cssi/SciSciGPT-SciSciNet huggingface dataset:
Solution of the Time-Dependent Navier-Stokes Equations for the Flow around a Circular Cylinder

Traditionally, aerodynamicists, in order to simplify the theoretical treatment of determining the flowfield around an object, have developed special methods for treating the various viscous and relatively inviscid zones of the flow, including the shock wave, the shock layer, the boundary layer, and the wake. Thus the total flowfield has generally been obtained by "patchwork." Although the foregoing approach certainly yields useful information, it is desirable to develop a method of solving the complete Navier-Stokes equations in which no such arbitrary assumptions are made. In the present paper, the authors present numerical solutions to the complete time-dependent Navier-Stokes equations for the transient supersonic flow around a right circular cylinder. The nonlinear partial differential equations for the conservation of mass, momentum, and energy were first expressed in cylindrical coordinates and then put into finite-difference form, making use of a new explicit-implicit, finitedifference scheme. These were analyzed for stability and convergence, and specific criteria were established for determining step sizes. Finally, numerical solutions were obtained for several Reynolds numbers for a freestream velocity of 10,000 fps.
The Infrared Counterpart of the Microquasar GRS 1758–258

We present revised infrared (2.2 μm) astrometry of the field containing the Galactic microquasar GRS 1758-258, using observations at the Keck I 10 m telescope. We find three candidates for the microquasar within a 3 σ error circle but none within 2 σ. We show that if the 18.4 day X-ray period of GRS 1758-258 is due to a binary orbit, then only one of the three candidates, an early K-type giant, is large enough to power the microquasar via Roche lobe overflow. We therefore identify this star as the infrared counterpart of GRS 1758-258, which we classify as a low-mass X-ray binary. Long-term infrared monitoring of this source should provide further information about the microquasar system, including a confirmation of the X-ray period and an estimate of the compact object's mass.
Exploring Halo Substructure with Giant Stars: Spectroscopy of Stars in the Galactic Anticenter Stellar Structure

To determine the nature of the recently discovered, ringlike stellar structure at the Galactic anticenter, we have collected spectra of a set of presumed constituent M giants selected from the Two Micron All Sky Survey Point Source Catalog. Radial velocities have been obtained for stars spanning ~100°, exhibiting a trend in velocity with Galactic longitude and an estimated dispersion of σv = 20 ± 4 km s-1. A mean metallicity [Fe/H] = -0.4 ± 0.3 measured for these stars combines with previous evidence from the literature to suggest a population with a significant metallicity spread. In addition, a curious alignment of at least four globular clusters of lower mean metallicity is noted to be spatially and kinematically consistent with this stellar distribution. We interpret the M giant sample position and velocity variation with Galactic longitude as suggestive of a satellite galaxy currently undergoing tidal disruption in a noncircular, prograde orbit about the Milky Way.
IRREGULARIDAD, INVALIDEZ E INEFICACIA EN EL CONTEXTO DE LA NULIDAD PROCESAL

This article aims to propose some conceptual bases that are useful to understand the nullity in a civil proceeding. To this effect, three concepts are distinguished and analyzed: irregularity, invalidity and ineffectiveness, that describe the defective way of a procedural act, since it is determined that it does not correspond with the prototype model granted by the legal system until it becomes ineffective. The nullity is understood as a technique used to render ineffective acts issued by the court, usually but not exclusively, due to its invalidity and it should be used only in case of the non working ratification or correction of the defective procedural act.
Quark-hadron and chiral transitions and their relation to the early universe

Abstract A review is made of the relation of the quark-hadron and chiral symmetry transitions and the big bang universe. Possible signatures at de-confinement are mentioned and related to cosmology. It is noted that to produce surviving perturbations at this epoch requires black hole production which in turn would require a first-order phase transition. The effect of a quark matter phase in neutron stars is also discussed and related to monopole flux limits through its role in cooling.
A three-dimensional quantum simulation of silicon nanowire transistors with the effective-mass approximation

The silicon nanowire transistor (SNWT) is a promising device structure for future integrated circuits, and simulations will be important for understanding its device physics and assessing its ultimate performance limits. In this work, we present a three-dimensional (3D) quantum mechanical simulation approach to treat various SNWTs within the effective-mass approximation. We begin by assuming ballistic transport, which gives the upper performance limit of the devices. The use of a mode space approach (either coupled or uncoupled) produces high computational efficiency that makes our 3D quantum simulator practical for extensive device simulation and design. Scattering in SNWTs is then treated by a simple model that uses so-called Buttiker probes, which was previously used in metal-oxide-semiconductor field effect transistor simulations. Using this simple approach, the effects of scattering on both internal device characteristics and terminal currents can be examined, which enables our simulator to be used f...
IS AGRICULTURAL RESEARCH STILL A PUBLIC GOOD

