cssi/SciSciGPT-SciSciNet huggingface dataset:
Ligand effects in homogeneous Au catalysis.

1.1. Context and Meta-Review Despite the ubiquity of metallic gold (Au) in popular culture, its deployment in homogeneous catalysis has only recently undergone widespread investigation. In the past decade, and especially since 2004, great progress has been made in developing efficient and selective Au-catalyzed transformations, as evidenced by the prodigious number of reviews available on various aspects of this growing field. Hashmi has written a series of comprehensive reviews outlining the progression of Au-catalyzed reaction development,1 and a number of more focused reviews provide further insight into particular aspects of Au catalysis. A brief meta-review of the available range of perspectives published on Au catalysis helps to put this Chemical Reviews article in context. The vast majority of reactions developed with homogeneous Au catalysts have exploited the propensity of Au to activate carbon-carbon π-bonds as electrophiles. Gold has come to be regarded as an exceedingly mild, relatively carbophilic Lewis acid, and the broad array of newly developed reactions proceeding by activation of unsaturated carbon-carbon bonds has been expertly reviewed.2 Further reviews and highlights on Au catalysis focus on particular classes of synthetic reactions. An excellent comprehensive review of Au-catalyzed enyne cycloisomerizations is available.3 Even more focused highlights on hydroarylation of alkynes,4 hydroamination of C-C multiple bonds,5 and reactions of oxo-alkynes6 and propargylic esters7 provide valuable perspectives on progress and future directions in the development of homogeneous Au catalysis. Most of the reviews on Au catalysis emphasize broad or specific advances in synthetic utility. Recently, we have invoked relativistic effects to provide a framework for understanding the observed reactivity of Au catalysts, in order to complement empirical advancements.8 In this Chemical Reviews article, we attempt to enumerate the ways in which selectivity can be controlled in homogeneous Au catalysis. It is our hope that lessons to guide catalyst selection and the design of new catalysts may be distilled from a thorough evaluation of ligand, counterion, and oxidation state effects as they influence chemo-, regio-, and stereoselectivity in homogeneous Au catalysis.
Dynamical pion collapse and the coherence of conventional neutrino beams

In this paper we consider the coherence properties of neutrinos produced by the decays of pions in conventional neutrino beams. Using a multiparticle density matrix formalism we derive the oscillation probability for neutrinos emitted by a decaying pion in an arbitrary quantum state. Then, using methods from decoherence theory, we calculate the pion state which evolves through interaction with decay-pipe gases in a typical accelerator neutrino experiment. These two ingredients are used to obtain the distance scales for neutrino beam coherence loss. We find that for the known neutrino mass splittings, no nonstandard oscillation effects are expected on terrestrial baselines. Heavy sterile neutrinos may experience terrestrial loss of coherence, and we calculate both the distance over which this occurs and the energy resolution required to observe the effect. By treating the pion-muon-neutrino-environment system quantum mechanically, neutrino beam coherence properties are obtained without assuming arbitrary spatial or temporal scales at the neutrino production vertex.
A catalytic enantioselective synthesis of chiral monosubstituted oxiranes

Abstract A new catalytic enantioselective synthesis of monosubstituted oxiranes has been developed from achiral trichloromethyl ketones by (a) enantioselective carbonyl reduction, (b) selective bis-dechlorination and (c) base-induced ring closure of the resulting chlorohydrins.
T lymphocytes infiltrating advanced grades of cervical neoplasia. CD8-positive cells are recruited to invasion.

Background. Impaired cellular immunity appears to be a risk factor for progression of cervical neoplasia, but the immunobiology of neoplastic progression is poorly understood. The objective of this study was to characterize the subpopulations of T lymphocytes that infiltrate various grades of cervical neoplasia including metaplasia to invasive cancer in immunocompetent women. Method. In 65 patients with a spectrum of cervical disease ranging from normal cytology to carcinoma, the relative proportions of total T lymphocytes and CD4- or CD8-expressing (helper or cytotoxic) T lymphocyte subsets were determined by immunohistochemistry. Results. When the invasive carcinoma stromal infiltrate was compared with the infiltrate of preinvasive lesions, the numbers of total T cells and the CD8-positive subset increased significantly in the invasive cancers (P < 0.005). Although immunocyte infiltrates were highly concentrated in focal clusters beneath the preinvasive squamous lesions, the CD8-positive immunocytes diffusely infiltrated the invading tumor. Conclusions. The CD8-positive T cell infiltrate far exceeded the CD4-positive cells in the invasive, but not in the preinvasive lesions, a finding that suggests that CD8 cells are recruited preferentially to cervical lesions with progression to invasion.
Compact Proofs of Retrievability

