cssi/SciSciGPT-SciSciNet huggingface dataset:
Robust Stability of Closed-Loop Systems Resulting From Nonsequential MIMO-QFT Design

Considered in this paper is the question of whether a compensator realized by the MIMO-QFT nonsequential method robustly stabilizes the entire plant family. In order to establish out results, first the classic small gain theorem for robust stability is modified to allow uncertain plant families with poles arbitrarily crossing the imaginary axis, or equivalently, plants in which the number of unstable poles does not remain fixed over all uncertainties. The conventional assumption that the number of unstable poles remain fixed over all uncertainties can be quite restrictive, especially, in the case of plants with structured uncertainties. It is shown that to assure robust stability of the closed loop, resulting from the MIMO-QFT nonsequential approach, one more requirement must be added to the procedure. The needed extra condition can be quite naturally incorporated during the execution of the nonsequential technique. As a result, the proposed condition does not significantly alter the basic MIMO-QFT nonsequential procedure.
Second quantization of the Wilson loop

Treating the QCD Wilson loop as amplitude for the propagation of the first quantized particle, we develop the second quantization of the same propagation. The operator of the particle position \( \hat \chi _\mu \) (the endpoint of the “open string”) is introduced as a limit of the large N Hermitian matrix. We then derive the set of equations for the expectation values of the vertex operators (V(k 1)…V(k n )). The remarkable property of these equations is that they can be expanded at small momenta (less than the QCD mass scale), and solved for expansion coefficients. This provides the relations for multiple commutators of the position operator which can be used to construct this operator. We employ the noncommutative probability theory and find the expansion of the operator \( \hat \chi _\mu \) in terms of products of creation operators \( a_\mu ^\dag \). In general, there are some free parameters left in this expansion. In two dimensions we fix parameters uniquely from the symplectic invariance. The Fock space of our theory is much smaller than that of perturbative QCD, where the creation and annihilation operators were labelled by continuous momenta. In our case this is a space generated by d = 4 creation operators. The corresponding states are given by all sentences made of the four letter words. We discuss the implication of this construction for the mass spectra of mesons and glueballs.
MgBr2 · OEt2: A Lewis Acid Catalyst for the O- and N-Boc Protection of Phenols and Amines

AbstractMgBr2 · OEt2 efficiently catalyzes the O- and N-tert-butoxycarbonylation of functionalized phenols and amines. The presented procedure is operationally simple and done under solvent-free conditions.
Propagator matrices in elastic wave and vibration problems

The boundary value problems most frequently encountered in studies of elastic wave propagation in stratified media can be formulated in terms of a finite number of linear, first order, ordinary differential equations with variable coefficients. Volterra (1887) has shown that solutions to such a system of equations are conveniently represented by the product integral, or propagator, of the matrix of coefficients. In this paper we summarize some of the better known properties of propagators plus numerical methods for their computation. When the dispersion relation is some mth order minor of the integral matrix it is possible to deal with mth minor propagators so that the dispersion relation is a single element of the mth minor integral matrix. In this way one of the major sources of loss of numerical accuracy in computing the dispersion relation is avoided. Propagator equations for SH and for P‐SV waves are given for both isotropic and transversely isotropic media. In addition, the second minor propagator e...
Effects of state recovery on creep buckling under variable loading

Structural alloys embody internal mechanisms that allow recovery of state with varying stress and elevated temperature, i.e., they can return to a softer state following periods of hardening. Such material behavior is known to strongly influence structural response under some important thermomechanical loadings, for example, that involving thermal ratchetting. The influence of dynamic and thermal recovery on the creep buckling of a column under variable loading is investigated. The column is taken as the idealized (Shanley) sandwich column. The constitutive model, unlike the commonly employed Norton creep model, incorporates a representation of both dynamic and thermal (state) recovery. The material parameters of the constitutive model are chosen to characterize Narloy Z, a representative copper alloy used in thrust nozzle liners of reusable rocket engines. Variable loading histories include rapid cyclic unloading/reloading sequences and intermittent reductions of load for extended periods of time; these are superimposed on a constant load. The calculated results show that state recovery significantly affects creep buckling under variable loading. Structural alloys embody internal mechanisms that allow recovery of state with varying stress and time.
Statistical Variability and the Deterrent Effect of the Death Penalty

In a recent paper Donohue and Wolfers (DW specifically, that the estimated standard errors on the subset of his regressions that suggest a deterrent effect are downward biased due to autocorrelation. The method that D&W rely upon to adjust Zimmerman's standard errors is, however, potentially problematic, and is also only one of several methods to address the presence of autocorrelation. To this end, Zimmerman's original models are subjected to several parametric corrections for autocorrelation, all of which result in statistically significant estimates that are of the same magnitude to his original estimates. The paper also presents results obtained from an alternative model whose specification is motivated on theoretical and statistical grounds. These latter results also provide some evidence supporting a deterrent effect. Finally, the paper discusses D&W's use of randomization testing and their contention that executions are not carried out often enough to plausibly deter murders.
Rayleigh Scattering and Microwave Background Fluctuations

