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Introduction: Dissolved-phase 129 Xe MRI metrics suggest that gas diffusion may be more compromised at submaximal lung inflation compared to maximal inflation. We hypothesized that this diffusion deficit could be detected by comparing the carbon monoxide transfer coefficient (Kco) at submaximal lung inflation to that measured routinely at total lung capacity (TLC)., Methods: Asthma and COPD patients performed carbon monoxide diffusion tests, first at maximal lung inflation for routine Kco and alveolar volume VA and then, at a 30 % reduced inflation (redux; obtaining Kco redux and VA redux ). At both inflations mixing efficiency was determined as VA/TLC and VA redux /TLC redux to examine a potential effect on Kco redux /Kco behavior., Results: In normal subjects (n=36), median Kco redux /Kco amounted to 130 [IQR:122-136]% as expected for normal Kco recruitment response. However, 60 % of asthma patients (49/83) and 80 % of COPD patients (44/55) showed reduced Kco recruitment at submaximal inflation (Kco redux /Kco<122 %). In the asthma group, with otherwise normal routine Kco, Kco redux /Kco was significantly correlated with RV/TLC ratio (r=-0.53;P<0.001), but not with VA/TLC. In COPD patients, all with abnormal routine Kco, abnormal Kco redux /Kco response occurred in those patients with lower FEV 1 , higher RV/TLC and lower VA/TLC (P<0.01 for all)., Conclusion: Sizeable portions of COPD and asthma patients showed a lack of normal Kco recruitment at submaximal lung inflation, related to high RV/TLC. In asthma, this was the case despite normal Kco at full lung inflation, suggesting that hyperinflation at lung volumes less than TLC affects the carbon monoxide diffusion rate constant by distorting pulmonary capillaries and alveolar-capillary membranes., Competing Interests: Declaration of Competing Interest None., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: Non-contrast CT head scans provide rapid and accurate diagnosis of acute head injury; however, increased utilisation of CT head scans makes it difficult to prioritise acutely unwell patients and places pressure on busy emergency departments (EDs). This study validates an AI algorithm to triage patients presenting with Intracranial Haemorrhage (ICH) or Acute Infarct whilst also identifying a subset of patients as Normal, with the potential to function as a rule-out test., Methods: In total, 390 CT head scans were collected from 3 institutions in the UK, US and India. Ground-truth labels were assigned by 3 FRCR consultant radiologists. AI performance, as well as the performance of 3 independent radiologists, was measured against ground-truth labels., Results: The algorithm showed AUC values of 0.988 (0.978-0.994), 0.933 (0.901-0.961) and 0.939 (0.919-0.958) for ICH, Acute Infarct and Normal, respectively. Sensitivity/specificity for ICH and Acute Infarct were 0.988/0.925 and 0.833/0.927, respectively, compared to 0.907/0.991 and 0.618/0.977 for radiologists. AI rule-out of Normal scans achieved 0.93% negative predictive value (NPV) for the removal of 54.3% of Normal cases, compared to 86.8% NPV for radiologists., Conclusion: We show our algorithm can provide effective triage of ICH and Acute Infarct to prioritise acutely unwell patients. AI can also benefit clinical accuracy, with the algorithm identifying 91.3% of radiologist false negatives for ICH and 69.1% for Acute Infarct. Rule-out of Normal scans has huge potential for workload management in busy EDs, in this case removing 27.4% of all scans with no acute findings missed., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The physical demands and rally characteristics of elite-standard men's squash have not been well documented since recent rule changes (scoring and tin height). This information is needed to design optimal training drills for physical conditioning provided here based on an analysis of movement and shot information. Matches at the 2010 (n = 14) and 2011 (n = 27) Rowe British Grand Prix were analysed. Rallies were split into four ball-in-play duration categories using the 25th (short), 75th (medium), 95th percentiles (long) and maximum values. Cohen's d and chi-squared tests of independence evaluated effects of rally and rule changes on patterns of play. The proportion of long, middle and short shots was related to the duration of the rally with more shots played in the middle and front of the court in short rallies (phi = 0.12). The frequencies of shots played from different areas of the court have not changed after the adoption of new rules but there is less time available to return shots that reflect the attacking nature of match play for elite-standard men players. Aspiring and current elite-standard players need to condition themselves to improve their ability to cope with these demands using the ghosting patterns presented that mimic demands of modern match play.

