cssi/SciSciGPT-SciSciNet huggingface dataset:
Voting fusion adaptation for landmine detection

This paper presents a voting fusion application for use with a remotely controlled multisensor vehicle platform for antitank landmine detection. Data from three landmine detection sensors mounted at the front of the vehicle enhance the probability of detection and, when combined via data fusion, limit the false alarm density to practical levels. The performance of the voting fusion scheme presented in this paper is contrasted with a heuristic data fusion approach developed by General Dynamics Canada.
A permutation approach to validation

We give a permutation approach to validation (estimation of out‐sample error). One typical use of validation is model selection. We establish the legitimacy of the proposed permutation complexity by proving a uniform bound on the out‐sample error, similar to a Vapnik‐Chervonenkis (VC)‐style bound. We extensively demonstrate this approach experimentally on synthetic data, standard data sets from the UCI‐repository, and a novel diffusion data set. The out‐of‐sample error estimates are comparable to cross validation (CV); yet, the method is more efficient and robust, being less susceptible to overfitting during model selection. Copyright © 2010 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 3: 361‐380 2010 © 2010 Wiley Periodicals, Inc. A preliminary version of this paper appears in the Siam Data Mining Conference, 2010.
Distributed feedback laser biosensor incorporating a titanium dioxide nanorod surface

A 6.6× enhancement in surface sensitivity of DFB laser biosensors is demonstrated by a device incorporating a porous titanium dioxide nanorod layer on the sensor surface, while a Q-factor of over 25, 000 is maintained.
The performance impact of traffic patterns on routing protocols in mobile ad hoc networks

As mobile ad hoc network (MANET) systems research has matured and several testbeds have been built to study MANETs, research has focused on developing new MANET applications such as collaborative games, collaborative computing, messaging systems, distributed security schemes, MANET middleware, peer-to-peer file sharing systems, voting systems, resource management and discovery, vehicular computing and collaborative education systems. The growing set of diverse applications developed for MANETs pose far more complex traffic patterns than the simple one-to-one traffic pattern, and hence the one-to-one traffic pattern widely used in previous protocol studies has become inadequate in reflecting the relative performance of these protocols when deployed to support these emerging applications. As a first step towards effectively supporting newly developed and future diverse MANET applications, this paper studies the performance impact of diverse traffic patterns on routing protocols in MANETs. Specifically, we propose a new communication model that extends the previous communication model to include a more general traffic pattern that varies the number of connections per source node. We study the performance impact of traffic patterns on various routing protocols via detailed simulations of an ad hoc network of 112 mobile nodes. Our simulation results show that many of the conclusions drawn in previous protocol comparison studies no longer hold under the new traffic patterns. These results motivate the need for performance evaluation of ad hoc networks to not only include rich and diverse mobility models as has been done in the past but also include diverse traffic patterns that stress a wide set of protocol design issues.
Syntheses and Metal Ion Complexation of Novel 8-Hydroxyquinoline-Containing Diaza-18-Crown-6 Ligands and Analogues

Ten new 8-hydroxyquinoline-containing diaza-18-crown-6 ligands and analogues were synthesized via a one-pot or stepwise Mannich reaction, reductive amination, or by reacting diaza-18-crown-6 with 5,7-dichloro-2-iodomethyl-8-quinolinol in the presence of N,N-diisopropylethylamine. The Mannich reaction of N,N‘-bis(methoxymethyl)diaza-18-crown-6 with 4-chloro-2-(1H-pyrazol-3-yl)phenol gave the NCH2N-linked bis(3-(5-chloro-2-hydroxy)pyrazol-1-ylmethyl)-substituted diazacrown ether (14) in a 98% yield. The reaction of bis(N,N‘-methoxymethyldiaza)-18-crown-6 with 2.2 equiv of 10-hydroxybenzoquinoline gave only the monosubstituted diazacrown ether ligand (8). Interaction of some of the ligands with various metal ions was evaluated by a calorimetric titration technique at 25 °C in MeOH. Bis(8-hydroxyquinoline-2-ylmethyl)-substituted ligand 13 forms a very strong complex with Ba2+ (log K = 11.6 in MeOH) and is highly selective for Ba2+ over Na+, K+, Zn2+, and Cu2+ (selectivity factor > 106). The 1H NMR spectral st...
High-Toughness B4C-AlB12 Composites Prepared by Al Infiltration

Abstract An infiltration technique for fabricating B 4 C-matrix composites has been investigated. B 4 C-Al composites prepared by infiltration are well densified and have shrinkage of about 0.15%, but the fracture toughness is low. The addition of AlB 12 has a strong effect in increasing the toughness of B 4 C-matrix composites. The high fracture toughness of B 4 C-AlB 12 -Al composites is caused by residual Al and by the behaviour of metastable stress-induced phase transition of AlB 12 fromβ-phase to α-phase. The highest hardness (1870 kg/mm 2 ) and flexural strength (457 MPa) are obtained in B 4 C-matrix sample with 8% AlB 12 .
NEURODEVELOPMENTAL FUNCTIONING OF GOOD AND POOR READERS IN URBAN SCHOOLS

