cssi/SciSciGPT-SciSciNet huggingface dataset:
Between “Authoritarian” and “Empowered” slum relocation: Social mediation in the case of Ennakhil, Morocco

Over the past four decades, as urbanization has increased in the Global South, pressures have mounted apace to convert slums to higher value use. In spite of policy shifts towards including residents’ viewpoints, involuntary resettlement remains inherently conflictive on at least two levels: between residents and outside actors and among residents themselves. In this paper we present a social mediation approach that addresses these two levels of conflict, illustrating its application in a slum relocation program in Ennakhil, Morocco. Social mediation occupies a middle ground between an authoritarian, urban planning approach to relocation and resettlement programs that have community empowerment as an explicit objective. We argue that a clear emphasis on mediating conflict should be more widely incorporated in slum relocation and other development programs. While the social mediation approach has clear advantages over authoritarian approaches, it is also better suited than the empowerment approach for projects that, like involuntary resettlement, inherently generate conflict and limit the opportunities for disadvantaged groups to control decisions.
Controlling kink band morphology in block copolymers : Threshold criteria and stability

The initiation, structure, and dynamics of defects control both the structure and physical properties of materials. In this work, kink band defects are systematically introduced into a lamellar poly(styrene-b-ethylene propylene) diblock copolymer by applying various rates and total strains of steady shear. However, kink bands are only produced when the shear strain exceeds a critical value. The mere existence of kink bands implies the presence of a preferential slip plane parallel to the lamellae, which we estimate exists within the polystyrene microdomains. Furthermore, our results regarding the dependence of kink band geometry on shear rate and strain suggest that these defects are formed by the rotation of lamellae. Based on a rotation mechanism, the characteristic size of the kink bands and their spatial distribution, it appears that preexisting defects initiate kink bands. Insights gained from steady-shear-induced kink bands are extended to oscillatory shear alignment of this high molecular weight di...
Coherent Pattern Prediction in Swarms of Delay-Coupled Agents

We consider a general swarm model of self-propelling agents interacting through a pairwise potential in the presence of noise and communication time delay. Previous work has shown that a communication time delay in the swarm induces a pattern bifurcation that depends on the size of the coupling amplitude. We extend these results by completely unfolding the bifurcation structure of the mean field approximation. Our analysis reveals a direct correspondence between the different dynamical behaviors found in different regions of the coupling-time delay plane with the different classes of simulated coherent swarm patterns. We derive the spatiotemporal scales of the swarm structures, as well as demonstrate how the complicated interplay of coupling strength, time delay, noise intensity, and choice of initial conditions can affect the swarm. In particular, our studies show that for sufficiently large values of the coupling strength and/or the time delay, there is a noise intensity threshold that forces a transition of the swarm from a misaligned state into an aligned state. We show that this alignment transition exhibits hysteresis when the noise intensity is taken to be time dependent.
Stochastic regulation of queues in data networks

Abstract A new class of routing policies for the regulation of queue lengths at all nodes throughout a data network in the presence of congestion caused by heavy input traffic is developed. Regulation is achieved via a feedback algorithm which minimizes, over each successive control interval, the mean-square queueing error where the latter is the difference between the actual queueing vector and its desired nominal value. Implementation of the algorithm requires knowledge of the mean and covariance of the input traffic and of the queue length measurement error stochastic processes. In the case of the former process, on-line measurements can be used to calculate the required statistical parameters. For the latter process, a priori knowledge that reflects the uncertainty in measuring and transmitting queue lengths throughout the network is needed.
Assessing merged DRAM/logic technology

Abstract This paper describes the impact of DRAM process on the logic circuit performance of Memory/Logic Merged Integrated Circuit and the alternative circuit design technology to offset the performance penalty. Extensive circuit and routing simulations have been performed to study the logic circuit performance degradation when the merged chip is implemented on DRAM process. Three logic processes ( 0.5, 0.6 and 0.8 μm) and two corresponding contemporary DRAM (64 and 256 Mb) processes have been selected for the study knowing that the performance difference between the logic and DRAM processes can be extrapolated for the advanced processes. The simulation results show that the logic circuit performance is degraded by about 22% on DRAM process including the increased interconnect delay due to less interconnect layers available in the DRAM process. The silicon area is increased up to 80% depending on the number of net and components when implementing a logic circuit in a DRAM process. Simulation results show that the performance penalty can be well offset if the same circuit used in the simulation is implemented using dynamic circuit techniques.
XUV free-electron laser-based projection lithography systems

Free-electron laser sources, driven by ri-linear accelerators, have the potential to operate in the extreme ultraviolet (XUV) spectral range with more thansutficient average power for high-volume projection lithography. For XUV wavelengths from 100 nm to 4 nm, such sources will enable the resolution limit of optical projection lithography to be extended from 0.25 pm to 0.05 im and with an adequate total depth of focus (1 to 2 jtm). Recent developments of a photoinjector of very bright electron beams, high-precision magnetic undulators, and ring-resonator cavities raise our confidence that FEL operation below I 00 nm is ready for prototype demonstration. We address the motivation for an XUV FEL source for commercial microcircuit production and its integration into a lithographic system, including reflecting reduction masks, reflecting XUV projection optics and alignment systems, and surface-imaging photoresists.
The puzzle of high temperature superconductivity in layered iron pnictides and chalcogenides

The response of the worldwide scientific community to the discovery in 2008 of superconductivity at T c = 26 K in the Fe-based compound LaFeAsO1−x F x has been very enthusiastic. In short order, ot...
Comparison of simultaneous Doppler- and catheter-derived right ventricular dP/dt in hypoplastic left heart syndrome.

