cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanistic and kinetic studies of NOx storage and reduction on Pt/BaO/Al2O3

NOx storage and NO oxidation experiments have been carried out on a model Pt/BaO/Al2O3 catalyst powder in order to elucidate kinetic and thermodynamic limitations. Uptake of NO on a pre-oxidized catalyst reveals the existence of multiple regimes. The short-term storage is a sensitive function of storage time, but is nearly independent of temperature whereas the long-time storage has much slower kinetics and is a non-monotonic function of temperature. A simple steady-state reactor model is developed that predicts NO oxidation conversion and the limiting NOx storage. The model predicts that full barium utilization is thermodynamically feasible even under kinetically limiting conditions of incomplete NO oxidation. However, apparent NOx diffusion limitations prevent complete utilization. Storage and reduction (with propylene) experiments indicate that less than 10% of the barium is needed to achieve high NOx conversion (>85%) at moderate space velocity. At higher temperature both NO oxidation and barium nitrate formation are thermodynamically limited, both of which adversely impact the NOx reduction. Thermogravimetric measurements corroborate a physical picture in which only a small fraction of barium is utilized during lean/rich cycling protocols giving high NOx conversion.
Graphene and Graphene Oxide: Synthesis, Properties, and Applications

There is intense interest in graphene in fields such as physics, chemistry, and materials science, among others. Interest in graphene's exceptional physical properties, chemical tunability, and potential for applications has generated thousands of publications and an accelerating pace of research, making review of such research timely. Here is an overview of the synthesis, properties, and applications of graphene and related materials (primarily, graphite oxide and its colloidal suspensions and materials made from them), from a materials science perspective.
Symplectic embeddings and continued fractions : a survey

As has been known since the time of Gromov’s Non-squeezing Theorem, symplectic embedding questions lie at the heart of symplectic geometry. After surveying some of the most important ways of measuring the size of a symplectic set, these notes discuss some recent developments concerning the question of when a 4-dimensional ellipsoid can be symplectically embedded in a ball. This problem turns out to have unexpected relations to the properties of continued fractions and of exceptional curves in blow ups of the complex projective plane. It is also related to questions of lattice packing of planar triangles.
Stereo image compression based on disparity field segmentation

The increasing demand for 3D imaging and recent developments of autostereoscopic displays will accelerate the usage of 3D systems in various areas. However, limited channel bandwidth is, as for monocular images, the main bottleneck for realizing 3D systems. As a result, an efficient compression algorithm will be essential to reduce the bandwidth requirement while maintaining the perceptual visual quality at the decoder. In this paper, we will focus on compression of stereo images. When it comes to stereo image coding, we can take advantage of binocular redundance by using disparity compensation. The most popular disparity compensation method approaches so far have ben block based methods, due mostly to their simplicity. Block based methods, however, may suffer from blocking artifacts at low bit rates due to the uniform disparity assumption within a fixed block. Meanwhile, if we reduce the block size, the disparity estimation may suffer from various noise effects which result in increases of bit rates for the disparity. Considering these observations, we estimate disparity based on a small block or a pixel with thee energy equation derived from the MRF model. In order to prevent oversmoothing across boundaries, we use the combined intensity edges of two images as an initial disparity boundary. Then, we segment the resulting smooth disparity field. Finally, the disparity and the starting position are encoded using DPCM and the corresponding boundary is encoded using Run Length Chain coding. At the end of this paper, we present experimental results.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Tractable State-Space Model for Symmetric Positive-Definite Matrices

The Bayesian analysis of a state-space model includes computing the posterior distribution of the system’s parameters as well as its latent states. When the latent states wander around Rn there are several well-known modeling components and computational tools that may be profitably combined to achieve this task. When the latent states are constrained to a strict subset of Rn these models and tools are either impaired or break down completely. State-space models whose latent states are covariance matrices arise in finance and exemplify the challenge of devising tractable models in the constrained setting. To that end, we present a state-space model whose observations and latent states take values on the manifold of symmetric positive-definite matrices and for which one may easily compute the posterior distribution of the latent states and the system’s parameters as well as filtered distributions and one-step ahead predictions. Employing the model within the context of finance, we show how one can use realized covariance matrices as data to predict latent time-varying covariance matrices. This approach out-performs factor stochastic volatility.
Synthesis of Butyronitrile via Ammonolysis of Butylalcohol and Dehydrogenation of Butylamine over Mo2N

Investigations were carried out of the synthesis of butyronitrile via the ammonolysis of butylalcohol and the dehydrogenation of butylamine over Mo[sub 2]N. At 573 K butyronitrile is produced with virtually 100% yielded by both reactions. The ammonolysis of butylalcohol proceeds via dehydrogenation of the butylalcohol to form butyraldehyde, which then reacts with ammonia to produce butylimine. Butyronitrile is formed by butylimine dehydrogenation. The formation of butyronitrile from butylamine occurs via the stepwise dehydrogenation of the amine. The presence of ammonia in the gas phase suppresses the hydrogenolysis of either butylalcohol or butylamine. 11 refs., 8 figs., 2 tabs.
Extracting lexical knowledge from dictionary text

