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"This is the pre-peer reviewed version of the following article: Banks D, Gallego V, Naveiro R, Ríos Insua D. Adversarial risk analysis: An overview. WIREs Comput Stat. 2020;e1530. https://doi.org/10.1002/wics.153016, which has been published in final form at https://onlinelibrary.wiley.com/doi/epdf/10.1002/wics.1530. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.", Adversarial risk analysis (ARA) is a relatively new area of research that informs decision-making when facing intelligent opponents and uncertain outcomes. It is a decision-theoretic alternative to game theory. ARA enables an analyst to express her Bayesian beliefs about an opponent's utilities, capabilities, probabilities, and the type of strategic calculations that the opponent is using to make his decision. Within that framework, the analyst then solves the problem from the perspective of the opponent. This calculation produces a distribution over the actions of the opponent that permits the analyst to maximize her expected utility. This review covers conceptual, modeling, computational, and applied issues in ARA as well as interesting open research issues., Unión Europea. Horizonte 2020, Ministerio de Ciencia e Innovación (MICINN)/FEDER, Ministerio de Ciencia e Innovación (MICCIN), National Science Foundation, Depto. de Estadística e Investigación Operativa, Fac. de Ciencias Matemáticas, FALSE, pub

Machine learning and computational processing have advanced such that automated driving systems (ADSs) are no longer a distant reality. Many automobile manufacturers have developed prototypes; however, there exist numerous decision support issues requiring resolution to ensure mass ADS adoption. In the coming decades, it is likely that production ADSs will only be partially autonomous. Such ADSs operate within predetermined conditions and require driver intervention when they are violated. Since forecasts of their 20-year market penetration are relatively low, ADSs will likely operate in heterogeneous traffic characterized by vehicles of varying autonomy levels. Under these conditions, effective decision support must consider intangible, subjective, and emotional factors as well as influences of human cognition; otherwise, the ADS risks driver distrust and unsatisfactory performance based on an incomplete understanding of its environment. We survey the literature relevant to these issues, identify open problems, and propose research directions for their resolution.

We argue that adversarial risk analysis may be incorporated into the structured expert judgement modelling toolkit for cases in which we need to forecast the actions of competitors based on expert knowledge. This is relevant in areas such as cybersecurity, security, defence and business competition. As a consequence, we present a structured approach to facilitate the elicitation of probabilities over the actions of other intelligent agents by decomposing them into multiple, but simpler, assessments later combined together using a rationality model of the adversary to produce a final probabilistic forecast. We then illustrate key concepts and modelling strategies of this approach to support its implementation.

[EN] Recent studies have suggested that there has been a decrease in passive use, and an increase in the use of first person pronouns in scientific writing. This study looks at six sample texts from the physical sciences. The correlation between low passive use and use of first person pronoun subjects is only partial. The influx of verbs of a mathematical nature in recent decades has led to an increase in verbs of mental process. These lend themselves more easily to the use of first person pronouns. There are now two models available, a progressive model using fewer passives and a number of first person pronoun subjects, and a traditional model using passive forms extensively and avoiding first person pronoun subjects.

Studies of populations of gold particles are becoming increasingly common; however, interpretation of compositional data may not be straightforward. Natural gold is rarely homogenous. Alloy heterogeneity is present as microfabrics formed either during primary mineralization or by modification of pre-existing alloys by chemical and physical drivers during subsequent residence in either hypogene or surficial environments. In electron-probe-microanalysis (EPMA)-based studies, the combination of Cu, Hg, and Pd values and mineral inclusion suites may be diagnostic for source style of mineralization, but Ag alone is rarely sufficient. Gold characterization studies by laser-ablation-ICP mass spectrometry linked to both quadrupole and Time-of-Flight (ToF-MS) systems show that only Ag, Cu, and Hg form homogenous alloys with Au sufficiently often to act as generic discriminants. Where present, other elements are commonly distributed highly heterogeneously at the micron or submicron scale, either as mineral inclusions or in highly localized, but low concentrations. Drawing upon our own data derived from individual inspection and analyses of approximately 40,000 gold particles from 526 placer and in situ localities worldwide, we show that adequate characterization of gold from a specific locality normally requires study of a minimum of 150 particles via a two-stage approach comprising spatial characterization of compositional heterogeneity, plus crystallographic orientation mapping, that informs subsequent targeted acquisition of quantitative compositional data by EPMA and/or laser-ablation ICP-MS methods. Such data provide the platform to review current understanding of the genesis of gold particle characteristics, elevating future compositional studies from empirical descriptions to process-focused interpretations.

