cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of vacuum exposure on stress and spectral shift of high reflective coatings

Coating stress and spectral shift are affected by changing from ambient to vacuum environments. This change can affect optical systems that are aligned in air and used in a vacuum or in a dry environment. Spectral shifts up to 3% and reflected wave-front changes up to 0.35 waves peak to valley are reported for conventional electron-beam deposition and ion-assisted deposition. Alternatively, ion-beam sputtered coatings have virtually no changes between different pressure environments.
Shape memory epoxy: a systematic study of their performance

Seven epoxy-amine polymers showing shape memory (SM) properties were synthesized. Tunable thermal and mechanical properties with glass transition temperatures ranging from 44 to 93 °C were obtained by varying the molecular structures. The epoxy showed excellent SM properties with shape fixity and shape recovery reaching completeness above about 5% strains. The instantaneous SM behavior was found to be independent of materials structure or properties; however, more stringent experimental conditions were found to be detrimental to SM properties for the networks with lower crosslink density and/or higher molecular flexibility/mobility. Indeed, the impact of the shape memory cycling conditions on the SM behavior was investigated. Specifically, the deformation load, the recovery heating rate, the number of SM cycles, and the holding time in the deformed or temporary shape were varied. The mechanical and SM properties of the materials were characterized using dynamic mechanical analysis in tensile mode.
Fragmentation of cosmic-string loops.

The fragmentation of cosmic string loops is discussed, and the results of a simulation of this process are presented. The simulation can evolve any of a large class of loops essentially exactly, including allowing fragments that collide to join together. Such reconnection enhances the production of small fragments, but not drastically. With or without reconnections, the fragmentation process produces a collection of nonself-intersecting loops whose typical length is on the order of the persistence length of the initial loop.
Numerical investigation of dynamic stall of an oscillating wing

The unsteady three-dimensional flowfield over an oscillating wing is investigated with the numerical solution of the compressible, time-dependent, Reynolds-averaged Navier-Stokes equations. Spatial discretization is performed with a third-order accurate, upwind-biased, vertex-based, finite volume scheme. An alternative direction implicit, iterative scheme is used for the time integration. The high Reynolds number turbulent flow behavior is modeled with a one-equation turbulence model. The effect of subiterations, time step and grid density on the accuracy of the computed solutions is investigated. It is found that scaling of the time step with the angular velocity of the motion produces accurate solutions at a reduced computational cost. The computational domain over an aspect ratio 5 wing with rounded tip and NACA-0015 airfoil sections is discretized with a single-block grid. The light stall flowfield over the wing oscillating in a subsonic freestream with a mean angle of attack of 11 deg and an amplitude of 4.2 deg is computed. The structure of the separated, unsteady flowfield is investigated and comparisons with available experimental data are performed.
Lower provider volume is associated with higher failure rates for endoscopic retrograde cholangiopancreatography.

BACKGROUND Among physicians who perform endoscopic retrograde cholangiopancreatography (ERCP), the relationship between procedure volume and outcome is unknown. OBJECTIVE Quantify the ERCP volume-outcome relationship by measuring provider-specific failure rates, hospitalization rates, and other quality measures. RESEARCH DESIGN Retrospective cohort. SUBJECTS A total of 16,968 ERCPs performed by 130 physicians between 2001 and 2011, identified in the Indiana Network for Patient Care. MEASURES Physicians were classified by their average annual Indiana Network for Patient Care volume and stratified into low (<25/y) and high (≥25/y). Outcomes included failed procedures, defined as repeat ERCP, percutaneous transhepatic cholangiography or surgical exploration of the bile duct≤7 days after the index procedure, hospitalization rates, and 30-day mortality. RESULTS Among 15,514 index ERCPs, there were 1163 (7.5%) failures; the failure rate was higher among low (9.5%) compared with high volume (5.7%) providers (P<0.001). A second ERCP within 7 days (a subgroup of failure rate) occurred more frequently when the original ERCP was performed by a low-volume (4.1%) versus a high-volume physician (2.3%, P=0.013). Patients were more frequently hospitalized within 24 hours when the ERCP was performed by a low-volume (28.3%) versus high-volume physician (14.8%, P=0.002). Mortality within 30 days was similar (low=1.9%, high=1.9%). Among low-volume physicians and after adjusting, the odds of having a failed procedure decreased 3.3% (95% confidence interval, 1.6%-5.0%, P<0.001) with each additional ERCP performed per year. CONCLUSIONS Lower provider volume is associated with higher failure rate for ERCP, and greater need for postprocedure hospitalization.
The Chemistry of Silylcyclopropanes

The synthesis and reactions of silylcyclopropanes are reviewed. From the preparative viewpoint, these strained systems can be obtained by the addition of silyl-substituted carbenes to olefins and of carbenes or carbenoids to vinylsilanes, by condensation of cyclopropyllithiums with chlorosilanes, by ring opening of silyl-substituted bicyclobutanes and by trimethylsilylmethylenesulfurane addition to α,β-unsaturated ketones. The susceptibility of this class of molecules to acid- and base-promoted ring openings, electrophilic substitution and thermal rearrangement is detailed. These latter topics and a summary of the use of silylcyclopropanes as cyclopropene precursors are presented in a manner which stresses the unique synthetic utility conveyed by the presence of the silicon atom.
Eccentric behavior of disk galaxies

