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The 12th International Workshop on H-mode Physics and Transport Barriers was held at the Princeton Plasma Physics Laboratory, Princeton, New Jersey, USA between September 30 and October 2, 2009. This meeting was the continuation of a series of previous meetings which was initiated in 1987 and has been held bi-annually since then. Following the recent tradition at the last few meetings, the program was sub- divided into six sessions. At each session, an overview talk was presented, followed by two or three shorter oral presentations which supplemented the coverage of important issues. These talks were followed by discussion periods and poster sessions of contributed papers. The sessions were: Physics of Transition to/from Enhanced Confinement Regimes, Pedestal and Edge Localized Mode Dynamics, Plasma Rotation and Momentum Transport, Role of 3D Physics in Transport Barriers, Transport Barriers: Theory and Simulations and High Priority ITER Issues on Transport Barriers. The diversity of the 90 registered participants was remarkable, with 22 different nationalities. US participants were in the majority (36), followed by Japan (14), South Korea (7), and China (6). This special issue of Nuclear Fusion consists of a cluster of 18 accepted papers from submitted manuscripts based on overview talks and poster presentations. The paper selection procedure followed the guidelines of Nuclear Fusion which are essentially the same as for regular articles with an additional requirement on timeliness of submission, review and revision. One overview paper and five contributed papers report on the H-mode pedestal related results which reflect the importance of this issue concerning the successful operation of ITER. Four papers address the rotation and momentum transport which play a crucial role in transport barrier physics. The transport barrier transition condition is the main focus of other four papers. Finally, four additional papers are devoted to the behaviour and control of Edge Localized Modes. The selection of topics and overview speakers and the scientific programme were carried out by the International Advisory Committee, consisting of: R. Groebner (GA, USA), T.S. Hahm (PPPL, USA--Chair), A. Hubbard (MIT, USA), K. Ida (NIFS, Japan), S. Lebedev (Ioffe Institute, Russia), N. Oyama (JAEA, Japan), G. Saibene (F4E, EU) and W. Suttrop (IPP, Germany). Their work, advice, and participation contributed to the success of the meeting. Finally, I would like to express deep gratitude to J. Jones and B. Sarfaty who took care of numerous issues relating to the organization of the meeting, and to J.K. Park and several graduate students of the Princeton University Plasma Physics Program for helping with the transportation of participants. [ABSTRACT FROM AUTHOR]

In one of our recent studies, we have shown that a large defocusing distance in the transport of intensity equation (TIE) is required to retrieve the phase information in low-light conditions (OSA Continuum 3 (2020) 236). It has been found that image misalignment issues come into the picture due to translation of the camera for large distances, which creates artifacts in phase recovery. The issue of misalignment can be overcome if, instead of the object, we use the digital hologram of the object for the required defocused intensities and then apply the TIE. In this paper, we demonstrate low-light phase imaging by combining digital holography with the TIE. We reconstruct the required multiple intensity distributions from the captured in-line digital hologram. To implement the low-level light illumination, a variable neutral density filter has been used while recording the in-line digital hologram. Simulation and experimental results with different objects (United States air-force chart and glue drop) are presented. To simulate the low-light conditions, a Poisson distribution based photon-counting imaging technique has been applied. [ABSTRACT FROM AUTHOR]

Objective: Apneas are the most common type of sleep-related breathing disorders; they cause patients to move from restorative sleep into inefficient sleep. The American Academy of Sleep Medicine (AASM) considers sleep apnea as a hidden health crisis that affects 29.4 million adults, costing the USA billions of dollars. Traditional detection methods of sleep apnea are achieved by human observation of the respiration signals. This introduces limitations in terms of access and efficiency of diagnostic sleep studies. However, alternative device technologies have limited diagnostic accuracy for detecting apnea events although many of the previous investigational algorithms are based on multiple physiological channel inputs. Guided by the AASM recommendations for sleep apnea diagnostics, this paper investigates time domain metrics to characterize changes in oronasal airflow respiration signals during the occurrence of apneic events. Approach: A new algorithm is developed to derive a respiratory baseline from the oronasal airflow signal in order to detect sleep apnea events using a dynamically adjusted threshold classification approach. To demonstrate our results, we use polysomnography data of patients with different apnea severity levels as reflected by their overnight apnea hypopnea index (AHI), including patients with mild apnea (5 AHI ), moderate apnea ( AHI ), and severe apnea (AHI ). Main results: Our results indicate the ability to characterize sleep apnea events in oronasal airflow signals using the proposed dynamic threshold classification approach. Overall, the new algorithm achieved a sensitivity of 80.0%, specificity of 88.7%, and an area under receiver operating characteristics curve of 0.844. Significance: The present results contribute a new approach for progressive detection of sleep apnea using an adaptive threshold that is dynamically adjusted with respect to the patient’s respiration baseline, making it potentially able to effectively generalize over patients with different apnea severity levels and longer monitoring periods. [ABSTRACT FROM AUTHOR]

Lunar laser ranging (LLR) has for decades stood at the forefront of tests of gravitational physics, including tests of the equivalence principle (EP). Current LLR results on the EP achieve a sensitivity of &Dgr;a/athkap;10-13 based on few-centimeter data/model fidelity. A recent push in LLR, called APOLLO (the Apache Point Observatory Lunar Laser-ranging Operation) produces millimeter-quality data. This paper demonstrates the few-millimeter range precision achieved by APOLLO, leading to an expectation that LLR will be able to extend EP sensitivity by an order-of-magnitude to &Dgr;a/a ∼ 10-14, once modeling efforts improve to this level. [ABSTRACT FROM AUTHOR]

