cssi/SciSciGPT-SciSciNet huggingface dataset:
A twisted Laurent series ring that is a noncrossed product

The striking results on noncrossed products were their existence (Amitsur [1]) and the determination of ℚ(t) and ℚ((t)) as their smallest possible centres (Brussel [3]). This paper gives the first fully explicit noncrossed product example over ℚ((t)). As a consequence, the use of deep number theoretic theorems (local-global principles such as the Hasse norm theorem and density theorems) in order to prove existence is eliminated. Instead, the example can be verified by direct calculations. The noncrossed product proof is short and elementary.
Zero-temperature dynamics of 2D and 3D Ising ferromagnets

We consider zero-temperature, stochastic Ising models σt with nearest-neighbour interactions in two and three dimensions. Using both symmetric and asymmetric initial configurations σ0, we study the evolution of the system with time. We examine the issue of convergence of σt and discuss the nature of the final state of the system. By determining a relation between the median number of spin flips per site ν, the probability p that a spin in the initial spin configuration takes the value +1, and lattice size L, we conclude that in two and three dimensions, the system converges to a frozen (but not necessarily uniform) state when p ≠ 1/2. Results for p = 1/2 in three dimensions are consistent with the conjecture that the system does not evolve towards a fully frozen limiting state. Our simulations also uncover 'striped' and 'blinker' states first discussed by Spirin et al (2001 Phys. Rev. E 63 036118), and their statistical properties are investigated.
Engineering and technology students’ perceptions of courses

As cultural, social, political and economic changes take place, the secondary or high school curriculum should reflect and respond to changing needs and aspirations of students. Technology Education has been proactive in this arena as it has transformed over the decades to meet ever-changing societal needs. The most recent change to the discipline has been to add engineering and, as a result, adopting a new name and curriculum-Engineering and Technology Education. The added component and name change in Technology Education is causing discussions about what the new direction means, what professional preparation changes will be incurred, and what work graduating students will be prepared to do. In light of these changes, this study investigated perceptions of high school students in the United States of America about engineering and technology courses they take. To investigate whether students’ perceptions are in accord with current changes in Engineering and Technology Education, 316 students enrolled in engineering and technology courses in Georgia schools that have an affiliation with the Georgia Engineering and Technology Education Association (GETEA) were surveyed. According to data analyses, students’ perceptions can be divided into two factors. Educational Value of Course (factor 1) was extracted from statements measuring the degree to which the courses prepare students for employment and provide them with information regarding future employment. Personal Relevance of Course (factor 2) was derived from statements measuring students’ perceptions about links between engineering and technology education and their personal lives. Such findings suggest these students valued their engineering and technology courses, planned to continue their education, made good grades, and had varied types of career expectations for jobs such as design engineers and architects.
Separated Flow in a Low-Speed Two-Dimensional Cascade: Part II—Cascade Performance

This study was conducted for the purpose of providing a more fundamental understanding of separated flow in cascades and to provide performance data for fully stalled blade rows. Cascades of a single blade geometry and solidity of unity were studied for three stagger angles and the full range of angle of attack extending well into the stalled flow regime. The Reynolds number was also varied for a limited number of cases. Results from velocity and pressure measurements made in the cascade and the overall cascade performance evaluated from these measurements are presented. In addition, results from a numerical simulation of the flow through a cascade of flat plate airfoils are used to illustrate further the effects of blade stagger and to define the correct limits for the cascade performance. The results indicate that the slope of the total pressure loss versus angle of attack curve for the flow immediately downstream of the cascade is steeper for cascades with greater stagger. The normal force coefficient was found to increase to a peak value near the angle of attack where full leading edge stall first occurs. A further increase in angle of attack results in a decline in the normal force coefficient.more » The peak value of the normal force coefficient is greater and occurs at a higher angle of attack for the cascades with smaller stagger.« less
High-latitude forcing of interior ocean δ13C

[1] Transit time distribution probability density functions (TTDs) are used to investigate the possible role of changing boundary conditions in driving the δ13C signal in the interior of a steady state ocean. We use idealized examples to investigate the general question of how a conservative tracer propagates from the surface ocean to interior ocean and to illustrate how a given tracer boundary signal will be “filtered” with increasing distance from its source region. We show that tracers in the deep southeast Atlantic Ocean will respond much more strongly to changes in the surface Southern Ocean than to changes in the high-latitude North Atlantic, while the opposite is true for waters at intermediate depths. The impact of a change in the Southern Ocean surface δ13C on a profile from the western South Atlantic is estimated using model-derived transit time distributions, and it is shown that significant deep ocean δ13C variations can be expected on glacial-interglacial timescales, even under a steady state circulation regime. Records of δ13C from the high-latitude North Atlantic and Southern Ocean are used as a proxy for glacial-interglacial changes in the surface ocean boundary condition in regions of deepwater formation. By convolving these high-latitude boundary conditions with model-derived TTDs, we are able to explain a significant part of the observed variability in benthic δ13C records spanning the last glacial cycle(s) from locations as diverse as the equatorial Atlantic Ocean, the Cape Basin, and the equatorial Pacific. This suggests that changing boundary conditions may be driving a significant fraction of benthic δ13C variability previously attributed to changes in ocean circulation. Furthermore, we show that our results predict a slightly higher δ13C than observed in high-productivity regions, consistent with the concept of a productivity-induced low-δ13C overprint.
Cien años de Soledades. Galerías. Otros poemas : Presente y pasado en Antonio Machado

