cssi/SciSciGPT-SciSciNet huggingface dataset:
Decisions, Science, and Values: Crafting Regulatory Alternatives Analysis

Emerging "prevention-based" approaches to chemical regulation seek to minimize the use of toxic chemicals by mandating or directly incentivizing the adoption of viable safer alternative chemicals or processes. California and Maine are beginning to implement such programs, requiring manufacturers of consumer products containing certain chemicals of concern to identify and evaluate potential safer alternatives. In the European Union, the REACH program imposes similar obligations on manufacturers of certain substances of very high concern. Effective prevention-based regulation requires regulatory alternatives analysis (RAA), a methodology for comparing and evaluating the regulated chemical or process and its alternatives across a range of relevant criteria. RAA has both public and private dimensions. To a significant degree, alternatives analysis is an aspect of product design; that is, the process by which private industry designs the goods it sells. Accordingly, an RAA method should reflect the attributes of well-crafted product design tools used by businesses. But RAA adds health and environmental objectives to the mix of concerns taken into account by the product designer. Moreover, as part of a prevention-based regulatory regime, it implicates important public values such as legitimacy, equity, public engagement, and accountability. Thus, an RAA should reflect both private standards and public values, and be evaluated against them. This article adopts that perspective, identifying an integrated set of design principles for RAA, and illustrating the application of those principles.
Poverty and survival prospects of Vietnamese children under Doi Moi

By international standards, and given its relatively low per capita income, Vietnam has achieved substantial reductions in, and low levels of, infant and under-five mortality. The authors review existing evidence and provide new evidence on whether, under the economic liberalization program known as Doi Moi, this reduction in child mortality has been sustained. They conclude that it has, but that the gains have been concentrated among the better-off. As a result, socioeconomic inequalities in child survival are evident in Vietnam-a change from the early 1990s when none were apparent. The authors develop survival models to find the causes of this differential decline in child mortality, and conclude that a number of factors have been at work, including reductions among the poor (but not among the better-off) in coverage of health services and in women's educational attainment. They argue that if the experience of the late 1990s is a guide to the future, the lack of progress among the poor will jeopardize Vietnam's chances of achieving the international development goals for child mortality. The authors examine various policy scenarios, including expanding coverage of health services, water and sanitation, and find that such measures, while useful, will have only a limited effect on the mortality of poor children. They find that programs aimed at narrowing the gap between the poor and better-off may have large beneficial effects on the various determinants of child survival.
Frequency Space Correlation between REITs and Capital Market Indices

Several studies have examined real estate investment trust (REIT) co-movement with stocks or bonds using traditional time domain based methods, such as linear regression or correlation. Results of these studies have produced inconsistent statistical model parameters. The erratic behavior of the models may have resulted from the different time periods in the studies, the REITs included in a study or the market indices. Another factor contributing to the variation of the models comes from the compression of cyclical information over a study’s time period by time domain based techniques. Cross-spectral analysis provides a frequency space method of examining the coherency (i.e., frequency space correlation) between two time series across all frequencies. This article contains an examination of the coherency between REITs and stock market indices and REITs and U.S. Treasury debt indices for the period 1989-95. Results of the coherency spectra show significant co-movement between REITs and stock market indices,...
Signed‐rank Statistics

In a single sample, or with differences between paired observations in a matched-pair study, the observations may be ranked in order of their absolute values. The sign of the rank is then restored, and an appropriate statistic is calculated from the signed ranks. The most usual example is the Wilcoxon signed-rank test. Keywords: nonparametric; distribution-free; rank; Wilcoxon; tied ranks
Ir-Catalyzed enantioselective group transfer reactions

Recently, several novel iridium complexes have been shown to catalyse group transfer reactions in a highly selective fashion. Rhodium complexes, and in particular dirhodium tetracarboxylate salts, have proven to be a remarkably useful class of catalysts for these reactions through several decades of development. Recent results suggest that iridium may offer opportunities to address challenges in this chemistry and provide complementary reactivity patterns. This tutorial review outlines the recent developments in Ir-catalyzed enantioselective group transfer chemistry with highlights on examples which display this unique reactivity.
Biomimetic hydroxyapatite as a new consolidating agent for archaeological bone

Recent mineral-based approaches for stone and plaster consolidation have demonstrated considerable potential by bio-mimicking the growth of hydroxyapatite (HAP), the main mineralogical constituent of teeth and bone matrices. These initial conservation trials, together with significant fundamental research on the precipitation of HAP for bioengineering and biomedical applications, offer great potential in the use of HAP as a consolidating agent for archaeological bone and other similar matrices such as archaeological teeth, ivory, antler, and fossils. This study presents experimental results on the in situ synthesis of biomimetic HAP-based consolidation processes. Controlled application of diammonium phosphate precursors to bone flour, modern bone samples, and archaeological bones, indicated the formation of HAP with instantaneous increase in the cohesiveness of friable matrices and reduced water absorption while maintaining the physicochemical properties of the samples. These results point towards a promi...
Going (More) Public: Institutional Isomorphism and Ownership Reform among Chinese Firms

