cssi/SciSciGPT-SciSciNet huggingface dataset:
Representations of affine Lie algebras, elliptic r-matrix systems, and special functions

The author considers an elliptic analogue of the Knizhnik-Zamolodchikov equations—the consistent system of linear differential equations arising from the elliptic solution of the classical Yang-Baxter equation for the Lie algebra\(\mathfrak{s}\mathfrak{l}_N \). The solutions of this system are interpreted as traces of products of intertwining operators between certain representations of the affine Lie algebra Open image in new window . A new differential equation for such traces characterizing their behavior under the variation of the modulus of the underlying elliptic curve is deduced. This equation is consistent with the original system.
Phase behavior in the Li-Al-O-H system at intermediate temperatures

It has been demonstrated that a material of initial composition Li5AlO4 will, in a wet environment, support continuous direct current in the presence of Pt electrodes at intermediate temperatures. This has been attributed to the conduction of hydroxide ions derived from the formation of LiOH. The observed behavior in this system is discussed with reference to the calculated Li-Al-O-H phase diagram.
D-terms, unification, and the Higgs mass

We study gauge extensions of the MSSM that contain non-decoupling D-terms, which contribute to the Higgs boson mass. These models naturally maintain gauge coupling unification and raise the Higgs mass without fine-tuning. Unification constrains the structure of the gauge extensions, limiting the Higgs mass in these models to mh 150 GeV. The D-terms contribute to the Higgs mass only if the extended gauge symmetry is broken at energies of a few TeV, leading to new heavy gauge bosons in this mass range.
Noncommutative sets of small doubling

One sees that, as a corollary of Kneser's theorem, any finite non-empty subset A of an abelian group G = ( G , + ) with | A + A | ? ( 2 - e ) | A | can be covered by at most 2 e - 1 translates of a finite group H of cardinality at most ( 2 - e ) | A | . Using some arguments of Hamidoune, we establish an analogue in the noncommutative setting. Namely, if A is a finite non-empty subset of a nonabelian group G = ( G , ? ) such that | A ? A | ? ( 2 - e ) | A | , then A is either contained in a right-coset of a finite group H of cardinality at most 2 e | A | , or can be covered by at most 2 e - 1 right-cosets of a finite group H of cardinality at most | A | . We also note some connections with some recent work of Sanders and of Petridis.
Advanced Computer Technology for Novel Information Processing Paradigms

Advanced computer technologies for novel information processing paradigms to be applied to command and control systems of the next decades are presented in this paper. The Advanced Computing Technology Branch (IFTC) within the Air Force Research Laboratory’s (AFRL) Information Directorate is exploring and developing many technological avenues to incorporate novel information processing capabilities that address future command and control (C2) systems requirements. The research and development process includes but is not limited to participation in Defense Advanced Research Projects Agency (DARPA) research programs, and utilization of United States Air Force funded research and development activity especially in-house research programs. The authors provide a snapshot of computer technologies that the military aerospace community will see in future information systems. These systems include near term technologies composed of hybrid hardware/software computing architectures incorporating Processor In Memory (PIM) into conventional computers, architectures that are capable of dynamically morphing their hardware and software when required, and high productivity computing systems. Far term systems will include biomolecular and quantum computing architectures that incorporate data storage and processing mechanisms with density, power, and speed performances far beyond state-of-the-art silicon technologies. Pursuit of the technologies presented in this paper permits researchers to explore computer architectures with greater capacity and sophistication for addressing dynamic mission objectives under constraints imposed by Command, Control, Communication and Computer (C4), Intelligence, Surveillance and Reconnaissance (ISR), and strike systems in order to establish, maintain, and exploit information superiority.
Comparative planetary mineralogy: Valence state partitioning of Cr, Fe, Ti, and V among crystallographic sites in olivine, pyroxene, and spinel from planetary basalts

This is a comparative planetary mineralogy study emphasizing the valence-state partitioning of Cr, Fe, Ti, and V over crystallographic sites in olivine, pyroxene, and spinel from planetary basalts. The sites that accommodate these cations are the M2 site (6 to 8-coordinated) and M1 site (6-coordinated) in pyroxene, the M2 site (6- to 8-coordinated) and Ml (6-coordinated site) in olivine, and the tetrahedral and octahedral sites in spinel. The samples we studied are basalts from Earth, Moon, and Mars, and range in oxygen fugacity conditions from IW-2 (Moon) to IW+6 (Earth), with Mars somewhere in between (IW to IW+2). The significant elemental valence-states at these f o 2 conditions are (from low to high f o 2 ): Ti 4 + , V 3 + , Fe 2 + , Cr 2 + , Cr 3 + , V 4 + , and Fe 3 + . V 2 + and Ti 3 + play a minor role in the phases considered for the Moon, and are found in very low concentrations. V 5 + plays a minor role in these phases in oxidized terrestrial basalts because it is probably lower in abundance than V 4 + , and has an ionic radius that is so small (0.054 nm, 6-coordinated), that it is almost at the lower limit for octahedral coordination, and can even be tetrahedrally coordinated. The role of Cr 2 + in the Moon is significant, as Cr 2 + predominates in basaltic melts at f o 2 less than IW-1. Lunar olivine has been found to contain mostly Cr 2 + , whereas coexisting pyroxene contains mostly Cr 3 + . Fe 3 + is very important in Earth, less so in Mars, and nonexistent in the Moon. The importance of the Fe 2 + to Fe 3 + transition cannot be overstated and, indeed, their crystal-chemical differences, in terms of behavior (based on size and charge), are similar to the differences between Mg and Al. We note that for pyroxene in six of the seven terrestrial suites we studied, Fe 3 + (in the M1 site) coupled with Al (in the tetrahedral site) is one of the two most important charge-balance substitutions. This substitution is of lesser importance in Mars and does not exist in lunar basalts.
Bar-driven Dark Halo Evolution: A Resolution of the Cusp-Core Controversy

