cssi/SciSciGPT-SciSciNet huggingface dataset:
Biomechanics of the human chest, abdomen, and pelvis in lateral impact

Fourteen unembalmed cadavers were subjected to 44 blunt lateral impacts at velocities of approximately 4.5, 6.7, or 9.4 m/s with a 15 cm flat circular interface on a 23.4 kg pendulum accelerated to impact speed by a pneumatic impactor. Chest and abdominal injuries consisted primarily of rib fractures, with a few cases of lung or liver laceration in the highest severity impacts. There were two cases of pubic ramus fracture in the pelvic impacts. Logist analysis of the biomechanical responses and injury indicated that the maximum Viscous response had a slightly better correlation with injury than maximum compression for chest and abdominal impacts. A tolerance level of VC = 1.47 m/s for the chest and VC = 1.98 m/s for the abdomen were determined for a 25% probability of critical injury. Maximum compression was similarly set at C = 38% for the chest and at C = 44% for the abdomen. The experiments indicate that chest and abdominal injury may occur by a viscous mechanism during the rapid phase of body compression, and that the Viscous and compression responses are effective, complementary measures of injury risk in side impact. Although serious pelvic injury was infrequent, lateral public ramus fracture correlated with compression of the pelvis, not impact force or pelvic acceleration. Pelvic tolerance was set at 27% compression.
Current fluctuations in a single tunnel junction

We study current fluctuations in a single tunnel junction. The effect of external leads and of the Coulomb interaction is incorporated in the calculation. We obtain the fluctuations at the tunneling barrier of the junction and at the leads. It is shown that the two fluctuations have different noise spectra, and that the relation between them is nontrivial. The origin of the difference is discussed and the results are compared with recent experiments. \textcopyright{} 1996 The American Physical Society.
OCEAN ACIDIFICATION NOT LIKELY TO AFFECT THE SURVIVAL AND FITNESS OF TWO TEMPERATE BENTHIC FORAMINIFERAL SPECIES: RESULTS FROM CULTURE EXPERIMENTS

Specimens of Bolivina argentea and Bulimina marginata , two widely distributed temperate benthic foraminiferal species, were cultured at constant temperature and controlled p CO2 (ambient, 1000 ppmv, and 2000 ppmv) for six weeks to assess the effect of elevated atmospheric CO2 concentrations on survival and fitness using Adenosine Triphosphate (ATP) analyses and on shell microfabric using high-resolution SEM and image analysis. To characterize the carbonate chemistry of the incubation seawater, total alkalinity and dissolved inorganic carbon were measured approximately every two weeks. Survival and fitness were not directly affected by elevated p CO2 and the concomitant decrease in seawater pH and calcite saturation states (Ωc), even when seawater was undersaturated with respect to calcite. These results differ from some previous observations that ocean acidification can cause a variety of effects on benthic foraminifera, including test dissolution, decreased growth, and mottling (loss of symbiont color in symbiont-bearing species), suggesting that the benthic foraminiferal response to ocean acidification may be species specific. If so, this implies that ocean acidification may lead to ecological winners and losers even within the same taxonomic group.
Dihydrogen complexes as prototypes for the coordination chemistry of saturated molecules.

Abstract The binding of a dihydrogen molecule (H2) to a transition metal center in an organometallic complex was a major discovery because it changed the way chemists think about the reactivity of molecules with chemically “inert” strong bonds such as HH and CH. Before the seminal finding of side-on bonded H2 in W(CO)3(PR3)2(H2), it was generally believed that H2 could not bind to another atom in stable fashion and would split into two separate H atoms to form a metal dihydride before undergoing chemical reaction. Metal-bound saturated molecules such as H2, silanes, and alkanes (σ-complexes) have a chemistry of their own, with surprisingly varied structures, bonding, and dynamics. H2 complexes are of increased relevance for H2 production and storage in the hydrogen economy of the future.
Catalyst Type and Concentration Dependence in Catalytic Transfer Hydrogenolysis of α,β-Unsaturated Carbonyls and Nitriles Via Ammonium Formate

Abstract The catalytic reduction of a variety of α, β-unsaturated compounds into saturated analogs in the presence of other reducible moieties is described using ammonium formate as a hydrogen source. The rate dependence on the concentration of Pd-C catalyst as well as on 5% Pd-BaSO4 and Ra-Ni are also characterized.
Hall Polynomials via Automorphisms of Short Exact Sequences

We present a sum-product formula for the classical Hall polynomial which is based on tableaux that have been introduced by T. Klein in 1969. In the formula, each summand corresponds to a Klein tableau, while the product is taken over the cardinalities of automorphism groups of short exact sequences which are derived from the tableau. For each such sequence, one can read off from the tableau the summands in an indecomposable decomposition, and the size of their homomorphism and automorphism groups. Klein tableaux are refinements of Littlewood–Richardson tableaux in the sense that each entry l ≥ 2 carries a subscript r. We describe module theoretic and categorical properties shared by short exact sequences which have the same symbol lr in a given row in their Klein tableau. Moreover, we determine the interval in the Auslander–Reiten quiver in which the indecomposable sequences of pn-bounded groups which carry such a symbol occur.
Synthesis of 3′-deuterated pyrimidine nucleosides via stereoselective reduction of a protected 3-oxoribose