Machado was extremely interested in the use of non-linear temporal sequences, which explains in part his emphasis a la Bergson on repetition, the intellectual paradoxes arising from the leaps backwards and forwards in the subject’s consciousness, and even his view of the past as a creation in the present using the subjective materials of memory. In this essay I adopt advisedly Ortega’s concept of the «dialectical series» to connect the critique of biographical time found in Soledades , which revolves around the binomial «history»/«legend», with the poet’s preference for the time of performative enunciation over the time of the anecdote’s content. To this end, I will discuss in detail a handful of poems drawn form the 1902-1903 and 1907 editions of Soledades .
Enumerating contingency tables via random permanents

Given m positive integers R = (ri), n positive integers C = (cj) such that Σri = Σcj = N, and mn non-negative weights W=(wij), we consider the total weight T=T(R, C; W) of non-negative integer matrices D=(dij) with the row sums ri, column sums cj, and the weight of D equal to $\prod w_{ij}^{d_{ij}}$ . For different choices of R, C, and W, the quantity T(R,C; W) specializes to the permanent of a matrix, the number of contingency tables with prescribed margins, and the number of integer feasible flows in a network. We present a randomized algorithm whose complexity is polynomial in N and which computes a number T′=T′(R,C;W) such that T′ ≤ T ≤ α(R,C)T′ where $\alpha(R,C) = \min \bigl\{\prod r_i! r_i^{-r_i}, \ \prod c_j! c_j^{-c_j} \bigr\} N^N/N!$ . In many cases, ln T′ provides an asymptotically accurate estimate of ln T. The idea of the algorithm is to express T as the expectation of the permanent of an N × N random matrix with exponentially distributed entries and approximate the expectation by the integral T′ of an efficiently computable log-concave function on mn.
Coordinating macroeconomic policy in a simple AK growth model

Abstract Modern theories of government finance stress the importance of an economy’s fiscal deficits in determining the course of monetary policy. Modern growth theory stresses the role of monetary factors in economic growth. This paper explores how these two are interrelated, using a simple AK growth model, one with money, reserve requirements, and government debt. We provide a comprehensive look at the coordination of macroeconomic policy and its effects on long-run growth under three alternative coordinating arrangements. We uncover some unconventional results regarding the relationship between growth and a number of policy variables; these rest squarely on the constraint of the coordination process.
DIRECT OXIDATION OF ETHYLENE TO ACETALDEHYDE IN A HOLLOW FIBER MEMBRANE REACTOR

A hollow fiber membrane reactor, which resembles a tube-and-shell heat exchanger, was developed for homogeneous catalytic reactions with gas reactants and products. The gas stream flows through the...
Insight into the unusual reactions of stabilized phosphorus ylides with lactols. A specific intramolecular hydroxyl group effect leads to high z-selectivity.

Abstract In reactions with stabilized ylides, γ-lactols of ribo configuration afford 90% Z-olefins whereas γ-lactols of allo configuration afford predominantly E-olefins. Lactols of arabino configuration give intermediate results. The unusual results in the ribo series completely disappear on protection of the γ-hydroxyl group.
Patterns of capital flows to emerging markets : a theoretical perspective

This paper reviews some of the basic patterns of international capital flows to emerging markets in recent years, including the composition of capital flows, intraregional flow patterns, and the geographical distribution of the flows. A theoretical model that sheds new light on these observed patterns is developed. This model focuses on the cost of financing aspect of capital flows, and shows that the patterns of capital flows are influenced by the combined effects of financial market development and growth potential in the recipient countries. The theoretical predictions of the model are shown to be consistent with the stylized facts.
Spatial imaging of magnetically patterned nuclear spins in GaAs

We exploit ferromagnetic imprinting to create complex laterally defined regions of nuclear spin polarization in lithographically patterned MnAs/GaAs epilayers grown by molecular beam epitaxy. A time-resolved Kerr rotation microscope with \ensuremath{\sim}1 \ensuremath{\mu}m spatial resolution uses electron spin precession to directly image the GaAs nuclear polarization. These measurements indicate that the polarization varies from a maximum under magnetic mesas to zero several microns from the mesa perimeter, resulting in large $(\ensuremath{\sim}{10}^{4}\mathrm{T}/\mathrm{m})$ effective field gradients. The results reveal a flexible scheme for lateral engineering of spin-dependent energy landscapes in the solid state.
Characterization of Plasma Synthesized Vertical Carbon Nanofibers for Nanoelectronics Applications

