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International audience; Regular participation in intensive physical exercise is associated with several structural and electrophysiological cardiac adaptations that enhance diastolic filling and facilitate a sustained increase in the cardiac output that is fundamental to athletic excellence. Such cardiac adaptations are collectively referred to as the 'Athlete's Heart' and are frequently reflected on the 12-lead ECG and imaging studies. Thorough knowledge relating to exercise-associated cardiovascular adaptation is imperative for the purposes of differentiating physiological adaptation from cardiac pathology, since an erroneous diagnosis of cardiac disease has potentially serious consequences for the athlete's physical, psychological, social and financial well-being. The majority of studies investigating the cardiovascular adaptation to exercise are based on cohorts of Caucasian athletes. However, there is mounting evidence that ethnicity is an important determinant of the objective manifestations of cardiovascular adaptation to exercise. The most pronounced paradigm of ethnically distinct cardiovascular adaptation to exercise stems from athletes of African/Afro-Caribbean descent, who exhibit a significantly higher prevalence of repolarisation anomalies and left ventricular hypertrophy, compared to Caucasian athletes; the differentiation between athlete's heart and hypertrophic cardiomyopathy is particularly challenging in this ethnic group. The extrapolation of ECG and echocardiographic criteria used to diagnose potentially serious cardiac disorders in Caucasian athletes to the African/Afro-Caribbean athlete population would result in an unacceptable number of unnecessary investigations and increased risk of false disqualification from competitive sport. Accurate interpretation of the athlete's ECG and echocardiogram is crucial, particularly when one considers the continuous expansion of preparticipation screening programmes. This review attempts to highlight ethnically determined differences in cardiovascular adaptation to exercise and provides a practical guide for the interpretation of baseline investigations in athletes of diverse ethnic backgrounds.

Cardiac adaptation to intense physical exercise is determined by factors including age, gender, body size, sporting discipline and ethnicity. Differentiating physiology from pathological conditions such as hypertrophic cardiomyopathy (HCM) is challenging, but relevant, as HCM remains the commonest cause of sudden death in young athletes. Marked electrocardiographic repolarisation changes and echocardiographic left ventricular hypertrophy have been demonstrated in athletes of black ethnicity. Such changes highlight the overlap between ‘athlete9s heart’ and morphologically mild HCM with potential for false-positive diagnoses and disqualification from competitive sport. The focus of this article is to provide practical considerations in differentiating physiological adaptation to exercise from cardiac pathology in athletes of black ethnicity.

Experiments were performed with a laminar flow wing equipped with a full span control surface to evaluate the effect of a range of simulated ice shapes on wing aerodynamic performance. The tests were conducted in the 7-ft by 10-ft wind tunnel facility at Wichita State University at airspeed of 100 mph, geometric angles of attack from -8° to +23°, Mach number of 0.134 and a Reynolds number of 3.80 million based on the mean aerodynamic chord. During the aerodynamic tests, six component force and moment measurements, control surface hinge moments and surface pressures at two spanwise stations were obtained. Simulated ice shapes tested included residual and intercycle ice shapes defined from icing tunnel tests with a mechanical deicing system installed in the wing leading edge. Full span step ice shapes simulated with quarter-rounds with heights of 2 mm and 4 mm were also tested at 1%, 3%, 5% and 8% chord to assess step ice location on aerodynamic performance. In addition, the 4-mm step ice shape was tested with sandpaper roughness of 24-grit, 40-grit and 80-grit upstream and also downstream of the step to help quantify the effect of roughness often observed with residual and intercycle ice shapes. In general, wing aerodynamic performance exhibited considerable sensitivity to ice shape configuration. The reduction in clean wing CL,stall due to the 18 simulated ice shapes tested ranged from 8.9% to 22.9% while the increase in wing CD,min ranged from 0% to 74.3%. The largest reduction in CL,stall was obtained with the 4-mm step ice at 1% chord on the wing upper surface combined with 24-grit roughness from approximately 1% to 20% chord on the upper surface. The largest increase in CD,min occurred with the 4-mm step ice at 1% chord on the wing upper surface with leading edge roughness of 24-grit extending from 1% chord on the upper surface to 1% chord on the lower surface. The simulated residual and intercycle ice shapes tested reduced clean wing CL,stall by 11.5% to 16.6%, increased clean wing CD,min by 35.0% to 49.5% and resulted in more negative pitching moments about the wing aerodynamic center. Their effect on control surface hinge moments was small. Computational fluid dynamic analysis was also performed for the wing model with the 4-mm step ice, combinations of 4mm step ice and roughness, and a simulated intercycle ice shape. The tunnel walls were included in the flow simulations performed. The analysis was performed at a geometric angle of attack of approximately 7° and airspeed of 100 mph. Overall, the agreement between analysis and experiment was good for the clean and iced wing configurations computed.

