cssi/SciSciGPT-SciSciNet huggingface dataset:
Some Finiteness Properties of Regular Vertex Operator Algebras

Abstract We give a natural extension of the notion of the contragredient module for a vertex operator algebra. By using this extension we prove that for regular vertex operator algebras, Zhu's C 2 -finiteness condition holds, fusion rules (for any three irreducible modules) are finite and the vertex operator algebras themselves are finitely generated.
On K-stability of reductive varieties

G. Tian and S.K. Donaldson formulated a conjecture relating GIT stability of a polarized algebraic variety to the existence of a Kahler metric of constant scalar curvature. In [D3] Donaldson partially confirmed it in the case of projective toric varieties. In this paper we extend Donaldson’s results and computations to a new case, that of reductive varieties.
The effect of smoothed solar wind inputs on global modeling results

[1] This study investigates the role of fluctuations in the solar wind parameters in triggering a magnetic storm and assesses the storm simulation ability of the Space Weather Modeling Framework (SWMF) through a model-data comparison. The event of 22 September 1999 is examined through global magnetosphere simulations, using as input Advanced Composition Explorer (ACE) observations (4 min temporal resolution) along with running averages of this data with windows of 60, 120, and 180 min. It is noted that for this storm the model produces a two phase, fast then slow recovery phase due to a sudden drop in plasma sheet density during the interval of southward interplanetary magnetic field (IMF). Also, smoothing the input with a window larger than 60 min changes the entire magnetosphere and reduces the plasma sheet density and pressure, therefore a less intense storm develops. It is worth mentioning that the main phase (measured from Storm Sudden Commencement to minimum Dst) for this magnetic storm lasted about 3 h. This explains the change in the Dst profile for the 120 and 180 min averaged input. Averaging only IMF B z or solar wind density reveals that all input parameters are important for the development of the storm, but B z is the most significant. Also, comparison with Dst predictions (using the formula of O'Brien and McPherron (2000)) are presented and discussed. For all cases studied, there are no significant differences for Cross Polar Cap Potential (CPCP) in both hemispheres, while the nightside plasma sheet density shows a sharp drop when the input is averaged over 60 min or more. Our results indicate that the magnetosphere responds nonlinearly to the changes in the energy input, suggesting the need for a threshold in the amount of energy transferred to the system in order for the ring current to develop. Further increase of the energy input leads to a saturation limit where the inner magnetosphere response is no longer affected by any additional amount of energy contained within high-frequency oscillations, because the magnetospheric system acts as a low-pass filter on the interplanetary magnetic field.
PROFESSIONALISM CONSEQUENCES OF LAW FIRM INVESTMENTS IN CLIENTS: AN EMPIRICAL ASSESSMENT

Increasing attention has recently been focused on conflicts of interest among public companies and the professionals assisting those companies in selling or maintaining a market in their securities. Various financial relationships, in addition to fees for securities-related matters, may create conflicts of interest. Although the conflicts of interest involving accounting firms and investment banks have received most prominent recent attention, law firms also may have significant conflicts of interest. For example, a law firm may have an equity interest in its client. The Article provides an empirical assessment of the consequences of those law firm investments. A data set was assembled consisting of common stock IPOs of non-financial firms in 1998 and 1999 for which Securities Data Company reported the required information. The Article examines the changes in prices from proxies for prices estimated during "beauty pageants," where investment banks are selected to manage IPOs, to the actual offer prices. The Article argues those price changes reflect the level of aggression of the participating counsel in requiring negative disclosure, a less aggressive approach either (i) not requiring disclosure of information that would be required to be disclosed were the law firm not to have an investment in its client; or (ii) allowing the disclosure to be in more innocuous language, i.e., burying the disclosure; or (iii) decreasing diligence procedures, resulting in the law firm not becoming aware of adverse information that it otherwise would uncover. The results of ordinary least squares regressions show a positive relationship, statistically significant at the 1% or 5% level, between those price changes per share, whether expressed on a dollar basis or a percentage basis, and the frequency with which the issuer's lawyer has such an interest. That is, a greater frequency with which the law firm has investments in clients it takes public is associated with a positive change from a proxy for the beauty pageant price to the actual IPO price. The results also show a positive relationship, statistically significant at the 1% or 10% level, between those price changes, on a dollar basis, and the amount of the law firm's investment in the specific client being taken public. The relationship between law firm investment in the particular firm being taken public and the price adjustment is of the same sign, but generally not statistically significant, in models where the dependent variable is expressed on a percentage basis. The Article concludes greater disclosure of the nature of these investments should be mandated and raises concerns whether these investments should be proscribed.
Measuring market power in the French Comté cheese market.

