cssi/SciSciGPT-SciSciNet huggingface dataset:
Viewpoint: Understanding the Great Depression

Bernanke 2000; and James 2001). It is now commonplace to view the Depression from an international perspective and to test causal hypotheses by comparing the experiences of countries that endured more and less severe cyclical downturns. This is in contrast with the earlier generation of scholarship, notably the influential work of Friedman and Schwartz (1963) and Temin (1976), which viewed the Depression as centred in the United States and focused on shocks and policies in that country. Specific hypotheses associated with the global perspective continue to be disputed, but there seems little question that the international view serves as a point of departure for a growing portion of recent scholarship. Whether this new research has produced a scholarly consensus is another matter. In this paper I ask whether it is possible to arrive at such a consensus by synthesizing the old and new literatures. I describe a perspective that views the Great Depression as a global phenomenon, emphasizing linkages among countries and the destabilizing influence of the international monetary and financial system, but that at the same time acknowledges the uniquely important character of events and policies in the United States. I thereby suggest that the opposition between the 'old' and 'new' (or 'U.S.-centric' and 'global') views of the Great Depression may ultimately prove artificial. The task for macroeconomic and historical scholarship
Complete Supersonic Flowfields over Blunt Bodies in a Generalized Orthogonal Coordinate System

THE material presented herein is a continuation of a research effort1 which is directed toward developing a computer code which can compute full Navier-Stokes solutions around complete probelike configurations for a wide range of supersonic Mach numbers and Reynolds numbers. A key feature of this code is that it is programmed in a general orthogonal coordinate system2 which can be used to describe many different axisymmetric and two-dimensional shapes and can closely approximate planetary probe configurations. The advantage of such an approach is that it allows one to study realistic configurations in a computational field with easily implemented boundary conditions and a relatively simple coding effort. The governing equations for the laminar flow of a perfect gas are discretized using Cheng and Alien's3 method. The code is equipped to capture the bow shock or to treat it as a discontinuity which floats in the computational field. Both body and shock slip boundary conditions can be implemented. Good comparisons with experimental data and with other numerical methods have been achieved with this program using a grid of 51x50, some examples of which follow. Results on this grid remain consistently good for an approximate Reynolds number range Re^ :SO(104). As this limit is exceeded, some unexpected problem areas are encountered. Some of these problem areas are also discussed and possible causes and remedies are suggested. On the basis of this "total picture," the present code is considered a final product for the indicated Reynolds number range. For larger Reynolds numbers, these results suggest that the complexities associated with a nonorthogonal, nonanalytic coordinate system may be offset by the benefits of being able to make the computational mesh coarse or fine where needed. Contents Comparisons between the present method and experimental results of Tewfik and Giedt4 for pressure distribution and heat transfer on a cylinder are presented in Figs. 1 and 2. Shock and body slip conditions were used although the calculated effects of shock slip were negligible. The static pressure distribution along the wake centerline of a cylinder is compared to experimental data of McCarthy and Kubota5 in Fig. 3. The distributions near peak centerline pressure are also plotted for the previous cases and for a sphere to illustrate the effect of Reynolds number and shape. The overprediction of pressure downstream is most likely due to a lack of resolution
GAAP convergence or convergence Gap: unfolding ten years of accounting change

Purpose – The purpose of this paper is to add to the literature on accounting change in explaining a decade-long effort by the FASB and IASB to develop a set of global accounting standards accepted by markets worldwide. This research studies the effort as one of “convergence” in accounting standards and aims to bring theoretical and empirical clarity as to how we can conceptualize the notion of convergence. Design/methodology/approach – Through a longitudinal study of 23 key FASB-IASB projects undertaken between 2002 and 2011, this paper analyzes processes of accounting change using a blend of institutional theory and political economy. A process perspective provides a method to unfold variants of accounting change by identifying patterns that help us to understand the conditions for and characteristics of convergence. Findings – The author highlights specific variants of accounting change observed during the convergence effort – direct emulation, difference reduction and progressive redesign – as analogo...
CVD Growth of Boron Nitride Nanotubes

Multiwalled BN nanotubes are grown from nickel boride catalyst particles by chemical vapor deposition at 1000−1100 °C using borazine, B3N3H6, as the precursor. This precursor is generated in situ from molten salt that forms from mixtures of (NH4)2SO4, NaBH4, and Co3O4 at 300−400 °C. The BN nanotubes have concentric-tube structures, are free of internal closures, have crystalline walls, and exhibit lengths of up to ∼5 μm. The nanotubes often possess bulbous, flag-like, or club-like tip closures. A root-growth mechanism is proposed for the catalyzed process.
Institution and inequality: the hukou system in China