A theory is developed for the dynamics of eccentric perturbations of a disk galaxy residing in a spherical dark matter halo and including a spherical bulge component. The disk is represented as a large number N of rings with shifted centers and with perturbed azimuthal matter distributions. Account is taken of the dynamics of the shift of the matter at the galaxy's center which may include a massive black hole. The gravitational interactions between the rings and between the rings and the center is fully accounted for, but the halo and bulge components are treated as passive gravitational field sources. Equations of motion and a Lagrangian are derived for the ring+center system, and these lead to total energy and total angular momentum constants of the motion. We first study the eccentric motion of a disk consisting of two rings of different radii but equal mass, Md/2. For small Md the two rings are stable, but for Md larger than a threshold value the rings are unstable with a dynamical timescale growth. For Md sufficiently above this threshold, the instability acts to decrease the angular momentum of the inner ring, while increasing that of the outer ring. The instability results from the merging positive and negative energy modes with increasing Md. Second, we analyze the eccentric motion of one ring interacting with a radially shifted central mass. In this case instability sets in above a threshold value of the central mass (for a fixed ring mass), and it acts to increase the angular momentum of the central mass (which therefore rotates in the direction of the disk matter), while decreasing the angular momentum of the ring. Third, we study the eccentric dynamics of a disk with an exponential surface density distribution represented by a large number of rings. The inner part of the disk is found to be strongly unstable. Angular momentum of the rings is transferred outward and to the central mass if present, and a trailing one-armed spiral wave is formed in the disk. Fourth, we analyze a disk with a modified exponential density distribution where the density of the inner part of the disk is reduced. In this case we find much slower, linear growth of the eccentric motion. A trailing one-armed spiral wave forms in the disk and becomes more tightly wrapped as time increases. The motion of the central mass if present is small compared with that of the disk.
Sources of aggregate labour productivity growth in Canada and the United States

Abstract. In this paper we propose a decomposition technique to examine the sources of industrial contribution to aggregate labour productivity growth. We show that in terms of pure labour productivity growth, the manufacturing and service sectors contributed equally to the aggregate Canada-U.S. labour productivity growth gap during the 1987–98 period. But, in terms of total industrial contributions, which also take into account the contributions from a change in relative size, the service sector was the largest contributor. We also find that high labour productivity growth industries did not attract resources from stagnant industries – a phenomenon consistent with Baumol's cost disease of stagnant industries. JEL Classification: O47, C43
A fuzzy model for unsupervised character classification

Abstract This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness, and speed of a character recognition system. The characters are first split into seven typographical categories. The classification scheme uses pattern matching to classify the characters in each category into a set of fuzzy prototypes based on a nonlinear weighted similarity function. The fuzzy unsupervised character classification, which is natural in the representation of prototypes for character matching, is developed and a weighted fuzzy similarity measure is explored. The characteristics of the fuzzy model are discussed and used in speeding up the classification process. After classification, the character recognition which is simply applied on a smaller set of the fuzzy prototypes, becomes much easier and less time-consuming.
Is the Cepheus E Outflow Driven by a Class 0 Protostar

New early release observations of the Cepheus E outflow and its embedded source, obtained with the Spitzer Space Telescope, are presented. We show that the driving source is detected in all four Infrared Array Camera (IRAC) bands, which suggests that traditional Class 0 classification, although essentially correct, needs to accommodate the new high-sensitivity infrared arrays and their ability to detect deeply embedded sources. Thus, we have determined a slope of the mid-infrared spectral energy distribution to be a = 5 ± 1 using only the IRAC fluxes. The IRAC and Multiband Imaging Photometer for Spitzer (MIPS) 24 and 70 μm new photometric points are consistent with a spectral energy distribution dominated by a cold, dense envelope surrounding the protostar. The Cep E outflow displays a very similar morphology in the near- and mid-infrared wavelengths and is detected at 24 μm. The interface between the dense molecular gas (where Cep E lies) and the less dense interstellar medium is well traced by the emission at 8 and 24 μm and is one of the most exotic features of the new IRAC and MIPS images. IRS observations of the north lobe of the flow confirm that most of the emission is due to the excitation of pure H2 rotational transitions arising from a relatively cold (Tex ~ 700 K) and dense (6.4 × 104 cm-3) molecular gas.
Bowel-associated dermatosis-arthritis syndrome: Bowel bypass syndrome without bowel bypass

The bowel bypass syndrome is a well-recognized complication in patients who have had jejunoileal bypass for morbid obesity. It consists of an influenzalike illness with increased temperature, chills, polyarthralgia, myalgia, and inflammatory papules and pustules that are 2 to 4 mm in diameter and that usually appear on the extremities and the upper part of the trunk. A patient is reported who had an identical bowel-associated dermatosis-arthritis syndrome but who had not undergone a jejunoileal bypass operation. Seven previously reported similar cases are reviewed.
A particle-number-conserving solution to the generalized pairing problem