Sudden cardiac death (SCD) in an athlete is a rare yet highly visible tragedy that generates significant media attention and discussion among medical personnel, sports communities, and laypersons alike. The incidence of SCD is greater in athletes compared with their nonathletic counterparts due to the increased risk associated with strenuous exercise in the context of a quiescent cardiac abnormality. Numerous structural, electrical, and acquired cardiovascular abnormalities are capable of causing SCD, many of which can be identified during life and managed by lifestyle modifications, pharmacotherapy, and device therapy. Strategies for the prevention of SCD, including pre-participation cardiovascular screening, are endorsed by sports governing bodies, but mandatory pre-participation cardiovascular screening remains rare. Evaluation of athletes poses diagnostic difficulties, particularly differentiating between physiological adaptation to exercise, known as athlete's heart, and cardiomyopathic processes capable of causing SCD. This paper provides a detailed review regarding the etiology of SCD in young athletes and provides insight into the challenges and dilemmas faced when evaluating athletes for underlying pathological conditions.

The sudden cardiac death (SCD) of an apparently healthy young person (

Vertebral Langerhans cell histiocytosis, formerly called Histiocytosis X, is rarely seen in adults: a systematic non-quantitative review of the literature yielded only 27 cases. Vertebra plana is often associated in children, but this is not a feature in the adult population. The authors report the case of a 29-year-old woman with a two-month history of lumbar pain. Osteolysis of the right pedicle of L2 was noted on CT and MRI. Transpedicular curettage and fusion L1L3 were performed. Histopathological examination revealed Langerhans cell histiocytosis. Although rare, Langerhans cell histiocytosis should be included in the differential diagnosis of the solitary lytic vertebral lesion in the adult. Good results have been reported, in the absence of systemic manifestations, with the most conservative approach possible.

The objective of this study was to determine the prevalence of conventional risk factors in sudden arrhythmic death syndrome (SADS) probands with Brugada syndrome (BrS).Patients with BrS and previous aborted sudden cardiac death (SCD) are at high risk of recurrent events. Other universally accepted clinical features associated with higher risk include unheralded syncope and the presence of a spontaneous type 1 electrocardiogram (ECG).We analyzed reported symptoms and reviewed ECGs from SADS probands with familial diagnoses of BrS, established by cardiological evaluation, including ECG, 2-dimensional echocardiography, Holter monitoring, exercise tolerance testing, and ajmaline provocation. These cases underwent familial evaluation between 2003 and 2010.A total of 49 consecutive families with a confirmed SADS death and a diagnosis of BrS were evaluated, comprising assessment of 202 family members in total. One family had 2 members with SADS, resulting in a total of 50 probands included. Mean age of death of probands was 29.1 ± 10.6 years, with 41 males (82%) (p0.05). Antemortem ECGs were available for 5 SADS probands, 1 of which demonstrated a spontaneous type 1 pattern. In 45 probands, symptoms before death were reported reliably by family members. Of these, 9 (20%) had experienced at least 1 syncopal episode before the fatal event. Importantly, 68% of probands would not have fulfilled any current criteria for consideration of implantable cardioverter-defibrillator.The "low-risk" asymptomatic BrS group comprises the majority of SCD in this cohort. Current risk stratification would appear to be inadequate, and new markers of risk are vital.

range of -14F to 16F, and icing exposure times of 6, 10, 12, and 22.5 minutes. Ice shape traces were obtained at four inlet circumferential stations corresponding to 0 (inlet upper lip), 90, 180, and 270. Inlet leading edge ice shapes were computed with the LEWICE3D ice accretion code for the conditions investigated during the icing tunnel tests. The experimental and LEWICE3D ice shapes were compared to assess the performance of LEWICE3D in computing inlet ice accretion characteristics. Experimental and LEWICE3D ice shapes were found to be in good overall agreement, in terms of ice shape size, horn features, and icing limits, for six out of the nine cases presented in this paper. For the remaining three cases, however, the LEWICE3D shapes exhibited considerable differences with the experimental shapes.

A business jet wing model equipped with a hot-air ice protection system was tested at the NASA Glenn Icing Research Tunnel for a range of external conditions representative of inflight icing. The 2D wing model was instrumented with 76 surface pressure taps and 205 temperature and pressure sensors to monitor wing leading edge skin temperatures and bleed-air system flow properties. The main objective of the investigation was to generate an experimental database for the development and validation of simulation tools used to design and analyze thermal ice protection system. Bleed-air system performance data and runback ice shapes were documented for two piccolo configurations and a range of bleed-air mass flows and temperatures for dry and wet external flow conditions. Selected experimental results for representative cold hold (V=110 kts, =3, Ts=-22F, MVD=29m, LWC=0.69 g/m 3 ) and descent (V=194 kts, =-1, Ts=-4F, MVD=25m, LWC=0.41 g/m 3 ) flight conditions are included in this paper. The experimental results presented demonstrate the variation in wing skin temperatures and other bleed air system parameters as a function of hot-air mass flow, hot-air temperature and piccolo configuration. The runback ice accretions documented showed that the ice front advanced upstream along the airfoil upper and lower surfaces as the thermal input to the bleed air system was reduced. Runback ice shape heights measured on the wing upper surface ranged from 0 to 0.26 inches.