In a proof-of-retrievability system, a data storage center must prove to a verifier that he is actually storing all of a client's data. The central challenge is to build systems that are both efficient and provably secure--that is, it should be possible to extract the client's data from any prover that passes a verification check. In this paper, we give the first proof-of-retrievability schemes with full proofs of security against arbitrary adversaries in the strongest model, that of Juels and Kaliski. Our first scheme, built from BLS signatures and secure in the random oracle model, features a proof-of-retrievability protocol in which the client's query and server's response are both extremely short. This scheme allows public verifiability: anyone can act as a verifier, not just the file owner. Our second scheme, which builds on pseudorandom functions (PRFs) and is secure in the standard model, allows only private verification. It features a proof-of-retrievability protocol with an even shorter server's response than our first scheme, but the client's query is long. Both schemes rely on homomorphic properties to aggregate a proof into one small authenticator value.
Fundamental Limits of Wideband Localization— Part II: Cooperative Networks

The availability of position information is of great importance in many commercial, governmental, and military applications. Localization is commonly accomplished through the use of radio communication between mobile devices (agents) and fixed infrastructure (anchors). However, precise determination of agent positions is a challenging task, especially in harsh environments due to radio blockage or limited anchor deployment. In these situations, cooperation among agents can significantly improve localization accuracy and reduce localization outage probabilities. A general framework of analyzing the fundamental limits of wideband localization has been developed in Part I of the paper. Here, we build on this framework and establish the fundamental limits of wideband cooperative location-aware networks. Our analysis is based on the waveforms received at the nodes, in conjunction with Fisher information inequality. We provide a geometrical interpretation of equivalent Fisher information (EFI) for cooperative networks. This approach allows us to succinctly derive fundamental performance limits and their scaling behaviors, and to treat anchors and agents in a unified way from the perspective of localization accuracy. Our results yield important insights into how and when cooperation is beneficial.
Directivity of bremsstrahlung radiation from relativistic beams and the gamma rays from solar flares

It has been observed that flares with greater than 10 Mev gamma-ray emission are concentrated around the solar limb with a dispersion of 10 to 20 degrees. It is shown that the bremsstrahlung by relativistic electrons is responsible for such gamma-rays and that the expected relativistic beaming cannot explain this dispersion. It is argued that this dispersion is predominately a reflection of the pitch angle distribution of the electrons. Then it is shown that this requires a small variation of the magnetic field from the point where the electrons are injected to the photosphere and a nearly isotropic (in the downward direction) pitch angle distribution at the injection. The influence of other effects on the observed distribution is also discussed.
Total synthesis of (+)-lithospermic acid by asymmetric intramolecular alkylation via catalytic C-H bond activation.

The total synthesis of (+)-lithospermic acid is described. The efficient synthesis features an asymmetric alkylation via C−H bond activation to assemble the dihydrobenzofuran core of the natural product. This was accomplished via a chiral imine-directed C−H bond functionalization and represents the first application of this C−H activation method to natural product synthesis. Furthermore, a challenging deprotection of a late-stage permethylated lithospermic acid was achieved.
The Planetary Nebula Luminosity Function at the dawn of Gaia

The [O iii] λ5007 Planetary Nebula Luminosity Function (PNLF) is an excellent extragalactic standard candle. In theory, the PNLF method should not work at all, since the luminosities of the brightest planetary nebulae (PNe) should be highly sensitive to the age of their host stellar population. Yet the method appears robust, as it consistently produces ≲10 % distances to galaxies of all Hubble types, from the earliest ellipticals to the latest-type spirals and irregulars. It is therefore uniquely suited for cross-checking the results of other techniques and finding small offsets between the Population I and Population II distance ladders. We review the calibration of the method and show that the zero points provided by Cepheids and the Tip of the Red Giant Branch are in excellent agreement. We then compare the results of the PNLF with those from Surface Brightness Fluctuation measurements, and show that, although both techniques agree in a relative sense, the latter method yields distances that are ∼15 % larger than those from the PNLF. We trace this discrepancy back to the calibration galaxies and argue that, due to a small systematic error associated with internal reddening, the true distance scale likely falls between the extremes of the two methods. We also demonstrate how PNLF measurements in the early-type galaxies that have hosted Type Ia supernovae can help calibrate the SN Ia maximum magnitude-rate of decline relation. Finally, we discuss how the results from space missions such as Kepler and Gaia can help our understanding of the PNLF phenomenon and improve our knowledge of the physics of local planetary nebulae.
Codebook-based audio feature representation for music information retrieval

Digital music has become prolific in the web in recent decades. Automated recommendation systems are essential for users to discover music they love and for artists to reach appropriate audience. When manual annotations and user preference data is lacking (e.g. for new artists) these systems must rely on content based methods. Besides powerful machine learning tools for classification and retrieval, a key component for successful recommendation is the audio content representation. Good representations should capture informative musical patterns in the audio signal of songs. These representations should be concise, to enable efficient (low storage, easy indexing, fast search) management of huge music repositories, and should also be easy and fast to compute, to enable real-time interaction with a user supplying new songs to the system. Before designing new audio features, we explore the usage of traditional local features, while adding a stage of encoding with a pre-computed codebook and a stage of pooling to get compact vectorial representations. We experiment with different encoding methods, namely the LASSO, vector quantization (VQ) and cosine similarity (CS). We evaluate the representations' quality in two music information retrieval applications: query-by-tag and query-by-example. Our results show that concise representations can be used for successful performance in both applications. We recommend using top-τ VQ encoding, which consistently performs well in both applications, and requires much less computation time than the LASSO.
Decentralized robust control design with insufficient number of controllers

