cssi/SciSciGPT-SciSciNet huggingface dataset:
Supported Metal Cluster Catalysts

Abstract Highly dispersed metal catalysts containing supported clusters of only several metal atoms each, exemplified by Ir 4 and Ir 6 , were prepared by removal of CO ligands from supported precursors, for example, [Ir 4 (CO) 12 ] and [Ir 6 (CO) 16 ]. Transmission electron microscopy (TEM), extended X-ray absorption fine structure spectroscopy and density functional theory indicate the metal–support-oxygen coordination numbers and distances, which identify the supports as multidentate oxygen-donor ligands. Theory indicates that Ir 4 clusters in zeolite NaX are neutral or slightly negatively charged and that cluster-support bonding induces a polarization of the cluster that could affect reactivity and catalysis. Supported catalysts prepared from precursors with noble metal-oxophilic metal bonds are modeled as clusters of a few atoms of the noble metal ‘nested’ in a supported cluster of the oxophilic metal oxide, which helps to anchor and stabilize the noble metal clusters. Changes in the oxide support have only modest effects on the catalytic activities of supported metal clusters for toluene hydrogenation, but the catalytic activity of γ-Al 2 O 3 -supported Ir clusters per exposed Ir atom increases with increasing cluster size, and this observation remains to be explained.
Mobility and Contact Mechanics of a Rotating Platform Total Knee Replacement

Despite their increasing clinical usage, mobile-bearing total knee replacements have not been well characterized biomechanically. An experimental and finite element analysis was done to asses the mobility and contact mechanics of a widely used rotating platform total knee replacement. Parameters that varied were axial load, condylar load allocation, flexion angle, and static versus dynamic loading. Similar results from the physical model and finite element model lend credence to the validity of the findings. The torque required to initiate rotation (static torque) was greater than that to sustain rotation (dynamic torque). At four times body weight axial load, peak resisting torque measured was 9.47 ± 0.61 and 5.51 ± 0.38 N-m, for static and dynamic torque, respectively. A 60–40 condylar load allocation produced slightly less resisting torque than the 50-50 load. For all practical purposes, the polyethylene insert rotated simultaneously with the femoral component, leading to maintenance of high contact area, desirable behavior clinically. Walking cycle simulations produced a total axial rotation range of motion of 6°. The high frictional torques observed at the mobile interface may explain why a percentage of these mobile-bearings fail to rotate under routine functional load.
Formation of Chiral Solids via a Molecular Building Block Approach

The application of principals of molecular recognition to the design of organic and inorganic solids is leading to remarkable progress in the preparation of porous and chiral materials. A new area of supramolecular complexes is metallamacrocycles, large molecules that are sewn together using metal linkages. Metallacrowns are a member of this class of inorganic complexes. In this article we develop a strategy for the preparation of solids that are chiral using metallacrowns as the centerpiece. First, we introduce the available structure types for these molecules and then proceed to describe some of the physical properties associated with this unique molecular assembly. We demonstrate that chirality can be incorporated simply and inexpensively into these molecules and then we show how the metallacrowns can be used as building blocks to make layered solids with chiral channels. Finally, we assess more general strategies that could be used to engineer truly porous and chiral materials with high metal densities.
Neighborhood Stability in Sender–Receiver Games

Abstract This paper characterizes robust outcomes in sender–receiver games. An equilibrium (a retract) is perturbed message persistent (PMP) if it is the limit (Hausdorff limit) of persistent equilibria (persistent retracts) in perturbed games. In strict common interest games separating equilibria are PMP and message invariant equilibria are not PMP. With partial common interest, there exists a PMP retract which partially separates types and message invariant equilibria are not PMP. Under a rich language condition only partially separating equilibria are PMP in partial common interest games, and there are further results on refinements and games where the sender has a preferred equilibrium. Journal of Economic Literature Classification Numbers: C72, D82.
Benchmarking MILC code with OpenMP and MPI

Abstract A trend in high performance computers that is becoming increasingly popular is the use of symmetric multi-processing (SMP) rather than the older paradigm of MPP. MPI codes that ran and scaled well on MPP machines can often be run on an SMP machine using the vendor's version of MPI. However, this approach may not make optimal use of the (expensive) SMP hardware. More significantly, there are machines like Blue Horizon, an IBM SP with 8-way SMP nodes at the San Diego Supercomputer Center that can only support 4 MPI processes per node (with the current switch). On such a machine it is imperative to be able to use OpenMP parallelism on the node, and MPI between nodes. We describe the challenges of converting MILC MPI code to using a second level of OpenMP parallelism, and benchmarks on IBM and Sun computers.
Application of vacuum deposition methods to solid oxide fuel cells

The application of vacuum deposition techniques to the fabrication of solid oxide fuel cell (SOFC) materials and structures are reviewed, focusing on magnetron sputtering, vacuum plasma methods, laser ablation, and electrochemical vapor deposition. A description of each method and examples of use to produce electrolytes, electrodes, and/or electrical interconnects are given. Generally high equipment costs and relatively low deposition rates have limited the use of vacuum deposition methods in SOFC manufacture, with a few notable exceptions. Vacuum methods are particularly promising in the fabrication of micro-fuel cells, where thin films of high quality and unusual configuration are desired.
Electronic signature of DNA nucleotides via transverse transport

