children would not return for regular well visits. We conclude that greater efforts are needed to convince physicians that using ill visits to immunize children will not interfere with routine well care.
Coordinating two serially connected robots for generating large Cartesian velocities

Two serially connected robots in which the base of one robot is held by the end-effector of the other are more capable than a single robot. Serial connection of two robots can enlarge work space and generate large Cartesian force and Cartesian velocities. Two coordination methods are proposed for the robots to generate large Cartesian velocities while avoiding degeneracy. The first method, which is based on a least-energy consumption criterion, decomposes a desired Cartesian velocity into two velocities, one for each robot. Robot joint velocities are then adjusted using a null space approach to avoid degeneracy. The second method includes a degeneracy index in the cost function. As a result, joint velocities are obtained without any further adjustment. For real time applications, computationally simple methods are presented. The results are verified by case studies. >
Simultaneous Airframe and Propulsion Cycle Optimization for Supersonic Aircraft Design

Supersonic aircraft design includes several tradeoffs, each with advantages and disadvantages. The selection of aircraft shape to meet the prescribed requirements is a nontrivial exercise in the case of commercial supersonic configurations with multiple stringent constraints. The number of discrete shape options, along with the detailed aircraft shaping, presents a difficult choice to the configuration designer. Most often, the aircraft shape is frozen, based on experience. In the case of revolutionary shapes or designs, such a choice would be suboptimal. Furthermore, unlike the subsonic designs, the propulsion cycle plays a much more important role than in the earlier stages of design in the case of supersonic configurations. This paper presents an approach for the simultaneous inclusion of airframe and propulsion system parameters in the aircraft design process. The proposed approach parameterizes the geometry in terms of several shape variables and the propulsion system in terms of representative cycle variables. Advanced genetic algorithms are developed and employed to obtain aircraft configurations and propulsion cycle parameters that simultaneously optimize several critical performance metrics including range, sonic boom loudness, and jet velocity. Results from the optimization are presented and design tradeoffs are discussed.
Towards the Total Synthesis of Saponaceolides: Synthesis of cis‐2,4‐Disubstituted 3,3‐Dimethylmethylenecyclohexanes

Controlling diastereoselectivity by metal coordination: In the case of 3,3-dimethylmethylenecyclohexanes 2—a structural unit present in many interesting natural products—the thermodynamically less stable cis-2,4-disubstituted compounds become available through a cyclization event wherein the configuration is determined by a carbopalladation step. Both the cycloisomerization of 1,7-enynes 1 and the intramolecular Heck-type reaction of compounds of type 3 provide the cis product as the major product.
Explicit and implicit targets in open economies

Under a flexible inflation targeting regime, should policymakers avoid any reaction to movements in the foreign exchange market? Using data for six advanced open economies explicitly targeting inflation, this article examines empirically whether real exchange rate disequilibria systematically affect the conduct of monetary policy. Estimates indicate that monetary policy responses in inflation-targeting, open economies have changed significantly, as the institutional framework for the conduct of monetary policy has evolved. In particular, an explicit target for core inflation and a greater use of the expectation channel of monetary policy appear to be the key features of the newest policy framework. In this context, central banks are unlikely to react to regular fluctuations in the exchange rate.
Gridlock’s Gone, Now What?

This article examines the relationship between security returns and “political gridlock,” which occurs when the U.S. House of Representatives, Senate, and presidency are not controlled by the same political party. The findings support the following conclusions: First, the common view that equities prosper during political gridlock is a myth. Second, fixed-income securities do prosper during gridlock. Third, large companies exhibit higher returns than small companies during gridlock. Finally, the relationship between gridlock and security returns is independent of monetary conditions; this finding supports the existence of a unique “gridlock effect.” Overall, political conditions are relevant for investors, but previous views about their influence are misguided.
The progression of chiral anions from concepts to applications in asymmetric catalysis

Novel concepts in asymmetric catalysis have the potential to open up previously inaccessible reaction space. This Review reflects on the origins of an area that has undergone dramatic recent advancement: the use of chiral anions in asymmetric catalysis. Details of a selection of the latest examples are also given.
Estimation of the Return on Capital in Municipal Water Systems