Abstract Doppler estimation of RV dP dt correlates well with micromanometer catheter-measured values in children with hypoplastic left heart syndrome. Doppler estimation of RV dP dt is a method of quantifying RV systolic function independent of geometric assumptions, and may be a valuable method for longitudinal analysis of RV function.
The Polarization of American Politics

Elected officials in the United States appear to represent relatively extreme support coalitions rather than the interests of middle-of-the-road voters. This contention is supported by analysis of variance of liberal-conservative positions in the United States Senate from 1959 to 1980. Within both the Democratic and the Republican parties, there is considerable variation in liberal-conservative positions, but two senators from the same state and party tend to be very similar. In contrast, senators from the same state but from different parties are highly dissimilar, suggesting that each party represents an extreme support coalition in the state. Moreover, the distribution of senators is now consistent with the hypothesis that, in the long run, both parties have an equal chance of winning any seat in the Senate. This result suggests that there is now competition between equally balanced but extreme support coalitions throughout most of the United States.
CALCULATION OF HEAT TRANSFER IN A RADIALLY ROTATING COOLANT PASSAGE

The three-dimensional flow field and heat transfer in a radially rotating coolant passage are studied numerically. The passage chosen has a square cross section with smooth isothermal walls of finite length. The axis of rotation is normal to the flow direction with the flow radially outward. The effects of Coriolis forces, centrifugal buoyancy, and fluid Reynolds number on the flow and heat transfer have all been considered. The analysis has been performed by using a fully elliptic, three-dimensional, body-fitted computational fluid dynamics code based on pressure correction techniques. The numerical technique employs a multigrid iterative solution procedure and the standard κ − e turbulence model for both the hydrodynamics and heat transfer. The effect of rotation is included by considering the governing equations of motion in a relative frame of reference that moves with the passage. The consequence of rotation is to bring higher velocity fluid from the core to the trailing surface, thereby increasing b...
The performance of small mines in Namibia and the region

Both large and medium‐sized mines in southern Africa are contributing less to the economy owing to rising production costs and poor demand for minerals. Politicians argue that small mines can make an important economic contribution. But this analysis shows that small mines face real constraints and that there are clear prospects only in semiprecious and dimension stones. Specific research is needed to help small mines overcome their limitations.
Use Patents, Carve-Outs, and Incentives — A New Battle in the Drug-Patent Wars

The Hatch–Waxman Act aims to strike a balance between the innovation incentives provided by patents and the greater access provided by generic drugs. Now the tactical landscape in the drug-patent wars has shifted again, with a recently decided Supreme Court case.
Toward a structural textural analyzer based on statistical methods

Abstract This paper reports investigations aimed at developing a feature set for the Spatial Gray Level Dependence Method (SGLDM) which measures visually perceivable qualities of textures. In particular it will be shown that the inertia measure commonly used with the SGLDM can be used to characterize the placement rules and the unit pattern of periodic textures. In this way one may formulate a structural approach to texture analysis based on the statistical SGLDM. To mathematically verify that the features used with the SGLDM can be used to characterize the unit pattern and placement rules of a periodic texture, a mathematical tiling theory model is proposed. This model allows one to develop the mathematical machinery necessary to prove the result. In a companion paper other features which measure visually perceivable qualities of patterns will be developed. The reason for concentrating on the SGLDM for developing such a feature set is predicated on perceptual psychology experiments and comparison studies of various texture algorithms. All of these studies indicate that second-order probabilities of the type measured by the spatial gray level dependence matrices are important in human texture discrimination and that these matrices contain more important texture-context information than the intermediate matrices of other statistical texture analysis algorithms.
TIMER: Tensor Image Morphing for Elastic Registration