The paper studies the decentralized robust stabilization problem for a large-scale system which is composed of three subsystems. Each subsystem may contain nonlinear and/or time-varying uncertainties and interconnections; but one of these subsystems does not have direct control. We demonstrate a control design procedure where the interconnection characteristic is fully utilized. By showing that it is possible to use the interconnection as a bridge to convey the influence of control, decentralized controls can be designed.
Fast computation with neural oscillators

This paper studies new spike-based models for winner-take-all computation and coincidence detection. In both cases, fast convergence is achieved independent of initial conditions, and network complexity is linear in the number of inputs. Fully distributed versions can be modelled based on groups of interneurons connected through electrical synapses.
Distribution of Particles Which Produces a "Smart" Material

If Aq(β, α, k) is the scattering amplitude, corresponding to a potential \( q\in L^2(D) \), where D⊂ℝ3 is a bounded domain, and \( e^{ik\alpha \cdot x} \) is the incident plane wave, then we call the radiation pattern the function \( A(\beta):=A_q(\beta, \alpha, k) \), where the unit vector α, the incident direction, is fixed, β is the unit vector in the direction of the scattered wave, and k>0, the wavenumber, is fixed. It is shown that any function \( f(\beta)\in L^2(S^2) \), where S2 is the unit sphere in ℝ3, can be approximated with any desired accuracy by a radiation pattern: \( ||f(\beta)-A(\beta)||_{L^2(S^2)} 0 is an arbitrary small fixed number. The potential q, corresponding to A(β), depends on f and ∊, and can be calculated analytically. There is a one-to-one correspondence between the above potential and the density of the number of small acoustically soft particles Dm⊂ D, 1≤ m≤ M, distributed in an a priori given bounded domain D⊂ℝ3. The geometrical shape of a small particle Dm is arbitrary, the boundary Sm of Dm is Lipschitz uniformly with respect to m. The wave number k and the direction α of the incident upon D plane wave are fixed. It is shown that a suitable distribution of the above particles in D can produce the scattering amplitude \( A(\alpha',\alpha)$, $\alpha',\alpha\in S^2 \), at a fixed k>0, arbitrarily close in the norm of L2(S2× S2) to an arbitrary given scattering amplitude f(α ', α), corresponding to a real-valued potential q∊ L2(D), i.e., corresponding to an arbitrary refraction coefficient in D.
Dark matter near the sun

The amount of dark matter in the disk of the Galaxy at the solar position is determined by comparing the observed distributions of tracer stars with the predictions obtained from different assumptions of how the unseen matter is distributed. The major uncertainties, observational and theoretical, are estimated. For all the observed samples, typical models imply that about half of the mass in the solar vicinity must be in the form of unobserved matter. The volume density of unobserved material near the sun is about 0.1 solar mass/cu pc; the corresponding column density is about 30 solar masses/cu pc. This, so far unseen, material must be in a disk with an exponential scale height of less than 0.7 kpc. All the existing observations are consistent with the unseen disk material being in the form of stars not massive enough to burn hydrogen. It is suggested that the unseen material that is required to hold up the rotation curves of galaxies and to satisfy the virial theorem for clusters of galaxies might also be in the form of low-mass stars.
Substrate creep on the fatigue life of a model dental multilayer structure.

In this article, we investigated the effects of substrate creep on the fatigue life of a model dental multilayer structure, in which a top glass layer was bonded to a polycarbonate substrate through a dental adhesive. The top glass layers were ground using 120 or 600 grit sand papers before bonding to create different subsurface crack sizes and morphologies. The multilayer structures were tested under cyclic Hertzian contact loading to study crack growth and obtain fatigue life curves. The experiment results showed that the fatigue lives of the multilayer structures were impaired by increasing crack sizes in the subsurfaces. They were also significantly reduced by the substrate creep when tested at relatively low load levels, i.e. Pm 65 N, slow crack growth was the major failure mechanism. A modeling study was then carried out to explore the possible failure mechanisms over a range of load levels. It is found that fatigue life at relatively low load levels can be better estimated by considering the substrate creep effect. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007
Nonsymmetric difference Whittaker functions

Starting with nonsymmetric global difference spherical functions, we define and calculate spinor (nonsymmetric) global $$q$$ -Whittaker functions for arbitrary reduced root systems, which are reproducing kernels of the DAHA-Fourier transforms of Nil-DAHA and solutions of the $$q$$ -Toda–Dunkl eigenvalue problem. We introduce the spinor $$q$$ -Toda–Dunkl operators as limits of the difference Dunkl operators in DAHA theory under the spinor variant of the Ruijsenaars procedure. Their general algebraic theory (any reduced root systems) is the key part of this paper, based on the new technique of $$W$$ -spinors and corresponding developments in combinatorics of affine root systems.
Vortices near the Mott phase of a trapped Bose-Einstein condensate

We present a theoretical study of vortices within a harmonically trapped Bose-Einstein condensate in a rotating optical lattice. We find that proximity to the Mott insulating state dramatically affects the vortex structures. To illustrate, we give examples in which the vortices (i) all sit at a fixed distance from the center of the trap, forming a ring, or (ii) coalesce at the center of the trap, forming a giant vortex. We also model time-of-flight expansion.
Can a charged ring levitate a neutral polarizable object? Can earnshaw's theorem be extended to such objects?

