cssi/SciSciGPT-SciSciNet huggingface dataset:
Extended Families and Child Well-being

Studies of household behavior have established the distribution of resources among household members predicts spending and savings patterns. However, there is a paucity of evidence on the relationship between the well-being of individual family members and the distribution of resources within an extended family including non co-resident family members. Given the central role the family plays in many models of economic behavior, this is an important gap in the literature. Using rich longitudinal survey data from the Indonesia Family Life Survey (IFLS), evidence is presented on the relationship between three measures of health- and education-related human capital of children and the distribution of resources among extended family members. IFLS is ideally suited for this research since the survey collects detailed information about income and wealth from both coresident and non co-resident family members. The empirical model is founded on a natural extension of the collective model of household decision-making (Chiappori, 1988, 1992) to the extended family. The model is particularly appealing in this context because it places few restrictions on preferences of individual family members and does not specify a specific bargaining mechanism that underlies negotiations. The collective model yields empirical tests of whether the behavior of family members is (Pareto) efficient. A special case of the model allows all family members to be completely altruistic which is observationally equivalent to a unitary model of family behavior. That special case is rejected by the data. However, the restrictions of the efficient model are not rejected, indicating that non co-resident family members are able to co-ordinate allocation decisions with respect to child human capital investments in such a way as to make no family member better off without another member being worse off.
Robustness of discrete-time adaptive controllers: an input-output approach

A general input-output approach that can be used for the design and analysis of robust discrete-time adaptive control schemes is presented. In particular, a model reference adaptive controller is considered. The design approach involves the use of the certainty equivalence principle to combine a robust control structure with a robust adaptive law. Using exponentially weighted I/sub 2/ norms and exploiting the properties of the adaptive law and the control structure, robust stability is established for the closed-loop adaptive control scheme. >
WATER VAPOR AND THE DYNAMICS OF CLIMATE CHANGES

[1] Water vapor is not only Earth's dominant greenhouse gas. Through the release of latent heat when it condenses, it also plays an active role in dynamic processes that shape the global circulation of the atmosphere and thus climate. Here we present an overview of how latent heat release affects atmosphere dynamics in a broad range of climates, ranging from extremely cold to extremely warm. Contrary to widely held beliefs, atmospheric circulation statistics can change nonmonotonically with global-mean surface temperature, in part because of dynamic effects of water vapor. For example, the strengths of the tropical Hadley circulation and of zonally asymmetric tropical circulations, as well as the kinetic energy of extratropical baroclinic eddies, can be lower than they presently are both in much warmer climates and in much colder climates. We discuss how latent heat release is implicated in such circulation changes, particularly through its effect on the atmospheric static stability, and we illustrate the circulation changes through simulations with an idealized general circulation model. This allows us to explore a continuum of climates, to constrain macroscopic laws governing this climatic continuum, and to place past and possible future climate changes in a broader context.
Postselection threshold against biased noise

The highest current estimates for the amount of noise a quantum computer can tolerate are based on fault-tolerance schemes relying heavily on postselecting on no detected errors. However, there has been no proof that these schemes give even a positive tolerable noise threshold. A technique to prove a positive threshold, for probabilistic noise models, is presented. The main idea is to maintain strong control over the distribution of errors in the quantum state at all times. This distribution has correlations which conceivably could grow out of control with postselection. But in fact, the error distribution can be written as a mixture of nearby distributions each satisfying strong independence properties, so there are no correlations for postselection to amplify.
Theory of domain wall motion induced by microwave magnetic fields

A general theory is developed that applies to arbitrary polarization and takes account of damping and of the dipolar interaction between domains. The effect of the microwave field on the domain structure can be characterized by a pressure on the domain walls and by an alignment energy, both of which are proportional to the square of the rf magnetic field and become large in the vicinity of a resonance. For circular polarization the pressure tends to decrease the Larmor-domains (domains in which the imposed sense of polarization coincides with the sense of the natural spin precession) for frequencies outside the resonance region. Inside the resonance region, however, the pressure tends to increase the Larmor-domains. A linearly polarized field also exerts a pressure on the domain walls, with the polarity dependent upon the orientation of the field to the wall normal. In a linearly polarized magnetic field the domain walls tend to become aligned parallel to the rf field at frequencies ω near the low-frequency resonance (ω =γH a , γ = gyromagnetic ratio, H a = anisotropy field) and perpendicular to the rf field at frequencies near the high-frequency resonance (ω = γ[H a (H a + 4πM 0 )]1/2, M 0 = saturation magnetization).
Engineering software design processes to guide process execution