We propose a novel diffusion tensor imaging (DTI) registration algorithm, called Tensor Image Morphing for Elastic Registration (TIMER), which leverages the hierarchical guidance of regional distributions and local boundaries, both extracted directly from the tensors. Currently available DTI registration methods generally extract tensor scalar features from each tensor to construct scalar maps. Subsequently, regional integration and other operations such as edge detection are performed to extract more features to guide the registration. However, there are two major limitations with these approaches. First, the computed regional features might not reflect the actual regional tensor distributions. Second, by the same token, gradient maps calculated from the tensor-derived scalar feature maps might not represent the actual tissue tensor boundaries. To overcome these limitations, we propose a new approach which extracts regional and edge information directly from a tensor neighborhood. Regional tensor distribution information, such as mean and variance, is computed in a multiscale fashion directly from the tensors by taking into account the voxel neighborhood of different sizes, and hence capturing tensor information at different scales, which in turn can be employed to hierarchically guide the registration. Such multiscale scheme can help alleviate the problem of local minimum and is also more robust to noise since one can better determine the statistical properties of each voxel by taking into account the properties of its surrounding. Also incorporated in our method is edge information extracted directly from the tensors, which is crucial to facilitate registration of tissue boundaries. Experiments involving real subjects, simulated subjects, fiber tracking, and atrophy detection indicate that TIMER performs better than the other methods (Yang et al., 2008; Zhang et al., 2006).
Stability of atomic clocks based on entangled atoms.

We analyze the effect of realistic noise sources for an atomic clock consisting of a local oscillator that is actively locked to a spin-squeezed (entangled) ensemble of $N$ atoms. We show that the use of entangled states can lead to an improvement of the long-term stability of the clock when the measurement is limited by decoherence associated with instability of the local oscillator combined with fluctuations in the atomic ensemble's Bloch vector. Atomic states with a moderate degree of entanglement yield the maximal clock stability, resulting in an improvement that scales as ${N}^{1/6}$ compared to the atomic shot noise level.
Stable cointegrating regressions: Fully-modified estimates for inflation and employment cost indices

This paper investigates the stability of relationships between inflation and changes in employer cost for labor using tests based on the null hypothesis of no cointegration (Gregory and Hansen (1996a)) as well as tests based on the null hypothesis of cointegration (Hansen (1992)). In addition to specifications which include wages or unit labor cost, employment cost indices for compensation and wages are used to eliminate composition bias over the business cycle. Empirical results support stability and fully-modified estimates are obtained using the semiparametric approach of Phillips (1995). In contrast to studies which have found only one-way causality, this paper presents empirical evidence of feedback between inflation and employer cost for labor, consistent with an expectations-adjusted Phillips's Curve.
Accountability in a Postdesegregation Era: The Continuing Significance of Racial Segregation in Florida’s Schools

In the wake of both the end of court-ordered school desegregation and the growing popularity of accountability as a mechanism to maximize student achievement, the authors explore the association between racial segregation and the percentage of students passing high-stakes tests in Florida’s schools. Results suggest that segregation matters in predicting school-level performance on the Florida Comprehensive Assessment Test after control for other known and purported predictors of standardized test performance. Also, these results suggest that neither recent efforts by the state of Florida to equalize the funding of education nor current efforts involving high-stakes testing will close the Black-White achievement gap without consideration of the racial distribution of students across schools.
Income Security for Workers: A Stressed Support System in Need of Innovation

The current mix of public and private programs to support workers after they experience disability onset provides benefits to millions of workers and former workers. Yet, despite the large and growing costs of these programs, the inflation-adjusted household incomes of workers with disabilities have been falling for more than two decades, both absolutely and, especially, relative to the incomes of those without disabilities. The aging of the baby boom generation is likely to make matters worse, and the government’s fiscal circumstance will make it increasingly difficult to sustain existing public programs. Current public policy initiatives might eventually improve the disability support system, but they are not likely to ward off the adverse consequences of the pending crisis. Policy changes that leverage existing private sector practices and capabilities might achieve greater success but have received little attention and are far from proven.
Constraints on the Long-Range Properties of Gravity from Weak Gravitational Lensing

Weak gravitational lensing provides a means of testing the long-range properties of gravity. Current measurements are consistent with standard Newtonian gravity and inconsistent with substantial modifications on megaparsec scales. The data allow long-range gravity to deviate from a 1/r potential only on scales where standard cosmology would use normal gravity, but be dominated by dark matter. Thus, abnormal gravity theories must introduce two fine-tuning scales (an inner scale to explain flat rotation curves and an outer scale to force a return to Newtonian gravity on large scales), and these scales must coincidentally match the scales produced by dark matter theory after evolving the universe for 10 billion years, starting from initial conditions that are exquisitely determined from the cosmic microwave background.
Loose packings of frictional spheres

We have produced loose packings of cohesionless, frictional spheres by sequential deposition of highly-spherical, monodisperse particles through a fluid. By varying the properties of the fluid and the particles, we have identified the Stokes number (St)—rather than the buoyancy of the particles in the fluid—as the parameter controlling the approach to the loose packing limit. The loose packing limit is attained at a threshold value of St at which the kinetic energy of a particle impinging on the packing is fully dissipated by the fluid. Thus, for cohesionless particles, the dynamics of the deposition process, rather than the stability of the static packing, defines the random loose packing limit. We have made direct measurements of the interparticle friction in the fluid, and present an experimental measurement of the loose packing volume fraction, ϕRLP, as a function of the friction coefficient μs.
The asymptotic density of finite-order elements in virtually nilpotent groups

