cssi/SciSciGPT-SciSciNet huggingface dataset:
Permissible Perfidy? Analysing the Colombian Hostage Rescue, the Capture of Rebel Leaders and the World's Reaction

On 2 July 2008, Colombian forces disguised as an international humanitarian mission rescued 15 hostages from the Fuerzas Armadas Revolucionarias de Colombia guerilla group, its opponent in a decades-long conflict. Those forces also captured two guerrillas, including the commander who had been responsible for the hostages. The world’s reaction, including those of humanitarian and human rights organizations, was universally positive in spite of reports that Colombian commandos and intelligence agents posed as aid workers and journalists c non-combatants protected by international humanitarian law (IHL) c in effecting the rescue and capture. Criticism of the operation later arose only when it was discovered that at least one of the Colombian soldiers participating in the operation wore the emblem of the International Committee of the Red Cross. Even that criticism focused solely on the misuse of the emblem, not the feigning of non-combatant status resulting in capture. The author examines the rescue operation to determine whether and how it might have violated IHL prohibitions regarding perfidious capture, recently asserted to apply in both international and non-international armed conflict. He reviews the perfidy prohibition, its scope and applicability, and possible interpretations that might explain the world’s uncritical reaction to the operation. He also examines doctrines that might preclude or negate potential criminal responsibility for individual participants or decision-makers, as well as those that might apply at a collective level. The author argues that the lack of the clear applicability of any doctrine precluding criminal responsibility for this supposed violation of IHL might confirm
Stability of Slag in Turbulent MHD Boundary Layers

The general problem of liquid layer stability is considered in the presence of body forces, and the pressure and shear perturbations generated by an external gas flow. In particular, linear stability analyses are applied to a liquid slag layer driven by a turbulent gaseous boundary layer in the presence of electromotive forces in an MHD channel. It is shown that entrainment of slag could occur in subsonic flows but that the slag layer is stable in supersonic flows. Typical results exhibit disturbance growth rates, phase velocities and disturbance frequencies as functions of liquid Reynolds number and interface shear stress. Within the restrictive assumptions of the analysis, the results show reasonable agreement with available experimental data.
Optimal auctions for asymmetrically budget constrained bidders

We consider an environment with a single divisible good and two bidders. The valuations of the bidders are private information but one bidder has a commonly known budget constraint. For this environment we derive the revenue maximizing subsidy free dominant strategy incentive compatible auction.
An economic analysis of lead paint laws

In this paper we develop a theoretical framework for determining whether laws designed to reduce lead paint risk are consistent with efficiency. We do this in the context of both owner-occupied and rental housing, and under different informational scenarios depending on who has knowledge about the risk. Our results suggest that efficient lead paint laws would impose on property owners and landlords a duty to notify buyers and tenants about known risks but would not impose on them a duty to inspect for or abate the risk. Our review of the existing law shows that common law standards are largely consistent with efficiency, but statutory law is not.
How Does Value Added Compare to Student Growth Percentiles

We compare teacher evaluation scores from a typical value-added model to results from the Colorado Growth Model (CGM), which 16 states currently use or plan to use as a component of their teacher performance evaluations. The CGM assigns a growth percentile to each student by comparing each student's achievement to that of other students with similar past test scores. The median (or average) growth percentile of a teacher's students provides the measure of teacher effectiveness. The CGM does not account for other student background characteristics and excludes other features included in many value-added models used by states and school districts. Using data from the District of Columbia Public Schools (DCPS), we examine changes in evaluation scores across the two methods for all teachers and for teacher subgroups. We find that use of growth percentiles in place of value added would have altered evaluation consequences for 14% of DCPS teachers. Most differences in evaluation scores based on the two methods ...
Is there an Aoki phase in quenched QCD

We argue that quenched QCD has non-trivial phase structure for negative quark mass, including the possibility of a parity-flavor breaking Aoki phase. This has implications for simulations with domain-wall or overlap fermions.
Free Radical Cyclizations in Alkaloid Total Synthesis: (±)-21-Oxogelsemine and (±)-Gelsemine

Total syntheses of (±)-21-oxogelsemine (3) and (±)-gelsemine (1) are described. Free radical cyclizations play important roles in constructing the tricyclic core (40 → 41) and oxindole (93 → 96) substructures of the target alkaloids, and an isomerization−cyclization strategy (101 → 102) was used to complete construction of the gelsemine cage. Observations made along the way include intramolecular 1,4- and 1,6-hydrogen atom transfers (64 → 65 and 40 → 47) and a free radical cyclization-fragmentation sequence (85 → 86 + 87). A retroaldol−aldol strategy for adjusting oxindole stereochemistry in gelsemine-like structures is also described (72 → 74 and 86 → 87).
Coherent control of lattice deformations in quantum wires by optical self-trapping