Abstract We examine the impact of China's hukou system, which is an institution controlling population movement, on social and economic outcomes at the individual level. Using data from a recent Chinese household survey, we find that people who obtained urban hukou late in their lives fared significantly less well than other urban residents. They have fewer years of education, are less likely to hold state sector jobs and to have employer-provided healthcare benefits, and are more likely to be self-employed or unemployed. A rural–urban comparison that controls for factors commonly believed to affect migration decision reveals that the two major contributing factors to rural–urban inequality are low educational attainment among rural population and low rewards to education in rural employment. Since the hukou system denies rural population the access to education and urban employment, we argue that the hukou system is a major contributing factor to rural–urban inequality. We also estimate the value of an urban hukou to rural individuals. Journal of Comparative Economics 33 (1) (2005) 133–157.
A de novo synthesis of ethyl 2-deoxy-l-ribosides

Abstract A short (7-step) and efficient synthesis of several derivatives of 2-deoxy- l -ribose 1 , e.g., the ethyl ribosides, 2abc , has been accomplished from achiral precursors.
Verification of concurrent programs: the automata-theoretic framework

Abstract Vardi, M.Y., Verification of concurrent programs: the automata-theoretic framework, Annals of Pure and Applied Logic 51 (1991) 79–98. We present an automata-theoretic framework to the verification of concurrent and nondeterministic programs. The basic idea is that to verify that a program P is correct one writes a program A that receives the computation of P as input and diverges only on incorrect computations of P. Now P is correct if and only if a program PA, obtained by combining P and A, terminates. We formalize this idea in a framework of ω-automata with a recursive set of states. This unifies previous works on verification of fair termination and verification of temporal properties.
A Development‐friendly Prioritisation of Doha Round Proposals

Agriculture looms large on the WTO's agenda. It was the first substantive item listed in the work programme of the Ministerial Declaration launching the Doha Round, and it was arguably at the centre of the failure at Cancun. Developing countries made it clear both before and during the Cancun meeting that progress on agriculture was their primary objective. Negotiations in other areas have received less attention and progressed more slowly. This paper considers that prioritisation, and suggests that the interests of developing countries in the current round of trade negotiations are much broader than is suggested by the narrow range of agricultural issues that have dominated negotiations. A true development round would require a significant reprioritisation of many areas of the WTO's current agenda.
Poisson-Lie T-duality: the path-integral derivation

We formulate Poisson-Lie T-duality in a path-integral manner that allows us to analyze the quantum corrections. Using the path-integral, we rederive the most general form of a Poisson-Lie dualizeable background and the generalized Buscher transformation rules it has to satisfy.
Scale effects in Schumpeterian models of economic growth

Early models of Schumpeterian growth incorporate scale effects predicting that large economies grow faster than small economies, and that population growth causes accelerating per capita income growth. An absence of clear empirical evidence for these scale effects has led some researchers to question the foundations underlying the Schumpeterian approach to growth. This paper reviews empirical evidence on the relationship between scale and growth, and recent attempts to construct Schumpeterian growth models without scale effects.
Efficiency and information aggregation in auctions with costly information

Consider an auction in which k identical objects are sold to n > k bidders who each have a value for one object which can have both private and common components to it. Private information concerning the common component of the object is not exogenously given, but rather endogenous and bidders face a cost to becoming informed. If the cost of information is not prohibitively high, then the equilibrium price in a uniform price auction will not aggregate private information, in contrast to the costless information case. Moreover, for a wide class of auctions if the cost of information is not prohibitively high then the objects can only be allocated in a weakly efficient sense, and then only if the equilibrium proportion of endogenously informed agents is vanishing as the economy grows. In spite of these results, it is shown that there is a mechanism for which there exist equilibria and for which (weak) efficiency is achieved as the economy grows in the face of endogenous information acquisition.
Rapid estimation of the range-Doppler scattering function

Under wide sense stationary uncorrelated scattering (WSSUS) conditions, the signal spreading due to a random channel may be described by the scattering function (SF). In an active acoustic system, the received signal is modeled as the superposition of delayed and Doppler spread replicas of the transmitted waveform. The SF completely describes the second-order statistics of a WSSUS channel and can be considered a density function that characterizes the average spread in delay and Doppler experienced by an input signal as it passes through the channel. The SF and its measurement will be reviewed. An estimator is proposed based on a two-dimensional (2-D) autoregressive (AR) model for the scattering function. In order to implement this estimator, we derive the conditional minimum variance unbiased estimator of the time-varying frequency response of a linear channel. Unlike conventional Fourier methods, the AR approach does not suffer from the usual convolutional smoothing due to the signal ambiguity function. Simulation results are given.
Extended Emission by Dust in the Dwarf Galaxy UGC 10445

