932 research outputs found
Sort by
Real-ear acoustical characteristics of impulse sound generated by golf drivers and the estimated risk to hearing: a cross-sectional study
Objectives: This study investigated real-ear acoustical
characteristics in terms of the sound pressure levels
(SPLs) and frequency responses in situ generated from
golf club drivers at impact with a golf ball. The risk of
hearing loss caused by hitting a basket of golf balls
using various drivers was then estimated.
Design: Cross-sectional study.
Setting: The three driver clubs were chosen on the
basis of reflection of the commonality and modern
technology of the clubs. The participants were asked to
choose the clubs in a random order and hit six twopiece
range golf balls with each club. The experiment
was carried out at a golf driving range in South Wales,
UK.
Participants: 19 male amateur golfers volunteered to
take part in the study, with an age range of 19–54 years.
Outcome measures: The frequency responses and
peak SPLs in situ of the transient sound generated from
the club at impact were recorded bilaterally and
simultaneously using the GN Otometric Freefit wireless
real-ear measurement system. A swing speed radar
system was also used to investigate the relationship
between noise level and swing speed.
Results: Different clubs generated significantly different
real-ear acoustical characteristics in terms of SPL and
frequency responses. However, they did not differ
significantly between the ears. No significant correlation
was found between the swing speed and noise intensity.
On the basis of the SPLs measured in the present study,
the percentage of daily noise exposure for hitting a
basket of golf balls using the drivers described above
was less than 2%.
Conclusions: The immediate danger of noise-induced
hearing loss for amateur golfers is quite unlikely.
However, it may be dangerous to hearing if the noise
level generated by the golf clubs exceeded 116 dBA
The ARSQ: The Athletes’ Received Support Questionnaire
To address calls for context-specific measurement of social support, this article reports the development of the Athletes’ Received Support Questionnaire (ARSQ) and demonstrates initial evidence for its validity. Across four studies there was support for a four-dimensional structure reflecting emotional, esteem, informational, and tangible received support. There was also support for unidimensional and higher-order models. Further, Study 3 provided some support for convergent validity, with significant correlations between the corresponding dimensions of the ARSQ and the Inventory of Socially Supportive Behaviors. Study 4 provided evidence for the nomological validity of the ARSQ. Emotional and esteem support significantly predicted self-confidence and positive affect, and tangible support significantly moderated the relationship between stress and negative affect. Collectively, these results provide initial evidence for the validity of the ARSQ, and offer researchers flexibility to adopt either a multidimensional or aggregated approach to measuring received support
‘We are getting there slowly’: lesbian teacher experiences in the post-Section 28 environment
Prior to the subtraction of Section 28 from the 1988 Local Government Act in 2003, a substantial amount of research was published that specifically examined the experiences of lesbian physical education (PE) teachers. This article contributes to the existing academic literature by exploring the lives of lesbian, gay, bisexual and transsexual teachers working in a post-Section 28 school environment. Drawing on life history interviews of two lesbian PE teachers, we offer insights into how the abolition of Section 28 has affected their lives. Comparable to previous studies, both women reported feeling fearful of the consequences of identifying as lesbian and employed various strategies in order to maintain a divide between their public and private lives so as to conceal their sexual identities from colleagues, pupils and parents. However, in contrast to much of the previous literature, we found that the teachers in this study also identified with narratives of resistance. Despite being fearful of coming out at work, they nevertheless remained committed to coming out when the context is appropriate, to challenging the heteronormative symbolic order configured around the heterosexual/homosexual binary and to more proactively promoting sexual diversity and tolerance in schools
Ventricular structure, function, and mechanics at high altitude: chronic remodeling in Sherpa vs. short-term lowlander adaptation
Short-term, high-altitude (HA) exposure raises pulmonary artery systolic pressure (PASP) and decreases left-ventricular (LV) volumes. However, relatively little is known of the long-term cardiac consequences of prolonged exposure in Sherpa, a highly adapted HA population. To investigate short-term adaptation and potential long-term cardiac remodeling, we studied ventricular structure and function in Sherpa at 5,050 m (n = 11; 31 ± 13 yr; mass 68 ± 10 kg; height 169 ± 6 cm) and lowlanders at sea level (SL) and following 10 ± 3 days at 5,050 m (n = 9; 34 ± 7 yr; mass 82 ± 10 kg; height 177 ± 6 cm) using conventional and speckle-tracking echocardiography. At HA, PASP was higher in Sherpa and lowlanders compared with lowlanders at SL (both P < 0.05). Sherpa had smaller right-ventricular (RV) and LV stroke volumes than lowlanders at SL with lower RV systolic strain (P < 0.05) but similar LV systolic mechanics. In contrast to LV systolic mechanics, LV diastolic, untwisting velocity was significantly lower in Sherpa compared with lowlanders at both SL and HA. After partial acclimatization, lowlanders demonstrated no change in the RV end-diastolic area; however, both RV strain and LV end-diastolic volume were reduced. In conclusion, short-term hypoxia induced a reduction in RV systolic function that was also evident in Sherpa following chronic exposure. We propose that this was consequent to a persistently higher PASP. In contrast to the RV, remodeling of LV volumes and normalization of systolic mechanics indicate structural and functional adaptation to HA. However, altered LV diastolic relaxation after chronic hypoxic exposure may reflect differential remodeling of systolic and diastolic LV function.