Stable electrostatic levitation and trapping of a neutral polarizable object by a charged ring is shown to be theoretically impossible. Earnshaw’s theorem precludes the existence of such a stable neutral particle trap.
Granular gravitational collapse and chute flow

We argue that inelastic grains in a flow under gravitation tend to collapse into states in which the relative normal velocities of two neighboring grains is zero. If the time scale for this gravitational collapse is shorter than inverse strain rates in the flow, we propose that this collapse will lead to the formation of granular eddies, large-scale condensed structures of particles moving coherently with one another. The scale of these eddies is determined by the gradient of the strain rate. Applying these concepts to chute flow of granular media (gravitationally driven flow down inclined planes), we predict the existence of a bulk flow region whose rheology is determined only by flow density. This theory yields the Pouliquen flow rule, correlating different chute flows; it also accounts for the different flow regimes observed.
Modeling well performance for fractured horizontal gas wells

Abstract In tight gas reservoirs, horizontal wells have been used to increase reservoir recovery and hydraulic fracturing has been applied to further extend the contact with the reservoir. In the past, many models, analytical or numerical, were developed to describe the flow behavior in horizontal wells with fractures. Source solution is one of analytical/semi-analytical approaches. The source method was advanced from point sources to volumetric source, and pressure change inside fractures was considered in the volumetric source method. We have developed a method that can predict horizontal well performance, and the model can also be applied to fractured horizontal wells. The method solves the problem by superposing a series of slab sources under transient or pseudo-steady state flow conditions. The principle of the method comprises the calculation of semi-analytical response of a rectilinear reservoir with closed outer boundaries. The slab source approach assigns sources a geometry dimension, similar to the volumetric source method; but has the solution similar to the point source method by neglecting the effect of the flow inside the source. When solving the source problem the pressure/flow effect inside source is considered sequentially by superposition principle over multiple sources. The pressure response is integrated over time to provide continuous pressure behavior. Flow effect inside fractures can be studied by dividing the fracture into several segments, and each can be treated as a slab source. The method is validated by comparison with the results of analytical solutions and other commercial software of horizontal wells with uniform flux and infinite conductivity, and fractured wells with uniform flux, finite or infinite conductivity. For multiple fractures in a horizontal well, the method was also compared with some published field data. The method provides an effective tool for horizontal well design and well stimulation design for gas reservoirs. In this paper, we present the details of model development. We use a case study to illustrate how the model can help to optimize wellbore and fracture design by comparing production performances of vertical well, slanted well, horizontal well, and fractured vertical and horizontal wells. The method in this paper is more accurate compared with conventional point-source solution, and can handle the transaction from transient flow to pseudo-steady state flow smoothly.
REINDUSTRIALIZATION OF AMERICA

If the United States is to sustain a fairly high level of economic growth, seven functional needs must be met: transportation, communication, power, innovation, human resources, financialbegal institutions, and capital goods. Attention to these elements amounted for the successful development of the infrastructure and the capital goods sector during America's first industrialization, roughly from the 1820s to the 1920s, providing the foundation for a strong economy able to mass-produce consumer goods and services. In the decades following World War II, however, roughly from 1950 to the late 1970s, insufficient resources were dedicated to maintaining and adapting these seven elements, and in varying degrees all but one deteriorated. The result was economic underdevelopment. For the United States to regain i t s economic vitality, steps must now be taken to serve these basic needs of economic development more effectively.
Quasi-steady plasma acceleration.

Applications of quasi-steady state plasma acceleration to development of pulsed plasma jet engines
Design and Analysis of a Hybrid Access Control to an Optical Star Using WDM

A passive optical star is an ideal shared medium, from both fault tolerant and access synchronization points of view. The communication over an optical star merges to a single point in space and then broadcasts back to all the nodes. This circular symmetry facilitates the solution for two basic distributed synchronization problems, which are presented in this work: (i) the generation of a global event clock for synchronizing the nodes?operation, and (ii) distributed scheduling for accessing the shared passive medium, which is a hybrid (deterministic and random) technique. We present, prove, and analyze this hybrid scheduling algorithm, which is equivalent to a distributed queue, and, therefore, is also algorithmically fair. Furthermore, our solution has two additional properties: destination overflow prevention and destination fairness. The effective solution of these problems can be used for efficiently implementing a local area network based on a passive optical star.
To obtain or not to obtain CSI in the presence of hybrid adversary

