cssi/SciSciGPT-SciSciNet huggingface dataset:
The Cauchy Data and the Scattering Relation

As mentioned in the preface to this volume a combination of unique continuation results with the boundary control method has led to the solution of the inverse problem of determining a metric of a Riemannian manifold (with boundary) from the dynamic Dirichlet-to-Neumann map associated with the wave equation. Although these results are very satisfactory it requires too much information. By just looking at the singularities of the dynamic Dirichlet-to-Neumann (DN) map one can determine the boundary distance function (the minimal travel time along geodesies connecting points on the boundary of a Riemannian manifold) in the case that there are no conjugate points of the metric, i. e. no caustics. This is shown in Section 3 of this article using geometrical optics expansions. A natural question to ask if one can determine the metric from this data alone; this question is at the center of the boundary rigidity problem studied in Riemannian geometry which is one of the main topics of this volume.
Competition and demographics

Mainstream economics views demographic changes in the structure of households as of little relevance for the behavior of firms or the functioning of markets. The present paper dispels this view by arguing that changes in the number of non-workers could affect the intensity with which consumers search for best prices and therefore the level of competition. The author also analyzes the relationship between income and competition, which some studies suggest is negative. The author argues that the negative relationship is most likely due to the demographic factors discussed.
On the Homflypt skein module of S^1 x S^2

Let k be a subring of the field of rational functions in x, v,s which contains $x^{\pm 1}, v^{\pm 1}, s^{\pm 1}$ . If M is an oriented 3-manifold, let $S(M)$ denote the Homflypt skein module of M over k. This is the free k-module generated by isotopy classes of framed oriented links in M quotiented by the Homflypt skein relations: (1) $x^{-1}L_{+}-xL_{-}=(s-s^{-1})L_{0}$ ; (2) L with a positiv e twist $=(xv^{-1})L$ ; (3) $L\sqcup O=(\frac{v-v^{-1}}{s-s^{-1}})L$ where O is the unknot. We give two bases for the relative Homflypt skein module of the solid torus with 2 points in the boundary. The first basis is related to the basis of $S(S^1\times D^2)$ given by J. Hoste and M. Kidwell and also V. Turaev; the second basis is related to a Young idempotent basis for $S(S^1\times D^2)$ based on the work of A. Aiston, H. Morton and C. Blanchet. We prove that if the elements $s^{2n}-1$ , for n a nonzero integer, and the elements $s^{2m}-v^{2}$ , for any integer m, are invertible ink, then $S(S^{1} \times S^2)=k$ -torsion module $\oplus k$ . Here the free part is generated by the empty link $\phi$ . In addition, if the elements $s^{2m}-v^{4}$ , for m an integer, are invertible in k, then $S(S^{1} \times S^2)$ has no torsion. We also obtain some results for more general k.
The Functions of Trust Law: a Comparative Legal and Economic Analysis

This Article analyzes the functions served by the law of trusts and asks, first, whether the basic tools of contract and agency law could fulfill the same functions and, second, whether trust law provides benefits that are not provided by the law of corporations. The analysis is motivated in part by the increasing interest in the trust -- a familiar feature of common-law jurisdictions -- in a number of civil law countries, and in part by the important role that trusts, such as pension funds and mutual funds, have come to play in capital markets. The article concludes that the important contribution of trust law lies not in its well-recognized role of ordering, via default rules of contract, the relationships among the principal parties to the trust. Rather, the principal benefit of trust law lies in its ordering of relationships between those parties and third parties with whom they deal, relationships that cannot easily be rearranged by contract. Most conspicuously in this respect, trust law allows the parties to the trust to partition off a discrete set of assets for separate treatment in relationships formed with creditors. The essential role of the trust, therefore, is to perform a property law-like, rather than a contract law-like, function. The article also notes the increasing convergence of trust law and corporate law, and asks whether the roles performed by these two legal forms could just as well be served by a single form.
Canonical Elements for Collision Orbits

I derive a set of canonical elements that are useful for collision orbits (perihelion distance approaching zero at fixed semimajor axis). The coordinates are the mean anomaly and the two spherical polar angles at aphelion.
A generative model based approach to motion segmentation

We address the question of how to choose between different likelihood functions for motion estimation. To this end, we formulate motion estimation as a problem of Bayesian inference and compare the likelihood functions generated by various models for image formation. In contrast to alternative approaches which focus on noise in the measurement process, we propose to introduce noise on the level of the velocity, thus allowing it to vary around a given model. We show that this approach generates additional normalizations not present in previous likelihood functions. We numerically evaluate the proposed likelihood in a variational framework for segmenting the image plane into domains of piecewise constant motion. The evolution of the motion discontinuity set is implemented using the level set framework.
Modular Internet Programming with Cells

