cssi/SciSciGPT-SciSciNet huggingface dataset:
Tax incentives and family labor supply in Austria

The family policy reform 2009 introduced tax deductibles for children and child care expenditures in Austria. In this paper we evaluate this reform based on a structural labor supply model with unitary households which has been estimated on the European Statistics on Income and Living Conditions cross-sections 2004–2008. We find that the reform had only small employment effects, most of them being generated through the introduction of a child care deductible. However, to illustrate the employment potential of a shift from universal child transfers to tax deductibles we propose additional simulations showing that such a policy shift would yield an increase in full time equivalents of approximately .70 % of overall employment, with married females increasing their labor supply by up to 1.5 %. While the proposed policy shifts have regressive effects in terms of their distributional impact, we show that phasing-out the tax deductible at higher income allows for the compensation of lower-income households without jeopardizing positive employment effects.
Reparametrization invariant collinear operators

In constructing collinear operators, which describe the production of energetic jets or energetic hadrons, important constraints are provided by reparametrization invariance (RPI). RPI encodes Lorentz invariance in a power expansion about a collinear direction, and connects the Wilson coefficients of operators at different orders in this expansion to all orders in ${\ensuremath{\alpha}}_{s}$. We construct reparametrization invariant collinear objects. The expansion of operators built from these objects provides an efficient way of deriving RPI relations and finding a minimal basis of operators, particularly when one has an observable with multiple collinear directions and/or soft particles. Complete basis of operators is constructed for pure glue currents at twist-4, and for operators with multiple collinear directions, including those appearing in ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}3$ jets, and for $pp\ensuremath{\rightarrow}2$ jets initiated via gluon fusion.
CHARGED SPIN-1/2 PARTICLE IN AN ARBITRARY MAGNETIC FIELD IN TWO SPATIAL DIMENSIONS: A SUPERSYMMETRIC QUANTUM MECHANICAL SYSTEM

It is shown that the 2×2 matrix Hamiltonian describing the dynamics of a charged spin-1/2 particle with g-factor 2 moving in an arbitrary, spatially dependent, magnetic field in two spatial dimensions can be written as the anticommutator of a nilpotent operator and its Hermitian conjugate. Consequently, the Hamiltonians for the two different spin projections form partners of a supersymmetric quantum mechanical system. The resulting supersymmetry algebra can then be exploited to explicitly construct the exact zero energy ground state wave function for the system. Modulo this ground state, the remainder of the eigenstates and eigenvalues of the two partner Hamiltonians form positive energy degenerate pairs. We also construct the spatially asymptotic form of the magnetic field which produces a finite magnetic flux and associated zero energy normalizable ground state wave function.
Finitely Precise Dynamic Programming and Portfolio Choice

Using a standard lifetime savings and portfolio choice model with a probabilistic choice function, we demonstrate that the predictions of the infinitely precise model are not robust to the introduction of realistic levels of household imprecision. The predicted deviations from the optimal stock/bond allocation are large and biased towards bonds, which can help explain the equity-premium puzzle.
Complex Interpolation of Hardy‐Type Subspaces

We consider the problem of complex interpolation of certain Hardy-type subspaces of Kothe function spaces. For example, suppose that X0 and X1 arc Kothe function spaces on the unit circle T. and let HX0 and HX1 be the corresponding Hardy spaces. Under mild conditions on X0. X1 we give a necessary and sufficient condition for the complex interpolation space [HX0. HX1]0 to coincide with HX0 where HX0 = [H0. H1]0. We develop a very general framework for such results and our methods apply to many more general situations including the vector–valued case.
Does quasi-long-range order in the two-dimensional XY model really survive weak random phase fluctuations?

Abstract Effective theories for random critical points are usually non-unitary, and thus may contain relevant operators with negative scaling dimensions. To study the consequences of the existence of negative-dimensional operators, we consider the random-bond XY model. It has been argued that the XY model on a square lattice, when weakly perturbed by random phases, has a quasi-long-range ordered phase (the random spin wave phase) at sufficiently low temperatures. We show that infinitely many relevant perturbations to the proposed critical action for the random spin wave phase were omitted in all previous treatments. The physical origin of these perturbations is intimately related to the existence of broadly distributed correlation functions. We find that those relevant perturbations do enter the Renormalization Group equations, and affect critical behavior. This raises the possibility that the random XY model has no quasi-long-range ordered phase and no Kosterlitz-Thouless (KT) phase transition.
Kinetics of the Oxidation of Trichloroethylene in Air via Heterogeneous Photocatalysis

Abstract Trichloroethylene in solution with air is oxidized rapidly in the presence of irradiated titanium dioxide. Dichloroacetyl chloride (DCAC), which is formed as an intermediate during the trichloroethylene reaction, also undergoes photocatalytic oxidation. This paper describes the kinetics of these reactions and how operating conditions influence the observed reaction rates. Annular photocatalytic reactors with thin films of titanium dioxide catalyst were used to make kinetic measurements. Observations of the reaction rate of trichloroethylene were made while varying parameters such as catalyst loading, feed flow rate, feed composition, and ultraviolet light energy. The observed reaction rates are higher by several orders of magnitude than those previously reported in the literature, and an expression for the prediction of rate as a function of reactant partial pressure is provided. The rate of reaction of the DCAC intermediate is also discussed. Air is shown to be an optimum oxidant, and an optimum humidity is established. The reaction is shown to proceed indefinitely under dry conditions, supporting the existence of a chlorine radical propagated surface reaction.
Inverting onto functions