A new empirical industrial organisation approach is used to measure seller market power in the French Comte cheese market, characterised by government-approved supply control. The estimation is performed on quarterly data at the wholesale stage over the period 1985--2005. Three different elasticity shifters are included in the demand specification, and the supply equation accounts for the existence of the European dairy quota policy. The market power estimate is small and statistically insignificant. Monopoly is clearly rejected. Results appear to be robust to the choice of functional form and suggest little effect of the supply control scheme on consumer prices. Oxford University Press and Foundation for the European Review of Agricultural Economics 2009; all rights reserved. For permissions, please email journals.permissions@oxfordjournals.org, Oxford University Press.
Miura opers and critical points of master functions

Critical points of a master function associated to a simple Lie algebra\(\mathfrak{g}\) come in families called the populations [11]. We prove that a population is isomorphic to the flag variety of the Langlands dual Lie algebra\(^t \mathfrak{g}\). The proof is based on the correspondence between critical points and differential operators called the Miura opers.
Gate Oxide Reliability for Nano-Scale CMOS

The reliability of the gate oxide in microelectronics, i.e., the ability of a thin film of this material to retain its excellent dielectric properties while subjected to high electric fields, has been a perennial concern over the last 40-45 years. Two dominant gate oxide failure mechanisms, dielectric breakdown and the negative bias instability, have continued to cause concern as MOSFET devices have scaled to nanometer dimensions
Enantiospecific generation of anti-aldol adducts via conjugate addition to 5-methylene-1,3-dioxan-4-ones

Abstract Michael additions to the exocyclic olefins of optically pure dioxanones (prepared via the asymmetric Baylis-Hillman reaction) are studied. The products can be obtained in excellent diastereoselectivity to ultimately provide products equivalent to those derived via anti aldol additions. Quaternary centers can also be created with good selectivity via this protocol.
A Self-consistent NLTE-Spectra Synthesis Model of FeLoBAL QSOs

We present detailed radiative transfer spectral synthesis models for the iron low ionization broad absorption line (FeLoBAL) active galactic nuclei (AGNs) FIRST J121442.3+280329 and ISO J005645.1–273816. Detailed non-LTE spectral synthesis with a spherically symmetric outflow reproduces the observed spectra very well across a large wavelength range. While exact spherical symmetry is probably not required, our model fits are of high quality, and thus very large covering fractions are strongly implied by our results. We constrain the kinetic energy and mass in the ejecta and discuss their implications on the accretion rate. Our results support the idea that FeLoBALs may be an evolutionary stage in the development of more "ordinary" QSOs.
Test of the transmission line model and the traveling current source model with triggered lightning return strokes at very close range

We test the two simplest and most conceptually different return stroke models, the transmission line model (TLM) and the traveling current source model (TCSM), by comparing the first microsecond of model-predicted electric and magnetic field wave forms and field derivative wave forms at 15 m and 30 m with the corresponding measured wave forms from triggered lightning return strokes. In the TLM the return stroke process is modeled as a current wave injected at the base of the lightning channel and propagating upward along the channel with neither attenuation nor dispersion and at an assumed constant speed. In the TCSM the return stroke process is modeled as a current source traveling upward at an assumed constant speed and injecting a current wave into the channel, which then propagates downward at the speed of light and is absorbed at ground without reflection. The electric and magnetic fields were calculated from Maxwell's equations given the measured current or current derivative at the channel base, an assumed return stroke speed, and the temporal and spatial distribution of the channel current specified by the return stroke model. Electric and magnetic fields and their derivatives were measured 15 m and 30 m from rocket-triggered lightning during the summer of 2001 at the International Center for Lightning Research and Testing at Camp Blanding, Florida. We present data from a five-stroke flash, S0105, and compare the measured fields and field derivatives with the model-predicted ones for three assumed lightning return stroke speeds, v = 1 x 10 8 m/s, v = 2 x 10 8 m/s, and v = 2.99 × 10 8 m/s (essentially the speed of light). The results presented show that the TLM works reasonably well in predicting the measured electric and magnetic fields (field derivatives) at 15 m and 30 m if return stroke speeds during the first microsecond are chosen to be between 1 × 10 8 m/s and 2 x 10 8 m/s (near 2 x 10 8 m/s). In general, the TLM works better in predicting the measured field derivatives than in predicting the measured fields. The TCSM does not adequately predict either the measured electric fields or the measured electric and magnetic field derivatives at 15 and 30 m during the first microsecond or so.
Very fast computation of polynomial remainder sequence coefficient signs

Polynomial remainder sequences are the basis of many important algorithms in symbolic and algebraic manipulation. In a number of these algorithms, the actual coefficients of the sequence are not required; rather, the method uses the signs of the coefficients. Present techniques, however, compute the exact coefficients (or a mixed radix representation of them), and then obtain the signs. This paper discusses a new approach in which interval arithmetic is used to obtain the signs of the coefficients without computing their exact values. Comparisons of this method with analogous standard techniques show empirical computing time reductions of two orders of magnitude for even relatively small cases.
Chaos in linear distributed systems

