cssi/SciSciGPT-SciSciNet huggingface dataset:
Do Banks Provide Financial Slack

We study the decision to choose bank debt rather than public securities in a firm's marginal financing choice. Using a sample of 500 firms over the 1980 to 1993 time period, we find that firms are relatively more likely to choose bank loans when variables that measure asymmetric information problems are elevated. The sensitivity of the likelihood of choosing bank debt to information problems is greater for firms with no public debt outstanding. These results are consistent with the hypothesis that banks help alleviate asymmetric information problems and that firms weigh these information benefits against a wide range of contracting costs when choosing bank financing. WHY DO SOME FIRMS BORROW from public sources while others rely exclusively on private lenders? The answer to this question is not well understood. Existing theories suggest that a firm must consider the tradeoff between the benefits and costs of bank debt financing relative to other potential financing choices. The potential benefits of bank financing include low moral hazard and adverse selection costs and ease of renegotiation in financial distress.1 The potential costs of bank financing include monitoring costs, suboptimal liquidation outcomes, and distortions induced by information monopolies.2 The goal of this paper is to identify whether adverse selection problems influence a firm's choice between new bank debt, public debt, or common stock. In particular, we are interested in assessing the empirical validity of the hypothesis that banks have the ability to accurately price a firm's claims, thus inducing a preference for firms that are undervalued by the market to
Stereoretentive Halogenations and Azidations with Titanium(IV) Enabled by Chelating Leaving Groups

DedicatedtoProfessorLuigiMandoliniontheoccasionofhis65thbirthdayStereospecific functional group conversions of nonracemicalcohols and diols and their derivatives are of increasingimportance given the powerful catalytic asymmetric reactionsavailable for their synthesis. If neighboring-group participa-tion
Robust detection and identification of sparse segments in ultrahigh dimensional data analysis

Copy number variants (CNVs) are alternations of DNA of a genome that results in the cell having a less or more than two copies of segments of the DNA. CNVs correspond to relatively large regions of the genome, ranging from about one kilobase to several megabases, that are deleted or duplicated. Motivated by CNV analysis based on next generation sequencing data, we consider the problem of detecting and identifying sparse short segments hidden in a long linear sequence of data with an unspecified noise distribution. We propose a computationally efficient method that provides a robust and near-optimal solution for segment identification over a wide range of noise distributions. We theoretically quantify the conditions for detecting the segment signals and show that the method near-optimally estimates the signal segments whenever it is possible to detect their existence. Simulation studies are carried out to demonstrate the efficiency of the method under different noise distributions. We present results from a CNV analysis of a HapMap Yoruban sample to further illustrate the theory and the methods.
Natural Resources, Neither Curse nor Destiny

This volume studies the role of natural resources in development and economic diversification. It brings together a variety of analytical perspectives, ranging from econometric analyses of economic growth to historical studies of successful development experiences in countries with abundant natural resources. This book addresses two key questions for policy makers in natural resource-rich regions such as Latin America: First, is natural resource wealth an asset or a liability for development and, if potentially the former, how can its contribution be enhanced? And second, can countries rich in natural resources efficiently diversify toward manufacturing or service-sector exports?
OBSERVABILITY OF SCATTERED-LIGHT ECHOES AROUND VARIABLE STARS AND CATACLYSMIC EVENTS

Scattered-light echoes from variable and cataclysmic stars offer one of the most effective means to probe the structure and composition of circumstellar and interstellar media. I build a simple model of light-echo surface brightness by considering the source spectrum and the dust density, geometry, and scattering efficiency. I use this model to investigate whether echoes should be observable around short and long-period giants, cataclysmic variables, and supernovae. Only supernovae are expected to illuminate material on both circumstellar and interstellar scales. Giant and post-AGB stars (e.g., Cepheids and Miras) with high mass-loss rates can produce observable echoes within their circumstellar envelopes. Echoes from novae and dwarf novae are probably detectable only from nearby material, and only in unusually dense gas. I present characteristic exposure times to image such echoes over a wide range of wavelengths for ground-based and Hubble Space Telescope observations. I apply these results to analyze the dust properties of the recently reported echoes around SN 1993J, finding the dust in M81 to have a grain-size distribution and chemical composition consistent with Galactic dust. Optimal observing strategies for echo detection are also discussed.
Dark Matter, a Challenge for Particle Astrophysics

There is mounting evidence that at least 90% of the mass in the universe is “dark.” By dark we mean that it is does not emit nor absorb any kind of electromagnetic radiation and is only seen by its gravitational effect on visible objects. We do not yet know the exact amount, nor the nature, of this obviously major component of the physical universe. This fundamental puzzle constitutes the “dark matter problem” which dates back to Zwicky,1 and has been often reviewed in the past2. Its solution touches central issues in cosmology and astrophysics, and probably also involves particle physics.
Is What’s Bad for the Goose (Tenant), Bad for the Gander (Landlord): A Retail Real Estate Perspective