We look at the hypothesis that all honest onto polynomial-time computable functions have a polynomial-time computable inverse. We show this hypothesis equivalent to several other complexity conjectures including: • In polynomial time, one can find accepting paths of nondeterministic polynomial-time Turing machines that accept Σ*. • Every total multivalued nondeterministic function has a polynomial-time computable refinement. • In polynomial time, one can compute satisfying assignments for any polynomial-time computable set of satisfiable formulae. • In polynomial time, one can convert the accepting computations of any nondeterministic Turing machine that accepts SAT to satisfying assignments.We compare these hypotheses with several other important complexity statements. We also examine the complexity of these statements where we only require a single bit instead of the entire inverse.
Energy bands in ordered beta‐brass

The energy bands in ordered beta-brass are calculated with a new choice of potential, one with a sounder theoretical basis than those of previous calculations. The position of the copper 3d bands is in much better agreement with optical reflectance data, thus giving us considerable confidence in the calculation techniques.
Compressive sensing over graphs

In this paper, motivated by network inference and tomography applications, we study the problem of compressive sensing for sparse signal vectors over graphs. In particular, we are interested in recovering sparse vectors representing the properties of the edges from a graph. Unlike existing compressive sensing results, the collective additive measurements we are allowed to take must follow connected paths over the underlying graph. For a sufficiently connected graph with n nodes, it is shown that, using O(k log(n)) path measurements, we are able to recover any k-sparse link vector (with no more than k nonzero elements), even though the measurements have to follow the graph path constraints. We mainly show that the computationally efficient l 1 minimization can provide theoretical guarantees for inferring such k-sparse vectors with O(k log(n)) path measurements from the graph.
Programming the war against water pollution

In every communications medium, today, including newspapers and magazines, television and radio, and even in personal conversations, we are constantly alerted to the problems of pollution. More often than not, we are asked to do something about these problems. Most of us are learning of little things we can do individually, in our personal lives, to help reduce pollution.
A Brief Comment on Instanton-like Singularities and Cosmological Horizons

We argue that in the presence of instanton-like singularities, the existence of cosmological horizons can become frame-dependent, i.e. a horizon which appears in Einstein frame may not appear in string frame. We speculate on the relation between instanton-like singularities and the formulation of quantum gravity in de Sitter space.
Application of the 915 MHz profiler for diagnosing and classifying tropical precipitating cloud systems

The NOAA Aeronomy Laboratory has developed a 915 MHz lower tropospheric wind profiler designed primarily for measuring wind in the planetary boundary layer of the tropics. In recent years the profiler has been used in many field programs worldwide. The profiler is being deployed by the Aeronomy Laboratory at several locations in the tropics to provide long-term measurements for the Tropical Ocean Global Atmosphere (TOGA) program and the Global Ocean Atmosphere Land Surface (GOALS) program. In the absence of precipitating cloud systems the profiler observes winds routinely up to altitudes of 3 to 6 km in the tropics depending primarily on humidity. In the presence of precipitating cloud systems, however, the profiler height coverage is substantially increased due to the presence of hydrometeors to which the profiler is sensitive at its wavelength of 33 cm. In this paper we examine the application of the 915 MHz profiler to the diagnosis and classification of precipitating cloud systems in the tropics. Preliminary results from Christmas Island confirm that at least half of tropical rainfall is stratiform in nature being associated with mesoscale convective systems. The 915 MHz profiler provides a means for the development of a climatology of tropical precipitating cloud systems. Such a climatology is needed to specify diabatic heating rates in large-scale numerical weather prediction and climate models. It should also help develop improved rain retrieval algorithms from satellite observations.
The WTO Dispute Settlement System: The First Ten Years

This paper reviews the operation of the WTO's dispute settlement system during its first ten years -- from 1995 to 2004. After a brief overview of the system, the experience of several major users of the system -- the United States, the European Communities, Canada, Japan, Brazil and India -- is examined and an evaluation is made in terms of how they have fared in advancing their major trade policy concerns on a subject matter and a country-by-country basis. Particular attention is paid to certain bilateral relationships, such as that of the United States and the EC. The paper then evaluates the system's success in settling disputes, in terms of whether disputes have been settled promptly, either through mutually agreed solutions or through implementation of panel/Appellate Body reports. The paper concludes that since its inception in 1995, the system has worked reasonably well in providing a reasonably effective mechanism through which WTO Members are able to resolve disputes, both at the consultation stage and following completion of formal dispute settlement proceedings. The system has not, however, achieved its goal of promptness in many cases. Copyright 2005, Oxford University Press.
The Separation of Mercury into Isotopes

