cssi/SciSciGPT-SciSciNet huggingface dataset:
FEEDBACK IN LUMINOUS OBSCURED QUASARS

We use spatially resolved long-slit spectroscopy from Magellan to investigate the extent, kinematics, and ionization structure in the narrow-line regions of 15 luminous, obscured quasars with z < 0.5. Increasing the dynamic range in luminosity by an order of magnitude, as well as improving the depth of existing observations by a similar factor, we revisit relations between narrow-line region size and the luminosity and linewidth of the narrow emission lines. We find a slope of 0.22 {+-} 0.04 for the power-law relationship between size and luminosity, suggesting that the nebulae are limited by availability of gas to ionize at these luminosities. In fact, we find that the active galactic nucleus is effectively ionizing the interstellar medium over the full extent of the host galaxy. Broad ({approx}300-1000 km s{sup -1}) linewidths across the galaxies reveal that the gas is kinematically disturbed. Furthermore, the rotation curves and velocity dispersions of the ionized gas remain constant out to large distances, in striking contrast to normal and starburst galaxies. We argue that the gas in the entire host galaxy is significantly disturbed by the central active galactic nucleus. While only {approx}10{sup 7}-10{sup 8} M{sub sun} worth of gas are directly observed to be leavingmore » the host galaxies at or above their escape velocities, these estimates are likely lower limits because of the biases in both mass and outflow velocity measurements and may in fact be in accord with expectations of recent feedback models. Additionally, we report the discovery of two dual obscured quasars, one of which is blowing a large-scale ({approx}10 kpc) bubble of ionized gas into the intergalactic medium.« less
Stable Principal Component Pursuit

In this paper, we study the problem of recovering a low-rank matrix (the principal components) from a high-dimensional data matrix despite both small entry-wise noise and gross sparse errors. Recently, it has been shown that a convex program, named Principal Component Pursuit (PCP), can recover the low-rank matrix when the data matrix is corrupted by gross sparse errors. We further prove that the solution to a related convex program (a relaxed PCP) gives an estimate of the low-rank matrix that is simultaneously stable to small entry-wise noise and robust to gross sparse errors. More precisely, our result shows that the proposed convex program recovers the low-rank matrix even though a positive fraction of its entries are arbitrarily corrupted, with an error bound proportional to the noise level. We present simulation results to support our result and demonstrate that the new convex program accurately recovers the principal components (the low-rank matrix) under quite broad conditions. To our knowledge, this is the first result that shows the classical Principal Component Analysis (PCA), optimal for small i.i.d. noise, can be made robust to gross sparse errors; or the first that shows the newly proposed PCP can be made stable to small entry-wise perturbations.
Optimal highway design and user welfare under value pricing

Abstract This paper investigates the optimal design of highways operated under a form of congestion pricing called value pricing. Value pricing involves dividing a highway into free and priced lanes so that in equilibrium the highway effectively operates at two levels of service, with those users placing a higher value on travel time savings selecting the faster, priced route. A tractable analytical framework is developed which allows analysis of equilibrium and welfare on value priced highways when users vary in their value of time. The model is used to characterize optimal toll and capacity policies, as well as investigate the fiscal implications of value pricing. The analysis concludes with results on how welfare changes induced by value pricing are distributed over the population of users when the government finances any funding shortfall through a non-discriminatory taxing mechanism. A realistic numeric example is used to illustrate how the model can be applied to evaluation of actual and proposed value pricing implementations.
The use of passwords for controlling access to remote computer systems and services

The widespread use of remote computer resources has made the problem of personal authentication most urgent. This paper examines the use of passwords for controlled access to these resources. Password techniques, ways of protecting passwords, and attendant cost considerations are discussed. Similarities between passwords and data encryption keys are noted and general recommendations for the use of passwords are presented.
Direct Numerical Simulation of Three-Dimensional Flow and Augmented Heat Transfer in a Grooved Channel

Direct numerical simulations of three-dimensional flow and augmented convective heat transfer in a transversely grooved channel are presented for the Reynolds number range 140 < Re < 2000. These calculations employ the spectral element technique. Multiple flow transitions are documented as the Reynolds number increases, from steady two-dimensional flow through broad-banded unsteady three-dimensional mixing. Three-dimensional simulations correctly predict the Reynolds-number-independent friction factor behavior of this flow and quantify its heat transfer to within 16 percent of measured values. Two-dimensional simulations, however, incorrectly predict laminar-like friction factor and heat transfer behaviors
Postsecondary education as triage: Returns to academic and technical programs

Abstract This paper examines the labor market outcomes of individuals with various types of postsecondary educational experiences. In particular, it examines differences between students who have pursued technical education programs from those who have pursued academic programs and from those individuals who have not pursued any type of postsecondary education. Empirical evidence is presented concerning the relationship between economic outcomes and grades earned and the degree to which the labor market rewards credentials. Wage and earnings models yield different structural parameter estimates when based on the three different populations. The differences are most dramatic for high school background effects and for postsecondary characteristics. The empirical results from the technique used to correct for self-selection suggest that individuals' choices into the three postsecondary tracks do not reflect positive self-selection into all three tracks.
Mixing time of the card-cyclic-to-random shuffle