We explore the economic dependence and financial market feedback effects among firms with economic linkages, notably landlord-tenant when shocks occur to the system. In particular, we examine 157 m...
A Discrete Model of the Inverse Love Wave Problem

A mathematical model is used in order to understand some unresolved aspects of the uniqueness of the inverse problem for the Earth normal modes. More specifically, the conjecture of Backus & Gilbert regarding the information content of the natural frequencies of modes associated with different angular numbers is examined. This is done for the geophysically artificial case of a vibrating system which is a discrete version of an elastic membrane in the shape of an infinite strip, with a density variation across the width. The question then becomes whether the dispersion relations for the waves propagating along this membrane are sufficient to determine the density uniquely. A definitive answer to this conjecture is still not available, but our results strengthen its validity.
2001 Mars Odyssey orbit determination during interplanetary cruise

On 24 October 2001 coordinated universal time, following a seven-month journey to Mars, Odyssey executed a nominal orbit insertion burn to be captured successfully into orbit around Mars. The excellent navigation performance during the interplanetary cruise resulted in arrival conditions over the north pole of Mars well within 1‐σ of the designed values. The achieved altitude above the north pole was less than 1 km away from the 300-km target altitude. Several sources of error made the orbit determination process for Odyssey challenging. The largest of these errors was caused by the periodic autonomous angular momentum desaturation events. Several navigational aids were brought forth to mitigate the error sources and improve the accuracy of Odyssey’s interplanetary cruise navigation. The most significant of these included the incorporation of very long baseline interferometry, delta-differential one-way range tracking data into the orbit determination filtering process and the placement of the spacecraft into a low-torque attitude during the final two months of interplanetary cruise. Orbit determination solution consistency was routinely evaluated through a battery of filter strategies and data combinations. The orbit determination processes and results of Mars Odyssey from launch to orbit insertion at Mars are discussed.
On cycling in the simplex method of the transportation problem

This paper shows that cycling of the simplex method for the m×n Transportation Problem where k-1 zero basic variables are leaving and reentering the basis does not occur once it does not occur in the k×k Assignment Problem. A method to disprove cycling for a particular k is applied for k=2,3,34,5 and 6.
Administrative Law Judges in Fair Housing Enforcement: Attitudes, Case Facts, and Political Control ∗

Objective. This study investigates the effect of attitudes, case facts, and political control on the fair housing decisions made by administrative law judges (ALJs) at the Department of Housing and Urban Development (HUD). Methods. Based on data obtained from HUD under a Freedom of Information Act request, we use Probit regression to model the outcomes of every housing discrimination case decided by the entire population of ALJs between 1989 and 2003. Results. We discover significant variation in the likelihood of a pro-complainant outcome and the amount of actual damages awarded in fair housing disputes. Conclusion. The attitudinal model of judicial decision making appears to apply to ALJ behavior in housing discrimination cases. At the same time, case facts, bureaucratic oversight, and other legal factors constrain ALJs. Researchers have long been interested in why judges decide cases the way they do (Segal and Spaeth, 2002), but the vast majority of these studies have focused on the decisions of judges acting in a purely judicial capacity in cases before the federal and state courts, rather than in a quasi-bureaucratic capacity (Baum, 2011). This article draws on the literature exploring the influence of attitudes and case facts on judicial decision making in order to test those findings in a quite different context from that in which they are usually investigated—the decisions of federal administrative law judges (ALJs). We test both attitudinal and fact-based determinants, along with any bureaucratic effects, of judicial behavior in ALJ decisions in housing discrimination cases at the U.S. Department of Housing and Urban Development (HUD). Although ALJs are similar to other federal judges in their role as adjudicators, they differ significantly from other federal judges in terms of their method of selection. Although Article III judges are political appointees who
Knowledge Content and Worker Participation in Environmental Management at NUMMI

 This paper looks at, within the context of lean production, how and in what ways employees participate in environmental improvements. The paper uses data from an automobile plant well known for its participative work structures, New United Motor Manufacturing (NUMMI), to look more closely at the dynamics of worker participation in environmental management (i.e. management of pollution and waste). Findings show that while workers possess important contextual knowledge, the importance of process, intra-organizational and external knowledge make the role of specialist staff (both internal and external to the environmental function) critically important for environmental improvements. Additionally, environmental improvements often required a combination of more than one knowledge type. The paper discusses how the culture and management structure at NUMMI and other lean plants encourage this combination. Implications for environmental management, lean production, and future research on worker participation are discussed.
Winning the Colonoscopy Revaluation Delay