EARLY in 1920 Harkins and Broeker reported a separation of chlorine into isotopes, which amounted at that time to an increase in density equal to 1550 parts per million. About six months later Bronsted and von Hevesy reported a separation of mercury, which was, however, only about one-thirtieth as great, or 50 parts per million. On account of the slightness of the density change reported for mercury, the evidence, that it had been separated did not appear to be conclusive, so it seemed worth while to attempt a confirmation by the same method—that is, a vaporisation at low pressures. As a result of 4 cuts of 2 on the heavy fraction or residue the density has been increased by 69 parts per million, and by the same number of cuts on the light fraction it has been decreased 62 parts, or the total density change obtained is 133 parts pet million, or 0.027 units of atomic weight.
Is Volatility Risk for the British Pound Priced in U.S. Options Markets

This paper estimates the premium for volatility risk for European currency options written on British pounds. The average annualized premium for volatility risk is neither statistically different from zero nor invariant to the option's moneyness. However, the risk premium is positively and nonproportionaly related to the level of volatility, except for out-of-the-money options. Finding a zero premium for volatility risk does not undermine the assumption of a zero-price volatility risk in many extant stochastic-volatility option pricing models and the option pricing formulas in those models.
A Madden-Julian Oscillation in tropospheric ozone

This is the first study to indicate a Madden-Julian Oscillation (MJO) in tropospheric ozone. Tropospheric ozone is derived using differential measurements of total column ozone and stratospheric column ozone measured from total ozone mapping spectrometer (TOMS) and microwave limb sounder (MLS) instruments. Two broad regions of significant MJO signal are identified in the tropics, one in the western Pacific and the other in the eastern Pacific. Over both regions, MJO variations in tropospheric ozone represent 5-10 Dobson Unit (DU) peak-to-peak anomalies. These variations are significant compared to mean background amounts of 20 DU or less over most of the tropical Pacific. MJO signals of this magnitude would need to be considered when investigating and interpreting particular pollution events since ozone is a precursor of the hydroxyl (OH) radical, the main oxidizing agent of pollutants in the lower atmosphere.
Marriage markets and divorce laws

This paper develops a model of search and learning in marriage markets to analyze how a liberalization of divorce laws affects marriage market outcomes. In particular we analyze how the move from mutual consent divorce to unilateral divorce affects marriage rates, the composition of those who marry, and divorce rates, under the assumption that households cannot reach Coasean bargains. The analysis highlights the distinction between the effects on the existing stock of married couples (a pipeline effect) and the effects on newly married couples (a selection effect). Although unilateral divorce laws increase divorce rates for those already married at the time of the law change, the change to unilateral divorce can cause those married to be better matched than those previously married under mutual consent divorce laws. Hence a change to unilateral divorce can cause a fall in the steady-state divorce rate. The results help interpret and reconcile much of the current empirical literature in this field.
Knot Floer filtration classes of topologically slice knots

The knot Floer complex and the concordance invariant e can be used to define a filtration on the smooth concordance group. We exhibit an ordered subset of this filtration that is isomorphic to ℕ × ℕ and consists of topologically slice knots.
Small cells in cervical-vaginal smears of patients treated with tamoxifen.

BACKGROUND “Small cells” have been described in the cervical-vaginal (Papanicolaou [Pap]) smears of patients receiving tamoxifen. The current study determined the frequency of this finding and its implications for the differential diagnosis. METHODS A computer-based search of the cytopathology files from January 1994 to December 1998 was performed for Pap smears from patients with a history of tamoxifen treatment. All smears were reviewed for the presence of “small cells” and endometrial cells. Pap smears from an age-matched control group that was not treated with tamoxifen also were screened for “small cells.” RESULTS Five hundred forty-eight Pap smears were identified from 425 patients (mean age, 62 years; average duration of treatment, 43 months). Clusters of these “small cells” were present in 104 Pap smears from 86 patients (19%). The background pattern was proliferative in the majority of the Pap smears (83%). In five Pap smears (5%), these “small cells” were interpreted originally as endometrial cells. In the remaining Pap smears, no reference to the presence of the cells was made in the original report. “Small cells” were identified in 79 Pap smears (18%) in the control group (n = 443 smears). CONCLUSIONS The incidence of “small cells” is similar in the Pap smears of patients with or without a history of tamoxifen treatment. These cells are similar to reserve cells noted in atrophic smears. However, as a result of the proliferative effect of tamoxifen in the cervical epithelium, these cells are prominent when admixed with superficial and intermediate cells in patients treated with tamoxifen. These cells need to be differentiated from endometrial cells to avoid unnecessary follow-up procedures. Cancer (Cancer Cytopathol) 2001;93:23–28. © 2001 American Cancer Society.
Acetals and ketals of 2-(2-pyridyl)propane-1,3-diol novel protection for carbonyl groups

