cssi/SciSciGPT-SciSciNet huggingface dataset:
Can the introduction of a minimum wage in FYR Macedonia decrease the gender wage gap

This paper relies on simple framework to understand the gender wage gap in Macedonia and then simulates how the gender wage gap would behave after the introduction of a minimum wage. First, it presents a new albeit simple decomposition of the wage gap into three factors: (i) a wage level factor, that measures the extent to which the gender gap is driven by differences in wage levels among low-skilled workers of opposite sex; (ii) an skills endowment factor, that quantifies the extent to which the gender wage gap is driven because the share of high-skilled workers differs by gender; and (iii) returns to education factor, that measures the extent to which the gender gap exists is driven by differences by gender in returns to education. Second, the paper presents simple set of simulations that indicate that the introduction of a minimum wage in Macedonia can contribute to decrease the gender wage gap by up to 23 percent. Nevertheless, in order to get a significant improvement in the wage gap a rather high minimum wage may required, which may contribute to reductions in employment.
Spatial Variability of Tourism Demand and Differences in Economic Impact in a Rural Economic Development Context

Statistically predicted future tourism demand is used to conduct an economic impact analysis in twelve tourism zones in the state of Arkansas. The analysis reveals spatial variability in employment, and output growth that will continue into the future. Tourism has the potential as an economic growth engine for the state, especially in economically disadvantaged regions with long-term benefits.
Patent Injunctions and the Problem of Uniformity Cost

In eBay v. MercExchange, the Supreme Court correctly rejected a one-size-fitsall approach to patent injunctions. However, the Court’s opinion does not fully recognize that the problem of uniformity in patent law is more general and that this problem cannot be solved through case-by-case analysis. This Essay provides a field guide for implementing eBay using functional analysis and insights from a uniformity-cost framework developed more fully in prior work. While there can be no general rule governing equitable relief in patent cases, the traditional four factor analysis for injunctive relief should lead the cases to cluster around certain patterns that often will have an industry-specific cast. This Essay identifies these patterns and summarizes the guideposts that courts and litigants should look for when conducting the traditional analysis in patent cases. CARROLL NEW TYPE.DOC 4/17/2007 11:06 AM 421 PATENT INJUNCTIONS AND THE PROBLEM OF UNIFORMITY COST
Nickel-cadmium Battery Cell Reversal from Resistive Network Effects

During the individual cell short-down procedures often used for storing or reconditioning nickel-cadmium (Ni-Cd) batteries, it is possible for significant reversal of the lowest capacity cells to occur. The reversal is caused by the finite resistance of the common current-carrying leads in the resistive network that is generally used during short-down. A model is developed to evaluate the extent of such a reversal in any specific battery, and the model is verified by means of data from the short-down of a f-cell, 3.5-Ah battery. Computer simulations of short-down on a variety of battery configurations indicate the desirability of controlling capacity imbalances arising from cell configuration and battery management, limiting variability in the short-down resistors, minimizing lead resistances, and optimizing lead configurations.
Simulation of complex shock reflections from wedges in inert and reactive gaseous mixtures

Our calculations of complex and double Mach reflection are in close agreement with measurements for shocks reflecting in air from wedges. Because of the accuracy and speed of FCT algorithms and the effectiveness of adaptive rezoning, the calculations are accurate and economical even when the Mach stem develops very slowly. All of the important features (location of surfaces of discontinuity, pressure loading on the wedge surface, density contours) are correctly predicted. The results do not depend sensitively on whether the L-T or FAST2D code is used. Of the advances discussed in Section 1, multidimensional flux limiting and the adaptive regridding technique seem to be the most efficacious for reflections in nonreactive media. We conclude that FCT algorithms reduce numerical diffusion dramatically, assuring qualitative improvements in accuracy. We believe that to achieve comparable accuracy and efficiency, other hydrocodes must employ similar nonlinear algorithms and rezoning techniques.
Lectures on Superconformal Quantum Mechanics and Multi-Black Hole Moduli Spaces

The problem of unifying quantum mechanics and gravity is one of the great unsolved problems in twentieth century physics. Progress has been slowed by our inability to carry out relevant physical experiments. Some progress has nevertheless been possible, largely throught the use of gedanken experiments.
Provisioning Green Energy for Base Stations in Heterogeneous Networks

Cellular networks are among the biggest energy hogs of communication networks, and their contributions to the global energy consumption rapidly increase due to the surge of data traffic. With the development of green energy technologies, base stations (BSs) can be powered by green energy to reduce on-grid energy consumption and subsequently reduce carbon footprints. However, equipping a BS with a green energy system incurs additional capital expenditure (CAPEX) that is determined by the size of the green energy generator, the battery capacity, and other installation expenses. In this paper, we introduce and investigate the green energy provisioning (GEP) problem, which aims to minimize the CAPEX of deploying green energy systems in BSs while satisfying the quality-of-service (QoS) requirements of cellular networks. The GEP problem is challenging because it involves optimization over multiple time slots and across multiple BSs. We decompose the GEP problem into the weighted energy minimization problem and the green energy system sizing problem and propose a GEP solution consisting of the provision-cost-aware traffic load balancing algorithm and the binary energy system sizing algorithm to solve the subproblems and subsequently solve the GEP problem. We validate the performance and the viability of the proposed GEP solution through extensive simulations, which also conform to our analytical results.
NON LUMINOUS GAS RADIATION: APPROXIMATE EMISSIVITY MODELS

