cssi/SciSciGPT-SciSciNet huggingface dataset:
An Accurate Re-formulation of the Wigner Function Method for Quantum Transport Modeling

The Wigner function is a promising method for including such effects as time dependence, self consistency, and inelastic scattering in quantum transport calculations, However, issues regarding the accuracy and consistency of the method need to be resolved. This paper presents a numerical method for determining the Wigner function which is derived from an accurate discretization of the Schrodinger equation. All of the density matrix information is preserved in this method, rather than half, as in previous methods. Results of self-consistent calculations under low bias conditions are presented. Further work must be done on the proper formulation of scattering rates and to determine the device dimensions and k-space discretizations that are required for realistic quantum device calculations.
Null sets of harmonic measure on NTA domains: Lipschitz approximation revisited

We show the David–Jerison construction of big pieces of Lipschitz graphs inside a corkscrew domain does not require surface measure be upper Ahlfors regular. Thus we can study absolute continuity of harmonic measure and surface measure on NTA domains of locally finite perimeter using Lipschitz approximations. A partial analogue of the F. and M. Riesz Theorem for simply connected planar domains is obtained for NTA domains in space. As one consequence every Wolff snowflake has infinite surface measure.
Muon /g-2, dark matter detection and accelerator physics

Abstract We examine the recently observed deviation of the muon g −2 from the Standard Model prediction within the framework of gravity mediated SUGRA models with R-parity invariance. Universal soft breaking (mSUGRA) models, and models with nonuniversal Higgs and third generation squark/slepton masses at M G are considered. All relic density constraints from stau–neutralino co-annihilation and large tan β NLO corrections for b → sγ decay are included, and we consider two possibilities for the light Higgs: m h >114 GeV and m h >120 GeV. The combined m h , b → sγ and a μ bounds give rise to lower bounds on tan β and m 1/2 , while the lower bound on a μ gives rise to an upper bounds on m 1/2 . These bounds are sensitive to A 0 , e.g., for m h >114 GeV, the 95% C.L. is tan β >7(5) for A 0 =0(−4 m 1/2 ), and for m h >120 GeV, tan β >15(10). The positive sign of the a μ deviation implies μ >0, eliminating the extreme cancellations in the dark matter neutralino–proton detection cross section so that almost all the SUSY parameter space should be accessible to future planned detectors. Most of the allowed parts of parameter space occur in the co-annihilation region where m 0 is strongly correlated with m 1/2 . The lower bound on a μ then greatly reduces the allowed parameter space. Thus using 90% C.L. bounds on a μ we find for A 0 =0 that tan β ⩾10 and for tan β ⩽40 that m 1/2 =(290–550) GeV and m 0 =(70–300) GeV. Then the tri-lepton signal and other SUSY signals would be beyond the Tevatron Run II (except for the light Higgs), only the τ 1 and h and (and for part of the parameter space) the e 1 will be accessible to a 500 GeV NLC, while the LHC would be able to see the full SUSY mass spectrum.
BENCHMARK TESTS FOR MARKOV CHAIN MONTE CARLO FITTING OF EXOPLANET ECLIPSE OBSERVATIONS

Ground-based observations of exoplanet eclipses provide important clues to the planets' atmospheric physics, yet systematics in light curve analyses are not fully understood. It is unknown if measurements suggesting near-infrared flux densities brighter than models predict are real, or artifacts of the analysis processes. We created a large suite of model light curves, using both synthetic and real noise, and tested the common process of light curve modeling and parameter optimization with a Markov Chain Monte Carlo algorithm. With synthetic white noise models, we find that input eclipse signals are generally recovered within 10% accuracy for eclipse depths greater than the noise amplitude, and to smaller depths for higher sampling rates and longer baselines. Red noise models see greater discrepancies between input and measured eclipse signals, often biased in one direction. Finally, we find that in real data, systematic biases result even with a complex model to account for trends, and significant false eclipse signals may appear in a non-Gaussian distribution. To quantify the bias and validate an eclipse measurement, we compare both the planet-hosting star and several of its neighbors to a separately chosen control sample of field stars. Re-examining the Rogers et al. Ks-band measurement of CoRoT-1b finds an eclipse ppm deep centered at me = . Finally, we provide and recommend the use of selected data sets we generated as a benchmark test for eclipse modeling and analysis routines, and propose criteria to verify eclipse detections.
The pinene path to taxol: Readily accessible a-ring building blocks based on novel alkyl- and alkenyllithium reagents with internal carbonyl groups

Abstract The synthesis and chemistry of the novel reagents and stereochemically defined taxane A-ring building blocks 7e–9e are described, providing the basis for the solution to problems previously encountered in the development of syntheses of taxol and its analogs based on pinene.
Catalytic Reactions of Carbene Precursors on Bulk Gold Metal