A lexicon providing subsystems, that produces text-specific lexicons from selected machine readable dictionary definitions from the Longman Dictionary of Contemporary English (LDOCE; Procter, 1978) has been developed. Although designed as part of a larger system for Preference Semantics (Wilks; 1972, 1975a, 1975b, 1978) and knowledge-based parsing, the resulting lexicons are in a very general predicate and frame representation that would have utility as part of a variety of differing systems of language analysis. The input to this subsystem is unconstrained text; the database is LDOCE (a machine-readable dictionary which is, itself, simply a special purpose text); the output is a collection of lexical semantic objects, one for every word sense, of every part of speech, of every word in the text. Each lexical semantic object in this lexicon contains grammatical and sub-categorization information, often with general (and sometimes specific) grammatical predictions; most of these objects also have semantic selection codes; and many have contextual (pragmatic, LDOCE subject code) knowledge as well.
Global constraints of Gauss' law and the solution to the strong CP problem

Abstract It is shown that the global constraints of Gauss' law ensure that the vacuum angle must be quantized in gauge theories in the presence of magnetic monopoles. Our quantization rule for the vacuum angle is derived as θ = 2 πN / n ( n ≠ 0) with integer n being the relevant topological charge [1] of the magnetic monopoles and N is an integer which is not fixed by this method. This provides interesting new understandings and ideas for the strong CP problem and its new solution with the magnetic monopoles as originally proposed recently by the author. Therefore, we conclude [1] again that the strong CP problem can be automatically solved in the presence of magnetic monopoles, the fact that the strong CP-violation can be only so small or vanishing may be a signal for the existence of magnetic monopoles, and the universe is open. If there exists actually the axion field a ( x ), the value of the physical axion field a phy ( x ) will not be quantized. However, the expectation value of the CP violating density ϵ μνγσ F μν a F γσ a will be quantized. For the special values of topological number n , it can be vanishing or very small even without using the Peccei-Quinn dynamical adjusting.
CHARACTERIZING THE CIRCUMGALACTIC MEDIUM OF NEARBY GALAXIES WITH HST/COS AND HST/STIS ABSORPTION-LINE SPECTROSCOPY*

The circumgalactic medium (CGM) of late-type galaxies is characterized using UV spectroscopy of 11 targeted QSO/galaxy pairs at z ≤ 0.02 with the Hubble Space Telescope Cosmic Origins Spectrograph (COS) and ~60 serendipitous absorber/galaxy pairs at z ≤ 0.2 with the Space Telescope Imaging Spectrograph. CGM warm cloud properties are derived, including volume filling factors of 3%-5%, cloud sizes of 0.1-30 kpc, masses of 10-108 M ☉, and metallicities of ~0.1-1 Z ☉. Almost all warm CGM clouds within 0.5 R vir are metal-bearing and many have velocities consistent with being bound, "galactic fountain" clouds. For galaxies with L 0.1 L*, the total mass in these warm CGM clouds approaches 1010 M ☉, ~10%-15% of the total baryons in massive spirals and comparable to the baryons in their parent galaxy disks. This leaves 50% of massive spiral-galaxy baryons "missing." Dwarfs (<0.1 L*) have smaller area covering factors and warm CGM masses (≤5% baryon fraction), suggesting that many of their warm clouds escape. Constant warm cloud internal pressures as a function of impact parameter (P/k ~ 10 cm–3 K) support the inference that previous COS detections of broad, shallow O VI and Lyα absorptions are of an extensive (~400-600 kpc), hot (T ≈ 106 K), intra-cloud gas which is very massive (≥1011 M ☉). While the warm CGM clouds cannot account for all the "missing baryons" in spirals, the hot intra-group gas can, and could account for ~20% of the cosmic baryon census at z ~ 0 if this hot gas is ubiquitous among spiral groups.
A new method for the generation and cyclization of iminyl radicals via the Hudson reaction.

A mild new synthetic procedure has been developed for in situ generation and cyclization of iminyl radicals onto pendant alkenes, followed by functionalization of the resulting carbon radical by one of a variety of trapping reagents. The key process in the method involves production of the iminyl radical via treatment of an aldoxime or ketoxime with readily available 2,6-dimethylbenzenesulfinyl chloride at −50 °C to room temperature (Hudson reaction).
The Two‐Mode Problem: Second‐Best Pricing and Capacity

Suppose that there are two congestible modes of travel from A to B — road and rail for concreteness — which are imperfect substitutes in demand. Road congestion from A to B is underpriced; this is an unalterable distortion. Compared to the first best, should the transportation planner choose a wider or narrower road, raise or lower the rail fare, and expand or contract rail capacity? This paper provides a synthetic review of the literature on the problem, presents some new results, and discusses directions for future research on this and related second-best problems.
Traffic Complexity Measurement Under Higher Levels of Automation and Higher Traffic Densities