We investigate theoretically a semiconductor quantum wire under the effect of an intense off-resonant cw laser. We show that in the regime of strong exciton-phonon coupling the light-dressed ground state of the wire reveals symmetry-breaking features, leading to local lattice deformations. Due to the off-resonant nature of the excitation, the deformations are reversible and controllable by the intensity and frequency of the laser. We calculate the light-induced strain forces on the lattice in the case of an organic quantum wire.
Structure analysis of CVD graphene films based on HRTEM contrast simulations

Low-voltage, aberration-corrected, High-Resolution Transmission Electron Microscopy (HRTEM) has proven to be an excellent tool for structure analysis of graphene films, which are typically one or a few atoms thick. Experimental observations of graphene films by HRTEM exhibit several challenges due to low contrast and sensitivity of graphene to intense electron beams. Hence the contrast interpretation requires computer simulations for reliable structure identification. HRTEM contrast simulations of graphene films based on multislice algorithms are presented and compared to experimental results. Stacking sequence, and the number of layers have been analyzed in conjunction with imaging conditions.
Effects of internal stresses on the thermomechanical behavior of Sn-based solder joints

Solder joints are multi-component systems with several entities. When such a joint is subjected to a temperature excursion during service, large stresses can arise due to different coefficients of thermal expansion (CTE) of components that make up the joint. The magnitude of stresses that can develop not only depends on the temperature differences encountered, but also on rates at which such changes are imposed and the dwell times at the temperature extremes. Severe anisotropy of tin, and constraints imposed by the entities present in the joint on the solder behavior, also play significant roles in the development of these stresses in tin-based solder joints. Since the extents of internal stress build up is dependant on material behaviors, such as strain-rate sensitivity, stress relaxation, etc., adaptation of service parameters, such as, heating/cooling rates and dwell times at temperature extreme during TMF are viable options to minimize the internal stress. Since solder is at a high homologous temperature during service, the predominant damage mode is grain boundary sliding and presence of submicron size stable reinforcements that are strongly bonded to the Sn grain boundary is a suitable means to reduce TMF damage.
HOPT: A myopic version of the STOCHOPT automatic file migration policy

The STOCHOPT automatic file migration policy (proposed by A.J. Smith) minimizes the expected retention and recall costs of an abitrarily sized file. We consider the application of the STOCHOPT policy to a file system in which the file inter-reference time (IRT) distributions are characterized by strictly monotonically decreasing hazard rates (SDHR) (also known as decreasing failure rates, DFR). We show that in this case the STOCHOPT policy can be simply stated in terms of a scaled hazard rate, i.e., the hazard rate divided by the file size. Such decreasing failure rate distributions have been used by Smith to model empirically observed file inter-reference times.
Insect Control Vs. Human Nutrition

The American people enjoy the most abundant and varied diet of any nation in history, thanks to modern technology. At the same time the Food Protection Committee of the National Research Council warns that “Maintenance of the present nutritional status of the American public is contingent upon the continued production of an adequate food supply. Plant and animal pests rank among the foremost causes of food destruction, food deterioration, and food contamination. Hence, the necessity of protecting growing crops and produce from serious attack by insects, plant diseases, and other pests is quite obvious to all concerned” (Safe Use of Chemical Additives in Foods, N. R. C. (1952)). Such warnings notwithstanding, the American public seems prone to take our bountiful and varied food supply for granted, totally oblivious of the fact that man is engaged in a never-ending conflict with insects for every crop he grows.
The influence of chemical composition on models of Type Ia supernovae

Type Ia supernovae are bright stellar explosions distinguished by standardizable light curves that allow for their use as distance indicators for cosmological studies. Despite the highly successful use of these events in this capacity, many fundamental questions remain. Contemporary research investigates how properties of the progenitor system that follow from the host galaxy such as composition and age influence the brightness of an event with the goal of better understanding and assessing the intrinsic scatter in the brightness. We provide an overview of these supernovae and proposed progenitor systems, all of which involve one or more compact stars known as white dwarfs. We describe contemporary research investigating how the composition and structure of the progenitor white dwarf systematically influences the explosion outcome assuming the progenitor is a single white dwarf that has gained mass from a companion. We present results illustrating some of these systematic effects from our research.
Finite Sample Theory of QMLE in ARCH Models with Dynamics in the Mean Equation

We provide simulation and theoretical results concerning the finite-sample theory of quasi-maximum-likelihood estimators in autoregressive conditional heteroskedastic (ARCH) models when we include dynamics in the mean equation. In the setting of the AR(q)–ARCH(p), we find that in some cases bias correction is necessary even for sample sizes of 100, especially when the ARCH order increases. We warn about the existence of important biases and potentially low power of the t-tests in these cases. We also propose ways to deal with them. We also find simulation evidence that when conditional heteroskedasticity increases, the mean-squared error of the maximum-likelihood estimator of the AR(1) parameter in the mean equation of an AR(1)-ARCH(1) model is reduced. Finally, we generalize the Lumsdaine [J. Bus. Econ. Stat. 13 (1995) pp. 1–10] invariance properties for the biases in these situations.
Design of a Novel 3D Printed Bioactive Nanocomposite Scaffold for Improved Osteochondral Regeneration