The main sources of non-luminous gas radiation in furnaces are carbon dioxide and water vapor. Approximation of the standard emissivities of water vapor and of carbon dioxide by mixed gray-gas model is studied. The model developed for carbon dioxide standard emi s si vi ti es covers a range of temperature of 3DO-1BOOK and a partial-pressure-length product range of 0.01 to 10 m atm. A mixture of six gray gases was adequate to cover the whole range. For the water vapor thermal radiation two models were developed to approximate the standard water ~apor emissi~ities. In the first model water ~apor is approximated by a mixture of four gray-gases and can be used in the temperature range of 300-700K and the partial-pressure-length range of 0.01 to 2 m atm. The second model is a piece-wise one in which one gray gas is used to cover the pL range 0.5-2 m and a second gray gas covered the range of 0.05-0.5 m. The model may be used in the temperature range of 700-l500K and has an error range of -2.3 to 3.7~.
Astronomical Engineering: A Strategy For Modifying Planetary Orbits

The Sun's gradual brightening will seriously compromise the Earth'sbiosphere within ∼ 109 years. If Earth's orbit migrates outward,however, the biosphere could remain intact over the entiremain-sequence lifetime of the Sun. In this paper, we explore thefeasibility of engineering such a migration over a long timeperiod. The basic mechanism uses gravitational assists to (in effect)transfer orbital energy from Jupiter to the Earth, and therebyenlarges the orbital radius of Earth. This transfer is accomplishedby a suitable intermediate body, either a Kuiper Belt object or a mainbelt asteroid. The object first encounters Earth during an inward passon its initial highly elliptical orbit of large (∼ 300 AU)semimajor axis. The encounter transfers energy from the object to theEarth in standard gravity-assist fashion by passing close to theleading limb of the planet. The resulting outbound trajectory of theobject must cross the orbit of Jupiter; with proper timing, theoutbound object encounters Jupiter and picks up the energy it lost toEarth. With small corrections to the trajectory, or additionalplanetary encounters (e.g., with Saturn), the object can repeat thisprocess over many encounters. To maintain its present flux of solarenergy, the Earth must experience roughly one encounter every 6000years (for an object mass of 1022 g). We develop the details ofthis scheme and discuss its ramifications.
A Bayesian approach to learning causal networks

Whereas acausal Bayesian networks represent probabilistic independence, causal Bayesian networks represent causal relationships. In this paper, we examine Bayesian methods for learning both types of networks. Bayesian methods for learning acausal networks are fairly well developed. These methods often employ assumptions to facilitate the construction of priors, including the assumptions of parameter independence, parameter modularity, and likelihood equivalence. We show that although these assumptions also can be appropriate for learning causal networks, we need additional assumptions in order to learn causal networks. We introduce two sufficient assumptions, called mechanism independence and component independence. We show that these new assumptions, when combined with parameter independence, parameter modularity, and likelihood equivalence, allow us to apply methods for learning acausal networks to learn causal networks.
Explicit Approximations for Strictly Nonlinear Oscillators with Slowly Varying Parameters with Applications to Free‐Electron Lasers

The first part of this paper summarizes the mathematical modeling of free electron lasers (FEL), and the remainder concerns general perturbation methods for solving FEL and other strictly nonlinear oscillatory problems with slowly varying parameters and small perturbations. We review and compare the methods of Kuzmak-Luke and of near-identity averaging transformations. In order to implement the calculation of explicit solutions we develop two approximation schemes. The first involves use of finite Fourier series to present either the leading approximation of the solution or the transformation of the governing equations to a standard form appropriate for the method of averaging. In the second scheme we fit a cubic poly-nomial to the potential such that the leading approximation is expressible in terms of elliptic functions. The ideas are illustrated with a number of examples which are also solved numerically to assess the accuracy of the various approximations.
Optimal transfer between close near-circular orbits

A nonlinear analysis is carried out for the optimal transfer between close near-circular noncoplanar orbits with no limit on time. The degeneracy of the linear analyses of Marec and Edelbaum is, thereby, removed and with the aid of a generalized Jacobi test, it is established that the minimum-impulse transfer requires, at most, three impulses. A field of extremals is generated in an orbit element space starting with the initial state and anticipated adjoint variables and integrating these variables by using the optimal thrust control law that maximizes the variational Hamiltonian. The nonoptimality of any four-impulse strategy is determined numerically by observing the reflection of every extremal from either an envelope (conjugate point test) or a switching surface on or before the application of the fourth impulse. This test is carried out in Regions I, II, and III of Marec, as well as the special transition region of Breakwell near the boundary of Region III.
The Prospects for Mathematical Logic in the Twenty-First Century

