cssi/SciSciGPT-SciSciNet huggingface dataset:
Conjecture on the effect of small anharmonicity on vibrational modes of glass

Abstract We conjecture here that, unlike for crystal lattice modes, some nearly harmonic vibrational modes of a glass lattice may have their (thermally populated) energy levels shifted (from equal spacing) more than they are broadened, both the shifting and broadening arising from small anharmonic terms in the lattice potential. This conjecture could be verified by observing either (a) saturating infrared absorption, (b) an infrared photon echo, or (c) altered infrared absorption (possibly even gain) of a probe beam in the presence of a second pump beam.
South Sudan: institutional legacy of colonialism and the making of a new state

The paper argues that the post-colonial crisis of citizenship demands a rethinking of the paradigm of viewing colonialism simply as a system of economic exploitation to viewing colonialism as a political project that is anchored in law. The paper provides a historical and post-referendum analysis of the political division between North and South Sudan. As South Sudan seeks to build a state that accommodates diversity, it faces the same question faced in many African countries, namely how to build a nation that embraces diversity within the country and transcends the urban–rural divide and the ethnic divisions that threaten to undermine the process of nation-building. In Africa, the law has emerged as the tool that distinguishes and divides between those regarded as natives and thus entitled to political rights and access to resources and those considered non-native for whom political rights and access to resources are withheld. The paper discusses the challenges that South Sudan faces in building a nation...
Martian surface harmonics and continental drift

Abstract Recent radar and spectroscopic determinations of topographic heights on Mars reveal that the planet possesses a distribution of surface harmonics similar to that of the Earth. This similarity is manifested in the dominance of the first five harmonics with a rapid decline of higher order terms. An independent study of the Martian grid pattern, composed of lineaments known as the “Martian canals”, indicates the possible presence of convection currents within the Martian mantle. The distribution of areas of rising and descending currents provides a rough estimate of the stress fields in the Martian crust which can explain the position of the sub-equatorial dark maria, a zone now known to be partly composed of continental-type blocks, in terms of a southerly continental drift. These stress regions also suggest that the northern hemisphere feature Mare Acidalium could have formed in a manner similar to the convection hypothesis of the origin of terrestrial mid-oceanic ridges, that the south pole may be a mountainous area, and in general that the Martian linear features are related to tectonic zones of weakness. Other observed features also find a natural explanation in their origin in terms of the harmonics of an internal convection pattern. In this category may be included those surface features recently detected by the author with the aid of CO2 abundance measurements over discrete areas of the planet in light reflected in the 1.05 μm band.
Intramolecular Anodic Olefin Coupling Reactions: The Use of Allylsilane Coupling Partners with Allylic Alkoxy Groups.

Intramolecular anodic olefin coupling reactions having an alkoxy substituent on the allylic carbon of an allylsilane moiety have been studied. These substrates were examined as part of an effort to determine the compatibility of the anodic olefin coupling reaction with the presence of very acid-sensitive functional groups and the construction of functionalized five-membered rings. In the initial experiment reported, an enol ether moiety was coupled to a trisubstituted allylsilane to afford a five-membered ring product without loss of the allylic alkoxy group. The reaction was stereoselective and could be used to generate a five-membered ring with three contiguous asymmetric centers. The stereochemical outcome of the reaction was best explained by a “pseudoequatorial” alkoxy group in the transition state; an argument that implied the reaction was under kinetic control. This suggestion was tested with the use of two electrolysis substrates that led to identical products through different transition states. ...
Capacity Scaling of Ad Hoc Networks with Spatial Diversity

This paper derives the exact outage probability and transmission capacity of ad hoc wireless networks with nodes employing multiple antenna diversity techniques. The analysis enables a direct comparison of the number of simultaneous transmissions achieving a certain data rate under different diversity techniques. Preliminary results derive the outage probability and transmission capacity for a general class of signal distributions which facilitates quantifying the gain for fading or non-fading environments. The transmission capacity is then given for uniformly random networks with path loss exponent alpha > 2 in which nodes: (1) perform maximal ratio transmission/combining on M antennas with Theta(M 2/alpha ) gains; (2) various antenna selection combining schemes which give appreciable but rapidly diminishing gains; and (3) orthogonal space-time block coding, for which there is only a small gain due to channel hardening. It is concluded that in ad hoc networks, beamforming performs best, selection combining performs well for smaller numbers of antennas, and that space-time block coding offers only marginal gains.
Theoretical Simulation of an Anomalous Response in a Torsional Oscillator

In a torsional oscillator, constructed by stretching a hollow cylindrical natural rubber member and connecting one end to a fly wheel and the other end to a fixed support, an anomalous behavior has been experimentally observed which is attributed to crystallization in the rubber. The anomalous behavior is observed when the rubber is stretched to more than 3.5 times its initial length and is characterized by a reduction in the period of the oscillator during stress relaxation. This indicates a gradual increase in the torsional rigidity of the rubber which can be explained by crystallization. Analyzing the response of the oscillator based on modeling the rubber as an incompressible isotropic elastic or viscoelastic material predicts a behavior opposite to that observed in the experiments. Using a model developed for characterizing mechanical response during crystallization in polymers, the anomalous behavior of the oscillator is reproduced.
Determinants of historic and cultural landmark designation: why we preserve what we preserve