Chronic and acute osteochondral defects as a result of osteoarthritis and trauma present a common and serious clinical problem due to the tissue’s inherent complexity and poor regenerative capacity. In addition, cells within the osteochondral tissue are in intimate contact with a 3D nanostructured extracellular matrix composed of numerous bioactive organic and inorganic components. As an emerging manufacturing technique, 3D printing offers great precision and control over the microarchitecture, shape, and composition of tissue scaffolds. Therefore, the objective of this study is to develop a biomimetic 3D printed nanocomposite scaffold with integrated differentiation cues for improved osteochondral tissue regeneration. Through the combination of novel nano-inks composed of organic and inorganic bioactive factors and advanced 3D printing, we have successfully fabricated a series of novel constructs which closely mimic the native 3D extracellular environment with hierarchical nanoroughness, microstructure, and spatiotemporal bioactive cues. Our results illustrate several key characteristics of the 3D printed nanocomposite scaffold to include improved mechanical properties as well as excellent cytocompatibility for enhanced human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation in vitro. The present work further illustrates the effectiveness of the scaffolds developed here as a promising and highly tunable platform for osteochondral tissue regeneration.
Current Standards of Care in Small-Cell and Non-Small-Cell Lung Cancer

Lung cancer is the leading cause of cancer-related death in the United States, accounting for over 30% of cancer deaths in men and 25% in women. Small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC) are uniformly aggressive tumors, with rates of regional or distant metastases at diagnosis as high as 70%. Because the majority of these tumors are unresectable, patients with relatively good performance status receive platinum-based chemotherapy. Although no treatment consensus exists, currently recommended regimens for SCLC include PE (cisplatin and etoposide), CAV (cyclophosphamide, doxorubicin, and vincristine), CAE (cyclophosphamide, doxorubicin, and etoposide), and CAVE (cyclophosphamide, doxorubicin, vincristine, and etoposide). Of these, the PE regimen has been widely accepted in the United States, although CE (carboplatin and etoposide) provides better tolerability. For NSCLC, standard chemotherapy regimens have included platinum-based therapy (cisplatin and a vinca alkaloid or PE). Data from recent studies suggest that the addition of paclitaxel to platinum modestly improves tumor response and survival in NSCLC. Although SCLC and NSCLC are both responsive to first-line chemotherapy, most patients relapse and die from their disease, with 5-year survival rates of approximately 15%. Given the disappointing survival rates associated with SCLC and NSCLC, the introduction of new cytotoxic agents has been eagerly anticipated. Evidence of improved response and extended survival is mounting for various combinations of established regimens (e.g., PE) with newer drugs exhibiting novel mechanisms of action and single-agent antitumor activity, such as gemcitabine, paclitaxel, docetaxel, vinorelbine, and topotecan. This article reviews the current standards of care in SCLC and NSCLC, and introduces the potential role of newer agents given in combination with standard chemotherapy.
Stability of thin solid films

Abstract A small amplitude perturbation analysis is used to determine the conditions under which a solid film several hundred angstroms thick on a substrate will rupture. If the perturbation grows with time the film is unstable and rupture may occur, whereas if the perturbation decays the film is stable. Film rupture is caused essentially by diffusion of atoms along the free interface of the film which can, under certain conditions, amplify a perturbation applied to the film-gas interface. This surface diffusion is generated by a gradient of the chemical potential along the free interface. The chemical potential is affected by the curvature of the interface, by the pre-existing internal stresses normally found in thin films (they generate a strain energy term in the chemical potential) and by interaction forces between the atoms at the gas-solid interface with those of the film and substrate. The thin film is assumed to behave like an elastic body. The difference in the forces which act on a volume element in a film thinner than the range of interaction forces between the atoms of the film and substrate and the forces in a bulk solid is accounted for by introducing a body force into the equations of displacement of an elastic solid. Because of the difficulties in writing boundary conditions at the film-substrate interface, two limiting situations are considered: (1) a thin film on a rigid substrate and (2) a thin free film. A critical internal stress necessary for rupture is identified. The time of rupture is estimated from the inverse of the maximum growth coefficient of the perturbation. The dominant wavelength corresponding to the maximum growth coefficient gives an idea as to the size of the islands formed through rupture.
Dynamic Motion Vision

We present a method for the recovery of environment structure and camera motion from a sequence of images taken by a camera in motion. Unlike previous approaches, our method of Dynamic Motion Vision explicitly models the perceived temporal variation of the scene structure in the form of a dynamical system. We use the Kalman Filter algorithm to optimally estimate depth values at every picture cell from optical flow. We interleave a least-squares motion estimation with the stages of the Kalman Filter. Our algorithm can therefore estimate both the structure of a scene and the camera motion simultaneously in an incremental fashion which improves the estimates as new images become available. Results of experiments on synthetic and real images are presented.
Confinement-driven Spatial Variations in the Cosmic-Ray Flux

