cssi/SciSciGPT-SciSciNet huggingface dataset:
Fuel Efficiency of Small Aircraft

There is a basic mismatch between the amount of power installed in small propeller-driven aircraft and that required for efficient cruising, which results from climb performance requirements. It is shown in this paper that there is a way of using excess power for most efficient cruise, the resulting airspeed coming closest to the Gabrielli-von Karman limit line of vehicular performance. A survey of 111 light aircraft was conducted, and it is found that many are operated at this optimum, while many more are not. A figure of merit is developed that measures cruise performance. Rationale is presented that is directly applicable to design for cruise efficiency.
Robust speech recognition by integrating speech separation and hypothesis testing

Missing-data methods attempt to improve robust speech recognition by distinguishing between reliable and unreliable data in the time-frequency (T-F) domain. Such methods require a binary mask to label speech-dominant T-F regions of a noisy speech signal as reliable and the rest as unreliable. Current methods for computing the mask are based mainly on bottom-up cues such as harmonicity and produce labeling errors that degrade recognition performance. In this paper, we propose a two-stage recognition system that combines bottom-up and top-down cues in order to simultaneously improve both mask estimation and recognition accuracy. First, an n-best lattice consistent with a speech separation mask is generated. The lattice is then re-scored by expanding the mask using a model-based hypothesis test to determine the reliability of individual T-F units. Systematic evaluations of the proposed system show significant improvement in recognition performance compared to that using speech separation alone.
Big symplectic or orthogonal monodromy modulo l

Let k be a field not of characteristic two, and let Λ be a set consisting of almost all rational primes invertible in k. Suppose that we have a variety X/k and strictly compatible system {Ml→X:l∈Λ} of constructible Fl-sheaves. If the system is orthogonally or symplectically self-dual, then the geometric monodromy group of Ml is a subgroup of a corresponding isometry group Γl over Fl, and we say that it has big monodromy if it contains the derived subgroup DΓl. We prove a theorem that gives sufficient conditions for Ml to have big monodromy. We apply the theorem to explicit systems arising from the middle cohomology of families of hyperelliptic curves and elliptic surfaces to show that the monodromy is uniformly big as we vary l and the system. We also show how it leads to new results for the inverse Galois problem
A discovery tool at work: the unexpected properties of a two-carbon residue

Abstract We report the very easy preparation of novel peptides 6a–n as represented by CF3CH2( l )Phe( l )IleOtBu (6a), a prospective antitumor compound. Peptides such as 6a are directly obtained via standard chemistry from a novel class of amino acids, Nα-trifluoroethyl amino acids 4. In fact, unexpectedly, the Nα-1,1,1-trifluoroethyl substitution completely deactivates the α-nitrogen. That is, compounds 4 behave exactly like Nα-protected amino acids, and take part in standard peptide synthesis accordingly. Representative compounds 4a–c are prepared by reaction of commercial amino acid t-butyl esters 2a–c with 1 eq iodonium salt 1 in dichloromethane/water at 22°C in 1 h or less. The reaction is promoted by NaHCO3 (1.5 eq). The intermediate Nα-1,1,1-trifluoroethyl t-butyl esters 3a–c are hydrolyzed and separated from coproducts at the same time by treatment with aqueous HCl at 22°C. Evaporation of the acid extracts provides analytically pure 4a–c in 78–98% yields.
Flux-Transport Dynamos with Lorentz Force Feedback on Differential Rotation and Meridional Flow: Saturation Mechanism and Torsional Oscillations

In this paper we discuss a dynamic flux-transport dynamo model that includes the feedback of the induced magnetic field on differential rotation and meridional flow. We consider two different approaches for the feedback: mean field Lorentz force and quenching of transport coefficients such as turbulent viscosity and heat conductivity. We find that even strong feedback on the meridional flow does not change the character of the flux-transport dynamo significantly; however, it leads to a significant reduction of differential rotation. To a large degree independent of the dynamo parameters, the saturation takes place when the toroidal field at the base of the convection zone reaches between 1.2 and 1.5 T, and the energy converted into magnetic energy corresponds to about 0.1%-0.2% of the solar luminosity. The torsional oscillations produced through Lorentz force feedback on differential rotation show a dominant poleward propagating branch with the correct phase relation to the magnetic cycle. We show that incorporating enhanced surface cooling of the active region belt (as proposed by Spruit) leads to an equatorward propagating branch in good agreement with observations.
DESTINY: A model for integrated structural design

Abstract DESTINY integrates all stages of the structural design process into an unified framework. The architecture of DESTINY is influenced by earlier work on Blackboard systems. It consists of several Knowledge-Modules that communicate through a Blackboard and are controlled by an Inference Mechanism. The Blackboard consists of several levels that define the abstraction hierarchy of objects. The entities generate at various levels in the Blackboard are connected through relational links to form a solution to the structural design problem. The Knowledge-Modules form a hierarchy of three levels; these levels represent a plan for organizing the problem solving activities. The Inference Mechanism consists of an Agenda and a Monitor. The Monitor takes the task with the highest priority (the first element) in the Agenda and executes it.
The Phenomenology of Universal Extra Dimensions at Hadron Colliders