During the recombination epoch, cosmic background photons coupled not only to free electrons through Thompson scattering, but also to neutral hydrogen through Rayleigh scattering. This latter is a ~2% effect for photons near the peak of the photon energy distribution at z = 800 and a ~0.2% effect at z = 1100. Including Rayleigh scattering in the calculation reduces Silk damping at fixed redshift, alters the position of the surface of last scattering, and alters the propagation of acoustic waves. We estimate the amplitude of these effects. For the Microwave Anisotropy Probe (MAP), Rayleigh scattering increases the anisotropy spectrum by 0.1% at the most. For the highest frequencies of the Planck Surveyor, the effects of Rayleigh scattering are much more dramatic (decreasing the anisotropy spectrum by 3% at ν ~ 550 GHz and multipole number l ~ 1000). The relative difference between the spectra of low and high frequencies is imposed by an oscillation with a function of multipole l, and the oscillation amplitude is up to 0.5% between 100 and 550 GHz. Rayleigh scattering also slows the decoupling between radiation and matter, but the effect is undetectably small.
ARTIFICIAL BOUNDARY CONDITIONS FOR MODEL UPDATING AND DAMAGE DETECTION

Abstract The updating of finite-element models commonly makes use of measured modal parameters. The number of modal parameters measured in a typical modal test is small, while the number of model parameters to be adjusted can be large. In this paper, it is shown that the natural frequencies for the structure under a variety of boundary conditions are available from any square, spatially incomplete frequency response function data, without any actual physical alteration of the boundary conditions, hence the term ‘artificial boundary conditions’. This approach can provide potentially a large number of additional and distinct mode frequencies from the same modal test. The simplest example of this approach is that the driving-point antiresonance frequencies correspond to the natural frequencies obtained from the structure with the driving-point degree of freedom constrained to ground. This result is developed generally for multiple measured points, and is shown to be related to previous results concerning omitted coordinate systems and spatially incomplete test data. The approach is applied to sensitivity-based model updating and damage detection.
Some flow characteristics of conventional and tapered high pressure drop simulated seals

The leak rates through shaft seals with large pressure drops were simulated using gaseous hydrogen, or nitrogen flowing through an annulus with a nonrotating centerbody. The flows were choked. For concentric or eccentric position of the rotor and parallel or convergent tapered flow passages, data and analysis revealed that mass flux or leak rate can be determined from a relation whose normalizing parameters depend on the thermodynamic critical constants of the working fluid and an average flow area expressed in terms of the inlet and exit cross-sectional areas. Using these normalized relations, the flow data for parallel and three convergent tapered shaft seal configurations are in good agreement. Generalization to any simple gas or gas mixture is implied and demonstrated.
Efficient coupling of 527 nm laser beam power to a long scalelength plasma

We experimentally demonstrate that application of laser smoothing schemes including smoothing by spectral dispersion (SSD) and polarization smoothing (PS) increases the intensity range for efficient coupling of frequency doubled (527 nm) laser light to a long scalelength plasma with n c /n er = 0.14 and T e = 2 keV.
Degradation Issues in Solid Oxide Cells During High Temperature Electrolysis

Idaho National Laboratory (INL) is performing high-temperature electrolysis (HTE) research to generate hydrogen using solid oxide electrolysis cells (SOECs). The project goals are to address the technical and degradation issues associated with the SOECs. This paper provides a summary of ongoing INL and INL-sponsored activities aimed at addressing SOEC degradation. These activities include stack testing, post-test examination, degradation modeling, and issues that need to be addressed in the future. Major degradation issues relating to solid oxide fuel cells (SOFC) are relatively better understood than those for SOECs. Some of the degradation mechanisms in SOFCs include contact problems between adjacent cell components, microstructural deterioration (coarsening) of the porous electrodes, and blocking of the reaction sites within the electrodes. Contact problems include delamination of an electrode from the electrolyte, growth of a poorly (electronically) conducting oxide layer between the metallic interconnect plates and the electrodes, and lack of contact between the interconnect and the electrode. INL’s test results on HTE using solid oxide cells do not provide clear evidence as to whether different events lead to similar or drastically different electrochemical degradation mechanisms. Post-test examination of the SOECs showed that the hydrogen electrode and interconnect get partially oxidized and become nonconductive. This is most likely caused by the hydrogen stream composition and flow rate during cooldown. The oxygen electrode side of the stacks seemed to be responsible for the observed degradation because of large areas of electrode delamination. Based on the oxygen electrode appearance, the degradation of these stacks was largely controlled by the oxygen electrode delamination rate. Virkar et al. [19–22] have developed a SOEC model based on concepts in local thermodynamic equilibrium in systems otherwise in global thermodynamic nonequilibrium. This model is under continued development. It shows that electronic conduction through the electrolyte, however small, must be taken into account for determining local oxygen chemical potential within the electrolyte. The chemical potential within the electrolyte may lie out of bounds in relation to values at the electrodes in the electrolyzer mode. Under certain conditions, high pressures can develop in the electrolyte just under the oxygen electrode (anode)/electrolyte interface, leading to electrode delamination. This theory is being further refined and tested by introducing some electronic conduction in the electrolyte.Copyright © 2010 by ASME
Oxidative photoredox catalysis: mild and selective deprotection of PMB ethers mediated by visible light