Abstract Let Γ be a finitely generated group with a given word metric. The asymptotic density of elements in Γ that have a particular property P is the limit, as r → ∞ , of the proportion of elements in the ball of radius r which have the property P. We obtain a formula to compute the asymptotic density of finite-order elements in any virtually nilpotent group. Further, we show that the spectrum of numbers that occur as such asymptotic densities consists of exactly the rational numbers in [ 0 , 1 ) .
Role of hyperon negative energy sea in nuclear matter

Abstract We have examined the contribution of the filled negative energy sea of hyperons to the energy/particle in nuclear matter at the one and two loop levels. While this has the potential to be significant, we find a strong cancellation between the one and two loop contributions for our chosen parameters so that hyperon effects can be justifiably neglected.
Prior-independent auctions for risk-averse agents

We study simple and approximately optimal auctions for agents with a particular form of risk-averse preferences. We show that, for symmetric agents, the optimal revenue (given a prior distribution over the agent preferences) can be approximated by the first-price auction (which is prior independent), and, for asymmetric agents, the optimal revenue can be approximated by an auction with simple form. These results are based on two technical methods. The first is for upper-bounding the revenue from a risk-averse agent. The second gives a payment identity for mechanisms with pay-your-bid semantics.
Three-Dimensional 2-Framed TQFTs and Surgery

The notion of 2-framed three-manifolds is defined. The category of 2-framed cobordisms is described, and used to define a 2-framed three-dimensional TQFT. Using skeletonization and special features of this category, a small set of data and relations is given that suffice to construct a 2-framed three-dimensional TQFT. These data and relations are expressed in the language of surgery.
Flavor-octet dibaryons in the quark model

The possibility of flavor-SU(3)-octet dibaryon resonances is studied in the quark model. Because the color-magnetic gluon-exchange interaction is attractive for the flavor octets as well as the singlet, bound and/or resonance states are expected. The importance of two-baryon channel couplings and quark antisymmetrization is stressed for low-lying bound/resonance states. The dibaryon spectrum is studied by applying the quark cluster model to the J${=1}^{+}$ and ${2}^{+}$ six-quark states. Several J${=2}^{+}$ dibaryon resonances are predicted.
Experimental and phenomenological status of neutrino anomalies

The current status of neutrino anomalies is summarized; the KamLAND experiment is described and the recent results of KamLAND presented.
Bayes factor consistency for unbalanced ANOVA models

In practical situations, most experimental designs often yield unbalanced data which have different numbers of observations per unit because of cost constraints, missing data, etc. In this paper, we consider the Bayesian approach to hypothesis testing or model selection under the one-way unbalanced fixed-effects analysis-of-variance (ANOVA) model. We adopt Zellner's g-prior with the beta-prime distribution for g, which results in an explicit closed-form expression of the Bayes factor without integral representation. Furthermore, we investigate the model selection consistency of the Bayes factor under three different asymptotic scenarios: either the number of units goes to infinity, the number of observations per unit goes to infinity, or both go to infinity. The results presented extend some existing ones of the Bayes factor for the balanced ANOVA models in the literature.
Errors in variables in panel data

Abstract Panel data based studies in econometrics use the analysis of covariance approach to control for various ‘individual effects’ by estimating coefficients from the ‘within’ dimension of the data. Often, however, the results are unsatisfactory, with ‘too low’ and insignificant coefficients. Errors of measurement in the independent variables whose relative importance gets magnified in the within dimension are then blamed for this outcome. Errors-in-variables models have not been used widely, in part because they seem to require extraneous information to be identified. We show how a variety of errors-in-variables models may be identifiable and estimable in panel data without the use of external instruments and apply it to a relatively simple but not uninteresting case: the estimation of ‘labor demand’ relationships, also known as the ‘short-run increasing returns to scale’ puzzle.
Reward Dominance in Tax‐Reporting Experiments: The Role of Context

During the past decade, the experimental economics method increasingly has been used to study the impact of tax policy on taxpayer behavior. Experimental economics in taxation typically tests tax applications of expected utility and psychological theory by creating a real microeconomy in the laboratory. A key requirement is strict control over the parameters of the experimental setting and subject preferences. One generally accepted procedure to achieve experimental control is to avoid references to real‐world phenomena in instructions to subjects. The reasoning underlying this procedure is that if subjects associate the experiment with real‐world phenomena, they may make decisions based on values associated with the real‐world context instead of the rewards and penalties of the microeconomy. Despite this, several recent tax‐reporting experiments that otherwise conform to the experimental economics method have used explicit tax terminology. In discussing the results of these experiments, the authors and c...
The triple junction hull: Tools for grain boundary network design

