cssi/SciSciGPT-SciSciNet huggingface dataset:
Relationship of biogenic amines to behavior.

Abstract Present data support the proposal that dopaminergic fibers play an important role in the maintenance of intracranial self-stimulation. In addition, amphetamine-induced motor activity as well as the sterotypies produced by this drug were also found to be dependent upon intact dopaminergic fibers. Evidence was also presented that serotonin fibers may modulate the behavioral actions of amphetamine by acting as an inhibitory transmitter.
Laser Weld Penetration Estimation Using Temperature Measurements

Penetration depth is an important factor critical to the quality of a laser weld. This paper examines the feasibility of using temperature measurements on the bottom surface of the work-piece to estimate weld penetration. A three-dimensional analytical model relating penetration depth, weld bead width and welding speed to temperature distribution at the bottom surface of the workpiece is developed. Temperatures on the bottom surface of the workpiece are measured using infrared thermocouples located behind the laser beam. Experimental results from bead-on-plate welds on low carbon steel plates of varying thickness at different levels of laser power and speeds validate the model and show that the temperature on the bottom surface is a sensitive indicator of penetration depth. The proposed model is computationally efficient and is suitable for on-line process monitoring application.
Overview of recent advances in excimer laser technology at Los Alamos

From among the areas of excimer laser development at Los Alamos two are selected for further discussion: ultra-high brightness excimer laser systems and discharge-pumped XeF(C..-->..A) lasers operating in the blue-green portion of the spectrum. Two different high brightness systems are described. One is based on small-aperture KrF amplifiers, while the other is based on a large-aperture XeCl amplifier. The XeF(C..-->..A) laser is tunable from 435 to 525 nm, and may one day become a viable alternative to pulsed dye lasers for many applications. 14 refs., 4 figs.
Clustered volatility in multiagent dynamics

Abstract Large distributed multiagent systems are characterized by vast numbers of agents trying to gain access to limited resources in an unpredictable environment. Agents in these systems continuously switch strategies in order to opportunistically find improvements in their utilities. We analyzed the fluctuations around equilibrium that arise from strategy switching and discovered the existence of a new phenomenon. It consists of the appearance of sudden bursts of activity that punctuate the fixed point, and is due to an effective random walk consistent with overall stability. This clustered volatility is followed by relaxation to the fixed point but with different strategy mixes from the previous one. This bursting phenomenon is the result of the system continually changing between strategy configurations that are consistent with the overall equilibrium.
Collective additive tree spanners of bounded tree-breadth graphs with generalizations and consequences

In this paper, we study collective additive tree spanners for families of graphs enjoying special Robertson-Seymour's tree-decompositions, and demonstrate interesting consequences of obtained results. We say that a graph G admits a system of @m collective additive tree r-spanners (resp., multiplicative tree t-spanners) if there is a system T(G) of at most @m spanning trees of G such that for any two vertices x,y of G a spanning tree T@?T(G) exists such that d"T(x,y)@?d"G(x,y)+r (resp., d"T(x,y)@?t@?d"G(x,y)). When @m=1 one gets the notion of additive tree r-spanner (resp., multiplicative tree t-spanner). It is known that if a graph G has a multiplicative tree t-spanner, then G admits a Robertson-Seymour's tree-decomposition with bags of radius at most @?t/2@? in G. We use this to demonstrate that there is a polynomial time algorithm that, given an n-vertex graph G admitting a multiplicative tree t-spanner, constructs a system of at most log"2n collective additive tree O(tlogn)-spanners of G. That is, with a slight increase in the number of trees and in the stretch, one can ''turn'' a multiplicative tree spanner into a small set of collective additive tree spanners. We extend this result by showing that if a graph G admits a multiplicative t-spanner with tree-width k-1, then G admits a Robertson-Seymour's tree-decomposition each bag of which can be covered with at most k disks of G of radius at most @?t/2@? each. This is used to demonstrate that, for every fixed k, there is a polynomial time algorithm that, given an n-vertex graph G admitting a multiplicative t-spanner with tree-width k-1, constructs a system of at most k(1+log"2n) collective additive tree O(tlogn)-spanners of G.
The Electronic Spectroscopy of Tyrosine and Phenylalanine Analogs in a Supersonic Jet: Basic Analogs

Abstract The spectroscopy of the basic analogs of phenylalanine and tyrosine has been studied in the gas phase in a supersonic jet using laser-induced fluorescence. There are six tyramine conformers, four phenethylamine conformers, and seven 4-methoxyphenethylamine conformers. Molecular mechanics calculations are used to deduce the most reasonable structures for these conformers. Dispersed emission spectra reveal that the major vibrational activity occurring in these molecules originates from the ring vibrational modes of their respective chromophores. The conformer fluorescence lifetimes of the three molecules were measured. All conformers of a given molecule have the same lifetime.
Dual-driver standing wave tube: acoustic impedance matching with robust repetitive control