Abstract An exact, number-conserving solution to the generalized, orbit-dependent pairing problem is derived by introducing an infinite-dimensional algebra. A method for obtaining eigenvalues and eigenvectors of the corresponding Hamiltonian is also given. The relevance of the orbit-dependent pairing solution is demonstrated by comparing predictions of the model with shell-model calculations.
Microprisms for in vivo multiphoton microscopy of mouse cortex

Microprisms inserted into the cortex of mouse enable in vivo multiphoton microscopy, rotating the field-of-view from parallel to perpendicular to the surface of cortex and allowing imaging of the full cortical thickness.
Correspondence theorems for hierarchies of equations of pseudo-spherical type

Hierarchies of evolution equations of pseudo-spherical type are introduced, thereby generalizing the notion of a single equation describing pseudo-spherical surfaces due to S.S. Chern and K. Tenenblat, and providing a connection between differential geometry and the study of hierarchies of equations which are the integrability condition of sl(2,R)-valued linear problems. As an application, it is shown that there exist local correspondences between any two (suitably generic) solutions of arbitrary hierarchies of equations of pseudo-spherical type.
A probability-driven multilayer framework for scheduling intermittent renewable energy

A probability-driven, multilayer framework is proposed in this paper for ISOs to schedule intermittent wind power and other renewables. The basic idea is to view the intermittent renewable energy as a product with lower quality (i.e., the probability of energy availability in real time) than dispatchable power plants, such as thermal or hydro, from the operators' viewpoint. “Layers” considering the probability of delivery are proposed, such that various loads (critical load or non-essential controllable load) may participate in different layers in the energy market. A layer with a lower expected probability of energy availability is generally expected to have a lower price. This is similar to having different prices for commodities of different qualities. A methodology is proposed to gradually merge multilayers in the day-ahead market to a single deterministic layer in real-time. The merge is needed because the market must be deterministic in real time, whether sources are available or not. This is also reasonable because participants are more certain about the available power output the closer to real time. Further, the proposed scheduling framework is extended to consider the transmission constraints with a case study based on a modified version of the PJM 5-bus system.
Photodegradation of coumarin laser dyes: an unexpected singlet self-quenching mechanism

Abstract The photolysis of a series of aminocoumarin laser dyes, including 7-diethylamino-4-methylcoumarin (1), has been investigated. Dealkylation of groups at the 7-dialkylamino functionality, reduction of the lactone moiety and overall photodecomposition of the dyes have been observed. Concentration quenching of dye fluorescence is important at concentrations above 0.01 M. The concentration dependence of photoreduction is shown to be consistent with a singlet self-quenching mechanism. Dye photodegradation is not quenched on addition of trans-stilbene, although the latter is an effective quencher of the triplet of 1. Intersystem crossing yields for the coumarin dyes are very low. A mechanism for dye photodegradation is proposed involving singlet self-quenching and net hydrogen atom transfer between dye molecules, followed by disproportionation and coupling of radicals.
Quantum key distribution using three basis states

This note presents a method of public key distribution using quantum communication of n photons that simultaneously provides a high probability that the bits have not been tampered. It is a variant of the quantum method of Bennett and Brassard (BB84) where the transmission states have been decreased from 4 to 3 and the detector states have been increased from 2 to 3. Under certain assumptions regarding method of attack, it provides superior performance (in terms of the number of usable key bits) for n<18m, where m is the number of key bits used to verify the integrity of the process in the BB84-protocol.
Evaluation criteria for human-automation performance metrics

Previous research has identified broad metric classes for human-automation performance to facilitate metric selection, as well as understanding and comparison of research results. However, there is still lack of an objective method for selecting the most efficient set of metrics. This research identifies and presents a list of evaluation criteria that can help determine the quality of a metric in terms of experimental constraints, comprehensive understanding, construct validity, statistical efficiency, and measurement technique efficiency. Future research will build on these evaluation criteria and existing generic metric classes to develop a cost-benefit analysis approach that can be used for metric selection.
Unexpected impact of D waves in low-energy neutral pion photoproduction from the proton and the extraction of multipoles

Contributions of D waves to physical observables for neutral pion photoproduction from the proton in the near-threshold region are studied and means to isolate them are proposed. Various approaches to describe the multipoles are employed--a phenomenological one, a unitary one, and heavy baryon chiral perturbation theory. The results of these approaches are compared and found to yield essentially the same answers. D waves are seen to enter together with S waves in a way that any means which attempt to obtain the E{sub 0+} multipole accurately must rely on knowledge of D waves and that consequently the latter cannot be dismissed in analyses of low-energy pion photoproduction. It is shown that D waves have a significant impact on double-polarization observables that can be measured. This importance of D waves is due to the soft nature of the S wave and is a direct consequence of chiral symmetry and the Nambu-Goldstone nature of the pion. F-wave contributions are shown to be negligible in the near-threshold region.
Some aspects of brane inflation

