cssi/SciSciGPT-SciSciNet huggingface dataset:
Workforce development for comparative effectiveness research: training programs funded by the American Recovery and Reinvestment Act.

Aim: We conducted a midstream assessment of the comparative effectiveness research (CER) training programs funded by the American Recovery and Reinvestment Act (ARRA) by examining program characteristics, planned curriculum development activities and core competencies. Materials & methods: We examined all 43 training projects funded by the US$46 million ARRA CER investment, collecting data from key informant discussions and a technical expert panel. Results: The majority of projects leveraged institutional resources to provide an individualized combination of didactic and experiential learning supported by strong mentorship. Core competencies included skills in statistical modeling, evidence synthesis (systematic reviews and meta-analysis) and general research design skills. Conclusion: ARRA-supported CER training programs enhanced workforce capacity by developing curricula and preparing CER researchers to apply emerging methods and utilize new CER infrastructure.
Measurement of Asymmetric Optical Pumping of Ions Accelerating in a Magnetic-Field Gradient

We report observations of asymmetric optical pumping of argon ions accelerating in a magnetic-field gradient. The signature is a difference in the laser-induced-fluorescence emission amplitude from a pair of Zeeman-split states. A model that reproduces the dependence of the asymmetry on magnetic-field and ion-velocity gradients is described. With the model, the fluorescence intensity ratio provides a new method of measuring ion collisionality. This phenomenon has implications for interpreting stellar plasma spectroscopy data which often exhibit unequal Zeeman state intensities.
Robust controller design for a variable displacement hydraulic motor

Presents the robust control of a variable displacement hydraulic motor (VDHM). A feedback control structure consisting of two nested loops is employed. The inner feedback loop controls the position of the rocker arm which actuates the wobbler plate of the motor. The outer feedback loop regulates the motor shaft velocity such that shaft speed is guaranteed at steady state despite external torque loads. The control loops are closed in succession closing the inner loop first. For each loop design, step response data is collected from a VDHM laboratory test stand to generate analytical systems level models. Based on these models, feedback controllers are designed using classical loop shaping techniques. Feedback control, as opposed to feedforward control, maintains motor shaft velocity under nonpredictive torque loading conditions. In addition, the feedback structure eliminates the need for extensive system calibration when considering system parameter changes that result from component aging.
Magnetic Field Overlying Solar Eruption Regions and Kink and Torus Instabilities

Using a potential field source surface (PFSS) model, we study a magnetic field overlying erupted filaments in solar active regions. The filaments studied here were reported to experience a kink instability or a torus instability. The torus instability leads to a full eruption, while the kink instability leads to a full eruption or a failed eruption. It is found that for a full eruption, the field decreases with height more quickly than that for a failed eruption. A dividing line between a full eruption and a failed eruption is also found to be likely connected with the decay index n of the horizontal potential field due to sources external to the filament [n = − dlog (Bex)/dlog (h) , where h is height]: the decay index of a failed eruption tends to be smaller than that of a full eruption. The difference of the decay indexes between a full eruption and a failed eruption is statistically significant. These are supportive of previous theoretical and numerical simulation results. Another significant difference is the field strength at low altitude: for a failed eruption, the field strength is about a factor of 3 stronger than that for a full eruption. This suggests that the field strength at low altitude may be another factor in deciding whether or not a full eruption can take place. On the other hand, the decay index for the torus instability full eruption events exhibits no trend to exceed the decay index for the kink instability full eruption events on average, different from a suggestion derived from some MHD simulations. We discuss possible reasons that may cause this discrepancy.
Studies of higher twist and higher order effects in NLO and NNLO QCD analysis of lepton-nucleon scattering data on \(F_2\) and \(R ={\sigma_L}/{\sigma_T}\)

We report on the extraction of the higher twist contributions to $F_2$ and $R ={\sigma_L}/{\sigma_T}$ from global NLO and NNLO QCD fits to lepton nucleon scattering data over a wide range of $Q^2$ . The NLO fits require both target mass and higher twist contributions at low $Q^2$ . However, in the NNLO analysis, the data are described by the NNLO QCD predictions (with target mass corrections) without the need for any significant contributions from higher twist effects. An estimate of the difference between NLO and NNLO parton distribution functions is obtained.
Generators of Nonassociative Simple Moufang Loops over Finite Prime Fields

Abstract We present an elementary proof that the nonassociative simple Moufang loops over finite prime fields are generated by three elements. In the last section, we conclude that integral Cayley numbers of unit norm are generated multiplicatively by three elements.
The synthesis and study of new selenium and tellurium heterocyclic π-donors

Abstract Since the first reported synthesis of a tetratellurafulvalene π-donor [1], the number of compounds of this kind has slowly increased. We wish to report here the synthesis of two new tetratellurafulvalenes, tetramethylhexamethylene-tetratellurafulvalene (TMHM-TTeF) and dicyclopropylhexamethylenetetratellurafulvalene (CpHM-TTeF), together with their cyclic voltametry data and the conductivities of a number of their charge-transfer salts.
NEAR-INFRARED INTERFEROMETRIC, SPECTROSCOPIC, AND PHOTOMETRIC MONITORING OF T TAURI INNER DISKS