Biotechnology is redefining the nature of agricultural research and intellectual property. In response, public agricultural research institutions are increasingly protecting their intellectual property and commercializing research results. This raises the question: Is agricultural research still a public good? This paper is a critical first step in understanding how increasingly private ownership of intellectual property affects the agribusiness environment and the evolving role of public agricultural research institutions. The innovative step is the development of a neo-Schumpeterian model which examines whether commercialization of public research maximizes social welfare. The model contains two types of research firms: large firms such as the major life-science companies; and small university-related firms (SMURFs). Results show that both large firms and SMURFs underinvest in research relative to the social optimum, that research investment can exhibit cyclical behavior, and that there is a continued, albeit diminished, role for public agricultural research as the life-science revolution progresses. [JEL Classifications: Q13, O34, L10] © 2000 John Wiley & Sons, Inc.
Maturational changes in testicular steroidogenesis: Hormonal regulation of 5α-reductase

Abstract Studies were undertaken to compare the capacity of the human and rat testis to convert progesterone-3H (3H-P) both to testosterone (T) and 5α-androstane-3α,17β-diol (5α-diol) at various stages of development, and to determine the possible mechanisms regulating the maturational changes in 5a-reductase activity in the rat testis. Testes from 1- and 13-yr-old males converted 3H-P to T (7–13%) and 17-hydroxyprogesterone (3–20%) and several unidentified metabolites. A similar metabolic pattern was obtained when 3H-P was incubated with testicular homogenate of 20-yr-old subjects, with the exception that the formation of T (27%) was higher than in 13-yr-old testis. Very little 5α-reduced androstane products, however, accumulated in these three incubations. Under the same incubation conditions, 90-day-old rat testis converted 3H-P to T, while 28-day-old testis converted 3H-P mainly to 5α-diol (58%). To determine whether 5α-reductase activity is dependent on gonadotropic stimulation, 5α-reductase was measured in seminiferous tubules and interstitial cells following various periods of hypophysectomy. In both testicular compartments, 5α-reductase activity decreased rapidly, reaching a minimal level 7 days following hypophysectomy. Treatment with either FSH or LH (3 days) 2 days following hypophysectomy increased significantly 5α-reductase activity in whole testis. Large doses of testosterone propionate, however, did not appear to increase the activity above the level of the untreated hypophy-sectomized control, indicating that this effect of gonadotropins is not mediated through androgens. These studies clearly demonstrated that neither the immature nor the mature human testis possesses a high level of 5α-reductase activity as compared with the rat testis, and that 5oc-reductase activity in the rat testis is dependent on gonadotropic stimulation, in contrast to the androgen-dependent 5α-reductase in other target tissues.
Electron Bombardment of Silicon

The electrical properties of single crystal silicon have been investigated as a function of bombardment with high-energy electrons. Measurements of the initial carrier removal rate were carried out at 273\ifmmode^\circ\else\textdegree\fi{}K for samples with widely different carrier concentrations. A second type of experiment involved the measurement of the temperature dependence of resistivity and Hall coefficient at different stages of the bombardment. Bombardment-produced energy levels were found at 0.03 ev, 0.17 ev, and 0.4 ev below the edge of the conduction band. With 4.5-Mev electrons, the introduction rates for these levels were 11 ${\mathrm{cm}}^{\ensuremath{-}1}$, 0.5 ${\mathrm{cm}}^{\ensuremath{-}1}$, and 0.05 ${\mathrm{cm}}^{\ensuremath{-}1}$, respectively, Bombardment levels were also found at 0.05 ev and 0.3 ev above the edge of the valence band. With 4.5-Mev electrons the introduction rates for these levels were 13 ${\mathrm{cm}}^{\ensuremath{-}1}$ and roughly 0.3 ${\mathrm{cm}}^{\ensuremath{-}1}$, respectively. Irradiations with 700-kev electrons indicate the presence of the same defect levels with correspondingly smaller introduction rates. An investigation of the irradiation-induced mobility changes for degenerate $p$-type silicon indicates that, for each hole removed from the valence band, there appears a singly-charged scattering center. For near-degenerate $n$-type samples, the mobility changes are much smaller. Results of bombardments at 78\ifmmode^\circ\else\textdegree\fi{}K and 10\ifmmode^\circ\else\textdegree\fi{}K show that the net damage rate decreases by a factor of 2 or more when bombardments are carried out at lower temperatures.
An efficient method for representing and transmitting message patterns on multiprocessor interconnection networks

We describe a formalism for representing address sets, and for representing message patterns for multiprocessor interconnection networks. In this formalism a descriptor called a mask is used to represent a set of equal length bit vectors. Such a set can be interpreted as a set of processor addresses, or as a set of messages. We focus on the implications that this formalism has for routing message patterns on bundled omega networks. Specifically, we show that when a message pattern is represented in this formalism, a number of properties of the message pattern can be determined in polynomial time. This includes such things as determining whether the message pattern contains congestion. In addition, we show that the formalism defines a subclass of message patterns for which the minimum round partitioning problem, which in general is NP-hard, is solvable in linear time. We show this result to be true for both broadcast and non-broadcast bundled omega networks. This generalizes a known result for bit-permute-complement permutations to a more general class of message patterns, and to a larger class of networks.
A Convenient Synthesis of 2-(diethoxyphosphonyl)glycine and its derivatives

