cssi/SciSciGPT-SciSciNet huggingface dataset:
Funicular state in drying of a porous slab

Abstract Drying of a non-hygroscopic porous slab initially saturated with liquid, up to the time of the first appearance of dried patches (critical time), is studied experimentally using glass beads and convective heating, and analytically using the volume averaged conservation equations for capillary driven liquid flow and empirical constitutive relations. Good agreement has been found between the predicted and measured results and the results show that: 1. (a) The surface mass transfer rate depends on the surface saturation. This surface saturation coefficient, which is also a function of both surface geometry and the free stream velocity, is determined experimentally. 2. (b) The critical time is a ratio of the internal liquid transport conductance (Peclet number) to the external vapor transport conductance (Biot number).
Parameter and state estimation of experimental chaotic systems using synchronization

We examine the use of synchronization as a mechanism for extracting parameter and state information from experimental systems. We focus on important aspects of this problem that have received little attention previously and we explore them using experiments and simulations with the chaotic Colpitts oscillator as an example system. We explore the impact of model imperfection on the ability to extract valid information from an experimental system. We compare two optimization methods: an initial value method and a constrained method. Each of these involves coupling the model equations to the experimental data in order to regularize the chaotic motions on the synchronization manifold. We explore both time-dependent and time-independent coupling and discuss the use of periodic impulse coupling. We also examine both optimized and fixed (or manually adjusted) coupling. For the case of an optimized time-dependent coupling function u(t) we find a robust structure which includes sharp peaks and intervals where it is zero. This structure shows a strong correlation with the location in phase space and appears to depend on noise, imperfections of the model, and the Lyapunov direction vectors. For time-independent coupling we find the counterintuitive result that often the optimal rms error in fitting the model to the data initially increases with coupling strength. Comparison of this result with that obtained using simulated data may provide one measure of model imperfection. The constrained method with time-dependent coupling appears to have benefits in synchronizing long data sets with minimal impact, while the initial value method with time-independent coupling tends to be substantially faster, more flexible, and easier to use. We also describe a method of coupling which is useful for sparse experimental data sets. Our use of the Colpitts oscillator allows us to explore in detail the case of a system with one positive Lyapunov exponent. The methods we explored are easily extended to driven systems such as neurons with time-dependent injected current. They are expected to be of value in nonchaotic systems as well. Software is available on request.
Solid solutions of Pd containing hydrogen and a noble-metal substitutional component—I. Thermodynamic behavior

Abstract Elastic data have been measured for Pd-based solid solutions containing Cu, Au, and Ag in the concentration range 0–50 at.% of substitutional solute and in the temperature range 300–1200 K. The elastic data have been used to evaluate a statistical mechanical model for solid solutions of hydrogen in Pd-based solutions containing noble metals. The elastic data are used to calculate that contribution to the partial thermodynamic functions of the dissolved interstitial atoms which arises due to the change in the specific volume of the metal lattice as the substitutional atom concentration is varied.
Episodic Mass Transfer: A Trigger for Nova Outbursts?

High resolution spectra of post-outburst novae show multiple components of ejected gas that are kinematically distinct. We interpret the observations in terms of episodes of enhanced mass transfer originating from the secondary star that result in the formation of discrete components of circumbinary gas and accretion onto the white dwarf (WD) that trigger nova outbursts. In this picture the concordance between absorption line velocities and emission line widths in most novae occurs as a result of the collision of the expanding nova ejecta with a larger mass of surrounding circumbinary gas. One implication of this model is that much of the accreted gas remains on the WD, leading to a secular increase in WD mass over each outburst event. Alternative scenarios to explain nova spectral evolution are possible that do not invoke circumbinary gas and a possible test of different models is proposed.
A posteriori analysis of low-pass spatial filters for approximate deconvolution large eddy simulations of homogeneous incompressible flows

The goal of this paper is twofold: first, it investigates the effect of low-pass spatial filters for approximate deconvolution large eddy simulation (AD-LES) of turbulent incompressible flows. Second, it proposes the hyper-differential filter as a means of increasing the accuracy of the AD-LES model without increasing the computational cost. Box filters, Pade filters, and differential filters with a wide range of parameters are studied in the AD-LES framework. The AD-LES model, in conjunction with these spatial filters, is tested in the numerical simulation of the two-dimensional and three-dimensional Taylor–Green vortex problems. We show that the most accurate results are obtained with the hyper-differential filter, followed by the differential filter. We also demonstrate that the results highly depend on the selection of the filtering procedure. It seems that filters whose transfer function resembles that of the Fourier cut-off filter (such as the hyper-differential filters) tend to perform the best.
One-dimensional leakage-flow vibration instabilities

Simple boundary conditions, pressure losses, and channel geometries necessary for the unstable, rigid-body translational vibrations of the wall of a one-dimensional leakage-flow channel are identified. General expressions for the flow-damping and stiffness forces acting on the vibrating channel wall are derived and specific results are given for channels with wall friction, point pressure losses, sharp-edged constrictions, and diverging or converging widths. The minimum conditions necessary for dynamic and static (divergence) instability were found to be an upstream point pressure loss and a diverging channel width with a finite-length throat region, respectively.
Genetic/epidemiological findings in a study of smoking-associated tumors.