Tactics in squash have typically been assessed using the frequency of different shot types played at different locations on the court either without reference to other relevant information or on the basis of the preceding shot. This paper presents a new squash specific method for categorizing court locations in which the ball was played, a novel techniques for assessing the reliability of this method and presents typical shots responses in these new areas controlled for preceding shot as well as the time between shots and the handedness of the players. Twelve games were viewed using the SAGIT/Squash software and 2907 shots viewed a second time from a video image taken from behind the court with an overall agreement of 88.90% for the court location data and 99.52% for shot type. 3192 shots from 9 matches from the 2003 World Team Championships were analyzed in SAGIT/Squash. In the court areas analyzed between 2 and 7 shot responses were predominant suggesting tactical patterns were evident. This was supported by differences evident between shot responses played from the two back corners where the backhand side was characterized by a predominance of straight drives whereas straight and crosscourt drives were played on the forehand side. These results tended to confirm that tactics i.e., consistent shot types, are played although these are only apparent when factors that determine shot selection are accounted for. This paper has controlled for some of these factors but others need to be considered e.g., if individual player profiles are to be ascertained., (Copyright © 2014 Elsevier B.V. All rights reserved.)

No previous research in squash has considered the time between shots or the proximity of the ball to a wall, which are two important variables that influence shot outcomes. The aim of this paper was to analyse shot types to determine the extent to which they are played in different court areas and a more detailed analysis to determine whether the time available had an influence on the shot selected. Ten elite matches, contested by fifteen of the world's top right handed squash players (age 27 ± 3.2, height 1.81 ± 0.06 m, weight 76.3 ± 3.7 kg), at the men's World Team Championships were processed using the SAGIT/Squash tracking system with shot information manually added to the system. Results suggested that shot responses were dependent upon court location and the time between shots. When these factors were considered repeatable performance existed to the extent that one of two shots was typically played when there was limited time to play the shot (< 1.20s). For example, it was clear that when players did not have a lot of time to hit the ball (low time i.e. < 1.06s, and mid time i.e. 1.06 - 1.20s) in the front left corner close to the side wall, the crosscourt lob was used frequently (44.30% and 36.31% respectively) whereas when there was more time this shot was seldom used (13.64%). Consequently variant and invariant behaviour were shown to exist in elite squash although for the first time it was suggested that the availability of time to play a shot contributed to which of these behaviours was evident. This analysis could be extended by adopting a case study approach to see how individual differences in strategy and tactics affect shot selections. Key pointsPrevious research has suggested that a playing strategy, elements decided in advance of the match, may be evident for elite players by examining court location and preceding shot type, however these parameters alone are unlikely to be sufficient predictors.At present there is no known analysis in squash, or indeed in any of the racket sports, that has quantified the time available to respond to different shot types. An understanding of the time interval between shots and the movement characteristics of the player responding to different shots according to the court positions might facilitate a better understanding of the dynamics that determine shot selection.Some elements of a general playing strategy were evident e.g. predominately hitting to the back left of the court, but tactical differences in shot selection were also evident on the basis of court location and time available to play a shot.