In some acoustic applications, it may be desirable to make a shorter standing wave tube operate like a longer tube at the same driving frequency. The basic idea is to reduce the length of a long tube, and replace the removed section with a secondary driver. The problem is then to match the acoustic impedance at the boundary where the secondary driver is installed to that of the original system. Two control formulations were investigated for this problem: a two-input-two-output (TITO) and a single-input-single-output (SISO) formulation. The TITO formulation directly tracks the two acoustic variables associated with the desired acoustic impedance, while the SISO formulation minimizes the impedance matching error. The desired impedance containing a very lightly damped mode is embedded in the augmented plant for feedback control design. In addition to the balance realization method, the Schur method was used for model reduction for the high-order plant. Since the standing wave tubes are driven by tonal signals, repetitive control was incorporated into the control frameworks to achieve the desired performance. Good performance of impedance matching was obtained for both formulations. The SISO formulation yielded slightly wider bandwidth of good impedance matching than the TITO. The TITO formulation offered additional control to individual signals related to the acoustic impedance of interest.
Near-Field Structural Studies of Lipid Bilayers

We use a Near-field Scanning Optical Microscope (NSOM) in conjunction with a Photo Elastic Modulator (PEM) to conduct birefringence (ne-no) measurements with a spatial resolution of ∼80nm. With our current setup we are able to distinguish changes in retardance S on the order of 10-4 radians. Simultaneously while gathering information about S we extract information about the samples optical orientation θ referenced to the system's axis, with an accuracy of ∼7.24x10-4 radians. We use our system on 1,2-dipalmitoylphosphatidylchorline (DPPC) bilayers, which at room temperature are in the gel state, (i.e.: their acyl chains have a ∼32o degree azimulthal tilt with respect to the membranes normal). Modeling the membrane as a uniaxial crystal we are able determine the position of the acyl chains by measuring the birefringence and optical orientation. By controlling the temperature of our sample we hope to better study the structural changes that occur during phase transitions from gel to liquid states. The investigation of other lipid mixtures and the transformations they undergo during different phases will also be discussed.
A Fractal Origin for the Mass Spectrum of Interstellar Clouds. II. Cloud Models and Power-Law Slopes

Three-dimensional fractal models on grids of ~2003 pixels are generated from the inverse Fourier transform of noise with a power-law cutoff and exponentiated to give a lognormal distribution of density. The fractals are clipped at various intensity levels, and the mass and size distribution functions of the clipped peaks and their subpeaks are determined. These distribution functions are analogous to the cloud mass functions determined from maps of the fractal interstellar medium using various thresholds for the definition of a cloud. The model mass functions are found to be power laws with powers ranging from -1.6 to -2.4 in linear mass intervals as the clipping level increases from ~0.03 to ~0.3 of the peak intensity. The low clipping value gives a cloud-filling factor of ~10% and should be a good model for molecular cloud surveys. The agreement between the mass spectrum of this model and the observed cloud and clump mass spectra suggests that a pervasively fractal interstellar medium can be interpreted as a cloud/intercloud medium if the peaks of the fractal intensity distribution are taken to be clouds. Their mass function is a power law even though the density distribution function in the gas is a lognormal. This is because the size distribution function of the clipped clouds is a power law, and with clipping, each cloud has about the same average density. A similar result would apply to projected clouds that are clipped fractals, giving nearly constant column densities for power-law mass functions. The steepening of the mass function for higher clip values suggests a partial explanation for the steeper slope of the mass functions for star clusters and OB associations, which sample denser regions of interstellar gas. The mass function of the highest peaks is similar to the Salpeter initial mass function, suggesting again that stellar masses may be determined in part by the geometry of turbulent gas.
Theories of interstellar polarization

Abstract The experimental data to be explained by any theory of interstellar polarization are summarized. The expression for the ratio of polarization to absorption produced by a cloud of partially aligned small dust grains is put in a form applicable to all current theories of alignment. A semi-quantitative treatment is given of Gold's proposal that alignment is due to relative motion of dust through gas and this mechanism is shown to be inadequate to produce the observed polarization. Magnetic alignment theories are preferred. Equations are given for use when starlight passes through several clouds with various orientations. Any orienting mechanism can be tested by a statistical study of the observed distribution of polarization over neighbouring stars. Thus it appears tentatively that it is more plausible to assume that a galactic magnetic field lies along a spiral arm than that the field is randomly directed in the plane of the galaxy.
Characterization of three LYSO crystal batches

We report on three LYSO crystal batches characterized at the Caltech crystal laboratory for future HEP experiments: 25 20 cm long crystals for the SuperB experiment; 12 13 cm long crystals for the Mu2e experiment and 623 14×14×1.5 mm^3 plates with five holes for a LYSO/W Shashlik matrix for a beam test at Fermilab. Optical and scintillation properties measured are longitudinal transmittance, light output and FWHM energy resolution. Correlations between these properties are also investigated.
Catalytic Regioselective Sulfonylation of α-Chelatable Alcohols: Scope and Mechanistic Insight

