cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of actuated boundaries on Tollmien-Schlichting waves and developed boundary layer turbulence

The potential for hydrodynamic drag reduction using small-scale actuation to influence turbulent boundary layer flow is investigated. When coupled with lab data, numerical simulations allow for the most complete understanding of the effect of various parameters on boundary layer turbulence. Two computational fluid dynamics (CFD) model sets are created in COMSOL, a multiphysics software package, to compare to experimental data and inform future research in the flowSiTTE laminar-to-turbulent flow tank. Effects on boundary layer dynamics and turbulence are studied through the implementation of an actuated boundary along the tank lid, using a standing wave to counter shear stress streaks characteristic of fully developed boundary layer turbulence. Numerical velocity data from the tank lid model are consistent with laboratory data collected with Particle Image Velocimetry (PIV). Additionally, boundary layer actuation of transitional turbulence is studied by analyzing the formation and dampening of Tollmien-Schlichting (TS) waves on a NACA 0012 airfoil. Standing wave actuation with amplitudes of 10-100μm along the airfoil is shown to reduce hydrodynamic drag by up to 15% at a wide range of frequencies. Boundary actuation delays the formation of the separation layer along the airfoil’s trailing edge – the region of flow responsible for much of the airfoil’s drag – keeping the flow attached for nearly the entire chord length and significantly reducing pressure drag.
Natural variation in a type-A response regulator confers maize chilling tolerance.

Maize (Zea mays L.) is a cold-sensitive species that often faces chilling stress, which adversely affects growth and reproduction. However, the genetic basis of low-temperature adaptation in maize remains unclear. Here, we demonstrate that natural variation in the type-A Response Regulator 1 (ZmRR1) gene leads to differences in chilling tolerance among maize inbred lines. Association analysis reveals that InDel-35 of ZmRR1, encoding a protein harboring a mitogen-activated protein kinase (MPK) phosphorylation residue, is strongly associated with chilling tolerance. ZmMPK8, a negative regulator of chilling tolerance, interacts with and phosphorylates ZmRR1 at Ser15. The deletion of a 45-bp region of ZmRR1 harboring Ser15 inhibits its degradation via the 26 S proteasome pathway by preventing its phosphorylation by ZmMPK8. Transcriptome analysis indicates that ZmRR1 positively regulates the expression of ZmDREB1 and Cellulose synthase (CesA) genes to enhance chilling tolerance. Our findings thus provide a potential genetic resource for improving chilling tolerance in maize. The genetic basis of low-temperature tolerance in maize is unclear. Here, the authors show that the type-A Response Regulator 1 (ZmRR1) and mitogen-activated protein kinase (MPK8) are positive and negative regulators of maize chilling tolerance, and ZmRR1 is phosphorylated by ZmMPK8 during cold treatment.
Obesity and the increasing odds of cesarean delivery.

BACKGROUND Knowledge of the associations between obesity and cesarean delivery (CD) is limited by previous research that does not separate the highest BMI classes. METHODS We identified 25,604 pregnancies in retrospective electronic medical records at an inner-city academic hospital between 2000 and 2015. We examined the association between BMI at pre-pregnancy and delivery, as well as gestational weight gain (GWG), and rates of CD, gestational diabetes mellitus (GD), and pregnancy-induced hypertension (PIH) using logistic regression and chi-square. RESULTS CD increased with each increase in delivery BMI class [X2 (7, N = 25,604) =151.40, p < .0001]. GD and PIH also significantly increased across each BMI class. Each increasing BMI class predicted 1.21 times greater odds of CD even after adjusting for maternal age, year of birth, GD, and PIH [OR = 1.21 (95% CI, 1.07-1.37)]. As compared with the IOM recommended GWG, less weight gain offered mitigation of CD and GD, though less than the recommended GWG for women who were obese pre-pregnancy also increased odds of preterm birth, low birth weight, and stillbirth. CONCLUSIONS Increasing BMI is associated with increasing rates of adverse obstetric outcomes. There exists a "dose-dependent" effect of BMI on CD and limiting GWG may be associated with mitigated risk for this outcome, but increased risk for offspring adverse birth outcomes.
Dividends and Investment Evidence of Heterogeneous Firm Behavior

This article investigates the relationship between dividend payouts and corporate investment. We find significant heterogeneity in the relationship across firms—heterogeneity that helps reconcile competing results in the literature. Drawing on financial filing data from Compustat, we first broadly replicate the statistically significant negative relationship estimated by Auerbach and Hassett. We show that this relationship does not hold if the variation is restricted to within-firm only. Our null results suggest a relatively precise zero estimate for the mean firm. Next, we investigate heterogeneity in the relationship between dividends and investment. Using quantile regression methods, we find that this negative relationship is concentrated at the top of dividends distribution: only firms from the seventieth percentile and above exhibit a strongly negative relationship, and it is these firms that drive the negative estimates of pooled ordinary least square regressions reported in prior work.
The extent of the market and stages of agricultural specialization

