cssi/SciSciGPT-SciSciNet huggingface dataset:
The copper(II) complexes of 1-allyl-3-(o-, m- and p-carboxyphenyl)-2-thiourea

Abstract The copper(II) complexes of 1-allyl-3-(2-, 3- and 4-carboxyphenyl)-2-thiourea have been isolated and characterized by elemental analysis, infrared, EPR, and UV-Vis studies. The ortho and para ligands form complexes of stoichiometry CuL 2 while the meta ligand forms complexes of stoichiometry CuL and CuL 4 . All ligands form additional bridges resulting in polymeric solid-state structures. The ortho ligands coordinate to the metal through a carboxylate oxygen and the aryl nitrogen to form a tetrahedrally- distorted tetragonal geometry about the copper, whereas the para ligands coordinate only through the aryl nitrogen atom, with the remaining cooper coordination sites being occupied by two water molecules. In the 1:1 meta complex the carboxylate binds as a unidentate ligand to the copper, while the 1:4 meta complex has a tetragonally-elongated octahedral copper geometry with coordination by four nitrogen atoms from four different ligands.
Bounds on Operator Dimensions in 2D Conformal Field Theories

We extend the work of Hellerman [1] to derive an upper bound on the conformal dimension Δ2 of the next-to-lowest nontrival primary operator in unitary, modular-invariant two-dimensional conformal field theories without chiral primary operators, with total central charge c tot > 2. The bound we find is of the same form as found by Hellerman for ∆1: ∆2 ≤ $ \frac{{{c_{\mathrm{tot}}}}}{12 } $ + O(1). We obtain a similar bound on the conformal dimension Δ3, and present a method for deriving bounds on Δ n for any n, under slightly modified assumptions. For asymptotically large c tot and n ≲ exp(πc/12), we show that ∆ n ≤ $ \frac{{{c_{\mathrm{tot}}}}}{12 } $ + O(1). This implies an asymptotic lower bound of order exp(πc tot /12) on the number of primary operators of dimension ≤ c tot /12 + O(1), in the large-c limit. In dual gravitational theories, this corresponds to a lower bound in the flat-space limit on the number of gravitational states without boundary excitations, of mass less than or equal to 1/4G N .
RECURRENT AND PERIODIC POINTS IN DENDRITIC JULIA SETS

We relate periodic and recurrent points in dendritic Julia sets. This generalizes well-known results for interval dynamics.
Lag structures in commodity advertising research

This article examines basic assumptions about the lag structure of advertising. Evidence suggests for frequently consumed commodities, the lag structure is probably a monotonic decreasing function. Confusion may exist over what advertising variables to analyze and what shape the lag structure should take. Cumulative structures need to be differentiated from decay structures.
Conversion of 2-alkylcinnamaldehydes to 2-alkylindanones via a catalytic intramolecular Friedel-Crafts reaction.

The preparation of indanones by the intramolecular acylation of 3-arylpropanoic acids or halides requires the use of noncatalytic acid promoters. In the presence of 5−10 mol % FeCl3, in situ generated dimethyl acetals of (E)-2-alkylcinnamaldehydes cyclize to 1-methoxy-2-alkyl-1H-indenes in good-to-high yields. The 1-methoxyindenes were converted in high yield into 2-alkylindanones by treatment with triethylamine, to effect isomerization to the isomeric enol ethers, followed by acid-catalyzed hydrolysis. Thus, a catalytic, intramolecular Friedel−Crafts reaction leading to 2-alkylindanones from 2-alkylcinnamaldehydes was developed.
Microwave Dielectric Properties of Doped BaTi4O9

Polycrystalline BaTi4O9 doped with Mn, Sn, Zr, Ca, Sr, and Pb was prepared from carbonates and oxides. Single-phase ceramics with densities exceeding 97% of theoretical were made with up to 3 mol% Mn; 6 mol% Sn, Zr, and Ca; and 8 mol% Sr and Pb. Dielectric constant, k, quality factor, Q, and temperature coefficient of frequency, τf, of ∼37, 5675, and 15 ppm/°C, respectively, were determined at 4 GHz for undoped BaTi4O9. Doping did not significantly affect k and τf. However, doping with Mn, Sn, and Pb lowered Q, whereas doping with Zr, Ca, and Sr increased Q by up to 2000. Additions of 0.5 mol% MnO2 as a second phase improved Q from 3675 to 7600.
Gravitational wave astronomy: needle in a haystack.