A simple and very efficient method for the preparation of 2-(diethoxyphosphonyl)-glycine and its N-methyl analog as the free acids is described and their conversion to the corresponding t-butyl esters demonstrated.
Corporate income tax competition, double taxation treaties, and foreign direct investment

Abstract In the presence of international capital mobility, foreign direct investment is influenced by corporate income tax rates and the rules of how taxes paid in the host country are treated at home. In this paper the exemption, credit and deduction methods are considered as tax rules. Tax competition is modeled as a non-cooperative game with respect to both corporate tax rates and the form of double taxation relief. The subgame perfect equilibrium is shown to be independent of the tax rules. Since capital is inefficiently allocated, the feasibility and the content of a cooperative contract between governments are analyzed. It is argued that only the credit method requires neither compensatory payments nor fully harmonized tax rates. This is consistent with the observation that tax credits are very often adopted in double taxation treaties.
Data Mining for Malicious Code Detection and Security Applications

Data mining is the process of posing queries and extracting patterns, often previously unknown from large quantities of data using pattern matching or other reasoning techniques. Data mining has many applications in security including for national security as well as for cyber security. The threats to national security include attacking buildings, destroying critical infrastructures such as power grids and telecommunication systems. Data mining techniques are being investigated to find out who the suspicious people are and who is capable of carrying out terrorist activities. Cyber security is involved with protecting the computer and network systems against corruption due to Trojan horses, worms and viruses. Data mining is also being applied to provide solutions such as intrusion detection and auditing.
Three‐dimensional magnetospheric equilibrium with isotropic pressure

In the absence of the toroidal flux, two coupled quasi two-dimensional elliptic equilibrium equations have been derived to describe self-consistent three-dimensional static magnetospheric equilibria with isotropic pressure in an optimal ({Psi},{alpha},{chi}) flux coordinate system, where {Psi} is the magnetic flux function, {chi} is a generalized poloidal angle, {alpha} is the toroidal angle, {alpha} = {phi} {minus} {delta}({Psi},{phi},{chi}) is the toroidal angle, {delta}({Psi},{phi},{chi}) is periodic in {phi}, and the magnetic field is represented as {rvec B} = {del}{Psi} {times} {del}{alpha}. A three-dimensional magnetospheric equilibrium code, the MAG-3D code, has been developed by employing an iterative metric method. The main difference between the three-dimensional and the two-dimensional axisymmetric solutions is that the field-aligned current and the toroidal magnetic field are finite for the three-dimensional case, but vanish for the two-dimensional axisymmetric case. With the same boundary flux surface shape, the two-dimensional axisymmetric results are similar to the three-dimensional magnetosphere at each local time cross section.
Bacteria Subsisting on Antibiotics

Antibiotics are a crucial line of defense against bacterial infections. Nevertheless, several antibiotics are natural products of microorganisms that have as yet poorly appreciated ecological roles in the wider environment. We isolated hundreds of soil bacteria with the capacity to grow on antibiotics as a sole carbon source. Of 18 antibiotics tested, representing eight major classes of natural and synthetic origin, 13 to 17 supported the growth of clonal bacteria from each of 11 diverse soils. Bacteria subsisting on antibiotics are surprisingly phylogenetically diverse, and many are closely related to human pathogens. Furthermore, each antibiotic-consuming isolate was resistant to multiple antibiotics at clinically relevant concentrations. This phenomenon suggests that this unappreciated reservoir of antibiotic-resistance determinants can contribute to the increasing levels of multiple antibiotic resistance in pathogenic bacteria.
The length of ionized meteor trails

The length of meteor ionization columns is defined as the maximum possible separation of points along the trail from which normal-incidence radio reflections may be obtained, when a radio system of prescribed characteristics is used. A statistical method is employed to determine the relative frequency of trails of different lengths from simultaneous measurements made at two similar 23-megacycle meteor detection stations 100 km apart. For sixth magnitude meteors, a mean trail length of 25 or 30 km is obtained.
Asymmetric Synthesis of anti-β-Amino-α-Hydroxy Esters via Dynamic Kinetic Resolution of β-Amino-α-Keto Esters

A method for the asymmetric synthesis of enantioenriched anti-α-hydroxy-β-amino acid derivatives by enantioconvergent reduction of the corresponding racemic α-keto esters is presented. The requisite α-keto esters are prepared via Mannich addition of ethyl diazoacetate to imines followed by oxidation of the diazo group with Oxone. Implementation of a recently developed dynamic kinetic resolution of β-substituted-α-keto esters via Ru(II)-catalyzed asymmetric transfer hydrogenation provides the title motif in routinely high diastereo- and enantioselectivity.
R&D Cuts and Subsequent Reversals: Meeting or Beating Quarterly Analyst Forecasts

AbstractAmong firms that meet or beat earnings expectations, we find that cuts to R&D spending are more prevalent in Q4 relative to other interim quarters. This is consistent with the relative costs of real-activities management (accruals-based earnings management) decreasing (increasing) in Q4 due to the annual audit. More importantly, we find that the subsequent reversal of such R&D cuts is more prevalent and economically more significant following Q4 cuts relative to the reversals that follow cuts in other interim quarters. Our findings suggest that examination at the quarterly level (rather than annual level) lends new insights into the current debate regarding the prevalence of potentially value-destroying R&D cuts that managers make. Indeed, our findings suggest that some cuts may merely be temporary deferrals of R&D outlays.
Studies for the synthesis of xenicane diterpenes. A stereocontrolled total synthesis of 4-hydroxydictyolactone.