Seventy-fi ve small, municipal water systems are ana- lyzed to determine if they employ the least-cost long-run capital stock, and if they minimize cost given the observed level of capital. The social cost of capital exceeds the estimated return on invest- ment by more than four times, and actual production costs are 36 percent above minimum costs. Median capital stock ineffi ciency, due to overinvestment, is $70,500 per system, and median cost ineffi ciency is $24,300. Extrapolated to the seven thousand similar systems nationwide, the combined cost of these two types of inef- fi ciency is $663.6 million per year.
A Quantile Regression Analysis of Wages in Panama

Differences in the effects of worker characteristics on wages in Panama at different points of the conditional wage distribution are investigated. Public sector employment increases wages relatively more at lower quantiles. Within the public sector, employment in that sector increases wages of the median worker and reduces wage inequality. Presence of a labor union increases relatively more private sector wages at lower quantiles. Unions reduce wage inequality within the union private sector and increase average wages within that sector. In the public sector, the presence of a labor union increases wages of men at lower quantiles at a lower rate than in the private sector. Self-employment decreases wages at lower quantiles and increases wages at higher quantiles. Urban location affects wages in a U-shaped pattern as one moves from lower to higher quantiles. Rates of return to experience are higher for men at higher quantiles. Experience increases men's wage inequality.
Measurement and Prediction of the Effects of Nonuniform Surface Roughness on Turbulent Flow Friction Coefficients

Revue des methodes de prevision des coefficients de frottement dans des ecoulements turbulents. Presentation de donnees experimentales sur le coefficient de frottement dans des ecoulements en conduite pour des nombres de Reynolds de 10000 a 600000, pour deux sortes de surfaces rugueuses
Fluid Structure Interactions for Blast Wave Mitigation

Abstract : The dynamic response of a free-standing plate subjected to a blast wave is studied numerically to investigate the effects of fluid-structure interaction (FSI) in blast wave mitigation. Previous work on the FSI between a blast wave and a free-standing plate (Kambouchev, N., et al., 2006, Nonlinear Compressibility Effects in Fluid-Structure Interaction and Their Implications on the Air-Blast Loading of Structures, J. Appl. Phys., 100(6), p. 063519) has assumed a constant atmospheric pressure at the back of the plate and neglected the resistance caused by the shock wave formation due to the receding motion of the plate. This paper develops an FSI model that includes the resistance caused by the shock wave formation at the back of the plate. The numerical results show that the resistance to the plate motion is especially pronounced for a light plate, and as a result, the previous work overpredicts the mitigation effects of FSI. Therefore, the effects of the interaction between the plate and the shock wave formation at the back of the plate should be considered in blast wave mitigation.
Blind detection of multirate asynchronous CDMA signals in multipath channels

Blind detection of a desired user's signal in a multirate direct sequence code division multiple access (DS-CDMA) system [using either variable sequence length (VSL) or multicode (MC) access] is considered. A code-constrained inverse filter criterion (IFC)-based blind detector for equal-rate CDMA signals to detect a desired user's signal was presented by Tugnait and Li (2001). The IFC method exploits the higher order statistics of the data. In multirate CDMA systems, a high-rate user signal may be treated as the superposition of several virtual basic-rate signals. The code-constrained IFC-based detector may be used to detect a given basic-rate virtual signal. This, however, does not solve the problem of combining the detected virtual basic-rate signals to yield the original high-rate signal since the former may be delayed by different equalization delays, may be multiply extracted, and may be in different "order." In this paper, novel approaches combining the code-constrained IFC and a penalty function are developed to cope with this problem for VSL and MC multirate access methods. Global minima of the proposed cost functions are analyzed. Three illustrative simulation examples are presented, including an example where the proposed algorithms are compared with an existing subspace approach (and its modifications), a clairvoyant matched filter receiver, and a known channel linear minimum mean-square error (MMSE) receiver.
On the rank of random sparse matrices

We investigate the rank of random (symmetric) sparse matrices. Our main finding is that with high probability, any dependency that occurs in such a matrix is formed by a set of few rows that contains an overwhelming number of zeros. This allows us to obtain an exact estimate for the co-rank.
Endovascular intervention for pelvic congestion syndrome is justified for chronic pelvic pain relief and patient satisfaction.