Abstract While the etiology of bronchogenic carcinoma remains enigmatic, an expanding array of carcinogenic pollutants in interaction with host susceptibility factors has been implicated. We have studied family histories of cancer in a consecutive series of cancer patients from two university oncology clinics in Nebraska. Particular attention has been given to carcinoma of the lung and other putative smoking-associated cancers (oral cavity, esophagus, urinary bladder, pancreas). Smoking histories were obtained for relatives of an overlapping series of patients with these tumor sites. Findings revealed that, although a significant cohort effect was observed with respect to smoking habits for both relatives of lung cancer probands and for relatives of probands with other smoking-associated tumors, a corresponding trend for lung cancer frequency was observed only for relatives of lung cancer probands. This result suggests the importance of host factors in combination with environmental exposures in determining lung risk. A cohort trend for lung cancer was also apparent among relatives of breast cancer probands, but not for relatives of colon cancer probands, suggesting the possibility of an intrinsic association between carcinomas of the breast and lung. We believe that further elucidation of host factor susceptibility in lung cancer may have important etiological and preventive implications.
Analysis of granulocyte-macrophage progenitor cells in patients treated with recombinant interferon alpha-2

Abstract The most common dose-limiting toxicity of alpha interferon has been leukopenia. It is well documented that interferon inhibits human multipotential, erythroid, and granulocyte-macrophage progenitor cells in vitro. Granulocyte-macrophage progenitor cells were evaluated by a colony-forming assay in patients treated with recombinant interferon alpha-2, and results of the assay were correlated with histologic findings in the same bone marrow aspirates and biopsy specimens from the same patients. Eleven patients received 10 million units/m 2 interferon subcutaneously thrice weekly for three months. The bone marrow was evaluated on Day -3 (pretreatment) and Day 10 of treatment. Colony-forming granulocyte-macrophage cell count fell from 40.9 ± 7.6 colonies per 10 5 cells before treatment to 9.3 ± 1.2 at Day 10 (mean ± SE, p
Electron densities in the upper ionosphere of Mars from the excitation of electron plasma oscillations

[1] In addition to remote radio sounding of the ionosphere of Mars, the MARSIS (Mars Advanced Radar for Subsurface and Ionospheric Sounding) instrument on the Mars Express spacecraft is also able to measure the in situ electron density from the excitation of local electron plasma oscillations. This paper presents an investigation of the electron density in the upper ionosphere of Mars based on the frequency of these oscillations. The advantage of this method is that electron densities can be measured at much higher altitudes than can be determined from remote radio soundings. Using this technique electron densities from 503 orbits have been analyzed over the period from 4 August 2005 to 31 July 2007 for altitudes ranging from about 275 to 1300 km. Although there is considerable variability from orbit to orbit, the median electron density at a given solar zenith angle (SZA) on the dayside of Mars decreases systematically with increasing altitude with a characteristic plasma scale height varying from about 80 to 145 km. At a fixed altitude, the electron density remains almost constant for SZAs less than about 80°. For SZAs greater than about 80° the electron density decreases rapidly with increasing SZA, approaching very low values on the nightside. Simulations performed using both magnetohydrodynamic and hybrid codes show that the nearly constant density at a given altitude is caused by the horizontal transport of plasma from the dayside toward the nightside due to interaction with the solar wind.
Active–sterile neutrino conversion: consequences for the r-process and supernova neutrino detection

Abstract We examine active–sterile neutrino conversion in the late time post-core-bounce supernova environment. By including the effect of feedback on the Mikheyev–Smirnov–Wolfenstein (MSW) conversion potential, we obtain a large range of neutrino mixing parameters which produce a favorable environment for the r-process. We look at the signature of this effect in the current generation of neutrino detectors now coming on line. We also investigate the impact of the neutrino–neutrino forward-scattering-induced potential on the MSW conversion.
New compounds: Reissert Compound Studies XXXII: Facile Synthesis of 3-azapapaverine

6,7-Dimethoxyphthalazine was obtained in four steps from veratric acid and converted to its Reissert compound. Alkylation of this Reissert compound with 3,4-dimethoxybenzyl chloride followed by hydrolysis gave 3-azapapaverine.
The Staphylococcus aureus Receptor for Fibronectin

The Staphylococcus aureus binding site for human fibronectin was determined by unique biologic assays based upon the specific adherence of the bacterium to nasal epithelial cells. Fibronectin treatment of S. aureus caused a reduction in adherence tallies on high granular and fully keratinized cells compared to controls ( p p S. aureus . Only ribitol teichoic acid had this property. Furthermore, fibronectin could neutralize the adherence- blocking ability of teichoic acid, which affects keratinized cells. Thus, teichoic acid seems to be a receptor for fibronectin.
Amniotic fluid glycine-valine ratio and neonatal morbidity in fetal growth restriction.