Bulk gold metal powder, consisting of particles (5−50 μm) much larger than nanoparticles, catalyzes the coupling of carbenes generated from diazoalkanes (R2C═N2) and 3,3-diphenylcyclopropene (DPCP) to form olefins. It also catalyzes cyclopropanation reactions of these carbene precursors with styrenes. The catalytic activity of the gold powder depends on the nature of the gold particles, as determined by TEM and SEM studies. The reactions can be understood in terms of mechanisms that involve the generation of carbene R2C: intermediates adsorbed on the gold surface.
Comprehensive analysis of the chromatin landscape in Drosophila melanogaster

Chromatin is composed of DNA and a variety of modified histones and non-histone proteins, which have an impact on cell differentiation, gene regulation and other key cellular processes. Here we present a genome-wide chromatin landscape for Drosophila melanogaster based on eighteen histone modifications, summarized by nine prevalent combinatorial patterns. Integrative analysis with other data (non-histone chromatin proteins, DNase I hypersensitivity, GRO-Seq reads produced by engaged polymerase, short/long RNA products) reveals discrete characteristics of chromosomes, genes, regulatory elements and other functional domains. We find that active genes display distinct chromatin signatures that are correlated with disparate gene lengths, exon patterns, regulatory functions and genomic contexts. We also demonstrate a diversity of signatures among Polycomb targets that include a subset with paused polymerase. This systematic profiling and integrative analysis of chromatin signatures provides insights into how genomic elements are regulated, and will serve as a resource for future experimental investigations of genome structure and function.
On the quantization constraints for a D3-brane in the geometry of NS5-branes

A D3-brane in the background of NS5-branes is studied semi-classically. The conditions for preserved supersymmetry are derived, leading to a differential equation for the shape of the D3-brane. The solutions of this equation are analyzed. For a D3 brane intersecting the NS5-branes, the angle of approach is known to be restricted to discrete values. Four different ways to obtain this quantization are described. In particular, it is shown that, assuming the D3-brane avoids intersecting a single NS5 brane, the above discrete values correspond to the different possible positions of the D3-branes among the NS5-branes.
Transition dynamics of VTOL aircraft

Asymptotic approximations using multiple time scales are developed for the longitudinal dynamics of VTOL vehicles during the hover, forward-flight transition. After reviewing the method briefly, the transitional equations of motion whose coefficients vary with flight velocity are studied. Rapid and slow motions of the vehicle are extracted individually and combined to yield a composite solution. The time scales are necessarily nonlinear functions and complex quantities to describe nonautonomous phenomena. Aircraft in steady flight arise as a natural limit. The present method thus generalizes earlier time scale analyses. The technique is applied to VTOL vehicles exhibiting typical stability derivative variations, first to the two degree-of-freedom case and then the three degree-of-freedom case. The asymptotic approximations are compared with exact numerical integrals. An analytical description of the aircraft motion is thus obtained. The problem of transition points is outlined.
Optical processor for adaptive arrays

Abstract Two novel architectures for implementing the LMS algorithm optically are introduced. Convergence of the LMS algorithm is analyzed and the effect of the analog inaccuracies are considered.
Differential melt scaling for oblique impacts on terrestrial planets

Abstract Analytical estimates of melt volumes produced by a given projectile and contained in a given impact crater are derived as a function of impact velocity, impact angle, planetary gravity, target and projectile densities, and specific internal energy of melting. Applications to impact events and impact craters on the Earth, Moon, and Mars are demonstrated and discussed. The most probable oblique impact (45°) produces ∼1.6 times less melt volume than a vertical impact, and ∼1.6 and 3.7 times more melt volume than impacts with 30° and 15° trajectories, respectively. The melt volume for a particular crater diameter increases with planetary gravity, so a crater on Earth should have more melt than similar-size craters on Mars and the Moon. The melt volume for a particular projectile diameter does not depend on gravity, but has a strong dependence on impact velocity, so the melt generated by a given projectile on the Moon is significantly larger than on Mars. Higher surface temperatures and geothermal gradients increase melt production, as do lower energies of melting. Collectively, the results imply thinner central melt sheets and a smaller proportion of melt particles in impact breccias on the Moon and Mars than on Earth. These effects are illustrated in a comparison of the Chicxulub crater on Earth, linked to the Cretaceous–Tertiary mass extinction, Gusev crater on Mars, where the Mars Exploration Rover Spirit landed, and Tsiolkovsky crater on the Moon. The results are comparable to those obtained from field and spacecraft observations, other analytical expressions, and hydrocode simulations.
High gain free electron laser for heating and current drive in the ALCATOR-C tokamak

