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Background: A proton therapy system with 190° gantries uses robotic couch rotations to change the treatment beam laterality. Couch rotations are typically validated clinically with post‐rotation radiographic imaging. Aims: This study assesses the specificity and sensitivity of a commercial 3D surface imaging system, AlignRT (Vision RT, London UK) for validating couch rotations. Materials & Methods: In clinical operation, a reference surface image of the patient is acquired after radiographic setup with couch at 270°, perpendicular to the gantry axis of rotation. The couch is then rotated ±90° to a typical treatment angle, and AlignRT reports a 3D displacement vector. Patient motion, changes in patient surface, non‐coincidence between AlignRT and couch isocenter, and mechanical couch run‐out all contribute to the 3D vector magnitude. To assess AlignRT sensitivity in detecting couch run‐out, volunteers were positioned orthogonal to the proton gantry and reference surface images were captured without x‐ray localization. Subjects were repeatedly rotated ±90⁰ to typical treatment angles and displacement vectors were recorded. Additionally, measurements were performed in which intentional translations of 2, 4, 6, and 8 mm were combined with the intended isocentric rotations. Data sets were collected using a phantom; subjects with a thoracic isocenter and no immobilization; and subjects with a cranial isocenter and thermoplastic immobilization. A total of 300 rotations were measured. Results: During isocentric rotations, the mean AlignRT displacement vectors for the phantom, immobilized, and non‐immobilized volunteers were 0.1 ± 0.1 mm, 0.8 ± 0.1 mm, and 1.1 ± 0.2 mm respectively. 95% of the AlignRT measurements for the immobilized and non‐immobilized subjects were within 1 mm and 2 mm of the actual displacement respectively. Discussion: After characterizing the accuracy using phantoms and volunteers, we have shown that a three‐pod surface imaging system can be used to identify gross non‐isocentric patient rotations. Significant positional deviations, either due to improper couch rotation or patient motion, should be followed by radiographic imaging and repositioning. Conculsion: AlignRT can be used to verify patient positioning following couch rotations that are applied after the initial x‐ray guided patient setup. Using a three‐pod AlignRt system, positional deviations exceeding 4 mm were flagged with sensitivity and specificity of 90% and 100% respectively. [ABSTRACT FROM AUTHOR]

Featured Application: This opinion piece discusses the limitations of the current cytotoxic dosing methods and how advanced body measurement techniques could be used by oncology practitioners to determine cytotoxic chemotherapy dosages for patients, regardless of their body size. Within chemotherapy, estimates of a patient's body surface area (BSA) are used to calculate drug dosages. However, the use of BSA for calculating chemotherapy dosage has been heavily criticised in previous literature, with potentially significant implications for the effectiveness and toxicity of treatment. BSA has been found to be a poor indicator of optimal drug exposure that does not account for the complex processes of cytotoxic drug distribution and elimination. In addition, differences in BSA estimates between existing formulae have been shown to be so large that they can affect patients' mortality, particularly in patients with atypical body types. This uncertainty associated with BSA prediction may decrease the confidence of practitioners when determining chemotherapy dosages, particularly with regards to the risk of excess toxicity from over-dosing, or a reduced anti-cancer effect due to under-dosing. The use of national dose-banding in the UK may in some cases account for possible inaccuracies, but the threshold of variance in this case is small (+/−6%). Advanced body measurement techniques, utilising digital tools such as three-dimensional (3D) surface imaging, capture accurate external dimensions and detailed shape characteristics of the human body. Measures of body shape describe morphological variations that cannot be identified by traditional anthropometric techniques and improve the prediction of total body fat and distribution. It is our view that the use of advanced body measurement techniques can provide practitioners with tools for prescribing chemotherapy dosages that are valid for individuals, regardless of their body type. [ABSTRACT FROM AUTHOR]