exposure to high altitude (HA) challenges the cardiovascular system to meet the metabolic demand for oxygen (O2) in an environment where arterial O2 content is markedly reduced. The drop in arterial O2 has both direct and indirect consequences for the heart, including depressed inotropy of cardiac muscle (40, 44), changes in blood volume and viscosity, and vasoconstriction of the pulmonary arteries (33). Despite these broad physiological changes, which have been reviewed previously (28, 49), there is evidence that the heart copes relatively well at HA (29, 34).
Short-term HA exposure in lowland natives is characterized by a decreased plasma volume (PV), an increased sympathetic nerve activity, and pulmonary vasoconstriction (17, 30, 37), all of which have considerable impact on cardiac function and in time, could stimulate cardiac remodeling. Himalayan native Sherpa, who are of Tibetan lineage and have resided at HA for ∼25,000 yr (2), are well adapted to life at HA, demonstrating greater lung-diffusing capacity (11) and an absence of polycythemia compared with acclimatized lowlanders (4). Previous studies have also reported Sherpa to have higher maximal heart rates (HRs) and only moderate pulmonary hypertension compared with lowlanders at HA (11, 25). Due to their longevity at HA, Sherpa provide an excellent model to investigate the effects of chronic hypoxic exposure. Despite this, neither the acute nor lifelong effects of HA on right- and left-ventricular (RV and LV, respectively) structure and function have been fully assessed in lowlanders or the unique Sherpa population.
Due to the unique arrangement of myofibers, cardiac form and function are intrinsically linked, as reflected in the cardiac mechanics (LV twist and rotation and ventricular strain) that underpin ventricular function. In response to altered physiological demand, ventricular mechanics acutely change (16, 41) and chronically remodel (31, 42) to reduce myofiber stress and achieve efficient ejection (5, 47). Therefore, concomitant examination of myocardial mechanics and ventricular structure in both the acute and chronic HA setting will provide novel insight into human adaptation to hypoxia.
To investigate the effects of chronic hypoxic exposure, we compared ventricular volumes and mechanics in Sherpa at 5,050 m with lowlanders at sea level (SL). In addition, to reveal potential stimuli for remodeling and to examine the time course of adaptation, we compared Sherpa with lowlanders after short-term HA exposure.
We hypothesized that: 1) Sherpa would exhibit smaller LV volumes and a higher RV/LV ratio than lowlanders at SL, 2) LV mechanics in Sherpa will closely resemble those of lowlanders at SL, and 3) following partial acclimatization to HA, LV volumes would be reduced in lowlanders and LV mechanics acutely increased
Ceramics studio to podiatry clinic: The impact of multi-media resources in the teaching of practical skills across diverse disciplines
This paper draws on the experiences of students from two vastly different disciplines to both explore the theoretical background supporting the use of multimedia resources to teach practical skills and provide a qualitative evaluation of student perceptions and experiences of using bespoke resources. Within ceramics and podiatry, practical skills are traditionally taught via an apprenticeship model within small groups. We explore the practical and pedagogic benefits of developing bespoke multimedia resources to teach practical skills, identifying common themes from these disparate discipline areas. Student focus groups revealed that, practically, the opportunity for repeated viewing at convenient times promoted less reliance on lecturers and better preparation prior to practical demonstrations. Pedagogically, time for reflection and sense making underpinned an increase in confidence which in turn led to increased creativity. The student voice was also used to identify recommendations and challenges driving future change
Predicted 10-year risk of cardiovascular disease is influenced by the risk equation adopted: a cross-sectional analysis
Background Validated risk equations are currently recommended to assess individuals to determine those at ‘high risk’ of cardiovascular disease (CVD). However, there is no longer a risk ‘equation of choice’.