Abstract Thymidine ( 2 ) and 5-methyl-2′- O -( t -butyldimethylsilyl)uridine ( 3 ) deuterated at the C3′-position were prepared with complete stereocontrol via NaB 2 H 4 reduction of a 3-oxoribose derivative ( 5 ). Utilization of benzyl protecting groups in the deuterated glycosidation substrate facilitates the synthesis of ribonucleosides and 2′-deoxyribonucleosides with minimal protecting group manipulations.
Accounting for fuel price risk when comparing renewable to gas-fired generation: the role of forward natural gas prices

Abstract Unlike natural gas-fired generation, renewable generation (e.g., from wind, solar, and geothermal power) is largely immune to fuel price risk. If ratepayers are rational and value long-term price stability, then—contrary to common practice—any comparison of the levelized cost of renewable to gas-fired generation should be based on a hedged gas price input, rather than an uncertain gas price forecast. This paper compares natural gas prices that can be locked in through futures, swaps, and physical supply contracts to contemporaneous long-term forecasts of spot gas prices. We find that from 2000 to 2003, forward gas prices for terms of 2–10 years have been considerably higher than most contemporaneous long-term gas price forecasts. This difference is striking, and implies that comparisons between renewable and gas-fired generation based on these forecasts over this period have arguably yielded results that are biased in favor of gas-fired generation.
Magnus approximation for K -shell ionization by heavy-ion impact

The Magnus approximation (or sudden approximation) is applied to derive the transition amplitude and the cross section for $K$-shell ionization of atoms by heavy-ion impact. The target electron is described by a hydrogenic wave function and the projectile as a point charge moving along a straight-line trajectory. The transition amplitude for each partial wave of the ejected electron is expressed as an infinite (but rapidly converging) sum over hypergeometric functions. To obtain the total cross section, only integrals over impact parameter and the final electron momentum have to be evaluated numerically. The approach, because it is nonperturbative, should be particularly useful for treating collisions of light atoms with much heavier projectile ions. It also allows the study of the impact-parameter dependence of the ionization process. The connection with the Glauber approximation is pointed out.
Chiral symmetry at finite T, the phase of the Polyakov loop and the spectrum of the Dirac operator

Abstract A recent Monte Carlo study of quenched QCD showed that the chiral condensate is non-vanishing above T c in the phase where the average of the Polyakov loop P is complex. We show how this is related to the dependence of the spectrum of the Dirac operator on the boundary conditions in Euclidean time. We use a random matrix model to calculate the density of small eigenvalues and the chiral condensate as a function of arg P . The chiral symmetry is restored in the arg P = 2π 3 phase at a higher T than in the arg P = 0 phase. In the phase arg P = π of the SU (2) gauge theory the chiral condensate stays nonzero for all T .
Dilepton production in e−p and e+e− colliders

Abstract In an e − p collider, a striking signature for a dilepton gauge boson is e e − p → e + μ − μ − + anything; this cross section is calculated by using the helicity amplitude technique. At HERA, with center-of-mass energy √ s = 314 GeV, a dilepton mass above 150 GeV is inaccessible but at LEPII-LHC, with a center-of-mass energy √ s = 1790 GeV, masses up to 650 GeV can be discovered. In an e + e − collider, the signature is e + e − → 2e + 2 μ − or 2e − 2 μ + . The cross sections of this process are also calculated for the center-of-mass energies √ s = 200, 500 and 1000 GeV.
BBN for pedestrians

The simplest, 'standard' model of Big Bang nucleosynthesis (SBBN) assumes three light neutrinos (Nν = 3) and no significant electron neutrino asymmetry ( asymmetry parameter ξe ≡ μe/kT, where μe is the chemical potential of νe) leaving only one adjustable parameter: the baryon to photon ratio η ≡ nB/nγ. The primordial abundance of any one nuclide can, therefore, be used to measure η and the value derived from the observationally inferred primordial abundance of deuterium closely matches that from current non-BBN data, primarily from the WMAP survey. However, using this same estimate for η, there is a tension between the SBBN-predicted abundances of 4He and 7Li and their current, observationally inferred primordial abundances, suggesting that Nν may differ from the standard model value of three and/or that ξe may differ from zero (or, that systematic errors in the abundance determinations have been underestimated or overlooked). The differences are not large and the allowed ranges of the BBN parameters (η, Nν and ξe) permitted by the data are quite small. Within these ranges, the BBN-predicted abundances of D, 3He, 4He, and 7Li are very smooth, monotonic functions of η10, ΔNν ≡ Nν − 3 and ξe. As a result, it is possible to describe the dependence of these abundances (or powers of them) upon the three parameters by simple, linear fits which, over their ranges of applicability, are accurate to a few per cent or even better. The fits presented here have not been maximized for their accuracy but, rather, for their simplicity. To identify the ranges of applicability and relative accuracies, they are compared with detailed BBN calculations; their utility is illustrated with several examples. Given the tension within BBN, these fits should prove useful in facilitating studies of the viability of various options for non-standard physics and cosmology, prior to undertaking detailed BBN calculations.
Rotating storage devices as partially associative memories