Theories with extra dimensions of inverse TeV size (or larger) predict a multitude of signals which can be searched for at present and future colliders. In this paper, we review the different phenomenological signatures of a particular class of models, universal extra dimensions, where all matter fields propagate in the bulk. Such models have interesting features, in particular Kaluza–Klein (KK) number conservation, which makes their phenomenology similar to that of supersymmetric theories. Thus, KK excitations of matter are produced in pairs, and decay to a lightest KK particle (LKP), which is stable and weakly interacting, and therefore will appear as missing energy in the detector (similar to a neutralino LSP). Adding gravitational interactions which can break KK number conservation greatly expands the class of possible signatures. Thus, if gravity is the primary cause for the decay of KK excitations of matter, the experimental signals at hadron colliders will be jets + missing energy, which is typical...
DETERMINING QUASAR BLACK HOLE MASS FUNCTIONS FROM THEIR BROAD EMISSION LINES: APPLICATION TO THE BRIGHT QUASAR SURVEY

We describe a Bayesian approach to estimating quasar black hole mass functions (BHMF) using the broad emission lines to estimate black hole mass. We show how using the broad-line mass estimates in combination with statistical techniques developed for luminosity function estimation (e.g., the 1/Va correction) leads to statistically biased results. We derive the likelihood function for the BHMF based on the broad-line mass estimates, and derive the posterior distribution for the BHMF, given the observed data. We develop our statistical approach for a flexible model where the BHMF is modeled as a mixture of Gaussian functions. Statistical inference is performed using Markov chain Monte Carlo (MCMC) methods, and we describe a Metropolis-Hastings algorithm to perform the MCMC. The MCMC simulates random draws from the probability distribution of the BHMF parameters, given the data, and we use a simulated data set to show how these random draws may be used to estimate the probability distribution for the BHMF. In addition, we show how the MCMC output may be used to estimate the probability distribution of any quantities derived from the BHMF, such as the peak in the space density of quasars. Our method has the advantage that it is able to constrain the BHMF even beyond the survey detection limits at the adopted confidence level, accounts for measurement errors and the intrinsic uncertainty in broad-line mass estimates, and provides a natural way of estimating the probability distribution of any quantities derived from the BHMF. We conclude by using our method to estimate the local active BHMF using the z < 0.5 Bright Quasar Survey sources. At z ~ 0.2, the quasar BHMF falls off approximately as a power law with slope ~2 for M BH 108 M ☉. Our analysis implies that at a given M BH, z < 0.5 broad-line quasars have a typical Eddington ratio of ~0.4 and a dispersion in Eddington ratio of 0.5 dex.
Fine Pointing Of The Solar Optical Telescope In The Space Shuttle Environment

Instruments requiring fine (i.e., sub-arcsecond) pointing, such as the Solar Optical Telescope (SOT), must be equipped with two-stage pointing devices, coarse and fine. Coarse pointing will be performed by a gimbal system, such as the Instrument Pointing System, while the image motion compensation (IMC) will provide fine pointing. This paper describes work performed on the SOT concept design that illustrates IMC as applied to SOT. The SOT control system was modeled in the frequency domain to evaluate performance, stability, and bandwidth requirements. The two requirements of the pointing control, i.e., the 2 arcsecond reproducibility and 0.03 arcsecond rms pointing jitter, can be satisfied by use of IMC at about 20 Hz bandwidth. The need for this high bandwidth is related to Shuttle-induced disturbances that arise primarily from man push-offs and vernier thruster firings. A block diagram of SOT model/stability analysis, schematic illustrations of the SOT pointing system, and a structural model summary are included.
Infinite Graphs in Systematic Biology, with an Application to the Species Problem

We argue that C. Darwin and more recently W. Hennig worked at times under the simplifying assumption of an eternal biosphere. So motivated, we explicitly consider the consequences which follow mathematically from this assumption, and the infinite graphs it leads to. This assumption admits certain clusters of organisms which have some ideal theoretical properties of species, shining some light onto the species problem. We prove a dualization of a law of T. A. Knight and C. Darwin, and sketch a decomposition result involving the internodons of D. Kornet, J. Metz and H. Schellinx. A further goal of this paper is to respond to B. Sturmfels’ question, “Can biology lead to new theorems?”
Catalytic enantioselective synthesis of quaternary carbon stereocentres

Quaternary carbon stereocentres-carbon atoms to which four distinct carbon substituents are attached-are common features of molecules found in nature. However, before recent advances in chemical catalysis, there were few methods of constructing single stereoisomers of this important structural motif. Here we discuss the many catalytic enantioselective reactions developed during the past decade for the synthesis of single stereoisomers of such organic molecules. This progress now makes it possible to incorporate quaternary stereocentres selectively in many organic molecules that are useful in medicine, agriculture and potentially other areas such as flavouring, fragrances and materials.
Wavelets and WMAP non-Gaussianity