Objective: To test the hypothesis that an elevated amniotic fluid glycine-valine ratio predicts neonatal morbidity in growth-restricted newborns. Methods: Amniotic fluid (AF) was collected from 122 third-trimester pregnancies (range 31–39 weeks), 49 of which were complicated by fetal growth restriction. Amino acid analysis was performed by high-pressure liquid chromatography. Glycine-valine ratios were compared between normal and growth-restricted fetuses. Neonatal morbidity within the group of growth-restricted fetuses was characterized by evaluation of neonatal hypoglycemia, arterial cord blood gas analysis, and birth weight percentile. We also examined the correlation of AF glycine-valine ratio to the umbilical artery resistance index. The median interval between AF sampling and delivery was 1 day (range 0–8 days). Analyses were performed by Student t test, χ2 with Yates correction, or simple correlation when appropriate. P < .05 was considered significant. Results: Growth-restricted fetuses have a significantly elevated AF glycine-valine ratio compared with control subjects (3.31 ± 1.06 versus 2.61 ± 0.77, respectively, P < .001). There was no association of the glycine-valine ratio with gestational age for either group. An elevated glycine-valine ratio was not associated with neonatal hypoglycemia within the growth-restricted group (hypoglycemia: [n = 16] 3.19 ± 1.07; no hypoglycemia: (n = 30) 3.44 ± 1.09). There were no significant correlations of glycine-valine ratio with arterial cord blood pH (r = −0.10), oxygen pressure (r = 0.04), or base deficit (r = 0.12). There were no significant correlations of glycine-valine ratio and birth weight percentile (r = −.24) or umbilical artery resistance index (r = −.14). Conclusion: Amniotic fluid glycine-valine ratio is elevated in growth-restricted fetuses compared with control fetuses. However, the level of glycine-valine elevation is not associated with neonatal morbidity related to hypoglycemia, arterial cord blood gas abnormalities, or birth weight percentile.
Resonance Capture in Unbalanced Dual-Spin Spacecraft

Abstract : This study examines the spinup dynamics of dual-spin spacecraft having an imbalanced rotor. Of particular interest is a phenomenon called 'resonance capture' during which the spinup motor torque induces uncontrolled growth of nutation. A captured spacecraft tumbles end-over-end, while an escaped spacecraft experiences little nutation growth. The conditions which lead to both state are analyzed. A set of criteria based on the spacecraft's kinetic energy at the of spinup is used to determine whether or not it has been captured. To calculate the final energies against which these criteria are compared, a set of nondimensional equations of motion are numerically integrated. Using computer simulations, magnitude of the motor torque is shown to affect the probability of capture. For prolate spinup, larger torques are desirable, whereas for oblate spinup, smaller torques are preferred. This probability is also influenced by the initial spin configuration and is determine here as a function of the initial energies. For a given motor torque, some initial energies lead to guaranteed capture and others to guaranteed escape. This information is combined to form a 'map' which allows designers to find the best initial spinup conditions for a given spacecraft.
Di-jet correlation in Au+Au and Cu+Cu Collisions from PHENIX

PHENIX has measured the two-particle azimuth correlation in Au+Au at √s=200 GeV. Jet shape and yield at the away side are found to be strongly modified at intermediate and low pT, and the modifications vary dramatically with pT and centrality. At high pT, away side jet peak reappears but the yield is suppressed. Similar jet strength is found for Au+Au and Cu+Cu collisions with similar number of participant nucleons.
Carbenoid type base induced ring expansion of the adducts of cyclic ketones with bis(phenylthio)methyllithium

In another application of the principle that metallo derivatives of bis(phenylthio)acetals behave as carbenoids when present in the same molecule with another anionic group, the adducts of cyclic ketones with bis(phenylthio)methyllithium react with an alkyllithium to yield the ring expanded α-(phenylthio) ketones.
Stability-Boundary Approximations for Relay-Control Systems Via a Steepest-Ascent Construction of Lyapunov Functions

This paper presents a new technique for constructing Lyapunov functions for estimating the domain of asymptotic stability of nonlinear control systems. A machine program assigns figures of merit (based on the quality of the stability-boundary estimates) to the members of a set of Lyapunov functions and then searches for the one which maximizes this measure. The method is applied to relay-control systems, which are not tractable by other systematic techniques such as the method of Zubov. The paper is divided into two parts. The first part contains a discussion of the motions of relay-control systems and the technique of investigating their stability domains with Lyapunov functions. The second part contains a discussion of existing methods of generating Lyapunov functions and a description of the new method, along with a number of second and third-order examples.
The quintic NLS as the mean field limit of a boson gas with three-body interactions