Using systematic development processes is an important characteristic of any mature engineering discipline. In current software practice, software design methodologies (SDMs) are intended to be used to help design software more systematically. This paper shows, however, that one well-known example of such an SDM, Booch Object-Oriented Design (BOOD), as described in the literature is too imprecise and incomplete to be considered as a fully systematic process for specific projects. To provide more effective and appropriate guidance and control in software design processes, we applied the process programming concept to the design process. Given two different sets of plausible design process requirements, we elaborated two more detailed and precise design processes that are responsive to these requirements. We have also implemented, experimented with, and evaluated a prototype (called Debus-Booch) that supports the execution of these detailed processes.
Conditional moment restrictions in censored and truncated regression models

Censored and truncated regression models with unknown distribution are important in econometrics. This paper characterizes the class of all conditional moment restrictions that lead to √n-consistent estimators for these models. The semiparametric efficiency bound for each conditional moment restriction is derived. In the case of a nonzero bound it is shown how an estimator can be constructed and that an appropriately weighted version can attain the efficiency bound. These estimators also work when the disturbance is independent of the regressors. The paper discusses combining conditional moment restrictions for more efficient estimation in this case.
An Updated Review of Implantable Cardioverter/Defibrillators, Induced Anxiety, and Quality of Life

Despite overall favorable acceptance of implantable cardioverter-defibrillators (ICDs), patients may experience discharges as frightening and painful. The authors reviewed ICD-induced psychopathology in 2005. During the past 2 years the number of studies examining psychopathology and quality of life after ICD implantation has increased dramatically, warranting this update of that review. Variables assessed have included recipient age, gender, social support network, perception of control and predictability of shocks, and personality style. Now the picture of what is known is, if anything, cloudier than it was 2 years ago, with little definitive and much contradictory data emerging in most of these categories.
Remote sensing of cirrus cloud particle size and optical depth using polarimetric sensor measurements

This paper presents a conceptual approach toward the remote sensing of cirrus cloud particle size and optical depth using the degree of polarization and polarized reflectance associated with the first three Stokes parameters, I, Q, and U, for the 0.865- and 2.25-m wavelengths. A vector line-by-line equivalent radiative transfer program including the full Stokes parameters based on the adding method was developed. The retrieval algorithm employs the steepest-descent method in the form of a series of numerical iteration procedures to search for the simulated polarization parameters that best match the measured values. Sensitivity studies were performed to investigate the behavior of phase-matrix elements as functions of scattering angles for three ice crystal size–shape combinations. Overall, each phase-matrix element shows some sensitivity toward ice crystal shape, size, and surface roughness due to the various optical effects. Synthetic analysis reveals that the retrieval algorithm is highly accurate, while polarimetric and radiometric error sources cause very small retrieval errors. Finally, an illustrative example of applying the retrieval algorithm to airborne Polarization and Directionality of the Earth’s Reflectances (POLDER) data during the European Cloud and Radiation Experiment (EUCREX) is presented.
A Neurological Explanation of Strategic Mortgage Default

This study examines strategic mortgage default on a neurological level. Specifically, we test two mainstream behavioral finance/economic theories: sunk cost fallacy and cognitive dissonance. Using fMRI technology, we identify a number of substrates within the brain that provide a neurobiological explanation for why some homeowners exercise their mortgage put option while others do not. We find that borrowers rationally do not suffer from the sunk cost fallacy as it relates to strategic default in that they significantly prioritize their negative equity position over the amount of their initial down payment. We do, however, find neurological support that cognitive dissonance is relevant in homeowners’ thought processes as they toil with the hesitancy brought on by the believe that strategic default is immoral against the strong financial incentive to walk away from a substantially underwater mortgage.
Diversity, Disparity, and Evolutionary Rate Estimation for Unresolved Yule Trees

The branching structure of biological evolution confers statistical dependencies on phenotypic trait values in related organisms. For this reason, comparative macroevolutionary studies usually begin with an inferred phylogeny that describes the evolutionary relationships of the organisms of interest. The probability of the observed trait data can be computed by assuming a model for trait evolution, such as Brownian motion, over the branches of this fixed tree. However, the phylogenetic tree itself contributes statistical uncertainty to estimates of rates of phenotypic evolution, and many comparative evolutionary biologists regard the tree as a nuisance parameter. In this article, we present a framework for analytically integrating over unknown phylogenetic trees in comparative evolutionary studies by assuming that the tree arises from a continuous-time Markov branching model called the Yule process. To do this, we derive a closed-form expression for the distribution of phylogenetic diversity (PD), which is the sum of branch lengths connecting the species in a clade. We then present a generalization of PD which is equivalent to the expected trait disparity in a set of taxa whose evolutionary relationships are generated by a Yule process and whose traits evolve by Brownian motion. We find expressions for the distribution of expected trait disparity under a Yule tree. Given one or more observations of trait disparity in a clade, we perform fast likelihood-based estimation of the Brownian variance for unresolved clades. Our method does not require simulation or a fixed phylogenetic tree. We conclude with a brief example illustrating Brownian rate estimation for 12 families in the mammalian order Carnivora, in which the phylogenetic tree for each family is unresolved. [Brownian motion; comparative method; Markov reward process; phylogenetic diversity; pure-birth process; quantitative trait evolution; trait disparity; Yule process.]
A note on orthogonal graphs

