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A free triangular jet (TJ1) and its counterpart initially passing a short circular chamber (TJ2) are numerically modeled using large eddy simulation (LES). This paper compares the near-field characteristics of the two jets in detail. To enable some necessary experimental validations, the LES conditions of TJ1 and TJ2 are taken to be identical to those measured by Xu et al. (Sci. China Phys. 56 1176 (2013)) and England et al. (Exp. Fluids. 48 69 (2010)), respectively. The LES predictions are found to agree well with those measurements. It is demonstrated that a strong swirl occurs near the chamber inlet plane for the TJ2 flow. At the center of the swirl, there is a cluster of three sink foci, where each focus is aligned midway between the original triangular apexes. In the vortex skeleton constructed from the time-averaged flow field, the vortices arising from the foci are helically twisted around the core of the jet. As the flow passes through the chamber, the foci merge to form a closed-loop "bifurcation line", which separates the inward swirling flow and the outward oscillating jet. This global oscillation is regarded as a source node near the centerline of the chamber. If the chamber is removed for a "free" jet, i.e., TJ1, a cluster of three pairs of counter-rotating foci is produced and the net swirl circulation is zero, so the overall oscillation of the jet does not occur. [ABSTRACT FROM AUTHOR]

Poiseuille flow and thermal transpiration of a rarefied gas between plane parallel walls with nonuniform surface properties are studied on the basis of kinetic theory. Specifically, one of the walls is a diffuse reflection boundary, and the other wall is a Maxwell-type boundary whose accommodation coefficient has a periodic distribution in the direction perpendicular to the flow. The behavior of the gas is studied on the basis of the linearized Bhatnagar–Gross–Krook–Welander model of the Boltzmann equation. The extended integral equation for the macroscopic flow velocity is derived for the analysis at large Knudsen numbers, and is numerically solved. Features in the dependence of the mass flow rate on the distribution of the accommodation coefficient observed in the previous study (Doi 2015 ASME J. Fluids. Eng. 137 101103) were found to hold over a quite wide range of the Knudsen number up to 1000. A successive approximation method of the solution for a large Knudsen number is numerically tested using the integral equation. [ABSTRACT FROM AUTHOR]

This paper studies the mortality and cancer morbidity of the 470 male workers involved in tackling the 1957 Sellafield Windscale fire or its subsequent clean-up. Workers were followed up for 50 years to 2007, extending the follow-up of a previously published cohort study on the Windscale fire by 10 years. The size of the study population is small, but the cohort is of interest because of the involvement of the workers in the accident. Significant excesses of deaths from diseases of the circulatory system (standardised mortality ratio (SMR) = 120, 95% CI = 103-138; 194 deaths) driven by ischaemic heart disease (IHD) (SMR = 133, 95% CI = 112-157, 141 deaths) were found when compared with the population of England and Wales but not when compared with the population of Northwest England (SMR = 105, 95% CI = 90-120 and SMR = 115, 95% CI = 97-136 respectively). When compared with those workers in post at the time of the fire but not directly involved in the fire the mortality rate from IHD among those involved in tackling the fire was raised but not statistically significantly (rate ratio (RR) = 1.11, 95% CI = 0.92-1.33). A RR of 1.11 is consistent with an excess relative risk of 0.65 Sv [?] 1 as reported in an earlier study of non-cancer mortality in the British Nuclear Fuels plc cohort of which these workers are a small but significant part. There was a statistically significant difference in lung cancer mortality (RR = 2.18, 95% CI = 1.05-4.52) rates between workers who had received higher recorded external doses during the fire and those who had received lower external doses. Comparison of the mortality rates of workers directly involved in the accident with workers in post, but not so involved, showed no significant differences overall. On the basis of the use of a propensity score the average effect of involvement in the Windscale fire on all causes of death was [?] 2.13% (se = 3.64%, p = 0.56) though this difference is not statistically significant. The average effect of involvement in the Windscale fire was [?] 5.53% (se = 3.81, p = 0.15) for all cancers mortality and 6.60% (se = 4.03%, p = 0.10) for IHD mortality though neither figure was statistically significant. This analysis of the mortality and cancer morbidity experience of those Sellafield workers involved in the 1957 Windscale fire does not reveal any measurable effect of the fire upon their health. Although this study has low statistical power for detecting small adverse effects, due to the relatively small number of workers, it does provide reassurance that no significant health effects are associated with the 1957 Windscale fire even after 50 years of follow-up. [ABSTRACT FROM AUTHOR]

The article informs that lecturers Judith Hillier and Sian Owen from University of Oxford's departments of education and physics, respectively, have joined hands with physics teachers from local schools to develop the Oxfordshire Schools Physics Partnership. It informs that the partnership has three aims including enriching the physics-learning experience of pupils, encouraging more girls to choose physics at university, and supporting physics teaching. It also informs that schools would bring teams of four or five pupils and participate in a number of activities.