The four authors present their speculations about the future developments of mathematical logic in the twenty-first century. The areas of recursion theory, proof theory and logic for computer science, model theory, and set theory are discussed independently.
On the transition of a non-equilibrium system to an equilibrium system

It is shown that the most important feature of Non-Equilibrium Thermodynamics is not the entropy production, but the organization of the currents in order to flow. This is also needed to obtain the maximum entropy in the equilibrium state, as is required by Equilibrium Thermodynamics. This article is supplemented with comments by Hong Qian and Yves Pomeau and a final reply by the author.
Weak-Star Convergence and a Polynomial Approximation Problem

Let E be an arbitrary subset of the unit circle T and let f be a function defined on E. When there exist polynomials P n which are uniformly bounded by a number M > 0 on T and converge (pointwise) to f at each point of E? We give a necessary and sufficient description of such functions.
Li2Sn(OH)6

Hydro­thermally prepared dilithium tin hexa­hydro­xide crystallizes in the monoclinic system (space group P21/n), with the Sn atom at a site with \overline 1 symmetry and all other atoms in general positions. The Sn coordination polyhedron is made up of six hydro­xide groups. The Li atom is tetrahedrally coordinated by oxy­gen, with the tetrahedra sharing two corners and one edge with the adjacent Sn octahedra. Hydro­gen bonds between the OH groups provide additional bonds in the framework.
Exploiting hybrid channel information for downlink multi-user MIMO scheduling

We investigate the downlinkmulti-user MIMO (MU-MIMO) scheduling problem in the presence of imperfect Channel State Information at the transmitter (CSIT) that comprises of coarse and current CSIT as well as finer but delayed CSIT. This scheduling problem is characterized by an intricate `exploitation - exploration tradeoff' between scheduling the users based on current CSIT for immediate gains, and scheduling them to obtain finer albeit delayed CSIT and potentially larger future gains. We solve this scheduling problem by formulating a frame based joint scheduling and feedback approach, where in each frame a policy is obtained as the solution to a Markov Decision Process.We prove that our proposed approach can be made arbitrarily close to the optimal and then demonstrate its significant gains over conventional MU-MIMO scheduling.
Wave‐driven mass loss in the last year of stellar evolution: setting the stage for the most luminous core‐collapse supernovae

During the late stages of stellar evolution in massive stars (C fusion and later), the fusion luminosity in the core of the star exceeds the star’s Eddington luminosity. This can drive vigorous convective motions which in turn excite internal gravity waves. The local wave energy flux excited by convection is itself well above Eddington during the last few years in the life of the star. We suggest that an interesting fraction of the energy in gravity waves can, in some cases, convert into sound waves as the gravity waves propagate (tunnel) towards the stellar surface. The subsequent dissipation of the sound waves can unbind up to several M� of the stellar envelope. This wave-driven mass loss can explain the existence of extremely large stellar mass-loss rates just prior to core collapse, which are inferred via circumstellar interaction in some core-collapse supernovae (e.g. SNe 2006gy and PTF 09uj, and even Type IIn supernovae more generally). An outstanding question is understanding what stellar parameters (mass, rotation, metallicity and age) are the most susceptible to wave-driven mass loss. This depends on the precise internal structure of massive stars and the power spectrum of internal gravity waves excited by stellar convection.
A Ramsey theorem for partial orders with linear extensions

Abstract We prove a Ramsey theorem for finite sets equipped with a partial order and a fixed number of linear orders extending the partial order. This is a common generalization of two recent Ramsey theorems due to Sokic. As a bonus, our proof gives new arguments for these two results.
A Coasian model of international production chains

International supply chains require the coordination of numerous activities across multiple countries and firms. This paper develops a theoretical model of supply chains in which the measure of tasks completed within a firm is determined by parameters that define transaction costs and the cost of coordinating more activities within the firm. The structural parameters that govern these costs explain variation in supply chain length as well as cross-country variation in gross-output-to-value-added ratios. The structural parameters are linked to comparative advantage along and across supply chains. The paper provides an analytical treatment of trade and welfare responses to trade cost change in a simple two-country model. To explore the model's implications in a richer setting, the model is calibrated to match key observables in East Asia, and the calibrated model is used to evaluate implications of changes in model parameters for trade, welfare, the length of supply chains, and countries' relative position within them.
The Racial Wage Gap: The Importance of Labor Force Attachment Differences across Black, Mexican, and White Men

Labor market attachment differs significantly across young black, Mexican, and white men. Although it has long been agreed that potential experience is a poor proxy for actual experience for women, many view it as an acceptable approximation for men. Using the NLSY, this paper documents the substantial difference between potential and actual experience for both black and Mexican men. We show that the fraction of the black/ white and Mexican/white wage gaps that are explained by differences in potential experience are quite different from the fraction of the racial wage gaps that are explained by actual (real) experience differences.
Improved Upper Bounds for Pairing Heaps

Pairing heaps are shown to have constant amortized time insert and zero amortized time meld, thus improving the previous O(log n) amortized time bound on these operations. It is also shown that pairing heaps have a distribution sensitive behavior whereby the cost to perform an extract-min on an element x is O(log min(n, k)) where k is the number of heap operations performed since x's insertion. Fredman has observed that pairing heaps can be used to merge sorted lists of varying sized optimally, within constant factors. Utilizing the distribution sensitive behavior of pairing heap, an alternative method the employs pairing heaps for optimal list merging is derived.
PAHs, they're everywhere!