© 2015 by the AGA Institute 1542-3565/$36.00 http://dx.doi.org/10.1016/j.cgh.2015.01.007 Over recent years, we have warned American Gastroenterological Association (AGA) members that physician reimbursement is in turbulent times. While this remains the case, we scored a point for fairness and transparency in the 2015 Medicare Physician Fee Schedule Final Rule. The AGA Governing Board asked reimbursement expert Dr Dawn Francis to reflect on policy issues in the 2015 rule and outline the challenges we face in the future.
Consumption, house prices, and collateral constraints: a structural econometric analysis

If borrowing capacity of indebted households is tied to the value of their home, house prices should enter a correctly specified aggregate Euler equation for consumption. I develop a simple two-agent, dynamic general equilibrium model in which home (collateral) values affect debt capacity and consumption possibilities for a fraction of the households. I then derive and estimate an aggregate consumption Euler equation, and estimate its structural parameters. The results provide robust support for housing prices as a driving force of consumption fluctuations.
Inductive Teaching and Learning Methods: Definitions, Comparisons, and Research Bases

Traditional engineering instruction is deductive, beginning with theories and progressing to the applications of those theories. Alternative teaching approaches are more inductive. Topics are introduced by presenting specific observations, case studies or problems, and theories are taught or the students are helped to discover them only after the need to know them has been established. This study reviews several of the most commonly used inductive teaching methods, including inquiry learning, problem-based learning, project-based learning, case-based teaching, discovery learning, and just-in-time teaching. The paper defines each method, highlights commonalities and specific differences, and reviews research on the effectiveness of the methods. While the strength of the evidence varies from one method to another, inductive methods are consistently found to be at least equal to, and in general more effective than, traditional deductive methods for achieving a broad range of learning outcomes.
International comparisons of productivity growth: the role of information technology and regulatory practices

Abstract While information technology (IT) is credited with the recent acceleration in productivity in the United States, many other industrial countries have not experienced a pickup in productivity growth. To explain this productivity divergence, we use panel data from 1992 to 1999 for 13 industrial countries and find that this divergence is driven in part by differences in both the production and adoption of information technologies. Based on this finding, we proceed to investigate what factors might play a role in explaining differences in IT adoption. Our results support the view that burdensome regulatory environments and, in particular, regulations affecting labour market practices have impeded the adoption of information technologies and have slowed productivity growth in a number of industrial countries.
Efficient CT simulation of the four-field technique for conformal radiotherapy of prostate carcinoma

PURPOSE: Conformal radiotherapy of prostate carcinoma relies on contouring of individual CT slices for target and normal tissue localization. This process can be very time consuming. In the present report, we describe a method to more efficiently localize pelvic anatomy directly from digital reconstructed radiographs (DRRs). MATERIALS AND METHODS: Ten patients with prostate carcinoma underwent CT simulation (the spiral mode at 3 mm separation) for conformal four-field "box" radiotherapy. The bulbous urethra and bladder were opacified with iodinated contrast media. On lateral and anteroposterior DRRs, the volume of interest (VOI) was restricted to 1.0-1.5 cm tissue thickness to optimize digital radiograph reconstruction of the prostate and seminal vesicles. By removing unessential voxel elements, this method provided direct visualization of those structures. For comparison, the targets of each patient were also obtained by contouring CT axial slices. RESULTS: The method was successfully performed if the target structures were readily visualized and geometrically corresponded to those generated by contouring axial images. The targets in 9 of 10 patients were reliable representations of the CT-contoured volumes. One patient had 18 mm variation due to the lack of bladder opacification. Using VOIs to generate thin tissue DRRs, the time required for target and normal tissue localization was on the average less than 5 min. CONCLUSION: In CT simulation of the four-field irradiation technique for prostate carcinoma, thin-tissue DRRs allowed for efficient and accurate target localization without requiring individual axial image contouring. This method may facilitate positioning of the beam isocenter and provide reliable conformal radiotherapy.
The more plot: displaying measures of risk & error from simulation output

The focus on mean (long-run average) performance as the primary output measure produced by simulation experiments diminishes the usefulness of simulation for characterizing risk. Confidence intervals on means are often misinterpreted as measures of future risk, when in fact they are measures of error. We introduce the measure of risk & error (MORE) plot as a way to display and make intuitive the concepts of risk and error and thus support sound experiment design and correct decision making.
Bell's Law for the Birth and Death of Computer Classes: A theory of the Computer's Evolution

In 1951 a man could walk inside a computer. By 2010, a computer cluster with millions of processors will have expanded to building size. In this new paper Gordon Bell explains the history of the computing industry, positing a general theory ("Bell's Law) for the creation, evolution, and death of computer classes since 1951. Using the exponential transistor density increases forecast by Moore's Law in 1965 and 1975 as the principal basis for the life cycle of computer classes after the microprocessor was introduced in 1971, he predicts that the powerful microprocessor will be the basis for nearly all computer classes in 2010, from personal computers and servers costing a few thousand dollars to scalable servers costing a few hundred million dollars. Soon afterward, billions of cell phones for personal computing, and tens of billions of wireless sensor nets will unwire and interconnect everything.
Bayesian Watermark Attacks