We report theoretical studies of charge transport in single-stranded DNA in the direction perpendicular to the backbone axis. We find that, if the electrodes which sandwich the DNA have the appropriate spatial width, each nucleotide carries a unique signature due to the different electronic and chemical structure of the four bases. This signature is independent of the nearest-neighbor nucleotides. Furthermore, except for the nucleotides with guanine and cytosine bases, we find that the difference in conductance of the nucleotides is large for most orientations of the bases with respect to the electrodes. By exploiting these differences it may be possible to sequence single-stranded DNA by scanning its length with conducting probes.
Neo‐pentoxide Precursors for MOCVD Thin Films of TiO2 and ZrO2

Two group IV precursors, titanium(IV) neo-pentoxide, [Ti(μ-ONep)(ONep) 3 ] 2 (1, where ONep = OCH 2 C(CH 3 ) 3 ), and zirconium(IV) neo-pentoxide, [Zr(μ-ONep)(ONep) 3 ] 2 (2), were found to possess relatively high volatility at low temperatures. These compounds were therefore investigated as metal-organic CVD (MOCVD) precursors using a lamp-heated cold-wall CVD reactor by direct vaporization without a carrier gas. The ONep derivatives proved to be competitive precursors for the production of thin films of the appropriate MO 2 (M = Ti or Zr) materials in comparison to other metallo-organic precursors. Compound 1 was found to vaporize at 120 °C with a deposition rate of -0.350 μm/min onto a substrate at 330 °C forming the anatase phase with <1 % residual C found in the final film. Compound 2 was found to vaporize at 160 °C and deposited a crystalline material at 300 °C with <1 % residual C found in the final film. A comparison with standard alkoxide and β-diketonates is presented where appropriate.
Application of the 4-trifluoromethylbenzenepropargyl ether group as an unhindered, electron deficient protecting group for stereoselective glycosylation.

4-Trifluoromethylbenzenepropargyl ethers are stable and sterically minimal alcohol protecting groups that are readily cleaved in a single step by exposure to lithium naphthalenide. In conjunction with the 4,6-O-benzylidene protecting group, glycosylation reactions of 2-O-(4-trifluoromethylbenzenepropargyl)-protected mannosyl donors are extremely β-selective.
On compact and efficient routing in certain graph classes

In this paper we refine the notion of tree-decomposition by introducing acyclic (R,D)-clustering, where clusters are subsets of vertices of a graph and R and D are the maximum radius and the maximum diameter of these subsets. We design a routing scheme for graphs admitting induced acyclic (R,D)-clustering where the induced radius and the induced diameter of each cluster are at most 2. We show that, by constructing a family of special spanning trees, one can achieve a routing scheme of deviation @D=<2R with labels of size O(log^3n/loglogn) bits per vertex and O(1) routing protocol for these graphs. We investigate also some special graph classes admitting induced acyclic (R,D)-clustering with induced radius and diameter less than or equal to 2, namely, chordal bipartite, homogeneously orderable, and interval graphs. We achieve the deviation @D=1 for interval graphs and @D=2 for chordal bipartite and homogeneously orderable graphs.
Internet Casinos: A Sure Bet for Money Laundering

Since the end of the Second World War, American society has seen the emergence of technology promising to make life easier, better and longer lasting. The more recent explosion of the Internet is fulfilling the dreams of the high‐tech pundits as it provides global real‐time communication links and makes the world's knowledge universally available. Privacy concerns surrounding the development of the Internet have mounted, and in response, service providers and website operators have enabled Web users to conduct transactions in nearly complete anonymity. While anonymity respects individual privacy, it also facilitates criminal activities needing secrecy. One such activity is money laundering, which is now being facilitated by the emerging Internet casinos industry. These casinos can be physically located anywhere with websites available worldwide. Internet casinos were a target of legislation by the US Congress, but the legislation, the Internet Gambling Prohibition Act, failed to pass. So, at the moment, Internet casinos are a virtually unregulated mechanism for laundering illegal funds.
Site limitations on Solar Sea Power Plants

S operation of a Solar Sea Power Plant (SSPP) requires that the warm water intake draws water only from the top mixed layer of the ocean. This requirement places an upper limit Qmax, upon the warm water intake. In this paper, Qmax is calculated as a function of thickness of the upper mixed layer, the ocean current velocity, and the site latitude. Typically, this upper limit corresponds to a maximum electrical power output of some thousands of megawatts.
Elliptic-Hyperbolic Systems and the Einstein Equations

The Einstein evolution equations are studied in a gauge given by a combination of the constant mean curvature and spatial harmonic coordinate conditions. This leads to a coupled quasi-linear elliptic-hyperbolic system of evolution equations. We prove that the Cauchy problem is locally strongly well posed and that a continuation principle holds.¶For initial data satisfying the Einstein constraint and gauge conditions, the solutions to the elliptic-hyperbolic system defined by the gauge fixed Einstein evolution equations are shown to give vacuum space-times.
Compton scattered transition radiation from very high energy particles