Abstract Aldehydes and ketones are readily converted into the corresponding 1,3-dioxanes by treatment with 2-(2-pyridyl)propane-1,3-diol. The protective group is easily removed under mild base conditions after activation by quaternization with methyl iodide.
Dynamic Analysis of Hybrid Serial Manipulator Systems Containing Parallel Modules

Analyse dynamique d'un manipulateur hybride comportant a la fois des elements en serie et des modules a structure parallele
Mathematical model for a spirally-wound lithium-ion cell

Abstract A new computational method is proposed that can be used to reduce the numerical difficulties in modeling the electrical and thermal behavior of a spirally wound Li-ion cell. By analyzing the winding locus of the electrodes, some important geometric relationships of the spiral surfaces are identified, and algorithms for coordinate transform and variable extrusion between 2-D and 3-D domains are derived. Our method reduces the computation time and memory requirements needed to simulate the cell performance. The accuracy of our method was validated by model-to-model comparisons.
FARADAY ROTATION DISTRIBUTIONS FROM STELLAR MAGNETISM IN WIND-BLOWN BUBBLES

Faraday rotation is a valuable tool for detecting magnetic fields. Here, the technique is considered in relation to wind-blown bubbles. In the context of spherical winds with azimuthal or split monopole stellar magnetic field geometries, we derive maps of the distribution of position angle (P.A.) rotation of linearly polarized radiation across projected bubbles. We show that the morphology of maps for split monopole fields are distinct from those produced by the toroidal field topology; however, the toroidal case is the one most likely to be detectable because of its slower decline in field strength with distance from the star. We also consider the important case of a bubble with a spherical sub-volume that is field-free to approximate crudely a swept-up wind interaction between a fast wind (or possibly a supernova ejecta shell) overtaking a slower magnetized wind from a prior state of stellar evolution. With an azimuthal field, the resultant P.A. map displays two arc-like features of opposite rotation measure, similar to observations of the supernova remnant G296.5+10.0. We illustrate how P.A. maps can be used to disentangle Faraday rotation contributions made by the interstellar medium versus the bubble. Although our models involve simplifying assumptions, their consideration leads to a number of general robust conclusions for use in the analysis of radio mapping data sets.
On the topological size of p-m-complete degrees

Abstract All polynomial many-one degrees are shown to be of second Baire category in the superset topology when witness functions are allowed to run in 2loghn time, for any h. Any improvement of this result for the complete p-m-degrees of RE, EXP or NP implies P ≠ NP or the nonisomorphism of the NP-complete sets.
On the complexity of computations under varying sets of primitives

The goal of the current research is the study of lower bounds on the complexity of a set of searching problems under various restrictions on the nature of the primitive operation used to determine each branch in a search tree. The model, first studied by Rabin [6], Reingold [7], and Spira [9] and to be described in more detail in the next section, has programs consisting of two types of statements. Query statements are of the form
Shape Optimization of Elastic Hollow Bars

In this paper a unified shape optimum design scheme, combining the material derivative and boundary parametrization is presented to find the optimal cross-sectional shapes of elastic hollow bars. Performance criteria can be the bending stiffness, the torsional rigidity, or the weight of the bar. The existence of a keyway (an example of geometric irregularity) can be considered as well. Material property can be either isotropic or anisotropic. Various numerical examples have been provided to show the validity of the presented approach.
CONTINUOUS TRACE C ∗ -ALGEBRAS, GAUGE GROUPS AND RATIONALIZATION

Let ζ be an n-dimensional complex matrix bundle over a compact metric space X and let Aζ denote the C*-algebra of sections of this bundle. We determine the rational homotopy type as an H-space of UAζ, the group of unitaries of Aζ. The answer turns out to be independent of the bundle ζ and depends only upon n and the rational cohomology of X. We prove analogous results for the gauge group and the projective gauge group of a principal bundle over a compact metric space X.
9-CF3 and 13-CF3–β-carotene, canthaxanthin and related carotenoids. Synthesis, characterization and electrochemical data

Abstract The preparation and characterization of the following trifluoromethylated carotenoids are reported: 9-CF3–, 13-CF3–, 9,9′-bis-CF3–, 13,13′-bis-CF3–β-carotene, 9-CF3– and 13-CF3–canthaxanthin, 13′-CF3– and, 9′-CF3–4-oxo-β-carotene, 13′-CF3–adonirubin and 3-dehydro-13′-CF3–canthaxanthin. The CF3 group exhibits a strong cis-directing effect leading primarily to the cis isomer (near the CF3 group, i.e., all-E) in the synthetic mixtures. The minor all-trans isomer could be enriched by sensitized irradiation; however, they were found to be only marginally stable at room temperature. The CF3 group also exhibits a stabilizing effect towards oxidation reactions. Spectral data and oxidation potentials of these fluorinated carotenoids are reported.
Is a color superconductor topological