The success of Java in recent years is largely due to its targeting as a language for the Internet. Many of the network-related features of Java however are not part of the core language design. In this paper we focus on the design of a more parsimonious Internet programming language, which supports network integration smoothly and coherently as part of its core specification.The key idea is to center these extensions around the unified notion of a cell. Cells are deployable containers of objects and code, which may import (plugin) and export (plugout) classes and operations. They may be dynamically linked and unlinked, locally or across the network. Cells may be dynamically loaded, unloaded, copied, and moved, and serve as units of security. At first approximation, cells can be thought of as a hybrid between modules and components. Here we concentrate on the design of JCells, a language which builds cells on top of the fundamental Java notions of class, object, and virtual machine.
Continuous time bayesian networks

In this paper we present a language for finite state continuous time Bayesian networks (CTBNs), which describe structured stochastic processes that evolve over continuous time. The state of the system is decomposed into a set of local variables whose values change over time. The dynamics of the system are described by specifying the behavior of each local variable as a function of its parents in a directed (possibly cyclic) graph. The model specifies, at any given point in time, the distribution over two aspects: when a local variable changes its value and the next value it takes. These distributions are determined by the variable's current value and the current values of its parents in the graph. More formally, each variable is modelled as a finite state continuous time Markov process whose transition intensities are functions of its parents. We present a probabilistic semantics for the language in terms of the generative model a CTBN defines over sequences of events. We list types of queries one might ask of a CTBN, discuss the conceptual and computational difficulties associated with exact inference, and provide an algorithm for approximate inference which takes advantage of the structure within the process.
REVISITING BID DESIGN ISSUES IN CONTINGENT VALUATION

A uniform bid design from a predetermined uniform distribution is proposed as a practical and robust alternative to existing optimal or naive bid designs. Analytics and simulations show that the uniform design provides efficiency better than naive designs under ideal conditions and outperforms optimal designs with poor initial information.
Grand challenges for wireless sensor networks

The technological advances in the micro-electro-mechanical systems (MEMS) and the wireless communications have enabled the deployment of the small intelligent sensor nodes at homes, in workplaces, supermarkets, plantations, oceans, streets, and highways to monitor the environment. The realization of smart environments to improve the efficiency of nearly every aspect of our daily lives by enhancing the human-to-physical world interaction is one of the most exciting potential sensor network applications utilizing these intelligent sensor nodes. However, this objective necessitates the efficient and application specific communication protocols to assure the reliable communication of the sensed event features and hence enable the required actions to be taken by the actors in the smart environment. In this talk, the grand challenges for the design and development of sensor/actor network communication protocols are presented. More specifically, application layer, transport layer, network layer, data link layer, in particular, error control and MAC protocols, and physical layer as well as cross layer issues are explained in detail.
A second order difference scheme for transient semiconductor device simulation

Abstract : A second order scheme for the solution of the transient fundamental semiconductor device equations is presented which does not suffer from timestep restrictions due to the stiffness of the analytical problem. The second order accuracy as well as the stability properties are demonstrated on the simulation of a p-n-junction diode. keywords: Semiconductors; Singular Perturbations; Finite Differences.
The Economics Of Growing And Delivering Cellulosic Feedstocks In The Beaumont, Texas Area

Abstract We estimate the contract prices that must be paid to grow cellulosic energy crops, and the costs of harvesting and transporting those crops in the Beaumont, TX area. Results indicate that the delivered price would range between $54 and $101 per ton of dry matter depending on the specific crop. Introduction Annual production of ethanol for fuel in the United States has risen from 175 million gallons in 1980 to nearly 5 billion gallons in 2006 (Renewable Fuels Association (RFA)). While nearly all of the U.S. ethanol supply is currently derived from corn, concerns about environmental sustainability and potential impacts on the food supply chain have brought corn-based ethanol out of favor with some. Advanced biofuels such as cellulosic ethanol are expected to be the preferable long-term source of renewable energy (Council for Agricultural Science and Technology (CAST)). The recently enacted Energy Independence and Security Act of 2007, mandates that the United States produce 16 billion gallons of cellulosic biofuel by 2022, representing 44% of the total biofuel mandate (Wyant). The push for cellulosic ethanol has prompted the Department of Energy (DOE) to award millions in cellulosic research grants (DOE). The southeastern United States, from the upper coast of Texas to northern Florida, is viewed by some private sector grant recipients as potentially being the most agronomically favorable geographic region for cellulosic feedstock (biomass) production. However the 2
Probabilities of causation: bounds and identification

This paper deals with the problem of estimating the probability that one event was a cause of another in a given scenario. Using structural-semantical definitions of the probabilities of necessary or sufficient causation (or both), we show how to optimally bound these quantities from data obtained in experimental and observational studies, making minimal assumptions concerning the data-generating process. In particular, we strengthen the results of Pearl (1999) by weakening the data-generation assumptions and deriving theoretically sharp bounds on the probabilities of causation. These results delineate precisely how empirical data can be used both in settling questions of attribution and in solving attribution-related problems of decision making.
Lattice model of linear telechelic polymer melts. II. Influence of chain stiffness on basic thermodynamic properties