Chaos can occur in linear distributed dynamical systems. Recent results of Godefroy and Shapiro show that certain linear analytic semi-groups exhibit chaotic behavior.
Space Hierarchy Results for Randomized and other Semantic Models

We prove space hierarchy and separation results for randomized and other semantic models of computation with advice where a machine is only required to behave appropriately when given the correct advice sequence. Previous works on hierarchy and separation theorems for such models focused on time as the resource. We obtain tighter results with space as the resource. Our main theorems deal with space-bounded randomized machines that always halt. Let s(n) be any space-constructible monotone function that is Ω(log n) and let s′(n) be any function such that s′(n) = ω(s(n + as(n))) for all constants a. There exists a language computable by two-sided error randomized machines using s′(n) space and one bit of advice that is not computable by two-sided error randomized machines using s(n) space and min(s(n), n) bits of advice. There exists a language computable by zero-sided error randomized machines in space s′(n) with one bit of advice that is not computable by one-sided error randomized machines using s(n) space and min(s(n), n) bits of advice. If, in addition, s(n) = O(n) then the condition on s′ above can be relaxed to s′(n) = ω(s(n + 1)). This yields tight space hierarchies for typical space bounds s(n) that are at most linear. We also obtain results that apply to generic semantic models of computation.
Catalytic methyl transfer from dimethylcarbonate to carboxylic acids.

Although methylation reactions are commonplace, currently used reagents are hazardous, toxic, and/or unstable. Dimethylcarbonate has been put forth as an inexpensive, nontoxic, and “green” potential methylating reagent. Herein we report a general, base-catalyzed methyl transfer from dimethylcarbonate to carboxylic acids. High selectivity for esterification is observed even in the presence of unprotected phenols, and the mild reaction conditions enable conservation of stereochemistry at epimerizable stereocenters. Isotope-labeling studies suggest a mechanism proceeding by direct methyl transfer from dimethylcarbonate to the substrate.
Absolute configuration, conformation, and chiral properties of flavanone-(3→8″)-flavone biflavonoids from Rheedia acuminata

Abstract The absolute configurations of three flavanone-(3→8″)-flavone type biflavonoids, (+)-morelloflavone ( 1 ), (+)-morelloflavone-7-sulfate ( 2 ) and (+)-volkensiflavone-7-sulfate ( 3 ) isolated from Rheedia acuminata were confirmed by circular dichroism as 2 R ,3 S , hence clarifying the literature confusion of 2 S ,3 R absolute configuration for (+)-morelloflavone. The conformations of this class of biflavonoids were studied for the first time by variable temperature NMR, NOESY, and computational calculations using a semi-empirical AM1 method. The coexistence of two conformers for morelloflavone ( 1 ) in solution at room temperature was confirmed by variable temperature NMR experiments. NOESY and computational calculations indicated that in the major and minor conformers 1a and 1b , respectively, the flavone DEF moiety is extended above and below the plane of the A/C-ring of the flavanone ABC unit, respectively. The C-3 proton of the C-ring of morelloflavone ( 1 ) is exchangeable by deuterium in acetone- d 6 /D 2 O at ambient temperature with retention of configuration, indicating considerable chiral stability of this class of biflavonoids.
The littlest Higgs in anti-de Sitter space

We implement the SU(5)/SO(5) littlest Higgs theory in a slice of 5D Anti-de Sitter space bounded by a UV brane and an IR brane. In this model, there is a bulk SU(5) gauge symmetry that is broken to SO(5) on the IR brane, and the Higgs boson is contained in the Goldstones from this breaking. All of the interactions on the IR brane preserve the global symmetries that protect the Higgs mass, but a radiative potential is generated through loops that stretch to the UV brane where there are explicit SU(5) violating boundary conditions. Like the original littlest Higgs, this model exhibits collective breaking in that two interactions must be turned on in order to generate a Higgs potential. In AdS space, however, collective breaking does not appear in coupling constants directly but rather in the choice of UV brane boundary conditions. We match this AdS construction to the known low energy structure of the littlest Higgs and comment on some of the tensions inherent in the AdS construction. We calculate the 5D Coleman-Weinberg effective potential for the Higgs and find that collective breaking is manifest. In a simplified model with only the SU(2) gauge structure and the top quark, the physical Higgs mass can be of order 200 GeV with no considerable fine tuning (25%). We sketch a more realistic model involving the entire gauge and fermion structure that also implements T-parity, and we comment on the tension between T-parity and flavor structure.
Cortical contributions to saccadic suppression

The stability of visual perception is partly maintained by saccadic suppression: the selective reduction of visual sensitivity that accompanies rapid eye movements. The neural mechanisms responsible for this reduced perisaccadic visibility remain unknown, but the Lateral Geniculate Nucleus (LGN) has been proposed as a likely site. Our data show, however, that the saccadic suppression of a target flashed in the right visual hemifield increased with an increase in background luminance in the left visual hemifield. Because each LGN only receives retinal input from a single hemifield, this hemifield interaction cannot be explained solely on the basis of neural mechanisms operating in the LGN. Instead, this suggests that saccadic suppression must involve processing in higher level cortical areas that have access to a considerable part of the ipsilateral hemifield.
Induction-time measurements at a particle bed