Purpose: To propose a specific surface guided stereotactic radiotherapy (SRT) treatment procedure with open-face mask immobilization and evaluate the initial clinical experience in improving setup accuracy.Methods and Materials: The treatment records of 48 SRT patients with head lesions were retrospectively analyzed. For each patient, head immobilization was achieved with a double-shell open-face mask. The anterior shell was left open to expose the forehead, nose, eyes and cheekbones. The exposed facial area was used as region-of-interest for surface tracking by AlignRT (VisionRT Inc, UK). The posterior shell provided a sturdy and personalized headrest. Patient initial setup was guided by 6DoF real-time deltas (RTD) using the reference surface obtained from the skin contour delineated on the planning CT images. The endpoint of initial setup was 1 mm in translational RTD and 1 degree in rotational RTD. CBCT guidance was performed to derive the initial setup errors, and couch shifts for setup correction were applied prior to treatment delivery. CBCT couch shifts, AlignRT RTD values, repositioning rate and setup time were analyzed.Results: The absolute values of median (maximal) CBCT couch shifts were 0.4 (1.3) mm in VRT, 0.1 (2.5) mm in LNG, 0.2 (1.6) mm in LAT, 0.1(1.2) degree in YAW, 0.2 (1.4) degree in PITCH and 0.1(1.3) degree in ROLL. The couch shifts and AlignRT RTD values exhibited highly agreement except in VRT and PITCH (p value < 0.01), of which the differences were as small as negligible. We did not find any case of patient repositioning that was due to out-of-tolerance setup errors, i.e., 3 mm and 2 degree. The surface guided setup time ranged from 52 to 174 s, and the mean and median time was 97.72 s and 94 s respectively.Conclusions: The proposed surface guided SRT procedure with open-face mask immobilization is a step forward in improving patient comfort and positioning accuracy in the same process. Minimized initial setup errors and repositioning rate had been achieved with reasonably efficiency for routine clinical practice. [ABSTRACT FROM AUTHOR]

Introduction: Over half of women with surgically managed breast cancer in the UK undergo breast-conserving treatment (BCT). While photographs are shown prior to reconstructive surgery or complex oncoplastic procedures, standard practice prior to breast conservation is to simply describe the likely aesthetic changes. Patients have expressed the desire for more personalized information about likely appearance after surgery. The hypothesis was that viewing a three-dimensional (3D) simulation improves patients' confidence in knowing their likely aesthetic outcome after surgery. Methods: A randomized, controlled trial of 117 women planning unilateral BCT was undertaken. The randomization was three-way: standard of care (verbal description alone, control group), viewing two-dimensional (2D) photographs, or viewing a 3D simulation before surgery. The primary endpoint was the comparison between groups' median answer on a visual analogue scale (VAS) for the question administered before surgery: 'How confident are you that you know how your breasts are likely to look after treatment?'. Results: The median VAS in the control group was 5.2 (i.q.r. 2.6-7.8); 8.0 (i.q.r. 5.7-8.7) for 2D photography, and 8.9 (i.q.r. 8.2-9.5) for 3D simulation. There was a significant difference between groups (P<0.010) with post-hoc pairwise comparisons demonstrating a statistically significant difference between 3D simulation and both standard care and viewing 2D photographs (P<0.010 and P=0.012, respectively). Conclusion: This RCT has demonstrated that women who viewed an individualized 3D simulation of likely aesthetic outcome for BCT were more confident going into surgery than those who received standard care or who were shown 2D photographs of other women. The impact on longer-term satisfaction with outcome remains to be determined. Registration number: NCT03250260 (http://www.clinicaltrials.gov). [ABSTRACT FROM AUTHOR]

• Silver nanoparticles electrodeposited on fingermarked metallic surfaces. • Latent fingermarks aged up to one year visualized using silver nanoparticles. • SEM images reveal substrate dependent silver nanoparticle morphology. • Application to metallic objects of practical forensic value demonstrated. • Quantitative measure of fingermark image contrast developed. Fingerprints are central to criminal investigations as the most common physical evidence for identification of an individual. However, visualising latent (non-visible) fingerprints is a challenge, particularly on metallic surfaces. In this work, silver nanoparticles (AgNPs) were electrodeposited on fingermarked metal surfaces (stainless steel, copper, brass) by reduction of silver ions in aqueous AgNO 3 /KNO 3 under potentiostatic control. The effectiveness of this methodology and the quality of the developed fingermark images were assessed by scanning electron microscopy, the UK Home Office grading system, automated forensic analysis software and a novel quantitative contrast evaluation methodology. The images clearly permit identification of the ridge patterns and minutiae of the fingermark, even for aged samples and metallic substrates with complex background colour and/or texture, typified by keys and coins. On the basis of the data presented, we propose that this methodology is useful for latent fingermark development on diverse metals, producing high fidelity images of quantifiable contrast. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: We investigate the feasibility of surface guided radiation therapy (SGRT) for accelerated partial breast irradiation (APBI) by comparing it with in‐room, fan beam kV computed tomography on rails (CTOR) imaging of the targeted region. The uniqueness of our study is that all patients have multiple daily CTOR scans to compare corresponding SGRT AlignRT (VisionRT, United Kingdom) images to. Methods/materials: Twelve patients receiving APBI were enrolled in this study. Before each treatment fraction, after patients were setup on tattoos, SGRT was performed using AlignRT, and then target matching was performance using CTOR. The average and maximum difference in shifts between SGRT and CTOR were calculated and analyzed for each patient, so as the correlation between surgical cavity size and shift difference. Results: Our study showed that SGRT agreed well with CTOR for patients with small surgical cavity volume changes (<10%). There were nine patients who had a ≥5 mm maximum shift difference between SGRT and CTOR along any direction, and in two patients the difference was more than 10 mm (one patient with surgical cavity change 44.3% and one patient with 27 cc cavity volume decrease). All patients, except one, had a mean shift difference < 5 mm along any direction. Conclusion: For the patients studied here, SGRT appears to be a reasonable and potentially valuable image guidance approach for APBI for patients who experience small changes in surgical cavity volume (<10%) between CT simulation and treatment. However, there is potential for larger alignment errors (up to 11 mm) when using SGRT for patients who experience larger surgical cavity changes. [ABSTRACT FROM AUTHOR]