"Associativity" is a highly desirable property of memory devices. Unfortunately, it does not seem to fit very well into the structure of contemporary randomaccess memories. A realization of associativity on such memories is always involved with high density of logic, and in today's technology is bound to be very expensive. Virtually all existing implementations of associative memories are accordingly on a very small scale and are typically used for special purposes such as the support of "virtual memory" schemes. From this situation one can get the impression that large scale associative memories are impractical. Fortunately, however, it turns out that rotating memories, unlike random access memories, are very natural hosts for at least a limited degree of associative addressing.
Few-Photon Single-Atom Cavity QED With Input-Output Formalism in Fock Space

The Jaynes-Cummings (JC) system, which describes the interaction between a cavity and a two-level atom, is one of the most important systems in quantum optics. We obtain analytic solutions for the one- and two-photon transport in a waveguide side-coupled to the JC system using input-output formalism in Fock space. With these results, we discuss the conditions under which the JC system functions as a photon switch for waveguide photons in both the strong and weak coupling regimes.
Application of frequency-domain handling qualities criteria to the longitudinal landing task

Under NASA sponsorship, an in-flight simulation of the longitudinal handling qualities of several configurations for the approach and landing tasks was performed on the USAF/AFWAL Total In-Flight Simulator by the Calspan Corporation. The basic configuration was a generic transport airplane with static instability. The control laws included proportional plus integral gain loops to produce pitch-rate and angle-of-attack feedback loops. The evaluation task was a conventional visual approach to a flared touchdown at a designated spot on the runway with a lateral offset. The general conclusions were that the existing criteria are based on pitch-attitude response and that these characteristics do not adequately discriminate between the good and bad configurations of this study. This paper describes the work that has been done to further develop frequency-based criteria in an effort to provide better correlation with the observed data.
Momentum Thickness Measurements for Thick Axisymmetric Turbulent Boundary Layers

Experimental measurements of the mean wall shear stress and boundary layer momentum thickness on long, thin cylindrical bodies are presented. To date, the spatial growth of the boundary layer and the related boundary layer parameters have not been measured for cases where δ/a (a =cylinder radius) is much greater than one. Moderate Reynolds numbers (10 4 <RE θ <10 5 ) encountered in hydrodynamic applications are considered. Tow tests of cylinders with diameters of 0.61 0.89, and 2.5 mm and lengths ranging from approximately 30 meters to 150 meters were performed. The total drag (axial force) was measured at low speeds up to 17.4 m/sec. These data were used to determine the tangential drag coefficients on each test specimen, which were found to be two to three times greater than the values for the corresponding hypothetical flat-plate cases. Using the drag measurements, the turbulent boundary layer momentum thickness at the downstream end of the cylindrical bodies is determined, using a control volume analysis
Modification of COMMIX-1B for simulation of thermal- and flowfields in ultrahigh temperature vapor core reactor

References Hunter, L. W., and Kuttler, J. R., "The Enthalpy Method for Heat Conduction Problems with Moving Boundaries," Journal of Heat Transfer, Vol. Ill, May 1989, pp: 239-242. Landau, H. G., "Heat Conduction in a Melting Solid," Quarterly Applied Math, Vol. 8, 1950, pp. 81-94. Kirchhoff, G., Vorlesungen uber die Theorie der warme, Earth, Leipzig, Germany, 1984. Crank, J., and Nicolson, P., "A Practical Method of Numerical Evaluation of Solutions of Partial Differential Equations of the Heat Conduction Type," Proceedings of the Cambridge Philosophical Society, Vol. 43, 1947, pp. 50-67. Forsythe, G. E., and Wasow, W. R., Finite-Difference Methods for Partial Differential Equations, Wiley, New York, 1960, Chap. 2. Dongarra, J. J., Bunch, J. R., Moler, C. B., and Stewart, G. W., Unpack User's Guide, SIAM, Philadelphia, 1979. Randall, J. D., "Numerical Solution of the Embedding Equations Applied to the Landau Melting Problem," International Journal of Heat and Mass Transfer, Vol. 21, 1978, pp. 1447-1449.
Long-range exciton coupling from dipyrrinone chromophores

Abstract Dipyrrinone chromophores, attached by their acid termini to give (1 R ,2 R )-cyclohexanediol dipropionate and diacetate esters (xanthobilirubinate and nor-xanthobilirubinate, respectively), interact through exciton coupling, as evidenced by intense bisignate circular dichroism Cotton effects for the pigment's long wavelength transition. The bis-xanthobilirubinate exhibits the expected negative exciton chirality (Δϵ max 439 -16, Δϵ max 382 +22, CH 2 Cl 2 ) but the bis-norxanthobilirubinate exhibits positive exciton chirality (Δϵ max 420 +38, Δϵ max 367 -46, CH 2 Cl 2 ).
Delay to major street through vehicles at two-way stop-controlled intersections