Low-energy cosmic rays (CRs) are confined by self-generated MHD waves in the mostly neutral interstellar medium. We show that the CR transport equation can be expressed as a continuity equation for the CR number density involving an effective convection velocity. Assuming a balance between wave growth and ion-neutral damping, this equation gives a steady state condition ncr ∝ n up to a critical density for free streaming. This relation naturally accounts for the heretofore unexplained difference in CR ionization rates derived for dense diffuse clouds (McCall et al.) and dark clouds, and predicts large spatial variations in the CR heating rate and pressure.
A Ray-Tracing Algorithm for Spinning Compact Object Spacetimes with Arbitrary Quadrupole Moments. I. Quasi-Kerr Black Holes

We describe a new numerical algorithm for ray tracing in the external spacetimes of spinning compact objects characterized by arbitrary quadrupole moments. Such spacetimes describe non-Kerr vacuum solutions that can be used to test the no-hair theorem in conjunction with observations of accreting black holes. They are also appropriate for neutron stars with spin frequencies in the 300-600 Hz range, which are typical of the bursting sources in low-mass X-ray binaries. We use our algorithm to show that allowing for the quadrupole moment of the spacetime to take arbitrary values leads to observable effects in the profiles of relativistic broadened fluorescent iron lines from geometrically thin accretion disks.
Processing and Characterization of Thermoplastic Polyurethane Nanocomposite Thin Films

In this article, we have set up protocols for fabricating thermoplastic polyurethane thin films of about 30 μm (neat polyurethane and carbon nanofiber (CNF) containing polyurethane) via ultrasound assisted atomization at 20 kHz. From processing to thin film peel off, we have set up procedures for fabricating our samples. Using optical microscopy, we have examined the manufacturing of these films from a droplet diameter perspective. Our optical microscopy results indicate that the final film microstructure was directly dependent on the physical properties of the neat/CNF reinforced solution. Mechanical testing of these films was then carefully carried out using a dynamic mechanical analyzer (DMA) unit utilizing a specialized thin film test clamp fixture. These test results were compared with control cast films fabricated from the same solutions. For the similar extensions, we observed a drastic increase in the softness of the atomized f i lm. We surmise that the ultrasound assisted droplet generation concurrent with secondary atomization and evaporation could have resulted in reduction of the molecular weight of the polyurethane in our atomized samples relative to the neat ones. Differential scanning calorimetry (DSC) scans have been conducted to confirm the changes in molecular weight. Although results were inconclusive there is evidence of exotherms at 49C in our atomized samples suggested of changes to molecular weight distribution.
Symplectic structures and self-dual fields in (4k + 2) dimensions

Abstract We discuss symplectic structures for the chiral boson in (1+1) dimensions and the self-dual field in (4 k +2) dimensions. Dimensional reduction of the six-dimensional field on a torus is also considered.
Inverse Transport with Isotropic Time-harmonic Sources

This paper concerns the reconstruction of the scattering coefficient in a two-dimensional transport equation from angularly averaged measurements when the probing source is isotropic and time-harmonic. This is a practical setting in the medical imaging modality called optical tomography. As the modulation frequency of the source increases, we show that the reconstruction of the scattering coefficient improves. More precisely, as the frequency $\omega$ increases, we show that all frequencies of the scattering coefficient lower than b are reconstructed stably with an accuracy that improves as $\omega$ increases and b decreases. The proofs are based on an analysis of the single scattering singularities of the transport equation and on careful analyses of oscillatory integrals by stationary phase arguments.
Doppler imaging of plasma modes in a Penning trap

We describe a technique and present results for imaging the modes of a laser-cooled plasma of 9Be+ ions in a Penning trap. The modes are excited by sinusoidally time-varying potentials applied to the trap electrodes. They are imaged by changes in the ion resonance fluorescence produced by Doppler shifts from the coherent ion velocities of the mode. For the geometry and conditions of this experiment, the mode frequencies and eigenfunctions have been calculated analytically. A comparison between theory and experiment for some of the azimuthally symmetric modes shows good agreement.
Selective N-alkylation of pyrrolopyrimidines and indoles by “transfer of activation”

Abstract The benzene sulfonyl group is used as a “transfer of activation” reagent to alkylate selectively the N -H of both pyrrolopyrimidines and 5-aminoindoles substituted on thienopyrimidines. A variety of primary and secondary alcohols are utilized as alkylating substrates.
Quantum circuit design for solving linear systems of equations

Recently, it has been demonstrated that quantum computers can be used for solving linear systems of algebraic equations with exponential speedup compared with classical computers. Here, we present an efficient and generic quantum circuit design for implementing the algorithm for solving linear systems. In particular, we show the detailed construction of a quantum circuit which solves a 4 × 4 linear system with seven qubits. It consists of only the basic quantum gates that can be realized with present physical devices, implying great possibility for experimental implementation. Furthermore, the performance of the circuit is numerically simulated and its ability to solve the intended linear system is verified.
Synergy between the antinociceptive effects of intrathecal clonidine and systemic morphine in the rat.