A brief history of the observations and experiments which have led to the hypothesis that polycyclic aromatic hydrocarbons (PAHs) are widespread throughout the interstellar medium is presented. The PAH signature spectrum is associated with dense molecular clouds (reflection nebulae, HII regions), proto-planetary and planetary nebulae, M supergiants, and a nova. Since it is difficult to imagine a plausible mechanism to exclude PAHs from being distributed throughout the diffuse interstellar medium, it is concluded that they must be there as well, implying that they are among the carriers of the Diffuse Interstellar Bands (DIBs). The spectral evidence in support of this is reviewed. This is followed by a very short survey of studies on Solar System objects and extraterrestrial materials (including comet Halley, meteorites and interplanetary dust particles) which have been recently shown to contain PAHs.
Path Selection and Route Preference in Human Navigation: A Progress Report

Two critical characteristics of human wayfinding are destination choice and path selection. Traditionally, the path selection problem has been ignored or assumed to be the result of minimizing procedures such as selecting the shortest path, the quickest path or the least costly path. In this paper I draw on existing literature from cognitive mapping and cognitive distance, to define possible route selection criteria other than these traditional ones. Experiments with route selection on maps and in the field are then described and analyzed to determine which criteria appear to be used as the environment changes and as one increases the number of nodes along a path (i.e., as trip chaining replaces a simple Origin-Destination (O-D) pairing.
Photosynthetic model systems

This review highlights recent studies of synthetic, covalently linked multicomponent molecular devices which mimic aspects of photosynthetic electron transfer. After an introduction to the topic, some of the salient features of natural bacterial photosynthetic reaction centers are described. Elementary electron transfer theory is briefly discussed in order to provide a framework for the discussion which follows. Early work with covalently linked photosynthetic models is then mentioned, with references to recent reviews. The bulk of the discussion concerns current progress with various triad (three-part) molecules. Finally, some even more complex multicomponent molecules are examined. The discussion will endeavor to point out aspects of photoinitiated electron transfer which are unique to the multicomponent species, and some of the considerations important to the design, synthesis and photochemical study of such molecules.
The Empirical Saddlepoint Approximation for GMM Estimators

The empirical saddlepoint distribution provides an approximation to the sampling distributions for the GMM parameter estimates and the statistics that test the overidentifying restrictions. The empirical saddlepoint distribution permits asymmetry, non-normal tails, and multiple modes. If identification assumptions are satisfied, the empirical saddlepoint distribution converges to the familiar asymptotic normal distribution. In small sample Monte Carlo simulations, the empirical saddlepoint performs as well as, and often better than, the bootstrap. The formulas necessary to transform the GMM moment conditions to the estimation equations needed for the saddlepoint approximation are provided. Unlike the absolute errors associated with the asymptotic normal distributions and the bootstrap, the empirical saddlepoint has a relative error. The relative error leads to a more accurate approximation, particularly in the tails.
Soft Theorems from Effective Field Theory

The singular limits of massless gauge theory amplitudes are described by an effective theory, called soft-collinear effective theory (SCET), which has been applied most successfully to make all-orders predictions for observables in collider physics and weak decays. At tree-level, the emission of a soft gauge boson at subleading order in its energy is given by the Low-Burnett-Kroll theorem, with the angular momentum operator acting on a lower-point amplitude. For well separated particles at tree-level, we prove the Low-Burnett-Kroll theorem using matrix elements of subleading SCET Lagrangian and operator insertions which are individually gauge invariant. These contributions are uniquely determined by gauge invariance and the reparametrization invariance (RPI) symmetry of SCET. RPI in SCET is connected to the infinite-dimensional asymptotic symmetries of the S-matrix. The Low-Burnett-Kroll theorem is generically spoiled by on-shell corrections, including collinear loops and collinear emissions. We demonstrate this explicitly both at tree-level and at one-loop. The effective theory correctly describes these configurations, and we generalize the Low-Burnett-Kroll theorem into a new one-loop subleading soft theorem for amplitudes. Our analysis is presented in a manner that illustrates the wider utility of using effective theory techniques to understand the perturbative S-matrix.
Symmetric Groups and Expanders