Abstract The inflaton potential in four-dimensional theory is rather arbitrary, and fine-tuning is required generically. By contrast, inflation in the brane world scenario has the interesting feature that the inflaton potential is motivated from higher-dimensional gravity, or more generally, from bulk modes or string theory. We emphasize this feature with examples. We also consider the impact on the spectrum of density perturbation from a velocity-dependent potential between branes in the brane inflationary scenario. It is likely that such a potential can have an observable effect on the ratio of tensor to scalar perturbations.
The Federal Reserve’s operating procedure, nonborrowed reserves, borrowed reserves and the liquidity effect

Abstract Recently, a number of researchers (Christiano and Eichenbaum, 1992; Christiano et al., 1996a,b, 1997; Evans and Marshall, 1998; Strongin, 1995; Pagan and Robertson, 1995; Brunner, 1994) claim to have found evidence of a statistically significant liquidity effect in a recursive structural VAR using nonborrowed reserves (NBR). It is claimed that innovations to NBR reflect the exogenous policy actions of the Fed. This paper argues that the opposite is true. Specifically, I show that the Fed has an incentive to offset bank-initiated discount window borrowing when it implements the Federal Open Market Committee’s policy directive, and that it has done so since the late 1950s. This practice has created a negative contemporaneous covariance between NBR and the funds rate that has been incorrectly attributed to the liquidity effect. By showing that these models capture the endogenous response of the Fed to bank borrowing on NBR, rather than the effect of exogenous policy actions on the funds rate, this paper also resolves the puzzle of the vanishing liquidity effect noted by Pagan and Robertson (1995) and Christiano (1995) .
Scaling and Renormalization in Fault-Tolerant Quantum Computers

This work is concerned with phrasing the concepts of fault-tolerant quantum computation within the framework of disordered systems, Bernoulli site percolation in particular. We show how the so-called “threshold theorems” on the possibility of fault-tolerant quantum computation with constant error rate can be cast as a renormalization (coarse-graining) of the site percolation process describing the occurrence of errors during computation. We also use percolation techniques to derive a trade-off between the complexity overhead of the fault-tolerant circuit and the threshold error rate. PACS: 03.67.Pp; 03.67.Lx
C II Radiative Cooling of the Diffuse Gas in the Milky Way

The heating and cooling of the interstellar medium (ISM) allow the gas in the ISM to coexist at very different temperatures in thermal pressure equilibrium. The rate at which the gas cools or heats is therefore a fundamental ingredient for any theory of the ISM. The heating cannot be directly determined, but the cooling can be inferred from observations of ·C *, which is an important coolant in different environments. The amount of cooling can be measured through either the intensity of the 157.7 μm [C II] emission line or the C * absorption lines at 1037.018 and 1335.708 A, observable with the Far Ultraviolet Spectroscopic Explorer and the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, respectively. We present the results of a survey of these far-UV absorption lines in 43 objects situated at b 30°. Measured column densities of C *, S II, P II, and Fe II are combined with H I 21 cm emission measurements to derive the cooling rates (per H atom using H I and per nucleon using S II) and to analyze the ionization structure, depletion, and metallicity content of the low-, intermediate-, and high-velocity clouds (LVCs, IVCs, and HVCs) along the different sight lines. Based on the depletion and the ionization structure, the LVCs, IVCs, and HVCs consist mostly of warm neutral and ionized clouds. For the LVCs, the mean cooling rate in ergs s-1 per H atom is -25.70 dex (1 σ dispersion). With a smaller sample and a bias toward high H I column density, the cooling rate per nucleon is similar. The corresponding total Galactic C II luminosity in the 157.7 μm emission line is L ~ 2.6 × 107 L☉. Combining N(C *) with the intensity of Hα emission, we derive that ~50% of the C * radiative cooling comes from the warm ionized medium (WIM). The large dispersion in the cooling rates is certainly due to a combination of differences in the ionization fraction, in the dust-to-gas fraction, and physical conditions between sight lines. For the IVC Intermediate-Velocity (IV) Arch at z ~ 1 kpc we find that on average the cooling is a factor of 2 lower than in the LVCs that probe gas at lower z. For an HVC (complex C, at z > 6 kpc) we find the much lower rate of -26.99 dex, similar to the rates observed in a sample of damped Lyα absorber systems (DLAs). The fact that in the Milky Way a substantial fraction of the C II cooling comes from the WIM implies that this is probably also true in the DLAs. We also derive the electron density, assuming a typical temperature of the warm gas of 6000 K: for the LVCs, ne = 0.08 ± 0.04 cm-3, and for the IV Arch, ne = 0.03 ± 0.01 cm-3 (1 σ dispersion). Finally, we measured the column densities N(S II) and N(P II) in many sight lines and confirm that sulphur appears undepleted in the ISM. Phosphorus becomes progressively more deficient when log N(H ) > 19.7 dex, which can mean that either P becomes more depleted into dust as more neutral gas is present or P is always depleted by about -0.3 dex, but the higher value of P II at lower H I column density indicates the need for an ionization correction.
The ruled vertex and D-E degenerations