An understanding of the complexity factors that affect controller workload under higher levels of automation for conflict detection and resolution and under higher traffic densities is critical for future operations. This paper examines traffic complexity variables under higher levels of automation where the human controller is still in the loop, but is being supported by advanced conflict detection and resolution automation. The study involved two conflict resolution automation modes (i.e., trial-planning automation and advisory automation) and three traffic densities (i.e., 1X, 2X and 3X). The results indicate that under the 1X traffic condition, controller workload was the lowest with advanced levels of automation. The complexity and workload increased progressively for the 2X and 3X traffic conditions. Results also showed that several variables such as horizontal proximity, aircraft density, separation criticality index, and two degrees of freedom indices appear to be relevant complexity measures for ...
Enhanced piezoelectric properties of lead zirconate titanate (PZT)sol-gel derived ceramics using single crystal PZT cubes

Piezoceramic materials have attracted much attention for sensing, actuation, structural health monitoring and energy harvesting applications in the past two decades due to their excellent coupling between energy in the mechanical and electrical domains. Among all piezoceramic materials, lead zirconate titanate (PZT) has been the most broadly studied and implemented, in industrial applications due to its high piezoelectric coupling coefficients. Piezoceramic materials are most often employed as thin films or monolithic wafers. While there are numerous methods for the synthesis of PZT films, the sol-gel processing technique is the most widely used due to its low densification temperature, the ease at which the film can be applied without costly physical deposition equipment and the capability to fabricate both thin and thick films. However, the piezoelectric properties of PZT sol-gel derived films are substantially lower than those of bulk materials, which limit the application of sol-gel films. In comparison, single crystal PZT materials have higher piezoelectric coupling coefficients than polycrystalline materials due to their uniform dipole alignment. This paper will introduce a novel technique to enhance the piezoelectric properties of PZT sol-gel derived ceramics through the use of single crystal PbZr 0.52 Ti 0.48 O 3 microcubes as an inclusion in the PZT sol-gel. The PZT single crystal cubes are synthesized through a hydrothermal based method and their geometry and crystal structure is characterized through scanning electron microscopy (SEM) and X-ray diffraction (XRD). A mixture of PZT cubes and sol-gel will then be sintered to crystallize the sol-gel and obtain full density of the ceramic. XRD and SEM analysis of the cross section of the final ceramics will be performed and compared to show the crystal structure and microstructure of the samples. The P-E properties of the samples will be tested using a Sawyer-Tower circuit. Finally, a laser interferometer will be used to directly measure the piezoelectric strain-coupling coefficient of the PZT sol-gel ceramics with and without PZT cube inclusions. The results will show that with the integration of PZ 0.52 T 0.48 crystal inclusions the d33 coupling coefficient will increase more than 200% compared to that of pure PbZr 0.52 Ti 0.48 O 3 sol-gel.
Comparing equivalent network services through dynamic processing time prediction

Computer networks provide the potential for resource sharing. Realization of this potential requires knowledge of the available resources within the network. Moreover, if a given resource is available at more than one host, selection of the most appropriate host is required. This paper develops a dynamic means for host selection assuming that the evaluation metric is processing time. An experiment is described which provides an initial evaluation of the key component of the methodology on two separate systems. The paper concludes with a discussion of some overall insights into the applicability of the methodology and its implementation requirements.
ANGULAR DISTRIBUTION OF NEUTRONS SCATTERED FROM CADMIUM, TIN, AND BISMUTH

The differential cross sections for the scattering of 3.7-Mev neutrons from cadmium, tin, and bismuth have been measured over an angular range between 13 degrees and 140 degrees with an angular resolution of about \ifmmode\pm\else\textpm\fi{}10 degrees. The effects due to higher-order scattering have been removed at each measured angle by extrapolation. Previous measurements of the differential cross sections of aluminum, iron, and lead gave a uniform shift of the position of the first minima in the curve with atomic weight. In the present measurements, the curves for cadmium and tin, while quite similar, do not fall uniformly between those of iron and lead. The curve for bismuth, however, is again quite similar to that for lead. Possible explanations of this behavior are discussed in light of the continuum theory of nuclear reactions.
A randomized trial of breakthrough pain during combined spinal-epidural versus epidural labor analgesia in parous women.

BACKGROUND There is controversy regarding the benefits and risks of combined spinal-epidural compared with epidural analgesia (CSE, EPID) for labor analgesia. We hypothesized that CSE would result in fewer patient requests for top-up doses compared to EPID. METHODS One-hundred ASA physical status I or II parous women at term in early labor (<5 cm cervical dilation) requesting analgesia were randomized in double-blind fashion to the EPID group (epidural bupivacaine 2.5 mg/mL, 3 mL, followed by bupivacaine 1.25 mg/mL, 10 mL with fentanyl 50 microg) or the CSE group (intrathecal bupivacaine 2.5 mg with fentanyl 25 microg). Both groups received identical infusions of bupivacaine 0.625 mg/mL with fentanyl 2 microg/mL at 12 mL/h. The primary outcome variable was the number of top-up doses requested to treat breakthrough pain. RESULTS There was no significant difference between the two groups in the percentage of patients requesting top-up doses (44% CSE vs 51% EPID; 95% confidence interval of the difference -28% to +14%) nor in the need for multiple top-up doses (14% CSE vs 15% EPID). Visual analog scale scores were lower in the CSE group compared to the EPID group at 10 min after initiation of analgesia [median 0 cm (0, 0) vs 4 cm (1, 6) respectively, P < 0.001] and at 30 min [0 cm (0, 0) vs 0 cm (0, 1), respectively, P = 0.03]. CONCLUSIONS We did not find a difference in the need for top-up doses in parous patients; however, CSE provided better analgesia in the first 30 min compared to EPID.
Study of Cullum's and Willoughby's Lanczos method for Wilson fermions