Simulations predict that the dark matter halos of galaxies should have central cusps, while those inferred from observed galaxies do not have cusps. We demonstrate, using both linear perturbation theory and n-body simulations, that a disk bar, which should be ubiquitous in forming galaxies, can produce cores in cuspy CDM dark matter profiles within five bar orbital times. Simulations of forming galaxies suggest that one of Milky Way size could have a 10 kpc primordial bar; this bar will remove the cusp out to �5 kpc in �1.5 gigayears, while the disk only loses �8% of its original angular momentum. An inner Lindblad-like resonance couples the rotating bar to orbits at all radii through the cusp, transferring the bar pattern angular momentum to the dark matter cusp, rapidly flattening it. This resonance disappears for profiles with cores and is responsible for a qualitative difference in bar driven halo evolution with and without a cusp. This bar induced evolution will have a profound effect on the structure and evolution of almost all galaxies. Hence, both to understand galaxy formation and evolution and to make predictions from theory it is necessary to resolve these dynamical processes. Unfortunately, correctly resolving these important dynamical processes in ab initio calculations of galaxy formation is a daunting task, requiring at least 4,000,000 halo particles using our SCF code, and probably requiring many times more particles when using noisier tree, direct summation, or grid based techniques, the usual methods employed in such calculations. Subject headings: galaxies:evolution — galaxies: halos — galaxies: kinematics and dynamics — cosmology: theory — dark matter
Rank-determining sets of metric graphs

A metric graph is a geometric realization of a finite graph by identifying each edge with a real interval. A divisor on a metric graph @C is an element of the free abelian group on @C. The rank of a divisor on a metric graph is a concept appearing in the Riemann-Roch theorem for metric graphs (or tropical curves) due to Gathmann and Kerber, and Mikhalkin and Zharkov. We define a rank-determining set of a metric graph @C to be a subset A of @C such that the rank of a divisor D on @C is always equal to the rank of D restricted on A. We show constructively in this paper that there exist finite rank-determining sets. In addition, we investigate the properties of rank-determining sets in general and formulate a criterion for rank-determining sets. Our analysis is based on an algorithm to derive the v"0-reduced divisor from any effective divisor in the same linear system.
Stereocontrolled Preparation of Spirocyclic Ethers by Intramolecular Trapping of Oxonium Ions with Allylsilanes.

The stereoselectivity of the spontaneous intramolecular cyclization of 2-(benzenesulfonyl)-2-(4-((trimethylsilyl)methyl)-4-pentenyl)tetrahydropyrans substituted by alkyl groups at various ring positions has been examined. For the 4- and 6-methyl derivatives, formation of the spirocyclic center occurs exclusively anti to the methyl. The outcome in the 5-methyl example is a 3.7:1 syn/anti split. For the trans-4,6-dimethyl derivative, the substituents act in a reinforcing manner and direct cyclization uniquely in one direction. Both the cis and trans bicyclic ethers ring close on that π-surface of the intermediate oxonium ion syn to the angular hydrogen. The results are rationalized in terms of the predilection of the associated oxonium ions for nucleophilic capture via a chairlike or twist-boat transition state.
Boundary terms in the action principles of general relativity

I address the question: “What is fixed on the boundary in the action principles of general relativity?” Four forms of the action are considered: the Einstein action, the Hilbert action, the first order action, and what may be called the cosmological action. The relationships and boundary data of these actions are described geometrically. Formal passage to the “Euclidean” forms of these actions is effected in detail.
Low distortion spanners

A spanner of an undirected unweighted graph is a subgraph that approximates the distance metric of the original graph with some specified accuracy. Specifically, we say H ⊆ G is an f-spanner of G if any two vertices u,v at distance d in G are at distance at most f(d) in H. There is clearly some trade-off between the sparsity of H and the distortion function f, though the nature of the optimal trade-off is still poorly understood.In this article we present a simple, modular framework for constructing sparse spanners that is based on interchangable components called connection schemes. By assembling connection schemes in different ways we can recreate the additive 2- and 6-spanners of Aingworth et al. [1999] and Baswana et al. [2009], and give spanners whose multiplicative distortion quickly tends toward 1. Our results rival the simplicity of all previous algorithms and provide substantial improvements (up to a doubly exponential reduction in edge density) over the comparable spanners of Elkin and Peleg [2004] and Thorup and Zwick [2006].
Introductory remarks: Regional economy and families of neuroregulatory substances