We compute all genus topological amplitudes on configurations of ruled surfaces obtained by resolving lines of D-E singularities in compact Calabi-Yau threefolds. We find that our results are in agreement with genus zero mirror symmetry calculations, which is further evidence for the validity of the ruled vertex formalism for degenerate torus actions.
Biofuel’s carbon balance: doubts, certainties and implications

Liquid fuels will remain valued energy carriers well into any upcoming period when CO2 reductions are sought. Biofuels are the presumed replacement for the petroleum-based transportation fuels that dominate liquid fuel use. Lifecycle analysis embeds a closed-loop model of biofuel-related carbon flows, making net CO2 uptake an assumption to be refuted. However, evaluating net CO2 uptake through dynamic industrial and agriforestry supply chains at real-world commercial scales is extremely difficult. All such estimates carry a great deal of doubt and cannot be verified empirically. A different perspective follows by anchoring analysis inthecertaintythatend-useCO2emissionsfrombiofuelsareessentiallythesameasthoseofthe petroleum fuels they replace. A first-order model of the globally coupled bio- and fossil-fuel system reveals conditions for biofuel use to provide an atmospheric benefit. No benefit occurs in theenergysectorswherebiofuelsareused,butrather must be foundelsewhereinlocationsof carbonabsorptionorretention.Theimplicationisthatclimatemitigationeffortsshouldfocuson such locations and include any mechanisms through which net uptake (an enhanced sink or verifiable offset) can be achieved by biological, chemical, geological or other means. Although biofuels can play a mitigation role when certain conditions are met, deemphasizing biofuel production in favor of terrestrial carbon management may offer more immediate and effective ways to counterbalance the CO2 emitted when using carbon-based liquid fuels of any origin. Climate policies for transportation fuels should be reconsidered accordingly.
Fast-Collapsing Theories

Reinhardt's conjecture, a formalization of the statement that a truthful knowing machine can know its own truthfulness and mechanicalness, was proved by Carlson using sophisticated structural results about the ordinals and transfinite induction just beyond the first epsilon number. We prove a weaker version of the conjecture, by elementary methods and transfinite induction up to a smaller ordinal.
Micromotion-Induced Limit to Atom-Ion Sympathetic Cooling in Paul Traps

We present, and derive analytic expressions for, a fundamental limit to the sympathetic cooling of ions in radio-frequency traps using cold atoms. The limit arises from the work done by the trap electric field during a long-range ion-atom collision and applies even to cooling by a zero-temperature atomic gas in a perfectly compensated trap. We conclude that in current experimental implementations, this collisional heating prevents access to the regimes of single-partial-wave atom-ion interaction or quantized ion motion. We determine conditions on the atom-ion mass ratio and on the trap parameters for reaching the s-wave collision regime and the trap ground state.
Alternating Markov chains for distribution estimation in the presence of errors

We consider a class of small-sample distribution estimators over noisy channels. Our estimators are designed for repetition channels, and rely on properties of the runs of the observed sequences. These runs are modeled via special types of Markov chains, termed “alternating Markov chains”. We show that alternating chains have redundancy that scales sub-linearly with the lengths of the sequences, and describe how to use a distribution estimator for alternating chains for the purpose of distribution estimation over repetition channels.
The Schizophrenic Spectrum of LSR 1610−0040: A Peculiar M Dwarf/Subdwarf

We present a moderate-resolution (R ≡ λ/Δλ ≈ 2000), 0.8-4.1 μm spectrum of LSR 1610-0040, a high proper motion star classified as an early-type L subdwarf by Lepine and collaborators based on its red-optical spectrum. The near-infrared spectrum of LSR 1610-0040 does not fit into the (tentative) M/L subdwarf sequence but rather exhibits a mix of characteristics found in the spectra of both M dwarfs and M subdwarfs. In particular, the near-infrared spectrum exhibits an Na I doublet and CO overtone band heads in the K band and Al I and K I lines and an FeH band head in the H band, all of which have strengths more typical of field M dwarfs. Furthermore, the spectrum of Gl 406 (M6 V) provides a reasonably good match to the 0.6-4.1 μm spectral energy distribution of LSR 1610-0040. Nevertheless, the near-infrared spectrum of LSR 1610-0040 also exhibits features common to the spectra of M subdwarfs, including a strong Ti I multiplet centered at ~0.97 μm, a weak VO band at ~1.06 μm, and possible collision-induced H2 absorption in the H and K bands. We discuss a number of possible explanations for the appearance of the red-optical and near-infrared spectra of LSR 1610-0040. Although we are unable to definitively classify LSR 1610-0040, the preponderance of evidence suggests that it is a mildly metal-poor M dwarf. Finally, we tentatively identify a new band of TiO at ~0.93 μm in the spectra of M dwarfs.
Abundances of Baade's Window Giants from Keck HIRES Spectra. I. Stellar Parameters and [Fe/H] Values