We construct an explicit generating sets Fn and ˜ Fn of the alternating and the symmetric groups, which make the Cayley graphs C(Alt(n), Fn) and C(Sym(n), ˜ Fn) a family of bounded degree expanders for all sufficiently large n. These expanders have many applications in the theory of random walks on groups and other areas of mathematics. A finite graph is called an ǫ-expander for some ǫ ∈ (0,1), if for any subset A ⊆ of size at most | |/2 we have |∂(A)| > ǫ|A| (where ∂(A) is the set of vertices of \A of edge distance 1 to A). The largest such ǫ is called the expanding constant of . Constructing families of ǫ-expanders with bounded valency is an important practical problem in computer science, because such graphs have many nice properties — for example they have a logarithmic diameter. For an excellent introduction to the subject we refer the reader to the book [14] by A. Lubotzky. Using counting arguments it can be shown that almost any 5 regular graph is 1/5-expander. However constructing an explicit examples of families expander graphs is a difficult problem. The first explicit construction of a family of expanders was done by G. Margulis in [19], using Kazhdan property T of SL3(Z). Currently there are several different construction of expanders. With the exception of a few recent ones based on the zig-zag products of graphs (see [2, 23, 24]), all constructions are based groups theory and use some variant of property T (property τ, Selberg property etc.). Kazhdan Property T is not very interesting for a given finite group G (all finite groups have property T), but the related Kazhdan constant with respect to some generating F set is. Given an infinite collection of finite groups Gi, it is a challenge to prove the existence of uniform Kazhdan constants with respect to properly chosen generating sets. This problem is related to construction a family of expanders using the Cayley graphs of the groups Gi. The original definition of property T uses the Fell topology of the unitary dual, see [11]. Here we will use an equivalent definition (only for discrete groups) which also addresses the notion of the Kazhdan constants.
Stimulation of osteoblast differentiation with guided ultrasound waves

Ultrasound induces mechanical vibration and heat, causing differentiation and proliferation in osteoblasts. All known in vitro evaluations of ultrasound are, however, performed with longitudinal ultrasound waves. We addressed a question: Do other forms of ultrasound waves, such as guided waves (longitudinal and guided flexural) transduced at a remote location, enhance differentiation of osteoblast cells? In this study, we employed guided Lamb waves that were induced in a borosilicate glass slide (cortical bone mimic). An average energy of 10–30 mW/cm2 for 20 min per day was applied to MC3T3 osteoblast-like cells, which were placed 30–75 mm distant from the transducer. The result revealed that guided waves significantly stimulated the differentiation and mineralization of MC3T3 cells. In particular, guided waves elevated mRNA expression levels of bone formation-related genes such as alkaline phosphatase, osteopontin, osteocalcin, osteoprotegerin, and bone sialoprotein on days 8 and 16. In addition, the amount of mineralization found via Alizarin red staining was increased by 157 % (p = 0.034). The amount of mineralization was found to be independent of distance from the transducer (p = 0.967). We demonstrate herein that ultrasound in a form of guided Lamb waves is capable of inducing osteoblast differentiation in vitro, and it may enable the stimulation of osteoblasts in vivo over a distance from the site of ultrasound application.
Flexible and Extensible Digital Object and Repository Architecture (FEDORA)

We describe a digital object and respository architecture for storing and disseminating digital library content. The key features of the architecture are: (1) support for heterogeneous data types; (2) accommodation of new types as they emerge; (3) aggregation of mixed, possibly distributed, data into complex objects; (4) the ability to specify multiple content disseminations of these objects; and (5) the ability to associate rights management schemes with these disseminations. This architecture is being implemented in the context of a broader research project to develop next-generation service modules for a layered digital library architecture.
Gender, Time Use, and Poverty in Sub-Saharan Africa

The papers in this volume examine the links between gender, time use, and poverty in Sub-Saharan Africa. They contribute to a broader definition of poverty to include time poverty, and to a broader definition of work to include household work. The papers present a conceptual framework linking both market and household work, review some of the available literature and surveys on time use in Africa, and use tools and approaches drawn from analysis of consumption-based poverty to develop the concept of a time poverty line and to examine linkages between time poverty, consumption poverty, and other dimensions of development in Africa such as education and child labor.
Navier-Stokes equations for generalized thermostatistics

Tsallis has proposed a generalization of Boltzmann-Gibbs thermostatistics by introducing a family of generalized nonextensive entropy functionals with a single parameter q. These reduce to the extensive Boltzmann-Gibbs form for q = 1, but a remarkable number of statistical and thermodynamic properties have been shown to be q-invariant - that is, valid for any q. In this paper, we address the question of whether or not the value of q for a given viscous, incompressible fluid can be ascertained solely by measurement of the fluid's hydrodynamic properties. We find that the hydrodynamic equations expressing conservation of mass and momentum are q-invariant, but the conservation of energy is not. Moreover, we find that ratios of transport coefficients may also be q-dependent. These dependences may therefore be exploited to measure q experimentally.
Parallel computation in a three-dimensional elastic-plastic finite-element analysis