Abstract X-ray transition radiation can be used to measure the Lorentz factor of relativistic particles. At energies approaching γ = E / mc 2 =10 5 , transition radiation detectors can be optimized by using thick (∼5–10 mil) foils with large (∼5–10 mm) spacings. This implies X-ray energies ≳100 keV and the use of scintillators as the X-ray detectors. Compton scattering of the X-rays out of the particle beam then becomes an important effect. We discuss the design of very high energy detectors, the use of metal radiator foils rather than the standard plastic foils, inorganic scintillators for detecting Compton scattered transition radiation, and the application to the ACCESS cosmic ray experiment.
Ion density deviations in semipermeable ionic microcapsules

By implementing the nonlinear Poisson-Boltzmann theory in a cell model, we theoretically investigate the influence of polyelectrolye gel permeability on ion densities and pH deviations inside the cavities of ionic microcapsules. Our calculations show that variations in permeability of a charged capsule shell cause a redistribution of ion densities within the capsule, which ultimately affects the pH deviation and Donnan potential induced by the electric field of the shell. We find that semipermeable capsules can induce larger pH deviations inside their cavities that can permeable capsules. Furthermore, with increasing capsule charge, the influence of permeability on pH deviations progressively increases. Our theory, while providing a self-consistent method for modeling the influence of permeability on fundamental properties of ionic microgels, makes predictions of practical significance for the design of microcapsules loaded with fluorescent dyes, which can serve as biosensors for diagnostic purposes.
Multi-personality partitioning for heterogeneous systems

Design flows use graph partitioning both as a precursor to place and route for single devices, and to divide netlists or task graphs among multiple devices. Partitioners have accommodated FPGA heterogeneity via multi-resource constraints, but have not yet exploited the corresponding ability to implement some computations in multiple ways (e.g., LUTs vs. DSP blocks), which could enable a superior solution. This paper introduces multi-personality graph partitioning, which incorporates aspects of resource mapping into partitioning. We present a modified multi-level KLFM partitioning algorithm that also performs heterogeneous resource mapping for nodes with multiple potential implementations (multiple personalities). We evaluate several variants of our multi-personality FPGA circuit partitioner using 21 circuits and benchmark graphs, and show that dynamic resource mapping improves cut size on average by 27% over static mapping for these circuits. We further show that it improves deviation from target resource utilizations by 50% over post-partitioning resource mapping.
The load rebalancing problem

In the classical load balancing or multiprocessor scheduling problem, we are given a sequence of jobs of varying sizes and are asked to assign each job to one of the m empty processors. A typical objective is to minimize the makespan, which is the load on the heaviest loaded processor. Since in most real world scenarios the load is a dynamic measure, the initial assignment may not remain optimal over time. Motivated by such considerations in a variety of systems, we formulate the problem of load rebalancing--given a possibly suboptimal assignment of jobs to processors, relocate a set of the jobs so as to decrease the makespan. Specifically, the goal is to achieve the best possible makespan under the constraint that no more than k jobs are relocated. We also consider the weighted version of this problem where there is an arbitrary cost associated with each job's relocation. The problem is NP-hard and hence, we focus on approximation algorithms. We construct an algorithm which achieves a 1.5-approximation, with near linear running time. We also show that the problem has a PTAS, thereby resolving the complexity issue. Finally, we investigate the approximability of several extensions of the load rebalancing model.
Total synthesis of (-)-stemonine.

An enantioselective total synthesis of (−)-stemonine (1) is reported via a convergent assembly of the acyclic precursor 2. Key transformations include a Staudinger−aza-Wittig reaction to form the central perhydroazepine ring system and an iodine-induced tandem cyclization to construct the pyrrolidino-butyrolactone framework.
Low-velocity impact damage initiation in graphite/epoxy/Nomex honeycomb-sandwich plates

Abstract Low-velocity impact and static indentation tests on sandwich plates composed of 4- to 48-ply graphite/epoxy cross-ply laminate facesheets and Nomex honeycomb cores have been performed to characterize damage initiation as a function of facesheet thickness and loading rate. Force histories during low-velocity impact are measured by using an instrumented impactor and integrated to produce energy histories. Energy histories are shown to reveal damage initiation. Static indentation tests show damage that is similar to that produced by low-velocity impact. The force at which damage initiates is shown to be lower for static tests than for low-velocity impact tests, and differences between equilibrium curves for the two types of loading are discussed. The difference between static and low-velocity impact tests is greater for plates with thicker facesheets. This may indicate a limitation of the applicability of the common assumption that low-velocity impact is a quasi-steady process.
Memory and anxiety disorders