Objective Pelvic congestion syndrome (PCS) is difficult to diagnose, poorly understood, and often confused with other causes of chronic pelvic pain. Thus, gonadal vein reflux, its relation to lower extremity venous insufficiency (LEVI), and treatment remains controversial to physicians and payors. We present our experience with endovascular PCS treatment and hypothesize that properly selected patients can realize significant improvement. Methods A retrospective study of patients treated for PCS at our institution from 2008 to 2012 was performed. Diagnosis was made clinically by the presence of pelvic pain, dyspareunia, and/or perineal varicosities. Clinical parameters, procedural details, and follow-up were reviewed. A questionnaire including a visual analog scale was sent to patients. Results Diagnosis was made in 15 women (mean age, 36 years; mean parity, two). All had pelvic pain, 6 had dyspareunia, 14 had perineal varicosities, and 10 had concomitant LEVI. Fourteen had gonadal vein reflux (mean diameter, 7.4 mm) and pelvic varicosities at angiography and had coiling (n = 12) and/or Amplatzer plug (St. Jude Medical, Inc, St. Paul, Minn) (n = 4). One patient had stenting of a stenotic left common iliac vein. All patients with concomitant LEVI had successful appropriate treatment. Eight patients completed the questionnaire at a mean follow-up of 4 years. The mean pelvic pain score went from 9.375 to 1.875 post-procedure (P Conclusions Endovascular PCS treatment offers excellent pelvic pain relief and patient satisfaction. Women with pelvic pain, dyspareunia, or perineal varicosities with gonadal vein reflux and pelvic varicosities or iliac vein stenosis should not be denied treatment. A significant number may have concomitant LEVI and should be screened accordingly.
Redshift Evolution of the Nonlinear Two-Point Correlation Function

This paper presents a detailed theoretical study of the two-point correlation function ξ for both dark matter halos and the matter density field in five cosmological models with varying matter density Ωm and neutrino fraction Ων. The objectives of this systematic study are to evaluate the nonlinear gravitational effects on ξ, to contrast the behavior of ξ for halos versus matter, and to quantify the redshift evolution of ξ and its dependence on cosmological parameters. Overall, ξ for halos exhibits markedly slower evolution than ξ for matter, and its redshift dependence is much more intricate than the single power-law parameterization used in the literature. Of particular interest is that the redshift evolution of the halo-halo correlation length r0 depends strongly on Ωm and Ων, being slower in models with lower Ωm or higher Ων. Measurements of ξ to higher redshifts can therefore be a potential discriminator of cosmological parameters. The evolution rate of r0 for halos within a given model increases with time, passing the phase of fixed comoving clustering at z~1-3 toward the regime of stable clustering at z~0. The shape of the halo-halo ξ, on the other hand, is well approximated by a power law with slope -1.8 in all models and is not a sensitive model discriminator.
A Mechanism of Combustion Instability in Lean Premixed Gas Turbine Combustors

There has been increased demand in recent years for gas turbines that operate in a lean, premixed (LP) mode of combustion in an effort to meet stringent emissions goals. Unfortunately, detrimental combustion instabilities are often excited within the combustor when it operates under lean conditions, degrading performance and reducing combustor life. To eliminate the onset of these instabilities and develop effective approaches for their control, the mechanisms responsible for their occurrence must be understood. This paper describes the results of an investigation of the mechanisms responsible for these instabilities. These studies found that combustors operating in a LP mode of combustion are highly sensitive to variations in the equivalence ratio (O) of the mixture that enters the combustor. Furthermore, it was found that such O variations can be induced by interactions of the pressure and flow oscillations with the reactant supply rates. The O perturbations formed in the inlet duct (near the fuel injector) are convected by the mean flow to the combustor where they produce large amplitude heat release oscillations that drive combustor pressure oscillations. It is shown that the dominant characteristic time associated with this mechanism is the convective time from the point of formation of the reactive mixture at the fuel injector to the point where it is consumed at the flame. Instabilities occur when the ratio of this convective time and the period of the oscillations equals a specific constant, whose magnitude depends upon the combustor design, Significantly, these predictions are in good agreement with available experimental data, strongly suggesting that the proposed mechanism properly accounts for the essential physics of the problem. The predictions of this study also indicate, however, that simple design changes (i.e., passive control approaches) may not, in general, provide a viable means for controlling these instabilities, due to the multiple number of modes that may be excited by the combustion process.
CURRENCY INCONVERTIBILITY, PORTFOLIO BALANCE AND RELATIVE PRICES