Abstract The Lanczos method of Cullum and Willoughby is studied for Euclidean Wilson fermions in quenched and unquenched SU(2) gauge fields on lattices of volume ranging from 4 4 to 16 4 . The method is reliable even on larger lattices, but its cost for the computation of a given fraction of the spectrum grows (approximately) with the square of the lattice volume. We investigate the convergence behaviour and show that it is closely linked with the local spectral density. Complete spectra are determined on lattices up to 8 3 · 12. For configurations where all eigenvalues are computed, we give numerical values for the fermionic determinants and results for spectral densities. Determinants are also given for staggered fermions whose quenched and unquenched spectra were studied in a previous publication.
Catalytic Decomposition of Diazo Compounds as a Method for Generating Carbonyl-Ylide Dipoles

The transition metal catalyzed reaction of α-diazo carbonyl compounds has found numerous applications in organic synthesis, and its use in either heterocyclic or carbocyclic ring formation is well-precedented. In contrast to other catalysts that are suitable for carbenoid reactions of diazo compounds, those constructed with the dirhodium(II) framework are most amenable to ligand modification that, in turn, can influence reaction selectivity. The reaction of rhodium carbenoids with carbonyl groups represents a very efficient method for generating carbonyl ylide dipoles. Rhodium-mediated carbenoid–carbonyl cyclization reactions have been extensively utilized as a powerful method for the construction of a variety of novel polycyclic ring systems. This article will emphasize some of the more recent synthetic applications of the tandem cyclization/cycloaddition cascade for natural product synthesis. Discussion centers on the chemical behavior of the rhodium metal–carbenoid complex that is often affected by the nature of the ligand groups attached to the metal center.
The Effects of Cued Interaction and Ability Grouping during Cooperative Computer-Based Science Instruction.

The purpose of this study was to investigate the effects of verbal interaction cues and ability grouping within a cooperative learning computer-based program. We blocked 231 eighth graders in a required science class by ability and randomly assigned them to homogeneous lower-ability, homogeneous higher-ability, or heterogeneous mixed-ability dyads. Each dyad was randomly assigned to a computer program that either did or did not contain verbal interaction cues designed to facilitate summarizing and explaining between partners. Results indicated that students using the cued version of the program performed significantly better on the posttest than students using the noncued version. Direct observation of student interaction indicated that students in cued dyads exhibited significantly more summarizing and helping behaviors than noncued students. Furthermore, higher-ability dyads exhibited significantly less off-task behavior than the other dyads. Implications for designing computer-based instruction for cooperative settings are provided.
Visual perception studies to improve the perceived sharpness of television images

Over the past century a number of factors have been observed to improve the quality of sampled images. Three of these phenomena are reviewed. The reasons for improvement based on perception studies are given, the improvements are quantified, and how they can be used in a practical television system is shown. Interlaced scanning reduces vertical resolution for several reasons involving spatial and temporal masking effects in visual perception. A progressive scan avoids these limitations. Because of the oblique effect in vision and the statistical orientation of lines in scenes, diagonal sampling reduces the required number of pixels in an image. Quantitatively, our measurements show that the number of pixels is reduced by a factor of 1.4 for the same perceived sharpness. In addition, by taking advantage of the octave-wide tuning bands in visual perception, our measurements show that the perceived resolution in the vertical direction for a progressive scan can be double that of an interlaced scan. Using diagonal sampling, a 1920×1080 image with progressive scan at 60 frames/s requires the same transmission bit rate as a 1920×1080 Cartesian sampled image scanned interlaced at 30 frames/s. This results in an image that appears to be much sharper than the 1080 line interlaced format without the interlace artifacts.
Institutions, Capital, and Growth

The international development community has encouraged investment in physical and human capital as a precursor to economic progress. Recent evidence shows, however, that increases in capital do not always lead to increases in output. We develop a growth model where the allocation and productivity of capital depends on a country's institutions. We find that increases in physical and human capital lead to output growth only in countries with good institutions. In countries with bad institutions, increases in capital lead to negative growth rates because additions to the capital stock tend to be employed in rent-seeking and other socially unproductive activities.
A highly selective synthesis of (Z)-α,β-unsaturated ketones

Abstract New Wadsworth-Emmons reagents, bis(2,2,2-trifluoroethyl)-(2-oxopropyl)phosphonate 6 and bis(2,2,2-trifluoroethyl)-(1-methyl-2-oxopropyl)-phosphonate 7 were prepared and their reactions with aldehydes yielded disubstituted and trisubstituted (Z)-α,β-unsaturated ketones.
Tax distortions, household production, and black-market work