Abstract These experiments tested the hypothesis that intrathecal α2-adrenergic antinociception could be potentiated by the concurrent administration of systemic morphine. Thirty-four male rats, implanted with chronic indwelling intrathecal catheters, received a subcutaneous injection of either morphine sulfate or an equal volume of saline, followed by an intrathecal injection of clonidine HCl or an equal volume of vehicle. Antinociception was assessed using the tail-flick test. Tail-flick latencies following subcutaneous morphine plus intrathecal vehicle, or subcutaneous saline plus intrathecal clonidine were not significantly different from baseline. However, the combination of subcutaneous morphine plus intrathecal clonidine produced a significant antinociceptive effect. Such potentiation may prove to be a useful clinical strategy to help maximize analgesia, minimize side effects and attenuate the development of tolerance.
The Source of Some Paradoxes from Social Choice and Probability

Abstract An elementary argument is developed to explain and unite several paradoxes coming from probability and from social choice. This geometric approach is illustrated with new results about the intransitivities of election rankings over subsets of alternatives, agenda manipulation, conditional probability, and waiting times.
Volume and homology of one-cusped hyperbolic 3-manifolds

Let M be a complete, finite-volume, orientable hyperbolic manifold having exactly one cusp. If we assume that 1.M / has no subgroup isomorphic to a genus–2 surface group and that either (a) dimZp H1.M IZp/ 5 for some prime p , or (b) dimZ2H1.M IZ2/ 4 , and the subspace of H .M IZ2/ spanned by the image of the cup product H .M IZ2/ H .M IZ2/!H .M IZ2/ has dimension at most 1 , then volM > 5:06: If we assume that dimZ2H1.M IZ2/ 7 and that the compact core N of M contains a genus–2 closed incompressible surface, then volM > 5:06: Furthermore, if we assume only that dimZ2H1.M IZ2/ 7 , then volM > 3:66:
Stability of Dislocation Short-Range Reactions in BCC Crystals

The stability of short-range reactions two dislocations of parallel line vectors which guide on two parallel slip planes in BCC crystals is determined. The two dislocations are assumed to be infinitely long, and their interaction is treated as elastic. The interaction and self-energies are both computed for dynamically moving dislocations, where the dependence on dislocation velocity is taken into account. The stability of the reaction is determined as a function of the following phase space variables: relative angle, relative speed, dislocation mobility, Burgers vector, separation of slip planes, and external force. The results indicate that the dynamic formation of dislocation dipoles or tilt wall embryos occurs only over a small range of the investigated phase space. Inertial effects are shown to be important at close separation, because of the large force between the two dislocations comprising the dipole or tilt wall embryo. The authors find that destabilization of the dislocation dipoles or tilt wall embryos is enhanced by externally applied stresses or by stress fields of neighboring dislocations.
History of Hydrogen Reionization in the Cold Dark Matter Model

We calculate the reionization history in CDM (cold dark matter) models. The epoch of the end of reionization and the Thomson scattering optical depth to the cosmic microwave background depend on the power spectrum amplitude on small scales and on the ionizing photon emissivity per unit mass in collapsed halos. We calibrate the emissivity to reproduce the measured ionizing background intensity at z = 4. Models in which all CDM halos have either a constant emissivity or a constant energy emitted per Hubble time per unit mass predict that reionization ends near z ~ 6 and that the optical depth is in the range 0.05 15 must have ionizing emissivities per unit mass larger by a factor 50 compared with the more massive halos that produce the ionizing emissivity at z = 4. This factor increases to 100 if the CDM power spectrum amplitude is required to agree with the recent Croft et al. measurement from the Lyα forest. If τe 0.17 is confirmed, a higher ionizing emissivity at z > 15 compared with z = 4 might arise from an enhanced star formation rate or quasar abundance per unit mass and an increased escape fraction for ionizing photons; the end of reionization could have been delayed to z ~ 6 because of the suppression of gas accretion and star formation in low-mass halos as the medium was reionized.
The Economics of Child Labor: Comment

In a recent paper, Kaushik Basu and Pham Hoang Van (BV, 1998) develop an important and very interesting model in which a fairly productive economy exhibits multiple equilibria, with children working in at least one. They identify two assumptions as essential to this result. The first - - which they call the "luxury axiom" - - is that a family sends its children to the labor market only if its income from sources other than child labor is very low. The second is embodied in their "substitution axiom" which states that from the point of view of firms, child labor is substitutable for adult labor. In this comment, we show that in addition to these two assumptions about the micro-level behavior of households and firms, there is also an essential macro-level assumption that may be termed the "distribution axiom:" income or wealth from non-labor sources must be sufficiently concentrated in the hands of a few agents. We establish that if non-labor income is distributed with sufficient equality, a market equilibrium with child labor cannot exist in the BV model. Beyond their contribution as an extension of BV's theory, our results formalize a proposition implicit in recent policy discussions of child labor. Christiaan Grootaert and Ravi Kanbur (1995) note that as household-level poverty is well-known to be the major cause of child labor, "[g]eneral economic development, equitably distributed, is the best and most sustainable way of reducing child labor." (p. 198, emphasis added) Policy documents from the International Labor Organization (ILO) have long conveyed this view, and now the World Bank appears to as well (Peter Fallon and Zafiris Tzannatos, 1998). There is a growing recognition that while economic development and development policies are necessary to eliminating child labor, they are not always sufficient on their own. Distributional considerations matter. Indeed, in the case in which BV's model yields multiple equilibria, the economy is developed enough to eliminate child labor. In this comment it becomes clear that if child labor exists in this economy, the causes are purely distributional.
Thermodynamic properties of silicalite SiO2