Deep learning (DL) has gained much attention and become increasingly popular in modern data science. Computer scientists led the way in developing deep learning techniques, so the ideas and perspectives can seem alien to statisticians. Nonetheless, it is important that statisticians become involved -- many of our students need this expertise for their careers. In this paper, developed as part of a program on DL held at the Statistical and Applied Mathematical Sciences Institute, we address this culture gap and provide tips on how to teach deep learning to statistics graduate students. After some background, we list ways in which DL and statistical perspectives differ, provide a recommended syllabus that evolved from teaching two iterations of a DL graduate course, offer examples of suggested homework assignments, give an annotated list of teaching resources, and discuss DL in the context of two research areas., Comment: 19 pages, accepted by Journal of Statistical Theory and Practice

The world-class Cuiabá gold deposit of the Archaean Rio das Velhas greenstone belt in Brazil is hosted in banded iron formation containing carbonaceous matter and carbonate, within the reclined, isoclinal Cuiabá fold. Mineralised quartz veins are hosted in andesite in the stratigraphic footwall of the banded iron ores and form some of the more recently discovered ore bodies. Fluid inclusion data of the quartz vein–associated “Veio de Quartzo” ore body are obtained from four quartz types (Qz1, Qz2, Qz3, Qz5) in gold-mineralised V1 shear vein and V2 extensional veins, barren V3 extensional vein array, and V4 breccia-style veins, all developed during the Archaean D1 event. Three fluid types are distinguished: (i) aqueous fluids of low salinity (1.8–3.8 wt% NaCl equiv), homogenisation (into liquid) at 220 to 230 °C; (ii) aqueous fluids of moderate salinity (5.3–12.7 wt% NaCl equiv), and homogenisation at 250 to 290 °C; and (iii) aqueous-carbonic fluids of moderate salinity (6.0–15.1 wt% NaCl equiv), with 30–91 mol% CO2, 8–41 mol% CH4 and up to 28 mol% N2 and decrepitation (into vapour) at 280 to 310 °C. Based on an independent pressure estimate, a pressure correction was applied to aqueous fluid inclusions, resulting in minimum trapping temperatures at 360 °C for V1 veins, 330 °C for V2 veins, 300 °C for V3 veins and 270 °C for the late-stage V4 veins. Ion chromatography analyses reveal a Br/Cl ratio of 0.7 × 10−3 in Qz1-V1, from 1.4 to 1.5 × 10−3 in Qz2-V2, 0.3 to 0.4 × 10−3 in Qz3-V3 and 0.7 to 0.9 × 10−3in Qz5-V4 veins. Zinc, Pb and Cu are relatively enriched with ~ 100 to 1000 ppm in aqueous and aqueous-carbonic fluid inclusion assemblages in all vein and quartz types, which is similar to other orogenic gold deposits hosted in the Rio das Velhas greenstone belt. The fluid inclusion data are consistent with a model invoking a metamorphic origin for the mineralising fluid. A two-step model of hydrothermal fluid flow and gold enrichment is suggested to have developed d

Adversarial risk analysis (ARA) is a relatively new area of research that informs decision-making when facing intelligent opponents and uncertain outcomes. It enables an analyst to express her Bayesian beliefs about an opponent's utilities, capabilities, probabilities and the type of strategic calculation that the opponent is using. Within that framework, the analyst then solves the problem from the perspective of the opponent while placing subjective probability distributions on all unknown quantities. This produces a distribution over the actions of the opponent that permits the analyst to maximize her expected utility. This overview covers conceptual, modeling, computational and applied issues in ARA.