There is much interest among cultural economists in assessing the effects of heritage preservation policies. There has been less interest in modeling the policy choices made in historic and cultural landmark preservation. This article builds an economic model of a landmark designation that highlights the tensions between the interests of owners of cultural amenities and the interests of the neighboring community. We perform empirical tests by estimating a discrete choice model for landmark preservation using data from Chicago, combining the Chicago Historical Resources Survey of over 17,000 historic structures with property sales, Census, and other geographic data. The data allow us to explain why some properties were designated landmarks (or landmark districts) and others were not. The results identify the influence of property characteristics, local socio-economic factors, and measures of historic and cultural quality. The results emphasize the political economy of implementing preservation policies.
Social Surplus Approach and Heterodox Economics

Given the emphasis on social provisioning in heterodox economics, two of its central theoretical organizing principles are the concepts of the total social product and the social surplus. This appears to link heterodox economics to the social surplus approach associated with the classical economists and currently with Sraffian economists. However, heterodox economics connects agency with the social surplus and the social product, which the Sraffians reject as they take the level and composition of the social product as given. Therefore the different theoretical approach regarding the social surplus taken in heterodox economics may generate a different but similar way of theorizing about a capitalist economy. To explore this difference is the aim of the article.
Soviet and Nazi economic planning in the 1930s

This paper argues that economic planning under Stalin and Hitler in the 1930s was essentially similar, both in process and outcome. Both economies had fixed prices and used coercion as part of a rather chaotic process of resource allocation; consumption in both countries was sacrificed to investment in heavy industry. Both economies can be thought of as socialist, and socialism in the 1930s was hardly more than military mobilization. The economy of the Soviet Union is distinguished from that of capitalist economies by having both public ownership of property and centralized economic planning. This two-dimensional classification gives rise to questions about intermediate cases, particularly now that the Soviet economy is in the process of change. Economies with public ownership of property but not planning have been analyzed under the label of market socialism. Economies with private ownership and central planning have suffered neglect by comparison. The Nazi and wartime economies are mentioned occasionally as examples, but little attention has been paid to them in this context. (For example, Pryor, 1985, p. 24, ) This paper compares the process of economic planning in Nazi Germany and Soviet Russia in the 1930s. I argue that there were many similarities between planning in the two economies. The commonalities derived in large part from the use of fixed prices and economic coercion. Planning in the Soviet Union was less well organized and planning in Nazi Germany was more organized than might be thought. Two implications follow from this finding. First, actual socialist planning in the 1930s was closer to military mobilization than the market socialism of Western theorists or postwar Yugoslavia. Although not a new view, this conclusion has dropped out of recent discussions of the Soviet economy and needs reemphasis (Gregory and Stuart, 1990) . Second, the Nazi economy shared many characteristics with the dominant socialist economy of the time. The National Socialists were socialist in practice as well as name. The investigation will proceed in three steps. I will look first at the inputs to planning: bureaucracy, fixed prices, economic incentives. Then I will examine the major outputs of planning: the growth of output, its composition, and the standard of living. Finally I will attempt to infer the planners* aims from their activities as well as their statements. A concluding section reiterates some important differences between the Nazi and Soviet economies.
Arithmetical properties of laplacians of graphs

Let denote any matrix. Thinking of M as a linear map , we denote by Im(M) the -span of the column vectors of M. Let e 1, …en denote the standard basis of and let Eij :=ei − ej , (i ν j). In this article, we are interested in the group , and in particular in the elements of this group defined by the images τ ij of the vectors Eij under the quotient . Most of this article is devoted to the study of the case where M is the laplacian of a graph. In this case, the elements τ ij have finite order, and we study how the geometry of the graph relates to these orders. We give in particular a criterion in terms of the topology of the graph to determine when such an element has order 1 or 2.
The exit distribution for iterated Brownian motion in cones

We study the distribution of the exit place of iterated Brownian motion in a cone, obtaining information about the chance of the exit place having large magnitude. Along the way, we determine the joint distribution of the exit time and exit place of Brownian motion in a cone. This yields information on large values of the exit place (harmonic measure) for Brownian motion. The harmonic measure for cones has been studied by many authors for many years. Our results are sharper than any previously obtained.
Seed-Seedling Conflicts, Habitat Choice and Patterns of Plant Recruitment