This paper describes a convenient protocol for the regioselective sulfonylation of α-chelatable alcohols. Typically, the reaction of α-heterosubstituted alcohols with 1 equiv of p-TsCl and 1 equiv of Et3N in the presence of 2 mol % of Bu2SnO leads to rapid, regioselective, and exclusive monotosylation. The pKa of the amine was correlated to the reaction rate. A plausible mechanism for this reaction has been proposed on the basis of 119Sn NMR studies.
Rhodium catalyzed conjugated addition of unsaturated carbonyl compounds by triphenylbismuth in aqueous media and under an air atmosphere

Abstract In the presence of a rhodium catalyst, α,β-unsaturated esters and ketones react with triphenylbismuth in aqueous media and under an air atmosphere to give the corresponding conjugated addition products in high yields.
On the absorption by near-extremal black branes

We study the absorption of a minimally coupled scalar in the gravitational background created by a stack of near-extremal black three-branes, and more generally by M2-, M5- and Dp-branes. The absorption probability has the form P(l)=P0(l)fl(lambda), where P0(l) is the partial wave's absorption probability in the extremal case, and the thermal factor fl(lambda) depends on the ratio of the frequency of the incoming wave and the Hawking temperature, lambda=omega/piT. Using Langer-Olver's method, we obtain a low-temperature (lambdau1) asymptotic expansion for P(l) with coefficients determined recursively. This expansion, which turns out to be a fairly good approximation even for lambda~1, accounts for all power-like finite-temperature corrections to P0(l), and we calculate a few terms explicitly. We also show that at low temperature the absorption probability contains exponentially suppressed terms, and attempt to develop an approximation scheme to calculate those. The high-temperature expansion is also considered. For the s-wave, the low-temperature gravity result is consistent with the free finite-temperature field theory calculation, while for high temperature and higher partial waves we find a disagreement. As a check of the approximation methods used, we apply them to the D1-D5-brane system, and compare results to the known exact solution.
Cyclization via Carbolithiation of α-Amino Alkyllithium Reagents

We report a new route to tertiary α-amino stereocenters by sequential alkylation of α-amino nitriles followed by reductive lithiation of the nitrile and cyclization onto an alkene. Reductive lithiation of α-amino nitriles using lithium 4,4′-di-tert-butylbiphenylide (LiDBB) and subsequent intramolecular carbolithiation proceeded with modest to high diastereoselectivity to deliver cyclic or spirocyclic ring systems. The stereoselectivity of these intramolecular carbolithiations was examined using density function calculations to evaluate plausible transition state models.
Effects of Lipid Interactions on Model Vesicle Engulfment by Alveolar Macrophages

The engulfment function of macrophages relies on complex molecular interactions involving both lipids and proteins. In particular, the clearance of apoptotic bodies (efferocytosis) is enabled by externalization on the cell target of phosphatidylserine lipids, which activate receptors on macrophages, suggesting that (local) specific lipid-protein interactions are required at least for the initiation of efferocytosis. However, in addition to apoptotic cells, macrophages can engulf foreign bodies that vary substantially in size from a few nanometers to microns, suggesting that nonspecific interactions over a wide range of length scales could be relevant. Here, we use model lipid membranes (made of phosphatidylcholine, phosphatidylserine, and ceramide) and rat alveolar macrophages to show how lipid bilayer properties probed by small-angle x-ray scattering and solid-state 2H NMR correlate with engulfment rates measured by flow cytometry. We find that engulfment of protein-free model lipid vesicles is promoted by the presence of phosphatidylserine lipids but inhibited by ceramide, in accord with a previous study of apoptotic cells. We conclude that the roles of phosphatidylserine and ceramide in phagocytosis is based, at least in part, on lipid-mediated modification of membrane physical properties, including interactions at large length scales as well as local lipid ordering and possible domain formation.
Direct characterization of phase transformations and morphologies in moving reaction zones in Al/Ni nanolaminates using dynamic transmission electron microscopy

Abstract Phase transformations and transient morphologies are examined as exothermic formation reactions self-propagate across Al/Ni nanolaminate films. The rapid evolution of these phases and sub-micrometer morphological features requires nanoscale temporal and spatial resolution that is not available with traditional in situ electron microscopy. This work uses dynamic transmission electron microscopy to identify intermetallic products and phase morphologies, as exothermic formation reactions self-propagate in nanolaminate films grown with 3:2, 2:3 and 1:1 Al/Ni atomic ratios. Single-shot diffraction patterns with 15 ns temporal resolution reveal that the NiAl intermetallic forms within ∼15 ns of the reaction front’s arrival in all three types of films and is the only intermetallic phase to form, as the reactions self-propagate and quench very rapidly. Time-resolved imaging reveals a transient cellular morphology in the Al-rich and Ni-rich foils, but not in the equiatomic films. The cellular features in the Al-rich and Ni-rich films are attributed to a cooling trajectory through a two-phase field of liquid + NiAl.
Can the electroweak interaction break itself

Abstract I examine the possibility that the electroweak interaction breaks itself via the condensation of fermions in large representations of the weak SU(2) L gauge group.
On the physical origins of the negative index of refraction

The physical origins of negative refractive index are derived from a dilute microscopic model, producing a result that is generalized to the dense condensed phase limit. In particular, scattering from a thin sheet of electric and magnetic dipoles driven above resonance is used to form a fundamental description for negative refraction. Of practical significance, loss and dispersion are implicit in the microscopic model. While naturally occurring negative index materials are unavailable, ferromagnetic and ferroelectric materials provide device design opportunities. An erratum page was added to the end of the published paper on 11 November 2005.
Metal-free N-H insertions of donor/acceptor carbenes.