Abstract Grain boundary engineering (GBE) studies have demonstrated significant materials properties enhancements by modifying the populations and connectivity of different types of grain boundaries within the grain boundary network. In order to facilitate rigorous design and optimization of grain boundary networks, we develop theoretical tools that are based upon a spectral representation of grain boundary network statistics. We identify the connection between a local length scale, embodied by triple junctions, and a global length scale, associated with the grain boundary network configuration as a whole. We define the local state space for triple junctions, A ( 3 ) , and enumerate its symmetries. We further define the design space for grain boundary networks, M H ( 3 ) , characterize its important geometric properties, and discuss how its convexity permits grain boundary network design. We also investigate the extent to which the control of texture alone allows one to probe the full design space.
Composition, Structure, Stress, and Coercivity of Electrodeposited Soft Magnetic CoNiFe Films: Thickness and Substrate Dependence

The properties of soft magnetic CoNiFe films electrodeposited in the presence of saccharin and sodium lauryl sulfate additives were studied in terms of their thickness and substrate dependence. Auger depth profile analysis of the elemental composition in CoNife films electrodeposited over different substrates (Pd 00 Ni 10. 1.0 T NiFe.Cu) demonstrate that the average composition at the substrate interface and bulk deposited films remains constant. X-ray diffraction (XRD) measurements reveal the existence of mixed fcc + bcc phase with larger amounts of bcc crystallites near the substrate side of the films, i.e.,at the lower thickness. XRD and transmission electron microscopy measurements revealed a larger grain size at the CoNiFe/substrate interface. The measured average stress is both substrate- and thickness-dependent. The easy-axis coercivity, H c , follows the Neel's relation H c = ct n (t is the thickness and c is a constant). It was found that the value of the exponent n is substrate dependent. Mechanisms related to the coercivity of CoNiFe films deposited ovar different substrates (1.0 T NiFe, Cu, Pd 90 Ni 10 , high magnetic moment CoNiFe) are discussed in terms of material properties of these magnetic films.
Cosmic Acceleration as the Solution to the Cosmological Constant Problem

In this paper we provide both a diagnosis and resolution of the cosmological constant problem, one in which a large (as opposed to a small) cosmological constant Λ can be made compatible with observation. We trace the origin of the cosmological constant problem to the assumption that the local gravitational Newton constant G (as measured in a Cavendish experiment) sets the scale for global cosmology. Then we show that once this assumption is relaxed, the very same cosmic acceleration that has served to make the cosmological constant problem so very severe can instead serve to provide us with its potential resolution. In particular, we present an alternate cosmology, one based on conformal gravity, a theory whose effective cosmological Geff not only differs from the Cavendish one by being altogether smaller than it but, by even being explicitly negative, naturally leads to cosmological repulsion. We show in the conformal theory that once given only that the sign of Λ is specifically the negative one associated with spontaneous scale symmetry breaking, then that alone, no matter how big Λ might actually be in magnitude, is not only sufficient to make the actually measurable contribution 8πGeffΛ/3cH2(t0) of Λ to current era cosmology naturally be of order 1 today, but to even do so in a way that is fully compatible with the recent high-z supernova cosmology data. Thus, to solve the cosmological constant problem, we do not need to change or quench the energy content of the universe, but rather we only need to change its effect on cosmic evolution.
Gravitational backreaction of matter inhomogeneities

The non-linearity of Einstein's equations makes it possible for small scale matter inhomogeneities to affect the universe at cosmological distances. We study the size of such effects using a simple heuristic model that captures the most important backreaction effect due to non-relativistic matter, as well as several exact solutions describing inhomogeneous and anisotropic expanding universes. We find that the effects are O(H2l2/c2) or smaller, where H is the Hubble parameter and l the typical size scale of inhomogeneities. For virialized structures this is of order v2/c2, where v is the characteristic peculiar velocity.
Structure and Physical Properties of La3.4Ca0.6V5Si4O22: A Novel Mixed-Valent Vanadium(III/IV) Oxosilicate

The authors studied the crystal structure and physical properties of La{sub 3.4}Ca{sub 0.6}V{sub 5}Si{sub 4}O{sub 22}. The compound crystallizes in the monoclinic system, space group C2/m (No. 12). The magnetic susceptibility of this compound follows Curie-Weiss behavior. Measurements of the electric conductivity indicate that this compound is an insulator.
Neutron stars and white dwarfs in galactic halos

The possibility that galactic halos are composed of stellar remnants such as neutron stars and white dwarfs is discussed. On the basis of a simple model for the evolution of galactic halos, researchers follow the history of halo matter, luminosity, and metal and helium abundances. They assume conventional yields for helium and the heavier elements. By comparing with the observational constraints, which may be considered as fairly conservative, it is found that, for an exponentially decreasing star formation rate (SFR) with e-folding time tau, only values between 6 x 10(8) less than similar to tau less than similar to 2 x 10(9) years are allowed together with a very limited range of masses for the initial mass function (IMF). Star formation is allowed for 2 solar mass less than similar to m less than similar to 8 solar mass if tau = 2 x 10(9) years, and for 4 solar mass less than similar to m less than similar to 6 solar mass if tau = 10(9) years. For tau = 6 x 10(8) years, the lower and upper mass limits merge to similar to 5 solar mass. Researchers conclude that, even though the possibility of neutron stars as halo matter may be ruled out, that of white dwarfs may still be a viable hypothesis, though with very stringent constraints on allowed parameters, that merits further consideration.
Facile conversion of epoxides to β-hydroxy nitriles under anhydrous conditions with lithium cyanide