The card-cyclic-to-random shuffle on $n$ cards is defined as follows: at time $t$ remove the card with label $t$ mod $n$ and randomly reinsert it back into the deck. Pinsky [Probabilistic and combinatorial aspects of the card-cyclic-to-random shuffle (2011). Unpublished manuscript] introduced this shuffle and asked how many steps are needed to mix the deck. He showed $n$ steps do not suffice. Here we show that the mixing time is on the order of $\Theta(n\log n)$.
Large Stark effect for Li donor spins in Si

We study the effect of a static electric field on lithium donor spins in silicon. The anisotropy of the effective mass leads to the anisotropy of the quadratic Stark susceptibility, which we determined using the Dalgarno-Lewis exact summation method. The theory is asymptotically exact in the field domain below Li-donor ionization threshold, relevant to the Stark-tuning electron spin resonance experiments. To obtain the generalized Stark susceptibilities at arbitrary fields, we propose a new variational wave function, which reproduces the exact results in the low-field limit. With the calculated susceptibilities at hand, we are able to predict and analyze several important physical effects. First, we observe that the energy level shifts due to the quadratic Stark effect for Li donors in Si are equivalent to, and can be mapped onto, those produced by an external stress. Second, we demonstrate that the Stark effect anisotropy, combined with the unique valley-orbit splitting of a Li donor in Si, spin-orbit interaction, and specially tuned external stress may lead to a very strong modulation of the donor spin $g$ factor by the electric field. Third, we investigate the influence of random strains on the $g$ factor shifts and quantify the random strain limits and requirements to Si material purity necessary to observe the $g$-factor Stark shifts experimentally. Finally, we discuss possible implications of our results for quantum information processing with Li spin qubits in Si.
First Total Synthesis of a Fluorescent Didemnin

Abstract A dimethylaminocoumarin fluorophore was linked to didemnin A through a glycine tether. The resultant fluorescent didemnin will be used to study cellular localization as detected by fluorescence microscopy.
An FPGA-based design of a modular approach for integral images in a real-time face detection system

The first step in a facial recognition system is to find and extract human faces in a static image or video frame. Most face detection methods are based on statistical models that can be trained and then used to classify faces. These methods are effective but the main drawback is speed because a massive number of sub-windows at different image scales are considered in the detection procedure. A robust face detection technique based on an encoded image known as an "integral image" has been proposed by Viola and Jones. The use of an integral image helps to reduce the number of operations to access a sub-image to a relatively small and fixed number. Additional speedup is achieved by incorporating a cascade of simple classifiers to quickly eliminate non-face sub-windows. Even with the reduced number of accesses to image data to extract features in Viola-Jones algorithm, the number of memory accesses is still too high to support realtime operations for high resolution images or video frames. The proposed hardware design in this research work employs a modular approach to represent the "integral image" for this memory-intensive application. An efficient memory manage strategy is also proposed to aggressively utilize embedded memory modules to reduce interaction with external memory chips. The proposed design is targeted for a low-cost FPGA prototype board for a cost-effective face detection/recognition system.
Pet Overpopulation: An Economic Analysis

This paper considers the problem of pet overpopulation. It develops a tractable dynamic model whose positive predictions square well with key features of the current U.S. market for pets. The model is used to understand, from a welfare economic perspective, the sense in which there is \overpopulation" of pets and the underlying causes of the problem. The paper also employs the model to consider what policies might be implemented to deal with the problem. A calibrated example is developed to illustrate these corrective policies and quantify the welfare gains they produce.
Efficient Auctions and Interdependent Types

We consider the efficient allocation of a single good with interdependent values in a quasi-linear environment. We present an approach to modeling interdependent preferences distinguishing between "payoff types" and "belief types" and report a characterization of when the efficient allocation can be partially Bayesian implemented on a finite type space. The characterization can be used to unify a number of sufficient conditions for efficient partial implementation in this classical auction setting. We report how a canonical language for discussing interdependent types - developed in a more general setting by Bergemann, Morris and Takahashi (2011) - applies in this setting and note by example that this canonical language will not allow us to distinguish some types in the payoff type - belief type language.
Double Helix Value Functions, Ordinal/Cardinal Approach, Additive Utility Functions, Multiple Criteria, Decision Paradigm, Process, and Types (Z Theory I)