We present the first results of a new abundance survey of the Milky Way bulge based on Keck HIRES spectra of 27 K giants in the Baade's Window (l = 1°, b = -4°) field. The spectral data used in this study are of much higher resolution and signal-to-noise ratio than previous optical studies of Galactic bulge stars. The [Fe/H] values of our stars, which range between -1.29 and +0.51, were used to recalibrate large low-resolution surveys of bulge stars. Our best value for the mean [Fe/H] of the bulge is -0.10 ± 0.04. This mean value is similar to the mean metallicity of the local disk and indicates that there cannot be a strong metallicity gradient inside the solar circle. The metallicity distribution of stars confirms that the bulge does not suffer from the so-called G dwarf problem. This paper also details the new abundance techniques necessary to analyze very metal-rich K giants, including a new Fe line list and regions of low blanketing for continuum identification.
The endomorphism rings of jacobians of cyclic covers of the projective line

Suppose that $K$ is a field of characteristic zero, $K_a$ is its algebraic closure, and that $f(x) \in K[x]$ is an irreducible polynomial of degree $n \ge 5$ , whose Galois group coincides either with the full symmetric group $\Sn$ or with the alternating group $\An$ . Let $p$ be an odd prime, $\Z[\zeta_p]$ the ring of integers in the $p$ th cyclotomic field $\Q(\zeta_p)$ . Suppose that $C$ is the smooth projective model of the affine curve $y^p\,{=}\,f(x)$ and $J(C)$ is the jacobian of $C$ . We prove that the ring $\End(J(C))$ of $K_a$ -endomorphisms of $J(C)$ is canonically isomorphic to $\Z[\zeta_p]$
Influence of a Shroud on Swirler Flow Fields

The flow fields for swirlers with and without a shroud were measured using a two-component Laser Doppler Velocimeter (LDV) system. The primary goal of this study is to investigate the effect of shrouds on swirler flow fields, in order to provide useful design information for the manufacture of gas turbine fuel nozzles, and to supply benchmark data for comparison with numerical predictions. As a result of the measurements, the radial distributions of three mean velocity components, turbulence intensity, and shear stresses were obtained at five locations (x/d = 0.1, 1, 2, 4 and 8) along the axis of the swirlers. The LDV system was operated in the 20° off-axis forward scatter mode with beam expanders and Bragg cell frequency shifting on both components. The flow was seeded by 1 μm mean diameter atomized particles of glycerol and water (50/50) mixture. Comparison of flow with and without the shroud showed that the jet diameter was much smaller, and the flow deceleration in the downstream direction was faster, due to the influence of the shroud, at the same supply pressure (750 mm H2O). As a result of the significant reduction in the swirl number due to the addition of the shroud, the recirculation zone disappeared. In addition to its influence on recirculation, the shroud caused a radially inward shift of the maximum mean and turbulence parameters at all axial locations. The anisotropy of turbulence increased as compared to the values for the swirler without the shroud.Copyright © 1990 by ASME
An efficient 1,2-chelation-controlled reduction of protected hydroxy ketones via Red-Al.

In this paper, we have demonstrated that Red-Al is an efficient chelation-controlled reducing reagent for acyclic acetal (i.e., MOM, MEM, SEM, and BOM) protected α-hydroxy ketones. Typically, diastereomeric ratios (dr) ranged from 5 to 20:1 for the 1,2-anti-diols in good to excellent yields.
Scaling Phenomena in Fatigue and Fracture

The general classification of scaling laws will be presented and the basic concepts of modern similarity analysis - intermediate asymptotics, complete and incomplete similarity - will be introduced and discussed. The examples of scaling laws corresponding to complete similarity will be given. The Paris scaling law in fatigue will be discussed as an instructive example of incomplete similarity. It will be emphasized that in the Paris law the powers are not the material constants. Therefore, the evaluation of the life-time of structures using the data obtained from standard fatigue tests requires some precautions.
Photoacoustic probes for nondestructive testing and biomedical applications

Fiber-optic photoacoustic sources for nondestructive testing and biomedical applications are described. The photoacoustic sources consist of a pulsed laser, a fiber-optic cable, and a generation head. The generation head is a miniature hermetically sealed chamber, which can be embedded into solid structures or immersed in liquid media. The face of the chamber acts as a target for laser irradiation. Bulk ultrasonic waves generated inside of the target are transmitted into the medium. The proposed systems offer wide ultrasonic range (0.5-15 MHz), easy control over directivity of the ultrasonic beam, high efficiency of generation, and the ability to operate in a harsh environment. Sources with different radiation patterns with respect to the optical axis of the fiber, such as normal, sideways, as well as focused, have been devised. We present a proof-of-concept experiment using these sources in combination with fiber-optic ultrasonic receivers.
A Market-Forces Policy for the New Farm Economy?

This paper first discusses the changes that are bringing about the New Farm Economy. A wave of consolidation has shifted agricultural production to larger, lower cost producers in almost all sectors of agriculture. At the same time, supply chains represent a new form of ownership and control that is replacing commodity markets as the preferred way to market farm output. Both consolidation and the development of supply chains offer the possibility of producing a greater variety of safer, cheaper food. The paper argues that farm policy, crafted for the agriculture of the 1930s, is no longer necessary to raise or stabilize farm incomes, and is largely ineffective anyway. Moreover, farm policy impedes the market forces driving innovation and efficiency in the farm economy. Letting market forces guide the evolution of the farm economy, unfettered by outdated government programs and unnecessary farm subsidies, is the best way to harness the benefits of the New Farm Economy. Getting rid of government subsidies and control will lead to dramatically fewer farmers in agriculture; a policy to deal explicitly with those who will leave agriculture is needed. A transition policy is described that focuses on helping reduce the number of farmers by offering a buyout to farm producers which subsidizes their exit from farming and prevents reentry.
Deficiency of ADAMTS13 and thrombotic thrombocytopenic purpura.