Orthogonal graphs are natural extensions of the classical binary and b-ary hypercubes b=2/sup l/ and are abstractions of interconnection schemes used for conflict-free orthogonal memory access in multiprocessor design. Based on the type of connection mode, these graphs are classified into two categories: those with disjoint and those with nondisjoint sets of modes. The former class coincides with the class of b-ary b=2/sup l/ hypercubes, and the latter denotes a new class of interconnection. It is shown that orthogonal graphs are Cayley graphs, a certain subgroup of the symmetric (permutation) group. Consequently these graphs are vertex symmetric, but it turns out that they are not edge symmetric. For an interesting subclass of orthogonal graphs with minimally nondisjoint set of modes, the shortest path routing algorithm and an enumeration of node disjoint (parallel) paths are provided. It is shown that while the number of node disjoint paths is equal to the degree, the distribution is not uniform with respect to Hamming distance as in the binary hypercube. >
Individual investors and financial disclosure

Using detailed data of individual investors, this study shows that, on average, individuals invest more in firms with clear and concise financial disclosures. The results indicate this relation is less pronounced for high frequency trading and financially-literate individuals. The study also shows that individuals' returns are increasing with clearer and more concise disclosures, implying such disclosures reduce individuals' relative information disadvantage. Together, the findings suggest improved corporate disclosure practices benefit individual investors, in particular buy-and-hold investors.
A Catalytic Diastereoselective Formal [5+2] Cycloaddition Approach to Azepino[1,2‐a]indoles: Putative Donor–Acceptor Cyclobutanes as Reactive Intermediates

A catalytic formal [5+2] cycloaddition approach to the diastereoselective synthesis of azepino[1,2-a]indoles is reported. The reaction presumably proceeds through a Lewis acid catalyzed formal [2+2] cycloaddition of an alkene with an N-indolyl alkylidene β-amide ester to form a donor-acceptor cyclobutane intermediate, which subsequently undergoes an intramolecular ring-opening cyclization. Azepine products are formed in up to 92% yield with high degrees of diastereoselectivity (up to 34:1 d.r.).
Universal susceptibility variations in 1+1 dimensional vortex glass

We model a planar array of fluxlines as a discrete solid-on-solid (SOS) model with quenched disorder. Simulations at finite temperatures are made possible by a new algorithm that circumvents the slow glassy dynamics encountered by traditional Metropolis Monte Carlo algorithms. Numerical results on magnetic susceptibility variations support analytic predictions.
Optimal quantization for compressive sensing under message passing reconstruction

We consider the optimal quantization of compressive sensing measurements along with estimation from quantized samples using generalized approximate message passing (GAMP). GAMP is an iterative reconstruction scheme inspired by the belief propagation algorithm on bipartite graphs which generalizes approximate message passing (AMP) for arbitrary measurement channels. Its asymptotic error performance can be accurately predicted and tracked through the state evolution formalism. We utilize these results to design mean-square optimal scalar quantizers for GAMP signal reconstruction and empirically demonstrate the superior error performance of the resulting quantizers.
Agricultural policies and trade paths in Turkey

In 1959, shortly after the European Economic Community was founded under the 1957 Treaty of Rome, Turkey applied for Associate Membership in the then six-member common market. By 1963, a path for integrating the economies of Turkey and the eventual European Union had been mapped. As with many trade agreements, agriculture posed difficult political hurdles, which were never fully cleared, even as trade barriers to other sectors were eventually removed and a Customs Union formed. This essay traces the influences the Turkey-European Union economic institutions have had on agricultural policies and the agriculture sector. An applied general equilibrium framework is used to provide estimates of what including agriculture under the Customs Union would mean for the sector and the economy. The paper also discusses the implications of fully aligning Turkey's agricultural policies with the European Union's Common Agricultural Policy, as would be required under full membership.
Phase distortion mechanisms in linear beam vacuum devices

The mechanism for phase distortion in linear beam vacuum devices is identified in the simplest system that pertains to such devices: the force-free drifting electron beam. We show that the dominant cause of phase distortion in a force-free drifting beam is the inverse dependence of arrival time on velocity for an electron, i.e., the "1/u nonlinearity", and that a secondary cause of phase distortion is the nonlinearity of the velocity modulation. We claim that this is the mechanism for phase distortion in all linear beam vacuum devices, and provide evidence from a traveling wave tube calculation. Finally, we discuss the force-free drifting beam example in the context of the "self-intermodulation" description of phase distortion recently described by J. Wohlbier and J. Booske, 2004 and J. Wo/spl uml/hlbier and J. Booske, 2005.
Food Aid and Agricultural Cargo Preference