We investigate the dynamics of a boson gas with three-body interactions in dimensions d=1,2. We prove that in the limit of infinite particle number, the BBGKY hierarchy of k-particle marginals converges to a limiting (Gross–Pitaevskii (GP)) hierarchy for which we prove existence and uniqueness of solutions. Factorized solutions of the GP hierarchy are shown to be determined by solutions of a quintic nonlinear Schrodinger equation. Our proof is based on, and extends, methods of Erdos–Schlein–Yau, Klainerman–Machedon, and Kirkpatrick–Schlein–Staffilani.
Practical Synthesis of 1-(7-Fluoro-naphthalen-1-yl)piperazine Hydrochloride

Abstract A practical and scalable preparation of 1-(7-fluoronaphthalen-1-yl)-piperazine hydrochloride (1) is reported. The original route for the synthesis of this compound involved the use of 1-amino-7-fluoronaphthalene and bis(2-chloroethyl)amine hydrochloride, two highly toxic compounds. A new protocol has been developed that employs a palladium-catalyzed Buchwald–Hartwig cross-coupling reaction between 1-Boc-piperazine and 1-bromo-7-fluoronaphthalene followed by piperazine deprotection with HCl gas. In addition, an efficient palladium removal protocol allowed for the preparation of the target molecule with less than 20 ppm of this metal. This methodology has been successfully implemented to produce multigram quantities of 1 with excellent purity and low palladium content.
Mandatory Arbitration and Civil Litigation: An Empirical Study of Medical Malpractice Litigation in the West

This article looks at the effect that pretrial, statutorily required screening panels in Nevada have had on medical malpractice litigation. I use two unique data sets on litigation in Nevada and neighboring states from 1983--88, during which the Nevada legislature enacted screening panels. Applying time-series and difference-in-difference analyses, I show that observed decreases in Nevada with respect to damage awards, attorney's fees, and duration in litigation reflected a broader secular trend. The panels did, however, reduce the relative probability of claims requiring resolution by the Nevada courts. Copyright 2004, Oxford University Press.
Analytical Studies on Static Aeroelastic Behavior of Forward-Swept Composite Wing Structures

An exact methodology allowing one to determine the aeroelastic lift distribution and the divergence instability of swept cantilevered composite wing structures is developed in this paper. The approach based on the Laplace transform technique enables one to solve, in a unified manner, both aeroelastic problems. The analysis encompasses the cases of free and constrained warping models for the wing twist. Numerical results are presented to demonstrate the effects played by the fiber orientation, ply lay-up, warping inhibition, and wing geometry on the subcritical static aeroelastic response and on the divergence instability of composite swept wings.
A Modular Safety Interlock System for High Energy Physics Experiments

A frequent problem in electronics systems for high energy physics experiments is to provide protection for personnel and equipment. Interlock systems are typically designed as an afterthought and as a result, the working environment around complex experiments with many independent high voltages or hazardous gas subsystems, and many different kinds of people involved, can be particularly dangerous. A set of modular hardware has been designed which makes possible a standardized, integrated, hierarchical system's approach and which can be easily tailored to custom requirements.
Improving the ability to predict mortality among burn patients

Background: Early efforts to predict death following severe burns focused on age and burn size; more recent work incorporated inhalation injury and pneumonia. Gender, co-morbid illness, and co-existent trauma have been implicated in burn mortality but have rarely been incorporated into predictive models. Methods: The National Burn Repository (NBR) and the National Trauma Data Bank (NTDB) provided data on 68,661 (54,219 and 14,442, respectively) burn patients that was used to develop and validate, respectively, a predictive model of burn mortality. Logistic regression was used to model the odds of mortality with respect to age, gender, % body surface area burned (BSAB), co-existent trauma, inhalation injury, pneumonia, and co-morbid illness. Performance of the predictive model was assessed using a deviance statistic, receiver operating characteristic (ROC) curves, and the Hosmer-Lemeshow (HL) statistic. Results: The predictive model that demonstrated optimal performance included the variables age, percent total BSAB, inhalation injury, co-existent trauma, and pneumonia. The area under the ROC curve for this model was 0.94 and the HL statistic was 16.0. The inclusion of additional variables, i.e., gender, co-morbid illness, did not improve the performance of the model despite reduction in the model deviance. When the predictive model was applied to the validation data source, the area under the ROC curve was 0.87 and the HL statistic was 10.0, indicating good discrimination and calibration. Conclusion: The results of this study suggest that a comprehensive predictive model of burn mortality incorporating certain variables not previously considered in other models provides superior predictive ability.
Piecewise constant prediction

Minimax prediction of binary sequences is investigated for cases in which the predictor is forced to issue a piecewise constant prediction. The minimax strategy is characterized for Hamming loss whereas, for logarithmic loss, an asymptotically minimax strategy which achieves the leading term of the asymptotic minimax redundancy, is proposed. The average redundancy case is also analyzed for i.i.d. distributions. The piecewise constant prediction paradigm may be of relevance to resource constrained settings.
Enantioselective total synthesis of (+)-amphidinolide t1.