A CRAY parallel processing technique called autotasking was implemented in a three-dimensional elasto-plastic finite-element code. The technique was evaluated on two CRAY supercomputers, a CRAY 2 and a CRAY Y-MP. Autotasking was implemented in all major portions of the code, except the matrix equations solver. Compiler directives alone were not able to properly multitask the code; user-inserted directives were required to achieve better performance. It was noted that the connect time, rather than wall-clock time, was more appropriate to determine speedup in multiuser environments. For a typical example problem, a speedup of 2.1 (1.8 when the solution time was included) was achieved in a dedicated environment and 1.7 (1.6 with solution time) in a multiuser environment on a four-processor CRAY 2 supercomputer. The speedup on a three-processor CRAY Y-MP was about 2.4 (2.0 with solution time) in a multiuser environment.
Denitrogenation of piperidine on alumina, silica, and silica-aluminas : the effect of surface acidity

Abstract Alumina, silica, and three silica-aluminas having 10, 50 and 90 wt% SiO 2 were prepared and characterized for the total acidity, acid strength distribution, and Bronsted/Lewis acidity. The characterization involved the techniques of ammonia chemisorption, temperature-programmed desorption (TPD), and FT-IR spectroscopy. The effect of surface acidity on denitrogenation selectivity was studied by means of the reactions of piperidine in a continuous-flow fixed-bed reactor operated at atmospheric pressure and 320–340°C. The overall piperidine conversion to various products increases with the total acidity of the catalysts. However, the denitrogenation selectivity depends only on the concentration of Bronsted acid sites, demonstrating the participation of those sites in the deamination mechanism and hence showing evidence for the Hofmann elimination pathway. The other important reactions of piperidine were alkylation, condensation, disproportionation, and dehydrogenation, to yield alkylpiperidines, 2,3,4,5-tetrahydropyridine, pyridine, 1,2,3,4-tetrahydroquinoline, 1,2,3,4-tetrahydro-3-methylquinoline, 5,6,7,8-tetrahydroquinoline, and decahydroquinoline.
One Voice or Many? The Political Question Doctrine and Acoustic Dissonance in Foreign Affairs

A common theme in foreign affairs law is the importance of the US speaking with “one voice” to the international community. Speaking with one voice, so the story goes, ensures that the US is not embarrassed by multiple, inconsistent pronouncements from the several states or the different branches of the national government when it takes a position on a foreign affairs issue. Such acoustic dissonance from the US could potentially result in a loss of credibility, a reduced capacity to achieve foreign policy goals, and a greater chance of conflict with other countries. So, when the Constitution is unclear about the allocation of decision-making authority on an issue, but the President or the national government speaks first, the presumption in favor of speaking in one voice reduces the possibility of multiple governmental decision makers and permits the US to act clearly and decisively in foreign affairs. While it reduces acoustic dissonance, the presumption in favor of one voice has two other effects as well: the centralization of foreign affairs decision making in the federal government vis-a-vis the states and centralization of foreign affairs decision making in the President vis-a-vis Congress.
Free radical ring-expansion leading to novel six- and seven-membered heterocycles

Abstract Free radical promoted ring-expansion of nitrogen-, oxygen- and sulfur-containing heterocyclic β-keto esters is described. Treatment of the derived phenylselenomethyl derivatives with tri-n-butyltin hydride leasds to smooth one-carbon ring expansion.
Cosmic-ray positrons: are there primary sources?

Abstract Galactic cosmic rays consist of primary and secondary particles. Primary cosmic rays are thought to be energized by first order Fermi acceleration processes at supernova shock fronts within our Galaxy. The cosmic rays that eventually reach the Earth from this source are mainly protons and atomic nuclei, but also include electrons. Secondary cosmic rays are created in collisions of primary particles with the diffuse interstellar gas. They are relatively rare but carry important information on the Galactic propagation of the primary particles. The secondary component includes a small fraction of antimatter particles, positrons and antiprotons. In addition, positrons and antiprotons may also come from unusual sources and possibly provide insight into new physics. For instance, the annihilation of heavy supersymmetric dark matter particles within the Galactic halo could lead to positrons or antiprotons with distinctive energy signatures. With the High-Energy Antimatter Telescope (HEAT) balloon-borne instrument, we have measured the abundances of positrons and electrons at energies between 1 and 50 GeV. The data suggest that indeed a small additional antimatter component may be present that cannot be explained by a purely secondary production mechanism. Here we describe the signature of the effect and discuss its possible origin.
The Effect of Disorder on Polymer Depinning Transitions

