cssi/SciSciGPT-SciSciNet huggingface dataset:
A note on duality between measure and category

We show that there is no Erd6s-Sierpin'ski mapping preserving addition. Let M and JH be the ideals of meager and null subsets of 2W. Definition 1. A bijection F: 2W ' 2W is called an Erd6s-Sierpin'ski mapping if XGEX -F[X]EM and X E M 4= -F[X] E GV. Theorem 2 ([4], [1]). Assume CH. There exists an Erdds-Sierpin'ski mapping. El Since the existence of Erd6s-Sierpin'ski mapping implies that the ideals M and JH have the same cardinal characteristics, the existence of such mapping cannot be proved in ZFC. Consider the space 2W as a topological group with addition modulo 2. The following question has been attributed to Erd6s and Urbanik and to Ryll-Nardzewski: Is it consistent that there is an Erdds-Sierpin'ski mapping F such that Vx, y E 2W F(x + y) = F(x) + F(y)? The motivation for this question is the following (see [1] for more details): Definition 3. Suppose that X C 2W. We say that X E SJH (X has strong measure zero) if for every set F E M, X + F t4 2W. X E SM (X is strongly meager) if for every H E H, X + H t4 2W. An Erdds-Sierpin'ski mapping satisfying F(x + y) = F(x) + F(y) would also map strong measure zero sets onto strongly meager sets and vice versa. Consider the following statement (considered by Carlson in [3]): (p) For every set F E M there exists a set F' E M such that VX1 , x2 E 2W Ix E 2W ((2W \ F') + xi) U ((2W \ F') + X2) C (2w \F) + x. Let A* be the dual statement obtained by replacing M with Hf. Note that sp implies that SH is an ideal and Ap* implies that SM is an ideal (see remarks at the end of the paper). Theorem 4 (Carlson, [3]). ZFC FAp. Received by the editors December 17, 1997 and, in revised form, April 23, 1998. 2000 Mathematics Subject Classification. Primary 03E15. The author was partially supported by NSF grant DMS 95-05375 and the Alexander von Humboldt Foundation. (?2000 American Mathematical Society
Production Flexibility Contract Payments: Fiscal Year 1996

Using data from the United States Department of Agriculture on the Production Flexibility Contract (PFC) acres enrolled for fiscal year 1996, the authors calculated the payment rates by bushel, acre, and state. The total payments by state under the 1996 FAIR Act were also calculated. Figures given in this paper provide a comparison by state and commodity.
Creating a Cost-of-Doing-Business Index

In this paper we develop an index for comparing the cost of doing business across several metropolitan areas in the U.S. Such indices can be used as leading indicators of metropolitan economic growth. To create the index, we first identify factors that influence the change in business activity in metropolitan areas. We then create an instrument that allows us to compare the metropolitan areas on the basis of the climate that they provide for business development. We use both industry-based and pooled techniques to derive such an index. The index's variance decreases as the time horizon for which it is used increases. This is due in part to the declining influence of taxes. Although the industry-based estimates were hypothesized to be more accurate, the pooled technique facilitated statistical comparisons of the index across metropolitan areas. Based on the findings of the pooled regression, we find that automatic interpretation of higher values as denoting metropolitan areas with higher costs may often be invalid.
Retail and Food Services in Rutherford County: Current Status, Trends, and Supply/Demand Balance

This study examines the prospects for growth in Rutherford County’s retailing and food services industry. In particular, the study estimates the potential for capturing Rutherford County spending that occurs in other counties, called ‘spending leakage’, and also estimates the potential for attracting spending from households in nearby counties. The first section examines comparative demographic and income trends as the basis for retail growth in Rutherford County, followed with a review of the importance of retailing and food services as a source of jobs and income for the county. The next section overviews retail growth trends for the county and for La Vergne, Smyrna, and Murfreesboro. An analysis of the county’s retail supply and demand balance is next, with attention to retail sectors that are under-supplied in Rutherford County. The potential for capturing household spending from nearby counties is discussed next, followed with a summary of retail development currently planned for the county. A final section offers conclusions.
Giving Gossips Their Due: Information Provision in Games with Private Monitoring

The ability of a long-lived seller to maintain and profit from a good reputation may induce her to provide high quality or effort despite short-run incentives to the contrary. This incentive remains in place with private monitoring, provided that buyers share their information. However, this assumption is unrealistic in environments where information sharing is costly or the beneficiaries of a buyer’s sharing are strangers. I study a simple mechanism that induces costly information provision, and may explain such behavior in environments where the incentives are not overt. Agents who possess information may share it with the community and acquire a reputation for gossiping. Reputations function in tandem: sellers provide high effort because they face agents with reputations for information sharing, and expect the outcome of their dealings will be made public, while information holders share their information as a reputation for doing so results in higher effort from sellers.
Are gliomas preventable

Gliomas are a family of primary central nervous system tumors of variable malignancy that are derived from supporting glia (astrocytes, oligodendrocytes, ependymal cells) or their progenitors/stem cells. There are two potential strategies to prevention: preventing gliomas from forming and preventing lower-grade gliomas from developing into higher-grade gliomas. Each would lower time-dependent mortality. Each also depends on an understanding of what causes gliomas so that these factors can be modulated. In this presentation, I will discuss primary prevention, chemoprevention, and screening. I will first focus on the known chromosomal, genetic, and protein changes associated with the different histologic varieties of glioma and the environmental, hereditary, and infectious/viral factors that may promote glioma development and malignant progression. I will discuss a number of clinical scenarios that eventuate from the known genetic patterns of these tumors and the changes in genetic patterns that reflect malignant progression. The basic thinking is that if one could prevent specific gene mutations and/or deletions or gains of specific chromosomes that lead to the development of low-grade (WHO 2) gliomas, then theoretically this would reduce the occurrence of high-grade (WHO 3 and 4) gliomas and hence the almost certain death that now is the fate of most patients with these tumors. In the case of de novo WHO 3 and 4 tumors, being able to prevent or counter specific gene mutations and/or the deletion of specific chromosomes would in itself reduce the occurrence of these gliomas and increase survival. Alternatively, a curative treatment for low-grade glioma that prevents these chromosomal/gene changes would prevent some glioblastomas (WHO 4) from forming and would have the same desired effect on survival. Obviously, for the latter to be achieved, we must also be able to diagnose and treat low-grade gliomas earlier.
Organization of Disaster Aid Delivery: Spending Your Donations

AbstractThis article examines how different organizational structures in disaster aid delivery affect house aid quality. We analyze three waves of survey data on fishermen and fishing villages in Aceh, Indonesia, following the 2004 tsunami. We categorize four organizational structures based on whether and to whom donors contract aid implementation. Compared to bilateral contracting between donors and implementers, donors that vertically integrate and do their own implementation offer the highest-quality housing as rated by village heads and have fewer counts of faults, such as leaky roofs and cracked walls, as reported by fishermen. However, they shade in quality as they lose dominance as the leading aid agency in a village. Domestic implementers and the government agency that was responsible for significant portions of aid delivery provide significantly lower-quality aid. We also examine how the imposition of shared ownership, the primary social agenda for boat aid agencies, affects boat aid quality. We ...
Automated merging of software prototypes

As software becomes more complex, more sophisticated development and maintenance methods are needed to ensure software quality. Computer-aided prototyping achieves this via quickly built and iteratively updated prototypes of the intended system. This process requires automated support for keeping track of many independent changes and for exploring different combinations of alternative changes and refinements. This article formalizes the update and change merging process, extends the idea to multiple changes to the same base prototype, and introduces a new method of slicing prototypes. Applications of this technology include automatic updating of different versions of existing software with changes made to the baseline version of the system, integrating changes made by different design teams during development, and checking consistency after integration of seemingly disjoint changes to the same software system.
Harvesting of location-specific information through wifi networks

Ubiquitous computing requires ready access to information that is relevant to users' context – especially information relevant to their current location. Applications on our personal devices should be able to autonomously and continuously harvest the information provided at that location and interrupt us only when it is important to do so. Currently, client devices are designed for explicit querying for information rather than continuous background harvesting of relevant information. To enable ubiquitous access to location-specific information, we can take advantage of the widespread deployment of WiFi networks. There is a wealth of location-specific information that network providers are willing to make publicly available to any users. However, today's models for accessing wireless networks do not easily support this due primarily to concerns over security and bandwidth utilization. In this paper, we present and compare the different methods that can be applied to solve the problem of continuous background access to location-specific information. Specifically, we compare client-pull and server-push models and show how tradeoffs can be made involving privacy, power consumption on devices, and utilization of wireless bandwidth. We also present three applications and discuss how the tradeoffs affect their design.
Economic mobility in Europe and Central Asia : exploring patterns and uncovering puzzles

Substantial upward economic mobility in the majority of countries in Europe and Central Asia in the 2000s translated into achievements in reducing poverty and boosting shared prosperity. Although factors associated with upward mobility vary significantly by country, education and jobs undoubtedly play an important role in lifting households out of poverty and helping them to improve their living standards. This study finds there is a puzzling mismatch between the objective economic mobility patterns observed in survey data and people's subjective perception of their mobility. A majority of people in the region perceives they are worse off economically than in the past and voice frustration over limited opportunities to improve their lives. This disconnect is partly explained by increased inequality in the region, an increasing sense of unfairness in the processes to move up, and a more marked sense of insecurity and vulnerability. Although the region has been making headway in lifting households out of poverty, ensuring sustainable progress toward poverty reduction and shared prosperity requires policies that promote human capital accumulation, foster job creation, and offer adequate protection to improve households' resilience to shocks.
Static and Dynamic Analysis of Guy Cables

Formulas are derived and illustrated by examples; cable sag is accounted for in more exact manner than has been previously accomplished without causing additional complexity in resulting expressions; use of formulas can be extended to analysis of transmission lines and unloaded back stays for suspension bridges.
THE SIMPLE ECONOMICS OF COMMODITY PRICE SPECULATION

The price of crude oil never exceeded $40 per barrel until mid-2004. By July 2008 it peaked at $145 and by late 2008 it fell to $30 before increasing to $110 in 2011. Are speculators partly to blame for these price changes? Using a simple model of supply and demand in the cash and storage markets, we determine whether speculation is consistent with data on production, inventory changes, and convenience yields. We focus on crude oil, but our approach can be applied to other commodities. We show speculation had little, if any, effect on oil prices. (JEL G13, G18, G23, G31, Q35, Q38)
Linear relations in the Calkin algebra for composition operators

We consider this and related questions: When is a finite linear combination of composition operators, acting on the Hardy space or the standard weighted Bergman spaces on the unit disk, a compact operator?
Associations of objectively measured and self-reported sleep duration with carotid artery intima media thickness among police officers.

Background We aimed to examine the association of objectively measured and self-reported sleep duration with carotid artery intima media thickness (IMT) among 257 police officers, a group at high risk for cardiovascular disease (CVD).
Rational Approximation, Oscillatory Cauchy Integrals, and Fourier Transforms

We develop the convergence theory for a well-known method for the interpolation of functions on the real axis with rational functions. Precise new error estimates for the interpolant are derived using existing theory for trigonometric interpolants. Estimates on the Dirichlet kernel are used to derive new bounds on the associated interpolation projection operator. Error estimates are desired partially due to a recent formula of the author for the Cauchy integral of a specific class of so-called oscillatory rational functions. Thus, error bounds for the approximation of the Fourier transform and Cauchy integral of oscillatory smooth functions are determined. Finally, the behavior of the differentiation operator is discussed. The analysis here can be seen as an extension of that of Weber (Numer Math 36(2):197–209, 1980) and Weideman (Math Comput 64(210):745–745, 1995) in a modified basis used by Olver (2011) that behaves well with respect to function multiplication and differentiation.
Implementation and indeterminacy

David Chalmers has defended an account of what it is for a physical system to implement a computation. The account appeals to the idea of a "combinatorial-state automaton" or CSA. It is unclear whether Chalmers intends the CSA to be a computational model in the usual sense, or merely a convenient formalism into which instances of other models can be translated. I argue that the CSA is not a computational model in the usual sense because CSAs do not perspicuously represent algorithms, are too powerful both in that they can perform any computation in a single step and in that without so far unspecified restrictions they can "compute" the uncomputable, and are too loosely related to physical implementations.
Decoding Coalescent Hidden Markov Models in Linear Time

In many areas of computational biology, hidden Markov models HMMs have been used to model local genomic features. In particular, coalescent HMMs have been used to infer ancient population sizes, migration rates, divergence times, and other parameters such as mutation and recombination rates. As more loci, sequences, and hidden states are added to the model, however, the runtime of coalescent HMMs can quickly become prohibitive. Here we present a new algorithm for reducing the runtime of coalescent HMMs from quadratic in the number of hidden time states to linear, without making any additional approximations. Our algorithm can be incorporated into various coalescent HMMs, including the popular method PSMC for inferring variable effective population sizes. Here we implement this algorithm to speed up our demographic inference method diCal, which is equivalent to PSMC when applied to a sample of two haplotypes. We demonstrate that the linear-time method can reconstruct a population size change history more accurately than the quadratic-time method, given similar computation resources. We also apply the method to data from the 1000 Genomes project, inferring a high-resolution history of size changes in the European population.
Interstellar Grains in Meteorites: Diamond and Silicon Carbide

Well-preserved interstellar grains occur in carbonaceous chondrites. Diamond (10–100A) contains r- and p-process Xe (suggesting a supernovae connection), and appears to have formed by stellar condensation, not by interstellar shocks. SiC (mainly 0.1–1 µm) is labeled either with s-process Xe, Kr (red giant?) or with Ne 22, N 15 (nova?), and shows large isotopic variations in N (100x), C (16x), and Si (1.3x). As Si is unaffected by H, He-burning, the Si variations reflect the isotopic heterogeneity of the ISM on the scale of individual stars; the Si compositions found thus far require at least 6 separate stars.
Finite-time braiding exponents

Topological entropy of a dynamical system is an upper bound for the sum of positive Lyapunov exponents; in practice, it is strongly indicative of the presence of mixing in a subset of the domain. Topological entropy can be computed by partition methods, by estimating the maximal growth rate of material lines or other material elements, or by counting the unstable periodic orbits of the flow. All these methods require detailed knowledge of the velocity field that is not always available, for example, when ocean flows are measured using a small number of floating sensors. We propose an alternative calculation, applicable to two-dimensional flows, that uses only a sparse set of flow trajectories as its input. To represent the sparse set of trajectories, we use braids, algebraic objects that record how trajectories exchange positions with respect to a projection axis. Material curves advected by the flow are represented as simplified loop coordinates. The exponential rate at which a braid stretches loops over a finite time interval is the Finite-Time Braiding Exponent (FTBE). We study FTBEs through numerical simulations of the Aref Blinking Vortex flow, as a representative of a general class of flows having a single invariant component with positive topological entropy. The FTBEs approach the value of the topological entropy from below as the length and number of trajectories is increased; we conjecture that this result holds for a general class of ergodic, mixing systems. Furthermore, FTBEs are computed robustly with respect to the numerical time step, details of braid representation, and choice of initial conditions. We find that, in the class of systems we describe, trajectories can be re-used to form different braids, which greatly reduces the amount of data needed to assess the complexity of the flow.
Wave-Induced Motion of Bottom Sediment Particles

Theoretical analysis yields expressions for incipient motion and net velocity of single spherical bottom sediment particles under oscillatory waves; relationships are verified by experiment; prediction of equilibrium relationships between local wave characteristics, bottom slope and median particle diameter found on natural beaches.
Shining a gluon beam through quark-gluon plasma

We compute the energy density radiated by a quark undergoing circular motion in strongly coupled $\mathcal{N}=4$ supersymmetric Yang-Mills plasma. If it were in vacuum, this quark would radiate a beam of strongly coupled radiation whose angular distribution has been characterized and is very similar to that of synchrotron radiation produced by an electron in circular motion in electrodynamics. Here, we watch this beam of gluons getting quenched by the strongly coupled plasma. We find that a beam of gluons of momenta $\ensuremath{\sim}q\ensuremath{\gg}\ensuremath{\pi}T$ is attenuated rapidly, over a distance $\ensuremath{\sim}{q}^{1/3}(\ensuremath{\pi}T{)}^{\ensuremath{-}4/3}$ in a plasma with temperature $T$. As the beam propagates through the plasma at the speed of light, it sheds trailing sound waves with momenta $\ensuremath{\lesssim}\ensuremath{\pi}T$. Presumably these sound waves would thermalize in the plasma if they were not hit soon after their production by the next pulse of gluons from the lighthouselike rotating quark. At larger and larger $q$, the trailing sound wave becomes less and less prominent. The outward-going beam of gluon radiation itself shows no tendency to spread in angle or to shift toward larger wavelengths, even as it is completely attenuated. In this regard, the behavior of the beam of gluons which we analyze is reminiscent of the behavior of jets produced in heavy ion collisions at the LHC which lose a significant fraction of their energy without appreciable change in their angular distribution or their momentum distribution as they plow through the strongly coupled quark-gluon plasma produced in these collisions.
Preferential Liberalization and Its Economy-Wide Effects in Honduras

This paper quantifies the likely benefits of trade and investment liberalization in a small, poor, open economy, using the accession of Honduras to the Dominican Republic-Central American Free Trade Agreement as a case study. The results show that bilateral trade liberalization with the United States is likely to have almost no effect on welfare in Honduras, while the reciprocal removal of protection vis-a-vis the rest of Central America would lead to significantly larger gains. Potential gains from increased net foreign direct investment inflows overwhelm those expected from trade reform alone, particularly if the new foreign direct investment generates productivity spillovers. However, if it is to replace Honduran investment rather than complement domestic capital formation, growth performance is unlikely to improve and may even suffer. The paper's results identify several areas for policy attention by Honduran policy makers to make the Dominican Republic-Central American Free Trade Agreement more development-friendly. These include carefully considering the budgetary implications of trade reform, widening social safety nets to counter the trends toward increasing income inequality, and sequencing the reforms to ensure a close alignment of Honduras' comparative advantage on the regional and global markets.
History of Epidemiologic Studies

Epidemiology can be defined as the scientific method used to assess health and its determinants in populations. Central to the method are measures of disease occurrence, and study designs for identifying causes of disease and quantifying their strength as causal agents. Because epidemiological studies directly address threats to human health, their findings, when available, have received emphasis in qualitative and quantitative risk assessments. Epidemiological data have the notable strength of being based on the “right” species, “real-world” exposures, and often the full range of susceptibility. Observational data often have inherent limitations, but strategies are available to handle them. The development of radiation risk models from epidemiological studies and the use of the models in quantitative risk assessment have set a risk assessment paradigm grounded in epidemiological research. Keywords: epidemiology; dose–response; causation; models; threshold; bias; confounding; meta-analysis; pooling
Lifting the Burden: State Care of the Elderly and Labor Supply of Adult Children

We use a reform in the federal funding of care for the elderly in Norway to examine the effects of formal care expansion on the labor supply decisions of middle-aged children. We find a consistent and significant negative impact of formal care expansion on insured work absences for the adult daughters of single elderly parents. This effect is particularly strong for daughters with no siblings, who are also more likely to exceed earnings thresholds after the reform. We find no impacts of the reform on daughters’ mobility or parental health, and no effects on adult sons.
Iran: Broadcasting and Revolution

The purpose of this article is twofold: to offer certain propositions on the salient characteristics of broadcasting in the Third World, and to support these propositions through the illustrative case of Iran. The article focuses on comparisons and contrasts between the Iranian broadcasting system before and after the Islamic Revolution of 1979. The Islamic Revolution had been heir to both modern and traditional communication systems and was faced with the challenge of integrating the two. Iranian broadcasting and socio-cultural, as well as political linkages are highlighted, while attention is also paid to certain unintended broadcasting consequences. The future of the mass media and the integration of the two systems ultimately depend on the political future of the country as a whole. Given the ongoing nature of the revolutionary experiments, the article can be neither detailed nor conclusive. It does, however, offer a provocative point of departure for further investigation.
Realistic modeling of radiation transmission inspection systems

We have applied Monte Carlo particle transport methods to assess a proposed neutron transmission inspection system for checked luggage. The geometry of the system and the time, energy and angle dependence of the source have been modeled in detail. A pulsed deuteron beam incident on a thick Be target generates a neutron pulse with a very broad energy spectrum which is detected after passage through the luggage item by a plastic scintillator detector operating in current mode (as opposed to pulse counting mode). The neutron transmission as a function of time information is used to infer the densities of hydrogen, carbon, oxygen and nitrogen in the volume sampled. The measured elemental densities can be compared to signatures for explosives or other contraband. By using such computational modeling it is possible to optimize many aspects of the design of an inspection system without costly and time consuming prototyping experiments or to determine that a proposed scheme will not work. The methods applied here can be used to evaluate neutron or photon schemes based on transmission, scattering or reaction techniques. >
The need for international policy coordination: what's old, what's new, what's yet to come?

The first generation of policy coordination models was introduced some 25 years ago; it provided a rationale for policy coordination, but the gains from coordination were generally thought to be small. Now, a new generation of policy coordination models is emerging, incorporating monopolistic competition and nominal inertia. Here, we examine macroeconomic interdependence and the scope for policy coordination in a tractable second generation model with two countries and multiple sectors. Initial calibration of the model suggests that second generation models may have more scope for policy coordination than did the first. D 2004 Elsevier B.V. All rights reserved.
Will More, Better, Cheaper, and Faster Monitoring Improve Environmental Management?

Two critical problems in environmental management are a lack of primary data and the difficulty of assessing the environmental impacts of human activities. Producing the information necessary to address these twin challenges is often difficult and expensive, which impedes decisionmaking in environmental management. I focus here on the possibility of making data collection more powerful and more cost-­‐effective with a suite of analyses made tractable by emerging technology for genetic analysis. More, better, cheaper, and faster information about the planet’s living resources promises to influence a wide range of legal and policy processes—from Clean Water Act compliance and related public health initiatives, to fishery stock assessments, to NEPA compliance—and could help to make value-­‐laden resource decisions more transparent in the bargain. As gathering data becomes cheaper, we may observe downstream effects to the incentives and behaviors of public agencies. Moreover, if in the future primary data is less of a limiting factor in environmental decisionmaking, it becomes increasingly important to understand the process of developing useful knowledge from raw data, and the processes by which such information may lead to action. 1 Assistant Professor, School of Marine and Environmental Affairs, University of Washington. J.D., University of California, Berkeley, School of Law (Boalt Hall), Ph.D., Columbia University. Email: rpkelly@uw.edu. 2 Many thanks to Harry Sheiber, Holly Doremus, and other organizers and participants in the 2013 Law of the Sea Institute Conference in Berkeley, California, at which I presented a draft of the material I discuss here. Jesse Port, Kevan Yamahara, Ashley Erickson, Erin Prahler, Meredith Bennett, and Megan Mach at Stanford University’s Center for Ocean Solutions—and Philip Thomsen at the University of Copenhagen—contributed to discussions and drafts of this and related material, in particular focusing on cumulative impacts analysis. Thanks to Meg Caldwell, Larry Crowder, and Ali Boehm at Stanford and the Center for Ocean Solutions for consistent support on related scientific projects that have animated the work in this paper. Natalie Lowell and David Fluharty provided valuable editing and feedback on a later draft of this piece, which substantially improved the product. Finally, thanks to Kai Lee and Kate Wing for discussions on, and support of, early-­‐stage ideas that led down interesting alleys, literal and figurative. This work was supported in part by a grant from the David and Lucile Packard Foundation.
A modified Monte Carlo “Local Importance Function Transform” method

The Local Importance Function Transform (LIFT) method uses an approximation of the contribution transport problem to bias a forward Monte-Carlo (MC) source-detector simulation [1-3]. Local (cell-based) biasing parameters are calculated from an inexpensive deterministic adjoint solution and used to modify the physics of the forward transport simulation. In this research, we have developed a new expression for the LIFT biasing parameter, which depends on a cell-average adjoint current to scalar flux (J{sup *}/{phi}{sup *}) ratio. This biasing parameter differs significantly from the original expression, which uses adjoint cell-edge scalar fluxes to construct a finite difference estimate of the flux derivative; the resulting biasing parameters exhibit spikes in magnitude at material discontinuities, causing the original LIFT method to lose efficiency in problems with high spatial heterogeneity. The new J{sup *}/{phi}{sup *} expression, while more expensive to obtain, generates biasing parameters that vary smoothly across the spatial domain. The result is an improvement in simulation efficiency. A representative test problem has been developed and analyzed to demonstrate the advantage of the updated biasing parameter expression with regards to solution figure of merit (FOM). For reference, the two variants of the LIFT method are compared to a similar variance reduction method developed bymore » Depinay [4, 5], as well as MC with deterministic adjoint weight windows (WW). (authors)« less
High-energy short-pulse carbon dioxide lasers

Lasers for fusion application represent a special class of short-pulse generators; not only must they generate extremely short temporal pulses of high quality, but they must do this at ultra-high powers and satisfy other stringent requirements by this application. This paper presents the status of the research and development of carbon-dioxide laser systems at the Los Alamos Scientific Laboratory, vis-a-vis the fusion requirements.
ELECTRONIC STRUCTURE OF f-BLOCK COMPOUNDS

The lanthanide and actinide series differ from the more widely studied d-transition metal series in that the 4f and 5f shells are inner electrons shielded by the 5s25p6 (or 6s26p6) closed shells. The result of this shielding is that the f shell interacts much less strongly with its environment than the d-transition series. Figures 1 and 2 illustrate the radial charge density for Pr3+ and U4+. The electronic structure of an fn ion is dominated by different interactions than for the more familiar d-transition ions. In this paper we will review the methods and nomenclature used to describe the electronic structure of fn compounds.
An Overview of the Blue Gene/L System Software Organization

The Blue Gene/L supercomputer will use system-on-a-chip integration and a highly scalable cellular architecture. With 65,536 compute nodes, Blue Gene/L represents a new level of complexity for parallel system software, with specific challenges in the areas of scalability, maintenance and usability. In this paper we present our vision of a software architecture that faces up to these challenges, and the simulation framework that we have used for our experiments.
Low Frequency Radio Astronomy from the Moon

The radio sky at frequencies of several MHz and below is essentially unexplored with high angular resolution due to refraction and opacity in the Earth’s ionosphere. An interferometer array in space providing arcminute resolution images would allow a wide range of problems in solar, planetary, galactic, and extragalactic astronomy to be attacked. These include the evolution of solar and planetary radio bursts, interplanetary and interstellar scintillation, the distribution of low energy cosmic rays and diffuse ionized hydrogen in our galaxy, the determination of spectral turnover frequencies and magnetic field strengths in galactic and extragalactic radio sources, searches for “fossil” radio galaxies which are no longer detectable by high frequency surveys, and searches for new sources of coherent radio emission. In addition, it is likely that unexpected objects and emission processes will be discovered by such an instrument, as has often happened when high resolution observations first become possible in a new spectral region. The Moon can provide shielding from terrestrial interference (and from the Sun half of the time) and consequently the lunar farside surface offers an ideal site of a low frequency radio array.
The minimum rank problem over finite fields

The structure of all graphs having minimum rank at most k over a ﬁnite ﬁeld with q elements is characterized for any possible k and q. A strong connection between this characterization and polarities of projective geometries is explained. Using this connection, a few results in the minimum rank problem are derived by applying some known results from projective geometry.
Gradient estimation using stochastic computation graphs

In a variety of problems originating in supervised, unsupervised, and reinforcement learning, the loss function is defined by an expectation over a collection of random variables, which might be part of a probabilistic model or the external world. Estimating the gradient of this loss function, using samples, lies at the core of gradient-based learning algorithms for these problems. We introduce the formalism of stochastic computation graphs—directed acyclic graphs that include both deterministic functions and conditional probability distributions—and describe how to easily and automatically derive an unbiased estimator of the loss function's gradient. The resulting algorithm for computing the gradient estimator is a simple modification of the standard backpropagation algorithm. The generic scheme we propose unifies estimators derived in variety of prior work, along with variance-reduction techniques therein. It could assist researchers in developing intricate models involving a combination of stochastic and deterministic operations, enabling, for example, attention, memory, and control actions.
The centrality of electricity to ICT use in low-income countries

A growing body of literature that extols the ability of information and communication technologies (ICTs) to enhance well-being in developing countries tends to focus on long run institutional and socio-economic changes as key to driving Internet uptake. The literature, however, too often ignores one factor in discussions of ICTs' importance and employment: electricity. Overlooking the centrality of electricity to any ICT for development (ICT4D) initiative has enormous consequences; countless initiatives have failed to consider the (in)ability to power the technology that is central to such development efforts. The present article seeks to address this gap by emphasizing the primacy of electricity in ICT4D initiatives. Utilizing a unique dataset that avoids issues associated with unreliably measured and inequitably distributed grid power, we examine the drivers of Internet adoption in low-income countries. We find robust evidence that increasing the distribution of electricity within under-served countries-and thereby making electricity available to a larger proportion of the population-significantly increases the number of Internet users. Arguably, improvements in infrastructure may bring about significant changes in Internet use, even in places where advancements in education and political representation remain elusive. Updated study of drivers of internet demand in low income countries.Finds electricity distribution is an important driver of increased internet use.Uses night-light data to expand view of electricity availability to on and off grid provision.
Exploiting Context When Learning to Classify

This paper addresses the problem of classifying observations when features are context-sensitive, specifically when the testing set involves a context that is different from the training set. The paper begins with a precise definition of the problem, then general strategies are presented for enhancing the performance of classification algorithms on this type of problem. These strategies are tested on two domains. The first domain is the diagnosis of gas turbine engines. The problem is to diagnose a faulty engine in one context, such as warm weather, when the fault has previously been seen only in another context, such as cold weather. The second domain is speech recognition. The problem is to recognize words spoken by a new speaker, not represented in the training set. For both domains, exploiting context results in substantially more accurate classification.
An Open Science Platform for the Next Generation of Data

Imagine an online work environment where researchers have direct and immediate access to myriad data sources and tools and data management resources, useful throughout the research lifecycle. This is our vision for the next generation of the Dataverse Network: an Open Science Platform (OSP). For the first time, researchers would be able to seamlessly access and create primary and derived data from a variety of sources: prior research results, public data sets, harvested online data, physical instruments, private data collections, and even data from other standalone repositories. Researchers could recruit research participants and conduct research directly on the OSP, if desired, using readily available tools. Researchers could create private or shared workspaces to house data, access tools, and computation and could publish data directly on the platform or publish elsewhere with persistent, data citations on the OSP. This manuscript describes the details of an Open Science Platform and its construction. Having an Open Science Platform will especially impact the rate of new scientific discoveries and make scientific findings more credible and accountable.
Participatory design of sensing networks: strengths and challenges

Participatory design (PD) involves users in all phases of design to build systems that fit user needs while simultaneously helping users understand complex systems. We argue that traditional PD techniques can benefit participatory sensing: community-based participatory research (CBPR) projects in which complex technologies, such as sensing networks using mobile phones, are the research instruments. Based on our pilot work on CycleSense, a community-based data gathering system for bicycle commuters, we discuss the benefits and challenges of PD in participatory sensing settings, and outline a method to integrate PD into the research process.
A structured, probabilistic representation of action

When agents devise plans for execution in the real world, they face two important forms of uncertainty: they can never have complete knowledge about the state of the world, and they do not have complete control, as the effects of their actions are uncertain. While most classical planning methods avoid explicit uncertainty reasoning, we believe that uncertainty should be explicitly represented and reasoned about. We develop a probabilistic representation for states and actions, based on belief networks. We define conditional belief nets (CBNs) to capture the probabilistic dependency of the effects of an action upon the state of the world. We also use a CBN to represent the intrinsic relationships among entities in the environment, which persist from state to state. We present a simple projection algorithm to construct the belief network of the state succeeding an action, using the environment CBN model to infer indirect effects. We discuss how the qualitative aspects of belief networks and CBNs make them appropriate for the various stages of the problem solving process, from model construction to the design of planning algorithms.
New Lower Bound Formulas for Multicolored Ramsey Numbers

We give two lower bound formulas for multicolored Ramsey numbers. These formulas improve the bounds for several small multicolored Ramsey numbers.
Assessing the impact of political economy factors on rules of origin under NAFTA

Rules of origin are legitimate policy instruments to prevent trade deflection in a preferential trade agreement short of a customs union. Trade deflection takes place when a product imported into the preferential trade agreement through the member with the lowest external tariff is transhipped to a higher-tariff member, while yielding a benefit for the re-exporter. Yet, when captured by special interest groups, rules of origin can restrict trade beyond what is needed to prevent trade deflection. By how much do political economy factors account for the stringency of rules of origin? This study quantifies the impact of both determinants - those considered justifiable because they prevent trade deflection and those deemed to arise from political economy forces - on the restrictiveness of rules of origin under the North American Free Trade Agreement, approximated by a restrictiveness index. The main finding is that political economy forces, especially from the United States, raised significantly the restrictiveness of the rules of origin. Indeed, in industries where political-economy forces were strong prior to the North American Free Trade Agreement, as when the U.S. Most Favored Nation tariff was high or the revealed comparative advantage of Mexico (the United States) was strong (weak), more stringent rules of origin were introduced. Thus, stricter rules of origin are associated with higher production costs reducing the potential benefits of enhanced market access that is initially pursued by this type of agreement.
AVID: an integrative framework for discovering functional relationships among proteins

Determining the functions of uncharacterized proteins is one of the most pressing problems in the post-genomic era. Large scale protein-protein interaction assays, global mRNA expression analyses and systematic protein localization studies provide experimental information that can be used for this purpose. The data from such experiments contain many false positives and false negatives, but can be processed using computational methods to provide reliable information about protein-protein relationships and protein function. An outstanding and important goal is to predict detailed functional annotation for all uncharacterized proteins that is reliable enough to effectively guide experiments. We present AVID, a computational method that uses a multi-stage learning framework to integrate experimental results with sequence information, generating networks reflecting functional similarities among proteins. We illustrate use of the networks by making predictions of detailed Gene Ontology (GO) annotations in three categories: molecular function, biological process, and cellular component. Applied to the yeast Saccharomyces cerevisiae, AVID provides 37,451 pair-wise functional linkages between 4,191 proteins. These relationships are ~65–78% accurate, as assessed by cross-validation testing. Assignments of highly detailed functional descriptors to proteins, based on the networks, are estimated to be ~67% accurate for GO categories describing molecular function and cellular component and ~52% accurate for terms describing biological process. The predictions cover 1,490 proteins with no previous annotation in GO and also assign more detailed functions to many proteins annotated only with less descriptive terms. Predictions made by AVID are largely distinct from those made by other methods. Out of 37,451 predicted pair-wise relationships, the greatest number shared in common with another method is 3,413. AVID provides three networks reflecting functional associations among proteins. We use these networks to generate new, highly detailed functional predictions for roughly half of the yeast proteome that are reliable enough to drive targeted experimental investigations. The predictions suggest many specific, testable hypotheses. All of the data are available as downloadable files as well as through an interactive website at http://web.mit.edu/biology/keating/AVID . Thus, AVID will be a valuable resource for experimental biologists.
Do Peripheral Workers Do Peripheral Work? Comparing the Use of Highly Skilled Contractors and Regular Employees

This paper uses data from a 2002 survey of project managers in a large, U.S.-based financial services institution to compare how contractors and regular employees were assigned to work within an information technology department. The author uses these data to test standard core-periphery arguments about the use of contingent workers, as well as accounts of contingent work that emphasize the interests of frontline manag ers. He finds that contractors and employees were used very similarly in most respects, although there were some differences. Contractors were less likely to be used in roles that were more critical to the firm, but more likely to be used when frontline managers' interests could conflict with the organization's. Contractors were also less likely to be given positions requiring knowledge of the business. No evidence is found, however, that other kinds of firm-specific skills affected how contractors were used.
Fast label embeddings via randomized linear algebra

Many modern multiclass and multilabel problems are characterized by increasingly large output spaces. For these problems, label embeddings have been shown to be a useful primitive that can improve computational and statistical efficiency. In this work we utilize a correspondence between rank constrained estimation and low dimensional label embeddings that uncovers a fast label embedding algorithm which works in both the multiclass and multilabel settings. The result is a randomized algorithm whose running time is exponentially faster than naive algorithms. We demonstrate our techniques on two large-scale public datasets, from the Large Scale Hierarchical Text Challenge and the Open Directory Project, where we obtain state of the art results.