An enantioselective first total syntheis of amphidinolide T1 (1) is described. Amphidinolide T1 (1), a 19-membered macrolide isolated from Amphidinium sp., has shown potent antitumor properties against a variety of NCI tumor cell lines. The synthesis is convergent and involves the assembly of C1−C10 segment 2 and C11−C21 segment 3 by an oxocarbenium ion-mediated alkylation and Yamaguchi macrolactonization sequence. The synthesis of fragment 2 involves an efficient cross metathesis and hydrogenation sequence between the terminal olefins of 5 and 6 to form the C4−C5 carbon−carbon bond. Enol ether 4 is designed to be the surrogate of fragment 3 where the sensitive C16-exo-methylene and the C13-hydroxyl group were protected as the bromoether derivative during the Lewis acid-catalyzed alkylation process. Both stereocenters in fragment 5 as well as the C2 and C3 stereocenters in fragment 4 are accessed by a highly diastereoselective ester-derived titanium enolate-mediated syn-aldol reaction. The bromoether deri...
Regional and Global Alliance Network Structures of Triad Multinational Enterprises

This study analyzes the structure of regional and global alli‐ance networks of multinationals. It examines the network structure of 172 Triad (U.S., Western European, and Japanese) multinationals during 2001‐2003 and how it affects subsequent corporate performance during 2004‐2006. We study a framework of regional/global strategies based on the social network view of relational ties among firms. Thus, we offer a new perspective to the growing literatures on the regional/global strategies and internationalization of alliance networks.
Improvements in children’s health: Does inequality matter?

The literature on the contributions to poverty reduction of average improvements in living standards vs. distributional changes uses only one measure of well-being – income or expenditure. Given that poverty is defined by deprivation over different dimensions, we explore the role of average improvements and distributional changes in children’s health and nutrition using the height of young children as our measure of well-being. Similar to the income literature, we find that shifts in the mean level of heights, not changes in distribution, account for most improvements in heights. Unlike the literature on income inequality, however, there is a positive association between improvements in average heights and reduced dispersion of those heights.
Interpolating implicit surfaces from scattered surface data using compactly supported radial basis functions

We describe algebraic methods for creating implicit surfaces using linear combinations of radial basis interpolants to form complex models from scattered surface points. Shapes with arbitrary topology are easily represented without the usual interpolation or aliasing errors arising from discrete sampling. These methods were first applied to implicit surfaces by Savchenko, et al. and later developed independently by Turk and O'Brien as a means of performing shape interpolation. Earlier approaches were limited as a modeling mechanism because of the order of the computational complexity involved. We explore and extend these implicit interpolating methods to make them suitable for systems of large numbers of scattered surface points by using compactly supported radial basis interpolants. The use of compactly supported elements generates a sparse solution space, reducing the computational complexity and making the technique practical for large models. The local nature of compactly supported radial basis functions permits the use of computational techniques and data structures such as k-d trees for spatial subdivision, promoting fast solvers and methods to divide and conquer many of the subproblems associated with these methods. Moreover, the representation of complex models permits the exploration of diverse surface geometry. This reduction in computational complexity enables the application of these methods to the study of shape properties of large complex shapes.
Iterative methods for design sensitivity analysis

A numerical method is presented for design sensitivity analysis, using an iterative-method reanalysis of the structure generated by a small perturbation in the design variable; a forward-difference scheme is then employed to obtain the approximate sensitivity. Algorithms are developed for displacement and stress sensitivity, as well as for eignevalues and eigenvector sensitivity, and the iterative schemes are modified so that the coefficient matrices are constant and therefore decomposed only once.
Risk Management and Optimal Pricing in Online Storage Grids

Online storage service providers grant a way for companies to avoid spending resources on maintaining their own in-house storage infrastructure and thereby allowing them to focus on their core business activities. These providers, however, follow a fixed, posted pricing strategy that charges the same price in each time period and thus bear all the risk arising out of demand uncertainties faced by their client companies. We examine the effects of providing a spot market with dynamic prices and forward contracts to hedge against future revenue uncertainty. We derive revenue-maximizing spot and forward prices for a single seller facing a known set of buyers. We perform a simulation study using publicly available traffic data regarding Amazon S3 clients from Alexa.com to validate our analytical results. Our field study supports our analysis and indicates that spot markets alone can enhance revenues to Amazon, but this comes at the cost of increased risks due to the increased market share in the spot markets. Furthermore, adding a forward contract feature to the spot markets can reduce risks while still providing the benefits of enhanced revenues. Although the buyers incur an increase in costs in the spot market, adding a forward contract does not cause any additional cost increase while transferring the risk to the buyers. Thus, storage grid providers can greatly benefit by applying a forward contract alongside the spot market.
Intersections of arithmetic Hirzebruch-Zagier cycles