Experimental psychopathologists have identified varying patterns in memory bias in people with depressive and anxiety disorders. Individuals suffering from depression tend to exhibit explicit memory deficits for positively-valanced material, and sometimes exhibit biases for retrieving negative self-relevant information as well. Most studies, however, provide scant evidence for implicit memory biases in depression. In contrast to depression, anxiety disorders are rarely associated with enhanced esplicit memory for threat-related information (with the exception of panic disorder). Evidence for implicit memory biases for threat in these syndromes is mixed. After providing an overview of findings on memory abnormalities in depressive and anxiety disorders, data from several new studies bearing on posttraumatic stress disorder (PTSD) in Vietnam combat veterans and in women with histories of childhood sexual abuse are presented. Involving directed forgetting, implicit memory and autobiographical cueing paradigms, these experiments point to a pattern of abnormalities linked to PTSD rather than to trauma per se.
From information to exact communication

We develop a new local characterization of the zero-error information complexity function for two-party communication problems, and use it to compute the exact internal and external information complexity of the 2-bit AND function: IC(AND,0) = C∧≅ 1.4923 bits, and ICext(AND,0) = log2 3 ≅ 1.5839 bits. This leads to a tight (upper and lower bound) characterization of the communication complexity of the set intersection problem on subsets of {1,...,n} (the player are required to compute the intersection of their sets), whose randomized communication complexity tends to C∧⋅ n pm o(n) as the error tends to zero.The information-optimal protocol we present has an infinite number of rounds. We show this is necessary by proving that the rate of convergence of the r-round information cost of AND to IC(AND,0)=C∧ behaves like Θ(1/r2), i.e. that the r-round information complexity of AND is C∧+Θ(1/r2).We leverage the tight analysis obtained for the information complexity of AND to calculate and prove the exact communication complexity of the set disjointness function Disjn(X,Y) = - vi=1n AND(xi,yi) with error tending to 0, which turns out to be = CDISJ⋅ n pm o(n), where CDISJ≅ 0.4827. Our rate of convergence results imply that an asymptotically optimal protocol for set disjointness will have to use ω(1) rounds of communication, since every r-round protocol will be sub-optimal by at least Ω(n/r2) bits of communication.We also obtain the tight bound of 2/ln2 k pm o(k) on the communication complexity of disjointness of sets of size ≤ k. An asymptotic bound of Θ(k) was previously shown by Hastad and Wigderson.
Magnetic fluffy dark matter

We explore extensions of inelastic Dark Matter and Magnetic inelastic Dark Matter where the WIMP can scatter to a tower of heavier states. We assume a WIMP mass m χ ~ $ \mathcal{O} $ (1-100) GeV and a constant splitting between successive states δ ~ $ \mathcal{O} $ (1-100) keV. For the spin-independent scattering scenario we find that the direct experiments CDMS and XENON strongly constrain most of the DAMA/LIBRA preferred parameter space, while for WIMPs that interact with nuclei via their magnetic moment a region of parameter space corresponding to m χ ~ 11 GeV and δ < 15 keV is allowed by all the present direct detection constraints.
Public Investment in Rural Infrastructure: Some Political Economy Considerations

We have constructed a unique dataset to study the extent of the relationship between political marginalisation, public investment in transport infrastructure, and food security in Benin, Ghana, Mali and Senegal. We first show a strong relation between food security and road infrastructures after controlling for other factors known to affect food security, including climate and land productivity. To trace a potential mechanism by which political marginalisation impacts on food security, we then look at its relation with the allocation of roads within countries. We find support for the argument that political factors affect the location of roads after controlling for the economic importance of the areas, as well as many other factors. This finding is robust to a number of alternative specifications. We conclude that politically marginalised areas have significantly fewer roads, thus supporting our claim that political marginalisation indirectly affects food security, by undermining the quality and the allocation of transport infrastructures. Although we do not establish a causal effect here, this study is the first to empirically substantiate this relationship at the micro-level. Copyright 2013 , Oxford University Press.
A Note on the Simplification of Fuzzy Switching Functions

Abstract This note is concerned with the modification of the definition of fuzzy consensus. The modified version is used to find the set of all fuzzy prime implicants of a fuzzy switching function as defined previously. The fuzzy algebra used to derive these functions satisfies the set of axioms of a distributive lattice with unique identities under the operators of maximum and minimum as described earlier.
Reduced rank regression via adaptive nuclear norm penalization

We propose an adaptive nuclear norm penalization approach for low-rank matrix approximation, and use it to develop a new reduced rank estimation method for high-dimensional multivariate regression. The adaptive nuclear norm is defined as the weighted sum of the singular values of the matrix, and it is generally non-convex under the natural restriction that the weight decreases with the singular value. However, we show that the proposed non-convex penalized regression method has a global optimal solution obtained from an adaptively soft-thresholded singular value decomposition. The method is computationally efficient, and the resulting solution path is continuous. The rank consistency of and prediction/estimation performance bounds for the estimator are established for a high-dimensional asymptotic regime. Simulation studies and an application in genetics demonstrate its efficacy.
Is Democratic Theory for Export

