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233 results on '"GRANT, C. C."'

1. Combining BRITE and ground-based photometry for the Beta Cephei star Nu Eridani: impact on photometric pulsation mode identification and detection of several g modes

Author

Handler, G., Rybicka, M., Popowicz, A., Pigulski, A., Kuschnig, R., Zoclonska, E., Moffat, A. F. J., Weiss, W. W., Grant, C. C., Pablo, H., Whittaker, G. N., Rucinski, S. M., Ramiaramanantsoa, T., Zwintz, K., and Wade, G. A.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We report a simultaneous ground and space-based photometric study of the Beta Cephei star Nu Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time-series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that the three dominant pulsation modes of Nu Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy., Comment: 11 pages, 5 figures, 4 tables, accepted for publication in MNRAS

Published
2016
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2. The BRITE Constellation nanosatellite mission: Testing, commissioning and operations

Author

Pablo, H., Whittaker, G. N., Popowicz, A., Mochnacki, S. M., Kuschnig, R., Grant, C. C., Moffat, A. F. J., Rucinski, S. M., Matthews, J. M., Schwarzenberg-Czerny, A., Handler, G., Weiss, W. W., Baade, D., Wade, G. A., Zoclonska, E., Ramiaramanantsoa, T., Unterberger, M., Zwintz, K., Pigulski, A., Rowe, J., Koudelka, O., Orleanski, P., Pamyatnykh, A., Neiner, C., Wawrzaszek, R., Marciniszyn, G., Romano, P., Wozniak, G., Zawistowski, T., and Zee, R. E.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

BRITE (BRIght Target Explorer) Constellation, the first nanosatellite mission applied to astrophysical research, is a collaboration among Austria, Canada and Poland. The fleet of satellites (6 launched, 5 functioning) performs precise optical photometry of the brightest stars in the night sky. A pioneering mission like BRITE - with optics and instruments restricted to small volume, mass and power in several nanosatellites, whose measurements must be coordinated in orbit - poses many unique challenges. We discuss the technical issues, including problems encountered during on-orbit commissioning (especially higher-than expected sensitivity of the CCDs to particle radiation). We describe in detail how the BRITE team has mitigated these problems, and provide a complete overview of mission operations. This paper serves as a template for how to effectively plan, build and operate future low-cost niche-driven space astronomy missions., Comment: 54 pages, 12 figures, accepted by PASP

Published
2016
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3. The roAp star $\alpha$ Circini as seen by BRITE-Constellation

Author

Weiss, W. W., Fröhlich, H. -E., Pigulski, A., Popowicz, A., Huber, D., Kuschnig, R., Moffat, A. F. J., Matthews, J. M., Saio, H., Schwarzenberg-Czerny, A., Grant, C. C., Koudelka, O., Lüftinger, T., Rucinski, S. M., Wade, G. A., Alves, J., Guedel, M., Handler, G., Mochnacki, St., Orleanski, P., Pablo, B., Pamyatnykh, A., Ramiaramanantsoa, T., Rowe, J., Whittaker, G., Zawistowski, T., Zocłonska, E., and Zwintz, K.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We report on an analysis of high-precision, multi-colour photometric observations of the rapidly-oscillating Ap (roAp) star $\alpha$ Cir. These observations were obtained with the BRITE-Constellation, which is a coordinated mission of five nanosatellites that collects continuous millimagnitude-precision photometry of dozens of bright stars for up to 180 days at a time in two colours (Johnson B and R). BRITE stands for BRight Target Explorer. The object $\alpha$ Cir is the brightest roAp star and an ideal target for such investigations, facilitating the determination of oscillation frequencies with high resolution. This star is bright enough for complementary interferometry and time-resolved spectroscopy. Four BRITE satellites observed $\alpha$ Cir for 146 d or 33 rotational cycles. Phasing the photometry according to the 4.4790 d rotational period reveals qualitatively different light variations in the two photometric bands. The phased red-band photometry is in good agreement with previously-published WIRE data, showing a light curve symmetric about phase 0.5 with a strong contribution from the first harmonic. The phased blue-band data, in contrast, show an essentially sinusoidal variation. We model both light curves with Bayesian Photometric Imaging, which suggests the presence of two large-scale, photometrically bright (relative to the surrounding photosphere) spots. We also examine the high-frequency pulsation spectrum as encoded in the BRITE photometry. Our analysis establishes the stability of the main pulsation frequency over the last 20 years, confirms the presence of frequency f7, which was not detected (or the mode not excited) prior to 2006, and excludes quadrupolar modes for the main pulsation frequency., Comment: 10 pages, 11 figures, accepted by Astronomy & Astrophysics