Abstract Functionalized epoxides are easily and efficiently converted to β-hydroxy nitriles in good yield with high regio- and stereoselectivity upon treatment with lithium cyanide in refluxing anhydrous THF. The conditions described permit a one-pot conversion of epoxide to 1,3-amino alcohol via hydride reduction of the nitrile.
A Bayesian approach to snow water equivalent reconstruction

[1] Snow water equivalent (SWE) reconstruction methods have previously been used to characterize seasonal SWE accumulation using mass and energy balance models and time series of remotely sensed snow-covered area (SCA). Recognizing that the spatial signature of the seasonal SWE accumulation is an integration of a series of snowfall events, we have formulated a Bayesian SWE reconstruction that combines time series of remote sensing estimates of SCA with a land surface model to estimate storm-specific snowfall distribution with a retrospective data assimilation scheme. The analysis is identical in form to the ensemble Kalman filter or ensemble Kalman smoother. A snow depletion curve is used to relate SCA and SWE. We perform a series of synthetic tests to assess how much information concerning snowfall accumulation patterns can be extracted from a time series of SCA measurements taken during the ablation season. The posterior estimate of SWE calculated via our method effectively recovers the true SWE: the mean and standard deviation of the SWE estimate error improve by 86% and by 78%, respectively, over the prior for pixels with vegetation fraction less than 90%. The sensitivity of the method to climatic and physiographic variables and input errors is investigated. The technique shows promise for future work in characterizing spatial patterns of snowfall over mountainous regions.
Large-scale structure of time evolving citation networks

In this paper we examine a number of methods for probing and understanding the large-scale structure of networks that evolve over time. We focus in particular on citation networks, networks of references between documents such as papers, patents, or court cases. We describe three different methods of analysis, one based on an expectation-maximization algorithm, one based on modularity optimization, and one based on eigenvector centrality. Using the network of citations between opinions of the United States Supreme Court as an example, we demonstrate how each of these methods can reveal significant structural divisions in the network and how, ultimately, the combination of all three can help us develop a coherent overall picture of the network's shape.
AlGaN-Based Photodetectors Grown by Gas Source Molecular Beam Epitaxy with Ammonia

AlGaN p-n junctions were used to fabricate photodetectors operating between 280 and 380 nm. Detector structures were grown on silicon and sapphire substrates by gas source molecular beam epitaxy with ammonia. Layers of n-Al x Ga 1-x N (0 ≤ x AlN < 0.08) were grown at a temperature of 800 °C on a buffer layer of AIN. The p-type layers of Al x Ga 1-x N (0 ≤ x AlN ≤ 0.08) were co-doped with Mg and oxygen. Hole concentrations as high as 2 x 10 18 cm -3 were measured by capacitance voltage profiling. In the p-Al 0.08 Ga 0.92 N layer we measured acceptor activation energy of 195 ± 10 meV. In a comparable layer of p-GaN, also co-doped with Mg and O, the acceptor activation energy was 130-165 meV. Low activation energies are attributed to successful co-doping. In mesa etched diodes we measured zero-bias leakage currents as low as 6 x 10 -13 A cm -2 .
A High Performance, Anode-Supported Solid Oxide Fuel Cell Operating on Direct Alcohol

Anode-supported solid oxide fuel cells with a thin film of yttria-stabilized zirconia (YSZ) as the electrolyte were fabricated. The cells were operated directly on pure methanol and on an equivolume mixture of ethanol and water over a range of temperatures. Power density achieved with methanol was between 0.6 W/cm 2 at 650°C and 1.3 W/cm 2 at 800°C, and with ethanol + water between 0.3 W/cm 2 at 650°C and 0.8 W/cm 2 at 800°C. Results were compared with tests on humidified hydrogen as a fuel. No carbon deposition on the Ni-YSZ anode was observed with either methanol or an equivolume solution of ethanol and water as fuels. Differences in performance with different fuels were attributed to differences in anode polarization.
Reactivity of N-(1,2,4-Triazolyl)-Substituted 1,2,3-Triazoles

Synthetically useful rhodium(II) carbenes were obtained from N-(1,2,4-triazolyl)-substituted 1,2,3-triazoles and Rh(II) carboxylates. The electron-withdrawing 1,2,4-triazolyl group reveals the heretofore unknown reactivity of nonsulfonyl 1,2,3-triazoles, which exhibit the reactivity of diazo compounds. The resulting carbenes provide ready asymmetric access to secondary homoaminocyclopropanes (80–95% ee, dr >20:1) via reactions with olefins and also engage in efficient transannulation reactions with nitriles.
The Role of Giant Planets in Terrestrial Planet Formation

We present the results of simulations of the late stages of terrestrial planet formation under the gravitational influence of six different outer giant planetary systems with a wide range of dynamical characteristics. Our goal is to examine the role that the giant planets play in determining the number, mass, and orbital characteristics of the resulting terrestrial planets and their general potential for habitability. Each of the giant-planet systems affects the embryos in its own unique way. However, we find that the most profound effects are secular in nature. We also discovered that dynamical excitation of the embryos by the giant planets in one region can be transferred into another on short timescales via what we call secular conduction. Despite large differences in the behaviors of our systems, we have found general trends that seem to apply. The number, mass, and location of the terrestrial planets are directly related to the amount of dynamical excitation experienced by the planetary embryos near 1 AU. In general, if the embryos' eccentricities are large, each is crossing the orbits of a larger fraction of its cohorts, which leads to a lesser number of more massive planets. In addition, embryos tend to collide with objects near their periastron. Thus, in systems where the embryos' eccentricities are large, planets tend to form close to the central star.
Characterization of UPd3 stabilized in the DO19 structure

Abstract A new DO19 compound U(Pd 0.8 Au 0.2 ) 3 was prepared. Replacing Pt in the DO19 alloy UPt 3 by Pd normally leads to a transition to the DO24 structure. This is prevented when 20% Pd is replaced by Au. Previous experiments have shown that spin fluctuations in UPt 3 are suppressed and the large specific heat γ value ( C / T (1.2 K) = 420 mJ mol −1 K −2 ) is decreased by half when alloying with 20% Pd. For UPd 3 stabilized in the DO19 structure with 20% Au, it is found that the electronic contribution to the specific heat decreases further, with a γ value of only 40 mJ (U-mol K 2 ) −1 .
CONTINUUM AND EMISSION-LINE STRENGTH RELATIONS FOR A LARGE ACTIVE GALACTIC NUCLEI SAMPLE

We report on the analysis of a large sample of 744 type 1 active galactic nuclei, including quasars and Seyfert 1 galaxies across the redshift from 0 z 5 and spanning nearly 6 orders of magnitude in continuum luminosity. We discuss correlations of continuum and emission-line properties in the rest-frame ultraviolet and optical spectral ranges. The well-established Baldwin effect is detected for almost all emission lines from O VI ?1034 to [O III] ?5007. Their equivalent widths are significantly anticorrelated with the continuum strength, while they are nearly independent of redshift. This is the well-known Baldwin effect. Its slope ?, measured as log W? ? log ?L?(1450 ?), shows a tendency to become steeper toward higher luminosity. The slope of the Baldwin effect also increases with the ionization energy needed to create the individual lines. In contrast to this general trend, the N V ?1240 equivalent width is nearly independent of continuum luminosity and remains nearly constant. The overall line behaviors are consistent with softer UV continuum shapes and perhaps increasing gas metallicity in more luminous active galactic nuclei.
A MAP equalizer for the optical communications channel

A maximum a posteriori (MAP) equalizer is presented for optical fiber communication systems. Assuming that the span of the intersymbol interference (ISI) does not extend beyond neighboring bits-typically the case for the distortion introduced by polarization-mode dispersion (PMD)-we derive the conditional probability density function (pdf) in the electrical domain in the presence of PMD and amplified spontaneous emission (ASE)-dominated noise. Simulation results with an accurate receiver model and all-order PMD show the success of the MAP equalizer in reducing the bit error rate (BER) degradation due to PMD.
Genetic and Evolutionary Correlates of Fine-Scale Recombination Rate Variation in Drosophila persimilis

Recombination is fundamental to meiosis in many species and generates variation on which natural selection can act, yet fine-scale linkage maps are cumbersome to construct. We generated a fine-scale map of recombination rates across two major chromosomes in Drosophila persimilis using 181 SNP markers spanning two of five major chromosome arms. Using this map, we report significant fine-scale heterogeneity of local recombination rates. However, we also observed “recombinational neighborhoods,” where adjacent intervals had similar recombination rates after excluding regions near the centromere and telomere. We further found significant positive associations of fine-scale recombination rate with repetitive element abundance and a 13-bp sequence motif known to associate with human recombination rates. We noted strong crossover interference extending 5–7 Mb from the initial crossover event. Further, we observed that fine-scale recombination rates in D. persimilis are strongly correlated with those obtained from a comparable study of its sister species, D. pseudoobscura. We documented a significant relationship between recombination rates and intron nucleotide sequence diversity within species, but no relationship between recombination rate and intron divergence between species. These results are consistent with selection models (hitchhiking and background selection) rather than mutagenic recombination models for explaining the relationship of recombination with nucleotide diversity within species. Finally, we found significant correlations between recombination rate and GC content, supporting both GC-biased gene conversion (BGC) models and selection-driven codon bias models. Overall, this genome-enabled map of fine-scale recombination rates allowed us to confirm findings of broader-scale studies and identify multiple novel features that merit further investigation.
Stabilization of Nonlinear Systems with Semi-Quadratic Cost