Synthetically useful transformations arise from the thermal decomposition of aryldiazoacetates in the presence of primary and secondary amines without the use of a metal catalyst. Thermally generated, free donor/acceptor carbenes directly undergo N–H insertion with amines through selective aza-ylide formation to afford a variety of α-amino esters in 53–96% yields.
Correction to “Topological nonrealization results via the Goodwillie tower approach to iterated loopspace homology”

In [1], the author showed that certain unstable modules over the mod 2 Steenrod algebra couldn’t be realized as the reduced mod 2 cohomology of a space. The modules have the form †M , where M is an unstable module of a special sort. The method of proof was to use a 2nd quadrant spectral sequence converging to H .X IZ=2/ to show that, were a space X to exist whose cohomology realized †M , H .X IZ=2/ could not admit a cup product compatible with Steenrod operations.
Automated whole-cell patch clamp electrophysiology of neurons in vivo

A robot, algorithm and software for automated in vivo intracellular electrophysiology are reported that can automatically perform whole-cell patch clamping in the living mouse brain with quality comparable to that for a trained human experimenter.
Tests for primordial non-Gaussianity

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as that which comes from topological defects. The tests we consider involve the cosmic microwave background (CMB), large-scale structure, high-redshift galaxies, and the abundances and properties of clusters. We find that the CMB is superior at finding non-Gaussianity in the primordial gravitational potential (as inflation would produce), while observations of high-redshift galaxies are much better suited to find non-Gaussianity that resembles that expected from topological defects. We derive a simple expression that relates the abundance of high-redshift objects in non-Gaussian models to the primordial skewness.
Improved control design variable linking for optimization of structural/control systems

A method is presented to integrate the design space for structural/control system optimization problems in the case of linear state feedback control. To make the truly simultaneous optimization of structural/control systems tractable, without increasing the number of control design variables, the conventional structural design variable linking idea is extended to the control system feedback gain matrix. In this paper a new control design variable linking scheme based on representing the feedback gain matrix as the linear combination of component matrices corresponding to different modes is introduced. The original nonlinear mathematical programming problem based on a finite element formulation and linear state feedback is replaced by a sequence of explicit approximate problems exploiting various approximation concepts such as structural and control design variable linkings, temporary constraint deletion, and first-order Taylor series expansion of nonlinear behavior constraints in terms of intermediate design variables. Examples that involve a variety of dynamic behavior constraints (including constraints on closed-loop eigenvalues, peak transient displacements, and peak actuator forces) are effectively solved by using the improved control design variable linking scheme presented.
Hydrocode modeling of oblique impacts: The fate of the projectile

Abstract— All impacts are oblique to some degree. Only rarely do projectiles strike a planetary surface (near) vertically. The effects of an oblique impact event on the target are well known, producing craters that appear circular even for low impact angles (>15° with respect to the surface). However, we still have much to learn about the fate of the projectile, especially in oblique impact events. This work investigates the effect of angle of impact on the projectile. Sandia National Laboratories' three-dimensional hydrocode CTH was used for a series of high-resolution simulations (50 cells per projectile radius) with varying angle of impact. Simulations were carried out for impacts at 90, 60, 45, 30, and 15° from the horizontal, while keeping projectile size (5 km in radius), type (dunite), and impact velocity (20 km/s) constant. The three-dimensional hydrocode simulations presented here show that in oblique impacts the distribution of shock pressure inside the projectile (and in the target as well) is highly complex, possessing only bilateral symmetry, even for a spherical projectile. Available experimental data suggest that only the vertical component of the impact velocity plays a role in an impact. If this were correct, simple theoretical considerations indicate that shock pressure, temperature, and energy would depend on sin2θ, where θ is the angle of impact (measured from the horizontal). However, our numerical simulations show that the mean shock pressure in the projectile is better fit by a sin θ dependence, whereas shock temperature and energy depend on sin3/2 θ. This demonstrates that in impact events the shock wave is the result of complex processes that cannot be described by simple empirical rules. The mass of shock melt or vapor in the projectile decreases drastically for low impact angles as a result of the weakening of the shock for decreasing impact angles. In particular, for asteroidal impacts the amount of projectile vaporized is always limited to a small fraction of the projectile mass. In cometary impacts, however, most of the projectile is vaporized even at low impact angles. In the oblique impact simulations a large fraction of the projectile material retains a net downrange motion. In agreement with experimental work, the simulations show that for low impact angles (30 and 15°), a downrange focusing of projectile material occurs, and a significant amount of it travels at velocities larger than the escape velocity of Earth.
A Conjecture about hadrons