Published
2016
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4. BRITE-Constellation: nanosatellites for precision photometry of bright stars

Author

Weiss, W. W., Rucinski, S. M., Moffat, A. F. J., Schwarzenberg-Czerny, A., Koudelka, O. F., Grant, C. C., Zee, R. E., Kuschnig, R., Mochnacki, St., Matthews, J. M., Orleanski, P., Pamyatnykh, A., Pigulski, A., Alves, J., Guedel, M., Handler, G., Wade, G. A., Zwintz, K., CCD, and Teams, Photometry Tiger

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

BRITE-Constellation (where BRITE stands for BRIght Target Explorer) is an international nanosatellite mission to monitor photometrically, in two colours, the brightness and temperature variations of stars generally brighter than mag(V) ~ 4, with precision and time coverage not possible from the ground. The current mission design consists of six nanosats (hence Constellation): two from Austria, two from Canada, and two from Poland. Each 7 kg nanosat carries an optical telescope of aperture 3 cm feeding an uncooled CCD. One instrument in each pair is equipped with a blue filter, the other with a red filter. Each BRITE instrument has a wide field of view (~24 degrees), so up to about 15 bright stars can be observed simultaneously, sampled in 32 pixel x 32 pixel sub-rasters. Photometry of additional fainter targets, with reduced precision but thorough time sampling, will be possible through onboard data processing. The BRITE sample is dominated by the most intrinsically luminous stars: massive stars seen at all evolutionary stages, and evolved medium-class stars at the very end of their nuclear burning phases. The goals of BRITE-Constellation are to (1) measure p- and g-mode pulsations to probe the interiors and ages of stars through asteroseismology; (2) look for varying spots on the stars surfaces carried across the stellar disks by rotation, which are the sources of co-rotating interaction regions in the winds of the most luminous stars, probably arising from magnetic subsurface convection; and (3) search for planetary transits., Comment: 23 pages, 12 figures, accepted for publication in the PASP

Published
2014
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5. BRITE-Constellation: Nanosatellites for Precision Photometry of Bright Stars

Author

Weiss, W. W., Moffat, A. F. J., Schwarzenberg-Czerny, A., Koudelka, O. F., Grant, C. C., Zee, R. E., Kuschnig, R., Mochnacki, St., Rucinski, S. M., Matthews, J. M., Orleanski, P., Pamyatnykh, A., Pigulski, A., Alves, J., Guedel, M., Handler, G., Wade, G. A., and Scholtz, A. L.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

BRITE-Constellation (where BRITE stands for BRIght Target Explorer) is an international nanosatellite mission to monitor photometrically, in two colours, brightness and temperature variations of stars brighter than V = 4. The current mission design consists of three pairs of 7 kg nanosats from Austria, Canada and Poland carrying optical telescopes and CCDs. One instrument in each pair is equipped with a blue filter; the other, a red filter. The first two nanosats are UNIBRITE, designed and built by University of Toronto Institute for Aerospace Studies - Space Flight Laboratory and its twin, BRITE-Austria, built by the Technical University Graz with support of UTIAS-SFL. They were launched on 25 February 2013 by the Indian Space Agency under contract to the Canadian Space Agency into a low-Earth dusk-dawn polar orbit., Comment: 2 page abstract of a full paper to be submitted

Published
2013
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8. Diets of Southern African Bovidae: Stable Isotope Evidence

Author

Sponheimer, Matt, Lee-Thorp, Julia A., DeRuiter, Darryl J., Smith, Jeannette M., van der Merwe, Nikolaas J., Reed, Kaye, Grant, C. C., Ayliffe, Linda K., Robinson, Todd F., Heidelberger, Cory, and Marcus, Warren

Published
2003

16. Investigation of the knowledge of South African high school rugby coaches on concussion and the return-to-play protocol.