This paper presents an application of statistical machine learning to the field of watermarking. We propose a new attack model on additive spread-spectrum watermarking systems. The proposed attack is based on Bayesian statistics. We consider the scenario in which a watermark signal is repeatedly embedded in specific, possibly chosen based on a secret message bitstream, segments (signals) of the host data. The host signal can represent a patch of pixels from an image or a video frame. We propose a probabilistic model that infers the embedded message bitstream and watermark signal, directly from the watermarked data, without access to the decoder. We develop an efficient Markov chain Monte Carlo sampler for updating the model parameters from their conjugate full conditional posteriors. We also provide a variational Bayesian solution, which further increases the convergence speed of the algorithm. Experiments with synthetic and real image signals demonstrate that the attack model is able to correctly infer a large part of the message bitstream and obtain a very accurate estimate of the watermark signal.
Migration-proof Tiebout equilibrium: existence and asymptotic efficiency

Abstract Tiebout’s basic claim was that when public goods are local, competition between jurisdictions solves the free riding problem in the sense that equilibria exist and are always Pareto efficient. Unfortunately, the literature does not quite support this conjecture. For finite economies, one must choose between notions of Tiebout equilibrium which are Pareto optimal but which may be empty, or which are nonempty but may be inefficient. This paper introduces a new equilibrium notion called migration-proof Tiebout equilibrium which we argue is a natural refinement of Nash equilibrium for a multijurisdictional environment. We show for sufficiently large economies with homogeneous consumers, such an equilibrium always exists, is unique, and is asymptotically Pareto efficient.
Propagation of Internal Gravity Waves in a Thermally Stratified Atmosphere

The reflection of internal gravity waves in a thermally stratified atmosphere may result in the formation of a wave duct between a strongly reflecting region and the ground. In some cases total reflection occurs and wave energy propagates horizontally in the duct without loss. In other cases, however, the reflection is not total but is nevertheless strong; in these latter cases the duct is ‘imperfect,’ and wave energy is carried to great distances with only minor loss in the form of a leakage into the overlying regions. In this paper the imperfect ducting of internal gravity waves in thermally stratified atmospheres is analyzed numerically, temperature profiles generally representative of summer and winter conditions being studied in detail. Modal solutions relating the frequencies, wavelengths, propagation speeds, and attenuation indices to one another are obtained. An evaluation of the role in the ducting process of the atmospheric temperature profile is made using computed patterns of energy flow and vertical distributions of energy density. The results show the existence of propagation modes which are strongly ducted by the atmosphere and which have properties that are in general agreement with traveling ionospheric disturbances in the F region.
Estimation with Norm Regularization

Analysis of non-asymptotic estimation error and structured statistical recovery based on norm regularized regression, such as Lasso, needs to consider four aspects: the norm, the loss function, the design matrix, and the noise model. This paper presents generalizations of such estimation error analysis on all four aspects. We characterize the restricted error set, establish relations between error sets for the constrained and regularized problems, and present an estimation error bound applicable to any norm. Precise characterizations of the bound is presented for a variety of noise models, design matrices, including sub-Gaussian, anisotropic, and dependent samples, and loss functions, including least squares and generalized linear models. Gaussian width, a geometric measure of size of sets, and associated tools play a key role in our generalized analysis.
A fast method of numerical quadrature for p-version finite element matrices

A new technique of numerical quadrature especially suited for quadrilateral and hexahedron p-version finite element matrices is presented. This new technique separates the integrand into two parts, and numerically operates on each part separately. The objective of this scheme is to minimize the computational cost of integrating the entire element matrix as opposed to minimizing the cost of integrating a single function. The efficiency of the new technique is compared with Gaussian quadrature and found to take a small fraction of the computational effort.
Access flow control algorithms in broadband networks

The authors present and analyze an access flow control algorithm which is applied at the access nodes to the network, specifically, at the input voice and video multiplexers. The algorithm uses a control signal that is proportional to the multiplexer congestion level to throttle the peak bit rate of the input arrival process. The algorithm comprises a continuous type of control rather than the conventional ON/OFF control type. To achieve this, two congestion thresholds (K1, K2) are used to limit the number of cells in the multiplexer buffers. The threshold levels are determined by required quality of service. The authors analyze the resulting quasi-birth-death queueing process for the video-buffer multiplexer. Performance analysis parameters such as the blocking probability and the mean number of bits per sample are presented to evaluated the quality of the video traffic. >
The use of o-nitroarylacetonitriles as carbon acid participants in the mitsunobu reaction

Abstract The use of o -nitroarylacetonitriles as carbon acids in the Mitsunobu reaction is discussed as a method of carboncarbon bond formation. This reaction represents a rare example of a carbon acid participating in a Mitsunobu reaction.
Synthesis, characterization and bonding of Ba3Li4Sn8