This study investigated specific aspects of neurodevelopmental functioning in good and poor readers entering second grade, and followed their neurodevelopmental course and reading progress over a three year period. Poor readers at age seven performed significantly worse than good readers on assessment of gross and fine motor coordination and corticosensory functioning. Furthermore, the presence of soft signs at age seven was significantly predictive of reading achievement at age ten. Group differences in neurodevelopmental functioning disappeared by age ten and the presence of soft signs at ages eight and nine no longer was predictive of reading achievement. These findings have implications for pediatricians, educators and researchers exploring brain/behavior relationships.
Mammalian Alkaloids: O‐methylation of (S)‐ and (R)‐dideoxynorlaudanosoline‐1‐carboxylic acid by catechol O‐methyltransferase and identification of a yellow pigment obtained at physiological pH

O-Methylation of optically active 3′,4′-dideoxynorlaudanosoline-l-carboxylic acids 1 with O-methyltransferase in vitro afforded almost exclusively the 7-O-methylated acids 3. A similar result was obtained with the yellow quinonemethide 4A obtained from 1 at neutral or slightly alkaline pH by oxidative decarboxylation and affording the 3,4-dihydroisoquinoline 15 on methylation with catechol O-methyltransferase (COMT). The structure of quinonemethide 4A was determined on the basis of spectral data, by its conversion into isoquinolines of established structure, and by synthesis. Quinonemethide 4A was found to be a weak inhibitor of monoamine oxidase A (MAO A) but not a substrate. Nonenzymatic oxidative decarboxylation of dopamine-derived tetrahydroisoquinoline-l-carboxylic acids to quinonemethides may be a major factor in biochemical experimentation and should be considered in the interpretation of data.
Ubiquitous Variability of X-Ray-absorbing Column Densities in Seyfert 2 Galaxies

We present a study of the variations in the absorbing column density of 25 X-ray-defined Seyfert 2 galaxies, as inferred from hard X-ray observations, on timescales from months to several years. We show that a significant variation of NH (from 20% to 80%) is observed in almost all (22 of 25) of the sources with multiple X-ray observations, although X-ray absorption never vanishes. For a subsample of 11 sources observed at least five times, the typical variation time, as defined by a structure function, is less than 1 yr for both heavily absorbed (NH ~ 1023 cm-2) and moderately absorbed (NH ~ 1022 cm-2) sources. These variations rule out the simplest version of the unified models, based on a homogeneous obscuring torus, and suggest the presence of clumpy circumnuclear material on a scale well below a parsec. We propose a modification of the torus model in which an overabundance of slightly dusty broad emission-line region (BELR) clouds obscures the BELR. The BELR needs, like the torus, to have an axisymmetric structure. This model is closely related to that of Elvis for type 1 active galactic nuclei (AGNs). For lightly obscured AGNs (NH ~ 1022 cm-2), the structure function shows an increase at a timescale of ~5 yr, indicating a second absorber, most probably on a 5-10 pc scale associated with the host galaxy.
THE BE STARS

This is one of the review papers celebrating the centenary of the Astronomical Society of the Pacific, see also 004.037. Research on Be stars from the early work of Merrill and Struve to the present is reviewed, including recent observations from space. A number of models which have been proposed to explain the Be phenomenon are discussed, and the evolutionary status of Be stars is considered.
Pioneer Venus Mission Plan for Atmospheric Probes and an Orbiter

The mission concept is described for a spin-stabilized spacecraft being designed to deliver an array of aerodynamic probes over the surface of Venus, and, on a second flight mission, to inject the spacecraft into a Venusian orbit. Large and Small Probes and the instrumented 'Bus' structure will enter the Venusian atmosphere and directly measure its characteristics. An orbiting configuration of the same basic Bus spacecraft will serve as a platform from which to examine the planetary environment, the outer atmosphere and its interaction with the solar wind, as well as surface topography. The orbital mission will extend over a complete revolution of the planet around the sun and around its own axis. Requirements for cost effectiveness and firm adherence within early cost projections are emphatic program guidelines which affect every major element of the mission plan and conceptual design.
Maximum likelihood estimation for small noise multiscale diffusions

We study the problem of parameter estimation for stochastic differential equations with small noise and fast oscillating parameters. Depending on how fast the intensity of the noise goes to zero relative to the homogenization parameter, we consider three different regimes. For each regime, we construct the maximum likelihood estimator and we study its consistency and asymptotic normality properties. A simulation study for the first order Langevin equation with a two scale potential is also provided.
Centers of F-purity

In this paper, we study a positive characteristic analogue of the centers of log canonicity of a pair (R, Δ). We call these analogues centers of F-purity. We prove positive characteristic analogues of subadjunction-like results, prove new stronger subadjunction-like results, and in some cases, lift these new results to characteristic zero. Using a generalization of centers of F-purity which we call uniformly F-compatible ideals, we give a characterization of the test ideal (which unifies several previous characterizations). Finally, in the case that Δ = 0, we show that uniformly F-compatible ideals coincide with the annihilators of the $${\mathcal{F}(E_R(k))}$$ -submodules of E R (k) as defined by Lyubeznik and Smith.
Sulfoxides as chiral complexation agents. Conformational enantiomer resolution and induced circular dichroism of bilirubins