The author offers information on the 13th International Workshop onH-mode Physics and Transport Barriers held in Lady Margaret Hall College in Oxford, England in October 2011. He mentions that the series of meetings in the workshop were based on the study of transport barriers in fusion plasmas. He also informs that several topics have been discussed in the workshop including transport barrier control and plasma performance, H-mode transition physics and plasma turbulence.

This issue of Physiological Measurement follows the successful 10th International Conference on Electrical Impedance Tomography. The conference was hosted by the University of Manchester''s School of Mathematics and organized by Bill Lionheart, Richard Bayford from Middlesex University and Eung Je Woo of Kyung Hee University. A combined workshop on electromagnetic inverse problems was also held at the same time, organized by Olive Dorn and Bill Lionheart. This workshop shared plenary lectures and some sessions. One of the plenaries was by Mark Nelson on electrosensory data acquisition and signal processing strategies in electric fish; perhaps the first time the medical EIT community had shared a conference with experts on the variety of EIT that occurs naturally in some fish. Indeed some electrosensing fish were present at the meeting and an aquarium especially set up in the School of Mathematics. The conference provided a platform for investigators in all aspects of EIT to engage in common areas of interest whilst also giving an opportunity for the community to broaden its outlook in the areas of clinical applications and new technologies associated with EIT. It also provided a link to researchers working on the mathematical aspect of inverse problems that limit the development of EIT for clinical applications. This upholds the tradition of successful conferences on biomedical applications of EIT, as with the previous jointly organized conference on electrical impedance tomography in 2008, co-hosted by the Thayer School of Engineering at Dartmouth College and organized by Alex Hartov of Dartmouth and Eung Je Woo. This special issue of Physiological Measurement contains articles stemming from discussion and feedback during the conference on EIT research areas. The conference was also an opportunity for new researchers to join the community and propose recent innovations. A total of 84 oral papers were presented and all authors were invited to prepare new peer-reviewed papers for inclusion in this issue. The manuscripts were put through a careful review process before a total of 12 were accepted covering an important range of topics. The articles included in this year''s special issue clearly reflect the continuing interest in EIT covering a wide range of clinical applications that were strongly represented at the conference. These included brain function, breast imaging, the thorax, and a new target: the prostate. It is important that researchers do not neglect the challenges that clinical applications of bio-impedance and EIT present as there are still many technical difficulties that the technology needs to overcome in order to provide valuable clinical tools. However, there are promising signs that these tools are close to realization, particularly for thorax imaging. This was clear as the most popular clinical application at the conference was a special session organized by Inez Frerichs, which provided an invaluable forum for clinical practitioners and EIT researchers to exchange ideas. As EIT continues to provide researchers with new challenges, the high quality of the research articles in this special issue is clear evidence of the significant advances in the field. [ABSTRACT FROM AUTHOR]

In the earlier studies of the Liu et al (2015 Intersecting chord method for minimum zone evaluation of roundness deviation using Cartesian coordinate data Precis. Eng. 42 242–52, 2016 Minimum circumscribed circle and maximum inscribed circle of roundness deviation evaluation with intersecting chord method IEEE Trans. Instrum. Meas. 65 2787–96), the intersecting chords method was proposed for modeling roundness and sphericity deviations. Because cylindricity deviation is partially associated with both deviations, this study focuses on the measurement and evaluation of cylindricity deviations using the intersecting chords method in the Cartesian coordinate system. Combined with the geometric structure of a cylinder, the measurement method of the cylindricity deviation in Cartesian coordinates is introduced, and the cylindricity measurement is conducted by multi-section sampling, axis fitting, and spatial projection. Based on this, the intersecting chords method is employed to construct models for the cylindricity deviation evaluation using the point coordinates obtained from the cylindricity measurements, including minimum circumscribed cylindricity, maximum inscribed cylindricity, and minimum zone cylindricity. The core of the intersecting chords method is using a chord instead of a curve as the characteristic element of the evaluation model. Moreover, the cross structure produced by the intersecting chords can control the position of the reference form and obtain the center of the evaluation model accurately. For the cylindricity deviation, the intersecting chords method not only reduces the modeling difficulty but also improves the evaluation accuracy. Moreover, the availability and validity of the modeling method are further verified by the experimental data obtained from coordinate measuring machines, and the results show that the research study is useful for developing measurement instruments and manufacturing equipment having large cylindrical parts. [ABSTRACT FROM AUTHOR]