Abstract We have used the free electron laser particle simulation code FRED to examine the design of an FEL for amplifying radiation in the 1–2 mm wavelength range for use in electron heating and current drive in a tokamak device such as ALCATOR-C. We have used as a desired design goal a peak output power of 8 GW, with a minimum input power in the 1–100 W range. We have examined the effects of electron beam current, energy and brightness, laser frequency and input power as well as wiggler wavelength and overall wiggler length on performance of the FEL. We find that to obtain the desired power output, we require a 3 kA electron beam with a brightness of about 1 × 105 A/cm2. For a 1 mm wavelength system, the beam energy must be at least 10 MeV, the laser input power must be at least 100 W, and the wiggler wavelength is 8 cm, with an overall length of at least 6 m. For a 2 mm wavelength system, the output power goals can be met with a 7 MeV electron beam, with 10 W of input laser power, and a wiggler with an 8 cm wavelength and total length of at least 6 m. The beam and laser requirements to meet the design criteria are less stringent for the 2 mm wavelength system. The magnet requirements to meet the design power level goal is more difficult to meet with a wiggler wavelength of 8 cm compared to a 9.8 cm wiggler wavelength. With the 10 MeV beam energy of the 1 mm system and the 7 MeV beam energy of the 2 mm system, the peak magnetic field changes from about 0.4 to 0.6 T when the wiggler wavelength changes from 9.8 to 8 cm.
CHEMICAL REACTIVITY IN ORGANIZED MEDIA : STATISTICAL ENTROPY AND INFORMATION IN CRYSTALS AND ENZYMES

Abstract The control of chemical reactivity has been a subject of intense research activity for many years. It is known that supramolecular systems are capable of influencing the outcome of chemical reactions to levels not easily achieved by homogeneous liquids. Their influence is not always expressed through specific interactions that stabilize a transition state. Their role can be frequently ascribed to the structural pre-organization of the reactant towards particular chemical reactions. Because of this, systems as diverse as micelles, zeolites, enzymes and crystals are frequently referred to as organized media. Recent work on reactions in organized media may be analyzed with an intuitive model based on simple statistical entropy principles.
Phase structure for lattice fermions with flavored chemical potential terms

We discuss the chiral phase diagram in the parameter space of lattice QCD with minimal-doubling fermions, which can be seen as lattice fermions with flavored chemical potential terms. We study strong-coupling lattice QCD with the Karsten-Wilczek formulation, which has one relevant parameter μ 3 as well as gauge coupling and a mass parameter. We find a nontrivial chiral phase structure with a second-order phase transition between chiral symmetric and broken phases. To capture the whole structure of the phase diagram, we study the related lattice Gross-Neveu model. The result indicates that the chiral phase transition also exists in the weak-coupling region. From these results we speculate on the μ 3−g 2 chiral phase diagram in lattice QCD with minimal-doubling fermions, and discuss their application to numerical simulations.
Engine seal technology requirements to meet NASA's Advanced Subsonic Technology program goals

Cycle studies have shown the benefits of increasing engine pressure ratios and cycle temperatures to decrease engine weight and improve performance of commercial turbine engines. NASA is working with industry to define technology requirements of advanced engines and engine technology to meet the goals of NASA's Advanced Subsonic Technology Initiative. As engine operating conditions become more severe and customers demand lower operating costs, NASA and engine manufacturers are investigating methods of improving engine efficiency and reducing operating costs. A number of new technologies are being examined that will allow next generation engines to operate at higher pressures and temperatures. Improving seal performance - reducing leakage and increasing service life while operating under more demanding conditions - will play an important role in meeting overall program goals of reducing specific fuel consumption and ultimately reducing direct operating costs. This paper provides an overview of the Advanced Subsonic Technology program goals, discusses the motivation for advanced seal development, and highlights seal technology requirements to meet future engine performance goals.
Measurement of the refractive index and thermo-optic coefficient of water near 193 nm

We present accurate measurements of several important optical constants of high-purity water for wavelengths near 193.39 nm at 21.50°C: the absolute refractive index n = 1.436 62(2), the dispersion dn/dλ = −2.109(17)×10−3 nm−1, and the thermo-optic coefficient dn/dT = −1.00(4)×10−4 (°C)−1. We determine these values by two independent approaches, the minimum deviation prism method and an interferometric technique, and find that they give mutually consistent results.
Surveillance of colonization and infection with Staphylococcus aureus susceptible or resistant to methicillin in a community skilled-nursing facility.

Abstract Background: Methycillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen in acute care hospitals and long-term care facilities. New studies have been reported in private skilled nursing facilities (SNFs) not experiencing outbreaks of infections caused by MRSA. Methods: From a 149-bed SNF with no outbreaks, we report a 1-year prospective surveillance study of S. aureus colonization and infection, with focus on S. aureus phenotypes, both methicillin susceptible (MS) and methicillin resistant (MR). Nasal and stool or rectal screening cultures were done on admission, and all patients underent sceening of at least a quarterly basis for 1 year. Results: Overall, 35% of patients were colonized at least once with S. aureus , (72% MS, 25% MR, and 3% mixed phenotypes), 94% of the MRSA were ciprofloxacin resistant. Nasal colonization with any S. aureus was more frequent, but 13% of patients had positive results only in rectal specimens. Twenty-one percent of the newly admitted and 15% of continuing patients acquired colonization during their stay in the SNF. Colonization was transient or persistent, persisted longer in the nares compared with colonization in rectal specimens, and was more stable for methicillin-susceptible S. aureus . Nine percent of patients had development of infection with S. aureus . There was no indication that MRSA colonization led to more infections than methicillin-susceptible S. aureus . Of the 13 infected patients in whom cultures had previously been obtained, seven (54%) had been colonized by the same phenotype strains. Conclusions: In this private SNF, endemic S. aureus infections occur at a low frequency, reflecting a moderate level of colonization with S. aureus . However, a trend showing gradual increases in frequencies of colonization and infection is of concern and suggests that in this SNF, future intervention could become warranted.
High-temperature spectroscopy for nuclear waste applications