Publicly traded Chinese firms recently reformed their ownership structures by converting non-tradable shares, which constituted two-thirds of shares outstanding and were held largely by the state, into shares that could trade on domestic exchanges. To facilitate this reform, tradable shareholders were compensated with stock grants from non-tradable shareholders. Our analysis focuses on the level of compensation, the compensation ratio, the ratio of new tradable shares granted to tradable shares outstanding before the reform. Contrary to the predictions of asset-pricing models, most firms set the compensation ratio around 0.3. We explain this surprising convergence using institutional theory. In doing so, we analyze the power and interests of all relevant actors – not just owners, but also state regulators, executives, and other agents — and draw on insights from resource-dependence and agency theories. We find strong evidence of coercive and mimetic isomorphism, but no evidence of normative isomorphism. Because our dependent variable is continuous (a ratio), we are able to show that the mimetic effects we observe cannot be attributed to coercion or norms. Thus, we not only explain an empirical puzzle, we also advance institutional analysis of isomorphism by clearly distinguishing three isomorphic forces that have been conflated in much previous research.
PhotoCluster a multi-clustering technique for near-duplicate detection in personal photo collections

This paper presents PhotoCluster, a new technique for identifying non-identical near-duplicate images in personal photo collections. Contrary to existing methods, PhotoCluster estimates the probability that a pair of images may be considered near-duplicate. Its main thrust is a multiple clustering step that produces a non-binary near-duplicate probability for each image pair, which exhibits correlation with the average observer opinion. First, PhotoCluster partitions the photolibrary into groups of semantically similar photos, using global features. Then, the multiple clustering step is applied within the images of these groups, using a combination of global and local features. Computationally expensive comparisons between local features are taking place only on a limited part of the library, resulting in a low overall computational cost. Evaluation with two publicly available datasets show that PhotoCluster outperforms existing methods, especially in identifying ambiguous near-duplicate cases.
Isometric Diamond Subgraphs

We test in polynomial time whether a graph embeds in a distance-preserving way into the hexagonal tiling, the three-dimensional diamond structure, or analogous higher-dimensional structures.
Stochastic wavelet-based image modeling using factor graphs and its application to denoising

In this work, we introduce a hidden Markov field model for wavelet image coefficients within a subband and apply it to the image denoising problem. Specifically, we propose to model wavelet image coefficients within subbands as Gaussian random variables with parameters determined by the underlying hidden Markov process. Our model is inspired by the recent Estimation-Quantization (EQ) image coder and its excellent performance in compression. To reduce the computational complexity we apply a novel factor graph framework to combine two 1-D hidden Markov chain models to approximate a hidden Markov Random field (HMRF) model. We then apply the proposed models for wavelet image coefficients to perform an approximate Minimum Mean Square Error (MMSE) estimation procedure to restore an image corrupted by an additive white Gaussian noise. Our results are among the state-of-the-art in the field and they indicate the promise of the proposed modeling techniques.
General affine transform families: why is the Pareto an exponential transform?

A slight extension of the transform method by Efron (1982) is used to analyze general affine transforms of arbitrary random variables. Our application concerns the simple question “Why is the Pareto an exponential transform?”. This result, already known to Gumbel (1958), finds a satisfactory mathematical answer in the framework of general affine transforms, and holds for several other distributions including heavy-tailed ones.
Understanding the dynamics of fractional edge states with composite fermions

Fractional edge states can be viewed as integer edge states of composite fermions. We exploit this to discuss the conductance of the fractional quantized Hall states and the velocity of edge magnetoplasmons.
OBSERVATION OF PHOTOLUMINESCENCE FROM MAGNETO-PLASMAS UNDER INTENSE FEMTOSECOND EXCITATION IN STRONG MAGNETIC FIELDS

We report results on measurements of magneto-photoluminescence at 4.2 K in InxGa1-xAs multiple quantum wells in high magnetic fields (25 Tesla) and laser intensities (25 GW/cm2) using 150 fs pulses. Novel magneto-plasma phenomena are observed, including strikingly narrow emission lines of Landau levels above a threshold intensity and the suppression of exciton-mixing-induced anti-crossings.
Mystery of the volcanic mass‐independent sulfur isotope fractionation signature in the Antarctic ice core