Herein we report an advancement in the application of visible light photoredox catalysts in the oxidation of electron-rich arenes resulting in the selective deprotection of para-methoxybenzyl (PMB) ethers. This method is highlighted by excellent functional group tolerance, protecting group orthogonality, mild reaction conditions and avoidance of stoichiometric redox byproducts.
A comparison between BIMOS device types

This paper deals with the design and comparison of three types of BIMOS transistors (cascade, cascode, and parallel combinations of MOSFET and bipolar transistors). The first section of the paper presents a technique for accurately determining the overall device I-V relations for the cascade (Darlington) combination based on the area ratio for the MOSFET and bipolar transistors. From this, one sees that the optimum area ratio varies from 1.5 for 700-V devices to 0.2 for 80- V devices. The second section of the paper deals with the design and comparison of the cascode and parallel device types. In these cases, no optimum area ratio based solely on device conduction exists and the device design and comparison is based on achieving the maximum current density limited by keeping the power dissipation to under 100 W/ cm2. Included in this analysis are losses due to conduction as well as switching. The results show that a 0.5 area ratio (MOSFET to bipolar transistor) is optimum for the cascode (series) combination and a 0.3 ratio is a good compromise for the parallel combination. The last section of the paper shows an overall comparison of all of the BIMOS device types together with the MOSFET and the bipolar transistor.
On symplectic fillings

In this note we make several observations concerning symplectic fillings. In particular we show that a (strongly or weakly) semi-fillable contact structure is fillable and any filling embeds as a symplectic domain in a closed symplectic manifold. We also relate properties of the open book decomposition of a contact manifold to its possible fillings. These results are also useful in showing the contact Heegaard Floer invariant of a fillable contact structure does not vanish [28] and property P for knots [18].
Potential Structures and Particle Acceleration on Auroral Field Lines.

Observations of plasmas and electric field activity within regions of auroral particle acceleration have verified the existence of electric fields with components parallel to the magnetic field over large altitude regions. Evidence is presented which indicates that small-ampliatude double layers along the auroral magnetic field lines may provide a mechanism for the maintenance of auroral ion potential. Evidence is also presented of downward-directed parallel electric fields along the magnetic field lines in the return current region. It is suggested that the downward electric fields may have significant effects on ion trajectories, and further theoretical investigation of the effects of downward parallel electric fields on ion conic formation is recommended.
Chemical Biology of Epothilones

Only a few months after the disclosure of the absolute configuration of epothilones A (R=H, see picture on the right) and B (R=Me) the first total syntheses of these natural products were reported. Interest intensified with the realization of their potential as anticancer agents with a taxol-like mechanism of action. In addition to describing the most important total syntheses and biological properties of the naturally occurring epothilones A-E, this review also provides a systematic overview of numerous epothilone analogues that have been modified in the A-D regions in order to obtain information about structure-activity relationships.
Collective Behavior in Solid-State Plasmas

The conditions for the existence of plasma wave instabilities in the plasma formed by the electrons and holes in semiconductors are discussed. The dispersion relations for both the high-frequency optical mode in which electrons and holes move out of phase, and the low-frequency acoustic mode in which electrons and holes move in phase are calculated. Growing acoustic waves are shown to occur for a sufficiently large relative drift velocity of the electrons and holes, and the boundary between growing and damped waves is determined for various electron-hole temperature ratios. Growth rates are calculated for several cases of interest; when the influence of impurity and phonon scattering on the electron-hole behavior is taken into account it is concluded that InSb is perhaps the most promising semiconductor in which to observe such instabilities. An investigation of the hole and electron temperatures and the relative electron- hole drift velocity as a function of field strength is carried out for InSb. It is shown that moderate field strengths (~l00 v/cm) suffice to produce electronhole drifts of the required order of magnitude for the observation of plasma wave instability; however, the scattering mechanisms present are sufficiently effective that it appears marginal whether the other conditionmore » (long hole relaxation times) necessary for the observation of the plasma wave instability is achievable in practice. Conditions for the occurrence of similar plasma wave instabilities in semimetals are analyzed briefly. (auth)« less
Girvin–MacDonald–Platzman collective mode at general filling factors: magneto-roton minimum at half-filled Landau level