Abstract Induction times for a variety of natural hydrophobic minerals have been measured at a particle bed with an electronic induction timer. The experimental results clearly show a strong dependence on particle size. Detailed analysis suggests that the measured induction time at a particle bed should properly be defined as the bubble attachment time, which consists of the actual induction time (film-rupture time) and the film-displacement time. The relative significance of these two variables at a polished surface is quite different from that at particle surfaces.
A Relation Between N = 8 Gauge Theories in Three Dimensions

We show that three-dimensional N = 8 Sp(N) and SO(2N+1) gauge theories flow to the same strong coupling fixed point. As a consequence, the corresponding orientifold two-planes in type IIA string theory are described at strong coupling and low-energies by the same M theory background. In the large N limit, these assertions are confirmed by studying discrete torsion in the supergravity theory corresponding to membranes on 8/2.
Response of the Sphere Wake to Freestream Fluctuations

Direct numerical simulations have been used to investigate the response of the wake of a sphere to freestream fluctuations. This study has been motivated by the need to understand particle-induced turbulence enhancement in particulate flows. A sequence of simulations of flow past a sphere have been carried out where the frequency and amplitude of the freestream fluctuations and the flow Reynolds number has been varied systematically. It has been suggested that turbulence enhancement is primarily caused by vortex shedding from particles (Gore and Crowe, 1989; Hetsroni, 1989). Our simulations of the forced wake indicate that turbulence enhancement may be attributed to natural vortex shedding only when the freestream fluctuation level is low and the Reynolds number is greater than about 300. In addition to natural vortex shedding, the current simulations also suggest another mechanism for turbulence enhancement. It is found that in the presence of freestream fluctuations, the wake behaves like an oscillator and returns large amounts of kinetic energy to the surrounding fluid at resonance. This mechanism is not associated with natural vortex shedding and is therefore capable of enhancing freestream turbulence even at Reynolds numbers less than 300. Simulations also indicate that when the turbulence intensity of the carrier fluid is high, this resonance mechanism might be solely responsible for turbulence enhancement. Finally, our simulations also suggest a possible explanation for the correlation between turbulence enhancement and the ratio of the particle size to the size of energy containing eddies of turbulence found by Gore and Crowe (1989).
Lipid-shelled vehicles: engineering for ultrasound molecular imaging and drug delivery.

Ultrasound pressure waves can map the location of lipid-stabilized gas micro-bubbles after their intravenous administration in the body, facilitating an estimate of vascular density and microvascular flow rate. Microbubbles are currently approved by the Food and Drug Administration as ultrasound contrast agents for visualizing opacification of the left ventricle in echocardiography. However, the interaction of ultrasound waves with intravenously-injected lipid-shelled particles, including both liposomes and microbubbles, is a far richer field. Particles can be designed for molecular imaging and loaded with drugs or genes; the mechanical and thermal properties of ultrasound can then effect localized drug release. In this Account, we provide an overview of the engineering of lipid-shelled microbubbles (typical diameter 1000−10 000 nm) and liposomes (typical diameter 65−120 nm) for ultrasound-based applications in molecular imaging and drug delivery. The chemistries of the shell and core can be optimized to ...
Palladium-catalyzed hydroalkylation of styrenes with organozinc reagents to form carbon-carbon sp3-sp3 bonds under oxidative conditions.

An unconventional route for the formation of sp3−sp3 C−C bonds from various styrenes and an organozinc reagent in a formal alkene hydroalkylation process is detailed. Mechanistically, this process ...
Minimum Spacing of Thermally Induced Cracks in Brittle Solids

When the temperature at the free surface of a linearly elastic brittle half-plane, which is initially uniform throughout the solid, is suddenly reduced by a large amount and then kept constant thereafter, a thermal boundary layer whose thickness increases with time, forms close to the free surface. Because of the consequent thermal contraction, edge cracks may form within the thermal boundary layer. For a system of equally spaced straight-edge cracks, growing collinearly with increasing thickness of the thermal boundary layer, the average minimum crack spacing is estimated on the basis of: (a) energy consideration; (b) stress consideration; and (c) consideration of stability of the growth of interacting cracks. It is shown that for a given temperature profile, one can develop a general stability chart which, in particular, gives a complete growth regime of the interacting cracks (no crack branching is included).
TRIDENT: a new maintenance weapon

Everyone is familiar with maintenance. It is a necessary requirement for almost everything we have, from spacecraft and automobiles, to the heels on your shoes. The maintenance that this paper is concerned with is that of business machines and their associated products. These devices are the means to the end required for your business and other endeavors.
Oscillatory Control of Shock-Induced Separation