A fully gapped state of matter, whether insulator or superconductor, can be asked if it is topologically trivial or nontrivial. Here we investigate topological properties of superconducting Dirac fermions in 3D having a color superconductor as an application. In the chiral limit, when the pairing gap is parity even, the right-handed and left-handed sectors of the free space Hamiltonian have nontrivial topological charges with opposite signs. Accordingly, a vortex line in the superconductor supports localized gapless right-handed and left-handed fermions with the dispersion relations $E=\ifmmode\pm\else\textpm\fi{}v{p}_{z}$ ($v$ is a parameter dependent velocity) and thus propagating in opposite directions along the vortex line. However, the presence of the fermion mass immediately opens up a mass gap for such localized fermions and the dispersion relations become $E=\ifmmode\pm\else\textpm\fi{}v\sqrt{{m}^{2}+{p}_{z}^{2}}$. When the pairing gap is parity odd, the situation is qualitatively different. The right-handed and left-handed sectors of the free space Hamiltonian in the chiral limit have nontrivial topological charges with the same sign and therefore the presence of the small fermion mass does not open up a mass gap for the fermions localized around the vortex line. When the fermion mass is increased further, there is a topological phase transition at $m=\sqrt{{\ensuremath{\mu}}^{2}+{\ensuremath{\Delta}}^{2}}$ and the localized gapless fermions disappear. We also elucidate the existence of gapless surface fermions localized at a boundary when two phases with different topological charges are connected. A part of our results is relevant to the color superconductivity of quarks.
Skip sequencing: A decision problem in questionnaire design

This paper studies questionnaire design as a formal decision problem, focusing on one element of the design process: skip sequencing. We propose that a survey planner use an explicit loss function to quantify the trade-off between cost and informativeness of the survey and aim to make a design choice that minimizes loss. We pose a choice between three options: ask all respondents about an item of interest, use skip sequencing, thereby asking the item only of respondents who give a certain answer to an opening question, or do not ask the item at all. The first option is most informative but also most costly. The use of skip sequencing reduces respondent burden and the cost of interviewing, but may spread data quality problems across survey items, thereby reducing informativeness. The last option has no cost but is completely uninformative about the item of interest. We show how the planner may choose among these three options in the presence of two inferential problems, item nonresponse and response error.
Positron Annihilations at the Galactic Center: Generating More Questions Than Answers

The bulge of our Galaxy is illuminated by the 0.511 MeV gamma-ray line flux from annihilations of nonrelativistic positrons. The emission is strongly concentrated at the Galactic Center (GC), in contrast to gamma-ray maps tracing nucleosynthesis (e.g., the 1.809 MeV line from decaying 26 Al) or cosmic ray processes (e.g., the 1–30 MeV continuum), which reveal a bright disk with a much less prominent central region. If positrons are generated at relativistic energies, higher-energy gamma rays will also be produced from inflight annihilation of positrons on ambient electrons. The comparison of the gamma-ray spectrum from inflight annihilation to the observed diffuse Galactic gamma-ray data constrains the injection energies of Galactic positrons to be less than 3 MeV.
Adaptive energy-efficient spectrum probing in cognitive radio networks

In cognitive radio networks, secondary users must constantly probe the spectrum to promptly detect the arrival and the departure of primary users (PUs). However, spectrum probing is an energy-consuming process. This indicates the tradeoff between the frequency of spectrum probing and the delay of detecting the PU state change, and highlights the need for energy-conscious spectrum-probing strategies. In this paper, we provide a theoretical framework to find the optimal spectrum-probing methods that minimize the probing delay under a constraint on energy consumption in real stochastic environments. Moreover, we design a practical, sub-optimal adaptive-probing strategy that self-learns the behavior of the PU's dynamics and exploits the proposed optimal probing method. Specifically, we find that the most widely used spectrum-probing scheme, i.e., periodic probing, is not optimal when the arrival rate of the PU state change is not constant or when the distribution of PU channel occupancy/vacancy is not uniform. On the other hand, the derived optimal and adaptive strategies can adapt to the dynamics of PUs and adjust the probing intervals based on the time-varying arrival rate of the PU state changes or the non-uniform distribution of PU channel occupancy/vacancy. Our simulation results show that the optimal spectrum-probing strategies and adaptive-probing methods perform much better and consume much less energy than periodic probing in realistic environments.
Pricing Currency Risk under Currency Boards

Currency risk is one of the two components of the total interest rate differential. Hard pegs, such as currency boards, are meant to reduce or even eliminate currency risk, thus reducing domestic interest rates. This paper investigates the patterns and determinants of the currency risk premium in two currency boards, Argentina and Hong Kong. Despite the presumed rigidity of currency boards, the currency premium is almost always positive and at times very large. Its term structure is usually upward sloping, but flattens out or even becomes inverted at times of turbulence. The premium and its term structure depend on domestic and global factors, related to devaluation expectations and risk perceptions.
Symmetry reduction of sh-Lie structures and of local functionals

Abstract Reduced sh-Lie structures have been studied for the case when a Lie group acts on the fibers of a vector bundle while preserving the base space of the bundle. In this paper we investigate how one obtains a reduced sh-Lie structure using the ideas of symmetry reduction where the action of the Lie group is transversal to the fibers of the bundle. We also show how local functionals are reduced using these ideas.
Grades, Gender, and Encouragement: A Regression Discontinuity Analysis.