Abstract This paper studies an economy with high- and low-productivity households. Household services are produced either by households themselves or are purchased in a white or black market. Black market work is inefficient (efficient) when it otherwise would have been done in the white market (within the household). With low (high) tax wedges, the black market reduces (increases) welfare by competing with white-market production (own-household production). With intermediate tax wedges, the welfare effect of a black market is ambiguous: welfare is improved (reduced) when black services are demanded by low- (high-) productivity households. An increase in the tax wedge may then reduce the benefits from a black service market.
The spin temperature of warm interstellar H I

Collisional excitation of the 21 cm hyperne transition is not strong enough to thermalize it in warm neutral (\intercloud") interstellar gas, which we show by simultaneously solving the equations of ionization and collisional equilibrium under typical conditions. Coupling of the 21 cm excitation temperature and local gas motions may be established by the Ly- radiation eld, but only if strong Galactic Ly- radiation permeates the gas in question. The Ly- radiation tends to impart to the gas its own characteristic temperature, which is determined by the range of gas motions that occur on the spatial scale of the Ly- scattering. In general, the calculation of H I spin temperatures is a more dicult and interesting problem than might have been expected, as is any interpretation of H I spin temperature measurements.
Microporous and dense inorganic membranes: Current status and prospective

The paper attempts to summarize recent significant progress in synthesis of microporous and dense inorganic membranes with the help of the results obtained in the author's laboratory or reported in the literature. The paper first reviews several methods for synthesis of microporous amorphous and polycrystalline (zeolite) inorganic membranes and their major characteristics. These microporous membranes exhibit fascinating gas permeation and separation properties. The paper also reviews equally impressive progress on oxygen semipermeable dense oxygen ionic-conducting ceramic membranes and hydrogen semipermeable metal membranes. Searching for better membrane materials, developing effective membrane synthesis methods, and improving chemical and structural stability of the current membrane materials will continue to be the focus of active research in these areas. Specific examples of the future research include synthesis of micro and mesoporous polycrystalline inorganic membranes with oriented pores and development of more effective dense proton-conducting ceramic membranes for high temperature hydrogen separation and membrane reactor applications.
Synthesis of (+)-Casuarine

The first synthesis of (+)-casuarine ((+)-6), a pentahydroxy pyrrolizidine alkaloid of the alexine/australine subclass, is described. The key step is a tandem [4 + 2]/[3 + 2] nitroalkene cycloaddition involving nitrobenzoate 13, chiral vinyl ether 16c, and vinyl silane 10, which establishes five of the six stereocenters present in this potent glycosidase inhibitor. The completion of the synthesis requires only four additional steps to deliver the final product in 20% overall yield.
Phenomenal data-mining

Phenomenal data mining finds relations between the data and the phenomena that give rise to data rather than just relations among the data..Science and common sense both tell us that the facts about the world are not directly observable but can be inferred from observations about the effects of actions. What people infer about the world is not just relations among observations but relations among entities that are much more stable than observations. For example, 3-dimensional objects are more stable than the image on a person's retina, the information directly obtained from feeling an object or on an image scanned into a computer..This talk concerns what can be inferred by programs about phenomena from data and what facts are relevant to doing this. In order to infer phenomena from data, facts about their relations must be supplied. Sometimes these facts can be implicit in the programs that look for the phenomena, but more generality is achieved if the facts are represented as sentences of logic in a knowledge base used by the programs..Creating knowledge bases containing both common sense knowledge and knowledge of the domain of the data will be a lot of work. This is unavoidable..The result of phenomenal data-mining can include an extended database with additional fields on existing relations and new relations. Thus the relations describing supermarket baskets can be extended with a customer field, and new relations about customers and their properties can be introduced..
Perverse sheaves on affine flags and nilpotent cone of the langlands dual group

This paper is a continuation of [2]. In [2], we constructed an equivalence between the derived category of equivariant coherent sheaves on the cotangent bundle to the flag variety of a simple algebraic group and a (quotient of) a category of constructible sheaves on the affine flag variety of the Langlands dual group. Below we prove certain properties of this equivalence related to cells in the affineWeyl group; provide a similar “Langlands dual” description for the category of equivariant coherent sheaves on the nilpotent cone, and link it to perverse coherent sheaves; and deduce some conjectures by Lusztig and Ostrik.
Community Foundations, Organizational Strategy, and Public Policy:

This empirical study of the strategic direction of California community foundations explores how this choice is affected by organizational and community characteristics and by external forces. The ...
Ion-induced grain growth in multilayer and coevaporated metal alloy thin films

Abstract Irradiation experiments were conducted on multilayer (ML) and coevaporated (CO) thin films in order to examine the role that the heat-of-mixing (ΔHmix) has in ion-induced grain growth. Room-temperature irradiations using 1.7 MeV Xe were performed in the High Voltage Electron Microscope at Argonne National Laboratory. The alloys studied (Pt-Ti, Pt-V, Pt-Ni, Au-Co and Ni-Al) spanned a large range of ΔHmix values. Comparison of grain growth rates between ML and CO films of a given alloy confirmed a heat of mixing effect. Differences in grain growth rates between ML and CO films scaled according to the sign and magnitude of ΔHmix of the system (with the exception of the Pt-V system). Substantial variations in growth rates among CO alloy films experiencing similar irradiation damage demonstrated that a purely collisional approach is inadequate for describing ion-induced grain growth and consideration must also be given to material-specific properties. Results from CO alloy films were consistent with a thermal spike model of ion-induced grain growth. The grain boundary mobility was observed to be proportional to the thermal spike-related parameter, F 2 D ΔH 3 coh , where FD is the energy deposited in nuclear interactions and ΔHcoh is the cohesive energy.
Bits, matrices and 1/N