Aim This study examined the differences between four commonly-used CVD risk equations.
Design and setting Cross-sectional analysis of individuals who participated in a workplace-based risk assessment in Carmarthenshire, south Wales.
Method Analysis of 790 individuals (474 females, 316 males) with no prior diagnosis of CVD or diabetes. Ten-year CVD risk was predicted by entering the relevant variables into the QRISK2, Framingham Lipids, Framingham BMI, and JBS2 risk equations.
Results The Framingham BMI and JBS2 risk equations predicted a higher absolute risk than the QRISK2 and Framingham Lipids equations, and CVD risk increased concomitantly with age irrespective of which risk equation was adopted. Only a small proportion of females (0–2.1%) were predicted to be at high risk of developing CVD using any of the risk algorithms. The proportion of males predicted at high risk ranged from 5.4% (QRISK2) to 20.3% (JBS2). After age stratification, few differences between isolated risk factors were observed in males, although a greater proportion of males aged ≥50 years were predicted to be at ‘high risk’ independent of risk equation used.
Conclusions Different risk equations can influence the predicted 10-year CVD risk of individuals. More males were predicted at ‘high risk’ using the JBS2 or Framingham BMI equations. Consideration should also be given to the number of isolated risk factors, especially in younger adults when evaluating CVD risk
‘Once a Local Surfer, Always a Local Surfer’: Local Surfing Careers in a Southwest English Village
This article reports on findings from an ethnographic study (2008–09) conducted in a village with a significant population of local surfers in Cornwall (Southwest England). Stimulated by Goffman's (1961) interpretation of the concept of career and elaborated by the work of Stebbins (1970) on “subjective career,” Stebbins's (1982) framework of “serious leisure” and “serious leisure career” (Stebbins, 2005), we identify moments from local surfer careers lived in this community setting. We suggest that similar to findings from other subcultural studies on sports careers the local surfing career in this context contains shared experiential stages: the nurtured stage, the possible competitive stage, the serious leisure traveller stage, the responsible stage, and the legends stage. We conclude that the shared experiences and pathways of a local surfing career can play a positive cultural role, not just for individuals but also for the construction and maintenance of local community life
The Role of Whole Blood Impedance Aggregometry and Its Utilisation in the Diagnosis and Prognosis of Patients with Systemic Inflammatory Response Syndrome and Sepsis in Acute Critical Illness
Objective:
To assess the prognostic and diagnostic value of whole blood impedance aggregometry in patients with sepsis and SIRS and to compare with whole blood parameters (platelet count, haemoglobin, haematocrit and white cell count).
Methods:
We performed an observational, prospective study in the acute setting. Platelet function was determined using whole blood impedance aggregometry (multiplate) on admission to the Emergency Department or Intensive Care Unit and at 6 and 24 hours post admission. Platelet count, haemoglobin, haematocrit and white cell count were also determined.
Results:
106 adult patients that met SIRS and sepsis criteria were included. Platelet aggregation was significantly reduced in patients with severe sepsis/septic shock when compared to SIRS/uncomplicated sepsis (ADP: 90.7±37.6 vs 61.4±40.6; p<0.001, Arachadonic Acid 99.9±48.3 vs 66.3±50.2; p = 0.001, Collagen 102.6±33.0 vs 79.1±38.8; p = 0.001; SD ± mean)). Furthermore platelet aggregation was significantly reduced in the 28 day mortality group when compared with the survival group (Arachadonic Acid 58.8±47.7 vs 91.1±50.9; p<0.05, Collagen 36.6±36.6 vs 98.0±35.1; p = 0.001; SD ± mean)). However haemoglobin, haematocrit and platelet count were more effective at distinguishing between subgroups and were equally effective indicators of prognosis. Significant positive correlations were observed between whole blood impedance aggregometry and platelet count (ADP 0.588 p<0.0001, Arachadonic Acid 0.611 p<0.0001, Collagen 0.599 p<0.0001 (Pearson correlation)).