Instrumentation has been developed to perform uv-vis-nir absorbance measurements remotely and at elevated temperatures and pressures. Fiber-optic spectroscopy permits the interrogation of radioactive species within a glovebox enclosure at temperatures ranging from ambient to >100 °C. Spectral shifts as a function of metal-ligand coordination are used to compute thermodynamic free energies of reaction by matrix regression analysis. Pr3+ serves as a convenient analog for trivalent actinides without attendant radioactivity hazards, and recent results obtained from 20–95 °C with the Pr-acetate complexation system are presented. Preliminary experimentation on Am(III) hydrolysis is also described.
HERMES and the spin of the proton

HERMES is a second generation experiment to study the spin structure of the nucleon, in which measurements of the spin dependent properties of semi-inclusive deep-inelastic lepton scattering are emphasized. Data have been accumulated for semi-inclusive pion, kaon, and proton double-spin asymmetries, as well as for high-pT hadron pairs, and single-spin azimuthal asymmetries for pion electroproduction and deep virtual Compton scattering. These results provide information on the flavor decomposition of the polarized quark distributions in the nucleon and a first glimpse of the gluon polarization, while the observation of the azimuthal asymmetries show promise for probing the tensor spin of the nucleon and isolating the total angular momentum carried by the quarks.
Achievable information rates and the coding-spreading tradeoff in finite-sized synchronous CDMA systems

In this letter, we compute achievable information rates for finite-sized synchronous code-division multiple-access (CDMA) systems, and low-density parity-check (LDPC) codes are adopted to approach the achievable rates. The associated coding-spreading tradeoff problem is also considered using these results. We assume binary random spreading sequences, and the computed achievable rates are averaged over ensembles of spreading sequences. Unlike most prior papers, which analyze the spectral efficiency of large CDMA systems under Gaussianity assumptions (channel inputs and/or multiple-access interference), we make no such assumptions. In order to display the coding-spreading tradeoff, we plot the minimum required signal-to-noise ratio for reliable transmission as a function of information rate. It is shown that the coding-spreading tradeoff favors all coding (i.e., no spreading) when the optimal joint multiuser detector/decoder is employed, whereas for systems with a suboptimal multiuser detector and single-user decoders, there generally exists an optimal balance between coding and spreading. We also provide simulation results on the performance of LDPC-coded synchronous CDMA systems which approach the information-theoretic limits we have computed.
Return of the volcano: PHENIX azimuthal correlations 62.4 GeV Au+Au

As in previous analyses at √s NN =200 GeV., correlations in azimuthal angles between inclusive charge particles at intermediate transverse momentum (p T=1.0−4.0) GeV are studied at √s NN =62.4 GeV. The di-jet correlations reveal similar modification as in 200 GeV. Specifically large modification, including the “volcano” or “cone” structure, persists in the awayside correlation.
Four-Component Domino Reaction Leading to Multifunctionalized Quinazolines

A new four-component domino reaction has been discovered. The reaction is easy to perform simply by mixing four common reactants and K2CO3 in ethylene glycol under microwave irradiation. The reaction proceeds rapidly and can be finished within 10−24 min with water as the major byproduct, making workup convenient. Four stereogenic centers with one quaternary carbon−amino function are controlled very well; the stereochemistry was unequivocally determined by X-ray structural analysis. The resulting pyrido[3,4-i]quinazoline derivatives are of importance for organic and medicinal research.
Subnational fiscal behavior under the expectation of federal bailouts

This paper analyzes how subnational governments allocate own resources between current spending and infrastructure investment and decide on borrowing under the expectation of federal bailouts. It is assumed that states' borrowing possibilities increase with the expectation of such bailouts because the financial system is willing to fund a higher amount of public investment projects. As a result, state governments engage in an opportunistic behavior: they allocate a higher (lower) than optimal amount of own resources to current spending (infrastructure investment) and over‐borrow.
Finite T electroweak phase transition on the lattice

This talk reviews recent lattice results on the high T electroweak phase transition. A remarkably accurate picture emerges: a) the transition is of first order for mH ≲ 80 GeV and vanishes for larger mH; b) transition temperature, latent heat and interface tension are known, as well as c) the properties of the broken and symmetric phases. New developments in the sphaleron rate calculations are discussed.
Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships

We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy. These mass scaling relationships between line widths and luminosity are based on recently improved empirical relationships between the broad-line region size and luminosities in various energy bands and are calibrated to the improved mass measurements of nearby AGNs based on emission-line reverberation mapping. The mass scaling relationship based on the Hβ line luminosity allows mass estimates for low-redshift sources with strong contamination of the optical continuum luminosity by stellar or nonthermal emission, while that based on the C IV λ1549 line dispersion allows mass estimates in cases where only the line dispersion (as opposed to the FWHM) can be reliably determined. We estimate that the absolute uncertainties in masses given by these mass scaling relationships are typically around a factor of 4. We include in an appendix mass estimates for all of the Bright Quasar Survey (PG) quasars for which direct reverberation-based mass measurements are not available.
A computational strategy for making complicated structural problems simple

Abstract An effective computational strategy is presented for the analysis of large and complex structures. The strategy is based on generating the response of the complex structure using large perturbations from that of a lower-order (simpler) model associated with a simpler structure (or a simpler mathematical/discrete model of the original structure). The three key elements of the strategy are: (a) mixed (or primitive variable) formulation with the fundamental unknowns consisting of generalized displacements and stress parameters; (b) operator splitting, or a reduction method to relate the arrays and degrees of freedom of the original complex structure to those of the simpler system; and (c) efficient iterative process for the generation of the response of the complex structure starting from that of the simpler system. The effectiveness of the proposed strategy is demonstrated by means of two numerical examples.
Leaky coaxial cable characteristics at 900 MHz

Mobile communication through electromagnetically obstructed areas can be established by using wayside leaky coaxial cables. Available experimental data had been limited to 450 MHz. This paper presents the results of a recent experiment of the RADIAX cable at 900 MHz in near-field. These data are used to supplement an earlier RADIAX experiment at frequencies below 450 MHz and to compare with a theoretical study at 1 GHz.
Gromov–Witten Invariants of Toric Fibrations

Author(s): Brown, Jeffrey Steven | Advisor(s): Givental, Alexander B | Abstract: We prove a conjecture of Artur Elezi in a generalized form suggested by Givental. Namely, our main result relates genus-0 Gromov--Witten invariants of a bundle space with such invariants of the base, provided that the fiber is a toric manifold. When the base is the point, a new proof of mirror theorems by A. Givental and H. Iritani for toric manifolds is obtained.
Understanding online customers’ ties to merchants: the moderating influence of trust on the relationship between switching costs and e-loyalty

Fostering customer loyalty is a key objective for online businesses. Initial transactions with new customers are less profitable than transactions with existing customers, making loyalty an importa...
Characterization of thin and ultrathin polymer and resist films

The need for a better understanding of the physicochemical properties of radiation-sensitive thin polymer coatings for lithographic applications is driven by the trend of ever-shrinking pattern dimensions and film thickness, imposed by the semiconductor industry. In this work, we address the issue of film uniformity and moisture absorption for thin and ultrathin films (250 nm to 50 nm) of poly 4-hydroxystyrene (PHS). Using high resolution x-ray reflectivity, the roughness and density of spin coated films was found to remain constant within experimental error for the thickness range examined. Also, water uptake on PHS films was studied by neutron and x-ray reflectivity. Exposure of the polymer film to a controlled humidity level is shown to swell the polymer and be absorbed uniformly throughout the film. No preferential absorption of water at the interface was noticed, regardless of the hydrophilic or hydrophobic nature of the substrate surface. Overall density changes in the polymer matrix due to the moisture-induced increase in the film thickness are also discussed.
X-ray diffraction studies of catalysts

Abstract With the new high-intensity X-ray sources, by using anomalous scattering and glancing incidence, it is now possible to obtain considerable statistical information on catalysts-supported metals (size distribution and perfection), micron-sized single-crystal particles (structure), and the nature of surfaces. Examples of work on catalyst materials is given to illustrate these possibilities.
Heat pipe development for high temperature recuperator application

Abstract Heat pipes have been developed for operation in oxidizing atmospheres at temperatures above 1100 K. The heat pipes comprise a metallic liner and wick structure with a protective outer shell of an oxidation resistant material. The working fluids used in the heat pipes are alkali metals. A number of configurations have been evaluated, ranging from pipes using a metallic inner liner of a chemically vapor deposited (CVD) refractory metal applied to ceramic tubing, to one utilizing ferrous materials with an outer layer of a developed oxide. A promising intermediate configuration consisting of free-standing refractory tubing covered with a layered structure of fine grain, equi-axed CVD silicon carbide has also been evaluated. The test heat pipe was fabricated using low-carbon, arc-cast molybdenum tubing and a wick composed of 150 mesh molybdenum screen. Hafnium gettering was used with sodium working fluid. Assembly of the pipe was by electron beam welding. Following closure and capping of the fill tube the assembly was operated in a vacuum for several hours prior to the chemical vapor deposition of the exterior ceramic coating. After coating, the pipe was operated in air and in combusion gases for performance evaluation. The use of iron-chromium-aluminium alloys as container materials for operating in high temperature oxidizing and sulfiding gas streams has been investigated. Alloys of this type develop heavy, protective oxide surface layers when exposed to high temperature oxidizing atmospheres, and are commonly used in electrical heating elements because of their exceptional oxidation resistance. A heat pipe was assembled from Kanthal A-1 seam welded tubing in order to establish limits of operation for these materials. The heat pipe employed a 150 × 150 mesh 316 stainless steel (SS) screen wick and hafnium foils for oxygen gettering with sodium used as the working fluid. This heat pipe has been tested in a fossil fired flame above 1200 K to determine its operating characteristics and the durability of the material.
Modeling of Photoionized Plasmas