We present Spitzer Space Telescope images of the isolated dwarf galaxy UGC 10445. The galaxy is detected at all photometric bands (3.6-160 μm), as well as in the Multiband Imaging Photometer for Spitzer (MIPS) spectral energy distribution mode (55-95 μm). We derive a star formation rate of 0.25 M☉ yr-1, based on Hα and infrared flux densities. There is over 106 M☉ of cold dust (T ~ 18 K) in the galaxy, represented by 160 μm emission, which extends to a larger radius than the ultraviolet (UV), optical, and near-infrared light. Such extended emission has been seen previously only in dwarf galaxies in cluster environments. We suggest that the source of heating for this dust is UV light, originating in star-forming complexes. To produce the large quantity of dust requires a higher rate of star formation in the past than is currently observed.
The California Planet Survey. III. A Possible 2:1 Resonance in the Exoplanetary Triple System HD 37124

We present new radial velocities from Keck Observatory and both Newtonian and Keplerian solutions for the triple-planet system orbiting HD 37124. The orbital solution for this system has improved dramatically since the third planet was first reported in Vogt et al. with an ambiguous orbital period. The period ambiguity is resolved, and the outer two planets have an apparent period commensurability of 2:1. A dynamical analysis finds both resonant and non-resonant configurations consistent with the radial velocity data and constrains the mutual inclinations of the planets to be <~30°. We discuss HD 37124 in the context of the other 19 exoplanetary systems with apparent period commensurabilities, which we summarize in a table. We show that roughly one in three well-characterized multiplanet systems has a apparent low-order period commensurability, which is more than would naively be expected if the periods of exoplanets in known multiplanet systems were drawn randomly from the observed distribution of planetary orbital periods.
Higher twist contributions to /R-hadron phenomenology in the light gluino scenario

Abstract The open light gluino window allows non-trivial higher-twist gluino contributions to the proton wave function. Using a two-component model originally developed for charm hadroproduction, higher-twist intrinsic gluino contributions to final-state R -hadron formation are shown to enhance leading-twist production in the forward x F region. We calculate R -hadron production at p lab =800 GeV in pp , p Be, and p Cu interactions with light gluino masses of 1.2 , 1.5 , 3.5 , and 5.0 GeV.
On the power of two-local random reductions

Abstract We show that any language that has a two-locally-random reduction in which the target functions are boolean is in NP⧸poly∩co-NP⧸poly. This extends and simplifies a result by Yao.
EFFECTS OF SLOW MASS TRANSFER WHEN USING MICROPOROUS ADSORBENTS IN GAS-- SOLID CHROMATOGRAPHY.

Abstract The elution behaviors of CH4, C2H6, n-C3H8, iso-C4H10, Ar. O2, N2, and SF6 were studied in A-type zeolites containing K+, Na+, Li+, Sr2+, Ca2+, and Mg2+ and on a 10X zeolite. Temperature- and flow-dependent tailing of peaks and changes in retention volume with flow rate were found for those adsorbates able only to partially penetrate the pores. When diffusivities were large enough to allow total access to the pores, molecular size and the degree of adsorption for the adsorbate had significant effects — on HETP values.
Procainamide-induced antinuclear antibodies in beagle dogs

Procainamide produces a high incidence of autoimmune reactions in humans. To establish an animal model, we treated three groups of beagle dogs with increasing doses of procainamide HCl (100 to 200 mg/kg) for 11 to 14 months. Sera were examined before and during treatment for antinuclear antibodies (ANA) at a 1:10 dilution by an indirect immunofluorescence assay. The first group of six dogs, which were 1 year old and born in our colony, remained generally negative for ANA. In the second group of four dogs, which were of the same origin but were 3 to 6 years old, two developed ANA after 4 months of treatment. The third group of four dogs were 3 to 6 years old and had been born in the FDA colony to parents originating from another source. These dogs developed ANA after 1 to 2 months and remained generally positive throughout the 11 months of treatment. Dogs of the control groups remained negative except for one that was ANA-positive on several occasions. Three of the ANA-positive treated dogs and the ANA-positive control dog had circulating immune complexes. Serum procainamide concentrations were comparable in dogs of each group; acetylprocainamide was not detected. No alterations were found in serum proteins or in the hemograms, and no clinical signs were seen. The data suggest that age plays a contributory role in the development of this autoimmune response in the dog.
Analysis of Solid Teflon Pulsed Plasma Thruster

Studies of the pulsed plasma thruster used for stationkeeping in the LES-6 satellite are described. Current waveforms were measured, from which circuit parameters were deduced, an energy balance made, and thrust was computed. Each current pulse ablates ^10~8 kg of Teflon (6 X 1016 molecules of C 2F4), exhausts it at 3000 m/sec (specific impulse 300 sec) with an impulse bit of 31.2 jj, N-sec (7 julb-sec). Langmuir probe measurements of electron density and temperature, a K-band microwave interferometer measure of density and collision frequency, spectroscopic analysis of ion species, and a Faraday cup measurement of ion velocity were all made. Ion velocities of approximately 40,000 m/sec indicate that the gas is only partially ionized. A thrust stand was constructed to measure impulse bit and specific impulse. The impulse bit is linear with capacitor energy (1.85 joules, normally). Modifications in the current return path to the capacitor which changes the magnetic field behind the exhaust were made. Specific impulse could be tripled, but impulse bit dropped by a like factor, with no improvement in efficiency.
Chemical removal of nitrate from water