[1] We simulate the record of sulfur mass-independent fractionation (MIF) in sulfates found in the Antarctic ice cores from the 1991 eruption of Mt. Pinatubo. Discovery of MIF in sulfur isotopes in Archean/Early Proterozoic sediments and lack of MIF in sulfur in younger rocks placed a strict upper limit on the amount of oxidants and oxygen in the ancient Earth's atmosphere prior to 2.3 Gyr ago. However, recent measurements in ice cores suggest that some non-zero MIF in sulfate can be delivered to Antarctica following large volcanic eruptions. Current photochemical experiments do not identify the specific reaction responsible for sulfur MIF production. Here we show that a time-dependent non-zero sulfur MIF can be delivered to the ground in the present atmosphere if the MIF–producing process is SO3 photolysis. Fractionation from such photolysis has not been considered before, but is consistent with the available experimental data.
Regularization and renormalization of quantum field theory in curved space-time

It is proposed that field theories quantized in a curved space-time manifold can be conveniently regularized and renormalized with the aid of Pauli--Villars regulator fields. The method avoids the conceptual difficulties of covariant point-separation approaches, by always starting from a manifestly generally covariant action, and the technical limitations of the dimensional regularization approach, which requires solution of the theory in arbitrary dimension in order to go beyond a weak-field expansion. An action is constructed which renormalizes the weak-field perturbation theory of a massive scalar field in two space-time dimensions, it is shown that the trace anomaly previously found in dimensional regularization and some point-separation calculations also arises in perturbation theory when the theory is Pauli--Villars regulated. We then study a specific solvable two-dimensional model of a massive scalar field in a Robertson--Walker asymptotically flat universe. It is shown that the action previously considered leads, in this model, to a well-defined finite expectation value for the stress-energy tensor. The particle production ( for t..-->..+infinity) is computed explicitly. Finally, the validity of weak-field perturbation theory (in the appropriate range of parameters) is checked directly in the solvable model, and the trace anomaly computed in the asymptoticmore » regions t..-->.. +- infinity independently of any weak-field approximation. The extension of our model to higher dimensions and the renormalization of interacting (scalar) field theories are briefly discussed.« less
Ruthenium-promoted diaryl ether synthesis in the construction of the F-O-G ring system of a teicoplanin model

An end-game approach is described for the synthesis of glycopeptide antibiotics related to teicoplanin, using ruthenium-promoted diaryl ether formation, followed by cycloamidation.
Empty Simplices of Polytopes and Graded Betti Numbers

The conjecture of Kalai, Kleinschmidt, and Lee on the number of empty simplices of a simplicial polytope is established by relating it to the first graded Betti numbers of the polytope and applying a result of Migliore and the author. This approach allows us to derive explicit optimal bounds on the number of empty simplices of any given dimension. As a key result, we prove optimal bounds for the graded Betti numbers of any standard graded K-algebra in terms of its Hilbert function.
Chemotherapy of disseminated germ cell tumors

The fact that germ cell tumors can be successfully managed puts an extraordinary burden on the physician and health care system to ensure that the promise of cure is achieved in all patients except the small proportion that present with advanced refractory disease. Good risk disseminated disease should be treated with three cycles of bleomycin, etoposide and cisplatin (BEP) whereas those with more advanced disease should receive four cycles. Postchemotherapy resection of residual disease is commonly required. In patients in whom disease recurs after primary chemotherapy, salvage treatments can result in cure in 30-40% of patients. Physicians managing these patients should be aware of some of the pitfalls encountered when determining relapse and should be versed in the indications for salvage conventional dose chemotherapy, high dose chemotherapy, and the role of aggressive desperation surgery.
Observation of nuclear fusion driven by a pyroelectric crystal

Many methods of reproducing nuclear fusion — the process that powers the Sun — at the table-top scale have been tried, but failed to convince. Remember ‘cold fusion’? More recently, fusion linked to sonoluminescence is still controversial. Now comes a claim from the labs of the University of California at Los Angeles of unequivocal evidence of nuclear fusion in a simple room-temperature experiment. They report that gently heating a pyroelectric crystal — material that becomes charged when heated — causes ionization of a surrounding deuterium gas. The ions bombard a deuterated solid target with such energy that a large neutron signal is detected, a hallmark of deuterium fusion. Though not a viable power source, ‘crystal fusion’ may find application as a generator of neutrons for imaging technology. While progress in fusion research continues with magnetic1 and inertial2 confinement, alternative approaches—such as Coulomb explosions of deuterium clusters3 and ultrafast laser–plasma interactions4—also provide insight into basic processes and technological applications. However, attempts to produce fusion in a room temperature solid-state setting, including ‘cold’ fusion5 and ‘bubble’ fusion6, have met with deep scepticism7. Here we report that gently heating a pyroelectric crystal in a deuterated atmosphere can generate fusion under desktop conditions. The electrostatic field of the crystal is used to generate and accelerate a deuteron beam (> 100 keV and >4 nA), which, upon striking a deuterated target, produces a neutron flux over 400 times the background level. The presence of neutrons from the reaction D + D → 3He (820 keV) + n (2.45 MeV) within the target is confirmed by pulse shape analysis and proton recoil spectroscopy. As further evidence for this fusion reaction, we use a novel time-of-flight technique to demonstrate the delayed coincidence between the outgoing α-particle and the neutron. Although the reported fusion is not useful in the power-producing sense, we anticipate that the system will find application as a simple palm-sized neutron generator.
Estimation of Structural Response Using Remote Sensor Locations