Bianchi et al[1][1] report that a severe deficiency of the von Willebrand factor (VWF)–cleaving protease ADAMTS13 is specific for thrombotic thrombocytopenic purpura (TTP). This is in agreement with the results of our studies, demonstrating that a severe deficiency of ADAMTS13 is detected only in
Homology of Littlewood complexes

Let \(V\) be a symplectic vector space of dimension \(2n\). Given a partition \(\lambda \) with at most \(n\) parts, there is an associated irreducible representation \(\mathbf{{S}}_{[\lambda ]}(V)\) of \(\mathbf{{Sp}}(V)\). This representation admits a resolution by a natural complex \(L^{\lambda }_{\bullet }\), which we call the Littlewood complex, whose terms are restrictions of representations of \(\mathbf{{GL}}(V)\). When \(\lambda \) has more than \(n\) parts, the representation \(\mathbf{{S}}_{[\lambda ]}(V)\) is not defined, but the Littlewood complex \(L^{\lambda }_{\bullet }\) still makes sense. The purpose of this paper is to compute its homology. We find that either \(L^{\lambda }_{\bullet }\) is acyclic or it has a unique nonzero homology group, which forms an irreducible representation of \(\mathbf{{Sp}}(V)\). The nonzero homology group, if it exists, can be computed by a rule reminiscent of that occurring in the Borel–Weil–Bott theorem. This result can be interpreted as the computation of the “derived specialization” of irreducible representations of \(\mathbf{{Sp}}(\infty )\) and as such categorifies earlier results of Koike–Terada on universal character rings. We prove analogous results for orthogonal and general linear groups. Along the way, we will see two topics from commutative algebra: the minimal free resolutions of determinantal ideals and Koszul homology.
The Death Effect of Severe Climate Variability

Abstract Using data for all 2,454 municipalities of Mexico for the period 1980-2010, this paper analyzes the relationship between exposure to extreme temperatures and mortality rates. I find that severe heat increases mortality, while the health effect of severe cold is generally trivial. I show that exchanging one day with a temperature of 16-18 °C for one day with temperatures higher than 30 °C increases the crude mortality rate by 0.15 percentage points, a result robust to several model specifications. It is also found that the extreme heat effect on death is significantly more acute in rural regions, leading to increases of up to 0.2 percentage points vis-a-vis a 0.07-point increase in urban areas.
FINITE ELEMENT ANALYSIS OF LOW VELOCITY IMPACT ON COMPOSITE SANDWICH PLATES

Abstract The response of composite sandwich plates to low-velocity impact is predicted by a displacement-based, plate bending, finite element algorithm. Fifth order Hermitian interpolation allows three-dimensional equilibrium integration for transverse stress calculations to be carried out symbolically on the interpolation functions so that transverse stresses within the elements are expressed directly in terms of nodal quantities. Nomex honeycomb sandwich core is modeled using an elastic–plastic foundation and contact loading is simulated by Hertzian pressure distribution for which the contact radius is determined iteratively. Damage prediction by failure criteria and damage progression via stiffness reduction are employed. Comparison to experimental low-velocity impact and static indentation data shows the ability to model some of the important features of static indentation of composite sandwich structures. In particular, the slope of the load displacement curve (stiffness), including contact, before damage is well represented. Core failure load is predicted by the analysis within 10% of the experimental value.
Scale anomalies imply violation of the averaged null energy condition

Abstract It is important to know whether or not quantum field theory on a fixed but curved background spacetime satisfies the so-called “averaged null energy condition” (ANEC). This result has a bearing on various important issues in semiclassical quantum gravity; such as the singularity theorems, the topological censorship theorem, and the positive mass theorem. A comment by Wald and Yurtsever indicates that the ANEC is often violated in curved spacetimes. In this letter I explore this issue in more detail, and succeed in characterizing a broad class of spacetimes in which the ANEC is guaranteed to be violated. I shall show that, modulo appropriate technical caveats, the occurrence of a particular quantum field theoretic anomaly — the scale anomaly — implies generic violations of the ANEC. Implications of this result are then briefly discussed.
On the application of GMRES to oscillatory singular integral equations

We present a new method for the numerical solution of singular integral equations on the real axis. The method’s value stems from a new formula for the Cauchy integral of a rational function with an oscillatory exponential factor. The inner product of such functions is also computed explicitly. With these tools in hand, the GMRES algorithm is applied to both non-oscillatory and oscillatory singular integral equations. In specific cases, ideas from Fredholm theory and Riemann–Hilbert problems are used to motivate preconditioners for these singular integral equations. A significant acceleration in convergence is realized for these examples. This presents a useful link between the theory of singular integral equations and the numerical analysis of such equations. Furthermore, this method presents a first step towards a solver for the inverse scattering transform that does not require the deformation of a Riemann–Hilbert problem.
Cabling and transverse simplicity