A prominent feature of American political consciousness is a desire to propagate democracy throughout the world. In our enthusiasm to share what we enjoy, Jacques Barzun sees that little attention is paid to exactly what we are trying to distribute. Through a brief historical survey of democracy, he shows that our popular conception of the term does not correspond with any particular definition. U.S. democracy has no central text and is distinctly different, in theory and in practice, from the democracy of other states, both historical and contemporary. Democracy is an abstract ideal that is a function of time. Its present incarnation in the United States emphasizes freedom and equality through the means and language of specific personal rights. Barzun sees an internal tension in this formulation, one that ultimately threatens both freedom and equality if exported to the rest of the world.
A Rapid DNA Hybridization Assay for the Evaluation of Antiviral Compounds Against Epstein-Barr Virus

There is a need for additional therapies for Epstein-Barr virus (EBV) infections, but the routine screening of large numbers of potential inhibitors has been difficult due to the laborious nature of traditional assays. A new rapid assay was developed to evaluate compounds for antiviral activity against this virus that is both rapid and robust. Test compounds are added to cultures of Akata cells in 96-well plates that have been induced to undergo a lytic infection. Viral DNA produced during the infection is transferred to a membrane and quantified using a non-radioactive DNA hybridization assay. This assay was validated using a set of compounds with known activity against EBV and results compared favorably to an established real-time PCR assay. Subsequent experience with this assay has confirmed that it offers improved efficiency and robustness compared to other assays used routinely to evaluate candidate compounds for antiviral activity against EBV.
A comparative study of numerical methods of elastic-plastic analysis.

WO general methods have been developed for the elasticplastic analysis of continuous solid bodies. The method of "thermal" or "initial strains"1 is based on the idea of modifying the elastic equations of equilibrium to compensate for the fact that the plastic strains do not cause any change in stress. On the other hand, the tangent modulus method2 is based on the linearity of the incremental laws of plasticity. The load is applied in increments, and at each stage, a new set of coefficients are obtained for the equilibrium equations. Both methods have been used in conjunction with finite element theory. The matrix equations for finite element analysis using the method of initial strains were developed in Refs. 3-5, whereas the equations for the tangent modulus method were developed in Refs. 6-8. Since both methods solve the same problem, there should be a close relation between them, and perhaps a comparison could lead to a better understanding of the original problem. This note addresses itself to such a comparison. II. Elastic-Plastic Stress-Strain Relations The linear relation between the increments of stress and strain developed in Marcal and King8 is taken here as the point of departure. With the definition of the elastic components of the strain increments,
When will we detect the extraterrestrials

Abstract It has been more than four decades since the first, modern SETI experiment. Many hundreds of star systems have been observed in the radio over wide bandwidth and with impressive sensitivity, and the entire sky has been surveyed in a more restricted mode several times. Optical SETI experiments are underway, and have already scrutinized several thousand nearby stars, looking for nanosecond light pulses. Still, there is no confirmed signal detection. Given the anticipated improvement in both telescopes and digital electronics applied to SETI, what is the time scale for making such a discovery? In this paper we investigate the rate of stellar surveillance by targeted radio SETI experiments for the foreseeable future, and conclude that it is likely that—if the principal assumptions underlying modern SETI are reasonable—a detection will occur within a single generation.
A Sine Galvanometer for Determining in Absolute Measure the Horizontal Intensity of the Earth's Magnetic Field

A brief historical statement was made with reference to the measurement of the horizontal intensity of the earth's magnetic field by electrical methods, and a general description of sine and tangent galvanometers was given, with the suggestion of an improvement in the latter. Then followed a detailed description of a new sine galvanometer, constructed, with certain exceptions mentioned below, in the workshop of the Department of Terrestrial Magnetism. The base of the instrument, including the tripod, circles, etc, was taken from one of Wild's theodolites, constructed by Edelmann, and was much improved by the substitution of non-magnetic parts for parts too magnetic, and by the substitution of electrical illumination of the precision circle for daylight illumination by mirrors.
Use of GPO bookstores

Abstract The U.S. Government Printing Office opened its first retail bookstore outside the Washington, D.C. area in 1967. There are now 27 sales outlets operating across the United States, the latest of which was opened in Pittsburgh in the latter part of 1979. This article briefly overviews the bookstore program and provides a case study of the Boston bookstore, its collection and clientele. In addition, it suggests topics for further investigation.
Metal-Free Chlorodeboronation of Organotrifluoroborates

A mild and metal-free method for the chlorodeboronation of organotrifluoroborates using trichloroisocyanuric acid (TCICA) was developed. Aryl-, heteroaryl-, alkenyl-, alkynyl-, and alkyltrifluoroborates were converted into the corresponding chlorinated products in good yields. This method proved to be tolerant of a broad range of functional groups.
Substituent Effects on Non‐Covalent Interactions with Aromatic Rings: Insights from Computational Chemistry