We study the statistical properties of the first-year Wilkinson Microwave Anisotropy Probe (WMAP) data on different scales using the spherical Mexican hat wavelet transform. Consistent with the 2004 results of Vielva et al., we find a deviation from Gaussianity in the form of kurtosis of wavelet coefficients on 3-4 scales in the southern Galactic hemisphere. This paper extends the work of Vielva et al. as follows: We find that the non-Gaussian signal shows up more strongly in the form of a larger than expected number of cold pixels and also in the form of scale-scale correlations among wavelet coefficients. We establish the robustness of the non-Gaussian signal under more wide-ranging assumptions regarding the Galactic mask applied to the data and the noise statistics. This signal is unlikely to be due to the usual quadratic term parameterized by the nonlinearity parameter fNL. We use the skewness of the spherical Mexican hat wavelet coefficients to constrain fNL with the first-year WMAP data. Our results constrain fNL to be 50+/-80 at 68% confidence and less than 280 at 99% confidence.
Metastatic cells will take any help they can get.

Two recent papers in Cancer Cell (Lu et al., this issue of Cancer Cell, and Kang et al.) illustrate means whereby acquisition of VCAM-1 by tumor cells can promote metastasis. First, monocyte/macrophages expressing α4 integrin bind VCAM-1 and provide survival signals enhancing establishment of metastases. Second, VCAM-1 allows dormant tumor cells to interact with osteoclasts, yielding paracrine signals and enhancing osteolytic metastatic growth.
Capital flows to Brazil in the nineties: Macroeconomic aspects and the effectiveness of capital controls

The resumption of capital flows to developing countries in the nineties is intertwined in the Brazilian case with the attempts to achieve inflation stabilization. A very restrictive monetary policy has, since the last Quarter of 1991, offered probably the world's highest yield to fixed income investments. The huge interest rate differential constituted the main determinant of capital inflows to Brazil. The magnitude of those flows exacerbated two main macroeconomic problems: an increase in the quasi-fiscal deficit due to the interest payments on the debt used to sterilize the inflows, and, after the Real Plan. also the overvaluation of the currency. The restrictions to capital inflows are described and analyzed, as well as the main "financial engineering" strategies used to circumvent the restrictions. Given the advanced stage of domestic financial markets-including a powerful derivatives market-the restrictions imposed have not been effective in preventing the inflows of foreign capital to invest in the high-yield-public debt. Given the small progress achieved so far in the fiscal side of the reforms, it is also doubtful that the capital inflows' restrictions have been effective in a broader sense, that of allowing the government to buy time to implement the essential structural reforms. By reducing the urgency of the politically costly structural reforms aimed at increasing domestic savings, capital inflows are believed to have detrimental incentive effects on the government's resolve to push forward the stabilization plan.
New precision measurements of free neutron beta decay with cold neutrons

Precision measurements in free neutron beta decay serve to determine the coupling constants of beta decay, and offer several stringent tests of the standard model. This study describes the free neutron beta decay program planned for the Fundamental Physics Beamline at the Spallation Neutron Source at Oak Ridge National Laboratory, and finally puts it into the context of other recent and planned measurements of neutron beta decay observables.
Radio Emission from Galaxies in the Hubble Deep Field

We report on sensitive radio observations made with the VLA at 8.5 GHz centered on the Hubble Deep Field (HDF). We collected data in the A, CnB, C, DnC, and D configurations corresponding to angular resolutions ranging from 03 to 10''. We detected 29 radio sources in a complete sample within 46 of the HDF center and above a flux density limit of 9.0 μJy (5 σ). Seven of these sources are located within the HDF itself, while the remaining 22 sources are covered by the Hubble flanking fields (HFFs) or ground-based optical images. All of the sources in the HDF are identified with galaxies with a mean magnitude R = 21.7, while the mean magnitude of the identifications outside the HDF is R = 22.1. One radio source in the HDF, which is just below our formal completeness level but is confirmed by independent 1.4 GHz observations, has no optical counterpart above the HDF limit of R = 29. Three radio sources outside the HDF have no optical counterparts to R = 27. Based on a radio and optical positional coincidence, we detected an additional 19 radio sources in this field (seven of which are contained in the HDF) with 6.3 μJy ≤Sν L*) galaxies at modest redshifts (0 z 1), many with evidence for recent star formation. The remainder are composed of a mixture of bright field elliptical galaxies and late-type galaxies with evidence of nuclear activity (LINERs and Seyfert galaxies) and nearby (z < 0.2) field spiral galaxies. None of the radio sources in this survey are identified with quasars or galactic stars.
A computer program which "understands"

This paper describes a computer program which demonstrates one approach to building an "intelligent" machine. The computer system called SIR---Semantic Information Retriever---exhibits some humanlike conversational behavior and appears to have certain cognitive abilities. The conversation presented in Figure 1 between a person (identified by "***.") and SIR illustrates some of the system's capabilities.
Improved synthesis and evaluation of 17-substituted aminoalkylgeldanamycin derivatives applicable to drug delivery systems

The 17-methoxy group of geldanamycin was substituted with 1,3-diaminopropane and 1,3-diamino-2-hydroxypropane to introduce a primary amino group useful for conjugation with targeting moieties and drug carriers. We have developed a procedure that has provided improved yield and reproducibility of the syntheses. Both geldanamycin derivatives demonstrated antiproliferative activity towards the human ovarian carcinoma cell line, A2780.
Electrochemical applications. How click chemistry brought biomimetic models to the next level: electrocatalysis under controlled rate of electron transfer.