The author employs a regression discontinuity design to provide direct evidence on the effects of grades earned in economics principles classes on the decision to major in economics and finds a differential effect for male and female students. Specifically, for female students, receiving an A for a final grade in the first economics class is associated with a meaningful increase in the probability of majoring in economics, even after controlling for the numerical grade earned in the class. This suggests that for female students, the feedback that is embedded in the course letter grade has an encouragement effect on their decision to study economics further. The author finds no evidence of a similar effect for male students.
A taxonomy of fairness and temporal logic problems for Petri nets

In this paper, we define a temporal logic for reasoning about Petri nets. We show the model checking problem for this logic to be PTIME equivalent to the Petri net reachability problem. Using this logic and two refinements, we show the fair nontermination problem to be PTIME equivalent to reachability for several definitions of fairness. For other versions of fairness, this problem is shown to be either PTIME equivalent to the boundedness problem or highly undecidable. In all, 24 versions of fairness are examined.
Reversible interconversion of a divalent vanadium bronze between δ and β quasi-1D structures.

Charge fluctuations along the quasi-1D frameworks of MxV2O5 bronzes have evinced much recent interest owing to the manifestation of colossal metal–insulator transitions and superconductivity. Depending upon the nature of the intercalating cation (M), distinctive geometries of the V2O5 framework are accessible. Herein, we demonstrate an unprecedented reversible transformation between double-layered (δ) and tunnel (β) quasi-1D geometries for nanowires of a divalent vanadium bronze, CaxV2O5 (x ≈ 0.23), upon annealing-induced dehydration and hydrothermally induced hydration. Such a facile hydration/dehydration-induced interconversion between two prominent quasi-1D structures (accompanied by a change in charge-ordering motifs) has not been observed in the bulk and is posited to result from the ease of propagation of crystallographic slip processes across the confined nanowire widths for the δ → β conversion and the facile diffusion of water molecules within the tunnel geometries for the β → δ reversion.
THE 24 MICRON VIEW OF EMBEDDED STAR FORMATION IN NGC 7129

We present observations of the star formation region NGC 7129 taken with the Multiband Imaging Photometer for Spitzer (MIPS). A significant population of sources, likely pre-main-sequence members of the young stellar cluster, are revealed outside the central photoionization region. Combining Infrared Array Camera (IRAC) and ground-based near-infrared images, we have obtained colors and spectral energy distributions for some 60 objects. The [3.6]-[4.5] versus [8]-[24] color-color plane shows sources clustered at several different loci, which roughly correspond to the archetypal evolutionary sequence Class 0, I, II, and III. We obtain preliminary classifications for 36 objects and find significant numbers of both Class I and II objects. Most of the pre-main-sequence candidates are associated with the densest part of the molecular cloud surrounding the photoionization region, indicating active star formation over a broad area outside the central cluster. We discuss three Class II candidates that exhibit evidence of inner disk clearing, which would be some of the youngest known examples of a transition from accretion to optically thin quiescent disks.
An Analysis of the Shapes of Ultraviolet Extinction Curves. IV. Extinction without Standards

In this paper we present a new method for deriving UV through IR extinction curves, based on the use of stellar atmosphere models to provide estimates of the intrinsic (i.e., unreddened) stellar spectral energy distributions (SEDs), rather than unreddened (or lightly reddened) standard stars. We show that this "extinction without standards" technique greatly increases the accuracy of the derived extinction curves and allows realistic estimations of the uncertainties. An additional benefit of the technique is that it simultaneously determines the fundamental properties of the reddened stars themselves, making the procedure valuable for both stellar and interstellar studies. Given the physical limitations of the models we currently employ, the technique is limited to main-sequence and mildly evolved B stars. However, in principle, it can be adapted to any class of star for which accurate model SEDs are available and for which the signatures of interstellar reddening can be distinguished from those of the stellar parameters. We demonstrate how the extinction without standards curves make it possible to (1) study the uniformity of curves in localized spatial regions with unprecedented precision, (2) determine the relationships between different aspects of curve morphology, (3) produce high-quality extinction curves from low color excess sight lines, and (4) derive reliable extinction curves for mid to late B stars, thereby increasing spatial coverage and allowing the study of extinction in open clusters and associations dominated by such stars. The application of this technique to the available database of UV through IR SEDs, and to future observations, will provide valuable constraints on the nature of interstellar grains and on the processes that modify them, and it will enhance our ability to remove the multiwavelength effects of extinction from astronomical energy distributions.
Spectral simulation of hybrid bodies with deformable and rigid materials

We presents a spectral approach to simulate hybrid objects with deformable and rigid materials in real time. This framework is able to handle large-scale model under the help of GPU's parallel computation.
A NOTE ON THE TIME EVOLUTION OF GENERALIZED COHERENT STATES

I consider the time evolution of generalized coherent states based on non-standard fiducial vectors, and show that only for a restricted class of such vectors does the associated classical motion determine the quantum evolution of the states. I discuss some consequences of this for path integral representations.
Semi-analytic estimates of Lyapunov exponents in lower-dimensional systems