Abstract The ternary compound Ba 3 Li 4 Sn 8 was obtained by slow cooling of a stoichiometric mixture of the elements that was heated at 800 °C for 2 days. Its structure (monoclinic, C2/m , Z =2, a =18.549(1), b =6.685(1), c =6.792(1) A, V =833.2(2) A 3 , R 1 / wR 2 =4.03/11.33%) contains one-dimensional chains of 1 ∞ [Sn 8 ] 10− made of edge-sharing cyclodecane-like units in their ‘all-chair’ conformations. The cations screen the chains from each other and provide the extra electrons needed for bonding in the chains. The structure and the electron count can be rationalized in terms of the Zintl concept as (Ba 2+ ) 3 (Li + ) 4 [(2b-Sn 2− ) 2 (3b-Sn 1− ) 6 ], i.e. the compound is an electronically balanced, Zintl phase. Nevertheless, Ba 3 Li 4 Sn 8 exhibits temperature-independent paramagnetism that is, most likely, of van Vleck type as a result of the very small band gap of about 0.3 eV.
TRIPYRIDYLCYCLOPROPENE DERIVATIVES AND THEIR CONVERSION TO HEXAPYRIDYLBENZENE

Abstract 1,2,3-tris(4-pyridyl)cyclopropene carrying a 3-benzenesulfonyl group has been synthesized, and other cyclopropenes carrying pyridine and pyridinium rings. Some of these can be converted to hexa(4-pyridyl)benzene and its pyridinium analog.
Cu Surface Morphology Evolution during Electropolishing

The work examining the evolution of the rough Cu surface morphology during the electropolishing process is presented. The initial Cu surface was produced by electrodeposition under kinetic control. The surface width w is measured for different length scale l and time of the electropolishing experiments t, and the data are analyzed within the scope of the scaling concept and predictions of electropolishing theory. The results indicate that surface width as a function of the length scale for different times of polishing maintains two scaling regimes l lC; w l and l lC; w const. The roughness exponents extracted from the same data show the time dependence described by linear regression. Our analysis of the experimental data demonstrates that decrease of surface width with polishing time is well described by exponential decay predicted by the mathematical model of an ideal electropolishing process. A semiempirical function is proposed to describe the surface width decrease during the electropolishing, and an example of its practical application is discussed.
The impact of monetary policy on bond returns: A segmented markets approach

Abstract This paper assesses the contribution of monetary policy to the dynamics of bond real returns. We assume that the monetary authority controls the short-term nominal interest rate. We then model exogenously the joint dynamics of the aggregate endowment and the monetary policy variable, and determine bond real returns endogenously. Market segmentation is introduced by permanently excluding a fraction of households from financial markets. When markets are segmented, monetary policy has a liquidity effect on the participants’ consumption and marginal utility, on the stochastic discount factor, and on real returns. Data on bond returns strongly favor the segmented markets model over the full participation model. For maturities up to 2 years, the segmented markets model is able to replicate the sign and the size of the impulse response of bond returns to monetary policy shocks, it correctly predicts the sign of their autocorrelation, and it closely matches their volatility as a function of maturity.
The Case for Structured Random Codes in Network Capacity Theorems

Random coding arguments are the backbone of most channel capacity achievability proofs. In this paper, we show that in their standard form, such arguments are insufficient for proving some network capacity theorems: structured coding arguments, such as random linear or lattice codes, attain higher rates. Historically, structured codes have been studied as a stepping stone to practical constructions. However, Korner and Marton demonstrated their usefulness for capacity theorems through the derivation of the optimal rate region of a distributed functional source coding problem. Here, we use multicasting over finite field and Gaussian multiple-access networks as canonical examples to demonstrate that even if we want to send bits over a network, structured codes succeed where simple random codes fail. Beyond network coding, we also consider distributed computation over noisy channels and a special relay-type problem. Copyright (C) 2008 John Wiley & Sons, Ltd.
Synthesis of Carbon-13 Labeled Tetramethyltetrathiafulvalene

Abstract An efficient synthesis of tetramethyltetrathiafulvalene doubly labeled with carbon-13 is described.
The Value Relevance of Network Advantages: The Case of E–Commerce Firms

We show that network advantages constitute an important intangible asset that goes unrecognized in the financial statements. For a sample of e–commerce firms, we find that network advantages created by Web site traffic have substantial explanatory power for stock prices over and above traditional summary accounting measures such as earnings and book value of equity. Also, network advantages are positively associated with one–year–ahead and two–year–ahead earnings forecasts provided by equity analysts. When we allow network advantages to be endogenously determined by managerial actions, we find that at least part of the value relevance of network effects stems from the presence of affiliate referral programs and higher media visibility.
Sampling from spatial databases