Phase-transformation electrodes have desirable characteristics for lithium-ion batteries. These electrodes have been shown to be abuse resistant, have extended cycle life, and are suitable for fast-charging applications. These new materials have significantly different lithium incorporation behaviors than the more-conventional solid-solution reaction electrodes. This paper explores the implications of phase-transformation physics within a multiparticle electrode that contains a distribution of particle sizes. Phase-transformation physics is such that lithium distributions within the electrode particle ensemble is cycle-path dependent. For example, after charging, any maldistribution of lithium between particles does not naturally redistribute uniformly between all particles, as is the case for solid-solution reaction electrodes. Such maldistribution greatly influences the observed electrochemical impedance spectra. The implications of history-dependent inter-particle lithium distributions is characterized with a mesoscopic model. The model shows how the impedance spectra of a phase-transformation electrode, at a prescribed state of charge, depends on the path history to achieve the state of charge. [ABSTRACT FROM AUTHOR]

This paper presents an overview of recent progress in the area of inertial fusion energy (IFE) safety and environment (S&E) in the US. Over the past several years, a significant effort has been devoted towards the development of S&E analyses for future IFE power plants. We have completed the safety assessment of various baseline IFE power plant concepts, including simulation of accident scenarios and accident consequences analyses, S&E studies of candidate target materials and discussions on waste management issues. The results from this work have allowed for a better understanding of the behaviour of radioactive sources and hazardous materials within the IFE power plant, identification of the energy sources that could mobilize those materials in case of an accident and assessment of waste management options for IFE. Currently, ongoing S&E studies for IFE are focusing on emerging design concepts, which include support to the high average power laser (HAPL) program for development of a dry-wall, laser-driven IFE power plant and collaboration with the Z-pinch IFE program for the production of an economically attractive power plant using high-yield Z-pinch-driven targets. In this paper, the main safety issues related to the HAPL and Z-IFE programs are reviewed, some recent safety highlights are presented and future directions in the IFE S&E area are proposed. [ABSTRACT FROM AUTHOR]

The learning assistant (LA) model is a widely used and researched model for institutional and course transformation towards research-based instructional strategies (RBIS). The LA model leverages learning assistants, pedagogically trained students, to facilitate student learning in active learning environments. However, although the LA model has shown significant results when implemented in university contexts in the United States, there has as yet been little documentation of similar implementation or results in European higher education. In this study, we present the results of a three-semester design-based research project to implement the LA Model in a Scandinavian physics department. The three core elements of the LA model (pedagogical training, course content meetings, and teaching in active learning environments) were implemented and iteratively refined, with necessary adjustments due to the specific institutional and cultural contexts documented. Throughout all three semesters, data was collected on how participation in the LA model affected LAs' buy-in to RBIS using focus groups, pre/post surveys, and teaching observations. A thematic analysis of these data showed that participation in the LA model helped ensure LA buy-in to both the interactive engagement methods and goal of cultivating conceptual understanding that underlie most RBIS, and that the combination of teaching practice and pedagogical training seminars were key to this buy-in. We argue that these results demonstrate the potential usefulness of the LA model for creating institutional and cultural change in European higher education. [ABSTRACT FROM AUTHOR]

This article focuses on the Electrochemical Society's 204th meeting held at Orlando, Florida. Attendees had the opportunity to choose from 1,491 technical papers on a broad range of topics. In addition to the technical papers, four short courses were held: Basics of Cleaning Processes for Integrated Circuit Manufacturing, taught by K. Reinhardt, J. Butterbaugh, J. Farber, and R. Small; Battery Design and Simulation, taught by R. Spotnitz; Impedance Spectroscopy: Theory and Applications, taught by M. E. Orazem; and Principles of PEM Fuel Cell Engineering I: Water Management and Flow Field Plate Design, taught by E. Stuve.

The magnetic dipole polarizability tensor of a metallic object gives unique information about the size, shape and electromagnetic properties of the object. In this paper, we present a novel method of coin characterization based on the spectroscopic response of the absolute tensor. The experimental measurements are validated using a combination of tests with a small set of bespoke coin surrogates and simulated data. The method is applied to an uncirculated set of US coins. Measured and simulated spectroscopic tensor responses of the coins show significant differences between different coin denominations. The presented results are encouraging as they strongly demonstrate the ability to characterize coins using an absolute tensor approach. [ABSTRACT FROM AUTHOR]

The form and function of a collaborative assessment known as a 'Buddy Quiz' is presented. The assessment is conducted in three successive phases over a contiguous 45-60 min class period. A portion of each quiz is completed in collaboration with one or two peers and a portion is completed without collaboration. The quiz is primarily summative and is also designed to include formative aspects. The representation in the quiz of the scientific enterprise as collaborative and individualistic is discussed. The employment of this instrument in a ninth-grade (age 15 years) conceptual physics course in an independent US secondary school is described and student feedback is presented [ABSTRACT FROM AUTHOR]

We present deep near-IR (NIR) medium-bandwidth photometry over the wavelength range 1-1.8 μm in the All-wavelength Extended Groth strip International Survey (AEGIS) and Cosmic Evolution Survey (COSMOS) fields. The observations were carried out using the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) on the Mayall 4 m Telescope on Kitt Peak as part of the NEWFIRM Medium-Band Survey (NMBS), an NOAO survey program. In this paper, we describe the full details of the observations, data reduction, and photometry for the survey. We also present a public K-selected photometric catalog, along with accurate photometric redshifts. The redshifts are computed with 37 (20) filters in the COSMOS (AEGIS) fields, combining the NIR medium-bandwidth data with existing UV (Galaxy Evolution Explorer), visible and NIR (Canada-France-Hawaii Telescope and Subaru Telescope), and mid-IR (Spitzer/IRAC) imaging. We find excellent agreement with publicly available spectroscopic redshifts, with σz/(1 + z) ~ 1%-2% for ~4000 galaxies at z = 0-3. The NMBS catalogs contain ~13,000 galaxies at z > 1.5 with accurate photometric redshifts and rest-frame colors. Due to the increased spectral resolution obtained with the five NIR medium-band filters, the median 68% confidence intervals of the photometric redshifts of both quiescent and star-forming galaxies are a factor of about two times smaller when comparing catalogs with medium-band NIR photometry to NIR broadband photometry. We show evidence for a clear bimodal color distribution between quiescent and star-forming galaxies that persists to z ~ 3, a higher redshift than has been probed so far. [ABSTRACT FROM AUTHOR]

This article presents 2003 annual report of Electrochemical Society (ECS). With 4,430 presentations, the Society's two meetings in 2003 combined drew the largest number of papers ever scheduled. The two meetings also drew the largest number of attendees ever: 4,618. At 2,936, the spring 2003 meeting in Paris alone drew the single largest number of attendees for a single, non-jointly sponsored ECS meeting. The fall 2003 meeting was held in Orlando, Florida, a new meeting destination for ECS. Many attendees brought their families to enjoy Disney World and the other Orlando attractions during the meeting week.