The ecological forces determining where within a landscape plants recruit and grow has been termed proximal habitat choice. Habitat choice is imposed first by a heterogeneous pattern of seed dispersal across the patches that make up the landscape and second by environmental variation that favors plant survival in some patches more than in others. Seedseedling conflicts can occur during both of these phases of habitat choice if conditions or traits that are favorable for seeds are unfavorable for seedlings. During the dispersal phase, smaller seeds may have a greater probability of dispersal than larger seeds, and thus a greater probability of escape from predation, but they contain fewer reserves for support of the establishing seedling. After dispersal, environmental characteristics of a given patch type that lead to disproportionately high seed survival may lead to disproportionately low seedling survival. Considering three hypothetical landscapes, each composed of five patch types, I demonstrate that seed-seedling conflicts can have a major impact on both the overall quantity of recruitment at the landscape level and on the distribution of recruitment among patches. Available empirical evidence suggests these conflicts may be widespread in natural systems. Given their potential importance and extent, seed-seedling conflicts may play a previously unrecognized role in habitat choice.
Effect of statistical fluctuation in Monte Carlo based photon beam dose calculation on gamma index evaluation

The γ-index test has been commonly adopted to quantify the degree of agreement between a reference dose distribution and an evaluation dose distribution. Monte Carlo (MC) simulation has been widely used for the radiotherapy dose calculation for both clinical and research purposes. The goal of this work is to investigate both theoretically and experimentally the impact of the MC statistical fluctuation on the γ-index test when the fluctuation exists in the reference, the evaluation, or both dose distributions. To the first order approximation, we theoretically demonstrated in a simplified model that the statistical fluctuation tends to overestimate γ-index values when existing in the reference dose distribution and underestimate γ-index values when existing in the evaluation dose distribution given the original γ-index is relatively large for the statistical fluctuation. Our numerical experiments using realistic clinical photon radiation therapy cases have shown that (1) when performing a γ-index test between an MC reference dose and a non-MC evaluation dose, the average γ-index is overestimated and the gamma passing rate decreases with the increase of the statistical noise level in the reference dose; (2) when performing a γ-index test between a non-MC reference dose and an MC evaluation dose, the average γ-index is underestimated when they are within the clinically relevant range and the gamma passing rate increases with the increase of the statistical noise level in the evaluation dose; (3) when performing a γ-index test between an MC reference dose and an MC evaluation dose, the gamma passing rate is overestimated due to the statistical noise in the evaluation dose and underestimated due to the statistical noise in the reference dose. We conclude that the γ-index test should be used with caution when comparing dose distributions computed with MC simulation.
The Role of Diffusive Shock Acceleration on Nonequilibrium Ionization in Supernova Remnant Shocks. II. Emitted Spectra

We present a grid of nonequilibrium ionization models for the X-ray spectra from supernova remnants undergoing efficient diffusive shock acceleration. The calculation follows the hydrodynamics of the blast wave as well as the time-dependent ionization of the plasma behind the shock. The ionization state is passed to a plasma emissivity code to compute the thermal X-ray emission, which is combined with the emission from nonthermal synchrotron emission to produce a self-consistent model for the thermal and nonthermal emission from cosmic-ray dominated shocks. We show how plasma diagnostics such as the G'-ratio of He-like ions, defined as the ratio of the sum of the intercombination, forbidden, and satellite lines to the resonance line, can vary with acceleration efficiency, and discuss how the thermal X-ray emission, when the time-dependent ionization is not calculated self-consistently with the hydrodynamics, can differ from the thermal X-ray emission from models which do account for the hydrodynamics. Finally, we compare the thermal X-ray emission from models which show moderate acceleration (~35%) to the thermal X-ray emission from test-particle models.
Ligand tuning in asymmetric catalysis: mono- and bis-phospholanes for a prototypical Pd-catalyzed asymmetric allylation reaction

Enantioselectivities and yields comparable to the best catalysts reported previously can be achieved in the addition of potassium dimethyl malonate to diphenylallyl acetate by the use of Pd(0) complexes of bis-phospholanes prepared from d-mannitol. By appropriate changes in the C2−C5 substituents, rare example of a useful monophosphine can also be prepared by a similar route. In both instances chirality of C3 and C5 oxygen seems to play a crucial role in the asymmetric induction.
Frequency and nature of the variant syndromes of autoimmune liver disease.

To determine the frequency and nature of variant syndromes in autoimmune liver disease, 162 patients with type 1 autoimmune hepatitis, 37 patients with primary biliary cirrhosis, and 26 patients with primary sclerosing cholangitis were assessed in a uniform fashion, and the strength of the original diagnosis was evaluated by use of a scoring system. Variant forms, including syndromes with autoimmune hepatitis and primary biliary cirrhosis (7%) or primary sclerosing cholangitis (6%) and autoimmune cholangitis (11%), were common in the 225 patients (18%). Individuals with autoimmune hepatitis and primary biliary cirrhosis entered remission during corticosteroid therapy as commonly as individuals with definite autoimmune hepatitis (75% vs. 64%, P = .5), and they responded better than patients with autoimmune hepatitis and primary sclerosing cholangitis (75% vs. 22%, P = .03) or autoimmune cholangitis (75% vs. 0%, P = .009). Patients with autoimmune hepatitis and primary sclerosing cholangitis had a higher frequency of a poor result than other variants (78% vs. 17%, P = .04), and they died of liver failure or required liver transplantation more often than patients with definite autoimmune hepatitis (33% vs. 8%, P = .05). None of the patients entering remission had serum alkaline phosphatase levels greater than twofold the reference value. In conclusion, variants of autoimmune liver disease are common. Corticosteroid therapy can be effective in patients with features of autoimmune hepatitis and primary biliary cirrhosis. A serum alkaline phosphatase level of less than twofold the reference value characterizes corticosteroid-responsive individuals.
Numerical modeling of the steady-state two-phase closed thermosyphon