A worldwide array of highly sensitive ground-based interferometers stands poised to usher in a new era in astronomy with the first direct detection of gravitational waves. The data from these instruments will provide a unique perspective on extreme astrophysical objects, such as neutron stars and black holes, and will allow us to test Einstein’s theory of gravity in the strong field, dynamical regime. To fully realize these goals, we need to solve some challenging problems in signal processing and inference, such as finding rare and weak signals that are buried in non-stationary and non-Gaussian instrument noise, dealing with high-dimensional model spaces, and locating what are often extremely tight concentrations of posterior mass within the prior volume. Gravitational wave detection using space-based detectors and pulsar timing arrays bring with them the additional challenge of having to isolate individual signals that overlap one another in both time and frequency. Promising solutions to these problems will be discussed, along with some of the challenges that remain.
[C5H14N2][(MoO3)3(SO4)]·H2O: Sulfated α-Molybdena Chains

Recent work in the preparation of organically templated metal sulfates under hydrothermal conditions has been extended to include the sulfation of α-molybdena through the synthesis of [C5H14N2][(MoO3)3(SO4)]·H2O. Single crystals were grown under hydrothermal conditions from molybdenum oxide, water, sulfuric acid, and an enantiomerically pure (R)-2-methylpiperazine source and characterized using both single-crystal X-ray diffraction and infrared spectroscopy. One-dimensional [(MoO3)3(SO4)]n2n- chains, based on a neutral α-molybdena backbone, are connected through an extensive hydrogen-bonding network containing [C5H14N2]2+ cations and occluded water molecules. The direction of the hydrogen bonding is primarily dictated by the nucleophilicity of the respective oxide ligands, as determined using bond valence sums.
Explaining Procyclical Fiscal Policy in African Countries

Simple time series regressions for 37 low-income African countries during 1960--2004 suggest that government consumption is highly procyclical, with consumption responding more than proportionately to fluctuations in output in many cases. The results from a cross-country specification suggest that government consumption is more procyclical in those African countries that are more reliant on foreign aid inflows and that are less corrupt, and that it is less procyclical in countries with unequal income distribution and that are more democratic. These results contrast with those from recent research using data sets that comprise a more diverse groups of countries in terms of geography and income levels. Copyright 2008 The author 2008. Published by Oxford University Press on behalf of the Centre for the Study of African Economies. All rights reserved. For permissions, please email: journals.permissions@oxfordjournals.org, Oxford University Press.
The Debate over El Lobo: Can Historians Make a Difference?

In February 2003, historians, wolf-experts, ranchers, environmental activists, and some two hundred members of the general public gathered in Las Cruces, New Mexico, to discuss the past, present, and future of the Mexican gray wolf. “Leopold Forum: El Lobo” explored the history of wolf extirpation in the early twentieth century and the recent contested effort to reintroduce wolves into the Southwest, under the Endangered Species Act. The program included keynote addresses by a historian, a wolf biologist, and a ranching spokesperson; a series of panel presentations; a dinner featuring an environmental activist as speaker; and a roundtable discussion. A private breakfast-discussion among the stakeholders, facilitated by a professional conflict negotiator, followed the conference. The article narrates the history of wolf extirpation and reintroduction, and describes the logistics of organizing the conference and its outcome.
Real-time game theoretic coordination of competitive mobility-on-demand systems

This paper considers competitive mobility-on-demand systems where a group of vehicle sharing companies provide pickup-delivery service in populated areas. The companies, on one hand, want to collectively regulate the traffic of the user queueing network, and on the other hand, aim to maximize their own net profit at each time instant. We formulate the strategic interconnection among the companies as a real-time game. We propose an algorithm to achieve vehicle balance and practical regulation of the user queueing network. We quantify the relation between the regulation error and the system parameters.
The Number of Permutations Realized By a Shift

A permutation $\pi$ is realized by the shift on $N$ symbols if there is an infinite word on an $N$-letter alphabet whose successive left shifts by one position are lexicographically in the same relative order as $\pi$. The set of realized permutations is closed under consecutive pattern containment. Permutations that cannot be realized are called forbidden patterns. It was shown in [J. M. Amigo, S. Elizalde, and M. B. Kennel, J. Combin. Theory Ser. A, 115 (2008), pp. 485-504] that the shortest forbidden patterns of the shift on $N$ symbols have length $N+2$. In this paper we give a characterization of the set of permutations that are realized by the shift on $N$ symbols, and we enumerate them according to their length.
Common Agency with Horizontally Differentiated Principals

I analyze a common agency relationship where the agent has private information about the difference in his value for two principals. When the principals independently offer incentive contracts, the agent specializes less than is socially efficient, but more than when they cooperate and choose the contract that maximizes their joint payoff. Under both arrangements the agent faces countervailing incentives. The pooling region of types receiving a flat fee is larger and the incentive pay of the remaining types is lower powered under cooperation than under independent contracting. The principals prefer independent contracting with a common agent to exclusive dealing.
A finite element analysis approach with integrated PID control for simultaneous precision positioning and vibration suppression of smart structures