This article focuses on views of the author, who is the winner of 2003 Olin Palladium Award, on conducting research in the digital era. At the University of Pennsylvania, Philadelphia the author met Srinivasan Subramanian, called Srini for short, who has been his good friend ever since. When there was an equation to solve Srini would look at it, think a minute, and write down the solution. He was the mathematical wizard for students. They spend time for nearly three years, learned a lot from each other, wrote a few papers together, and consoled each other when the going got rough.

The hazards associated with radium-containing materials were largely unknown when they were first introduced into household and other products over a century ago. Radium was also originally thought to have beneficial health properties, leading to confusion amongst the public about the safety of radium in household products and food items. When the adverse health effects associated with radium were discovered and became well known, radium products became unpopular and were prohibited in some countries. In the United States, after the hazards associated with radium became known, radium was first regulated by individual states in the late 1920s and early 1930s. Later, the US Nuclear Regulatory Commission (NRC) was given a role in the regulation of discrete sources of radium with the passage of the Energy Policy Act of 2005. After passage of the Act, the NRC began to systematically identify sites around the country where radium was used and reached out to site owners to determine whether existing radium contamination could pose a risk to public health and safety and the environment. The NRC devised a graded approach in response to its new regulatory responsibilities to address potential public health and safety issues at legacy radium sites. By September 2019, the NRC had dispositioned all the sites that were identified as having potential contamination from historical radium within its regulatory purview in non-Agreement States. The staff worked with site owners and federal, state and local officials, as needed, to properly disposition the sites to ensure that each site either meets the applicable criteria for unrestricted use or has controls in place to limit access during remediation so that no site poses an unacceptable risk to public health and safety and the environment. [ABSTRACT FROM AUTHOR]

In their study of physics beyond the first year of University—termed upper-division in the US, many of students’ primary learning opportunities come from working long, complex back-of-the-book style problems, and from trying to develop an understanding of the underlying physics through solving such problems. Some of the research at the upper-division focuses on how students use mathematics in these problems, and what challenges students encounter along the way. There are a number of different and diverse research studies on students’ use of mathematics in the upper-division. These typically utilize one of two broad approaches, with some researchers primarily seeking out and addressing challenges students face, and others working chiefly to unpack students’ in-the-moment reasoning. In this paper, we present and discuss both approaches, and then review research efforts that strive to connect these two approaches in order to make sense of students’ use of mathematics as well as to uncover particular challenges that students encounter. These recent efforts represent a small step towards synthesizing the two approaches, which we argue is necessary to more meaningfully impact student learning at the upper-division. We close our review and discussion with suggested refinements for future research questions for the physics education research community to consider while it works to understand how students use math in upper-division courses. [ABSTRACT FROM AUTHOR]

The US Nuclear Data Program is charged with collecting, analyzing and archiving information critical to basic nuclear research and to the development of nuclear technologies. Users of nuclear data require detailed uncertainty information for a variety of reasons. In this paper, we review some of the main aspects of the generation and use of uncertainty information, linking to structure, astrophysics, and reaction data. [ABSTRACT FROM AUTHOR]

Background: Aortic stenosis (AS) is the most common cause for valve replacement in the United States. The pathophysiology of AS involves obstruction to the left ventricular (LV) outflow and reduced arterial compliance. The intrinsic frequency (IF) method is a system-based approach for hemodynamic monitoring of the LV-arterial system and involves determination of ω1 and ω2, which represent the dynamics of LV systolic and vascular function, respectively. Total frequency variation of the systemic circulation is the difference between these IFs (Δω = ω1– ω2). Objective: Our goal in this study was to investigate whether Δω, obtained from the ascending aortic pressure waveform, can be indicative of LV-arterial coupling after transcatheter aortic valve replacement (TAVR). Approach: Thirty patients undergoing elective TAVR for severe, symptomatic AS were included. We applied the IF method to assess the immediate effects of TAVR on LV-arterial coupling. Main results: Mean age was 86 ± 4 years, 50% were male with a mean aortic valve area of 0.7 cm2 and mean ejection fraction (EF) of 59 ± 7%. The results showed a significant decrease in Δω (47.6 to 9.5 bpm, p < 0.00001) and a significant increase in ω2 (51.9 to 84.6 bpm, p < 0.00001) immediately post TAVR. Significance: These preliminary findings indicate that the IF method can be used to evaluate improvements in LV hemodynamics immediately following TAVR. Use of the IF method may have implications for patients undergoing TAVR with impaired LV systolic function. [ABSTRACT FROM AUTHOR]

We investigate the impact of financial factors on daily volume recurrent time intervals in the developing Chinese stock markets. The tails of probability distribution functions (PDFs) of volume recurrent intervals behave as a power-law, and the scaling exponent decreases with the increase of stock lifetime, which are similar to those in the US stock markets, and they are typical representatives of developed markets. The difference is that the power-law exponent values remain almost the same with the changes of market capitalization, mean volume, and mean trading value, respectively. These findings enrich the results for event statistics for financial markets. [ABSTRACT FROM AUTHOR]

Presents some of the highlights of the 193rd Meeting of the Electrochemical Society Incorporated (ECS) held for the first time in San Diego, California in May. Number of attendees; Number of papers presented in 35 symposia; Number of booths and displays presented; Statements from C. Judson King, provost and senior vice-president of the University of California (UC); Information on Dr. Walther G. Grot's award address. INSET: Board highlights.