An experimental investigation, aimed at delaying e ow separation as a result of the occurrence of a shockwave/boundary-layer interaction, is reported. The experiment was performed using a NACA 0015 airfoil at highReynolds-number incompressible and compressible e ow conditions. The effects of Mach and Reynolds numbers were identie ed, using the capabilities of the cryogenic-pressurized facility to maintain one parameter e xed and change the other. The main objectives of the experiment were to study the effects of periodic excitation on airfoil drag divergence and to alleviate the severe unsteadiness associated with shock-induced separation (known as buffeting). Zero-mass-e ux oscillatory blowing was introduced through a downstream directed slot located at 10% chord on the upper surface of the NACA 0015 airfoil. The effective frequencies generated 2 ‐4 vortices over the separated region, regardless of the Mach number. Even though the excitation was introduced upstream of the shock wave, it had pronounced effects downstream of it. Wake dee cit (associated with drag ) and unsteadiness (associated with buffeting ) were reduced. The spectral content of the wake pressure e uctuations indicates steadier e ow throughout the frequency rangewhen excitation isapplied. This is especially evident at low frequencieswhich are more likely to interact with the airframe.
The lunar magma ocean: Reconciling the solidification process with lunar petrology and geochronology

Abstract The Moon is thought to have originated with a magma ocean that produced a plagioclase flotation crust as solidification proceeded. Ages of anorthositic crust range over at least 200 million years. The model for solidification presented here integrates chemical and physical constraints of lunar magma ocean solidification to determine (1) the final thickness of flotation crust generated by a fractionally solidifying magma ocean, (2) the timescale of crystallization before plagioclase is a stable phase, (3) the timescale of solidification after the formation of the plagioclase flotation crust, and (4) the post-overturn lunar mantle composition and structure. We find that magma oceans of as much as 1000 km depth are consistent with creating an anorthositic crust 40 to 50 km in thickness. Solidification of the magma ocean prior to formation of the flotation crust may occur on the order of 1000 years, and complete solidification would require additional ten to tens of millions of years. Reconciling these short model timescales with radiometric dates of crustal samples requires either a very late-forming Moon combined with finding older crustal ages to be incorrect, or calling on tidal heating of the crust by the early Earth to prolong solidification. Gravitationally driven overturn of cumulates during tidal heating provides a mechanism for creating the compositions and ages of the lunar Mg suite of crustal rocks. Further, we find that upon crystallization, the Moon likely began with an azimuthally heterogeneous, gravitationally stable mantle, after magma ocean cumulate overturn. This result may help explain the experimentally determined origin of picritic glasses at similar depths but from different source materials.
Effect of catalyst structure on methane oxidation over palladium on alumina

Abstract A series of palladium on alumina catalysts were prepared and tested for methane oxidation at 300°C, 50 Torr methane, 110 Torr oxygen, 900 Torr helium, and conversions less than 2%. During the reaction the palladium particles are oxidized. The extent of oxidation increases with decreasing particle size and increasing number of crystal imperfections. Palladium oxidation breaks apart the crystals, so that all the oxide is exposed and participates in catalysis. Turnover rates for methane oxidation, based on the oxygen uptake at the temperature and oxygen pressure of the reaction, vary from 0.004 to 0.15 s−1. Our results suggest that the palladium oxide dispersed over the alumina is much less active than the oxide dispersed over the surface of the palladium crystallites. Also, chlorine deposited during catalyst preparation may inhibit the rate of methane oxidation.
Nontriviality of the linear sigma model

We consider techniques (based on an ultraviolet cutoff) used to prove that the pure boson (\(\phi^4)_4\) field theory is trivial and apply them instead to the dynamically generated quark-level linear sigma model. This cutoff approach leads to the conclusion that the latter field theory is in fact nontrivial.
Boundaries in M-theory

Abstract We formulate boundary conditions for an open membrane that ends on the fivebrane of M -theory. We show that the dynamics of the eleven-dimensional fivebrane can be obtained from the quantization of a “small membrane” that is confined to a single fivebrane and which moves with the speed of light. This shows that the eleven-dimensional fivebrane has an interpretation as a D -brane of an open supermembrane as has recently been proposed by Strominger and Townsend. We briefly discuss the boundary dynamics of an infinitely extended planar membrane that is stretched between two parallel fivebranes.
Bond Refunding with Stochastic Interest Rates

The bond refunding problem is formulated as a multiperiod decision process in which future interest rates are determined by a Markovian stochastic process. It is assumed that a single bond is to be outstanding at a given time. Given the future requirements for debt financing, the decision maker must decide whether to keep his current bond or to refund by issuing a new bond at the current market interest rates. Over a finite planning horizon, the structure of policies which minimize expected total discounted costs is studied.
Predicted performance of an induction linac driven FEL amplifier designed for radar applications at 94 GHz