Conclusions:
Reduced platelet aggregometry responses were not only significantly associated with morbidity and mortality in sepsis and SIRS patients, but also correlated with the different pathological groups. Whole blood aggregometry significantly correlated with platelet count, however, when we adjust for the different groups we investigated, the effect of platelet count appears to be non-significant
Relative age effect in netball: a qualitative investigation
The purpose of the present study was to investigate the experiences of international netball players born in different parts of the school year. A total of thirteen international netball players aged 24 to 52 were interviewed (six born in the first half of the school year and seven born in the second half). A qualitative analysis of the interview data was performed using a combination of deductive and inductive analyses. The analysis focussed on five broad themes: participation motives, attrition motives, age issues, support and location issues. The two groups of players experienced similar participation motives and support from coaches, family, friends and peers. Age issues were experienced by both groups of players. Location effects and the need to balance netball with other commitments were also experienced by both groups of players. There were two differences between the two groups with all seven of the players born in the second half of the school year experiencing performance and social attrition motives. These were experienced by 3 and 4 of the 6 players born in the first half of the school year respectively. Coaches and national governing bodies need to be aware of the attrition motives experienced by players, especially those who live some distance from main netball centres. An understanding of the performance attrition motives experienced specifically by players born in the second half of the school year could help coaches to nurture talented players
Conduit artery structure and function in lowlanders and native highlanders: relationships with oxidative stress and role of sympathoexcitation
Research detailing the normal vascular adaptions to high altitude is minimal and
often confounded by pathology (e.g. chronic mountain sickness) and methodological issues.
We examined vascular function and structure in: (1) healthy lowlanders during acute hypoxia and prolonged ( 2 weeks) exposure to high altitude, and (2) high-altitude natives at 5050 m (highlanders). In 12 healthy lowlanders (aged 32 ± 7 years) and 12 highlanders(Sherpa; 33 ± 14 years) we assessed brachial endothelium-dependent flow-mediated dilatation(FMD), endothelium-independent dilatation (via glyceryl trinitrate; GTN), common carotid intima–media thickness (CIMT) and diameter (ultrasound), and arterial stiffness via pulse wave velocity (PWV; applanation tonometry). Cephalic venous biomarkers of free radical-mediated lipid peroxidation (lipid hydroperoxides, LOOH), nitrite (NO2 –) and lipid soluble antioxidants were also obtained at rest. In lowlanders, measurements were performed at sea level (334 m) and between days 3–4 (acute high altitude) and 12–14 (chronic high altitude) following arrival to 5050 m. Highlanders were assessed once at 5050 m. Compared with sea level, acute high altitude reduced lowlanders’ FMD (7.9 ± 0.4 vs. 6.8 ± 0.4%; P = 0.004) and GTN-induced dilatation (16.6 ± 0.9 vs. 14.5 ± 0.8%; P = 0.006), and raised central PWV (6.0 ± 0.2 vs. 6.6 ± 0.3 m s−1; P = 0.001). These changes persisted at days 12–14, and after allometricallyscaling FMD to adjust for altered baseline diameter. Compared to lowlanders at sea level and high altitude, highlanders had a lower carotid wall:lumen ratio ( 19%, P 0.04), attributable to a narrower CIMT and wider lumen. Although both LOOH and NO2 – increased with high altitude in lowlanders, only LOOH correlated with the reduction in GTN-induced dilatation
evident during acute (n = 11, r=−0.53) and chronic (n = 7, r=−0.69; P 0.01) exposure to 5050 m. In a follow-up, placebo-controlled experiment (n=11 healthy lowlanders) conducted in a normobaric hypoxic chamber (inspiredO2 fraction (FIO2 )=0.11; 6 h), a sustained reduction in FMD was evident within 1 h of hypoxic exposure when compared to normoxic baseline (5.7±1.6 vs. 8.0 ±1.3%; P < 0.01); this decline in FMD was largely reversed following α1-adrenoreceptor blockade. In conclusion, high-altitude exposure in lowlanders caused persistent impairment in vascular function, which was mediated partially via oxidative stress and sympathoexcitation. Although a lifetime of high-altitude exposure neither intensifies nor attenuates the impairments seen with short-term exposure, chronic high-altitude exposure appears to be associated with arterial remodelling