This paper focuses on the development of an ANSYS finite element analysis (FEA) environment with integrated PID control scheme for simultaneous precision positioning and vibration suppression of smart composite structures with piezoelectric flat patches acting as actuators. This environment includes three modules: structural modeling, PID controller design, and dynamic analysis of smart structures. Two types of PID controllers are investigated, namely, PID vibration suppression (PID-VS) controller and PID simultaneous precision positioning and vibration suppression (PIDSPPVS) controller. The PID-VS controller is suitable to perform only vibration suppression with no positioning capability. The PID-SPPVS controller is equipped with SPPVS capabilities. The characteristics of individual control gains and their behavior with respect to each other for the two PID controllers are also studied. The gain selection for the PID-VS controller is based on obtaining the best VS while the gain selection for the PID-SPPVS controller is based on achieving the best positioning accuracy and VS simultaneously. In this study, a horizontal cantilevered graphite/epoxy composite beam with one surface-mounted ACX piezoelectric flat patch located at the beam root is first modeled. Next, the FE modal analysis is performed to determine the natural frequencies and hence the time step interval needed for the FE transient analysis. During the transient analysis, the mid-point of the beam tip is subjected to different types of external excitations such as sine loadings with different frequencies as well as random forces to evaluate the two PID controller performances. It is demonstrated that the FEA model with integrated PID-SPPVS controller is able to reach the desired position in a much shorter time in comparison to the PID-VS controller. Vibration amplitude reduction capabilities for the both PID controllers are very similar, although the PID-VS controller performs slightly better. This study also implies that the integrated FEA environment, consisting of the structural modeling of active composite structures with piezoelectric flat patches, modal and transient analyses, controller design, and simulation, provides a powerful tool for the design, analysis, and control of smart structures with SPPVS capabilities.
The Polanyi School of Anthropology on Money: An Economist's View

This paper questions the popular anthropological assumption that all purpose money rules in the West today. Contrary to the followers of Karl Polanyi in anthropology, modern as well as primitive money is special purpose money. It is argued further that serious difficulties and confusions arise from indiscriminate use of the term money to refer both to (1) media of exchange and means of payment and (2) units of account. Lastly, the scholarship and perspicacity of the Polanyist verdicts about economists' views in the area of money is disputed.
Empirical determinants of intertemporal choice

Abstract We provide new evidence on the empirical determinants of intertemporal financial decisions. We use an exogenously imposed choice affecting nearly all Croatian retirees to study characteristics associated with choosing a larger, deferred stream of payments over a smaller, more immediate payment. Individuals are more willing to defer if they have higher incomes and are not liquidity constrained, have a longer time horizon because of better health and longer life expectancy, and have stronger bequest motives. Individuals who expect currency devaluation or political risk to reduce the value of future income are more likely to take the earlier income stream.
Recent advances in ecosystem-atmosphere interactions: an ecological perspective.

The atmosphere and terrestrial ecosystems are fundamentally coupled on a variety of time–scales. On short time–scales, this bi–directional interaction is dominated by the rapid exchange of CO2, water and energy between the atmosphere and the land surface; on long time–scales, the interaction involves changes in ecosystem structure and composition in response to changes in climate that feed back through biophysical and biogeochemical mechanisms to influence climate over decades and centuries. After briefly describing some early pioneering work, I focus this review on recent advances in understanding long–term ecosystem–atmosphere interactions through a discussion of three case studies. I then examine how efforts to assess the stability and resilience of ecosystem–atmosphere interactions over these long time–scales using Dynamic Global Vegetation Models are hampered by the presence of important functional diversity and heterogeneity within plant communities. Recent work illustrates how this issue can be addressed through the use of Structured Ecosystem Models that more accurately scale between the short–term physiological responses of individual plants and the long–term, large–scale dynamics of heterogeneous, functionally diverse ecosystems.
On the existence of sunspot equilibria in an overlapping generations model

Abstract The existence of sunspot equilibria is shown in a one-commodity overlapping generations model without stationarity assumptions on preferences, endowments, or nominal taxes. The essential assumption is that there is a continuum of perfect foresight equilibria. The technique is also useful for constructing stationary sunspot equilibria when they exist. Consumption in a sunspot equilibrium is shown to lie within the range consistent with perfect foresight.
Rejection of Radio-Frequency Noise with a Wide-Band Differential Preamplifier and Solid-Shielded Coaxial Input Cables

Radio-frequency signals simulating electrical interference ranging from 50 Hz to 50 MHz were applied to the shields of the input cable system (two solid- shielded, mineral-insulated cables approximately 6 m long) of a wide-band (approximately 60 MHz) differential preamplifier for use with fission counters as input devices as part of in-vessel, low-level flux monitors in future liquid- metal fast breeder reactors (LMFBRs) to determine the common-mode rejection. Results show that differences in electrical properties and shielding characteristics of the two input coaxial cables along with end effects produced by an unbalanced sensor severely degrade the rejection capability of the differential preamplifier. At 1 MHz, the common-mode rejection without input cables is approximately -70 dB; this is reduced to approximately -10 dB when measured with the rf signal applied to the surface of the input cable shields. Measurements of the shielding characteristics of the input cables showed resonances at test frequencies greater than 2 MHz. A ferrite core was installed in the input assembly to increase the impedance of the shields and to permit termination of the coaxial line consisting of the input cable shields and the protective metal conduit for the input cables. This assembly eliminated all resonances below 20more » MHz. The increased impedance also reduced the amplitude of the shield currents, resulting in an increase in the shielding effectiveness of the input cables without affecting the signal transmission of the cables. (auth)« less
Detection of the Meissner effect with a diamond magnetometer