This tutorial review discusses the immobilization of alkyne-terminated cytochrome c oxidase models on azide-functionalized self-assembled monolayers (SAM) coated gold electrodes that was made possible by click chemistry. The rate of electron delivery from the electrode to the model could be tuned by changing the nature of the SAM. Biologically relevant electron transfer rates (2–4 s−1) were obtained on slow SAMs allowing the model to turn over catalytically under steady-state conditions. Hence, click chemistry was a crucial tool to demonstrate, through electrocatalytic studies: (1) the role played by several features present in the distal side of the model, such as the CuB–Tyr244 pair, the distal pocket, and the stabilizing role of a distal water cluster; (2) the reversible inhibition of O2 reduction by H2S.
Distributive justice and optimal taxation of wages and interest in a growing economy

Abstract This paper studies the problem of the optimal mix of linear taxes on wages and on interest in a dynamic maximin economy in which workers differ according to their abilities and in which the distortionary impact of taxation falls on the quantity of investment in education. Conditions are derived for which the optimal interest tax is one hundred percent. It is shown that only in such economies is the taxable capacity with respect to both taxes utilized. Finally, the validity of the Golden Rule is reestablished.
The Cooling Flow to Accretion Flow Transition

Cooling flows in galaxy clusters and isolated elliptical galaxies are a source of mass for fueling accretion onto a central supermassive black hole. We calculate the dynamics of accreting matter in the combined gravitational potential of a host galaxy and a central black hole assuming a steady state, spherically symmetric flow (i.e., no angular momentum). The global dynamics depends primarily on the accretion rate. For large accretion rates no simple, smooth transition between a cooling flow and an accretion flow is possible; the gas cools toward zero temperature just inside its sonic radius, which lies well outside the region where the gravitational influence of the central black hole is important. For accretion rates below a critical value, however, the accreting gas evolves smoothly from a radiatively driven cooling flow at large radii to a nearly adiabatic (Bondi) flow at small radii. We argue that this is the relevant parameter regime for most observed cooling flows. The transition from the cooling flow to the accretion flow should be observable in M87 with the Chandra X-Ray Observatory.
Memory requirements for balanced computer architectures

One particular result is that to balance an array of p linearly connected PEs for performing matrix computations such as matrix multiplication and matrix triangularization, the size of each PE's local memory must grow linearly with p. Thus, the larger the array is, the larger each PE's local memory must be.
Measuring accurate transit parameters

By observing the transits of exoplanets, one may determine many fundamental sys- tem parameters. I review current techniques and results for the parameters that can be measured with the greatest precision, specifically, the transit times, the planetary mass and radius, and the projected spin-orbit angle.
A model for calculating conformational energies in pentacoordinate phosphorus compounds

Abstract A model is developed which allows the estimation of the relative stability of all trigonal bipyramidal (TP) and square pyramidal (SP) isomers of a given pentacoordinate phosphorus compound. It is based on the widely used pseudorotational hypothesis. The model makes use of activational energies governing fluxional behavior for simple acyclic derivatives of known structure and results of theoretical and spectroscopic studies defining TP-SP energy differences. Based on these criteria, apicophilicity scales are constructed for the TP and SP with the additional constraints that they have the same range and correlate linearly with each other as a function of ligand electronegativity. The resultant model which incorporates ring strain and steric terms has general applicability and should prove of considerable predictive value in quantifying pentacoordinate intermediates and transition states postulated in phosphorus reaction mechanisms. The model gives relative isomer energies in excellent agreement wit...
Effects of Market Segmentation and Bank Concentration on Mutual Fund Expenses and Returns: Evidence from Finland

A tremendous amount of research examines US mutual funds, but fund markets also thrive in other countries. However, research about these fast growing markets is lacking. This study addresses Finnish funds. Fast growth of the Finnish fund industry, strong bank dominance in the industry and recent EU membership make it an interesting market to examine. The Finnish fund market is also of particular interest since it had the fastest growth among the EU countries during 1996–2000. We find evidence that bank-managed and older funds charge higher expenses but investors are not compensated for paying higher expenses with higher risk-adjusted returns, suggesting a potential agency problem. Overall, Finnish fund expenses have decreased over time, consistent with EU membership reducing market segmentation and generating competition.
Ion density deviations in polyelectrolyte microcapsules: influence on biosensors

Polyelectrolyte microcapsules loaded with fluorescent dyes have been proposed as biosensors to monitor local pH and ionic strength for diagnostic purposes. In the case of charged microcapsules, however, the local electric field can cause deviations of ion densities inside the cavities, potentially resulting in misdiagnosis of some diseases. Using nonlinear Poisson–Boltzmann theory, we systematically investigate these deviations induced by charged microcapsules. Our results show that the microcapsule charge density, as well as the capsule and salt concentrations, contribute to deviations of local ion concentrations and pH. Our findings are relevant for applications of polyelectrolyte microcapsules with encapsulated ion-sensitive dyes as biosensors.
Geometric properties and related results for holomorphic Segre preserving maps