HIGH levels of nitrate in ground water can pose a serious health risk. Reduction of nitrate to nitrite in the gut may cause methemoglobinaemia1both in newborn infants and in adults deficient in glucose-phosphate dehydrogenase2. Under abnormal circumstances, reduction to nitrite can also occur in the stomach to form N-nitrosamines, a postulated cause of stomach cancer3. Nitrate outflow onto shallow continental shelves can promote nearshore algal blooms. Both natural and anthropogenic sources contribute to nitrate pollution. In the United States4 and Europe5, legislation now specifies a maximum permissible nitrate level in drinking water. Techniques such as selective ion exchange6, reverse osmosis, electrodialysis and distillation exist to transfer nitrate between two bodies of water, but only biological processes are presently available for nitrate destruction. Here I describe a chemical process in which aluminium powder reduces nitrate to ammonia, nitrogen and nitrite. In a pH range of 9 to 10.5, selective reduction of nitrate relative to sulphate is possible, and between pH 9.1 and 9.3, loss of the reductant through decomposition of water can be minimized to less than 2%. Subsequent control of pH and concentrations of dissolved aluminium, nitrite and ammonia should be possible at a realistic cost, making this process potentially useful for combating nitrate pollution.
X-ray Absorption Fine Structure of Aged, Pu-Doped Glass and Ceramic Waste Forms

Abstract X-ray absorption spectroscopic (XAS) studies were performed on three compositionally identical, Pu-doped, borosilicate glasses prepared 15 years ago at different α-activities by varying the 239Pu/238Pu isotopic ratio. The resulting α-activities ranged from 1.9×107 to 4.2×109 Bq/g and have current, accumulated doses between 8.8×1015 to 1.9×1018 α-decays/g. Two ceramic, polycrystalline zircon (ZrSiO4) samples prepared 16 years ago with 10.0 wt% Pu was also investigated. Varying the 239Pu/238Pu isotopic ratio in these samples resulted in α-activities of 2.5×108 and 5.6×1010 Bq/g and current, accumulated doses of 1.2×1017 and 2.8×1019 α-decays/g. The multicomponent composition of the waste forms permitted XAS investigations at six absorption edges for the borosilicate glass and at three absorption edges for the polycrystalline zircons. For both waste forms, analysis of extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectra indicates that the local environment around the cations exhibits different degrees of disorder as a result of the accumulated α-decay dose. In general, cations with short cation-oxygen bonds show little effect from self-radiation whereas cations with long cation–oxygen bonds show a greater degree of disorder with accumulated α-decay dose.
Extinction limits of nonadiabatic, catalyst-assisted flames in stagnation-point flow

An idealized geometry corresponding to a premixed flame in stagnation-point flow is used to investigate the effects of catalysis on extending the extinction limits of nonadiabatic stretched flames. Specifically, a surface catalytic reaction is assumed to occur on the stagnation plane, thereby augmenting combustion in the bulk gas with an exothermic surface reaction characterized by a reduced activation energy. Assuming the activation energies remain large, an asymptotic analysis of the resulting flame structure yields a formula for the extinction limit as a function of various parameters. In particular, it is demonstrated that the presence of a surface catalyst can extend the burning regime, thus counterbalancing the effects of heat loss and flame stretch that tend to shrink it. The analysis is relevant to small-volume combustors, where the increased surface-to-volume ratio can lead to extinction of the nonadiabatic flame in the absence of a catalyst.
An ASIC methodology for mixed analog-digital simulation

A practical approach to high-speed, mixed, analog-digital simulation is described. The system, known as the Analog Modeling Package (AMP), comprises a range of models, Laplace transform algorithms, and supporting programs. AMP not only supports the analog modeling process, but also enables analog models to be simulated on any digital simulator that supports a C or Pascal model interface. Each of these key elements is detailed. The strengths of AMP are speed and a systematic method. User benefits include running the resulting models on existing workstations through the novel analog model linker. >
Cytoskeletal dynamics and transport in growth cone motility and axon guidance

Recent studies indicate the actin and microtubule cytoskeletons are a final common target of many signaling cascades that influence the developing neuron. Regulation of polymer dynamics and transport are crucial for the proper growth cone motility. This review addresses how actin filaments, microtubules, and their associated proteins play crucial roles in growth cone motility, axon outgrowth, and guidance. We present a working model for cytoskeletal regulation of directed axon outgrowth. An important goal for the future will be to understand the coordinated response of the cytoskeleton to signaling cascades induced by guidance receptor activation.
IMPROVED METHODOLOGY FOR AXIAL FORCE PREDICTION AT ANGLE OF ATTACK