Background and Objective: Q-switched laser therapy is commonly used for the removal of tattoos. However, despite ever increasing demand for this intervention, a better understanding of the mechanisms that result in pigment reduction is required in order to optimise outcomes and reduce the number of treatment episodes., Study Design: A finite element analysis computer simulation was developed to model the fragmentation response of ink granules during irradiation of a professional black tattoo using a Q-switched Nd:YAG laser. Thermal and acoustic mechanisms were considered, allowing the optimal laser settings to be predicted throughout the course of treatment. Changes in the thermal properties of the ink during heating were taken into account to improve the reliability of the results obtained., Results: The simulated results are in close agreement with clinical observations. Thermal fragmentation was shown to be the dominant mechanism in pigment reduction when using a 6 nanoseconds pulse at 1,064 nm. In order to provide maximum clearance whilst maintaining acceptable levels of tissue thermal damage, later treatments were shown to benefit from higher fluence levels than initial treatments. Larger spot diameters were also preferable throughout the course of treatment., Conclusions: The results from the simulation build upon previous work carried out in the field, applying ink thermal coefficients which vary with temperature for the first time. These results compliment clinical knowledge, suggesting that a proactive increase in fluence during a course of treatments is likely to improve the response to laser therapy., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: This paper describes and analyses Rwanda's science-based health product 'innovation system', highlighting examples of indigenous innovation and good practice. We use an innovation systems framework, which takes into account the wide variety of stakeholders and knowledge flows contributing to the innovation process. The study takes into account the destruction of the country's scientific infrastructure and human capital that occurred during the 1994 genocide, and describes government policy, research institutes and universities, the private sector, and NGOs that are involved in health product innovation in Rwanda., Methods: Case study research methodology was used. Data were collected through reviews of academic literature and policy documents and through open-ended, face-to-face interviews with 38 people from across the science-based health innovation system. Data was collected over two visits to Rwanda between November - December 2007 and in May 2008. A workshop was held in Kigali on May 23rd and May 24th 2009 to validate the findings. A business plan was then developed to operationalize the findings., Results and Discussion: The results of the study show that Rwanda has strong government will to support health innovation both through its political leadership and through government policy documents. However, it has a very weak scientific base as most of its scientific infrastructure as well as human capital were destroyed during the 1994 genocide. The regulatory agency is weak and its nascent private sector is ill-equipped to drive health innovation. In addition, there are no linkages between the various actors in the country's health innovation system i.e between research institutions, universities, the private sector, and government bureaucrats., Conclusions: Despite the fact that the 1994 genocide destroyed most of the scientific infrastructure and human capital, the country has made remarkable progress towards developing its health innovation system, mainly due to political goodwill. The areas of greatest potential for Rwanda are in traditional plant technologies. However, there is need for investments in domestic skill development as well as infrastructure that will enhance innovation. Of foremost importance is the establishment of a platform to link the various actors in the health innovation system.

The importance of dominating the T in squash is recognized by coaches and players but there has been little formal investigation of this aspect of tactical play. Consequently, the aim of this research was to analyse player occupancy of a T area, to establish whether there are differences between winners and losers of games at different playing standards. An automated player-tracking system, with operator supervision and intervention, captured players' movements during matches at the World Team Championships (n = 11), the Slovenian National Championships (n = 11), and a local tournament (n = 15). Frequency of occupying the T area at the moment opponents played their shot best discriminated playing standard. Winners spent a greater proportion of total playing time in the T area than losers (P < 0.001), except during closely contested games. The results suggest that time in the T area indicates dominance of rallies. Future studies need to consider both between-group (playing standard) and within-game (individual player standard) differences, as both were shown to influence the time players spent in the T area.

Unlabelled: Alcopops, which are fruit flavoured alcoholic drinks, have been implicated as an aetiological factor in dental erosion. They are commonly drunk by 18-25 year-olds owing to their fruity flavours, but increasingly in the UK they are consumed by underage teenagers. A popular lemon-based vodka alcopop is presented as a possible causative factor of dental erosion in a 19-year-old female, who started drinking it regularly at the age of 15 for four years. She was subsequently treated preventively and conservatively in a National Health Service (NHS) dental practice, in North Wales, using freehand compomer and minimally prepared porcelain veneers., Clinical Relevance: Frequent consumption of excessive amounts of extrinsic acids causes significant dental erosion. Alcopops, owing to their high citrus fruit contents and acidic pH, are known to cause erosion. They are commonly drunk by adults up to their mid twenties, but increasingly so by underage teenagers, especially females.