The stereocontrolled total synthesis of 4-hydroxydictyolactone (4), a member of the xenicane diterpene family of natural products, is described. These studies feature the development of the B-alkyl Suzuki cross-coupling reaction for direct access to (E)-cyclononenes from acyclic precursors. The Ireland−Claisen rearrangement is effectively utilized to establish the backbone asymmetry of the contiguous C2, C3, C10 stereotriad of 4. The synthesis strategy has devised an intramolecular Nozaki−Hiyama reductive allylation of a formate ester for the stereoselective formation of five-membered lactols 22. In addition, an internally directed SE′ propargylation using allenylmagnesium bromide is described to establish the stereochemistry of the C4 alcohol in 27, and the terminal alkyne is subsequently functionalized via a regioselective syn-silylstannylation to yield 30. Finally, the stereocontrolled phenylselenylation of the ester enolate derived from 43 leads to the desired syn-oxidative elimination to yield the na...
THE STAR FORMATION LAW IN ATOMIC AND MOLECULAR GAS

We propose a simple theoretical model for star formation in which the local star formation rate (SFR) in a galaxy is determined by three factors. First, the interplay between the interstellar radiation field and molecular self-shielding determines what fraction of the gas is in molecular form and thus eligible to form stars. Second, internal feedback determines the properties of the molecular clouds that form, which are nearly independent of galaxy properties until the galactic interstellar medium (ISM) pressure becomes comparable to the internal giant molecular cloud (GMC) pressure. Above this limit, galactic ISM pressure determines molecular gas properties. Third, the turbulence driven by feedback processes in GMCs makes star formation slow, allowing a small fraction of the gas to be converted to stars per free-fall time within the molecular clouds. We combine analytic estimates for each of these steps to formulate a single star formation law, and show that the predicted correlation between SFR, metallicity, and surface densities of atomic, molecular, and total gas agree well with observations.
Topological electromotive force from domain-wall dynamics in a ferromagnet

We formulate a local gauge-invariant theory for the electromotive force induced by domain-wall dynamics in a ferromagnet. We demonstrate that this emf generation is a real-space topological pumping effect. The integral of the emf over one pumping period is a quantized topological invariant which does not depend on the details of the domain-wall configuration nor on its detailed dynamics. Based on our theory, the full instantaneous electric potential distribution can be mapped out by standard electrostatic methods. We also provide further details on our recent experiments which confirmed the emf induced by domain-wall dynamics.
The phase diagram of QCD

Abstract We show that current experimental knowledge of QCD together with general model independent arguments such as continuity, universality and thermodynamic relations, as well as the information gained from various models can be used to constrain the phase diagram of QCD as a function of temperature and baryon chemical potential.
Comparison of bursting pressure of sutured, stapled and BAR anastomoses

The study was undertaken to compare anastomotic bursting pressure (ABP) of colorectal canine anastomoses using three different anastomotic techniques. Biofragmentable anastomotic ring (BAR), stapled, and sutured colon anastomoses were sequentially placed in each of 48 dogs following division of the colon at three equally spaced sites. Four groups of 12 dogs were sacritficed either on day 0, 3, 7, or 28 and ABP and bursting wall tension were determined. The data revealed that BAR anastomoses have the greatest strength on the day of surgery, sutured anastomoses are the strongest on the third day and all are comparable by the 7th day. Bursting pressures for all groups by day 28 approach normal colonic bursting pressure, with any differences likely to be a reflection of variation in anastomotic fibrosis and other factors.
High-Fat Diet Triggers Inflammation-Induced Cleavage of SIRT1 in Adipose Tissue To Promote Metabolic Dysfunction

Adipose tissue plays an important role in storing excess nutrients and preventing ectopic lipid accumulation in other organs. Obesity leads to excess lipid storage in adipocytes, resulting in the generation of stress signals and the derangement of metabolic functions. SIRT1 is an important regulatory sensor of nutrient availability in many metabolic tissues. Here we report that SIRT1 functions in adipose tissue to protect from inflammation and obesity under normal feeding conditions, and to forestall the progression to metabolic dysfunction under dietary stress and aging. Genetic ablation of SIRT1 in adipose tissue leads to gene expression changes that highly overlap with changes induced by high-fat diet in wild-type mice, suggesting that dietary stress signals inhibit the activity of SIRT1. Indeed, we show that high-fat diet induces the cleavage of SIRT1 protein in adipose tissue by the inflammation-activated caspase-1, providing a link between dietary stress and predisposition to metabolic dysfunction.
A four-faceted knowledge-based approach for surmounting borders