Abstract This paper analyzes regimes of currency inconvertibility in the framework of a simple general equilibrium model where exports and imports are either officially traded or smuggled and where a non-traded good is also produced and consumed. Residents allocate financial wealth between domestic currency and “black” market foreign exchange. It is shown that stability requires the effect of relative prices on the demand for goods to dominate their effect on the demand for assets. A once-and-for-all devaluation of the official exchange rate does not change the currency composition of private financial wealth, but a constant rate of change of the official rate (the crawling peg) does. The direction of the effect of monetary policy on the currency ratio depends on the nature of expectations about relative asset returns. If expectations are “rational” or “hyperopic”, an increase in the rate of crawl increase the return on foreign currency and hence the currency substitution ratio whereas, if expectations are static, it may reduce it.
1381 and the Malthus Delusion

What were income trends before the Industrial Revolution? Clark (2007b) argued both theoretically and empirically that pre-industrial income fluctuated, but was not trending upwards, a position Persson (2008) labeled “the Malthus Delusion.” Clark (2010a), in particular, estimated that pre-industrial English income was as high on average as in 1800. In contrast, Broadberry et al. (2011) estimate that income tripled between 1270 and 1800. One test of early income estimates is the share employed in farming. This paper, focusing on the poll tax returns of 1379–1381, shows that only 56–59% of the English population was in farming or fishing. This small share implies incomes in 1381 equivalent to those of 1800.
Verifiable distributed oblivious transfer and mobile agent security

The mobile agent is a fundamental building block of the mobile computing paradigm. In mobile agent security, oblivious transfer (OT) from a trusted party can be used to protect the agent's privacy and the hosts' privacy. In this paper, we introduce a new cryptographic primitive called Verifiable Distributed Oblivious Transfer (VDOT), which allows us to replace a single trusted party with a group of threshold trusted servers. The design of VDOT uses a novel technique called consistency verification of encrypted secret shares. VDOT protects the privacy of both the sender and the receiver against malicious attacks of the servers. We also show the design of a system to apply VDOT to protect the privacy of mobile agents. Our design partitions an agent into the general portion and the security-sensitive portion. We also implement the key components of our system. As far as we know, this is the first effort to implement a system that protects the privacy of mobile agents. Our preliminary evaluation shows that protecting mobile agents not only is possible, but also can be implemented efficiently.
Optimization of high-order harmonic generation by genetic algorithm and wavelet time-frequency analysis of quantum dipole emission

We present an ab initio three-dimensional quantum study of the coherent control of high-order harmonic generation ~HHG! processes in intense pulsed laser fields by means of the genetic algorithm optimization of the laser-pulse amplitude and phase. Accurate time-dependent wavefunction and HHG power spectrum are obtained by the time-dependent generalized pseudospectral method and wavelet transform is used to obtain the dynamical phase associated with the dipole-emission time profile. It is shown that ‘‘intra-atomic’’ dynamical phase matching on the sub-optical cycle, attosecond, time scale can be achieved, leading to nearly perfect constructive interference between different returning electronic wave packets and marked improvement in both emission intensity and purity of a given harmonic order. The study of coherent control of atomic and molecular processes is a subject of much current interest in science and technology @1#. In particular, temporally shaped ultrashort laser pulses have been successfully used to design welldefined wave packets@2#, and to control multiphoton absorption @3# and chemical reactions @4#, etc. In the area of the interaction of atoms with intense-laser-pulse, high-order harmonic generation ~HHG! of orders as high as 300 has been observed @5,6#, with photon energies in excess of 500 eV. A novel concept of ‘‘intra-atomic’’ phase matching has been recently introduced, allowing the enhancement of the intensity of a specific high harmonic @7#. It is shown that by carefully tailoring the shape of the temporal profile of the driving laser pulse, one can control the time evolution of the electron response to the intense laser field on a sub-opticalcycle, attosecond time scale @7#. A semiclassical model @8,9# is used to interpret these results in terms of the constructive interference in the frequency domain between different electron trajectories @10#, but the effect of atomic structure is not considered. In this Rapid Communication, we present a fully ab initio quantum treatment of the coherent control and enhancement of high-harmonic emission by means of the genetic algorithm ~GA! optimization @11# of the laser-pulse shape and intra-atomic phase matching. We show that by combining the GA search algorithm and accurate quantum solution of the
A bilinear programming approach for multiagent planning