We consider a polymer, with monomer locations modeled by the trajectory of a Markov chain, in the presence of a potential that interacts with the polymer when it visits a particular site 0. We assume that probability of an excursion of length n is given by $$n^{-c}\varphi(n)$$ for some 1 < c < 2 and slowly varying $$\varphi$$ . Disorder is introduced by having the interaction vary from one monomer to another, as a constant u plus i.i.d. mean-0 randomness. There is a critical value of u above which the polymer is pinned, placing a positive fraction (called the contact fraction) of its monomers at 0 with high probability. To see the effect of disorder on the depinning transition, we compare the contact fraction and free energy (as functions of u) to the corresponding annealed system. We show that for c > 3/2, at high temperature, the quenched and annealed curves differ significantly only in a very small neighborhood of the critical point—the size of this neighborhood scales as $$\beta^{1/(2c-3)}$$ , where β is the inverse temperature. For c < 3/2, given $$\epsilon > 0$$ , for sufficiently high temperature the quenched and annealed curves are within a factor of $$1-\epsilon$$ for all u near the critical point; in particular the quenched and annealed critical points are equal. For c = 3/2 the regime depends on the slowly varying function $$\varphi$$ .
Do Photovoltaics have a Future

While there are several commercial businesses selling photovoltaic power supplies, the applications are all in places where conventional electric power is unavailable. The present interest in solar cell electricity for widespread terrestrial use has led to an intense activity exploring the opportunities for significant cost reduction. In this paper obstacles to cost reduction will be identified and the programs addressing techniques for overcoming those obstacles will be presented.
Do comets play a role in galactic chemistry and gamma-ray bursts

This paper explores the plausibility of the assumption that enough material from interstellar space is locked up in comets to reduce significantly the apparent growth rate of 'heavy' elements (mass greater than He) and, therefore, the present abundance of heavy elements in the interstellar medium and in the disk stars. A related suggestion concerns the influx of comets on neutron stars as a source of gamma-ray bursts. Although no interstellar comets have been observed, reasonable upper limits to the observed numbers and masses do not rule out the first suggestion. The gamma-ray-burst suggestion appears unlikely. A surprisingly large total mass of comets could be gravitationally bound to the sun and, of course, to other stars, but remain undetected. The nature of the 1908 Tunguska explosion is discussed briefly. It was probably not an encounter with an active comet.
A parallel rendezvous algorithm for interpolation between multiple grids

A number of computational procedures employ multiple grids on which solutions are computed. For example, in multiphysics simulations a primary grid may be used to compute mechanical deformation of an object while a secondary grid is used for thermal conduction calculations. When modeling coupled thermo-mechanical effects, solution data must be interpolated back and forth between the grids each timestep. On a parallel machine, this grid transfer operation can be challenging if the two grids are decomposed across processors differently for reasons of computational efficiency. If the grids move or adapt separately, the complexity of the operation is compounded. In this paper, we describe two grid transfer algorithms suitable for massively parallel simulations which use multiple grids. They use a rendezvous technique wherein a third decomposition is used to search for elements in one grid that contain nodal points of the other. This has the advantage of enabling the grid transfer operation to be load-balanced separately from the remainder of the computations. The algorithms are designed for use within the multi-physics code SIERRA, an object-oriented framework developed at Sandia. Performance and scalability results are given for the grid transfer operation running on up to 1024 processors of two large parallel machines, the Intel Tflops (ASCI Red) and DEC-Alpha CPlant cluster.
Fashion : From class differentiation to collective selection

(1969). Fashion: From Class Differentiation to Collective Selection. The Sociological Quarterly: Vol. 10, No. 3, pp. 275-291.
Local gradient estimates of solutions to some conformally invariant fully nonlinear equations

We establish local gradient estimates to solutions of general conformally invariant fully nonlinear second order elliptic equations. To cite this article: Y.Y. Li, C. R. Acad. Sci. Paris, Ser. I 343 (2006).
Sensing Power MOSFET Junction Temperature Using Circuit Output Current Ringing Decay

Junction temperature $(T_{j})$ sensing requirements for fast MOSFET junction temperature control and high-power fast switching power converter protection are not easily met with nonintrusive techniques. This paper presents a noninvasive circuit-model-based sensing method suitable for a high-bandwidth hard-switching converter power MOSFET junction temperature estimation without any additional temperature detector. For the purpose of demonstrating MOSFET junction temperature sensing, a chopper circuit is used. The ringing superimposed with a circuit load current is used for MOSFET junction temperature estimation. A “gate drive- $R_{\rm DS-on}{-}L{-}C$ ” resonant model is implemented, indicating the mechanism of power MOSFET turn-on dynamics. Modeling includes the gate-drive output parasitics, power MOSFET intrinsic parameters, PCB parasitics, and load parasitics. To evaluate the methodology, LTspice simulation and experimental results are studied.
8-Aminocyclazocine analogues: synthesis and structure-activity relationships.