In this article, we examine holomorphic Segre preserving maps between the complexifications of real analytic hypersurfaces in ℂ n+1. In particular, we find several sufficient conditions ensuring that Segre transversality and total Segre nondegeneracy of the maps must hold.
A note on 'hot spot' hunting in deep-inelastic scattering

We consider the inclusive cross section for jet production with large transverse momentum in deep-inelastic scattering. This process has been proposed as a probe of small-x physics, particularly the measurement of 'hot spots' inside the proton. We present a numerical calculation of this process, taking into account a larger phase space. The theoretical reliability, as well as phenomenological uncertainties in the calculation, are discussed.
Discretionary accounting and the behavior of Japanese banks under financial duress

Abstract This paper investigates utilization of discretionary accounting practices in the context of international bank regulation under the Basle Accord. Specifically, we explore implications of earnings management as a means of regulatory-capital arbitrage by Japanese banks during a period of financial duress, 1989–1996. Using a sample of 607 pooled time series and cross-sectional observations, we find evidence that Japanese banks’ lending was capital constrained, and that banks set gains on securities sales and loan-loss provisions in such a way as to smooth reported income and replenish regulatory capital. Our results support the hypothesis that the form of earnings management examined may have been instrumental in enabling some Japanese banks to comply with international capital regulation. We contend that this behavior is otherwise inexplicable on the basis of significant informational, tax or economic motivations.
Molecular Line Emission from Gravitationally Unstable Protoplanetary Disks

In the era of high-resolution submillimeter interferometers, it will soon be possible to observe the neutral circumstellar medium directly involved in gas giant planet (GGP) formation at physical scales previously unattainable. In order to explore possible signatures of GGP formation via disk instabilities, we have combined a three-dimensional (3D), nonlocal thermodynamic equilibrium (LTE) radiative transfer code with a 3D, finite differences hydrodynamical code to model molecular emission lines from the vicinity of a 1.4MJ self-gravitating proto-GGP. Here we explore the properties of rotational transitions of the commonly observed dense gas tracer, HCO+. Our main results are as follows: (1) Very high lying HCO+ transitions (e.g., HCO+ J = 7-6) can trace dense clumps around circumstellar disks. Depending on the molecular abundance, the proto-GGP may be directly imageable by the Atacama Large Millimeter Array (ALMA). (2) HCO+ emission lines are heavily self-absorbed through the proto-GGP's dense molecular core. This signature is nearly ubiquitous and only weakly dependent on assumed HCO+ abundances. The self-absorption features are most pronounced at higher angular resolutions. Dense clumps that are not self-gravitating only show minor self-absorption features. (3) Line temperatures are highest through the proto-GGP at all assumed abundances and inclination angles. Conversely, due to self-absorption in the line, the velocity-integrated intensity may not be. High angular resolution interferometers such as the Submillimeter Array (SMA) and ALMA may be able to differentiate between competing theories of GGP formation.
Optimal research for cournot oligopolists

We extend the classical Cournot model to take account of uncertainty in either the cost function or the demand function. By undertaking research, firms can acquire private (asymmetric) information to help resolve their uncertainty and make a more informed production decision. The model is a two stage game: in the first stage research levels are chosen, and in the second stage, conditional on private research outcomes, production decisions are made. We find that for a linear, continuous information structure there is a unique Nash equilibrium to the game. In the equilibrium there may be an inefficient amount of aggregate research and there may be incomplete pooling as well. The model specializes to the classical case when the cost of research is zero (and each firm gains essentially the same information by doing an infinite amount of research) or when the cost of research is so high no firm undertakes research.
Self-assembling DNA graphs

It has been shown theoretically that three dimensional graph structure and DNA self-assembly can be used to solve numerous computational problems such as 3-SAT and 3-colorability in a constant number of laboratory steps. In this assembly, junction molecules and duplex DNA molecules are the basic building blocks. This paper presents experimental results of DNA self-assembly of non regular graphs using junction molecules as vertices and duplex DNA molecules as edge connections.
1-Overlap cycles for Steiner triple systems

A number of applications of Steiner triple systems (e.g. disk erasure codes) exist that require a special ordering of its blocks. Universal cycles, introduced by Chung, Diaconis, and Graham in 1992, and Gray codes are examples of listing elements of a combinatorial family in a specific manner, and Godbole invented the following generalization of these in 2010. 1-overlap cycles require a set of strings to be ordered so that the last letter of one string is the first letter of the next. In this paper, we prove the existence of 1-overlap cycles for automorphism free Steiner triple systems of each possible order. Since Steiner triple systems have the property that each block can be represented uniquely by a pair of points, these 1-overlap cycles can be compressed by omitting non-overlap points to produce rank two universal cycles on such designs, expanding on the results of Dewar.
From here to criticality: renormalization group flow between two conformal field theories