We establish a close connection between the intersection multiplicities of three arithmetic Hirzebruch–Zagier cycles and the Fourier coefficients of the derivative of a certain Siegel–Eisenstein series at its center of symmetry. Our main result proves a conjecture of Kudla and Rapoport.
Construction of self-adjoint Berezin–Toeplitz operators on Kähler manifolds and a probabilistic representation of the associated semigroups

Abstract We investigate a class of operators resulting from a quantization scheme attributed to Berezin. These so-called Berezin–Toeplitz operators are defined on a Hilbert space of square-integrable holomorphic sections in a line bundle over the classical phase space. As a first goal we develop self-adjointness criteria for Berezin–Toeplitz operators defined via quadratic forms. Then, following a concept of Daubechies and Klauder, the semigroups generated by these operators may under certain conditions be represented in the form of Wiener-regularized path integrals. More explicitly, the integration is taken over Brownian motion paths in phase space in the ultra-diffusive limit. All results are the consequence of a relation between Berezin–Toeplitz operators and Schrodinger operators defined via certain quadratic forms. The probabilistic representation is derived in conjunction with a version of the Feynman–Kac formula.
Interpretation of precision measurements in the strongly interacting limit of the standard electroweak model

Abstract Strong rescattering corrections to one-loop contributions to the parameters of the standard electroweak model are considered.
Carbonyl group stabilization of radicals: Solvent effects on azoalkane decomposition

Abstract The synthesis and rates of decomposition of bis(1,1-dimethyl-2-oxopropyl) diazene (2p) are described. A series of substituted azoalkanes is compared to four other systems measuring radical substituent effects. These correlations and a solvent polarity study indicate the lack of polar contributions in azo decompositions.
High-Redshift HCN Emission: Dense Star-forming Molecular Gas in IRAS F10214+4724

Hydrogen cyanide emission in the J = 1–0 transition has been detected at redshift z = 2.2858 in IRAS F10214+4724 using the Green Bank Telescope. This is the second detection of HCN emission at high redshift. The large HCN line luminosity in F10214 is similar to that in the Cloverleaf (z = 2.6) and the ultraluminous infrared galaxies Mrk 231 and Arp 220. This is also true of the ratio of HCN to CO luminosities. The ratio of far-infrared luminosity to HCN luminosity, an indicator of the star formation rate per solar mass of dense gas, follows the correlation found for normal spirals and infrared luminous starburst galaxies. F10214 clearly contains a starburst that contributes, together with its embedded quasar, to its overall infrared luminosity. A new technique for removing spectral baselines in the search for weak, broad emission lines is presented.
The Star Formation Rate-Dense Gas Relation in the Nuclei of Nearby Galaxies

We investigate the relationship between the star formation rate (SFR) and dense molecular gas mass in the nuclei of galaxies. To do this, we utilize the observed 850 μm luminosity as a proxy for the infrared luminosity (LIR) and SFR, and we correlate this with the observed CO(J = 3–2) luminosity. We find tentative evidence that the LIR-CO(J = 3–2) index is similar to the Kennicutt-Schmidt (KS) index (N ≈ 1.5) in the central ~1.7 kpc of galaxies, and it flattens to a roughly linear index when including emission from the entire galaxy. This result may imply that the volumetric Schmidt relation is the underlying driver behind the observed SFR-dense gas correlations, and it provides tentative confirmation for recent numerical models. While the data exclude the possibility of a constant LIR-CO(J = 3–2) index for both galaxy nuclei and global measurements at the ~80% confidence level, the considerable error bars cannot preclude alternative interpretations.
Activation-dependent internalization of the human prostacyclin receptor.

Prostacyclin (PGI2), the major cyclooxygenase-derived arachidonic acid metabolite formed in macrovascular endothelial cells’, is a potent vasodilator, an inhibitor of platelet aggregation2 and smooth muscle proliferation3 in vitro and an antithrombotic in mice4. Given the absence of PGI2 antagonists its role in the prevention of vascular disease in vivo has remained speculative.
Rate Coefficients for D(1s) + H+ ⇆ D+ + H(1s) Charge Transfer and Some Astrophysical Implications

We have calculated the rate coefficients for D(1s) + H+ D+ + H(1s) using recently published theoretical cross sections. We present results for temperatures T from 1 K up to 2 × 105 K and provide fits to our data for use in plasma modeling. Our calculations are in good agreement with previously published rate coefficients for 25 ≤ T ≤ 300 K, which covers most of the limited range for which those results were given. Our new rate coefficients for T 100 K are significantly larger than the values most commonly used for modeling the chemistry of the early universe and of molecular clouds. This may have important implications for the predicted HD abundance in these environments. Using our results, we have modeled the ionization balance in high-redshift QSO absorbers. We find that the new rate coefficients decrease the inferred D/H ratio by 0.4%. This is a factor of 25 smaller than the current 10% uncertainties in QSO absorber D/H measurements.
Manifestations of Top Compositeness at Colliders