Through analysis the actual coal supply and demand in the US and China, the properties of the coal supply-demand market in both countries are investigated based on the energy supply-demand network. The validity of our model is verified by comparing numerical results with empirical results. The comparison of empirical results and the comparison of coal network model parameters between in the US and in China reveal the essence of the internal differences and similarities of coal supply and demand in these two countries. The third stage of China's coal network was close to that of the US in 1995, indicating that the evolutional situation of China's coal market begins to transit to an oligopolistic type. Finally, suggestions for China's coal supply-demand strategy are put forward. [ABSTRACT FROM AUTHOR]

We report results from five day very long baseline inter aerometry observations of the well-known quasar 3C 279 at 1.3 mm (230 GHz) in 2011. The measured nonzero closure phases on triangles including stations in Arizona, California, and Hawaii indicate that the source structure is spatially resolved. We find an unusual inner jet direction at scales of ~1 pc extending along the northwest-southeast direction (P.A. = 127° ± 3°), as opposed to other (previously) reported measurements on scales of a few parsecs showing inner jet direction extending to the southwest. The 1.3 mm structure corresponds closely with that observed in the central region of quasi-simultaneous super-resolution Very Long Baseline Array images at 7 mm. The closure phase changed significantly on the last day when compared with the rest of observations, indicating that the inner jet structure may be variable on daily timescales. The observed new direction of the inner jet shows inconsistency with the prediction of a class of jet precession models. Our observations indicate a brightness temperature of ~8 × 1010 K in the 1.3 mm core, much lower than that at centimeter wavelengths. Observations with better uv coverage and sensitivity in the coming years will allow the discrimination between different structure models and will provide direct images of the inner regions of the jet with 20-30 μas (5-7 light months) resolution. [ABSTRACT FROM AUTHOR]

Inertial fusion research is approaching a critical milestone, namely the demonstration of ignition and burn. The world's largest high-power laser, the National Ignition Facility (NIF), is under operation at the Lawrence Livermore National Laboratory (LLNL), in the USA. Another ignition machine, Laser Mega Joule (LMJ), is under construction at the CEA/CESTA research centre in France. In relation to the National Ignition Campaign (NIC) at LLNL, worldwide studies on inertial fusion applications to energy production are growing. Advanced ignition schemes such as fast ignition, shock ignition and impact ignition, and the inertial fusion energy (IFE) technology are under development. In particular, the Fast Ignition Realization Experiment (FIREX) at the Institute of Laser Engineering (ILE), Osaka University, and the OMEGA-EP project at the Laboratory for Laser Energetics (LLE), University Rochester, and the HiPER project in the European Union (EU) for fast ignition and shock ignition are progressing. The IFE technology research and development are advanced in the frameworks of the HiPER project in EU and the LIFE project in the USA. Laser technology developments in the USA, EU, Japan and Korea were major highlights in the IAEA FEC 2010. In this paper, the status and prospects of IFE science and technology are described. [ABSTRACT FROM AUTHOR]

The international research community interested in the Laser Interferometric Space Antenna (LISA) program meets every two years to exchange scientific and technical information. From 28 June-2 July 2010, Stanford University hosted the 8th International LISA Symposium. The symposium was held on the campus of the SLAC National Accelerator Laboratory. Many of the foremost scientific and technological researchers in LISA and gravitational wave theory and detection presented their work and ideas. Over one hundred engineers and graduate students attended the meeting. The leadership from NASA and ESA research centers and programs joined the symposium. A total of 280 delegates participated in the 8th LISA Symposium, and enjoyed the scientific and social programs. The scientific program included 46 invited plenary lectures, 44 parallel talks, and 77 posters, totaling 167 presentations. The one-slide introduction presentation of the posters is a new format in this symposium and allowed graduate students the opportunity to talk in front of a large audience of scientists. The topics covered included LISA Science, LISA Interferometry, LISA PathFinder (LPF), LISA and LPF Data Analysis, Astrophysics, Numerical Relativity, Gravitational Wave Theory, GRS Technologies, Other Space Programs, and Ground Detectors. Large gravitational wave detection efforts, DECIGO, and LIGO were presented, as well as a number of other fundamental physics space experiments, with GP-B and STEP being examples. A public evening lecture was also presented at the symposium. Professor Bernard Schutz from the Albert Einstein Institute gave a general audience, multimedia presentation on `Gravitational waves: Listening to the music of spheres''. For more detailed information about the symposium and many presentation files, please browse through the website: http://www.stanford.edu/group/lisasymposium The Proceedings of the 8th International LISA Symposium are jointly published by Classical and Quantum Gravity (CQG) and Journal of Physics: Conference Series (JPCS). The plenary lectures are published in CQG, while most parallel talks and posters are being published in JPCS. At the recommendation of the science organization committee (SOC) other selected work from the conference will also appear in CQG. All papers in CQG have been screened through the journal''s regular peer review process. We gratefully acknowledge the support of the CQG and JPCS Publishers and staff for the publication of the proceedings. The symposium and proceedings are generously sponsored by L''Agenzia Spaziale Italiana, the California Institute of Technology, EADS Astrium Germany, the KACST Foundation Saudi Arabia, the LIGO collaboration, the Max-Planck Institute in Potsdam, Germany, NASA, and the National Science Foundation. Stanford University made very significant contributions through the Dean of Research Office, the Department of Applied Physics, the Department of Physics, the Hansen Experimental Physics Laboratory (HEPL), and the SLAC National Accelerator Laboratory. We thank the Stanford local organization committee (LOC), administration and professional staff, KACST engineers, and graduate students for their support of the symposium operations. LISA is one of the most tantalizing yet challenging scientific space missions ever. The 8th International LISA Symposium and publication of the proceedings contribute to its progress. Sasha Buchman and Ke-Xun Sun Stanford University Guest Editors [ABSTRACT FROM AUTHOR]