In this paper I review the motivation and current status of modeling of plasmas exposed to strong radiation fields, as it applies to the study of cosmic X-ray sources. This includes some of the astrophysical issues which can be addressed, the ingredients for the models, the current computational tools, the limitations imposed by currently available atomic data, and the validity of some of the standard assumptions. I will also discuss ideas for the future: challenges associated with future missions, opportunities presented by improved computers, and goals for atomic data collection.
The Complex Core of Abell 2199: The X-Ray and Radio Interaction

The cluster Abell 2199 is one of the prototypical "cooling flow" clusters. Its central cD galaxy is host to a steep spectrum radio source of the type associated with cooling cores. In this paper, we combine radio data with new ROSAT HRI data to show that conditions in its inner core, 50 kpc, are complex and interesting. Energy and momentum flux from the radio jet have been significant in the dynamics of the gas in the core. In addition, the Faraday data detects a dynamically important magnetic field there. The core of the X-ray luminous gas is not a simple, spherically symmetric cooling inflow. In addition, we believe the X-ray gas has had strong effects on the radio source. It seems to have disrupted the jet flow, which has led to a dynamical history very different from the usual radio galaxy. This particular source is much younger than the galaxy, which suggests the disruptive effects lead to an on-off duty cycle for such sources.
Guided-mode resonance sensor with extended spatial sensitivity

We propose a novel design for a guided-mode resonance (GMR) grating sensor that extends the sensitivity to a large region of space, possibly several tens of microns away from the grating surface. This type of sensors has high sensitivity in the half-space above the grating, close to the theoretical limit, together with a controllable - potentially very high - quality factor. It relies on a resonance caused by a "confined" mode of a sub-wavelength thick grating slab, a mode that is largely expelled from the grating itself into the grating environment. The small thickness assumption allows us to derive a simple yet accurate analytical model for the sensor behavior, which is tested numerically using a rigorous coupled-wave analysis (RCWA) method as well as in preliminary grating transmission measurements.
Heavy flavor hadrons in statistical hadronization of strangeness-rich QGP

We study b and c quark hadronization from QGP. We obtain the yields of charm and bottom flavored hadrons within the statistical hadronization model. The important novel feature of this study is that we take into account the high strangeness and entropy content of QGP, conserving the strangeness and entropy yields at hadronization.
Built-in checking of the correct self-test signature

A procedure is described for determining the initial value of a single or multiple input signature register (used to compress responses in built-in testing) so that the final good-machine signature is always constant, e.g. all zeros. In this way, it is possible to determine if a fault has been detected by ORing the outputs of the register stages. Since the OR operation can be built-in, a single observation of the output of the OR gate will determine if the circuit has passed the test. >
Self-dual Yang-Mills theory and one-loop maximally helicity violating multi-gluon amplitudes

Abstract A scalar cubic action that classically reproduces the self-dual Yang-Mills equations is shown to generate one-loop QCD amplitudes for external gluon all with the same helicity. This result is related to the symmetries of the self-dual Yang-Mills equations.
In-Class vs. Online Experiments: Is There a Difference?

Classroom experiments in economics continue to increase in popularity. While early experiments were often hand-run in class, now computerized online experiments are also widely available. Using a quasiexperimental approach, the authors investigated whether any difference in student achievement (as measured by course scores and the Test of Understanding in College Economics (TUCE) (Saunders 1991)) or other outcomes exists between students exposed to experiments in class and students exposed to them online. In this investigation, class sections differed only in the manner through which the experiments were administered: manually in class; or computerized online. The authors found no significant difference in student achievement or overall views of the course or instructor between the two treatments. The authors did, however, find that students exposed to hand-run experiments report more favorable views of the experimental pedagogy and report higher levels of interaction with their classmates.
Hunting the Scalar Glueball: Prospects for BES III

The search for the ground state scalar glueball G0 is reviewed. Spin zero glueballs will have unique dynamical properties if the amplitude is suppressed by chiral symmetry, as it is to all orders in perturbation theory: for instance, mixing of G0 with mesons would be suppressed, radiative Ψ decay would be a filter for new physics in the spin zero channel, and the decay could be enhanced relative to G0 → ππ. These properties are consistent with the identification of f0(1710) as the largely unmixed ground state scalar glueball, while recent BES data implies that f0(1500) does not contain the dominant glueball admixture. Three hypotheses are discussed: that G0 is 1) predominantly f0(1500) or 2) predominantly f0(1710) or 3) is strongly mixed between f0(1500) and f0(1710).
Speech and the unspeakable in the "place" of the unconscious