The beneficial effects of regular physical exercise on cardiovascular morbidity and mortality are well documented. In rare cases, however, athletes with cardiovascular abnormalities are at increased risk of exercise-related sudden cardiac death (SCD). Paradoxically, most SCDs can be attributed to cardiovascular abnormalities that can be identified during an athlete's life. Such abnormalities can be minimized by several therapeutic strategies, including insertion of an implantable cardioverter-defibrillator. Based on these considerations, the medical and sporting governing bodies recommend preparticipation cardiovascular screening (PPS) in young competitive athletes (aged

Background Careful review of published evidence has led to the postulate that the degree of lumbar lordosis may possibly influence the development and progression of spinal osteoarthritis, just as misalignment does in other joints. Spinal degeneration can ensue from the asymmetrical distribution of loads. The resultant lesions lead to a domino- like breakdown of the normal morphology, degenerative instability and deviation from the correct configuration. The aim of this study is to investigate whether a relationship exists between the sagittal alignment of the lumbar spine, as it is expressed by lordosis, and the presence of radiographic osteoarthritis. Methods 112 female subjects, aged 40-72 years, were examined in the Outpatients Department of the Orthopedics' Clinic, University Hospital of Heraklion, Crete. Lumbar radiographs were examined on two separate occasions, independently, by two of the authors for the presence of osteoarthritis. Lordosis was measured from the top of L1 to the bottom of L5 as well as from the top of L1 to the top of S1. Furthermore, the angle between the bottom of L5 to the top of S1was also measured. Results and discussion 49 women were diagnosed with radiographic osteoarthritis of the lumbar spine, while 63 women had no evidence of osteoarthritis and served as controls. The two groups were matched for age and body build, as it is expressed by BMI. No statistically significant differences were found in the lordotic angles between the two groups Conclusions There is no difference in lordosis between those affected with lumbar spine osteoarthritis and those who are disease free. It appears that osteoarthritis is not associated with the degree of lumbar lordosis.

A computational study was conducted to investigate the performance of a hot air antiicing system under dry external flow conditions. The hot air system consisted of a piccolo tube and an inner-liner skin installed inside the leading edge of a 72-in span, 60-in chord business jet wing model. A conjugate heat transfer analysis was performed with a threedimensional Navier-Stokes computer code to compute leading edge skin temperatures and hot air system internal flow properties. Simulations were conducted with a full-span model (FSM) to investigate the flow development inside the piccolo tube and with a partial-span model (PSM) to compute hot air system performance. The computational results obtained were compared with experimental data obtained from icing tunnel tests at the NASA Glenn Icing Research Tunnel. Computed leading edge skin temperatures, piccolo centerline total temperatures and pressures were found to be in good agreement with the experimental data.

This paper includes the results of a significant research program for verification of computer trajectory codes used in aircraft icing analysis. Experimental water droplet impingement data have been obtained in the NASA Lewis Research Center Icing Research Tunnel for a wide range of aircraft geometries and test conditions. The body whose impingement characteristics are required is covered at strategic locations by thin strips of moisture absorbing (blotter) paper and then exposed to an airstream containing a dyed-water spray cloud. Water droplet impingement data are extracted from the dyed blotter strips by measuring the optical reflectance of the dye deposit on the strips with an automated reflectometer. Impingement characteristics for all test geometries have also been calculated using two recently developed trajectory computer codes. Good agreement is obtained with experimental data. The experimental and analytical data show that maximum impingement efficiency and impingement limits increase with mean volumetric diameter for all geometries tested. For all inlet geometries tested, as the inlet mass flow is reduced, the maximum impingement efficiency is reduced and the location of the maximum impingement shifts toward the inlet inner cowl.

The curvature of the lumbar spine and the risk of developing either osteoporosis (OP) or osteoarthritis (OA) are influenced by many common factors. The aim of this study is to determine whether lumbar lordosis is different between patients with either disease and healthy persons. A cross-sectional, blinded, controlled design was implemented. One hundred and twelve postmenopausal women were evaluated for bone mineral density as well as undergoing spinal radiography. Lordosis measurement was performed with Cobb's method. The sample was divided in four groups: patients with OP (n = 34, L1-L5 = 40.7 degrees, L1-S1 = 54.1 degrees), patients with OA (n = 29, L1-L5 = 38 degrees, L1-S1 = 52.3 degrees), patients with both diseases (n = 20, L1-L5 = 41.8 degrees, L1-S1 = 52.3 degrees) and controls (n = 29, L1-L5 = 38.6 degrees, L1-S1 = 51.8 degrees). For all participants age, height, weight, body mass index, physical activity level and basal metabolic rate were measured and recorded. The results revealed that although the four groups have significant constitutional differences, lumbar lordosis was comparable between them. The reasons for the lack of association are discussed.