This paper provides empirical evidence of nonlinearity in the relationship between crop specialization in a village economy and the extent of the market (size of the urban market) relevant for the village. The results suggest that the portfolio of crops in a village economy becomes more diversified initially as the extent of the market increases. However, after the market size reaches a threshold, the production structure becomes specialized again. This evidence on the stages of agricultural diversification is consistent with the stages of diversification identified in the recent literature for the economy as a whole and also for the manufacturing sector. The evidence highlights the importance of improving farmers' access to markets through investment in transport infrastructure and removal of barriers to trading.
Home care reimbursement, long-term care utilization, and health outcomes

Abstract Using a substantial change in Medicare reimbursement policy to study the market for home health care, I find that the introduction of tightly binding average per-patient reimbursement caps led to a large drop in the provision of home care, particularly to the least healthy beneficiaries. This decline in home health utilization was not offset by increases in institutional long-term care or other medical care and there were no associated adverse health consequences. However, approximately one-quarter of the decline in Medicare spending was offset by increases in out-of-pocket expenditures for home health care, with the offset concentrated in higher income populations.
The Complexity Revolution and the Future of Economics

The paper considers the change in theoretical and empirical research in modern economics. This change is driven by the emergence of new theoretical approaches associated with the complexity theory and behavioral economics. The author shows that in future economists will reject some basic assumptions of neoclassical economics and adopt many different interdisciplinary approaches in order to study concrete economic problems. These gradual transformations should considerably change the structure of economic knowledge. Formal modeling will be of minor importance and will give place to more applied fields of research.
Applying Machine Learning Techniques to Rule Generation in Intelligent Tutoring Systems

The purpose of this research was to apply machine learning techniques to automate rule generation in the construction of Intelligent Tutoring Systems. By using a pair of somewhat intelligent iterative-deepening, depth-first searches, we were able to generate production rules from a set of marked examples and domain background knowledge. Such production rules required independent searches for both the “if” and “then” portion of the rule. This automated rule generation allows generalized rules with a small number of sub-operations to be generated in a reasonable amount of time, and provides non-programmer domain experts with a tool for developing Intelligent Tutoring Systems.
Explorations in the Economics of Intertemporal Asset Transfer in Roman Palestine

Following the Jewish Revolt and the destruction of the Jewish Temple in 70 CE, there were largescale destabilizations of the Jewish population in Palestine. Information regarding economic decisions has always been available indirectly from Jewish and Roman legalistic material, but it has been insufficiently mined for economic insights. Furthermore, over the last forty years, new documentary material has become available from the second century. This note discusses some interesting aspects of how people managed to transfer resources over time in those turbulent times. Specifically, I look at two cases of asset transfer where the primary purpose was to transfer wealth over time. I explore the role of market frictions in both cases and make comparisons to present-day circumstances.
Synthesis and Antimicrobial Activities of N4-(2-Acetoxyethoxymethyl)thiosemicarbazones and N3-(2-Acetoxyethoxymethyl)thioureas

A series of thiosemicarbazones and thioureas having an open-chain analogue of the ribosyl group, the 2-acetoxyethoxymethyl moiety, has been synthesized. Significant growth inhibitory activity versus gram-positive and gram-negative organisms, a yeast, and a mold has been found with the 2-acetoxyethoxymethyl derivatives of N-alkyl-aryl-, and heteroaryl-thiosemicarbazones and thioureas. The molecules may function as inhibitors of ribonucleotide reductase or in utilization of the carbamyl group in pyrimidine biosynthesis.
Block bootstrap consistency under weak assumptions

This paper weakens the size and moment conditions needed for typical block bootstrap methods (i.e., the moving blocks, circular blocks, and stationary bootstraps) to be valid for the sample mean of Near-Epoch-Dependent (NED) functions of mixing processes; they are consistent under the weakest conditions that ensure the original NED process obeys a central limit theorem (CLT), established by De Jong (1997, Econometric Theory 13(3), 353–367). In doing so, this paper extends De Jong’s method of proof, a blocking argument, to hold with random and unequal block lengths. This paper also proves that bootstrapped partial sums satisfy a functional CLT (FCLT) under the same conditions.
Reflecting on Fifty Years of Progress for Women in Science