A method is presented for estimating the response of a structure during its operation at discrete locations that are inaccessible for measurement using sensors. The prediction is based on measuring response at other locations on the structure and transforming it into the response at the desired locations using a transformation matrix. The transformation is computed using the system Markov parameters determined from a vibration test in which the response is measured both at the locations that will possess sensors during structure operation and at the desired locations thatwill not possess sensors. Two different approachesareconsidered. Thee rst requires as many sensors as there are modes responding in the data. The second approach, a generalization of the e rst, only requires as many sensors as the number of input locations. The transformation matrix is shown to consist of a set of inverse system Markov parameters, which can be related to a corresponding observer formulation. A numerical example is considered using the controls-structures interaction evolutionary model testbed at NASA Langley Research Center. Acceleration response with 10% rms noise at six sensor locations is used to predict the response at four force input locations. The proposed method is not computationally intensive and, combined with the fact that the process is causal, may allow real-time applications.
Calculating Benzene Concentration Emitted During Tanker Loading

Benzene emissions occur during marine vessel loading operations. These emissions are regulated in several countries. Accordingly, we developed a one-dimensional benzene diffusion model advancing in the vertical direction within cargo tanks. Unlike other models, the model presented in this paper is based on a 1/10 scale modeling of eddy diffusion at the liquid surface during initial loading operations and advection under the tank roof during final loading operations. The model input parameters include loading rate, flow rate, cargo tank size, and temperature dependent saturated concentrations. The validity of the model is demonstrated by comparisons with onboard measurements. Other models exist. However, they are based on empirical estimates rather than rational modeling.
The X-Ray Size-Temperature Relation for Intermediate-Redshift Galaxy Clusters

We present the first measurements of the X-ray size-temperature (ST) relation in intermediate-redshift (z ~ 0.30) galaxy clusters. We interpret the local ST relation (z ~ 0.06) in terms of underlying scaling relations in the cluster dark matter properties, and then we use standard models for the redshift evolution of those dark matter properties to argue that the ST relation does not evolve with redshift. We then use ROSAT HRI observations of 11 clusters to examine the intermediate-redshift ST relation; for currently favored cosmological parameters, the intermediate-redshift ST relation is consistent with that of local clusters. Finally, we use the ST relation and our evolution model to measure angular diameter distances; with these 11 distances we evaluate constraints on ΩM and ΩΛ that are consistent with those derived from studies of Type Ia supernovae. The data rule out a model with ΩM = 1 and ΩΛ = 0 with 2.5 σ confidence. When limited to models where ΩM + ΩΛ = 1, these data are inconsistent with ΩM = 1 with 3 σ confidence.
A Test Against Spurious Long Memory

This paper proposes a test statistic for the null hypothesis that a given time series is a stationary long-memory process against the alternative hypothesis that it is affected by regime change or a smoothly varying trend. The proposed test is in the frequency domain and is based on the derivatives of the profiled local Whittle likelihood function in a degenerating neighborhood of the origin. The assumptions used are mild, allowing for non-Gaussianity or conditional heteroscedasticity. The resulting null limiting distribution is free of nuisance parameters and can be easily simulated. Furthermore, the test is straightforward to implement; in particular, it does not require specifying the form of the trend or the number of different regimes under the alternative hypothesis. Monte Carlo simulation shows that the test has decent size and power properties. The article also considers three empirical applications to illustrate the usefulness of the test. This article has supplementary material online.
New clues for understanding the magnetic behavior of UPt3

Abstract We present results of a fairly complete study on which dopants M result in single-phase U1−xMxPt3 samples. The resulting new samples. M = Y, Lu, Sc, Hf, Zr, have been characterized by low temperature magnetic susceptibility and specific heat for x ⩽ 0.07. Based on a previously proposed model, the c a ratios of the present alloys would be expected to result in magnetic behavior as observed in U1−xThxPt3 and U(Pt1−xPdx)3. On the contrary, no magnetism is found; the Sc-doped samples actually show a suppression of spin fluctuations. A new proposal is made to explain which properties are critical for the magnetic behavior of UPt3, as well as its doped derivatives.
Uniqueness of a solution of a steady state photochemical problem: Applications to Mars