This paper uses an unprecedentedly rich data set to estimate the cost of agricultural cargo preference (ACP) restrictions on United States food aid programs, and to document some of the programs' competitiveness and national security impacts. ACP cost U.S. taxpayers $140 million in 2006, 46% more than competitive freight costs would have. This roughly equals the cost of non-emergency food aid to Africa. Furthermore, 70% of ACP vessels did not satisfy the criteria that deem them militarily useful, a large share were ultimately owned by foreign corporations, and no ACP vessel crew has been mobilized for national service.
Table-top computed lighting for practical digital photography

We apply simplified image-based lighting methods to reduce the equipment, cost, time, and specialized skills required for high-quality photographic lighting of desktop-sized static objects such as museum artifacts. We place the object and a computer-steered moving-head spotlight inside a simple foam-core enclosure, and use a camera to quickly record low-resolution photos as the light scans the box interior. Optimization guided by interactive user sketching selects a small set of frames whose weighted sum best matches the target image. The system then repeats the lighting used in each of these frames, and constructs a high resolution result from re-photographed basis images. Unlike previous image-based relighting efforts, our method requires only one light source, yet can achieve high resolution light positioning to avoid multiple sharp shadows. A reduced version uses only a hand-held light, and may be suitable for battery-powered, field photography equipment that fits in a backpack.
Multimedia/multimodal signal processing, analysis, and understanding

Summary form only given. "Multimodal" refers to the different senses (visual, audio, tactile, etc.) used in human-computer interface. "Multimedia" refers to the different ways of representing information (text, graphics, audio, images, video, etc.). A signal processing, analysis, or understanding task is called multimedia/multimodal, if it involves two or more modalities or media, interacting in nontrivial ways. We shall give an array of examples of multimedia/multimodal signal processing, analysis, and understanding, including: audio/visual speech recognition, and audio/visual emotion recognition. A stable and robust facial movement tracking algorithm is presented, which is used in both tasks.
Multifocal multiphoton endoscope

We report a miniaturized resonant/non-resonant multi-fiber raster scanner that is paired with a gradient-index assembly to achieve a compact (3 mm OD) multifocal multiphoton endoscope capable of transverse and longitudinal parallel image acquisition.
Pointwise characteristic factors for the multiterm return times theorem

This paper is an update and extension of a result the authors first proved in 2003. The goal of this paper is to study factors which are known to be Lcharacteristic for certain nonconventional averages and prove that these factors are pointwise characteristic for the multiterm return times averages. In memory of Dan Rudolph. Pointwise Characteristic Factors 1
Issues in microwave power systems engineering

The key issues in microwave power system engineering are beam safety, frequency allocation, and affordability. These major issues are presented, discussed, and suggestions for resolving them are offered. The issue of beam safety can be captured in the phrase "Fear of Frying." Can a properly engineered beamed power safety system allay the public perception of microwave radiation dangers? Openness, visibility, and education may be keys to resolving this issue satisfactorily. "Not in my Spectrum" is a phrase that is frequently encountered in connection with the issue of where can the microwave power beam frequency be located. International cooperation may provide a part of the solution to this issue. "Wow, that much!" is a phrase encountered when dealing with the issue of economic affordability of large beamed power systems. A phased engineering approach for multiple uses even during construction is presented to aid in garnering revenue during the system build phase. Also, dual mode DC-RF converters are encouraged for bi-directional power flow utility and economies of scale in production.
Unit commitment considering generator outages through a mixed-integer particle swarm optimization algorithm

The optimum economic operation and planning of electric power generation systems occupies a crucial position in the electric power industry. Unit commitment (UC) is an important function in generation resource management. Moreover, it is nowadays critical to incorporate reliability analysis of the power system into its design of operation strategy. For this purpose, equipment malfunction or failure should be considered in unit commitment. In this paper, first the model for UC considering generator outages is formulated, where the reliability requirement is incorporated into the spinning reserve constraint in the optimization design. Then, a mixed binary- and real-coded particle swarm optimization (PSO) is developed to locate the optimum generation combination. A 10-generator test power system is used to verify the effectiveness of the proposed approach along the 24-h planning horizon. A comparative study is conducted to examine the impact of reliability constraint on the optimal solution obtained. Furthermore, comparison is made between the proposed method and other methods including both analytical and meta-heuristic algorithms.
Poly(norbornene)-supported N-heterocyclic carbenes as ligands in catalysis