Publisher Summary This chapter describes the regional economy and families of neuroregulatory substances. The neurons of reticular activating system bear a somewhat special and reciprocal relation to the afferent pathways which impinge upon them by way of collaterals. They are activated by these, but equally, through their activity determine the ultimate perception of the signal arriving at the cortex by way of the sense-linked pathways. The translation of afferent signals into perception may well depend on the interaction of cortical and reticular elements. Also it may have its neural counterpart in the three-dimensional apposition, and patterning of excitory and inhibitory states in a very large cell population. The reticular formation is distinctive for the diffuseness of their connections, and of their effects. Equally, in this dense reticular field self-excitory phenomena may predominate, and the powerful operation of vectorial and spatial influences is likely. The reticular formation is distinctive for the diffuseness of their connections, and of their effects. Equally, in this dense reticular field self-excitory phenomena may predominate, and the powerful operation of vectorial and spatial influences is likely.
Terminal Navigation Analysis for the 1980 Comet Encke Slow Flyby Mission

The initial results of a terminal navigation analysis for the proposed 1980 solar electric slow flyby mission to the comet Encke are presented. The navigation technique employs onboard optical measurements with the scientific television camera, groundbased observations of the spacecraft and comet, and groundbased orbit determination and thrust vector update computation. The knowledge and delivery accuracies of the spacecraft are evaluated as a function of the important parameters affecting the terminal navigation. These include optical measurement accuracy, thruster noise level, duration of the planned terminal coast period, comet ephemeris uncertainty, guidance initiation time, guidance update frequency, and optical data rate.
Firm Resources and Sustained Competitive Advantage

Understanding sources of sustained competitive advantage has become a major area of research in strategic management. Building on the assumptions that strategic resources are heterogeneously distributed across firms and that these differences are stable over time, this article examines the link between firm resources and sustained competitive advantage. Four empirical indicators of the potential of firm resources to generate sustained competitive advantage-value, rareness, imitability, and substitutability are discussed. The model is applied by analyzing the potential of several firm resources for generating sustained competitive advantages. The article concludes by examining implications of this firm resource model of sustained competitive advantage for other business disciplines.
Radar Observations of Asteroid 7822 (1991 CS)

Abstract We report Doppler-only (cw) radar observations of near-Earth asteroid 1991 CS obtained at Goldstone at a transmitter frequency of 8510 MHz (3.5 cm) on 1996 August 26, 27, 28, and 29. Weighted, optimally filtered sums of cw echoes achieve signal-to-noise ratios in excess of 300 per day and thoroughly cover the asteroid in rotation phase (synodic period=2.39 h, obtained photometrically by P. Pravec et al. 1998, Icarus 136 , 124–153). A weighted sum of all cw spectra gives an OC radar cross section of 0.24±0.08 km 2 and a circular polarization ratio of 0.28±0.001. Our observations place up to 50 0.98-Hz resolution cells on 1991 CS at echo powers greater than 2 standard deviations of the noise. Variations of ∼10 Hz in the echo's 2-σ bandwidth are evident on each day and are consistent with the rotation period. Inversion of echo edge frequencies yields convex hulls of the pole-on silhouette for each day. The hulls have a mean elongation and rms dispersion of 1.18±0.02 and place a lower bound on the maximum pole-on dimension of 1.3 km/cosδ, where δ is the angle between the radar line-of-sight and the asteroid's apparent equator. The hulls suggest that 1991 CS has the least elongated pole-on silhouette of any of the nine near-Earth asteroids for which similar shape information from radar observations is available. If we assume that the projected area of 1991 CS is the same as that of a sphere with a diameter of 1.1 km, equal to the lower bound on the minimum breadth of the pole-on silhouette on August 28 and 29, then 1991 CS's radar cross section and absolute magnitude of 17.5 correspond to upper limits on the radar and optical geometric albedos of 0.25 and 0.14 that are consistent with its S-class taxonomy. The circular polarization ratio and radar albedo do not vary substantially as a function of rotation phase, suggesting that the near-surface of 1991 CS is relatively uniform. Among the 20 S-class asteroid radar detections previously reported, the circular polarization ratio of 1991 CS is greater than 11, comparable to 4, and less than 5.
Intercalated clay nanocomposites: Morphology, mechanics, and fracture behavior

Intercalated nanocomposites of modified montmorillonite clays in a glassy epoxy were prepared by crosslinking with commercially available aliphatic diamine curing agents. These materials are shown to have improved Young's modulus but corresponding reductions in ultimate strength and strain to failure. The results were consistent with most particulate-filled systems. The macroscopic compressive behavior was unchanged, although the failure mechanisms in compression varied from the unmodified samples. The fracture toughness of these materials was investigated and improvements in toughness values of 100% over unmodified resin were demonstrated. The fracture-surface topology was examined using scanning electron and tapping-mode atomic force microscopies and shown to be related to the clay morphology of the system. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1137–1146, 2001
On the Inverse Mapping of the Formal Symplectic Groupoid of a Deformation Quantization