We report the case of an achondroplastic dwarf who presented with partial paraplegia due to cauda equina compression. The patient had marked thoracolumbar kyphosis and spinal stenosis at L2–L3. Although only posterior decompression is recommended in the literature for the treatment of achondroplastic patients presenting with neurological problems, a staged anterior and posterior decompression and stabilization was considered necessary for the treatment of this particular patient due to the presence of kyphosis. Satisfactory clinical results were achieved and sustained for six years following this complex operation.

Risk stratification for sudden death in Brugada syndrome and hence indications for implantation of an internal cardioverter defibrillator are based on the presence of a spontaneous type 1 electrocardiogram (ECG) pattern, in association with unheralded syncope or documented polymorphic ventricular tachycardia. Increasingly, awareness of sudden death in the young and implementation of pre-participation screening programs in sport will identify young, asymptomatic patients with the Brugada phenotype. We evaluated the predictive accuracy of symptoms, particularly unheralded syncope in victims of sudden death from Brugada syndrome. Over the past 3 years we identified 22 victims of sudden cardiac death secondary to Brugada syndrome. The diagnosis was based on sudden death with normal findings at post mortem and the identification of the type 1 Brugada ECG pattern in first-degree relatives (spontaneous or following ajmaline provocation test). All relatives underwent 12-lead ECG, echocardiography, exercise testing, 24-hour Holter monitor and biochemical tests. Cardiac magnetic resonance imaging and coronary angiography were performed when appropriate. Of the victims dying from Brugada syndrome, 15 (68%) were male. The mean age of sudden death was 30 years (range 8 –56 years) and 95% died suddenly at rest or during sleep. We interviewed first-degree relatives and partners regarding prodromal symptoms or a history of epilepsy. Only 3 out of 22 victims (14%) had significant symptoms. Specifically, 2 individuals experienced unheralded syncope and 1 suffered nocturnal seizures. Only 14% had a family history of premature sudden cardiac death. Indeed we obtained 12-lead ECGs in 3 victims taken less than 6 months prior to sudden death, which failed to reveal the typical Brugada ECG phenotype. Our results indicate that the vast majority of individuals who die from Brugada syndrome in the UK are asymptomatic and raise concerns that the absence of symptoms does not necessarily mean low risk. Better understanding of the disorder and risk stratification protocols is necessary to permit genuine reassurance in asymptomatic individuals exhibiting the Brugada phenotype.

Introduction Cardiac adaptation to intense physical exercise is associated with physiological increases in cardiac dimensions that are reflected on the EKG. The EKG changes in Caucasian athletes (WA) are established, however, there is a paucity of data in black athletes (BA) who constitute an increasing proportion of elite athletes in Western countries. We sought to identify differences (if any) in EKG characteristics between BA and WA participating in similar sporting disciplines. Methods Between 2007– 8, 222 nationally ranked male BA aged 14 –35 and 496 WA of similar age, size and range of sporting disciplines underwent a EKG and standard 2-D echocardiography. All athletes with a left ventricular wall thickness > 12mm and deep T wave inversion (> −0.2 mV) underwent Holter monitor, exercise stress test, and cardiac MRI to exclude phenotypic features of hypertrophic cardiomyopathy (HCM). Results Black athletes had a greater prevalence of voltage criteria for left ventricular hypertrophy (LVH) (57% vs 42%; p < 0.005), ST segment elevation (76% vs 33%; p < 0.001) and T wave inversions (25% vs 4%; p < 0.001) compared with WA. ST segment elevation in all athletes was confined to the anterior precordial leads but 50% BA exhibited a unique convex ST segment elevation pattern that was absent in WA. There was no correlation between T wave inversions and LVH at echocardiography or cardiac MRI. Indeed none of the BA with T wave inversions displayed any phenotypic features of HCM. Conclusion Black athletes exhibit different adaptive responses to exercise than WA. Deep T wave inversions and convex ST segment elevation are common in BA, with or without LVH and may overlap with HCM. These results have significant implications during pre-participation screening. There is the potential risk of generating a false positive diagnosis of HCM and lead to unnecessary exclusion from competitive sport, if data derived from WA, used to identify an abnormal EKG, is incorrectly extrapolated to BA.