We study Legendrian knots in a cabled knot type. Specifically, given a topological knot type /C, we analyze the Legendrian knots in knot types ob tained from K by cabling, in terms of Legendrian knots in the knot type K. As a corollary of this analysis, we show that the (2,3)-cable of the (2,3)-torus knot is not transversely simple and moreover classify the transverse knots in this knot type. This is the first classification of transverse knots in a non transversely-simple knot type. We also classify Legendrian knots in this knot type and exhibit the first example of a Legendrian knot that does not destabi lize, yet its Thurston-Bennequin invariant is not maximal among Legendrian representatives in its knot type. In this paper we continue the investigation of Legendrian knots in tight contact 3-manifolds using 3-dimensional contact-topological methods. In [EH1], the authors introduced a general framework for analyzing Legendrian knots in tight contact 3-manifolds. There we streamlined the proof of the classification of Legendrian unknots, originally proved by Eliashberg-Eraser in [EF], and gave a complete classification of Legendrian torus knots and figure eight knots. In [EH2], we gave the first structure theorem for Legendrian knots, namely the reduction of the analysis of connected sums of Legendrian knots to that of the prime summands. This yielded a plethora of non-Legendrian-simple knot types. (A topological knot type is Legendrian simple if Legendrian knots in this knot type are determined by their Thurston-Bennequin invariant and rotation number.) Moreover, we exhibited pairs of Legendrian knots in the same topological knot type with the same Thurston-Bennequin and rotation numbers, which required arbitrarily many stabilizations before they became Legendrian isotopic (see [EH2]).
Teaching Immigration: Informing and Elevating the Debate

Based on the insights gained through my own teaching and that of others who participated in a roundtable discussion on the topic at the 4th Annual Conference on Immigration to the Southeast: Policy Analysis, Conflict Management (Kennesaw State University, October 2012), this essay uses current research about pedagogical best practices to argue that we should teach courses about immigration that are problem-based and interdisciplinary and include some combination of civic engagement, service learning, and faculty-student research. These practices are demonstrated to improve students’ skills, knowledge, and understanding, as well as their desire to be civically engaged.
Catalytic scaffolding ligands: an efficient strategy for directing reactions.

The design and application of a scaffolding ligand that promotes branch and diastereoselective hydroformylation of terminal olefins as well as the regio- and diastereoselective hydroformylation of disubstituted olefins is reported. It is shown that the ligand covalently and reversibly bonds to the substrate, allowing for directed hydroformylation. As the substrate ligand interaction is dynamic, hydroformylations are catalytic in ligand and do not require any additional synthetic steps to add or remove the directing group. Using a catalytic quantity of a scaffolding ligand (20−25 mol %), excellent regioselectivity for disubstituted olefins (up to 98:2) and high branch selectivity (up to 88:12) for terminal olefins were obtained.
Quantum-dot devices and Quantum-dot Cellular Automata

Abstract We discuss novel nanoelectronic architecture paradigms based on cells composed of coupled quantum dots. Boolean logic functions may be implemented in specific arrays of cells representing binary information, the so-called Quantum-Dot Cellular Automata (QCA). Cells may also be viewed as carrying analog information, and we outline a network-theoretic description of such Quantum-Dot Nonlinear Networks (Q-CNN). In addition, we discuss possible realizations of these structures in a variety of semiconductor systems (including GaAs/AlGaAs, Si/SiGe, and Si SiO 2 ), rings of metallic tunnel-junctions, and candidates for molecular implementations.
Organizational structure and the multinational strategy

Organizations that have a single or a few related product lines and a high degree of vertical integration tend to be capital intensive, and to be organized in a centralized, functionally-departmentalized structure. Organizations that have a diversified product line tend to have a decentralized, divisional structure. This paper indicates that the first type tends to concentrate on domestic markets, while the second type accounts for most of U. S. direct investment abroad. Expansion abroad requires diversification, reorganization, and the training of general international managers. The evidence suggests that the organizations that have been most successful in meeting this new challenge have been those that had previously acquired the ability to develop general managers capable of controlling and guiding a heterogeneous, diverse enterprise. Lawrence E. Fouraker is a professor of business administration and John M. Stopford is a research associate at the Harvard Graduate School of Business Administration.
Structural Properties of Superplastically Formed, Diffusion-Bonded Orthogonally Corrugated Core Sandwich Plates

This paper describes a new superplastically formed/diffusion-bonded (SPF/DB) orthogonally corrugated sandwich structure, and presents formulae and the associated plots for evaluating the effective elastic constants for the core of this new sandwich structure. Comparison of structural properties of this new sandwich structure with the conventional honeycomb core sandwich structure was made under the condition of equal sandwich density. It was found that the SPF/DB orthogonally corrugated sandwich core has higher transverse shear stiffness than the conventional honeycomb sandwich core. However, the former has lower stiffness in the sandwich core thickness direction than the latter.