Abstract Silicalite, a polymorph of SiO 2 , is a new and interesting molecular-sieve material. Low-temperature (5 to 350 K) heat-capacity, flourine-combustion, high-temperature (350 to 1500 K) drop-calorimetric, and reaction-calorimetric with HF(aq) measurements have been performed on this material. At T ′ = 298.15 K, Δ f H m o ( T ′) = −(905.20±0.84) kJ·mol −1 ; C p , m o ( T ′) = (46.34±0.23) J·K −1 ·mol −1 ; { Δ 0 T ′ S m o ( T ′)} = (46.29±0.23) J·K −1 ·mol −1 ; and Δ f G m o ( T ′) = −(852.23±0.84) kJ·mol −1 . The enthalpies of reaction with 24.4 mass per cent hydrofluoric acid of silicalite at mass concentrations of 0.5, 1, 2, and 4 g·dm −3 were determined to be −(144.91±0.23), −(144.80±0.10), −(145.07±0.12), and −(145.06±0.14) kJ·mol −1 , respectively. The enthalpies of reaction of silicalite with 20.1 and 15.0 mass per cent hydrofluoric acid at a silicalite mass concentration of 1 g·dm −3 were determined to be −(143.85±0.19) and −(142.68±0.08) kJ·mol −1 , respectively. Because silicalite reacts rapidly with HF(aq) at 298.15 K, it has potential as a reference material for thermochemical measurements on inorganic silicates and silicate minerals. Silicalite is less stable than quartz, cristobalite, or tridymite, but more stable than SiO 2 (glass) or the high-pressure forms coesite or stishovite.
Building blocks for skipped polyols: syn-1,3-acetonides by chemoenzymatic synthesis from cycloheptatriene

Abstract Enantiopure enones obtained via lipase asymmetrization of meso -diols derived from cycloheptatriene underwent tin-directed ring-openings to give syn -1,3-bis(silyloxy) olefins which were converted to their acetonides in a one-pot sequence.
Medicare, access, and physicians' willingness to accept new Medicare patients

Abstract This paper examines the importance of Medicare reimbursement and other factors in determining physicians' willingness to accept new Medicare patients. A simple two-period, two-payer model is developed where profit maximizing physicians draw new patients from queues of each payer type, and are constrained to treat established patients that return for care. Under these assumptions, both current and future reimbursement are related to the decision to accept new Medicare patients, the impact of the latter depending on the turnover in patient load. The empirical results suggest that physicians' responses to current and expected future reimbursement differ by specialty.
Object extent determination for algebraic solid models

This paper presents methods for determination of spatial extent of algebraic solid models. Algebraic solid models are a variation of implicit solid models defined by implicit polynomial functions with rational coefficients. Spatial extent information, which can be used to enhance the performance of visualization and property evaluation, includes silhouettes, outlines and profiles. Silhouettes are curves on the surface of the solid which separate portions of the surface which face towards or away from a given viewpoint. The projection of the silhouette onto the viewing plane gives the outline of the solid, and the bivariate implicit function which defines the area enclosed by the outline is called the profile. A method for outline determination is demonstrated using concepts from algebraic geometry including polar surfaces and variable elimination via the Grobner basis method and/or resultants. Examples of outline generation are presented and a sample profile function is constructed
SYNTHETIC STUDIES TOWARD AMPHIDINOLIDE A : SYNTHESIS OF FULLY FUNCTIONALIZED SUBUNITS

A retrosynthetic breakdown of amphidinolide A affords four fragments A-D and illustrates the main synthetic challenges of this molecule. A concise stereoselective synthesis of the four appropriately functionalized subtargets is described. © 1999 Elsevier Science Ltd. All rights reserved.
Dark energy: recent observations and future prospects.