Based on the conservation of chemical elements in chemical reactions, a rule is proved that the number of boundary conditions given by densities and/or nonzero velocities should not be less than the number of chemical elements in the system, and the boundary conditions for species given by densities and velocities should include all elements in the system. Applications of this rule to Mars are considered. It is shown that the problem of the CO2-H2O chemistry in the lower and middle atmosphere of Mars, say, in the range of 0-80 km does not have a unique solution, if only CO2 and H2O densities are given at the lower boundary, and the remaining boundary conditions are fluxes. Two examples of models of this type are discussed. Two models of the photochemistry of the Martian atmosphere, with and without nitrogen chemistry, are considered. The oxygen nonthermal escape ratio of 1.2 x 10(exp 8)/cu cm/s is given at 240 km and is balanced with the total hydrogen escape rate within an uncertainty of 1% for both models. Both models fit the measured O2 and CO mixing ratios, the O3 abundance, and the O2 1.27-micrometer dayglow almost within the uncertainties of the measured values, though the model without nitrogen chemistry fits better. The importance of nitrogen chemistry in the lower and middle atmosphere of Mars depends on a fine balance between production of NO and N in the upper atmosphere which is not known within the required accuracy.
You Can't Get Away with Murder That Easily: A Response to Timothy Mulgan

In his article ‘How Satisficers Get Away with Murder’, Tim Mulgan argues that satisficing consequentialism cannot make good on its promise to avoid the Demandingness Objection, while at the same ti...
HIGH SPEED DIGITAL CIRCUIT TECHNOLOGY

The performance of high speed digital integrated circuits, defined here as those requiring operation at high clock frequency, is generally more sensitive to material properties and process techniques than ICs used at lower frequencies. Obtaining high speed and low power concurrently is especially challenging. Circuit architectures must be selected for the device and application appropriately. This paper presents simple models for high speed digital IC performance and applies these to the FET and bipolar transistor. Heterojunction devices are compared with those using single or binary materials. Circuits for high speed SSI and low power VLSI applications are described, and their performance is surveyed.
Betti numbers and injectivity radii

We give lower bounds on the maximal injectivity radius for a closed hyperbolic 3-manifold with first Betti number 2 under some additional topological hypotheses.
The redshift determination of GRB 990506 and GRB 000418 with the Echellete Spectrograph Imager on Keck

Using the Echellete Spectrograph Imager (ESI) on the Keck II 10 m telescope we have measured the redshifts of the host galaxies of gamma-ray bursts GRB 990506 and GRB 000418, z = 1.30658 ± 0.00004 and 1.1181 ± 0.0001, respectively. Thanks to the excellent spectral resolution of ESI (λ/Δλ = 13000), we resolved the [O II] λ3727 doublet in both cases. The measured redshift of GRB 990506 is the highest known for a dark-burst GRB, though entirely consistent with the notion that dark and non–dark bursts have a common progenitor origin. The relative strengths of the [O II], He I, [Ne III], and Hγ emission lines suggest that the host of GRB 000418 is a starburst galaxy, rather than a LINER or Seyfert 2. Since the host of GRB 000418 has been detected at submillimeter wavelengths, these spectroscopic observations suggest that the submillimeter emission is due to star formation (as opposed to AGN) activity. The [O II]-derived unobscured star formation rates are 13 and 55 M⊙ yr-1 for the hosts of GRB 990506 and GRB 000418, respectively. In contrast, the star formation rate of the host of GRB 000418 derived from submillimeter observations is 20 times larger.
A general method for deprotection of N-toluenesulfonyl aziridines using sodium naphthalenide

Abstract Deprotection of a variety of N-tosylaziridines with sodium naphthalenide provided the corresponding N-H-aziridines in excellent yield. No single electron transfer (SET) induced aziridine ring opening was seen under the conditions employed for the deprotection reaction.
Ventilated Oscillatory Boundary Layers

Boundary layers arising from flows which oscillate parallel to a permeable bed, and are subject to oscillating percolation of the same frequency as the bed parallel flow, referred to here as ‘ventilated oscillatory boundary layers’, are the subject of this laboratory study. These boundary layers are intended to approximate naturally occurring wave boundary layers over permeable beds. Measurements of boundary-layer velocities, bed stress and turbulent flow properties are presented. It is observed that suction (flow into the bed) enhances the near-bed velocities and bed stress while injection (flow out of the bed) leads to a reduction in these quantities. As the ventilated oscillatory boundary layer experiences both these phenomenon in one full cycle, the result is a net stress and a net boundary-layer velocity in an otherwise symmetric flow. While production of turbulence attributable to injection is enhanced, the finite time required for this to occur leads to a greater vertically averaged turbulence in the suction half-cycle. Turbulence generated in the suction half-cycle is maintained in a compact layer much closer to the bed. These effects appear to hold for ranging from 105 to 106 and for oscillations other than sinusoidal.
Variation of Heegner points in Hida families