We explore the possibility that the right-handed top quark is composite, identifying possible signatures of compositeness and how they might manifest themselves at the LHC and Tevatron. We perform a complete analysis of the dimension six modifications of the top coupling to gluons and find that cancellations among operators in the t rate allow for very low compositeness scales, but this can be drastically improved by looking at kinematic distributions. Turning to the LHC, we examine four top production from a dimension six four-top operator and estimate the LHC with 100 fb−1 collected luminosity to be sensitive to compositeness scales as high as 5 TeV.
Timing of Reproduction by Predatory Stinkbugs (Hemiptera: Pentatomidae): Patterns and Consequences for a Generalist and a Specialist

The seasonal timing of reproduction was examined for two predatory stinkbugs (He- miptera: Pentatomidae) in stands of goldenrod (Solidago spp.) near Ithaca, New York, USA. One species, Perillus circumcinctus, is a specialist predator of soft-bodied beetle larvae and occurs in few habitats. The second species, Podisus maculiventris, is a generalist predator that attacks many kinds of insect prey in a great diversity of habitats. In goldenrod stands both predators fed primarily on Trirhabda spp. (Coleoptera: Chrysomelidae). Sweep samples revealed that nymphs of the specialist predator matured in synchrony with larvae of the univoltine Trirhabda in May and June. Most nymphs of the generalist predator matured several weeks later and older instars of this predator fed primarily on Trirhabda adults. Nymphs of both predators easily overpower larvae of Trirhabda, but they rarely succeed in capturing the alert beetle adults; consequently the availability of food in goldenrod stands deteriorates as the beetles mature. Field patterns of body size of the predators reflect the seasonal change in food supply. For both predators, adult body size depends upon the rate at which nymphs consume prey. As the season progressed, the size of newly molted adults of both stinkbugs declined, paralleling the earlier decline in availability of Trirhabda larvae as prey for nymphs. Because of differences in seasonal appearance, most specialist predators attained adult sizes in the field approximating the maxima attained in the laboratory, while most generalist predators attained significantly smaller sizes. Those few generalist predators that did mature early also generally attained maximum size; they experienced little difficulty finding, capturing, and digesting Trirhabda larvae. These results indicate that the specialist predator exploits Trirhabda populations more effectively than the generalist. The key difference in the habits of the two predators lies not in the foraging efficiency of nymphs nor in biochemical adaptation to the prey, but rather in timing of reproduction. Well-timed oviposition in goldenrod stands by specialist females ensures that offspring mature during the short period each summer when prey are easily harvested. In contrast, the relatively poor timing of oviposition by generalist females results in most of their offspring experiencing substantial food stress.
Real-time performance modeling for adaptive software systems

Modern, adaptive software systems must often adjust or reconfigure their architecture in order to respond to continuous changes in their execution environment. Efficient autonomic control in such systems is highly dependent on the accuracy of their representative performance model. In this paper, we are concerned with real-time estimation of a performance model for adaptive software systems that process multiple classes of transactional workload. Based on an open queueing network model and an Extended Kalman Filter (EKF), experiments in this work show that: 1) the model parameter estimates converge to the actual value very slowly when the variation in incoming workload is very low, 2) the estimates fail to converge quickly to the new value when there is a step-change caused by adaptive reconfiguration of the actual software parameters. We therefore propose a modified EKF design in which the measurement model is augmented with a set of constraints based on past measurement values. Experiments demonstrate the effectiveness of our approach that leads to significant improvement in convergence in the two cases.
Targeting, cascading and indirect tax design

Purpose – The purpose of this paper is to address two fundamental issues in indirect tax design. It first revisits the case for reduced rates on items especially important to the poor, and then explores the welfare costs from cascading taxes. Design/methodology/approach – Applied theory was used in this paper. Findings – On the first issue, the paper establishes conditions under which even very crudely targeted spending measures better serve the interests of the poor than does the reduced taxation of particular commodities looming large in their consumption. On the second, it shows that these may actually be lower the wider the set of inputs that are taxed but, more to the point, may plausibly be large even at a low nominal tax rate and with relatively few stages of production: contrary to a common mantra, “a low rate on a broad base” is not always good policy. Originality/value – Both issues addressed in the paper are recurrent and central concerns in the design of indirect taxes in general, and the valu...
Mission analysis techniques for attached Shuttle payloads