L ike young women today, 50 years ago I too assumed that gender discrimination in science was a thing of the past. Girls who grew up in America in the Sputnik era, as I did, were encouraged to become scientists. By 1964, when I graduated from college with a major in biology, I thought it entirely possible I’d win a Nobel prize. Why not? Dorothy Hodgkin won one that year. At Harvard, my professors had strongly encouraged me to go to graduate school. When I finished my postdoc in 1973, I was actively recruited to the MIT faculty. What were those feminists complaining about? I would have understood had I known that 50 years ago it was almost impossible for a woman to get a faculty job in any American research university, and that it would take civil rights legislation in the mid ’60s and early ’70s to make it possible. Following is a brief account of how I came slowly to comprehend that gender bias did (and still does) exist in science, and how, starting in 1994, I worked with other women faculty and with the MIT administration to understand and mitigate its effects, with outcomes none of us could have imagined. Progress for women in academic science has been remarkable over the past half century, though equality remains elusive in all universities because of persistent societal, unconscious, and institutional gender biases.
Review of Administrative and Expert Monitoring of International Treaties, edited by Paul C. Szasz

Book review of Administrative and Expert Monitoring of International Treaties, edited by Paul C. Szasz.
Similarities and differences between one-sided and two-sided linear prediction

Provides a comparison between one-sided linear prediction (OSP) and two-sided linear prediction (TSP) with respect to prediction error, relationships to AR modeling and to two-sided AR modeling, and the application to time series interpolation, linear-phase filter design, and spectral estimation. New contributions of the paper include: (1) proof that TSP produces smaller, non-white residuals than OSP, extending previous results; (2) specification of the frequency-domain error criterion minimized by TSP, and comparison with the analogous OSP criterion; (3) demonstration that TSP and two-sided AR modeling are different problems, unlike OSP; (4) interpretation of performance of TSP interference-rejection filters.
Automated generation of tracking plans for a network of communications antennas

This paper describes the Deep Space Network Antenna Operations Planner (DPLAN) : a system that automatically generates antenna tracking plans for a set of highly sensitive radio science and telecommunications antennas. DPLAN accepts as input an equipment configuration and a set of requested antenna track services. The system then uses a knowledge base of antenna operations procedures to produce a plan of activities that will provide the requested services using the allocated equipment. DPLAN produces this plan using an integration of hierarchical task network (HTN) and operator-based planning. A prototype of the DPLAN system was successfully demonstrated in February 1995 at NASA's experimental DSN station, DSS-13, on a series of Voyager tracks. Based on this successful demonstration, DPLAN is being considered for inclusion in the larger Network Monitor and Control (NMC) upgrade underway projected to save NASA over $9 million per year in operations costs.
Tutorial: Using TPS for Higher-Order Theorem Proving and ETPS for Teaching Logic

TPS is an automated theorem proving system which can be used to prove theorems of first- or higher-order logic automatically, interactively, or in a combination of these modes of operation. Proofs in TPS are presented in natural deduction style. ETPS is a program which was obtained from TPS by deleting all the facilities for proving theorems automatically. ETPS can be used by students to learn how to prove theorems interactively. The objective of the tutorial is to teach participants how to make effective use of TPS and ETPS.
Pasteur's Quadrant and malnutrition

Basic science has been the wellspring of advances in technology in everything from cellular phones to nutrient-fortified foods. Biochemistry and food technology afford new techniques that enrich nutritional science and aid in the fight against malnutrition. Bionutrition, the term used to describe the application of these techniques, can be the source of innovations that will help eradicate malnutrition globally. Which areas of bionutrition research are most likely to yield tomorrow's breakthroughs?
Hidden Variables or Positive Probabilities

Despite claims that Bell's inequalities are based on the Einstein locality condition, or equivalent, all derivations make an identical mathematical assumption that local hidden-variable theories produce a set of positive-definite probabilities for detecting a particle with a given spin orientation. The standard argument is that because quantum mechanics assumes that particles are emitted in a superposition of states the theory cannot produce such a set of probabilites. We examine a paper by Eberhard, and several similar papers, which claim to show that a generalized Bell inequality, the CHSH inequality, can be derived solely on the basis of the locality condition, without recourse to hidden variables. We point out that these authors nonetheless assumes a set of positive-definite probabilities, which supports the claim that hidden variables or “locality” is not at issue here, positive-definite probabilities are. We demonstrate that quantum mechanics does predict a set of probabilities that violate the CHSH inequality; however these probabilities are not positive-definite. Nevertheless, they are physically meaningful in that they give the usual quantum-mechanical predictions in physical situations. We discuss in what sense our results are related to the Wigner distribution.
Hahn-Banach operators