Given a weight two modular form f with associated p-adic Galois representation V f , for certain quadratic imaginary fields K one can construct canonical classes in the Galois cohomology of V f by taking the Kummer images of Heegner points on the modular abelian variety attached to f. We show that these classes can be interpolated as f varies in a Hida family and construct an Euler system of big Heegner points for Hida’s universal ordinary deformation of V f . We show that the specialization of this big Euler system to any form in the Hida family is nontrivial, extending results of Cornut and Vatsal from modular forms of weight two and trivial character to all ordinary modular forms, and propose a horizontal nonvanishing conjecture for these cohomology classes. The horizontal nonvanishing conjecture implies, via the theory of Euler systems, a conjecture of Greenberg on the generic ranks of Selmer groups in Hida families.
Counting the number of excited states in organic semiconductor systems using topology

Exciton scattering theory attributes excited electronic states to standing waves in quasi-one-dimensional molecular materials by assuming a quasi-particle picture of optical excitations. The quasi-particle properties at branching centers are described by the corresponding scattering matrices. Here, we identify the topological invariant of a scattering center, referred to as its winding number, and apply topological intersection theory to count the number of quantum states in a quasi-one-dimensional system.
The term structure of very short-term rates: New evidence for the expectations hypothesis ☆

Abstract Empirical researchers have frequently rejected the expectations hypothesis. The expectations hypothesis, however, has seldom, if ever, been tested at the extreme short end of the term structure where maturities are measured in days or weeks. Using overnight, weekly, and monthly repo rates, I find that term rates are almost unbiased estimates of the average overnight rate. This evidence provides new support for the expectations hypothesis.
Morphological Transformation of Pd Thin Film Catalysts during 1,3-Butadiene Hydrogenation: An Air and UHV STM Study

The surface morphology of supported Pd/graphite film catalysts imaged by scanning tunneling microscopy (STM) shows that the microstructure is strongly dependent on the pretreatment and reaction conditions. Results obtained from the ultrahigh vacuum STM have validated the ambient STM images provided the film structures are sufficiently larger than 10 nm. Significant morphological changes occurring during reaction were accompanied by alteration in the activity and selectivity. Three Pd/HOPG films were prepared by exposure to different treatment conditions. It was found that the films with different microstructure exhibit different catalytic behavior, whereas the two films with similar structures prepared by different procedures have similar activity and selectivity.
The Curious Radial Distributions of Horizontal Branch Stars in NGC 6441

NGC 6441 is one of the most massive and most metal-rich globular clusters in the galaxy, and is noted for an unusual extended horizontal branch that reaches past the instability strip. We find evidence that there are two different populations of stars within the heavily populated red clump. Once a differential reddening correction is applied, a large but compact group of stars is found at the faint red end of the clump in the color-magnitude diagram. Brighter, bluer stars in the clump are found to be more centrally concentrated within the cluster at a very high level of significance. Curiously, the blue horizontal branch stars show a more complex distribution and are not more centrally concentrated than the brighter red clump stars. The spatial distributions of clump stars are in agreement with the idea that the brighter bluer part of the clump is a helium-enriched second generation. The blue horizontal branch stars may be showing evidence that they are being dynamically evaporated.
A sensor network application construction kit (SNACK)

We propose a new configuration language, component and service library, and compiler that make it easier to develop efficient sensor network applications. Our goal is the construction of smart application service libraries: high-level libraries that implement concepts like routing trees and periodic sensing, and that combine automatically into efficient programs. Important language features include flexible control over component sharing and transitive arrow connections, which let independently-implemented services knit themselves into integrated control flow paths. Our language, library, and compiler are collectively called SNACK (Sensor Network Application Construction Kit). We describe them, and present and evaluate a simple SNACK-based multihop data collection application. This application uses SNACK language features to provide both simplicity (excluding reusable service definitions, its description is three lines long) and efficiency (it performs comparably to the well-known Surge application).
Digital Microfluidic Biochips: A Vision for Functional Diversity and More than Moore

Microfluidics-based biochips are revolutionizing high-throughput sequencing, parallel immunoassays, clinical diagnostics, and drug discovery. These devices enable the precise control of nanoliter volumes of biochemical samples and reagents. Compared to conventional laboratory procedures, which are cumbersome and expensive, miniaturized biochips offer the advantages of higher sensitivity, lower cost due to smaller sample and reagent volumes, system integration, and less likelihood of human error. This embedded tutorial paper provides an overview of droplet-based “digital” microfluidic biochips. It describes emerging computer-aided design (CAD)tools for the automated synthesis and optimization of biochips from bioassay protocols. Recent advances in fluidic-operation scheduling, module placement, droplet routing, pin-constrained chip design, and testing are presented.
Software-defined quantum communication systems

Quantum communication (QC) systems harness modern physics through state-of-the-art optical engineering to provide revolutionary capabilities. An important concern for QC engineering is designing and prototyping these systems to evaluate the proposed capabilities. We apply the paradigm of software-defined communication for engineering QC systems to facilitate rapid prototyping and prototype comparisons. We detail how to decompose QC terminals into functional layers defining hardware, software, and middleware concerns, and we describe how each layer behaves. Using the superdense coding protocol as an example, we describe implementations of both the transmitter and receiver, and we present results from numerical simulations of the behavior. We conclude that the software-defined QC provides a robust framework in which to explore the large design space offered by this new regime of communication.
Speed of optically-controlled superconducting devices