The lattice cluster theory (LCT) for semiflexible linear telechelic melts, developed in Paper I, is applied to examine the influence of chain stiffness on the average degree of self-assembly and the basic thermodynamic properties of linear telechelic polymer melts. Our calculations imply that chain stiffness promotes self-assembly of linear telechelic polymer melts that assemble on cooling when either polymer volume fraction ϕ or temperature T is high, but opposes self-assembly when both ϕ and T are sufficiently low. This allows us to identify a boundary line in the ϕ-T plane that separates two regions of qualitatively different influence of chain stiffness on self-assembly. The enthalpy and entropy of self-assembly are usually treated as adjustable parameters in classical Flory-Huggins type theories for the equilibrium self-assembly of polymers, but they are demonstrated here to strongly depend on chain stiffness. Moreover, illustrative calculations for the dependence of the entropy density of linear telechelic polymer melts on chain stiffness demonstrate the importance of including semiflexibility within the LCT when exploring the nature of glass formation in models of linear telechelic polymer melts.
Labor Matching Model: Putting the Pieces Together

The original Mortensen-Pissarides model possesses two elements that are absent from the commonly used simplified version: the job destruction margin and training costs. I find that these two elements enable a model driven only by productivity shocks to simultaneously explain most of the movements in unemployment, vacancies, job destruction, job creation, the job finding rate and wages. The role of the job destruction margin in propagating productivity shocks is to create an additional pool of unemployed at the very beginning of a recession. The role of training costs is to explain the simultaneous decline in vacancies.
Electric-field dependent spin diffusion and spin injection into semiconductors

We derive a drift-diffusion equation for spin polarization in semiconductors by consistently taking into account electric-field effects and nondegenerate electron statistics. We identify a high electric-field diffusive regime which has no analog in metals. In this regime there are two distinct spin-diffusion lengths. Furthermore, spin injection from a ferromagnetic metal into a semiconductor is enhanced by several orders of magnitude. This enhancement also occurs for high electric-field spin injection through a spin-selective interfacial barrier.
Poverty, Living Conditions, and Infrastructure Access : A Comparison of Slums in Dakar, Johannesburg, and Nairobi

In this paper the authors compare indicators of development, infrastructure, and living conditions in the slums of Dakar, Nairobi, and Johannesburg using data from 2004 World Bank surveys. Contrary to the notion that most African cities face similar slum problems, find that slums in the three cities differ dramatically from each other on nearly every indicator examined. Particularly striking is the weak correlation of measures of income and human capital with infrastructure access and quality of living conditions. For example, residents of Dakar's slums have low levels of education and high levels of poverty but fairly decent living conditions. By contrast, most of Nairobi's slum residents have jobs and comparatively high levels of education, but living conditions are but extremely bad . And in Johannesburg, education and unemployment levels are high, but living conditions are not as bad as in Nairobi. These findings suggest that reduction in income poverty and improvements in human development do not automatically translate into improved infrastructure access or living conditions. Since not all slum residents are poor, living conditions also vary within slums depending on poverty status. Compared to their non-poor neighbors, the poorest residents of Nairobi or Dakar are less likely to use water (although connection rates are similar) or have access to basic infrastructure (such as electricity or a mobile phone). Neighborhood location is also a powerful explanatory variable for electricity and water connections, even after controlling for household characteristics and poverty. Finally, tenants are less likely than homeowners to have water and electricity connections.
Political Legitimacy and Technology Adoption

A fundamental question of economic and technological history is why some civilizations adopted new and important technologies and others did not. In this paper, we construct a simple political-economy model that suggests that rulers may not accept a productivity-enhancing technology when it negatively affects an agent's ability to provide the ruler legitimacy. However, when other sources of legitimacy emerge, the ruler will accept the technology as long as the new legitimizing source is not negatively affected. This insight helps explain the initial blocking but eventual accepting of the printing press in the Ottoman Empire and industrialization in tsarist Russia.
THE LOCAL INFLUENCE OF PIONEER INVESTIGATORS ON TECHNOLOGY ADOPTION: EVIDENCE FROM NEW CANCER DRUGS.