We consider real spaces only. Definition. An operator T : X → Y between Banach spaces X and Y is called a Hahn-Banach operator if for every isometric embedding of the space X into a Banach space Z there exists a norm-preserving extension T of T to Z. A geometric property of Hahn-Banach operators of finite rank acting between finite-dimensional normed spaces is found. This property is used to characterize pairs of finite-dimensional normed spaces (X, Y ) such that there exists a Hahn-Banach operator T : X → Y of rank k. The latter result is a generalization of a recent result due to B. L. Chalmers and B. Shekhtman. Everywhere in this paper we consider only real linear spaces. Our starting point is the classical Hahn-Banach theorem ([H], [B1]). The form of the Hahn-Banach theorem we are interested in can be stated in the following way. Hahn-Banach Theorem. Let X and Y be Banach spaces, T : X → Y a bounded linear operator of rank 1 and Z a Banach space containing X as a subspace. Then there exists a bounded linear operator T : Z → Y satisfying (a) ||T || = ||T ||; (b) T x = Tx for every x ∈ X. Definition 1. An operator T : Z → Y satisfying (a) and (b) for a bounded linear operator T : X → Y is called a norm-preserving extension of T to Z. The Hahn-Banach theorem is one of the basic principles of linear analysis. It is quite natural that there exists a vast literature on generalizations of the HahnBanach theorem for operators of higher rank. See papers by G. P. Akilov [A], J. M. Borwein [Bor], B. L. Chalmers and B. Shekhtman [CS], G. Elliott and I. Halperin [EH], D. B. Goodner [Go], A. D. Ioffe [I], S. Kakutani [Kak], J. L. Kelley [Kel], J. Lindenstrauss [L1], [L2], L. Nachbin [N1] and M. I. Ostrovskii [O], representing different directions of such generalizations, and references therein. There exist two interesting surveys devoted to the Hahn-Banach theorem and its generalizations; see G. Buskes [Bus] and L. Nachbin [N2]. We shall use the following natural definition. Definition 2. An operator T : X → Y between Banach spaces X and Y is called a Hahn-Banach operator if for every isometric embedding of the space X into a Banach space Z there exists a norm-preserving extension T of T to Z. Received by the editors February 9, 2000. 2000 Mathematics Subject Classification. Primary 46B20, 47A20.
Wildfire hazards: an analysis of duration, cost and size

Wildfires are managed in a complex dynamic environment where suppression effort, environmental, and geographic characteristics all influence wildfire outcomes. Suppression effort is largely driven by threats to values at risk. We develop a stochastic dynamic programming model of wildfire suppression to show that under certain conditions, suppression effort may be diverted from overall containment in order to protect specific values at risk. We then estimate a trivariate hazard model to determine the impact of threatened structures on three important wildfire outcomes: wildfire duration, size, and suppression costs. Our results suggest that expected wildfire duration and size increase when residential structures and outbuildings become threatened.
The Virtues and Limits of Codes in Legal Ethics

In the absence of codified standards of ethics, the ethical quality of law practice would degenerate into inconsistency and unpredictability. The presence of an ethics code can unduly burden and limit the practice of law. However, ethics codes should not be thought of as tools to ensure the law is practiced humanely. Instead, they should be viewed as attempts to ameliorate the impediments to a humane practice and to call lawyers to that goal.Tom Schaffer, a scholar and professor of Ethics at Notre Dame, lamented the fact that the codification of standards of attorney conduct could induce lawyers to abdicate moral responsibility. Codified rules of attorney ethics, however, are not entirely devoid of merit. Modern codes of ethics protect clients, ensuring a minimum level of performance in handling client affairs. They also ensure equality with respect to the treatment afforded each client, promote ethical discourse, and serve as symbolic declarations of principles.Though there exists the potential to affect a lot of good by ways of codified ethics rule, there are limitations, as simple rules are often insufficient to deal with complex situations and complex rules are hard to communicate, remember, or enforce. While ethic codes hold great potential for achieving important goals within the legal profession, they also suffer significant limitations, requiring the identification of a method to use codes of ethics in a way that maximized the former and minimizes the lesser.
Aggressive Outpatient treatment of Ovarian Hyperstimulation Syndrome with ascites using transvaginal culdocentesis and intravenous albumin minimizes hospitalization

Purpose: To assess the effectiveness of outpatient treatment of Ovarian Hyperstimulation Syndrome associated with ascites. Methods: Forty-eight patients diagnosed with ovarian hyperstimulation and ascites from 2246 consecutive in vitro fertilization cycles were retrospectively studied. Patients were treated with outpatient transvaginal culdocentesis and rehydration with intravenous crystalloids and albumin every 1–3 days until resolution of symptoms or hospitalization was required. Outcomes measured included incidences of hospitalization, pregnancy outcomes, cycle characteristics, and oocyte donors versus nondonors comparisons. Results: No complications occurred from outpatient treatments, and 91.6% of patients avoided hospitalization. The pregnancy rate in patients undergoing transfer was 84.7%, and the spontaneous loss rate was 16%. Overall, the estradiol on day of hCG was 4331 pg/mL (range 2211–8167), ascites removed was 1910 cm3 (122–4000), and number of outpatient treatments was 3.4 (1–14). Nondonors averaged more outpatient treatments than donors (3.97 vs. 1.85), but similar rates of hospitalization (3/35 vs. 1/13). Conclusions: Outpatient treatment consisting of culdocentesis, intravenous rehydration, and albumin minimized the need for hospitalization in hyperstimulated patients.
Can investments in emerging markets help to solve the aging problem