We present high angular resolution observations with the Keck Interferometer, high-dispersion spectroscopic observations with Keck/NIRSPEC, and near-IR photometric observations from PAIRITEL of a sample of 11 solar-type T Tauri stars in nine systems. We use these observations to probe the circumstellar material within 1 AU of these young stars, measuring the circumstellar-to-stellar flux ratios and angular size scales of the 2.2 μm emission. Our sample spans a range of stellar luminosities and mass accretion rates, allowing investigation of potential correlations between inner disk properties and stellar or accretion properties. We suggest that the mechanism by which the dusty inner disk is truncated may depend on the accretion rate of the source; in objects with low accretion rates, the stellar magnetospheres may truncate the disks, while sublimation may truncate dusty disks around sources with higher accretion rates. We have also included in our sample objects that are known to be highly variable (based on previous photometric and spectroscopic observations), and for several sources, we obtained multiple epochs of spectroscopic and interferometric data, supplemented by near-IR photometric monitoring, to search for inner disk variability. While time-variable veilings and accretion rates are observed in some sources, no strong evidence for inner disk pulsation is found.
A hyperconcentrator switch for routing bit-serial messages

Abstract In highly parallel message routing networks, it is sometimes desirable to concentrate relatively few messages on many wires onto fewer wires. We have designed a VLSI chip which is capable of concentrating bit-serial messages quickly for this purpose. This hyperconcentrator switch has a regular layout using ratioed nMOS and takes advantage of the relatively fast performance of large fan-in NOR gates in this technology. A signal incurs exactly 2 lg n gate delays through the switch, where n is the number of inputs to the circuit. The architecture generalizes to domino CMOS and BiCMOS as well. The hyperconcentrator design has applications other than message concentration. It can be used in a superconcentrator switch to provide fault tolerance when interconnections are nonfunctional. Multiple hyperconcentrator switches can be configured into a large partial concentrator switch. The hyperconcentrator design can also be used in a processor datapath to allow various manipulations on bits, including barrel shifting, APL-style compression and expansion, and bit interleaving.
5-Bromo-2-pyrone: An easily prepared ambiphilic diene and a synthetic equivalent of 2-pyrone in mild, thermal, Diels-Alder cycloadditions

Abstract 5-Bromo-2-pyrone, a solid prepared easily in one-flask according to a new route (eq. 1), has been found to undergo smooth and highly regiocontrolled 2+4-cycloadditions between 25–100°C with both electron-poor and electron-rich dienophiles; subsequent radical debrominations produced halogen-free bicyclic lactones, including a precursor to a vitamin D steroid, thus showing 5-bromo-2-pyrone to be a practical and effective synthetic equivalent of 2-pyrone in thermal Diels-Alder cycloaddition.
Galactic Motions in a Large-Scale Magnetic Field

RECENT observations on spiral galaxies have shown that their interstellar material cannot be in purely rotational motion. The evidence points to a circulation of interstellar gas between the galactic plane and the galactic halo.
Conventional and Unconventional Approaches to Exchange Rate Modeling and Assessment

We examine the relative predictive power of the sticky price monetary model, uncovered interest parity, and a transformation of net exports and net foreign assets. In addition to bringing Gourinchas and Rey's new approach and more recent data to bear, we implement the Clark–West procedure for testing the significance of out-of-sample forecasts. The interest rate parity relation holds better at long horizons and the net exports variable does well in predicting exchange rates at short horizons in sample. In out-of-sample forecasts, we find evidence that our proxy for Gourinchas and Rey's measure of external imbalances outperforms a random walk at short horizons as do some of the other models, although no single model uniformly beats the random walk forecast. Copyright © 2007 John Wiley & Sons, Ltd.
Hadrons as signature of black hole production at the LHC

Abstract In models with several large extra dimensions and fundamental Planck scale of the order of 1 TeV, black holes can be produced in large numbers at LHC energies. We compute the charged hadron spectra obtained from the decay of black holes created in pp and Pb+Pb collisions at LHC. We show that hadrons from black hole decay dominate at transverse momenta pT≳30–100 GeV/c compared to usual QCD processes and black hole production signals are easy to identify in hadron transverse momentum spectra. Furthermore we show that a measurement of the charged hadron spectra probes Planck scales up to 5 TeV for any number of extra dimensions.
Asymmetric synthesis of a taxol C-ring by aldol condensation and radical cyclization

Abstract In the context of a convergent approach to taxol, the asymmetric synthesis of a fully functionalized C-ring is described. Two asymmetric aldol reactions (Evans) are used to create the C5 and C7 stereocenters and the diastereoselective alkylation of a stereochemically and conformationally biased dioxanone to introduce, with the correct relative and absolute stereochemistry, the quaternary center at C8. Vinyl radical cyclization is used to close the C2,3 bond in good yield. This diastereoselective radical cyclization likely proceeds through a chair-like transition state with the maximum number of substituents equatorially disposed.
A 30-cm diameter argon ion source