Adversarial risk analysis (ARA) is a relatively new area of research that informs decision¿making when facing intelligent opponents and uncertain outcomes. It is a decision¿theoretic alternative to game theory. ARA enables an analyst to express her Bayesian beliefs about an opponent's utilities, capabilities, probabilities, and the type of strategic calculations that the opponent is using to make his decision. Within that framework, the analyst then solves the problem from the perspective of the opponent. This calculation produces a distribution over the actions of the opponent that permits the analyst to maximize her expected utility. This review covers conceptual, modeling, computational, and applied issues in ARA as well as interesting open research issues.

[EN] The first two academic periodicals were the Journal des Sçavans and the Philosophical Transactions which appeared within two months of each other in early 1665. At that time France was totally stable and centralized, while England was just emerging from a half-century of chaos. The first issue of the Philosophical Transactions included an item translated from the Journal des Sçavans. Study of these two texts shows that the English translator (Oldenburg) attempted to tidy up the French text. Analysis of the thematic structure, in comparison with a larger sample for the year 1665, shows that Oldenburg aligns his translation with his source text. Analysis of the process types shows that the percentages of process types are similar for the two texts, with the exception of verbal process. This seems to indicate a desire on the part of Oldenburg the attribute the discourse to someone else. These two texts are of particular importance as the first example of the translation of an academic article.

This research program investigated the potential energy savings to be gained by retrofitting non-domestic buildings in California with natural ventilation for cooling. The simplest and most cost effective retrofit is to open windows on the façade and turn off any mechanical ventilation. To make the problem tractable attention was restricted to wind-driven natural ventilation. Stack-driven ventilation is likely to also be present in practice, and usually improves the cooling potential.The program was split into three major projects. Project 1 assessed the potential of and the barriers to the implementation of natural ventilation. Project 2 examined induced air movement and the possible ingress of outdoor pollutants. Project 3 produced new tools for predicting the energy performance of naturally ventilated buildings, and provided training in their use.The major barriers to the introduction are the lack of specific design guidance and a lack to easy-to-use modeling tools. These are compounded by a lack of design experience and case studies and the mandatory requirements for the amount and location of openable area specified in Title 24.Research on wind-driven natural ventilation using computational fluid dynamics and wind tunnel tests provided new algorithms for cross ventilation, single-sided ventilation and corner ventilation, accounting for opening size, location and number, and the effects of sheltering by neighboring buildings. These algorithms were implemented in EnergyPlus, and the new version of the code was used in three training sessions to provide the design and engineering community with some familiarity in the new modules that calculate natural ventilation.The overall outcome of this program is a comprehensive study of the current issues concerning retrofitting commercial buildings in California and an assessment of the potential risks and benefits. It has also significantly extended the capabilities for modeling, design, and operation of naturally ventila

This essay proposes that those seeking to build counter-power institutions and communities learn to think in terms of what I call “recursivity.” Recursivity is an anti-authoritarian metric that helps bring about a sensitivity to feedback loops at multiple levels of organization. I begin by describing how technological systems and the socio-economic order co-constitute one-another around efficiency metrics. I then go on to define recursivity as social conditions that contain within them all of the parts and practices for their maturation and expansion, and show how organizations that demonstrate recursivity, like the historical English commons, have been marginalized or destroyed all together. Finally, I show how the ownership of property is inherently antithetical to the closed loops of recursivity. All of this is bookended by a study of urban planning’s recursive beginnings., Esse ensaio propõe que aqueles que buscam construir instituições e comunidades contra-poder aprendam a pensar em termos do que eu chamo de “recursividade” (“recursivity”). Recursividade é uma métrica anti-autoritária que ajuda a trazer uma sensibilidade aos laços de retro-alimentação (feedback loops) em níveis múltiplos de organização. Eu começo por descrever como sistemas tecnológicos e a ordem sócio-econômica co-constituem uma a outra em torno de métricas de eficiência. Passo então a definir recursividade como as condições sociais que contém em seu interior todas as partes e práticas para a sua maturação e expansão, e mostro como as organizações que apresentam recursividade, como o histórico English commons, tem sido marginalizadas e destruídas. Finalmente, demonstro como a posse da propriedade é inerentemente anti-ética aos laços fechados da recursividade. Todo o artigo está baseado por um estudo de recursos iniciais para planejamento urbano.

