cssi/SciSciGPT-SciSciNet huggingface dataset:
Foreclosure with Incomplete Information

We investigate the robustness of the new foreclosure doctrine and its associated welfare implications to the introduction of incomplete information. In particular, we let the upstream firm's marginal cost be private information, unknown to the downstream firms. The previous literature has argued that vertical integration is harmful because it allows an upstream monopolist to limit output to monopoly levels, whereas a disintegrated structure will “over-sell,” producing more in equilibrium. By contrast, we find that with incomplete information, high-cost firms will often “under-sell” in equilibrium, that is, supply less than their monopoly output. Low-cost firms continue to over-sell, so all types of firms have a reason to integrate downstream, but this is socially harmful only for low-cost types. For high-cost firms vertical integration can be Pareto-improving, resulting in higher output, profits, and consumer surplus.
Scope and Mechanism for Lewis Acid-Catalyzed Cycloadditions of Aldehydes and Donor−Acceptor Cyclopropanes: Evidence for a Stereospecific Intimate Ion Pair Pathway

In this work, the one-step diastereoselective synthesis of cis-2,5-disubstituted tetrahydrofurans via Lewis acid catalyzed [3 + 2] cycloadditions of donor-acceptor (D-A) cyclopropanes and aldehydes is described. The scope and limitations with respect to both reaction partners are provided. A detailed examination of the mechanism has been performed, including stereochemical analysis and electronic profiling of both reactants. Experimental evidence supports an unusual stereospecific intimate ion pair mechanism wherein the aldehyde functions as a nucleophile and malonate acts as the nucleofuge. The reaction proceeds with inversion at the cyclopropane donor site and allows absolute stereochemical information to be transferred to the products with high fidelity. The mechanism facilitates the stereospecific synthesis of a range of optically active tetrahydrofuran derivatives from enantioenriched D-A cyclopropanes.
On the 2:1 Orbital Resonance in the HD 82943 Planetary System

We present an analysis of the HD 82943 planetary system based on a radial velocity data set that combines new measurements obtained with the Keck telescope and the CORALIE measurements published in graphical form. We examine simultaneously the goodness of fit and the dynamical properties of the best-fit double-Keplerian model as a function of the poorly constrained eccentricity and argument of periapse of the outer planet's orbit. The fit with the minimum ? is dynamically unstable if the orbits are assumed to be coplanar. However, the minimum is relatively shallow, and there is a wide range of fits outside the minimum with reasonable ?. For an assumed coplanar inclination i = 30? (sin i = 0.5), only good fits with both of the lowest order, eccentricity-type mean-motion resonance variables at the 2?:?1 commensurability, ?1 and ?2, librating about 0? are stable. For sin i = 1, there are also some good fits with only ?1 (involving the inner planet's periapse longitude) librating that are stable for at least 108 yr. The libration semiamplitudes are about 6? for ?1 and 10? for ?2 for the stable good fit with the smallest libration amplitudes of both ?1 and ?2. We do not find any good fits that are nonresonant and stable. Thus, the two planets in the HD 82943 system are almost certainly in 2?:?1 mean-motion resonance, with at least ?1 librating, and the observations may even be consistent with small-amplitude librations of both ?1 and ?2.
Bargaining with commitment between workers and large firms

Abstract I study the efficiency of search equilibrium under decreasing returns to labor in production. Firms can sign long-term contracts with their workers which give them incentives to maximize the joint surplus associated with their relationship. When the firm hires a new worker, the terms of the contract are determined by bargaining over the marginal surplus. Long-term contracts solve the over-hiring problem identified by previous authors. However, the equilibrium is still not constrained efficient because large, low productivity firms search too intensively relative to small, high productivity firms. This potentially provides a novel justification for subsidizing vacancy creation by young, small firms.
Seniority in Legislatures

We construct a stochastic game model of a legislature with an endogenously determined seniority system. We model the behavior of the legislators as well as their constituents in an infinitely repeated divide the dollar game. Each legislative session must make a decision on redistributional issues, modeled as a divide the dollar game. However, each session begins with a vote in which the legislators decide, by majority rule, whether or not to impose on themselves a seniority system. Legislative decisions on the redistributional issues are made by the Baron-Ferejohn rule: an agenda setter is selected by a random recognition rule (which in our model is a function of the seniority system selected), the agenda setter makes a proposal on redistributional issues, and the legislature then votes whether to accept or reject the agenda setters proposal. If the legislature rejects the proposal, another agenda setter is randomly selected, and the process is repeated. If the legislature accepts the proposal, the legislative session ends, and the voters in each legislative district vote whether to retain their legislator or throw it out of office. The voters' verdict determines the seniority structure of the next period legislature. We find a stationary equilibrium to the game having the property that the legislature imposes on itself a non trivial seniority system, and that legislators are always reelected.
Low-complexity smoother (LO-COST) for low-bit-rate codecs