This paper summarises work undertaken on behalf of the Environment Agency for England to quantify uncertainties resulting from internal exposures to a number of radionuclides considered significant because of their anthropogenic origin, namely: 238U, 226Ra, 239Pu, 241Am, 137Cs, 90Sr, 131I, 129I and 3H. Uncertainties in the biokinetic models that are used to calculate the retention and excretion of radionuclides are derived in order to calculate distributions of effective dose per unit intake following their inhalation or ingestion by members of the UK public. The central values and ranges of the distributions are used to inform the derivation of uncertainty factors (UFs) for the different dose coefficients, which can be used to assess reliability. These represent uncertainties inherent in the structures of the biokinetic models and their parameter values. The inferred UF values are typically around 2–3 for ingestion and 2–6 for inhalation for all age groups, and are comparable to UF values inferred from published studies. It is instructive to consider these ranges alongside the likely levels of exposure that are expected from the radionuclides considered (the microsievert range) and the dose limit of planned exposures for members of the public (1000 μSv). [ABSTRACT FROM AUTHOR]

The multidisciplinary two-day Nano Meets Spectroscopy (NMS) event was held at the National Physical Laboratory (NPL), Teddington, UK, in September 2011. The event was planned from the outset to be at the interface of several areas--in particular, spectroscopy and nanoscience, and to bring together topics and people with different approaches to achieving common goals in biomolecular science. Hence the meeting cut across traditional boundaries and brought together researchers using diverse techniques, particularly fluorescence and Raman spectroscopy. Despite engaging common problems, these techniques are frequently seen as mutually exclusive with the two communities rarely interacting at conferences. The meeting was widely seen to have lived up to its billing in good measure. It attracted the maximum capacity of ~120 participants, including 22 distinguished speakers (9 from outside the UK), over 50 posters and a vibrant corporate exhibition comprising 10 leading instrument companies and IOP Publishing. The organizers were Professor David Birch (Chair), Dr Karen Faulds and Professor Duncan Graham of the University of Strathclyde, Professor Cait MacPhee of the University of Edinburgh and Dr Alex Knight of NPL. The event was sponsored by the European Science Foundation, the Institute of Physics, the Royal Society of Chemistry, NPL and the Scottish Universities Physics Alliance. The full programme and abstracts are available at http://sensor.phys.strath.ac.uk/nms/program.php. The programme was quite ambitious in terms of the breadth and depth of scope. The interdisciplinary and synergistic concept of ''X meets Y'' played well, cross-fertilization between different fields often being a source of inspiration and progress. Fluorescence and Raman spectroscopy provided the core, but the meeting had little repetition and also attracted contributions on more specialist techniques such as CARS, super-resolution, single molecule and chiral methods. In terms of application the event bridged as far as medical application of nanotechnologies. It could have turned out that such a hotchpotch produced an incoherent event that lacked direction and focus, but in truth, as the feedback showed, the delegates revelled in the diversity and depth of quality. Excellent speakers, the common application to biomolecules and common language of spectroscopy were probably the reasons why things worked out so well. I am delighted to bring together in this special feature in Measurement Science and Technology a selection of contributions from the meeting and I thank all the authors for their excellent contributions. Included are papers on nanoparticles, plasmonics, sensing and imaging. This special feature, and indeed similar meetings in the future, will undoubtedly help sustain the ''nanomeeters'' message of NMS. [ABSTRACT FROM AUTHOR]

This paper aims to describe in basic terms how the different types of ion traps work, giving some examples of their use. It then discusses some recent 'exotic' designs of ion traps and shows how they are optimized for particular experiments. Recent work at Imperial College London is used to illustrate some of the ideas introduced in this paper. [ABSTRACT FROM AUTHOR]