While the evolving high bandwidth information highways provide the infrastructure for attaining “physical connectivity” across computing resources and information systems, the “on/off” ramps to such highways are still at a primitive stage. Huge manual effort is currently expended to develop knowledge‐based paradigms that can effectively transcend national borders as well as other types of borders. This paper examines the prevailing situation from four perspectives: knowledge acquisition; knowledge discovery; knowledge management; and knowledge dissemination. Unlike current approaches that tend to focus on one aspect only, an integrated approach that attaches appropriate weightage to each of the four facets is emphasized in this paper.
Ancient aqueous sedimentation on Mars

Viking orbiter images are presently used to calculate approximate volumes for the inflow valleys of the ancient cratered terrain of Mars; a sediment-transport model is then used to conservatively estimate the amount of water required for the removal of this volume of debris from the valleys. The results obtained for four basins with well-developed inflow networks indicate basin sediment thicknesses of the order of tens to hundreds of meters. The calculations further suggest that the quantity of water required to transport the sediment is greater than that which could be produced by a single discharge of the associated aquifer, unless the material of the Martian highlands was very fine-grained and noncohesive to depths of hundreds of meters.
The triad in crisis: What we learned and how it will change global cooperation

Abstract This paper reviews the propagation of the 2008–2009 financial crisis through China, Japan and the United States (the “triad”) and analyzes the responses of these countries from the viewpoints of achieving recovery and returning to a growth path that will be free of the imbalances that limit long-term sustainability. For a variety of reasons, the triad countries are both key protagonists in the crisis, and central agents in the recovery from it. Greater cooperation among them will be important to ensure that the recovery that emerges leads to a sustainable growth path. Their actions are important also because they can have great influence on the responses of other countries. The paper concludes with an overview of areas in which cooperation is especially desirable.
SYM description of PP-wave string interactions: singlet sector and arbitrary impurities

Abstract We study string interactions among string states with arbitrary impurities in the type IIB plane wave background using string field theory. We reproduce all string amplitudes from gauge theory by computing matrix elements of the dilatation operator in a previously proposed basis of states. A direct correspondence is found between the string field theory and gauge theory Feynman diagrams.
Spectral collocation methods

This review covers the theory and application of spectral collocation methods. Section 1 describes the fundamentals, and summarizes results pertaining to spectral approximations of functions. Some stability and convergence results are presented for simple elliptic, parabolic, and hyperbolic equations. Applications of these methods to fluid dynamics problems are discussed in Section 2.
Diastereoselective intramolecular pinacol couplings of sulfinyl iron(0) diene complexes.

3-(2-Formylaryl)-1-sulfinyl-(1Z,3E)-pentadien-5-al iron tricarbonyl complexes were prepared to examine the feasibility and diastereoselectivity of intramolecular pinacol couplings on such substrate...
Fatigue reliability of gas turbine engine components under scheduledinspection maintenance

A probabilistic method is developed for the fatigue reliability analysis of gas turbine engine components under scheduled inspection maintenance in service. Various statistical uncertainties involved in the complex design system of gas turbine engine components have been taken into account, including the time to crack initiation, fatigue crack propagation, service loads, crack modeling, stress concentration factor, nondestructive evaluation (NDE) etc. It is demonstrated that the service inspection maintenance can be used to improve the reliability of fatigue-critical components significantly. Such an improvement in fatigue reliability is shown to depend on the capability of the NDE system employed. An example for the third stage turbine disk of TF33 jet engine has been worked out to demonstrate the application of the analysis methodology developed herein.
Higgs and dark matter hints of an oasis in the desert

Recent LHC results suggest a standard model (SM)-like Higgs boson in the vicinity of 125 GeV with no clear indications yet of physics beyond the SM. At the same time, the SM is incomplete, since additional dynamics are required to accommodate cosmological dark matter (DM). In this paper we show that interactions between weak scale DM and the Higgs which are strong enough to yield a thermal relic abundance consistent with observation can easily destabilize the electroweak vacuum or drive the theory into a non-perturbative regime at a low scale. As a consequence, new physics — beyond the DM itself — must enter at a cutoff well below the Planck scale and in some cases as low as O(10-1000 TeV), a range relevant to indirect probes of flavor and CP violation. In addition, this cutoff is correlated with the DM mass and scattering cross-section in a parameter space which will be probed experimentally in the near term. Specifically, we consider the SM plus additional spin 0 or 1/2 states with singlet, triplet, or doublet electroweak quantum numbers and quartic or Yukawa couplings to the Higgs boson. We derive explicit expressions for the full two-loop RGEs and one-loop threshold corrections for these theories.
Reserve prices in a dynamic auction when bidders are capacity-constrained

Abstract Allowing for a reserve price in a dynamic auction with capacity-constrained bidders changes the equilibrium in an unexpected way. The distribution of winning bids contains a mass point; several bidder types “bunch” at the reserve price.
Perturbative corrections to a sum rule for the heavy quark kinetic energy