Abstract The steady-state performance of the gravity-assisted, two-phase, closed thermosyphon was modeled from first principles. Liquid-film momentum advection and axial normal stress, typically neglected by previous investigators, were included and shown to be important to the thermosyphon performance. The model presented also expanded previous analyses to include both temperature and heat-flux controlled thermosyphons and thermosyphons with mixed or other external boundary conditions. Numerical techniques were incorporated to solve the nonlinear governing equations and respective boundary conditions. A series of thermosyphon experiments were conducted. Predictions from the model agree well with experimental results. The parametric effects of operating temperatures, geometry, working fluid inventory and condenser thermal capacity were studied. The model presented could be used for optimization studies and design of thermosyphons.
When should a firm expand its business?: The signaling implications of business expansion

Abstract We examine an incumbent's trade-off between the improved efficiency that business expansion facilitates and the signaling role that business expansion plays in conveying information to potential entrants about the state of demand. We demonstrate that both separating and pooling equilibria survive the Intuitive Criterion. Essentially, in contrast to models with asymmetric information about unit cost, incumbents' benefits from investing in a signal are not necessarily monotonic in the state of demand. We investigate how the extent of informativeness of the outcome depends on the enhanced efficiency that the incumbent's expansion facilitates and the priors of the entrant.
Lemur IIb: a Robotic System for Steep Terrain Access

To extract the full science potential from planetary surface operations, robots must be able to access the entire surface of the planetary body, not just the relatively level areas. Buoyed by the success of top-to-bottom strategies employing tethered robots, the stage is set for bottom-to-top technologies and techniques to be investigated. To this end, we have designed and built Lemur IIb, a 4-limbed robotic system that is being used to investigate several aspects of climbing system design including the mechanical system (novel end-effectors, kinematics, joint design), sensing (force, attitude, vision), low-level control (force-control for tactile sensing and stability management), and planning (joint trajectories for stability). The technologies developed on this platform will be used to build an advanced system that will climb slopes up to and including vertical faces and overhangs and be able to react forces to maintain stability and do useful work (e.g., sample acquisition/instrument placement). Among the most advanced of these technologies is a new class of Ultrasonic/Sonic Driller/Corer (USDC) end-effectors capable of creating “holds” in rock and soil as well as sampling those substrates. This paper lays out the mechanical, electrical, and algorithmic elements of the Lemur IIb robot and discusses the future directions of development in those areas.
Dust Grain Size Distributions from MRN to MEM

Employing the maximum entropy method (MEM) algorithm, we fit interstellar extinction measurements that span the wavelength range 0.125-3 μm. We present a uniform set of MEM model fits, all using the same grain materials, optical constants, and abundance constraints. In addition, we are taking advantage of improved UV and IR data and better estimates of the gas-to-dust ratio. The model fits cover the entire range of extinction properties that have been seen in the Galaxy and the Magellanic Clouds. The grain models employed for this presentation are the simplistic homogeneous sphere models (i.e., those of Mathis, Rumpl, & Nordsieck in 1977) with two (graphite, silicate) or three (graphite, silicate, amorphous carbon) components. Although such usage is only a first step, the results do provide interesting insight into the use of grain size as a diagnostic of dust environment. We find that the SMC bar extinction curve cannot be fitted using carbon grains alone. This is a challenge to the recent observational result indicating little silicon depletion in the SMC.
Electrically charged black-holes for the heterotic string compactified on a (10 - D)-torus

Abstract We show that the most general stationary electrically charged black-hole solutions of the heterotic string compactified on a (10 - D )-torus (where D > 3) can be obtained by using the solution generating transformations of Sen acting on the Myers and Perry metric. The conserved charges labeling these black-hole solutions are the mass, the angular momentum in all allowed commuting planes, and 36 − 2 D electric charges. General properties of these black-holes are also studied.
Aggressiveness and perennation of isolates of Cochliobolus heterostrophus from North Carolina