Prefunding of pension commitments in OECD (Organization of Economic Cooperation and Development) economies is increasingly seen as a central strategy to cope with the aging of their populations. This paper argues that investments in emerging markets can help at the margin but are unable to solve the demographic problem. While these investments bring potential advantages through enhanced risk diversification, higher rates of return, and accelerated financial market development, the total effects are likely to be limited. Furthermore, in order to harvest them, capital-sending and -receiving countries must fulfill various politically and economically challenging requirements. For pension policy, the limited contribution of pre-funding at home and abroad in order to address the demographic problem implies that enhanced emphasis must be given to domestic reforms.
A Nonparametric Model of Frontiers

In this paper we propose a nonparametric regression frontier model that assumes no specific parametric family of densities for the unobserved stochastic component that represents efficiency in the model. Nonparametric estimation of the regression frontier is obtained using a local linear estimator that is shown to be consistent and $\sqrt{nh_n}$ asymptotically normal under standard assumptions. The estimator we propose envelops the data but is not inherently biased as Free Disposal Hull - FDH or Data Envelopment Analysis - DEA estimators. It is also more robust to extreme values than the aforementioned estimators. A Monte Carlo study is performed to provide preliminary evidence on the estimator's finite sample properties and to compare its performance to a bias corrected FDH estimato
Efficient Learning of Domain-invariant Image Representations

Abstract: We present an algorithm that learns representations which explicitly compensate for domain mismatch and which can be efficiently realized as linear classifiers. Specifically, we form a linear transformation that maps features from the target (test) domain to the source (training) domain as part of training the classifier. We optimize both the transformation and classifier parameters jointly, and introduce an efficient cost function based on misclassification loss. Our method combines several features previously unavailable in a single algorithm: multi-class adaptation through representation learning, ability to map across heterogeneous feature spaces, and scalability to large datasets. We present experiments on several image datasets that demonstrate improved accuracy and computational advantages compared to previous approaches.
Life During Growth

A remarkable diversity of indicators shows quality of life across nations to be positively associated with per capita income. At the same time, the changes in quality of life as income grows are surprisingly uneven. Either in levels or changes, moreover, the effect of exogenous shifts over time is surprisingly strong compared to growth effects. This article reaches this conclusion with a panel dataset of 81 indicators covering up to four time periods (1960, 1970, 1980, and 1990). The indicators cover seven subjects: (1) individual rights and democracy, (2) political instability and war, (3) education, (4) health, (5) transport and communications, (6) inequality across class and gender, and (7) “bads.” With a SUR estimator in levels, income per capita has an impact on the quality of life that is significant, positive, and more important than exogenous shifts for 32 out of 81 indicators. With a fixed-effects estimator, growth has an impact on the quality of life that is significant, positive, and more important than exogenous shifts for 10 out of 81 indicators. With a first-differences IV estimator, growth has a causal impact on the quality of life that is significant, positive, and more important than exogenous shifts for six out of 69 quality of life indicators. The conclusion speculates about such explanations for the pattern of results as (1) the long and variable lags that may come between growth and changes in the quality of life and (2) the possibility that global socioeconomic progress is more important that home-country growth for many quality-of-life indicators.
Safe Datalog Queries with Linear Constraints

In this paper we consider Datalog queries with linear constraints. We identify several syntactical subcases of Datalog queries with linear constraints, called safe queries, and show that the least model of safe Datalog queries with linear constraints can be evaluated bottom-up in closed-form. These subcases include Datalog with only positive and upper-bound or only negative and lower bound constraints or only half-addition, upper and lower bound constraints. We also study other subcases where the recognition problem is decidable.
Co-elementary Equivalence, Co-elementary Maps, and Generalized Arcs

By a generalized arc we mean a continuum with exactly two non-separating points; an arc is a metrizable generalized arc. It is well known that any two arcs are homeomorphic (to the real closed unit interval); we show that any two generalized arcs are co-elementarily equivalent, and that co-elementary images of generalized arcs are generalized arcs. We also show that if f : X → Y is a function between compacta and if X is an arc, then f is a co-elementary map if and only if Y is an arc and f is a monotone continuous surjection.
Globalization and systemic risk

The impact of globalization of financial markets is a highly debated topic, particularly in recent months when the issue of globalization and contagion of financial distress has become a focus of intense policy debate. The papers in this volume provide an up-to-date overview of the key issues in this debate. While most of the contributions were prepared after the initial outbreak of the current global turmoil and financial crisis, they identify the relative strengths of the risk diversification and risk transmission processes and examine the empirical evidence to date. The book considers the relative roles of banks, nonbank financial institutions and capital markets in both risk diversification and risk transmission. It then evaluates the current status of crisis resolution in a global context, and speculates where to go from here in terms of understanding, resolution, prevention and public policy.
Intensive Reflection in Teacher Training: What is it Good For?