We consider the wiretap channel model under the presence of a hybrid, half duplex adversary that is capable of either jamming or eavesdropping at a given time. We analyzed the achievable rates under a variety of scenarios involving different methods for obtaining transmitter CSI. Each method provides a different grade of information, not only to the transmitter on the main channel, but also to the adversary on all channels. Our analysis shows that main CSI is more valuable for the adversary than the jamming CSI in delay-limited scenarios. Similarly, in certain cases under the ergodic scenario, interestingly, no CSI may lead to higher achievable secrecy rates than with CSI.
Mechanisms of metal-catalyzed dehydrocoupling reactions

This review summarizes selected mechanistic insight garnered from reactions that form bonds between main group elements with liberation of hydrogen, dehydrocoupling or dehydropolymerization reactions. Focus has been made where mechanistic study has been done or provides unique insight as compared to previous work. Thus, a limited number of catalysts and substrates will be discussed, but a broad range of mechanistic features will be noted. A comparative approach considering dehydrocoupling reactions that appear to proceed by certain mechanistic steps is taken here, beginning with steps that are well established and general then moving to those that are newer, at least to this application.
Automatic gain control of transistor amplifiers

Due to the dependence of transistor small signal parameters on the dc operating point, the gain of a transistor amplifier is function of the emitter current Ie and of the collector voltage Vc. An analysis of the variation of the series-parallel transistor parameters hij with the operating point shows that the gain decreases with decreasing Ie or decreasing Vc in the region of small values of Ie and Vc. The appreciable control power necessary to vary Ie or Vc (of possibly several amplifying stages) can be obtained advantageously by operating the controlled stages as dc amplifiers of the control signal and employing transistor detectors. Automatic gain control systems applicable to linear amplifiers and converters using Ie and Vc control have been developed, and their performance is described in this paper. Some problems arising in-transistor AGC systems are distortion, detuning and bandwidth variation.
A viscoelastic representation of the mechanical behavior of RVD graphite at elevated temperatures

Abstract A set of constitutive equations is developed to describe the time-dependent mechanical behavior of RVD graphite at temperatures from 3500 to 5000°F. The relations are based upon a transversely isotropic linear viscoelastic model with temperature-dependent parameters. This model is shown to be applicable for stress levels up to one-half the nominal ultimate stress values for the material. Predictions of these equations are compared with experimental measurements from short-time stress-strain tests, creep tests, and relaxation tests.
Gas-phase first bond dissociation energies in transition-metal carbonyls

Abstract Bond dissociation energy values for a group of transition-metal carbonyl compounds and derivatives in the gas phase are given and discussed. Metals include Fe, Cr, Mo, W and Mn. New preliminary values of 38 and 44 kcal mol−1 are reported for Mn2(CO)9CO and MnBr(CO)4CO.
Robust confidence sets in the presence of weak instruments

Abstract This paper considers instrumental variable regression with a single endogenous variable and the potential presence of weak instruments. I construct confidence sets for the coefficient on the single endogenous regressor by inverting tests robust to weak instruments. I suggest a numerically simple algorithm for finding the Conditional Likelihood Ratio (CLR) confidence sets. Full descriptions of possible forms of the CLR, Anderson–Rubin (AR) and Lagrange Multiplier (LM) confidence sets are given. I show that the CLR confidence sets have nearly the shortest expected arc length among similar symmetric invariant confidence sets in a circular model. I also prove that the CLR confidence set is asymptotically valid in a model with non-normal errors.
Image Quality Assessment: How Blind is Blind?

I will consider some of the factors to be considered when assessing the capability and limitations of a new imaging modality, using holography in the 60's and 70's as an example. Biography (100 word limit): Joseph W. Goodman received an A.B. Degree from Harvard, an M.S degree and a Ph.D. degree, both from Stanford University. He joined the faculty of the Department of Electrical Engineering at Stanford in 1967, chaired the department from 1989 to 1996, and served as Senior Associate Dean of Engineering until 1999. He retired from Stanford in January of 2001. Dr. Goodman is the author of the books Introduction to Fourier Optics (now in its 3 rd edition), Statistical Optics, Speckle Phenomena in Optics. He has received numerous awards from the I.E.E.E., the A.S.E.E., the O.S.A., the S.P.I.E ., including the highest awards given by the latter two societies.Blind Image Quality Assessment (Blind IQA) is usually synonymous with
TOWARDS BALLISTIC TRANSPORT IN GRAPHENE

Graphene is a fascinating material for exploring fundamental science questions as well as a potential building block for novel electronic applications. In order to realize the full potential of this material the fabrication techniques of graphene devices, still in their infancy, need to be refined to better isolate the graphene layer from the environment. We present results from a study on the influence of extrinsic factors on the quality of graphene devices including material defects, lithography, doping by metallic leads and the substrate. The main finding is that trapped Coulomb scatterers associated with the substrate are the primary factor reducing the quality of graphene devices. A fabrication scheme is proposed to produce high quality graphene devices dependably and reproducibly. In these devices, the transport properties approach theoretical predictions of ballistic transport.
Exploring expert and novice mental models of phishing