To each natural star product on a Poisson manifold M we associate an antisymplectic involutive automorphism of the formal neighborhood of the zero section of the cotangent bundle of M. If M is symplectic, this mapping is shown to be the inverse mapping of the formal symplectic groupoid of the star product. The construction of the inverse mapping involves modular automorphisms of the star product.
Surface, interface and thin film magnetism: an overview

Abstract A general view is presented of the state of the art in the field of surface, interface and thin film magnetism. The following items are discussed: (1) new growth techniques which produce atomically engineered novel materials; (2) characterization techniques to measure magnetic properties of these systems; and (3) computational advances which allow large complex calculations. Issues of fundamental and technological interest for possible future research are highlighted.
Hot-wire investigation of an unseparated shock-wave/turbulent boundary-layer interaction

Detailed hot-wire measurements of the longitudinal component of the mass-flow fluctuations have been made for an adiabatic fully attached shock-wave/turbulent boundary-layer interaction. The shock wave is induced by an 8-deg compression corner at a Mach number of 2.85 and a unit Reynolds number of 6.3 X10 m ~ l . The data indicate that the absolute mass-flow turbulence intensity increases abruptly through the shock wave, and continues to increase with further distance downstream. When nondimensionalized by the local freestream massflow rate the maximum turbulence intensity actually exceeds the upstream equilibrium value at the last measurement station. Measurements of the probability density of the fluctuations reveal only minor difference between the boundary-layer behavior upstream and downstream of the shock. A significant dip in the kurtosis was observed near the point of maximum intensity, which also coincided with the onset of intermittency.
Race, ideology, and the tea party: a longitudinal study.

The Tea Party movement, which rose to prominence in the United States after the election of President Barack Obama, provides an ideal context in which to examine the roles of racial concerns and ideology in politics. A three-wave longitudinal study tracked changes in White Americans’ self-identification with the Tea Party, racial concerns (prejudice and racial identification), and ideologies (libertarianism and social conservatism) over nine months. Latent Growth Modeling (LGM) was used to evaluate potential causal relationships between Tea Party identification and these factors. Across time points, racial prejudice was indirectly associated with movement identification through Whites’ assertions of national decline. Although initial levels of White identity did not predict change in Tea Party identification, initial levels of Tea Party identification predicted increases in White identity over the study period. Across the three assessments, support for the Tea Party fell among libertarians, but rose among social conservatives. Results are discussed in terms of legitimation theories of prejudice, the “racializing” power of political judgments, and the ideological dynamics of the Tea Party.
Characterization of Three-Dimensional Effects for the Rotating and Parked NREL Phase VI Wind Turbine

This paper addresses three-dimensional effects which are pertinent to wind turbine aerodynamics. Two computational models were applied to the National Renewable Energy Laboratory Phase VI Rotor under rotating and parked conditions, a vortex line method using a prescribed wake, and a parallelized coupled Navier-Stokes/vortex-panel solver (PCS). The linking of the spanwise distribution of bound circulation between both models enabled the quantification of three-dimensional effects with PCS. For the rotating turbine under fully attached flow conditions, the effects of the vortex sheet dissipation and replacement by a rolled-up vortex on the computed radial force coefficients were investigated. A quantitative analysis of both radial pumping and Coriolis effect, known as the Himmelskamp effect, was performed for viscous as well as in viscid flow. For the parked turbine, both models were applied at various pitch angles corresponding to fully attached as well as stalled flow. For partially stalled flow, computed results revealed a vortical structure trailing from the blade's upper surface close to the 40% radial station. This trailing vortex was documented as a highly unsteady flow structure in an earlier detached eddy simulation by another group, however, it was not directly observed experimentally but only inferred. Computed results show very good agreement with measured wind tunnel data for the PCS model. Finally, a new method for extracting three-dimensional airfoil data is proposed that is particularly well suited for highly stalled flow conditions.
Factors influencing graphene growth on metal surfaces

Graphene forms from a relatively dense, tightly bound C-adatom gas when elemental C is deposited on or segregates to the Ru(0001) surface. Nonlinearity of the graphene growth rate with C-adatom density suggests that growth proceeds by addition of C atom clusters to the graphene edge. The generality of this picture has now been studied by use of low-energy electron microscopy (LEEM) to observe graphene formation when Ru(0001) and Ir(111) surfaces are exposed to ethylene. The finding that graphene growth velocities and nucleation rates on Ru have precisely the same dependence on adatom concentration as for elemental C deposition implies that hydrocarbon decomposition only affects graphene growth through the rate of adatom formation. For ethylene, that rate decreases with increasing adatom concentration and graphene coverage. Initially, graphene growth on Ir(111) is like that on Ru: the growth velocity is the same nonlinear function of adatom concentration (albeit with much smaller equilibrium adatom concentrations, as we explain with DFT calculations of adatom formation energies). In the later stages of growth, graphene crystals that are rotated relative to the initial nuclei nucleate and grow. The rotated nuclei grow much faster. This difference suggests firstly, that the edge-orientation of the graphene sheets relative to the substrate plays an important role in the growth mechanism, and secondly, that attachment of the clusters to the graphene is the slowest step in cluster addition, rather than formation of clusters on the terraces.
Microwave Measurements of the Liquid Water Content of Atmospheric Aerosols.