We report on the material characterization of carbon nanofibers (CNFs) which are assembled into a three-dimensional (3D) configuration for making new nanoelectromechanical systems (NEMS). High-resolution scanning electron microscopy (SEM) and x-ray electron dispersive spectroscopy (XEDS) are employed to decipher the morphology and chemical compositions of the CNFs at various locations along individual CNFs grown on silicon (Si) and refractory nitride (NbTiN) substrates, respectively. The measured characteristics suggest interesting properties of the CNF bodies and their capping catalyst nanoparticles, and growth mechanisms on the two substrates. Laser irradiation on the CNFs seems to cause thermal oxidation and melting of catalyst nanoparticles. The structural morphology and chemical compositions of the CNFs revealed in this study should aid in the applications of the CNFs to nanoelectronics and NEMS.
Two-stream theory of diffusing light spectroscopies

Abstract A theory for the propagation of light through a randomly scattering slab is developed that does not take advantage of a diffusion approximation but can be solved analytically. The treatment allows for scattering anisotropy and boundary reflectivity to be incorporated in a straightforward fashion for slabs of arbitrary thickness. Predictions are found for both the transmission probability and the electric field autocorrelation function which, respectively, can be used to analyze diffuse-transmission spectroscopy and diffusing-wave spectroscopy data more accurately.
Response Time in a Teletext System: An Individual User's Perspective

Teletext is a one-way, broadcast-delivery information system. Pages of information are continuously broadcast to the users. User terminals monitor the broadcast stream and requested pages, once recognized, are captured and stored. Teletext systems possess many attractive features. Among them are simplicity of operation and insensitivity of system performance to user loads. Previous research has considered the issue of response time optimization in teletext systems. In those studies, response time was averaged over the entire user population. In this paper, we analyze an individual user's response time experience. Needless to say, this provides a better gauge of the quality of service being delivered. In addition, this perspective provides the appropriate framework for evaluating strategies that take advantage of user terminal storage capabilities to improve response time performance. To demonstrate this, one such strategy is developed and analyzed. Numerical examples that illustrate the use of the paper's results are also presented.
The expected number of zeros of a random system of $p$-adic polynomials

We study the simultaneous zeros of a random family of $d$ polynomials in $d$ variables over the $p$-adic numbers. For a family of natural models, we obtain an explicit constant for the expected number of zeros that lie in the $d$-fold Cartesian product of the $p$-adic integers. Considering models in which the maximum degree that each variable appears is $N$, this expected value is $$ p^{d \lfloor \log_p N \rfloor} \left(1 + p^{-1} + p^{-2} + \cdots + p^{-d}\right)^{-1} $$ for the simplest such model.
Fiber metal acoustic material for gas turbine exhaust environments

FELTMETAL fiber metal acoustic materials function as broad band acoustic absorbers. Their acoustic energy absorbance occurs through viscous flow losses as sound waves pass through the tortuous pore structure of the material. Exhaust gas noise attenuation requirements are reviewed. Their selection process for higher performance materials is discussed. A new FELTMETAL fiber metal acoustic material has been designed for use in gas turbine auxiliary power unit exhaust environments without supplemental cooling. The physical and acoustic properties of mesh supported fiber metal acoustic medium FM 827 are discussed. Exposure testing was conducted under conditions which simulated auxiliary power unit operation. Weight gain and tensile strength data as a function of time of exposure at 650{sup 0}C (1202{sup 0}F) are reported. Fabrication of components with fiber metal acoustic materials is easily accomplished using standard roll forming and gas tungsten arc welding practices.
On the Spectral Density of the Wavelet Coefficients of Long-Memory Time Series with Application to the Log-Regression Estimation of the Memory Parameter

In the recent years, methods to estimate the memory parameter using wavelet analysis have gained popularity in many areas of science. Despite its widespread use, a rigorous semi-parametric asymptotic theory, comparable to the one developed for Fourier methods, is still missing. In this contribution, we adapt the classical semi-parametric framework introduced by Robinson and his co-authors for estimating the memory parameter of a (possibly) non-stationary process. As an application, we obtain minimax upper bounds for the log-scale regression estimator of the memory parameter for a Gaussian process and we derive an explicit expression of its variance.
Digital Imaging For Radiation Therapy Verification

A linear diode array was used to scan a radiation field for pulsed high-energy x-ray imaging. With a signal of about 50 picocoulombs of charge from each diode for each beam pulse, the signal to noise ratio for an image of an open field was 119. An image of a porcine femur in a wax phantom was obtained by scanning the transmitted radiation. The resultant electronic image was superior in quality when compared to the standard radiotherapy port film. The simplicity of the detector system has demonstrated the feasibility of constructing an electronic portal imaging system for clinical use.
Alternative fuel spray behavior