We propose a simple string bit formalism for interacting strings in a plane wave background, in terms of supersymmetric quantum mechanics with a symmetric product target-space. We construct the light-cone supersymmetry generators and hamiltonian at finite string coupling. We find a precise match between string amplitudes and the non-planar corrections to the correlation functions of BMN operators computed from gauge theory, and conjecture that this correspondence extends to all orders in perturbation theory. We also give a simple RG explanation for why the effective string coupling is g2 = J2/N instead of gs = gym2.
Correlation between Ventromedial Prefrontal Cortex Activation to Food Aromas and Cue-driven Eating: An fMRI Study.

Food aromas are signals associated with both food's availability and pleasure. Previous research from this laboratory has shown that food aromas under fasting conditions evoke robust activation of medial prefrontal brain regions thought to reflect reward value (Bragulat et al., Obesity (Silver Spring), 18(8): 1566–1571, 2010). In the current study, 18 women (11 normal weight and 7 obese) underwent a 2-day imaging study (one after being fed and one while fasting). All were imaged on a 3T Siemens Trio-Tim scanner while sniffing two food (F; pasta and beef) odors, one non-food (NF; Douglas fir) odor, and an odorless control (CO). Prior to imaging, participants rated hunger and perceived odor qualities and completed the Dutch Eating Behavior Questionnaire (DEBQ) to assess "externality" (the extent to which eating is driven by external food cues). Across all participants, both food and non-food odors (compared to CO) elicited large blood oxygenation level dependent (BOLD) responses in olfactory and reward-related areas, including the medial prefrontal and anterior cingulate cortex, bilateral orbitofrontal cortex, and bilateral piriform cortex, amygdala, and hippocampus. However, food odors produced greater activation of medial prefrontal cortex, left lateral orbitofrontal cortex, and inferior insula than non-food odors. Moreover, there was a significant correlation between the (F > CO) BOLD response in ventromedial prefrontal cortex and “externality” sub-scale scores of the DEBQ, but only under the fed condition; no such correlation was present with the (NF > CO) response. This suggests that in those with high externality, ventromedial prefrontal cortex may inappropriately valuate external food cues in the absence of internal hunger.
COMPREHENSIVE SPECTROSCOPIC DATA TABULATIONS AND PROGRESS IN THE COMPILATION OF ATOMIC TRANSITION PROBABILITIES

The critical data compilation work as well as the bibliographical efforts of two data centers on atomic spectroscopy at the National Institute of Standards and Technology (formerly the National Bureau of Standards) are briefly reviewed. A complete listing of all current compilations on wavelengths, energy levels and transition probabilities is given. A recently completed large tabulation of atomic transition probabilities for the Fe-group elements comprising about 18000 lines is discussed in some detail, and several data comparisons are presented in order to provide an impression of the current status of these atomic data.
Patient-controlled analgesia in adolescents

Patient-controlled analgesia (PCA) is a method of administering narcotics in which the patient activates a machine to administer a small bolus of narcotic. In the first year of PCA use in our hospital, 26 patients used PCA. We suggest a dose volume of 0.015 mg/kg/dose and a 4-hour limit of 0.25 mg/kg/4 hr, with a lock-out of 10 minutes. Patients used approximately equivalent amounts to standard parenteral narcotics, but there was a wide interpatient variability in the amount of narcotic used. No clinical respiratory depression was noted, and patients did not titrate themselves to complete analgesia. PCA is an effective means of pain control in adolescent patients.
Structure and mechanism of the pepsin-like family of aspartic peptidases.

-AmyloidPrecursor Protein4434D. Napsins (Novel Aspartic Peptidases) 4435E. Cathepsin E 4435F. Plant Aspartic Peptidases 44351. Plant Specific Inserts 4436III. Structural Aspects of Aspartic Peptidases 4436IV. The Amino Terminal Prosegment Region ofAspartic Peptidases4442V. Active Site Engineering 4444A. P1 Specificity 4444B. The Flap 4444C. Active Site Mutations to Address SpecificityQuestions in Other Positions4444VI. Substrate Design and Its Impact on InhibitorDesign4447VII. Inhibitors of Aspartic Peptidases 4448A. Synthetic Inhibitors 4448B. Naturally-Occurring Protein and PeptideInhibitors4450VIII. Mechanistic Studies 4452IX. Summary 4455X. Acknowledgments 4455XI. References 4455
The origin of water soluble particulate iron in the Asian atmospheric outflow