This paper deals with techniques for obtaining random point samples from spatial databases. We seek random points from a continuous domain (usually ℝ2) which satisfy a spatial predicate that is represented in the database as a collection of polygons. Several applications of spatial sampling (e.g. environmental monitoring, agronomy, forestry, etc) are described. Sampling problems are characterized in terms of two key parameters: coverage (selectivity), and expected stabbing number (overlap). We discuss two fundamental approaches to sampling with spatial predicates, depending on whether we sample first or evaluate the predicate first. The approaches are described in the context of both quadtrees and R-trees, detailing the sample first, acceptance/rejection tree, and partial area tree algorithms. A sequential algorithm, the one-pass spatial reservoir algorithm is also described. The relative performance of the various sampling algorithms is compared and choice of preferred algorithms is suggested. We conclude with a short discussion of possible extensions.
Supermassive Black Holes in the Hierarchical Universe: A General Framework and Observational Tests

We present a simple framework for the growth and evolution of supermassive black holes (SMBHs) in the hierarchical structure formation paradigm, adopting the general idea that quasar activity is triggered in major mergers. In our model, black hole accretion is triggered during major mergers (mass ratio 0.3) of host dark matter halos. The successive evolution of quasar luminosities follows a universal light-curve (LC) form during which the growth of the SMBH is modeled self-consistently: an initial exponential growth at a constant Eddington ratio of order unity until it reaches the peak luminosity, followed by a power-law decay. Assuming that the peak luminosity correlates with the post-merger halo mass, we convolve the LC with the triggering rate of quasar activity to predict the quasar luminosity function (LF). Our model reproduces the observed LF at 0.5 4.5, in order to reproduce the observed quasar abundance, the typical quasar hosts must shift to lower mass halos, and/or minor mergers can also trigger quasar activity. Our model reproduces both the observed redshift evolution and luminosity dependence of the linear bias of quasar/AGN clustering. Due to the scatter between instantaneous luminosity and halo mass, quasar/AGN clustering weakly depends on luminosity at low-to-intermediate luminosities; but the linear bias rises rapidly with luminosity at the high luminosity end and at high redshift. In our model, the Eddington ratio distribution is roughly lognormal, which broadens and shifts to lower mean values from high luminosity quasars (L bol 1046 erg s-1) to low-luminosity AGNs (L bol 1045 erg s-1), in good agreement with observations. The model predicts that the vast majority of 108.5 M ? SMBHs were already in place by z = 1, and 50% of them were in place by z = 2; but the less massive (107 M ?) SMBHs were assembled more recently, likely more through secular processes than by major mergers?in accordance with the downsizing picture of SMBH assembly since the peak of bright quasar activity around z ~ 2-3.
Estimation of Global Ground Heat Flux

Abstract This study investigates the use of a previously published algorithm for estimating ground heat flux (GHF) at the global scale. The method is based on an analytical solution of the diffusion equation for heat transfer in a soil layer and has been shown to be effective at the point scale. The algorithm has several advantageous properties: 1) it only needs a single-level input of surface (skin) temperature, 2) the time-mean GHF can be derived directly from time-mean skin temperature, 3) it has reduced sensitivity to the variability in soil thermal properties and moisture, 4) it does not requires snow depth, and 5) it is computationally effective. A global map of the necessary thermal inertia parameter is derived using reanalysis data as a function of soil type. These parameter estimates are comparable to values obtained from in situ observations. The new global GHF estimates are generally consistent with the reanalysis GHF output simulated using two-layer soil hydrology models. The authors argue tha...
Enantioselective Synthesis of α,α-Disubstituted Cyclopentenes by an N-Heterocyclic Carbene-Catalyzed Desymmetrization of 1,3-Diketones

The enantioselective synthesis of α,α-disubstituted cyclopentenes using N-heterocyclic carbene catalysis is reported. This desymmetrization reaction proceeds via a chiral enol generated in situ from the combination of an enantiopure azolium salt and α,β-unsaturated aldehyde. This reactive enol undergoes addition to one of two enantiotopic ketones to afford an optically active β-lactone after the intermediate carbinol is involved in an internal acylation event to release the carbene catalyst. In the substrates where R = aryl, a decarboxylation occurs immediately after lactone formation to produce the quaternary center-containing cyclopentene products in up to 96% ee. When the R group is alkyl, the β-lactones are isolated in moderate yield and high diastereo- and enantioselectivity.
Multi-tone millimeter-wave frequency synthesizer for atmospheric propagation studies

The design and test results of a multi-tone millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator is presented. The intended applications of the synthesizer is in a space-borne transmitter for radio wave atmospheric studies at Q-band (37 to 43 GHz). These studies would enable the design of robust high data rate space-to-ground satellite communication links.
Stress-driven diffusive voiding of aluminum conductor lines