Local opinion leaders may play a key role in easing information frictions associated with technology adoption. This paper analyzes the influence of physician investigators who lead clinical trials for new cancer drugs. By comparing diffusion patterns across 21 new cancer drugs, we separate correlated regional demand for new technology from information spillovers. Patients in the lead investigator’s region are initially 36% more likely to receive the new drug, but utilization converges within four years. We also find that superstar physician authors, measured by trial role or citation history, have broader influence than less prominent authors.
Graphene junction field-effect transistor

Graphene is known for its high carrier mobility and high saturation velocity [1–3]. The majority of graphene transistors in the literature—including MOSFETs, barristors, and tunneling FETs—have a gate separated from the channel by a conventional or high-K dielectric layer [4–6]. In this paper we demonstrate for the first time a lateral graphene FET gated by a graphene/semiconductor heterojunction. The device consists of a p-type graphene channel and an n-type semiconductor gate. Since no metal/dielectric-stacked gate is used, the device is referred to as graphene junction FET (G-JFET). Such a device is of interest as an alternate to G-MOSFETs, or as a back gate for G-MOSFETs with the feature that the device's Dirac voltage (V Dirac ) can be tuned by the doping density of semiconductor gate.
Conservation Policy and Land Value: The Conservation Reserve Program

This paper quantifies the effects of the Conservation Reserve Program (CRP) on farmland and developed land prices. Results show that the CRP increases farmland and developed land prices by 1.8% and 0.6%, respectively, on national average, with the largest increases in the Mountain, Southern Plains, and Northern Plains.
A Novel Route to N-Styrylamides

Abstract A general synthesis of N-styrylamides starting from amides and phenylacetaldehyde is described. Condensation of the amide, aldehyde and benzotriazole affords N-(1-benzotriazol-l-yl-2-phenylethyl)amides 2 from which the benzotriazole molecule is smoothly eliminated.
What Does Infant Feeding Mean to African American Women and Their Support Persons

Poster Presentation Objective To understand and describe infant feeding practices of African American mothers as well as the infant feeding perceptions and experiences of their support persons. Design A qualitative critical ethnographic research design. Setting Participants were recruited from community‐based, public health, and home visiting programs. Sample A purposive sample of 14 pregnant African American women and eight support persons were recruited. Methods Twenty‐two participants (14 pregnant women and eight support persons) were interviewed about and observed for infant feeding decisions during the antepartum and postpartum periods using a critical ethnographic approach. Through thematic analysis, key themes were identified. Results Most participants intended to breastfeed exclusively before birth and noted the importance of breastfeeding and its benefits for mothers and infants. Yet combination feeding (the use of breast milk and formula) was a common occurrence after birth, and participants felt guilty for not being able to breastfeed exclusively. Life experiences (e.g., lack of breastfeeding role models, education and/or employment aspirations) also played a role in intentions and perceptions about breastfeeding. Conclusion/Implications for Nursing Practice These data suggest African American women want to breastfeed and that future interventions geared toward this population should include messaging related to combination feeding and increased support for all mothers regardless of their infant feeding methods. Public health measures aimed at reducing the current infant feeding disparities would benefit by incorporating a more culturally inclusive messages related to breastfeeding.
Dimensionally Challenged Gravities

I review some ways through which spacetime dimensionality enters explicitly in gravitation. In particular, I recall the unusual geometrical gravity models that are constructible in dimensions different from four, especially in D=3 where even ordinary Einstein theory is “different,” e.g., fully Machian.
A variational approximation for Bayesian networks with discrete and continuous latent variables

We show how to use a variational approximation to the logistic function to perform approximate inference in Bayesian networks containing discrete nodes with continuous parents. Essentially, we convert the logistic function to a Gaussian, which facilitates exact inference, and then iteratively adjust the variational parameters to improve the quality of the approximation. We demonstrate experimentally that this approximation is much faster than sampling, but comparable in accuracy. We also introduce a simple new technique for handling evidence, which allows us to handle arbitrary distributionson observed nodes, as well as achieving a significant speedup in networks with discrete variables of large cardinality.
Parameter Estimation Techniques Based on Optimizing Goodness-of-Fit Statistics for Structural Reliability

New methods are presented that utilize the optimization of goodness-of-fit statistics in order to estimate Weibull parameters from failure data. It is assumed that the underlying population is characterized by a three-parameter Weibull distribution. Goodness-of-fit tests are based on the empirical distribution function (EDF). The EDF is a step function, calculated using failure data, and represents an approximation of the cumulative distribution function for the underlying population. Statistics (such as the Kolmogorov-Smirnov statistic and the Anderson-Darling statistic) measure the discrepancy between the EDF and the cumulative distribution function (CDF). These statistics are minimized with respect to the three Weibull parameters. Due to nonlinearities encountered in the minimization process, Powell's numerical optimization procedure is applied to obtain the optimum value of the EDF. Numerical examples show the applicability of these new estimation methods. The results are compared to the estimates obtained with Cooper's nonlinear regression algorithm.
Planetary geology in the 1980s

The geologic aspects of solar system studies are defined and the goals of planetary geology are discussed. Planetary geology is the study of the origin, evolution, and distribution of matter condensed in the form of planets, satellites, asteroids, and comets. It is a multidisciplinary effort involving investigators with backgrounds in geology, chemistry, physics, astronomy, geodesy, cartography, and other disciplines concerned with the solid planets. The report is primarily restricted to the kinds of experiments and observations made through unmanned missions.
Influence of hurricane‐related activity on North American extreme precipitation