A 30 cm diameter argon ion source was evaluated. Ion source beam currents up to 4a were extracted with ion energies ranging from 0.2 to 1.5 KeV. An ion optics scaling relation was developed for predicting ion beam extraction capability as a function of total extraction voltage, gas type, and screen grid open area. Ignition and emission characteristics of several hollow cathode geometries were assessed for purposes of defining discharge chamber and neutralizer cathodes. Also presented are ion beam profile characteristics which exhibit broad beam capability well suited for ion beam sputtering applications.
Anti-Self-Dual Instantons with Lagrangian Boundary Conditions I: Elliptic Theory

We study nonlocal Lagrangian boundary conditions for anti-self-dual instantons on 4-manifolds with a space-time splitting of the boundary. We establish the basic regularity and compactness properties (assuming L p -bounds on the curvature for p>2) as well as the Fredholm theory in a compact model case. The motivation for studying this boundary value problem lies in the construction of an instanton Floer homology for 3-manifolds with boundary. The present paper is part of a program proposed by Salamon for the proof of the Atiyah-Floer conjecture for homology-3-spheres.
Extrapolation of neutron-rich isotope cross-sections from projectile fragmentation

Using the measured fragmentation cross-sections produced from the 48 Ca and 64 Ni beams at 140 MeV per nucleon on 9 Be and 181 Ta targets, we find that the cross-sections of unmeasured neutron-rich nuclei can be extrapolated using a systematic trend involving the average binding energy. The extrapolated cross-sections will be very useful in planning experiments with neutron-rich isotopes produced from projectile fragmentation. The proposed method is general and could be applied to other fragmentation systems including those used in other radioactive ion beam facilities. Copyright c EPLA, 2007
Total synthesis of (±)-11-O-methyl-caesalpin J and its C-13 epimer

Abstract The biomimetic total syntheses of racemic 11- O -methyl-caesalpin J ( 9 ) and 13-epi-11- O -methyl-caesalpin J ( 10 ), via phenolic oxidative coupling of the accordingly substituted homoisoflavans 6 and 7 , are described.
High-temperature modification of Y5Sb3 and its ternary analogue Y5NixSb3-x

Abstract The high-temperature modification of Y 5 Sb 3 has been discovered: the Yb 5 Sb 3 structure type, Pnma space group, a =11.867(1), b =9.2247(9) and c =8.0977(8) A. It has been estimated that the first-order structural transition from the low-temperature form (Mn 5 Si 3 type) to the high-temperature form is above 1265°C but below 1400°C. Antimony atoms on one of the two sites can be partially substituted by Ni atoms, which results in a Y 5 Ni x Sb 3− x formula with 0≤ x 5 Ni 0.38 Sb 2.62 crystal, obtained by annealing a sample in an induction furnace for 2 h at 1265°C. All high-temperature nickel-containing phases Y 5 Ni x Sb 3− x with the ordered Yb 5 Sb 3 structure undergo a decomposition to low-temperature Y 5 Sb 3 (Mn 5 Si 3 type) and a nickel-containing phase, when annealed at 800°C. Extended Huckel tight-binding calculations show that substitution of Sb by Ni is unfavorable with respect to the Y–Sb bonding. The structure of Y 5 Ni x Sb 3− x is stabilized by the configurational entropy, resulting from a statistical mixture of Sb and Ni atoms on one site. Choice of an Sb site to be occupied by Ni is dictated by bonding maximization in the substituted structure. The high-temperature Y 5 Sb 3 and Y 5 Ni 0.38 Sb 2.62 phases are weak Pauli paramagnets.
Evaluation of the mathematical and economic basis for conversion processes in the LEAP energy-economy model

Abstract An evaluation was made of the mathematical and economic basis for conversion processes in the LEAP energy-economy model. Conversion processes are the main modelling subunit in LEAP used to represent energy conversion industries and are supposedly based on the classical economic theory of the firm. The study arose out of questions about the uniqueness and existence of LEAP solutions and their relation to classical equilibrium economic theory. An analysis of classical theory and LEAP model equations was made to determine their exact relationship. The conclusions drawn from this analysis were that LEAP theory is not consistent with the classical theory of the firm. Specifically, the capacity for factor formalism used by LEAP does not support a classical interpretation in terms of a technological production function for energy conversion processes. The economic implications of this inconsistency are suboptimal process operation and short term negative profits in years where plant operation should be terminated. A new capacity factor formalism, which retains the behavioural features of the original model, is proposed to resolve these discrepancies.
The Molecular Hydrogen Deficit in Gamma-Ray Burst Afterglows