Mental models are internal representations of a concept or system that develop with experience. By rating pairs of concepts on the strength of their relationship, networks can be created showing an in-depth analysis of how information is organized. We asked novice and expert computer users to rate 10 terms related to the prevention of phishing. Expert mental models were more complex with more links between concepts. Relatedness ratings provide quantifiable network displays of mental models of novices and experts that cannot be seen through interviews. This information could provide a basis for future research on how mental models could be used to determine phishing vulnerability and the effectiveness of phishing training.
Solving linear recurrences with loop raking

Abstract We present a variation of the partition method for solving linear recurrences that is well-suited to vector multiprocessors. The algorithm fully utilizes both vector and multiprocessor capabilities, and reduces the number of memory accesses and temporary memory requirements as compared to the more commonly used version of the partition method. Our variation uses a general loop restructuring technique called loop raking. We describe an implementation of this technique on the CRAY Y-MP C90, and present performance results for first- and second-order linear recurrences. On a single processor of the C90 our implementations are up to 7.3 times faster than the corresponding optimized library routines in SCILIB, an optimized mathematical library supplied by Cray Research. On four processors, we gain an additional speedup of at least 3.7.
Multiple agent-based autonomy for satellite constellations

Multiple, highly autonomous, satellite systems are envisioned in the near future because they are capable of higher performance, lower cost, better fault tolerance, reconfigurability and upgradability. This paper presents an architecture and multi-agent design and simulation environment that will enable agent-based multi-satellite systems to fulfill their complex mission objectives, termed ObjectAgentTM. Its application is shown for a distributed aperture radar mission, although its applicability spans many types of missions. Required spacecraft functions, software agents, and multi-agent organisations are described for the radar mission, as well as their implementation. Agent-based simulations of mission case studies show the autonomous operation of the multi-agent architecture, which can then be used to build, evaluate and compare autonomous software architectures for multiple satellite systems.
Thermal conductivity of a thermosetting advanced composite during its cure

The thermal conductivity of a thermosetting advanced composite material during its cure was experimentally investigated and compared to analytical models. The thermal conductivity of graphite/epox y was experimentally measured using a guarded hot plate apparatus. The through-thickness transverse thermal conductivity of composite laminates was measured at various resin degrees of cure and fiber volume fractions while using various ply lay-up angles. The in-plane thermal conductivity was measured using unidirectional laminates, as well as laminates with various ply lay-up angles. Techniques for manufacturing composite laminates with these various properties, as well as the guarded hot plate apparatus necessary for accurate measurements, are described. Finally, various analytical models were researched, and those that compare most favorably with the experimental data are presented. Nomenclature Hc = thermal contact conductance of the experiment, W/m2°C Hr = resin heat of reaction for AS4/3501-6, J/g K = thermal conductivity, W/m°C L = laminate dimension in the x direction, m N = number of plies in a laminate p = function of the fiber volume fraction, Eq. (6) Q = total heat flux, W q = heat flux/area, W/m2 q = resin energy generation rate per unit volume, W/m3 qln = heat flux/area applied by the guarded hot plate,
Synthesis, crystal structure, infrared and electrical conductivity of the layered rubidium uranate Rb4U5O17

Abstract Single crystals of a new layered rubidium uranate compound Rb 4 U 5 O 17 have been synthesized by high-temperature solid-state reaction. The crystal structure was determined from single crystal X-ray diffraction data. The title compound crystallizes in the orthorhombic symmetry with space group Pbcn , and the following crystallographic data: a = 18.6762(9) A, b = 7.0490(4) A, c = 14.1207(7) A and Z = 4. A full-matrix least-squares refinement on the basis of F 2 yielded R 1 = 0.031 and w R 2 = 0.060 for 120 parameters with 2723 independent reflections with I ≥ 2 σ ( I ) collected on a BRUKER X8 Apex II 4K diffractometer with Mo Kα radiation and a CCD detector. The crystal structure contains infinite corrugated layers [ ( U O 2 ) 5 O 7 ] 4 − parallel to (0 0 1), formed by the association by edge- and corner-sharing of (UO 2 )O 5 pentagonal bipyramids and distorted (UO 2 )O 4 square bipyramids. The alkaline cation Rb + are localized between layers and ensured the cohesion of the structure. Conductivity measurements, between 200 and 700 °C, show an Arrhenius law evolution, with a better electrical conductivity than the two other uranates Rb 9 U 9 O 31 and Rb 2 U 2 O 7 , recently characterized. Infrared spectroscopy measurements at room temperature have allowed the identification of the various modes of vibrations of the uranyl ions.
Effects of electric microfields on argon dielectronic satellite spectra in laser-produced plasmas

Theoretical spectral-line profiles have been obtained for dielectronic satellite transitions in heliumlike and lithiumlike argon ions. Particular emphasis has been given to the systematic and self-consistent incorporation of the non-local-thermodynamic-equilibrium autoionizing-level populations, together with the line-broadening effects, which are due to autoionization processes, radiative transitions, electron collisions, and the action of the plasma ion-produced electric microfields. An investigation has been carried out of the effects of the plasma electric microfields on predicted dielectronic satellite line-intensity ratios, and a discussion is presented on the consequences of the electric-microfield effects for the spectroscopic determination of basic physical properties in laser-produced plasmas.
A Scalable SCR Compact Model for ESD Circuit Simulation