Abstract A new method is described for the measurement of the dielectric constant of atmospheric aerosols. From these observations the free liquid water content of airborne particles can be deduced. An instrument to measure semi-continuously the dielectric constant of aerosols is discussed, and illustrative observations are given for urban air in Southern California and for marine and desert air at non-urban sites. The results taken during the fall of 1972 indicate that a significant fraction of the marine and urban aerosol observed is free water in the relative humidity range between 40 and 75%. The liquid water content in the aerosol correlates satisfactorily with the extinction coefficient for visible light, as measured with an integrating nephelometer.
Toward high-throughput synthesis of complex natural product-like compounds in the genomics and proteomics age.

In the age of high-throughput biology, novel genes and proteins are emerging quickly. The need for developing organic synthesis-derived methods that allow rapid access to polyfunctional, complex natural product-like compounds is growing constantly, largely because these small-molecule-based compounds serve as smart, powerful tools both in understanding the roles and functions of emerging biological targets and in validating their biological responses. Developing asymmetric synthesis-derived organic reactions on solid phase allows the synthesis of complex natural product-like compounds in a high-throughput manner. Solid phase organic synthesis is now commonly utilized in the library synthesis of rather simple compounds (i.e., compounds with no multiple stereogenic centers). With few exceptions, the synthesis of complex natural product-like derivatives is still in its infancy. Some recent efforts made in this area indicate opportunities yet to be explored.
Risk Management of Correlation Products

Trading units within the banking and dealer community that trade exotic instruments are well aware of the hazards of using traditional tools in analysing the risks resulting from positions taken in their specialised markets. The global risk management systems within these organisations have been slower to recognise the new risk profiles created by more recently traded exotic instruments. For traditional risks that are separable, the evaluation of risk at the individual trading units and the subsequent aggregation of risk across trading units captures the risks inherent in the portfolio. However, with non-traditional, non-separable risks, this division (by trading unit) and subsequent aggregation (by risk managers) of risks may obscure an increasing amount of risk found in the firm's trading operation.
Do cash flow variables improve the predictive accuracy of a Cox proportional hazards model for bank failure

Abstract This research uses the Cox proportional hazard model and bank cash flow information to determine whether adding cashflow information will improve current bankfailure prediction methods. In the corporate failure prediction literature it has been shown that including cash flow variables improves the performance of the models. This paper tests whether a similar result occurs for bank failure prediction models and discusses the policy implications of such results. The results of the study are mixed. Adding the cashflow information results in greater predictive accuracy in only the longer horizon models tested.
Mechanism of Antiferromagnetism in Dilute Alloys

Abstract A mechanism for the antiferromagnetic ordering of a dilute paramagnetic solute in a metal is proposed and discussed in relation to the phenomena that occur in copper-manganese alloys. Long-range antiferromagnetic order results from a static spin-density wave in the electron gas of the metal. This new state of the gas is dynamically self-sustaining as a result of the exchange potentials arising from the spin-density distribution. The paramagnetic solute atoms are then oriented by their exchange interaction with the spin-density wave. The resulting interaction energy more than compensates the increase in energy associated with the formation of the spin-density wave. The theory predicts correctly the magnitude and concentration-dependence of the critical temperature, the anomalous low-temperature specific heat and the anomalous electrical and magnetic properties of the alloys.
THE SYMBOLIC DYNAMICS OF TILING THE INTEGERS

A finite collectionP of finite sets tiles the integers iff the integers can be expressed as a disjoint union of translates of members ofP. We associate with such a tiling a doubly infinite sequence with entries fromP. The set of all such sequences is a sofic system, called a tiling system. We show that, up to powers of the shift, every shift of finite type can be realized as a tiling system.
Free radical addition to branched allylsilanes: stereoselective formation and elimination of β bromosilanes

Abstract Lewis acid-promoted free radical addition to 3-silyl-1-butenes occurs in good yield to give predominantly the cis -substituted alkene. The transfer reaction occurs by atom-transfer addition of the alkyl bromide precursor, an addition that occurs by Felkin–Anh control. Stereoselective anti elimination of the intermediate β-silylhalide gives the cis olefin.
Azimuthal Spoke Propagation in Hall Effect Thrusters

Spokes are azimuthally propagating perturbations in the plasma discharge of Hall effect thrusters (HETs) that travel in the $E \times B$ direction. The mechanisms for spoke formation are unknown, but their presence has been associated with improved thruster performance in some thrusters motivating a detailed investigation. The propagation of azimuthal spokes are investigated in a 6 kW HET by using high-speed imaging and azimuthally spaced probes. The spoke velocity is determined from high-speed image analysis using three methods with similar results. The spoke velocity for three discharge voltages (300, 400, and 450 V) and three anode mass flow rates (14.7, 19.5, and 25.2 mg/s) are between 1500 and 2200 m/s across a range of magnetic field settings. The spoke velocity is inversely dependent on magnetic field strength for lower B-fields and asymptotes at higher B-fields. Spoke velocities calculated from the probes are consistently higher by 30% or more. An empirically approximated dispersion relation of $\omega ^\alpha = {v}_{\rm ch}^\alpha k_{\theta }^\alpha - \omega _{\rm ch}^\alpha $ where $\alpha \ge 1$ yields a characteristic velocity that matches the ion acoustic speed for $\sim 5$ eV electrons which exist in the near-anode and near-field plume regions of the discharge.
Behavioral vs. Drug Treatment for Urge Urinary Incontinence in Older Women. A Randomized Controlled Trial