Recent analysis of five gamma-ray burst (GRB) afterglow spectra reveals the absence of molecular hydrogen absorption lines, a surprising result in light of their large neutral hydrogen column densities and the detection of H2 in similar, more local star-forming regions such as 30 Doradus in the Large Magellanic Cloud (LMC). Observational evidence further indicates that the bulk of the neutral hydrogen column in these sight lines lies more than 100 pc from the GRB progenitor and that H2 was likely absent prior to the burst, suggesting that direct flux from the star, FUV background fields, or both suppressed its formation. We present one-dimensional radiation hydrodynamical models of GRB host galaxy environments, including self-consistent radiative transfer of both ionizing and Lyman-Werner (L-W) photons, nine-species primordial chemistry with dust formation of H2, and dust extinction of UV photons. We find that a single GRB progenitor is sufficient to ionize neutral hydrogen to distances of 50-100 pc, but that a galactic L-W background is required to dissociate molecular hydrogen in the ambient ISM. Intensities of 0.1-100 times the Galactic mean are necessary to destroy H2 in the cloud, depending on its density and metallicity. The minimum radii at which neutral hydrogen will be found in afterglow spectra is insensitive to the mass of the progenitor or the initial mass function (IMF) of its cluster, if present.
Chemically modified electrodes for electrocatalysis

At a modified electrode, electrocatalysis is accomplished by an immobilized redox substance acting as an electron transfer mediator between the electrode and a reaction substrate. Such mediated electrocatalysis is possible with monomolecular and multimolecular layers of the redox substance. The electron transfer mediation can assume several special forms; these are identified and experimental examples are given. The differences between electrocatalytic behaviour of monomolecular and multimolecular layers are discussed; electrocatalysis in the latter circumstance can include reaction rate elements of electrochemical charge and substrate migration through the multilayer in addition to the chemical rate. Theoretical ideas are presented that interconnect these three rate elements, to show that either all of the multilayer sites can participate in the electrocatalytic reaction, or only about the equivalent of a monolayer, depending on the relative rates of the electrochemical charge transport, the diffusion of substrate, and the chemical reaction rate.
Labour Market Transitions and the Erosion of the Fordist Lifecycle: Discarding Older Workers in the Automobile Manufacturing and Banking Industries in the United States

The automobile manufacturing and banking industries provide ideal contrasting cases for analysing the changing nature of the employment contract and the resultant effect on older workers. In the auto industry the main thrust of firm activity has been to discard older workers who are viewed as dispensable because of their higher wages and health care costs compared to younger workers. The primary tactics employed have been to offer early retirement incentives and to extend overtime to older workers during periods of production increases instead of hiring younger workers. The prospect of a lengthy working week provides an additional incentive for older workers to retire. In the banking industry, older workers are viewed as costly and untrainable, and bank managers have taken every opportunity to discard them. In different ways, both industries illustrate a more general lack of concern with older workers as evidenced by the absence of worker retraining programmes and government efforts to encourage older worker retention in the U.S.
Tree-based group key agreement

Secure and reliable group communication is an active area of research. Its popularity is fueled by the growing importance of group-oriented and collaborative applications. The central research challenge is secure and efficient group key management. While centralized methods are often appropriate for key distribution in large multicast-style groups, many collaborative group settings require distributed key agreement techniques. This work investigates a novel group key agreement approach which blends key trees with Diffie--Hellman key exchange. It yields a secure protocol suite called Tree-based Group Diffie--Hellman (TGDH) that is both simple and fault-tolerant. Moreover, the efficiency of TGDH appreciably surpasses that of prior art.
Two-Photon Processes in Colliding-Beam Experiments

The general structure of the two-photon process in colliding-beam experiments, $e+e\ensuremath{\rightarrow}e+e+\ensuremath{\Gamma}$, is studied for an arbitrary hadron final state $\ensuremath{\Gamma}$. The dependence of the scattering amplitudes on the lepton variables are explicitly factored out from the helicity amplitudes for the basic (hadronic) process $\ensuremath{\gamma}+\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\Gamma}$. General formulas are given for the differential cross section as well as for important special cases. The most important inclusive channel ($\ensuremath{\gamma}+\ensuremath{\gamma}\ensuremath{\rightarrow}\mathrm{anything}$) and exclusive channel ($\ensuremath{\gamma}+\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\pi}+\ensuremath{\pi}$) are studied in some detail. The first case can yield information on the fundamental process $\ensuremath{\gamma}+\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\gamma}+\ensuremath{\gamma}$. The second case provides a clean method for extracting the $S$-wave $\ensuremath{\pi}\ensuremath{-}\ensuremath{\pi}$ phase shifts.
Living with uncertainty

The persistence of highly endemic parasitic, bacterial and viral diseases makes individuals and populations vulnerable to emerging and re-emerging diseases. Evaluating the role of multiple component, often interacting, causes of disease may be impossible with research tools designed to isolate single causes. Similarly, it may not be possible to identify statistically significant treatment effects, even for interventions known to be effective, when multiple morbidities are present. Evidence continues to accumulate that nutritional deficiencies, bacterial, viral and parasitic coinfections accelerate HIV transmission. Inclusion of antiparasitics and other beneficial interventions in HIV-prevention protocols is impeded by reliance on inappropriate methodologies. Lack of full scientific certainty is not a reason for postponing safe, cost-effective measures to prevent irreversible damage.
Auxiliary-boson and DMFT studies of bond ordering instabilities of \(t\)-\(J\)-\(V\) models on the square lattice