Selection occurring during the saprophytic or overwintering phase of the life cycle of Cochliobolus heterostrophus, the causal agent of southern leaf blight of maize, may be a factor in the persistence of apparently less aggressive isolates in the pathogen population. The relative aggressiveness and ability to perennate of 22 isolates of C. heterostrophus from North Carolina was measured in series of experiments. Significant differences in aggressiveness and percent perennation (overwintering survival) were observed. There was a weak but often significant negative correlation between the ability of isolates to persist on the soil surface and their aggressiveness. The ability of race O isolates to sporulate on senescent corn leaf discs was positively correlated with their aggressiveness. Selection against increased aggressiveness during overwintering does not appear sufficient by itself to counter selection for increased aggressiveness occurring during the pathogen's pathogenic phase.
First-principles computational discovery of materials for hydrogen storage

Hydrogen-fuelled vehicles require a cost-effective, lightweight material with precisely targeted thermodynamics and fast kinetics of hydrogen release. Since none of the conventional metal hydrides satisfy the multitude of requirements for a practical H2 storage system, recent research efforts have turned to advanced multicomponent systems based on complex hydrides. We show that first-principles density-functional theory (DFT) calculations have become a valuable tool for understanding and predicting novel hydrogen storage materials and understanding the atomic-scale kinetics of hydrogen release. Recent studies have used DFT calculations to (i) predict crystal structures of new solid-state hydrides, (ii) determine phase diagrams and thermodynamically favoured reaction pathways in multinary hydrides, and (iii) study microscopic kinetics of diffusion, phase transformations, and hydrogen release.
The environments of SLACS gravitational lenses

We report on an investigation of the environments of the Sloan Lens ACS Survey (SLACS) sample of gravitational lenses. The local and global environments of the lenses are characterized using Sloan Digital Sky Survey (SDSS) photometry and, when available, spectroscopy. We find that the lens systems that are best modelled with steeper than isothermal density profiles are more likely to have close companions than lenses with shallower than isothermal profiles. This suggests that the profile steepening may be caused by interactions with a companion galaxy as indicated by N-body simulations of group galaxies. The global environments of the SLACS lenses are typical of non-lensing SDSS galaxies with comparable properties to the lenses, and the richnesses of the lens groups are not as strongly correlated with the lens density profiles as are the local environments. Furthermore, we investigate the possibility of line-of-sight contamination affecting the lens models, but do not find a significant over-density of sources compared to lines of sight without lenses.
Initial Results in Using a Self-Coherence Method for Detecting Sustained Oscillations

This paper develops a self-coherence method for detecting sustained oscillations using phasor measurement unit (PMU) data. Sustained oscillations decrease system performance and introduce potential reliability issues. Timely detection of the oscillations at an early stage provides the opportunity for taking remedial reaction. Using high-speed time-synchronized PMU data, this paper details a self-coherence method for detecting sustained oscillation, even when the oscillation amplitude is lower than ambient noise. Simulation and field measurement data are used to evaluate the proposed method’s performance. It is shown that the proposed method can detect sustained oscillations and estimate oscillation frequencies with a low signal-to-noise ratio. Comparison with a power spectral density method also shows that the proposed self-coherence method performs better. Index Terms—coherence, power spectral density, phasor measurement unit (PMU), oscillations, power system dynamics
Noncanonical Hamiltonian formulation of ideal magnetohydrodynamics

Abstract A noncanonical Poisson structure for ideal magnetohydrodynamics is presented and identified with a differential Lie algebra.
Surprisingly Little O VI Emission Arises in the Local Bubble

This paper reports the first study of the O VI resonance line emission (λλ1032, 1038) originating in the Local Bubble (or Local Hot Bubble) surrounding the solar neighborhood. In spite of the fact that O VI absorption within the Local Bubble has been observed, no resonance line emission was detected during our 230 ks Far Ultraviolet Spectroscopic Explorer observation of a "shadowing" filament in the southern Galactic hemisphere. As a result, tight 2 σ upper limits are set on the intensities in the 1032 and 1038 A emission lines: 500 and 530 photons cm-2 s-1 sr-1, respectively. These values place strict constraints on models and simulations. They suggest that the O VI-bearing plasma and the X-ray emissive plasma reside in distinct regions of the Local Bubble and are not mixed in a single plasma, whether in equilibrium with T ~ 106 K or highly overionized with T ~ 4 to 6 × 106 K. If the line of sight intersects multiple cool clouds within the Local Bubble, then the results also suggest that hot/cool transition zones differ from those in current simulations. With these intensity upper limits, we establish limits on the electron density, thermal pressure, path length, and cooling timescale of the O VI-bearing plasma in the Local Bubble. Furthermore, the intensity of O VI resonance line doublet photons originating in the Galactic thick disk and halo is determined (3500-4300 photons cm-2 s-1 sr-1), and the electron density, thermal pressure, path length, and cooling timescale of its O VI-bearing plasma are calculated. The pressure in the Galactic halo's O VI-bearing plasma (3100-3800 K cm-3) agrees with model predictions for the total pressure in the thick disk/lower halo. We also report the results of searches for the emission signatures of interstellar C I, C II, C III, N I, N II, N III, Mg II, Si II, S II, S III, S IV, S VI, Fe II, and Fe III.
Derivation of an Analytical Approximation of the Spectrum of Spinning Dust Emission