Multiagent planning and coordination problems are common and known to be computationally hard. We show that a wide range of two-agent problems can be formulated as bilinear programs. We present a successive approximation algorithm that significantly outperforms the coverage set algorithm, which is the state-of-the-art method for this class of multiagent problems. Because the algorithm is formulated for bilinear programs, it is more general and simpler to implement. The new algorithm can be terminated at any time and-unlike the coverage set algorithm-it facilitates the derivation of a useful online performance bound. It is also much more efficient, on average reducing the computation time of the optimal solution by about four orders of magnitude. Finally, we introduce an automatic dimensionality reduction method that improves the effectiveness of the algorithm, extending its applicability to new domains and providing a new way to analyze a subclass of bilinear programs.
The Impact of Health Insurance on Health

How does health insurance affect health? After reviewing the evidence on this question, we reach three conclusions. First, many of the studies claiming to show a causal effect of health insurance on health do not do so convincingly because the observed correlation between insurance and good health may be driven by other, unobservable factors. Second, convincing evidence demonstrates that health insurance can improve health measures of some population subgroups, some of which, although not all, are the same subgroups that would be the likely targets of coverage expansion policies. Third, for policy purposes we need to know whether the results of these studies generalize. Solid answers to the multitude of important questions about how specific health insurance policy options may affect health seem likely to be forthcoming only with investment of substantial resources in social experiments.
Development of an ultra-wideband radar system for vehicle detection at railway crossings

This paper describes an ultra-wideband (UWB) radar system designed to detect motor vehicles such as cars and trucks when they are present at a railway crossing. Once fully developed, the detection performance of the system is to be compared against a video detection system in a test at a crossing in Maywood, Illinois. If the test is successful this system may be further developed and installed at a four-quadrant gate crossing to sense vehicles trapped at the crossing island (i.e. the area bounded by the gate arms). This paper describes the problem at hand and gives details of the radar system development to date. With the current prototype, a pulse width of 3 ns has been achieved, which yields adequate range resolution for this application.
Approximate inverse frequent itemset mining: privacy, complexity, and approximation

In order to generate synthetic basket datasets for better benchmark testing, it is important to integrate characteristics from real-life databases into the synthetic basket datasets. The characteristics that could be used for this purpose include the frequent itemsets and association rules. The problem of generating synthetic basket datasets from frequent itemsets is generally referred to as inverse frequent itemset mining. In this paper, we show that the problem of approximate inverse frequent itemset mining is NP-complete. Then we propose and analyze an approximate algorithm for approximate inverse frequent itemset mining, and discuss privacy issues related to the synthetic basket dataset. In particular, we propose an approximate algorithm to determine the privacy leakage in a synthetic basket dataset.
Parallelizing while loops for multiprocessor systems

Current parallelizing compilers treat while loops and do loops with conditional exits as sequential constructs because their iteration space is unknown. Because these types of loops arise frequently in practice, we have developed techniques that can automatically transform them for parallel execution. We succeed in parallelizing loops involving linked lists traversals-something that has not been done before. This is an important problem since linked list traversals arise frequently in loops with irregular access patterns, such as sparse matrix computations. The methods can even be applied to loops whose data dependence relations cannot be analyzed at compile-time. Experimental results on loops from the PERFECT Benchmarks and sparse matrix packages show that these techniques can yield significant speedups. >
Astronomy and astrophysics with gravitational waves in the advanced detector era

With the advanced gravitational wave detectors coming on line in the next 5 years, we expect to make the first detections of gravitational waves from astrophysical sources, and study the properties of the waves themselves as tests of general relativity. In addition, these gravitational waves will be powerful tools for the study of their astrophysical sources and source populations. They carry information that is quite complementary to what can be learned from electromagnetic or neutrino observations, probing the central gravitational engines that power the electromagnetic emissions at the outer layers of the source. Preparations are being made to enable near-simultaneous observations of both gravitational wave and electromagnetic observations of transient sources, using low-latency search pipelines and rapid sky localization. We will review the many opportunities for multi-messenger astronomy and astrophysics with gravitational waves enabled by the advanced detectors, and the preparations that are being made to quickly and fully exploit them.