Aim The management of large non-pedunculated colorectal polyps ( LNPCPs) is complex, with widespread variation in management and outcome, even amongst experienced clinicians. Variations in the assessment and decision-making processes are likely to be a major factor in this variability. The creation of a standardized minimum dataset to aid decision-making may therefore result in improved clinical management. Method An official working group of 13 multidisciplinary specialists was appointed by the Association of Coloproctology of Great Britain and Ireland ( ACPGBI) and the British Society of Gastroenterology ( BSG) to develop a minimum dataset on LNPCPs. The literature review used to structure the ACPGBI/ BSG guidelines for the management of LNPCPs was used by a steering subcommittee to identify various parameters pertaining to the decision-making processes in the assessment and management of LNPCPs. A modified Delphi consensus process was then used for voting on proposed parameters over multiple voting rounds with at least 80% agreement defined as consensus. The minimum dataset was used in a pilot process to ensure rigidity and usability. Results A 23-parameter minimum dataset with parameters relating to patient and lesion factors, including six parameters relating to image retrieval, was formulated over four rounds of voting with two pilot processes to test rigidity and usability. Conclusion This paper describes the development of the first reported evidence-based and expert consensus minimum dataset for the management of LNPCPs. It is anticipated that this dataset will allow comprehensive and standardized lesion assessment to improve decision-making in the assessment and management of LNPCPs. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the reproducibility of three nonverbal facial expressions using a three-dimensional motion capture system. Design: Prospective, cross-sectional, controlled study. Setting: Glasgow Dental Hospital and School, University of Glasgow, United Kingdom. Patients and Participants: Thirty-two subjects, 16 males and 16 females. Methods: With a three-dimensional video passive stereophotogrammetry imaging system, maximal smile, cheek puff, and lip purse were captured for each subject. Anatomical facial landmarks were digitized on the first frame and then tracked automatically. The same facial expressions were captured 15 minutes later. Main Outcome Measures: The magnitude of each expression and speed of landmark displacement were calculated. The landmark motion curves were spatially and temporally aligned to calculate the similarity of the dynamic movements of the same landmarks between the captures. Results: There were no significant differences between individuals for magnitude (P = .892) or for speed (P = .456). There were significant differences in landmark movement similarity (P = .011); similarity was more reproducible for maximal smile. There was no significant gender effect on the difference in magnitude. There was a significant gender effect on speed to reach maximal smile (P= .044) and a pursed-lip expression (P = .038). There was a significant gender effect on landmark movement similarities (P = .031) for cheek puff expression. Conclusions: There were no differences in magnitude and speed for maximal smile, cheek puff, and lip purse between the two captures for all participants. For individual expressions, maximal smile expression had the highest similarity value for individual landmarks. [ABSTRACT FROM AUTHOR]

The dependency of soil particle wettability on soil water content implies that soils subjected to drying-wetting cycles become wettable with wetting and water repellent with drying. While this has been demonstrated widely, the results are contradictory when water repellent soils are subjected to a sequence of cycles. Added to this, past wettability measurements were seldom done in batches of samples collected from the field at natural or dry water contents, with little appreciation that slight particle size variations, different drying-wetting histories and fabric (as required by different wettability measurement methods) may alter the results. This note presents soil particle wettability-soil water content relations by means of an index test following staged drying and wetting paths over a period of 8 months for an untreated, oil-contaminated anthropogenic soil (a mixture of slag, coal particles, fly ash and mineral particles) from Barry Docks (UK), a site formally used for oil storage, which is to be remediated and redeveloped for housing. The results revealed a decrease in the water repellency and increasing mineralization and bacterial activity with the wetting and drying cycles. [ABSTRACT FROM AUTHOR]