Abstract We calculate the perturbative corrections to order α s 2 β 0 to the sum rule derived from the second moment of the time-ordered product of b → c currents near zero recoil. This sum rule yields a bound on λ 1 , the expectation value of the b quark kinetic energy operator inside the B meson. The perturbative corrections significantly weaken the bound relative to the tree level result, yielding λ 1 2 .
Cosmological Structure Formation Creates Large-Scale Magnetic Fields

This paper examines the generation of seed magnetic fields due to the growth of cosmological perturbations. In the radiation era, different rates of scattering from photons induce local differences in the ion and electron density and velocity fields. The currents due to the relative motion of these fluids generate magnetic fields on all cosmological scales, peaking at a magnitude of O(10-24 G) at the epoch of recombination. Magnetic fields generated in this manner provide a promising candidate for the seeds of magnetic fields currently observed on galactic and extragalactic scales.
Controlled sensing: A myopic fisher information sensor selection algorithm

This paper considers the problem of state tracking with observation control for a particular class of dynamical systems. The system state evolution is described by a discrete-time, finite-state Markov chain, while the measurement process is characterized by a controlled multi-variate Gaussian observation model. The computational complexity of the optimal control strategy proposed in our prior work proves to be prohibitive. A suboptimal, lower complexity algorithm based on the Fisher information measure is proposed. Toward this end, the preceding measure is generalized to account for multi-valued discrete parameters and control inputs. A closed-form formula for our system model is also derived. Numerical simulations are provided for a physical activity tracking application showing the near-optimal performance of the proposed algorithm.
DC distribution for industrial systems: opportunities and challenges

This paper investigates the opportunities and challenges associated with adopting a DC distribution scheme for industrial power systems. A prototype DC distribution system has been simulated to investigate the issues. One of the issues focused is the interaction between power converters that are used to convert AC to DC and DC to AC. Another challenging issue investigated is the system grounding. These issues become challenging mainly due to the neutral voltage shift associated with the power converters. The paper shows that converter interactions can be minimized with proper filtering and control on the converters. The paper also proposes a grounding scheme and shows that this scheme provides an effective solution by keeping the neutral voltages low under normal conditions and by limiting the fault currents during fault conditions. With these features, DC distribution provides very reliable and high-quality power.
The Jastrow antisymmetric geminal power in Hilbert space: Theory, benchmarking, and application to a novel transition state

The Jastrow-modified antisymmetric geminal power (JAGP) ansatz in Hilbert space successfully overcomes two key failings of other pairing theories, namely, a lack of inter-pair correlations and a lack of multiple resonance structures, while maintaining a polynomially scaling cost, variational energies, and size consistency. Here, we present efficient quantum Monte Carlo algorithms that evaluate and optimize the JAGP energy for a cost that scales as the fifth power of the system size. We demonstrate the JAGP’s ability to describe both static and dynamic correlation by applying it to bond stretching in H2O, C2, and N2 as well as to a novel, multi-reference transition state of ethene. JAGP’s accuracy in these systems outperforms even the most sophisticated single-reference methods and approaches that of exponentially scaling active space methods.
Psychosocial Variables Associated with the Exceptional Survival of Patients with Advanced Malignant Disease

This study identified psychosocial variables associated with the exceptional survival of nine cancer patients diagnosed terminal. During open-ended interviews, subjects described their behaviors and emotions following disease onset, and articulated personal explanations for the unusually positive results attained. Despite the methodological limitations inherent in this type of research, the similarity of subjects' responses was compelling. All subjects believed that there was a direct relationship between the outcomes experienced and their psychological states. They remained confident that they would not die, and assert that these positive expectations were critical to the healing process. The report by subjects that they experienced major psychosocial changes in the months following their prognoses presents a serious challenge to the conclusions of a related study by Cassileth et al. [1]. The subjects assumed responsibility for all aspects of their lives, including recovery. Thus, medical personnel were ...
Representation Type Preferences in Operational Business Process Redesign: A Quasi-Experimental Field Investigation

This paper reports on a quasi-experimental field study in which business process redesign groups in four different US organizations used two different business process representation types. One of the representation types emphasized an activity flow or workflow view of business processes, which appears to currently be the most prevalent in actual operational-level business process redesign projects; the other emphasized a communication flow view. The study suggests that, contrary to assumptions likely underlying most of the current business process redesign practice, communication flow-oriented representations of business processes are perceived by those involved in their redesign as significantly more useful in the following aspects than activity flow-oriented representations: identification of opportunities for process improvement, application of process redesign guidelines, visualization of process changes, and development of generic information technology solutions to implement new business processes. Important implications for managers and researchers stemming from these results are discussed.
How many random edges make a dense hypergraph non-2-colorable?