Abstract Bilirubin-IXα, the end product of porphyrin metabolism in mammals and the neurotoxic yellow-orange pigment of jaundice, exhibits a strong tendency to fold like a book into either of two interconverting enantiomeric conformations, which are further stabilized by intramolecular hydrogen bonding. Bilirubin exhibits optical activity in R-(-)-ethylmethylsulfoxide solvent, as seen by moderately strong bisignate circular dichroism Cotton effects (Δϵmax452=+10.9,Δϵmax404=-4.5), and in dichloromethane solution in the presence of 2M R-(+)-methyl-p-tolylsulfoxide its circular dichroism spectrum (Δϵ463max=+11.2,Δϵ412max=-7.1) is comparably strong. As observed earlier for chiral recognition of bilirubin by optically active amines and serum albumins, the optically active sulfoxide acts as a chiral complexation agent to induce an asymmetric transformation of bilirubin, whose bisignate circular dichroism spectra are characteristic of an exciton splitting arising from interaction of the two component dipyrrinone chromophores.
WEAVER: A Knowledge-Based Routing Expert

WEAVER, a channel/switchbox knowledge-based routing program, simultaneously considers all the important routing metrics including 100 percent routability, minimum routing area, minimum wire length, and the minimum number of vias. It allows prerouted nets and user interaction throughout the entire routing process, while relaxing the unnecessary contraints of assigning different directions?constraints imposed by all of the current channel and switchbox routers. A grid-based router using two interconnection layers, WEAVER can be easily expanded to route any shape routing area such as T or +. Implemented in OPSS, a production system language, WEAVER routinely produces routings requiring less area than routers that focus on a single routing metric.
Sharp Geometric Upper Bounds on Resonances for Surfaces with Hyperbolic Ends

We establish a sharp geometric constant for the upper bound on the resonance counting function for surfaces with hyperbolic ends. An arbitrary metric is allowed within some compact core, and the ends may be of hyperbolic planar, funnel, or cusp type. The constant in the upper bound depends only on the volume of the core and the length parameters associated to the funnel or hyperbolic planar ends. Our estimate is sharp in that it reproduces the exact asymptotic constant in the case of finite-area surfaces with hyperbolic cusp ends, and also in the case of funnel ends with Dirichlet boundary condtiions.
A MAD Q-set

A MAD (maximal almost disjoint) family is an infinite subset A of the infinite subsets of ω = {0, 1, 2, . . .} such that any two elements of A intersect in a finite set and every infinite subset of ω meets some element of A in an infinite set. A Q-set is an uncountable set of reals such that every subset is a relative Gδ set. It is shown that it is relatively consistent with ZFC that there exists a MAD family which is also a Q-set in the topology in inherits a subset of P (ω) = 2.
Far-Ultraviolet Fluorescence of Molecular Hydrogen in IC 63*

We present observations of H2 fluorescence at wavelengths between 1000 and 1200 A from the bright reflection nebula IC 63. Observations were performed with the Berkeley spectrograph aboard the ORFEUS II mission. To the best of our knowledge, this is the first detection of astrophysical H2 fluorescent emission at these wavelengths (excluding planetary atmospheres). The shape of the spectrum is well described by the model of Sternberg. The absolute intensity, however, is fainter by a factor of 10 than an extrapolation from observations at longer ultraviolet wavelengths. Of the mechanisms that might help to reconcile these observations, optical depth effects in the fluorescing H2 itself are the most promising (or at least the most difficult to rule out).
Polarization of the cosmic background radiation

The technique and results of a measurement of the linear polarization of the cosmic background radiation at a wavelength of 9 mm are discussed. Data taken between 1978 May and 1980 February from both the Northern Hemisphere (Berkeley latitude 38 deg N) and the Southern Hemisphere (Lima latitude 12 deg S) over 11 declinations from -37 to +63 deg show the radiation to be essentially unpolarized over all areas surveyed. Fitting all data gives the 95% confidence level limit on a linearly polarized component of 0.3 mK for spherical harmonics through third order. A fit of all data to the anisotropic axisymmetric model of Rees (1968) yields a 95% confidence level limit of 0.15 mK for the magnitude of the polarized component. Constraints on various cosmological models are discussed in light of these limits.
Comparing methods for dynamic airspace configuration

This paper compares airspace design solutions for dynamically reconfiguring airspace in response to nominal daily traffic volume fluctuation. Airspace designs from seven algorithmic methods and a representation of current day operations in Kansas City Center were simulated with two times today's demand traffic. A three-configuration scenario was used to represent current day operations. Algorithms used projected unimpeded flight tracks to design initial 24-hour plans to switch between three configurations at predetermined reconfiguration times. At each reconfiguration time, algorithms used updated projected flight tracks to update the subsequent planned configurations. Compared to the baseline, most airspace design methods reduced delay and increased reconfiguration complexity, with similar traffic pattern complexity results. Design updates enabled several methods to as much as half the delay from their original designs. Freeform design methods reduced delay and increased reconfiguration complexity the most.
Development of Commercially Viable Compliant Mechanisms Using the Pseudo-Rigid-Body Model: Case Studies of Parallel Mechanisms

Analysis and synthesis of compliant mechanisms has recently been the subject of significant study in the research community. This focus has led to a number of design approaches for developing compliant mechanisms. This paper describes the value of using the Pseudo-Rigid-Body Model (PRBM) to design compliant mechanisms for commercial products. Application of the PRBM is illustrated through the development of two parallel mechanisms: a bicycle derailleur and parallel-motion bicycle brakes. The PRBM allows compliant mechanisms to be modeled and analyzed as rigid-body mechanisms and significantly reduces the complexity of analysis. Mechanisms with straightforward properties are used to demonstrate the use of the PRBM to design commercially viable compliant mechanisms for required motion and force-deflection characteristics.
Resolution of Terminal 1,2-Diols via Silyl Transfer

Through kinetic analysis and optimization, we report an improved resolution of terminal 1,2-diols via asymmetric silyl transfer. Because the reaction is a regiodivergent resolution, the monoprotected product could be isolated in excess of 95:5 er and 40% yield. The described method offers a means of chemically differentiating a terminal 1,2-diol with concomitant resolution of the enantiomers.
Impingement of a low Reynolds number turbulent circular jet onto a flat plate at normal incidence

The velocity field of a circular water jet impinging onto a flat plate has been measured using particle image velocimetry, or PIV. The velocity field has been recorded at several instants in time, producing thousands of simultaneous two-dimensional velocity measurements for each realization. The instantaneous velocity, vorticity and rate-of-strain fields reveal the interaction of vortices near the impinging wall within the radial wall jet downstream from the stagnation point. An ensemble average of the instantaneous fields produces a mean velocity field of the jet flow, which reveals many of the processes leading to boundary layer separation and vortex breakaway within the wall jet. The PIV system extracts the velocity measurements using a two-dimensional autocorrelation method, and can obtain thousands of highly accurate velocity measurements within a few minutes. The structure found in these experiments may be similar to the ground level structure of atmospheric microburst phenomena.
The Stellar Halo in the Large Magellanic Cloud: Mass, Luminosity, and Microlensing Predictions

Recently obtained kinematic data have shown that the Large Magellanic Cloud (LMC) possesses an old stellar halo. In order to further characterize the properties of this halo, parametric King models are fitted to the surface density of RR Lyrae stars. Using data from both the MACHO and OGLE II microlensing surveys, the model fits yield the center of their distribution at α = 5h211 ± 08, δ = -69°45' ± 6' (J2000.0) and a core radius of 1.42 ± 0.12 kpc. As a check, the halo model is compared with RR Lyrae star counts in fields near the LMC's periphery previously surveyed with photographic plates. These data, however, require a cautious interpretation. Several topics regarding the LMC stellar halo are discussed. First, the properties of the halo imply a global mass-to-light ratio of M/LV = 5.3 ± 2.1 and a total mass of × 1010 M☉ for the LMC, in good agreement with estimates based on the rotation curve. Second, although the LMC's disk and halo are kinematically distinct, the shape of the surface density profile of the halo is remarkably similar to that of the young disk. For example, the best-fit exponential scale length for the RR Lyrae stars is 1.47 ± 0.08 kpc, which compares to 1.46 kpc for the LMC's blue light. In the Galaxy, the halo and disk do not resemble each other like this. Finally, a local maximum in the LMC's microlensing optical depth due to halo-on-disk stellar self-lensing is predicted. For the parameters of the stellar halo obtained, this maximum is located near MACHO events LMC-4 and LMC-23 and is large enough to possibly account for these two events but not for all of the observed microlensing.
Sub-shot-noise quantum optical interferometry: a comparison of entangled state performance within a unified measurement scheme

Phase measurement using a lossless Mach–Zehnder interferometer with certain entangled N-photon states can lead to a phase sensitivity of the order of 1/N, the Heisenberg limit. However, previously considered output measurement schemes are different for different input states to achieve this limit. We show that it is possible to achieve this limit just by the parity measurement for all the commonly proposed entangled states. Based on the parity measurement scheme, the reductions of the phase sensitivity in the presence of photon loss are examined for the various input states.
Amino Acid Esters and Amides for Reductive Amination of Mucochloric Acid: Synthesis of Novel γ‐Lactams, Short Peptides and Antiseizure Agent Levetiracetam (Keppra®)

A simple methodology utilizing mucochloric acid anddifferent α- and β-amino acid esters, amides and shortpeptides for the synthesis of novel γ-lactam and γ-lactam-based short peptides was developed. The synthesis of an antiseizure agent, Levetiracetam (Keppra®) was demonstrated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Sulfur-containing 2-arylquinolinemethanols as potential antimalarials

The synthesis and antimalarial activity of six new 2-arylquinoline-4-methanols is described. The compounds bearing a sulfur were prepared to determine if antimalarial activity can be retained while photo-reactivity and phototoxicity is diminished by such substituents. The observed antimalarial activity of some of the new compounds show this to be possible.
Zeolite-catalyzed chlorination of toluene by sulfuryl chloride: The role of sulfuryl chloride decomposition in chlorination

The catalytic decomposition of sulfuryl chloride was studied over dried sodium forms of zeolites ZSM-5, L, and Y. NaZSM-5 did not catalyze the decomposition, whereas NaKL and NaY did. During the chlorination of aromatic hydrocarbons using NaKL or NaY, the chlorinating agent sulfuryl chloride must compete with molecular chlorine produced by its own decomposition. The rate of reaction with molecular chlorine alone is much faster than that with sulfuryl chloride. In the presence of sulfuryl chloride, however, the rate of chlorination by molecular chlorine is greatly reduced. Both chlorinating agents use Lewis acid sites, suggesting that these sites are predominantly covered by sulfuryl chloride. Sulfuryl chloride is slightly more selective for para-chlorotoluene than is molecular chlorine. NaZSM-5 catalyzes chlorination using either molecular chlorine or sulfuryl chloride alone, but the latter reactant is not simultaneously decomposed by NaZSM-5. The decomposition may require a basic site adjacent to the Lewis acid site, and NaZSM-5 may not possess basic sites of sufficient strength.
Lower Bounds for Nodal Sets of Dirichlet and Neumann Eigenfunctions

Let \({\phi}\) be a Dirichlet or Neumann eigenfunction of the Laplace-Beltrami operator on a compact Riemannian manifold with boundary. We prove lower bounds for the size of the nodal set \({\{\phi = 0\}}\) .
CLAS: A large acceptance spectrometer for intermediate-energy electromagnetic nuclear physics

The CEBAF Large Acceptance Spectrometer (CLAS) has been operating for nuclear physics experiments since December 1997. A description of its individual components and their specifications is given, followed by a description of the overall spectrometer performance and a summary of the types of physics data which have been taken to date.
Perfect lattice actions with and without chiral symmetry

We use perturbation theory to construct perfect lattice actions for fermions and gauge fields by blocking directly from the continuum. When one uses a renormalization group transformation that preserves chiral symmetry the resulting lattice action for massless fermions is chirally symmetric but nonlocal. When the renormalization group transformation breaks chiral symmetry the lattice action becomes local but chiral symmetry is explicitly broken. In particular, starting with a chiral gauge theory in the continuum one either obtains a lattice theory which is gauge invariant but nonlocal, or a local theory with explicitly broken gauge invariance. In both cases the spectrum of the lattice theory is identical with the one of the continuum and the anomaly is correctly reproduced. We also apply our techniques to vector-like theories. In particular we propose a new renormalization group transformation for QCD and we optimize its parameters for locality of the perfect action.
Femtochemistry: Atomic-Scale Dynamics of the Chemical Bond†

This anthology, which is adapted from the Nobel Lecture, gives an overview of the field of Femtochemistry from a personal perspective, encompassing our research at Caltech and focusing on the evolution of techniques, concepts, and new discoveries. In developing femtochemistrythe study of molecular motions in the ephemeral transition states of physical, chemical, and biological changeswe have harnessed the powerful concept of molecular coherence and developed ultrafast-laser techniques for observing these motions. Femtosecond resolution (1 fs = 10-15 s) is the ultimate achievement for studies of the dynamics of the chemical bond at the atomic level. On this time scale, matter wave packets (particle-type) can be created and their coherent evolution as a single-molecule trajectory can be observed. The field began with simple systems of a few atoms and has reached the realm of the very complex in isolated, mesoscopic, and condensed phases and in biological systems such as proteins and DNA. It also offers new ...
The Dynamics of Collective Reputation

I present a stochastic version of Tirole's (1996) collective reputation model. In equilibrium, group behavior is persistent due to complementarity between the current incentives of group members and the group's reputation, which depends on its history. A group can maintain a strong reputation even as conditions become unfavorable, but an improvement in the environment may not help a group with a poor reputation. I also connect the model to the theory of statistical discrimination and show that the same mechanism can explain why discrimination might persist over time.
HIGH FIELD 31P ENDOR OF MNALPO4-20 : DIRECT EVIDENCE FOR FRAMEWORK SUBSTITUTION

The incorporation of Mn(II) into framework sites in the aluminophosphate zeotype AlPO4-20, an analog of sodalite, has been investigated using pulsed electron nuclear double resonance (ENDOR) spectroscopy at 95 GHz. The field sweep echo-detected EPR spectrum showed the presence of a single Mn(II) site with a 55Mn hyperfine coupling of 8.7 mT. ENDOR spectra, recorded using the Mims and Davies sequences, consist of an 27Al signal at the Larmor frequency and a 31P doublet corresponding to a hyperfine coupling of 8 MHz. The symmetry of the doublet about the 31P Larmor frequency indicates that it originates from the MS = ±1/2 manifolds and that the interaction is primarily isotropic. The relatively large 31P hyperfine interaction and the weak interaction with 27Al provide unique and direct evidence for Mn(II) substitution of framework Al. X-band electron spin echo envelope modulation (ESEEM) measurements showed only signals at the 1H, 14N, 27Al, and 31P Larmor frequencies. The first two are due to weak dipolar ...
Synthesis, Computed Stability, and Crystal Structure of a New Family of Inorganic Compounds: Carbonophosphates

Ab initio-based high-throughput computing and screening are now being used to search and predict new functional materials and novel compounds. However, systematic experimental validation on the predictions remains highly challenging, yet desired. Careful comparison between computational predictions and experimental results is sparse in the literature. Here we report on a systematic experimental validation on previously presented computational predictions of a novel alkali carbonophosphate family of compounds. We report the successful hydrothermal synthesis and structural characterization of multiple sodium carbonophosphates. The experimental conditions for formation of the carbonophosphates and the computational results are compared and discussed. We also demonstrate topotactic chemical de-sodiation of one of the compounds, indicating the potential use of this novel class of compounds as Li+ or Na+ insertion electrodes.
Increased urinary excretion of C5b-9 distinguishes passive Heymann nephritis in the rat.

Increased urinary excretion of C5b-9 distinguishes passive Heymann nephritis in the rat. Increased urinary excretion of C5b-9 distinguishes passive Heymann nephritis from other forms of experimental glomerulonephritis in the rat. In the passive Heymann nephritis (PHN) model of membranous nephropathy (MN) subepithelial deposits form from anti-Fx1A antibody reacting with antigen expressed on the glomerular epithelial cell membrane followed by membrane patching and shedding of immune complexes. Immune complex deposits are accompanied by deposits of C5b-9 which is required for the mediation of proteinuria. We tested the hypothesis that C5b-9 assembly on the epithelial cell membrane might result in C5b-9 excretion in the urine, which would distinguish this autoimmune mechanism of MN from other processes that result in subepithelial immune complex deposits. Using monoclonal antibodies developed to rat C6 and a rat C5b-9 neoantigen, in a sensitive ELISA assay, elevated urinary excretion of rat C5b-9 was documented in PHN associated with on-going glomerular immune deposit formation. No urinary C5b-9 was detectable in MN induced by an exogenous antigen (cationized IgG) despite equivalent glomerular C5b-9 deposits, or in models of nephrotoxic nephritis, subendothelial immune complex nephritis, anti-mesangial cell membrane antibody-induced nephritis or two non-immune nephropathies. Infusion of preformed C5b-9 in proteinuric animals excluded glomerular filtration of C5b-9 as a contributing mechanism to urinary C5b-9 excretion. We conclude that in the rat, increased urinary excretion of C5b-9 is a marker of MN induced by antibody to a glomerular epithelial cell antigen. Urine C5b-9 excretion reflects active glomerular immune deposit formation and distinguishes MN induced by this mechanism from other forms of MN as well as from other glomerular diseases with equivalent glomerular C5b-9 deposits.
The generation of Brønsted and Lewis acid sites on the surface of silica by addition of dopant cations

Abstract Pyridine adsorption was used to study the acidic properties of silica doped with the following cations: Sc3+, Mg2+, Fe2+, Fe3+, Zn2+, Al3+, and Ga3+. All samples were exposed to pyridine at 423 K and subsequently evacuated at successively higher temperatures to 723 K. Infrared spectra of the adsorbed pyridine indicated that all of these cations generated Lewis acid sites. This can be explained by the presence of coordinatively unsaturated dopant cations on the surface of silica, in accord with a model based on Pauling's electrostatic bond strength rules. The infrared frequency of the 19b band of pyridine adsorbed on these Lewis acid sites was found to increase with increasing electronegativity of the dopant cation. It is suggested that both of these quantities are related to the strength of the Lewis acid sites. Bronsted acid sites were also observed by infrared spectroscopy for Sc3+, Al3+, and Ga3+ on silica. These dopant cations are believed to be bonded tetrahedrally on the surface of silica, generating bridging hydroxyl groups between the dopant cation and Si4+. As for zeolite catalysts, the proton associated with these groups and required for charge neutrality is the Brofnsted acid site. Finally, Brofnsted acid sites can also be generated on silica by highly electronegative anions, such as HPO2−4, which generate Brofnsted acidity in a different manner.
Micro-control actions of actuator patches laminated on hemispherical shells

Spherical shell-type structures and components appear in many engineering systems, such as radar domes, pressure vessels, storage tanks, etc. This study is to evaluate the micro-control actions and distributed control effectiveness of segmented actuator patches laminated on hemispheric shells. Mathematical models and governing equations of the hemispheric shells laminated with distributed actuator patches are presented first, followed by formulations of distributed control forces and micro-control actions including meridional/circumferential membrane and bending control components. Due to difficulties in analytical solution procedures, assumed mode shape functions based on the bending approximation theory are used in the modal control force expressions and analyses. Spatially distributed electromechanical actuation characteristics resulting from various meridional and circumferential actions of segmented actuator patches are evaluated. Distributed control forces, patch sizes, actuator locations, micro-control actions, and normalized control authorities of a free-floating hemispheric shell are analyzed in case studies. Parametric analysis indicates that (1) the control forces and membrane/bending components are mode and location dependent, (2) actuators placed near the free boundary contributes the most significant control actions, and (3) the meridional/circumferential membrane control actions dominate the overall control effect.
X-Ray Constraints on Cluster Magnetic Fields

