cssi/SciSciGPT-SciSciNet huggingface dataset:
Venus halo: Photometric evidence for ice in the Venus clouds

Abstract Photometric observations of Venus near the 1969 inferior conjunction indicate an anomalous brightening of about 0.07 magnitude at 158° phase angle. The width of the brightness maximum is about 3° and its peak is between 1.1 and 4.4 standard deviations, depending on color, from the expected background phase curve. These results tend to confirm earlier observations which marginally showed the same brightness maximum. This is precisely the behavior expected if the Venus cloudtops were to contain a small abundance (a few percent) of hexagonal water-ice crystals, producing a halo effect analogous to the common terrestrial 22° halo phenomenon. Proof of such a halo effect causing Venus' brightening cannot be considered as unequivocal, but the observations are certainly provocative enough to conclude there is strong evidence that some of the Venus cloudtops contain hexagonal ice.
A new evolutionary search strategy for global optimization of high-dimensional problems

Global optimization of high-dimensional problems in practical applications remains a major challenge to the research community of evolutionary computation. The weakness of randomization-based evolutionary algorithms in searching high-dimensional spaces is demonstrated in this paper. A new strategy, SP-UCI is developed to treat complexity caused by high dimensionalities. This strategy features a slope-based searching kernel and a scheme of maintaining the particle population's capability of searching over the full search space. Examinations of this strategy on a suite of sophisticated composition benchmark functions demonstrate that SP-UCI surpasses two popular algorithms, particle swarm optimizer (PSO) and differential evolution (DE), on high-dimensional problems. Experimental results also corroborate the argument that, in high-dimensional optimization, only problems with well-formative fitness landscapes are solvable, and slope-based schemes are preferable to randomization-based ones.
Variable-length tree-structured subvector quantization

It is demonstrated in this paper that the encoding complexity advantage of a variable-length tree-structured vector quantizer (VLTSVQ) can be enhanced by encoding low dimensional subvectors of a source vector instead of the source vector itself at the nodes of the tree structure without significantly sacrificing coding performance. The greedy tree growing algorithm for the design of such a vector quantizer codebook is outlined. Different ways of partitioning the source vector into its subvectors and several criteria of interest for selecting the appropriate subvector for making the encoding decision at each node are discussed. Techniques of tree pruning and resolution reduction are applied to obtain improved coding performance at the same low encoding complexity. Application of an orthonormal transformation such as KLT or subband transformation to the source and the implication of defining the subvectors from orthogonal subspaces are also discussed. Finally simulation results on still images and AR(1) source are presented to confirm our propositions.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Correction for ambiguous solutions in factor analysis using a penalized least squares objective

Factor analysis is a powerful tool used for the analysis of dynamic studies. One of the major drawbacks of factor analysis of dynamic structures (FADS) is that the solution is not mathematically unique when only nonnegativity constraints are used to determine factors and factor coefficients. In this paper, a method to correct for ambiguous FADS solutions has been developed. A nonambiguous solution (to within certain scaling factors) is obtained by constructing and minimizing a new objective function. The most common objective function consists of a least squares term that when minimized with nonnegativity constraints, forces agreement between the applied factor model and the measured data. In our method, this objective function is modified by adding a term that penalizes multiple components in the images of the factor coefficients. Due to nonuniqueness effects, these factor coefficients consist of more than one physiological component. The technique was tested on computer simulations, an experimental canine cardiac study using /sup 99m/Tc-teboroxime, and a patient planar /sup 99m/Tc-MAG/sub 3/ renal study. The results show that the technique works well in comparison to the truth in computer simulations and to region of interest (ROI) measurements in the experimental studies.
Elimination of singularities of smooth mappings of 4-manifolds into 3-manifolds

Abstract The simplest singularities of smooth mappings are fold singularities. We say that a mapping f is a fold mapping if every singular point of f is of the fold type. We prove1 1 that for a closed oriented 4-manifold M4 the following conditions are equivalent: (1) M4 admits a fold mapping into R 3 ; (2) for every orientable 3-manifold N3, every homotopy class of mappings of M4 into N3 contains a fold mapping; (3) there exists a cohomology class x∈H 2 (M 4 ; Z ) such that x⌣x is the first Pontrjagin class of M4. For a simply connected manifold M4, we show that M4 admits no fold mappings into N3 if and only if M4 is homotopy equivalent to C P 2 or C P 2 # C P 2 .
Rigidity of graded regular algebras

. We prove a graded version of Alev-Polo's rigidity theorem: the homogenization of the universal enveloping algebra of a semisimple Lie algebra and the Rees ring of the Weyl algebras A n (k) cannot be isomorphic to their fixed subring under any finite group action. We also show the same result for other classes of graded regular algebras including the Sklyanin algebras.
Engagement of the osteoclast integrin alpha v beta 3 by osteopontin stimulates phosphatidylinositol 3-hydroxyl kinase activity