Abstract We conjecture that in the chiral limit of QCD the spectrum of hadrons is comprised of decoupled, reducible chiral multiplets. A simple rule is developed which identifies the chiral representations filled out by the ground-state hadrons. Our arguments are based on the algebraic structure of superconvergence relations derived by Weinberg from the high-energy behavior of pion–hadron scattering amplitudes.
Application-specific worst case corners using response surfaces and statistical models

Integrated circuits (ICs) must be robust to manufacturing variations. Circuit simulation at a set of worst case corners is a computationally efficient method for verifying the robustness of a design. This paper presents a new statistical methodology to determine the worst case corners for a set of circuit performances. The proposed methodology first estimates response surfaces for circuit performances as quadratic functions of the process parameters with known statistical distributions. These response surfaces are then used to extract the worst case corners in the process parameter space as the points where the circuit performances are at their minimum/maximum values corresponding to a specified tolerance level. Corners in the process parameter space close to each other are clustered to reduce their number, which reduces the number of simulations required for design verification. The novel concept of a relaxation coefficient to ensure that the corners capture the minimum/maximum values of all the circuit performances at the desired tolerance level is also introduced. The corners are realistic since they are derived from the multivariate statistical distribution of the process parameters at the desired tolerance level. The methodology is demonstrated with examples showing extraction of corners from digital standard cells and also the corners for analog/radio frequency (RF) blocks found in typical communication ICs.
Development of LED lamps for airfield approach lighting systems

The Medium Intensity Approach Lighting System (MALSR) in use today at many airports throughout the United States employs many incandescent spot lamps. These lamps are relatively high wattage and, because of their relatively short life, require continual maintenance. Light emitting diodes (LEDs) have matured to the point that they can be considered to replace the inefficient incandescent lamps, especially when the latter are used with color filters. Under a Federal Aviation Administration (FAA) contract, Lighting Innovations Corporation (LIC) has developed LED based green runway threshold lamps for use in the MALSR. They already have been tested under flight conditions and are scheduled for full operational testing at several airports throughout the country. This paper addresses the advantages of LEDs over incandescents in this and other airfield lighting applications. Photometric, radiometric and spectral quantities are discussed, as are electrical, thermal and mechanical aspects of the project.
XPS study of CaO in sodium silicate glass

This paper shows that CaO added to silicate glasses behaves much like Na/sub 2/O in converting bridging oxygen sites to nonbridging sites. Good correspondence with model predictions was obtained but deviations were still sufficiently large to warrant attention. We speculate that some CaO may remain unreacted or that small-scale phase separation may occur. XPS core level shifts were monitored and possible charge-transfer effects were considered. Preliminary theoretical calculations utilizing a molecular-cluster approach were presented. XPS spectra for various glass compositions were simulated by appropriately combining local densities of state calculated for individual atoms. Dominant spectral features observed experimentally were found in the simulations. In conjunction with experiments, more carefully refined calculations will be subsequently examined. 7 figures.
Topological matter, integrable models and fusion rings

Abstract We show how topological G k /G k models can be embedded into the topological matter models that are obtained by perturbing the twisted N = 2 supersymmetric, hermitian symmetric, coset models. In particular, this leads to an embedding of the fusion ring of G as a sub-ring of the perturbed, chiral primary ring. The perturbation of the twisted N = 2 model that leads to the fusion ring is also shown to lead to an integrable N = 2 supersymmetric field theory when the untwisted N = 2 superconformal field theory is perturbed by the same operator and its hermitian conjugate.
Characterizations of Antimony Tri‐Sulfide Chemically Deposited with Silicotungstic Acid

A new chemical deposition method has been developed to prepare photoconducting n-Sb 2 S 3 thin polycrystalline films. The solution composition of the deposition bath was 0.025M potassium antimonyl tartarate, 0.4M triethanolamine, 0.025M thioacetamide, and 5×10 -7 M silicotungstic acid (STA), respectively. The as-deposited and the annealed films were characterized through x-ray diffraction, neutron activation analysis, and the optical absorption investigations. The photoelectrochemical performances of these films were examined
Intense neutrino beams and leptonic CP violation

Effects of the Leptonic CP violating phase, {delta}, on 3 generation neutrino oscillation rates and asymmetries are discussed. A figure of merit argument is used to show that our ability to measure the phase 6 is rather insensitive to the value of {theta}{sub 13} (for sin{sup 2} 2{theta}{sub 13} {approx}> 0.01) as well as the detector distance (for very long oscillation baselines). Using a study of {nu}{sub {mu}} {yields} {nu}{sub e} oscillations for BNL-Homestake (2540 km) we show that a conventional horn focused wide band neutrino beam generated by an intense 1-2 MW proton source combined with a very large water Cherenkov detector (250-500 kton) should be able to determine {delta} to about {+-}15{sup o} in 5 x 10{sup 7} sec. of running. In addition, such an effort would also measure the other oscillation parameters ({theta}{sub ij}, {Delta}m{sub ij}{sup 2}) with high precision. Similar findings apply to a Fermilab-Homestake (1280 km) baseline. We also briefly discuss features of Superbeams, Neutrino Factories and Beta-Beams.
BeTe/Si heterostructures for MIS and quantum device applications

The fabrication of silicon-based quantum devices and advanced buried-gate MIS transistors and circuits may require the development of an epitaxial insulating material that is lattice matched to silicon and also bonds with it to minimize interface states. We report the results of a search for new materials based on earlier partial successes with ZnS/Si. This work has identified beryllium chalcogenides as candidates with high stacking-fault energies for defect suppression. Initial growth and characterization experiments on BeTe/Si, a lattice mismatched system, bear out the theoretical predictions, and result in high-quality insulating films with >1 MV cm-1 breakdown fields. These experiments strongly suggest that lattice-matched BeSe0.45Te0.55 will be an even more suitable material.
A global assessment of deep-sea basalt sites for carbon sequestration

Abstract Deep-sea basalt aquifers have been identified for geological CO 2 sequestration in worldwide locations and offer vast reservoir capacities, permanent geochemical trapping potential, and other deep-sea protections that significantly reduce the risk of post- injection leakage. Using site-specific criteria, we target basalt aquifers along seismic and aseismic oceanic ridges, and calculate the injection volume potential for each. Results indicate that these aquifers occur in many oceans and could sequester 2.3–11.5 Tt-C along seismic ridges and 5.9–29.6 Tt-C along aseismic ridges. The enormous size of these potential reservoirs warrants further research and pilot experiments in each geographic setting.
Envelopes for Flight Through Stochastic Gusts

probability, that a steady ight state can be maintained when stochastic wind gusts act upon an airplane. First we linearize the airplane dynamic equations and present them as a linear time invariant system with the airplane’s velocity and angular velocity as the state and gust velocity as the input. We then treat the gust velocity as a stationary random process and append the dynamics of a coloring lter to the linearized airplane equations so that the input is Gaussian white noise. We analyze the eect of the noise on the airplane’s dynamics, using the resulting equations to quantify the eects of stochastic wind gusts on an airplane’s steady ight envelope. During the analysis we introduce the notion of stationary ight and a stationary ight envelope to guarantee, within a specied probability, steady ight under such conditions. We also present a numerical example of a general aviation aircraft in steady level ight through moderate turbulence. In the example, the airplane’s cruise speed uctuates with a variance of 1.2 m 2 /s 2 and we show examples of stationary ight envelopes for this case.
Gauss's law, gauge invariance, and long-range forces in QCD

Abstract We use a unitary operator constructed in earlier work to transform the Hamiltonian for QCD in the temporal ( A 0 = 0) gauge into a representation in which the quark field is gauge-invariant, and its elementary excitations - quark and antiquark creation and annihilation operators - implement Gauss's law. In that representation, the interactions between gauge-dependent parts of the gauge field and the spinor (quark) field have been transformed away and replaced by long-range non-local interactions of quark color charge densities. These long-range interactions connect SU(3) color charge densities through an infinite chain of gauge-invariant gauge fields either to other SU(3) color charge densities, or to a gluon “anchor”. We discuss possible implications of this formalism for low-energy processes, including confinement of quarks that are not in color singlet configurations.
Iterative approximate byzantine consensus in arbitrary directed graphs

This paper proves a necessary and sufficient condition for the existence of iterative, algorithms that achieve approximate Byzantine consensus in arbitrary directed graphs, where each directed edge represents a communication channel between a pair of nodes. The class of iterative algorithms considered in this paper ensures that, after each iteration of the algorithm, the state of each fault-free node remains in the convex hull of the states of the fault-free nodes at the end of the previous iteration. The following convergence requirement is imposed: for any e > 0, after a sufficiently large number of iterations, the states of the fault-free nodes are guaranteed to be within e of each other. To the best of our knowledge, tight necessary and sufficient conditions for the existence of such iterative consensus algorithms in synchronous arbitrary point-to-point networks in presence of Byzantine faults, have not been developed previously. The methodology and results presented in this paper can also be extended to asynchronous systems.
Enantio- and Diastereoselective Catalytic Carboalumination of 1-Alkenes and α,ω-Dienes with Cationic Zirconocenes: Scope and Mechanism

Bis(pentamethylcyclopentadienyl) dimethylzirconium (Cp*2ZrMe2) and bis(1-(−)-neomenthylindenyl) dimethylzirconium ((NMIn)2ZrMe2) upon activation by tris(pentafluorophenyl)borane are efficient catalysts for the carboalumination of a variety of 1-alkenes and nonconjugated dienes. The organoalane products can be oxidized to alcohol products, which are isolated in 50−90% yield. (NMIn)2ZrMe2 carboaluminates 1-alkenes and dienes with moderate (55−65%) enantioselectivities. In contrast, ethylenebis(tetrahydroindenyl) dimethylzirconium ((EBTHI)ZrMe2) and related zirconocenes give low activities and selectivities in the carboalumination reaction. Study of the interaction of zirconocene methyl cations with trimethylaluminum by 1H NMR shows that [(EBTHI)ZrMe][MeB(C6F5)3] forms a stable bis(μ-methyl) aluminum adduct. Zirconocene methyl cations derived from Cp*2ZrMe2 and (NMIn)2ZrMe2 react slowly with large excesses of trimethylaluminum to form weakly bound trimethylaluminum adducts. The difference in trimethylaluminu...
Standard-state Gibbs energies of the BCC, HCP, and CCP structures of metals