The effects of alternative fuels on the combustion characteristics of a liquid fuel spray are examined. Fuel properties are varied and the effects of these variations on the structure (drop histories, temperatures, and species concentrations) of the spray flame are calculated. Also, a comparison is made of the differences in two spray flames fueled by a standard NATO fuel and a proposed alternative fuel. The calculations are performed using a reacting, two-phase, two-dimensional flow code that utilizes a Lagrangian calculation of droplet trajectories and an Eulerian approach for the gas-phase flowfield. Interactions between the drops and the gas phase are accomplished through the particle-source-in-cell technique with exchange of mass, momentum, and energy between the two phases. A global reaction scheme is used with the reaction rate determined by the minimum of either an Arrhenius rate or mixing rate. Fuel property changes that affect droplet size and volatility are shown to have significant effects on droplet trjectory patterns. However, for the flowfield examined in this paper (where the fuel spray core is very rich and the mixing of air with the fuel occurs at a relatively slow rate), these trajectory changes only moderately modify the fuel vaporization pattern within the spray.more » 20 refs.« less
MPI photoelectron spectroscopy of ungerade excited states of acetylene: Intermediate state mixing and ion state selection

Three photon resonant, four photon (3+1) ionization spectroscopy and photoelectron spectroscopy have been used to study the ungerade excited states of acetylene in the energy range from 74 500 to 90 000 cm−1. Sharp bands from the nR (π3u nsσg) and 1Φu (π3u ndδg) Rydberg series dominate the MPI spectrum. A large number of Rydberg and valence states which are prominent in VUV absorption spectra are absent or weak in MPI studies. These weak bands are only observable under high power conditions, which suggests that nonradiative decay is rapid enough to depopulate these states before ionization occurs. The photoelectron results provide further insight into the nature of the excited states. Ionization through the sharp bands occurs via Δν=0 Franck–Condon transitions, resulting in ions in a single vibrational state. Ionization through bands which are mixed results in complicated ion vibrational distributions including excitation of both cis and trans bends.
Pattern avoidance and smoothness of closures for orbits of a symmetric subgroup in the flag variety

Abstract We give a pattern avoidance criterion to classify the orbits of Sp ( p , C ) × Sp ( q , C ) (resp. GL ( n , C ) ) on the flag variety of type C p + q (resp. D n ) with rationally smooth closure. We show that all such orbit closures fiber (with smooth fiber) over a smaller flag variety, and hence are in fact smooth. In addition we prove that the classification is insensitive to isogeny.
Optimization of catalyst enantioselectivity and activity using achiral and meso ligands.

The optimization of asymmetric catalysts for enantioselective synthesis has conventionally revolved around the synthesis and screening of enantiopure ligands. In contrast, we have optimized an asymmetric reaction by modification of a series of achiral ligands. Thus, employing (S)-3,3‘-diphenyl BINOL [(S)-Ph2-BINOL] and a series of achiral diimine and diamine activators in the asymmetric addition of alkyl groups to benzaldehyde, we have observed enantiomeric excesses between 96% (R) and 75% (S) of 1-phenyl-1-propanol. Some of the ligands examined have low-energy chiral conformations that can contribute to the chiral environment of the catalyst. These include achiral diimine ligands with meso backbones that adopt chiral conformations, achiral diimine ligands with backbones that become axially chiral on coordination to metal centers, achiral diamine ligands that form stereocenters on coordination to metal centers, and achiral diamine ligands with pendant groups that have axially chiral conformations. Additio...
Direct assessment of children’s social-emotional comprehension.

Social-emotional comprehension includes the ability to encode, interpret, and reason about social-emotional information. The better developed children's social-emotional comprehension, the more positive their social interactions and the better their peer relationships. Many clinical tools exist to assess children's social behavior. In contrast, fewer clinically interpretable tools are available to assess children's social-emotional comprehension. This study evaluated the psychometric properties of a group of direct assessments of social-emotional comprehension. Scores on these assessments reflected children's performance on challenging tasks that required them to demonstrate their social-emotional comprehension. In 2 independent samples, including a general education school sample (n = 174) and a clinic sample (n = 119), this study provided evidence that (a) individual assessments yield variably reliable scores, (b) composite scores are highly reliable, (c) direct assessments demonstrate a theoretically coherent factor structure and convergent and discriminant validity, and (d) composite scores yield expected age- and diagnostic-group differences. Implications for clinical practice, theory, and assessment development are discussed.
Electron electric dipole moment experiment using electric-field quantized slow cesium atoms

A proof-of-principle electron electric dipole moment (e-EDM)experiment using slow cesium atoms, nulled magnetic fields, and electricfield quantization has been performed. With the ambient magnetic fieldsseen by the atoms reduced to less than 200 pT, an electric field of 6MV/m lifts the degeneracy between states of unequal lbar mF rbar and,along with the low (approximately 3 m/s) velocity, suppresses thesystematic effect from the motional magnetic field. The low velocity andsmall residual magnetic field have made it possible to induce transitionsbetween states and to perform state preparation, analysis, and detectionin regions free of applied static magnetic and electric fields. Thisexperiment demonstrates techniques that may be used to improve the e-EDMlimit by two orders of magnitude, but it is not in itself a sensitivee-EDM search, mostly due to limitations of the laser system.
Modular overconstrained weak-link mechanism for ultraprecision motion control