Animproved semiempiricalmethod foraxialforcecalculation on missilecone gurationshasbeen developed. The methodusesthetheoreticalmethodscurrentlyusedintheU.S.NavalSurfaceWarfareCenter’ saeropredictioncode for zero angle-of-attack axial force computations and several wind-tunnel databases to compute changes in axial force at angle of attack. The method is applicable to bodies alone, wing‐ body, and wing‐ body‐ tail cone gurations for both zero and nonzero control dee ections. It has been developed to allow computation for angle of attack up to 90 deg at Mach numbers up to 20. However, it has been validated against data only to Mach number of 4.6 and angle of attack to 40 deg for all cone gurations. For body alone and wing‐ body cases, it has been validated to 90 deg angle of attack. Additional test data or Navier‐ Stokes computations would allow ree nement of the improved method. The new method has been compared with several existing techniques. The method was found to be as good as or better than existing techniques but more general than existing methods in terms of cone gurations and Mach numbers allowed for the method to be used.
An asymmetric route to fused carbocyclic systems via Diels-Alder reactions on chiral α,β-unsaturated bicyclic lactams

Abstract The cycloadducts from Diels-Alder reactions have been transformed into novel functionalized carbocycles 11 and 12 in high enantiomeric excess.
A route to chiral epoxypyrroloindoles via oxiranyl radical cyclization

Abstract An oxiranyl radical has been generated from a glycidic acid via the thiohydroxamic acid anhydride route. The radical has been shown to undergo cyclization, a process, which to our knowledge, has not been reported previously. The structure and the reactivity of the indole and dihydroindole products of the cyclization are discussed.
Contribution limits and the effectiveness of campaign spending

Much work on the apparent ineffectiveness on incumbent spending in congressional elections has hypothesized that the productivity of incumbent spending is low because incumbents operate on the “flat part” of their election returns function. Differences in campaign spending associated with state campaign finance laws allows for a test of this hypothesis because restrictions on campaign contributions tend to reduce campaign spending. Exploiting cross-state variation in campaign finance laws, this study tests whether campaign expenditures by state House candidates are more productive when candidates are subject to contribution limits. The results show that campaign expenditures by incumbents and challengers are more productive when candidates run in states with campaign contribution limits, as opposed to in states without limits. In states with contribution limits, incumbent spending and challenger spending are equally productive, and spending by both candidates is quantitatively important in increasing their vote shares.
On Algebraic Decoding of q-ary Reed-Muller and Product Reed-Solomon Codes

We consider a list decoding algorithm recently proposed by Pellikaan-Wu [8] for q-ary Reed-Muller codes R M q(l, m, n) of length n les qm when I les q. A simple and easily accessible correctness proof is given which shows that this algorithm achieves a relative error-correction radius of taules (1 - radiclqm-1 /n). This is an improvement over the proof using one-point Algebraic-Geometric codes given in [8]. The described algorithm can be adapted to decode Product-Reed- Solomon codes. We then propose a new low complexity recursive algebraic decoding algorithm for Reed-Muller and product-Reed-Solomon codes. Our algorithm achieves a relative error correction radius of tau < Pii=1 m(1 - radicki/q). This technique is then proved to outperform the Pellikaan-Wu method in both complexity and error correction radius over a wide range of code rates.
Task Routineness and Trade Policy Preferences

Understanding the formation of individual trade policy preferences is a fundamental input into the modeling of trade policy outcomes. Surprisingly, past studies have found mixed evidence that various labor market and industry attributes of workers affect their trade policy preferences, even though recent studies have found that trade policy can have substantial impacts on workers' incomes. This paper provides the first analysis of the extent to which task routineness affects trade policy preferences using survey data from the American National Election Studies. We find significant evidence that greater task routineness leads workers to be much more supportive of import restrictions, consistent with recent evidence on how trade openness puts downward pressure on employment and wages for workers whose occupations involve routine tasks. In fact, other than education levels, task routineness is the only labor market attribute that displays a robust correlation with individuals' stated trade policy preferences. We also provide evidence that there are some interactions between the economic and non-economic factors in our study. For example, women's trade policy views are much more invariant to their labor market attributes than men, suggesting that women's views on this issue are driven more by personal and ideological beliefs than men.
Evaluation of two crew module boilerplate tests using newly developed calibration metrics

The paper discusses an application of multi-dimensional calibration metrics to evaluate pressure data from water drop tests of the Max Launch Abort System crew module boilerplate. Specifically, three metrics are discussed: (1) a metric to assess the probability of enveloping the measured data with the model, (2) a multi-dimensional orthogonality metric to assess model adequacy between test and analysis, and (3) a prediction error metric to conduct sensor placement to minimise pressure prediction errors. Data from similar (nearly repeated) capsule drop tests show significant variability in the measured pressure responses. When compared to expected variability using model predictions, it is demonstrated that the measured variability cannot be explained by the model under the current uncertainty assumptions.
Modeling Solution of Nonlinear Dispersive Partial Differential Equations Using the Marker Method