An analytical function for the spectrum of spinning dust emission is presented. It is derived through the application of careful approximations, with each step tested against numerical calculations. This approach ensures accuracy while providing an intuitive picture of the physics. The final result may be useful for fitting of anomalous microwave emission observations, as is demonstrated by a comparison with the Planck observations of the Perseus Molecular Cloud. It is hoped that this will lead to a broader consideration of the spinning dust model when interpreting microwave continuum observations, and that it will provide a standard framework for interpreting and comparing the variety of anomalous microwave emission observations.
Impact of sourcing flexibility on the outsourcing of services under demand uncertainty

Abstract This paper investigates the relationship between market conditions and the value and use of sourcing flexibility for service processes. We develop and analyze a series of models, and we derive expressions for the optimal switching decision, the value of the option to outsource, the value of the option to backsource, and the probability and timing of switches between the alternative sources. One contribution is the models and associated derivations, which are largely new to the literature and may serve as a tool to support service sourcing plans and decisions. The second contribution is a series of results with managerial implications: (1) The probability of outsourcing is generally increasing in volatility for high-skill process and decreasing in volatility for low-skill processes. Earlier work has found that the hysteresis band is increasing in volatility, which is interpreted as an indicator of increasing organizational inertia. We also find that the hysteresis band is increasing in volatility, but interestingly for the case of high-skill processes, organizational inertia tends to be decreasing in volatility. (2) The option to backsource is generally more valuable for high-skill processes than for low-skill processes. This result suggests that investments to make it easier to backsource should have a higher priority for high-skill processes. (3) The value of the option to backsource a high-skill service process can be decreasing in volatility. The result suggests that a rather nuanced consideration of volatility is in order when considering investments in the flexibility to backsource a high-skill process.
Probing quarkonium production mechanisms with jet substructure

We use fragmenting jet functions (FJFs) in the context of quarkonia to study the production channels predicted by NRQCD (3 S 1 (1) , 3 S 1 (8) , 1 S 0 (8) , 3 P (8) ). We choose a set of FJFs that give the probability to find a quarkonium with a given momentum fraction inside a cone-algorithm jet with fixed cone size and energy. This observable gives several lever arms that allow one to distinguish different production channels. In particular, we show that at fixed momentum fraction the individual production mechanisms have distinct behaviors as a function of the the jet energy. As a consequence of this fact, we arrive at the robust prediction that if the depolarizing 1 S 0 (8) matrix element dominates, then the gluon FJF will diminish with increasing energy for fixed momentum fraction, z, and z >0.5.
Splitting Atoms: Why Do Countries Build Nuclear Power Plants?

Why do countries build nuclear power plants? This article develops a series of arguments for national reliance on nuclear power relating to economic development, energy security, nuclear proliferat...
Relational database: a practical foundation for productivity

It is well known that the growth in demands from end users for new applications is outstripping the capability of data processing departments to implement the corresponding application programs. There are two complementary approaches to attacking this problem (and both approaches are needed): one is to put end users into direct touch with the information stored in computers; the other is to increase the productivity of data processing professionals in the development of application programs. It is less well known that a single technology, relational database management, provides a practical foundation for both approaches. It is explained why this is so.While developing this productivity theme, it is noted that the time has come to draw a very sharp line between relational and nonrelational database systems, so that the label "relational" will not be used in misleading ways. The key to drawing this line is something called a "relational processing capability."
SYNTHESIS AND BIOLOGY OF SUBSTITUTED 3'-PHENYL TAXOL ANALOGUES

Abstract A series of substituted 3′-phenyl taxol analogues, directed by the Topliss Operational Scheme, were synthesized and evaluated for their biological activity. The novel analogues were prepared from baccatin III and N-acyl β-lactams. Evaluation in the microtubule assembly assay and for cytotoxicity against B16 melanoma cells illustrated a modest influence of aromatic substitution on bioactivity.
Interaction of gold nanoparticles in barium titanate thin films.

A novel approach to control the grain size of oxide thin film materials has been investigated. Perovskite BaTiO3 shows interesting grain structures when deposited on gold predeposited, (111)-oriented, single-crystal SrTiO3 substrates. Solid oxide films grow epitaxially on patterned seed layers and show variations in grain size relative to the films deposited on SrTiO3 directly.
New gravity field for Mars fuels research

An new gravitational field model for Mars sheds new light on the structure and composition of many short-wavelength features on the planet's surface. The model, Goddard Mars Model-1 (GMM-1) (Figure 1), holds great promise for future Mars research. Besides resolving more short-wavelength features than previous Mars gravity models, most major features have higher magnitude anomalies. For example, GMM-1 details the Valles Marineris canyon near the center of the map and reveals structures of several major impact basins and shield volcanos never before observed. Interestingly, several prominent anomalies in GMM-1 fail to correlate with surface features. Two prominent anomalies of this type in the northern hemisphere (Ion=−160°, lat=+30° and Ion=105°, lat=+50°) may indicate features covered by volcanic flooding.
Automated segmentation of anatomic regions in chest radiographs using an adaptive-sized hybrid neural network