In this contribution, we present the synthesis of norbornene-supported N-heterocyclic (NHC) carbenes. These functionalized norbornenes were polymerized via ring-opening metathesis polymerization in a controlled fashion either before or after metalation with a variety of palladium and ruthenium precursors resulting in the formation of polymer-supported NHC-based metal catalysts. The activities of the palladium-based catalysts in the Suzuki–Miyaura, Sonogashira and Heck coupling reactions were studied in detail. In all cases, the polymeric catalysts demonstrated the same activity as their small molecule analogues. Furthermore, we carried out preliminary investigations into the stability of these catalysts using poisoning studies. A clear dependence of the stability of the polymer-supported catalysts on their palladium precursor was observed with palladium acetate-based polymeric NHC catalysts being the most stable. Finally, we have studied the reactivity of our supported NHC ruthenium complexes as catalysts for ring-closing metathesis. Again, in all cases good conversions were observed with comparable activities to other supported NHC-ruthenium catalysts. Lastly, we were able to remove the ruthenium catalysts from the solution quantitatively demonstrating the possibility of metal removal.
Leptonic observables in ultra-relativistic heavy-ion collisions

Abstract We report on leptonic observables by the PHENIX experiment from data taken during Run II at the Relativistic Heavy Ion Collider (RHIC). We show first results on φ → K+K−, e+e−, low and intermediate mass dielectron continuum, single electrons from charm, and J/ψ yields in proton-proton and Au Au collisions at S N N = 200 GeV.
A periodic fixed-structure approach to multirate control

We develop an approach to designing reduced-order multirate controllers. A discrete-time model that accounts for the multirate timing sequence of measurements is presented and is shown to have periodically time-varying dynamics. Using discrete-time stability theory, the optimal projection approach to fixed-order (i.e. full- and reduced-order) dynamic compensation is generalized to obtain reduced-order periodic controllers that account for the multirate architecture. It is shown that the optimal reduced-order controller is characterized by means of a periodically time-varying system of equations consisting of coupled Riccati and Lyapunov equations. In addition, the multirate static output-feedback control problem is considered. For both problems, the design equations are presented in a concise, unified manner to facilitate their accessibility for developing numerical algorithms for practical applications. >
Individuals and Identity in Economics

This book examines the different conceptions of the individual that have emerged in recent new approaches in economics, including behavioral economics, experimental economics, social preferences approaches, game theory, neuroeconomics, evolutionary and complexity economics, and the capability approach. These conceptions are classified according to whether they seek to revise the traditional atomist individual conception, put new emphasis on interaction and relations between individuals, account for individuals as evolving and self-organizing, and explain individuals in terms of capabilities. The method of analysis uses two identity criteria for distinguishing and re-identifying individuals to determine whether these different individual conceptions successfully identify individuals. Successful individual conceptions account for sub-personal and supra-personal bounds on single individual explanations. The former concerns the fragmentation of individuals into multiple selves; the latter concerns the dissolution of individuals into the social. The book develops an understanding of bounded individuality, seen as central to the defense of human rights.
A one-way coupled, Euler–Lagrangian simulation of bubble coalescence in a turbulent pipe flow

A bubble coalescence model is developed using an Euler–Lagrangian approach for unstructured grids. The Eulerian carrier fluid is solved using large-eddy simulation (LES) and the Lagrangian particle motion is solved with equations relating the turbulent motion of the carrier fluid to forces on each discrete bubble. The collision process is deterministic; bubble–bubble collisions are assumed to be binary and are modeled using a hard-sphere approach. A stochastic approach is used to model coalescence, with the probability of coalescence being a function of the bubble–bubble interaction timescale and the time to drain fluid between the colliding bubbles. The intention is to develop and validate the collision and coalescence model, neglecting two-way coupling turbulent subgrid stress transport of bubbles and the modification of the subgrid stress by the bubbles. Coalescence in a bubbly, turbulent pipe flow in microgravity is simulated with conditions similar to experiments by Colin et al. (Colin, C., Fabre, J., Dukler, A.E., 1991. Gas–liquid flow at microgravity conditions – I. Dispersed bubble and slug flow. Int. J. Multiphase Flow 17 (4), 533–544.) and excellent agreement of bubble size distribution is obtained between simulation and experiment. With increasing downstream distance, the number density of bubbles decreases due to coalescence and the average probability of coalescence decreases slightly due to an increase in overall bubble size.
Farming Exit Decision by Age Group: Analysis of Tobacco Buyout Impact in Kentucky

This article analyzes factors that affected the decision to exit tobacco production in the wake of the tobacco buyout program using the data collected through a survey of Kentucky tobacco farmers. Using the Heuristic logistic regression model, we find that the decision to exit tobacco growing was affected by efficiency considerations, availability of off-farm employment, and exit barriers. Availability of off-farm employment had the strongest effect on farmers younger than 46, while the effect of variables measuring efficiency and exit barriers seemed to be more uniform across age groups. Based on the results we suggest several policy interventions.
Is there a tendency for the rate of profit to fall? Econometric evidence for the U.S. economy, 1948-2007