videoconferencing applications. The algorithm analyzes the image from the perspective of the human viewer, classifiespixels according to local characteristics, and applies combinations of linear and non-linear filters to each class. Edge pixelsare sharpened, pixels near edges have a median filter applied to mitigate mosquito noise, and pixels in monotonous regionsare smoothed to dampen blocking. The algorithm requires limited processing and can be used independently of thevideoconferencing standard that is used. Objective analysis shows that errors are decreased for a majority of pixels. Insubjective tests using low bit-rate coding standards, processed sequences were judged to significantly improve the imagequality of the decoded sequences in all cases.Keywords: DSP, videoconferencing, postprocessing, low bit-rates, artifacts, blocking, mosquito noise1. INTRODUCTIONThe encoding/decoding process of video teleconferencing and videophone applications introduces unwanted noiseartifacts into the reconstructed sequences. These artifacts detract from the intelligibility of the transmission and areespecially evident when using very low bit-rates. Postprocessing routines can be effective tools in eliminating or at leastmasking much of the blocking and mosquito noise found in decoded images.Minami and Zakhor [1] demonstrated that blocking artifacts could be reduced using an optimization technique on DCTcoefficients when the block boundaries are clearly defined. This optimization scheme significantly reduces blocking, butrelies on a full set of DCT coefficients for the entire image. Video codec standards that employ motion prediction, such as
Platinum Diffusion Barrier Breakdown in a-Si/Au Eutectic Wafer Bonding

Eutectic bonding in semiconductor fabrication requires a large degree of control over the stoichiometry and precision film thickness of the bonding materials. To reduce the migration of the bonding layers, diffusion barriers are typically utilized. Here, we demonstrate that a widely utilized diffusion barrier, Pt, does not prevent migration of Si in Si/Au eutectic bonding. We observe that this barrier breaks down at approximately 375°C, above the Au-Si eutectic temperature (363°C), and encourages consumption of the silicon substrate leading to uncontrolled stoichiometry variations and creation of microvoids. This failure results in reductions of bond strength and hermeticity. As an alternative, silicon dioxide is observed to prevent the silicon diffusion and subsequent substrate loss.
Computer-aided design of host molecules for recognition of organic guests

Abstract This paper presents an overview of a computational approach to design molecular host architectures. After positioning donor groups about a targeted guest molecule, the donor groups are connected with hydrocarbon linkages taken from an extensive database of molecular fragments. Initial ranking of the host structures is based on how well bond vectors on the donor groups match bond vectors on the linkages. The top candidates are then subjected to further evaluation with molecular mechanics identifying host architectures that are both complementary and preorganized for binding the guest. The efficacy of this computer-aided design methodology is illustrated with a search for hydrogen bonding receptors that are structurally organized for complexation with oxygen mustard.
Quantum Computing with Neutral Atoms in An Optical Lattice

We present a proposal for quantum information processing with neutral atoms trapped in optical lattices as qubits. Initialization and coherent control of single qubits can be achieved with standard laser cooling and spectroscopic techniques. We consider entangling two-qubit logic gates based on optically induced dipole-dipole interactions, calculating a figure-of-merit for various protocols. Massive parallelism intrinsic to the lattice geometry makes this an intriguing system for scalable, fault-tolerant quantum computation.
Unexpected consequences of methyl substitutions in supramolecular chemistry

We consider here the not-so-subtle effects of small changes in molecular modules that self-assemble into supramolecular complexes. In particular, the substitutions of methyl groups for hydrogens and the reverse have consequences far beyond simple steric effects. The most profound of these effects deals with container molecules that create encapsulation complexes.
Distributed Averaging in Dynamic Networks

The question of computing average of numbers present at nodes in a network in a distributed manner using gossip or message-passing algorithms has been of great recent interest across disciplines-algorithms, control and robotics, estimation, social networks, etc. It has served as a non-trivial, representative model for an important class of questions arising in these disciplines and thus guiding intellectual progress over the past few decades. In most of these applications, there is inherent dynamics present, such as changes in the network topology in terms of communication links, changes in the values of numbers present at nodes, and nodes joining or leaving. The effect of dynamics in terms of communication links on the design and analysis of algorithms for averaging is reasonably well understood, e.g., J. Tsitsiklis, “Problems in decentralized decision making and computation,” Ph.D. dissertation, MIT, 1984; D. Bertsekas , “Convergence theories of distributed iterative processes: A survey,” MIT, 1983; A. Jadbabaie , “Coordination of groups of mobile autonomous agents using nearest neighbor rules,” IEEE Trans. on Automatic Control, vol. 48, no. 6, pp. 988-1001, 2003; S. Boyd , “Gossip algorithms: Design, analysis and applications,” Proc. IEEE INFOCOM, 2005, pp. 1653-1664. However, little is known about the effect of other forms of dynamics. In this paper, we study the effect of such types of dynamics in the context of maintaining average in the network. Specifically, we design dynamics-aware message-passing or gossip algorithm that maintains good estimate of average in presence of continuous change in numbers at nodes. Clearly, in presence of such dynamics the best one can hope for is a tradeoff between the accuracy of each node's estimate of the average at each time instant and the rate of dynamics. For our algorithm, we characterize this tradeoff and establish it to be near optimal. The dependence of the accuracy of the algorithm on the rate of dynamics as well as on the underlying graph structure is quantified.
Input-output relations in biological systems: measurement, information and the Hill equation