Z Utility Theory refers to a class of nonlinear utility functions for solving Risk and Multiple Criteria Decision-Making problems. Z utility functions are hybrids of additive and nonadditive (nonlinear) functions. This paper addresses the concepts and assessment methods for the additive part of Z-utility functions for multiple criteria problems that satisfy the efficiency (nondominancy) principle. We provide a decision paradigm and guidelines on how to approach, formulate, and solve decision-making problems. We, also, overview the modeling of decision process based on four types of decision-making styles. For multi-criteria problems, a new definition of convex efficiency is introduced. Also polyhedral efficiency is developed for presenting multi-criteria efficiency (nondominancy) graphically. New double helix quasi-linear value functions for multi-criteria are developed. Two types of double helix value functions for solving bi-criteria (Advantages versus Disadvantages) and also risk problems are introduced: Food–Fun curves for expected values and Fight-Flight curves for expected risk values. Ordinal/Cardinal Approach (OCA) for assessment of additive utility functions is developed. Simple consistency tests to determine whether the assessed utility function satisfies ordinal and/or cardinal properties are provided. We show that OCA can also be used to solve outranking problems. We provide a critique of Analytic Hierarchy Process (AHP) for assessing additive value functions and show that the developed Ordinal/Cardinal Approach overcomes the shortcomings of AHP. We also develop a unified/integrated approach for simultaneous assessment of nonlinear value and additive (multi-criteria) utility functions. These results in an additive utility function that can be concave, convex, or hybrid concave/convex based on the nonlinear value function. Finally, we show an interactive paired comparisons approach for solving nonadditive and nonlinear utility functions for bi-criteria decision-making problems. Several illustrative examples are provided. The paper provides reliable and robust approaches for modeling the utility preferences of heterogeneous economic agents in macro and micro-economics.
Cities and the organization of manufacturing

Abstract This paper provides some recent evidence on the distribution of manufacturing activity across cities in the US. For overall manufacturing, the number of establishments increases more than proportionally with city population, total employment increases in proportion to city population, and the employee size of an establishment is stochastically decreasing as city population increases. While these results are partly driven by the differences in industry composition across cities, for many industries larger cities tend to accommodate more employment through an expansion in the number of establishments, but not necessarily through an increase in average establishment size.
Natural convection experiments in a liquid-saturated porous medium bounded by vertical coaxial cylinders

An experimental effort is presently underway to investigate natural convection in liquid-saturated porous media utilizing a geometry and hydrodynamic/thermal boundary conditions relevant to the problem of nuclear-waste isolation in geologic repositories. During the first phase of this research program, detailed measurements were made of the steady state thermal field throughout an annular test region bounded by a vertical, constant-heat-flux inner cylinder and a concentrically placed, constant-temperature outer cylinder. An overlying, constant-pressure fluid layer was utilized to supply a permeable upper surface boundary condition. Results showed the heater surfae temperature to increase with increasing vertical distance due to the buoyantly driven upflow. The measured temperature difference (..delta..T) between the average heater surface temperature and the constant outer-surface temperature was found to be progressively below the straight-line/conduction-only solution for ..delta..T versus power input, as the latter was systematically increased. Comparisons between measured results and numerical predictions obtained using the finite element code MARIAH showed very good agreement, thereby contributing to the qualification of this code for repository-design applications.
The Political Economy of State Government Subsidy Adoption: The Case of Ethanol

In this paper we examine the factors that determine the adoption of state economic development incentives in the ethanol industry. We compile data on the implementation dates for subsidies/tax credits for all states for years 1984-2007, a period that covers the complete emergence of the biofuel industry in the United States and that was characterized by the passage of a numerous of state-level subsidies and tax breaks aimed at increasing ethanol production. Using Cox proportional hazard regression analysis, we find that states are more likely to adopt ethanol subsidies when corn production is high, when corn prices are low and gasoline prices are high, when a state is affiliated with the National Corn Growers Association, when a check-off is present, and when state government is under the control of Democrats.
Measuring the Sources of the Intergalactic Ionizing Flux

We use a wide-field (0.9 deg2) X-ray sample with optical and Galaxy Evolution Explorer (GALEX) ultraviolet observations to measure the contribution of active galactic nuclei (AGNs) to the ionizing flux as a function of redshift. Our analysis shows that the AGN contribution to the metagalactic ionizing background peaks at around z = 2. The measured values of the ionizing background from the AGNs are lower than previous estimates and confirm that ionization from AGNs is insufficient to maintain the observed ionization of the intergalactic medium (IGM) at z > 3. We show that only X-ray sources with broad lines in their optical spectra have detectable ionizing flux and that the ionizing flux seen in an AGN is not correlated with its X-ray color. We also use the GALEX observations of the GOODS-N region to place a 2σ upper limit of 0.008 on the average ionization fraction f ν(700 A)/f ν(1500 A) for 626 UV selected galaxies in the redshift range z = 0.9-1.4. We then use this limit to estimate an upper bound to the galaxy contribution in the redshift range z = 0-5. If the z ~ 1.15 ionization fraction is appropriate for higher-redshift galaxies, then contributions from the galaxy population are also too low to account for the IGM ionization at the highest redshifts (z > 4).
Application of novel phosphine oxazoline ligands in asymmetric allylations of 4-acyloxy-2-pentene derivatives

Abstract A library of novel phosphine oxazoline ligands 2 was tested in the asymmetric allylation of 4-acyloxy-2-pentenes 1 . High throughput screening techniques were employed to accelerate this process. The data accumulated allowed the extent of asymmetric induction to be correlated with the ligand substituent R and ligand-to-metal ratios.
Emission Measures and Electron Densities for the Solar Transition Region

