Optimum projection angle for attaining maximum distance in a soccer punt kick

Copyright @ Journal of Sports Science and Medicine 2011.This article has been made available through the Brunel Open Access Publishing Fund.To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10 degrees and 90 degrees. The kicks were recorded by a video camera at 100 Hz and a 2-D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player's optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player's preferred projection angles (40 degrees and 44 degrees). In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45 degrees. In the punt kicks studied here, the optimum projection angle was close to 45 degrees because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45 degrees.This article is made available through the Brunel University Open Access Publishing Fund

First-principles calculation of the elastic dipole tensor of a point defect: Application to hydrogen in α-zirconium

The elastic dipole tensor is a fundamental quantity relating the elastic field and atomic structure of a point defect. We review three methods in the literature to calculate the dipole tensor and apply them to hydrogen in α -zirconium using density functional theory (DFT). The results are compared with the dipole tensor deduced from earlier experimental measurements of the λ tensor for hydrogen in α -zirconium. There are significant errors with all three methods. We show that calculation of the λ tensor, in combination with experimentally measured elastic constants and lattice parameters, yields dipole tensor components that differ from experimental values by only 10%–20%. There is evidence to suggest that current state-of-the-art DFT calculations underestimate bonding between hydrogen and α -zirconium

Scanning the visual world: a study of patients with homonymous hemianopia.

Published versio

The association between sleep patterns and obesity in older adults.

BackgroundReduced sleep duration has been increasingly reported to predict obesity. However, timing and regularity of sleep may also be important. In this study, the cross-sectional association between objectively measured sleep patterns and obesity was assessed in two large cohorts of older individuals.MethodsWrist actigraphy was performed in 3053 men (mean age: 76.4 years) participating in the Osteoporotic Fractures in Men Study and 2985 women (mean age: 83.5 years) participating in the Study of Osteoporotic Fractures. Timing and regularity of sleep patterns were assessed across nights, as well as daytime napping.ResultsGreater night-to-night variability in sleep duration and daytime napping were associated with obesity independent of mean nocturnal sleep duration in both men and women. Each 1 h increase in the standard deviation of nocturnal sleep duration increased the odds of obesity 1.63-fold (95% confidence interval: 1.31-2.02) among men and 1.22-fold (95% confidence interval: 1.01-1.47) among women. Each 1 h increase in napping increased the odds of obesity 1.23-fold (95% confidence interval: 1.12-1.37) in men and 1.29-fold (95% confidence interval: 1.17-1.41) in women. In contrast, associations between later sleep timing and night-to-night variability in sleep timing with obesity were less consistent.ConclusionsIn both older men and women, variability in nightly sleep duration and daytime napping were associated with obesity, independent of mean sleep duration. These findings suggest that characteristics of sleep beyond mean sleep duration may have a role in weight homeostasis, highlighting the complex relationship between sleep and metabolism

A YOLOv5-based network for the detection of a diffuse reflectance spectroscopy probe to aid surgical guidance in gastrointestinal cancer surgery

PURPOSE: A positive circumferential resection margin (CRM) for oesophageal and gastric carcinoma is associated with local recurrence and poorer long-term survival. Diffuse reflectance spectroscopy (DRS) is a non-invasive technology able to distinguish tissue type based on spectral data. The aim of this study was to develop a deep learning-based method for DRS probe detection and tracking to aid classification of tumour and non-tumour gastrointestinal (GI) tissue in real time. METHODS: Data collected from both ex vivo human tissue specimen and sold tissue phantoms were used for the training and retrospective validation of the developed neural network framework. Specifically, a neural network based on the You Only Look Once (YOLO) v5 network was developed to accurately detect and track the tip of the DRS probe on video data acquired during an ex vivo clinical study. RESULTS: Different metrics were used to analyse the performance of the proposed probe detection and tracking framework, such as precision, recall, mAP 0.5, and Euclidean distance. Overall, the developed framework achieved a 93% precision at 23 FPS for probe detection, while the average Euclidean distance error was 4.90 pixels. CONCLUSION: The use of a deep learning approach for markerless DRS probe detection and tracking system could pave the way for real-time classification of GI tissue to aid margin assessment in cancer resection surgery and has potential to be applied in routine surgical practice

Inflammatory thresholds and the species-specific effects of colonising bacteria in stable chronic obstructive pulmonary disease

There has been increasing interest in the use of newer, culture-independent techniques to study the airway microbiome of COPD patients. We investigated the relationships between the three common potentially pathogenic microorganisms (PPMs) Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, as detected by quantitative PCR (qPCR), and inflammation and health status in stable patients in the London COPD cohort

Variations in Treatment Delivery for Patients with Neovascular AMD in the UK: Results from an Ophthalmology Trainee Clinical Research Network Study

INTRODUCTION: The aim of this study was to determine treatment delivery patterns for patients with neovascular age-related macular degeneration (nAMD) across the UK through an ophthalmology trainee research network delivered observational study. METHODS: Data were collected via an online tool by potential research collaborators identified by the Ophthalmology Trainee Clinical Trial Network (OCTN). Collaborators were asked to comment on periprocedural practices of treatment of nAMD in their eye unit including treatment location and injectors, clinical assessment and routine observation in patients undergoing intravitreal treatment. RESULTS: Data were available from 26 units around the United Kingdom. Survey methodology refinement was approximately 3 months, and the average response time was 4.9 ± 2.4 days. The majority of responders confirmed that treatment was undertaken as a "one-stop" service (n = 15, 58%), delivered in a clean room (n = 23, 88%). In the majority of units, doctors administered injections (n = 24, 92%), but significant treatment was also given by nurse injectors (n = 21, 81%). All collaborators reported that patients underwent visual acuity testing and optical coherence tomography imaging at all visits, but other imaging including fundus fluorescein angiography (FFA) did not take place in all cases (n = 17, 65%) and only at baseline visit. CONCLUSIONS: These results demonstrate the feasibility of conducting ophthalmology trainee led and delivered observational studies. Our results show that FFA is not routinely used in the diagnosis of nAMD in the units sampled; most injections are carried out in a clean room, and ophthalmic nurses delivering injections is a highly prevalent model of care in the UK

Pharmacokinetics, Pharmacodynamics, and Safety of Lisinopril in Pediatric Kidney Transplant Patients: Implications for Starting Dose Selection

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111964/1/cpt127.pd