We examine the influence of strong on-site Coulomb interactions on instabilities of the metallic state on the square lattice to general forms of bond order. The Mott correlations are accounted for by the auxiliary-boson method, and by dynamical mean field theory calculations, complementing our recent work using Gutzwiller projected variational wavefunctions. By the present methods, we find that the on-site Mott correlations do not significantly modify the structure of the bond ordering instabilities which preserve time-reversal symmetry, but they do enhance the instability towards time-reversal symmetry breaking “staggered flux” states.
Improved Distances to Type Ia Supernovae with Multicolor Light-Curve Shapes: MLCS2k2

We present an updated version of the multicolor light-curve shape method to measure distances to Type Ia supernovae (SNe Ia), incorporating new procedures for K-correction and extinction corrections. We also develop a simple model to disentangle intrinsic color variations and reddening by dust and expand the method to incorporate U-band light curves and to more easily accommodate prior constraints on any of the model parameters. We apply this method to 133 nearby SNe Ia, including 95 objects in the Hubble flow (cz ≥ 2500 km s-1), which give an intrinsic dispersion of less than 7% in distance. The Hubble flow sample, which is of critical importance to all cosmological uses of SNe Ia, is the largest ever presented with homogeneous distances. We find that the Hubble flow SNe with H0dSN ≥ 7400 km s-1 yield an expansion rate that is 6.5% ± 1.8% lower than the rate determined from SNe within that distance, and this can have a large effect on measurements of the dark energy equation of state with SNe Ia. Peculiar velocities of SN Ia host galaxies in the rest frame of the Local Group are consistent with the dipole measured in the cosmic microwave background. Direct fits of SNe Ia that are significantly reddened by dust in their host galaxies suggest that their mean extinction law may be described by RV 2.7, but optical colors alone provide weak constraints on RV.
Concurrent trading in two experimental markets with demand interdependence

We report results from fifteen computerized double auctions with concurrent trading of two commodities. In contrast to prior experimental markets, buyers’ demands are induced via CES earnings functions defined over the two traded goods, with a fiat money expenditure constraint. Sellers receive independent marginal cost arrays for each commodity. Parameters for buyers” earnings functions and sellers’ costs are set to yield a stable, competitive equilibrium. In spite of the complexity introduced by the demand interdependence, the competitive model is a good predictor of market outcomes, although prices tend to be above (below) the competitive prediction in the low-price (high-price) market.
Spacecraft computer resource margin management

The conduction of the Project Galileo Orbiter, with 18 microcomputers and the equivalent of 360K 8-bit bytes of memory contained within two major engineering subsystems and eight science instruments, requires that the key onboard computer system resources be managed in a very rigorous manner. Attention is given to the rationale behind the project policy, the development stage, the preliminary design stage, the design/implementation stage, and the optimization or 'scrubbing' stage. The implementation of the policy is discussed, taking into account the development of the Attitude and Articulation Control Subsystem (AACS) and the Command and Data Subsystem (CDS), the reporting of margin status, and the response to allocation oversubscription.
Enthalpy recovery of polymeric glasses: Is the theoretical limiting liquid line reached?

Abstract Glasses are inherently non-equilibrium materials, and consequently, their properties evolve toward equilibrium in a process known as structural recovery or physical aging. Recently, several authors have suggested that the equilibrium liquid line is not reached even when properties have ceased to evolve. In this work, we present measurements of the enthalpy recovery of polystyrene (PS) at temperatures ranging from 90.0 to 103.0 °C, for aging times up to 200 days. The results are analyzed in the context of the TNM model of structural recovery. In addition, we analyze data in the literature to determine whether enthalpy recovery ceases prior to the material reaching the equilibrium liquid line obtained by extrapolation of the liquid line above Tg. The results suggest that, in fact, the liquid enthalpy line is reached at temperatures below Tg when equilibrium is reached, i.e. when properties cease to evolve.
Effects of Radiation Exposure on Glass Alteration in a Steam Environment

Several Savannah River Plant (SRL) glass compositions were reacted in steam at temperatures of 150 to 200{degrees}C. Half of the tests utilized actinide-doped monoliths and were exposed to an external ionizing gamma source, while the remainder were doped only with U and reacted without gamma exposure. All glass samples readily reacted to form secondary mineral phases within the first week of testing. An in situ layer of smectite initially developed on nonirradiated SRL 202 glass test samples. After 21 days, a thin layer of illite was precipitated from solution onto the smectite layer. A number of alteration products including zeolite, Casilicate, and alkali or alkaline earth uranyl silicate phases were also distributed over most sample surfaces. In the irradiated SRL 202 glass tests, up to three layers enveloped rounded, and sometimes fractured, glass cores. After 35 to 56 days these remnant cores were replaced by a mottled or banded Fe- and Si-rich material. The formation of some secondary mineral phases also has been accelerated in the irradiated tests, and in some instances, the irradiated environment may have led to the precipitation of a different suite of minerals. The alteration layer(s) developed at rates of 2.3 and 32 {mu}m/day for the nonirradiated and irradiated SRL 202 glasses, respectively, indicating that layer development is accelerated by a factor of {approximately} 10 to 15X due to radiation exposure under the test conditions.
High-resolution infrared spectroscopy of formamide and deuterated formamide in a molecular beam