I analyze high spectral resolution ultraviolet spectra (1200-2000 A) recorded by the Naval Research Laboratory slit spectrograph (S082-B) on the Skylab space station. The spectra were obtained from the quiet Sun, a polar coronal hole, and two active regions. One goal of this work is to determine electron densities and emission measures for transition region lines formed between about 3 × 104 K and 2.5 × 105 K, using the best available atomic data. The majority of these data were not available during the Skylab era. Another goal of this work is to compare results using two independent instrument calibrations that differ at the extreme short- and long-wavelength ends of the spectrograph's useful wavelength range. The overall shape of the emission measure distribution with temperature derived in this analysis is similar to that found from other data sets. However, as found by other researchers recently, I find significant discrepancies in emission measures obtained for ions that should be formed at the same temperature. Most of these discrepancies are independent of the calibration used and are also independent of the solar region and element abundances adopted. Apart from inaccuracies in atomic physics, some of the discrepancies may be real and may reflect the unresolved fine structure of the transition region. No indication of non-Maxwellian distributions was found from the lines analyzed. The temperatures of formation for transition region ions seem to be close to their predicted temperatures in ionization equilibrium, although the sample of temperature-sensitive diagnostics is very limited over the S082-B wavelength range. Derived electron pressures (product of electron density and temperature) in the different solar regions range from 9.0 × 1013 K cm-3 in a coronal hole up to 2.4 × 1016 K cm-3 in an active region.
Energy minimization using multiple supply voltages

We present a dynamic programming technique for solving the multiple supply voltage scheduling problem in both nonpipelined and functionally pipelined data-paths. The scheduling problem refers to the assignment of a supply voltage level (selected from a fixed and known number of voltage levels) to each operation in a data flow graph so as to minimize the average energy consumption for given computation time or throughput constraints or both. The energy model is accurate and accounts for the input pattern dependencies, re-convergent fanout induced dependencies, and the energy cost of level shifters. Experimental results show that using three supply voltage levels on a number of standard benchmarks, an average energy saving of 40.19% (with a computation time constraint of 1.5 times the critical path delay) can be obtained compared to using a single supply voltage level.
KH 15D: A Spectroscopic Binary

We present the results of a high-resolution spectroscopic monitoring program of the eclipsing pre–main-sequence star KH 15D that reveal it to be a single-lined spectroscopic binary. We find that the best-fit Keplerian model has a period P = 48.38 days, which is nearly identical to the photometric period. Thus, we find the best explanation for the periodic dimming of KH 15D is that the binary motion carries the currently visible star alternately above and behind the edge of an obscuring cloud. The data are consistent with the models involving an inclined circumstellar disk, as recently proposed by Winn et al. and Chiang & Murray-Clay. We show that the mass ratio expected from models of pre–main-sequence evolution, together with the mass constraints for the visible star, restrict the orbital eccentricity to 0.68 ≤ e ≤ 0.80 and the mass function to 0.125 M_☉ ≤ FM/sin^3i ≤ 0.5 M_☉.
Scaling analysis of the d = 3 random field Ising model

Abstract We present a Monte Carlo simulation of the d = 3 Ising model in a random magnetic field with values ±H on each lattice site. Calculations have been performed on cubic lattices with linear dimension L = 6, 8, 10 and 12, and several values of H. A finite-size scaling analysis of the data for H = 0.5, 0.75 and 1.0 is consistent with hyperscaling, and a correlation exponent v = 0.7 ± 0.1 . For H = 1.50, 1.75 and 2.0 some of the L = 12 data show a discontinuity as a function of the inverse temperature β. The implications of these results are discussed.
Extensions of local fields and truncated power series

Abstract Let K be a finite tamely ramified extension of Q p and let L / K be a totally ramified ( Z / p n Z ) -extension. Let π L be a uniformizer for L , let σ be a generator for Gal ( L / K ) , and let f ( X ) be an element of O K [ X ] such that σ ( π L ) = f ( π L ) . We show that the reduction of f ( X ) modulo the maximal ideal of O K determines a certain subextension of L / K up to isomorphism. We use this result to study the field extensions generated by periodic points of a p -adic dynamical system.
Image inversion and magnification by negative index prisms

Prism structures with negative index materials were investigated for their novel focusing properties such as image inversion and magnification. They reinforce the functions of flat lens and broaden the applications of negative index materials.
Quantizing the damped harmonic oscillator

We consider the Fermi quantization of the classical damped harmonic oscillator (dho). In past work on the subject, authors double the phase space of the dho in order to close the system at each moment in time. For an infinite-dimensional phase space, this method requires one to construct a representation of the CAR algebra for each time. We show that the unitary dilation of the contraction semigroup governing the dynamics of the system is a logical extension of the doubling procedure, and it allows one to avoid the mathematical difficulties encountered with the previous method.
Restricted rotation analogs of decarboxylated S-adenosylmethionine as inhibitors of polyamine biosynthesis.☆

Abstract The synthesis and preliminary biological evaluation of decarboxylated S-adenosylmethionine analogs 1 and 2 is described. In an L1210 cultured cell assay, these compounds, designed as conformationally restricted active site probes for spermidine and spermine synthase, exhibit LD 50 values of 0.1 and 1.0 mM, respectively. In addition, these compounds have significant effects on levels of cellular polyamines and S-adenosylmethionine.
Free-floating cryostat sections for immunoelectron microscopy: Bridging the gap from light to electron microscopy.