Abstract Statistical arguments, seemingly well-justified in higher dimensions, can also be used to derive reasonable estimates of Lyapunov exponents χ in lower-dimensional Hamiltonian systems. This Letter explores the assumptions incorporated into these arguments. The predicted χ 's are insensitive to most details, but do depend sensitively on the nongeneric form of the auto-correlation function characterising the time-dependence of an orbit. This dependence on dynamics implies a fundamental limitation to the application of thermodynamic arguments to lower-dimensional systems.
Uncertainty analysis of diffuse-gray radiation enclosure problems

Uncertainty analysis methods, which are adapted from experimental techniques, are applied to diffuse-gray radiation enclosure problems. The propagation of uncertainties in view factors, emissivities, surface areas, and boundary conditions into the computed results is developed along with the required sensitivity analysis. Special considerations of view factor reciprocity and closure are discussed, and it is shown that strict enforcement of these constraints greatly reduces the sensitivity of the results to errors in view factors and surface areas. Illustrative examples are given. The uncertainty analysis gives strong insights into the practical fidelity of diffuse-gray enclosure computations. f, I i M N Nomenclature area of surface k vector of coefficients in equation (3) diagonal matrix of areas diagonal matrix with zeros for elements 1 to M diagonal matrix with ek for elements k = 1 to matrix of view factors matrix defined with equation (30) transpose of F element i j of F identity matrix vector of ones number of surfaces with specified heat flux total number of surfaces irradiation incident on surface k net heat flux on surface k radiosity leaving surface k vector of radiosities and ek for elements k = M + l to N M and zeros for elements M t1 to N ' Professor, member AIAA, * Assistant Professor, member AIAA Professor, Associate Fellow AIAA, Professor and Head, Copyiiglll 1993 by the American lilnliiule Of AcronauliCS and Astronaurics. 1°C. All rights rercrved. 1 r intermediate result vector temperature on surface k U,,) uncertainty in parameter (.) Greek 69, radiosity error vector t k U Stefan-Boltzmann constant emissivity on surface k
Trapped particle destabilization of the internal kink mode

The internal kink mode is destabilized by trapped high‐energy particles, leading to a new branch of the internal kink dispersion relation with a real frequency near the average trapped‐particle precession frequency and a growth rate of the same magnitude. This trapped particle branch of the dispersion relation is investigated numerically for a variety of particle distributions. Mode growth rate and frequency is found as a function of plasma β, density, and trapped‐particle energy and distribution. The high‐energy trapped particle sources considered are neutral beam injection, ion‐cyclotron heating, and fusion alpha particles. Relevance for various plasma heating schemes is discussed.
On global attractors of the 3D Navier-Stokes equations

Abstract In view of the possibility that the 3D Navier–Stokes equations (NSE) might not always have regular solutions, we introduce an abstract framework for studying the asymptotic behavior of multi-valued dissipative evolutionary systems with respect to two topologies—weak and strong. Each such system possesses a global attractor in the weak topology, but not necessarily in the strong. In case the latter exists and is weakly closed, it coincides with the weak global attractor. We give a sufficient condition for the existence of the strong global attractor, which is verified for the 3D NSE when all solutions on the weak global attractor are strongly continuous. We also introduce and study a two-parameter family of models for the Navier–Stokes equations, with similar properties and open problems. These models always possess weak global attractors, but on some of them every solution blows up (in a norm stronger than the standard energy one) in finite time.
Genericity and randomness over feasible probability measures

This paper investigates the notion of resource-bounded genericity developed by Ambos-Spies, Fleischhack, and Huwig. Ambos-Spies, Neis, and Terwijn have recently shown that every language that is t(n)-random over the uniform probability measure is t(n)-generic. It is shown here that, in fact, every language that is t(n)-random over any strongly positive, t(n)-computable probability measure is t(n)-generic. Roughly speaking, this implies that, when genericity is used to prove a resource-bounded measure result, the result is not specific to the underlying probability measure.
The Photolytic Disproportionation of Dialkyl 2,2-Di(Phenylseleno)propanedioates

Abstract Dialkyl-2,2-di(phenylseleno)propanedioates undergo disproportionation to form tetralkyl 1,1,2,2-ethylene tetracarboxylates and diphenyl diselenide upon photolysis. Evidence for the intermediacy of a capto-dative radical intermediate in this process is described.
Coupling of electrons to the electromagnetic field in a localized basis

A simple formula is obtained for coupling electrons in a complex system to the electromagnetic field. It includes the effect of intra-atomic excitations and nuclear motion, and can be applied in, e.g., first-principles-based simulations of the coupled dynamics of electrons and nuclei in materials and molecules responding to ultrashort laser pulses. Some additional aspects of nonadiabatic dynamical simulations are also discussed, including the potential of ``reduced Ehrenfest'' simulations for treating problems where standard Ehrenfest simulations will fail.
EXACT SOLUTION OF AN IRREVERSIBLE ONE-DIMENSIONAL MODEL WITH FULLY BIASED SPIN EXCHANGES

