cssi/SciSciGPT-SciSciNet huggingface dataset:
Measurements of the dynamical behavior of projectiles over long flight paths

20 Moyer, C. B. and Rindal, R. A., "Finite Difference Solution for the In-Depth Response of Charring Materials Considering Surface Chemical and Energy Balances," Final Rept. 66-7, Pt. II, March 1967, Vidya Div., Itek Corp., Palo Alto, Calif. 21 Mathieu, R. D., "Mechanical Spallation of Charring Ablators in Hyperthermal Environments," AIAA Journal, Vol. 2, No. 9, Sept. 1964, pp. 1621-1627. 22 Bishop, W. M. and DiCristina, V., "A Prediction Technique for Ablative Material Performance Under High Shear Re-Entry Conditions," AIAA Journal, Vol. 6, No. 1, Jan. 1968, pp. 59-63. 23 Kratsch, K. M. et al., "Graphite Ablation in High-Pressure Environments," AIAA Paper 68-1153, Williamsburg, Va., 1968. 24 McVey, D. F., Auerbach, I., and McBride, D. D., "Some Observations on the Influence of Graphite Microstructure on Ablation Performance," AIAA Paper 70-155, New York, 1970. 25 Schneider, P. J., Dolton, T. A., and Reed, G. W., "Mechanical Erosion of Charring Ablators in Ground-Test Reentry Environments," AIAA Journal, Vol. 6, No. 1, Jan. 1968, pp. 64-72.
U(2) flavor physics without U(2) symmetry

The authors present a model of fermion masses based on a minimal, non-Abelian discrete symmetry that reproduces the Yukawa matrices usually associated with U(2) theories of flavor. Mass and mixing angle relations that follow from the simple form of the quark and charged lepton Yukawa textures are therefore common to both theories. They show that the differing representation structure of the horizontal symmetry allows for new solutions to the solar and atmospheric neutrino problems that do not involve modification of the original charged fermion Yukawa textures, or the introduction of sterile neutrinos.
The effect of copper content and heat treatment on the hydrogen embrittlement of 7050-type alloys

Abstract The effect of copper content (0.01 and 2.1%) and microstructure on the intrinsic hydrogen embrittlement susceptibility of unl nercially-processed AI6Zn2MgXCu alloys was investigated. (The alloy with 2.1 Cu corresponds to 7059). Hydrogen was introduced into the alloys using cathodic charging, both with and without concurrent plastic straining. The copper-free alloy in both the under-aged and peak-aged conditions was embrittled by hydrogen and the effect was enhanced by concurrent plastic strain. The copper-containing alloy (7050) was susceptible to hydrogen embrittlement when under-aged, but once the peak-strength microstructure had been developed, the alloy in the longitudinal direction showed no embrittlement even under severe hydrogen-entry conditions. Similar beneficial effects have been reported for copper additions in imparting resistance to humid air and stress-corrosion cracking for high strength AI-Zn-Mg alloys, and the results are discussed with emphasis on the parallel nature of the phenomena of stress-corrosion cracking and hydrogen embrittlement.
Approximate Storage in Solid-State Memories

Memories today expose an all-or-nothing correctness model that incurs significant costs in performance, energy, area, and design complexity. But not all applications need high-precision storage for all of their data structures all of the time. This article proposes mechanisms that enable applications to store data approximately and shows that doing so can improve the performance, lifetime, or density of solid-state memories. We propose two mechanisms. The first allows errors in multilevel cells by reducing the number of programming pulses used to write them. The second mechanism mitigates wear-out failures and extends memory endurance by mapping approximate data onto blocks that have exhausted their hardware error correction resources. Simulations show that reduced-precision writes in multilevel phase-change memory cells can be 1.7 × faster on average and using failed blocks can improve array lifetime by 23p on average with quality loss under 10p.
Summarizing large document sets using concept-based clustering

This paper describes our multi-document summarizer XDoX designed to summarize large sets of documents (50--500). These documents are typically obtained from routing or filtering systems run against a continuous stream of data, such as a newswire. XDoX identifies the most salient or often-repeated themes within the set and composes an extraction summary reflecting these main themes. The summarizer uses a unique n-gram scoring method to give greater importance to clusters of passages that have significant common phrases. Our methods are robust, topic-independent, and easily extensible to multilingual applications. We show examples of summaries obtained in our tests as well as from our participation in the first Document Understanding Conference (DUC).
Low-Background Monitoring Cameras for the Daya Bay Antineutrino Detectors

The Daya Bay Reactor Neutrino Experiment is designed to measure the neutrino mixing angle θ13 to world-leading precision. The experiment deploys identical antineutrino detectors at distances of 400-1900 m from six reactors in Daya Bay, China. Each detector incorporates two general-purpose monitoring cameras to ensure their safe construction, transportation and operation. The cameras must meet usage goals while satisfying stringent constraints on radioactivity, materials compatibility, interference and reliability. This article describes the system design, integration, operation and performance.
Enhanced inelastic scattering rates of cold atomic chromium