The purposes of this research are to investigate the effectiveness of our novel image features for segmentation of anatomic regions such as the lungs and the mediastinum in chest radiographs and to develop an automatic computerized method for image processing. A total of 85 screening chest radiographs from Johns Hopkins University Hospital were digitized to 2 K by 2.5 K pixels with 12 bit gray scale. To reduce the amount of information, the images were smoothed and subsampled to 256 by 310 pixels with 8 bit. The determination approach consists of classifying each pixel into two anatomic classes (lung and others) on the basis of several image features: (1) relative pixel address (Rx,Ry) based on lung edges extracted through image processing using profile, (2) density normalized from lungs and mediastinum density, and (3) histogram equalized entropy. The combinations of image features were evaluated using an adaptive-sized hybrid neural network consisting of an input, a hidden, and an output layer. Fourteen images were used for the training of the neural network and the remaining 71 images for testing. Using four features of relative address (Rx,Ry), normalized density, and histogram equalized entropy, the neural networks classified lungs at 92% accuracy against test images following the same rules as for the training images.
Structural estimates of the intergenerational education correlation

Using a structural dynamic programming model, we investigate the relative importance of family background variables and individual specific abilities in explaining cross-sectional differences in schooling attainments and wages. Each type of ability is the sum of one component correlated with family background variables and a residual (orthogonal) component which is purely individual specific. Household background variables (especially parents' education) account for 68% of the explained cross-sectional variations in schooling attainments, while ability correlated with background variables accounts for 17% and pure individual specific ability accounts for 15%. Interestingly, individual differences in wages are mostly explained by pure individual specific abilities as they account for as much as 73% of the explained variations in wages. Family background variables account for only 19%, while ability endowments correlated with family background account for 8%. Copyright © 2003 John Wiley & Sons, Ltd.
Boron Nitride Precursors — A Perspective

Research efforts conducted in the Chemistry Division of the Oak Ridge National Laboratory on the preparation of polymeric precursors to boron nitride are reviewed. They evolved from the preparation of powders, which contained significant amounts of residual carbon, derived from the pyrolysis of aminoborane polymers to relatively pure films produced by chemical vapor deposition using polymeric cyanoborane as a single source. Interesting C/B/N films were produced from the pyrolyses of volatile borazine derivatives, and a polymeric borazine intermediate produced denser boron nitride (BN) compact bodies when used as a binder as opposed to bulk BN compressed without a binder. The challenges of producing boron nitride fibers have been defined.
EQUIVARIANT CHOW COHOMOLOGY OF TORIC VARIETIES

We show that the equivariant Chow cohomology ring of a toric vari- ety is naturally isomorphic to the ring of integral piecewise polynomial functions on the associated fan. This gives a large class of singular spaces for which lo- calization holds in equivariant Chow cohomology with integer coe!cients. We also compute the equivariant Chow cohomology of toric prevarieties and general complex hypertoric varieties in terms of piecewise polynomial functions. If X = X(!) is a smooth, complete complex toric variety then the follow- ing rings are canonically isomorphic: the equivariant singular cohomology ring H ! T (X), the equivariant Chow cohomology ring A ! (X), the Stanley-Riesner ring SR(!), and the ring of integral piecewise polynomial functions PP ! (!). If X is simplicial but not smooth then H ! (X) may have torsion and the natural map from SR(!) takes monomial generators to piecewise linear functions with ra- tional, but not necessarily integral, coe"cients. In such cases, these rings are not isomorphic, but they become isomorphic after tensoring with Q. When X is not simplicial, there are still natural maps between these rings, for instance from A ! (X)Q to H ! (X)Q and from H ! T (X) to PP ! (!), but these maps are far
Stuck in Traffic (SiT) Attacks: A Framework for Identifying Stealthy Attacks That Cause Traffic Congestion

Recent advances in wireless technologies have enabled many new applications in Intelligent Transportation Systems (ITS) such as collision avoidance, cooperative driving, congestion avoidance, and traffic optimization. Due to the vulnerable nature of wireless communication against interference and intentional jamming, ITS face new challenges to ensure the reliability and the safety of the overall system. In this paper, we expose a class of stealthy attacks -- Stuck in Traffic (SiT) attacks -- that aim to cause congestion by exploiting how drivers make decisions based on smart traffic signs. An attacker mounting a SiT attack solves a Markov Decision Process problem to find optimal/suboptimal attack policies in which he/she interferes with a well-chosen subset of signals that are based on the state of the system. We apply approximate policy iteration algorithms to derive potent attack policies. We evaluate their performance on a number of systems and compare them to other attack policies including random, myopic and DoS attack policies. The generated policies, albeit suboptimal, are shown to significantly outperform other attack policies as they maximize the expected cumulative reward from the standpoint of the attacker.
Tandem Gold/Silver‐Catalyzed Cycloaddition/Hydroarylation of 7‐Aryl‐1,6‐enynes to Form 6,6‐Diarylbicyclo[3.2.0]heptanes