High-resolution infrared spectra of formamide and deuterated formamide (DCONH2) were collected by molecular-beam optothermal spectroscopy. The spectrum of formamide was found to be perturbed such that each rotational transition was split into two peaks. The splitting was absent in the spectrum of deuterated formamide. The large splitting in the spectrum of formamide (~0.7 cm−1) prevented an accurate deconvolution of the spectrum into zeroth-order bright and dark states. A list of the possible coupling modes is presented. The coupling, however, is not well represented as a simple coupling of two rigid rotors.
Designing for automated construction

The majority of automated construction research and development has been bottom-up, from the construction/engineering side rather than top-down from the design end. Section 2 of this paper looks at precedents in automated construction research and identifies an apparent gap in design related themes. Section 3 is devoted to the introduction of a research programme which addressed topics related to the conceptual design of robotic systems for construction, and developing overall design principles for top-down architect/designer applications. The research included the derivation of simple shape grammars and a simulation research programme for understanding component connections and robotic manipulation, using a model robotic construction system remote controlled over the Internet. Section 4 presents a report of the research carried out according to the programme, and introduces an example concept automated construction system designed according to the principles derived from the investigation outlined in Section 3.
Type I noise storms and the structure of the extreme ultraviolet corona

The spatial fine structure of the solar corona as observed in the EUV line Fexv is compared with the occurrence of major type I metric noise storms. In all cases, strong changes in the loop structure of the corona are observed. On the disk, these coronal changes are correlated to the emergence of new magnetic flux in the vicinity of existing large active regions. The reverse is demonstrated: during noise storm free periods no coronal changes can be observed. Noise storms at the limb seem to originate in open field configurations over active regions. In all cases, reconnection of coronal magnetic fields over large distances are the cause of noise storms rather than changes of magnetic fields within an active region. Noise storms disappear or are weak at the limb because of foreground absorption in chains of active regions. The observed intensities of active region loops at the limb show that a density of 1.3 × 109 cm−3 which corresponds to a plasma frequency of 100 MHz can occur over a wide variety of altitudes because active region loops are not in hydrostatic equilibrium.
Slouching Toward Managed Care Liability: Reflections on Doctrinal Boundaries, Paradigm Shifts, and Incremental Reform

Following the seemingly endless debate over managed care liability, I cannot suppress thoughts of Yeats’s poem, “The Second Coming.” It is not the wellknown phrase, “Things fall apart; the centre cannot hold,” that comes to mind; although that could describe the feeling of a health-care system unraveling. The poem’s depiction of lost innocence — “The best lack all conviction, while the worst/Are full of passionate intensity” — does not allude to the legislature, the industry, the public, or the medical or legal profession. What resonates is the poem’s evocation of humanity’s cyclical history of expectation and disappointment, with ideas as grand as justice and occupations as pedestrian as managed care. Writing in 1919, Yeats described the end of an era with images of war’s destructive forces. The poem expresses a universal desire for some miraculous rebirth or resolution of all problems: “Surely some revelation is at hand.” But instead, the brutish Sphinx-like creature emerges, possibly the Antichrist. New gods displace old gods in the cycle of civilization, and man must muddle on.
Jean van Heijenoort’s Contributions to Proof Theory and Its History

Jean van Heijenoort was best known for his editorial work in the history of mathematical logic. I survey his contributions to model-theoretic proof theory, and in particular to the falsifiability tree method. This work of van Heijenoort’s is not widely known, and much of it remains unpublished. A complete list of van Heijenoort’s unpublished writings on tableaux methods and related work in proof theory is appended.
ONE-COMPLEMENTED SUBSPACES OF REAL SEQUENCE SPACES

Characterizations are given for 1-complemented hyperplanes of strictly monotone real Lorentz spaces and 1-complemented finite codimensional subspaces (which contain at least one basis element) of real Orlicz spaces equipped with either Luxemburg or Orlicz norm.
Thermodynamics of Insulated Pressure Vessels for Vehicular Hydrogen Storage