A new method for the solution of nonlinear dispersive partial differential equations is described. The marker method relies on the definition of a convective field associated with the underlying partial differential equation; the information about the approximate solution is associated with the response of an ensemble of markers to this convective field. Some key aspects of the method, such as the selection of the shape function and the initial loading, are discussed in some detail.
A luminosity constraint on the origin of unidentified high energy sources

The identification of point sources poses a great challenge for the high energy community. We present a new approach to evaluate the likelihood of a set of sources being a Galactic population based on the simple assumption that galaxies similar to the Milky Way host comparable populations of gamma-ray emitters. We propose a luminosity constraint on Galactic source populations which complements existing approaches by constraining the abundance and spatial distribution of any objects of Galactic origin, rather than focusing on the properties of a specific candidate emitter. We use M31 as a proxy for the Milky Way and demonstrate this technique by applying it to the unidentified EGRET sources. We find that it is highly improbable that the majority of the unidentified EGRET sources are members of a Galactic halo population (e.g., dark matter subhalos), but that current observations do not provide any constraints on all of these sources being Galactic objects if they reside entirely in the disk and bulge. Applying this method to upcoming observations by the Fermi Gamma-ray Space Telescope has the potential to exclude association of an even larger number of unidentified sources with any Galactic source class.
Derivation of a temperature-dependent accommodation coefficient for use in modeling laser-induced incandescence of soot

This paper presents a derivation of an expression to estimate the accommodation coefficient for gas collisions with a graphite surface, which is meant for use in models of laser-induced incandescence (LII) of soot. Energy transfer between gas molecules and solid surfaces has been studied extensively, and a considerable amount is known about the physical mechanisms important in thermal accommodation. Values of accommodation coefficients currently used in LII models are temperature independent and are based on a small subset of information available in the literature. The expression derived in this study is based on published data from state-to-state gas-surface scattering experiments. The present study compiles data on the temperature dependence of translational, rotational, and vibrational energy transfer for diatomic molecules (predominantly NO) colliding with graphite surfaces. The data were used to infer partial accommodation coefficients for translational, rotational, and vibrational degrees of freedom, which were consolidated to derive an overall accommodation coefficient that accounts for accommodation of all degrees of freedom of the scattered gas distributions. This accommodation coefficient can be used to calculate conductive cooling rates following laser heating of soot particles.
Unconditionally stable explicit algorithms for nonlinear fluid dynamics problems

Abstract This paper describes novel explicit algorithms that are unconditionally stable. The algorithms are applied to some 1D convection and diffusion problems, including nonlinear problems. Algorithms such as these are of particular interest for massively parallel computers, where one is trying to minimize communications while at the same time maintain the stability properties normally associated with implicit schemes. It is shown how these stable algorithms can be applied in higher spatial dimensions and how they can be extended to problems defined on unstructured meshes.
New Oxides Showing an Intense Orange Color Based on Fe3+ in Trigonal-Bipyramidal Coordination

Hexagonal YIn(1-x)Fe(x)O(3) phases have been prepared and characterized. The coordination for the In/Fe site in this structure is trigonal-bipyramidal. The colors of the phases change from yellow to orange to dark red with increasing Fe content. Magnetic measurements confirm high-spin Fe(3+) for all phases.
Spin polarized photocurrent from quantum dots

We predict strong spin-polarization switching of the photocurrent signal obtained from a single, self-assembled quantum dot photodiode by tuning only the intensity of elliptically polarized light. In the nonlinear mechanism described here, elliptically polarized light creates an effective exchange channel between different exciton spin states through the biexciton state, as we demonstrate by both numerical and analytical methods. This effect can be used as a dynamical switch to invert the spin polarization of the extracted photocurrent. We further show that the effect persists in realistic ensembles of dots, making this a powerful technique to dynamically generate spin polarized electron currents.
On the Non-existence of an R -labeling

We present a family of Eulerian posets which does not have any R-labeling. The result uses a structure theorem for R-labelings of the butterfly poset.
Methods for finding feasible points in constrained optimization

Methods for finding feasible points are needed in some numerical optimization algorithms to initiate the search for a local minimum. Other methods perform more efficiently if a nearly feasible starting point is used. In addition, a feasible solution may be acceptable as the final design in some practical applications. Therefore, constraint correction methods are quite useful. Such methods based on penalty functions and primal approach are described and discussed. To gain insight into the methods a two-variable problem is used to analyze the methods. Several structural design problems are used to study the numerical behavior of the methods and compare their performance. It is concluded that, in general, the primal methods are more efficient than the penalty function methods. Also, no method has been found that is guaranteed to find a feasible point for general constrained nonlinear problems starting from an arbitrary point. In case a method fails, random points should be used to restart the procedure to search for a feasible point.
Modularity in organizational structure: the reconfiguration of internally developed and acquired business units