The merits of reflective exercises in teacher training are well known. Reflection through journals, surveys/questionnaires, action research, or supervised teaching and classroom discussion creates opportunities for teachers in training to think critically of what they do in their classes, why they do it, and how they could improve. Sometimes, however, teacher training programs may not be ideally positioned to offer novice student teachers (NSTs) the most extensive and coordinated opportunities for teaching, observation, and reflection. The current study examines the usefulness of an intensive reflective exercise realized as a two-question questionnaire used in a Second Language Writing (SLW) course. The findings indicate that the questionnaire was useful in eliciting a fair amount of critical thinking and integration of prior knowledge, new content, and personal experience. For the teacher trainer, it worked as a tool for assessing student learning and planning lessons. The study reflects on the limitations of the intensive reflection exercise applied in it (such as brevity and isolation from other assignments), and makes pedagogical recommendations for future implementation.
Attack Analysis and Detection for Ad Hoc Routing Protocols

Attack analysis is a challenging problem, especially in emerging environments where there are few known attack cases. One such new environment is the Mobile Ad hoc Network (MANET). In this paper, we present a systematic approach to analyze attacks. We introduce the concept of basic events. An attack can be decomposed into certain combinations of basic events. We then define a taxonomy of anomalous basic events by analyzing the basic security goals.
Internal Pressure Testing of Structural Ceramic Tubes

The U.S. Army Research Laboratory is currently investigating several candidate ceramic materials for use as the bore material for advanced gun barrels. Extensive characterization of the thermal and mechanical properties of these materials is underway using primarily standardized test procedures. For verification of modeling efforts and probabilistic strength predictions, the materials are also being tested via internal pressurization to rupture. The approach to this test is to compress an elastic material and allow the Poisson's expansion to pressurize the tube. The expression for calculating the pressure will be detailed, along with experimental verification on a control sample. The procedure has yielded pressures in excess of 240 MPa (35 ksi), which is not the limit of the fixture but is the maximum rupture pressure achieved prior to failure of the sample. The rupture pressures and maximum stress level will be reported for each of the following materials: Al 2 O 3 (ALOX), ZrO 2 (ZR02), SiC (SCEH, SCLH, and SC46), Si 3 N 4 (SN47 and SN5P), and SiAlON. An attractive feature of this methodology is that during failure, the ceramic pieces are not propelled by high pressure gases or fluids, so the parts can be collected for post-mortem analysis and fractography. Where possible, fractography will be performed and statistical analysis of the results will be presented.
Tasquinimod targets suppressive myeloid cells in the tumor microenvironment

Infiltrating myeloid derived suppressor cells and tumor-associated macrophages (TAMs) are important components of the immunosuppressive tumor microenvironment. We recently reported that tasquinimod, which binds to S100A9, impairs both infiltration and function of these cells. Here we discuss the underlying mechanisms responsible for targeting multiple suppressive populations and the modulation of the tumor microenvironment.
The financial crisis and the well-being of Americans

The Great Recession was associated with large changes in income, wealth, and unemployment, changes that affected many lives. Since January 2008, the Gallup Organization has been collecting daily data on 1,000 Americans each day, with a range of self-reported well-being (SWB) questions. I use these data to examine how the recession affected the emotional and evaluative lives of the population, as well as of subgroups within it. In the fall of 2008, around the time of the collapse of Lehman Brothers, and lasting into the spring of 2009, at the bottom of the stock market, Americans reported sharp declines in their life evaluation, sharp increases in worry and stress, and declines in positive affect. By the end of 2010, in spite of continuing high unemployment, these measures had largely recovered, though worry remained higher and life evaluation lower than in January 2008. The SWB measures do a much better job of monitoring short-run levels of anxiety as the crisis unfolded than they do of reflecting the evolution of the economy over a year or two. Even large macroeconomic shocks to income and unemployment can be expected to produce only small and hard to detect effects on SWB measures. SWB, particularly evaluation of life as a whole, is sensitive to question order effects. Asking political questions before the life evaluation question reduces reported life evaluation by an amount that dwarfs the effects of even the worst of the crisis; these order effects persist deep into the interview, and condition the reporting of hedonic experience and of satisfaction with standard of living. Methods for controlling these effects need to be developed and tested if national measures are to be comparable over space and time.
RAYLEIGH-TAYLOR INSTABILITY AND RESULTING FAILURE MODES OF ABLATIVELY IMPLODED INERTIAL FUSION TARGETS