Abstract We have designed and constructed a novel miniature overconstrained weak-link mechanism that will allow positioning of two crystals with better than 50 nrad angular resolution and nanometer linear driving sensitivity. The precision and stability of this structure allow the user to align or adjust an assembly of crystals to achieve the same performance as does a single channel-cut crystal, so we call it an “artificial channel-cut crystal.” Unlike the traditional kinematic linear spring mechanisms, the overconstrained weak-link mechanism provides much higher structure stiffness and stability. Using a laminar structure configured and manufactured by chemical etching and lithography techniques, we are able to design and build a planar-shape, high stiffness, high precision weak-link mechanism. In this paper, we present recent developments for the overconstrained weak-link mechanism. Applications of this new technique to synchrotron radiation instrumentation are also discussed.
Global Administrative Law: The View from Basel

International law-making by sub-national actors and regulatory networks of bureaucrats has come under attack as lacking in accountability and legitimacy. Global administrative law is emerging as an approach to understanding what international organizations and national governments do, or ought to do, to respond to the perceived democracy deficit in international law-making. This article examines the Basel Committee on Banking Supervision, a club of central bankers who meet to develop international banking capital standards and to develop supervisory guidance. The Basel Committee embodies many of the attributes that critics of international law-making lament. A closer examination, however, reveals a structure of global administrative law inherent in the Basel process that could be a model for international law-making with greater accountability and legitimacy.
Xanthine oxidoreductase-catalyzed reactive species generation: A process in critical need of reevaluation.

Nearly 30 years have passed since the discovery of xanthine oxidoreductase (XOR) as a critical source of reactive species in ischemia/reperfusion injury. Since then, numerous inflammatory disease processes have been associated with elevated XOR activity and allied reactive species formation solidifying the ideology that enhancement of XOR activity equates to negative clinical outcomes. However, recent evidence may shatter this paradigm by describing a nitrate/nitrite reductase capacity for XOR whereby XOR may be considered a crucial source of beneficial •NO under ischemic/hypoxic/acidic conditions; settings similar to those that limit the functional capacity of nitric oxide synthase. Herein, we review XOR-catalyzed reactive species generation and identify key microenvironmental factors whose interplay impacts the identity of the reactive species (oxidants vs. •NO) produced. In doing so, we redefine existing dogma and shed new light on an enzyme that has weathered the evolutionary process not as gadfly but a crucial component in the maintenance of homeostasis.
A simple condition for bounded displacement

Abstract We study separated nets Y that arise from primitive substitution tilings of R d . We show that the question whether Y is a bounded displacement of Z d or not can be reduced, in many cases, to a simple question on the eigenvalues and eigenspaces of the substitution matrix.
Frozen Flux Superconductors

We propose a new class of composite superconductors with embedded magnetic nanoparticles/nanorods. These nanomagnets can create a thermodynamically stable, frozen, dense flux line network. We discuss the methods of fabrication of these novel materials. We show that due to the frozen flux created by magnetic nanorods, the critical current in this composite superconductor can be higher than in the superconductor with a comparable density of columnar defects.
Determination of selected perfluorinated alkyl acids and persistent organic pollutants from a small volume human serum sample relevant for epidemiological studies.

Abstract A simple and fast method is presented for the determination of selected persistent organic pollutants (POPs) and perfluorinated alkyl acids (PFAAs), a subgroup of per- and polyfluorinated alkyl substances (PFAS) from a single 200 μl aliquot of serum. Sample pretreatment starts with dispersive solid phase extraction of POPs to dichloromethane–hexane, which is immediately poured to cleanup column. POPs are eluted from column and concentrated for GC–MS/MS analysis. PFAAs are trapped to dispersant and are then extracted with ammonium acetate in methanol, concentrated and analysed with LC–MS/MS. For POPs, the limit of detection (LOD) ranged from 1.6 to 17 pg/ml. Oxychlordane and dichlorodiphenyltrichloroethane had LODs in the upper end of this range as they were more labile and prone for interferences in the GC–MS/MS. For PFAAs, the LOD range from 0.027 to 0.068 ng/ml. For POPs, the accuracy from Standard Reference Materials SRM 1589a and Arctic Monitoring and Assessment Programme (AMAP) intercalibration samples range from 74 to 127% and the repeatability (relative standard deviation, RSD%) from 2.0 to 15%. For PFAAs, the accuracy from AMAP samples ranged from 90 to 110% and from LOQ level spiked serum samples from 72 to 133%. Repeatability from AMAP and LOQ samples ranged from 1.6 to 7.3% and 5.5 to 15%, respectively. The presented method is useful in epidemiological studies where only limited amount of serum is available.
Discovery of a 3.6 hr Eclipsing Luminous X-Ray Binary in the Galaxy NGC 4214