The trend to miniaturize silicon integrated circuits has brought with it a thermal stress-induced void formation problem in the aluminum conductor lines of these circuits. Here, local stress relaxation has been included quantitatively in the construction of a wedge-like void growth model. It is shown that under stress relaxation conditions, the stress-induced grain boundary diffusion equation transforms into the diffusion equation. With the use of appropriate boundary conditions and the initial conductor line stress profile, the diffusion equation is solved numerically. This solution yields the temporal history of void size and local stress. It is shown that two types of stress relaxation moderate and limit the growth of voids. From this analysis, a useful expression which relates final void size and initial stress is derived. With these results conservative estimates of the lifetime of aluminum conductor lines can be made. >
Differential privacy for the analyst via private equilibrium computation

We give new mechanisms for answering exponentially many queries from multiple analysts on a private database, while protecting dif- ferential privacy both for the individuals in the database and for the analysts. That is, our mechanism's answer to each query is nearly insensitive to changes in the queries asked by other analysts. Our mechanism is the first to offer differential privacy on the joint distribution over analysts' answers, providing privacy for data an- alysts even if the other data analysts collude or register multiple accounts. In some settings, we are able to achieve nearly optimal error rates (even compared to mechanisms which do not offer an- alyst privacy), and we are able to extend our techniques to handle non-linear queries. Our analysis is based on a novel view of the pri- vate query-release problem as a two-player zero-sum game, which may be of independent interest.
CPW-fed slot antennas on multilayer dielectric substrates

Coplanar wave (CPW)-fed slot antennas printed on multilayer dielectric substrates are numerically analyzed using a full-wave integral equation technique and the method of moments. The Green's function is derived with an iterative formulation. Results obtained with a simplified and a rigorous model of the feeding CPW lines are compared. The mutual coupling between the slot antennas in an array environment is calculated for a three-layer high-low-high permittivity combination. The theoretical results are verified with measurements.
A Method to Remove Fringes from Images Using Wavelets

We have developed a new method that uses wavelet analysis to remove interference fringe patterns from images. This method is particularly useful for flat fields in the common case where fringes vary between the calibration and object data. We analyze the efficacy of this method by creating fake flats with fictitious fringes and removing the fringes. We find that the method removes 90% of the fringe pattern if its amplitude is equal to the random noise level and 60% if the fringe amplitude is ≈1/10 of the noise level. We also present examples using real flat-field frames. A routine written in IDL that implements this algorithm is available from the authors and as an attachment to this paper.
Pockels effect in short period silicon germanium superlattices

We introduce a simple method of calculating Pockels coefficients in ordered SiGe superlattices and show that the Pockels effect in them can be half as strong as in GaAs, thereby opening a path to efficient CMOS-compatible electro-optic modulators.
Contact welding at break of motor inrush current

The contact welding phenomenon observed at automotive relays at switch-off of a dc motor load during startup was investigated. Contact welding occurred during the first operation and was caused by anodic arcs shorter than 80 mus at breaking inrush currents of up to 85 A. The switching performance of the type of relay investigated could be correlated with the parameters: over-travel, release time, and the break current
Vortices in dense self-assembled hole arrays

Abstract We present a study of the upper critical field and pinning strength measured by the resistivity and magnetization of a Nb film containing a dense array of 45 nm diameter holes on a hexagonal lattice with a spacing of 101 nm. The holes were formed by self-assembly in anodic aluminum oxide using an electrochemical procedure. Confinement effects and Little–Parks oscillations are seen above 6 K, and strong pinning with matching field effects is seen below 6 K. Above the first matching field interstitial vortices coexist with vortices trapped in the hole array. Pinning in the Nb films with dense hole arrays is enhanced by two orders of magnitude over that in continuous Nb films. At low temperature, flux avalanches are observed and imaged using the magneto-optical Faraday effect.
Generalizations of Tucker–Fan–Shashkin Lemmas

Tucker and Ky Fan’s lemma are combinatorial analogs of the Borsuk–Ulam theorem (BUT). In 1996, Yu. A. Shashkin proved a version of Fan’s lemma, which is a combinatorial analog of the odd mapping theorem (OMT). We consider generalizations of these lemmas for BUT–manifolds, i.e. for manifolds that satisfy BUT. Proofs rely on a generalization of the OMT and on a lemma about the doubling of manifolds with boundaries that are BUT–manifolds.
Facile redox formation of a 3-substituted maleimide from a 3-substituted N-hydroxysuccinimide

Treatment of 3-(Phenylthio)-N-hydroxysuccinimide 1 with methanesulfonyl chloride and pyridine in dry toluene resulted in the formation of 3-(Phenylthio)maleimide 3a.
Colored Posets and Colored Quasisymmetric Functions

The colored quasisymmetric functions, like the classic quasisymmetric functions, are known to form a Hopf algebra with a natural peak subalgebra. We show how these algebras arise as the image of the algebra of colored posets. To effect this approach, we introduce colored analogs of P-partitions and enriched P-partitions. We also frame our results in terms of Aguiar, Bergeron, and Sottile's theory of combinatorial Hopf algebras and its colored analog.
Elitism, IT and the modern architect opportunity or dilemma