[1] Iron, and in particular water soluble iron, is an important trace nutrient in the surface ocean, and therefore an important component in the global carbon cycle. Deposition of Asian aerosol is thought to be a primary source of water soluble iron in the northern Pacific. Analysis of aerosol samples obtained during the Aerosol Characterization Experiment (ACE)–Asia field campaign from Jeju Island, Korea, which intercepts the outflow from the Asian continent, shows that water soluble iron is not dominated by mineral dust sources even during large dust storms. Instead, our analysis indicates that particulate soluble iron and elemental carbon concentrations are correlated. This leads to the conclusion that soluble iron in this region is strongly connected to anthropogenic activity and not connected to mineral dust emissions, especially if the budget averaged over annual time scales is considered.
The semiconductor industry's nanoelectronics research initiative: motivation and challenges

In this presentation, the scaling challenges facing current Complimentary Metal Oxide Semiconductor (CMOS) technology will be discussed, along with the ultimate limits for charge-switching based devices. From this motivation, the current status of the Nanoelectronics Research Initiative (NRI) will be discussed, with an overview of the current research topics being investigated at the NRI centers.
Metallophthalocyanine-catalyzed cyclopropanation

Abstract Metallophthalocyanine-catalyzed carbenoid reactions have had little attention to date. Recently these metal complexes have been found to catalyze cyclopropanation reactions. We have investigated these metallophthalocyanines in reactions to catalyze cyclopropanation from donor–acceptor carbenoids. The yields and diastereoselectivity of these reactions are influenced by the nature of the styrene as well as the aryldiazoacetate and catalyst. The products have been synthesized in short reaction times (1 h), with good yields (up to 84%), and high diastereoselectivity (up to 20:1 ratio cis / trans products).
Parafrase-2: an environment for parallelizing, partitioning, synchronizing, and scheduling programs on multiprocessors

Parafrase-2 is a vectorizing/parallelizing compiler implemented as a source to source code restructurer. This paper discusses the organization of Parafrase-2 and goals of the project. Specific topics discussed are : dependence analysis, timing and overhead analysis, interprocedural analysis, automatic scheduling and the graphical user interface.
Multiple roles for the Na,K-ATPase subunits, Atp1a1 and Fxyd1, during brain ventricle development.

Formation of the vertebrate brain ventricles requires both production of cerebrospinal fluid (CSF), and its retention in the ventricles. The Na,K-ATPase is required for brain ventricle development, and we show here that this protein complex impacts three associated processes. The first requires both the alpha subunit (Atp1a1) and the regulatory subunit, Fxyd1, and leads to formation of a cohesive neuroepithelium, with continuous apical junctions. The second process leads to modulation of neuroepithelial permeability, and requires Atp1a1, which increases permeability with partial loss of function and decreases it with overexpression. In contrast, fxyd1 overexpression does not alter neuroepithelial permeability, suggesting that its activity is limited to neuroepithelium formation. RhoA regulates both neuroepithelium formation and permeability, downstream of the Na,K-ATPase. A third process, likely to be CSF production, is RhoA-independent, requiring Atp1a1, but not Fxyd1. Consistent with a role for Na,K-ATPase pump function, the inhibitor ouabain prevents neuroepithelium formation, while intracellular Na þ increases after Atp1a1 and Fxyd1 loss of function. These data include the first reported role for Fxyd1 in the developing brain, and indicate that the Na,K-ATPase regulates three aspects of brain ventricle development essential for normal function: formation of a cohesive neuroepithelium, restriction of neuroepithelial permeability, and production of CSF.
On zeros of Eisenstein series for genus zero Fuchsian groups

Let r < SL 2 (R) be a genus zero Fuchsian group of the first kind with ∞ as a cusp, and let E Γ 2k be the holomorphic Eisenstein series of weight 2k on r that is nonvanishing at ∞ and vanishes at all the other cusps (provided that such an Eisenstein series exists). Under certain assumptions on Γ, and on a choice of a fundamental domain F, we prove that all but possibly c(Γ, F) of the nontrivial zeros of E Γ 2k lie on a certain subset of {z ∈ h: j Γ (z) ∈ R}. Here c(Γ, F) is a constant that does not depend on the weight, S) is the upper half-plane, and j Γ is the canonical hauptmodul for Γ.
Cycloisomerization of Enynes via Rhodium Vinylidene-Mediated Catalysis

A novel rhodium-catalyzed cycloisomerization has been developed which converts various acyclic enynes to their cyclic diene isomers with endoselectivity. Both [RhCl(COD)]2/P(4-FC6H4)3 and RhCl(PPh3)3 catalyst systems are effective in promoting the C−C bond-forming cyclization of enynes to furnish carbo- and heterocycles in good to excellent yield. Deuterium labeling studies suggest that the reaction proceeds through the formation of a rhodium vinylidene followed by subsequent [2 + 2] cycloaddition with the alkene and ring-opening of the resulting rhodacyclobutane. These mechanistic studies reevaluate a previously proposed reaction pathway and lead to the discovery of a new cycloisomerization reaction that involves migration of silyl and selenyl substituents at the alkyne of enyne substrates upon cyclization.
On Bounding the Betti Numbers and Computing the Euler Characteristic of Semi-Algebraic Sets