Adversarial risk analysis has been introduced as a framework to deal with risks derived from intentional actions of adversaries. The analysis supports one of the decisionmakers, who must forecast the actions of the other agents. Typically, this forecast must take account of random consequences resulting from the set of selected actions. The solution requires one to model the behavior of the opponents, which entails strategic thinking. The supported agent may face different kinds of opponents, who may use different rationality paradigms, for example, the opponent may behave randomly, or seek a Nash equilibrium, or perform level-k thinking, or use mirroring, or employ prospect theory, among many other possibilities. We describe the appropriate analysis for these situations, and also show how to model the uncertainty about the rationality paradigm used by the opponent through a Bayesian model averaging approach, enabling a fully decision-theoretic solution. We also show how as we observe an opponent's decision behavior, this approach allows learning about the validity of each of the rationality models used to predict his decision by computing the models' (posterior) probabilities, which can be understood as a measure of their validity. We focus on simultaneous decision making by two agents.

Approximation theory plays an important role in image processing, especially image deconvolution and decomposition. For piecewise smooth images, there are many methods that have been developed over the past thirty years. The goal of this study is to devise similar and practical methodology for handling textured images. This problem is motivated by forensic imaging, since fingerprints, shoeprints and bullet ballistic evidence are textured images. In particular, it is known that texture information is almost destroyed by a blur operator, such as a blurred ballistic image captured from a low-cost microscope. The contribution of this work is twofold: first, we propose a mathematical model for textured image deconvolution and decomposition into four meaningful components, using a high-order partial differential equation approach based on the directional mean curvature. Second, we uncover a link between functional analysis and multiscale sampling theory, e.g., harmonic analysis and filter banks. Both theoretical results and examples with natural images are provided to illustrate the performance of the proposed model., Comment: 72 pages, including main manuscript (36 pages) and Appendix (36 pages); 14 figures; journal

The last decade has seen great progress in both dynamic network modeling and topic modeling. This paper draws upon both areas to create a Bayesian method that allows topic discovery to inform the latent network model and the network structure to facilitate topic identification. We apply this method to the 467 top political blogs of 2012. Our results find complex community structure within this set of blogs, where community membership depends strongly upon the set of topics in which the blogger is interested., Comment: Accepted at Journal of Classification

In dynamic topic modeling, the proportional contribution of a topic to a document depends on the temporal dynamics of that topic's overall prevalence in the corpus. We extend the Dynamic Topic Model of Blei and Lafferty (2006) by explicitly modeling document level topic proportions with covariates and dynamic structure that includes polynomial trends and periodicity. A Markov Chain Monte Carlo (MCMC) algorithm that utilizes Polya-Gamma data augmentation is developed for posterior inference. Conditional independencies in the model and sampling are made explicit, and our MCMC algorithm is parallelized where possible to allow for inference in large corpora. To address computational bottlenecks associated with Polya-Gamma sampling, we appeal to the Central Limit Theorem to develop a Gaussian approximation to the Polya-Gamma random variable. This approximation is fast and reliable for parameter values relevant in the text mining domain. Our model and inference algorithm are validated with multiple simulation examples, and we consider the application of modeling trends in PubMed abstracts. We demonstrate that sharing information across documents is critical for accurately estimating document-specific topic proportions. We also show that explicitly modeling polynomial and periodic behavior improves our ability to predict topic prevalence at future time points.