Abstract The single mode approximation has proved useful for the excitation spectrum at ν=1/3. We apply it to general fractions and find that it predicts n magneto-roton minima in the dispersion of the Girvin–MacDonald–Platzman collective mode for the fractional quantum Hall states at ν=n/(2n+1), and one magneto-roton minimum for both the composite Fermi sea and the paired composite fermion state. Experimental relevance of the results will be considered.
Discussion of ‘limited attention, information disclosure, and financial reporting’

Abstract This paper discusses Hirshleifer and Teoh's modeling and analysis of “inattentive investors”, stock price valuation, and accounting recognition rules and disclosures. The paper derives many plausible empirical predictions from an equilibrium model in which some investors do not process information “fully” or correctly. My discussion focuses on the underlying features of the analysis that drive these results, and speculates as to the robustness of key results. In particular, the systematic “mis-pricing” that persists for long periods of time in the model is very controversial.
The k -Steiner Ratio in Graphs

A Steiner minimum tree (SMT) is the shortest-length tree in a metric space interconnecting a set of points, called the regular points, possibly using additional vertices. A k-size Steiner minimum tree (kSMT) is one that can be split into components where all regular points are leaves and all components have at most k leaves. The k-Steiner ratio, $\rho_{k}$, is the infimum of the ratios SMT/kSMT over all finite sets of regular points in all possible metric spaces, where the distances are given by a complete graph. Previously, only $\rho_{2}$ and $\rho_{3}$ were known exactly in graphs, and some bounds were known for other values of k. In this paper, we determine $\rho_{k}$ exactly for all k. From this we prove a better approximation ratio for the Steiner tree problem in graphs.
Native Competition and Low-Skilled Immigrant Inflows

This paper demonstrates that immigration decisions depend on local labor market conditions by documenting the change in low-skilled immigrant inflows in response to supply increases among the US-born. Using pre-reform welfare participation rates as an instrument for changes in native labor supply, I find that immigrants competing with native entrants systematically prefer cities with smaller supply shocks. The extent of the response is substantial: for each native woman working due to reform, 0.5 fewer female immigrants enter the local labor force. These results provide direct evidence that international migration flows tend to equilibrate returns across US local labor markets.
Random Oxford Graphs

Inspired by a concept in comparative genomics, we investigate properties of randomly chosen members of G1(m,n,t), the set of bipartite graphs with m left vertices, n right vertices, t edges, and each vertex of degree at least one. We give asymptotic results for the number of such graphs and the number of (i,j) trees they contain. We compute the thresholds for the emergence of a giant component and for the graph to be connected.
Concepts for insertion devices that will produce high-quality synchrotron radiation

Abstract A simple analysis is presented that shows what effect the two major construction tolerances have on the field distribution in undulators, and it is shown that the consequential effects on the synchrotron radiation spectrum depend strongly on the type of undulator. A number of new conceptual undulator designs are described that allow electromagnetic correction of the field distribution in these undulators.
Young, Low-Mass Brown Dwarfs with Mid-Infrared Excesses

We have combined new I, J, H, and Ks imaging of portions of the Chamaeleon II, Lupus I, and Ophiuchus star-forming clouds with 3.6-24 μm imaging from the Spitzer legacy program "From Molecular Cores to Planet-Forming Disks" to identify a sample of 19 young stars, brown dwarfs, and sub-brown dwarfs showing mid-infrared excess emission. The resulting sample includes sources with luminosities of 0.5 > log(L*/L☉) > -3.1. Six of the more luminous sources in our sample have been previously identified by other surveys for young stars and brown dwarfs. Five of the sources in our sample have nominal masses that are at or below the deuterium-burning limit (12MJ). Over three decades in luminosity, our sources have an approximately constant ratio of excess to stellar luminosity. We compare our observed spectral energy distributions (SEDs) to theoretical models of a central source with a passive irradiated circumstellar disk and test the effects of disk inclination, disk flaring, and the size of the inner disk hole on the strength/shape of the excess. The observed SEDs of all but one of our sources are well fitted by models of flared and/or flat disks.
Iron-rich Ejecta in the Supernova Remnant DEM L71

Chandra X-ray observations of DEM L71, a supernova remnant (SNR) in the Large Magellanic Cloud (LMC), reveal a clear double-shock morphology consisting of an outer blast-wave shock surrounding a central bright region of reverse-shock-heated ejecta. The abundances of the outer shock are consistent with LMC values, while the ejecta region shows enhanced abundances of Si, Fe, and other species. However, oxygen is not enhanced in the ejecta; the Fe/O abundance ratio there is 5 times the solar ratio. Based on the relative positions of the blast-wave shock and the contact discontinuity in the context of SNR evolutionary models, we determine a total ejecta mass of ~1.5 M☉. Ejecta mass estimates based on emission measures derived from spectral fits are subject to considerable uncertainty because of the lack of knowledge of the true contribution of hydrogen continuum emission. Maximal mass estimates, i.e., assuming no hydrogen, result in 1.5 M☉ of Fe and 0.24 M☉ of Si. Under the assumption that an equal quantity of hydrogen has been mixed into the ejecta, we estimate 0.8 M☉ of Fe and 0.12 M☉ of Si. These characteristics support the view that in DEM L71, we see Fe-rich ejecta from a Type Ia supernova several thousand years after explosion.
Rapid, highly diastereoselective addition of dialkylzinc reagents to atropisomeric 2-formyl arylamides