This paper explores changes in organizational structure and distinguishes between units' origins. Unit reconfiguration is the addition of units to, deletion of units from, and recombination of units within the firm. This study compares the reconfiguration of internally developed vs. acquired units, explores what forms of unit recombination are common, and observes whether firms pursue recombination before divestiture. Theoretical support is drawn from the dynamic capabilities perspective, research on modular organizational systems, and strategy–structure literature. The findings are that acquired and internally developed units serve different roles in the process of change, and that firms perceive reconfiguration to be beneficial. Copyright © 2006 John Wiley & Sons, Ltd.
Venusian channel formation as a subsurface process

[1] We constructed detailed geologic maps of channels within three widely separated regions using Magellan synthetic aperture radar (SAR) imagery and altimetry radar data in order to understand the operative processes involved in Venusian channel formation. Channels in each region cut topographic highs including ridges and shield edifices with no deflection of the channel course by surface topography. We argue that these relationships are difficult to reconcile with the widely held view that Venusian channels represent surface processes, whether constructional or erosional. We conclude that the channels evolved through subsurface fluid flow, which involved local stoping and transport of overlying material; that is, these channels were carved from below, rather than from above. We postulate that at least some Venusian channels form because of subsurface fluid flow along a shallow crustal interface that forms the boundary between overlying low backscatter surface materials and underlying basal materials. Fluid movement along the interface may facilitate piecemeal stoping and erosion of the local surface materials from below, eventually resulting in the formation of channel traces exposed at the surface. The low backscatter material which hosts the channels in this study also hosts abundant coalescing shields and associated deposits, which may represent shield terrain.
The dust properties of eight debris disk candidates as determined by submillimeter photometry

The nature of far-infrared dust emission toward main-sequence stars, whether interstellar or circumstellar, can be deduced from submillimeter photometry. We present JCMT/SCUBA flux measurements at 850 μm toward eight stars with large photospheric excesses at 60-100 μm. Five sources were detected at 3 σ or greater significance and one was marginally detected at 2.5 σ. The inferred dust masses and temperatures range from 0.033 to 0.24 M⊕ and 43-65 K, respectively. The frequency behavior of the opacity, τν ∝ νβ, is relatively shallow, β 1.5, that are more typical of interstellar cirrus. The confirmed disks all have inferred diameters 2'', most lie near the upper envelope of the debris disk mass distribution, and four are bright enough to be feasible for high-resolution imaging.
Local circular law for random matrices

The circular law asserts that the spectral measure of eigenvalues of rescaled random matrices without symmetry assumption converges to the uniform measure on the unit disk. We prove a local version of this law at any point \(z\) away from the unit circle. More precisely, if \( | |z| - 1 | \ge \tau \) for arbitrarily small \(\tau > 0\), the circular law is valid around \(z\) up to scale \(N^{-1/2+ {\varepsilon }}\) for any \({\varepsilon }> 0\) under the assumption that the distributions of the matrix entries satisfy a uniform subexponential decay condition.
The Electoral College and voter participation rates: Reply

This theoretical note argues that although both gross costs and possible gross benefits from the Electoral College can be identified, they cannot be compared in such a way as to generate a case that the Electoral College yields net benefits to society. In other words, the Electoral College system, pure and simple, artificially distorts behavior in a market where household preferences are to intended be expressed; although this distortion yields apparent benefits and costs, the existence of net benefits is not established. In sum, since the Electoral College system artificially distorts geographic voter participation rate patterns, the case needs to be made w y the system should be retained.
Dynamic Tensile Extrusion Response of Tantalum

The effects of the original rolling texture and impact velocity on the large-strain dynamic tensile extrusion process in a high-purity Ta have been investigated in a gas gun facility. A continuous increasing of the total elongation of the extruded Ta spheres with increasing impact velocities has been observed. The starting texture was found to influence the development of instabilities with little effect on the total elongation. Regardless of the starting textures and impact velocities, a strong fiber texture was developed along the extrusion direction and similar hardness increments were recorded in the recovered Ta segments. Dislocation analysis revealed a continuous evolution of the dislocation substructures from loose planar arrays, to microbands, to elongated cells structures, and to equiaxed subgrains as a function of deformation. The evolution process of the dislocation substructures is discussed in detail in correlation with the development of the microstructure as well as the texture.
Economic development and the transition to democracy a formal model