Author

Abel, N. C., Grant, C. C., and van Rensburg, D. C. Janse

Subjects
*BRAIN concussion, *SCHOOL size, *HIGH schools, *RUGBY football, *BRAIN injuries
Abstract

Background: Coaches are pivotal in the management of concussed players. Assessing the knowledge of high school rugby coaches with regard to concussion management will enable relevant future education on this topic to be covered. Objectives: To investigate the knowledge of South African high school rugby coaches on concussion symptom recognition, knowledge and stepwise return-to-play (RTP) protocols. Methods: A cross-sectional descriptive study involving 143 first team, high school rugby coaches was completed via an electronic questionnaire. Independent variables included coach demographics, qualifications, experience, BokSmart accreditation, and school size. Dependent variables included knowledge scores on concussion symptoms, general concussion knowledge, stepwise RTP and Maddocks questions. Relationships between total scores for different demographic groupings were established using non-parametric techniques. Results: The coaches had high general, symptom and overall concussion knowledge scores (77% - 80%) in contrast with low RTP scores (62%) and very low Maddocks questions knowledge scores (26%). The 35-44-year age group received top scores for symptom recognition (p=0.034) and total concussion knowledge (p=0.041). Larger category school coaches (p=0.008) and BokSmart accredited coaches (p=0.041) outperformed all other coaches in general concussion knowledge and total knowledge, respectively. However, respondents were not familiar with emotional symptoms or the importance of cognitive rest after a concussion. Educational programmes were the most popular knowledge source for coaches. Conclusion: In general, coaches presented with good general concussion knowledge but lesser expertise on emotional symptoms, cognitive rest and RTP management. Modifiable predictors of knowledge included the expansion of BokSmart accreditation, focussing information sessions on smaller rugby size schools and the education of coaches younger than 35 years or older than 45 years of age. [ABSTRACT FROM AUTHOR]

Published
2022
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24. Anterior cruciate ligament injuries of the knee: Patterns of association between the mechanism of injury and pathology visualised on magnetic resonance imaging

Author

Strauss, G L, Janse van Rensburg, D C, Grant, C C, Jansen van Rensburg, A, Velleman, M D, and Fletcher, L

Subjects
prevention, knee injury, mechanism, association, pathology, MRI scan, prevention, association, MRI scan, mechanism, pathology, musculoskeletal system, human activities, knee injury
Abstract

Background: Anterior cruciate ligament (ACL) injuries are common among athletes and the general public. These injuries may lead to significant absence from all activities with associated financial and social burdens for the patient. No definitive association has been described between the mechanism of injury and the pathology to enable the implementation of preventative measures to limit these injuries.Aim: To determine whether there is an association between the mechanism of injury and the pathology seen on a magnetic resonance imaging (MRI) scan in ACL injuries.Methods: This was a cross-sectional analytical study. Eighty-seven male patients with an ACL injury and who had an MRI scan of the knee within the last two years participated in this study. Participants were contacted to give their informed consent to participate in this study. The mechanism of injury and the pathology seen on the MRI scan was noted and categorised into different groups of injuries and associated pathologies. Statistical analyses included summaries of the data and a test for the association between the mechanism of injury and the pathology. Since there were multiple pathology responses to each mechanism, a modified version of the chi-square test for independence was used. A five percent level of significance was specified.Results: MRI scans of ACL injuries indicated that the mechanism of a solid foot plant with rotation of the knee has a greater tendency to be associated with medial meniscal injuries (77%). There was also a 54% possibility for it to be associated with lateral meniscal injuries. A solid foot plant with a valgus stress on the knee showed a higher incidence of associated medial collateral ligament (MCL) injuries (41%) and femoral bone bruising (62%). These two mechanisms of injury are the most common in ACL injuries and contribute to the clinical significance found in this study. The p-value was, however, not statistically significant (p=0.44, chi-square value=20.27, df=45) for any association between the pathology and the mechanism of injury.Conclusion: Some injury mechanisms causing an ACL injury were more common than others and had more associated pathologies. The most common mechanism of injury noted in this study was a solid foot plant with either rotation of the knee or valgus stress on the knee. Strengthening the tissue structures involved in those movement patterns causing these mechanisms can possibly limit future ACL injuries in athletes and the general public.Keywords: knee injury, mechanism, association, pathology, MRI scan, prevention