2014 University Libraries Undergraduate Research Award Winner---Perhaps some of the most complex disorders that have been observed in humans are those that concern emotion and processes of the human brain. The pathway between stimulus and response in cases of depression and anxiety is one that can take many directions depending on the patient in question; for this reason, psychiatry has provided interesting modes by which pathology can be studied outside of a one-to-one causal relationship. Given the expected lifespan of the average individual and the decades through which different disorders can emerge and withdraw given changes in environment or situation, determining the cause of such pathologies as Chronic Fatigue Syndrome (CFS) or even Obsessive-Compulsive Disorder (OCD) can be daunting for any physician. How does one trace a pattern of feeling or behavior back to a causal event that may have occurred years before symptoms even emerged? In an age where Post-Traumatic Stress Disorder (PTSD) continues to gain relevance in light of a world at war, such questions must be asked. The lives of patients and their families depend on the ability of scientists to uncover pathways that can be manipulated to produce some treatment option or cure. After Dr. James Greenblatt was sought out by the parents of a young girl named Mary who had been diagnosed with a mixture of psychiatric disorders, including OCD and Attention Deficit Hyperactivity Disorder (ADHD), and treated with a range of psychotropic drugs that had remained largely unhelpful, his mode of thinking was able to change her quality of life (James 2013). He turned to her stomach as a possible root of the problem. One may not expect a trip to the psychiatrist to include a survey of questions aimed at ascertaining his or her digestive health; however, Dr. Greenblatt employed this strategy and, because of his conclusion that the symptoms that were manifesting in the emotive regions of Mary's brain might actually origin

The Philosophical Transactions was founded by Henry Oldenburg in 1665. The contents of the journal were based on his correspondence, and initially consisted of extracts from the many letters he received. The scope of the journal was that of "natural philosophy", or science and technology in contemporary terms. The linguistic features of its early issues are of particular interest. Among these is that of modality. A previous study indicated that the most common form used to express modality is that of the modal auxiliaries, and the most frequent auxiliaries are may and will. The type of modality that is most commonly expressed is dynamic. Study of an enlarged sample confirms the dominance of auxiliaries but the specific auxiliaries used vary from issue to issue. It also confirms the dominance of dynamic modality. This is consistent with the focus on physical observation and experiment which was adopted by the Royal Society.

Route selection in hostile terrain is a problem in adversarial risk analysis (ARA). This report summarizes work done to date that addresses the routing problem from the perspective of decision analysis, which takes account of both asymmetric uncertainties and the strategy of an intelligent opponent. The methodology is novel, and usefully different from traditional game theory or risk analysis. The main results of this funding are (1) a paper that is under second review by 'Naval Research Logistics' and (2) presentations at a number of conferences and colloquia., The original document contains color images.

The fluorite deposits of Asturias (northern Iberian Peninsula) are hosted by rocks of Permo-Triassic and Palaeozoic age. Fluid inclusions in ore and gangue minerals show homogenization temperatures from 80 to 170C and the presence of two types of fluids: an H2O–NaCl low-salinity fluid (<8 eq. wt% NaCl) and an H2O–NaCl–CaCl2 fluid (7–13 wt% NaCl and 11–14 wt% CaCl2). The low salinity and the Cl ⁄ Br and Na ⁄ Br ratios (Cl ⁄ Brmolar 100–700 and Na ⁄ Brmolar 20–700) are consistent with an evaporated sea water origin of this fluid. The other end-member of the mixture was highly saline brine with high Cl ⁄ Br and Na ⁄ Br ratios (Cl ⁄ Brmolar 700–13 000 and Na ⁄ Brmolar 700–11 000) generated after dissolution of Triassic age evaporites. LA-ICP-MS analyses of fluid inclusions in fluorite reveal higher Zn, Pb and Ba contents in the high-salinity fluids (160–500, 90–170, 320–480 p.p.m. respectively) than in the low-salinity fluid (75–230, 25–150 and 100–300 p.p.m. respectively). The metal content of the fluids appears to decrease from E to W, from Berbes to La Collada and to Villabona. The source of F is probably related to leaching of volcanic rocks of Permian age. Brines circulated along faults into the Palaeozoic basement. Evaporated sea water was present in permeable rocks and faults along or above the unconformity between the Permo-Triassic sediments and the Palaeozoic basement. Mineralization formed when the deep brines mixed with the surficial fluids in carbonates, breccias and fractures resulting in the formation of veins and stratabound bodies of fluorite, barite, calcite, dolomite and quartz and minor amounts of sulphides. Fluid movement and mineralization occurred between Late Triassic and Late Jurassic times, probably associated with rifting events related to the opening of the Atlantic Ocean. This model is also consistent with the geodynamic setting of other fluorite-rich districts in Europe., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