In this essay, we have developed a rational choice model to study the transition to democracy. Such a model implies that the change or maintenance of a political system is the result of rational decisions by individuals, interest groups, and political parties under specific constraints. Our analysis shows that political systems are critically dependent upon the level of economic development. If a nation is at the lower stage of economic development, and, particularly, if its citizenry is poorly educated, the nation would lean toward choosing a dictatorship. As the nation accumulates more and more reproducible capital, it will tend to move toward democracy. Similarly, the model shows that, as the cost of democracy becomes lower and lower over time, a democratic system is likely to be chosen as the political infrastructure for social and economic development.
Slow light propagation and amplification via electromagnetically induced transparency and four-wave mixing in an optically dense atomic vapor

We experimentally and theoretically analyze the propagation of weak-signal field pulses under the conditions of electromagnetically induced transparency (EIT) in hot Rb vapor, and study the effects of resonant four-wave mixing (FWM). In particular, we demonstrate that in a double-Λ system, formed by the strong control field with the weak resonant signal and a far-detuned Stokes field, both continuous-wave spectra and pulse propagation dynamics for the signal field depend strongly on the amplitude of the seeded Stokes field, and the effect is enhanced in optically dense atomic medium. We also show that the theory describing the coupled propagation of the signal and Stokes fields is in good agreement with the experimental observations.
On the Boundedness of Damped Strings and Beams with Boundary and Distributed Inputs

This paper proves the boundedness of boundary and distributed damped strings and Euler-Bernoulli beams under combined distributed and boundary inputs. Distributed viscous or Kelvin-Voigt damping or a translational boundary damper stabilize strings and beams. Pointwise bounded response is proven using the energy multiplier method. Without disturbances, the method proves strong exponential stability. With disturbances, the response is shown to be strongly bounded.
Buckling of arbitrary quadrilateral anisotropic plates

The problem of buckling of arbitrary quadrilateral anisotropic plates with different boundary conditions under combined in-plane loading is considered. A Rayleigh-Ritz method combined with a variational formulation and a first-order transverse-shear-deformation theory is used. The Ritz functions consist of polynomials which include «circulation» functions that impose various boundary conditions. Numerical results are obtained for isotropic, orthotropic, and anisotropic plates with skewed geometries and are compared with existing results that use series solutions and with results generated from finite element simulations
An operating system based on the concept of a supervisory computer

An operating system which is organized as a small supervisor and a set of independent processes are described. The supervisor handles I/O with external devices—the file and directory system—schedules active processes and manages memory, handles errors, and provides a small set of primitive functions which it will execute for a process. A process is able to specify a request for a complicated action on the part of the supervisor (usually a wait on the occurrence of a compound event in the system) by combining these primitives into a “supervisory computer program.” The part of the supervisor which executes these programs may be viewed as a software implemented “supervisory computer.” The paper develops these concepts in detail, outlines the remainder of the supervisor, and discusses some of the advantages of this approach.
The epigenetic regulator CXXC finger protein 1 is essential for murine hematopoiesis.

CXXC finger protein 1 (Cfp1), encoded by the Cxxc1 gene, binds to DNA sequences containing an unmethylated CpG dinucleotide and is an epigenetic regulator of both cytosine and histone methylation. Cxxc1-null mouse embryos fail to gastrulate, and Cxxc1-null embryonic stem cells are viable but cannot differentiate, suggesting that Cfp1 is required for chromatin remodeling associated with stem cell differentiation and embryogenesis. Mice homozygous for a conditional Cxxc1 deletion allele and carrying the inducible Mx1-Cre transgene were generated to assess Cfp1 function in adult animals. Induction of Cre expression in adult animals led to Cfp1 depletion in hematopoietic cells, a failure of hematopoiesis with a nearly complete loss of lineage-committed progenitors and mature cells, elevated levels of apoptosis, and death within two weeks. A similar pathology resulted following transplantation of conditional Cxxc1 bone marrow cells into wild type recipients, demonstrating this phenotype is intrinsic to Cfp1 function within bone marrow cells. Remarkably, the Lin−Sca-1+c-Kit+ population of cells in the bone marrow, which is enriched for hematopoietic stem cells and multi-potential progenitor cells, persists and expands in the absence of Cfp1 during this time frame. Thus, Cfp1 is necessary for hematopoietic stem and multi-potential progenitor cell function and for the developmental potential of differentiating hematopoietic cells.
Chandrasekhar and the History of Astronomy

Chandrasekhar's own books, papers, and oral history interviews make clear that he was generally more interested in the present and future of astrophysics than in its past. Nevertheless, late in his life and after his death, historians of science have somewhat entangled him in two supposedly controversial issues, one concerning precursors of his mass limit for degenerate stars and the other his relationship with Eddington. Neither story is an entirely happy one.
Are There Two Pulsar Emission Mechanisms

We show that "core" and "cone" pulsar emission profiles are connected, through standard theoretical models, to dynamical properties of the pulsar emission region. The models predict pair plasma formation only in pulsars which show core-type emission. Emission models which assume turbulence driven by relative velocities of the pair swarms probably apply to coral pulsars. If conal pulsars are pairless, however, a different emission mechanism is required for these objects.