Conference Photo The contribution that a Physicist can make to Tribology will be greatly increased by effective and enlightened collaboration with the chemist, metallurgist and engineer. David Tabor (1913-2005) The first meeting of the Institute of Physics Tribology Group was held at Cranfield, UK, in 1980 entitled ''Tribology: Contrasts in Frictional Processes''. The first chair of the Group was David Tabor who subsequently edited the proceedings of the 10th anniversary celebration of the formation of the Group which was held in Stratford-upon-Avon in 1991 and published by this journal as a special issue in 1992. This Special Cluster celebrates the continuation of this thriving Group and the work of some of our leading tribologists in the area who have contributed to the Group meetings in recent years. In particular, we are greatly pleased to have papers from young researchers in the field who will take this subject forward in different directions in the coming decades. In 2000, due to popular demand, the Tribology Group was active in securing the reprint of Tabor''s book The Hardness of Metals, originally published by Clarendon Press in 1951, and a very special memory for the Group was his presence at a one day event at Robinson College in Cambridge in July 2000 where, with characteristic humility and warmth, he asked the Tribology Group members present on the day to sign the blank page at the front of the book as his special memento of the event. He also gave a very illuminating account of his early research career. A tribute to David Tabor, who passed away in November 2005, was given in the opening address of the 25th anniversary meeting by Brian Briscoe, who described the importance of his seminal contributions to the subject which laid the foundation stones in our understanding of contact between solids, friction of metals and non-metals, frictional temperature rise, boundary lubrication and the science of adhesion and sliding wear. Today, 25 years on, tribology, as Tabor anticipated above, is a very different subject, now with significant current interest in contact mechanics at the nano level and the interaction with corrosion and other chemical environments. The 25th anniversary meeting held in February 2006 included presentations in these areas, marking the milestones in the scientific developments in tribology during the past 25 years and was followed by a celebratory dinner in the headquarters of the Institute of Physics at Portland Place in London. Thus, the papers in this Special Cluster of Journal of Physics D: Applied Physics celebrate the interdisciplinarity in the subject and some new horizons, authored by individuals who have contributed to IOP Tribology Group meetings in recent years. We are very grateful to the organizers of the 25th anniversary meeting, Mark Rainforth and Philip Shipway, and to the Institute of Physics for sponsorship of the reception on the day. We look forward to this subject moving in diverse directions in the coming years, and to the continuation of our lively and entertaining one day meeting series, where through ''human tribology'', i.e. friction through debate and argument with some of our colleagues, tempered by the lubricating good humour of other colleagues, we progress this subject forward. [ABSTRACT FROM AUTHOR]

Belfast: On the next level above Galileo Wales: 2nd All Wales Physics Teachers Meeting England: Good afternoon Natural Philosphers... Communication: Posters win prizes Careers: Physics On Course 2004 Visits: Refreshing Physics Sport: Cheating at baseball Physics on Stage: Polish performance Space: Forces that affect GPS satellites New Zealand: It's not All Black News these days New Initiatives: NOISE Physics on Stage 3: Lively stars heading for ESA [ABSTRACT FROM AUTHOR]

INTERVIEW Physics can fascinate the public Jim Al-Khalili is a professor of theoretical physics at the University of Surrey, UK, where he also holds a chair in public engagement in science. David Smith spoke to him about being an academic and a communicator. [ABSTRACT FROM AUTHOR]

INTERVIEW Engineering beats Pisa's problem John Burland has been professor of soil mechanics at Imperial College London for 20 years and is recognized as a distinguished figure in geotechnical engineering. David Smith talks to him about his work. [ABSTRACT FROM AUTHOR]

INTERVIEW Using sci-fi to promote physics Robert Flack, a research fellow at University College London, talks to David Smith about science writing and the consequences for physicists of books like Angels and Demons. [ABSTRACT FROM AUTHOR]

Radiation streaming down gaps between shielding windows and walls of radiotherapy treatment rooms has been investigated. The calculations were based on a cobalt-60 source and were performed with the computer code RANKERN. The dose rate near the exit of the gap on the cold side of the window was calculated as the sum of contributions from direct line of sight and radiation scattered off the faces of the gap, using albedo data. The RANKERN code employs point kernel equations which are solved by a stochastic integration method. The paper demonstrates that although for a single element window small gaps could lead to significant leakage of radiation, for a double or triple element window, even a gap of ten millimetres would result in a dose rate no greater than that through the surrounding concrete.