Abstract The saturated performance of an induction linac driven FEL operating at 94 GHz with peak microwave powers in excess of 2 GW is evaluated using a self-consistent 3D waveguide mode-particle interaction code. The code includes the effect of ac longitudinal space charge and dc transverse space charge with the resulting prediction that operation is not possible below 2.5 MeV with a 2 kA beam and 10 cm wiggler. A design based around a 4 MeV beam predicts peak power in excess of 2.4 GW over a 10% bandwidth with output phase varying linearly with frequency.
CameraCast : Flexible Access to Remote Video Sensors

New applications like remote surveillance and online environmental or traffic monitoring are making it increasingly important to provide flexible and protected access to remote video sensor devices. Current systems use application-level codes like web-based solutions to provide such access. This requires adherence to user-level APIs provided by such services, access to remote video information through given application-specific service and server topologies, and that the data being captured and distributed is manipulated by third party service codes. CameraCast is a simple, easily used system-level solution to remote video access. It provides a logical device API so that an application can identically operate on local vs. remote video sensor devices, using its own service and server topologies. In addition, the application can take advantage of API enhancements to protect remote video information, using a capability-based model for differential data protection that offers fine grain control over the information made available to specific codes or machines, thereby limiting their ability to violate privacy or security constraints. Experimental evaluations of CameraCast show that the performance of accessing remote video information approximates that of accesses to local devices, given sufficient networking resources. High performance is also attained when protection restrictions are enforced, due to an efficient kernel-level realization of differential data protection.
Keith R. Porter and the first electron micrograph of a cell

Keith R. Porter died on 2 May 1997. Although he was especially renowned for the work on cell structure recounted here, his impact on cell biology was not confined to the early electron-microscopic studies of ultrastructure. To many, he was the father of cell biology, who helped establish many of the enduring institutions and ideas in the field. He had great biological intuition and feeling for a wide range of organisms and was greatly concerned with problems of cell shape and movement. He used ultrastructure and simple physiological or biochemical experiments to infer functional activities for cell organelles, including not only the endoplasmic reticulum, which he named, but the sarcoplasmic reticulum and T-tubules of muscle cells, microtubules, cilia, coated vesicles and more. He also pioneered cell studies with the high-voltage electron microscope, which led him to the idea of structural integration in the cell cytoplasm, an idea that is only now being pursued with success.
Decomposing terms of trade fluctuations in Ethiopia

This paper provides a technique to decompose short-run fluctuations in the terms of trade. Using Ethiopia as an example, the authors decompose the commodity terms of trade into various components to measure the impact of price and volume shifts as well as export diversification. The authors use monthly data from the past decade, including periods during the global food and financial crises. The findings suggest that diversification out of traditional coffee exports to other export commodities successfully mitigated a terms of trade shock. Continued export diversification will be beneficial. This paper is structured as follows: section one gives introduction; section two gives an overview of Ethiopian trade patterns; section three discusses the methodology of terms of trade decomposition; section four presents the empirical results; and section five concludes.
Optimum design of composite shells subject to natural frequency constraints

Abstract A technique for the optimum (minimum weight) design of a composite shell subject to constraints on its natural frequencies is presented. The optimization problem is posed as a general mathematical programming problem in which one or more of the inequality constraints involves the shell natural frequencies, which must be evaluated numerically during the optimization. For this reason, a method for numerically evaluating the natural frequencies of composite shells is also presented. The method is based upon the finite element method of structural analysis and Rayleigh's principle. Because the element used is applicable to anisotropic shells of arbitrary shape, the method is very general. By using Rayleigh's principle, the necessity of assembling overall mass and stiffness matrices for the shell is eliminated. The optimization is performed by nondimensionalizing the mathematical programming problem and using the penalty function method of Fiacco and McCormick to transform the problem to a sequence of unconstrained minimizations having solutions which converge to the solution of the original (constrained) problem. The unconstrained minimizations are performed using the variable metric method of Fletcher and Powell. Derivatives of the nondimensional frequency constraints are evaluated numerically using difference equations. The frequency calculation method is demonstrated by calculating the fundamental frequency for the transverse vibration mode of a multilayered cylindrical shell with fixed overall geometry and variable composite geometry. Results indicate that the frequency increases with increasing fiber orientation angle, fiber volume fraction, or lamina thickness. The optimization technique is demonstrated by minimizing the weight of the shell discussed above subject to a constraint on its fundamental transverse frequency. The design variables are the fiber orientation angle, the fiber volume fraction, and the lamina thickness. Results are presented and explained in terms of the physical aspects of the problem.
Dielectric relaxation from a network of charged defects in dilute CeO2:Y2O3 solid solutions