Despite the catastrophic societal costs of hurricanes and considerable recent attention to possible trends, little is known about the general contribution of hurricane-related activity to extreme precipitation over North America and the underlying dynamics. Here, a 25-year observational analysis of daily data shows important contributions to extreme events over large regions of North America, including a pronounced signal over northern and inland areas, with an average span of influence extending to several hundred kilometers. Over large areas of the Northeast, there are stations where more than two-thirds of all extreme events are linked to hurricane-related activity. Large-scale vertical velocity, maximum wind speed, and tropical/extratropical character are shown to be important factors in the strength and range of influence. Analysis of dynamical factors, including buoyancy, moisture availability, and lifting, show the largest changes in lifting, with rising motion typical of the deep tropics occurring over inland and northern latitudes.
Model Uncertainty and Endogenous Volatility

This paper identifies two channels through which the economy can generate endogenous inflation and output volatility, an empirical regularity, by introducing model uncertainty into a Lucas-type monetary model. The equilibrium path of inflation depends on agents’ expectations and a vector of exogenous random variables. Following Branch and Evans (2004) agents are assumed to underparameterize their forecasting models. A Misspecification Equilibrium arises when beliefs are optimal given the misspecification and predictor proportions based on relative forecast performance. We show that there may exist multiple Misspecification Equilibria, a subset of which are stable under least squares learning and dynamic predictor selection. The dual channels of least squares parameter updating and dynamic predictor selection combine to gen
On Endogenous Reconfiguration in Mobile Robotic Networks

In this paper, our focus is on certain applications for mobile robotic networks, where reconfiguration is driven by factors intrinsic to the network rather than changes in the external environment. In particular, we study a version of the coverage problem useful for surveillance applications, where the objective is to position the robots in order to minimize the average distance from a random point in a given environment to the closest robot. This problem has been well-studied for omni-directional robots and it is shown that optimal configuration for the network is a centroidal Voronoi configuration and that the coverage cost belongs to Θ(m − 1/2), where m is the number of robots in the network. In this paper, we study this problem for more realistic models of robots, namely the double integrator (DI) model and the differential drive (DD) model. We observe that the introduction of these motion constraints in the algorithm design problem gives rise to an interesting behavior. For a sparser network, the optimal algorithm for these models of robots mimics that for omni-directional robots. We propose novel algorithms whose performances are within a constant factor of the optimal asymptotically (i.e., as m → + ∞). In particular, we prove that the coverage cost for the DI and DD models of robots is of order m − 1/3. Additionally, we show that, as the network grows, these novel algorithms outperform the conventional algorithm; hence necessitating a reconfiguration in the network in order to maintain optimal quality of service.
Information and multi-sensor coordination

The control and integration of distributed, multi-sensor perceptual systems is a complex and challenging problem. The observations or opinions of different sensors are often disparate, incomparable and are usually only partial views. Sensor information is inherently uncertain, and in addition the individual sensors may themselves be in error with respect to the system as a whole. The successful operation of a multi-sensor system must account for this uncertainty and provide for the aggregation of disparate information in an intelligent and robust manner. We consider the sensors of a multi-sensor system to be members or agents of a team, able to offer opinions and bargain in group decisions. We will analyze the coordination and control of this structure using a theory of team decision making. We present some new analytic results on multi-sensor aggregation and detail a simulation which we use to investigate our ideas. This simulation provides a basis for the analysis of complex agent structures cooperating in the presence of uncertainty. The results of this study are discussed with reference to multi-sensor robot systems, distributed AI and decision making under uncertainty.
A path analysis of educator perceptions of open educational resources using the technology acceptance model

Open educational resources (OER) are making their way into a variety of educational contexts from formal lesson planning to just in time learning. Educators and training professionals have been recognized as an important audience for these materials. The concepts of self - efficacy and outcome judgment from social cognitive learning theory serve as theoretical constructs to measure educator perceptions of OER. This study uses a path analysis, based on the technology acceptance model, to understand adoption of these resources by this audience with a particular emphasis on self-efficacy. Among the participants, three main groups were identified: K-12 educators, higher education professionals, and those involved in workplace training. A discriminant function analysis found that K-12 educators stood out as finding OER relevant to improving their practice. Recommendations are made in regards to an emphasis on easy to use designs to improve application self-efficacy of OER and instructional messaging for future K-12 educators.
Why is unemployment so high in Bulgaria