LISA is a joint space mission of the NASA and the ESA for detecting low-frequency gravitational waves in the band 10[?]5 to 1 Hz. In order to attain the requisite sensitivity for LISA, the laser frequency noise must be suppressed below the other secondary noises such as the optical path noise, acceleration noise, etc. This is achieved by the technique called time delay interferometry (TDI) in which the data are combined with appropriate time delays. In this paper we approximately compute the spacecraft orbits in the gravitational field of the Sun and Earth. We have written a numerical code which computes the optical links (time delays) in the general relativistic framework within an accuracy of [?]10 m, which is sufficient for TDI. Our computation of the optical links automatically takes into account the effects such as the Sagnac, Shapiro delay, etc. We show that by optimizing LISA orbits, and using the symmetries inherent in the configuration of LISA and in the physics, the residual laser noise in the modified first-generation TDI can be adequately suppressed. We demonstrate our results for some important TDI observables. [ABSTRACT FROM AUTHOR]

The article provides information on the benefits received by new members of the Electrochemical Society (ECS) in the U.S. Beginning September 2008, ECS members will have flexible online access to key research articles, as well as content of papers presented during meetings from the entire Digital Library of the organization. It states that the new package will provide ECS members with 100 full-text downloads from its journals and digital archives.

In ITER, magnetic fusion will explore the burning plasma regime. Because such burning plasma is sustained by its own fusion reactions, alpha particles need to be confined (Hazeltine 2010 Fusion Eng. Des. 7-9 85). New experiments using d(3He,p)α and d(d,p)t fusion reaction products were performed in JET. Fusion product loss was measured from MHD-quiescent plasmas with a charged particle activation probe installed at a position opposite to the magnetic field ion gradient drift (see figure 1)--1.77m above mid-plane--in the ceiling of JET tokamak. This new kind of escaping ion detector (Bonheure et al 2008 Fusion Sci. Technol. 53 806) provides for absolutely calibrated measurements. Both the mechanism and the magnitude of the loss are dealt with by this research. Careful analysis shows measured loss is in quantitative agreement with predictions from the classical orbit loss model. However, the comparison with simulated loss radial profile, although improved compared with previous studies in TFTR, Princeton, US (Zweben et al 2000 Nucl. Fusion 40 91), is not fully satisfactory and potential explanations for this discrepancy are examined. [ABSTRACT FROM AUTHOR]

Computational phantoms serve an important role in organ dosimetry and risk assessment performed at the National Aeronautics and Space Administration (NASA). A previous study investigated the impact on organ dose equivalents and effective doses from the use of the University of Florida hybrid adult male (UFHADM) and adult female (UFHADF) phantoms at differing height and weight percentiles versus those given by the two existing NASA phantoms, the computerized anatomical man (CAM) and female (CAF) (Bahadori et al 2011 Phys. Med. Biol. 56 1671-94). In the present study, the UFHADM and UFHADF phantoms of different body sizes were further altered to incorporate the effects of microgravity. Body self-shielding distributions are generated using the voxel-based ray tracer (VoBRaT), and the results are combined with depth dose data from the NASA codes BRYNTRN and HZETRN to yield organ dose equivalents and their rates for a variety of space radiation environments. It is found that while organ dose equivalents are indeed altered by the physiological effects ofmicrogravity, the magnitude of the change in overall risk (indicated by the effective dose) is minimal for the spectra and simplified shielding configurations considered. The results also indicate, however, that UFHADMand UFHADF could be useful in designing dose reduction strategies through optimized positioning of an astronaut during encounters with solar particle events. [ABSTRACT FROM AUTHOR]

A chaos-based cryptosystem for fractal image coding is proposed. The R'enyi chaotic map is employed to determine the order of processing the range blocks and to generate the keystream for masking the encoded sequence. Compared with the standard approach of fractal image coding followed by the Advanced Encryption Standard, our scheme offers a higher sensitivity to both plaintext and ciphertext at a comparable operating efficiency. The keystream generated by the R'enyi chaotic map passes the randomness tests set by the United States National Institute of Standards and Technology, and so the proposed scheme is sensitive to the key. [ABSTRACT FROM AUTHOR]

The article presents information on student travel grants and awarded student memberships offered by the U.S. Electrochemical Society (ECS). The ECS offers travel assistance to students presenting papers at ECS meetings. Awarded student memberships are offered to full-time students who are in their final two years of an undergraduate program or a graduate program in science, engineering or education. Included is a copy of the ECS awarded membership application.

Resources: Online schools video library GIREP Seminar: A seminar not a conference New Teaching Resource: Free living for teachers Space: NASA proposes MEER - Momentum Exchange Electrodynamic-Reboost Electronic Teaching Materials: Superconductivity motivates need for upper secondary curriculum subjects Gifted and Talented: Seminars seek challenges Space: Comet chasing Particle Physics: Playing with single electrons Physics on Stage: Teachers explore the meaning of life Physics on Stage: Greek national event Physics on Stage: Physics on the Slovak stage Physics on Stage: Clubbing in Germany Physics on Stage: The Sun's star performance Higher Education: Physics: so refreshing USA: Broadening the Base AAPT Summer Meeting: US teachers in good form Astronomy: High school astronomy in the Czech Republic Space: Express to Mars Particle Physics: Journey to the centre of the Earth? ASE 2004: Flight from the ASE Physics Songs: A powerful melody Teacher Training: European training looks for ideal model [ABSTRACT FROM AUTHOR]

Reports that the Electronics Division of the Electrochemical Society is offering travel grants to students presenting papers at the Society's 1999 Joint International Meeting in Honolulu, Hawaii.