The law of the tendential fall in the rate of profit has been at the center of theoretical and empirical debates within Marxian political economy since the publication of volume III of Capital. An important limitation of this literature is the relative paucity of modern econometric investigations of the behavior of the rate of profit. The central objective of this paper is to remedy this lacuna. We investigate the properties of the profit rate series utilizing the methods of time series econometrics. The evidence suggests that the rate of profit is non-stationary. We also specify a test of Marx’s law of the tendential fall in the rate of profit with a novel econometric model that explicitly accounts for the counter-tendencies and their time series properties. We find weak evidence of a long-run downward trend in the general profit rate for the U.S. economy for the period 1948-2007.JEL Codes: B51, C22, E11.
Grain fragmentation in sheared granular flow: weakening effects, energy dissipation, and strain localization.

We describe the shear flow of a disordered granular material in the presence of grain fracture using the shear-transformation-zone theory of amorphous plasticity adapted to systems with a hard-core interparticle interaction. To this end, we develop the equations of motion for this system within a statistical-thermodynamic framework analogous to that used in the analysis of molecular glasses. For hard-core systems, the amount of internal, configurational disorder is characterized by the compactivity $X=\ensuremath{\partial}V/\ensuremath{\partial}{S}_{C}$, where $V$ and ${S}_{C}$ are, respectively, the volume and configurational entropy. Grain breakage is described by a constitutive equation for the temporal evolution of a characteristic grain size $a$, based on fracture mechanics. We show that grain breakage is a weakening mechanism, significantly lowering the flow stress at large strain rates, if the material is rate strengthening in character. We show in addition that if the granular material is sufficiently aged, spatial inhomogeneity in configurational disorder results in strain localization. We also show that grain splitting contributes significantly to comminution at small shear strains, while grain abrasion becomes dominant at large shear displacements.
SILICA IN PROTOPLANETARY DISKS

Mid-infrared spectra of a few T Tauri stars (TTS) taken with the Infrared Spectrograph on board the Spitzer Space Telescope show prominent narrow emission features indicating silica (crystalline silicon dioxide). Silica is not a major constituent of the interstellar medium; therefore, any silica present in the circumstellar protoplanetary disks of TTS must be largely the result of processing of primitive dust material in the disks surrouding these stars. We model the silica emission features in our spectra using the opacities of various polymorphs of silica and their amorphous versions computed from earth-based laboratory measurements. This modeling indicates that the two polymorphs of silica, tridymite and cristobalite, which form at successively higher temperatures and low pressures, are the dominant forms of silica in the TTS of our sample. These high-temperature, low-pressure polymorphs of silica present in protoplanetary disks are consistent with a grain composed mostly of tridymite named Ada found in the cometary dust samples collected from the STARDUST mission to Comet 81P/Wild 2. The silica in these protoplanetary disks may arise from incongruent melting of enstatite or from incongruent melting of amorphous pyroxene, the latter being analogous to the former. The high temperatures of ∼ 1200–1300 K and rapid cooling required to crystallize tridymite or cristobalite set constraints on the mechanisms that could have formed the silica in these protoplanetary disks, suggestive of processing of these grains during the transient heating events hypothesized to create chondrules.
The average sensitivity of an intersection of half spaces

We prove new bounds on the average sensitivity of the indicator function of an intersection of k halfspaces. In particular, we prove the optimal bound of O(√nlog(k)). This generalizes a result of Nazarov, who proved the analogous result in the Gaussian case, and improves upon a result of Harsha, Klivans and Meka. Furthermore, our result has implications for the runtime required to learn intersections of halfspaces.
Nanoalloy catalysts for electrochemical energy conversion and storage reactions

A key challenge to the exploration of electrochemical energy conversion and storage is the ability to engineer the catalyst with low cost, high activity and high stability. Existing catalysts often contain a high percentage of noble metals such as Pt and Pd. One important approach to this challenge involves alloying noble metals with other transition metals in the form of a nanoalloy, which promises not only significant reduction of noble metals in the catalyst but also enhanced catalytic activity and stability in comparison with traditional approaches. In this article, some of the recent insights into the structural and electrocatalytic properties of nanoalloy catalysts in which Pt is alloyed with a second and/or third transition metal (M/M′ = Co, Fe, V, Ni, Ir, etc.), for electrocatalytic oxygen reduction reaction and ethanol oxidation reaction in fuel cells, and oxygen reduction and evolution reactions in rechargeable lithium-air batteries are highlighted. The correlation of the electrocatalytic properties of nanoalloys in these systems with the atomic-scale chemical/structural ordering in the nanoalloy is an important focal point of the investigations, which has significant implications for the design of low-cost, active, and durable catalysts for sustainable energy production and conversion reactions.
Stocking Rate and Weather Impacts on Sand Sagebrush and Grasses: A 20-Year Record

