An international group of experts convened to provide guidance for employers to promote the avoidance of prolonged periods of sedentary work. The set of recommendations was developed from the totality of the current evidence, including long-term epidemiological studies and interventional studies of getting workers to stand and/or move more frequently. The evidence was ranked in quality using the four levels of the American College of Sports Medicine. The derived guidance is as follows: for those occupations which are predominantly desk based, workers should aim to initially progress towards accumulating 2 h/day of standing and light activity (light walking) during working hours, eventually progressing to a total accumulation of 4 h/day (prorated to part-time hours). To achieve this, seated-based work should be regularly broken up with standing-based work, the use of sit–stand desks, or the taking of short active standing breaks. Along with other health promotion goals (improved nutrition, reducing alcohol, smoking and stress), companies should also promote among their staff that prolonged sitting, aggregated from work and in leisure time, may significantly and independently increase the risk of cardiometabolic diseases and premature mortality. It is appreciated that these recommendations should be interpreted in relation to the evidence from which they were derived, largely observational and retrospective studies, or short-term interventional studies showing acute cardiometabolic changes. While longer term intervention studies are required, the level of consistent evidence accumulated to date, and the public health context of rising chronic diseases, suggest initial guidelines are justified. We hope these guidelines stimulate future research, and that greater precision will be possible within future iterations.

To determine whether perching dragonflies visually assess the distance to potential prey items, we presented artificial prey, glass beads suspended from fine wires, to perching dragonflies in the field. We videotaped the responses of freely foraging dragonflies (Libellula luctuosa and Sympetrum vicinum-Odonata, suborder Anisoptera) to beads ranging from 0.5 mm to 8 mm in diameter, recording whether or not the dragonflies took off after the beads, and if so, at what distance. Our results indicated that dragonflies were highly selective for bead size. Furthermore, the smaller Sympetrum preferred beads of smaller size and the larger Libellula preferred larger beads. Each species rejected beads as large or larger than their heads, even when the beads subtended the same visual angles as the smaller, attractive beads. Since bead size cannot be determined without reference to distance, we conclude that dragonflies are able to estimate the distance to potential prey items. The range over which they estimate distance is about 1 m for the larger Libellula and 70 cm for the smaller Sympetrum. The mechanism of distance estimation is unknown, but it probably includes both stereopsis and the motion parallax produced by head movements.

To ascertain and clarify the effectiveness and advantages of the geometric staged excision technique for the removal of lentigo maligna (LM) and lentigo maligna melanoma (LMM).Design: This was a retrospective review of a patient database composed of 293 cases of LM and LMM.Setting: The Laser and Dermatologic Surgery Center in St Louis, Missouri, an academic-affiliated, private dermatologic surgery center.Patients: All patients with a diagnosis of LM and LMM treated by staged excision from 1999 to 2007. Main Outcome Measures:The overall rate of recrudescence, margins required for clearance, stages re-quired for clearance, and lesional characteristics were examined.Results: The rate of recrudescence after geometric staged excision was 1.7% (4/239), with a mean of 32.3 months of follow-up. The mean margin to clearance after excision was 6.6 mm for LM and 8.2 mm for LMM. A total of 11.7% of LMM was initially diagnosed as LM on biopsy, with the invasive component discovered during the excision.Conclusions: Geometric staged excision is an optimal method of removal of LM and LMM given its low rate of recrudescence and ability for complete examination of the peripheral and deep margins of the specimens.

Injury prevention should aim to protect the hands and wrists of elite amateur boxers.

Objective:The BRAIN Study was established to assess the associations between selfreported concussions and cognitive function among retired rugby players.Methods: Former elite-level male rugby union players (50+ years) in England were recruited. Exposure to rugby-related concussion was collected using the BRAIN-Q tool. The primary outcome measure was the Preclinical Alzheimer Cognitive Composite (PACC). Linear regressions were conducted for the association between concussion and PACC score, adjusting for confounders.Results: A total of 146 participants were recruited. The mean (standard deviation) length of playing career was 15.8 (5.4) years. A total of 79.5% reported rugby-relatedThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.