We have observed that dialkylzinc reagents add to atropisomeric 2-formyl arylamides many times faster than they react with other substituted benzaldehyde derivatives. Additionally, with diethylzinc the products were formed with very high diastereoselectivity, affording the syn product (d.r. greater than 95:5), except in one case where epimerization of the product is rapid. In contrast, Grignard and trialkylaluminum reagents afforded the anti diastereomers, with diminished stereoselectivity and formation of reduction products.
The Effect of Dealumination on Zeolite-Supported Ru Catalysts

Abstract The physical and catalytic properties of a series Ru/dealuminated Y-zeolite catalysts prepared by ion exchange have been investigated in order to better understand the effect of the Si/Al ratio of a zeolite on the catalytic properties of a supported metal. Dealumination up to 52% was shown not to have affected the crystallinity of the zeolite. The reduced Ru catalysts exhibited increased metal dispersions, as measured by H2 chemisorption, with increased zeolite dealumination. Turnover frequency (TOF) for CO hydrogenation vs Si/Al ratio showed a volcano shape. Maximum TOF occurred at a Si/Al ratio of about 5. While the overall product distribution was unaffected by Si/Al ratio, an increase in the selectivity for iso-C4 with increasing dealumination indicated that secondary reactions of the F-T primary products were enhanced by the presence of stronger acid sites. It is well known that the concentration of acid sites in a dealuminated Y-zeolite decreases with increasing Si/Al ratio, while the strength of the acid sites increases and reaches a maximum for Si/Al ≍ 4.5. Since overall chain growth probability was not apparently affected by dealumination of the zeolite support, it is suggested that the increase in overall activity for CO hydrogenation on the dealuminated Ru catalysts may have been primarily due to an enhancement in secondary reactions as a result of the increase in acid strength lessening readsorption of olefinic primary products on Ru CO hydrogenation sites.
Growth factor regulation of proliferation and survival of multipotential stromal cells

Multipotential stromal cells (MSCs) have been touted to provide an alternative to conservative procedures of therapy, be it heart transplants, bone reconstruction, kidney grafts, or skin, neuronal and cartilage repair. A wide gap exists, however, between the number of MSCs that can be obtained from the donor site and the number of MSCs needed for implantation to regenerate tissue. Standard methods of MSC expansion being followed in laboratories are not fully suitable due to time and age-related constraints for autologous therapies, and transplant issues leave questions for allogenic therapies. Beyond these issues of sufficient numbers, there also exists a problem of MSC survival at the graft. Experiments in small animals have shown that MSCs do not persist well in the graft environment. Either there is no incorporation into the host tissue, or, if there is incorporation, most of the cells are lost within a month. The use of growth and other trophic factors may be helpful in counteracting these twin issues of MSC expansion and death. Growth factors are known to influence cell proliferation, motility, survival and morphogenesis. In the case of MSCs, it would be beneficial that the growth factor does not induce differentiation at an early stage since the number of early-differentiating progenitors would be very low. The present review looks at the effect of and downstream signaling of various growth factors on proliferation and survival in MSCs.
Linearly Parameterized Bandits

We consider bandit problems involving a large (possibly infinite) collection of arms, in which the expected reward of each arm is a linear function of an r-dimensional random vector Z ∈ Rr, where r ≥ 2. The objective is to minimize the cumulative regret and Bayes risk. When the set of arms corresponds to the unit sphere, we prove that the regret and Bayes risk is of order Θ(r √T), by establishing a lower bound for an arbitrary policy, and showing that a matching upper bound is obtained through a policy that alternates between exploration and exploitation phases. The phase-based policy is also shown to be effective if the set of arms satisfies a strong convexity condition. For the case of a general set of arms, we describe a near-optimal policy whose regret and Bayes risk admit upper bounds of the form O(r √T log3/2T).
An Induction Principle and Pigeonhole Principles for K-Finite Sets

We establish a course-of-values induction principle for K-finite sets in intuitionistic type theory. Using this principle, we prove a pigeonhole principle conjectured by Benabou and Loiseau. We also comment on some variants of this pigeonhole principle. ?
Hochschild cohomology and graded Hecke algebras