Lower limits to the intracluster magnetic field are derived from modeling broad band X-ray spectra of 6 galaxy clusters with radio halos (A401, A754, A1367, Coma = A1656, A2256, and A2319). The 0.710 keV spectra for all clusters were obtained with the Advanced Satellite for Cosmology and Astrophysics (ASCA) Gas Imaging Spectrometer (GIS). For A401, A754, A1367, and A1656, data from the HEA01-A2 High Energy Detector (HED) (2-60 keV) was included in a joint fit to further constrain the allowed non­ thermal component. Upperlimits to the non-thermal X-ray emission are a factor of ~ 10 improvement over previous values. Lower limits to the average magnetic field derived from these upperlimits and the radio spectral parameters range from 0.08-0.30 JJLG. A seed intracluster field amplified by turbulence from galaxy motion through the intracluster medium should have an average value in the range ~ 0.1-0.2, thus the lack of any detections makes it unlikely that field amplification is due to galaxy wakes. In addition, all of these clusters have an asymmetric surface brightness distribution while several also have X-ray spectroscopic evidence of a merger. We suggest that cluster mergers rather than galaxy wakes are the source of the magnetic field amplification.
Optical quantum control of localized spins in semiconductors

Single electrons localized in a semiconductor can nowadays be addressed using nano-optical techniques. Dilute impurity centers represent an example where one or two localized electrons can be addressed selectively. I will discuss theoretically optical techniques to control the spin of one and two electrons at the quantum level in these systems. In the case of two spin, this entails the ability of generating and controlling entanglement
Quantum Product on the Big Phase Space and the Virasoro Conjecture

We first study the quantum product on the big phase space defined by gravitational Gromov-Witten invariants. We then use this product to give an interpretation for various topological recursion relations and also use it to study the Virasoro conjecture proposed by Eguchi-Hori-Xiong and Katz. We will give a recursive formulation to the Virasoro conjecture and study properties of relevent vector fields, which will be useful in proving and applying the Virasoro conjecture for all genera. In the genus-2 case, we will prove that the genus-2 Virasoro conjecture can be reduced to the $L_{1}$ constraint for any manifold. In the case when the quantum cohomology of the underlying manifold is not too degenerate (in particular, is semisimple) we will prove an explicit formula expressing the generating function of genus-2 Gromov-Witten invariants in terms of genus-0 and genus-1 data. This result reduces the genus-2 Virasoro conjecture to a genus-1 problem for such manifolds.
Biaryls via Suzuki Cross-Couplings Catalyzed by Nickel on Charcoal☆

Abstract Using the heterogeneous catalyst ‘Ni/C’, biaryl bonds can be made between functionalized aryl chlorides and boronic acids in good isolated yields. A standard set of conditions has been developed which applies to a variety of reaction partners.
Reliability challenges for low voltage/low power integrated circuits

This review paper discusses reliability considerations for low voltage/low power integrated circuit technologies. This growing market will continue to be dominated by scaled CMOS, with silicon on insulator technology growing in importance due to improved performance and reliability over bulk, low power CMOS. Power dissipation, performance, and reliability will be traded off at all levels of system design ; this paper concentrates on device level issues. An aggressive low voltage/low power technology development path could yield a CMOS/SOI technology with 40 nm junctions, 5 nm gate oxides, and 0.9 V supplies. Such an aggressive low voltage/low power technology alters many traditional reliability problems such as metallization failure, oxide breakdown, hot carrier effects, electrostatic discharge, leakage currents, soft errors and analogue circuit noise. SOI brings additional reliability concerns such as heat dissipation through the buried oxide, bipolar latch, and back interface effects. This paper examines several of these issues and identifies a number of present and future reliability challenges for low voltage/low power technology.
The Effects of Surface Modification on Spacecraft Charging Parameters

Charging of materials by incident radiation is affected by both environmental and physical conditions. Modifying a material's physical surface will change its reflection, transmission, and absorption of the incident radiation which are integrally related to the accumulation of charge and energy deposition in the material. General arguments for incident and emitted photons, electrons, and ions are considered. An optical analysis of the effects of surface modification on spacecraft charging parameters on prototypical polyimide Kapton HN and Cu samples is presented. Samples were roughened with abrasive compounds ranging from 0.5 to 10 μm in size, comparable to the range of incident wavelengths. They were also contaminated with thin layers of DC 704 diffusion pump oil. Using a UV/VIS/NIR light source and a diffraction grating spectrometer, measurements were performed on pristine and modified materials. The measured spectra confirmed that surface modifications induce expected changes in optical reflection, transmission, and absorption. The generally increased absorption observed results in increased photon energy deposited in the material, leading to increased charge emission through the photoelectric effect.
Copper-catalyzed coupling of alkylamines and aryl iodides: an efficient system even in an air atmosphere.