Mixtures of [{PCy2(o-biphenyl)}AuCl] and AgSbF6 catalyze the tandem cycloaddition/hydroarylation of 7-aryl-1,6-enynes with electron-rich arenes to form 6,6-diarylbicyclo[3.2.0]heptanes in good yield under mild conditions. Experimental observations point to a mechanism involving gold-catalyzed cycloaddition followed by silver-catalyzed hydroarylation of a bicyclo[3.2.0]hept-1(7)-ene intermediate.
Conversion of a whistler wave into a controllable helical wiggler magnetic field

Plasma in the presence of a static magnetic field supports a whistler wave. It is shown that when the static magnetic field is switched off, the energy of the whistler wave is converted into the energy of a helical wiggler magnetic field.
Health Care Rationing: What Does it Mean?

(1989). Health Care Rationing: What Does it Mean? Hospital Topics: Vol. 67, No. 1, pp. 31-34.
Structure and conformations of cyclohexene,1,4-cyclohexadiene, and 1,3-cyclohexadiene

Abstract The fully optimized structures for the molecules 1,4-cyclohexadiene, 1,3-cyclohexadiene, and cyclohexene have been calculated by the ab initio force method. The structure of 1,4-cyclohexadiene is planar, while 1,3-cyclohexadiene and cyclohexene both exist in nonplanar conformations with C2 symmetry.
REDEMPTIVE PASTS AND IMPERILED FUTURES: THE WRITING OF A SIKH HISTORY

This article examines the narrative frameworks of the Persian histories of the Sikhs commissioned by the East India Company. These texts are important sources for understanding the development of individual Sikh states in the late eighteenth century, however, very little is known about the information networks and scholarly practices of the authors of such texts. Using the Tarikh-i Ahwal-i Sikhan of Khushwaqt Rai, I examine the ways in which Rai created a narrative that emphasized the heroism of the Sikh chiefs in a way that departed from earlier Punjabi and Persian accounts of the Sikhs. Although the narrative voice of the text preserves a deliberate neutrality; in re-interpreting his Punjabi sources and silencing the negative portrayals of Sikhs from earlier Persian works, Khushwaqt Rai created a text that emphasized the individual agency and sovereignty of Sikh chiefs. The masked partiality of authors such as Rai, I argue, must be understood in terms of the location of the authors at the intersection o...
LV-Control of a high-purity distillation column

Abstract A realistic study of the LV-control of a high-purity distillation column is presented. Linear controllers designed based on a linearized model of the plant are found to yield acceptable performance also when there is model—plant mismatch. The mismatch can be caused by uncertainty on the manipulated inputs, nonlinearity and variations in reboiler and condenser holdup. The presence of input uncertainty makes the use of a steady-state decoupler unacceptable. The effect of nonlinearity is strongly reduced by using the logarithm of the compositions. A simple diagonal PI-controller is not sensitive to model—plant mismatch, but yields a response with a sluggish return to steady-state.
On the degree of regularity of generalized van der Waerden triples

Abstract Let 1 ⩽ a ⩽ b be integers. A triple of the form ( x , a x + d , b x + 2 d ) , where x , d are positive integers is called an ( a , b ) -triple. The degree of regularity of the family of all ( a , b ) -triples, denoted dor ( a , b ) , is the maximum integer r such that every r-coloring of N admits a monochromatic ( a , b ) -triple. We settle, in the affirmative, the conjecture that dor ( a , b ) ∞ for all ( a , b ) ≠ ( 1 , 1 ) . We also disprove the conjecture that dor ( a , b ) ∈ { 1 , 2 , ∞ } for all ( a , b ) .
DBP ylides: Wittig reagents for synthesis of E-alkenes from aldehydes

Abstract Phosphorus ylides based on the dibenzophosphole (DBP) ring system convert aldehydes into trans-disubstituted oxaphosphetanes with good to excellent selectivity. Decomposition at 70–110° affords alkenes with E:Z ratios from 6:1 to > 100:1.
Computation of low-speed compressible flows with time-marching procedures

Abstract : The extension of time-marching procedures to low Mach number and low Reynolds number conditions is considered. It is shown that the disparate speeds of the acoustic and particle waves prevents convergence at high Reynolds numbers while the requirement that both the Courant and the von Neumann numbers be of order one prevents convergence in very viscous flows. A perturbation expansion is used to introduce pseudo-acoustic waves that propagate at speeds similar to the particle speed at high Reynolds numbers and that allows both the inviscid and viscous time step parameters to be of order one at low Reynolds numbers. The resulting algorithm is shown to give convergence rates that are independent of either Mach number or Reynolds number over a range of five orders of magnitude in both parameters. Results are shown for strong heat addition in low speed flow encompassing this broad range of variables.