Biological systems produce outputs in response to variable inputs. Input-output relations tend to follow a few regular patterns. For example, many chemical processes follow the S-shaped Hill equation relation between input concentrations and output concentrations. That Hill equation pattern contradicts the fundamental Michaelis-Menten theory of enzyme kinetics. I use the discrepancy between the expected Michaelis-Menten process of enzyme kinetics and the widely observed Hill equation pattern of biological systems to explore the general properties of biological input-output relations. I start with the various processes that could explain the discrepancy between basic chemistry and biological pattern. I then expand the analysis to consider broader aspects that shape biological input-output relations. Key aspects include the input-output processing by component subsystems and how those components combine to determine the system’s overall input-output relations. That aggregate structure often imposes strong regularity on underlying disorder. Aggregation imposes order by dissipating information as it flows through the components of a system. The dissipation of information may be evaluated by the analysis of measurement and precision, explaining why certain common scaling patterns arise so frequently in input-output relations. I discuss how aggregation, measurement and scale provide a framework for understanding the relations between pattern and process. The regularity imposed by those broader structural aspects sets the contours of variation in biology. Thus, biological design will also tend to follow those contours. Natural selection may act primarily to modulate system properties within those broad constraints. This article was reviewed by Eugene Koonin, Georg Luebeck and Sergei Maslov.
Regio- and Stereoselective Copper-Catalyzed Synthesis of Vicinal Haloamino Ketones from α,β-Unsaturated Ketones

The regio- and stereoselective aminochlorination of α,β-unsaturated ketones has been developed. The reaction was conducted with N,N-dichloro-p-toluenesulfonamide (4-TsNCl2) as the nitrogen/halogen source and CuOTf as the catalyst, at 0 °C to room temperature. This method provides an easy access to vicinal haloamino ketones, with excellent regioselectivity and up to quantitative yields. Both aromatic and aliphatic enones react well with 4-TsNCl2 under the present system, but give opposite regioselectivity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Biological inactivation of progesterone by interaction with corticosteroid-binding globulin and with albumin.

Addition of a rat CBG preparation to a progesterone solution abolished the effect of the hormone on the ligated uterus of the ovariectomized mouse. Inactivation was also observed when rat serum albumin was used as the progesterone-binding protein. These results seem to show that the biological activity of progesterone is suppressed by complex formation with CBG or with serum albumin. (Endocrinology 85: 778, 1969)
Optimal Moments for the Analysis of Peculiar Velocity Surveys

We present a new method for the analysis of peculiar velocity surveys that removes contributions to velocities from small scale, nonlinear velocity modes while retaining information about large-scale motions. Our method utilizes Karhunen-Loeve methods of data compression to construct a set of moments out of the velocities that are minimally sensitive to small-scale power. The set of moments are then used in a likelihood analysis. We develop criteria for the selection of moments, as well as a statistic to quantify the overall sensitivity of a set of moments to small-scale power. Although we discuss our method in the context of peculiar velocity surveys, it may also prove useful in other situations where data filtering is required.
Numerical methods for high-speed computers: a survey

Numerical analysis is the science and art of using digital computing machines to carry out scientific computations, excluding pure data processing. Because of the recent changes in computers, the field is dominated today by the problems of using the large stored-program digital computers. Analog computers, though important both for their output and as a source of methods (too seldom exploited) for digital computers, are not considered here. It is possible to give a rough mathematical classification of the types of computing problems ordinarily met. The following classification is adapted from Forsythe [4].
Pulsed flow modulation of soot production in a laminar jet-diffusion flame

Abstract An axisymmetric, co-flow, acetylene–air diffusion flame was driven by an acoustic source at frequencies ranging from 230 to 1000 Hz and powers of 0–10 W. Soot concentration was measured both locally within the flame and globally far downstream of the flame. The acoustic characteristics of the system are detailed in this manuscript. We show that the acoustic velocity at the fuel exit plane strongly affects the soot concentration within the flame and emitted by the flame. When the acoustic velocity magnitudes are much larger than the mean fuel velocity, the average soot number concentration measured far downstream of the flame was reduced by almost three orders of magnitude. A simple scaling analysis is performed to show that a partial premixing mechanism may be responsible for the observed changes to the soot properties of the flame. To test this hypothesis, sooting properties of partially premixed flames were characterized over a range of equivalence ratios in the same burner. While initial addition of air into the fuel stream slightly increased the amount of soot released, further addition of air suppressed soot production. Comparisons of the acoustically forced flames to partially premixed flames support the hypothesis that the acoustic field aids in partially premixing the flame.
Constraining the Lifetime of Quasars from Their Spatial Clustering