We examine the possibility of probing superconductivity effects in metal nanoclusters via diamond magnetometry. Metal nanoclusters have been proposed as constitutive elements of high-Tc superconducting nanostructured materials. Magnetometry based on the detection of spin-selective fluorescence of nitrogen-vacancy (NV) centers in diamond is capable of nanoscale spatial resolution and can be used as a tool for investigating the properties of single or multiple clusters interacting among each other or with a surface. We have carried out sensitivity estimates and experiments to understand how these magnetometers could be used in such a situation. We detected the flux exclusion effect in a superconductor by monitoring the magnetic resonance spectrum of a large ensemble of NV centers in diamond. Our results show that phase transitions can be ascertained in a bulk superconductor with this technique. We also discovered temperature-dependent behavior of the zero-field splitting parameter D and conclude that the general implementation of such measurements may require compensation schemes.
The social cost of atmospheric release

I present a multi-impact economic valuation framework called the Social Cost of Atmospheric Release (SCAR) that extends the Social Cost of Carbon (SCC) used previously for carbon dioxide (CO2) to a broader range of pollutants and impacts. Values consistently incorporate health impacts of air quality along with climate damages. The latter include damages associated with aerosol-induced hydrologic cycle changes that lead to net climate benefits when reducing cooling aerosols. Evaluating a 1 % reduction in current global emissions, benefits with a high discount rate are greatest for reductions of co-emitted products of incomplete combustion (PIC), followed by sulfur dioxide (SO2), nitrogen oxides (NOx) and then CO2, ammonia and methane. With a low discount rate, benefits are greatest for PIC, with CO2 and SO2 next, followed by NOx and methane. These results suggest that efforts to mitigate atmosphere-related environmental damages should target a broad set of emissions including CO2, methane and aerosol/ozone precursors. Illustrative calculations indicate environmental damages are $330-970 billion yr−1 for current US electricity generation (~14–34¢ per kWh for coal, ~4–18¢ for gas) and $3.80 (−1.80/+2.10) per gallon of gasoline ($4.80 (−3.10/+3.50) per gallon for diesel). These results suggest that total atmosphere-related environmental damages plus generation costs are much greater for coal-fired power than other types of electricity generation, and that damages associated with gasoline vehicles substantially exceed those for electric vehicles.
Ramjet Propulsion for Single-Stage-to-Orbit Vehicles

The concept of single stage earth-to-orbit transportation is studied with respect to existing and projected ramjet technology. Four types of ramjet are analyzed: fan ejector, fan ramjet, supersonic combustion ramjet, and fan ramjet with turbojet boosters. A fan ramjet with a removable fan, with separate rockets for the non-air-breathing flight phase, is considered superior to an ejector ramjet, for both ease of orbit insertion and payload boost capability. Vehicle design is also discussed in terms of trajectory integration and optimization, aerodynamic trim and stability, and complete mass estimation. Graphs are presented showing Mach number for air-breathing and non-air-breathing flight, specific impulse from various ramjet engines, and orbital-insertion parameters.
Enantioselective synthesis of a halichondrin B C(20)→C(36) precursor

Abstract Differential functionalization of the nearly symmetrical bis(dihydropyran) 3 is described, leading to the C(20)→C(36) halichondrin B precursor 1. Double hydroboration, regioselective mono-protection of the resulting diol and two-directional chain extension are featured.
A Van Leusen deprotection-cyclization strategy as a fast entry into two imidazoquinoxaline families

A concise synthesis of two pharmacologically relevant classes of molecules possessing the imidazoquinoxaline core is reported. The protocol involves use of 1,2-phenylenediamines and glyoxylic acid derivatives, namely ethyl glyoxylate or benzylglyoxamide, along with tosylmethylisocyanides in a microwave-assisted Van Leusen three-component condensation. Subsequent unmasking (Boc removal) of an internal amino-nucleophile promotes deprotection and cyclization that take place either spontaneously in a one-pot fashion to give 8 or upon acidic treatment under microwave irradiation after isolation of the imidazole intermediate to give 11. Of note, a tricyclic framework is hence assembled by means of a rapid and straightforward method with a high bond-forming efficiency.
Exploitation of aeroelastic effects for drift reduction, in an all-polymer air flow sensor

Abstract This paper presents a vibration amplitude measurement method that greatly reduces the effects of baseline resistance drift in an all-polymer piezoresistive flow sensor or microtuft. The sensor fabrication is based on flexible printed circuit board (flex-PCB) technology to enable the potential for low-cost and scalable manufacture. Drift reduction is accomplished by discriminating the flow-induced vibration (‘ flutter ’) amplitude of the microtuft-based sensor as a function of flow velocity. Flutter peak-to-peak amplitude is measured using a microcontroller-based custom readout circuit. The fabricated sensor with the readout circuitry demonstrated a drift error of 2.8 mV/h, which corresponds to a flow-referenced drift error of 0.2 m/s of wind velocity per hour. The sensor has a sensitivity of 14.5 mV/(m/s) with less than 1% non-linearity over the velocity range of 5–16 m/s. The proposed vibration amplitude measurement method is also applied to a sensor array with a modified structure and a reduced dimension, which demonstrated a sensitivity of 13.2 mV/(m/s) with a flow-referenced drift error of 0.03 m/s of wind velocity per hour.
A NUMERICAL ALGORITHM FOR MODELING MULTIGROUP NEUTRINO-RADIATION HYDRODYNAMICS IN TWO SPATIAL DIMENSIONS