Abstract Opioid binding affinities were assessed for a series of cyclazocine analogues where the prototypic 8-OH substituent of cyclazocine was replaced by amino and substituted-amino groups. For μ and κ opioid receptors, secondary amine derivatives having the (2 R ,6 R ,11 R )-configuration had the highest affinity. Most targets were efficiently synthesized from the triflate of cyclazocine or its enantiomers using Pd-catalyzed amination procedures.
PRODUCTIVITY AND INTERMEDIATE PRODUCTS: A FRONTIER APPROACH

Abstract In recent years, it has become popular to measure productivity using non-parametric approaches. However, this has been done while ignoring intermediate products. Here, we develop a non-parametric productivity measure that explicitly incorporates such products
Photon-gated spectral hole burning in LiGa 5 O 8 : Co 2 +

Photon-gated hole burning, or selective bleaching enabled by a second light source, has been observed in ${\mathrm{Co}}^{2+}$ in tetrahedral sites of ${\mathrm{LiGa}}_{5}$${\mathrm{O}}_{8}$. This leads to long-lived spectral holes with a width of \ensuremath{\sim}1 GHz at 1.6 K. It is proposed that two-step photoionization of ${\mathrm{Co}}^{2+}$ is responsible for the hole burning. Much narrower (\ensuremath{\sim}40 MHz) transient holes and antiholes were burned using population storage in nuclear hyperfine levels. These two mechanisms of hole burning are reported here for transition-metal ions for what is believed to be the first time.
Infrared limb-darkening effects for the earth-atmosphere system

An infrared radiative transfer model has been developed for evaluating anisotropic functions in the longwave region (5-50 microns) due to limb-darkening effects in the earth's atmosphere. An accurate narrow-band model of absorption has been used for computing transmission functions of the atmosphere. Absorption due to all major and minor atmospheric constituents has been taken into account including the continuum absorption due to water vapor. Anisotropic functions have been calculated for several latitudinal and seasonal climatological-average model atmospheres. The effects of the variability of various meteorological parameters, e.g. surface temperature, surface relative humidity, and cloud-top height have been examined. It has been found that the variability of cloud parameters has the largest effect on the infrared anisotropic functions.
Inner‐Phase Stabilization of Reactive Intermediates

Molecular container compounds are spherical, hollow molecules with inner cavities (inner phases) that are large enough to accommodate a single guest molecule. These inner phases are superb environments for the stabilization and spectroscopic investigation of important reactive intermediates. The surrounding host protects the incarcerated reactive intermediate from dimerization or from a reaction with bulk-phase reactants that are too large to enter the inner phase by passing through a portal in the host shell.
Copper-catalyzed oxidative Heck reactions between alkyltrifluoroborates and vinyl arenes

We report herein that potassium alkyltrifluoroborates can be utilized in oxidative Heck-type reactions with vinyl arenes. The reaction is catalyzed by a Cu(OTf)2/1,10-phenanthroline with MnO2 as the stoichiometric oxidant. In addition to the alkyl Heck, amination, esterification, and dimerization reactions of alkyltrifluoroborates are demonstrated under analogous reaction conditions. Evidence for an alkyl radical intermediate is presented.
A Universal Approach to Solvation Modeling

Continuum mean-field models that have been carefully designed to address the various electrostatic and nonelectrostatic interactions that develop between a molecule and a surrounding medium are particularly efficient tools for studying the effects of condensed phases on molecular structure, energetics, properties, spectra, interaction potentials, and dynamics. The SM8 model may be combined with density functional theory or Hartree–Fock theory to describe a solute’s electronic structure and its self-consistent-field polarization by a solvent. A key feature is the use of class IV charge models to obtain accurate charge distributions (either in the vapor phase or in solution), even when using small basis sets that are affordable for large systems. A second key feature is that nonelectrostatic effects due to cavity formation, dispersion interactions, and changes in solvent structure are included in terms of empirical atomic surface tensions that depend on geometry but do not require atom-type assignments by t...
Simulation of the flight experience of the ACIS CCDs on the Chandra X-ray Observatory

The energy resolution degradation of the ACIS CCDs on board the Chandra X-ray Observatory has been under investigation since the effect was first recognized two months after launch. A series of laboratory CCD irradiations with electrons and protons have taken place, leading to the belief that low energy protons are responsible for the damage. In order to confirm this, an experiment has been devised to represent the flight experience of the ACIS CCDs, and the results to date are shown here.
Quantifying baryon stopping in high energy nuclear collisions

Abstract We propose a numerical definition for baryon stopping in relativistic heavy ion collisions that is obtainable from final hadron rapidity distributions as well as from bremsstrahlung measurements. Thus a new channel of communication is opened between the two methods.
The Direct Catalytic Asymmetric Aldol Reaction

Asymmetric aldol reactions are a powerful method for the construction of carbon–carbon bonds in an enantioselective fashion. Historically this reaction has been performed in a stoichiometric fashion to control the various aspects of chemo-, diastereo-, regio- and enantioselectivity, however, a more atom economical approach would unite high selectivity with the use of only a catalytic amount of a chiral promoter. This critical review documents the development of direct catalytic asymmetric aldol methodologies, including organocatalytic and metal-based strategies. New methods have improved the reactivity, selectivity and substrate scope of the direct aldol reaction and enabled the synthesis of complex molecular targets (357 references).