President's foreword. For the Royal Statistical Society, the year 2010 was first and foremost the year of the 'getstats' campaign. The first World Statistics Day, sponsored by the United Nations, took place on 20.10.2010, and statistical Societies around the world took part in activities to raise awareness of our discipline and to celebrate its many achievements. According to the United Nations, the day 'was celebrated in over 130 countries and areas', and the Society chose this auspicious date to launch getstats, its 10-year statistical literacy campaign (). Statistical literacy is a key ability in today's data-driven society, comprising a fundamental set of skills and knowledge needed to make important life choices as well as to support roles in employment, research and policy making. At the launch event John Pullinger, Chair of the getstats steering group, argued that 'just as the 3 ''Rs'' were the new skills that were needed for advancement in the time of the industrial revolution, so the fourth ''R'' (statistical Reasoning) is now a vital life skill'. The campaign launch was marked by a paper read to the Society entitled 'Towards more accessible conceptions of statistical inference' by Chris Wild, Maxine Pfannkuch, Matt Regan (University of Auckland, New Zealand) and Nicholas Horton (Smith College, USA). This was followed by a reception at which excerpts of the BBC-commissioned film 'The joy of statistics' were shown (its YouTube clip has now topped 4 million views). There were also impressive demonstrations by developers of new exploratory data sites and data visualization tools, before a countdown to 8.10 p.m. (20.10) when the red button was pressed to launch the campaign. A further week of launch events followed in London and Plymouth organized by the RSS Centre for Statistical Education and included activities for teachers in schools and higher education, employers and young statisticians. Collaborating bodies for getstats include the Actuarial Profession, the British Academy, the Institute of Physics, the Nuffield Foundation, the Office for National Statistics (ONS), the Royal Academy of Engineering, the Royal Society, the UK Statistics Authority and many others. In particular, funding from the Nuffield Foundation is enabling the Society to appoint a Getstats Director in 2011, giving a real impetus to the campaign. The Society has more than 7000 members, of whom roughly 20% now have Chartered membership. The numbers of both Chartered Statisticians and Graduate Statisticians are growing, and roughly a seventh of professional members now have Chartered Scientist status. A new development this year is the provision of on-line continuing professional development recording; this facility is available to all Fellows of the Society. The continuing difficult economic climate has inevitably had an effect on the Society's finances, but the staff at Errol Street have been very effective in reducing expenses wherever possible and the Society has been able further to raise its profile and activities across a range of areas. As usual, the Society has run a very extensive programme of Ordinary Meetings, and Section and Local Group meetings, and it held a successful and enjoyable annual conference in Brighton. Highlights of the conference included well-received plenary lectures by Tim Davis, Peter Donnelly, Robert Groves, Nancy Reid and Robert Stine, a fish-and-chip supper on a wind-swept pier and a conference dinner with a highly entertaining after-dinner talk from Andrew Dilnot. The next (revamped) annual conference will take place in 2012, following a full review of the conference structure and consultation with the membership. The annual awards ceremony is another regular event in the Society's calendar. In 2010, as well as Guy, Greenfield and Chambers Medals, awards were given for Statistical Excellence in Journalism, which has continued to attract increased interest, and, for the first time this year, for Excellence in Official Statistics sponsored by the ONS. Plans are now in hand for an award for Excellence in Pharmaceutical Statistics sponsored jointly with PSI (Statisticians in the Pharmaceutical Industry). Short courses and workshops took place before the Brighton conference, and the Professional Development Centre ran a varied programme of nine training courses appealing both to statisticians and to statistics users throughout the year. The successful programme of workshops for journalists continued and, in addition, funding was obtained from the Department of Business, Innovation and Skills to co-ordinate science training for non-specialist journalists, with a member of staff seconded from the Parliamentary Office of Science and Technology acting as national co-ordinator. Through the Professional Affairs Committee, the Society continues to accredit universities for their statistics degrees both in the UK and overseas, and attracted an increasing number of candidates for its Ordinary and Higher Certificates and Graduate Diploma. Education in schools is also an essential part of the Society's activities, in which the Education Theme and the RSS Centre for Statistical Education are playing a vital role through the 'Significance in schools' projects, CensusAtSchool (funded by the ONS) and involvement in student conferences such as 'Planet Earth-over the limit?'. The Society actively continued its programme of policy development and communication, engaging with politicians and government, the media, education funding and regulatory bodies, and many other groups. For example, its call to the UK Statistics Authority for a comprehensive review of inflation measures was given wide media coverage and, before the general election, more than 300 Fellows and guests heard representatives of the three major political parties setting out their views on the official statistics system. The Statistics User Forum brings together users of official statistics across the spectrum from industry and local government, through to Learned Societies and research institutes. The Society's expertise is sought on a wide variety of subjects, and it submitted responses to consultations and invitations to comment from many official bodies including the Cabinet Office, the Forensic Science Regulator, the Law Commission, the ONS, the Office of Qualifications and Examinations Regulation and the UK Statistics Authority. In addition, it has regular meetings with the National Statistician, and with the other mathematical Learned Societies through its membership of the Council for the Mathematical Sciences. As part of the latter, there are regular meetings with the Chief Executives of the Higher Education Funding Council for England and of the Engineering and Physical Sciences Research Council. The shortage of trained manpower in statistics is an on-going problem, so it was particularly pleasing that a presentation by the Society at a liaison meeting with the manager of the Engineering and Physical Sciences Research Council's mathematics programme led to continued funding being earmarked for Masters training in statistics and operational research for a further 3 years. The Society's journal series (A, B and C) form a crucial part of the output of the Society, providing a service and resource not only to members but also to statisticians world wide. This year, more papers were submitted than ever before. Changes to the procedures for handling those papers submitted for possible reading to the Society were introduced: an important aspect is that all Sections of the Society are now encouraged to sponsor papers for reading. The year 2010 also saw a transformational step for Significance, with the agreement with the American Statistical Association for joint publication. This has resulted in a fourfold increase in the readership and plans for more frequent issues. To the relief of some, English spellings have been maintained, and the content included censuses, oil spills, ethnic profiling and Pictish carvings. The year also saw the launch of its own Web site, where rapidly changing short articles and news stories can be found. The Significance Web site was quickly accepted by the Google News aggregator, not only recognizing it as a reputable news source but also giving it greater prominence on Google. Links with other statistical Societies are increasingly important also. Discussions on closer co-operation took place in Paris with the Presidents of other European Societies, and these will be continued at the next International Statistical Institute World Congress in Dublin. This foreword gives only a taste of the activities of the Society in 2010. More details, with accounts of all the Themes, Section meetings and other activities, which give a much fuller picture of all that the Society does, can be found in the following report. A striking feature is the incredible number of names that appear in these pages. A very great many people give their services to the Society, as committee members, organizers and speakers, as editors and referees, and in other capacities. They contribute enormous energy, enthusiasm and commitment, complementing that of the Society's permanent staff. The Society owes all these people, staff and volunteers alike, a great debt of gratitude for all they enable it to achieve. Valerie Isham [ABSTRACT FROM AUTHOR]