Abstract This paper describes a methodology for predicting the delay to major street through vehicles at two-way stop-controlled intersections. This delay is incurred when major street left-turn demand exceeds the available storage area and blocks the adjacent through lane. The through lane blockage problem does not generally occur with significant frequency on streets with divided cross sections that have left-turn bays or lanes; however, it frequently occurs on undivided streets due to their lack of left-turn storage. To minimize this delay, through drivers often merge with vehicles in the adjacent through lane—if there is an adequate gap for them to safely merge into. If there is no merge opportunity, then the through drivers will stay in the inside lane until the queue ahead dissipates. The through vehicle delay predicted by the methodology was found to be relatively small (i.e. less than 5 s veh−1) when compared with delays commonly incurred by non-priority movements at unsignalized intersections. However, when expressed in terms of total vehicle hours of delay, the effect can be quite significant. In general, through vehicle delay increases with increasing approach flow rate and left-turn percentage. However, at flow rates in excess of about 1400 veh h−1, delays increase very rapidly and there is evidence that larger left-turn percentages may have lower delays. ©
Extended supersymmetry with gauged central charge

Abstract Global N = 2 supersymmetry in four dimensions with a gauged central charge is formulated in superspace. To find an irreducible representation of supersymmetry for the gauge connections a set of constraints is given. Then the Bianchi identities are solved subject to this set of constraints. It is shown that the gauge connection of the central charge is a N = 2 vector multiplet. Moreover the Bogomol'nyi bound of the massive particle states is studied.
A two-level reconfigurable architecture for digital signal processing

This paper describes a novel reconfigurable architecture for digital signal processing (DSP). This architecture consists of a two-level array of cells and interconnections. On the upper level, fundamental DSP operations such as multiplication and addition are mapped onto blocks of 4-bit cells. On the lower level, each cell uses a 4x4 matrix of smaller ''elements'' to perform the necessary computations. Cells also contain pipeline latches for increased throughput. The architecture features a simple VLSI implementation that combines the flexibility of memory elements with the speed of DOMINO logic. Initial prototypes have been fabricated using a modest [email protected] CMOS technology. Circuit simulations of the cell in [email protected] technology indicate that the design achieves a clock frequency of 200MHz.
Review of uranyl mineral solubility measurements

The solubility of uranyl minerals controls the transport and distribution of uranium in many oxidizing environments. Uranyl minerals form as secondary phases within uranium deposits, and they also represent important sinks for uranium and other radionuclides in nuclear waste repository settings and at sites of uranium groundwater contamination. Standard state Gibbs free energies of formation can be used to describe the solubility of uranyl minerals; therefore, models of the distribution and mobility of uranium in the environment require accurate determination of the Gibbs free energies of formation for a wide range of relevant uranyl minerals. Despite decades of study, the thermodynamic properties for many environmentally-important uranyl minerals are still not well constrained. In this review, we describe the necessary elements for rigorous solubility experiments that can be used to define Gibbs free energies of formation; we summarize published solubility data, point out difficulties in conducting uranyl mineral solubility experiments, and identify areas of future research necessary to construct an internally-consistent thermodynamic database for uranyl minerals.
X-ray tomography system to investigate granular materials during mechanical loading.

We integrate a small and portable medical x-ray device with mechanical testing equipment to enable in situ, non-invasive measurements of a granular material's response to mechanical loading. We employ an orthopedic C-arm as the x-ray source and detector to image samples mounted in the materials tester. We discuss the design of a custom rotation stage, which allows for sample rotation and tomographic reconstruction under applied compressive stress. We then discuss the calibration of the system for 3D computed tomography, as well as the subsequent image reconstruction process. Using this system to reconstruct packings of 3D-printed particles, we resolve packing features with 0.52 mm resolution in a (60 mm)3 field of view. By analyzing the performance bounds of the system, we demonstrate that the reconstructions exhibit only moderate noise.
A convenient synthesis of 1,4,7,10,13-pentaazacyclopentadecane

Abstract Cyclic pentamine 1 was synthesized in good yields from fragments containing two and three nitrogen atoms.
Amorphic association schemes with negative Latin square-type graphs

Applying results from partial difference sets, quadratic forms, and recent results of Brouwer and Van Dam, we construct the first known amorphic association scheme with negative Latin square-type graphs and whose underlying set is a nonelementary abelian 2-group. We give a simple proof of a result of Hamilton that generalizes Brouwer's result. We use multiple distinct quadratic forms to construct amorphic association schemes with a large number of classes.
Signed line intercept count

SUMMARY Elements of surfaces that bound a phase (β) in a two phase mixture (α+β) may be classified as: (a) convex (++) if both principal curvatures are positive; (b) concave (− −) if both are negative; and (c) saddle (+ −) if one is positive and the other negative. This classification excludes the limiting cases for which one or both of the principal curvatures is zero. The traces of these surfaces that form the boundaries of the β areas on a representative two dimensional section may also be: (a) convex (+) if the local curvature is positive; or (b) concave (−) if it is negative. Line intercepts may be tabulated separately for intersections with convex (+) and concave (−) segments of boundary. This paper presents a derivation of fundamental stereological formulae that relate these counting measurements to three-dimensional geometric properties of the structure they sample.
Partial-Order Reduction in Symbolic State-Space Exploration