Reports that the High Temperature Materials Division of the Electrochemical Society is offering travel grants to student members who are presenting papers at ECS Meetings.

Reports that the Physical Electrochemistry Division of the Electrochemical Society is offering travel grants to student members who are presenting papers at ECS Meetings.

Reports that the Dielectric Science and Technology Division of the Electrochemical Society is offering travel grants to students presenting papers at the Society's 1999 Joint International Meeting in Honolulu, Hawaii.

Reports that several of the Electrochemical Society's divisions are offering travel assistance to students presenting papers at Society Meetings.

Reports on the travel grants being offered by the Electrochemical Society (ECS) Electronic Division to students presenting papers at the Society's 189th meeting in Los Angeles, California on May 5-10, 1996. Application process; Deadline for applications.

Indirect drive converts high power laser light into x-rays using small high-Z cavities called hohlraums. X-rays generated at the hohlraum walls drive a capsule filled with deuterium–tritium (DT) fuel to fusion conditions. Recent experiments have produced fusion yields exceeding 50 kJ where alpha heating provides ~3×  increase in yield over PdV work. Closing the gaps toward ignition is challenging, requiring optimization of the target/implosions and the laser to extract maximum energy. The US program has a three-pronged approach to maximize target performance, each closing some portion of the gap. The first item is optimizing the hohlraum to couple more energy to the capsule while maintaining symmetry control. Novel hohlraum designs are being pursued that enable a larger capsule to be driven symmetrically to both reduce 3D effects and increase energy coupled to the capsule. The second issue being addressed is capsule stability. Seeding of instabilities by the hardware used to mount the capsule and fill it with DT fuel remains a concern. Work reducing the impact of the DT fill tubes and novel capsule mounts is being pursed to reduce the effect of mix on the capsule implosions. There is also growing evidence native capsule seeds such as a micro-structure may be playing a role on limiting capsule performance and dedicated experiments are being developed to better understand the phenomenon. The last area of emphasis is the laser. As technology progresses and understanding of laser damage/mitigation advances, increasing the laser energy seems possible. This would increase the amount of energy available to couple to the capsule, and allow larger capsules, potentially increasing the hot spot pressure and confinement time. The combination of each of these focus areas has the potential to produce conditions to initiate thermo-nuclear ignition. [ABSTRACT FROM AUTHOR]

Objective: Rises in the incidence of pressure ulcers are increasingly prevalent in an aging population. Pressure ulcers are painful, are associated with increased morbidity and mortality, increase the risk for secondary infections and inpatient stay, and adds $26.8 billion annually to the healthcare costs of the USA. Evidence suggests that a change in the bioimpedance of living tissue in response to continuous local contact pressure can be a useful indicator for the onset of pressure injuries. Approach: Thirty-five Sprague Dawley rats were subjected to various skin pressures for differing periods of time via a surgically inserted steel disk and an externally applied magnet. Contact pressure and bioimpedance were measured and correlated with tissue loading intensity and compared to clinical ulcer grading. Main results: Moderate relationships between bioimpedance changes and tissue loading intensity were found. Stronger correlations were found by utilizing a combination of bioimpedance and phase angle. Thresholds were applied to the bioimpedance parameters and the usefulness of bioimpedance in classifying different ulcer stages is demonstrated. Significance: These results indicate that bioimpedance may be useful as an early indicator of pressure ulcer formation and has practical significance in the development of early pressure injury detection devices. [ABSTRACT FROM AUTHOR]

Lung densitometry is being frequently adopted in CT-based emphysema quantification, yet known to be affected by the choice of reconstruction kernel. This study presents a two-step deep learning architecture that enables accurate normalization of reconstruction kernel effects on emphysema quantification in low-dose CT. Deep learning is used to convert a CT image of a sharp kernel to that of a standard kernel with restoration of truncation artifacts and smoothing-free pixel size normalization. We selected 353 scans reconstructed by both standard and sharp kernels from four different CT scanners from the United States National Lung Screening Trial program database. A truncation artifact correction model was constructed with a combination of histogram extrapolation and a deep learning model trained with truncated and non-truncated image sets. Then, we performed frequency domain zero-padding to normalize reconstruction field of view effects while preventing image smoothing effects. The kernel normalization model has a U-Net based architecture trained for each CT scanner dataset. Three lung density measurements including relative lung area under 950 HU (RA950), lower 15th percentile threshold (perc15), and mean lung density were obtained in the datasets from standard, sharp, and normalized kernels. The effect of kernel normalization was evaluated with pair-wise differences in lung density metrics. The mean of pair-wise differences in RA950 between standard and sharp kernel reconstructions was reduced from 10.75% to  −0.07% using kernel normalization. The difference for perc15 decreased from  −31.03 HU to  −0.30 HU after kernel normalization. Our study demonstrated the feasibility of applying deep learning techniques for normalizing CT kernel effects, thereby reducing the kernel-induced variability in lung density measurements. The deep learning model could increase the accuracy of emphysema quantification, thereby allowing reliable surveillance of emphysema in lung cancer screening even when follow-up CT scans are acquired with different reconstruction kernels. [ABSTRACT FROM AUTHOR]