Published
2018

26. The prevalence, risk factors predicting injury and the severity of injuries sustained during competition in professional mixed martial arts in Africa

Author

Venter, S, Janse Van Rensburg, D C, Fletcher, L, and Grant, C C

Subjects
concussion, return-to-play, mixed martial arts
Abstract

BACKGROUND: Professional mixed martial arts (MMA) has gained international popularity. No African-based studies have reported the prevalence or severity of injuries, risk factors associated with injuries or return-to-play (RTP) time. OBJECTIVES: To determine the prevalence of injuries and associated risk factors, as well as severity of injuries sustained by professional male MMA athletes competing at the Extreme Fighting Championships Africa (EFC Africa) from 2010 to 2014. METHODS: Permission to do the study and the medical records of all professional events (2010 - 2014) were obtained from EFC Africa. Data were obtained from 173 male competitors aged 18 to 44 years, who had participated in 300 professional MMA fights. Results from this prospective cohort study were compared to a similar study done in the United States of America (USA). An injury was defined as any damage to an athlete's body that needed the attention of the ringside physician. Statistical analyses included descriptive statistics and a stepwise logistic regression. Odds of an injury were predicted with six independent variables: fight outcome, age, weight division, number of fights, injuries in the preceding fight and years of fighter experience. RESULTS: Head, face and neck injuries were most common (22%), followed by traumatic brain injuries (knockouts) (6%). Losing a fight was a significant predictor of injury when using the stepwise logistic regression model (p=0.040). The odds ratio indicated that a preceding fight injury almost doubled the risk of injury in the following fight (OR 1.91; p= 0.163). Traumatic brain injuries (TBIs) in this study of African-based competitions (6%) were substantially higher than reported in the American study (1.8%). CONCLUSION: Head, neck and face injuries are common in African fighters. The high rate of TBIs in African competition compared to the USA study is concerning. This could reflect superior refereeing in the USA group, as fights may be ended sooner by stoppage. Further investigation of injury trends and preventative measures should be studied to reduce the incidence of injuries during African competitions.

Published
2017

27. Corticosteroids in sports-related injuries: Friend or Foe

Author

Rotunno, A, Rensburg, D C Janse van, Grant, C C, and Rensburg, A Jansen van

Subjects
Steroid hormones, athlete, sports, injury, inflammation
Abstract

Corticosteroids act as potent anti-inflammatory drugs and have been used in various sport settings for the treatment of both acute and chronic injuries. Basic physiology and mechanisms of action for gluco- and mineralocorticoids are discussed. Methods of administration, the action on the inflammatory response, and potential short and long-term side effects of corticosteroid use are also deliberated. More specifically, corticosteroid use in the treatment and management of sport-related injuries are discussed, elucidating on the ethical boundaries and anti-doping regulations pertaining to corticosteroid use in sports, as well as putting forth suggestions for the use of local steroid injections and their contraindications. In conclusion, it was found that, despite some controversy in the use of corticosteroid treatment in the sports environment, little empirical evidence exists that could conclusively rule for or against its use. It is however clear that, if clinically justified, there is a significant role for corticosteroid treatment in the realm of sports injury and notably with a relatively low risk profile, if administered correctly.Keywords: Steroid hormones, athlete, sports, injury, inflammation.