The paper addresses the stabilization of nonlinear systems with semi-quadratic cost: quadratic with respect to controls and nonlinear for state variables. Paper presents the effective new feedback synthesis procedure. The novel feedback design procedure is based on the ideas borrowed from nonlinear optics and the theory of semi-classical asymptotics developed in quantum mechanics.
Stardust Entry Reconstruction

An overview of the reconstruction analyses performed for the Stardust capsule entry is described. The results indicate that the actual entry was very close to the pre-entry predictions. The capsule landed 8.1 km north-northwest of the desired target at Utah Test and Training Range. Analyses of infrared video footage and radar range data (obtained from tracking stations) during the descent show that drogue parachute deployment was 4.8 s later than the pre-entry prediction, while main parachute deployment was 19.3 s earlier than the pre-set timer indicating that main deployment was actually triggered by the backup baroswitch. Reconstruction of a best estimated trajectory revealed that the aerodynamic drag experienced by the capsule during hypersonic flight was within 1% of pre-entry predications. Observations of the heatshield support the pre-entry estimates of small hypersonic angles of attack, since there was very little, if any, charring of the shoulder region or the aftbody. Through this investigation, an overall assertion can be made that all the data gathered from the Stardust capsule entry were consistent with flight performance close to nominal pre-entry predictions. Consequently, the design principles and methodologies utilized for the flight dynamics, aerodynamics, and aerothermodynamics analyses have been corroborated.
Charge-coupled device and charge-injection device imaging

A brief review is given of the advances in solid-state imaging during the last ten years. The issues of surface channel versus buried channel, aliasing versus prefiltering, frame transfer (FT) versus interline transfer (IT) versus charge-injection device (CID), and direct view versus EBIC imaging are discussed. Time-delay-and-integration (TDI) and infrared imaging are discussed. Finally applications are considered.
Excited state acid-base chemistry a new quenching mechanism

Abstract Most photochemical reactions degrade a metal complex, but recent experiments in this laboratory reveal a series of unusual photochemical reactions that increase the metal content of the complex. A 450 nm excitation of bis(2,2′-bipyridine)(2,3-bis(2-pyridyl)pyrazine)ruthenium(II), Ru(bpy) 2 dpp 2+ , complexes in the presence of PtCl 6 2− , PdCl 6 2− and RhCl 6 3− results in quantitative formation of the corresponding bimetallic [Ru(bpy) 2 (dpp)MCl 4 ] 2+ . The excited state energies and thermal redox potentials of the chlorides and the specificity of the reaction suggest that formation of the bimetallic is not the consequence of energy transfer or electron transfer quenching. Instead, we propose that these reactions are the result of an excited state acid-base chemistry that manifests itself as changes in coordination and nucleophilicity. The emissive MLCT state in Ru(bpy) 2 (dpp) 2+ is localized on dpp, and H + quenching indicates that population of the emissive MLCT state increases the basicity of at least one of the peripheral nitrogens by at least four orders of magnitude relative to that in the ground state. Population of the MLCT state (bpy) 2 Ru(CN) 2 , on the other hand, shifts charge density to the bpy ligand thereby decreasing the basicity of the cyanide ligand by ca. four orders of magnitude. The pH dependence of the quantum yield of decomposition of trans -[(bpy) 2 Ru(CN)(μ-CN)Rh(NH 3 ) 4 Br] 2+ suggests that this immense change in basicity leads to a dissociative excited state. In complexes that exhibit excited state acid-base properties, the data presented here suggest that quenching is not necessarily limited to electron or energy transfer, but also occurs by an excited state acid-base chemistry that leads to changes in coordination and/or nucleophilicity.
Solitons and instantons with (out) supersymmetry

Abstract We give model-independent arguments, valid in nearly any number of spacetime dimensions, that topological solitons and instantons satisfy Bogomol'nyi-type bounds and, when these bounds are saturated, satisfy self-duality equations. In the supersymmetric case, we also show that, in spacetime dimensions greater than two, theories with topological charges necessarily exhibit extended supersymmerry, in which the topological charge appears as the central charge. The significance of our arguments lies in their generality. In the supersymmetric case, we obtain insight into the contrast observed between topological charges in 1+1 and higher dimensional models. The centerpiece of our method is to require that the supersymmetric extension of a generic (non-supersymmetric) field theory be self-consistent.
Timed testing of concurrent systems

We are concerned with timing considerations for concurrent systems where the time needed by the individual actions is not known beforehand; it has long been suspected that partial order semantics is useful here. We develop a suitable testing scenario to study this idea. With some view of timed behaviour, we can confirm that interval semiword semantics, a special partial order semantics, is indeed useful. With another view, our testing scenario leads to timed-refusal-trace semantics, where no relation to partial order semantics is obvious.
Ohmic contacts to GaAs

Abstract The present capability of obtaining ohmic contacts to GaAs over a range of doping levels is reviewed. Possible models of transport across the metal-semiconductor interface are discussed and contact techniques are described. The widely used AuGe alloyed contact is seen to have a spatially inhomogeneous interface which appears to control its contact resistance. The most satisfactory process at this time is to alloy into a previously fabricated heavily doped layer.