Context.—Urinary incontinence is a common condition caused by many factors with several treatment options. Objective.—To compare the effectiveness of biofeedback-assisted behavioral treatment with drug treatment and a placebo control condition for the treatment of urge and mixed urinary incontinence in older community-dwelling women. Design.—Randomized placebo-controlled trial conducted from 1989 to 1995. Setting.—University-based outpatient geriatric medicine clinic. Patients.—A volunteer sample of 197 women aged 55 to 92 years with urge urinary incontinence or mixed incontinence with urge as the predominant pattern. Subjects had to have urodynamic evidence of bladder dysfunction, be ambulatory, and not have dementia. Intervention.—Subjects were randomized to 4 sessions (8 weeks) of biofeedback-assisted behavioral treatment, drug treatment (with oxybutynin chloride, possible range of doses, 2.5 mg daily to 5.0 mg 3 times daily), or a placebo control condition. Main Outcome Measures.—Reduction in the frequency of incontinent episodes as determined by bladder diaries, and patients’ perceptions of improvement and their comfort and satisfaction with treatment. Results.—For all 3 treatment groups, reduction of incontinence was most pronounced early in treatment and progressed more gradually thereafter. Behavioral treatment, which yielded a mean 80.7% reduction of incontinence episodes, was significantly more effective than drug treatment (mean 68.5% reduction; P = .04) and both were more effective than the placebo control condition (mean 39.4% reduction; P,.001 and P = .009, respectively). Patient-perceived improvement was greatest for behavioral treatment (74.1% “much better” vs 50.9% and 26.9% for drug treatment and placebo, respectively). Only 14.0% of patients receiving behavioral treatment wanted to change to another treatment vs 75.5% in each of the other groups. Conclusion.—Behavioral treatment is a safe and effective conservative intervention that should be made more readily available to patients as a first-line treatment for urge and mixed incontinence. JAMA. 1998;280:1995-2000
Nucleosynthesis in neutron star atmospheres

The composition of neutron star atmospheres is calculated as a function of time including effects of diffusion, cooling and thermonuclear reactions. A seven-component nuclear reaction network with includes He4, C12, O16, Ne20, Mg24, Si28 and Fe56 is utilized. Neutron star models with different initial nuclear abundances are compared as to subsequent nucleosynthesis. It is found that the final abundances are independent of original composition assuming He4 as the major initial constituent. The final composition of the atmosphere is predominantly Fe56. Mass loss from an evolving neutron star is examined as a possible source of cosmic rays. It is found that a neutron star contributes only Fe56 significantly to the cosmic-ray spectrum.
Toward a psychology of positive youth development

This article analyzes the development of initiative as an exemplar of one of many learning experiences that should be studied as part of positive youth development. The capacity for initiative is essential for adults in our society and will become more important in the 21st century, yet adolescents have few opportunities to learn it. Their typical experiences during schoolwork and unstructured leisure do not reflect conditions for learning initiative. The context best suited to the development of initiative appears to be that of structured voluntary activities, such as sports, arts, and participation in organizations, in which youths experience the rare combination of intrinsic motivation in combination with deep attention. An incomplete body of outcome research suggests that such activities are associated with positive development, but the developmental processes involved are only beginning to be understood. One promising approach has recorded language use and has found that adolescents participating in effective organizations acquire a new operating language that appears to correspond to the development of initiative.
Correlations Between Central Massive Objects And Their Host Galaxies: From Bulgeless Spirals to Ellipticals

Recent observations reveal that a majority of galaxies contain a central massive object (CMO), either a supermassive black hole (SMBH) or a compact stellar nucleus, regardless of the galaxy mass or morphological type. The masses of these CMOs correlate tightly with those of the host galaxies, MCMO ≈ 0.002Mgal. Several recent studies argue that feedback from black holes can successfully explain the MBH-σ correlation in massive elliptical galaxies that contain SMBHs. However, puzzles remain in spirals or dwarf spheroids that do not appear to have black holes but instead harbor a compact central stellar cluster. Here we use three-dimensional, smoothed particle hydrodynamics simulations of both isolated and merging galaxies to study the formation and evolution of CMOs in bulgeless disk galaxies, and the transition of the CMO-host relations from late-type bulgeless spirals to early-type ellipticals. Our simulations show that the mass of the CMO correlates with that of the host galaxy in both isolated bulgeless spirals and in ellipticals formed through mergers, and that MCMO correlates with the global star formation efficiency in the galaxy. We find that the final mass of the CMO is dominated by the accreted mass, rather than the initial fragment mass, and that both the final accreted CMO mass and the recently formed stellar mass increase monotonically with the total mass of the galaxy. Our results suggest that the observed correlations may be established primarily by the depletion of gas in the central region by accretion and star formation, and may hold for all galaxy types. A systematic search for CMOs in the nuclei of bulgeless disk galaxies would offer a test of this conclusion.
Anomalous behavior of cumene cracking in small-pore catalysts