Dark energy presents us with a challenging puzzle: understanding the new physics seen in the acceleration of the expansion of the Universe. Measurements using type–Ia supernovae (SNe) first detected this acceleration, and this approach remains the most direct route to studying the details of the Universe9s expansion history that can teach us more about the nature of the dark energy. Such measurements are, however, extremely demanding in both precision and accuracy, since the different dark–energy models predict very small differences in the expansion history. While several cosmological probes may reach the required statistical uncertainties, the key measurement limit will be the systematic uncertainty. The supernova–measurement approach has the advantage of well–studied systematic uncertainties, allowing a next–generation experiment to be pursued. We briefly review the progress to date and examine the promise of future surveys with large numbers of SNe and well–bounded systematics.
Optimal number of array faces for active phased array radars

The number of array faces is an important factor in determining antenna and radar system performance, cost, and manufacturing complexity. The subject of determining the optimum number of antenna faces has been addressed previously by several authors (Knittel,1965) using various figures of merit. For active phased array radars performing tracking and discrimination functions, the important figure of merit for antenna performance is power-aperture-gain (PAG) product. We determine the optimal number of faces by choosing PAG product as the figure of merit for the same tracking and discrimination performance at maximum scan angles. Given equal antenna performance at maximum scan angles in the coverage area, cost is the primary basis for comparison in the selection of the number of faces for a modern active phased array radar system.
System and rapidity dependence of baryon to meson ratios at RHIC

The rapidity and centrality dependence of baryon to meson ratios in Au+Au, Cu+Cu and p+p collisions at s NN = 200 GeV at RHIC is presented. The p ¯ / π − ratios are found to be independent of the collision system at a fixed N part > at mid- and forward rapidities.
Improvement of LCD Viewing Angles by Negative Birefringence Compensation Films

Abstract The negative birefringence optical compensation films can be used to significantly improve the viewing angles of single-domain and multi-domain LCDs. We review the major applications of the applications of negative birefringence compensation to TN, STN, vertically aligned LCDs, and parallel aligned LCDs. Most recently, there are three TFT/LCD panels with improved large viewing cone being commercialized with the use of the negative birefringence optical compensation films. These panels include: (1). US TFT/LCD vendors compensated single domain TFT/TN panels; (2). Sharp compensated 2-domain Super-V TFT/TN panels; and (3). Fujitsu super-wide compensated 4-domain vertical aligned TFT/VA panels.
The Myth of 'Rebalancing' Retaliation in WTO Dispute Settlement Practice

It is generally assumed that trade retaliation under the WTO performs some kind of 'rebalancing' by allowing the injured Member to suspend 'concessions and obligations' vis-a-vis the violating Member of a level equivalent to the level of 'nullification and impairment' suffered by the injured Member. This article argues that this perception is misguided. The article first questions if a sensible comparator exists with which equivalence for purposes of 'rebalancing' could be evaluated. It then argues that WTO arbitration decisions do not even succeed in their limited goal of providing for retaliation that will affect trade in the same amount as the WTO-inconsistent measure at issue. One reason is the use of an asymmetric and underspecified trade effects comparator. The other reason is very significant miscalculation of the trade effects of the violation, as shown by detailed legal-economic analysis of all relevant arbitration decisions. The decisions concerning countermeasures against prohibited export subsidies do not make any attempt at 'rebalancing' in the first place. The article considers political explanations of arbitration decisions. It concludes with some suggestions for improvement. Copyright 2006, Oxford University Press.
Untestable Truths (or: Knowledge Words Can Bring)

Management research is carried out in two literary and epistemological traditions; the empirical and the conceptual. I argue that emphasizing the former to the detriment of the latter, as is often ...
User Taglines: Alternative Presentations of Expertise and Interest in Social Media

Web applications are increasingly showing recommended users from social media along with some descriptions, an attempt to show relevancy-why they are being shown. For example, Twitter search for a topical keyword shows expert twitterers on the side for `whom to follow'. Google+ and Facebook also recommend users to follow or add to friend circle. Popular Internet newspaper-The Huffing ton Post shows Twitter experts on the side of an article for authoritative relevant tweets. The state of the art shows user profile bio as summary for Twitter experts, but it has issues with length constraints imposed by the user interface (UI) design, missing bio and sometimes funny profile bio. Alternatively, applications can use human generated user summary, but it will not scale. Therefore, we study the problem of automatic generation of informative expertise summary or taglines for Twitter experts in space constraint imposed by UI design. We propose three methods for expertise summary generation: Occupation-Pattern based, Link-Triangulation based and User-Classification based, with the use of knowledge-enhanced computing approaches. We also propose methods for final summary selection for users with multiple candidates of generated summaries and evaluate results by user-study for both generation and selection tasks. The results of proposed tagline generation methods show 92.8% good summaries with majority agreement in the best case and 70% in the worst case while outperforming the state of the art up to 88%. This study has implications in the area of expert profiling, user presentation and application design for engaging user experience.
Is Jupiter's magnetosphere like a pulsar's or earth's?