We introduce a model with conserved dynamics, where nearest neighbor pairs of spins ↑↓ (↓↑) can exchange to assume the configuration ↓↑ (↑↓), with rate β(α), through energy decreasing moves only. We report exact solution for the case when one of the rates, α or β, is zero. The irreversibility of such zero-temperature dynamics results in strong dependence on the initial conditions. Domain wall arguments suggest that for more general, finite-temperature models with steady states the dynamical critical exponent for the anisotropic spin exchange is different from the isotropic value.
Synthesis of non-natural glycosylamino acids containing tumor-associated carbohydrate antigens

Abstract The synthesis of biologically relevant glycosylamino acids using a non-natural amino acid as the glycosyl acceptor is described. The glycosylation reaction of a monosaccharide tri-chloroacetimidate donor with Fmoc- l -hydroxynorleucine benzyl ester provided the α-O-linked product. Conversely, when the glycosylation reaction was carried out with a glycal epoxide donor, the β-O-linked product predominated. We have used these two complementary glycosylation reactions to synthesize five different glycosylamino acids, each containing the Tn, TF, STn, Lewisy or Globo-H tumor-associated carbohydrate antigens.
Charge stripe in an antiferromagnet: 1d band of composite excitations

Abstract With the help of analytical and numerical studies of the t – J z model we argue that the charge stripe in an antiferromagnetic insulator should be understood as a system of holon–spin–polaron excitations condensed at the self-induced antiphase domain wall. The structure of such a charge excitation is studied in detail with numerical and analytical results for various quantities being in a very close agreement. An analytical picture of these excitations occupying an effective 1D stripe band is also in a very good accord with numerical data. The emerging concept advocates the primary role of the kinetic energy in favoring the stripe as a ground state. A comparative analysis suggests the effect of pairing and collective meandering on the energetics of the stripe formation to be secondary.
Morphology, stratigraphy, and surface roughness properties of Venusian lava flow fields

[1] Morphologic characteristics, flow stratigraphy, and radar backscatter properties of five lava flow fields on Venus (Turgmam Fluctus, Zipaltonal Fluctus, Tuli Mons/Uilata Fluctus, Var Mons, and Mylitta Fluctus) were examined to understand flow field emplacement mechanisms and relationships to other surface processes. These analyses indicate that the flow fields studied developed through emplacement of numerous, thin flow units, presumably over extended periods of time. Although the Venusian fields display flow morphologies similar to those observed within terrestrial flow fields, the Venusian flow units are significantly larger and have a larger range of radar backscatter coefficients. Both simple and compound flow emplacement appear to have occurred within the flow fields. A potential correlation between flow rheology and radar brightness is suggested by differences in planform morphology, apparent flow thickness, and apparent sensitivity to topography between bright and dark flows. Distributary flow morphologies may result from tube-fed flows, and postemplacement modification by processes such as flow inflation and crustal foundering is consistent with discrete zones of increased radar brightness within individual flow lobes. Mapping of these flow fields does not indicate any simple evolutionary trend in eruptive/resurfacing style within the flow fields, or any consistent temporal sequence relative to other tectonic and volcanic features.
Sound Symbolism, Onomatopoeia, and New Guinea Frog Names

Brent Berlin has recently proposed the use of r sounds as a substantive universal in the names given to frogs and toads, a tendency that he attributes to onomatopoeia. A data set from over 200 New Guinea languages is analyzed. Berlin's proposal regarding r sounds receives strong support, but an even more significant pattern is found with respect to g sounds. Onomatopoeia is a possible motivation for both of these pattern
Indirect searches for Z'-like resonances at the LHC

We explore the possibility of indirectly observing the effects of Z{prime}-like particles with electroweak strength couplings in the Drell-Yan channel at the LHC with masses above the resonance direct search reach. We find that, mostly due to statistical limitations, this is very unlikely in almost all classes of models independently of the spin of the resonance. Not unexpectedly, the one exception to this general result is the case of degenerate Kaluza-Klein (KK) excitations of the photon and Z that occur in some extra-dimensional models. In this special case, the strong destructive interference with the Standard Model (SM) exchanges below the resonance mass leads to a well-known significant suppression of the cross section and thus increased sensitivity to this particular new physics scenario.
Carbon-13 and Nitrogen-15 Spin-Lattice Relaxation (T1) and Nuclear Overhauser Enhancement (NOE) Measurements for Acetamide and N,N-Dimethylacetamide

Nitrogen-15 spin-lattice relaxation times (T_1's) and nuclear Overhauser enhancement (NOE) values are found to vary over a range of concentrations for acetamide. Our data indicate that intermolecular amide-amide hydrogen bonds are broken on dilution in water. Carbon-13 spin-lattice relaxation times and nuclear Overhauser enhancement measurements are given for acetamide and N,N-dimethylacetamide at 5.3 M. There is good agreement between experimental and calculated relaxation rates assuming rapid rotation of the α methyl group and slow rotation about the amide bond.