We develop and collect techniques for determining Hochschild cohomology of skew group algebras S(V)#G and apply our results to graded Hecke algebras. We discuss the explicit computation of certain types of invariants under centralizer subgroups, focusing on the infinite family of complex reflection groups G(r,p,n) to illustrate our ideas. Resulting formulas for Hochschild two-cocycles give information about deformations of S(V)#G and, in particular, about graded Hecke algebras. We expand the definition of a graded Hecke algebra to allow a nonfaithful action of G on V, and we show that there exist nontrivial graded Hecke algebras for G(r, 1, n), in contrast to the case of the natural reflection representation. We prove that one of these graded Hecke algebras is equivalent to an algebra that has appeared before in a different form.
Cognitive improvement despite minimal arachnoid cyst decompression

There are relatively few reports that evaluate the cognitive functions of patients with arachnoid cysts. Presumably, these 'silent cysts' are regarded as incidental findings with no functional significance. Although postoperative clinical improvement is well documented in patients with significant reduction in cystic volume, the current report describes a patient who underwent cystoperitoneal shunting due to mass effect, with minimal postoperative decompression. Neuropsychological testing indicated significant cognitive improvement in verbal learning, memory, visual-perceptual abilities, constructional skills, conceptual shifting, and psychomotor speed after shunt placement, despite marginal evidence of decompression. These findings suggest that (1) significant cognitive changes can occur in these patients, despite minimal postoperative regression of the lesion, (2) cognitive measures may provide an alternative, functional index of outcome efficacy, and (3) reliance on traditional outcome measures (i.e. anatomical decompression or resolution of clinical symptoms) may underestimate the efficacy of surgical intervention for these patients.
Simplifications and speedups of the pseudoflow algorithm

The pseudoflow algorithm for solving the maximum flow and minimum cut problems was devised in Hochbaum (2008). The complexity of the algorithm was shown in (2008) to be O(nm log n). Chandran and Hochbaum, (2009) demonstrated that the pseudoflow algorithm is very efficient in practice, and that the highest label version of the algorithm tends to perform best. Here, we improve the running time of the highest label pseudoflow algorithm to O(n3) using simple data structures and to O(nm log (n2/m)) using the dynamic trees data structure. Both these algorithms use a new form of Depth-First-Search implementation that is likely to be fast in practice as well. In addition, we give a new simpler description of the pseudoflow algorithm by relating it to the simplex algorithm as applied to the maximum preflow problem defined here. The interpretation of the generic pseudoflow algorithm as a simplex-like algorithm for the maximum preflow problem motivates the pseudoflow algorithm and highlights differences between the pseudoflow algorithm and the preflow-push algorithm of Goldberg and Tarjan. © 2012 Wiley Periodicals, Inc. NETWORKS, 2013 © 2013 Wiley Periodicals, Inc.
ELECTRON BEAM STUDY OF SILICIDE SCHOTTKY DIODES.

Abstract An electron-beam-induced voltage (EBIV) technique has been developed to measure the barrier height of Schottky diodes. The principle of this technique is described and is compared with the conventional electron-beam-induced current (EBIC) technique. Applications of both techniques are illustrated in a study of composite silicide Schottky diodes with mixed high and low barrier areas formed using bilayer and co-evaporated PdTi and PtTi films on silicon substrates. The difficulty of using EBIC for quantitative studies of diode characteristics is discussed and contrasted with the advantages of the EBIV technique. The extension of the EBIV technique to contactless measurements of barrier height variation with good lateral resolution is described.
System support for bandwidth management and content adaptation in internet applications

This paper describes the implementation and evaluation of an operating system module, the Congestion Manager (CM), which provides integrated network flow management and exports a convenient programming interface that allows applications to be notified of, and adapt to, changing network conditions. We describe the API by which applications interface with the CM, and the architectural considerations that factored into the design. To evaluate the architecture and API, we describe our implementations of TCP; a streaming layered audio/video application; and an interactive audio application using the CM, and show that they achieve adaptive behavior without incurring much end-system overhead. All flows including TCP benefit from the sharing of congestion information, and applications are able to incorporate new functionality such as congestion control and adaptive behavior.
Latent Factor Models for Density Estimation

Although discrete mixture modelling has formed the backbone of the literature on Bayesian density estimation, there are some well-known disadvantages. As an alternative to discrete mixtures, we propose a class of priors based on random nonlinear functions of a uniform latent variable with an additive residual. The induced prior for the density is shown to have desirable properties, including ease of centring on an initial guess, large support, posterior consistency and straightforward computation via Gibbs sampling. Some advantages over discrete mixtures, such as Dirichlet process mixtures of Gaussian kernels, are discussed and illustrated via simulations and an application.
Transient response of gallium arsenide and silicon solar cells under laser pulse