Frozen skin sections are routinely used for light microscopic immunohistochemical study of the skin basement membrane zone for two reasons: some skin basement membrane zone proteins are labile to routine chemical fixation, and skin is not amenable to vibratome sectioning. However, inherent limitations of conventional frozen sections, including compromised morphology and a requirement for glass slide-mounting, usually limit immunohistochemical study to the light microscopy level. In the present study, we introduce use of unfixed, free-floating cryostat sections for characterization of immunolocalizations of selected skin basement membrane proteins at both the light and electron microscopy level. The new procedure employs free-floating cryostat sections that can be processed as routine tissue specimens and can be subjected to a variety of special staining procedures including immunohistochemistry. Especially useful is the ease of progressive processing of the same tissue specimen from light microscopy to electron microscopy. In this regard, the method renders itself useful when results of immunolabeling experiments need to be elucidated quickly at histological and ultrastructural levels as required for diagnostic and accelerated investigative strategies. Microsc. Res. Tech. 54:246–253, 2001. © 2001 Wiley-Liss, Inc.
Probabilistic Main Bearing Performance for an Internal Combustion Engine

A probabilistic analysis is presented for studying the variation effects on the main bearing performance of an I.C. engine system, under structural dynamic conditions. For computational efficiency, the probabilistic analysis is based on surrogate models (metamodels), which are developed using the kriging method. An optimum symmetric Latin hypercube algorithm is used for efficient “space-filling” sampling of the design space. The metamodels provide an efficient and accurate substitute to the actual engine bearing simulation models. The bearing performance is based on a comprehensive engine system dynamic analysis which couples the flexible crankshaft and block dynamics with a detailed main bearing elastohydrodynamic analysis. The clearance of all main bearings and the oil viscosity comprise the random variables in the probabilistic analysis. The maximum oil pressure and the percentage of time within each cycle that a bearing operates with oil film thickness below a threshold value of 0.27μm at each main bearing constitute the system performance measures. Probabilistic analyses are first performed to calculate the mean, standard deviation and probability density function of the bearing performance measures. Subsequently, a probabilistic sensitivity analysis is described for identifying the important random variables. Finally, a reliability-based design optimization study is conducted for optimizing the main bearing performance under uncertainty. Results from a V6 engine are presented.
Voyager disk-integrated photometry of Io

Abstract Voyager full-disk images of Io, available at solar phase angle of α = 2−29° and 101−159°, allow comparisons of the satellite's near-opposition photometric behavior with Earth-based results and the determination of the phase curve out to very high phase angles. The near-opposition data were reduced iteratively for self-consistent phase and rotation curves in each Voyager filter; the resulting phase coefficients, geometric albedos, and rotational lightcurves are consistent with Earth-based findings, except for a previously noted tendency for Voyager to yield somewhat redder spectral information. The derived near-opposition phase coefficients, ranging between 0.016 and 0.024 mag/ deg, decrease with increasing wavelength, a trend weakly noted in some Earth-based observations. The full, α = 2−159° phase curves allow the first direct determination of the phase integral of Io at several wavelengths: q rises from ≈0.7 in the ultraviolet to ≈0.8 in the orange. Combination of the Voyager phase integrals with Earth-based albedo information leads to a best estimate of the bolometric Bond albedo of 0.50 ± 0.10, a value consistent with, but slightly below, previous estimates.
Constraints on the Emission and Viewing Geometry of the Transient Anomalous X-ray Pulsar XTE J1810-197

The temporal decay of the flux components of the transient anomalous X-ray pulsar XTE J1 810-197 following its 2002 outburst presents a unique opportunity to probe the emission geometry of a magnetar. Toward this goal, we model the magnitude of the pulsar's modulation in narrow spectral bands over time. Following previous work, we assume that the postoutburst flux is produced in two distinct thermal components arising from a hot spot and a warm concentric ring. We include general relativistic effects on the blackbody spectra due to gravitational redshift and light bending near the stellar surface, which strongly depend on radius. This affects the model fits for the temperature and size of the emission regions. For the hot spot, the observed temporal and energy-dependent pulse modulation is found to require an anisotropic, pencil-beamed radiation pattern. We are able to constrain an allowed range for the angles that the line of sight (psi) and the hot spot pole (xi) make with respect to the spin axis. Within errors, this is defined by the locus of points in the xi-psi plane that lie along the line [xi + beta(R)] [psi + [beta(R)] = const, where beta(R) is a function of the radius R of the star. For a canonical value of R = 12 km, the viewing parameters range from psi = xi = 37deg to (psi, xi) = (85deg, 15deg). We discuss our results in the context of magnetar emission models.
Scaling of losses with size and wavelength in nanoplasmonics and metamaterials