Abstract Solid solutions of Y 2 O 3 in CeO 2 are examined by the thermal depolarization (or ITC) method of dielectric relaxation. For concentrations ≤1 m/o Y 2 O 3 , two peaks are observed. The lower temperature peak, Peak 1, is interpreted as due to the relaxation of nn YV O pairs (where V O = oxygen vacancy), and is analogous to the well-known CaV O pair obtained with Ca 2+ doping. The upper peak, Peak 2, on the other hand, is a broad peak whose position is a function of concentration. It is not due to simple dipoles, but originates in the network of alternately charged (YV O · pairs and isolated Y' defects by redistribution of vacancies.
ACM SIGSOFT Impact Paper Award 2012: Systematic Software Testing: The Korat Approach

At ISSTA 2002, the three authors (then Ph.D. students) published the paper "Korat: Automated Testing Based on Java Predicates", which won one of the first ACM SIGSOFT Distinguished paper awards. In 2012, the paper won the ACM SIGSOFT Impact Paper Award. The authors briefly recount the motivation behind Korat research, the ideas presented in the original paper, and some work it inspired.
My favourite is not on the shelf: effects of the revealed-preference bundle on consumers' stated choice

SummaryBased on a conjoint choice experiment relating to canola oil in Japan, this article establishes and tests the impacts of various measures of reference dependence on choice. Results show that although reference dependence may be defined within choice tasks as a type of choice complexity, a broader and more logical definition should be based on respondents' revealed-preference bundle. This broader definition allows for a richer representation and interpretation of behaviour. It is found that references may affect choices through different channels and that many of these effects are non-linear.
The Effect of Information Complexity on Analysts' Use of That Information

In this study I investigate the relation between information complexity and financial analysts' use of that information. I rank by complexity six tax‐law changes enacted by the Tax Reform Act of 1986, and then examine analysts' explicit forecasts of effective tax rates around those changes. I show that analysts' revisions of their forecasts of effective tax rates appear to impound the effects of the less complex tax‐law changes but not the more complex changes. Furthermore, as expected, if analysts assimilate less complex (but not more complex) information, the magnitude of the errors in their forecasts of effective tax rates increases with the effects of the more complex tax‐law changes, but is unrelated to the less complex changes. Taken together, these results indicate that analysts assimilate less complex information to a greater extent than they assimilate more complex information. Either analysts' abilities to incorporate specific information into their forecasts is a decreasing function of the comp...
High Temperature VLE for the Benzene−Ethylbenzene System

We used a continuous flow apparatus designed for vapor−liquid equilibrium (VLE) data measurements at high temperatures up to 400 °C, previously used to measure VLE data along three isotherms for the tetralin−quinoline system. In this work, the apparatus was slightly modified for measurements of four high-temperature (180 °C, 210 °C, 250 °C, 280 °C) VLE isotherms for the benzene−ethylbenzene system. The data were successfully tested for thermodynamic consistency by using the area test.
A dictionary for voting paradoxes

Abstract A Sonnenschein-Mantel-Debreu kind of characterization is found for positional voting procedures. Namely, for n⩾2 candidates, once the voting procedures and a profile are specified, the rankings of all possible subsets of candidates are uniquely determined. By varying over all profiles, one obtains a dictionary of all possible coordinated election outcomes. This is done for all positional voting procedures. As with excess demand functions, anything can happen; voting paradoxes can be very complicated. Only Borda's method avoids many paradoxes. Use of this dictionary is illustrated by significantly extending several well-known paradoxes and by obtaining new results about runoff and agenda elections, strategic behavior, etc.
The limitations of nice mutually unbiased bases

Mutually unbiased bases of a Hilbert space can be constructed by partitioning a unitary error basis. We consider this construction when the unitary error basis is a nice error basis. We show that the number of resulting mutually unbiased bases can be at most one plus the smallest prime power contained in the dimension, and therefore that this construction cannot improve upon previous approaches. We prove this by establishing a correspondence between nice mutually unbiased bases and abelian subgroups of the index group of a nice error basis and then bounding the number of such subgroups. This bound also has implications for the construction of certain combinatorial objects called nets.
Testing ultrafast mode-locking at microhertz relative optical linewidth

We report new limits on the phase coherence of the ultrafast mode-locking process in an octave-spanning Ti:sapphire comb. We find that the mode-locking mechanism correlates optical phase across a full optical octave with less than 2.5 μHz relative linewidth. This result is at least two orders of magnitude below recent predictions for quantum-limited individual comb-mode linewidths, verifying that the mode-locking mechanism strongly correlates quantum noise across the comb spectrum.
Assumed Density Filter with Application to Homing Missile Guidance

A maximum likelihood estimation method is developed for a class of problems where the dynamics are linear and the measurement function is nonlinear. In this method, called the "assumed density filter,' the form of the conditional probability density function is selected to be a function of a finite number of quantities. These quantities, which describe the approximate shape of conditional probability density function around the mode, are propagated through each measurement interval. At the measurement, the conditional probability density function is updated using Bayes theorem, and its mode, computed numerically, is defined to be the best estimate of the state. The posteriori conditional probability density function is then approximated by a Taylor series expansion about its mode to preserve the assumed functional form. The numerical results for a target-intercept problem indicate that the assumed density filter is superior to the extended Kalman filter. However, the assumed density filter has a negative range bias. It is analytically proved, with some approximations, that the maximum likelihood range estimates are smaller than the mean range estimates.
Formation of singularity for compressible viscoelasticity