Spinal surgery-associated rhabdomyolysis, although rare, is a life-threatening condition. Presented here is the case of a middle-aged, overweight man who underwent posterior lumbar surgery because of pain and neurogenic claudication. His postoperative course was complicated by the occurrence of rhabdomyolysis. Despite adequate treatment, acute renal failure developed as a sequela. His condition was grave enough to require the administration of intermittent hemodialysis. After a prolonged hospitalization and 5 sessions of hemodialysis, the patient achieved a full recovery. In view of the fact that rhabdomyolysis-induced acute renal failure is associated with a mortality rate of 20-50%, the outcome was favorable.

Computational and experimental investigations were conducted to evaluate the performance of a spray rig for airborne icing tanker applications. Tests were performed at the Wichita State University (WSU) 7-ft x 10-ft wind tunnel facility to assess the effects of spray nozzle number density, pattern and spacing on spray cloud plume size and uniformity. Air-atomizing multi-jet nozzles and vortex generators were incorporated into the spray rig design to enhance cloud size and uniformity. Computational fluid dynamics (CFD) analyses were conducted prior to the wind tunnel tests to evaluate the effects of vortex generators and nozzle support structure on spray cloud droplet dispersal. FAR Part 25 Appendix C and SLD spray cloud conditions were generated with a computer controlled spray system developed at WSU. Spray plume sizes were documented at an airspeed of 155 mph using a laser sheet imaging (LSI) technique. Spray cloud liquid water content (LWC) was measured with a CSIRO-King probe installed at the diffuser section of the tunnel. Three nozzle arrangements with 7, 11 and 12 nozzles placed within a circle of 24-in radius were investigated. Spray plume sizes measured at a location 10.5-ft downstream of the nozzles were approximately 5-ft in diameter for all three nozzle arrangements tested. The 11-nozzle spray rig tested provided the best overall cloud uniformity. Spray cloud LWC for the 11nozzle spray rig was 0.13 g/m 3 for a cloud median volumetric diameter (MVD) of 40 microns, and 0.47 g/m 3 for a cloud MVD of 50 microns. For large droplet spray clouds, the LWC varied from 1.20 to 1.50 g/m 3 as the cloud MVD was increased from 100 to 160 microns.

An experimental investigation of droplet impingement in the proximity of clean and iced airfoils was conducted at the NASA Glenn Droplet Imaging Flow Tunnel (DrIFT). Droplets were released using a mono-dispersed droplet generator at the tunnel inlet and were accelerated by the tunnel contraction prior to impingement on the airfoil surface. The main objective of the study was to develop and refine visualization techniques to improve understanding of large droplet splashing and breakup phenomena. It is hoped that, with better measurement techniques, more accurate physical models can be developed for the simulation of ice accretions due to supercooled large droplets (SLD). The DrIFT tunnel inlet and contraction sections were replaced by a specially designed inlet contraction section to reduce potential droplet breakup near the tunnel throat area and to minimize droplet dispersion in the test section. The original test section was also replaced with a new test section to allow better optical access for imaging droplet splashing and breakup. These tunnel improvements allowed acceleration of droplets between 40 and 370 μm in diameter to velocities of up to 135 mph without droplet breakup. The process of droplet impingement, splashing and breakup were recorded using two cameras, a Phantom v7 high-speed digital camera and a PI MAX CCD camera. The Phantom camera was also used to determine the droplet sizes produced by the mono-dispersed droplet generator.

An experimental and numerical study was performed to design a spray system for existing icing tankers to produce both Appendix C and SLD icing clouds. The study assessed the characteristics of the spray clouds generated by air-atomizing nozzles in terms of the plume size, air and water flow rates, cloud intensity and droplet size distributions. Two commercially available nozzles, single-jet and multi-jet nozzles, which can produce both Appendix C and SLD icing conditions, were evaluated using an in-house developed spray control system. The system monitors the performance of the spray nozzle and documents the volume air and water flow rates of the nozzles for a range of air and water pressures. Droplet sizes were measured using a two-component Phase Doppler Particle Analyzer (PDPA). The effect of the air speed on the spray cloud were investigated in the 7-ft x 10-ft wind tunnel at Wichita State University. The spray cloud intensity and plume sizes at several axial locations from the nozzle in the wind tunnel were measured using a laser sheet illumination technique. The experimental measurements were used to validate a 3-D numerical spray model in the FLUENT software, which was used to simulate the Appendix C and SLD clouds generated by a multi-nozzle spray rig. The simulated results from a preliminary 6-nozzle spray rig design produced an Appendix C plume diameter of approximately 31 inches, and the diameter of the SLD plume was approximately 54 inches. The validated spray model is being used to optimize the nozzle spacing in a new spray rig design in order to increase plume diameter and to improve cloud intensity distribution.