We show that, for the resonant metal-dielectric structures with sub-wavelength confinement of light in all three dimensions, the loss cannot be reduced considerably below the loss of the metal itself unless one operates in the far IR and THz regions of the spectrum or below. Such high losses cannot be compensated by introducing gain due to Purcell-induced shortening of recombination times. The only way low loss optical meta-materials can be engineered is with, as yet unknown, low loss materials with negative permittivity.
A study in man-machine interaction

The performance of users in man-machine interaction (MMI) is described in terms of a number of user- and machine-oriented parameters. The general linear model for experimental design is used as a model of the interaction. Performance measures are selected and a questionnaire developed to gauge user attitudes toward the man-machine system (MMS) and its environment. The interface parameters selected are hypothesized to have a significant effect on the performance and attitude measures.The effects of varying CRT display rates and output delays upon user performance and attitudes in a series of message retrieval tasks were evaluated experimentally. The results support the somewhat surprising conclusion that doubling the display rate from 1200 to 2400 baud produces no significant performance or attitude changes; increasing the variability of the output display rate produces both significantly decreased user performance and a poorer attitude towards system and interactive environment. The generally held notion that increasing output display rates is associated with better user performance is not supported.
Transport Phenomena in Two-Phase Micro-Channel Heat Sinks

The design and reliable operation of a two-phase micro-channel heat sink require a fundamental understanding of the complex transport phenomena associated with convective boiling in small, parallel coolant passages. This understanding is the primary goal of this paper. This goal is realized by exploring the following aspects of boiling in micro-channels: hydrodynamic instability, two-phase flow patterns, pressure drop, and convective boiling heat transfer. High-speed photographic methods were used to determine dominant flow patterns and explore as well as characterize hydrodynamic instabilities. Two types of dynamic instability were identified, a severe pressure drop oscillation and a mild parallel channel instability, and a simple method is recommended to completely suppress the former. Predictions of three popular two-phase pressure drop models and correlations were compared to micro-channel water data, and only a separated flow (Lockhart-Martinelli) correlation based on the assumption of laminar flow in both phases gave acceptable predictions. Several popular heat transfer correlations were also examined and deemed unsuitable for micro-channel heat sinks because all these correlations are based on turbulent flow assumptions, and do not capture the unique features of micro-channel flow such as abrupt transition to slug flow, hydrodynamic instability, and high droplet entrainment in the annular regime. These findings point to the need for further study of boiling behavior and new predictive tools specifically tailored to micro-channel heat sinks.Copyright © 2002 by ASME
Chiral symmetry in nuclei

Abstract Effective field theory is considered to provide a highly useful framework for connecting nuclear physics with the symmetries and dynamics of the underlying theory of strong interactions, QCD. Of many issues that are of great current interest in this domain, I concentrate here on two: (1) A new class of ab initio calculations of observables in two-nucleon systems; (2) Attempts to extend chiral perturbation calculations to higher-order terms.
The True and Only Heaven: Progress and Its Critics

Can we continue to believe in progress? In this sobering analysis of the Western human condition, Christopher Lasch seeks the answer in a history of the struggle between two ideas: one is the idea of progress - an idea driven by the conviction that human desire is insatiable and requires ever larger production forces. Opposing this materialist view is the idea that condemns a boundless appetite for more and better goods and distrusts "improvements" that only feed desire. Tracing the opposition to the idea of progress from Rousseau through Montesquieu to Carlyle, Max Weber and G.D.H. Cole, Lasch finds much that is desirable in a turn toward moral conservatism, toward a lower-middle-class culture that features egalitarianism, workmanship and loyalty, and recognizes the danger of resentment of the material goods of others.
What is the Relationship Between Spermatozoa per Milliliter at Adulthood and the Tubular Fertility Index at Surgical Age for Patients With Cryptorchidism

Between 1971 and 1996, 1,550 children with cryptorchidism operated on in the Miguel Servet Children’s Hospital in Zaragoza were studied. The age ranged from newborn to 14 years, making a total of 2,249 testicles studied. A letter was sent to all patients older than 18 years (946 cases) who were operated on for cryptorchidism. Two hundred eight (26%) consented to be studied. We performed a physical examination, hypophisq axis study, testicular ultrasound study, and semen analysis according to the World Health Organization (WHO) norms.’ Both testis were biopsied at surgical procedure in 21 unilateral and 41 bilateral cryptorchidism patients. We then obtained a spermiogram when these children became adults (over 18 years). The testicle classification according to the position, the percentage of patients who received CGh treatment, the surgical technique used for the orchidopexy, and the anatomopathological protocol were described in a previous article.2
Block-structured solution scheme for analyzing three-dimensional transonic potential flows