The ablation process is thought to be useful for driving the spherical implosion of inertial confinement fusion (ICF) targets1. By “ablation” is meant the process of applying pressure continuously in time to a surface by heating the surface. The pressure applied may be thought of as the reaction to acceleration of heated material away from the surface. In fact, an implosion is only “ablative” if the time scale required for establishment of the outward flow from the surface is short compared to the implosion time; i.e., if the ablative flow is quasistationary. If the spherical target pellet is a shell of initial thickness Δrp and radius rp which is hollow or contains a much lower density fuel, then this shell, whose initial aspect ratio is defined as Ap = rp/Δrp, will accelerate inwardly. This acceleration causes the outside surface of the shell to experience instability of the Rayleigh-Taylor type, which is thought to be potentially troublesome for Ap ≳ 52. Subsequently, as the implosion of the shell is decelerated by compression of lower density fuel material inside, the inside surface becomes unstable . This article presents a theory of these instabilities and potential modes of failure caused by them.
THEORY OF THE AC RESPONSE OF ROUGH INTERFACES

It has been known for six decades that the small signal ac impedance of the interface between a blocking electrode and an aqueous or solid electrolyte frequently contains a constant-phase-angle (CPA) element whose impedance has the frequency dependence according to Z ∝ (jω)−η, where 0 < η < 1. In recent years it has been shown experimentally that the exponent η is related to the roughness of the interface, with η approaching 1 when the interface is made increasingly smooth. We propose that the CPA originates from the fractal geometry of the rough interface, and derive on the basis of a number of models that η = 3 - ds, where ds is the fractal dimension of the interface.
The Cosmic Microwave Background Radiation-A Unique Window on the Early Universe

The cosmic microwave background radiation is the remnant heat from the Big Bang. It provides us with a unique probe of conditions in the early universe, long before any organized structures had yet formed. The anisotropy in the radiation's brightness yields important clues about primordial structure and additionally provides a wealth of information about the physics of the early universe. Within the framework of inflationary dark matter models, observations of the anisotropy on sub-degree angular scales reveals the signatures of acoustic oscillations of the photon-baryon fluid at a redshift of approximately 1100. Data from the first five years of operation of the Wilkinson Microwave Anisotropy Probe (WMAP) satellite provide detailed full-sky maps of the cosmic microwave background temperature and polarization anisotropy. Together, the data provide a wealth of cosmological information, including the age of the universe, the epoch when the first stars formed, and the overall composition of baryonic matter, dark matter, and dark energy. The results also provide constraints on the period of inflationary expansion in the very first moments of time. WMAP, part of NASA's Explorers program, was launched on June 30, 2001. The WMAP satellite was produced in a partnership between the Goddard Space Flight Center and Princeton University. The WMAP team also includes researchers at the Johns Hopkins University; the Canadian Institute of Theoretical Astrophysics; University of Texas; Oxford University; University of Chicago; Brown University; University of British Columbia; and University of California, Los Angeles.
DR-CAFTA and the environment

The Dominican Republic-Central American Free Trade Agreement with the United States aims to create a free trade zone for economic development. The Agreement is expected to intensify commerce and investment among the participating countries. This paper analyzes the changes in the production and trading patterns in 2-digit manufacturing sectors with the goal of understanding the short-term environmental implications of the Dominican Republic-Central American Free Trade Agreement. More specifically, the paper addresses the questions: Did pollution increase in the period after the Agreement negotiations? Did trade and production shift toward pollution intensive factors? The results suggest an increase in pollution emissions in the post-negotiations period. The increase in emissions is mainly attributable to scale effects. Composition effects are small and in some cases (including Nicaragua and Honduras) favoring cleaner industries and partially compensating the pollution gains from output and export growth.
Reasoning under uncertainty: some Monte Carlo results

A series of monte carlo studies were performed to compare the behavior of some alternative procedures for reasoning under uncertainty. The behavior of several Bayesian, linear model and default reasoning procedures were examined in the context of increasing levels of calibration error. The most interesting result is that Bayesian procedures tended to output more extreme posterior belief values (posterior beliefs near 0.0 or 1.0) than other techniques, but the linear models were relatively less likely to output strong support for an erroneous conclusion. Also, accounting for the probabilistic dependencies between evidence items was important for both Bayesian and linear updating procedures.
Woody plant encroachment paradox: Rivers rebound as degraded grasslands convert to woodlands

[1] The related phenomena of degradation and woody plant encroachment have transformed huge tracts of rangelands. Woody encroachment is assumed to reduce groundwater recharge and streamflow. We analyzed the long-term (85 years) trends of four major river basins in the Edwards Plateau region of Texas. This region, in which springs are abundant because of the karst geology, has undergone degradation and woody encroachment. We found that, contrary to widespread perceptions, streamflows have not been declining. The contribution of baseflow has doubled—even though woody cover has expanded and rainfall amounts have remained constant. We attribute this increase in springflow to a landscape recovery that has taken place concurrently with woody expansion—a recovery brought about by lower grazing pressure. Our results indicate that for drylands where the geology supports springs, it is degradation and not woody encroachment that leads to regional-scale declines in groundwater recharge and streamflows.
Physical properties of iron in the inner core