In 2006, the Department of Homeland Security (DHS) completed its first Bioterrorism Risk Assessment (BTRA), intended to be the foundation for DHS s subsequent biennial risk assessments mandated by Homeland Security Presidential Directive 10 (HSPD-10). At the request of DHS, the National Research Council established the Committee on Methodological Improvements to the Department of Homeland Security s Biological Agent Risk Analysis to provide an independent, scientific peer review of the BTRA. The Committee found a number of shortcomings in the BTRA, including a failure to consider terrorists as intelligent adversaries in their models, unnecessary complexity in threat and consequence modeling and simulations, and a lack of focus on risk management. The Committee unanimously concluded that an improved BTRA is needed to provide a more credible foundation for risk-informed decision making., Published in the Journal of Biosecurity and Bioterrorism: Biodefense Strategy, Practice, and Science, v6 n4 p1-4, 2008.

The subject of this thesis is the study of the Laser Induced Forward Transfer (LIFT) technique with femtosecond duration pulses. In principle, femtosecond-LIFT should offer a number of advantages over traditional nanosecond-LIFT in terms of achievable resolution and transferring intact and solid phase material.A novel solid phase etching technique that uniquely allows for simultaneous deposition of the etched material, also in solid phase, has been presented. Micron deep holes and trenches have been produced in Si and silica substrates by the generation of large shocks in a thin Cr layer by absorption of femtosecond pulses. The shock initiated the propagation of cracks in the bulk substrates that ultimately lead to etching of whole sections of material.

The spreadsheet has been used by the business community for many years and yet still raises a number of significant concerns. As educators our concern is to try to develop the students skills in both the development of spreadsheets and in taking a critical view of their potential defects. In this paper we consider both the problems of mechanical production and the problems of translation of problem to spreadsheet representation., Comment: 9 pages incuding references

A long-standing vision of the US Air Force and supporting industry has been to design and incorporate large antennas into military aircraft. However, as the apertures increase in size they typically require larger radomes or cut-outs in the primary load bearing structure of the airframe limiting the number and size of the apertures. This directly affects the structural and aerodynamic efficiency of the aircraft thus reducing the endurance. Therefore, the need to develop conformal load bearing antenna structures has become an area of specific interest of development to enhance military mission capability. The payoffs include improved antenna performance/gain through the much larger available antenna area, reduced support cost, lower weight, signature, and drag. Depending on location, the antennas will be required to bear primary or secondary structural loads, and to compensate the radio frequency (RF) beam pattern for structural deformations at high frequency applications. This paper documents work in progress towards the development of a very large structural x-band electronically scanned array (ESA). A building block approach that includes structural and RF array development is presented. The challenge of multidisciplinary integration has been directly addressed by bringing the structural and RF sciences together in order to develop an optimized design that meets functional requirements. At the time of this writing significant structural testing from coupon through large scale structural validation have been complete and is reported. The active array testing will evaluate a three square foot array under deformed conditions in an anechoic chamber, but is pending completion., Presented at the AVT-141 Specialists' Meeting held in Vilnius, Lithuania on 2-4 October 2006 and published in the proceedings as paper 17.See also ADM202433, Multifunctional Structures/Integration of Sensors and Antennas (Les structures multifonctionnelles/l'integration de capteurs et d'antennes), RTO-MP-AVT-141. The original document contains color images.