This paper studies the application of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH 2 ); low-temperature (46 K) compressed hydrogen (CH 2 ), or ambient-temperature CH 2 . In this analysis, hydrogen temperatures, pressures, and venting losses are calculated for insulated pressure vessels fueled with LH 2 or with low-temperature CH 2 , and the results are compared to those obtained in low-pressure LH 2 tanks. Hydrogen losses are calculated as a function of daily driving distance during normal operation; as a function of time during long periods of vehicle inactivity; and as a function of initial vessel temperature during fueling. The results show that insulated pressure vessels have packaging characteristics comparable or better than those of conventional, low-pressure LH 2 tanks, with greatly improved dormancy and much lower boil-off, and therefore appear to be a good alternative for vehicular hydrogen storage.
Gauge Symmetries of the N=2 String

Abstract We study the underlying gauge symmetry algebra of the N = 2 string, which is broken down to a subalgebra in any spacetime background. For given toroidal backgrounds, the unbroken gauge symmetries (corresponding to holomorphic and antiholomorphic worldsheet currents) generate area-preserving diffeomorphism algebras of null 2-tori. A minimal Lie algebraic closure, containing all the gauge symmetries that arise in this way, is the background-independent volume-preserving diffeomorphism algebra of the target Narain torus T4,4. The underlying symmetries act on the ground ring of functions on T4,4 as derivations, much as in the case of the d = 2 string. A background-independent spacetime action valid for noncompact metrics is presented, whose symmetries are volume-preserving diffeomorphisms. Possible extensions to N = 2 and N = 1 heterotic strings are briefly discussed.
Gravitational lensing signatures of supermassive black holes in future radio surveys

Observational measurements of the relationship between supermassive black holes (SMBHs) and the properties of their host galaxies are an important method for probing theoretical hierarchical growth models. Gravitational lensing is a unique mechanism for acquiring this information in systems at cosmologically significant redshifts. We review the calculations required to include SMBHs in two standard galactic lens models, a cored isothermal sphere and a broken power law. The presence of the SMBH produces two primary effects depending on the lens configuration, either blocking the ‘‘core’’ image that is usually predicted to form from a softened lens model or adding an extra, highly demagnified image to the predictions of the unaltered lens model. The magnitudes of these effects are very sensitive to galaxy core sizes and SMBH masses. Therefore, observations of these lenses would probe the properties of the inner regions of galaxies, including their SMBHs. Lensing cross sections and optical depth calculations indicate that to fully observe these characteristic signatures, flux ratios of order 10 6 or more between the brightest and faintest images of the lens must be detectable, and thus, the next generation of radio telescope technology offers the first opportunity for a serious observational campaign. Core images, however, are already detectable, and with additional observations their statistics may be used to guide future SMBH searches. Subject headings: black hole physics — galaxies: evolution — gravitational lensing — surveys — telescopes
On the measurement and analysis of aggregate economic activity for China: the coincident economic indicators approach

This paper reviews some of China's high-frequency economic indicators and our principal findings on their selection and use. Our aim is to develop a composite index of coincident economic indicators (coincident economic index, CEI) which can be used to obtain timely information on the present state of the China's economy and provide an appropriate measure to analyze China's short-term macroeconomic dynamics. Notably, combining industrial production, retail sales, manufacturing employment, income of financial institutions and passenger traffic volume, they work well as the method for dating business cycles for China. It shows that, over the past two decades, there was one marked recession which occurred in 1988:8 to 1989:12. In addition to this business cycle chronology we also develop a growth cycle chronology based on the deviations from trend of the CE which shows that there have been four cyclical slowdowns since 1986. Whereas GDP growth lacks cyclical movements and appears to be dominated by trend and...
Spectomycins, new antibacterial compounds produced by Streptomyces spectabilis : isolation, structures, and biosynthesis

Three new tetrahydroanthracene antibiotics have been isolated from modified culture broths of Streptomyces spectabilis. The new compounds, spectomycins Al, A2 and Bl, exist as monomeric (C20H20O7, Al; C19H18O7, A2) and as symmetrical dimeric (C38H34O14; Bl) forms. Only spectomycin Bl has moderate activity against Gram-positive microorganisms. We report here the structure elucidation and biosynthetic origin of these compounds.
On the precision of public information and mutual fund performance

I show that mutual fund managers who adjust their portfolio holdings based on changes in the variation of analyst forecasts achieve significantly lower abnormal returns. Utilizing a partially revealing rational expectations equilibrium (REE) setup, I show that an uninformed (hence, unskilled) investor places greater weight on the public signal relative to an informed investor, given an increase in the precision of public information. Following Kacperczyk and Seru, I formulate a new measure of managerial skill based on the standard deviation of analyst recommendations. This measure, dubbed RPI σ , captures the sensitivity of changes in mutual fund portfolio holdings because of changes in the standard deviation of analyst forecasts. Statistical evidence shows that abnormal returns decrease in RPI σ . The results are robust to various conventional performance benchmarks and alternative formulations of RPI σ using analyst price targets, earnings per share forecasts and coefficients of variation.
Varadhan estimates for rough differential equations driven by fractional Brownian motions