It is now generally agreed that multidimensional, multigroup, neutrino-radiation hydrodynamics (RHD) is an indispensable element of any realistic model of stellar-core collapse, core-collapse supernovae, and proto-neutron star instabilities. We have developed a new, two-dimensional, multigroup algorithm that can model neutrino-RHD flows in core-collapse supernovae. Our algorithm uses an approach similar to the ZEUS family of algorithms, originally developed by Stone and Norman. However, this completely new implementation extends that previous work in three significant ways: first, we incorporate multispecies, multigroup RHD in a flux-limited-diffusion approximation. Our approach is capable of modeling pair-coupled neutrino-RHD, and includes effects of Pauli blocking in the collision integrals. Blocking gives rise to nonlinearities in the discretized radiation-transport equations, which we evolve implicitly in time. We employ parallelized Newton-Krylov methods to obtain a solution of these nonlinear, implicit equations. Our second major extension to the ZEUS algorithm is the inclusion of an electron conservation equation that describes the evolution of electron-number density in the hydrodynamic flow. This permits calculating deleptonization of a stellar core. Our third extension modifies the hydrodynamics algorithm to accommodate realistic, complex equations of state, including those having nonconvex behavior. In this paper, we present a description of our complete algorithm, giving sufficient details to allow others to implement, reproduce, and extend our work. Finite-differencing details are presented in appendices. We also discuss implementation of this algorithm on state-of-the-art, parallel-computing architectures. Finally, we present results of verification tests that demonstrate the numerical accuracy of this algorithm on diverse hydrodynamic, gravitational, radiation-transport, and RHD sample problems. We believe our methods to be of general use in a variety of model settings where radiation transport or RHD is important. Extension of this work to three spatial dimensions is straightforward.
A fracture model for fiber reinforced cementitious materials

Abstract The present study describes the framework and the major results of a statistical model developed to predict the tensile properties of discontinuous fiber reinforced cementitious materials, with particular emphasis on fiber reinforced concrete. As macroscopically the fracture behavior of these composites varies from ductile to brittle depending mainly on the fiber length, the model is divided into two major parts. The first one, simulating ductile failure, is based on the mechanics and statistics of composite materials. The second, covering brittle failure, incorporates a fracture mechanics criterion in the analysis. Each formulation leads essentially to the assessment of the composite characteristic tensile strength and its distribution functions. The chain weakest link concept of reliability theory is then applied to bound the overall model and provide results as modified by the size of the tensile member.
Introduction Shared-Use Vehicle Services for Sustainable Transportation: Carsharing, Bikesharing, and Personal Vehicle Sharing across the Globe

This special issue of the International Journal of Sustainable Transportation highlights developments in shared-use vehicle research, in particular carsharing, public bikesharing, and personal vehi...
The role of spread spectrum in packet radio networks

This paper is devoted to an examination of the key features of spread-spectrum signaling in packet radio networks. The multiple-access capability, capture, and anti-multipath capability of spread spectrum are the principal topics, and the basic features of spread spectrum that enable it to provide these capabilities are illustrated. The interaction between the spread-spectrum signaling and the network protocols is discussed. Methods for performance evaluation are reviewed, and analytical results on the multiple-access capability of spread spectrum are presented.
Taxable Income, Future Earnings, and Equity Values

We investigate the ability of a tax‐based fundamental—the ratio of tax‐to‐book income—to predict earnings growth and stock returns and to explain the earnings‐price ratio. This tax fundamental reflects both temporary and permanent book‐tax differences as well as tax accruals, such as changes in the tax valuation allowance. We find that the tax‐to‐book income ratio predicts subsequent five‐year earnings changes, both before and after the implementation of Statement of Financial Accounting Standards (SFAS) No. 109 in 1993. For the pre‐SFAS No. 109 period, the tax information is unrelated to contemporaneous earnings‐price ratios and strongly related to subsequent stock returns. Conversely, for the post‐SFAS No. 109 period, the tax fundamental is strongly related to contemporaneous earnings‐price ratios and only weakly related to subsequent stock returns, indicating improvement over time in investors' perceptions of the implications of the tax information for future earnings. Deferred taxes, a component of ou...
Vortices in Protoplanetary Disks

We use a high-order accuracy spectral code to carry out two-dimensional, time-dependent numerical simulations of vortices in accretion disks. In particular, we examine the stability and the lifetime of vortices in circumstellar disks around young stellar objects. The results show that cyclonic vortices dissipate quickly, while anticyclonic vortices can survive in the flow for hundreds of orbits. When more than one vortex is present, the anticyclonic vortices interact through vorticity waves and merge together to form larger vortices. The exponential decay time τ of anticyclonic vortices is of the order of 30-60 orbital periods for a viscosity parameter α ≈ 10-4 (and it increases to τ ≈ 315 for α = 10-5), which is sufficiently long to allow heavy dust particles to rapidly concentrate in the core of anticyclonic vortices in protoplanetary disks. This dust concentration increases the local density of centimeter-sized grains, thereby favoring the formation of larger scale objects that are then capable of efficiently triggering a state of gravitational instability. The relatively long-lived vortices discussed here may therefore play a key role in the formation process of giant planets.
The Relative Impacts of Trails and Greenbelts on Home Price