Inelastic scattering rates for magnetically trapped atomic chromium are determined for temperatures of 2 mK and higher. It is found that the rate is very large (2×10-9 cm3/s at 4 mK) and has a strong dependence on temperature. The origin of this structure in the inelastic rate remains for theoretical explanation. These experiments show that, even with bad inelastic rates, the efficacy of buffer-gas loading in producing large numbers of cold atoms is quite good.
The First FIRST Gravitationally Lensed Quasar: FBQ 0951+2635*

The V = 16.9 quasar FBQ 0951+2635 at redshift z = 1.24 appears double on CCD exposures taken in subarcsecond seeing. The two objects are separated by 11 and differ in brightness by 0.9 mag. VLA observations show the radio source to be double with the same separation and position angle. Spectra taken with the Keck II Telescope show the two components to have nearly identical emission-line spectra, but with somewhat different absorption-line systems. Subtraction of two stellar point-spread functions from the pair of components consistently leaves a residual object. Depending upon whether this third object is extended or a point source, it may be as much as 1/10 or as little as 1/100 as bright as the brighter QSO component. The observations leave little doubt that the two brighter objects are gravitationally lensed images of the same quasar. The third object might be either the lensing galaxy or a third image of the quasar, but both interpretations have serious shortcomings.
Free-Surface Vibrations of a Magnetic Liquid

Magnetic fluid sloshing in solenoidal magnetic field, describing fluid free surface waves similarity to ordinary liquid waves in reduced gravity field
Applications of extreme anisotropy of two-dimensional photonic structures

Upper bands of 2-D photonic crystals are shown to exhibit extreme anisotropy even near gamma-point: (a) isofrequency contours are hyperbolic instead of circular; (b) direction-dependent angle between group and phase velocities. Novel beam splitters and mirrors are proposed
Globalization and the 'confidence game'

Abstract We show that governments in developing countries have an incentive to play the “ confidence game ” — wherein the need to win the confidence of the international capital market ‘can actually prevent a country from following otherwise sensible policies and force it to follow policies that it would normally consider perverse’. This incentive arises because of a combination of a ‘conformity bias’ and ‘good news bias’ in governmental decision making in an open economy, which results in inefficient outcomes which increases rather than decreases the threat of devaluation. While institutions that encourage greater transparency and the public revelation of information, may often mitigate this inefficiency, on some occasions increased transparency may even exacerbate the inefficiency.
Modeling coupled thermal–hydrological–chemical processes in the unsaturated fractured rock of Yucca Mountain, Nevada: Heterogeneity and seepage

An understanding of processes affecting seepage intoemplacement tunnels is needed for correctly predicting the performance ofunderground radioactive waste repositories. It has been previouslyestimated that the capillary and vaporization barriers in the unsaturatedfractured rock of Yucca Mountain are enough to prevent seepage underpresent day infiltration conditions. It has also been thought that asubstantially elevated infiltration flux will be required to causeseepage after the thermal period is over. While coupledthermal-hydrological-chemical (THC) changes in Yucca Mountain host rockdue to repository heating has been previously investigated, those THCmodels did not incorporate elements of the seepage model. In this paper,we combine the THC processes in unsaturated fractured rock with theprocesses affecting seepage. We observe that the THC processes alter thehydrological properties of the fractured rock through mineralprecipitation and dissolution. We show that such alteration in thehydrological properties of the rock often leads to local flow channeling.We conclude that such local flow channeling may result in seepage undercertain conditions, even with nonelevated infiltrationfluxes.
SODOS: A software documentation support environment — Its use

A description is given of a computerized environment, SODOS (Software Documentation Support), which supports the definition and manipulation of documents used in developing software. An object-oriented environment is used as a basis for the SODOS interface. SODOS is built around a software life-cycle model that structures all access to the documents stored in the environment. This model supports software documentation independently of any fixed methodology that the developers may be using. The main advantage of the system is that it permits traceability through each phase of the life cycle, thus facilitating the test and maintenance phases. The effort involved in learning and using SODOS is simplified by a sophisticated, user-friendly interface.
Elastic charge form factors for K mesons

Abstract The elastic charge form factors for the charged K+ and neutral K0 are presented. The model employed makes use of solutions of the coupled Bethe-Salpeter and Schwinger-Dyson equations. This covariant model provides good predictions for the pion's elastic charge and transition form factor, and here we extend the model to include strange quarks. The results for the kaon are in good agreement with the available data. This model is partially motivated by the expectation of precision data from CEBAF approved experiment E-93-018. The non vanishing K0 form factor is due to the mass difference between the strange and down quarks.
PHYSICAL PROPERTIES OF THE NARROW-LINE REGION OF LOW-MASS ACTIVE GALAXIES