Laser ablation—inductively coupled plasma—mass spectrometry (LA-ICP-MS) has become recognized as a sensitive, efficient, and cost-effective approach to measuring the major-, minor-, and trace-solute compositions of individual fluid inclusions in minerals. As a prerequisite for the routine analysis of natural inclusions in our laboratory, the precision and accuracy of the technique was assessed using sets of multi-element synthetic fluid inclusions. Five multi-element standard solutions were prepared, and incorporated as fluid inclusions in quartz crystals at 750 °C and 7 kbar. Fluid inclusions were ablated with a 193 nm ArF excimer laser and analyzed with a quadrupole ICP-MS, equipped with an octopole reaction cell for the removal of Ar-based interferences. The internal standard used in all cases was Na. Analytical precision for K, Rb, and Cs is typically better than 15% RSD, whereas Li, Mg, Ca, Sr, Ba, Mn, Fe, Cu, Zn, and Cl analyses are typically reproducible within 30% RSD. Measured concentrations approximate a Gaussian distribution, suggesting that analytical errors are random. Analyses for most elements are accurate within 15%. Limits of detection vary widely according to inclusion volume, but are 1 to 100 μfor most elements. These figures of merit are in excellent agreement with previous studies. We also demonstrate that, over the range investigated, precision and accuracy are insensitive to inclusion size and depth. Finally, the combination of our LA-ICP-MS analyses with microthermometric data shows that charge-balancing to NaCl-H2O equivalent chloride molality is the most valid approach to LA-ICP-MS data reduction, where chloride-dominated fluid inclusions are concerned.

Certain groups in the United States remain at high risk and suffer disproportinately from tobacco-related illness and death despite progress made in reducing tobacco use. To address gaps in research on tobacco-related disparities and develop a comprehensive agenda aimed at reducing such disparities, representatives from funding agencies, community-based organizations, and academic institutions convened at the National Conference on Tobacco and Health Disparities in 2002. Conference participants reviewed the current research, identified existing gaps, and prioritized scientific recommendations. Panel discussions were organized to address research areas affecting underserved and understudied populations. We report major research recommendations will ultimately help guide the field in reducing and eliminating tobacco-related disparities in the United States.

Late fluids trapped in barren quartz veins from the Spanish Central System and a comparison with earlier fluids associated with W and fluorite mineralization ha ve been investigated in this papero Special attention has been paid 10 fluid chemistry using microthermometry and bulk leachate chemical analysis. Three different fluids have bcen recognized: (i) early H20-NaCI-C02-CH4. fluids associated with W-sulphide (ii) acueous H20-NaCI f1uids related to f1uorites (iii) acueous fluids associated with barren quartz veins. Two differcnt tluids characterized by H;p-NaCI and H20- NaCI-CaCI, systems have been recognized in these latest tluids. Li is present too. Possible origins for dissolved ion s in the fluids are discussed in this study. Different mincralizations have different origins.` [RESUMEN] En el presente trabajo se han investigación los fluidos tardíos atrapados en filones estériles de cuarzo del Sistema Central Español, a la vez que se ha realizado una comparación con fluidos asociados a mineralizaciones de W y de fluorita. Se ha llevado a cabo el estudio mediante un análisis combinado de microtermometría y química del fluido. Se han identificado tres tipos de fluidos: (i) fluidos tempranos acuoso-carbónicos (H20-NaCI-C02-CH4) asociados a mineralizaciones de W-sulfuros (ii) fluidos acuosos (H20-NaCI) asociados a tluoritas (iii) fluidos asociados a filones de cuarzo. En estos últimos se han reconocido dos fluidos acuosos diferentes caracterizados por los sistemas H20-NaCI y H20-NaCl-CaCl2, con presencia de Li. En este estudio se discute el posible orígen de los iones disueltos en los fluidos, que es diferente para cada tipo de mineralización., Depto. de Mineralogía y Petrología, Fac. de Ciencias Geológicas, TRUE, pub