The lifetime of the luminous phase of quasars is constrained by current observations to be 106 tQ 108 yr but is otherwise unknown. We model the quasar luminosity function in detail in the optical and X-ray bands using the Press-Schechter formalism and show that the expected clustering of quasars depends strongly on their assumed lifetime tQ. We quantify this dependence and find that existing measurements of the correlation length of quasars are consistent with the range 106 tQ 108 yr. We then show that future measurements of the power spectrum of quasars out to z ~ 3, from the Anglo-Australian Telescope Two-Degree Field or Sloan Digital Sky Survey, can significantly improve this constraint and in principle allow a precise determination of tQ. We estimate the systematic errors introduced by uncertainties in the modeling of the quasar-halo relationship, as well as by the possible existence of obscured quasars.
A Simple Proof of Hardy-Lieb-Thirring Inequalities

We give a short and unified proof of Hardy-Lieb-Thirring inequalities for moments of eigenvalues of fractional Schrodinger operators. The proof covers the optimal parameter range. It is based on a recent inequality by Solovej, Sorensen, and Spitzer. Moreover, we prove that any non-magnetic Lieb-Thirring inequality implies a magnetic Lieb-Thirring inequality (with possibly a larger constant).
Well-rounded zeta-function of planar arithmetic lattices

We investigate the properties of the zeta-function of well-rounded sublattices of a fixed arithmetic lattice in the plane. In particular, we show that this function has abscissa of convergence at s = 1 with a real pole of order 2, improving upon a result of (11). We use this result to show that the number of well-rounded sublattices of a planar arithmetic lattice of index less or equal N is O(N logN) as N ! 1. To obtain these results, we produce a description of integral well-rounded sublattices of a fixed planar integral well- rounded lattice and investigate convergence properties of a zeta-function of similarity classes of such lattices, building on the results of (7).
Electron tunneling and superconductivity

Work on tunneling between superconductors is discussed and some experimental results are given. 2 refs.
Examples of the construction of integral equations in equilibrium statistical mechanics from invariance principles

Abstract The integral equation which identically relates the gradient of the density ▿ϱ(r) and the Ornstein-Zernike direction correlation function c(r.r′) is derived from a simple but fundamental invariance principle. This generalization of the heuristic translational invariance argument used in the past establishes that this integral equation is valid even in the presence of intermolecular forces which are not translationally invariant. The same methodology can be used to generate all the integral equations in the hierarchy of relations between ▿ϱ(r) and higher-order direct correlation functions. It is also observed that, as one can proceed up the hierarchy by simple functional differentiation, it is also possible to proceed down the hierarchy. In particular, the generation of the first member of the hierarchy from the second provides a derivation of this relation which closely parallels the derivation of the first member of the Born-Green-Yvon hierarchy. The hierarchy of integral equations based upon rotational invariance is similarly developed.
Polynomial Relations Among Characters coming from Quantum Affine Algebras

The Jacobi-Trudi formula implies some interesting quadratic identities for characters of representations of gln. Earlier work of Kirillov and Reshetikhin proposed a generalization of these identities to the other classical Lie algebras, and conjectured that the characters of certain finite-dimensional representations of Uq(ĝ) satisfy it. Here we use a positivity argument to show that the generalized identities have only one solution.
Reforming medicare: Impacts on federal spending and choice of health plans

ABSTRACT: The rising cost of Medicare and well-documented problems plaguing Medicare+Choice (M+C) have increased interest in “reforming” the program. To improve efficiency, most reform proposals wo...
Stereospecific decarboxylative allylation of sulfones.

Allyl sulfonylacetic esters undergo highly stereospecific, palladium-catalyzed decarboxylative allylation. The reaction allows the stereospecific formation of tertiary homoallylic sulfones in high yield. In contrast to related reactions that proceed at −100 °C and require highly basic preformed organometallics, the decarboxylative coupling described herein occurs under mild nonbasic conditions and requires no stoichiometric additives. Allylation of the intermediate α-sulfonyl anion is more rapid than racemization, leading to a highly enantiospecific process. Density functional theory calculations indicate that the barrier for racemization is 9.9 kcal/mol, so the barrier for allylation must be <9.9 kcal/mol.
An arbitrary Lagrangian-Eulerian discretization of MHD on 3D unstructured grids