A cloud-based software, VirtualDose-IR (Virtual Phantoms Inc., Albany, New York, USA), designed to report organ doses and effective doses for a diverse patient population from interventional radiology (IR) procedures has been developed and tested. This software is based on a comprehensive database of Monte Carlo-generated organ dose built with a set of 21 anatomically realistic patient phantoms. The patient types included in this database are both male and female people with different ages reflecting reference adults, obese people with different BMIs and pregnant women at different gestational stages. Selectable parameters such as patient type, tube voltage, filtration thickness, beam direction, field size, and irradiation site are also considered in VirtualDose-IR. The software has been implemented using the ‘Software as a Service (SaaS)’ delivery concept permitting simultaneous multi-user, multi-platform access without requiring local installation. The patient doses resulting from different target sites and patient populations were reported using the VirtualDose-IR system. The patient doses under different source to surface distances (SSD) and beam angles calculated by VirtualDose-IR and Monte Carlo simulations were compared. For most organs, the dose differences between VirtualDose-IR results and Monte Carlo results were less than 0.3 mGy at 15 000 mGy * cm2 kerma-area product (KAP). The organ dose results were compared with measurement data previously reported in literatures. The doses to organs that were located within the irradiation field match closely with experimental measurement data. The differences in the effective dose values between calculated using VirtualDose-IR and those measured were less than 2.5%. The dose errors of most organs between VirtualDose-IR and literature results were less than 40%. These results validate the accuracy of organ doses reported by VirtualDose-IR. With the inclusion of pre-specified clinical IR examination parameters (such as beam direction, target location, field of view and beam quality) and the latest anatomically realistic patient phantoms in Monte Carlo simulations, VirtualDose-IR provides users with accurate dose information in order to systematically compare, evaluate, and optimize IR plans. [ABSTRACT FROM AUTHOR]

Cardiovascular disease is the leading cause of mortality in the United States. Peripheral artery disease (PAD) affects a substantial portion of the elderly population (>70 years). PAD can be symptomatic or asymptomatic, and treatment is directed towards improving functional vessel patency and limb salvage. Revascularization surgical treatments are needed in some cases, and it is not always possible to use autologous veins for vascular grafting. In this case, synthetic materials may be used. Synthetic materials such as expanded polytetrafluoroethylene (ePTFE) and poly (ethylene terephthalate) (Dacron) have been used. These materials are much stiffer compared to normal arterial vessels so developing alternative materials is an active area of research. One such potential material is a p olyvinyl alcohol cryogel reinforced arterial model (PRAM). In this study we used shear wave elastography (SWE) techniques to compare the mechanical behavior of excised aortas and anastomoses formed between the aortas and the Dacron, ePTFE, and PRAM materials. Different initial longitudinal strains (0%–40%) and transmural pressures (20–180 mmHg) were used to test a wide range of parameters that are within physiological ranges. We found that the PRAM materials had similar mechanical behavior in terms of group velocity measured in the vessel wall with respect to the excised aortas compared to the Dacron and ePTFE that had higher values of group velocity. The ratios of the group velocity for the PRAM material with respect to the aortas ranged from 0.83 to 1.13 where the Dacron and ePTFE had ranges of 1.12–2.22 and 1.91–3.10 for the same stretch and pressure ranges. The PRAM materials provide an alternative vascular material with better mechanical matching with excised aortas. [ABSTRACT FROM AUTHOR]

Using the Very Long Baseline Array, we have made astrometric observations of the binary pulsar B1913+16 spanning an 18-month period in 2014–2015. From these observations we make the first determination of the annual geometric parallax of B1913+16, measuring mas (68% confidence interval). The inferred parallax probability distribution differs significantly from a Gaussian. Using our parallax measurement and prior information on the spatial and luminosity distributions of the millisecond pulsar population, we infer a distance of kpc, which is significantly closer than the 9.8 ± 3.1 kpc suggested by the pulsar’s dispersion measure (DM) and analyses of the ionized interstellar medium. While the relatively low significance of the parallax detection (∼3σ) currently precludes an improved test of general relativity using the orbital decay of PSR B1913+16, ongoing observations with improved control of systematic astrometric errors could reach the 10% distance uncertainty required for this goal. The proper motion measured by our Very Long Baseline Interferometry astrometry differs substantially from that obtained by pulsar timing, a discrepancy that has also been found between the proper motion measurements made by interferometers and pulsar timing for some other pulsars, which we speculate is the result of timing noise or DM variations in the timing data set. Our parallax and proper motion measurements yield a transverse velocity of km s−1 in the solar reference frame. Analysis incorporating galactic rotation and solar motion finds that the space velocity of the pulsar relative to its standard of rest has a component km s−1 perpendicular to the galactic plane and components on the order of 100 km s−1 parallel to the galactic plane. [ABSTRACT FROM AUTHOR]

The United States Transuranium and Uranium Registries’ (USTUR) whole-body donor (Case 1031) was exposed to an acute inhalation of uranium hexafluoride (UF6) produced from an explosion at a uranium processing plant 65 years prior to his death. The USTUR measurements of tissue samples collected at the autopsy indicated long-term retention of inhaled slightly enriched uranium material (0.85% 235U) in the deep lungs and thoracic lymph nodes. In the present study, the authors combined the tissue measurement results with historical bioassay data, and analysed them with International Commission on Radiological Protection (ICRP) respiratory tract models and the ICRP Publication 69 systemic model for uranium using maximum likelihood and Bayesian statistical methods. The purpose of the analysis was to estimate intakes and model parameter values that best describe the data, and evaluate their effect on dose assessment. The maximum likelihood analysis, which used the ICRP Publication 66 human respiratory tract model, resulted in a point estimate of 79 mg of uranium for the occupational intake composed of 86% soluble, type F material and 14% insoluble, type S material. For the Bayesian approach, the authors applied the Markov Chain Monte Carlo method, but this time used the revised human respiratory tract model, which is currently being used by ICRP to calculate new dose coefficients for workers. The Bayesian analysis estimated that the mean uranium intake was 160 mg, and calculated the case-specific lung dissolution parameters with their associated uncertainties. The parameters were consistent with the inhaled uranium material being predominantly soluble with a small but significant insoluble component. The 95% posterior range of the rapid dissolution fraction (the fraction of deposited material that is absorbed to blood rapidly) was 0.12 to 0.91 with a median of 0.37. The remaining fraction was absorbed slowly, with a 95% range of 0.000 22 d−1 to 0.000 36 d−1 and a median of 0.000 31 d−1. The effective dose per unit intake calculated using the dissolution parameters derived from the maximum likelihood and the Bayesian analyses was higher than the current ICRP dose coefficient for type F uranium by a factor of 2 or 7, respectively; the higher value of the latter was due to use of the revised respiratory tract model. The dissolution parameter values obtained here may be more appropriate to use for radiation protection purposes when individuals are exposed to a UF6 mixture that contains an insoluble uranium component. [ABSTRACT FROM AUTHOR]