State-space explosion is a fundamental obstacle in the formal verification of designs and protocols. Several techniques for combating this problem have emerged in the past few years, among which two are significant: partial-order reduction and symbolic state-space search. In asynchronous systems, interleavings of independent concurrent events are equivalent, and only a representative interleaving needs to be explored to verify local properties. Partial-order methods exploit this redundancy and visit only a subset of the reachable states. Symbolic techniques, on the other hand, capture the transition relation of a system and the set of reachable states as boolean functions. In many cases, these functions can be represented compactly using binary decision diagrams (BDDs). Traditionally, the two techniques have been practiced by two different schools—partial-order methods with enumerative depth-first search for the analysis of asynchronous network protocols, and symbolic breadth-first search for the analysis of synchronous hardware designs. We combine both approaches and develop a method for using partial-order reduction techniques in symbolic BDD-based invariant checking. We present theoretical results to prove the correctness of the method, and experimental results to demonstrate its efficacy.
Phases of N=1 supersymmetric gauge theories with flavors

Abstract We explore the phases of N =1 supersymmetric U ( N ) gauge theories with fundamental matter that arise as deformations of N =2 SQCD by the addition of a superpotential for the adjoint chiral multiplet. As the parameters in the superpotential are varied, the vacua of this theory sweep out various branches, which in some cases have multiple semiclassical limits. In such limits, we recover the vacua of various product gauge group theories, with flavors charged under some group factors. We describe in detail the structure of the vacua in both classical and quantum regimes, and develop general techniques such as an addition and a multiplication map which relate vacua of different gauge theories. We also consider possible indices characterizing different branches and potential relationships with matrix models.
Identification of Frequency-Dependent Parameters in a Flexible Rotor System

In a rotor-bearing system, there are usually some under- or unmodeled dynamic components that are considered frequency dependent, such as foundations, bearings, and seals. This paper presents a method to identity the dynamic behavior of these components using an otherwise accurate engineering model of the system in combination with available measurements of system frequency response functions. The approach permits treatment of flexible rotors and allows that the system test excitations and measurement sensors are not collocated. Because all engineering models contain some residual error and all measurements incorporate an element of noise or uncertainty, the quality of the identified parameters must be estimated. This paper introduces application of μ analysis to solve this problem, resulting in acceptable solution time and hard guarantees of solution reliability. Two illustrative examples are provided, showing that the presented approach is an efficient method to identify and bound these parameters.
Temperature Dominance over Human Life.

Temperature bears an importance to man far beyond the mere matter of his hour-to-hour comfort. In some places it lays a heavy, stagnating hand over his life and holds him to a vegetative existence; in others, it generates an energy and progressiveness which drives him forward with irresistible impetus. Its effects begin even before he is conceived, for the metabolic vigor of parental germ cells at the time of their union exerts a potent influence over the entire course of the new life. Without favorable temperatures, neither individual nor nation can develop innate potentialities to the full.
Discussion, construction and evolution: Mill, Buchanan and Hayek on the constitutional order

The paper examines the views of Mill, Hayek, and Buchanan on the role of discussion in the constitutional order. For Mill and Buchanan, the constitutional order itself may be subject to discussion (and change). By contrast, Hayek made the case that the constitutional order is best left unarticulated, outside the realm of public debate and discussion. The question as Hayek posed it is whether there is a role for discussion in “choice of law” the way there is a role for discussion in the “choice of legislation.” For Mill and Buchanan, the answer is yes; but for Hayek, the answer is no. Supposing, with Hayek, that law evolves as a recognized pattern, we inquire about whether the pattern is unique. If multiple sets of experiences or patterns co-exist in society, then any one pattern is an incomplete description of experience and the question arises of whether there is there now a role for the recognition and then discussion of other patterns or laws? We sketch out how a norm of generosity might eventually be brought into a constitutional order as justice, through a process of discussion. We suggest that Hayek’s appeal to government to remedy institutional incompleteness or “degeneration” actually takes him quite close to Mill’s position that discussion can serve to beneficently direct institutional change.
In Situ Heating of the 2007 May 19 CME Ejecta Detected by STEREO/PLASTIC and ACE

In situ measurements of ion charge states can provide unique insight into the heating and evolution of coronal mass ejections (CMEs) when tested against realistic non-equilibrium ionization modeling. In this work, we investigate the representation of the CME magnetic field as an expanding spheromak configuration, where the plasma heating is prescribed by the choice of anomalous resistivity and the spheromak dynamics. We chose as a test case the 2007 May 19 CME observed by STEREO and ACE. The spheromak is an appealing physical model, because the location and degree of heating are fixed by the choice of anomalous resistivity and the spheromak expansion rate which we constrain with observations. This model can provide the heating required between 1.1R ☉ and Earth's orbit to produce charge states observed in the CME flux rope. However, this source of heating in the spheromak alone has difficulty accounting for the rapid heating to Fe8-Fe11+ at lower heights, as observed in STEREO EUVI due to the rapid radiative cooling that occurs at the high densities involved. Episodes of heating and cooling clearly unrelated to spheromak expansion are observed prior to the eruption, and presumably still play a role during the eruption itself. Spheromak heating is also not capable of reproducing the high Fe charge states (Fe16+ and higher) seen in situ exterior to the flux rope in this CME. Thus, while the spheromak configuration may be a valid model for the magnetic topology, other means of energization are still required to provide much of the rapid heating observed.
Nodal quasiparticles versus phase fluctuations in high Tc superconductors: an intermediate scenario