This study examines the impacts of trails and greenbelts and other amenities on home value. Using the hedonic framework the study provides analyses of a database consisting of roughly 10,000 sales of homes occurring from April 2001 to March 2002 in and around San Antonio, Bexar County, Texas. Among other things, our study shows that trails, greenbelts, and trails with greenbelts (or greenways) are associated with roughly 2, 4, and 5%, price premiums, respectively. The following amenities: proximity to golf course, neighborhood playground, tennis court, neighborhood pool, view, and cul-de-sac, all add significantly to home value.
REAL DOUBLE COSET SPACES AND THEIR INVARIANTS

Abstract Let G be a real form of a complex reductive group. Suppose that we are given involutions σ and θ of G. Let H = G σ denote the fixed group of σ and let K = G θ denote the fixed group of θ. We are interested in calculating the double coset space H \ G / K . We use moment map and invariant theoretic techniques to calculate the double cosets, especially the ones that are closed. One salient point of our results is a stratification of a quotient of a compact torus over which the closed double cosets fiber as a collection of trivial bundles.
Iridium-catalyzed diborylation of benzylic C–H bonds directed by a hydrosilyl group: synthesis of 1,1-benzyldiboronate esters

We describe a regioselective diborylation of primary benzylic C–H bonds catalyzed by [Ir(COD)OMe]2 and 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy). The hydrosilyl group acts as a traceless directing group, providing access to a range of 1,1-benzyldiboronate esters in good yields. Transformations of the 1,1-benzyldiboronate ester products include chemoselective Suzuki–Miyaura cross-couplings and synthesis of tetrasubstituted alkenyl boronate esters.
The supremum of brownian local times on Hölder curves

Abstract For f :[0,1]→ R , we consider Lft, the local time of space-time Brownian motion on the curve f. Let S α be the class of all functions whose Holder norm of order α is less than or equal to 1. We show that the supremum of Lf1 over f in S α is finite if α>1/2 and infinite if α
An Explanation for Unintentional Optimism in Analysts' Earnings Forecasts

Archival studies report that analysts' annual earnings forecasts are optimistic, particularly for firms reporting recent losses. This study addresses whether forecast optimism is an unintentional consequence of analysts' reactions to the structure of information about managers' future plans. I investigate whether analysts who are forecasting earnings use processes consistent with scenario thinking: envisioning a sequence of events in which proposed actions lead to future outcomes. I study professional sell‐side analysts in a 2×2 between‐subjects experiment with the structure of information (scenario vs. list) and the sign of prior earnings (loss vs. profit) as independent variables. I find that analysts make more optimistic two‐year‐ahead earnings forecasts when provided information about a manager's future plans framed as scenarios than when provided the same information framed as lists. I also find that scenario‐induced optimism is greater for a firm with prior losses than for a firm with prior profits....
ACL2 Meets the GPU: Formalizing a CUDA-based Parallelizable All-Pairs Shortest Path Algorithm in ACL2

As Graphics Processing Units (GPUs) have gained in capability and GPU development environments have matured, developers are increasingly turning to the GPU to off-load the main host CPU of numerically-intensive, parallelizable computations. Modern GPUs feature hundreds of cores, and offer programming niceties such as double-precision floating point, and even limited recursion. This shift from CPU to GPU, however, raises the question: how do we know that these new GPU-based algorithms are correct? In order to explore this new verification frontier, we formalized a parallelizable all-pairs shortest path (APSP) algorithm for weighted graphs, originally coded in NVIDIA’s CUDA language, in ACL2. The ACL2 specification is written using a single-threaded object (stobj) and tail recursion, as the stobj/tail recursion combination yields the most straightforward translation from imperative programming languages, as well as efficient, scalable executable specifications within ACL2 itself. The ACL2 version of the APSP algorithm can process millions of vertices and edges with little to no garbage generation, and executes at one-sixth the speed of a host-based version of APSP coded in C — a very respectable result for a theorem prover. In addition to formalizing the APSP algorithm (which uses Dijkstra’s shortest path algorithm at its core), we have also provided capability that the original APSP code lacked, namely shortest path recovery. Path recovery is accomplished using a secondary ACL2 stobj implementing a LIFO stack, which is proven correct. To conclude the experiment, we ported the ACL2 version of the APSP kernels back to C, resulting in a less than 5% slowdown, and also performed a partial back-port to CUDA, which, surprisingly, yielded a slight performance increase.
Gender as a postmodern category of paralysis

Synopsis It is not the purpose of this article to discuss the linguistic technicalities of the current debate in the United States over poststructural literary criticism, semiotics, new historicism, new cultural history, or cultural and symbolic anthropology. Rather, I focus on aspects of poststructuralism that I think may negatively affect the progress made by scholars in women's history over the last quarter century. My concern is with the possible motivations for, and the practical implications of, the “linguistic turn” in terms of feminist politics, public policy, and the writing and teaching of women's history in the United States and in countries where historical scholarship on women is only beginning to develop.
The True Title of Bayes’s Essay