We report the discovery of an eclipsing X-ray binary with a 3.62-hr period within 24 arcsec of the center of the dwarf starburst galaxy NGC 4214. The orbital period places interesting constraints on the nature of the binary, and allows for a few very different interpretations. The most likely possibility is that the source lies within NGC 4214 and has an X-ray luminosity of up to 7e38. In this case the binary may well be comprised of a naked He-burning donor star with a neutron-star accretor, though a stellar-mass black-hole accretor cannot be completely excluded. There is no obvious evidence for a strong stellar wind in the X-ray orbital light curve that would be expected from a massive He star; thus, the mass of the He star should be <3-4 solar masses. If correct, this would represent a new class of very luminous X-ray binary----perhaps related to Cyg X-3. Other less likely possibilities include a conventional low-mass X-ray binary that somehow manages to produce such a high X-ray luminosity and is apparently persistent over an interval of years; or a foreground AM Her binary of much lower luminosity that fortuitously lies in the direction of NGC 4214. Any model for this system must accommodate the lack of an optical counterpart down to a limiting magnitude of 22.6 in the visible.
Optical Measurement of Unducted Fan Blade Deflections

A nonintrusive optical method for measuring unducted fan (or propeller) blade deflections is described and evaluated. Deflection of a point at the leading edge and a point at the trailing edge in a plane nearly perpendicular to the pitch axis is obtained with a single light beam generated by a low-power, helium-neon laser. Measured static deflections from a series of high-speed wind tunnel tests of a counterrotating unducted fan model are compared with available predicted deflections, which also are used to evaluate systematic errors
Three-body helicity formalism applied to pion-deuteron scattering☆

Abstract We apply Wick's three-body helicity formalism, to covariantly reduce the relativistic Faddeev equations that describe pion-deuteron elastic scattering, obtaining a set of equations that satisfy two- and three-body unitarity and are Lorentz invariant with regard to both the space and the spin variables. We use all the pion-nucleon S and P-wave channels and the two nucleon-nucleon S-wave channels as input, to give a good description of the data for pion kinetic energies in the region from 142 MeV up to 512 MeV.
Synthesis of 5-Iodo-1,4-disubstituted-1,2,3-triazoles Mediated by in Situ Generated Copper(I) Catalyst and Electrophilic Triiodide Ion

Mixing copper(II) perchlorate and sodium iodide solutions results in copper(I) species and the electrophilic triiodide ions, which collectively mediate the cycloaddition reaction of organic azide and terminal alkyne to afford 5-iodo-1,4-disubstituted-1,2,3-triazoles. One molar equivalent of an amine additive is required for achieving a full conversion. Excessive addition of the amine compromises the selectivity for 5-iodo-1,2,3-triazole by promoting the formation of 5-proto-1,2,3-triazole. Based on preliminary kinetic and structural evidence, a mechanistic model is formulated in which a 5-iodo-1,2,3-triazole is formed via iodination of a copper(I) triazolide intermediate by the electrophilic triiodide ions (and possibly triethyliodoammonium ions). The experimental evidence explains the higher reactivity of the in situ generated copper(I) species and triiodide ion in the formation of 5-iodo-1,2,3-triazoles than that of the pure forms of copper(I) iodide and iodine.
Breast Magnetic Resonance Imaging: Current Clinical Indications

Breast magnetic resonance (MR) is highly sensitive in the detection of invasive breast malignancies. As technology improves, as interpretations and reporting by radiologists become standardized through the development of guidelines by expert consortiums, and as scientific investigation continues, the indications and uses of breast MR as an adjunct to mammography continue to evolve. This article discusses the current clinical indications for breast MR including screening for breast cancer, diagnostic indications for breast MR, and MR guidance for interventional procedures.
Epoxidation of α,β-unsaturated ketones with sodium perborate

Abstract α,β-Unsaturated ketones are rapidly converted to epoxyketones at room temperature in aqueous sodium perborate in the presence of a phase transfer catalyst. Organic solvents can be used to modify the rate of epoxidation.
Discrete Fourier Restriction Associated with KdV Equations

In this paper, we consider a discrete restriction associated with KdV equations. Some new Strichartz estimates are obtained. We also establish the local well-posedness for the periodic generalized Korteweg–de Vries equation with nonlinear term F(u)∂xu provided F∈C5 and the initial data ϕ∈Hs with s>1∕2.
Large‐scale properties of the interplanetary magnetic field

Our knowledge of the large-scale properties of the interplanetary magnetic field is reviewed. The early theoretical work of Parker is presented, along with the observational evidence supporting his Archimedes spiral model. The variations present in the interplanetary magnetic field from the spiral angle are related to structures in the solar wind. The causes of these structures are found to be either nonuniform radial solar wind flow or the time evolution of the photospheric field. The coronal magnetic models are related to the connection between the solar magnetic field and the interplanetary magnetic field. The direct extension of solar field-magnetic nozzle controversy is discussed, along with the coronal magnetic models. The effect of active regions on the interplanetary magnetic field is discussed with particular reference to the evolution of interplanetary sectors. The variation of the interplanetary magnetic field magnitude is shown throughout the solar cycle. The percentage of time the field magnitude is greater than 10 γ is shown to closely parallel sunspot number. The suggested influence of the sun's polar field on the interplanetary field and alternative views of the magnetic field structure out of the ecliptic plane are presented. In addition, a variety of significantly different interplanetary field structures are discussed.
Lattice Boltzmann simulation to study multiple bubble dynamics

Lattice Boltzmann method (LBM) has been used in this study to understand the behavior of bubble motion and bubble coalescence in liquids. Highly isotropic gradient vectors have been obtained on a lattice for two-phase simulations using LBM. For a fully periodic domain, bubble dynamics and shape for a single bubble and multiple bubbles are dependent on Eotvos number, Reynolds number and Morton number. For single bubble simulations, computations were done for high Eotvos and low to moderate Reynolds numbers, and the results are matched with the experimentally quantified flow visualization chart. The drag coefficient for single bubble motion under buoyancy for both two- and three-dimensional simulations compares well with existing correlations. For multiple bubbles, the bubble dynamics is dictated by the vortex pattern of the leading bubble, which allows the bubbles to coalesce. Coalescence can be described as a three stage process: collision; drainage of the liquid film between adjacent bubbles to a critical thickness; and rupture of this thin film of liquid. Such simulations have also been run for different configurations of the initial bubble distribution for both in-line and staggered bubble configuration to show the effect of vortex shedding on the oscillatory motion of the bubbles and subsequent coalescence.
On Growth Types of Quotients of Coxeter Groups by Parabolic Subgroups

The principal objects studied in this note are infinite, non-affine Coxeter groups W. A well-known result of de la Harpe asserts that such groups have exponential growth. We study the growth type of quotients of W by parabolic subgroups and by a certain class of reflection subgroups. Our main result is that these quotients have exponential growth as well.
VALIDATION OF KEPLER'S MULTIPLE PLANET CANDIDATES. II. REFINED STATISTICAL FRAMEWORK AND DESCRIPTIONS OF SYSTEMS OF SPECIAL INTEREST

We extend the statistical analysis performed by Lissauer et al. in 2012, which demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) represents true transiting planets, and we develop therefrom a procedure to validate large numbers of planet candidates in multis as bona fide exoplanets. We show that this statistical framework correctly estimates the abundance of false positives already identified around Kepler targets with multiple sets of transit-like signatures based on their abundance around targets with single sets of transit-like signatures. We estimate the number of multis that represent split systems of one or more planets orbiting each component of a binary star system. We use the high reliability rate for multis to validate more than one dozen particularly interesting multi-planet systems herein. Hundreds of additional multi-planet systems are validated in a companion paper by Rowe et al. We note that few very short period (P < 1.6 days) planets orbit within multiple transiting planet systems and discuss possible reasons for their absence. There also appears to be a shortage of planets with periods exceeding a few months in multis.
The impact of Ada on software engineering

The term software engineering has traditionally been applied to extremely diverse activities, ranging from system programming to managing programmer teams. Ada appears destined to become the first widely used programming language designed to bring these diverse activities together in ways supported by both programmers and managers. Among many important aspects of the Ada language, the most important appear to be (1) its orientation to system construction using interchangeable building-block packages, and (2) strong standardization in the interest of program portability. These aspects should foster the emergence of a new kind of software component industry. A probable result will be an inversion of the traditional view of software as an added value for use on major hardware products. Instead, major machine-independent software systems will emerge, and hardware will be increasingly regarded as an added value.
Circle actions on simply connected 5-manifolds

Abstract The aim of this paper is to study compact 5-manifolds which admit fixed point free circle actions. The first result implies that the torsion in the second homology and the second Stiefel–Whitney class have to satisfy strong restrictions. We then show that for simply connected 5-manifolds these restrictions are necessary and sufficient.
Rhodium catalyzed enantioselective cyclization of substituted imidazoles via C–H bond activation

The enantioselective intramolecular alkylation of substituted imidazoles with enantiomeric excesses up to 98% has been accomplished by rhodium catalyzed C–H bond functionalization with (S,S′,R,R′)TangPhos as the chiral ligand.
Age differences in the effect of epidermal hydration on electrodermal activity.

The effect of epidermal hydration on skin potential and conductance measurements was investigated in young and old men. The condition of least hydration used a 0.5% KCl glycol electrolyte. Two conditions used a 0.5% aqueous KCl electrolyte differing in that the most hydrated site received a 15-min pretreatment of soaking in distilled water whereas the intermediate hydration site received no pretreatment. These hydration conditions were used in recording three channels of skin potential and three channels of skin conductance during three tasks: 1) tone presentations after rest, 2) simple reaction time, and 3) choice reaction time. There were no significant age differences in the effect of electrolyte on skin conductance level and response. There were age differences in the effect of electrolyte on skin potential level (SPL) and response (SPR). Young adult SPR was monotonically related to hydration with the largest response magnitude occurring with the least hydration. Electrolyte did not significantly affect SPR magnitude of the aged. For the young subjects, SPL was monotonically related to hydration with the most negative SPL occurring with the least hydration. For the aged subjects, the least negative SPL occurred in the condition of least hydration. We postulate that this reversal in the hydration/SPL relationship in old age reflects a reversal in the relative magnitudes of sweat gland and epidermal potentials: in old subjects the epidermal potential is greater than the sweat gland potential.
A New Synthesis of Alkyl-N,N-dinitramines by Direct Nitration of Isocyanates