Abstract We explore a BCS Bose Einstein crossover scenario for 0 ≤ T ≤ T c and its implications for the superfluid density and specific heat. The low lying excitations consist of nodal (fermionic) quasi-particles as well as excited (bosonic) pair states. Semi-quantitative comparison with cuprate data is reasonable, with no compelling indications for Landau parameter effects.
COMPANIONS OF THE UNKNOT AND WIDTH ADDITIVITY

It has been conjectured that for knots K and K′ in S3, w(K # K′) = w(K) + w(K′) - 2. In [7], Scharlemann and Thompson proposed potential counterexamples to this conjecture. For every n, they proposed a family of knots $\{K^n_i\}$ for which they conjectured that $w(B^n\, \#\, K^n_i) = w(K^n_i)$ where Bn is a bridge number n knot. We show that for n > 2 none of the knots in $\{K^n_i\}$ produces such counterexamples.
Comparative Analysis of GALLEX-GNO Solar Neutrino Data and SOHO/MDI Helioseismology Data; Further Evidence for Rotational Modulation of the Solar Neutrino Flux

If the solar neutrino flux is variable, the variability could be caused by modulation of the neutrino flux by an inhomogeneous magnetic field in the solar interior. This modulation, which requires nonstandard physics involving a nonzero neutrino magnetic moment, could lead to an oscillation in the detected neutrino flux with a frequency set by the synodic rotation frequency in the region of the solar interior that contains the magnetic structure. We investigate this possibility by carrying out a comparative analysis of the GALLEX-GNO solar neutrino data and estimates of the solar internal rotation rate derived from the MDI helioseismology experiment on the SOHO spacecraft. We first carry out a Lomb-Scargle analysis of the data. There is no significant peak in the spectrum that could be associated with the radiative zone. On the other hand, there are peaks that could be associated with the convection zone. We introduce a statistic, which we evaluate as a function of radius and latitude, that is a measure of the degree of “resonance” of oscillations in the neutrino flux and the synodic solar rotation rate at that radius and latitude. If the oscillations are real and caused by an internal magnetic structure, the resonance statistic will indicate the probable location of that structure. A map of this statistic indicates that the probable location is deep in the convection zone near the equator. We next modify this statistic by integrating it over the equatorial section of the convection zone. This integral resonance statistic provides a measure of the likelihood that the variability of the solar neutrino flux, as measured by the GALLEX-GNO data, has its origin in the equatorial section of the convection zone. We apply the shuffle test, randomly reassigning measurements among runs, to estimate the significance of the value of the statistic computed from the actual data. This test implies that the result is significant at the 0.2% level. When, for comparison, we
Heavy nuclei, from RHIC to the cosmos

Ultra-relativistic heavy ion collisions produce a high-temperature, thermalized system that may mimic the conditions present shortly after the big bang. This writeup will given an overview of early results from the Relativistic Heavy Ion Collider (RHIC), and discuss what we have learned about hot, strongly interacting nuclear systems. The thermal and chemical composition of the system will be discussed, along with observables that are sensitive to the early evolution of the system. I will also discuss the implications of the RHIC results for cosmic ray air showers.
New, practical and effective sources of fluoride ion for desilylation to form carbon anions

Abstract Suspensions of powdered glassy solids prepared by fusion of 1:1 mixtures of CsF-CsOH and CsF-CsCl effectively catalyze the generation of enolates, acetylide and other anions from trimethylsilylated precursors.
3-Trifluoromethylcarbacephems: Synthesis of broad spectrum antibacterial compounds

Abstract The enhanced stability of the carbacephem nucleus over the corresponding cephalosporin nucleus has allowed the synthesis of 7-arylglycyl-3-trifluoromethyl-carbacephems. These unique carbacephems possess broad spectrum activity and high stability to both plasmid and chromosomally mediated s-lactamases.
Conversion of saccharides into formic acid using hydrogen peroxide and a recyclable palladium(II) catalyst in aqueous alkaline media at ambient temperatures

We have developed an effective method that converts a variety of mono- and disaccharides into formic acid predominantly. Our recyclable NHC-amidate palladium(II) catalyst facilitated oxidative degradation of carbohydrates without using excess oxidant. Stoichiometric amounts of hydrogen peroxide and sodium hydroxide were employed at ambient temperatures.
Synthesis of cyclic peptides constrained with biarylamine linkers using buchwald-hartwig C-N coupling