Introduction Sudden cardiac death in young athletes is commonly due to inherited cardiac diseases that can be detected during life. The International Olympic Committee (IOC) and European Society of Cardiology (ESC) recommend pre-participation screening with ECG in young athletes to detect those at risk. The 2010 ESC recommendations and Seattle criteria recommendations were developed to aid the ECG interpretation in athletes given that cardiovascular remodelling in the conditioned athlete is associated with physiological ECG changes. Antagonists of ECG inclusive pre-participation screening have questioned the high rates of false positive ECG’s in athletes despite these recommendations, as well as the cost effectiveness of such practice. The recently published refined criteria for ECG interpretation in athletes have demonstrated a significant reduction in the false positive ECG rate without compromising sensitivity of diagnosis. The aim of this study was to report the financial implications of application of the three ECG interpretation criteria in detecting potentially sinister diseases in young UK athletes. Methods Between 2011–2013, 2,493 consecutive asymptomatic and apparently healthy elite athletes aged 14–35 years underwent pre-participation screening with ECG conducted by a cardiologist at a cost of £35 per athlete. ECG interpretation was in line with 2010 ESC recommendations. Athletes with ECG abnormalities warranted further evaluation which would be facilitated in secondary care as recommended by the ESC. The Seattle criteria and refined criteria for ECG interpretation were applied to this cohort retrospectively. Results 2,493 athletes (mean age 19.8 ± 4 years, 1934 (78%) male, 2,214 white (88.9%), 72 black (3%), 227 mixed/other (8.1%)) from 23 sporting disciplines were screened. 7 athletes (0.3%) were diagnosed with a potentially sinister cardiac condition by ECG irrespective of the ECG criteria used (4 HCM, 1 LQTS, 2 WPW). The refined criteria would reduce the minimum overall cost per sinister cardiac condition identified from £31,191 to £17,459, equating to a 44% reduction. Conclusion The refined criteria for ECG interpretation could reduce the overall cost of pre-participation screening by a minimum by £39 per athlete (Table 1). In the current financial climate, the refined criteria provides a welcome cost saving practice without compromising efficacy of screening. The data is based on heavily subsidised preliminary investigations and modest tariffs of further investigations in the National Health Service (NHS); therefore the refined criteria is likely to have a greater impact in other healthcare models.

Purpose The sudden cardiac arrest (SCA) of a professional athlete is a tragic, highly publicised event with profound implications. Recent studies have demonstrated that quick and effective defibrillation has the potential to prevent sudden cardiac deaths. Of concern, a study across European football arenas revealed significant deficiencies in emergency preparations, with up to a third of arenas lacking on site automated external defibrillators (AEDs), medical action plans and cardiopulmonary resuscitation (CPR) training programmes. This study aimed to map the emergency response planning and prevention strategies across professional football clubs in England and identify potential differences between top level and lower division clubs. Methods Between June and October 2014, in collaboration with The Football Association (FA), we sent a questionnaire to the medical personnel of all 92 professional clubs across the English football league. The questionnaire covered four key areas: cardiac screening; emergency planning; provision and training of AEDs; and provision of emergency services for the players on match days. Results With a response rate of 65%, 60 clubs responded to our survey (Figure 1). All clubs participated in cardiac screening as per The FA guidelines. All clubs provided AEDs for their players not only on match days but also during training sessions. In contrast to the Premiership however, where all clubs provided AED training to designated staff, almost 30% of clubs in the lower divisions had available devices but no formal training for the staff. The majority of clubs across all divisions reported the existence of an emergency action plan for SCA but the presence of documentation was variable. Almost all clubs in the Premiership and 1 st division who had an action plan had it clearly documented, while only 78% of clubs in the Championship and 63% in 2 nd division with a plan provided formal documentation. Finally, all clubs in the Premiership and 1 st division but only 70% of clubs in Championship and 2 nd division provided an ambulance on match day. Conclusions/implications Our study indicates that the majority of clubs in England have satisfactory prevention strategies and emergency response planning. In comparison to the ARENA safety study, clubs across the English football league outperform their European counterparts as all ensured AED provision and 70% provided a documented emergency action plan. Improvements, however, are necessary to further enhance cardiovascular safety of all athletes and close the gap between the Premiership and lower divisions.