Abstract Solar cells can be used as receivers in laser power beaming applications [1] . Power beamed to a photovoltaic array could power a satellite, an orbital transfer vehicle or a lunar base. Understanding solar cell response to the pulsed output of a free-electron laser (FEL) is important for evaluation of power-beaming applications. In this work we investigate the time response of gallium arsenide and silicon solar cells to a 25 ns monochromatic pulse input. The PC-1D computer code is used to analyze the cell current during and after the pulse for various conditions. For GaAs cells, current decay was studied at 511, 840 and 870 nm. Most of the results have been calculated for a peak intensity of 50 W cm −2 , which corresponds to roughly 500 suns peak concentration. Silicon cells have a longer minority carrier lifetime and weaker optical absorption, resulting in longer characteristic time constants. Si cell performance was studied at 900, 950 and 1060 nm wavelengths.
A look at what is (and isn’t) known about quasar broad line regions and how narrow-line Seyfert 1 galaxies fit in

Abstract The evidence is reviewed that the Broad Line Region (BLR) probably has two distinct components located at about the same distance from the central black hole. One component, BLR II, is optically-thick, low-ionization emission at least some of which arises from a disc and the other, BLR I, is probably optically-thin emission from a more spherically symmetric halo or atmosphere. The high Fe II/Hβ ratios seen in Narrow-Line Seyfert 1 galaxies (NLS1s) are not due to strong Fe II emission, as is commonly thought, but to unusually weak Balmer emission, probably caused by higher densities. NLS1s probably differ from non-NLS1s because of the higher density of gas near the black hole. This produces a higher accretion rate, a denser BLR, and a view of the central regions that is more face-on.
In Vivo Effects of Myeloablative Alkylator Therapy on Survival and Differentiation of MGMTP140K-Transduced Human G-CSF-Mobilized Peripheral Blood Cells

High-intensity alkylator-based chemotherapy is required to eradicate tumors expressing high levels of O6-methylguanine DNA methyltransferase (MGMT). This treatment, however, can lead to life-threatening myelosuppression. We investigated a gene therapy strategy to protect human granulocyte colony-stimulating factor-mobilized peripheral blood CD34+ cells (MPB) from a high-intensity alkylator-based regimen. We transduced MPB with an oncoretroviral vector that coexpresses MGMTP140K and the enhanced green fluorescent protein (EGFP) (n = 5 donors). At 4 weeks posttransplantation into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice, cohorts were not treated or were treated with low- or high-intensity alkylating chemotherapy. In the high-intensity-treated cohort, it was necessary to infuse NOD/SCID bone marrow (BM) to alleviate hematopoietic toxicity. At 8 weeks posttreatment, human CD45+ cells in the BM of mice treated with either regimen were EGFP+ and contained MGMT-specific DNA repair activity. In cohorts receiving low-intensity therapy, both primitive and mature hematopoietic cells were present in the BM. Although B-lymphoid and myeloid cells were resistant to in vivo drug treatment in cohorts that received high-intensity therapy, no human CD34+ cells or B-cell precursors were detected. These data suggest that improved strategies to optimize repair of DNA damage in primitive human hematopoietic cells are needed when using high-intensity anti-cancer therapy.
Nickel-catalyzed cyclizations of alkynyl enones and alkynyl enals

Substrates that possess an α,β-unsaturated carbonyl tethered to an alkyne have been utilized in a variety of nickel-catalyzed processes. Depending on ligand structure, reagent structure, reaction conditions, and workup conditions, several different monocyclic and bicyclic ring systems may be accessed from a common substrate. Evidence for a nickel met- allacycle as a common intermediate is provided.
The status of black-hole binary merger simulations with numerical relativity

The advent of long-term stability in numerical relativity has yielded a windfall of answers to long-standing questions regarding the dynamics of space-time, matter, and electromagnetic fields in the strong-field regime of black-hole binary mergers. In this review, we will briefly summarize the methodology currently applied to these problems, emphasizing the most recent advancements. We will discuss recent results of astrophysical relevance, and present some novel interpretation. Although we primarily present a review, we also present a simple analytical model for the time-dependent Poynting flux from two orbiting black holes immersed in a magnetic field, which compares favorably with recent numerical results. Finally, we will discuss recent advancements in our theoretical understanding of merger dynamics and gravitational waveforms that have resulted from interpreting the ever-growing body of numerical relativity results.
Dehn surgeries that yield fibred 3-manifolds

We study Dehn surgeries on null-homotopic knots that yield fibred 3-manifolds when an additional (but natural) homological restriction is imposed. The major tool used is Gabai’s theory of sutured manifold decomposition. Such surgeries are negative examples to a question of Michel Boileau. Another result we will prove is about surgeries which reduce the Thurston norm of a fibred manifold.
Transfer Function Tracking of a Linear Time-Varying System By Means of Auxiliary Simple Lag Networks