In this paper, we describe the synthesis of conformationally constrained cyclic peptides with biarylamine linkers for peptidomimetics using palladium-catalyzed intramolecular Buchwald-Hartwig C-N coupling. We have prepared a variety of di-, tri-, and tetrapeptides (16-22-membered) in good yields using this reaction.
The Lengthening of Childhood

Over the past 40 years, the age at which children enter first grade has slowly drifted upward. In the fall of 1968, 96 percent of six-year-old children were enrolled in first grade or above. By 2005, the proportion had dropped to 84 percent, mainly because a substantial share of six-year-olds were still in kindergarten. About a third of the increase in age at school entry can be explained by legal changes. Almost every state has increased the age at which children are allowed to start primary school. The other two-thirds of the increase in the age at school entry reflects the individual decisions of parents and teachers who choose to keep children out of kindergarten or first grade even when they are legally eligible to attend. This practice is sometimes called "red-shirting," a phrase originally used to describe the practice of holding college athletes out of play until they have grown larger and stronger. Red-shirting is referred to as "the gift of time" in education circles, reflecting a perception that children who have been allowed to mature for another year will benefit more from their schooling. As we will discuss, little evidence supports this perception. It is indeed true that in any grade, older children tend to perform better academically than the younger children. In the early grades there is a strong, positive relationship between a child's age in months and his performance relative to his peers. But there is little evidence that being older than your classmates has any long-term, positive effect on adult outcomes such as IQ, earnings, or educational attainment. By contrast, there is substantial evidence that entering school later reduces educational attainment (by increasing high school dropout rates) and depresses lifetime earnings (by delaying entry into the labor market).
Crystallization of a Tetrasilicic Fluormica Glass

The crystallization of a tetrasilicic synthetic mica glass of nominal composition K2Mg5Si8O20F4 was investigated at selected temperatures from 560° to 1150°C using DTA, density measurements, electron microscopy, and X-ray diffraction techniques. Crystallization is shown to occur in 2 stages. (1) Initial structural ordering occurs at ∼600°C, as indicated by a strongly exothermic reaction, an increase in density, and the appearance of X-ray diffraction lines. (This transformation temperature is related to fluorine content.) (2) The crystal morphology of the glass-ceramic changes at 900° to 1150°C. A mechanism is proposed for the transformation from amorphous to crystalline structure in this synthetic mica system.
Optimal Control of Engine-Starts for Drivability of Parallel Hybrid Electric Vehicles

The parallel hybrid electric vehicle (HEV) with a single pre-transmission electric motor (the P2 configuration) has a challenging drivability issue during engine-starts because the motor must simultaneously provide the propulsion torque demand and start the engine. The goal of this study is to present a design process to achieve optimal balance between these two conflicting goals. We first develop a control-oriented HEV powertrain model to accurately predict the engine, clutch, and vehicle dynamics. Assuming that the clutch torque can be accurately estimated and perfectly cancelled, an optimal engine-start control problem is formulated to minimize engine-start time while accurately supplying the driver torque demand simultaneously. This nonlinear constrained optimal control problem is solved numerically using Dynamic Programming (DP). DP results show that a proper constant clutch pressure level, which leads to constant torque disturbance that is easy to cancel out using the motor, can achieve near-optimal performance. Furthermore, the DP control policy is found to be time-invariant, and thus can be directly implemented in the form of a full state feedback controller.Copyright © 2011 by General Motors
Emergent linguistic rules from inducing decision trees: disambiguating discourse clue words

We apply decision tree induction to the problem of discourse clue word sense disambiguation. The automatic partitioning of the training set which is intrinsic to decision tree induction gives rise to linguistically viable rules.
Stable pushing: mechanics, controllability, and planning

We would like to give robots the ability to position and orient parts in the plane by pushing, particularly when the parts are too large or heavy to be grasped and lifted. Unfortunately, the motion of a pushed object is generally unpredictable due to unknown support friction forces. With multiple pushing contact points, however, it is possible to find pushing directions that cause the object to remain fixed to the manipulator. These are called stable pushing directions. In this article we consider the problem of planning pushing paths using stable pushes. Pushing imposes a set of nonholonomic velocity constraints on the motion of the object, and we study the issues of local and global controllability during pushing with point contact or stable line contact. We describe a planner for finding stable pushing paths among obstacles, and the planner is demon strated on several manipulation tasks.
Foreign Know-How, Firm Control, and the Income of Developing Countries

NBER WORKING PAPER SERIESFOREIGN KNOW-HOW, FIRM CONTROL, AND THE INCOME OF DEVELOPINGCOUNTRIESAriel BursteinAlexander Monge-NaranjoWorking Paper 13073http://www.nber.org/papers/w13073NATIONAL BUREAU OF ECONOMIC RESEARCH1050 Massachusetts AvenueCambridge, MA 02138May 2007We thank Manuel Amador, Pol Antras, Andy Atkeson, Wilbur John Coleman, Pete Klenow, Eva Nagypal,Giorgio Primiceri, Andres Rodriguez-Clare, Esteban Rossi-Hansberg, Martin Schneider, Aleh Tsyvinski,and seminar participants in various places for useful comments and suggestions. Gilberto Arce providedsuperb research assistance. The views expressed herein are those of the author(s) and do not necessarilyreflect the views of the National Bureau of Economic Research.© 2007 by Ariel Burstein and Alexander Monge-Naranjo. All rights reserved. Short sections of text,not to exceed two paragraphs, may be quoted without explicit permission provided that full credit,including © notice, is given to the source.
Extending the scope of the Checkpoint‐on‐Failure protocol for forward recovery in standard MPI