In this historical review covering the past 25 years, we reflect on the content of manuscripts relevant to the Sport Performance section of the Journal of Sports Sciences. Due to the wide diversity of sport performance research, the remit of the Sport Performance section has been broad and includes mathematical and statistical evaluation of competitive sports performances, match- and notation-analysis, talent identification, training and selection or team organization. In addition, due to the academic interests of its section editors, they adopted a quality-assurance role for the Sport Performance section, invariably communicated through key editorials that subsequently shaped the editorial policy of the Journal. Key high-impact manuscripts are discussed, providing readers with some insight into what might lead an article to become a citation "classic". Finally, landmark articles in the areas of "science and football" and "notation analysis" are highlighted, providing further insight into how such articles have contributed to the development of sport performance research in general and the Journal of Sports Sciences in particular.

A 21-year-old Caucasian male presented to an oral medicine clinic with bilateral nuchal to frontal headache that was associated with burning eyes and lacrimation. Following a string of previous consultations with a variety of specialists, no diagnosis had been made. Treatment was carried out empirically, with the best improvement experienced when the patient was put on a combination of gabapentin and dothiepin treatment. This case highlights the importance of multidisciplinary management of headaches, as well as constant revision of the International Classification of Headache Disorders.

A three-tiered, hierarchical, risk-based prioritisation system was developed to assess the number of standing waters in Great Britain (GB) at risk from eutrophication. The scheme is based on four properties: importance, hazard, sensitivity to enrichment and sensitivity to recovery. Lake size, conservation status and legislative requirements were used to assess importance. The anthropogenic total phosphorus (P) load estimated from land cover, livestock and population data was used as a measure of the eutrophication hazard. Lakes with a retention time >3 days were considered to be sensitive to enrichment. The Wederburn depth (an estimate of the average summer thermocline depth) was used to predict the potential response of a lake to nutrient reduction. Lakes which were mainly stratified or fully stratified during the summer were expected to respond quickly to remediation. An initial Tier 1 risk assessment was made for all standing waters in GB (approximately 14,300 with surface area greater than 1 ha), using the four parameters derived from nationally available, GIS-based data sources held in the GB Lakes Inventory. Of the 2362 important lakes in GB, the system identified 1736 with low hazard but under potential threat because of their high sensitivity to enrichment. The system assessed that the ecology of 212 was likely to be damaged by eutrophication owing to high hazard and high sensitivity but with relatively poor chance of recovery following remediation. A further 332 lakes were considered to be damaged but were likely to respond to rehabilitation. In summary, the risk-based prioritisation system performed well and provides a useful tool for assessing standing waters at risk of eutrophication on a national basis. Inevitably, however, the need for nationally available datasets at Risk Tier 1 results in data resolution issues and errors may occur. The results highlight the importance of data validation using lake-specific information at Risk Tier 2.

Two methods to produce (2S)-5-amino-2-(1-n-propyl-1H-imidazol-4-ylmethyl)-pentanoic acid were investigated. Diastereoisomeric salt resolution, using the quinidine salt, gave the desired intermediate in 98% ee and 33% yield. Asymmetric hydrogenation of various substrates gave high conversions, with up to 83% ee. Integration of these two approaches via asymmetric hydrogenation of a quinidine salt substrate followed by crystallization provided the desired intermediate in 94% ee and 76% yield.

Early research into how goals were scored in association football (Reep and Benjamin, 1968) may have shaped the tactics of British football. Most coaches have been affected, to a greater or lesser extent, by the tactics referred to as the "long-ball game" or "direct play", which was a tactic employed as a consequence of this research. Data from these studies, published in the late 1960s, have been reconfirmed by analyses of different FIFA World Cup tournaments by several different research groups. In the present study, the number of passes that led to goals scored in two FIFA World Cup finals were analysed. The results conform to that of previous research, but when these data were normalized with respect to the frequency of the respective lengths of passing sequences, there were more goals scored from longer passing sequences than from shorter passing sequences. Teams produced significantly more shots per possession for these longer passing sequences, but the strike ratio of goals from shots is better for "direct play" than for "possession play". Finally, an analysis of the shooting data for successful and unsuccessful teams for different lengths of passing sequences in the 1990 FIFA World Cup finals indicated that, for successful teams, longer passing sequences produced more goals per possession than shorter passing sequences. For unsuccessful teams, neither tactic had a clear advantage. It was further concluded that the original work of Reep and Benjamin (1968), although a key landmark in football analysis, led only to a partial understanding of the phenomenon that was investigated.

Fifty-five paleolimnological records from lakes in the circumpolar Arctic reveal widespread species changes and ecological reorganizations in algae and invertebrate communities since approximately anno Domini 1850. The remoteness of these sites, coupled with the ecological characteristics of taxa involved, indicate that changes are primarily driven by climate warming through lengthening of the summer growing season and related limnological changes. The widespread distribution and similar character of these changes indicate that the opportunity to study arctic ecosystems unaffected by human influences may have disappeared.

Background: External snapping hip is an entity that describes a snap that is felt on the lateral aspect of the hip. Several surgical interventions are described., Hypothesis: The external snapping hip can be corrected with a simple procedure that is minimally invasive and less demanding than other techniques., Study Design: This is a retrospective review from June 1994 until January 2002 looking at released external snapping hips., Methods: There were 16 patients with 17 hips; follow-up was in 15 patients with 16 snapping hips. Twelve patients with 13 hips were contacted by telephone interview, and 3 were followed up by their most recent chart note. All underwent the same procedure performed by the senior author. The questionnaire was conducted at an average of 32.5 months after surgery (range, 9-74 months). For 3 patients, chart-only follow-up was at 6 weeks, 3 months, and 6 months, respectively., Results: Fourteen of 16 hips remained asymptomatic after final surgical release (2 hips needed a second release). All patients contacted by telephone would undergo the same procedure again if faced with the same symptoms., Conclusions: This technique is simpler than most of those previously described with the benefit of no formal postoperative regimen and comparable results.

Background: ERCP has become widely available for the diagnosis and treatment of benign and malignant pancreaticobiliary diseases. In this prospective study, the overall complication rate and risk factors for diagnostic and therapeutic ERCP were identified., Methods: Data were collected prospectively on patient characteristics and endoscopic techniques from 1223 ERCPs performed at a single referral center and entered into a database. Univariate and multivariate analyses were used to identify risk factors for ERCP-associated complications., Results: Of 1223 ERCPs performed, 554 (45.3%) were diagnostic and 667 (54.7%) therapeutic. The overall complication rate was 11.2%. Post-ERCP pancreatitis was the most common (7.2%) and in 93% of cases was self-limiting, requiring only conservative treatment. Bleeding occurred in 10 patients (0.8%) and was related to a therapeutic procedure in all cases. Nine patients had cholangitis develop, most cases being secondary to incomplete drainage. There was one perforation (0.08%). All other complications totaled 1.5%. Variables derived from cannulation technique associated with an increased risk for post-ERCP pancreatitis were precut access papillotomy (20%), multiple cannulation attempts (14.9%), sphincterotome use to achieve cannulation (13.1%), pancreatic duct manipulation (13%), multiple pancreatic injections (12.3%), guidewire use to achieve cannulation (10.2%), and the extent of pancreatic duct opacification (10%). Patient characteristics associated with an increased risk of pancreatitis were sphincter of Oddi dysfunction (21.7%) documented by manometry, previous ERCP-related pancreatitis (19%), and recurrent pancreatitis (16.2%). Pain during the procedure was an important indicator of an increased risk of post-ERCP pancreatitis (27%). Independent risk factors for post-ERCP pancreatitis were identified as a history of recurrent pancreatitis, previous ERCP-related pancreatitis, multiple cannulation attempts, pancreatic brush cytology, and pain during the procedure., Conclusions: The most frequent ERCP-related complication was pancreatitis, which was mild in the majority of patients. The frequency of post-ERCP pancreatitis was similar for both diagnostic and therapeutic procedures. Bleeding was rare and mostly associated with sphincterotomy. Other complications such as cholangitis and perforation were rare. Specific patient- and technique-related characteristics that can increase the risk of post-ERCP complications were identified.

This paper overviews the diverse information technologies that are used to provide athletes with relevant feedback. Examples taken from various sports are used to illustrate selected applications of technology-based feedback. Several feedback systems are discussed, including vision, audition and proprioception. Each technology described here is based on the assumption that feedback would eventually enhance skill acquisition and sport performance and, as such, its usefulness to athletes and coaches in training is critically evaluated.

In this paper, we identify appropriate statistical methods for analysing categorical differences in discrete variables or 'performance indicators' resulting from performance analysis. The random mechanisms associated with discrete events do not follow a normal distribution; that is, the normal distribution is a continuous not a discrete probability distribution. We propose appropriate statistical methods based on two key discrete probability distributions, the Poisson and binomial distributions. Two approaches are proposed and compared using examples from notational analysis. The first approach is based on the classic chi-square test of significance (both the goodness-of-fit test and the test of independence). The second approach adopts a more contemporary method based on log-linear and logit models fitted using the statistical software GLIM. Provided relatively simple one-way and two-way comparisons in categorical data are required, both of these approaches result in very similar conclusions. However, as soon as more complex models or higher-order comparisons are required, the approach based on log-linear and logit models is shown to be more effective. Indeed, when investigating those factors and categorical differences associated with binomial or binary response variables, such as the proportion of winners when attempting decisive shots in squash or the proportion of goals scored from all shots in association football, logit models become the only realistic method available. By applying log-linear and logit models to discrete events resulting from notational analysis, greater insight into the underlying mechanisms associated with sport performance can be achieved.

The existence of structure in sport competition is implicated in the widespread practice of using the information gathered from a past contest to prepare for a future contest. Based on this reasoning, we previously analysed squash match-play for evidence of signature traits from among the stochastic relations between the various types of shot. The mixed findings from these analyses led us to re-analyse squash match-play as a dynamical system. Here, we extend this line of investigation with some suggestions as to how various sports might be described further within this theoretical framework. We offer some examples of dynamical interactions in dyadic (i.e. one vs one) and team (e.g. many vs many) sports, as well as some predictions from a dynamical systems analysis for these types of sports contests. This paper should serve to initiate further research into the complex interactions that occur in sport competition.

The aims of this paper are to examine the application of performance indicators in different sports and, using the different structural definitions of games, to make general recommendations about the use and application of these indicators. Formal games are classified into three categories: net and wall games, invasion games, and striking and fielding games. The different types of sports are also sub-categorized by the rules of scoring and ending the respective matches. These classes are analysed further, to enable definition of useful performance indicators and to examine similarities and differences in the analysis of the different categories of game. The indices of performance are sub-categorized into general match indicators, tactical indicators, technical indicators and biomechanical indicators. Different research examples and the accuracy of their presentation are discussed. We conclude that, to enable a full and objective interpretation of the data from the analysis of a performance, comparisons of data are vital. In addition, any analysis of the distribution of actions across the playing surface should also be presented normalized, or non-dimensionalized, to the total distribution of actions across the area. Other normalizations of performance indicators should also be used more widely in conjunction with the accepted forms of data analysis. Finally, we recommend that biomechanists should pay more attention to games to enrich the analysis of performance in these sports.