Published
2016

32. Iliopsoas haematoma in a rugby player

Author

Janse van Rensburg, D C, Strauss, O, Velleman, M D, Jansen van Rensburg, A, and Grant, C C

Abstract

Traumatic iliopsoas haematoma is a serious complication of haemorrhage disorders rarely seen in young healthy athletes. It is mostly described in patients on anticoagulant therapy and commonly associated with various degrees of femoral nerve palsy. A 22-year-old male rugby player presented with severe onset of pain in the lower back, right hip flexor/pelvic area following a tackle during a rugby match. Magnetic resonance imaging identified a distinct, hyperechoic heterogeneous mass within the right iliopsoas muscle, confirming a diagnosis of iliopsoas haematoma. The case resolved completely after conservative medical treatment in addition to a period of rest and intense active physical therapy. This case study reports the rare diagnosis of an uncomplicated iliopsoas haematoma following a sports injury in a young athlete.

Published
2016

34. Non-traumatic injury profile of amateur cyclists

Author

van der Walt, A, Janse van Rensburg, D C, Fletcher, L, Grant, C C, and van der Walt, A J

Subjects
body regions, human activities
Abstract

Background. Non-traumatic bicycle injuries are common. However, research available on non-traumatic injuries in amateur cyclists is more than a decade old, and most of the research on this topic has been done in Europe and America on professional cyclists in multi-day cycling events. An understanding of the common injuries may lead to appropriate prevention intervention.Objective. To determine the incidence of overuse injuries in amateur cyclists preparing for participation in a 1-day cycle challenge.Methods. A questionnaire was emailed to participants of the 2012 Momentum 94.7 Cycle Challenge, which amateur participants ≥18 years old were invited to complete. Data on demographics, training habits and the participants’ injury profile in the preceding year were collected.Results. Of the 3 300 respondents, 75% were male and 59% were between 30 and 50 years old. Non-traumatic injury, pain or neurological symptoms were reported by 88% of the respondents. The percentages of all respondents who experienced problems in the following anatomical areas were as follows: neck 34%, back 41%, hand/wrist 41%, buttock/perineum 41%, hip 7%, knee 33% and foot/ankle 24%. Knee pain was responsible for the need to stop training for the largest percentage of respondents. Neurological complaints were common in respondents who experienced neck, back, hand/wrist, buttock/perineum and foot/ankle problems.Conclusion. Non-traumatic injuries in amateur cyclists are common, with back, hand/wrist and buttock/perineal symptoms the most frequent problems. Knee problems caused the greatest need to stop training and seek medical help.

Published
2015

35. TheBRITEConstellation Nanosatellite Mission: Testing, Commissioning, and Operations

Author

Pablo, H., primary, Whittaker, G. N., additional, Popowicz, A., additional, Mochnacki, S. M., additional, Kuschnig, R., additional, Grant, C. C., additional, Moffat, A. F. J., additional, Rucinski, S. M., additional, Matthews, J. M., additional, Schwarzenberg-Czerny, A., additional, Handler, G., additional, Weiss, W. W., additional, Baade, D., additional, Wade, G. A., additional, Zocłońska, E., additional, Ramiaramanantsoa, T., additional, Unterberger, M., additional, Zwintz, K., additional, Pigulski, A., additional, Rowe, J., additional, Koudelka, O., additional, Orleański, P., additional, Pamyatnykh, A., additional, Neiner, C., additional, Wawrzaszek, R., additional, Marciniszyn, G., additional, Romano, P., additional, Woźniak, G., additional, Zawistowski, T., additional, and Zee, R. E., additional

Published
2016
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36. Combining BRITE and ground-based photometry for the β Cephei star ν Eridani: impact on photometric pulsation mode identification and detection of several g modes

Author

Handler, G., primary, Rybicka, M., additional, Popowicz, A., additional, Pigulski, A., additional, Kuschnig, R., additional, Zocłońska, E., additional, Moffat, A. F. J., additional, Weiss, W. W., additional, Grant, C. C., additional, Pablo, H., additional, Whittaker, G. N., additional, Ruciński, S. M., additional, Ramiaramanantsoa, T., additional, Zwintz, K., additional, and Wade, G. A., additional

Published
2016
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37. Childhood pneumonia and crowding, bed-sharing and nutrition: a case-control study from The Gambia

Author

Howie, S. R. C., primary, Schellenberg, J., additional, Chimah, O., additional, Ideh, R. C., additional, Ebruke, B. E., additional, Oluwalana, C., additional, Mackenzie, G., additional, Jallow, M., additional, Njie, M., additional, Donkor, S., additional, Dionisio, K. L., additional, Goldberg, G., additional, Fornace, K., additional, Bottomley, C., additional, Hill, P. C., additional, Grant, C. C., additional, Corrah, T., additional, Prentice, A. M., additional, Ezzati, M., additional, Greenwood, B. M., additional, Smith, P. G., additional, Adegbola, R. A., additional, and Mulholland, K., additional

Published
2016
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39. Interactive effects of age and respiratory virus on severe lower respiratory infection.