One of the most important problems facing a control engineer today is to find a simple and satisfactory method for determining the transfer function of an unknown time-varying control system. In this paper the transfer function is represented by a gain constant and ratio of two rational polynomials of s, where s is Laplace variable. The gain constant and the coefficients in the polynomials vary in an unknown fashion but rather slowly. A method is developed whereby as many independent signals are developed as the number of unknown coefficients. These signals are used to determine the unknown coefficients in a straightforward manner.
Z-Selective and Syndioselective Ring-Opening Metathesis Polymerization (ROMP) Initiated by Monoaryloxidepyrrolide (MAP) Catalysts

We report the Z-selective and syndioselective polymerization of 2,3-bis(trifluoromethyl)bicyclo[2.2.1]hepta-2,5-diene (NBDF6) and 3-methyl-3-phenylcyclopropene (MPCP) by monoaryloxide monopyrrolide imido alkylidene (MAP) catalysts of Mo. The mechanism of polymerization with syn-Mo(NAd)(CHCMe2Ph)(Pyr)(OHIPT) (1; Ad = 1-adamantyl, OHIPT = O-2,6-(2,4,6-i-Pr3C6H2)2C6H3) as the initiator is proposed to consist of addition of monomer to the syn initiator to yield a syn first insertion product and propagation via syn insertion products. In contrast, the mechanism of polymerization with syn-Mo(NAr)(CHCMe2Ph)(Pyr)(OTPP) (4; Ar = 2,6-i-Pr2C6H3, OTPP = 2,3,5,6-Ph4C6H) as the initiator at −78 °C consists of addition of monomer to the syn initiator to yield an anti first insertion product and propagation via anti insertion products. Polymerizations of NBDF6 and MPCP at room temperature initiated by 4 led to polymers without a regular structure. We propose that the syndiotacticity of cis polymers is the consequence of ...
Availability in the Sprite distributed file system

In the Sprite environment, tolerating faults means recovering from them quickly. Our position is that performance and availability are the desired features of the typical locally-distributed office/engineering environment, and that very fast server recovery is the most cost-effective way of providing such availability. Mechanisms used for reliability can be inappropriate in systems with the primary goal of performance, and some availability-oriented methods using replicated hardware or processes cost too much for these systems. In contrast, availability via fast recovery need not slow down a system, and our experience in Sprite shows that in some cases the same techniques that provide high performance also provide fast recovery. In our first attempt to reduce file server recovery times to less than 90 seconds, we take advantage of the distributed state already present in our file system, and a high-performance log-structured file system currently under implementation. As a long-term goal, we hope to reduce recovery to 10 seconds or less.
Chinese segmentation disambiguation

A technique of reasoning under uncertainty is studied in an attempt to solve disambiguation problems of Chinese segmentation. A knowledge-based inexact reasoning theory incorporating knowledge in morphology, syntax, semantics and pragmatics is presented.
Lodopyridone, a Structurally Unprecedented Alkaloid from a Marine Actinomycete

Chemical examination of the secondary metabolites of a marine Saccharomonospora sp., isolated from marine sediments collected at the mouth of the La Jolla Submarine Canyon, yielded the unprecedented alkaloid lodopyridone (1). The low proton-to-carbon ratio of 1 precluded structure elucidation by NMR spectroscopic methods, thus the structure was defined by X-ray crystallography. Lodopyridone is cytotoxic to HCT-116 human colon cancer cells with IC50 = 3.6 μM.
What's in a Name? Generics and the Persistence of the Pharmaceutical Brand in American Medicine

This paper explores the complex role that brand names have played in the maintenance of therapeutic standards within twentieth-century American medicine. What made a generic drug generic in the second half of the twentieth century—and by extension, what made a nonproprietary drug not proprietary in the first half—was dependent on changing drug branding practices and evolving standards of evidence attached to claims of therapeutic efficacy and safety. This article maps three eras of shifting oppositions between branded and unbranded pharmaceuticals. First, an era of “ethical marketing,” extending from before the Pure Food and Drug Act of 1906 into roughly the 1930s, which pitted nonproprietary or “ethical” pharmaceuticals against proprietary or patent medicines; second, an era of ascendant brand-name prescribing from the 1930s until roughly the 1960s, as manufacturers of innovative and patent-protected “specialty” drugs depicted generic production as a form of counterfeiting; and finally, an era of generic backlash from the 1960s onwards, which assumed the interchangeability of branded and generic drugs. This article uses clinical, popular, policy, and trade literatures to explore the enduring roles of brand-logic in the face of generic competition in the American drug market.
Disturbing the Dyson Conjecture (in a GOOD Way)

We present a case study in experimental yet rigorous mathematics by describing an algorithm, fully implemented in both Mathematica and Maple, that automatically conjectures, and then automatically proves, closed-form expressions extending Dyson's celebrated constant-term conjecture.
Differential operators, shifted parts, and hook lengths

We discuss Sakaguchi-type differential operators, their eigenvalues, and a generalization of Andrews–Goulden–Jackson formula. These will be applied to extract explicit formulae involving shifted partitions and hook lengths.