Visibility times, i.e., times at which desired targets are visible to a payload, are examined for attached Shuttle payloads. These times are affected by a number of constraints. Some constraints are examined along with mathematical or computer modeling techniques used to determine their effects. The constraints include oc- culation of the Earth, moon, and Sun, and limb avoidance angles of these bodies; orbit parameters such as inclination and ascending node, along with sensitivity to changes in these parameters; tracking and data relay satellite system acquisition; South Atlantic anomaly avoidance, nighttime viewing only; bright Earth avoidance angles; the field of view; Shuttle attitude; and Orbiter operational constraints. All of this information is in- tegrated and, with computer programs, a schedule of observations and Shuttle attitudes is obtained. ITH the advent of the Shuttle, new opportunities have opened up for flying payloads into space. In particular, the former sounding rocket user can look forward to in- creased time in space, from a few minutes to possibly many hours or days. He might also find lower costs since a sounding rocket is expendable, where an experiment container onboard the Shuttle is not. There are many factors involved which must be taken into account by the new user flying a payload onboard the Shuttle. Some factors which affect the ob- servation of desired targets are discussed in this paper as well as the mathematical formulation or computer modeling of each of these factors. This is not an exhaustive list, only currently typical. The purpose in presenting them here is twofold: 1) to make the experimenter flying a payload on the Shuttle first aware that there are constraints affecting the amount of visible time of his desired targets and, then, what some of these constraints are and how to determine their effect; and 2) to present at least an overview of these com- puter modeling or mathematical techniques in a common arena—the context of mission analysis techniques for at- tached Shuttle payloads. Figure 1 shows the target/visibility scenario graphically. Among the targets considered are the stars, planets, sun, moon, tracking and data relay satellite (TDRS), and points or areas of the Earth's surface. Many of the examples and much of the results presented here were taken from a study done for NASA's Office of Space Science-3 (OSS-3) mission. This uses a Shuttle pallet with three experiments mounted on a pointing system. Not all experiments flying on the Shuttle, particularly the sounding rocket type, will have their own pointing system. Nor may the experimenter have any say in Shuttle attitude or orbital characteristics. The reader should be aware of this and note that not all the information in this paper may apply to him, but he should extract what does affect his particular situation.
New One-Step Synthesis of Isonitriles

Abstract A new one-step synthesis of isonitriles is described. The starting materials are a primary amine, chloroform, sodium hydride, and the phase-transfer catalyst 15-crown-5 ether, and the solvent is benzene. Five compounds are used to illustrate the features of the new synthesis: 1-adamantyl isocyanide (2a), 2-adamantyl isocyanide (2b), cis-1,8-diisocyano-p-menthane (2c), 2,4,6-trimethylphenyl isocyanide (2d), and trityl isocyanide (2e). The present synthesis is superior to the existing published syntheses because of its yields are good, the by-products are innocuous (H2 gas and NaCl), and its workup is simple. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.
Invariant Finite Element Model for Composite Structures: The Generalized Unified Formulation

The generalized unified formulation presented here is a modern approach for the finite element analysis of sandwich plates and in general multilayered structures. A large variety of types of theories with any combination of orders of expansion for the different displacement variables can be obtained from the expansion of six 1 x 1 arrays (the kernels or fundamental nuclei of the generalized unified formulation). Each of the displacement variables is independently treated and different orders of expansions for the different unknowns can be chosen. Because infinite combinations can be freely chosen for the displacements, the generalized unified formulation allows the user to write ∞ 3 higher-order shear deformation theories, ∞ 3 zig-zag theories, and ∞ 3 layerwise theories with a single invariant formulation implemented in a single finite element method code. The six independent fundamental nuclei are formally invariant with respect to the order used for the expansion or with respect to the type of theory. The generalized unified formulation can be also adopted for mixed variational statements. In such cases the number of independent kernels would be different but their size would still be 1 x 1 arrays. This paper assesses bending of sandwich structures. Analytical and elasticity solution are compared. The effect of the zig-zag form of the displacement is discussed.
Compensating tune spread induced by space charge in bunched beams

The effects of space charge play a significant role in modern-day accelerators, frequently constraining the beam parameters attainable in an accelerator or in an accelerator chain. They also can limit the luminosity of hadron colliders operating either at low energies or with sub-TeV high-brightness hadron beams. The latter is applied for strongly cooled proton and ion beams in eRHIC---the proposed future electron-ion collider at Brookhaven National Laboratory. Several schemes were proposed to compensate for space-charge effects in a coasting (e.g., continuous) hadron beam, and some have been tested. Using an appropriate transverse profile of the electron beam (or plasma column) for a coasting beam would compensate both the tune shift and the tune spread in the hadron beam. But none of these methods address the issue of compensating space-charge induced tune spread in a bunched hadron beam, i.e., the dependence of the particle's tune shift on its longitudinal position inside the bunch. In this paper we propose and evaluate a novel idea of using a copropagating electron bunch with mismatched longitudinal velocity to compensate the space-charge induced tune shift and tune spread. We present several practical examples of such a system.
Ribozyme-based insulator parts buffer synthetic circuits from genetic context

Lou et al. find that sequences between promoters and regulated genes in synthetic circuits cause unpredictable gene expression, and they identify and characterize insulator parts that cleave untranslated regions present in circuits to overcome this problem.