Le schema est base sur la resolution des equations d'ecoulement potentiel pour des blocs individuels representant des sous-volumes du champ d'ecoulement
Silanediol-Catalyzed Carbon Dioxide Fixation

Carbon dioxide is an abundant and renewable C1 source. However, mild transformations with carbon dioxide at atmospheric pressure are difficult to accomplish. Silanediols have been discovered to operate as effective hydrogen-bond donor organocatalysts for the atom-efficient conversion of epoxides to cyclic carbonates under environmentally friendly conditions. The reaction system is tolerant of a variety of epoxides and the desired cyclic carbonates are isolated in excellent yields.
Spherical Collapse with Dark Energy

I discuss the work of Maor and Lahav (JCAP 0507:003, 2005), in which the inclusion of dark energy into the spherical collapse formalism is reviewed. Adopting a phenomenological approach, I consider the consequences of (a) allowing the dark energy to cluster, and, (b) including the dark energy in the virialization process. Both of these issues affect the final state of the system in a fundamental way. The results suggest a potentially differentiating signature between a true cosmological constant and a dynamic form of dark energy. This signature is unique in the sense that it does not depend on a measurement of the value of the equation of state of dark energy.
Fermionic sum representations for conformal field theory characters

Abstract We present sum representations for all characters of the unitary Virasoro minimal models. They can be viewed as fermionic companions of the Rocha-Caridi sum representations, the latter related to the (bosonic) Feigin-Fuchs-Felder construction. We also give fermionic representations for certain characters of the general ( G (1) ) k × ( G (1) ) l ( G (1) ) k+l coset conformal field theories, the non-unitary minimal models M (p, p+2) and M (p, kp+1) , the N = 2 superconformal series, and the Z N -parafermion theories, and relate the q →1 behaviour of all these fermionic sum representations to the thermodynamic Bethe ansatz.
The holographic RG flow in a field theory on a curved background

As shown by Freedman, Gubser, Pilch and Warner, the RG flow in = 4 super-Yang-Mills theory broken to an = 1 theory by the addition of a mass term can be described in terms of a supersymmetric domain wall solution in five-dimensional = 8 gauged supergravity. The FGPW flow is an example of a holographic RG flow in a field theory on a flat background. Here we put the field theory studied by Freedman, Gubser, Pilch and Warner on a curved AdS4 background, and we construct the supersymmetric domain wall solution which describes the RG flow in this field theory. This solution is a curved (non-Ricci flat) domain wall solution. This example demonstrates that holographic RG flows in supersymmetric field theories on a curved AdS4 background can be described in terms of curved supersymmetric domain wall solutions.
(E)-5-(3-oxopropen-1-yl)-2′-deoxyuridine and (E)-5-(3-oxopropen-1-yl)-2′,3′-dideoxyuridine; new antiviral agents: Syntheses and biological activity

Abstract The synthese of the 5-(3-oxopropen-1-yl) derivatives of dU ( 5 ) and ddU ( 6 ) and their biological activity are reported. Good antiviral activity (EC50, 1.4 μg/mL) and selectivity (SI > 71.4) is shown by 5 against VZV, whereas in the case of 6 the antiviral activity (EC50, 2.6 μg/mL; SI > 38.5) against EBV is greater than that of Acyclovir (EC50, 9.3 μg/mL).
Sertoli Cell Tumors of the Testis, Not Otherwise Specified. A Clinicopathologic Analysis of 60 Cases

Sixty Sertoli cell tumors of the testis, excluding large cell calcifying and sclerosing subtypes, are described. Patient age ranged from 15 to 80 years (mean, 45 years). The initial manifestation was usually a testicular mass; in 14 cases it had been enlarging slowly for a period of up to 14 year
Convective Babcock-Leighton Dynamo models

We present the first global, three-dimensional simulations of solar/stellar convection that take into account the influence of magnetic flux emergence by means of the Babcock-Leighton (BL) mechanism. We have shown that the inclusion of a BL poloidal source term in a convection simulation can promote cyclic activity in an otherwise steady dynamo. Some cycle properties are reminiscent of solar observations, such as the equatorward propagation of toroidal flux near the base of the convection zone. However, the cycle period in this young sun (rotating three times faster than the solar rate) is very short ({approx}6 months) and it is unclear whether much longer cycles may be achieved within this modeling framework, given the high efficiency of field generation and transport by the convection. Even so, the incorporation of mean-field parameterizations in three-dimensional convection simulations to account for elusive processes such as flux emergence may well prove useful in the future modeling of solar and stellar activity cycles.
Taylor rules with real-time data: A tale of two countries and one exchange rate ☆

Abstract Using real-time data that reflects information available to monetary authorities at the time they are formulating policy, we find that estimated Taylor rules based on revised and real-time data differ more for Germany than for the U.S., Taylor rules using real-time data suggest differences between U.S. and German monetary policies, and Taylor rules for the U.S. using inflation forecasts are nearly identical to those using lagged inflation rates. Evidence of out-of-sample predictability for the dollar/mark nominal exchange rate with forecasts based on Taylor rule fundamentals is only found with real-time data and does not increase if inflation forecasts are used.
Incipient failure in sandpile models

