cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhancing Binary Images of Non-Binary LDPC Codes

We investigate the reasons behind the superior performance of belief propagation decoding of non- binary LDPC codes over their binary images when the transmission occurs over the binary erasure channel. We show that although decoding over the binary image has lower complexity, it has worse performance owing to its larger number of stopping sets relative to the original non-binary code. We propose a method to find redundant parity-checks of the binary image that eliminate these additional stopping sets, so that we achieve performance comparable to that of the original non-binary LDPC code with lower decoding complexity.
Autophagy dysregulation in cell culture and animals models of Spinal Muscular Atrophy

Abnormal autophagy has become a central thread linking neurodegenerative diseases, particularly of the motor neuron. One such disease is spinal muscular atrophy (SMA), a genetic neuromuscular disorder caused by mutations in the SMN1 gene resulting in low levels of Survival Motor Neuron (SMN) protein. Despite knowing the causal protein, the exact intracellular processes that are involved in the selective loss of motor neurons remain unclear. Autophagy induction can be helpful or harmful depending on the situation, and we sought to understand the state of the autophagic response in SMA. We show that cell culture and animal models demonstrate induction of autophagy accompanied by attenuated autophagic flux, resulting in the accumulation of autophagosomes and their associated cargo. Expression of the SMN-binding protein a-COP, a known modulator of autophagic flux, can ameliorate this autophagic traffic jam.
General and Scalable Amide Bond Formation with Epimerization-Prone Substrates Using T3P and Pyridine

The mild combination of T3P (n-propanephosphonic acid anhydride) and pyridine has been developed for low-epimerization amide bond formation and implemented for the synthesis of a key intermediate to a glucokinase activator. This robust method is general for the coupling of various racemization-prone acid substrates and amines, including relatively non-nucleophilic anilines, and provides amides in high yields with very low epimerization. With easy reaction setup and product isolation, this protocol offers several practical and experimental benefits.
Global P, PP, and PKP wave microseisms observed from distant storms

Microseisms are the continuous background vibrations of the Earth observed between earthquakes. Most microseism studies have focused on low frequency energy (0.05–0.5 Hz) propagating as surface waves, but in the microseism spectrum there is also energy that propagates as body waves (P-waves). Using array analysis on southern California stations we show that these body waves are generated in the ocean from distant storms and propagate deep within the Earth's mantle and core as P, PP and PKP phases. Comparisons with ocean wave hindcast data identify several distinct source regions in both the northern and southern hemispheres. Analyses of these body waves demonstrate that microseisms often have a strong P-wave component originating from distant locations.
Silica-alumina-supported acidic molybdenum catalysts - TPR and XRD characterization

A series of silica-aluminas with controlled composition has been synthesized and used as supports for Mo oxide catalysts. X-ray diffraction (XRD) and temperature-programmed reduction (TPR) were used to study the role of support composition upon the stability of various oxidic species, including products of solid state reaction between Mo oxide and silica-alumina. In general, the reducibility of Mo increases with increasing Mo loading, regardless of support composition. For a fixed Mo loading, however, extent of reduction increases with SiO2 content and shows a maximum at a composition SiO2 : Al2O3 = 75 : 25 (wt%). Except for silica-rich catalysts, the average oxidation state of Mo does not reach below +4 at the conditions used for TPR (maximum temperature: 550°C). Most of the support compositions yield XRD-amorphous Mo oxide. Only Mo-rich and silica-rich catalysts (MoO3 ≥ 12 wt%; SiO2 ≥ 50 wt%) contain crystalline phases of Mo: orthorhombic MoO3 on 100% SiO2, and MoO3 and Al2(MoO4)3 On silica-aluminas.
A Magnetically Supported Photodissociation Region in M17

The southwestern (SW) part of the Galactic H II region M17 contains an obscured ionization front that is most easily seen at infrared and radio wavelengths. It is nearly edge-on, thus offering an excellent opportunity to study the way in which the gas changes from fully ionized to molecular as radiation from the ionizing stars penetrates into the gas. M17 is also one of the very few H II regions for which the magnetic field strength can be measured in the photodissociation region ( PDR) that forms the interface between the ionized and molecular gas. Here we model an observed line of sight through the gas cloud, including the H+, H0 (PDR), and molecular layers, in a fully self-consistent single calculation. An interesting aspect of the M17 SW bar is that the PDR is very extended. We show that the strong magnetic field that is observed to be present inevitably leads to a very deep PDR, because the structure of the neutral and molecular gas is dominated by magnetic pressure, rather than by gas pressure, as previously had been supposed. We also show that a wide variety of observed facts can be explained if a hydrostatic geometry prevails, in which the gas pressure from an inner X-ray hot bubble and the outward momentum of the stellar radiation field compress the gas and its associated magnetic field in the PDR, as has already been shown to occur in the Orion Nebula. The magnetic field compression may also amplify the local cosmic-ray density. The pressure in the observed magnetic field balances the outward forces, suggesting that the observed geometry is a natural consequence of the formation of a star cluster within a molecular cloud.
DETERMINING THE AMPLITUDE OF MASS FLUCTUATIONS IN THE UNIVERSE

We present a method for determining the amplitude of mass fluctuations on 8 h-1 Mpc scale, σ8. The method utilizes the rate of evolution of the abundance of rich clusters of galaxies. Using the Press-Schechter approximation, we show that the cluster abundance evolution is a strong function of σ8: dlogn/dz∝-1/σ28; low-σ8 models evolve exponentially faster than high-σ8 models, for a given mass cluster. For example, the number density of Coma-like clusters decreases by a factor of ~103 from z=0 to z0.5 for σ8=0.5 models, while the decrease is only a factor of ~5 for σ81. The strong exponential dependence on σ8 arises because clusters represent rarer density peaks in low-σ8 models. We show that the evolution rate at z1 is insensitive to the density parameter Ω or to the exact shape of the power spectrum. Cluster evolution therefore provides a powerful constraint on σ8. Using available cluster data to z~0.8, we find σ8=0.83±0.15. This amplitude implies a bias parameter bσ−18=1.2±0.2, i.e., a nearly unbiased universe with mass approximately tracing light on large scales. When combined with the present-day cluster abundance normalization, σ8Ω0.50.5, the cosmological density parameter can be determined: Ω0.3±0.1.
Non-cyclotomic presentations of modules and prime-order automorphisms of Kirchberg algebras

We prove the following theorem: let $A$ be a UCT Kirchberg algebra, and let $\alpha$ be a prime-order automorphism of $K_*(A)$, with $\alpha([1_A])=[1_A]$ in case $A$ is unital. Then $\alpha$ is induced from an automorphism of $A$ having the same order as $\alpha$. This result is extended to certain instances of an equivariant inclusion of Kirchberg algebras. As a crucial ingredient we prove the following result in representation theory: every module over the integral group ring of a cyclic group of prime order has a natural presentation by generalized lattices with no cyclotomic summands.
Gamma-ray astronomy by the air shower technique: Performance and perspectives

The techniques for γ-ray astronomy at energies ≥10 TeV using air shower detectors are discussed. The results, based on a number of large arrays, are negative, with no point sources being identified. While the contributions to γ-ray astronomy so far have been only upper limits, these arrays in the future will make significant progress in the understanding of cosmic rays in the energy range 1013 eV to 1016 eV. Also, contributions to solar physics are being made by observations of shape and time dependence of the shadow of the Sun as observed in cosmic rays. For the advancement of γ-ray astronomy a greater sensitivity is required in the energy region of 10 TeV. A number of promising techniques to accomplish a greater sensitivity are discussed. They include the enlargement of the Tibet array at 4300 meters altitude, the array of open photomultipliers at La Palma (AIROBICC), which views the shower by the Cherenkov photons produced in the atmosphere, and the instrumentation of a pond at Los Alamos with photomultipliers (Milagro).
Observation of the cesium clock transition using laser-cooled atoms in a vapor cell

Cesium atoms in a vapor cell have been trapped and cooled by using light from laser diodes. The 6S F = 4, m = 0 → 6S F = 3, m = 0 hyperfine clock transition was excited as these atoms then fell 2.5 cm in darkness. We observed a linewidth of 8 Hz with good signal-to-noise ratio. This gave a short-term fractional frequency resolution of 6.5×10-12sec, and there is potential for substantial improvement. The apparatus is extremely simple and compact, consisting of a small cesium vapor cell and two diode lasers.
Polar Field Puzzle: Solutions from Flux-transport Dynamo and Surface-transport Models

Polar fields in solar cycle 23 were about 50% weaker than those in cycle 22. The only theoretical models which have addressed this puzzle are surface-transport models and flux-transport dynamo models. Comparing polar fields obtained from numerical simulations using surface-flux-transport models and flux-transport dynamo models, we show that both classes of models can explain the polar field features within the scope of the physics included in the respective models. In both models, how polar fields change as a result of changes in meridional circulation depends on the details of meridional circulation profile used. Using physical reasoning and schematics as well as numerical solutions from a flux-transport dynamo model, we demonstrate that polar fields are determined mostly by the strength of a surface poloidal source provided by the decay of tilted, bipolar active regions. The profile of a meridional flow with the latitude and its changes with time have much less effect in flux-transport dynamo models than in surface-transport models.
Applications of the Optical Differential Thermal Analysis.

Abstract ODTA detects temperature contact-less, hence, It expands the upper usable temperature limit of DTA up to 3600°C accordingly suitable for studies of systems where enthalpic changes occur at high temperatures. Application of the computer graphics for the evaluation of the ODTA curves is demonstrated on melting of Y 2 O 3 .Al 2 O 3 and YAlO 3 -GdAlO 3 systems. Measurement errors occurring at temperatures above 1900°C are pointed out and possibilities for their elimination or at least diminution are discussed.
A new approach to numerical quantum field theory

Abstract In this note we present a new numerical method for solving Lattice Quantum Field Theory. This Source Galerkin Method is fundamentally different in concept and application from Monte Carlo based methods which have been the primary mode of numerical solution in Quantum Field Theory. Source Galerkin is not probabilistic and treats fermions and bosons in an equivalent manner.
LEARNING STEPPINGSTONES FOR PROBLEM SOLVING

One goal of Artificial Intelligence is to develop and understand computational mechanisms for solving difficult real-world problems. Unfortunately, domains traditionally used in general problem-solving research lack important characteristics of real-world domains, making it difficult to apply the techniques developed. Most classic AI domains require satisfying a set of Boolean constraints. Real-world problems require finding a solution that meets a set of Boolean constraints and performs well on a set of real-valued constraints. In addition, most classic domains are static while domains from the real world change. In this paper we demonstrate that SteppingStone, a general learning problem solver, is capable of solving problems with these characteristics. SteppingStone heuristically decomposes a problem into simpler subproblems, and then learns to deal with the interactions that arise between the subproblems. In lieu of an agreed upon metric for problem difficulty, we choose significant problems that are difficult for both people and programs as good candidates for evaluating progress. Consequently we adopt the domain of logic synthesis from VLSI design to demonstrate SteppingStone’s capabilities.
Optimal Bandwidth for High Efficiency Thermoelectrics

The thermoelectric figure of merit (ZT) in narrow conduction bands of different material dimensionalities is investigated for different carrier scattering models. When the bandwidth is zero, the transport distribution function (TDF) is finite, not infinite as previously speculated by Mahan and Sofo [Proc. Natl. Acad. Sci. U.S.A. 93, 7436 (1996)], even though the carrier density of states goes to infinity. Such a finite TDF results in a zero electrical conductivity and thus a zero ZT. We point out that the optimal ZT cannot be found in an extremely narrow conduction band. The existence of an optimal bandwidth for a maximal ZT depends strongly on the scattering models and the dimensionality of the material. A nonzero optimal bandwidth for maximizing ZT also depends on the lattice thermal conductivity. A larger maximum ZT can be obtained for materials with a smaller lattice thermal conductivity.
The use of dedicated methodology and statistical reviewers for peer review: a content analysis of comments to authors made by methodology and regular reviewers.

Abstract Study objective: In 1997, Annals of Emergency Medicine initiated a protocol by which every original research article, in addition to each regular review, was concurrently evaluated by 1 of 2 methodology and statistical reviewers. We characterized and contrasted comments made by the methodology and regular peer reviewers. Methods: After pilot testing, interrater reliability assessment, and revision, we finalized a 99-item taxonomy of reviewer comments organized in 8 categories. Two authors, uninvolved in the writing of reviews, classified each comment from a random sample of methodology reviews from 1999. For 30 of these reviews (15 for each methodology reviewer), the 2 authors also scored all (range 2 to 5) regular reviews. Results: Sixty-five reviews by methodologist A, 60 by methodologist B, and 68 by regular reviewers were analyzed. Comments by methodologist A most frequently concerned the presentation of results (33% of all comments) and methods (17%). Methodologist B commented most frequently on presentation of results (28%) and statistical methods (16%). Regular reviewers most frequently made non-methodology/statistical comments (45%) and comments on presentation of results (18%). Of note, comments made by methodology and regular reviewers about methods issues were often contradictory. Conclusion: The distributions of comments made by the 2 methodology and statistical reviewers were similar, although reviewer A emphasized presentation and reviewer B stressed statistical issues. The regular reviewers (most of whom were unaware that a dedicated methodology and statistical reviewer would be reviewing the article) paid much less attention to methodology issues. The 2 dedicated methodology and statistical reviewers created reviews that were similarly focused and emphasized methodology issues that were distinct from the issues raised by regular reviewers. [ Ann Emerg Med. 2002;40:329-333.]
The finite cardinalities of level sets of the Takagi function

Abstract Let T be Takagiʼs continuous but nowhere-differentiable function. It is known that almost all level sets (with respect to Lebesgue measure on the range of T) are finite. We show that the most common cardinality of the level sets of T is two, and investigate in detail the set of ordinates y such that the level set at level y has precisely two elements. As a by-product, we obtain a simple iterative procedure for solving the equation T ( x ) = y . We show further that any positive even integer occurs as the cardinality of some level set, and conjecture that all even cardinalities occur with positive probability if an ordinate y is chosen at random from the range of T. The key to the results is a system of set equations for the level sets, which are derived from the partial self-similarity of T. These set equations yield a system of linear relationships between the cardinalities of level sets at various levels, from which all the results of this paper flow.
Effects of Secular Interactions in Extrasolar Planetary Systems

This paper studies the effects of dynamical interactions among the planets in observed extrasolar planetary systems, including hypothetical additional bodies, with a focus on secular perturbations. These interactions cause the eccentricities of the planets to explore a distribution of values over timescales that are long compared to observational time baselines but short compared to the age of the systems. The same formalism determines the eccentricity forcing of hypothetical test bodies (terrestrial planets) in these systems, and we find which systems allow for potentially habitable planets. Such planets would be driven to nonzero orbital eccentricity and we derive the distribution of stellar flux experienced by the planets over the course of their orbits. The general relativistic corrections to secular interaction theory are included in the analysis, and such effects are important in systems with close planets (~4 day orbits). Some extrasolar planetary systems (e.g., Andromedae) can be used as a test of general relativity, whereas in other systems, general relativity can be used to constrain the system parameters (e.g., sin i 0.93 for HD 160691). For the case of hot Jupiters we discuss how the absence of observed eccentricity implies the absence of companion planets.
Consistent Approximations for the Optimal Control of Constrained Switched Systems---Part 2: An Implementable Algorithm

In the first part of this two-paper series, we presented a conceptual algorithm for the optimal control of constrained switched systems and proved that this algorithm generates a sequence of points...
CONCEPTUAL DESIGN OF REDUCED ENERGY TRANSPORTS

The paper reports the results of a conceptual design study of new near-term fuel-conservative aircraft. A parametric study was made to determine the effects of cruise Mach number and fuel cost on the optimum configuration characteristics and relative economic performance. Supercritical wing technology and advanced engine cycles were assumed. For each design, the wing geometry was selected to maximize an economic figure of merit which reflects the potential rate of return on investment. Based on the results of the parametric study, a reduced energy configuration was selected. Compared with existing transport design, the reduced energy design has a higher aspect ratio wing with lower sweep, and cruises at a slightly lower Mach number. It yields about 30% more seat-miles/gal than current wide-body aircraft. At the higher fuel costs anticipated in the future, the reduced energy design has about the same economic performance as existing designs with the same technology level. As an example of a far-term technology application, a design with a composite material wing was also investigated.
Synthesis of proteoglycan 4 by chondrocyte subpopulations in cartilage explants, monolayer cultures, and resurfaced cartilage cultures.

Objective To quantify the levels of proteoglycan 4 (PRG4) expression by subpopulations of chondrocytes from superficial, middle, and deep layers of normal bovine calf cartilage in various culture systems. Methods Bovine calf articular cartilage discs or isolated cells were used in 1 of 3 systems of chondrocyte culture: explant, monolayer, or transplant, for 1–9 days. PRG4 expression was quantified by enzyme-linked immunosorbent assay of spent medium and localized by immunohistochemistry at the articular surface and within chondrocytes in explants and cultured cells. Results Superficial chondrocytes secreted much more PRG4 than did middle and deep chondrocytes in all cultures. The pattern of PRG4 secretion into superficial culture medium varied with the duration of culture, decreasing with time in explant culture (from ∼25 μg/cm2/day on days 0–1 to ∼3 μg/cm2/day on days 5–9), while increasing in monolayer culture (from ∼1 pg/cell/day on days 0–1 to ∼7 pg/cell/day on days 7–9) and tending to increase in transplant culture (reaching ∼2 μg/cm2/day by days 7–9). In all of the culture systems, inclusion of ascorbic acid stimulated PRG4 secretion, and the source of PRG4 was immunolocalized to superficial cells. Conclusion The results described here indicate that the phenotype of PRG4 secretion by chondrocytes in culture is generally maintained, in that PRG4 is expressed to a much greater degree by chondrocytes from the superficial zone than by those from the middle and deep zones. The marked up-regulation of PRG4 synthesis by ascorbic acid may have implications for cartilage homeostasis and prevention of osteoarthritic disease. Transplanting specialized cells that secrete PRG4 to a surface may impart functional lubrication and be generally applicable to many tissues in the body.
Reverse Mortgages and Prepayment Risk

This paper presents a detailed assessment of the Connecticut Housing Finance Authority (CHFA) reverse annuity mortgage (RAM) program. Because of the size and payment history of the program, the analysis provides an empirical framework on which to develop and assess other home equity conversion (HEC) programs. The program offers insights into the economic impact of these programs and the factors affecting prepayment. The program issued 765 annuities over five years, and 240 of these loans have terminated payments. The annuity payments had a demonstrable financial impact on the elderly participants, with an 88% average annual income increase. Prepayment rates varied across borrower and loan characteristics. The rates were most sensitive to marital status and were heavily affected by the age of the borrower and the term of the loan. Although default risk exists, the evidence indicates a low probability of the loan value exceeding the house value.
Photosynthesis studies with tritiated water

Abstract A study has been made of the incorporation patterns of tritium from tritium oxide by Chlorella cells under conditions of light and dark. A new apparatus has been designed for use in photosynthesis experiments which necessitate the employment of dense cell suspensions and substrates of high specific activity (I C/ml). The incorporation patterns of 14CO2 in the presence and absence of tritiated water showed little evidence of physiological damage due to radiation. The substances incorporating tritium were essentially the same as those incorporating 14C from 14CO2. However, the percentage distribution of the tracer among the labelled compounds showed considerable differences from the carbon pattern. At the shortest incubation periods in the light, tritium appeared mainly in the sugar monophosphates, phosphoglyceric acid, aspartic acid, glutamic acid, and malic acid. These substances also incorporated label most rapidly in the dark, though in this case a greater percentage of the activity fixed appeared in the amino acids. About three times as much tracer was fixed in the light as in the dark. The total activity fixed, and its distribution, was affected to some extent by the presence of ammonium or nitrate ions in the medium. Glycollic acid was labelled very early, and was the most active compound present. A scheme for hydrogen transport in photosynthesis involving an alternate oxidation and reduction of glycollic and glyxylic acids is proposed. The difficulties of interpreting the results of biochemical studies with hydrogen isotopes due to non-specific exchange reactions are discussed.
Hamiltonians for the Quantum Hall Effect on Spaces with Non-Constant Metrics

The problem of studying the quantum Hall effect on manifolds with non constant metric is addressed. The Hamiltonian on a space with hyperbolic metric is determined, and the spectrum and eigenfunctions are calculated in closed form. The hyperbolic disk is also considered and some other applications of this approach are discussed as well.
Catalytic Enantioselective Hydroboration of Cyclopropenes

2,2-Disubstituted cyclopropyl boronates have been synthesized with high degrees of diastereo- and enantioselectivity via the rhodium-catalyzed asymmetric hydroboration of 3,3-disubstituted cyclopropenes. A strong directing effect of ester and alkoxymethyl substituents has been demonstrated. The directing effect was found to be necessary in achieving high degrees of enantiomeric induction. Selected cyclopropylboronic derivatives were successfully employed in the Suzuki cross-coupling reaction to produce the corresponding optically active aryl- and vinylcyclopropanes in good yields.
Template-directed one-step synthesis of cyclic trimers by ADMET

A trifurcated template, containing three secondary dialkylammonium ion recognition sites for encirclement by a dibenzo [24]crown-8-containing acyclic diene, is used to promote acyclic diene metatheses (ADMET) catalyzed by ruthenium−alkylidene complexes, affording a cyclic trimer in 55% yield. Following this one-step, threefold ADMET reaction, the resulting cyclic trimer was isolated by preparative HPLC and characterized by NMR spectroscopy and mass spectrometry.
Dispersion of solid particles in compressible mixing layers

Flow visualization and subsequent digital image processing were used to investigate the dispersion of solid particles in compressible free shear layers with convective Mach numbers of 0.51 and 0.86. A sheet of light formed using a Nd:YAG pulsed laser was used to illuminate the dispersed particles of nominal diameters 5, 17, and 62 yum. An intensified CCD camera captured images of the flowfield and subsequent digital image processing was used to locate particles in the images. Visual and statistical results for the Mc = 0.51 case showed dispersion trends similar to those in incompressible cases where particle dispersion depends largely on the ratio of particle time scale to fluid time scale (Stokes number). In particular, high levels of dispersion occurred for a range of Stokes numbers. However, results showed that three-dimensionality and disorganization of large scale structures in the higher compressibility case (Mc = 0.86) drastically reduced their entrainment and dispersion capabilities. Selective dispersion of particles was not observed for the range of Stokes numbers studied in the Mc = 0.86 case.
Swift Observations of Gamma-Ray Bursts

The Swift mission, launched on 20 November 2004, is detecting ~ 100 gamma-ray bursts (GRBs) each year, and immediately (within ~ 90 s) starting X-ray and UV/optical observations of the afterglow. It has already collected an impressive database including prompt emission to higher sensitivities than BATSE, uniform monitoring of afterglows, and rapid follow-up by other observatories notified through the Gamma-ray bursts Coordinates Network (GCN). The X-ray afterglows have been found to have complex temporal shapes including tails emission from the prompt phase and bright flares. X-ray and optical afterglow detections from short bursts have led to accurate localizations. It is found that they can occur in non-star forming galaxies or regions, whereas long GRBs are strongly concentrated within star forming regions. This is consistent with the NS merger model. Swift has greatly increased the redshift range of GRB detection. The highest redshift GRBs, at z ~ 5-6, are approaching the era of reionization. Ground-based deep optical spectroscopy of high redshift bursts is giving metallicity measurements and other information on the source environment to much greater distance than other techniques. The localization of GRB 060218 in a nearby galaxy, and association with SN 2006aj, added a valuable member to the class of GRBs with detected supernova. The prospects for future progress are excellent given the > 10 year orbital lifetime of the Swift satellite.
The Impact of the SBIR on Creating Entrepreneurial Behavior

The U.S. Congress created the Small Business Innovation Research program in 1982 in response to the loss of American competitiveness in global markets. Congress mandated that each federal agency allocate approximately 4% of its annual budget to fund innovative small firms to help restore American international competitiveness. This article examines the impact of the SBIR. Specifically, the authors identify the degree to which (a) SBIR recipients have altered their career choices as a result of the award, particularly with respect to commercialization in the form of a new firm, and (b) their behavior has “spilled over” by inducing other colleagues to commercialize their knowledge by starting a new firm. This enables one to determine how the SBIR has contributed to changing the behavior of knowledge workers and to the creation of a science-based entrepreneurial economy.
A Hardy field extension of Szemerédi's theorem

Abstract In 1975 Szemeredi proved that a set of integers of positive upper density contains arbitrarily long arithmetic progressions. Bergelson and Leibman showed in 1996 that the common difference of the arithmetic progression can be a square, a cube, or more generally of the form p ( n ) where p ( n ) is any integer polynomial with zero constant term. We produce a variety of new results of this type related to sequences that are not polynomial. We show that the common difference of the progression in Szemeredi's theorem can be of the form [ n δ ] where δ is any positive real number and [ x ] denotes the integer part of x. More generally, the common difference can be of the form [ a ( n ) ] where a ( x ) is any function that is a member of a Hardy field and satisfies a ( x ) / x k → ∞ and a ( x ) / x k + 1 → 0 for some non-negative integer k. The proof combines a new structural result for Hardy sequences, techniques from ergodic theory, and some recent equidistribution results of sequences on nilmanifolds.
Steady-state bumpless transfer under controller uncertainty using the state/output feedback topology

Linear quadratic (LQ) bumpless transfer design introduced recently by Turner and Walker gives a very convenient and straightforward computational procedure for the steady-state bumpless transfer operator synthesis. It is, however, found to be incapable of providing convergence of the output of the offline controller to that of the online controller in several industrial applications, producing bumps in the plant output in the wake of controller transfer. An examination of this phenomenon reveals that the applications in question are characterized by a significant mismatch, further referred to as controller uncertainty, between the dynamics of the implemented controllers and their models used in the transfer operator computation. To address this problem, while retaining the convenience of the Turner and Walker design, a novel state/output feedback bumpless transfer topology is introduced that employs the nominal state of the offline controller and, through the use of an additional controller/model mismatch compensator, also the offline controller output. A corresponding steady-state bumpless transfer design procedure along with the supporting theory is developed for a large class of systems. The new technique is shown to be capable of eliminating the online/offline controller output tracking errors under significant controller uncertainty, while preserving fast convergence of Turner and Walker design. Due to these features, it is demonstrated to solve a long-standing problem of high-quality steady-state bumpless transfer from the industry standard low-order nonlinear multiloop PID-based controllers to the modern multiinput-multioutput (MIMO) robust controllers in the megawatt/throttle pressure control of a typical coal-fired boiler/turbine unit.
Subjective and objective sleep quality in irritable bowel syndrome.

Abstract OBJECTIVE: The aim of this study was to compare subjective and objective measures of sleep quality in patients with irritable bowel syndrome (IBS) and controls. METHODS: The Pittsburgh Sleep Quality Index (PSQI) was used to measure subjective sleep quality, and polysomnography was performed during one night to obtain objective measures of sleep quality, including sleep efficiency, sleep latency, number of arousals, and percentage of slow-wave sleep. Participants were 15 IBS patients and 15 healthy controls. RESULTS: The results showed a significantly increased global PSQI score in patients, as well as significantly higher scores on several subcomponents of the PSQI ( i.e., sleep quality, sleep latency, habitual sleep efficiency, and daytime dysfunction). Analysis of polysomnographic parameters revealed no significant group differences on any measure. CONCLUSIONS: Complaints of poor sleep quality in the absence of objective sleep abnormalities suggest altered sleep perception, and support that IBS involves exaggerated responses to normal internal or external stimuli.
A phenomenon in the theory of sorting

The proof that a proposed sorting method actually works frequently involves the observation that certain operations preserve the order introduced by previous operations. T h e present paper gives a unified treatment of this order-preservation phenomenon. A number of results about sorting networks and other sorting methods, previously proved in an ad hoc manner, are immediate consequences of our theorems. T h e following examples will serve to introduce the phenomenon.
Computing Triangulations of Mapping Tori of Surface Homeomorphisms

We present the mathematical background of a software package that computes triangulations of mapping tori of surface homeomorphisms, suitable for Jeff Weeks's program SnapPea. The package is an extension of the software described in [Brinkmann 2000]. It consists of two programs. jmt computes triangulations and prints them in a human-readable format. jsnap converts this format into SnapPea's triangulation file format and may be of independent interest because it allows for quick and easy generation of input for SnapPea. As an application, we obtain a new solution to the restricted conjugacy problem in the mapping class group.
Hiding a Heavy Higgs Boson at the 7 TeV LHC

A heavy Standard Model Higgs boson is not only disfavored by electroweak precision observables but is also excluded by direct searches at the 7 TeV LHC for a wide range of masses. Here, we examine scenarios where a heavy Higgs boson can be made consistent with both the indirect constraints and the direct null searches by adding only one new particle beyond the Standard Model. This new particle should be a weak multiplet in order to have additional contributions to the oblique parameters. If it is a color singlet, we find that a heavy Higgs with an intermediate mass of 200–300 GeV can decay into the new states, suppressing the branching ratios for the standard model modes, and thus hiding a heavy Higgs at the LHC. If the new particle is also charged under QCD, the Higgs production cross section from gluon fusion can be reduced significantly due to the new colored particle one-loop contribution. Current collider constraints on the new particles allow for viable parameter space to exist in order to hide a heavy Higgs boson. We categorize the general signatures of these new particles, identify favored regions of their parameter space and point out that discovering or excluding them at the LHC can provide important in- direct information for a heavy Higgs. Finally, for a very heavy Higgs boson, beyond the search limit at the 7 TeV LHC, we discuss three additional scenarios where models would be consistent with electroweak precision tests: including an additional vector-like fermion mixing with the top quark, adding another U(1) gauge boson and modifying triple-gauge boson couplings.
Chip scale topography evolution model for CMP process optimization

A new chip scale model integrating pad height distribution and it's interaction with topography on a patterned wafer was tested. Pad asperity height distribution was used to calculate mean contact pressure at a single asperity contact region. Material removal by a single asperity was evaluated from Hertzian elastic contact model and abrasive indentation model. Simulation on a test pattern predicted relatively higher removal rate and lower planarization efficiency with higher nominal down pressure. Oxide thickness variation over a test chip for a time period measured from specially designed test structure matched well with the model prediction.
Protein-targeted gadolinium-based magnetic resonance imaging (MRI) contrast agents: design and mechanism of action.

Magnetic resonance imaging (MRI) is a powerful medical diagnostic technique: it can penetrate deep into tissue, provide excellent soft tissue contrast with sub-millimeter resolution, and does not employ ionizing radiation. Targeted contrast agents provide an additional layer of molecular specificity to the wealth of anatomical and functional information already attainable by MRI. However, the major challenge for molecular MR imaging is sensitivity: micromolar concentrations of GdIII are required to cause a detectable signal change, which makes detecting proteins by MRI a challenge. Protein-targeted MRI contrast agents are bifunctional molecules comprising a protein-targeting moiety and typically one or more gadolinium chelates for detection by MRI. The ability of the contrast agent to enhance the MR image is termed relaxivity, and it depends upon many molecular factors, including protein binding itself. As in other imaging modalities, protein binding provides the pharmacokinetic effect of concentrating th...
When curiosity kills the profits: An experimental examination

Economic theory predicts that in a first-price auction with equal and observable valuations, bidders earn zero profits. Theory also predicts that if valuations are not common knowledge, then since it is weakly dominated to bid your valuation, bidders will bid less and earn positive profits. Hence, rational players in an auction game should prefer less public information. We are perhaps more used to seeing these results in the equivalent Bertrand setting. In our experimental auction, we find that individuals without information on each other's valuations earn more profits than those with common knowledge. Then, given a choice between the two sets of rules, half the individuals still preferred to have the public information. We discuss possible explanations, including ambiguity aversion.
The asset price incidence of capital gains taxes: evidence from the Taxpayer Relief Act of 1997 and publicly-traded real estate firms

Abstract We provide new evidence on the asset price incidence of corporate-level investment subsidies by examining the relative stock price performance of publicly traded companies in the real estate industry that should have been differentially affected by the capital gains tax rate reduction enacted in the Taxpayer Relief Act of 1997. By comparing real estate firms that have an organizational structure that allows entities who sell property to it to defer capital gains taxes and that plan to use the structure to acquire property with those that do not, we isolate the effect of the tax cut from industry trends and firm-level heterogeneity. When we examine the time period surrounding the reduction in the capital gains tax rate, our results suggest the tax change was substantially capitalized into lower share prices for these firms and the benefit of the seller’s capital gains tax deferral accrued mainly to the buyer of an appreciated property.
Numerical simulation and aerothermal physics of leading edge film cooling

AbstractA viscous flow solver based on the Runge-Kutta scheme has been modified for the numerical investigation of the aerothermal field due to the leading edge film cooling at a compound angle. An existing code has been modified to incorporate multiblock capabilities. Good agreement with the measured data has been achieved. The results of the numerical investigation have been used to analyse the vortex structure associated with the coolant jet-free-stream interaction to understand the contribution of different vortices on the cooling effectiveness and aerothermal losses. Two counter-rotating vortices generated by the interaction between the main flow and the coolant jet have been found to have a major influence in decreasing the cooling efficiency through strong entrainment of the hot fluid. Numerical simulation was carried out to investigate the influence of the inlet Mach number, the inlet turbulence intensity and the length scale on the aerothermal field due to the leading edge film cooling. Variation...
Silanol as a Removable Directing Group for the PdII‐Catalyzed Direct Olefination of Arenes

Need some direction? Silanol was developed as a directing group for the Pd(II)-catalyzed oxidative Heck-type reaction of arenes. A one-pot C-H activation/desilylation process of benzyldiisopropylsilanol was also demonstrated, providing a powerful approach for the synthesis of ortho-alkenyl-substituted alkylarenes. Considering the easily attachable and readily removable properties of the silanol group, this reaction will find broad synthetic applications.
Computer-simulated Fresnel diffraction using the Fourier transform

The study of Fresnel diffraction is an integral part of any course in physical optics. Fresnel diffraction occurs when an aperture is illuminated with coherent light and the resulting diffraction pattern appears on a screen, a finite distance from the aperture. In general, the techniques found in standard optics texts' to compute the intensity of the diffraction pattern as a function of position on the screen are limited and aperture-specific. However, as texts on modern optics show, we can formulate Fresnel diffraction in terms of the Fourier transform of a modified aperture function. The article presents a generalized method, using the Fourier transform, for computing and graphically displaying the Fresnel diffraction intensity pattern for any planar aperture. With the advent of the PC and packaged mathematical software containing the fast Fourier transform algorithm, it is now possible to perform these calculations with minimum effort. The advantage of this method is that you can obtain the entire pattern at once, in contrast to the standard methods' point-by-point evaluation process.
On semistability of nonlinear switched systems

This paper develops semistability analysis results for nonlinear switched systems. Semistability is the property whereby the solutions of a dynamical system converge to Lyapunov stable equilibrium points determined by the system initial conditions. The main results of the paper involve sufficient conditions for semistability using multiple Lyapunov functions and integral-type inequalities.
"Housing Prices and Fundamentals: The Role of a Supply Shifter."

This paper empirically investigates cointegrating relation between housing prices and economic fundamental variables in the US housing market. Employing simple yet rigorous econometric techniques, the present paper finds strong evidence in favor of cointegrating relations in most US states when both the demand and supply side fundamental variables are included in the cointegrating regression. This casts doubt on the previous empirical work that reported weak or no cointegrating relation of housing prices with mostly demand-side fundamental variables, which may have a misspecification problem. Further, cointegrating vector estimates seem consistent with economic theories only when both side fundamental variables are used.
A conversation with Sidney Winter on the contributions of Alfred Chandler

David J. Teece discusses with Sidney G. Winter some of the major contributions of Alfred D. Chandler, Jr. Topics discussed include path dependence and the organizational embeddedness of competences and capabilities, the recent financial crisis, and the electronic century in terms of Chandler's priorities. Teece and Winter also consider both the promise and limitations of the Chandlerian approach to related matters in business and management theory. Copyright 2010 The Author 2010. Published by Oxford University Press on behalf of Associazione ICC. All rights reserved., Oxford University Press.
Ambiphilic allenyl enolates: reactions with electrophiles

Abstract Allenyl enolates generated from 1,6 additions of organocopper reagents to 3-ethynyl-2-cycloalkenones act as ambident α,γ-nucleophiles. The γ:α ratio of products is a function of carbon hybridization, steric environment, and cycloalkenone ring size; typically, γ-products predominate.
Third-harmonic conversion of XeCl-laser radiation.

Observation of third-harmonic conversion of 308-nm radiation from an XeCl laser in argon is reported. Variation of the harmonic signal at 102.7 nm with pump power and argon pressure is characteristic of conversion of a tightly focused beam in a negatively dispersive medium with no saturation evident up to intensity levels of the order of 2 × 1011 W/cm2. Effects of the spatial and spectral characteristics of the XeCl-laser output on conversion efficiency are discussed.
High-speed trajectory control of a direct-drive manipulator

High-speed precision trimming of three-dimensional parts using laser-cutting industrial robots is addressed. A control system for direct-drive manipulators specially designed for high-speed trajectory control applications is developed. The concept of decoupled and invariant dynamics is discussed for a specific manipulator, and a simple procedure for system identification and control system design is presented. It is demonstrated that, through proper arm mechanism design, the control system can be greatly simplified and satisfactory control performance achieved. The arm mechanism design and control system are evaluated through simulations and experiments. Experimental tracking performance achieves a speed of 3 m/s and an acceleration of 3.8 g, with a joint mean tracking error of 0.0556 degrees . >
Structure of large incomplete sets in abelian groups

Let G be a finite abelian group and A be a subset of G. We say that A is complete if every element of G can be represented as a sum of different elements of A. In this paper, we study the following question What is the structure of a large incomplete set? We show that such a set is essentially contained in a maximal subgroup. As a co-product, we obtain a new proof for several earlier results, including a new proof for Diderrich’s conjecture in large groups.
Corrosion behavior of mesoporous transition metal nitrides

Abstract Transition metal nitrides (TMN) have many desirable characteristics such as high hardness and good thermal stability under reducing conditions. This work reports an initial survey of the chemical stability of mesoporous TM Ns ( TM =Nb, V, Cr and Ti) in water at 80 °C at neutral, acidic and alkaline pH. The mesoporous TMNs had specific surface areas of 25–60 m 2 /g with average pore sizes ranging from 10 to 50 nm. The high surface areas of these materials enhance the rate of corrosion per unit mass over that of a bulk material, making detection of corrosion much easier. The products were characterized by Rietveld refinement of powder X-ray diffraction (PXRD) patterns and by scanning electron microscopy (SEM). Several nitrides have corrosion rates that are, within error, not distinguishable from zero (±1 A/day). Of the nitrides examined, CrN appears to be the most corrosion resistant under acidic conditions. None of the nitrides studied are corrosion resistant under alkaline conditions.