Osteoclast adhesion via integrin alpha v beta 3 to the bone matrix protein osteopontin (OPN) results in stimulation of bone resorption. We characterized an immediate signaling event that takes place upon osteoclast interaction with OPN. OPN binding to alpha v beta 3 results in the rapid production of the phosphoinositides (PtdInsP), including phosphatidylinositol triphosphate (PtdIns 3,4,5P3). Stimulation of 3,4,5-PtdInsP3 production by OPN was produced by increased activity of PtdInsP 3-OH kinase, which was found in immunoprecipitates formed by antibodies to integrin alpha v beta 3. The association of PtdIns 3-OH kinase with integrin may have been through association with c-src. The latter was present in immunoprecipitates formed by the antibodies to integrin alpha v beta 3, and src kinase was activated by OPN. These findings demonstrate a mechanism for rapid generation of cell signals upon matrix protein binding to alpha v beta 3, which resembles the mechanisms used by tyrosine kinase growth factor receptors.
DISPLACEMENT OF SUGAR TRIFLATES WITH C-NUCLEOPHILES : D-GLUCOPYRANOSE AND D-RIBOFURANOSE CHAIN EXTENSION AND FUNCTIONALIZATION

Abstract Treatment of methyl 4-O-benzyl-2,3-di-O-methoxymethyl-6-O-1-6-O-trifluoromethanesulfonyl-α -D-glucopyranoside 1 or 3-O-benzyl-1,2-O-isopropylidene-5-O-trifluoromethenesulfonyl-α-D-ribofuranoside 2 with a variety of functionalized C-nucleophiles in THF/HMPA leads to the corresponding chain-extended sugars in very good to excellent yields.
An electromechanical vibration absorber

It is shown that by tuning the electrical circuit properly, the vibration amplitude of the original vibrating system to which the absorber is attached may be reduced significantly. This reduction is accompanied by large electrical oscillations in the resonant circuit, instead of the undesirable large amplitude mechanical oscillations in the conventional absorber. A mathematical analysis of the electromechancial vibration absorber is given, and some initial experimental results ar presented
Metastable superplumes and mantle compressibility

Seismically, the African superplume is known to have a sharp lateral transition in V_S and an interface between seismic anomalies with high relief. Such a structure is usually unstable in conventional thermo-chemical convection models. Using a compressible thermo-chemical convection model in which each material has a distinct equation of state, we find an expanded regime of metastable superplumes. In the preferred model, superplume material has a bulk modulus 6% higher and density 2.25% higher than ambient mantle. The inferred physical properties of the superplume are consistent with subducted oceanic crust, simultaneously satisfying seismological, geodynamical, mineralogical and geochemical constraints.
Leading, Following or Complementing in Economic Crisis: A Conceptual Model Illustrating Nonprofit Relationships with Public Schools

Public and nonprofit organizations, entwined in the delivery of public goods and services, are in the midst of challenging economic times. In these circumstances, sound collaborative leadership may help bridge budget and program service delivery shortfalls. In this paper, we examine the administrative dynamics of mutual reliance between two prominent public and nonprofit organizations: public schools and parent-teacher groups (PTGs). We conclude that the partnership is changing as a result of external, economic forces. In essence, we are seeing a threat-rigidity response. The economic crisis may be responsible for causing PTGs to narrow their range of activities away from broader strategic issues that can be addressed through their confrontation activities and advocacy mission towards a narrower focus on classroom activities that protect core school operations, namely instruction.
Efficacy of polyglycolic acid mesh sling in keeping the small bowel in the upper abdomen after abdominal surgery: a 12-month study in baboons.

The purpose of this study was to determine if a “sling” made of polyglycolic acid (PGA) would be a reliable method of preventing small bowel descent into the pelvis following abdominal surgery. Baboons were used, as they respond to infection and ambulate similarly to humans. Animals had the small bowel mobilized to the upper abdomen and had the PGA “sling” sewn into place. Documentation of small bowel position was evaluated by upper gastrointestinal series over the 12-month study. Small bowel descent into the pelvis was prevented by utilization of the PGA “sling.” Animals were sacrificed and autopsied, and sections of small bowel were taken. There was no evidence of mesh, obstruction, sepsis, fistulae, or herniation in animals at autopsy. Small bowel sections were considered normal histologically. Utilization of PGA sling appears to be a safe and reliable method of preventing small bowel descent into the pelvis after abdominal surgery.
Design and characteristics of the lightly doped drain-source (LDD) insulated gate field-effect transistor

The LDD structure, where narrow, self-aligned n-regions are introduced between the channel and the n+source-drain diffusions of an IGFET to spread the high field at the drain pinchoff region and thus reduce the maximum field intensity, is analyzed. The design is shown, including optimization of the n-dimensions and concentrations and the boron channel doping profile and an evaluation of the effect of the series resistance of the n-regions on device transconductance. Characteristics of experimental devices are presented and compared to those of conventional IGFET's. It is shown that significant improvements in breakdown voltages, hot-electron effects, and short-channel threshold effects can be achieved allowing operation at higher voltage, e.g., 8.5 versus 5 V, with shorter source-drain spacings, e.g., 1.2 versus 1.5 µm. Alternatively, a shorter channel length could be used for a given supply voltage. Performance projections are shown which predict 1.7 × basic device/circuit speed enhancement over conventional structures. Due to the higher voltages and higher frequency operation, the higher performance results in an increase in power which must be considered in a practical design.
Asymptotically Optimal Nonparametric Empirical Bayes Via Predictive Recursion

An empirical Bayes problem has an unknown prior to be estimated from data. The predictive recursion (PR) algorithm provides fast nonparametric estimation of mixing distributions and is ideally suited for empirical Bayes applications. This article presents a general notion of empirical Bayes asymptotic optimality, and it is shown that PR-based procedures satisfy this property under certain conditions. As an application, the problem of in-season prediction of baseball batting averages is considered. There the PR-based empirical Bayes rule performs well in terms of prediction error and ability to capture the distribution of the latent features.
Mesh quality effects on the accuracy of CFD solutions on unstructured meshes

The order of accuracy and error magnitude of node- and cell-centered schemes are examined on representative unstructured meshes and flowfield solutions for computational fluid dynamics. Specifically, we investigate the properties of inviscid and viscous flux discretizations for isotropic and highly stretched meshes using the Method of Manufactured Solutions. Grid quality effects are studied by randomly perturbing the base meshes and cataloguing the error convergence as a function of grid size. For isotropic grids, node-centered approaches produce less error than cell-centered approaches. Moreover, a corrected node-centered scheme is shown to maintain third order accuracy for the inviscid terms on arbitrary triangular meshes. In contrast, for stretched meshes, cell-centered schemes are favored, with cell-centered prismatic approaches in particular showing the lowest levels of error. In three dimensions, simple flux integrations on non-planar control volume faces lead to first-order solution errors, while second-order accuracy is recovered by triangulation of the non-planar faces.
Metachronous Bilateral Wilms' Tumor. The Importance of Time Interval to the Development of a Second Tumor

BACKGROUND Information regarding survival and prognostic factors in children with metachronous bilateral Wilms' tumor is limited. METHODS A literature search of English language articles from 1950-1996 was performed. A total of 108 of 123 children with metachronous bilateral Wilms' tumor from 30 studies were evaluable for analysis. The children were classified according to the time interval to the development of a contralateral Wilms' tumor (< 18 months vs. ≥ 18 months). RESULTS Kaplan-Meier analysis rates of overall survival for metachronous bilateral Wilms' tumor were 49.1% and 47.2% at 5 and 10 years, respectively. The median time interval to the development of a second tumor was 23.1 months. Of 106 children, 102 (96.2%) had a metachronous presentation of Wilms' tumor by 5 years. In children ages < 2 years and children ages 2-5 years, 95.2% and 93.9%, respectively, of contralateral tumors appeared within 60 months. For children ages ≥ 5 years, all contralateral kidney tumors appeared by 54 months. Analysis of overall survival of patients with a time interval of < 18 months and ≥ 18 months showed a 10-year survival of 39.6% and 55.2%, respectively (P = 0.024, log rank test). CONCLUSIONS Children with a metachronous bilateral Wilms' tumor who developed a contralateral tumor ≥ 18 months from the initial diagnosis of Wilms' tumor had a better overall survival than children with a time interval of 5 years after initial diagnosis of Wilms' tumor may not be necessary because > 95% of children had a time interval to the development of a second tumor of ≤ 60 months. Cancer 1998;82:415-20. © 1998 American Cancer Society.
Goal-Directed Program Transformation

Program development often proceeds by transforming simple, clear programs into complex, involuted, but more efficient ones. This paper examines ways this process can be rendered more systematic. We show how analysis of program performance, partial evaluation of functions, and abstraction of recursive function definitions from recurring subgoals can be combined to yield many global transformations in a methodical fashion. Examples are drawn from compiler optimization, list processing, very high-evel languages, and APL execution.
Diastereoselective nickel-catalyzed reductive couplings of aminoaldehydes and alkynylsilanes: application to the synthesis of d-erythro-sphingosine

A strategy for the nickel-catalyzed reductive coupling of α-aminoaldehydes with silyl alkynes has been developed. The process proceeds with exceptional regiocontrol and diastereoselectivity. A variety of protected serinal derivatives were examined, and Garner aldehyde afforded the highest chemical yields of an easily deprotected coupling product. Use of a C-15 alkyne allowed a direct and efficient synthesis of D-erythro-sphingosine. With this silyl alkyne of interest, coupling reactions were most efficient when trace water was employed with THF as solvent. Using this procedure, D-erythro-sphingosine was prepared by a short sequence, wherein the alkene stereochemistry, C-3 stereocenter, and the C-3-C-4 carbon-carbon bond were all efficiently installed by the key nickel-catalyzed coupling process.
Arrow's equivalency theorem in a model with neoclassical firms

In this paper we consider a two-period general equilibrium model with uncertainty and real assets as financial instruments. The novelty of the analysis is that real assets are the stocks of neoclassical firms, so that both returns and yields depend on anticipated spot goods prices (and, of course, the yield matrix may change rank with prices). Assuming that financial markets are potentially complete, we establish generic existence of financial equilibrium and prove that there exists a dense set of economies such that financial equilibria are efficient.
Limits of elliptic hypergeometric integrals

In Ann. Math., to appear, 2008, the author proved a number of multivariate elliptic hypergeometric integrals. The purpose of the present note is to explore more carefully the various limiting cases (hyperbolic, trigonometric, rational, and classical) that exist. In particular, we show (using some new estimates of generalized gamma functions) that the hyperbolic integrals (previously treated as purely formal limits) are indeed limiting cases. We also obtain a number of new trigonometric (q-hypergeometric) integral identities as limits from the elliptic level.
Effective Tunneling Density of States in Superconductors

Results of a theoretical determination of the tunneling characteristic, that agree well with structure observed in the I-V characteristic of superconducting metals, are presented. Experimental and theoretical curves for the density of states show good agreement. (D.C.W.)
Spin orientation of holes in quantum wells

This paper reviews the spin orientation of spin-3/2 holes in quantum wells. We discuss the Zeeman and Rashba spin splitting in hole systems that are qualitatively different from their counterparts in electron systems. We show how a systematic understanding of the unusual spin-dependent phenomena in hole systems can be gained using a multipole expansion of the spin density matrix. As an example we discuss spin precession in hole systems that can give rise to an alternating spin polarization. Finally, we discuss the qualitatively different regimes of hole spin polarization decay in clean and dirty samples.
A user's guide to nonlinear optimization algorithms

The purpose of this paper is to provide a user's introduction to the basic ideas currently favored in nonlinear optimization routines by numerical analysts. The primary focus will be on the unconstrained problem because the main ideas are much more settled. Although this is not a paper about nonlinear least squares, the rich structure of this important practical problem makes it a convenient example to use to illustrate the ideas we will discuss. We will make most use of this example in the first three sections which deal with the helpful concept of a local modeling technique and the attendant local convergence analysis. Stress will be put on ways used to improve a poor initial solution estimate since this is one of the keys to choosing the most suitable routine for a particular application. This material is covered in the rather long Section 4. The discussion of the constrained problem in Section 5 will be a brief outline of the current issues involved in deciding what algorithms to implement. Section 6 is devoted to some concluding remarks including some sparse comments on large problems.
Preparation of Dried Latex Films

Abstract Various technical applications of latex call for the formation of a latex film and its drying by evaporation of the water in which the rubber is dispersed. The same problem is encountered also in the preparation of dried latex films, both uncompounded and compounded, for film testing for tensile, elongation, and other properties. Very frequently the preparation of such films is complicated by the development of surface cracks and ridges in the drying films, which mar the appearance of the films, detract from their strength, and make testing difficult and uncertain. These imperfections in the films generally arise from the formation of impervious surface skins on the drying latex. Such impervious skins lead to shrinkage and subsequent cracking of the films on the one hand, and to bubble formation on the other. The result is that the preparation of dried latex films by this method becomes a very slow process, which yields as a rule films of inferior appearance and quality. It was found in this labo...
Open Systems Viewed Through Their Conservative Extensions

A typical linear open system is often defined as a component of a larger conservative one. For instance, a dielectric medium, defined by its frequency dependent electric permittivity and magnetic permeability is a part of a conservative system which includes the matter with all its atomic complexity. A finite slab of a lattice array of coupled oscillators modelling a solid is another example. Assuming that such an open system is all one wants to observe, we ask how big a part of the original conservative system (possibly very complex) is relevant to the observations, or, in other words, how big a part of it is coupled to the open system? We study here the structure of the system coupling and its coupled and decoupled components, showing, in particular, that it is only the system’s unique minimal extension that is relevant to its dynamics, and this extension often is tiny part of the original conservative system. We also give a scenario explaining why certain degrees of freedom of a solid do not contribute to its specific heat.
Acoustic and turbulence influences on stall hysteresis

P AST testing of airfoils at low Reynolds number has revealed stall hysteresis to be a characteristic of airfoil aerodynamic behavior at Reynolds numbers between about 75,000 and 500,000. This important phenomenon, has been seen by some researchers but not by others, and the extent of the loop has varied in results from different investigators. The purpose of this study was to investigate the extent to which wind-tunnel, flow turbulence and acoustic disturances may alter the nature of the flow over an airfoil at low Reynolds number and the character of the stall hysteresis loop. The results indicate that such disturbances may have dramatic effects on stall hysteresis and may be responsible for the lack of stall hysteresis data in many past investigations.
MAGNETOHYDRODYNAMIC SIMULATIONS OF THE ATMOSPHERE OF HD 209458b

We present the first three-dimensional magnetohydrodynamic (MHD) simulations of the atmosphere of HD?209458b which self-consistently include reduction of winds due to the Lorentz force and Ohmic heating. We find overall wind structures similar to that seen in previous models of hot Jupiter atmospheres, with strong equatorial jets and meridional flows poleward near the day side and equatorward near the night side. Inclusion of magnetic fields slows those winds and leads to Ohmic dissipation. We find wind slowing ranging from 10%-40% for reasonable field strengths. We find Ohmic dissipation rates ~1017?W at 100 bar, orders of magnitude too small to explain the inflated radius of this planet. Faster wind speeds, not achievable in these anelastic calculations, may be able to increase this value somewhat, but likely will not be able to close the gap necessary to explain the inflated radius. We demonstrate that the discrepancy between the simulations presented here and previous models is due to inadequate treatment of magnetic field geometry and evolution. Induced poloidal fields become much larger than those imposed, highlighting the need for a self-consistent MHD treatment of these hot atmospheres.
Morphology and processing of aligned carbon nanotube carbon matrix nanocomposites

Intrinsic and scale-dependent properties of carbon nanotubes (CNTs) have led aligned CNT architectures to emerge as promising candidates for next-generation multifunctional applications. Enhanced operating regimes motivate the study of CNT-based aligned nanofiber carbon matrix nanocomposites (CNT A-CMNCs). However, in order to tailor the material properties of CNT A-CMNCs, porosity control of the carbon matrix is required. Such control is usually achieved via multiple liquid precursor infusions and pyrolyzations. Here we report a model that allows the quantitative prediction of the CNT A-CMNC density and matrix porosity as a function of number of processing steps. The experimental results indicate that the matrix porosity of A-CMNCs comprised of ∼1% aligned CNTs decreased from ∼61% to ∼55% after a second polymer infusion and pyrolyzation. The model predicts that diminishing returns for porosity reduction will occur after 4 processing steps (matrix porosity of ∼51%), and that >10 processing steps are required for matrix porosity <50%. Using this model, prediction of the processing necessary for the fabrication of liquid precursor derived A-CMNC architectures, with possible application to other nanowire/nanofiber systems, is enabled for a variety of high value applications.
Pulmonary Alveolar Proteinosis

SINCE the report, by Rosen, Castleman and Liebow,1 of the histologic entity of pulmonary alveolar proteinosis a variety of syndromes have been described. The clinical presentations have ranged from an asymptomatic pulmonary infiltrate, incidentally discovered,2 to an unexplained recurrent fever of one and a half years' duration.3 The roentgenograms of the chest in most reported cases have shown a perihilar, granular infiltrate radiating to the lower fields of the lung — the area of the lung with the greatest radiodensity. In some patients, however, unilateral infiltrations, patchy infiltrations and even cavitary lesions2 have been described. The nonspecific clinical and x-ray . . .
Carbohydrate Mimetics: A New Strategy for Tackling the Problem of Carbohydrate‐Mediated Biological Recognition

Useful strategies for the design of molecules to mimic carbohydrates have been developed over the past few years. Mimics of the target may contain new functional groups, a new scaffold, or both (in the schematic representation the natural ligand is shown on the left and the modified version on the right). Many examples of successful carbohydrate mimetics that interfere with sugar–protein and sugar–nucleic acid interactions are known.
Direct Measurements of Electron Density, Temperature and Ion Composition in an Equatorial Spread-F Ionosphere.

Abstract Ionospheric plasma irregularities have been studied on each of two rockets launched into significantly different conditions of equatorial spread-F. In the first operation (into a spread-F decay phase) a number of major depletions ( Δ e N e 0 ≲ 90% ) were distributed throughout the F-region from its bottomside gradient centered near 260 km, through the F-peak, to a topside altitude of 500 km. In a second operation (launched into a mid-phase development of spread-F) irregularities were observed only on the bottomside gradient, with no depletions in or above the F-peak. In both cases O+ was the dominant F-region ion down to the very bottom of the F-ledge. At altitudes below the ledge, molecular ions dominated with a scale height approaching infinity. The most significant ion chemical results were collected on the first launch where none of the depletions showed evidence of typical bottomside source ions (NO+, O2+ or meteorics). Instead, the [N + ] [O + ] ratio proved to be the appropriate signature for the depletion's bottomside source domain. The ion composition results also impact on speculations that neutral atmospheric turbulence is a triggering mechanism for bottomside irregularities. Indeed, the results of the first launch point to a uniform neutral atmospheric profile in the presence of extremely irregular bottomside ion distributions, a result which tends to negate the possible role of atmospheric turbulence.
Representation of magnetic fields in space

Several methods by which a magnetic field in space can be represented are reviewed with particular attention to problems of the observed geomagnetic field. Time dependence is assumed to be negligible, and five main classes of representation are described by vector potential, scalar potential, orthogonal vectors, Euler potentials, and expanded magnetic field.
Polymer-Supported Copper(I) Catalysts for the Experimentally Simplified Azide–Alkyne Cycloaddition

Tris-(benzyltriazolylmethyl)amine (TBTA), a widely used ligand for the copper-catalyzed azide-alkyne cycloaddition, has been immobilized on a TentaGel resin. Once loaded with copper(I), the resulting air-stable complex acts as an efficient catalyst for the azide-alkyne cycloaddition reaction and prevents contamination of products by copper salts. The immobilized TBTA ligand should find immediate use in the parallel synthesis of compounds for direct screening.
Mixed-norm H 2 /H ∞ regulation and estimation: the discrete-time case

Abstract A discrete-time H2 static output feedback design problem involving a constraint on H∞ disturbance attenuation is addressed and state space formulae are derived. The dual problem of discrete-time dynamic estimation with an H∞ error bound is also addressed. These results are analogous to results obtained previously for the continuous-time problem.
Effects of the electroweak symmetry breaking sector in rare B and K decays

Abstract The effects of the electroweak symmetry breaking sector in rare B and K decays are considered in the presence of new strong dynamics at a large energy scale. In the context of the low energy effective lagrangian of the symmetry breaking sector, we focus on the contributions that are not constrained by bounds on oblique corrections or anomalous triple gauge boson vertices. We find that these have very little effect in b → sγ , but potentially large contributions appear in b → s l + l − and b → sν ν as well as in b → sg processes. Deviations from the standard model in rare K decays such as K + → π + ν ν and K L → π 0 ν ν are shown to be correlated with tthe ones in the B modes. The distinct resulting pattern of deviations from the standard model in rare decays is a characteristic feature of a strongly interacting electroweak symmetry breaking sector.
Steady and Self-Similar Solutions of Non-Strictly Hyperbolic Systems of Conservation Laws

We consider solutions of two-dimensional m × m systems hyperbolic conservation laws that are constant in time and along rays starting at the origin. The solutions are assumed to be small L ∞ perturbations of a constant state and entropy admissible, and the system is assumed to be non-strictly hyperbolic with eigenvalues of constant multiplicity. We show that such a solution, initially assumed bounded, must be a special function of bounded variation, and we determine the possible configuration of waves. As a corollary, we extend some regularity and uniqueness results for some one-dimensional Riemann problems.
The Association of Intra-Abdominal Infection and Abdominal Wound Dehiscence

Concurrent infection is a risk factor for abdominal wound dehiscence. We reviewed our experience with fascial dehiscence to determine the incidence and to identify prognostic factors for associated intra-abdominal infection. Over a 7-year period, 107 patients with abdominal wound dehiscence were identified. Seventeen were managed nonoperatively, and 90 underwent exploratory laparotomy, 43 of whom had no intra-abdominal pathology and 47 of whom had intra-abdominal infections. Demographic factors, comorbid diseases, and potential indicators of systemic infection did not distinguish patients with intra-abdominal infection from those without. Patients with an intra-abdominal infection were more likely to have undergone an emergency operation (74% vs 48%; P < 0.02), an operation on the colon (55% vs 25%; P < 0.005), or an operation with a higher wound classification (P < 0.02). Mortality was higher in patients with intra-abdominal infection than in those without (44% vs 20%; P < 0.02). Wound dehiscence after emergent operations, and operations with a higher wound classification, especially those involving the colon, should raise concern for intra-abdominal infection. Thorough abdominal exploration should be performed at the time of dehiscence repair. Before nonoperative management is chosen, intra-abdominal infection should be excluded.
New longitudinal handling qualities data - Carrier approach

The results of an aircraft flying qualities research program sponsored by the Naval Air Systems Command are presented. Navy test pilot evaluations in the form of pilot ratings and specific comments of several longitudinal handling characteristics were obtained for a simulated carrier landing task. The investigation made use of a variable stability aircraft which accurately simulated the longitudinal short-period response characteristics and the effects of atmospheric turbulence. The flying qualities associated with variations in short-period frequency (usp range of 0.6-2.0), lift curve slope (La/V range of 0.6-1.35), and the use of direct lift control are presented. The data are compared with similar data obtained from flight and ground simulator tests. All configurations tested were found to be acceptable for the daylight visual carrier approach task, and only minor differences in the flying qualities of the configurations were evident.
Application of a colored noise Kalman filter to a radio-guided ascent mission

Abstract : A set of general sequential filter equations is derived for nonlinear system dynamics and a nonlinear observation model, but is obtained with the assumption of a linear estimator. These equations, which are based upon previously developed formulas, include the colored measurement noise statistics and the statistics of nonestimated model parameter errors. Several simulations made with this filter are compared with the simulation results of an estimation procedure constructed with the utilization of the standard white noise assumptions. The difference between the white noise filter results and the colored noise filter results is found to be minimal. Instability occurred when the statistics of the effective exhaust velocity in the acceleration model were not properly accounted for.
String defects in condensed-matter systems as optical fibers

We analyze the core structure of string defects in transparent condensed-matter systems and argue that in certain cases the variation of the refractive index near the core may be such that it can lead to total internal reflection of light traveling along the string core. Such strings will thus behave as optical fibers. We consider several cases, such as superfluid helium and liquid crystals, where this possibility may be realized.
Higher Mycophenolate Dose Requirements in Children Undergoing Hematopoietic Cell Transplant (HCT)

Little is known about dosing of mycophenolate mofetil in pediatric hematopoietic cell transplant recipients; therefore, dosing strategies using other settings have been extended to this population. The authors studied pharmacokinetics in 19 children (median 17 months) undergoing myeloablative hematopoietic cell transplant and receiving prophylactic mycophenolate and cyclosporine. All subjects except 2 received mycophenolate 15 mg/kg intravenously every 8 hours. The median (range) total mycophenolic acid area under the concentration-time curve (AUC)(0-8) was 12.6 mcg.h/mL (4.9-49.2), and unbound mycophenolic acid AUC(0-8) was 0.274 mcg.h/mL (0.037-1.4). Total and unbound mycophenolic acid trough concentrations were 0.27 (0.03-2.9) and 0.005 (0-0.034) mcg/mL, respectively. Mycophenolic acid trough concentrations were not good surrogates for overall exposure (AUC(0-8)), r(2) < or = 0.55. Mycophenolate dose requirements are higher in pediatric hematopoietic cell transplant recipients relative to pediatric organ transplant recipients. Children undergoing hematopoietic cell transplant should receive a mycophenolate mofetil dose of at least 15 mg/kg intravenously every 8 hours when used in combination with cyclosporine to achieve systemic concentrations near those proposed to be therapeutic in the adult hematopoietic cell transplant population.
Robust Sampled Data Eigenstructure Assignment Using the Delta Operator

Eigenstructure assignment is considered for a linear time-invariant plant that is represented by the so-called unified delta model, which is valid both for continuous time and sampled data operation of the plant. We show that the eigenvectors of the delta model are identical to the eigenvectors of the continuous time plant and an expression is derived for the eigenstructure assignment feedback gain matrix for the delta model. We extend a sufficient condition for robust stability to the delta model of the plant. A robust sampled data design is computed for the Extended Medium Range Air-to-Air Technology missile by minimizing the integral of the roll rate with constraints on selected eigenvalues, actuator deflection rates, and the sufficient condition for robust stability. The robust design exhibits a significantly improved sideslip gust response as compared to an orthogonal projection eigenstructure assignment design.
A complete algorithm for designing passive fences to orient parts

Reviews Peshkin and Sanderson (1988) who showed that parts can be aligned as they move on a conveyor belt against a passive sequence of fences. Describes the first complete algorithm to design such sequences for a given convex polygonal part. The algorithm is complete in the sense that it is guaranteed to find a design if one exists and to terminate with a negative report otherwise. Based on an exact breadth‐first search of the design space, the algorithm is also guaranteed to find the design requiring the fewest fences. Describes the algorithm and compares results with those previously reported. Conjectures that a fence design exists to orient any convex polygonal part defined by a sequence of rational vertices.
Banjo timbre from string stretching and frequency modulation

The geometry of a floating bridge on a drumhead soundboard produces string stretching that is first order in the amplitude of the bridge motion. This stretching modulates the string tension and consequently modulates string frequencies at acoustic frequencies. Early work in electronic sound synthesis identified such modulation as a source of bell-like and metallic timbre. And increasing string stretching by adjusting banjo string-tailpiece-head geometry enhances characteristic banjo tone. Hence, this mechanism is likely a significant source of the ring, ping, clang, and plunk common to the family of instruments that share floating-bridge/drumhead construction.
Continuum methods in lattice perturbation theory

We show how methods of continuum perturbation theory can be used to simplify perturbative lattice calculations. We use the technique of asymptotic expansions to expand lattice loop integrals around the continuum limit. After the expansion, all nontrivial dependence on momenta and masses is encoded in continuum loop integrals and the only genuine lattice integrals left are tadpole integrals. Using integration-by-parts relations all of these can be expressed in terms of a small number of master integrals. Four master integrals are needed for bosonic one loop integrals, sixteen in QCD with Wilson or staggered fermions.
Spatio-Temporal Scaling of Turbulent Photospheric Line-of-Sight Magnetic Field in Active Region NOAA 11158

We studied the structure and dynamics of the turbulent photospheric magnetic field in active region NOAA 11158 by characterizing spatial and temporal scaling properties of the line-of-sight (LOS) component. Using high-resolution high-cadence LOS magnetograms from SDO/HMI, we measured the power-law exponents α and β that describe Fourier power spectra in wavenumber (k) and frequency (f) domains, and we investigated their evolution during the passage of the active region through the field of view of HMI. The flaring active region NOAA 11158 produces a one-dimensional spatial power spectral density that approximately follows a k −2 power law – a spectrum that suggests parallel MHD fluctuations in an anisotropic turbulent medium. In addition, we found that the values of α capture systematically change in the configuration of the LOS photospheric magnetic field during flaring activity in the corona. Position-dependent values of the temporal scaling exponent β showed that, on an average, the core of the active region scales with β>3 surrounded by a diffusive region with an approximately f −2-type spectrum. Our results indicate that only about 1 – 3 % of the studied LOS photospheric magnetic flux displays β≈α, implying that Taylor’s hypothesis of frozen-in-flow turbulence is typically invalid for this scalar field in the presence of turbulent photospheric flows. In consequence, both spatial and temporal variations of the plasma and magnetic field must be included in a complete description of the turbulent evolution of active regions.
Evaluation of fatigue damage using nonlinear guided waves

This research develops an experimental procedure for characterizing fatigue damage in metallic plates using nonlinear guided waves. The work first considers the propagation of nonlinear waves in a dispersive medium and determines the theoretical and practical considerations for the generation of higher order harmonics in guided waves. By using results from the nonlinear optics literature, it is possible to demonstrate that both phase and group velocity matching are essential for the practical generation of nonlinear guided elastic waves. Next, the normalized acoustic nonlinearity of low cycle fatigue damaged aluminum specimens is measured with Lamb waves. A pair of wedge transducers is used to generate and detect the fundamental and second harmonic Lamb waves. The results show that the normalized acoustic nonlinearity measured with Lamb waves is directly related to fatigue damage in a fashion that is similar to the behavior of longitudinal and Rayleigh waves. This normalized acoustic nonlinearity is then compared with the measured cumulative plastic strain to confirm that these two parameters are related, and to reinforce the notion that Lamb waves can be used to quantitatively assess plasticity driven fatigue damage using established higher harmonic generation techniques.
General relativistic simulations of black-hole-neutron-star mergers: Effects of black-hole spin

Black-hole-neutron-star (BHNS) binary mergers are candidate engines for generating both short-hard gamma-ray bursts and detectable gravitational waves. Using our most recent conformal thin-sandwich BHNS initial data and our fully general relativistic hydrodynamics code, which is now adaptive mesh refinement capable, we are able to efficiently and accurately simulate these binaries from large separations through inspiral, merger, and ringdown. We evolve the metric using the Baumgarte-Shapiro-Shibata-Nakamura formulation with the standard moving puncture gauge conditions, and handle the hydrodynamics with a high-resolution shock-capturing scheme. We explore the effects of BH spin (aligned and antialigned with the orbital angular momentum) by evolving three sets of initial data with BH:NS mass ratio q=3: the data sets are nearly identical, except the BH spin is varied between a/M{sub BH}=-0.5 (antialigned), 0.0, and 0.75. The number of orbits before merger increases with a/M{sub BH}, as expected. We also study the nonspinning BH case in more detail, varying q between 1, 3, and 5. We calculate gravitational waveforms for the cases we simulate and compare them to binary black-hole waveforms. Only a small disk (<0.01M{sub {center_dot}}) forms for the antialigned spin case (a/M{sub BH}=-0.5) and for the most extreme-mass-ratio case (q=5). By contrast, a massive (M{sub disk}{approx_equal}0.2M{submore » {center_dot}}) hot disk forms in the rapidly spinning (a/M{sub BH}=0.75) aligned BH case. Such a disk could drive a short-hard gamma-ray burst, possibly by, e.g., producing a copious flux of neutrino-antineutrino pairs.« less
Finite element modeling of 3D turning of titanium

The finite element modeling and experimental validation of 3D turning of grade two commercially pure titanium are presented. The Third Wave AdvantEdge machining simulation software is applied for the finite element modeling. Machining experiments are conducted. The measured cutting forces and chip thickness are compared to finite element modeling results with good agreement. The effects of cutting speed, a limiting factor for productivity in titanium machining, depth of cut, and tool cutting edge radius on the peak tool temperature are investigated. This study explores the use of 3D finite element modeling to study the chip curl. Reasonable agreement is observed under turning with small depth of cut. The chip segmentation with shear band formation during the Ti machining process is investigated. The spacing between shear bands in the Ti chip is comparable with experimental measurements. Results of this research help to guide the design of new cutting tool materials and coatings and the studies of chip formation to further advance the productivity of titanium machining.
N-(Benzoyloxy)amines: an investigation of their thermal stability, synthesis, and incorporation into novel peptide constructs

Abstract A series of N-benzoyloxyamines were pyrolyzed and their decomposition temperatures correlated well with the amine architecture's ability to stabilize a N-centered radical. A variety of amine substrates were treated with a biphasic mixture of benzoyl peroxide (BPO), CH2Cl2 and an aqueous carbonate buffer (at pH 10.5). Primary and secondary amines were successfully N-benzoyloxylated in good yield. Tertiary amines and BPO gave low yields of the corresponding N-oxide and complex product mixtures, presumably via radical decomposition. Electron deficient amines (such as fluorinated aliphatic amines, α-aminoacids, α-aminoesters, and α-aminoamides) were not N-benzoyloxylated under these conditions. Instead, N-benzoylation was observed with the fluorinated amines and the reaction was sensitive to temperature and the pH of the aqueous medium. A one-pot-two-step synthesis of Nα-FMOC- l -Leu-Nβ-(benzoyloxy)-β-alanine ethyl ester, a peptide containing both an α- and a novel β-amino acid framework, was also developed.
Fairness in Agent Based Simulation Frameworks

An agent based simulation engine should be able to provide a fair playing field for its agents. This paper analyzes fairness in the sequencing of agent thread execution within a Java framework that implements a multithreaded, time stepping, agent based simulation engine. The results illustrate why a multithreaded agent based simulation framework using the Java Virtual Machine for concurrency must supplement standard Java thread scheduling with techniques that enable fairness in agent execution order. The "uniform specific notification" pattern is introduced as one technique for producing fairer, uniformly distributed order for initial execution of Java agent threads at each simulation step.
Simulation of Total Equilibrium Shock-Layer Radiation for Three Typical Entry Body Shapes

Total equilibrium shock layer radiation data for Martian entry body shapes at various angles of attack extrapolated to trajectory condition