We present a method for visualizing 2D and 3D flows by animating textures on triangles, taking advantage of texture mapping hardware. We discuss the problems when the flow is time-varying, and present solutions

We present a method for visualizing unsteady flow by displaying its vortices. The vortices are identified by using a vorticity-predictor pressure-corrector scheme that follows vortex cores. The cross-sections of a vortex at each point along the core can be represented by a Fourier series. A vortex can be faithfully reconstructed from the series as a simple quadrilateral mesh, or its reconstruction can be enhanced to indicate helical motion. The mesh can reduce the representation of the flow features by a factor of one thousand or more compared with the volumetric dataset. With this amount of reduction it is possible to implement an interactive system on a graphics workstation to permit a viewer to examine, in three dimensions, the evolution of the vortical structures in a complex, unsteady flow. (AN)

We describe an interactive, immersive 3D system called Tracktur, which allows a viewer to track the development of a turbulent flow. Tracktur displays time-varying vortex structures extracted from a numerical flow simulation. The user navigates the space and probes the data within a windy 3D landscape. In order to sustain a constant frame rate, we enforce a fixed polygon budget on the geometry. We supplement the interactive system with interactive, hypertext documentation available on the World Wide Web. In actual use by a fluid dynamicist, the system has yielded new insights into the transition to turbulence in a laminar flow. (AN)

This report details the engineering considerations of a program designed to investigate the effects of chronic low-level radiofrequency radiation (RFR) exposure on cell growth and differentiation. The protocol required the exposure (1 mW/cm2 20 hours daily AVERAGE, 7 days per week) of 200 female, mammary-tumor-prone mice (strain C3H/HeJ) to 435-MHz pulsed-wave (1.0 us pulse width, 1.0 kHz pulse rate) RFR for a duration of 21 months. In addition, a sham-exposure group consisting of 200 female, C3H/HeJ mice was housed under identical conditions, but not exposed to the 435-MHz pulsed-wave radiation. The program's engineering considerations involved developing and providing the facility and equipment used to expose the mammary-tumor-prone mice and the development of a procedure for reliable identification of the mice. Also described are the design of the antenna and transmitter system, animal caging, cage washing procedures, and the data collection system. Bioeffects of radiofrequency radiation, Mammary tumors and electromagnetic fields, Electromagnetic field studies.

When surfaces intersect, one may desire to highlight the intersection curve in order to make the shape of the penetrating surfaces more visible. Highlighting the intersection is especially helpful when the surfaces become transparent, because transparency makes the intersections less evident. This paper discusses a technique for locating intersections in screen space using only the information locally available to a pixel. The technique is designed to exploit parallelism at the pixel level and has been implemented on the Pixel- Planes 5 graphics supercomputer.

A 45-gigahertz radar has been developed that yields full-polarization inverse synthetic aperture radar images and instantaneous angle-of-arrival measurements for angular scintillation studies. The system is portable, self-contained, and suitable for measurements of radar cross-section ranges and open, unprepared sites. Measurements have been made successfully on large scale-model targets (8 meters in extent) at ranges up to 1000 meters.

International audience, The giant epithermal Ag-Hg deposit of Imiter (Morocco) is investigated to test a possible transfer of chalcophile elements from the mantle to superficial crustal levels during Pan African times. The accretion of the Anti-Atlas belt at the West African continent is characterized by a four stage succession of events, that is, extension, subduction, moderate collision and extension. The strongest metallogenic activity which is dominated by base- and precious metal deposit formation, occurs during the late extensional stage at the Precambrian-Cambrian transition. In the Imiter Ag-Hg deposit, the origin of metals and ligands, deduced from S, fluid inclusions, He, and Re/Os data obtained on sulphide phases and gangue minerals, had a dominantly mantle source.