The author seeks to determine the main factors behind poor labor market outcomes in Bulgaria. Unemployment in Bulgaria is high and of long duration. The accumulation of the unemployment stock has been caused by relatively high inflows into unemployment coupled with limited outflows. These features of the Bulgarian labor market are typical of other transition economies in Central Europe and exploring their sources is of broad interest. The author focuses on determinants of and constraints to job creation. He uses data on job creation and job destruction from a survey of employment in all registered firms. He finds that the source of large inflows into unemployment is intensive enterprise restructuring associated with a high pace of job reallocation. However, job creation falls short of job destruction. Three main factors account for the limited job creation and hiring, and thus for low outflows from unemployment: a) The unfriendly business environment, reflected by a low rate of new firm formation, and a relatively small, small and medium enterprise sector. b) Labor market rigidities, including excessive hiring and firing costs. c) Skill and spatial mismatches brought about by enterprise restructuring, as well as low skills and marginalization of the long-term unemployed who cannot successfully compete for new jobs. The author recommends a three pronged strategy to improve labor market performance: (1) removing bureaucratic constraints to entry and expansion of firms; (2) enhancing labor market flexibility through lowering hiring and firing costs; and (3) improving the educational system so as to equip workers with broad and portable skills.
Operational and Organizational Issues Facing Corporate Real Estate Executives and Managers

This article examines three major categories of issues facing corporate real estate executives in the future, as determined by a Delphi process survey conducted by the authors. We present areas of ...
Style Timing with Insiders

Aggregate demand by insiders predicts time-series variation in the value premium. Insider trading forecasts the value premium because insiders sell (buy) when markets—especially growth stocks—are overvalued (undervalued). This article suggests that investors can use signals from aggregate insider behavior to adjust style tilts and exploit sentiment-induced mispricing.
GraphLab: a new framework for parallel machine learning

Designing and implementing efficient, provably correct parallel machine learning (ML) algorithms is challenging. Existing high-level parallel abstractions like MapReduce are insufficiently expressive while low-level tools like MPI and Pthreads leave ML experts repeatedly solving the same design challenges. By targeting common patterns in ML, we developed GraphLab, which improves upon abstractions like MapReduce by compactly expressing asynchronous iterative algorithms with sparse computational dependencies while ensuring data consistency and achieving a high degree of parallel performance. We demonstrate the expressiveness of the GraphLab framework by designing and implementing parallel versions of belief propagation, Gibbs sampling, Co-EM, Lasso and Compressed Sensing. We show that using GraphLab we can achieve excellent parallel performance on large scale real-world problems.
Arithmetic, Zeros, and Nodal Domains on the Sphere

We obtain lower bounds for the number of nodal domains of Hecke eigenfunctions on the sphere. Assuming the generalized Lindelof hypothesis we prove that the number of nodal domains of any Hecke eigenfunction grows with the eigenvalue of the Laplacian. By a very different method, we show unconditionally that the average number of nodal domains of degree l Hecke eigenfunctions grows significantly faster than the uniform growth obtained under Lindelof.
The interaction of the Cretaceous/Tertiary Extinction Bolide with the atmosphere, ocean, and solid Earth

The mechanics of large-scale (~10-km diameter) asteroidal, cometary, and meteoroid swarm impact onto a silicate Earth covered by water and a gas layer (atmosphere) demonstrate that only ~ 15% to ~ 5% of the energy of 15 to 45 km/s bolides is taken up directly during the passage through the ocean and atmosphere, respectively. Upon impact with the Earth, ~ 10 to 10^2 times the bolide mass of water or rock can be ejected to the stratosphere: however, only ~0.1 bolide masses is in < 1 μm particles. The vaporized, melted, and (< 1 mm) solid ejecta transfer up to ~40% of their energy to the atmosphere and possibly oceanic surface water, giving rise to a short, possibly lethal (to large animals) heating pulse. The initial high-speed ejecta that lofted to and above the stratosphere early in the cratering flow is enriched in bolide material and has concentrations of extraterrestrial material in the range of those measured (0.01 to 0.2) in the Cretaceous/Tertiary (C/T) boundary layer. We suggest that the origin of the C/T boundary layer is this ejecta, which is heavily shocked and in the < l-μm range and, hence, once entrained in the stratosphere may be spread worldwide. Penetration of the atmosphere by the bolide creates a temporary hole in the atmosphere surrounded by strongly shocked air. The resultant inward and upward flow of the shocked atmosphere backward along the bolide trajectory lofts the vapor, fine-melted and solid ejecta to heights greater than 10 km. The larger, millimeter- to centimetersize, melt droplets that are lofted by this mechanism reenter the atmosphere and may represent microtektites and tektites. Sufficient impact-induced vapor, melted and comminuted silicate is ejected to stratospheric heights to markedly reduce the light levels at the Earth’s surface. The short-term effects of heating, followed by dust and possibly water-cloud deck induced worldwide cooling, provide several mechanisms to cause severe environmental stress to biota and possibly give rise to the varied and massive extinctions that occurred at the C/T boundary.
Topic models conditioned on arbitrary features with Dirichlet-multinomial regression

Although fully generative models have been successfully used to model the contents of text documents, they are often awkward to apply to combinations of text data and document metadata. In this paper we propose a Dirichlet-multinomial regression (DMR) topic model that includes a log-linear prior on document-topic distributions that is a function of observed features of the document, such as author, publication venue, references, and dates. We show that by selecting appropriate features, DMR topic models can meet or exceed the performance of several previously published topic models designed for specific data.
Identification of charge transfer transitions related to thiamin-bound intermediates on enzymes provides a plethora of signatures useful in mechanistic studies