Based on three-dimensional (3D) topography measurements on correlation cells, the National Institute of Standards and Technology (NIST) has developed the ‘NIST Ballistics Identification System (NBIS)’ aimed at accurate ballistics identifications and fast ballistics evidence searches. The 3D topographies are divided into arrays of correlation cells to identify ‘valid correlation areas’ and eliminate ‘invalid correlation areas’ from the matching and identification procedure. A ‘congruent matching cells’ (CMC)’ method using three types of identification parameters of the paired correlation cells (cross correlation function maximum CCFmax, spatial registration position in x–y and registration angle θ) is used for high accuracy ballistics identifications. ‘Synchronous processing’ is proposed for correlating multiple cell pairs at the same time to increase the correlation speed. The proposed NBIS can be used for correlations of both geometrical topographies and optical intensity images. All the correlation parameters and algorithms are in the public domain and subject to open tests. An error rate reporting procedure has been developed that can greatly add to the scientific support for the firearm and toolmark identification specialty, and give confidence to the trier of fact in court proceedings. The NBIS is engineered to employ transparent identification parameters and criteria, statistical models and correlation algorithms. In this way, interoperability between different ballistics identification systems can be more easily achieved. This interoperability will make the NBIS suitable for ballistics identifications and evidence searches with large national databases, such as the National Integrated Ballistic Information Network in the United States. [ABSTRACT FROM AUTHOR]

Assessment of radiation absorbed dose to internal organs of the body from the intake of radionuclides, or in the medical setting through the injection of radiopharmaceuticals, is generally performed based upon reference biokinetic models or patient imaging data, respectively. Biokinetic models estimate the time course of activity localized to source organs. The time-integration of these organ activity profiles are then scaled by the radionuclide S-value, which defines the absorbed dose to a target tissue per nuclear transformation in various source tissues. S-values are computed using established nuclear decay information (particle energies and yields), and a parameter termed the specific absorbed fraction (SAF). The SAF is the ratio of the absorbed fraction-fraction of particle energy emitted in the source tissue that is deposited in the target tissue-and the target organ mass. While values of the SAF may be computed using patient-specific or individual-specific anatomic models, they have been more widely available through the use of computational reference phantoms. In this study, we report on an extensive series of photon SAFs computed in a revised series of the University of Florida and the National Cancer Institute pediatric reference phantoms which have been modified to conform to the specifications embodied in the ICRP reference adult phantoms of Publication 110 (e.g. organs modeled, organ ID numbers, blood contribution to elemental compositions). Following phantom anatomical revisions, photon radiation transport simulations were performed using MCNPX v2.7 in each of the ten phantoms of the series-male and female newborn, 1 year old, 5 year old, 10 year old, and 15 year old-for 60 different tissues serving as source and/or target regions. A total of 25 photon energies were considered from 10 keV to 10 MeV along a logarithm energy grid. Detailed analyses were conducted of the relative statistical errors in the Monte Carlo target tissue energy deposition tallies at low photon energies and over all energies for source-target combinations at large intra-organ separation distances. Based on these analyses, various data smoothing algorithms were employed, including multi-point weighted data smoothing, and log-log interpolation at low energies (1 keV and 5 keV) using limiting SAF values based upon target organ mass to bound the interpolation interval. The final dataset is provided in a series of ten electronic supplemental files in MS Excel format. The results of this study were further used as the basis for assessing the radiative component of internal electron source SAFs as described in our companion paper (Schwarz et al 2021) for this same pediatric phantom series.

This paper investigates a quality assurance (QA) phantom specially designed to verify the accuracy of dose distributions and monitor units (MU) calculated by clinical treatment planning optimization systems and by the Monte Carlo method for intensity-modulated radiotherapy (IMRT). The QA phantom is a PMMA cylinder of 30 cm diameter and 40 cm length with various bone and lung inserts. A procedure (and formalism) has been developed to measure the absolute dose to water in the PMMA phantom. Another cylindrical phantom of the same dimensions, but made of water, was used to confirm the results obtained with the PMMA phantom. The PMMA phantom was irradiated by 4, 6 and 15 MV photon beams and the dose was measured using an ionization chamber and compared to the results calculated by a commercial inverse planning system (CORVUS, NOMOS, Sewickley, PA) and by the Monte Carlo method. The results show that the dose distributions calculated by both CORVUS and Monte Carlo agreed to within 2% of dose maximum with measured results in the uniform PMMA phantom for both open and intensity-modulated fields. Similar agreement was obtained between Monte Carlo calculations and measured results with the bone and lung heterogeneity inside the PMMA phantom while the CORVUS results were 4% different. The QA phantom has been integrated as a routine QA procedure for the patient's IMRT dose verification at Stanford since 1999.

VIP-Man is a whole-body anatomical model newly developed at Rensselaer from the high-resolution colour images of the National Library of Medicine's Visible Human Project. This paper summarizes the use of VIP-Man and the Monte Carlo method to calculate specific absorbed fractions from internal electron emitters. A specially designed EGS4 user code, named EGS4-VLSI, was developed to use the extremely large number of image data contained in the VIP-Man. Monoenergetic and isotropic electron emitters with energies from 100 keV to 4 MeV are considered to be uniformly distributed in 26 organs. This paper presents, for the first time, results of internal electron exposures based on a realistic whole-body tomographic model. Because VIP-Man has many organs and tissues that were previously not well defined (or not available) in other models, the efforts at Rensselaer and elsewhere bring an unprecedented opportunity to significantly improve the internal dosimetry.