Can Jupiter teach us about pulsars? The many prima facie analogies between Jupiter and pulsars — both are oblique magnetic rotators generating and containing healthy fluxes of relativistic particles, both are sources of cosmic rays and radio emissions, they even have comparable magnetic moments — make the above question an interesting one. At a deeper level, the recent Pioneer 10 encounter revealed a magnetic structure in Jupiter’s outer magnetosphere reminiscent of hydromagnetic outflow solutions postulated for pulsars (Michel, 1969, 1971) and also suggested for Jupiter (Piddington, 1969; Ioannidis and Brice, 1971; Hill et al., 1974; Michel and Sturrock, 1974).
Enrichment and pre-heating in intragroup gas from galactic outflows

We examine metal and entropy content in galaxy groups having T x ≈ 0.5-2 keV in cosmological hydrodynamic simulations. Our simulations include a well-constrained prescription for galactic outflows following momentum-driven wind scalings, and a sophisticated chemical evolution model. Our simulation with no outflows reproduces observed iron abundances in X-ray emitting gas, but the oxygen abundance is too low; including outflows yields iron and oxygen abundances in good agreement with data. X-ray measures of [O/Fe] primarily reflect metal distribution mechanisms into hot gas, not the ratio of Type Ia to Type II supernovae within the group. Iron abundance increases by ∼ x 2 from z ∼ 1 to 0 independent of group size, consistent with that seen in clusters, while [O/Fe] drops by ∼30 per cent. Core entropy versus temperature is elevated over self-similar predictions regardless of outflows due to radiative cooling removing low-entropy gas, but outflows provide an additional entropy contribution below 1 keV. This results in a noticeable break in the L x -T x relation below ∼1 keV, as observed. Entropy at R 500 is also in good agreement with data, and is unaffected by outflows. Importantly, outflows serve to reduce the stellar content of groups to observed levels. Specific energy injection from outflows drops with group mass, and exceeds the thermal energy for ≤0.5-keV systems. Radial profiles from simulations are in broad agreement with observations, but there remain non-trivial discrepancies that may reflect an excess of late-time star formation in central group galaxies in our simulations. Our model with outflows suggests a connection between physical processes of galaxy formation and both pre-heating and enrichment in intragroup gas, though more definitive conclusions must await a model that simultaneously suppresses cooling flows as observed.
Responsiveness and satisfaction with providers and carriers in a safety net insurance program: Evidence from Georgia's Medical Insurance for the Poor

Abstract Objective To evaluate provider responsiveness and beneficiary satisfaction with insurance carriers participating in the Republic of Georgia's Medical Insurance for the Poor. Study setting A dedicated survey of approximately 3500 households in two types of regions – with different eligibility thresholds – in November and December 2008. Study design Regression-based estimation of responsiveness ratings by beneficiaries and non-beneficiaries of the insurance program and estimation of mean satisfaction scores for beneficiaries. Principal findings In the high-threshold regions, provider responsiveness toward beneficiaries and non-beneficiaries is comparable. In the low-threshold regions, beneficiary status is associated with lower responsiveness of outpatient providers. Inpatient providers may have become less responsive toward beneficiaries during the program's transition from public to private administration. While satisfaction of beneficiaries with carriers is above average, there are reports of difficulties in obtaining reimbursements and information about benefits. Conclusions The results suggest that relying on private insurance companies to deliver public programs in middle-income settings may impact provider responsiveness and indicate the need for continuous monitoring and regulation.
Enveloped viruses understood via multiscale simulation: computer-aided vaccine design

Enveloped viruses are viewed as an opportunity to understand how highly organized and functional biosystems can emerge from a collection of millions of chaotically moving atoms. They are an intermediate level of complexity between macromolecules and bacteria. They are a natural system for testing theories of self-assembly and structural transitions, and for demonstrating the derivation of principles of microbiology from laws of molecular physics. As some constitute threats to human health, a computer-aided vaccine and drug design strategy that would follow from a quantitative model would be an important contribution. However, current molecular dynamics simulation approaches are not practical for modeling such systems. Our multiscale approach simultaneously accounts for the outer protein net and inner protein/genomic core, and their less structured membranous material and host fluid. It follows from a rigorous multiscale deductive analysis of laws of molecular physics. Two types of order parameters are introduced: (1) those for structures wherein constituent molecules retain long-lived connectivity (they specify the nanoscale structure as a deformation from a reference configuration) and (2) those for which there is no connectivity but organization is maintained on the average (they are field variables such as mass density or measures of preferred orientation). Rigorous multiscale techniques are used to derive equations for the order parameters dynamics. The equations account for thermal-average forces, diffusion coefficients, and effects of random forces. Statistical properties of the atomic-scale fluctuations and the order parameters are co-evolved. By combining rigorous multiscale techniques and modern supercomputing, systems of extreme complexity can be modeled.
Copolymers in dilute solution. I. Preliminary results for styrene‐methyl methacrylate

The dilute solution properties of copolymers are briefly discussed in relation to those of the parent homopolymers. It is shown that copolymer molecules are usually more expanded in solution than would be expected from the averaged behavior of the pure polymers, because of repulsive interactions between the unlike monomer units. A thermodynamic parameter χAB characterizing these interactions can be derived from measurements of the dilute solution properties of copolymers. In favorable cases this parameter can be independently evaluated from studies of ternary systems composed of the two parent homopolymers and a solvent, thus allowing prediction of the behavior of the copolymer. Light scattering and viscosity measurements on fractions of approximately equimolal copolymers of styrene and methyl methacrylate are presented and analyzed. The values of χAB deduced from the results in two solvents agree satisfactorily with each other, but are somewhat larger than those earlier obtained from measurements on ternary systems.