Abstract Understanding how stocking rate or grazing intensity affects the abundance of common plant species is fundamental to the sustainable management of rangelands. We had the unique opportunity to determine the impact of stocking rate on shrub canopy cover and grass basal cover in a sand sagebrush (Artemisia filifolia Torr.) grassland of the Southern Plains, United States. Treatments were imposed over a 20-year time span that included an entire precipitation cycle from wet to dry and back to wet conditions. From 1941 until 1951, continuous stocking treatments of 41, 53, and 82 animal-unit-days ha−1 (AUD·ha−1) were imposed with straight-bred Hereford steers (initial weight of 213 kg ± 11 SE) for about 320 days from mid-November to late September of the next year. From 1952 through 1961, the experimental pastures were grazed yearlong by cow-calf pairs at 45, 60, and 87 AUD·ha−1. Canopy cover of shrubs and basal cover of grasses were measured by the line-intercept method in 1940, 1942, 1949, 1955, 1958, ...
Geographic gossip on geometric random graphs via affine combinations

In recent times, a considerable amount of work has been devoted to the development and analysis of gossip algorithms in Geometric Random Graphs. In a recently introduced model termed "Geographic Gossip," each node is aware of its position but possesses no further information. We develop a new protocol for Geographic Gossip, in which counter-intuitively, we use "non-convex affinecombinations" as updates in addition to convex combinations to accelerate the averaging process.
Dispute Resolution in Ottoman Courts: A Quantitative Analysis of Litigations in Eighteenth-Century Kastamonu

Since the emergence of the Weberian notion of “kadijustiz” scholars have debated the ability of Islamic courts to resolve disputes fairly and predictably. For a quantitative analysis of how these courts resolved disputes, we use data from the court records (sicils) of the Ottoman town of Kastamonu and examine whether the judges’ decision followed systematic patterns and whether the patterns were logical. The results show that the trial outcome was influenced by the gender, elite status, religion, and religious markers of litigants. Using the tools and concepts of modern scholarship on dispute resolution, we argue that in resolving disputes Kastamonu courts displayed logical patterns that are consistent with those identified by quantitative analysis of court outcomes in modern societies.
Foam: Multi-dimensional general purpose Monte Carlo generator with self-adapting simplical grid

A new general purpose Monte Carlo event generator with self-adapting grid consisting of simplices is described. In the process of initialization, the simplex-shaped cells divide into daughter subcells in such a way that: (a) cell density is biggest in areas where integrand is peaked, (b) cells elongate themselves along hyperspaces where integrand is enhanced/singular. The grid is anisotropic, i.e. memory of the axes directions of the primary reference frame is lost. In particular, the algorithm is capable of dealing with distributions featuring strong correlation among variables (like ridge along diagonal). The presented algorithm is complementary to others known and commonly used in the Monte Carlo event generators. It is, in principle, more eective then any other one for distributions with very complicated patterns of singularities { the price to pay is that it is memory-hungry. It is therefore aimed at a small number of integration dimensions (< 10). It should be combined with other methods for higher dimension. The source code in Fortran77 is available from http://home.cern.ch/jadach. To be submitted to Comput. Phys. Commun.
Enhanced Bipolar Stacked Switched Capacitor Energy Buffers

The stacked switched capacitor (SSC) energy buffer is a recently proposed architecture for buffering energy between single-phase alternating and direct current. When used with film capacitors, it can increase the life of grid-interfaced power converters by eliminating limited-life electrolytic capacitors while maintaining comparable energy density. This paper introduces an enhanced version of the bipolar SSC energy buffer that achieves higher effective energy density and round-trip efficiency while maintaining the same bus voltage ripple ratio as the original design. Furthermore, the enhanced buffer uses fewer capacitors and switches than the original design. The enhancement in performance is achieved by modifying the control and switching patterns of the buffer switches. A prototype enhanced SSC energy buffer, designed for a 320-V bus and a 135-W load, has been built and tested. The design methodology and experimental results for the enhanced SSC energy buffer are presented and compared with the original design. This paper also presents a comparison of unipolar and bipolar SSC energy buffers. It is shown that, although bipolar designs are superior in terms of effective energy density at low ripple ratios, unipolar designs can outperform bipolar designs at high ripple ratios.
Optical Properties of faint FIRST Variable Radio Sources