We present spectroscopic observations of 27 active galactic nuclei (AGNs) with some of the lowest black hole (BH) masses known. We use the high spectral resolution and small aperture of our Keck data, taken with the Echellette Spectrograph and Imager, to isolate the narrow-line regions (NLRs) of these low-mass BHs. We investigate their emission-line properties and compare them with those of AGNs with higher-mass BHs. While we are unable to determine absolute metallicities, some of our objects plausibly represent examples of the low-metallicity AGNs described by Groves et al., based on their [N II]/Hα ratios and their consistency with the Kewley & Ellison mass-metallicity relation. We find tentative evidence for steeper far-UV spectral slopes in lower-mass systems. Overall, NLR emission lines in these low-mass AGNs exhibit trends similar to those seen in AGNs with higher-mass BHs, such as increasing blueshifts and broadening with increasing ionization potential. Additionally, we see evidence of an intermediate-line region whose intensity correlates with L/L Edd, as seen in higher-mass AGNs. We highlight the interesting trend that, at least in these low-mass AGNs, the [O III] equivalent width (EW) is highest in symmetric NLR lines with no blue wing. This trend of increasing [O III] EW with line symmetry could be explained by a high covering factor of lower-ionization gas in the NLR. In general, low-mass AGNs preserve many well-known trends in the structure of the NLR, while exhibiting steeper ionizing continuum slopes and somewhat lower gas-phase metallicities.
Three-Dimensional Simulations Of An XUV Free-Electron Laser

Operation of free-electron lasers at long optical wavelengths (≥600 nm) has now been successfully demonstrated at several laboratories. To operate a free-electron laser at shorter wavelengths imposes constraints on the brightness of the electron beam which are difficult to achieve. Until recently, it was perceived that only an electron storage ring could satisfy these beam requirements. However, our previous 1-D theoretical calculations revealed that modest improvements in the emittance available from rf-linear accelerators would be sufficient to allow operation of an FEL in the XUV spectral range. We shall present new theoretical results for the design of a linac-driven XUV FEL derived from an improved simulation model. The model is fully three-dimensional in its treatment of the undulator magnetic field, the optical radiation field, and the motion of electrons in a finite-emittance beam. Furthermore, the model computes self-consistently the motion of the electrons and the amplification, diffraction, and the refraction of the light within the undulator magnet. Propagation of the optical beam and reflection at the mirrors of the optical resonator are incorporated in the model so that a complete laser oscillator solution can be generated. The computed performance parameters of a particular XUV FEL oscillator design will be compared with the output of synchrotron radiation sources.
Selenium becomes metallic in Ru-Se fuel cell catalysts: an EC-NMR and XPS investigation.

We report the results of an investigation of the interaction between Se and Ru in Ru−Se electrocatalysts showing high activity and methanol tolerance in the oxygen reduction reaction (ORR). The res...
Government Regulation of Competition in the Food Industry

The effect of antitrust laws on the food industry is examined in terms of enforecement patterns, competitive trends in the industry, and a comparison with experiences of other countries. Although the antitrust laws have focused on those firms that compete most successfully, it has helped to preserve competition among industries whose products have little differentiation. Several suggestions are made for making antitrust policies more effective, such as prompt public information about large firms through Federal chartering or some other means, more control of advertising through trademark licensing or cost ceilings on advertising for some products, alternatives to divestiture that will weaken conglomerate power by limiting mergers and activities, and broadening markets through electronic exchanges. 21 references.
Platinum-Catalyzed Tandem Indole Annulation/Arylation for the Synthesis of Diindolylmethanes and Indolo[3,2-b]carbazoles

Various diindolylmethanes were prepared from propargylic ethers and substituted indoles via a platinum-catalyzed tandem indole annulation/arylation cascade. The resulting diindolylmethanes could be converted to natural product malassezin by formylation or indolo[3,2-b]carbazoles by cyclization.
Hybrid Techniques Applied To Optimization Problems

A function dependent on the solution of a set of dif ferential equations containing adjustable parameters, can be minimized by systematic search procedures in parameter space. Such procedures can be imple mented by a hybrid system consisting of a general purpose analog computer and a digital expansion providing parallel logic building blocks. Program ming of such a system is illustrated for a simple search procedure in n parameters.
N-benzoylcarbamate cyclizations

Abstract The anion of an alcohol derived N-benzoylcarbamate may be used to deliver nitrogen intramolecularly to electrophilic centers. This allows the stereocontrolled synthesis of a variety of amino-alcohol and amino-diol derivatives.
Mod 2 homology of the stable spin mapping class group

Using the main result of Madsen and Weiss [MW], we compute the mod 2 homology of spin mapping class groups in the stable range. In earlier work [G] we computed the stable mod p homology of the oriented mapping class group, and the methods and results here are very similar. The forgetful map from the spin mapping class group to the oriented mapping class groups induces a homology isomorphism for odd p but for p=2 it is far from being an isomorphism. We include a general discussion of tangential structures on 2-manifolds and their mapping class groups and then specialise to spin structures.
Whittaker modules for generalized Weyl algebras

We investigate Whittaker modules for generalized Weyl algebras, a class of associative algebras which includes the quantum plane, Weyl algebras, the universal enveloping algebra of sl_2 and of Heisenberg Lie algebras, Smith's generalizations of U(sl_2), various quantum analogues of these algebras, and many others. We show that the Whittaker modules V = Aw of the generalized Weyl algebra A = R(phi,t) are in bijection with the phi-stable left ideals of R. We determine the annihilator Ann_A(w) of the cyclic generator w of V. We also describe the annihilator ideal Ann_A(V) under certain assumptions that hold for most of the examples mentioned above. As one special case, we recover Kostant's well-known results on Whittaker modules and their associated annihilators for U(sl_2).
Visual working memory for simple and complex visual stimuli

Does the magical number four characterize our visual working memory (VWM) capacity for all kinds of objects, or is the capacity of VWM inversely related to the perceptual complexity of those objects? To find out how perceptual complexity affects VWM, we used a change detection task to measure VWM capacity for six types of stimuli of different complexity: colors, letters, polygons, squiggles, cubes, and faces. We found that the estimated capacity decreased for more complex stimuli, suggesting that perceptual complexity was an important factor in determining VWM capacity. However, the considerable correlation between perceptual complexity and VWM capacity declined significantly if subjects were allowed to view the sample memory display longer. We conclude that when encoding limitations are minimized, perceptual complexity affects, but does not determine, VWM capacity.
Preferential detachment in broadcast signaling networks: Connectivity and cost trade-off

We consider a network of nodes distributed in physical space without physical links communicating through message broadcasting over specified distances. Typically, communication using smaller distances is desirable due to savings in energy or other resources. We introduce a network formation mechanism to enable reducing the distances while retaining connectivity. Nodes, which initially transmit signals at a prespecified maximum distance, subject links to preferential detachment by autonomously decreasing their transmission radii while satisfying conditions of zero communication loss and fixed maximum node-hopping distance for signaling. Applied to networks with various spatial topologies, we find cost reductions as high as 90% over networks that are restricted to have all nodes with equal transmission distance.
Trace anomalies and the string-inspired definition of quantum-mechanical path integrals in curved space

Abstract We consider quantum-mechanical path integrals for non-linear sigma models on a circle defined by the string-inspired method of Strassler, where one considers periodic quantum fluctuations about a center-of-mass coordinate. In this approach one finds incorrect answers for the local trace anomalies of the corresponding n-dimensional field theories in curved space. The quantum field theory approach to the quantum-mechanical path-integral, where fluctuations are not periodic but vanish at the endpoints, yields the correct answers. We explain these results by a detailed analysis of general coordinate invariance in both methods. Both approaches can be derived from the same operator expression and the integrated trace anomalies in both schemes agree. In the string-inspired method the integrands are not invariant under general coordinate transformations and one is therefore not permitted to use Riemann normal coordinates.
Performance Analysis for Brandt's Conclusive Entangling Probe

The Fuchs---Peres---Brandt (FPB) probe realizes the most powerful individual attack on Bennett-Brassard 1984 quantum key distribution by means of a single controlled-NOT gate in which Alice's transmitted qubit becomes the control-qubit input, Bob's received qubit is the control-qubit output, and Eve supplies the target-qubit input and measures the target-qubit output. The FPB probe uses the minimum-error-probability projective measurement for discriminating between the target-qubit output states that are perfectly correlated with Bob's sifted bit value when that bit is correctly received. This paper analyzes a recently proposed modification of the FPB attack in which Eve's projective measurement is replaced by a probability operator-valued measurement chosen to unambiguously discriminate between the same two target-qubit output states.
Sublinear-time parallel algorithms for matching and related problems

Abstract This paper presents the first sublinear-time deterministic parallel algorithms for bipartite matching and several related problems, including maximal node-disjoint paths, depth-first search, and flows in zero-one networks. Our results are based on a better understanding of the combinatorial structure of the above problems. which leads to new algorithmic techniques. In particular, we show how to use maximal matching to extend, in parallel, a current set of node-disjoint paths and how to take advantage of the parallelism that arises when a large number of nodes are "active" during an execution of a push-relabel network flow algorithm. We also show how to apply our techniques to design parallel algorithms for the weighted versions of the above problems. In particular, we present sublinear-time deterministic parallel algorithms for finding a minimum-weight bipartite matching and for finding a minimum-cost flow in a network with zero-one capacities, if the weights are polynomially bounded integers.
Technology Capital: The Price of Admission to the Growth Club

We assess long-run patterns of global agricultural productivity growth between 1970 and 2005 and examine the relationship between investments in technology capital and productivity. To measure agricultural total factor productivity (TFP) we employ a Solow-type growth accounting method to decompose output growth into input and TFP growth. For technology capital we construct two indexes reflecting national capacities in agricultural research and education-extension for 87 developing countries. We then correlate technology capital levels with long-term growth rates in agricultural TFP. Our findings show that global agricultural TFP growth as a whole accelerated since 1980, although performance was very uneven across developing countries. TFP growth rates were significantly influenced by technology capital. Marginal improvements to research capacity, given a minimal level of extension and schooling existed, were associated with faster TFP growth. However, marginal increases in extension-schooling without commensurate improvements in research capacity did not improve productivity performance.
ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS

We investigate rotational spin noise (referred to as timing noise) in non-accreting pulsars: millisecond pulsars, canonical pulsars, and magnetars. Particular attention is placed on quantifying the strength and non-stationarity of timing noise in millisecond pulsars because the long-term stability of these objects is required to detect nanohertz gravitational radiation. We show that a single scaling law is sufficient to characterize timing noise in millisecond and canonical pulsars while the same scaling law underestimates the levels of timing noise in magnetars. The scaling law, along with a detailed study of the millisecond pulsar B1937+21, leads us to conclude that timing noise is latent in most millisecond pulsars and will be measurable in many objects when better arrival time estimates are obtained over long data spans. The sensitivity of a pulsar timing array to gravitational radiation is strongly affected by any timing noise. We conclude that detection of proposed gravitational wave backgrounds will require the analysis of more objects than previously suggested over data spans that depend on the spectra of both the gravitational wave background and of the timing noise. It is imperative to find additional millisecond pulsars in current and future surveys in order to reduce the effects of timing noise.
Dehydration of Tetracycline

The dehydration of tetracycline at the C-5a-C-6 position as a function of acidity was investigated at various temperatures. The rate was first order with respect to tetracycline and with respect to [H+]. Rate constants and an activation energy are reported. Tetracycline was unstable in dilute acid.
Ego-centered networks and the ripple effect

Abstract Recent work has demonstrated that many networks have broad distributions of vertex degree. Here we show that this has a substantial impact on the shape of ego-centered networks and on concepts and methods based on ego-centered networks, such as snowball sampling and the “ripple effect”. In particular, we argue that one’s acquaintances, one’s immediate neighbors in the acquaintance network, are far from being a random sample of the population, and that this biases the numbers of neighbors two and more steps away. We demonstrate this concept using data on academic collaboration networks.
Rectangle-visibility representations of bipartite graphs

Abstract The paper considers representations of bipartite graphs as rectangle-visibility graphs , i.e., graphs whose vertices are rectangles in the plane, with adjacency determined by horizontal and vertical visibility. It is shown that, for p ⩽ q , K p , q has a representation with no rectangles having collinear sides if and only if p ⩽ 2 or p = 3 and q ⩽ 4. More generally, it is shown that K p , q is a rectangle-visibility graph if and only if p ⩽ 4. Finally, it is shown that every bipartite rectangle-visibility graph on n ⩾ 4 vertices has at most 4 n − 12 edges.
Solution stability and phase transition for two SDEs by a fixed time step integration scheme

Abstract The fixed time step integration method proposed in Grigoriu (2009) [2] is used to construct recurrence formulas for generating samples of processes X ( t ) satisfying stochastic differential equations (SDEs) with Gaussian (GWN) and Poisson white noise (PWN). Theoretical arguments and numerical examples are employed to show that the sequence of processes X n ( t ) defined by these recurrence formulas can be used to assess the stability of the trivial solution of SDEs with linear drift and diffusion coefficients driven by GWN and/or PWN and capture the phase transition phenomenon exhibited by the state of a randomized Verhulst model for population growth.
MMCs and PPCs as constructs of curvature regions for form feature determination

Shape feature information about a part is required to analyze the part for downstream issues such as manufacturability and assemblability. One method of obtaining the feature information is feature recognition from the geometric model. The current approach called Curvature Region (CR) approach for feature determination from solid models categorizes features into two primitive shape classes: protrusions and depressions. In the first step, these primitive shape classes are recognized from the solid model. In the next step, the primitive shape classes are matched with feature definitions to obtain features.
Off-critical lattice analogues of N = 2 supersymmetric quantum integrable models☆

Abstract We obtain off-critical (elliptic) Boltzmann weights for lattice models whose continuum limits correspond to massive, N = 2 supersymmetric, quantum integrable field theories. We also compute the free energies of these models and show that they are analytic in the region of parameter space where we believe that the supersymmetry is unbroken. While the supersymmetry is not directly realized on the lattice, there is still a very close connection between the models described here and topological lattice models. A simple example is discussed in detail and some corner transfer matrix computations are also presented.
Application of tissue-marking ink to prostate biopsy specimens.

BACKGROUND When sextant prostate biopsy specimens are performed, noting the location from which cancer-containing cores were taken aids in treatment planning. However, many institutions include several cores in a single container, to cut costs. We have tried several methods of ink application and combining ink-labeled biopsy specimens into fewer containers with the goal of maintaining information regarding location while minimizing the expense. METHODS Several approaches to the application of tissue-marking ink to biopsy cores, core-preparation methods, color combinations, and numbers of cores in each container were assessed. RESULTS The ink adheres well to dry cores, but these cores often exhibit dehydration artifact. Placing the cores on a wet sponge avoids dehydration but causes ink spread. Excessive ink application occurs with eyedroppers and syringes but is avoided by touching each core with an ink-moistened cotton swab. Application of 1% acetic acid to the inked core promotes congealing of the ink onto the tissue. Yellow, orange, and red ink are more difficult to distinguish than blue, black, or green. Deciphering distinct cores when three or more cores are combined is difficult, especially if cores are fragmented. CONCLUSIONS With our current protocol, all biopsy specimens are placed on separate moistened gauze sponges. Specimens from the right side of the prostate are marked by green ink, and those from the left side are marked by black ink with a cotton swab. After applying 1% acetic acid to each core, the left and right cores from each location are placed in a single container. This method curbs pathology expenses and maintains tumor location information. Prostate 50: 247–251, 2002. © Wiley-Liss, Inc.
Equations for Lower Bounds on Border Rank

We present new methods for determining polynomials in the ideal of the variety of bilinear maps of border rank at most r. We apply these methods to several cases including the case r=6 in the space of bilinear maps . This space of bilinear maps includes the matrix multiplication operator M 2 for 2×2 matrices. We show that these newly obtained polynomials do not vanish on the matrix multiplication operator M 2, which gives a new proof that the border rank of the multiplication of 2×2 matrices is seven. Other examples are considered along with an explanation of how to implement the methods.
Bidentate ligands on osmium(VI) nitrido complexes control intracellular targeting and cell death pathways.

The cellular response evoked by antiproliferating osmium(VI) nitrido compounds of general formula OsN(N^N)Cl3 (N^N = 2,2′-bipyridine 1, 1,10-phenanthroline 2, 3,4,7,8-tetramethyl-1,10-phenanthroline 3, or 4,7-diphenyl-1,10-phenanthroline 4) can be tuned by subtle ligand modifications. Complex 2 induces DNA damage, resulting in activation of the p53 pathway, cell cycle arrest at the G2/M phase, and caspase-dependent apoptotic cell death. In contrast, 4 evokes endoplasmic reticulum (ER) stress leading to the upregulation of proteins of the unfolded protein response pathway, increase in ER size, and p53-independent apoptotic cell death. To the best of our knowledge, 4 is the first osmium compound to induce ER stress in cancer cells.
Heterotic-heterotic string duality and multiple K3 fibrations

Abstract A type IIA string compactified on a Calabi-Yau manifold which admits a K3 fibration is believed to be equivalent to a heterotic string in four dimensions. We study cases where a Calabi-Yau manifold can have more than one such fibration leading to equivalences between perturbatively inequivalent heterotic strings. This allows an analysis of an example in six dimensions due to Duff, Minasian and Witten and enables us to go some way to prove a conjecture by Kachru and Vafa. The interplay between gauge groups which arise perturbatively and nonperturbatively is seen clearly in this example. As an extreme case we discuss a Calabi-Yau manifold which admits an infinite number of K3 fibrations leading to infinite set of equivalent heterotic strings.
Density-functional study of the U-Zr system

Abstract Density-functional formalism is applied to study the phase equilibria in the U–Zr system. The obtained ground-state properties of the γ (bcc) and δ (C32) phases are in good agreement with experimental data. The decomposition curve for the γ -based U–Zr solutions is calculated. Our calculations confirm that experimentally observed “partial” ordering of the alloy components in the δ -UZr 2 (AlB 2 ) phase, in which Zr atoms occupy the “Al” position and the two “B” sites are randomly shared by the U and Zr atoms, is the most energetically favorable within the C32 structure. We argue that stabilization of the δ -UZr 2 phase relative to the α -Zr (hcp) structure is due to an increase of the Zr d -band occupancy that occurs when U is alloyed with Zr. A comparison with stabilization of the ω -phase (also C32) in Zr under compression is made.
A multicomponent approach to substituted benzenes involving sequential nickel-catalyzed reactions

Two sequential nickel-catalyzed reactions allow the preparation of highly functionalized alkylidene cyclohexenols. Dehydration of the resulting cycloadducts allows the preparation of densely functionalized aromatic ring systems, whereas a simple sequence involving oxidation followed by carbonyl addition or enolization allows additional diversity incorporation.
Comments on Supersymmetry Algebra and Contact Term in Matrix String Theory

We write down two supercharges in the matrix string theory at the leading order, following previous works relating the matrix string theory to the light-cone superstring field theory. We check the supersymmetry algebra at this order and also discuss the problems of higher order contact terms.
Propagation of quantized fields through negative-index media

Dielectric materials in which both the relative permittivity, e, and the relative permeability, μ, are negative exhibit striking optical properties, which are a consequence of the fact that the effective index of refraction in such materials is negative. Most studies of the propagation of electromagnetic fields in these media have concentrated on classical fields with well-defined phases. In contrast, I use simple fully-quantized models to illustrate how some of the striking properties of negative-index media are manifested in the propagation of single, spontaneously emitted, photons. Single-photon quantum fields do not have an absolute phase, but the examples in this paper demonstrate a quantum analog of the negative phase accumulated by classical fields as photons propagate through negative-index media. The single photons also exhibit classical reflection and transmission coefficients, as well as the expected group velocity.
An immunologic study of spouses and siblings of asymptomatic hemophiliacs.

A transmissable agent may be responsible for the recent occurrence of the acquired immune deficiency syndrome (AIDS) in female heterosexual partners and infant contacts of AIDS victims or of persons at increased risk for AIDS. We, therefore, evaluated the clinical and immunologic status of 18 hemophiliac-spouse pairs and 19 hemophiliac-sibling pairs. Using surface marker assays of lymphocyte subpopulations, we found a mean T helper cell/T suppressor cell (H/S) ratio ± S.E.M. in 18 hemophiliac adults of 1.11 ± 0.15 (eleven <1.00), in their 18 spouses of 1.88 ± 0.13 (none <1.00), in 19 hemophiliac children of 1.54 ± 0.11 (three(<1.00), and in their 19 siblings of 1.87 ±0.11 (none< 1.00). Both hemophiliac adult and hemophiliac children mean H/S ratios differed significantly (p < 0.05) from the control mean ratio of 2.22 ± 0.16 and from the mean of their respective non-hemophiliac spouse or sibling group (p < 0.05). The mean ratio of hemophiliac adults differed significantly from that of hemophiliac children (p < 0.05). These findings suggest that lymphocyte alterations in hemophiliacs are secondary to their therapy, are not influenced by genetic factors, and are not related to an infectious agent that is easily transmissable by close contact.
Temperature measurements by light-scattering methods

Abstract In the last fifteen years, a variety of laser-based, light-scattering techniques have been developed for the measurement of local temperature in gaseous flows. The principal application has been to laminar and turbulent flames, though some of the methods have been extended to nonreactive flows at temperatures of 100–1000 K. The techniques considered in this review include spontaneous vibrational and rotational Raman scattering, Rayleigh scattering, and laser-induced fluorescence, both two-line and monochromatic. Consideration is also given to more recent work which extends the Rayleigh and fluorescence methods to planar thermometry.
Parametric, semiparametric, and nonparametric estimation of characteristic values within mass assessment and hedonic pricing models

Parametric estimators, such as OLS, attain high efficiency for well-specified models. Nonparametric estimators greatly reduce specification error but at the cost of efficiency. Semiparametric estimators compromise between these dual goals of efficiency and specification error. Semiparametric estimators can assume general forms within classes of functional forms. This paper applies OLS, the kernel nonparametric regression estimator, and the semi-parametric estimator of Powell, Stock, and Stoker (1989) to a data set, which should, based on theory and previous empirical work, yield positive coefficients. The semiparametric estimator, on average, displayed the performance most consistent with prior expectations followed by the nonparametric and parametric estimators. In addition, the paper shows how the semiparametric estimator can provide insights into the form of misspecification and suggest data transformations.
Dehydrative C–H Alkylation and Alkenylation of Phenols with Alcohols: Expedient Synthesis for Substituted Phenols and Benzofurans

A well-defined cationic Ru–H complex catalyzes the dehydrative C–H alkylation reaction of phenols with alcohols to form ortho-substituted phenol products. Benzofuran derivatives are efficiently synthesized from the dehydrative C–H alkenylation and annulation reaction of phenols with 1,2-diols. The catalytic C–H coupling method employs cheaply available phenols and alcohols, exhibits a broad substrate scope, tolerates carbonyl and amine functional groups, and liberates water as the only byproduct.
Protoplanetary Disks and Their Evolution

Flattened, rotating disks of cool dust and gas extending for tens to hundreds of astronomical units are found around almost all low-mass stars shortly after their birth. These disks generally persist for several million years, during which time some material accretes onto the star, some is lost through outflows and photoevaporation, and some condenses into centimeter- and larger-sized bodies or planetesimals. Through observations mainly at IR through millimeter wavelengths, we can determine how common disks are at different ages; measure basic properties including mass, size, structure, and composition; and follow their varied evolutionary pathways. In this way, we see the first steps toward exoplanet formation and learn about the origins of the Solar System. This review addresses observations of the outer parts, beyond 1 AU, of protoplanetary disks with a focus on recent IR and (sub)millimeter results and an eye to the promise of new facilities in the immediate future.
U Cephei revisited

Observations of U Cephei made by C. M. Buffer, et al, in 1950–51 and in 1959, are presented here to contrast with other observations made by Huffer and others.
Efficient codebook search for vector quantization: exploiting inherent codebook structure