A mild method for the copper-catalyzed amination of aryl iodides is reported. This operationally simple C−N bond-forming protocol uses CuI as the catalyst and ethylene glycol as ligand in 2-propanol. A variety of functionalized aryl iodides as well as several amines were efficiently coupled using this method. This catalytic amination procedure is relatively insensitive to moisture and can be performed under an air atmosphere with comparable yield. Preliminary results on the amination of aryl bromides are also described.
Facile: a symmetric integration of concurrent and functional programming

Facile is a symmetric integration of concurrent and functional programming. The language supports both function and process abstraction. Functions may be defined and used within processes, and processes can be dynamically created during expression evaluation. In this work we present two different descriptions of the operational semantics of Facile. First, we develop a structural operational semantics for a small core subset of Facile using a labeled transition system. Such a semantics is useful for reasoning about the operational behavior of Facile programs. We then provide an abstract model of implementation for Facile: theConcurrent and Functional Abstract Machine (C-FAM). The C-FAM executes concurrent processes evaluating functional expressions. The implementation semantics includes compilation rules from Facile to C-FAM instructions and execution rules for the abstract machine. This level of semantic description is suitable for those interested in implementations.
Linearity of volume hologram out-coupling for wavelength-division demultiplexing

Close-form expressions are used to analyze the spatial and angular linearity of the out-coupling volume holograms in wavelength division multiplexing/demultiplexing (WDM/WDDM). Optimal spatial linear out-coupling regimes are located. Some design criteria for volume holographic WDDM applicable to 800nm, 1300nm, and 1550nm optical wavelength window are addressed. As a design example, we deploy these criteria to design a passive surface normal input/output wavelength division demultiplexer working in the wavelength range of 768-864 nm. Coupling of the demultiplexed optical signal from the substrate modes to a linear multi-mode fiber array is verified with experiment. The importance of the spatial linearity of the out-coupling in volume holographic WDDM structure is highlighted and possible coupling of the signal to linear single-mode fiber array is mentioned.
Cell density alters matrix accumulation in two distinct fractions and the mechanical integrity of alginate-chondrocyte constructs

Chondrocyte density in articular cartilage is known to change with the development and growth of the tissue and may play an important role in the formation of a functional extracellular matrix (ECM). The objective of this study was to determine how initial chondrocyte density in an alginate hydrogel affects the matrix composition, its distribution between the cell-associated (CM) and further removed matrix (FRM) fractions, and the tensile mechanical properties of the developing engineered cartilage. Alginate constructs containing primary bovine chondrocytes at densities of 0, 4, 16, and 64 million cells/ml were fabricated and cultured for 1 or 2 weeks, at which time structural, biochemical, and mechanical properties were analyzed. Both matrix content and distribution varied with the initial cell density. Increasing cell density resulted in an increasing content of collagen and sulfated-glycosaminoglycan (GAG) and an increasing proportion of these molecules localized in the CM. While the equilibrium tensile modulus of cell-free alginate did not change with time in culture, the constructs with highest cell density were 116% stiffer than cell-free controls after 2 weeks of culture. The equilibrium tensile modulus was positively correlated with total collagen (r2 = 0.47, p < 0.001) and GAG content (r2 = 0.68, p < 0.001), and these relationships were enhanced when analyzing only those matrix molecules in the CM fraction (r2 = 0.60 and 0.72 for collagen and GAG, respectively, each p < 0.001). Overall, the results of this study indicate that initial cell density has a considerable effect on the developing composition, structure, and function of alginate–chondrocyte constructs.
Bremsstrahlung from ions

Abstract We discuss various theoretical (numerical and analytical) results for bremsstrahlung spectra from isolated ions and methods for their calculations. Particular attention is paid to screening of the nuclear charge by the remaining electrons and to the transition through ionic species from the neutral atom to the bare nucleus. A simple method for calculation of the general characteristics of bremsstrahlung from plasmas is discussed.
Optimum Truncation of a Gaussian Beam in the Presence of Random Jitter

I consider the far-field (or focal plane) irradiance distribution of a Gaussian beam that is truncated by a circular aperture in the presence of random angular jitter. First, for absence of jitter, I derive an accurate analytic approximation for the irradiance distribution within the main lobe of the beam for the case in which the beam diameter is less than the aperture diameter. Then I obtain the corresponding mean irradiance distribution in the presence of circularly symmetric normally distributed jitter. By maximizing the on-axis intensity I obtain the optimum ratio of the beam diameter to the aperture diameter in the presence of jitter and present results for the corresponding maximum on-axis intensity and encircled power as a function of the jitter statistics.
A Neural Model of how Horizontal and Interlaminar Connections of Visual Cortex Develop into Adult Circuits that Carry Out Perceptual Grouping and Learning

A neural model suggests how horizontal and interlaminar connections in visual cortical areas V1 and V2 develop within a laminar cortical architecture and give rise to adult visual percepts. The model suggests how mechanisms that control cortical development in the infant lead to properties of adult cortical anatomy, neurophysiology and visual perception. The model clarifies how excitatory and inhibitory connections can develop stably by maintaining a balance between excitation and inhibition. The growth of long-range excitatory horizontal connections between layer 2/3 pyramidal cells is balanced against that of short-range disynaptic interneuronal connections. The growth of excitatory on-center connections from layer 6-to-4 is balanced against that of inhibitory interneuronal off-surround connections. These balanced connections interact via intracortical and intercortical feedback to realize properties of perceptual grouping, attention and perceptual learning in the adult, and help to explain the observed variability in the number and temporal distribution of spikes emitted by cortical neurons. The model replicates cortical point spread functions and psychophysical data on the strength of real and illusory contours. The on-center, off-surround layer 6-to-4 circuit enables top-down attentional signals from area V2 to modulate, or attentionally prime, layer 4 cells in area V1 without fully activating them. This modulatory circuit also enables adult perceptual learning within cortical area V1 and V2 to proceed in a stable way.