Abstract The reaction sequence in small-pore catalysts has been postulated to be as follows: adsorption of the reactant from the gas phase to the outside surface of the catalyst to form a condensed-type phase; diffusion of the condensed molecules along the pore walls analogous to surface diffusion, then reaction on active sites, followed by diffusion of the products to the external surface of the catalyst; finally, desorption of the products. This is in contrast to the conventional diffusion, adsorption, and reaction model which is suitable for larger-pore catalysts. Kinetic data from the cumene cracking reaction over REY zeolites are used in this work. The data were obtained at a wide range of temperatures, from 225 to 575°C, sufficient to include the regions of kinetic control and strong pore diffusion. Under these conditions and using the above model, the kinetic and diffusion parameters for cumene cracking are obtained. The intrinsic reaction rate constant and diffusion coefficient over REY zeolites are 2.5 × 106 cm3/g/s and 1.9 × 10−9 cm2/s at 500°C, with activation energies of 33 and 15 kcal/mol, respectively.
An orientifold from F theory

Abstract The massless spectrum of an orientifold of the IIB string theory is computed and shown to be identical to F theory on the Calabi-Yau threefold with h 11 = 51 and h 21 = 3. Target space duality is also considered in this model.
Numerical modeling of the late Cenozoic geomorphic evolution of Grand Canyon, Arizona

The late Cenozoic geomorphic evolution of Grand Canyon has been influenced by three primary tectonic and drainage adjustment events. First, 1 km of relief was produced along the Grand Wash–Wheeler Fault system beginning at 16.5 Ma. Second, the ancestral Colorado River became integrated with the lower Colorado River through Grand Canyon between 5.5 and 6 Ma. Third, the Colorado River was influenced by Plio-Quaternary normal faulting along the Hurricane and Toroweap Faults. Despite the relatively firm constraints available on the timing of these events, the geomorphic evolution of Grand Canyon is still not well constrained. For example, was there a deeply incised gorge in western Grand Canyon before Colorado River integration? How did incision rates vary through time and along the evolving river profile? What is the role of isostatic rebound and Plio-Quaternary faulting on the recent incision history of Grand Canyon? In this paper I describe the results of a process-based numerical modeling study designed to address these questions and to determine the plausibility of different proposed models for the erosional history of Grand Canyon. The numerical model I developed integrates the stream-power model for bedrock channel erosion with cliff retreat and the flexural-isostatic response to erosion. Two end-member paleodrainage and integration scenarios are considered. In the first model, I assume no incision in western Grand Canyon prior to 6 Ma. This model is equivalent to a lake-overtopping scenario for Colorado River integration. In this scenario, the model predicts that Colorado River integration at 6 Ma initiated the formation of a large (700 m) knickpoint that migrated headward at a rate of 100 km/Ma, resulting in rapid incision of western Grand Canyon down to the level of the Redwall Limestone from 6 to 4 Ma and incision of eastern Grand and Marble Canyons from 4 to 2 Ma. Widening of Grand Canyon by cliff retreat triggered flexural-isostatic rebound and renewed river incision of up to 350 m in Plio-Quaternary time according to this model. The model also indicates that Plio-Quaternary normal faulting significantly dampened incision rates in western Grand Canyon relative to eastern Grand Canyon. In the second paleodrainage scenario, I assume that a 13,000 km 2 paleodrainage crossed the Grand Wash–Wheeler Fault system at 16.5 Ma. The results of this model scenario indicate that relief production along the Grand Wash–Wheeler Fault system could have initiated the formation of a large (700 m) knickpoint that migrated headward at a rate of 15 km/Ma prior to 6 Ma to form a 150-km-long gorge in western Grand Canyon. Following integration at 6 Ma, the results of this model scenario are broadly similar to those of the first model, i.e., rapid incision through Grand and Marble Canyons from 6 to 2 Ma followed by cliff retreat, isostatic rebound, and fault-controlled incision. The results of the second model scenario illustrate that headward erosion of a proto–Grand Canyon could have been sufficient to capture the ancestral Colorado River east of the Shivwitz Plateau.
PROGNOSTIC FACTORS IN THE VISUAL REHABILITATION OF AGING PATIENTS

Of a group of 150 patients, 60 to 89 years of age, 84 percent were successfully using prescribed low vision aids; 16 percent had discontinued their use. The factors influencing success or failure that were investigated include ocular pathology, degree of residual vision, types of prescribed low vision aids, and psychological-emotional adjustment to life and to visual Impairment. The study revealed the importance of residual vision, the patient's life situation, and the extent of training in the use of the low vision aid, to the success of the prescription.
The role of O-type neutral lines in magnetic merging during substorms and solar flares