Abstract We present an arbitrary Lagrangian–Eulerian (ALE) discretization of the equations of resistive magnetohydrodynamics (MHD) on unstructured hexahedral grids. The method is formulated using an operator-split approach with three distinct phases: electromagnetic diffusion, Lagrangian motion, and Eulerian advection. The resistive magnetic induction equation is discretized using a compatible mixed finite element method with a second order accurate implicit time differencing scheme which preserves the divergence-free nature of the magnetic field. At each discrete time step, electromagnetic force and heat terms are calculated and coupled to the hydrodynamic equations to compute the Lagrangian motion of the conducting materials. By virtue of the compatible discretization method used, the invariants of Lagrangian MHD motion are preserved in a discrete sense. When the Lagrangian motion of the mesh causes significant distortion, that distortion is corrected with a relaxation of the mesh, followed by a second order monotonic remap of the electromagnetic state variables. The remap is equivalent to Eulerian advection of the magnetic flux density with a fictitious mesh relaxation velocity. The magnetic advection is performed using a novel variant of constrained transport (CT) that is valid for unstructured hexahedral grids with arbitrary mesh velocities. The advection method maintains the divergence-free nature of the magnetic field and is second order accurate in regions where the solution is sufficiently smooth. For regions in which the magnetic field is discontinuous (e.g. MHD shocks) the method is limited using a novel variant of algebraic flux correction (AFC) which is local extremum diminishing (LED) and divergence preserving. Finally, we verify each stage of the discretization via a set of numerical experiments.
Breakdown of the integer and fractional quantum Hall states in a quantum point contact

Abstract The integer and fractional quantum Hall states are known to breakdown at high dc bias, exhibiting deviation from the ideal incompressible behavior. We measure breakdown of the ν=2, 3, 4, 5 integer and the ν=4/3 and 5/3 fractional states in a quantum point contact (QPC) of lithographic width ∼600 nm. Dependence of the critical current on magnetic field, QPC gate voltage, and QPC width are presented. Of particular interest, the critical current of the 4/3 and 5/3 fractional states shows the opposite dependence on QPC width compared to the integer states. This previously unobserved result is not explained by current theories of breakdown.
A Novel Electrochemical Method for Measuring Salt Diffusion Coefficients and Ion Transference Numbers

We have found it possible to determine salt diffusion coefficients and ion transference numbers by obtaining, respectively, the steady-state ion-transport-limited current at a microdisk electrode in spherical diffusion geometry and the transient ion-transport-limited current at a macrodisk electrode in planar diffusion geometry in ionic solutions containing no supporting electrolyte. The method is demonstrated in aqueous solutions of AgNO 3 and in propylene carbonate solutions of LiClO 4 . The ion transport parameters obtained agree well with those reported previously. It would appear that the method also could be used in the study of ion transport in solid electrolytes
Regioselective and enantiospecific rhodium-catalyzed allylic alkylation reactions using copper(I) enolates: synthesis of (-)-sugiresinol dimethyl ether.

The transition metal-catalyzed allylic alkylation represents a fundamentally important cross-coupling reaction for the construction of ternary carbon stereogenic centers. We have developed a regioselective and enantiospecific rhodium-catalyzed allylic alkylation of acyclic unsymmetrical allylic alcohol derivatives using copper(I) enolates to prepare β-substituted ketones. This protocol represents a convenient asymmetric Claisen rearrangement surrogate in which α-substituted enolates permit the introduction of an additional stereogenic center. The synthetic utility of this transformation was highlighted in the construction of a trans-1,2-disubstituted cyclohexene and the total synthesis of (−)-sugiresinol dimethyl ether. Finally, we anticipate that copper(I) enolates may prove useful nucleophiles in related metal-catalyzed reactions.
The Downstream Benefits of Experimentation

The debate about the cost-effectiveness of randomized field experimentation ignores one of the most important potential uses of experimental data. This article defines and il lustrates "downstream" experimental analysis?that is, analysis of the indirect effects of experimental interventions. We argue that downstream analysis may be as valuable as conventional analysis, perhaps even more so in the case of laboratory experimentation.
Structural Characterization and Biological Effects of Photocyclized Products of Tamoxifen Irradiation

Tamoxifen (TAM) is an antiestrogen useful in the treatment and control of breast cancer. Exposure of solutions of TAM to UV irradiation produces mixtures of fluorescent derivatives that are useful in the analytical detection and quantitative determination of TAM. The two major products of such irradiations were isolated and assigned unambiguous structures based on analysis of UV and 1H NMR spectral data. Results were in accordance with earlier studies that indicated these products to be substituted phenanthrenes produced by dehydrogenation of cyclized intermediates subsequent to partial isomerization of TAM. Each of the phenanthrenes suppressed MCF-7 human breast cancer cell growth in a dose-dependent manner, but neither compound was as potent as TAM in this regard. Also, unlike treatment with TAM, cell growth could not be restored in the presence of either of the phenanthrenes by simultaneous exposure to estradiol.
Microaperture high-speed ferrite memory

Present day digital computers universally employ ferrite cores for random storage. Available memories, operating in a current coincident mode, have capacities up to approximately 2 × 106 bits and cycle times in the neighborhood of 10 microseconds [1]. Shorter cycle times around 1 microsecond have been achieved in commerical systems by resorting to a word organized mode of operation [2]. Because of the increased cost of the required electronic circuitry, bit capacities are in general less than those of a coincident current store.
Recent developments and applications of electron microscopy to heterogeneous catalysis.

Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) are popular and powerful techniques used to characterize heterogeneous catalysts. Rapid developments in electron microscopy – especially aberration correctors and in situ methods – permit remarkable capabilities for visualizing both morphologies and atomic and electronic structures. The purpose of this review is to summarize the significant developments and achievements in this field with particular emphasis on the characterization of catalysts. We also highlight the potential and limitations of the various methods, describe the need for synergistic and complementary tools when characterizing heterogeneous catalysts, and conclude with an outlook that also envisions future needs in the field.
Reactions of perfluorocycloimines with (polyfluoroalkoxy)trimethylsilanes and polyfluoroalkyltrifluoromethanesulfonates

Abstract The reactions of F -(5,6-dihydro-2 H -1,4-oxazine) and F -(3,4-dihydro-2 H -pyrrole) were investigated using two series of reagents: one is the polyfluoroalkylating agent RfOSO 2 CF 3 and the other is the (polyfluoroalkoxy)trimethylsilane RfOSi(CH 3 ) 3 . Systematic study with polyfluoroalkyl groups such as CF 3 CH 2 , C 2 F 5 CH 2 , CHF 2 CH 2 , and (CF 3 ) 2 CH revealed that the regio-chemistry, isomer distribution, product distribution between mono-, di-, and tri-substituted products and even the reaction pathways were subtly changed by the structure of these fluoro substituents as well as by the reagent stoichiometry. A notable substitution effect was found in the reaction of F -(5,6-dihydro-2 H -1,4-oxazine): substitution at the 3-position prevented the N -polyfluoroalkylation by CF 3 CH 2 OSO 2 CF 3 . No particular difference was found between the two different heterocyclic systems in contrast with the reaction of these heterocyclic systems with C 6 F 5 Si(CH 3 ) 3 . The discussion about the reaction mechanisms for both reagents are included.
Episodic Non-Markov Localization: Reasoning About Short-Term and Long-Term Features

Markov localization and its variants are widely used for localization of mobile robots. These methods assume Markov independence of observations, implying that observations made by a robot correspond to a static map. However, in real human environments, observations include occlusions due to unmapped objects like chairs and tables, and dynamic objects like humans. We introduce an episodic non-Markov localization algorithm that maintains estimates of the belief over the trajectory of the robot while explicitly reasoning about observations and their correlations arising from unmapped static objects, moving objects, as well as objects from the static map. Observations are classified as arising from longterm features, short-term features, or dynamic features, which correspond to mapped objects, unmapped static objects, and unmapped dynamic objects respectively. By detecting time steps along the robot’s trajectory where unmapped observations prior to such time steps are unrelated to those afterwards, nonMarkov localization limits the history of observations and pose estimates to “episodes” over which the belief is computed. We demonstrate non-Markov localization in challenging real world indoor and outdoor environments over multiple datasets, comparing it with alternative state-of-the-art approaches, showing it to be robust as well as accurate.
Stereoselectivity in the synthesis of tetramethylethano-bridged 3,3'-di-tert-butyltitanocene dichloride

Abstract Racemic and meso ansa-(2,3-dimethyl-2,3-butano)-3,3′-bis(1,1′-dimethylethyl)cyclopenta-1,3-dien-5-yl)titanium dichloride (5 and 4) were prepared in a 1:4 to 1:2 ratio by the addition of TiCl3·3THF to 2,3-bis[3-(1,1-dimethylethyl)-1,3-cyclopentadien-5-yl]2,3-dimethylbutanedilithium (3) in THF with subsequent oxidation by HCl in a 44% yield. A 30% yield of the 1:1 racemic:meso ratio resulted when 3 was treated with titanocene dichloride in THF followed by carbon tetrachloride oxidation. In the attempts to synthesize the desired anti isomer, 3 was treated with in-situ generated racemic dichloro-1,1′-bi-2-naphtholatetitanium(IV) to give ansa-(2,3-dimethyl-2,3-butano)-anti-3,3′-bis(1,1-dimethy lethyl)cyclopenta-1,3-dien-5-yl)titanium 1,1′-bi-2-naphtholate (6) in a 10–15% yield. 6 crystallized in a monoclinic space group P21/c with a = 10.084(2) A, b = 29.312(7) A, c = 12.190(2) A, β = 99.37(2)°, V = 355(2) A3, and Z = 4. Refinement of 425 least squares variables converged to R = 0.044 and Rw = 0.046 for 4153 observed reflections with I > 2δ(I). The molecule contains an approximate C2 axis of symmetry with the t-butyl groups anti to each other. The C(Cp)C(t-butyl) bonds are displaced from the plane defined by the cyclopentadienyls by about 10°.
Vagaries of density functional theory of the liquid-vapor interface

Abstract The (direct) potential functional and (inverse) density functional formulations of classical equilibrium statistical mechanics are reviewed, and their local thermodynamic limits presented. Both are extended, in particular for interfacial structure, in Van der Waals mean field theory. The direct generator, the grand potential, is transformed by the Kac-Siegert approach and the profile equation approximated. The indirect free energy functional is expanded in interaction strength. Both approaches fail to combine consistency with known profile softening under weak external fields. The Kac-Siegert form is then rewritten in terms of a distribution of interfacial surfaces alone for a special model, and transformed to inverse format for a two-dimensional system, yielding a free energy density functional which involves a deaveraged density field, and has the expected interfacial properties.
Overlayer-induced anomalous interface magnetocrystalline anisotropy in ultrathin Co films.