The speed of optically controlled superconducting devices is discussed. The results of experimental measurements on the speed of nonequilibrium carrier recombination are reviewed. These results indicate that a voltage change can be induced in YBCO samples by a short laser pulse. It is shown that high-Tc superconducting devices can potentially operate in the subpicosecond regime.
Longitudinal slots in dielectric‐filled rectangular waveguides

A longitudinal radiating slot cut in a broad wall of a dielectric filled rectangular waveguide is analyzed rigorously. Pertinent coupled integral equations for the aperture electric field of a thick wall slot are solved by the method of moments. Numerical results are presented for the slot characteristics over a range of permittivity values of the dielectric. Shunt admittance representation is found to be poor for higher values of the dielectric permittivity. © 1993 John Wiley & Sons, Inc.
On the NLIE of (inhomogeneous) open spin-1 XXZ chain with general integrable boundary terms

Starting from the T-Q equations of the open spin-1 XXZ quantum spin chain with general integrable boundary terms, for values of the boundary parameters which satisfy a certain constraint, we derive a set of nonlinear integral equations (NLIEs) for the inhomogeneous open spin-1 XXZ chain. By taking the continuum limit of these NLIEs, and working in analogy with the open spin-1 XXZ chain with diagonal boundary terms, we compute the boundary and the Casimir energies of the corresponding supersymmetric sine-Gordon (SSG) model. We also present an analytical result for the effective central charge in the ultraviolet (UV) limit.
Novel conductive adhesives for surface mount applications

Electrically conductive adhesives (ECAs) have been explored as a tin/lead (Sn/Pb) solder alternative for attaching encapsulated surface mount components on rigid and flexible printed circuits. However, limited practical use of conductive adhesives in surface mount applications is found because of the limitations and concerns of current commercial ECAs. One critical limitation is the significant increase of joint resistance with Sn/Pb finished components under 85°C/85% relative humidity (RH) aging. Conductive adhesives with stable joint resistance are especially desirable. In this study, a novel conductive adhesive system that is based on epoxy resins has been developed. Conductive adhesives from this system show very stable joint resistance with Sn/Pb-finished components during 85°C/85% RH aging. One ECA selected from this system has been tested here and compared with two popular commercial surface mount conductive adhesives. ECA properties studied included cure profile, glass transition temperature (Tg), bulk resistivity, moisture absorption, die shear adhesion strength, and shift of joint resistance with Sn/Pb metallization under 85°C/85% RH aging. It was found that, compared to the commercial conductive adhesives, our in-house conductive adhesive had higher Tg, comparable bulk resistivity, lower moisture absorption, comparable adhesion strength, and most importantly, much more stable joint resistance. Therefore, this conductive adhesive system should have better performance for surface mount applications than current commercial surface mount conductive adhesives. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 399–406, 1999
Growth and Zeros of the Zeta Function for Hyperbolic Rational Maps

This paper describes new results on the growth and zeros of the Ruelle zeta function for the Julia set of a hyperbolic rational map. It is shown that the zeta function is bounded by exp(CK |s| � ) in strips |Re s| ≤ K, whereis the dimension of the Julia set. This leads to bounds on the number of zeros in strips (interpreted as the Pollicott-Ruelle resonances of this dynamical system). An up- per bound on the number of zeros in polynomial regions {|Re s| ≤ |Im s| � } is given, followed by weaker lower bound estimates in strips {Re s > −C, |Im s| ≤ r}, and logarithmic neighbourhoods {|Re s| ≤ �log |Im s|}. Recent numerical workof Strain-Zworski suggests the upper bounds in strips are optimal.
Approximate Minimum Energy Control

A computationally simple approximation to the minimum energy controller for a linear system is achieved by reducing the complexity of the mathematical model of the system. After specifying the criterion for identifying an optimal model of lower order, the required model boundary conditions are deduced. Controller performance is expressed as a scalar valued functional of the model coefficient matrices, and a computational algorithm is suggested for evaluating the best model. The suboptimal control is then expressed in terms of the derived model parameters.
Adverse‐Selection Costs and the Probability of Information‐Based Trading

Prior studies offer various empirical models to decompose the observed bid-ask spread into the adverse-selection and transitory (order-processing and inventory-holding) components. There is limited evidence, however, on whether the spread components estimated from these models indeed measure what they purport to measure. In this study, we show that the estimates of the adverse-selection component given by these models are positively and significantly related to the probability of information-based trading (PIN), after controlling for the endogeneity of the PIN and other stock attributes. These results provide direct empirical support for the spread component models examined in the present study.
Adaptive learning of semantic locations and routes