According to a large body of persuasion within our culture, language and speech are limited by what cannot become a part of linguistic expression. There is a boundary beyond which "reality" or "being" or "body" cannot be said. Language and speech happen as commu nicability and communicating, and the presence of "nature" or "di? vinity" or "matter" can be communicated at best only partially. They are beyond the reach and power of discourse. Discursive reality has an accessibility and meaning that are unique for language. The unspeak? able, the mysterious, surd, or in itself happen like barriers to our most human capacity. They allow us to know of the limitedness of speech and language and give us a point of reference, at least, by which we may know that we live in a sea of other-than-language. Or perhaps the difference between speech and the unspeakable com? municates. Perhaps this difference itself occurs in speech and language and communicates both what cannot be said directly and the limits of speaking as such. Perhaps the limits of speaking reveal nothing at all, like emptiness or complete absence of order. Further, instead of speaking analogously in relation to something totally outside of lan? guage, something timeless and therefore not directly speakable, per? haps we speak within the limits of one or another discourse whose specific way of being temporal makes some kinds of things seem outside of time and the range of speech and language. Perhaps if we see the present differences sharply enough, if we see them with enough reflective discipline, we can understand the limits of time not by means of the presence of "reality" without time, but by means of another discourse that shows the limits of this former discourse by saying what this discourse cannot say. Perhaps "timelessness' and "deathlessness"
General relativistic models for the electron

Abstract A model is proposed for the classical electron as a point charge with finite electromagnetic self-energy. Modifications of the Reissner—Nordstrom (spin 0) and Kerr—Newman (spin 1 2 solutions of the Einstein—Maxwell equations are derived. It is conjectured that spacetime curvature very close to the point charge deforms the electric and magnetic fields such as to reduce the self-energy to a finite value by means of Hawking polarization of the vacuum, much like that around a black hole.
Lipid suppression in CSI with spatial priors and highly undersampled peripheral k-space.

Mapping 1 H brain metabolites using chemical shift imaging is hampered by the presence of subcutaneous lipid signals, which contaminate the metabolites by ringing due to limited spatial resolution. Even though chemical shift imaging at spatial resolution high enough to mitigate the lipid artifacts is infeasible due to signal-to-noise constraints on the metabolites, the lipid signals have orders of magnitude of higher concentration, which enables the collection of high-resolution lipid maps with adequate signal-to-noise. The previously proposed dual-density approach exploits this high signal-to-noise property of the lipid layer to suppress truncation artifacts using high-resolution lipid maps. Another recent approach for lipid suppression makes use of the fact that metabolite and lipid spectra are approximately orthogonal, and seeks sparse metabolite spectra when projected onto lipid-basis functions. This work combines and extends the dual-density approach and the lipid-basis penalty, while estimating the high-resolution lipid image from 2-average k-space data to incur minimal increase on the scan time. Further, we exploit the spectral-spatial sparsity of the lipid ring and propose to estimate it from substantially undersampled (acceleration R 5 10 in the peripheral k-space) 2-average in vivo data using compressed sensing and still obtain improved lipid suppression relative to using dual-density or lipid-basis penalty alone. Magn Reson Med 000:000–000, 2012. V C 2012 Wiley Periodicals, Inc.
Urea-catalyzed construction of oxazinanes

Highly functionalized oxazinanes are efficiently prepared through urea-catalyzed formal [3 + 3] cycloaddition reactions of nitrones and nitrocyclopropane carboxylates. The reaction system is general with respect to both the nitrocyclopropane carboxylates and nitrones enabling the preparation of a large family of oxazinanes, typically in high yield. This method affords access to enantioenriched oxazinane products through chirality transfer from enantioenriched nitrocyclopropane carboxylates.
Interorganizational GIS: Issues and prospects

Better analysis and understanding of local and regional phenomena can result from large scale data built by a variety of local government agencies and private sector organizations. Reducing duplication and saving organizational resources are two main arguments for sharing geographic data and systems. This, however, is quite challenging and requires extensive interorganizational coordination. Drawing on existing literature and focusing primarily on local government settings, this paper reviews the major issues related to coordinated development and use of local geographic information systems and databases. These issues include motivation for sharing, coordination process, organizational factors, standardization and interoperability, cost of coordination, and mechanisms for GIS sharing.
Selective catalysis of ester aminolysis: an approach to peptide active esters

Model studies have been carried out in which the Kaiser-DeGrado procedure for solid-phase synthesis has been combined with the use of reactants with a latent activation feature as a potential route to peptide active esters. The rates of reaction of the 4-(methylthio)phenyl ester of L-phenylalanine with itself, as well as those of a close analogue with tert-butyloxycarbonylglycine bound to a benzophenone oxime functionalized polystyrene resin have been measured in the presence of varying concentrations of the aminolysis catalyst, acetic acid. These studies indicate that under appropriate conditions, it is possible to generate the 4-(methylthio)phenyl esters of suitable peptides, synthesized by solid-phase methods on the oxime-functionalized resin. These peptide esters can then be oxidized to the more strongly electrophilic sulfone derivatives. The preparations of the 4-(methylsulfonyl)phenyl esters of N-tert-butyloxycarbonylglycyl-L-phenylalanine and N-carbobenzyloxy-O-carbobenzyloxy-L-tyrosylglycylglycyl-L-phenylalanine are described as examples of the use of this method of preparing peptide active esters
Approximate optimal atmospheric entry trajectories