Introduction Sudden cardiac death in the young is commonly due to inherited cardiac diseases that can be detected during life. Several scientific and sporting associations recommend pre-participation screening with ECG in young athletes to detect those at risk. Antagonists have questioned the cost effectiveness of such practice and the ethics of confining screening to athletes when consideration is given to the fact that most cardiac deaths in the young affect non-athletes. This study reports the diagnostic yield and financial implications of detecting potentially sinister diseases in young individuals in the UK. Methods Between 2011–2012, 18,137 individuals nationwide aged 14–35 years underwent cardiovascular evaluation at a cost of £35 per person with a health questionnaire and physical examination (H+P) conducted by a cardiologist and an ECG interpreted in line with the 2010 ESC recommendations. On site echocardiography was performed in those considered to have abnormalities on preliminary assessment at no extra cost. Individuals requiring further evaluation were referred to secondary care. Follow up data was available in 75% of referred individuals. Results 2,786 (15%) elite athletes undergoing pre-participation screening and 15,351 (85%) self-presenting and apparently healthy general population subjects were evaluated. 7.5% (n = 209) athletes and 9.7% (n = 1,495) general population subjects were considered to have abnormalities on preliminary assessment. On site echocardiography reduced referral for further evaluation by 53% (n = 111) in athletes and 61% (n = 905) in the general population. The predominant reason for referral in both groups was an ECG abnormality. Athletes were less likely to be referred for abnormalities on H+P. The prevalence of sinister cardiac diseases was similar in both groups; however, the cost per diagnosis was twice as expensive in the general population (Table 1). Conclusion The cost of diagnosing a sudden cardiac death associated condition in the young ranges from £17,709 to £31,616. In the current financial era, this model may offer an effective alternative outside a national screening program; however, the data is based on heavily subsidised preliminary investigations and relatively modest tariffs of further evaluation in the National Health Service (NHS) and therefore such practice may not be feasible in other healthcare models.

Purpose Recommendations for interpretation of the athlete’s electrocardiogram (ECG) has evolved in recent years, namely with the European Society of Cardiology (ESC, 2010), Seattle (2013) and more recently, the Refined (2014) criteria. A principle aim of these developments has been to improve the sensitivity and specificity for identification of young athletes at risk of sudden cardiac death and reduce false-positive rates. Whether these criteria are effective in adolescents is yet to be validated. Our study aimed to compare these criteria in a large cohort of adolescent (aged 14–17 years) athletes. Methods Between July 1998–August 2012, 7993 adolescent, professional male footballers aged between 14 and 17, were assessed through pre-participation screening. This included a history, examination, 12-lead ECG and echocardiogram. A retrospective analysis of the ECG data was undertaken with the application of the ESC, Seattle and Refined criteria. Results Athletes were aged 16.1 ± 1.5 years and were all male. 87.8% were Caucasian, 10.3% were Afro-Caribbean and the remainder being Oriental and South-East Asians. 1017 (12.7%) subjects were deemed to have an abnormal ECG when the ESC criteria were applied. This compared with 312 (3.9%) athletes against the Seattle criteria (p Conclusions/implications Recent developments of recommendations for interpretation of the athlete’s ECG, most significantly through the Refined criteria, shows a reduction in the number of adolescent athletes deemed to have cardiac abnormalities. Our results suggest that current screening criteria are applicable in adolescent athletes as well as older counterparts. The Refined criteria will further improve the specificity of screening and therefore reduce the burden posed by high false-positive rates.

Purpose T wave inversion (TWI) is the electrical hallmark of cardiac conditions such as hypertrophic cardiomyopathy (HCM) or arrhythmogenic right ventricular cardiomyopathy (ARVC), which may be the substrate for sudden cardiac death in the young athlete. Such repolarization anomalies can feature on the ECG of an apparently healthy athlete and pose major diagnostic dilemmas in sports cardiology, as regular, prolonged high intensity, physical activity is associated with such repolarization changes. Athletes themselves are reluctant to detrain during the season, which makes interpreting any reversible effects of exercise on the ECG more difficult. This study aimed to investigate the effect of detraining on TWI in athletes. Methods Between 2013–2014, 36 professional footballers demonstrated TWI at mid-season ECG screenings (trained period). They were followed up during the “off-season” after a period of detraining (6–8 weeks). TWI was defined as −0.1 mV or greater 2 or more contiguous leads, in the anterior leads-V2-V3/4; inferior-II, III, aVF; or lateral-beyond V4 +/- aVL. Comparisons were drawn by 2 independent cardiologists, between trained and detrained ECG repolarization patterns. Every individual was subsequently investigated for an underlying cardiomyopathy. Results Athletes were male and aged 24.5+/-2.7 years. 27 (75%) were Afro-Caribbean and 25% Caucasian (p = 0.0141). TWI was most commonly observed in the anterior leads (n = 20, 55%), followed by inferior (n = 10, 28%) and lateral (n = 6, 17%). No Caucasian player had TWI in the lateral leads. After detraining, 16 players demonstrated resolution of anterior TWI (80%, p = 0.0293), 8 in inferior leads (80%, p = 0.2353) and 4 in the lateral leads (67%, p = 0.638) (Figure 1). All players with abnormal TWI according to consensus guidelines were comprehensively evaluated with no cardiomyopathy identified. Conclusion/implications Convincing athletes to detrain in order to interpret repolarisation anomalies is particularly difficult, due to enthusiasm for continued participation and reluctance to stop exercising. In our cohort of athletes who did detrain during the ‘off-season’, we observed resolution of TWI in the majority of athletes (both Afro-Caribbean and Caucasian) after a relatively brief period of detraining which may be deemed a physiological phenomenon. This was statistically significant in the anterior leads. However, TWI in the inferior and/or lateral leads should always raise the suspicion of an underlying cardiomyopathy, especially if persistent after detraining.