Abstract Using non-perturbative techniques, we study the renormalization group trajectory between two conformal field theories. Specifically, we investigate a perturbation of the A 3 superconformal minimal model such that in the infrared limit the theory flows to the A 2 model. The correlation functions in the topological sector of the theory are computed numerically along the trajectory, and these results are compared to the expected asymptotic behavior. Excellent agreement is found, and the characteristic features of the infrared theory, including the central charge and the normalized operator product expansion coefficients, are obtained. We also review and discuss some aspects of the geometrical description of N = 2 supersymmetric quantum field theories recently uncovered by Cecotti and Vafa.
Four-Dimensional String/String Duality

We present supersymmetric soliton solutions of the four-dimensional heterotic string corresponding to monopoles, strings and domain walls. These solutions admit the D = 10 interpretation of a fivebrane wrapped around 5, 4 or 3 of the 6 toroidally compactified dimensions and are arguably exact to all orders in α′. The solitonic string solution exhibits an SL(2, Z) strong/weak coupling duality which however corresponds to an SL(2, Z) target space duality of the fundamental string.
Use of 13C NMR spectrometric data to produce a predictive model of estrogen receptor binding activity.

We have developed a spectroscopic data−activity relationship (SDAR) model based on 13C NMR spectral data for 30 estrogenic chemicals whose relative binding affinities (RBA) are available for the alpha (ERα) and beta (ERβ) estrogen receptors. The SDAR models segregated the 30 compounds into strong and medium binding affinities. The SDAR model gave a leave-one-out (LOO) cross-validation of 90%. Two compounds that were classified incorrectly in the SDAR model were in the transition zone between classifications. Real and predicted 13C NMR chemical shifts were used with test compounds to evaluate the predictive behavior of the SDAR model. The 13C NMR SDAR model using predicted 13C NMR data for the test compounds provides a rapid, reliable, and simple way to screen whether a compound binds to the estrogen receptors.
The cerium mediated conversion of esters to allylsilanes

Abstract Reaction of esters with the reagent prepared from CeCl 3 and TMSCH 2 MgCl in THF, followed by deoxysilylation on silica gel, effects efficient conversion to allylsilanes. Methyl 1-adamantane carboxylate, a sterically hindered ester, does not react under these conditions.
Site- and enantioselective formation of allene-bearing tertiary or quaternary carbon stereogenic centers through NHC-Cu-catalyzed allylic substitution.

Catalytic enantioselective allylic substitutions that result in addition of an allenyl group ( 98% SN2′ selectivity, and 99:1 enantiomeric ratio (er). Site-selective NHC–Cu-catalyzed hydroboration of enantiomerically enriched allenes and conversion to the corresponding β-vinyl ketones demonstrates the method's utility.
Inferring the Nutrient Content of Food With Prior Information

Given measurements on the nutrient content of the U.S. food supply and a coherent reduced form empirical model of the demand for foods, we can analyze the effect of agricultural farm and food policy on nutrition. Using unpublished documents from the HNIS, estimates of the percentages of seventeen nutrients supplied by twenty-one foods were compiled for the period 1952-1983. The Bayesian Method of Moments is applied to this data set to obtain a proper prior for the purpose of drawing year-to-year inferences about the nutrient content of the U.S. food supply for the period 1909-1994. Information theory and the Kullback-Leibler cross entropy criterion are used to formalize the inference problem. (This abstract was borrowed from another version of this item.)
EFFECTIVE STAR FORMATION RATES FOR COSMOLOGICAL APPLICATIONS

Effective star formation rates in tabular form are computed that yield a prescription for the star formation activity in model galaxies as a function of ambient density, metallicity, and stellar feedback. The effects of supernova explosions on the thermal balance of the interstellar medium (ISM) and the presence of a multiphase ISM are explicitly included. The resulting grid of models can be implemented easily in N-body codes for the computation of star formation processes in merging galaxies and cosmological simulations.
A novel reagent for labelling macromolecules with intensely luminescent lanthanide complexes

Abstract A novel bifunctional chelator, 4-iodoacetamidodipicolinicacid, has been synthesized in three steps starting with chelidamic acid, and used to prepare protein conjugates that form stable and intensely luminescent complexes with Tb(III) and Eu(III). The excited state lifetime of Tb(III) complexes with this reagent was 1.25 ms, permitting its use for ultrasensitive time-resolved luminescence assays.
SYSTEMATIC UNCERTAINTIES IN STELLAR MASS ESTIMATION FOR DISTINCT GALAXY POPULATIONS

We show that different stellar mass estimation methods yield overall mass scales that disagree by factors up to ~2 for the z = 0 galaxy population and, more importantly, relative mass scales that sometimes disagree by factors 3 between distinct classes of galaxies (spiral/irregular types, classical E/S0s, and E/S0s whose colors reflect recent star formation). This comparison considers stellar mass estimates based on (1) two different calibrations of the correlation between K-band mass-to-light ratio and B - R color and (2) detailed fitting of UBRJHK photometry and optical spectrophotometry using two different population synthesis models (Bruzual-Charlot and Maraston), with the same initial mass function in all cases. We also compare stellar+gas masses with dynamical masses. This analysis offers only weak arguments for preferring a particular stellar mass estimation method, given the plausibility of real variations in dynamical properties and dark matter content. These results help to calibrate the systematic uncertainties inherent in mass-based evolutionary studies of galaxies, including comparisons of low- and high-redshift galaxies.
Yet another Vs equation