The full-potential linearized augmented-plane-wave method with the atomic force approach has been used to determine the interface structure and magnetocrystalline anisotropy (MCA) of a Co monolayer on Cu(111), with and without Cu overlayers. It is found in good agreement with experiment, that the interface MCA for a fully relaxed structure is in-plane with a value of --0.30 meV for Co monolayer (ML) on Cu(111). When capped with nonmagnetic Cu, the interface MCA changes dramatically: for one ML Cu coverage, it is perpendicular to the film plane with a MCA value of + 0.23 meV; for two ML Cu coverage, it rapidly drops to --0.02 meV. Our results confirm that the hybridization at the Co/Cu interface plays an important role in the interface MCA of Co/Cu systems. By comparing the results of the fully relaxed structures with those of unrelaxed structures, we also found that relaxation is important for accurate determinations of the interface MCA. \textcopyright{} 1996 The American Physical Society.
Two-dimensional packing of soft particles and the soft generalized Thomson problem

We perform numerical simulations of a model of purely repulsive soft colloidal particles interacting via a generalized elastic potential and constrained to a two-dimensional plane and to the surface of a spherical shell. For the planar case, we compute the phase diagram in terms of the system's rescaled density and temperature. We find that a large number of ordered phases becomes accessible at low temperatures as the density of the system increases, and we study systematically how structural variety depends on the functional shape of the pair potential. For the spherical case, we revisit the generalized Thomson problem for small numbers of particles N ≤ 12 and identify, enumerate and compare the minimal energy polyhedra established by the location of the particles to those of the corresponding electrostatic system.
Sum Rate of the Vacationing-CEO Problem

The vacationing chief executive officer (CEO) problem combines the salient features of the so-called CEO problem and the multiple-description (MD) problem. In this setting, noisy versions of a source are observed by two encoders, as in the CEO problem. In addition, we require that each encoder generate MDs of the source, as in the MD problem. The vacationing-CEO problem arises in asynchronous multicast networks, and solving it is an essential step in developing a general theory for multiencoder and multidecoder lossy compression. In this paper, an achievable sum rate and two sum rate lower bounds are presented for the quadratic Gaussian vacationing-CEO problem. These bounds exactly determine the optimal sum rate over a wide range of parameters.
Do exports generate higher productivity? Evidence from Slovenia

Abstract I use matched sampling techniques to analyze whether firms that start exporting become more productive, controlling for the self-selection into export markets. To this end, I use micro data of Slovenian manufacturing firms operating in the period 1994–2000. Overall I find that export entrants become more productive once they start exporting. The productivity gap between exporters and their domestic counterparts increases further over time. These results also hold at the industry level and are robust to other controls that may be associated with increased productivity, such as private ownership. Using information on the (firm-level) destination of exports, I find that the productivity gains are higher for firms exporting towards high income regions.
The emergence of a profession

Computer programming deals with an enormous variety of activities and is carried on by people with a great variety of backgrounds. It seems clear that part but not all of this activity is evolving toward a distinct professional field, but that the scope of this emerging profession, and some of its economic, social, and educational characteristics are as yet by no means well defined. In this paper, these issues are examined and some opinions about them are expressed.
A lattice model of fractional statistics

Abstract We present a new formulation of Chern-Simons theory on a three-dimensional lattice, with either the linear gauge group R or the finite cyclic gauge group Z N . By coupling extended objects called dumb-bells to the lattice Chern-Simons field, we obtain a model exhibiting fractional statistics in the continuum limit. Internal dumb-bell angular momenta take values consistent with their statistics. The Z N - model has a gauge-decoupled condensate. Either model can admit a Maxwell term.
Complex adaptive systems engineering (CASE)

We suggest a portfolio of distinct but related systems engineering activities that collectively may work well in very difficult environments. The CASE methodology acknowledges the human factor and encourages exerting influence rather than control. We advocate their consideration and application in limited domains, at first, to gain confidence in their viability.
A new formulation of the near-equilibrium theory of turbulence

We present a status report on a discrete approach to the the near-equilibrium statistical theory of three-dimensional turbulence, which generalizes earlier work by no onger requiring that the vorticity field be a union of discrete vortex filaments. The idea is to take a special limit of a dense lattice vortex system, in a way that brings out a connection between turbulence and critical phenomena. The approach produces statistics with basic features of turbulence, in particular intermittency and coherent structures. The numerical calculations have not yet been brought to convergence, and at present the results are only qualitative.
Transshipment of Inventories Among Retailers: Myopic vs. Farsighted Stability