For a reentry glider, approximate solutions are found in closed form for the problem of maximizing a function of the terminal velocity, altitude, flight-path angle and heading angle subject to, at most, three terminal nonlinear constraints. The results given here extend the previous results in two important ways: (1) the second-order approximation of the entry dynamics of Loh is used instead of the first-order approximation of Allen and Eggers. This approximation is found to compare extremely well with an exact numerical optimal path. (2) A three-dimensional optimization problem is solved which includes Loh's second-order approximation where the roll angle as well as the lift coefficient are determined subject to constraints which include the terminal heading angle. Furthermore, closed-form solutions can also be obtained subject to in-flight constraints on the lift coefficient and roll angle.
The quantum hydrodynamic formulation of Dirac equation and its generalized stochastic and non-linear analogs

The quantum hydrodynamic-like equations as a function of two real sets of variables (i.e., the 4x4 action matrix and the 4-dimensional wave function modulus vector) of the Dirac equation are derived in the present work. The paper shows that in the low velocity limit the equations lead to the hydrodynamic representation of the Pauli’s equation for charged particle with spin given by Janossy [1] and by Bialynicki et al [2]. The Lorentz invariance of the relativistic quantum potential that generates the non-local behavior of the quantum mechanics is discussed.
Preparation of Pt/alumina catalysts by the sol-gel method

A series of alumina-supported Pt catalysts were prepared by using the sol-gel method. The effect of the variables of preparation, the nature of solvent removal and pretreatment were investigated. The total surface area, pore size distributions, Pt dispersions, and catalytic reactivity were measured for the various samples. It was determined that a stoichiometric water/aluminum alkoxide molar ratio of 3.0 gave the sample with the highest surface area. These sol-gel samples were fairly active in the reactions of n-hexane and showed desirable selectivities. Xerogel samples were found to be superior in comparison to the corresponding aerogel samples as far as total surface area and metallic dispersions were concerned. Mixing of silica to the alumina (after a prehydrolysis step) to an extent of 5 wt%, in order to form a 1.0 Pt/(95% alumina-5% silica) mixed metal oxide sample, increased the sample total surface area and metallic dispersion by a small extent, in comparison to the 1.0 Pt/alumina sample.
Diversity of Decline-Rate-Corrected Type Ia Supernova Rise Times: One Mode or Two?

B-band light-curve rise times for eight unusually well-observed nearby Type Ia supernovae (SNe Ia) are fitted by a newly developed template-building algorithm, using light-curve functions that are smooth, flexible, and free of potential bias from externally derived templates and other prior assumptions. From the available literature, photometric BVRI data collected over many months, including the earliest points, are reconciled, combined, and fitted to a unique time of explosion for each SN. On average, after they are corrected for light-curve decline rate, three SNe rise in -->18.81 ± 0.36 days, while five SNe rise in -->16.64 ± 0.21 days. If all eight SNe are sampled from a single parent population (a hypothesis not favored by statistical tests), the rms intrinsic scatter of the decline rate-corrected SN rise time is -->0.96−0.25+0.52 days, a first measurement of this dispersion. The corresponding global mean rise time is -->17.44 ± 0.39 days, where the uncertainty is dominated by intrinsic variance. This value is 2 days shorter than two published averages that nominally are twice as precise, although also based on small samples. When comparing high-z to low-z SN luminosities for determining cosmological parameters, bias can be introduced by use of a light-curve template with an unrealistic rise time. If the period over which light curves are sampled depends on z in a manner typical of current search and measurement strategies, a 2 day discrepancy in template rise time can bias the luminosity comparison by 0.03 mag.
Compensating payments and hazardous work in union and nonunion settings

This paper extends the results of past research on estimated compensating payments and estimated injury rate equations for the union and nonunion sectors. It allows for both simultaneity in the determination of income and safety and structural differences in their determinants across the two sectors. Although union settings are found to maintain larger compensating payments for hazardous work than nonunion settings, they also appear to contain higher injury rates, all else constant. A fuller understanding of these results will require further analysis of the differing institutional mechanisms for compensation and safety determination in union and nonunion labor markets.
Job flow dynamics and firing restrictions

Abstract This paper proposes and solves a stochastic search model with endogenous job separation and shows that the amplitude and time variation of job reallocation depend crucially upon the arrival rate of exogenous firing permissions. The tighter the firing restrictions, the less volatile is job destruction and the higher the correlation between job reallocation and net employment changes. Furthermore, as firing restrictions increase, the average level of job reallocation falls while equilibrium unemployment is approximately constant. A parameterization of the model can rationalize cross-country differences in the cyclical behaviour of job creation and destruction.