In June 2009 a community workshop discussed what priorities in landing-site selection would drive UK involvement in Mars lander missions. The organizers and participants (below) summarize the conclusions of the workshop and their overview of current and future priorities in the UK search for signs of life on Mars. [ABSTRACT FROM AUTHOR]

Surface texture is generally accepted as a key sensory factor of food materials and has great impact on consumers' perception and expectation of a food product. However, no authentic definition has been given in the literature for the term surface texture. Its real meaning is often rather confusing, varying from case to case and from person to person. A general consensus is that surface texture is a multi-parameter sensory factor composed of those surface-related features which can be perceived by visual, tactile handfeel, and tactile mouthfeel senses. A list of such surface-related features has been produced in this review, and of those, topographical properties are probably the most intensively investigated features in literature and are discussed in detail in this paper. The surface texture of a food can be characterized by either sensory panel tests or by physical instrument tests. The former uses panellists (trained or untrained) for sensory assessment, while the latter applies physical techniques to characterize the surface. While sensory tests are widely used for studies on consumers' perception and preference of foods, instrumental characterization uses one or few parameters to define a surface (either qualitatively or quantitatively). Physical techniques used for surface characterization are categorized into two groups: surface contacting and non-surface contacting. The former include tribometer, surface force apparatus, contact profilometry, atomic force microscopy, friction force microscopy, etc. Non-surface contacting techniques include gloss metre, fiber optic reflectometer, angle-resolved light scattering apparatus, surface glistening points method, electron microscopy, confocal laser scanning microscopy, etc. The principles and application examples of these techniques were discussed in this review. [ABSTRACT FROM AUTHOR]