Adaptation of devices and applications based on contextual information has a great potential to enhance usability and mitigate the increasing complexity of mobile devices. An important topic in context-aware computing is to learn semantic locations and routes of mobile device users. Several batch methods have been proposed to learn these locations. However, such offline methods have very limited usefulness in practice. This paper describes an online adaptive approach to learn user's semantic locations. The proposed method models user's GPS data as a mixture of Gaussians, which is updated by an online estimation. The learned Gaussian mixture is then evaluated to determine which components most likely correspond to the important locations based on a priori probabilities. With learned semantic locations, we also propose a minimax criterion to discover user's frequent transportation routes, which are modeled as sequences of GPS data. Finally, we describe an application of the proposed methods in a cell phone based automatic traffic advisory system.
Low Vitamin D Status: Definition, Prevalence, Consequences, and Correction

Low vitamin D status is extremely common worldwide due to low dietary intake and low skin production. Suboptimal vitamin D status contributes to many conditions, including osteomalacia/rickets, osteoporosis, falls, and fractures. It is possible or even likely that low vitamin D status increases risk for a multitude of other conditions. Although consensus does not exist, it appears that circulating 25(OH)D concentrations greater than 30 to 32 ng/mL are needed for optimal health. To achieve this, daily intakes of at least 1000 IU of D3 daily are required, and it is probable that substantially higher amounts are required to achieve such values on a population basis. It seems premature to recommend widespread screening for 25(OH)D measurement. Targeted measurement in those at increased risk for vitamin D deficiency and those most likely to have a prompt positive response to supplementation is appropriate. Widespread optimization of vitamin D status likely will lead to prevention of many diseases with attendant reduction of morbidity, mortality, and expense.
Uniform complexity and digital signatures

Abstract A concept of uniform complexity is defined and a class of functions is shown to have uniform complexity. A special case of these results is used to develop a new digital signature method, which makes forging signatures as hard as factoring a large number and which allows half of the messages to be signed directly. The signature production involves only one exponentiation modulo a large number and the signature checking the comparison of a fourth and second power modulo a large number. Therefore this new method is faster than known methods with the same degree of safety.
A Human Factors Evaluation of Stethoscopes

Background: The need to hear sounds of the human body is important in health care. The stethoscope was designed to improve practitioner’s method of “immediate auscultation.” The purpose of this study was to evaluate and compare 16 human factor characteristics of two electrically amplified and one standard acoustic stethoscope. Methods: Each subject examined the three stethoscopes by listening to heart sounds of the investigator. After examination, each of the 77 subjects evaluated the stethoscopes by completing a questionnaire according to the following categories: sound, comfort, ease of use, and instruction manuals. Subjects ranged in age from 18 to 67 years, with 51 % of the subjects having prior experience with stethoscopes. Results: Both electronically amplified stethoscopes were found to have a significant difference in regard to preference compared with the non-electronically amplified standard stethoscope on all characteristics. No significant differences were found between the two electronically amplified stethoscopes, with the exception of turning the stethoscopes on and off. The average mean ratings of the two electronically amplified stethoscopes were not significantly different. Conclusion: It is clear that electronic amplification was preferred over acoustically amplified sound in this study. As the complexity increases with electronic amplification, the importance of ease-of-use design becomes more important.
Oxidant-controlled stereoselectivity in the Pd-catalyzed allylic oxidation of cis-vinylsilanes.

The allylic oxidation of cis-vinylsilanes is reported. The reaction requires a low catalyst loading of Pd(OAc)2 without the need for an external ligand. Interestingly, trans-vinylsilanes are unreactive, whereas allylic oxidations of cis-vinylsilanes proceed in good yields giving a single diastereo- and regioisomer of the branched allylic acetate trans-vinylsilane when benzoquinone is employed. The use of PhI(OAc)2 as oxidant in place of benzoquinone provides the branched, cis-vinylsilane as the major product. Additionally, the first intramolecular allylic C–H etherifications of cis-vinylsilanes to give oxygen heterocycles are also described.
Three-dimensional loop quantum gravity: physical scalar product and spin-foam models

In this paper, we address the problem of the dynamics in three-dimensional loop quantum gravity with zero cosmological constant. We construct a rigorous definition of Rovelli's generalized projection operator from the kinematical Hilbert space—corresponding to the quantization of the infinite-dimensional kinematical configuration space of the theory—to the physical Hilbert space. In particular, we provide the definition of the physical scalar product which can be represented in terms of a sum over (finite) spin-foam amplitudes. Therefore, we establish a clear-cut connection between the canonical quantization of three-dimensional gravity and spin-foam models. We emphasize two main properties of the result: first that no cut-off in the kinematical degrees of freedom of the theory is introduced (in contrast to standard 'lattice' methods), and second that no ill-defined sum over spins ('bubble' divergences) are present in the spin-foam representation.