An analytical model of O-type configurations was derived, for visualizing the geometry and for numerical treatment of plasma flows. It was found that at a certain distance from the neutral line the mean particle motion became decoupled from that of magnetic field lines (which obey the MHD condition). The decoupling distance depended on initial conditions in momentum space, suggesting that the MHD approximation which averages out such conditions may not suffice for describing plasma dynamics near the neutral line. It was also found that after inflowing particles are decoupled from the field line motion, they go over to a mode of runaway acceleration along the neutral line. It is concluded that if merging occurs at an X-O pair, two particle populations may be expected - low energy particles accelerated adiabatically by earthward convection past the X-type line and high-energy particles convected towards the O-type line. The second acceleration process depends critically on the rapidity of merging and is therefore expected to vary considerably from event to event.
The ISIS project: real experience with a fault tolerant programming system

The ISIS project has developed a distributed programming toolkit and a collection of higher level applications based on these tools. ISIS is now in use at more than 300 locations world-wise. The lessons (and surprises) gained from this experience with the real world are discussed.
Mechanisms for nucleophilic aliphatic substitution at glycosides

Abstract Much of carbohydrate chemistry and biochemistry is centered on bond forming and bond breaking reactions at the anomeric carbon of glycosides. No single mechanism adequately covers the scope of these reactions, because differences in sugar substituents, stereochemistry, leaving groups, nucleophiles, and catalysts can influence the mechanistic pathway taken. The influence of solvent is only now beginning to become apparent in greater detail. Several methods exist to probe the mechanisms of these reactions; they include a variety of kinetic studies, including isotope effects, and computational methods. It has been found that typical reactions will uniquely utilize a mechanism somewhere within a continuum between A N D N and D N +A N mechanisms. With knowledge of the factors that determine the mechanism, synthetic method development will be furthered and a deeper understanding of biological catalysis is likely to be gained.
Some performance comparisons for a fluid dynamics code

Abstract The 3D transient motion of a buoyancy-driven perfect gas in an enclosure is computed by a FORTRAN program (BF3D). A combustion model for eventual inclusion in this program is under development. BF3D changes slowly, has a long lifetime, and is run fairly infrequently. Typical runs have large storage and CPU requirements. BF3D runs on large supercomputers but the newer mini-supercomputers appear to be suitable also and may be advantageous for ease of access and usage. Programming workstations are convenient for development. Comparisons of BF3D on selected supercomputers, mini-supercomputers, scientific workstations and conventional mainframes are presented for the purpose of making partial benchmark data available to the computing public.
Oxidatively intercepting Heck intermediates: Pd-catalyzed 1,2- and 1,1-arylhalogenation of alkenes.

This communication describes the development of two Pd-catalyzed reactions for the arylchlorination of diverse α-olefins by oxidatively intercepting Heck intermediates. Depending on the nature of the oxidant and the reaction conditions, these transformations can afford synthetically useful 1,1- or 1,2-arylchlorinated products in good yields and with good to excellent selectivities. Preliminary mechanistic investigations show that the selectivity of these reactions can be rationally tuned (i) by controlling the relative rates of oxidative functionalization versus β-hydride elimination from equilibrating PdII−alkyl species and (ii) by π-benzyl stabilization of Pd intermediates.
Elementary Reaction Models for CO Electrochemical Oxidation on an Ni/YSZ Patterned Anode

Analysis of recent experimental impedance spectra and polarization curves of nickel/yttria-stabilized zirconia (Ni/YSZ) patterned anode of a solid oxide fuel cell (SOFC) are used to determine the limiting steps in CO electrochemical oxidation kinetics. A comprehensive 1D model is proposed for the prediction of the steady-state polarization curve of a patterned anode SOFC. The model incorporates gas species adsorption/desorption with surface diffusion and one of two possible charge transfer reaction steps: O charge transfer reaction [O2− (YSZ)+(Ni)+↔(YSZ)+O(Ni)+2e− ], or CO charge transfer reaction [O2− (YSZ)+CO(Ni)↔(YSZ)+CO2 (Ni)+2e− ]. We show that the mechanism incorporating charge transfer between adsorbed CO and oxygen vacancy is able to better predict the experimental data. We estimate some of the model parameters, such as the exchange current density and charge transfer coefficient by fitting the simulation of the polarization curves to the experimental data.Copyright © 2010 by ASME
The cosmology of composite inelastic dark matter

Composite dark matter is a natural setting for implementing inelastic dark matter - the O(100 keV) mass splitting arises from spin-spin interactions of constituent fermions. In models where the constituents are charged under an axial U(1) gauge symmetry that also couples to the Standard Model quarks, dark matter scatters inelastically off Standard Model nuclei and can explain the DAMA/LIBRA annual modulation signal. This article describes the early Universe cosmology of a minimal implementation of a composite inelastic dark matter model where the dark matter is a meson composed of a light and a heavy quark. The synthesis of the constituent quarks into dark hadrons results in several qualitatively different configurations of the resulting dark matter composition depending on the relative mass scales in the system.
The Schrödinger-HJW Theorem

A concise presentation of Schrodinger's ancilla theorem (Proc. Camb. Phil. Soc. 32, 446 (1936)) and its several recent rediscoveries.