A scalable compact model for SCR-based electrostatic discharge (ESD) protection devices is presented. This model captures the effect that layout spacing has on SCR characteristics, such as holding voltage and trigger current. The model also captures both the delayed turn-on of the SCR, which results in large voltage overshoots during fast rise-time ESD events and the charge removal mechanisms that underlie the turn-off transient. Bias and time dependences of SCR on-resistance are captured with a resistance model that accounts for self-heating.
What's So Funny About Arguing with God? A Case for Playful Argumentation from Jewish Literature

In this paper, we show that God is portrayed in the Hebrew Bible and in the Rabbinic literature—some of the very Hebrew texts that have influenced the three major world religions of Judaism, Christianity, and Islam—as One who can be argued with and even changes his mind. Contrary to fundamentalist positions, in the Hebrew Bible and other Jewish texts God is omniscient but enjoys good, playful argumentation, broadening the possibilities for reasoning and reasonability. Arguing with God has also had a profound influence upon Jewish humor, demonstrating that humans can joke with God. More specifically, we find in Jewish literature that humor’s capacity to bisociate between different domains of human experience can share a symbiotic relationship with argumentation’s emphasis on producing multiple, contested perspectives. Overall, once mortals realize that figures such as God can accept many perspectives through humor, teasing, arguing, criticism, and in at least one case, even lawsuits, a critical point emerges: citizens should learn to live, laugh, and reason with others with whom they disagree.
Invasion waves in the presence of a mutualist

This paper studies invasion waves in the diffusive competitor–competitor–mutualist model generalizing the two-species Lotka–Volterra model studied by Weinberger et al. The mutualist may benefit the invading or the resident species producing two different types of invasions. Sufficient conditions for linear determinacy are derived in both cases, and when they hold, explicit formulas for linear spreading speeds of the invasions are obtained by linearizing the model. While in the first case the linear speed is increased by the mutualist, it is unaffected in the second case. Mathematical methods are based on converting the model into a cooperative reaction–diffusion system. Copyright © 2013 John Wiley & Sons, Ltd.
Ligand-Promoted C-3 Selective C–H Olefination of Pyridines with Pd Catalysts

Pd-catalyzed C-3 selective olefination of pyridines is developed for the first time using 1,10-phenanthroline as the ligand. This finding provides a novel disconnection for the synthesis of pyridine-containing alkaloids and drug molecules as well as a new approach for developing Pd-catalyzed C-H functionalizations of pyridines.
Facile Access to Sterically Hindered Aryl Ketones via Carbonylative Cross-Coupling: Application to the Total Synthesis of Luteolin.

A general and mild protocol for achieving the carbonylative cross-coupling of sterically hindered, ortho-disubstituted aryl ketones is reported. The commercially available PEPPSI-IPr catalyst is shown to efficiently promote the carbonylative cross-coupling of hindered ortho-disubstituted aryl iodides to give diaryl ketones; traditional phosphine catalysts are less effective. Carbonylative Suzuki-Miyaura cross-couplings provide a diverse array of biaryl ketones in good to excellent yields. The same catalyst is also shown to catalyze a carbonylative Negishi cross-coupling reaction, utilizing a variety of alkynyl-zinc reagents to give the corresponding alkynyl aryl ketones. Application of this new methodology to the synthesis of the natural product luteolin is reported.
Septal stimulation for the initiation of heterosexual behavior in a homosexual male

Abstract A 24-year-old male, overt homosexual, repeatedly hospitalized for chronic suicidal depression and found to have temporal lobe epilepsy, underwent a program of septal stimulation which resulted in subjectively reported and behaviorally observed states of pleasure, euphoria, relaxation, confidence, and sexual motivation. These responses were subsequently used to initiate heterosexual arousal and behavior. The findings have important implications for the treatment of some psychological disorders.
Evidence for Antipodal Hot Spots During X-Ray Bursts from 4U 1636–536

The discovery of high-frequency brightness oscillations in thermonuclear X-ray bursts from several neutron star low-mass X-ray binaries has important implications for the beat frequency model of kilohertz quasi-periodic brightness oscillations, the propagation of nuclear burning, the structure of the subsurface magnetic fields in neutron stars, and the equation of state of high-density matter. These implications depend crucially on whether the observed frequency is the stellar spin frequency or its first overtone. Here we report an analysis of five bursts from 4U 1636-536 that exhibit strong oscillations at ~580 Hz. We show that combining the data from the first 0.75 s of each of the five bursts yields a signal at ~290 Hz that is significant at the 4×10−5 level when the number of trials is taken into account. This strongly indicates that ~290 Hz is the spin frequency of this neutron star and that ~580 Hz is its first overtone, in agreement with other arguments about this source but in contrast to suggestions in the literature that ~580 Hz is the true spin frequency. The method used here, which is similar to matched filtering, may be used for any source to search for weak oscillations that have frequencies related in a definite way to the frequency of a strong oscillation.
Stable stationary processes related to cyclic flows