Computational water droplet impingement results for a high-lift airfoil, consisting of a flap, main and slat elements, are presented and are compared with experimental data. Droplet breakup, splashing and rebound models were used to evaluate the effects of large droplet dynamics on the impingement results. Droplet breakup effects were simulated using the Taylor Analogy Breakup (TAB) model. Large droplet splash effects were simulated with an empirical model developed at Wichita State University. A droplet rebound model is presented for computing droplet rebound mass, size, velocity and angle after a splash event. The three models were implemented into a droplet trajectory code to compute the droplet impingement distributions in the airfoil. The analyses were performed with cloud MVDs of 11, 21 and 92 µm, and α = 0° and 4°. Comparison of the simulated results with experimental measurements showed that large droplet dynamics has a significant effect on the impingement distributions in SLD clouds compared to the Appendix C clouds. Droplet splashing occurred in all three elements and droplet re-impingement was observed on the main and flap elements. Slight disagreements between experimental and simulated results were found in areas of the airfoil that experienced both droplet splashing and reimpingement. This was due to the sensitivity of the rebound model which has only been validated qualitatively due to the lack of quantitative data. In general, the breakup, splashing and rebound model models performed well as evidenced by the good agreement between simulated and experimental impingement distributions.

Ice particles shed from aircraft surfaces are a safety concern because they can damage aft mounted engines and other aircraft components. Current particle trajectory simulation methods have limited capabilities in predicting ice fragment trajectories. This is due to the random characteristics of the shed particles and lack of experimental aerodynamic data for ice fragments. This paper describes a new effort in developing a methodology for computing the trajectories of large ice particles. The methodology combines experimental aerodynamic characteristics of ice fragments, computational fluid dynamics, trajectory analysis and the Monte Carlo method to provide probability maps of shed particle footprints at desired locations. The methodology was applied to compute the trajectories of a square ice fragment and a rectangular plate shed in a three-dimensional uniform flowfield. Monte Carlo simulations were also performed where ice fragment parameters such as length, thickness, lift and drag coefficients, initial orientation, etc. were randomly changed and probability maps were computed.

This paper presents experimental results that were obtained with a prototype probe designed to measure liquid water content (LWC) in Appendix C and SLD icing cloud conditions. The LWC probe consisted of a total pressure probe, a water collector to trap' ingested water droplets, and a suction fan to provide a controlled volumetric airflow. Water droplets were collected isokinetically by the probe, and the LWC was determined from the water mass and volumetric air drawn into the probe. A water collector was developed that made use of a combination of hydrophobic fiber mesh, water adsorbent paper and desiccant materials to store the ingested water droplets. However, the water absorbed by the desiccant material was difficult to ascertain hence the dessicant material was removed from the water collector and a humidity sensor was installed inside the probe. The performance of the prototype probe was evaluated in a laboratory by injecting a known quantity of water directly into the probe inlet and comparing this to the amount adsorbed by the water collector. The results showed that the mean collection efficiency of the LWC probe was 92.1 ± 8.3% for an LWC range of 0.2 to 1.9 g/m 3 . A method for computing LWC from the relative humidity measurements inside the probe and the water collected by the water collector was developed and tested.

This paper reports on the development and calibration of a prototype probe for measuring the liquid water content of Appendix C and SLD icing cloud conditions. The conceptual design was based on a total pressure probe, water collector and suction fan. The water droplet mass that was collected iso-kinetically by the probe was weighed, and the LWC was determined from the water mass and volumetric air drawn into the probe. Initial effort had concentrated on the evaluation of different methods of capturing and storing water droplets that entered the probe. Different types of the adsorbent materials were installed into a detachable water collector to remove water droplets from an ingress water cloud via adsorption e.g. water adsorbent and blotter papers, silica gel and molecular sieve desiccants and hydrophobic B-Gon fiber mesh. The basic test methodology was to inject a known amount of water directly into the probe inlet and comparing this to the amount adsorbed by the water collector. Tests conducted in a laboratory showed that collection efficiencies of 100.8 ± 8% for LWC between 0.5 and 4.0g/m 3 were obtained. The iso-kinetic function of the probe was tested successfully in the wind tunnel at velocities between 105 and 130mph. Iso-kinetic condition was attained within 3 seconds of engaging the suction fan of the probe. NOMENCLATURE