The classical Raymer-Hunt-Gardner functional form Vp = (1−ϕ)2 VpS +ϕ VpF , where VpS and VpF denote the P -wave velocity in the solid and pore-fluid phases, respectively, and ϕ is the total porosity, can also be used to relate the S-wave velocity in dry rock to porosity and mineralogy as VsDry = (1−ϕ)2 VsS , where VsS is the S-wave velocity in the solid phase. Assuming that the shear modulus of rock does not depend on the pore fluid, Vs in wet rock is VsWet = VsDry ρbDry ∕ ρbWet , where ρbDry and ρbWet denote the bulk density of the dry and wet rock, respectively. This new functional form for Vs prediction reiterates Nur’s critical porosity concept: The Vp ∕ Vs ratio in dry rock equals that in the solid phase. It accurately predicts Vs in consolidated clastic and carbonate rock. Two motivations for using it are (1) it is simple, and (2) it predicts Vs not from Vp but directly from ϕ and mineralogy.
‘Fluorine dance’ on the fullerene surface

Abstract A facile fluorine migration process (‘fluorine dance’) leads to the formation of the most thermodynamically stable isomers during the high temperature fluorination of [60]fullerene.
2,2′,7,7′‐Tetrahydroxy‐1,1′‐Binaphthyl: A Versatile Chiral Spacer for Monotopic and Ditopic Cyclophane Hosts with Apolar Binding Sites

Derivatives of 2,2′,7,7′-tetrahydroxy-1,1′-binaphthyl (5) are synthetically readily available chiral shapes with a major and a minor groove. Previous work by Cram et al. has shown that efficient chiral crown ether binding sites can be constructed at the binaphthyl minor groove. The major groove is almost twice as wide and possesses suitable dimensions to shape flat apolar binding sites in chiral cyclophane hosts. The eight-step syntheses of the two novel cyclophanes 6 and 7 are described. The apolar cavities of these hosts are formed by bridging with two linear four-carbon chains the 7,7′-oxygens at the major groove of 5 to the two phenolic oxygens of a 4,4-bis(4-hydroxy-3,5-dimethylphenyl)piperidine unit. 1H NMR complexation studies show that 1:1 complexes of 6 and 7 with 6-methoxy-2-naphthonitrile and other naphthalene derivatives in aqueous methanol are as stable as the previously reported complexes of bis(diphenylmethane)-hosts. The different solvation characteristics of cation and apolar binding are demonstrated with the ditopic host 7. In addition to the apolar binding site at the major groove, 7 also possesses a crown ether binding site at the minor groove of the binaphthyl spacer. By changing the methanol content of a water-methanol mixture, this host can be switched from an efficient binder of neutral naphthalene guests to a good host for potassium cations. The activities of the two binding sites in 7 are almost entirely independent of each other; consequently, the binding of a naphthalene guest in the 1:1:1 (host-naphthalene-K+) complex is nearly as strong as in the 1:1 complex. The methyl ester of (S)-naproxen forms stable complexes with the racemic hosts 6 and 7. The 1H NMR spectra of these complexes show considerably different shifts for the aromatic resonances of the host enantiomers. These differences indicate the formation of diastereomeric complexes of different geometries or stabilities.
Large branes in AdS and their field theory dual

Recently it was suggested that a graviton in AdS5 ? S5 with a large momentum along the sphere can blow up into a spherical D-brane in S5. In this paper we show that the same graviton can also blow up into a spherical D-brane in AdS5 with exactly the same quantum numbers (angular momentum and energy). These branes are BPS, preserving 16 of the 32 supersymmetries. We show that there is a BPS classical solution for SYM on S3 ? R with exactly the same quantum numbers. The solution has non-vanishing Higgs expectation values and hence is dual to the large brane in AdS.
The Place of the Soft Budget Constraint Syndrome in Economic Theory

Abstract The concept of the budget constraint, previously applied mainly to household decisions, was extended to enterprises and other organizations initially by Kornai for socialist economies. The more general phenomenon usually includes rent seeking, although not all rent-seeking behavior is associated with a soft budget constraint (SBC). Rather, SBC analysis is a theory of exit, or more precisely, of the demise of organizations. Moreover, the syndrome cannot be treated as a special case of the theory of regulation because not all price regulation softens the budget constraint. The SBC can emerge in nonregulated spheres, especially when financial interactions take place in vertical relationships between superiors and subordinates rather than in horizontal market conditions.J. Comp. Econom.,March 1998, 26(1), pp. 11–17. Littauer Center, Harvard University, Cambridge, Massachusetts 02138, and Collegium Budapest, Budapest, Hungary.
The anthropic argument against infinite past and the Eddington-Lemaitre universe