A sample of 123 radio sources that exhibit significant variations at 1.4 GHz on a 7 year baseline has been created using FIRST VLA B-configuration data from 1995 and 2002 on a strip at δ = 0 near the south Galactic cap. This sample spans the range of radio flux densities from ~2 to 1000 mJy. It presents both in size and radio flux density range a unique starting point for variability studies of galaxies and quasars harboring lower luminosity active galactic nuclei (AGNs). We find, by comparing our variable and nonvariable control samples with the Sloan Digital Sky Survey, the following: (1) The quasar fraction of both the variable and nonvariable samples declines as a function of declining radio flux density levels; (2) our variable sample contains a consistently higher fraction of quasars than the nonvariable control sample, irrespective of radio flux; (3) the variable sources are almost twice as likely to be retrieved from the optical SDSS data than the nonvariable ones; (4) based on relative numbers, we estimate that quasars are about 5 times more likely to harbor a variable radio source than are galaxies; and (5) there does not appear to be any significant optical color offset between the two samples, even though the suggestive trend for sources to be bluer when a variable has been detected before and may be real. This leads us to conclude that both radio variability and radio flux density levels, in combination with accurate optical information, are important discriminators in the study of (radio) variability of galaxies. The latter start to dominate the source counts below ~20 mJy. In any case, variability appears to be an intrinsic property of radio sources and is not limited to quasars. Radio variability at low flux density levels may offer a unique tool in AGN unification studies.
Molybdenum carbene complexes : cyclopropanation of electron-poor olefins

Abstract Fischer carbene complexes of molybdenum have been prepared and found to readily cyclopropanate electron-poor olefins in good yield.
Copper-promoted N-arylations of cyclic imides within six-membered rings: a facile route to arylene-based organic materials.

Cyclic imides within six-membered rings are shown to undergo efficient N-arylation using various arylboronic esters mediated by copper(II) acetate in the presence of an amine base and oxygen atmosphere with gentle heating. Until now, the synthesis of N-arylated cyclic imides having six-membered rings was restricted largely to strongly heating anilines in the presence of anhydrides. This reaction is applicable to the synthesis of new organic materials based on arylene imide and bis(imide) dyes, such as perylene-3,4:9,10-bis(dicarboximide)s.
Language modeling for soft keyboards

We describe how language models, combined with models of pen placement, can be used to significantly reduce the error rate of soft keyboard usage, by allowing for cases in which a key press is outside of a key boundary. Language models predict the probabilities of words or letters. Soft keyboards are images of keyboards on a touch screen used for input on Personal Digital Assistants. When a soft keyboard user hits a key near the boundary of a key position, we can use the language model and key press model to select the most probable key sequence, rather than the sequence dictated by strict key boundaries. This leads to an overall error rate reduction by a factor of 1.67 to 1.87.
What Explains the Varying Monetary Response to Technology Shocks in G-7 Countries?

In a recent paper, Gali, Lopez-Salido, and Vallees (2003) examined the Federal Reserve’s response to VAR-identified technology shocks. They found that during the Martin-Burns- Miller era, the Federal Reserve responded to technology shocks by overstabilizing output, while in the Volcker-Greenspan era, the Federal Reserve adopted an inflation-targeting rule. We extend their analysis to countries of the G-7; moreover, we consider the factors that may contribute to differing monetary responses across countries. Specifically, we find a relationship between the volatility of capital investment, the type of monetary policy rule, the responsiveness of the rule to output and inflation fluctuations, and the response to technology shocks.
Bootstrap methods for stochastic prediction of voltage sags

This paper illustrates the use of resampling bootstrap methods for stochastic prediction of voltage sags from limited monitoring data. Using results from phase II of EPRI's distribution power quality study; we illustrate different resampling techniques that can be used to estimate a system's power quality. These resampling methods are compared with parametric approach, which assumes a certain probability distribution. Resampling techniques are powerful tools in analyzing variability and uncertainty in nonnormal data sets in power distribution systems.
Buyer Market Power and Vertically Differentiated Retailers

We consider a model of vertical competition where downstream firms (retailers) purchase an upstream input from a monopolist and are able to differentiate from each other in terms of quality. Our primary focus is to study the effects of introducing a large retailer, such as a WalMart Supercenter, that is able to lower wholesale prices (i.e. buyer market power). We obtain two main results. First, the store with no buyer market power responds to the presence of the large retailer by increasing its quality, a finding that is consistent with recent efforts by traditional retailers to enhance shoppers’ buying experience (i.e. quality). Second, the presence of a large retailer causes consumer welfare to increase. There are, however, two reasons for the increase in consumer welfare: consumers gain from the large retailer’s low price (because the upstream discount is partially passed on to the retail price) as well as from the high quality level offered by the traditional retailer. Contrary to the conventional wisdom most of the consumer welfare gains seem due to the latter. The intuition for this result is that price competition softens substantially as a result of firms’ quality differentiation. We also investigate the effects of buyer market power on retail and wholesale prices as well as on producer welfare.