The author considers a model of a decentralized distribution system consisting of n retailers selling an identical product. Retailers face a stochastic demand and must order their initial inventory before this demand is realized. After demand realization, retailers decide how much of their unsold inventory or unsatisfied demand they want to share with other retailers. This is followed by a transshipment of leftover inventories and distribution of the additional profit generated through inventory sharing. The author addresses the following issue: Suppose that the retailers distribute the profit from inventory sharing according to an allocation rule that induces retailers to share their residuals in a way that maximizes the additional profit, such as the Shapley value, but may not belong to the core. Is it likely that, in this framework, all retailers will jointly share their residuals and not form subcoalitions? Previous research has looked at this problem from a myopic viewpoint and concluded that the grand coalition is not stable. Unlike the prior work, the author looks at stability in a farsighted sense. That is, retailers do not consider only their immediate payoffs but are also concerned with reactions of other retailers to their actions. In a symmetric setting, with identical additional unit revenues from transshipments generated by all retailers, farsighted retailers always maximize their allocations by not defecting from the grand coalition. The author also provides conditions when the same is true for nonidentical additional unit revenues.
Learning policies for battery usage optimization in electric vehicles

The high cost, limited capacity, and long recharge time of batteries pose a number of obstacles for the widespread adoption of electric vehicles. Multi-battery systems that combine a standard battery with supercapacitors are currently one of the most promising ways to increase battery lifespan and reduce operating costs. However, their performance crucially depends on how they are designed and operated. In this paper, we formalize the problem of optimizing real-time energy management of multi-battery systems as a stochastic planning problem, and we propose a novel solution based on a combination of optimization, machine learning and data-mining techniques. We evaluate the performance of our intelligent energy management system on various large datasets of commuter trips crowdsourced in the United States. We show that our policy significantly outperforms the leading algorithms that were previously proposed as part of an open algorithmic challenge. Further, we show how to extend our approach to an incremental learning setting, where the policy is capable of improving and adapting as new data is being collected over time.
A fuzzy modeling approach to decision fusion under uncertainty

A multi-sensor decision fusion scheme is presented in which the probabilities associated with the local sensor decisions are known to vary in a nonrandom fashion around their design values. The uncertainties associated with the local decisions are modeled by means of fuzzy sets. A Bayesian approach is used to design the optimum fusion rule for the case where the local sensor decisions are statistically independent across the sensors. In order to reach a crisp decision, the global Bayesian risk is defuzzified using a criterion for mapping fuzzy sets on to the real line. The performance of the optimum fusion rule obtained is illustrated by means of a numerical example.
Correlators of Special States in c=1 Liouville Theory

We generalize the ground ring structure to all other special BRST-invariant operators in the right branch in the c = 1 Liouville theory. We also discuss correlation functions of special states on the sphere.
Strong-Field Saturation Effects in Laser Media

Using Lamb's model, we analyze the effects of gain saturation by strong traveling-wave fields in dilute laser media. Using approximate solutions of an integral equation for the population inversion density (PID), the index of refraction and incremental gain are studied for arbitrarily strong fields. Effects of atomic motion are included for a Maxwellian velocity distribution, but pressure effects are neglected. The case of a monochromatic field leads to the saturation results of Gordon, White, and Rigden, which are studied as a function of frequency. For a small ratio of natural to Doppler linewidths, there is a transition from inhomogeneous to homogeneous broadening for sufficiently strong fields. An effect of particular interest is the generation of waves at $2{\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}$, $2{\ensuremath{\omega}}_{2}\ensuremath{-}{\ensuremath{\omega}}_{1}$, and higher order sidebands by two strong input signals at ${\ensuremath{\omega}}_{1}$ and ${\ensuremath{\omega}}_{2}$. The source of the parametric gain at these frequencies is the time-dependent gain saturation due to the presence of multiple strong fields. For ${\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}$ small compared to the decay rates ${\ensuremath{\gamma}}_{a}$ and ${\ensuremath{\gamma}}_{b}$ of the laser levels, the gain at these intermodulation sidebands is computed as a function of the field strengths. The limiting cases of homogeneous and inhomogeneous (due to atomic motion) broadening are studied in detail. These two cases give essentially the same results, for a given unsaturated gain. Numerical results indicate that a first-order side-band intensity at least 10% as large as that of the inducing fields can be easily observed in practice. The integral equation for the PID is converted into an infinite set of linear algebraic equations for a typical solid-state laser. The conditions under which this set of equations can be limited to a finite number is discussed, and the dependence of the sideband gain on ${\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}$ is calculated. For large ${\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}$, the gain at the $m\mathrm{th}$ sideband decreases as ${({\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2})}^{\ensuremath{-}m}$.
IIB or not IIB

We consider Type IIB superstring theory with the addition of n 9-branes and n anti-9-branes (and no orientifolds). The result is a ten-dimensional chiral theory of open and closed oriented strings with gauge group U(n) ? U(n). There is, however, a tachyonic instability which can be understood as the consequence of brane-antibrane annihilation. We therefore expect to recover the usual IIB theory as the tachyon rolls to infinity.