Abstract The formation of singularity and breakdown of classical solutions to the three-dimensional compressible viscoelasticity and inviscid elasticity are considered. For the compressible inviscid elastic fluids, the finite-time formation of singularity in classical solutions is proved for certain initial data. For the compressible viscoelastic fluids, a criterion in term of the temporal integral of the velocity gradient is obtained for the breakdown of smooth solutions.
Diastereodifferentiation in intramolecular cyclopropanations of chiral secondary allylic diazoacetates

Abstract Intramolecular cyclopropanations of diastereomeric, secondary allylic diazoacetates were carried out in the presence of an achiral copper catalyst, Cu(TBS)2, and the chiral rhodium catalysts Rh2[5(S)-MEPY]4 and Rh2[5(R)-MEPY]4 to give diastereomeric cyclopropyl lactones in ratios that varied with catalysts and stereochemistry of the starting material.
Optimal Foresighted Multi-User Wireless Video

Recent years have seen an explosion in wireless video communication systems. Optimization in such systems is crucial – but most existing methods intended to optimize the performance of multi-user wireless video transmission are inefficient. Some works (e.g., Network Utility Maximization (NUM)) are myopic: they choose actions to maximize instantaneous video quality while ignoring the future impact of these actions. Such myopic solutions are known to be inferior to foresighted solutions that optimize the long-term video quality. Alternatively, foresighted solutions such as rate-distortion optimized packet scheduling focus on single-user wireless video transmission, while ignoring the resource allocation among the users. In this paper, we propose a general framework of foresighted resource allocation among multiple video users sharing a wireless network. Our framework allows each user to flexibly choose individual cross-layer strategies. Our proposed resource allocation is optimal in terms of the total payoff (e.g., video quality) of the users. A key challenge in developing foresighted solutions for multiple video users is that the users' decisions are coupled. To decouple the users' decisions, we adopt a novel dual decomposition approach, which differs from the conventional optimization solutions such as NUM, and determines foresighted policies. Specifically, we propose an informationally-decentralized algorithm in which the network manager updates state- and user-dependent resource “prices” (i.e., the dual variables associated with the resource constraints), and the users make individual packet scheduling decisions based on these prices. Because a priori knowledge of the system dynamics is almost never available at run-time, the proposed solution can learn online while performing the foresighted optimization. Simulation results show 7 dB and 3 dB improvements in Peak Signal-to-Noise Ratio (PSNR) over myopic solutions and existing foresighted solutions, respectively.
A Decision analysis to determine the appropriate treatment for low-risk myelodysplastic syndromes.

BACKGROUND. The myelodysplastic syndromes (MDS) are divided into low-risk and high-risk diseases. Predictive models for response to growth factors (GF) have been developed based on red blood cell transfusion needs and erythropoietin levels. For low-risk MDS the optimal initial therapy (GF vs nongrowth factor [NGF] therapies, including differentiation and immunomodulatory agents) based on response rates to NGF and GF and survival, has not been defined. METHODS. A Markov decision analysis was performed on 799 low-risk MDS patients treated with either GF or NGF to determine the appropriate initial therapy. The treatment strategies analyzed included initial GF or NGF therapies, assuming 3 different states: Patients were either in the good GF predictive group (low transfusion needs and low erythropoietin levels), intermediate, or the poor GF predictive group (high transfusion needs and high erythropoietin levels). RESULTS. In the good GF predictive group, initial therapy with GF improved survival compared with NGF therapies at 3.38 years vs 2.57 years for a typical MDS patient. The advantage of GF to NGF was lost when NGF therapies produced a response in ≥46% of patients. In the intermediate or poor GF predictive groups, NGF maximized survival, provided response rates for NGF were >14% and 4%, respectively, for each predictive group. Quality of life adjustment did not alter the preferred strategy. CONCLUSIONS. Modeling estimates suggest that patients who fall into a good GF predictive group should almost always receive GF initially, whereas those in intermediate and poor predictive groups should almost always be treated with NGF. Cancer 2007 © 2007 American Cancer Society.
Sections of the Difference Body

Let K be an n -dimensional convex body. Define the difference body by K-K= { x-y | x,y ∈ K }. We estimate the volume of the section of K-K by a linear subspace F via the maximal volume of sections of K parallel to F . We prove that for any m -dimensional subspace F there exists x ∈ \bf R n , such that \( \mbox{\rm vol} ((K-K) \cap F) \le C^m \left ( \min \left ( \frac{n}{m}, \sqrt{m} \right ) \right )^m \cdot \mbox{\rm vol} (K \cap (F+x)),\) for some absolute constant C . We show that for small dimensions of F this estimate is exact up to a multiplicative constant.