Abstract It is common practice to use the stable crystal form of a metal as the standard state for solid solutions and to use the pure liquid as the standard state for liquid solutions. When the deviations from Raoult's Law are small, this is usually the most convenient procedure even when the solid solution has a different crystal structure. However, when the deviations are substantial and one is interested in relatively dilute solutions, it is more convenient to use a standard state with the same crystal structure as the solid solution. Thermodynamic data are presented for the pure standard states (Raoult's Law standard states) for stable and metastable structures and for the Henry's Law standard states with the structure of the solid solution. Henry's Law standard states are also given for the liquid.
Quantitative phase imaging via Fourier ptychographic microscopy

Fourier ptychographic microscopy (FPM) is a recently developed imaging modality that uses angularly varying illumination to extend a system’s performance beyond the limit defined by its optical components. The FPM technique applies a novel phase-retrieval procedure to achieve resolution enhancement and complex image recovery. In this Letter, we compare FPM data to theoretical prediction and phase-shifting digital holography measurement to show that its acquired phase maps are quantitative and artifact-free. We additionally explore the relationship between the achievable spatial and optical thickness resolution offered by a reconstructed FPM phase image. We conclude by demonstrating enhanced visualization and the collection of otherwise unobservable sample information using FPM’s quantitative phase.
Scope and Mechanistic Study of the Ruthenium-Catalyzed ortho-C−H Bond Activation and Cyclization Reactions of Arylamines with Terminal Alkynes

The cationic ruthenium hydride complex [(PCy(3))(2)(CO)(CH(3)CN)(2)RuH](+)BF(4)(-) was found to be a highly effective catalyst for the C-H bond activation reaction of arylamines and terminal alkynes. The regioselective catalytic synthesis of substituted quinoline and quinoxaline derivatives was achieved from the ortho-C-H bond activation reaction of arylamines and terminal alkynes by using the catalyst Ru(3)(CO)(12)/HBF(4).OEt(2). The normal isotope effect (k(CH)/k(CD) = 2.5) was observed for the reaction of C(6)H(5)NH(2) and C(6)D(5)NH(2) with propyne. A highly negative Hammett value (rho = -4.4) was obtained from the correlation of the relative rates from a series of meta-substituted anilines, m-XC(6)H(4)NH(2), with sigma(p) in the presence of Ru(3)(CO)(12)/HBF(4).OEt(2) (3 mol % Ru, 1:3 molar ratio). The deuterium labeling studies from the reactions of both indoline and acyclic arylamines with DCCPh showed that the alkyne C-H bond activation step is reversible. The crossover experiment from the reaction of 1-(2-amino-1-phenyl)pyrrole with DCCPh and HCCC(6)H(4)-p-OMe led to preferential deuterium incorporation to the phenyl-substituted quinoline product. A mechanism involving rate-determining ortho-C-H bond activation and intramolecular C-N bond formation steps via an unsaturated cationic ruthenium acetylide complex has been proposed.
Credible autocoding of fault detection observers

We present a domain specific process to enable the verification of observer-based fault detection software. Observer-based fault detection systems, like control systems, yield invariant properties of quadratic types. These quadratic invariants express both safety properties of the software, such as the boundedness of the states, and correctness properties, such as the absence of false alarms from the fault detector. We seek to leverage these quadratic invariants, in an automated way, for the formal verification of the fault detection software. The approach, named the credible autocoding framework, can be characterized as autocoding with proofs. The process starts with the fault detector model, along with its safety and correctness properties, all expressed formally in a synchronous modeling environment such as Simulink. The model is then transformed by a prototype credible autocoder into both code and analyzable annotations for the code. We demonstrate the credible autocoding process on a running example of an output observer fault detector for a 3 degree-of-freedom helicopter control system.
Boolean satisfiability using noise based logic

Noise-based Logic (NBL) is a probabilistic logic system which can be used to simultaneously apply a superposition of arbitrarily many input vectors to a SAT instance. Using this property, we can determine whether an instance is SAT in a single operation. A satisfying solution can be found by iteratively performing SAT checks up to n times, where n is the number of variables in the SAT instance. In this paper, we formulate NBL-based SAT, and discuss its scalability. The NBL-based SAT engine has been simulated in software for validation purposes, although the focus of the paper is on the theory of NBL-based SAT.
Description, prescription and the choice of discount rates