Abstract Elastoplastic and constitutive equation theories are two approaches based on very different assumptions for creating a continuum theory for the stress distributions in a static sandpile. Both models produce the same surprising prediction that in a two-dimensional granular pile constructed at its angle of repose, the outside wedge will be on the verge of failure. We show how these predictions can be tested experimentally.
2-Quinolinecarboxaldehyde : an unusual partner in the Henry reaction and subsequent elimination

2-Quinolinecarboxaldehyde participates in a standard Henry reaction when combined with a nitroalkane and catalytic amounts of base. However, water is not readily eliminated from the resulting β-nitro alcohol intermediate to form the expected nitroalkene. Instead, the elimination of nitrous acid is observed furnishing an unexpected ketone product.
Immunotherapeutic Potential of Oncolytic Vaccinia Virus

The concept of oncolytic viral therapy was based on the hypothesis that engineering tumor-selectivity into the replication potential of viruses would permit direct destruction of tumor cells as a result of viral-mediated lysis, resulting in amplification of the therapy exclusively within the tumor environment. The immune response raised by the virus was not only considered to be necessary for the safety of the approach, but also something of a hindrance to optimal therapeutic activity and repeat dosing. However, the pre-clinical and subsequent clinical success of several oncolytic viruses expressing selected cytokines has demonstrated the potential for harnessing the immune response as an additional and beneficial mechanism of therapeutic activity within the platform. Over the last few years, a variety of novel approaches have been incorporated to try to enhance this immunotherapeutic activity. Several innovative and subtle approaches have moved far beyond the expression of a single cytokine transgene, with the hope of optimizing anti-tumor immunity while having minimal detrimental impact on viral oncolytic activity.
Effects of external boundary layer flow on jet noise in flight

The effects on jet flow of the external boundary-layer flow emanating from the trailing edge of an engine cowl in flight has been shown to be the main reason for the disparity between predicted and experimental results obtained from flight measurements. Flight simulation experiments indicate that the external boundary-layer flow tends to shield the jet flow in flight. This in turn modifies the jet noise source in flight and consequently the radiated noise from aircraft in flight. Close to 0/ = 90° and in the forward quadrant, this study indicates that the far-field jet noise and its spectrum scales approximately with the absolute jet velocity instead of the relative velocity as has been assumed in the existing prediction models.
The Tutor's Story: A Case Study of Mixed Authorship

The Victorian author Charles Kingsley (1819–1875) left a manuscript of part of a novel unfinished when he died in 1875. His daughter, Mary St. Leger Kingsley Harrison (1852–1931), who wrote under the name Lucas Malet, discovered the manuscript, finished the novel, and published it in 1915. In her preface, Malet describes the state, size, and nature of the manuscript, and this description gives a fairly solid basis for assigning at least parts of the novel to the two authors. She tells us that the beginning of the manuscript, and so presumably also the novel, was ‘‘fairly consecutive,'' so that we can expect the early chapters to be Kingsley's. But she also tells us that there were other ‘‘chapters and skeletons of chapters'' from much later in the story, without further indicating where these occur in the novel. Finally, she reports that the plot was unresolved, and that she doubled the size of the text in completing it. This suggests that the late chapters of the novel are probably mostly by Malet. This ...
Asymptotic freedom in the early big-bang and the isotropy of the cosmic microwave background

It is suggested that a superunified field theory incorporating gravity and possessing asymptotic freedom could provide a solution to the problem of the isotropy of the universal 3 K background radiation. Thermal equilibrium could be established in this context through interactions occurring in a temporally indefinite pre-Planckian era.
Reactions of the fluorinating agent CF3OF with amino acid derivatives and peptides

Abstract A number of Hydrophobic acyl amino acid esters were fluorinated using CF 3 OF, yielding N -fluoroamides. The 1 H, 13 C and 19 F nuclear magnetic resonance (NMR) data for these compounds are reported. The first 14 N NMR spectrum of an N -fluoroamide is also reported, namely that of N -acetyl- N -fluoroglycine ethyl ester. The 14 N resonance of the fluorinated compound was shifted downfield by over 100 ppm from that of the starting material. Reaction of CF 3 OF with N -acetylleucine ethyl ester yielded the N -fluoroamide, as well as the compound in which the γ-hydrogen of leucine is replaced by fluorine. Treatment of the cyclopentapeptide c-(gly-pro-gly- d -ala-pro) with CF 3 OF yielded an intractable mixture of fluorinated hydrocarbons, N -fluoroamides and difluoroamides. Separation of the mixture resulting from treatment of N -acetylproline with CF 3 OF led to recovery of a fraction whose 19 F NMR spectrum indicated fluorination at the proline nitrogen and subsequent opening of the proline ring. Treatment of the cyclopentapeptide c- (gly-leu-gly-gly-gly) with CF 3 OF proceeded to a very limited extent, with the resulting mixture of N -fluoroamides showing no preference for fluorination at a specific site.