New evidence is presented that Richard Price gave Thomas Bayes's famous essay a very different title from the commonly reported one. It is argued that this implies Price almost surely and Bayes not improbably embarked upon this work seeking a defensive tool to combat David Hume on an issue in theology.
Optimal aeroassisted guidance using Loh's term approximations

This paper presents three guidance algorithms for aerocapture and/or aeroassisted orbital transfer with plane change. All three algorithms are based on the approximate solution of an optimal control problem at each guidance update. The chief assumption is that Loh's term may be modeled as a function of the independent variable only. The first two algorithms maximize exit speed for fixed exit altitude, flight path angle and heading angle. The third minimizes, in one sense, the control effort for fixed exit altitude, flight path angle, heading angle and speed. Results are presented which indicate the near optimality of the solutions generated by the first two algorithms. Results are also presented which indicate the performance of the third algorithm in a simulation with unmodeled atmospheric density disturbances.
Zoning and fiscal interdependencies

Although there are strong theoretical reasons to regard optimal zoning and fiscal policies as simultaneous decisions, most empirical studies have focused on one type of decision or the other. Even fewer attempts have been made to study interdependencies between competing towns in their selection of zoning and fiscal policies. If these interdependencies are prevalent, autonomous local governments may pursue zoning, taxing, and spending policies that are locally rational but socially inefficient. In this study, an optimization model of the local economy is used to illustrate the nature of these interdependencies and to specify an appropriate empirical test. Data from 164 Connecticut townships are used to estimate the empirical model.
Concise synthesis of the chemopreventitive agent (+/-)-deguelin via a key 6-endo hydroarylation.

A concise total synthesis of (±)-deguelin was achieved with a longest linear sequence of six steps in 68% yield. A key step was the platinum-catalyzed 6-endo hydroarylation of an alkynone intermediate.
DETECTION AND ESTIMATION OF MULTIPLE WEAK SIGNALS IN NON-GAUSSIAN NOISE

We address the problem of efficient detection and estimation of multiple weak signals in severe noise. To address this problem, we propose a concentrated peak representation (CPR) in which the spectral energy is concentrated in spectral peaks, and only the magnitudes and locations of the peaks are retained. We base our process on the cross spectral representation we have previously applied to other problems. The advantage of this representation is that it preserves the energy in signal components while significantly reducing the data volume. We demonstrate the method on a composite signal consisting of one billion samples, reducing the data volume by a factor of 1000 or more, and we demonstrate the detection of weak signals in the reduced representation.
Noise generated from a flexible and elastically supported structure subject to turbulent boundary layer flow excitation

Abstract A numerical methodology based on the finite element and boundary element methods is presented for computing the noise radiated from a structure subject to boundary layer excitation. The new algorithm utilizes the fluctuating wall pressure in order to define the excitation on the structural–acoustic system. The developments target wind noise prediction for the sound radiated by the side glass window of an automobile. The glass-seal assembly is modeled as a flexible plate mounted on an elastic foundation with stiffness and damping characteristics. Numerical predictions are compared successfully to wind tunnel test data. Parametric analyses are performed in order to identify the characteristics of the seal that can lead to noise reduction.
A non-hermitean particle in a disordered world

Abstract There has been much recent work on the spectrum of the random non-hermitean Hamiltonian which models the physics of vortex line pinning in superconductors. This note is loosely based on the talk I gave at the conference “New Directions in Statistical Physics” held in Taipei, August 1997. We also give an expression for the spectrum within the WKB approximation.
Large conjugacy classes, projective Fraïssé limits and the pseudo-arc

We show that the automorphism group, Aut(ℙ), of a projective Fraisse limit ℙ, whose natural quotient is the pseudo-arc, has a comeager conjugacy class. This generalizes an unpublished result of Izhar Oppenheim that Aut(ℙ) (and consequently, the group of all homeomorphisms of the pseudo-arc) has a dense conjugacy class. We also present a simple proof of the result of Oppenheim.
A Branch-and-Price Approach to the Share-of-Choice Product Line Design Problem

We develop a branch-and-price algorithm for constructing an optimal product line using partworth estimates from choice-based conjoint analysis. The algorithm determines the specific attribute levels for each multiattribute product in a set of products to maximize the resulting product line's share of choice, i.e., the number of respondents for whom at least one new product's utility exceeds the respondent's reservation utility. Computational results using large commercial and simulated data sets demonstrate that the algorithm can identify provably optimal, robust solutions to realistically sized problems.
Synthesis and reactions of bis(arylimino)isoindoline complexes of dimolybdenum