In this work we study rough differential equations driven by a fractional Brownian motion with Hurst parameter H>14 and establish Varadhan’s small time estimates for the density of solutions of such equations under Hormander’s type conditions.
Homogeneous catalysis of the hydrogenation of 9,10- dimethylanthracene to 1,2-dihydro-9,10-dimethylanthracene by [RuH(PPh3)2(9,10-dimethylanthracene)]+

Abstract The cationic ruthenium arene complex, [RuH(PPh3)2(η6-9,10-dimethylanthracene)]+ (1), serves as a catalyst for the hydrogenation of 9,10-dimethylanthracene (2), initially to 1,2-dihydro-9,10-dimethyl- anthracene (3), followed by hydrogenation of the latter to 1,2,3,4-tetrahydro-9,10-dimethylanthracene (4). The first step, i.e., 2 → 3, obeys the rate-law −d[2]/dt = kcat[1][H2], where kcat = (1.5±0.1)×10−3 M−1 s−1 at 25°C in CDCl3.
Thermal electron heating rate: A derivation

The thermal electron heating rate is an important heat source term in the ionospheric electron energy balance equation, representing heating by photoelectrons or by precipitating higher energy electrons. A formula for the thermal electron heating rate is derived from the kinetic equation using the electron-electron collision operator as given by the unified theory of Kihara and Aono. This collision operator includes collective interactions to produce a finite collision operator with an exact Coulomb logarithm term. The derived heating rate O(e) is the sum of three terms, O(e) = O(p) + S + O(int), which are respectively: (1) primary electron production term giving the heating from newly created electrons that have not yet suffered collisions with the ambient electrons; (2) a heating term evaluated on the energy surface m(e)/2 = E(T) at the transition between Maxwellian and tail electrons at E(T); and (3) the integral term representing heating of Maxwellian electrons by energetic tail electrons at energies ET. Published ionospheric electron temperature studies used only the integral term O(int) with differing lower integration limits. Use of the incomplete heating rate could lead to erroneous conclusions regarding electron heat balance, since O(e) is greater than O(int) by as much as a factor of two.
A data base management facility for automatic generation of data base managers

This paper presents a facility for the implementation of data base management systems having high degrees of horizontal data independence, i.e. independence from chosen logical properties of a data base as opposed to vertical independence from storage structures. The facility consists of a high level language for the specification of virtual data base managers, a compiler from this language to a pseudo-machine language, and an interpreter for the pseudo-machine language.It is shown how this facility can be used to produce efficient data base management systems with any degree of both horizontal and vertical data independence. Two key features of this tool are the compilation of tailored data base managers from individual schemas and multiple levels of optional binding.
Dynamic Programming: An Introduction by Example

The author introduces some basic dynamic programming techniques, using examples, with the help of the computer algebra system Maple. The emphasis is on building confidence and intuition for the solution of dynamic problems in economics. To integrate the material better, the same examples are used to introduce different techniques. One covers the optimal extraction of a natural resource, another uses consumer utility maximization, and the final example solves a simple real business cycle model. Every example is accompanied by Maple computer code to allow for replication.
A uniform approach to software and hardware fault tolerance

Abstract In recent years, various attempts have been made to combine software and hardware fault tolerance in critical computer systems. In these systems, software and hardware faults may occur in many different sequences. The problem of how to incorporate these sequences in a fault-tolerant system design has been largely neglected in previous work. In this article, a uniform software-based fault tolerance method is proposed to distinguish and tolerate various sequences of software and hardware faults. This method can be based on the recovery block or the n-version programming scheme, two fundamental software fault tolerance schemes. The concept of fault identification and system reconfiguration tree is proposed to represent the procedure of fault identification and system reconfiguration in a systematic way.
Enteropathogenic Escherichia coli prevalence in laboratory rabbits

Rabbit-origin enteropathogenic Escherichia coli (EPEC) causes substantial diarrhea-associated morbidity and has zoonotic potential. A culture-based survey was undertaken to ascertain its prevalence. EPEC was isolated from 6/141 (4.3%) commercially-acquired laboratory rabbits. Three of these did not have diarrhea or EPEC-typical intestinal lesions; they instead had background plasmacytic intestinal inflammation. Asymptomatically infected rabbits may function as EPEC reservoirs.
On the Middle Coefficient of a Cyclotomic Polynomial

Clearly (, has degree 0 (n), where 0 signifies Euler's totient function. These monic polynomials can be defined recursively as (I1 (x) = x 1 and Hiln D (x) = xn 1 for n > 1. The first few are easily calculated to be x 1, x + 1, x2 + x + , x2 + 1.... For these and other basic facts, see an algebra text such as [5]. While it might appear that the coefficients of the cyclotomic polynomials are always ?1, the presence of 2x7 in o105(x) shows that this is not invariably the case (and indeed is a good counterexample for those students who insist that the "law of small numbers" is universally valid; see [4] for further discussion). Naturally, much work has been done on the values of the coefficients of On (x). One amazing fact worthy of mention is that every integer appears as a coefficient in some cyclotomic polynomial (see [1], [8]). In this article, we provide a short and elementary proof of the following result: