cssi/SciSciGPT-SciSciNet huggingface dataset:
Old-age benefits and retirement decisions of rural elderly in Brazil

Abstract I estimate the impact of social security benefits on retirement decisions of rural workers by studying changes in the rules governing old-age benefits for rural workers in Brazil. I focus on a reform implemented in 1991, which reduced the minimum eligibility age, increased benefits, and extended the program to non-heads of households. Because those benefits come with no strings attached — they are not means or retirement tested — any behavioral response is a pure income effect. The main finding of the paper is that access to old-age benefits is a strong determinant of retirement of rural workers in Brazil: receiving old-age benefits increases the probability of not working by about thirty-eight percentage points and reduces total hours per week by 22½ h.
Trapping and assembly of living colloids at water-water interfaces.

We study the assembly of inert and living colloids in a two-phase water–water system that provides an environment that can sustain bacteria, providing a new structure with rich potential to confine and structure microbial communities. The water–water system, formed via phase separation of a casein and xanthan mixture, forms a 3-D structure of coexisting casein-rich and xanthan-rich phases. Fluorescent labelling and confocal microscopy reveal the attachment of these living colloids, including Escherichia coli and Pseudomonas aeruginosa, at the interface between the two phases. Inert colloids also become trapped at the interfaces, suggesting that the observed attachment can be attributed to capillarity. Over time, these structures coarsen and eventually degrade, illustrating the dynamic nature of these systems. This system lays the foundation for future studies of the interplay of physicochemical properties of the fluid interfaces and bulk phases and microbial responses they provoke to induce complex spatial organization, to study species which occupy distinct niches, and to optimize efficient microbial cross-feeding or protection from competitors.
Self-Consistent Langevin Simulation of Coulomb Collisions in Charged-Particle Beams

In many plasma physics and charged-particle beam dynamics problems, Coulomb collisions are modeled by a Fokker-Planck equation. In order to incorporate these collisions, we present a three-dimensional parallel Langevin simulation method using a Particle-In-Cell (PIC) approach implemented on high-performance parallel computers. We perform, for the first time, a fully self-consistent simulation, in which the friction and diffusion coefficients are computed from first principles. We employ a two-dimensional domain decomposition approach within a message passing programming paradigm along with dynamic load balancing. Object oriented programming is used to encapsulate details of the communication syntax as well as to enhance reusability and extensibility. Performance tests on the SGI Origin 2000, IBM SP RS/6000 and the Cray T3E-900 have demonstrated good scalability. As a test example, we demonstrate the collisional relaxation to a final thermal equilibrium of a beam with an initially ansiotropic velocity distribution.
Domestic-Level Diversionary Theory of War Targeting Ethnic Minorities

According to the diversionary war theory, problematic domestic circumstances motivate a country's leader to divert popular discontent by launching a militarized international crisis. Yet, empirical...
Dynamic cities and creative clusters

The author focuses on how urban policies and the clustering of creative industries has influenced urban outcomes. The set of creative industries include those with output protectable under some form of intellectual property law. More specifically, this sub-sector encompasses software, multimedia, video games, industrial design, fashion, publishing, and research and development. The cities that form the basis for the empirical investigations are those where policy-induced transitions have been most evident, including Boston; San Francisco; San Diego; Seattle; Austin; Washington, D.C.; Dublin (Ireland); Hong Kong (China); and Bangalore (India). The key research questions are: 1) What types of cities are creative? 2) What locational factors are essential? 3) What are the common urban policy initiatives used by creative cities? The author explores the importance of the external environment for innovation and places it in the larger context of national innovation systems. Based on a study of development in Boston and San Diego, he isolates the factors and policies that have contributed to the local clustering of particular creative industries. In both cities, universities have played a major role in catalyzing the local economy by generating cutting-edge research findings, proactively collaborating with industries, and supplying the needed human capital. In addition, these two cities benefited from the existence of anchor firms and active industry associations that promoted fruitful university-industry links. Many cities in East Asia are aspiring to become the creative hubs of the region. But their investments tend to be heavily biased toward infrastructure provision. Although this is necessary, the heavy emphasis on hardware can lead to underinvestment in developing the talents and skills needed for the emergence of creative industries in these cities.
Ambiguous business cycles

This paper considers business cycle models with agents who dislike both risk and ambiguity (Knightian uncertainty). Ambiguity aversion is described by recursive multiple priors preferences that capture agents' lack of confidence in probability assessments. While modeling changes in risk typically requires higher-order approximations, changes in ambiguity in our models work like changes in conditional means. Our models thus allow for uncertainty shocks but can still be solved and estimated using first-order approximations. In our estimated medium-scale DSGE model, a loss of confidence about productivity works like `unrealized' bad news. Time-varying confidence emerges as a major source of business cycle fluctuations.
Diamond-free families

Given a finite poset P, we consider the largest size La(n,P) of a family of subsets of [n]:={1,...,n} that contains no (weak) subposet P. This problem has been studied intensively in recent years, and it is conjectured that @p(P):=lim"n"->"~La(n,P)/(n@?n2@?) exists for general posets P, and, moreover, it is an integer. For k>=2 let D"k denote the k-diamond poset {A
Application of AHP and Taguchi loss functions in evaluation of advanced manufacturing technologies

The purpose of this study is the development of a decision model to help decision makers with their technology selection. Evaluation and selection of a new technology is a multi-criteria decision making process encompassing various tangible and intangible factors. Thus, the identification of these factors and a thorough analysis of the impact, both positive and negative, on the organization should be included in the evaluation technique. Therefore, the first step is the identification of the pertinent factors. To accomplish this both risks and benefits of implementing a new technology are identified. Once pertinent risks and benefits are identified a mechanism for analysis of these factors is developed. Taguchi loss function is used to measure performance of each technology candidate with respect to the risk and benefit categories. Appropriate Taguchi loss functions are formulated based on the target value and the specification limits set by the decision maker. Analytic Hierarchy Process (AHP) is used to determine the relative importance of the risks and benefits to the decision maker. The weighted loss scores are calculated for each technology alternative by using the relative importance as the weights. The composite weighted loss scores are then calculated and used for ranking of the technology alternatives. The technology with the smallest composite loss score is recommended for adoption.
High-Capacity Tube Network Design Using the Hough Transform

A new airspace design concept, tube networks, could enable high-density operations with less air traffic control workload. To construct tubes optimally, it is necessary to identify the commonality of flight trajectories. This paper proposes a new strategy to cluster great circle flight trajectories for forming tubes. The Hough transform is applied to identify groups or clusters of great circle trajectories that could form the tube networks. The genetic algorithm is then applied to optimize the tube network. Results show that small deviations from great circle routes could yield tubes that accommodate significant traffic levels within feasible computational time.
Japanese Import Demand for U.S. Beef and Pork: Effects on U.S. Red Meat Exports and Livestock Prices

Japanese import demand for U.S. beef and pork products and the effects on domestic livestock prices are econometrically estimated. Japan is the most important export market for U.S. beef and pork products. Results indicate foreign income, exchange rates, and protectionist measures are statistically significant. The comparative statics quantify the effects of recent economic volatility. For example, the 1995-1998 depreciation in the Japanese yen (39%) reduced U.S. slaughter steer and hog prices by 0.33 per cwt, respectively. Livestock producers will continue to have a vested interest in Asian trade liberalization policies.
Emergence and evolution of patterns

We consider macroscopic systems driven away from thermodynamic equilibrium by an imposed gradient in temperature, velocity, or concentration. For a sufficiently small imposed gradient, a system will assume (asymptotically) the symmetry of the boundary conditions. However, when the imposed gradient exceeds a critical value, a system will spontaneously break the symmetry of the boundary conditions and form a spatial pattern. In two dimensions the pattern could be traveling waves (e.g., spirals) or an array of squares, stripes, or hexagons. With larger imposed gradients, the patterns can become more complex and even disordered in both space and time. We discuss the general principles of pattern formation in systems driven away from equilibrium and illustrate the principles with examples from experiments.
Optimal Designs for Rational Function Regression

We consider the problem of finding optimal nonsequential designs for a large class of regression models involving polynomials and rational functions with heteroscedastic noise also given by a polynomial or rational weight function. Since the design weights can be found easily by existing methods once the support is known, we concentrate on determining the support of the optimal design. The proposed method treats D-, E-, A-, and Φ p -optimal designs in a unified manner, and generates a polynomial whose zeros are the support points of the optimal approximate design, generalizing a number of previously known results of the same flavor. The method is based on a mathematical optimization model that can incorporate various criteria of optimality and can be solved efficiently by well-established numerical optimization methods. In contrast to optimization-based methods previously proposed for the solution of similar design problems, our method also has theoretical guarantee of its algorithmic efficiency; in conco...
The politics of ‘platforms’

Online content providers such as YouTube are carefully positioning themselves to users, clients, advertisers and policymakers, making strategic claims for what they do and do not do, and how their place in the information landscape should be understood. One term in particular, ‘platform’, reveals the contours of this discursive work. The term has been deployed in both their populist appeals and their marketing pitches, sometimes as technical ‘platforms’, sometimes as ‘platforms’ from which to speak, sometimes as ‘platforms’ of opportunity. Whatever tensions exist in serving all of these constituencies are carefully elided. The term also fits their efforts to shape information policy, where they seek protection for facilitating user expression, yet also seek limited liability for what those users say. As these providers become the curators of public discourse, we must examine the roles they aim to play, and the terms by which they hope to be judged.
Uncertainty, information and complexity in identification and control

The relationship between information acquisition (identification) and information processing (control) in their capability of dealing with uncertainty is studied. It is revealed that such a relationship can be established rigorously from the viewpoint of complexity. A notion of information-based complexity is hence introduced, first in its generality, and then in its special applications to metric spaces in feedback control systems. Copyright © 2000 John Wiley & Sons, Ltd.
The isoxazole as a linchpin for molecules that target folded DNA conformations: selective lateral lithiation and palladation

Abstract 3-(10′-Halo-9′-anthracenyl)-5-methyl-4-isoxazolecarboxylic acid ethyl esters served as a useful scaffold for highly efficient lateral metalation at the C(5), and Suzuki–Fu palladium catalyzed cross coupling at the C(10′).
Nuclear data sheets for A = 50

Abstract Nuclear structure data available through May 1976 are compiled, and adopted level properties are given. The bulk of the data are presented pictorially for easy comparison. Experimental details, references, and additional comments, where required, are given in the text. All drawings, tables, and comments are reproduced from the computerized Evaluated Nuclear Structure Data File (ENSDF). Any additions or corrections desired by the users should be addressed to the compilers for maintenance and updating of the computer file.
Linguistic support for atomic data types

The problems of concurrency and failures in distributed systems can be addressed by implementing applications in terms of atomic data types: data types whose objects provide serializability and recoverability for transactions using them. The specifications of the types can be used to permit high levels of concurrency among transactions while still ensuring atomicity. However, highly concurrent implementations can be quite complicated. In this paper we analyze the expressive power of existing proposals for language features intended to support the implementation of atomic types. We illustrate several limitations of existing proposals and propose a new approach that avoids these problems.
Landscape of kinetically trapped binary assemblies

For two-component assemblies, an inherent structure diagram (ISD) is the relationship between set inter-subunit energies and the types of kinetic traps (inherent structures) one may obtain from those energies. It has recently been shown that two-component ISDs are apportioned into regions or plateaux within which inherent structures display uniform features (e.g., stoichometries and morphologies). Interestingly, structures from one of the plateaux were also found to be robust outcomes of one type of non-equilibrium growth, which indicates the usefulness of the two-component ISD in predicting outcomes of some types of far-from-equilibrium growth. However, little is known as to how the ISD is apportioned into distinct plateaux. Also, while each plateau displays classes of structures that are morphologically distinct, little is known about the source of these distinct morphologies. This article outlines an analytic treatment of the two-component ISD and shows that the manner in which any ISD is apportioned arises from a single unitless order parameter. Additionally, the analytical framework allows for the characterization of local properties of the trapped structures within each ISD plateau. This work may prove to be useful in the design of novel classes of robust nonequilibrium assemblies.
Robust PCA Via Nonconvex Rank Approximation

Numerous applications in data mining and machinelearning require recovering a matrix of minimal rank. Robust principal component analysis (RPCA) is a generalframework for handling this kind of problems. Nuclear normbased convex surrogate of the rank function in RPCA iswidely investigated. Under certain assumptions, it can recoverthe underlying true low rank matrix with high probability. However, those assumptions may not hold in real-world applications. Since the nuclear norm approximates the rank byadding all singular values together, which is essentially a '1-norm of the singular values, the resulting approximation erroris not trivial and thus the resulting matrix estimator canbe significantly biased. To seek a closer approximation andto alleviate the above-mentioned limitations of the nuclearnorm, we propose a nonconvex rank approximation. Thisapproximation to the matrix rank is tighter than the nuclearnorm. To solve the associated nonconvex minimization problem, we develop an efficient augmented Lagrange multiplier basedoptimization algorithm. Experimental results demonstrate thatour method outperforms current state-of-the-art algorithms inboth accuracy and efficiency.
Disentangling Sources of Selection on Exonic Transcriptional Enhancers

In addition to coding for proteins, exons can also impact transcription by encoding regulatory elements such as enhancers. It has been debated whether such features confer heightened selective constraint, or evolve neutrally. We have addressed this question by developing a new approach to disentangle the sources of selection acting on exonic enhancers, in which we model the evolutionary rates of every possible substitution as a function of their effects on both protein sequence and enhancer activity. In three exonic enhancers, we found no significant association between evolutionary rates and effects on enhancer activity. This suggests that despite having biochemical activity, these exonic enhancers have no detectable selective constraint, and thus are unlikely to play a major role in protein evolution.
Beyond a series of security nets: Applying STAMP & STPA to port security

Port security is an increasing concern given the significant role of ports in global commerce and today’s increasingly complex threat environment. Current approaches to port security mirror traditional models of accident causality – ‘a series of security nets’ based on component reliability and probabilistic assumptions. Traditional port security frameworks result in isolated and inconsistent improvement strategies. Recent work in engineered safety combines the ideas of hierarchy, emergence, control and communication into a new paradigm for understanding port security as an emergent complex system property. The ‘System-Theoretic Accident Model and Process (STAMP)’ is a new model of causality based on systems and control theory. The associated analysis process – System Theoretic Process Analysis (STPA) – identifies specific technical or procedural security requirements designed to work in coordination with (and be traceable to) overall port objectives. This process yields port security design specifications that can mitigate (if not eliminate) port security vulnerabilities related to an emphasis on component reliability, lack of coordination between port security stakeholders or economic pressures endemic in the maritime industry. This article aims to demonstrate how STAMP’s broader view of causality and complexity can better address the dynamic and interactive behaviors of social, organizational and technical components of port security.
Teaching Students How to Evaluate the Reasonableness of Structural Analysis Results

AbstractJunior engineers are increasingly placing blind trust in computer generated structural analysis results, but the evaluation skills used by experienced engineers must have been learned at so...
Experience with decision support system and comfort with topic predict clinicians' responses to alerts and reminders.

Objective Clinicians at our institution typically respond to about half of the prompts they are given by the clinic’s computer decision support system (CDSS). We sought to examine factors associated with clinician response to CDSS prompts as part of a larger, ongoing quality improvement effort to optimize CDSS use. Methods We examined patient, prompt, and clinician characteristics associated with clinician response to decision support prompts from the Child Health Improvement through Computer Automation (CHICA) system. We asked pediatricians who were nonusers of CHICA to rate decision support topics as “easy” or “not easy” to discuss with patients and their guardians. We analyzed these ratings and data, from July 1, 2009 to January 29, 2013, utilizing a hierarchical regression model, to determine whether factors such as comfort with the prompt topic and the length of the user’s experience with CHICA contribute to user response rates. Results We examined 414 653 prompts from 22 260 patients. The length of time a clinician had been using CHICA was associated with an increase in their prompt response rate. Clinicians were more likely to respond to topics rated as “easy” to discuss. The position of the prompt on the page, clinician gender, and the patient’s age, race/ethnicity, and preferred language were also predictive of prompt response rate. Conclusion This study highlights several factors associated with clinician prompt response rates that could be generalized to other health information technology applications, including the clinician’s length of exposure to the CDSS, the prompt’s position on the page, and the clinician’s comfort with the prompt topic. Incorporating continuous quality improvement efforts when designing and implementing health information technology may ensure that its use is optimized.
Double-inclination probe for sizing steep fatigue cracks

Ultrasonic shear waves are used to size surface defects breaking the inaccessible side of steel plates. A probe oriented in a special double-inclination manner is used to size defects with steep fronts. The time delay in receiving defect-tip echoes is the sizing parameter. Equations correlating probe angles, defect height, and time were developed and checked experimentally. Statistical analysis was used to confirm a linear correlation between time and defect height.
Exchange bias and bistable magneto-resistance states in amorphous TbFeCo thin films

Amorphous TbFeCo thin films sputter deposited at room temperature on thermally oxidized Si substrate are found to exhibit strong perpendicular magnetic anisotropy. Atom probe tomography, scanning transmission electron microscopy, and energy dispersive X-ray spectroscopy mapping have revealed two nanoscale amorphous phases with different Tb atomic percentages distributed within the amorphous film. Exchange bias accompanied by bistable magneto-resistance states has been uncovered near room temperature by magnetization and magneto-transport measurements. The exchange anisotropy originates from the exchange interaction between the ferrimagnetic and ferromagnetic components corresponding to the two amorphous phases. This study provides a platform for exchange bias and magneto-resistance switching using single-layer amorphous ferrimagnetic thin films that require no epitaxial growth.
Use of an Accessible iPad App and Supplemental Graphics to Build Mathematics Skills: Feasibility Study Results.

IntroductionThe present study evaluated the feasibility of using an iPad application or “app” for algebra-readiness mathematics, with accompanying braille materials and accessible graphics, when us...
In Search of How People Change: Applications to Addictive Behaviors

How people intentionally change addictive behaviors with and without treatment is not well understood by behavioral scientists. This article summarizes research on self-initiated and professionally...
Basis collapse for holographic algorithms over all domain sizes

The theory of holographic algorithms introduced by Valiant represents a novel approach to achieving polynomial-time algorithms for seemingly intractable counting problems via a reduction to counting planar perfect matchings and a linear change of basis. Two fundamental parameters in holographic algorithms are the domain size and the basis size. Roughly, the domain size is the range of colors involved in the counting problem at hand (e.g. counting graph k-colorings is a problem over domain size k), while the basis size captures the dimensionality of the representation of those colors. A major open problem has been: for a given k, what is the smallest l for which any holographic algorithm for a problem over domain size k "collapses to" (can be simulated by) a holographic algorithm with basis size l? Cai and Lu showed in 2008 that over domain size 2, basis size 1 suffices, opening the door to an extensive line of work on the structural theory of holographic algorithms over the Boolean domain. Cai and Fu later showed for signatures of full rank that over domain sizes 3 and 4, basis sizes 1 and 2, respectively, suffice, and they conjectured that over domain size k there is a collapse to basis size ⌊log2 k⌋. In this work, we resolve this conjecture in the affirmative for signatures of full rank for all k.
Dominating plane triangulations

In 1996, Tarjan and Matheson proved that if G is a plane triangulated disc with n vertices, γ ( G ) ź n / 3 , where γ ( G ) denotes the domination number of G , i.e.źthe cardinality of the smallest set of vertices S such that every vertex of G is either in S or adjacent to a vertex in S . Furthermore, they conjectured that the constant 1 / 3 could be improved to 1 / 4 for a sufficiently large n . Their conjecture remains unsettled. In the present paper, it is proved that if G is a Hamiltonian plane triangulation with n vertices and minimum degree at least 4, then γ ( G ) ź max { ź 2 n / 7 ź , ź 5 n / 16 ź } . It follows immediately that if G is a 4-connected plane triangulation with n vertices, then γ ( G ) ź max { ź 2 n / 7 ź , ź 5 n / 16 ź } .
Teaching Economics and Providing Visual "Big Pictures"

Abstract. The goal of this paper is to investigate the importance of providing visual “big pictures” in the teaching of economics. The plurality and variety of concepts, variables, diagrams, and models involved in economics can be a source of confusion for many economics students. However, reviewing the existing literature on the importance of providing visual “big pictures” in the process of learning suggests that furnishing students with a visual “big picture” that illustrates the ways through which those numerous, diverse concepts are connected to each other could be an effective solution to clear up the mentioned mental chaos. As a practical example, this paper introduces a “big picture” that can be used as a good resource in intermediate macroeconomics classes. This figure presents twenty-seven commonly-discussed macroeconomic diagrams in the intermediate macroeconomics course, and gives little detail on some of these diagrams, aiming at helping students to get the whole picture at once on a single piece of paper. This macroeconomics big picture mostly focuses on the routes through which common diagrams in macroeconomics are connected to each other, and finally introduces the general macroeconomic equilibrium that is graphically derived through those connections. Keywords. Teaching of Economics, Pedagogy, Undergraduate and Graduate Teaching, Intermediate Macroeconomics, Neoclassical, and Keynesians IS/LM/AS/AD Models. JEL. A22, A23, E12, E13.
Reflected Brownian Motion in a Convex Polyhedral Cone: Tail Estimates for the Stationary Distribution

Consider a multidimensional obliquely reflected Brownian motion in the positive orthant, or, more generally, in a convex polyhedral cone. We find sufficient conditions for existence of a stationary distribution and convergence to this distribution at an exponential rate, as time goes to infinity, complementing the results of Dupuis and Williams (Ann Probab 22(2):680–702, 1994) and Atar et al. (Ann Probab 29(2):979–1000, 2001). We also prove that certain exponential moments for this distribution are finite, thus providing a tail estimate for this distribution. Finally, we apply these results to systems of rank-based competing Brownian particles, introduced in Banner et al. (Ann Appl Probab 15(4):2296–2330, 2005).
Teaching Children Thinking

Summery This paper is dedicated to the hope that someone with power to act will one day see that contemporary research on education is like the following experiment by a nineteenth‐century engineer who worked to demonstrate that engines were better than horses. This he did by hitching a 1/8 HP motor in parallel with his team of four strong stallions. After a year of statistical research he announced a significant difference. However, it was generally thought that there was a Hawthorne effect on the horses ... the purring of the motor made them pull harder. ∗This is the major part of a paper delivered to the IF1P Conference on Computer Education in Amsterdam, August 1970, and is published with kind permission of the author.
Insult to Injury: Disability, Earnings, and Divorce

This study measures the longitudinal effect of disability on earnings, marriage, and divorce. The data come from the Survey of Income and Program Participation matched to administrative data on longitudinal earnings. Using event-study methods, the results show that the onset of a work-preventing disability is associated with a precipitous decline in earnings and an increase in divorce. Consistent with theory, the association between disability and divorce is greatest among young and educated males who experience a work-preventing, rather than a work-limiting, disability.
Correlating Lagrangian structures with forcing in two-dimensional flow

Lagrangian coherent structures (LCSs) are the dominant transport barriers in unsteady, aperiodic flows, and their role in organizing mixing and transport has been well documented. However, nearly all that is known about LCSs has been gleaned from passive observations: they are computed in a post-processing step after a flow has been observed and used to understand why the mixing and transport proceeded as it did. In many applications, the ability instead to control the presence or location of LCSs via imposed forcing would be valuable. With this goal in mind, we study the relationship between LCSs and external forcing in an experimental quasi-two-dimensional weakly turbulent flow. We find that the likelihood of finding a repelling LCS at a given location is positively correlated with the mean strain rate injected at that point and negatively correlated with the mean speed, and that it is not correlated with the vorticity. We also find that mean time between successive LCSs appearing at a fixed location is related to the structure of the forcing field. Finally, we demonstrate a surprising difference in our results between LCSs computed forward and backward in time, with forward-time (repelling) LCSs showing much more correlation with the forcing than backwards-time (attracting) LCSs.
Sakharov and the nuclear test ban

‘I feel that questions of war and peace and disarmament are so crucial that they must be given absolute priority even in the most difficult circumstances.’—Andrei Sakharov, 1980
An unusual intramolecular trans -amidation.

Polyketide biosynthesis engages a series of well-timed biosynthetic operations to generate elaborate natural products from simple building blocks. Mimicry of these processes has offered practical means for total synthesis and provided a foundation for reaction discovery. We now report an unusual intramolecular trans-amidation reaction discovered while preparing stabilized probes for the study of actinorhodin biosynthesis. This rapid cyclization event offers insight into the natural cyclization process inherent to the biosynthesis of type II polyketide antibiotics.
Rapid RBE-Weighted Proton Radiation Dosimetry Risk Assessment:

Proton therapy dose is affected by relative biological effectiveness differently than X-ray therapies. The current clinically accepted weighting factor is 1.1 at all positions along the depth-dose profile. However, the relative biological effectiveness correlates with the linear energy transfer, cell or tissue type, and the dose per fraction causing variation of relative biological effectiveness along the depth-dose profile. In this article, we present a simple relative biological effectiveness-weighted treatment planning risk assessment algorithm in 2-dimensions and compare the results with those derived using the standard relative biological effectiveness of 1.1. The isodose distribution profiles for beams were accomplished using matrices that represent coplanar intersecting beams. These matrices were combined and contoured using MATLAB to achieve the distribution of dose. There are some important differences in dose distribution between the dose profiles resulting from the use of relative biological effectiveness = 1.1 and the empirically derived depth-dependent values of relative biological effectiveness. Significant hot spots of up to twice the intended dose are indicated in some beam configurations. This simple and rapid risk analysis could quickly evaluate the safety of various dose delivery schema.
Error field penetration and locking to the backward propagating wave

In this letter, we investigate error field penetration, or locking, behavior in plasmas having stable tearing modes with finite real frequencies ωr in the plasma frame. In particular, we address the fact that locking can drive a significant equilibrium flow. We show that this occurs at a velocity slightly above v=ωr/k, corresponding to the interaction with a backward propagating tearing mode in the plasma frame. Results are discussed for a few typical tearing mode regimes, including a new derivation showing that the existence of real frequencies occurs for viscoresistive tearing modes, in an analysis including the effects of pressure gradient, curvature, and parallel dynamics. The general result of locking to a finite velocity flow is applicable to a wide range of tearing mode regimes, indeed any regime where real frequencies occur.
Modeling the Overproduction of Ribosomes when Antibacterial Drugs Act on Cells

Bacteria that are subjected to ribosome-inhibiting antibiotic drugs show an interesting behavior: Although the drug slows down cell growth, it also paradoxically increases the cell's concentration of ribosomes. We combine our earlier nonlinear model of the energy-biomass balance in undrugged Escherichia coli cells with Michaelis-Menten binding of drugs that inactivate ribosomes. Predictions are in good agreement with experiments on ribosomal concentrations and synthesis rates versus drug concentrations and growth rates. The model indicates that the added drug drives the cell to overproduce ribosomes, keeping roughly constant the level of ribosomes producing ribosomal proteins, an important quantity for cell growth. The model also predicts that ribosomal production rates should increase and then decrease with added drug. This model gives insights into the driving forces in cells and suggests new experiments.
An Exact Efficiency Formula for Holographic Heat Engines

Further consideration is given to the efficiency of a class of black hole heat engines that perform mechanical work via the pdV terms present in the First Law of extended gravitational thermodynamics. It is noted that, when the engine cycle is a rectangle with sides parallel to the (p,V) axes, the efficiency can be written simply in terms of the mass of the black hole evaluated at the corners. Since an arbitrary cycle can be approximated to any desired accuracy by a tiling of rectangles, a general geometrical algorithm for computing the efficiency of such a cycle follows. A simple generalization of the algorithm renders it applicable to broader classes of heat engine, even beyond the black hole context.
Market-Based Coordination of Thermostatically Controlled Loads—Part I: A Mechanism Design Formulation

This paper focuses on the coordination of a population of thermostatically controlled loads (TCLs) with unknown parameters to achieve group objectives. The problem involves designing the device bidding and market clearing strategies to motivate self-interested users to realize efficient energy allocation subject to a peak energy constraint. This coordination problem is formulated as a mechanism design problem, and we propose a mechanism to implement the social choice function in dominant strategy equilibrium. The proposed mechanism consists of a novel bidding and clearing strategy that incorporates the internal dynamics of TCLs in the market mechanism design, and we show it can realize the team optimal solution. This paper is divided into two parts. Part I presents a mathematical formulation of the problem and develops a coordination framework using the mechanism design approach. Part II presents a learning scheme to account for the unknown load model parameters, and evaluates the proposed framework through realistic simulations.
A Human-Machine Collaborative System for Identifying Rumors on Twitter

The spread of rumors on social media, especially in time-sensitive situations such as real-world emergencies, can have harmful effects on individuals and society. In this work, we developed a human-machine collaborative system on Twitter for fast identification of rumors about real-world events. The system reduces the amount of information that users have to sift through in order to identify rumors about real-world events by several orders of magnitude.
Recommendations as treatments: debiasing learning and evaluation

Most data for evaluating and training recommender systems is subject to selection biases, either through self-selection by the users or through the actions of the recommendation system itself. In this paper, we provide a principled approach to handle selection biases by adapting models and estimation techniques from causal inference. The approach leads to unbiased performance estimators despite biased data, and to a matrix factorization method that provides substantially improved prediction performance on real-world data. We theoretically and empirically characterize the robustness of the approach, and find that it is highly practical and scalable.
On Solving Ill Conditioned Linear Systems

This paper presents the first results to combine two theoretically sound methods (spectral projection and multigrid methods) together to attack ill conditioned linear systems. Our preliminary results show that the proposed algorithm applied to a Krylov subspace method takes much fewer iterations for solving an ill conditioned problem downloaded from a popular online sparse matrix collection.
Australia’s new Free Trade Agreements with Japan and South Korea: Potential Impacts on the Resources and Agricultural Sectors and their Environmental Implications

This paper examines both economic and environmental impacts of the two new free trade agreements (FTAs) that Australia has recently negotiated with Japan and South Korea using the GTAP-E general equilibrium model. We analyse two trade policy scenarios: first a ‘Free trade scenario’ where bilateral tariffs are eliminated between Australia and Japan, and Australia and South Korea; second a ‘Green trade scenario’ where the ‘Free trade scenario’ is complemented by an environmental policy using an emissions trading scheme (ETS). The results indicate that two trade agreements enhance Australia’s trade at a modest expense on the environment. The paper illustrates that an ETS between Australia, Japan and Korea is an expensive policy to mitigate emissions arising from FTAs.
Backtracking intrusions

Analyzing intrusions today is an arduous, largely manual task because system administrators lack the information and tools needed to understand easily the sequence of steps that occurred in an attack. The goal of BackTracker is to identify automatically potential sequences of steps that occurred in an intrusion. Starting with a single detection point (e.g., a suspicious file), BackTracker identifies files and processes that could have affected that detection point and displays chains of events in a dependency graph. We use BackTracker to analyze several real attacks against computers that we set up as honeypots. In each case, BackTracker is able to highlight effectively the entry point used to gain access to the system and the sequence of steps from that entry point to the point at which we noticed the intrusion. The logging required to support BackTracker added 9% overhead in running time and generated 1.2 GB per day of log data for an operating-system intensive workload.
The Link Between Social Movements and Corporate Social Initiatives: Toward a Multi-level Theory

This article offers a first step toward a multi-level theory linking social movements to corporate social initiatives. In particular, building on the premise that social movements reflect ideologies that direct behavior inside and outside organizations, this essay identifies mechanisms by which social movements induce firms to engage with social issues. First, social movements are able to influence the expectations that key stakeholders have about firms’ social responsibility, making corporate social initiatives more attractive. Second, through conflict or collaboration, they shape firms’ reputation and legitimacy. And third, social movements’ ideologies manifest inside the corporations by triggering organizational members’ values and affecting managerial cognition. The essay contributes to the literatures on social movements and CSR, extends the understanding of how ideologies are manifested in movement-business interactions, and generates rich opportunities for future research.
Impact of Active Power Curtailment of Wind Turbines Connected to Residential Feeders for Overvoltage Prevention

Overvoltage is a major limiting factor for the integration of distributed generation in distribution systems. Among various solutions to the overvoltage problem, active power curtailment is an attractive solution since only small adjustments in the controllers are necessary for implementing this technique. Furthermore, it is activated only when needed. In wind energy systems, this can be achieved by adjusting the pitch angle of a wind turbine. The objective of this paper is to develop an active power curtailment strategy for small wind turbines to prevent overvoltage by controlling the pitch angle of the turbine blades. The required blade pitch angle was calculated by using the voltage droop method. The developed control strategy was validated by a real time simulation of a rural feeder model developed using RT-Lab software. The feeder is based upon a North American rural distribution network consisting of 96 small wind turbines of 20 kW, a 30 MVA distribution substation with an on-load tap-changing transformer, a rural feeder with 288 houses, a 120 kV/25 kV LV transformer, and rural loads. The results show the effectiveness of the method in keeping the voltage within acceptable limits and a reduction in network losses.
Compressive phase space tomography

We apply compressive sensing to retrieve mutual intensity using phase space tomography. Both simulation and experimental results show significant improvement in the recovery result.
Clinical issues in working with lesbian, gay, and bisexual clients.

This article discusses some of the key clinical issues for therapists to consider when working with lesbian, gay, and bisexual (LGB) clients. After a discussion of the biases that can influence psychotherapy, guidelines are given for conducting LGB-affirmative therapy that avoids these biases. Issue
With a little help from my friends: Global electioneering and World Bank lending

Abstract This paper investigates how World Bank lending responds to upcoming elections in borrowing countries. We find that investment project loans disburse faster when countries are aligned with the United States in the UN. Moreover, disbursement accelerates in the run-up to competitive executive elections if the government is geopolitically aligned with the U.S. but decelerates if the government is not. These disbursement patterns are consistent with global electioneering that serves U.S. foreign policy interests but jeopardizes the development effectiveness of multilateral lending.
The promise of plasmonics.

A technology that squeezes electromagnetic waves into minuscule structures may yield a new generation of superfast computer chips and ultrasensitive molecular detectors
Frequent detection of genital herpes simplex virus dna by polymerase chain reaction among pregnant women

Objective. —To investigate the prevalence and level of genital herpes simplex virus (HSV) among women at delivery. Design, Patients, and Setting. —A prospective analysis of HSV by culture and by polymerase chain reaction (PCR) of genital specimens and by HSV serologic studies in 100 asymptomatic women in labor; prospective analysis of HSV by PCR among 50 seronegative nonpregnant women at a student health center; and retrospective analysis of genital specimens for HSV by PCR from 17 HSV culture-positive women with uninfected neonates and from two HSV culture-negative women with HSV-infected neonates. All pregnant women were at a university hospital. Main Outcome Measures. —Presence of HSV by culture and levels of HSV by quantitative, type-specific PCR in cervical and vulvar specimens; HSV serologic testing by Western blot. Results. —All of the 100 asymptomatic women in labor who were studied prospectively were HSV culture negative. In nine HSV was recovered by PCR. Herpes simplex virus was recovered by PCR in one of the 50 seronegative nonpregnant women; she soon became seropositive. All 17 culture-positive women had HSV recovered by PCR. High levels of HSV DNA were obtained by PCR from the two culture-negative women with infected neonates. Among those from whom HSV was recovered by PCR, HSV DNA levels were 250 times higher from culture-positive samples than from culture-negative samples (11 571 genome equivalents vs 46 genome equivalents;P Conclusions. —The frequency of infant exposure to HSV DNA—containing secretions from HSV-seropositive mothers is about eight times higher than previously reported using HSV culture methods. High maternal levels of HSV DNA may be associated with an increased frequency of transmission of HSV to the infant. (JAMA. 1994;272:792-796)
Changes in Invasive Breast Cancer and Ductal Carcinoma In Situ Rates in Relation to the Decline in Hormone Therapy Use

Purpose To assess trends in invasive breast cancer and ductal carcinoma in situ (DCIS) incidence in association with changes in hormone therapy (HT) use in regular mammography screeners.
Simple,Chemoselective, Catalytic Olefin Isomerization

Catalytic amounts of Co(SaltBu,tBu)Cl and organosilane irreversibly isomerize terminal alkenes by one position. The same catalysts effect cycloisomerization of dienes and retrocycloisomerization of strained rings. Strong Lewis bases like amines and imidazoles, and labile functionalities like epoxides, are tolerated.
Origin of Efficiency Roll-Off in Colloidal Quantum-Dot Light-Emitting Diodes

We study the origin of efficiency roll-off (also called ``efficiency droop'') in colloidal quantum-dot light-emitting diodes through the comparison of quantum-dot (QD) electroluminescence and photoluminescence. We find that an electric-field-induced decrease in QD luminescence efficiency---and not charge leakage or QD charging (Auger recombination)---is responsible for the roll-off behavior, and use the quantum confined Stark effect to accurately predict the external quantum efficiency roll-off of QD light-emitting diodes.
Digital communications and the conduct of science. The new literacy

This essay is a personal perspective on the emergence of a new form of communication, optimistically called the 'EUGRAM'. This form is based on the convergence of economical digital communications with computer-aided facilities for file management, and protocols to facilitate the interconnection of users separated both in time and space. The EUGRAM is contrasted with the telephone, with the latter's demands on instant availability and the subjugation of the user to an almost uninterruptible stream of data. The EUGRAM is expected to increase the thoughtfulness of communication, the return of literacy in the efficient and precise use of language, and to enhance scientific discourse in many other ways.