This study in the philosophy of cosmology is a part of an ongoing effort to investigate and reassess the importance of the anthropic (Davies-Tipler) argument against cosmologies containing the past temporal infinity. Obviously the prime targets of this argument are cosmological models stationary on sufficiently large scale, the classical steady state model of Bondi, Gold and Hoyle being the best example. Here we investigate the extension of application of this argument to infinitely old non-stationary models and discuss additional constraints necessary to be imposed on such models for the edge of the anthropic argument to be preserved. An illustrative counterexample is the classical Eddington-Lemaitre model, in the analysis of which major such constraints are presented. Consequences of such an approach for our understanding of the nature of time are briefly discussed.
Financial Intermediation and Endogenous Growth

An endogenous growth model with multiple assets is developed. Agents who face random future liquidity needs accumulate capital and a liquid, but unproductive asset. The effects of introducing financial intermediation into this environment are considered. Conditions are provided under which the introduction of intermediaries shifts the composition of savings toward capital, causing intermediation to be growth promoting. In addition, intermediaries generally reduce socially unnecessary capital liquidation, again tending to promote growth.
Surface coordination chemistry of noble-metal electrocatalysts: Oxidative addition and reductive elimination of iodide at iridium, platinum and gold in aqueous solutions

Abstract The oxidative addition and reductive elimination of the iodo ligand has been compared at smooth polycrystalline gold, platinum and iridium surfaces in aqueous solutions. On these three metals, the iodo species undergoes spontaneous oxidative chemisorption to form a close-packed monolayer of zero-valent iodine, the saturation coverage of which is limited by the van der Waals radius of the iodine atom; this oxidative addition process is further manifested by evolution of hydrogen gas from proton reduction. Elimination of iodine from these surfaces can be achieved by its reduction back to the anion either by application of sufficiently negative potentials or by exposure to ample amounts of hydrogen gas. On Pt and Ir, the reductive desorption of iodine is coupled with reductive chemisorption of hydrogen; consequently, the reaction is a two-electron, pH-dependent process. A plot of E 1/2 , the potential at which the iodine coverage is decreased to half its maximum value, against pH yields information concerning the redox potential of the I (ads) /I − (ads) couple in the surface-coordinated state. On Au, where dissociative chemisorption of hydrogen does not occur, the iodine-stripping process is a pH-independent, one-electron reaction. The difference in the redox potentials [ E o I(ads) - E o I(aq ] for the I (ads) and I 2(aq) /I − (aq) redox couples was found to be −0.90 V on Au, − 0.76 V on Pt, and −0.72 V on Ir. These values imply that the ratio of the formation constants for surface coordination of the iodine and iodide species ( K f,I / K f,I− ) is 2 × 10 28 on Au, 1 × 10 26 on Pt, and 2 × 10 25 on Ir.
On Stellar Dynamo Processes and Differential Rotation

Many stars exhibit strong magnetic fields, some of which are thought to be of primordial origin and others a sign of magnetic dynamo processes. We briefly review the results of observational studies of solar-type stars seeking to evaluate the linkage between rotation rate and possible magnetic cycles of activity. Clearly turbulent convection and rotation within spherical shell geometries provide ingredients essential for dynamo action. However, intensive efforts over several decades in solar research have demonstrated that it is no easy matter to achieve cyclic magnetic activity that is in accord with observations. Helioseismology has revealed that an essential element for the global solar dynamo is the presence of a tachocline of shear at the base of the solar convection zone, leading to the likely operation of an interface dynamo. We review the crucial elements for achieving a cyclic magnetic activity. We then discuss some of our current 3-D MHD simulations of solar turbulent convection in spherical shells that yield differential rotation profiles which make good contact with some of the helioseismic findings. We show that such turbulent motions can amplify and sustain magnetic field in the bulk of the convective zone whose strength are sufficient to feed back both upon the convection and its global circulations.
A Photometric and Spectroscopic Study of the Cataclysmic Variable ST LMi during 2005-2006* **

We present orbit-resolved spectroscopic and photometric observations of the polar ST LMi during its recent low and high states. In the low-state spectra, we report the presence of blue and red satellites in the Hα emission line; the velocities and visibility of the satellites vary with phase. This behavior is similar to emission-line profile variations recently reported in the low state of AM Her, which were interpreted as being due to magnetically confined gas motions in large loops near the secondary. Our low-state spectroscopy of ST LMi is discussed in terms of extreme chromospheric activity on the secondary star. Concurrent photometry indicates that occasional low-level accretion may be present, as well as cool regions on the secondary near the inner Lagrangian point, L1. Furthermore, we report a new "extreme low state" of the system at V ~ 18.5 mag. Our orbital high-state spectroscopy reveals changes in the emission-line profiles with orbital phases that are similar to those reported by earlier high-state studies. The complicated emission-line profiles generally consist of two main components. The first has radial velocity variations identical to that of the major emission Hα component seen in the low state. The second is an additional redshifted component appearing at the phases of maximum visibility of the accreting column of the white dwarf; it is interpreted as being due to infall velocities on the accreting magnetic pole of the white dwarf. At the opposite phases, an extended blue emission wing appears on the emission-line profiles. We confirm the presence of a broad absorption feature near 6275 A, which has been previously identified as a Zeeman σ- absorption component of Hα. This feature appears at just those phases when the accretion pole region is most directly visible and most nearly face-on to the observer.