We study a model of random uniform hypergraphs, where a random instance is obtained by adding random edges to a large hypergraph of a given density. The research on this model for graphs has been started by Bohman et al. (Random Struct Algorithms 22 (2003) 33–42), and continued in (Bohman et al., Random Struct Algorithms 24 (2004) 105–117) and (Krivelevich et al., Random Struct Algorithms 29 (2006), 180–193). Here we obtain a tight bound on the number of random edges required to ensure non-2-colorability. We prove that for any k-uniform hypergraph with Ω(nk-e) edges, adding ω(nke-2) random edges makes the hypergraph almost surely non-2-colorable. This is essentially tight, since there is a 2-colorable hypergraph with Ω(nk-e) edges which almost surely remains 2-colorable even after adding o(nke-2) random edges.© 2007 Wiley Periodicals, Inc. Random Struct. Alg., 2008
Sulfided group VIII metals for hydroformylation

Abstract Nickel sulfide and sulfided group VIII metals including nickel, cobalt, iron, ruthenium, iridium and osmium have been found to exhibit hydroformylation activities at 150–300°C and 10 atm.
Impressive structural diversity and polymorphism in the modular compounds ABi3Q5 (A = Rb, Cs; Q = S, Se, Te).

An outstanding example of structural diversity and complexity is found in the compounds with the general formula ABi3Q5 (A = alkali metal; Q = chalcogen). γ-RbBi3S5 (I), α-RbBi3Se5 (II), β-RbBi3Se5 (III), γ-RbBi3Se5 (IV), CsBi3Se5 (V), RbBi3Se4Te (VI), and RbBi3Se3Te2 (VII) were synthesized from A2Q (A = Rb, Cs; Q = S, Se) and Bi2Q3 (Q = S, Se or Te) at temperatures above 650 °C using appropriate reaction protocols. γ-RbBi3S5 and α-RbBi3Se5 have three-dimensional tunnel structures while the rest of the compounds have lamellar structures. γ-RbBi3S5, γ-RbBi3Se5, and its isostructural analogues RbBi3Se4Te and RbBi3Se3Te2 crystallize in the orthorhombic space group Pnma with a = 11.744(2) A, b = 4.0519(5) A, c = 21.081(3) A, R1 = 2.9%, wR2 = 6.3% for (I), a = 21.956(7) A, b = 4.136(2) A, c = 12.357(4) A, R1 = 6.2%, wR2 = 13.5% for (IV), and a = 22.018(3) A, b = 4.2217(6) A, c = 12.614(2) A, R1 = 6.2%, wR2 = 10.3% for (VI). γ-RbBi3S5 has a three-dimensional tunnel structure that differs from the Se analogues. ...
Building a standards-based and collaborative e-prescribing tool: MyRxPad

MyRxPad (rxp.nlm.nih.gov) is a prototype application intended to enable a practitioner patient collaborative approach towards e-prescribing: patients play an active role by maintaining up-to-date and accurate medication lists. Prescribers make well-informed and safe prescribing decisions based on personal medication records contributed by patients. MyRxPad is thus the vehicle for collaborations with patients using MyMedicationList (MML). Integration with personal medication records in the context of e-prescribing is thus enabled. We present our experience in applying RxNorm in an e-prescribing setting: using standard names and codes to capture prescribed medication as well as extracting information from RxNorm to support medication-related clinical decision.
Simulation of Reduction of Cr(VI) by Fe(II) Produced Electrochemically in a Parallel-Plate Electrochemical Reactor

A model is presented for the reduction of hexavalent chromium in a parallel-plate electrochemical reactor via a homogenous reaction between Cr(VI) and Fe(II) generated at the iron anode. The effects of the space velocity of the feed solution, the concentration of supporting electrolyte, the distance between the electrodes, and the cell potential on conversion of Cr(VI) to Cr(III), are discussed. This study indicates that for reduction of Cr(VI) using Fe(II), the space velocity must be maintained below 0.02 s -1 or the system becomes limited by the rate of reduction of Cr(VI) by Fe(II). Increasing the current density by increasing the cell potential, increasing the amount of supporting electrolyte, and decreasing the distance between the electrodes increases single pass conversion of Cr(VI) to Cr(III); however, increasing the current density also increases the specific energy required by the system.
Numerical Approximation of the Singularly Perturbed Heat Equation in a Circle

In this article we study the two dimensional singularly perturbed heat equation in a circular domain. The aim is to develop a numerical method with a uniform mesh, avoiding mesh refinement at the boundary thanks to the use of a relatively simple representation of the boundary layer. We provide the asymptotic expansion of the solution at first order and derive the boundary layer element resulting from the boundary layer analysis. We then perform the convergence analysis introducing the boundary layer element in the finite element space thus obtaining what is called an "enriched Galerkin space". Finally we present and comment on numerical simulations using a quasi-uniform grid and the modified finite element method.
Relativistic Aharonov-Bohm-Coulomb Problem

The ((2+1)-dimensional) Aharonov{endash}Bohm effect is analyzed for a spin-1/2 particle in the case that a 1/{ital r} potential is present. Scalar and vector couplings are each considered. It is found that the approach in which the flux tube is given a finite radius that is taken to zero only after a matching of boundary conditions does not give physically meaningful results. Specifically, the operations of taking the limit of zero flux tube radius and the Galilean limit do not commute. Thus there appears to be no satisfactory solution of the relativistic Aharonov{endash}Bohm{endash}Coulomb problem using the finite radius flux tube method. Copyright {copyright} 1996 Academic Press, Inc.
Increasing tree search efficiency for constraint satisfaction problems