Abstract Several dimolybdenum complexes have been synthesized which contain the planar tridentate ligand bis(arylimino)isoindoline, BAII. The BAII derivatives which have been successfully coordinated to the dimolybdenum unit include those in which the aryl group is pyridine, 4-methylpyridine, and 4-ethylpyridine. It was found that only one BAII ligand would attach to the dimolybdenum unit and that complexes with the formula Mo2(OAc)3(BAII) resulted. These complexes have one molybdenum coordinated to the BAII and one monodentate acetate while the other molybdenum is coordinated to two bidentate acetates. This structural assignment is supported by NMR, infrared and electronic absorption data. This is the first dimolybdenum complex which contains non-bridging acetates as well as being the first dimolybdenum complex with a planar tridentate ligand. Reaction of the complexes with excess acetic acid regenerates molybdenum acetate thus showing that the quadruple bond is intact in the BAII complexes.
Macrocyclization in the design of a conformationally constrained Grb2 SH2 domain inhibitor

Grubbs' olefin metathesis reaction was utilized to prepare a macrocyclic variant of a linear Grb2 SH2 domain antagonist in an attempt to induce a β-bend conformation known to be required for high affinity binding. In extracellular Grb2 SH2 domain binding assays, the macrocyclic analogue exhibited an approximate 100-fold enhancement in binding potency relative to its linear counterpart. The macrocycle was not as effective in whole cell binding assays as would be expected based on its extracellular binding potency.
Amplitude modulation of charge-density-wave domains in 1T-TaS2 at 300 K.

Measurements of the charge-density-wave (CDW) amplitude modulation in 1T-${\mathrm{TaS}}_{2}$ at room temperature has been made using a scanning tunneling microscope operating in the constant-current mode. The amplitude profiles are in good agreement with the profile predicted by the CDW domain model of Nakanishi and Shiba. Interference effects between the atomic and CDW lattices have been analyzed and do not modify these profiles significantly.
RCA Satcom: An example of weight optimized satellite design for maximum communications capacity

Abstract The communications mission of RCA Satcom entails antenna beam coverage of all fifty states, with Hawaiian service provided by an offset spot from the primary beam for the contiguous 48 states and Alaska. To achieve minimum cost per channel in the competitive U.S. domestic market, Globcom and Alascom specified that their satellite should (1) incorporate 24 wide-band transponder channels in the commercial, 4 6 GHz band, (2) contain sufficient power and orbit control capacity to maintain all 24 channels operating continuously for a minimum of eight years, and (3) be compatible with the Delta 3914 launch vehicle, whose development they had funded jointly with the McDonnell-Douglas Astronautics Corporation at no cost to the U.S. government. This combination of requirements thus defined a communications satellite whose channel capacity is twice that of other current Delta class spacecraft but whose cost, including the launch vehicle, is significantly less than that of the corresponding 24-channel Atlas-Centaur class spacecraft designs. To meet these demands weight-optimized designs were needed in four key subsystem areas: antennas, transponder multiplexers, power supply, and attitude control as well as in the structure itself. The resultant three-axis stabilized spacecraft design with sun-oriented solar panels provides maximum power and weight capability to the primary communications payload within the launch vehicle envelope.
An ab initio Monte Carlo study of low energy positron and electron implantation in elemental metals and multilayers

Abstract A Monte Carlo code developed at Brookhaven to study positron and electron implantation in solids will be discussed. This code models the trajectories of a large number of positrons or electrons as they move through the material and uses this information to calculate stopping profiles, backscattered fractions and transmitted fractions. The particle-atom interactions are incorporated via elastic and inelastic scattering cross-sections. The incident particle energies vary from 1 to 10 keV and the simulation stops when the particle energy goes down to 25 eV or if the particle is backscattered. Main results of our Monte Carlo simulations of the mean implantation depth and implantation profiles for both semi-infinite metallic elements and multilayers will be discussed.
The Central Region of Barred Galaxies: Molecular Environment, Starbursts, and Secular Evolution

Stellar bars drive gas into the circumnuclear (CN) region of galaxies. To investigate the fate of the CN gas and star formation (SF), we study a sample of barred nonstarbursts and starbursts with high-resolution CO, optical, Hα, radio continuum, Brγ, and HST data, and find the following. (1) The inner kiloparsec of bars differs markedly from the outer disk. It hosts molecular gas surface densities Σgas-m of 500-3500 M☉ pc-2, gas mass fractions of 10%-30%, and epicyclic frequencies of several 100-1000 km s-1 kpc-1. Consequently, in the CN region gravitational instabilities can only grow at high gas densities and on short timescales, explaining in part why powerful starbursts reside there. (2) Across the sample, we find bar pattern speeds with upper limits of 43-115 km s-1 pc-1 and outer inner Lindblad resonance radii of >500 pc. (3) Barred starbursts and nonstarbursts have CN SF rates of 3-11 and 0.1-2 M☉ yr-1, despite similar CN gas masses. The Σgas-m value in the starbursts is larger (1000-3500 M☉ pc-2) and close to the Toomre critical density over a large region. (4) Molecular gas makes up 10%-30% of the CN dynamical mass and fuels large CN SF rates in the starbursts, building young, massive, high-V/σ components. Implications for secular evolution along the Hubble sequence are discussed.
A taxonomy of optical architectures for LCOS projection displays

Liquid-crystal-on-silicon (LCOS) technology enables affordable, true high definition resolution televisions for the growing rear projection display market. In this review, we will present a taxonomy of LCOS optical architectures and survey some recent advances in LCOS panels and the optical systems that support them.