Identification of enzyme-bound intermediates via their spectroscopic signatures, which then allows direct monitoring of the kinetic fate of these intermediates, poses a continuing challenge. As an electrophilic covalent catalyst, the thiamin diphosphate (ThDP) coenzyme forms a number of noncovalent and covalent intermediates along its reaction pathways, and multiple UV–vis and circular dichroism (CD) bands have been identified at Rutgers pertinent to several among them. These electronic transitions fall into two classes: those for which the conjugated system provides a reasonable guide to the observed λmax and others in which there is no corresponding conjugated system and the observed CD bands are best ascribed to charge transfer (CT) transitions. Herein is reported the reaction of four ThDP enzymes with alternate substrates: (a) acetyl pyruvate, its methyl ester, and fluoropyruvate, these providing the shortest side chains attached at the thiazolium C2 atom and leading to CT bands with λmax values of >3...
Formation of 2,3-Pentanedione from Lactic Acid over Supported Phosphate Catalysts

Abstract Lactic acid is converted to 2,3-pentanedione, acrylic acid, and acetaldehyde in vapor-phase reactions at 0.5 MPa over phosphate salts. Highest selectivities to 2,3-pentanedione are achieved at 280-300°C and long (2-4 sec) residence times, while selectivity to acrylic acid is best at 350°C and short residence times (0.4 sec). 2,3-Pentanedione is proposed to form by a second-order condensation in the presence of phosphate, while acrylic acid is proposed to result from elimination of water via a cyclic lactic acid-phosphate transition state.
Radial alternating TE sequence for faster fat suppression

This study describes a steady-state sequence that uses a radial k-space trajectory and alternating echo times (TEs) between even and odd k-space views. The sequence generated a single data set that was used to reconstruct images with inherent fat suppression. This fat suppression results from the fat phase variation in alternate echoes giving rise to cancellation in the central portion of k-space. This new fat-suppression method provides inherent fat suppression in half the acquisition time relative to the radial two-point Dixon method. The improvement in k-space sampling efficiency is demonstrated in phantom and clinical images, and through measured point-spread functions (PSFs). As a result, the radial alternating TE sequence offers improved temporal resolution over a radial version of the two-point Dixon sequence by requiring fewer total projections to obtain the same effective resolution in water-based tissues.
DEBROMINATION OF 8-BROMO-2'-DEOXYGUANOSINE BY METHYLENE BLUE AND VISIBLE LIGHT

Abstract Debromination of 8-bromo-2′-deoxyguanosine was accomplished in high yield under neutral conditions in aqueous methanol by irradiating with visible light in the presence of methylene blue as a sensitizer and triethylamine as an electron donor. The method can be extended for the debromination of other bromoaromatic compounds.
Dark matter signals in deflected mirage mediation

We investigate the parameter space of a specific class of model within the deflected mirage mediation (DMM) scenario. We look at neutralino properties and compute the thermal relic density as well as interaction rates with xenon direct detection experiments. We find that there are portions of the parameter space which are in line with the current WMAP constraints. Further we find that none of the investigated parameter space is in conflict with current bounds from the Xenon10 experiment and that future large‐scale liquid xenon experiments will probe a large portion of the model space.
Finite Temperature QCD Interfaces Out of Equilibrium

The properties of interfaces in non-equilibrium situations are studied by constructing a density matrix with a space-dependent temperature. The temperature gradient gives rise to new terms in the equation for the order parameter. Surface terms induced in effective actions by abrupt temperature changes provide a natural theoretical framework for understanding the occurence of both continuous and discontinuous behavior in the order parameter. Monte Carlo simulation of pure QCD shows both kinds of interfacial behavior. Perturbation theory predicts a universal profile in the high temperature phase, which can be tested by Monte Carlo simulation.
Unambiguous one-loop quantum energies of 1+1 dimensional bosonic field configurations

Abstract We calculate one-loop quantum energies in a renormalizable self-interacting theory in one spatial dimension by summing the zero-point energies of small oscillations around a classical field configuration, which need not be a solution of the classical field equations. We unambiguously implement standard perturbative renormalization using phase shifts and the Born approximation. We illustrate our method by calculating the quantum energy of a soliton/antisoliton pair as a function of their separation. This energy includes an imaginary part that gives a quantum decay rate and is associated with a level crossing in the solutions to the classical field equation in the presence of the source that maintains the soliton/antisoliton pair.
The purine path to chemotherapy

Antimetabolites of purine metabolism have found a use as anti-leukaemic, antiprotozoal and antiviral drugs, in immunosuppression and transplantation, and in gout and hyperuricemia. Their mechanisms of action are reviewed.
Numerical study of the magnetohydrodynamic spectra in Tokamaks using Galerkin's method