The Earth's inner core plays a vital role in the dynamics of our planet and is itself strongly exposed to dynamic processes as evidenced by a complex pattern of elastic structure. To gain deeper insight into the nature of these processes we rely on a characterization of the physical properties of the inner core which axe governed by the material physics of its main constituent, iron. Here we review recent research on structure and dynamics of the inner core, focusing on advances in mineral physics. We will discuss results on core composition, crystalline structure, temperature, and various aspects of elasticity. Based on recent computational results, we will show that aggregate seismic properties of the inner core can be explained by temperature and compression effects on the elasticity of pure iron, and use single crystal anisotropy to develop a speculative textural model of the inner core that can explain major aspects of inner core anisotropy.
Marginal Stability of d -Wave Superconductor: Spontaneous P and T Violation in the Presence of Magnetic Impurities

We argue that the d x 2−y2-wave superconductor is marginally stable in the presence of external perturbations. Subjected to the external perturbations by magnetic impurities, it develops a secondary component of the gap, complex dxy, to maximize the coupling to impurities and lower the total energy. The secondary dxy component exists at high temperatures and produces the full gap ∼20 Kin the single particle spectrum around each impurity apart from impurity-induced broadening. At low temperatures, the phase-ordering transition into global d x 2−y2+idxy state occurs.
On MAP inference by MWSS on perfect graphs

Finding the most likely (MAP) configuration of a Markov random field (MRF) is NP-hard in general. A promising, recent technique is to reduce the problem to finding a maximum weight stable set (MWSS) on a derived weighted graph, which if perfect, allows inference in polynomial time. We derive new results for this approach, including a general decomposition theorem for MRFs of any order and number of labels, extensions of results for binary pairwise models with submodular cost functions to higher order, and an exact characterization of which binary pairwise MRFs can be efficiently solved with this method. This defines the power of the approach on this class of models, improves our toolbox and expands the range of tractable models.
Cross-Layer Estimation and Control for Cognitive Radio: Exploiting Sparse Network Dynamics

In this paper, a cross-layer framework to jointly optimize spectrum sensing and access in agile wireless networks is presented. A network of secondary users (SUs) accesses portions of the spectrum left unused by a network of licensed primary users (PUs). A central controller (CC) schedules the traffic of the SUs, based on distributed compressed measurements collected by the SUs. Sensing and access are jointly controlled to maximize the SU throughput, with constraints on PU throughput degradation and SU cost. The sparsity in the spectrum dynamics is exploited: leveraging a prior spectrum occupancy estimate, the CC needs to estimate only a residual uncertainty vector via sparse recovery techniques. The high complexity entailed by the POMDP formulation is reduced by a low-dimensional belief representation via minimization of the Kullback-Leibler divergence. It is proved that the optimization of spectrum sensing and access can be decoupled via dynamic programming. A partially myopic access strategy is proposed, proving that it allocates SU traffic to likely idle spectral bands. Simulation results show that this framework balances optimally the resources between spectrum sensing and data transmission. More in general, this framework defines sensing-scheduling schemes most informative for network control, yielding energy efficient resource utilization.
Fast and generalized polynomial time memory consistency verification

The problem of verifying multi-threaded execution against the memory consistency model of a processor is known to be an NP hard problem. However polynomial time algorithms exist that detect almost all failures in such execution. These are often used in practice for microprocessor verification. We present a low complexity and fully parallelized algorithm to check program execution against the processor consistency model. In addition our algorithm is general enough to support a number of consistency models without any degradation in performance. An implementation of this algorithm is currently used in practice to verify processors in the post silicon stage for multiple architectures.
Surviving progress: Managing the collective risks of civilization

As optimism is becoming ever more apparent, progress carries with it both promise and pitfalls. Though it is quite natural for humans to take an optimistic view of life, this optimism must at the same time be tempered with realism. We cannot therefore let a focus on average, or expected, outcomes cause us to ignore possible high-stakes (existential) risks associated with what is becoming an increasingly complex world. In this paper, we argue that a more complete view is necessary for a proper assessment of not only the technical aspects of high-stakes risk management, but also the social, political, and economic framework within which it is carried out. Unfortunately, attention to such crucial details is not often the case.
Effective cones of quotients of moduli spaces of stable $n$-pointed curves of genus zero

Let X n := M 0,n , the moduli space of n-pointed stable genus zero curves, and let X n,m be the quotient of X n by the action of S n-m on the last n - m marked points. The cones of effective divisors NE 1 (X n,m ), m = 0, 1, 2, are calculated. Using this, upper bounds for the cones Mov(X n,m ) generated by divisors with moving linear systems are calculated, m = 0,1, along with the induced bounds on the cones of ample divisors of M g and M g,1 . As an application, the cone NE 1 (M 2,1 ) is analyzed in detail.