Abstract Information Technology (IT) is impacting architecture dramatically in process and form. Currently, the transformation of architecture is difficult to analyze and, frequently, we see confusion and anxiety regarding uncertainties for the future of the architect as the project leader. The current potentiality for new exotic form (i.e. product) is mesmerizing; however, in the current context, less obvious issues and pertinent questions are emerging for the profession. What is the mission of the profession? What will keep us relevant in the mist of the new global society? In this paper, we will take an evolutionary perspective of technology in architecture and draw parallels between the Renaissance, which is the genesis of the modern architect, and the contemporary state of architecture. The modern architect was birthed during the Renaissance where we see the retraction of the architect from the building site and separation from direct involvement in the building process. Communications technology (i.e. representation in the form of freehand drawings, mechanical 2D orthographic drawings and 3D perspectives) enabled the decomposition of the master builder into three major components (i.e. artist-designer, practicing architect, and builder). Thus, we see technology enable the denigration and ultimate dissolution of the centuries old craftsman guilds and master builder system. The technology evolution of “drawings” enabled monumental change in the process of architecture over the past 500 years. The fission of the master builder, enabled by “drawings”, resulted in disparate factions, which were the forerunners of the modern day litigious design-bid-build project delivery. We now increasingly see a return to the fusion of design and building where often the architect is not the project manager or leader. Thus, the question looms, will the 21st century architect lead or be led, and what are the ramifications for the profession? The historical Master Builder is re-emerging as a dynamically networked team of design and construction knowledge specialists. Bilateral knowledge exchange, enhanced with emerging IT, is occurring between owners, managers, architects, design specialists, engineers, builders, craftsman and machines. Technology is disrupting architecture, resulting in increasing specialization and compressed time frames, and may require reevaluation of the role of the architect as project-leader “integrative-generalist” or “design-specialist”. Conclusively, the concept of ‘cybernetic architecture’ is proposed as an IT reference framework. Failure to appropriately respond to societal evolution, driven by technology, could result in the loss of professional status for the modern architect. Herein lies our dilemma, or opportunity, depending on the role choice of the modern architect.
Optimal Attitude Estimation and Filtering Without Using Local Coordinates Part I: Uncontrolled and Deterministic Attitude Dynamics

Most existing algorithms for attitude estimation of mechanical systems use generalized coordinates to represent the group of rigid body rotations. Generalized coordinate representations of the group of rotations have some associated problems. While minimal (focal) coordinate representations exhibit kinematic singularities for large rotations, the quaternion representation requires satisfaction of an extra constraint. This paper treats the attitude estimation and filtering problem as a deterministic optimization problem, without using generalized coordinates, in the framework of geometric mechanics. An attitude estimation algorithm and filters are developed, that minimize the attitude and angular velocity estimation errors from noisy measurements. For filter propagation, the attitude kinematics and deterministic dynamics equations (Euler's equations) for a body in an attitude-dependent potential are used. Vector attitude measurements, with or without angular velocity measurements, are used for attitude and angular velocity estimation
The archaeology of childhood

The archaeology of childhood has grown over the past decade and a half as a vibrant field of specialized interest within archaeology as a whole. A thematic treatment of the literature highlights a variety of approaches to how and why archaeologists should study children using the archaeological record. These themes are organized chronologically and begin with critiques of archaeological approaches that do not include children and an exploration of the relationship between childhood studies and studies of gender, identity, and agency in the archaeological record. Theoretical and methodological developments that draw attention to new ways of looking at the archaeological record to identify cultural constructions of childhood and lived experiences of children are presented. Finally, current tensions and pluralities in the literature are explored as the archaeology of childhood reaches a new stage in its own maturity as a field of inquiry.
Surface subgroups from homology

Let G be a word-hyperbolic group, obtained as a graph of free groups amalgamated along cyclic subgroups. If H2(G; ℚ) is nonzero, then G contains a closed hyperbolic surface subgroup. Moreover, the unit ball of the Gromov–Thurston norm on H2(G; ℝ) is a finite-sided rational polyhedron.
Peniotron amplifiers with helical wiggler magnetic fields

The performance of peniotron amplifiers which use the axis-encircling beam produced by a combined solenoidal and wiggler magnetic field was investigated through computer simulations. The potential advantages of this new configuration are that it is capable of utilizing both beam longitudinal and transverse energy to amplify injected wave and reducing the severity of mode competition.
Synthesis of epoxybenzo[d]isothiazole 1,1-dioxides via a reductive-Heck, metathesis-sequestration protocol

An atom-economical purification protocol, using solution phase processing viaring-opening metathesis polymerization (ROMP) has been developed for the synthesis of tricyclic sultams. This chromatography-free method allows for convenient isolation of reductive-Heck products and reclamation of excess starting material via sequestration involving metathesis catalysts and a catalyst-armed Si-surface.