Abstract A computational technique is described for determining the ideal magnetohydrodynamic spectrum and its associated eigenfunctions. The method is suitable for axisymmetric toroidally confined plasmas with arbitrary cross sections. Using the special case of a long, straight, elliptical plasma column with low pressure and uniform axial current where analytic results are available, a study is made of the efficacy of two different choices of expansion functions. The use of a finite-element representation, keeping only a small number of terms, is shown to provide a good description of the system.
Aryl trifluoromethyl acetylenes

Abstract A wide variety of aryl trifluoromethyl acetylenes may be prepared in high yield by allowing CF3CCZnCl, generated from CF3CCH, to react with aryl iodides a catalytic amount of tetrakis(triphenylphosphine)-palladium.
Metabolism of cortisol by subcellular fractions of the rat liver.

Abstract The metabolism of cortisol was studied in the nuclei, mitochondria, microsomes and supernatant fractions of the rat-liver cells in the presence and absence of a TPNH-regenerating system. Under these two conditions, differences were observed in the metabolism of cortisol by the subcellular particles. The following steroids were isolated and identified: pregnane-3α,11β,17α,20β,21-pentol (β-cortol); pregnane-3α,11β,17α,21-tetrol-20-one (urocortisol); Δ 4 -pregnene-11β,17α,20β,21-tetrol-3-one (Reichstein's Substance E); Δ 4 -pregnene-11β,17α,21-triol-3,20-dione (cortisol); Δ 4 -pregnene-17α, 21-diol-3,11,20-trione (cortisone); Δ 4 -androstene-11β-ol-3,17-dione; Δ 4 -androstene-3, 11,17-trione (adrenosterone).
Electric Dipole Radiation from Spinning Dust Grains

We discuss the rotational excitation of small interstellar grains and the resulting electric dipole radiation from spinning dust. Attention is given to excitation and damping of grain rotation by collisions with neutrals, collisions with ions, "plasma drag," emission of infrared radiation, emission of electric dipole radiation, photoelectric emission, and formation of H2 on the grain surface. Electrostatic "focusing" can substantially enhance the rate of rotational excitation of grains colliding with ions. Under some conditions, "plasma drag"—due to interaction of the electric dipole moment of the grain with the electric field produced by passing ions—dominates both rotational damping and rotational excitation. Emissivities are estimated for dust in different phases of the interstellar medium, including diffuse H I clouds, warm H I, low-density photoionized gas, and cold molecular gas. Spinning dust grains could explain much, and perhaps all, of the 14-50 GHz background component recently observed by Kogut et al., de Oliveira-Costa et al., and Leitch et al. Future sensitive measurements of angular structure in the microwave sky brightness from the ground and from space should detect this emission from high-latitude H I clouds. It should be possible to detect rotational emission from small grains by ground-based pointed observations of molecular clouds, unless these grains are less abundant there than is currently believed.
A multi-disciplinary interpretation of migration: amenity capitalization in both land and labor markets.

Various disciplines have produced models to explain and predict human migration. A model is presented providing a taxonomy through which interdisciplinary insights can be synthesized. The imperfect information view emphasizes the role of wage differentials as representing arbitragible real utility differentials. The perfect information approach holds that wage and rent differentials are compensating differentials, eliminating real utility variation over space. Moreover, markets compress diverse aspects of spatial variation in welfare, otherwise difficult to quantify, into compensating wage and rent differentials. Rents tend to capitalize the variation in a host of amenities, thereby substantially reducing the need for a potential migrant to discover and weight the importance of various amenities. Empirical results are presented which support the latter equilibrium view. Amenities, as proxied by rents, are superior goods, as indicated by net movements toward high rent locations. This suggests the increasing relative importance of amenities as a determinant of migration.
Stereoselective synthesis of syn- and anti-1,3- and 1,2-dimethyl arrays via asymmetric conjugate additions

Asymmetric conjugate additions have been investigated with enantiopure N-enoyloxazolidinones for efficient construction of syn and anti-1,3-dimethyl arrays on an acyclic carbon backbone. Reactions of Yamamoto organocopper species exhibit characteristics of double asymmetric induction resulting from influences of the 4-substituted chiral auxiliary and features of side chain stereochemistry.
On non-compact Heegaard splittings

A Heegaard splitting of an open 3‐manifold is the partition of the manifold into two non-compact handlebodies which intersect on their common boundary. This paper proves several non-compact analogues of theorems about compact Heegaard splittings. The main result is a classification of Heegaard splittings of those open 3‐manifolds obtained by removing boundary components (not all of which are 2‐spheres) from a compact 3‐manifold. Also studied is the relationship between exhaustions and Heegaard splittings of eventually end-irreducible 3‐manifolds. It is shown that Heegaard splittings of end-irreducible 3‐manifolds are formed by amalgamating Heegaard splittings of boundary-irreducible compact submanifolds.