Abstract In this paper we explore the number of tree search operations required to solve binary constraint satisfaction problems. We show analytically and experimentally that the two principles of first trying the places most likely to fail and remembering what has been done to avoid repeating the same mistake twice improve the standard backtracking search. We experimentally show that a lookahead procedure called forward checking (to anticipate the future) which employs the most likely to fail principle performs better than standard backtracking, Ullman's, Waltz's, Mackworth's, and Haralick's discrete relaxation in all cases tested, and better than Gaschnig's backmarking in the larger problems.
How Sample Completeness Affects Gamma-Ray Burst Classification

Unsupervised pattern-recognition algorithms support the existence of three gamma-ray burst classes: class 1 (long, large-fluence bursts of intermediate spectral hardness), class 2 (short, small-fluence, hard bursts), and class 3 (soft bursts of intermediate durations and fluences). The algorithms surprisingly assign larger membership to class 3 than to either of the other two classes. A known systematic bias has been previously used to explain the existence of class 3 in terms of class 1 ; this bias allows the fluences and durations of some bursts to be underestimated, as recently shown by Hakkila et al. We show that this bias primarily affects only the longest bursts and cannot explain the bulk of the class 3 properties. We resolve the question of class 3's existence by demonstrating how samples obtained using standard trigger mechanisms fail to preserve the duration characteristics of small-peak flux bursts. Sample incompleteness is thus primarily responsible for the existence of class 3. In order to avoid this incompleteness, we show how a new, dual-timescale peak flux can be defined in terms of peak flux and fluence. The dual-timescale peak flux preserves the duration distribution of faint bursts and correlates better with spectral hardness (and presumably redshift) than either peak flux or fluence. The techniques presented here are generic and have applicability to the studies of other transient events. The results also indicate that pattern recognition algorithms are sensitive to sample completeness; this can influence the study of large astronomical databases, such as those found in a virtual observatory.
Face ring multiplicity via CM-connectivity sequences

The multiplicity conjecture of Herzog, Huneke, and Srinivasan is verified for the face rings of the following classes of simplicial complexes: matroid complexes, complexes of dimension one and two, and Gorenstein complexes of dimension at most four. The lower bound part of this conjec- ture is also established for the face rings of all doubly Cohen-Macaulay complexes whose 1-skeleton's connectivitydoes not exceed the codimension plusone as wellas forall(d −1)-dimensional d-Cohen- Macaulay complexes. The main ingredient of the proofs is a new interpretation of the minimal shifts in the resolution of the face ring k(�) via the Cohen-Macaulay connectivity of the skeletons of �.
An application of the Black–Litterman model with EGARCH-M-derived views for international portfolio management

This paper provides an application of the Black–Litterman methodology to portfolio management in a global setting. The novel feature of this paper relative to the extant literature on Black–Litterman methodology is that we use GARCH-derived views as an input into the Black–Litterman model. The returns on our portfolio surpass those of portfolios that rely on market equilibrium weights or Markowitz-optimal allocations. We thereby illustrate how the Black–Litterman model can be put to work in designing global investment strategies.
Control of automobile traffic: a problem in real-time computation

Automobile traffic in urban areas has been characterized as one of our most serious engineering problems. Fig. 1 to Fig. 3 show respectively for one particular area the recent increases in population, motor vehicle registrations, and motor vehicle registrations per person. Some urban areas have approached the traffic problem by the construction of a network of superhighways or freeways. In other areas a solution has been sought through improved traffic controls on existing streets. But in many cases traffic continues to grow more rapidly than corrective measures can be provided. The question is frequently asked, therefore, "Can we improve traffic movement by some control system which takes advantage of the abilities of the large-scale automatic computer?" It is the purpose of this paper to discuss some of the possibilities and difficulties involved.
EVIDENCE FOR LARGE TEMPERATURE FLUCTUATIONS IN QUASAR ACCRETION DISKS FROM SPECTRAL VARIABILITY

The well-known bluer-when-brighter trend observed in quasar variability is a signature of the complex processes in the accretion disk and can be a probe of the quasar variability mechanism. Using a sample of 604 variable quasars with repeat spectra in the Sloan Digital Sky Survey-I/II (SDSS), we construct difference spectra to investigate the physical causes of this bluer-when-brighter trend. The continuum of our composite difference spectrum is well fit by a power law, with a spectral index in excellent agreement with previous results. We measure the spectral variability relative to the underlying spectra of the quasars, which is independent of any extinction, and compare to model predictions. We show that our SDSS spectral variability results cannot be produced by global accretion rate fluctuations in a thin disk alone. However, we find that a simple model of an inhomogeneous disk with localized temperature fluctuations will produce power-law spectral variability over optical wavelengths. We show that the inhomogeneous disk will provide good fits to our observed spectral variability if the disk has large temperature fluctuations in many independently varying zones, in excellent agreement with independent constraints from quasar microlensing disk sizes, their strong UV spectral continuum, and single-band variability amplitudes. Our results provide an independent constraint on quasar variability models and add to the mounting evidence that quasar accretion disks have large localized temperature fluctuations.