We study stationary stable processes related to periodic and cyclic flows in the sense of Rosinski [Ann. Probab. 23 (1995) 1163–1187]. These processes are not ergodic. We provide their canonical representations, consider examples and show how to identify them among general stationary stable processes. We conclude with the unique decomposition in distribution of stationary stable processes into the sum of four major independent components: 1. A mixed moving average component. 2. A harmonizable (or “trivial”) component. 3. A cyclic component 4. A component which is different from these.
Liaison addition and the structure of a Gorenstein liaison class

We study the concept of liaison addition for codimension two subschemes of an arithmetically Gorenstein projective scheme. We show how it relates to liaison and biliaison classes of subschemes and use it to investigate the structure of Gorenstein liaison equivalence classes, extending the known theory for complete intersection liaison of codimension two subschemes. In particular, we show that on the non-singular quadric threefold in projective 4-space, every non-licci ACM curve can be obtained from a single line by successive liaison additions with lines and CI-biliaisons.
Ruthenium(II) complexes of tetra-2-pyridyl-1,4-diazine

Abstract Tetra-2-pyridyl-1,4-diazine (TPD) reacts with one equivalent of Ru(tpy)Cl3 to provide (tpy)Ru(TPD)2+ which when treated with a second equivalent of Ru(tpy)Cl3 under more forcing conditions provides the TPD bridged binuclear complex, (tpy)Ru(TPD)Ru(tpy)4+. The structure of both complexes, particularly with regard to planarity of the pendant pyridine rings is analyzed by high field NMR. The electronic spectrum of the binuclear complex shows pronounced bathochromic shift, while the redox potentials for (tpy)Ru(TPD)2+. indicate a diminished HOMO-LUMO energy gap.
Long-Term Effects of Zinc Exposures on Brook Trout (Salvelinus fontinalis)

Abstract Exposure of three generations of brook trout (Salvelinus fontinalis) to zinc concentrations ranging from 2.6 to 534 μg/liter produced no significant harmful effects. During a separate exposure of embryos and larvae, 1,368 μg Zn/liter significantly reduced (P = 0.05) both embryo and 12-week larval survival. An additional partial chronic exposure also resulted in significantly reduced (P = 0.05) egg chorion strength and embryo survival at 1,360 μg Zn/liter. The maximum acceptable toxicant concentration (MATC) for brook trout exposed to zinc in Lake Superior water (hardness = 45.4 mg/liter as CaCO3; pH = 7.0–7.7) lies between 534 and 1,360 μg Zn/liter. The 96-hour LC50 (median lethal) concentration for brook trout was 2,000 μg Zn/liter; thus the application factor (MATC/96-hour LC50) lies between 0.267 and 0.680. Brook trout gill, liver, kidney, and opercular bone tissues accumulated the greatest amounts of zinc. Edible muscle tissue did not accumulate zinc. Zinc loss from gill and liver from first-...
Economic tradeoff between biochar and bio-oil production via pyrolysis

This paper examines some of the economic tradeoffs in the joint production of biochar and bio-oil from cellulosic biomass. The pyrolysis process can be performed at different final temperatures, and with different heating rates. While most carbonization technologies operating at low heating rates (large biomass particles) result in higher yields of charcoal, fast pyrolysis (which processes small biomass particles) is the preferred technology to produce bio-oils. Varying operational and design parameters can change the relative quantity and quality of biochar and bio-oil produced for a given feedstock. These changes in quantity and quality of both products affect the potential revenue from their production and sale. We estimate quadratic production functions for biochar and bio-oil. The results are then used to calculate a product transformation curve that characterizes the yields of bio-oil and biochar that can be produced for a given amount of feedstock, movement along the curve corresponds to changes in temperatures, and it can be used to infer optimal pyrolysis temperature settings for a given ratio of biochar and bio-oil prices.
Thermal promotion of the cobalt catalyzed intramolecular Pauson-Khand reaction — An alternative experimental protocol for cyclopentenone synthesis

Abstract Heat alone has been found sufficient to promote intramolecular Pauson-Khand cyclizations catalyzed by high purity Co 2 (CO) 8 . The existence of a very narrow thermal window (e.g., 60 °C – 70 °C) for the attainment of efficient catalysis is a noteworthy characteristic of this process.
An experimental study of the Saffman-Taylor instability

When a gas is pushed into a viscous fluid through a Hele-Shaw cell, one observes, after a long transient, the formation of a finger which propagates steadily along the channel. This simple situation defines the Saffman Taylor1 problem. In spite of its simplicity, the limiting sizes of those fingers at large velocities and their stability has not been understood for a long time. A particularly striking fact observed in the experiments is that fingers occupy about one-half of the channel width at large velocities. In the model of Saffman and Taylor1, where surface tension is neglected, all finger sizes are allowed. Moreover, fingers of size 1/2 are found linearly unstable, which is also in direct conflict with experiment. The problem was then to understand how surface tension acts to select finger sizes and to ensure stability.