A major problem associated with vector quantization is the complexity of exhaustive codebook search. This problem has hindered the use of this powerful technique for lossy image compression. An exhaustive codebook search requires that an input vector be compared against each code vector in the codebook in order to find the code vector that yields the minimum distortion. Because an exhaustive search does not capitalize on any underlying structure of the code vectors in hyperspace, other researchers have proposed technique that exploit codebook structure, but these technique typically result in sub-optimal distortion. We propose a new method that exploits the nearest neighbor structure of code vectors and significantly reduces the number of computations required in the search process. However, this technique does not introduce additional distortion, and is thus optimal. Our method requires a one time precomputation and a small increase in the memory required to store the codebook. In the best case, arising when the code vectors are largely dispersed in the hyperspace, our method requires only partial search of the codewords. In the worst case, our method requires a full search of the codebook. Since the method depends on the structure of the code vectors in the hyperspace, it is difficult to determine its efficiency in all cases, but test on typical image compression tasks have shown that this method offers on average an 81.16 percent reduction in the total number of multiples, additions and subtractions required as compared to full search.
Performance of nonlinear photonic crystal devices at high bit rates

I investigate theoretically the performance limits for all-optical switching devices incorporating photonic crystals made of nonlinear materials operating at high bit rates. I compare two switching techniques--shifting of the photonic bandgap and the more traditional interferometric method enhanced by slow wave propagation in photonic crystals-and show that the latter always has an advantage. I also demonstrate that the benefits provided by the photonic crystal in the interferometer are still severely limited by the dispersion and become significant only in materials combining high nonlinearity, high index contrast, and high damage threshold.
Structure of a Triglyceride Microemulsion: A Small-Angle Neutron Scattering Study

The microscopic structure of a microemulsion of triolein oil, aqua (water−ethanol, 80/20 wt %), and polyoxyethylene (40) sorbitol hexaoleats has been studied with small-angle neutron scattering. Co...
Optical properties of crystals with spatial dispersion—Josephson plasma resonance in layered superconductors

We derive the transmission coefficient, T(ω), for grazing incidence of crystals with spatial dispersion accounting for the excitation of multiple modes with different wave vectors k for a given frequency ω. The generalization of the Fresnel formulas contains the refraction indices of these modes as determined by the dielectric function (ω,k). Near frequencies ωe, where the group velocity vanishes, T(ω) depends also on an additional parameter determined by the crystal microstructure. The transmission T is significantly suppressed, if one of the excited modes is decaying into the crystal. We derive these features microscopically for the Josephson plasma resonance in layered superconductors.
Magnesium-Catalyzed Asymmetric Direct Aldol Addition of Ethyl Diazoacetate to Aromatic, Aliphatic, and α,β-Unsaturated Aldehydes

Magnesium-catalyzed enantioselective aldol between ethyl diazoacetate and aromatic, aliphatic, and alpha,beta-unsaturated aldehydes affords alpha-diazo-beta-hydroxy-esters in high enantioselectivities. Aldol adducts resulting from this asymmetric transformation are versatile intermediates toward the synthesis of several ester containing chiral building blocks.
A convenient and versatile synthesis of 6,5- and 7,5-fused bicyclic lactams as peptidomimetics

Chemo-selective reduction of the pyroglutamate ring carbonyl in a serine-pyroglutamate or homoserine to pyroglutamate dipeptide gave a hemiaminal. Treatment of the hemiaminal with a catalytic amount of TFA in CH2Cl2 generated an N-acyliminium ion that was intramolecularly trapped by the side-chain hydroxyl to give a 6,5 or 7,5-bicyclic lactam.
Foreign living experience as a predictor of domestic travel behavior

Travel behavior researchers have long been interested in various factors influencing how individuals make transportation decisions. Research has shown that foreign born residents and recent immigrants to the US exhibit significantly different travel behavior than native born populations in the same regions. This paper expands on that existing research by examining the travel behavior data of 662 students from Brigham Young University (52.1% of whom have lived outside the United States for more than 60 consecutive days). First the paper identifies if an individual's experience living abroad results in a change in travel behavior upon their return to the United States; second, if the foreign location where the experience was gained influences any behavioral change, and if so which regions of the world produce the greatest influence?; and third, if the duration of an individual's residence abroad affects their travel behavior and transportation perceptions upon returning to the United States. The analysis revealed that individuals who have lived abroad do exhibit a significant change in travel behavior upon returning to the United States, and the continent where the individual lived does significantly affect their change in travel behavior. However it appears that this change in behavior upon their return to the United States may be a regression to the mean, manifested by individuals adopting travel behavior similar to the transportation culture of their domestic environment. The location and duration of foreign experience does not have a significant impact on the current travel behavior of the individuals represented in this sample.
Bose–Einstein condensation of excitons in bilayer electron systems

An exciton is the particle-like entity that forms when an electron is bound to a positively charged 'hole'. An ordered electronic state in which excitons condense into a single quantum state was proposed as a theoretical possibility many years ago. We review recent studies of semiconductor bilayer systems that provide clear evidence for this phenomenon and explain why exciton condensation in the quantum Hall regime, where these experiments were performed, is as likely to occur in electron–electron bilayers as in electron–hole bilayers. In current quantum Hall excitonic condensates, disorder induces mobile vortices that flow in response to a supercurrent and limit the extremely large bilayer counterflow conductivity.