In this paper we prove new bounds on the sum of the Betti numbers of closed semi-algebraic sets and also give the first single exponential time algorithm for computing the Euler characteristic of arbitrary closed semi-algebraic sets. Given a closed semi-algebraic set S $\subset$ R k defined as the intersection of a real variety, Q=0, deg(Q)≤d, whose real dimension is k', with a set defined by a quantifier-free Boolean formula with no negations with atoms of the form P i =0, P i ≥ 0, P i ≤ 0, deg(P i ) ≤ d, 1≤ i≤ s, we prove that the sum of the Betti numbers of S is bounded by s k' (O(d)) k . This result generalizes the Oleinik—Petrovsky—Thom—Milnor bound in two directions. Firstly, our bound applies to arbitrary unions of basic closed semi-algebraic sets, not just for basic semi-algebraic sets. Secondly, the combinatorial part (the part depending on s ) in our bound, depends on the dimension of the variety rather than that of the ambient space. It also generalizes the result in [4] where a similar bound is proven for the number of connected components. We also prove that the sum of the Betti numbers of S is bounded by s k' 2 O(k2 m4) in case the total number of monomials occurring in the polynomials in $ {\cal P} \cup \{Q\}$ is m. Using the tools developed for the above results, as well as some additional techniques, we give the first single exponential time algorithm for computing the Euler characteristic of arbitrary closed semi-algebraic sets.
Synthesis and structure of [1-5-η-6-exo-Re(CO)5C7H8]Mn(CO)3. The first example of metal carbonyl anion addition to a coordinated cyclic π-hydrocarbon

Abstract The metal carbonyl anion Re(CO) 5 − adds to the cycloheptatriene ligand in [(η-C 7 H 8 )Mn(CO) 3 ]BF 4 to give the title cycloheptadienyl complex, whose X-ray-determined structure shows the Re(CO) 5 moiety to be in an exo position. Although previous attempts to add metal carbonyl anions to cyclic π-hydrocarbons were unsuccessful, the present report clearly demonstrates that such reactions are possible.
A robustified hidden markov model for visual tracking with subspace representation

This paper describes a new, robustified Hidden Markov Model for target tracking using a subspace representation. The Hidden Markov Model (HMM) provides a powerful framework for the probabilistic modelling of observations and states. Visual tracking problems are often cast as an inference problem within the HMM framework. Probabilistic Principal Component Analysis (PPCA), a classic subspace representation method, is a popular tool for appearance modelling because it provides a compact representation for high-dimensional data. Previous subspace based tracking algorithms assume the image observations were generated from a Gaussian distribution parameterized by principal components. One drawback of using Gaussian density model is that atypical observations cannot be modelled well. Hence, they are very sensitive to outliers. To address this problem, we propose to augment the HMM by adding a set of latent variables { w i } t i =1 to adjust the shape of the observation distribution. By carefully choosing the distribution of { w i } t i =1, we obtain a more robust observation distribution with heavier tails than a Gaussian. Numerical experiments demonstrate the effectiveness of this new framework in cases where the target objects are corrupted by noise or occlusion.
Floquet theory for integral and integro-differential equations

We study the extension of Hill's method of infinite determinants to the case of integro-differential equations with periodic coefficients and kernels. We develop the analytical theory of such methods, and we obtain certain qualitative properties of the equations that determine the boundaries between regions of dynamic stability and dynamic instability.
Algorithms for interval structures with applications

We present new algorithms for two problems on interval structures that arise in computer-aided manufacturing and in other areas. We give an O(Kn) time algorithm for the single-source K-link shortest path problem on an interval graph with n weighted vertices, and two O(n) time algorithms for a generalized version of the optimal color-spanning problem for n points on a real line, where each point is assigned one of m colors ([email protected]?n). A standard approach for solving the K-link shortest path problem would take O(Kn^2) time, and thus our result offers a linear time improvement. The previously best known algorithm for the optimal color-spanning problem in R^1 takes O(n) time and space. We provide two algorithms for a generalized version of this problem in which each color must appear a specified minimum number of times. One of these two solutions is suitable for an online processing of the (streaming) input points; it uses O(m) working space for the ordinary one-dimensional optimal color-spanning problem. We also show several applications of our algorithms in computer-aided manufacturing and in other areas.
Seismic response simulations of bridges considering shear-flexural interaction of columns

Bridge columns are subjected to combined actions of axial force, shear force and bending moment during earthquakes, caused by spatially-complex earthquake motions, features of structural configurations and the interaction between input and response characteristics. Combined actions can have significant effects on the force and deformation capacity of RC columns, resulting in unexpected large deformations and extensive damage that in turn influences the performance of bridges as vital components of transportation systems. This paper evaluates the seismic response of three prototype reinforced concrete bridges using comprehensive numerical models that are capable of simulating the complex soil-structural interaction effects and nonlinear behavior of columns. An analytical approach that can capture the shearflexural interacting behavior is developed to model the realistic nonlinear behavior of RC columns, including the pinching behavior, strength deterioration and stiffness softening due to combined actions of shear force, axial force and bending moment. Seismic response analyses were conducted on the prototype bridges under suites of ground motions. Response quantities of bridges (e.g., drift, acceleration, section force and section moment etc.) are compared and evaluated to identify the effects of vertical motion, structural characteristics and the shear-flexural interaction on seismic demand of bridges.