SUMMARY Most predictions of exascale machines picture billion ways parallelism, encompassing not only millions of cores but also tens of thousands of nodes. Even considering extremely optimistic advances in hardware reliability, probabilistic amplification entails that failures will be unavoidable. Consequently, software fault tolerance is paramount to maintain future scientific productivity. Two major problems hinder ubiquitous adoption of fault tolerance techniques: (i) traditional checkpoint-based approaches incur a steep overhead on failure free operations and (ii) the dominant programming paradigm for parallel applications (the message passing interface (MPI) Standard) offers extremely limited support of software-level fault tolerance approaches. In this paper, we present an approach that relies exclusively on the features of a high quality implementation, as defined by the current MPI Standard, to enable advanced forward recovery techniques, without incurring the overhead of customary periodic checkpointing. With our approach, when failure strikes, applications regain control to make a checkpoint before quitting execution. This checkpoint is in reaction to the failure occurrence rather than periodic. This checkpoint is reloaded in a new MPI application, which restores a sane environment for the forward, application-based recovery technique to repair the failure-damaged dataset. The validity and performance of this approach are evaluated on large-scale systems, using the QR factorization as an example. Published 2013. This article is a US Government work and is in the public domain in the USA.
The Effect of Providing Peer Information on Retirement Savings Decisions

Using a field experiment in a 401(k) plan, we measure the effect of disseminating information about peer behavior on savings. Low-saving employees received simplified plan enrollment or contribution increase forms. A randomized subset of forms stated the fraction of age-matched coworkers participating in the plan or age-matched participants contributing at least 6% of pay to the plan. We document an oppositional reaction: the presence of peer information decreased the savings of nonparticipants who were ineligible for 401(k) automatic enrollment, and higher observed peer savings rates also decreased savings. Discouragement from upward social comparisons seems to drive this reaction.
Negative Link Prediction in Social Media

Signed network analysis has attracted increasing attention in recent years. This is in part because research on signed network analysis suggests that negative links have added value in the analytical process. A major impediment in their effective use is that most social media sites do not enable users to specify them explicitly. In other words, a gap exists between the importance of negative links and their availability in real data sets. Therefore, it is natural to explore whether one can predict negative links automatically from the commonly available social network data. In this paper, we investigate the novel problem of negative link prediction with only positive links and content-centric interactions in social media. We make a number of important observations about negative links, and propose a principled framework NeLP, which can exploit positive links and content-centric interactions to predict negative links. Our experimental results on real-world social networks demonstrate that the proposed NeLP framework can accurately predict negative links with positive links and content-centric interactions. Our detailed experiments also illustrate the relative importance of various factors to the effectiveness of the proposed framework.
Formula-Derived versus Observed Market Prices: An Application for Segregated Early Weaned Pigs

A formula (the "K-State formula") for deriving the price of segregated early weaned (SEW) pigs using corn, soybean meal, and market hog prices was estimated based on equating return on investment for the different phases of swine production farrow, nursery, and finish. USDA reported SEW pig prices were compared with prices derived from the K-State formula and several other common formulas. Based on root mean squared error and mean absolute error accuracy measures, the K-State formula did a better job of predicting spot-market prices than the other formulas. In terms of the K-State formula accurately predicting spot market prices, producers appear to form price expectations based on futures plus expected basis more so than simply futures prices or current cash prices. However, the manner in which the formula is used (i.e., method of choosing price expectations) will depend on the risk attitudes of the buyer and seller as well as the nature of their business relationship. Developing pricing formulas based on the framework outlined here (equal returns on investment) has merit for establishing prices in the absence of publicly reported information, however, it is important that users of the formula understand the conceptual framework of how and why it was developed.
Dimeric pyrrole–imidazole alkaloids: synthetic approaches and biosynthetic hypotheses

The pyrrole–imidazole alkaloids are a group of structurally unique and biologically interesting marine sponge metabolites. Among them, the cyclic dimers have caught synthetic chemists' attention particularly. Numerous synthetic strategies have been developed and various biosynthetic hypotheses have been proposed for these fascinating natural products. We discuss herein the synthetic approaches and the biosynthetic insights obtained from these studies.
CONGESTION TOLLING AND URBAN SPATIAL STRUCTURE

Congestion tolling results in a more concentrated city, according to the standard model of urban traffic congestion and urban spatial structure. Recently, a new bottleneck model of rush-hour urban auto congestion has been developed incorporating trip-timing decisions. In the simplest bottleneck model optimal congestion tolling without toll-revenue redistribution has no effect on trip price because the efficiency gains exactly match the toll revenue collected. Optimal congestion telling, then, has no effect on urban spatial structure. This research formalizes and further extends this result.