Non-covalent interactions with aromatic rings pervade modern chemical research. The strength and orientation of these interactions can be tuned and controlled through substituent effects. Computational studies of model complexes have provided a detailed understanding of the origin and nature of these substituent effects, and pinpointed flaws in entrenched models of these interactions in the literature. Here, we provide a brief review of efforts over the last decade to unravel the origin of substituent effects in π-stacking, XH/π, and ion/π interactions through detailed computational studies. We highlight recent progress that has been made, while also uncovering areas where future studies are warranted.
DARK MATTER HALOS AND EVOLUTION OF BARS IN DISK GALAXIES: VARYING GAS FRACTION AND GAS SPATIAL RESOLUTION

We conduct numerical experiments by evolving gaseous/stellar disks embedded in live dark matter halos aiming at quantifying the effect of gas spatial resolution and gas content on the bar evolution. Three model sequences have been constructed using different resolutions, and the gas fraction has been varied along each sequence within the range of f g = 0%-50%, but keeping the disk and halo properties unchanged. We find that the spatial resolution becomes important with an increase in the gas content. For the higher resolution model sequences, we observe a bimodal behavior in the bar evolution with respect to the gas fraction, especially during the secular phase of this evolution. The switch from the gas-poor to gas-rich behavior is abrupt and depends on the resolution used, being reasonably confined to f g ~ 5%-12%. The diverging evolution has been observed in nearly all basic parameters characterizing bars, such as the bar strength, central mass concentration, bar vertical buckling amplitude, bar size, etc. We find that the presence of the gas component severely limits the bar growth and affects its pattern speed evolution. Gas-poor models display rapidly decelerating bars, while gas-rich models exhibit bars with constant or even slowly accelerating tumbling. We also find that the gas-rich models have bar corotation (CR) radii within the disk at all times, in contrast with gas-poor and purely stellar disks. In addition, the CR-to-bar size ratio is less than 2 for gas-rich models. Next, we have confirmed that the disk angular momentum within the CR remains unchanged in the gas-poor models, as long as the CR stays within the disk, but experiences a sharp drop before leveling off in the gas-rich models. Finally, we discuss a number of observed correlations between various parameters of simulated bars, such as between the bar sizes and the gas fractions, between the bar strength and the buckling amplitude, and between the bar strength and its size, etc.
Degrees of freedom and model search

Degrees of freedom is a fundamental concept in statistical modeling, as it provides a quantitative description of the amount of fitting performed by a given procedure. But, despite this fundamental role in statistics, its behavior is not completely well-understood, even in somewhat basic settings. For example, it may seem intuitively obvious that the best subset selection fit with subset size k has degrees of freedom larger than k, but this has not been formally verified, nor has is been precisely studied. At large, the current paper is motivated by this problem, and we derive an exact expression for the degrees of freedom of best subset selection in a restricted setting (orthogonal predictor variables). Along the way, we develop a concept that we name “search degrees of freedom”; intuitively, for adaptive regression procedures that perform variable selection, this is a part of the (total) degrees of freedom that we attribute entirely to the model selection mechanism. Finally, we establish a modest extension of Stein’s formula to cover discontinuous functions, and discuss its potential role in degrees of freedom and search degrees of freedom calculations.
Stress Tensors in p-adic String Theory and Truncated OSFT

We construct the stress tensors for the p-adic string model and for the pure tachyonic sector of open string field theory by naive metric covariantization of the action. Then we give the concrete energy density of a lump solution of the p-adic model. In the cubic open bosonic string field theory, we also give the energy density of a lump solution and pressure evolution of a rolling tachyon solution.
Branes, orientifolds and the creation of elementary strings

Abstract The potential of a configuration of two Dirichlet branes for which the number of ND-directions is eight is determined. Depending on whether one of the branes is an anti-brane, the potential vanishes or is twice as large as the dilaton-gravitational potential. This is shown to be related to the fact that a fundamental string is created when two such branes cross. Special emphasis is given to the D0–D8 system, for which an interpretation of these results in terms of the massive IIA supergravity is presented. It is also shown that the branes cannot move non-adiabatically in the transverse direction. The configuration of a zero-brane and an orientifold 8-plane is analyzed in a similar way, and the implications for the type IA-heterotic duality and the heterotic matrix theory are discussed.
Electric-Field Induced Formation of Superconducting Granular Balls

When a strong electric field is applied to a suspension of micron-sized high Tc superconducting particles in liquid nitrogen, the particles quickly aggregate together to form millimeter-size balls. The balls are sturdy, surviving constant heavy collisions with the electrodes, while they hold over 106 particles each. The phenomenon is a result of interaction between Cooper pairs and the strong electric field. The strong electric field induces surface charges on the particle surface. When the applied electric field is strong enough, Cooper pairs near the surface are depleted, leading to a positive surface energy. The minimization of this surface energy leads to the aggregation of particles to form balls.
Directional free-space coupling from photonic crystal waveguides

We present a general approach for coupling a specific mode in a planar photonic crystal (PC) waveguide to a desired free-space mode. We apply this approach to a W1 PC waveguide by introducing small index perturbations to selectively couple a particular transverse mode to an approximately Gaussian, slowly diverging free space mode. This "perturbative photonic crystal waveguide coupler" (PPCWC) enables efficient interconversion between selectable propagating photonic crystal and free space modes with minimal design perturbations.
All-optical switching of photonic entanglement

Future quantum optical networks will require the ability to route entangled photons at high speeds, with minimal loss and added in-band noise, and?most importantly?without disturbing the photons' quantum state. Here we present an all-optical switch that fulfills these requirements and characterize its performance at the single-photon level. It exhibits a 200?ps switching window, 120?:?1 contrast, 1.5?dB loss, and induces no measurable degradation in the switched photons' entangled-state fidelity (<0.002). As a proof-of-principle demonstration of its capability, we use the switch to demultiplex a single quantum channel from a dual-channel, time-division-multiplexed entangled photon stream. Furthermore, because this type of switch couples the temporal and spatial degrees of freedom, it provides an important new tool with which to encode multiple-qubit quantum states on a single photon.
Histologic precursors of gastrointestinal tract malignancy

The term ‘‘precursor lesion’’ describes the gross and histologic changes that precede the development of cancer. This term is preferred to others such as ‘‘precancerous’’ or ‘‘premalignant’’ because it does not imply inevitable progression of the lesion to cancer. In contrast, ‘‘precursor conditions’’ are those disease states that are associated with an increased risk for the development of cancer. All precursor lesions in the gastrointestinal tract (GIT) exhibit dysplasia. Dysplasia literally means a disorganized growth, and is used to describe nonneoplastic and preneoplastic lesions elsewhere in the body. In contrast, dysplasia in the GIT is defined as an ‘‘unequivocally neoplastic proliferation’’ confined to the basement membrane. Therefore, precursor lesion, dysplastic lesion, intraepithelial neoplasia, and benign neoplasm are synonyms in the GIT. The caveat is that on occasion, morphologic changes that we recognize as dysplasia can be seen in association with an underlying invasive carcinoma, akin to finding an adenocarcinoma arising within an adenoma. Alternatively, the superficial aspect of a well differentiated carcinoma may be misinterpreted as dysplasia. Thus, interpretation of biopsies from a large dysplastic lesion should include a comment that an underlying carcinoma cannot be excluded on the basis of a representative sample alone. The establishment of dysplasia as a precursor to invasive cancer, also referred to as the adenoma–carcinoma continuum, is based on multiple lines of evidence including studies that show that dysplastic lesions precede the development of cancer and removal of dysplastic lesions decreases cancer risk. In addition, dysplastic lesions are present with increased frequency in individuals with hereditary cancer syndromes. Morphologic evidence includes the finding of carcinoma arising within a dysplastic lesion and residual dysplasia juxtaposed to adenocarcinoma. Molecular studies of neoplasia have validated these obser
Quasiflats with holes in reductive groups

We give a new proof of a theorem of Kleiner-Leeb: that any quasi-isometrically embedded Euclidean space in a product of symmetric spaces and Euclidean buildings is contained in a metric neighborhood of finitely many flats, as long as the rank of the Euclidean space is not less than the rank of the target. A bound on the size of the neighborhood and on the number of flats is determined by the size of the quasi-isometry constants. Without using asymptotic cones, our proof focuses on the intrinsic geometry of symmetric spaces and Euclidean buildings by extending the proof of Eskin-Farb's quasiflat with holes theorem for symmetric spaces with no Euclidean factors.
Synthesis of Acyclonucleoside Phosphonates as Antiviral Agents Against Cytomegalovirus

Abstract Phosphonic acid analogs of ACV and DHPG that are isosteric with ACV phosphate and DHPG phosphate have been synthesized and evaluated for antiviral activity against human, murine, and guinea pig strains of cytomegalovirus. The phosphonates showed high activity against all of the strains. They were also evaluated against a DHPG resistant strain of human cytomegalovirus. Although the activity dropped considerably, significant antiviral activity was still evident.
Dual-Pathway Kinetic Equation for the Hydrogen Oxidation Reaction on Pt Electrodes

In the past 2 years, several experimental observations and theoretical studies indicated that the commonly used Butler-Volmer equation was inappropriate for describing the kinetics of the hydrogen oxidation reaction (HOR) on a Pt electrode. Motivated by these works, we developed an HOR kinetic equation from a dual-pathway model to describe the complex kinetic behavior over the whole relevant potential region. A simple expression was found for the reaction intermediate's coverage as a function of overpotential. Three intrinsic kinetic parameters were determined by analyzing published polarization curves measured with microelectrodes (high mass transport) and rotating disk electrodes (relatively low mass transport, high accuracy). The results show a fast, inversed exponential rising of kinetic current at small overpotentials through the Tafel-Volmer pathway, and a much more gradual rise at η > 50 mV through the Heyrovsky-Volmer pathway. This behavior is dramatically different from the single-exponential increase of the Butler-Volmer equation. The puzzling dependence of anode overpotential on Pt loading in H 2 -fed proton-exchange membrane fuel cells can now be explained by the dual-pathway kinetic equation, providing a sound basis for fuel cell modeling, optimization, and diagnosis. The principle and approach used in this study can be applied to other electrocatalytic reactions.
Toward catalysis in the 21st century chemical industry