Abstract A facile conversion of aliphatic isocyanates to N,N-dinitramines has been developed. An aliphatic isocyanate is treated with a mixture of nitronium fluoroborate and nitric acid in acetonitrile giving fair yields and simplifing the existing synthesis.
Analysis of orthogonality and of orbits in affine iterated function systems

We introduce a duality for affine iterated function systems (AIFS) which is naturally motivated by group duality in the context of traditional harmonic analysis. Our affine systems yield fractals defined by iteration of contractive affine mappings. We build a duality for such systems by scaling in two directions: fractals in the small by contractive iterations, and fractals in the large by recursion involving iteration of an expansive matrix. By a fractal in the small we mean a compact attractor X supporting Hutchinson’s canonical measure μ, and we ask when μ is a spectral measure, i.e., when the Hilbert space $${L^2( \mu)}$$ has an orthonormal basis (ONB) of exponentials $$\{{e_\lambda, | \lambda \in \Lambda}\}$$ . We further introduce a Fourier duality using a matched pair of such affine systems. Using next certain extreme cycles, and positive powers of the expansive matrix we build fractals in the large which are modeled on lacunary Fourier series and which serve as spectra for X. Our two main results offer simple geometric conditions allowing us to decide when the fractal in the large is a spectrum for X. Our results in turn are illustrated with concrete Sierpinski like fractals in dimensions 2 and 3.
Ricci flow on surfaces with cusps

We consider the normalized Ricci flow ∂tg = (ρ − R)g with initial condition a complete metric g0 on an open surface M where M is conformal to a punctured compact Riemann surface and g0 has ends which are asymptotic to hyperbolic cusps. We prove that when χ(M) < 0 and ρ < 0, the flow g(t) converges exponentially to the unique complete metric of constant Gauss curvature ρ/2 in the conformal class.
New non-ionic, highly water-soluble derivatives of C60 designed for biological compatibility

Abstract The most water-soluble (>240 mg C 60 mL −1 ) fullerene derivatives to date, the new malonodiserinolamide fullerenes C 60 [C(COSer) 2 ] n ( n =4, 5, 6, Ser=2-amino-1,3-propanediol), have been synthesized and characterized. The compounds were designed to provide maximum water solubility and biological compatibility. The facile synthesis is based on Bingel additions to C 60 and should be applicable to the solubilization of any prospective fullerene-based drug.
PREDATORY BEHAVIOR OF GOVERNMENTS: THE CASE OF MASS KILLING

In this paper we seek to answer the question: why do governments engage in mass killing? Tullock (1974) gives gain or avoidance of loss as the motive. We construct a three‐stage theoretic framework to explain the choice of a ruler of a country. The conditions that must be met for a mass killing regime to win over alternative regimes are derived. Using the COW project data over the period 1816–1997, we estimate two models: negative binomial regression of number of battle‐related deaths and a probit model for the choice of mass killing. The paper concludes with suggestions for data collections and further research.
The Marcinkiewicz multiplier condition for bilinear operators

This article is concerned with the question of whether Marcinkiewicz mul- tipliers onR 2n give rise to bilinear multipliers onR n R n . We show that this is not always the case. Moreover, we nd necessary and sucient conditions for such bilinear multipliers to be bounded. These conditions in particular imply that a slight logarithmic modica- tion of the Marcinkiewicz condition gives multipliers for which the corresponding bilinear operators are bounded on products of Lebesgue and Hardy spaces.
Links with no exceptional surgeries

We show that if a knot admits a prime, twist-reduced diagram with at least 4 twist regions and at least 6 crossings per twist region, then every non-trivial Dehn filling of that knot is hyperbolike. A similar statement holds for links. We prove this using two arguments, one geometric and one combinatorial. The combinatorial argument further implies that every link with at least 2 twist regions and at least 6 crossings per twist region is hyperbolic and gives a lower bound for the genus of a link.
Regiocontrol in the 1,3-dipolar cycloaddition reactions of mesoionic compounds with acetylenic dipolarophiles

Abstract The regioselectivity of 1,3-dipolar cycloaddition reactions between mesoionic compounds with singly-tethered substituents is examined. The results with propiolate dipolarophiles are compared with other singly and doubly-tethered examples according to a model using an asynchronous, concerted transition state. The isolation and reaction of a novel, nonaryl substituted mesoionic compound 7 is reported. A regiodirected synthesis starting with N-(2-thiazolinyl)proline gives a complementary dihydropyrroline compared with the reaction between N-formylproline and alkyl propiolates.