Abstract The choice of discount rates is a key issue in the analysis of long-term societal issues, in particular environmental issues such as climate change. Approaches to choosing discount rates are generally placed into two categories: the descriptive approach and the prescriptive approach. The descriptive approach is often justified on grounds that it uses a description of how society discounts instead of having analysts impose their own discounting views on society. This paper analyzes the common forms of the descriptive and prescriptive approaches and finds that, in contrast with customary thinking, both forms are equally descriptive and prescriptive. The prescriptions concern who has standing (i.e. who is included) in society, how the views of these individuals are measured, and how the measurements are aggregated. Such prescriptions are necessary to choose from among the many possible descriptions of how society discounts. The descriptions are the measurements made given a choice of measurement technique. Thus, the labels “descriptive approach” and “prescriptive approach” are deeply misleading, as analysts cannot avoid imposing their own views on society.
Hydrogen/air combustion calculations - The chemical basis of efficiency in hypersonic flows

The combustion of premixed hydrogen and air is investigated under conditions relevant to scramjet propulsion. A comprehensive hydrogen/air kinetics mechanism is used that suffices to model combustion in air, including HO 2 and H 2 O 2 chemistry but excluding carbon compounds. The primary objective is to understand the chemical inefficiencies of combustion in hypersonic flows. In this regard, the chemistry in streamlines within a hypothetical hypersonic combustor is investigated. Computational results based on equilibrium assumptions and finite-rate kinetics are compared
Hadamard tensors and lower bounds on multiparty communication complexity

We develop a new method for estimating the discrepancy of tensors associated with multiparty communication problems in the "Number on the Forehead" model of Chandra, Furst, and Lipton. We define an analog of the Hadamard property of matrices for tensors in multiple dimensions and show that any k-party communication problem represented by a Hadamard tensor must have ?(n/2 k ) multiparty communication complexity. We also exhibit constructions of Hadamard tensors. This allows us to obtain ?(n/2 k ) lower bounds on multiparty communication complexity for a new class of explicitly defined Boolean functions.
Self indexing of neural memories

Abstract It is shown that the property of self-indexing allows stable memories to be generated by very short subsequences. This defines a mechanism for sequential associative memory and for the sequential generation of a number of states. By using generator sequences longer than the minimum length the mechanism can also correct errors.
Dissipation at tidal and seismic frequencies in a melt-free Moon

[1] We calculate viscoelastic dissipation in the Moon using a rheological (extended Burgers) model based on laboratory deformation of melt-free polycrystalline olivine. Lunar temperature structures are calculated assuming steady state conduction with variable internal heat production and core heat flux. Successful models can reproduce the dissipation factor (Q) measured at both tidal and seismic frequencies, and the tidal Love numbers h2 and k2, without requiring any mantle melting. However, the frequency-dependence of our modelQat tidal periods has the opposite sign to that observed. Using the apparently unrelaxed nature of the core-mantle boundary (CMB), the best fit models require mantle grain sizes of ∼1 cm and CMB temperatures of ≈1700 K. If melt or volatiles are present, the lunar temperature structure must be colder than our melt-free models. We estimate a present-day mantle heat production rate of 9–10 nWm−3, suggesting that roughly half of the Moon's radiogenic elements are in the crust.
NON-LTE MODELS AND THEORETICAL SPECTRA OF ACCRETION DISKS IN ACTIVE GALACTIC NUCLEI. III. INTEGRATED SPECTRA FOR HYDROGEN-HELIUM DISKS

We have constructed a grid of non-LTE disk models for a wide range of values of black hole mass and mass accretion rate, for several values of the viscosity parameter a, and for two extreme values of the black hole spin: the maximum-rotation Kerr black hole, and the Schwarzschild (nonrotating) black hole. Our procedure calculates self-consistently the vertical structure of all disk annuli together with the radiation —eld, without any approximations imposed on the optical thickness of the disk, and without any ad hoc approximations to the behavior of the radiation intensity. The total spectrum of a disk is computed by summing the spectra of the individual annuli, taking into account the general relativistic transfer function. The grid covers nine values of the black hole mass between M \ 1/8 ) 109 and 32 ) 109 with a M _ twofold increase of mass for each subsequent value; and eleven values of the mass accretion rate, each a power of 2 times 1 yr~1. The highest value of the accretion rate corresponds to the total luminosity M _ We show the vertical structure of individual annuli within the set of accretion disk models, L /L Edd B 0.3. along with their local emergent —ux, and discuss the internal physical self-consistency of the models. We then present the full disk-integrated spectra and discuss a number of observationally interesting proper- ties of the models, such as optical/ultraviolet colors, the behavior of the hydrogen Lyman limit region, polarization, and the number of ionizing photons. Our calculations are far from de—nitive in terms of the input physics, but generally we —nd that our models exhibit rather red optical/UV colors. Flux discon- tinuities in the region of the hydrogen Lyman limit are only present in cool, low-luminosity models, while hotter models exhibit blueshifted changes in spectral slope. Subject headings: accretion, accretion disksgalaxies: activegalaxies: nuclei