Abstract The general public is becoming much more concerned over environmental issues, and decisions are being made that are not necessarily based on science. For the chemical industry it is becoming increasingly difficult to obtain permits, eliminate waste, construct incinerators and receive and ship toxic materials. The effect will clearly increase the relative importance of environmental vs. variable costs for current and future plants. As a result, the following will become increasingly important: processes with 100% yield (by whatever process); catalyst recovery, regeneration and recycle; heterogenization of homogeneous catalysts; increasing importance of chiral pharmaceutical and agrichemicals; polymer recycle and environmentally safer processes. Several of these aspects, from DuPont R&D will be highlighted in this paper.
Detection of the 3.4 micron emission feature in comets P/Brorsen-Metcalf and Okazaki-Levy-Rudenko (1989r) and an observational summary

The 3.4 micron emission feature due to cometary organics was detected in Comets P/Brorsen-Metcalf and Okazaki-Levy-Rudenko (1989r). Features-to-continuum ratios in these two comets were higher than those expected from the trend seen in other comets to date. Three micron spectra of eight comets are reviewed. The 3.4 micron band flux is better correlated with the water production rate than with the dust production rate in this sample of comets. High feature-to-continuum ratios in P/Brorsen-Metcalf and Okazaki-Levy-Rudenko can be explained by the low dust-to-gas ratios of these two comets. The observations to date are consistent with cometary organics being present in all comets (even those for which no 3.4 micron feature was evident) at comparable abundances with respect to water. The emission mechanism and absolute abundance of the organics are not well determined; either gas-phase fluorescence or thermal emission from hot grains is consistent with the heliocentric distance dependence of the 3.4 micron band flux. There is an overall similarity in the spectral profiles of the 3.4 micron feature in comets; however, there are some potentially significant differences in the details of the spectra.
The empirical status of job search theory

Abstract This brief paper summarizes — without detail — the results of an extensive review of empirical labor economics in the search framework [Devine and Keifer (1991)].
Double Auctions for Dynamic Spectrum Allocation

Wireless spectrum is a precious resource and must be allocated and used efficiently. Conventional spectrum allocations let a government agency (e.g., FCC) sell a portion of spectrum to one provider. This is not only restrictive, but also limits spectrum reuse and may lead to significant under-utilization of spectrum. In this paper, we develop a novel truthful double-auction scheme to let any resource owner (e.g., a cellular provider), who has spare spectrum at a given time period, sell to one or more providers that need additional spectrum at that time. Spectrum auctions are fundamentally different from conventional auction problems since spectrum can be reused and competition among buyers is complex due to wireless interference. Our proposal is the first double-auction design for spectrum allocation that explicitly decouples the buyer-side and seller-side auction design while achieving: 1) truthfulness; 2) individual rationality; and 3) budget-balance. To accurately capture wireless interference and support spectrum reuse, we partition the conflict graph so that buyers with strong direct and indirect interference are put into the same subgraph, and buyers with no interference or weak interference are put into separate subgraphs. Then, we compute pricing independently within each subgraph. We then develop a scheme to combine spectrum allocation results from different subgraphs and resolve potential conflicts. We further extend our approach to support local sellers whose spectrum can only be sold to buyers within certain regions, instead of all buyers. Using conflict graphs generated from real cell tower locations, we extensively evaluate our approach and demonstrate that it achieves high efficiency, revenue, and utilization.
The importance of faith: Tax morale and religiosity

The intention of this paper is to analyze religiosity as a factor that potentially affects tax morale. For this purpose, a multivariate analysis has been done with data from the World Values Survey 1995–1997, covering more than 30 countries at the individual level. Several variables, such as church attendance, religious education, active membership in a church or a religious organization, perceived religiosity, religious guidance and trust in the church have been analyzed. The results suggest that religiosity raises tax morale.
Radiation from the non-extremal fuzzball

The fuzzball proposal says that the information of the black hole state is distributed throughout the interior of the horizon in a 'quantum fuzz'. There are special microstates where in the dual CFT we have 'many excitations in the same state'; these are described by regular classical geometries without horizons. Jejjala et al (2005 Phys. Rev. D 71 124030) constructed non-extremal regular geometries of this type. Cardoso et al (2006 Phys. Rev. D 73 064031, 2007 Phys. Rev. D 76 105015) then found that these geometries had a classical instability. In this paper, we show that the energy radiated through the unstable modes is exactly the Hawking radiation for these microstates. We do this by (i) starting with the semiclassical Hawking radiation rate, (ii) using it to find the emission vertex in the CFT, (iii) replacing the Boltzman distributions of the generic CFT state with the ones describing the microstate of interest, (iv) observing that the emission now reproduces the classical instability. Because the CFT has 'many excitations in the same state' we get the physics of a Bose–Einstein condensate rather than a thermal gas, and the usually slow Hawking emission increases, by Bose enhancement, to a classically radiated field. This system therefore provides a complete gravity description of information-carrying radiation from a special microstate of the non-extremal hole.