Author

Prasad, N, Trenholme, A A, Huang, Q S, Thompson, M G, Pierse, N, Widdowson, M A, Wood, T, Seeds, R, Taylor, S, Grant, C C, Newbern, E C, and SHIVERS team

Abstract

We investigated risk factors for severe acute lower respiratory infections (ALRI) among hospitalised children 8 months were at greater risk from influenza-associated ICU admissions and long hospital stay. Children with ADV had increased LOS across all ages. In the first 2 years of life, the effects of different viruses on ALRI severity varies with age. Our findings help to identify specific ages that would most benefit from virus-specific interventions such as vaccines and antivirals. [ABSTRACT FROM AUTHOR]

Published
2018
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40. The roAp starα Circinus as seen by BRITE-Constellation

Author

Weiss, W. W., primary, Fröhlich, H.-E., additional, Pigulski, A., additional, Popowicz, A., additional, Huber, D., additional, Kuschnig, R., additional, Moffat, A. F. J., additional, Matthews, J. M., additional, Saio, H., additional, Schwarzenberg-Czerny, A., additional, Grant, C. C., additional, Koudelka, O., additional, Lüftinger, T., additional, Rucinski, S. M., additional, Wade, G. A., additional, Alves, J., additional, Guedel, M., additional, Handler, G., additional, Mochnacki, St., additional, Orleanski, P., additional, Pablo, B., additional, Pamyatnykh, A., additional, Ramiaramanantsoa, T., additional, Rowe, J., additional, Whittaker, G., additional, Zawistowski, T., additional, Zocłońska, E., additional, and Zwintz, K., additional

Published
2016
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44. Authors' reply

Author

Wall, C R and Grant, C C

Subjects
Letter
Published
2006

46. Widespread prevalence of a CREBRF variant amongst Māori and Pacific children is associated with weight and height in early childhood

Author

Berry, S D, Walker, C G, Ly, K, Snell, R G, Atatoa Carr, P E, Bandara, D, Mohal, J, Castro, T G, Marks, E J, Morton, S M B, and Grant, C C

Abstract

Objective:Investigating a large and ethnically diverse cohort from the Pacific region, we aimed to replicate and extend the recently reported findings that a CREBRF genetic variant is strongly associated with body mass index in Samoans.Methods:A birth cohort of more than six thousand children was utilised. In this study, genotyping of two markers (rs12513649 and rs373863828) was undertaken in Māori, Pacific, European and Asian individuals in the cohort.Results:We report that these CREBRF genetic variants are not confined to Samoans but are prevalent in all other Pacific populations sampled, including Māori. We found that the rs373863828 variant was significantly associated with growth at 4 years of age. On average, we observed allele-specific increases in weight (P=0·004, +455 g, s.e. 0.158), height (P=0·007, +0·70 cm, s.e. 0.26) and waist circumference (P=0·004, +0·70 cm, s.e. 0.24) at 4 years of age. The rs373863828 variant was not associated with birth weight (P=0·129).Conclusions:We replicated the finding that a CREBRF variant is associated with increased body mass. We then built on the original findings by demonstrating the prevalence of the rs12513649 and rs373863828 variants in multiple Pacific population groups and by demonstrating that the rs373863828 variant is associated with growth in early childhood. Pacific population groups experience a disproportionately high burden of obesity, starting in early childhood. This new knowledge offers potential for evidence-based interventions aimed at establishing healthy growth trajectories from the earliest possible age.

Published
2018
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47. Corticosteroids in sports-related injuries: Friend or Foe.

Author

Rotunno, A., Janse van Rensburg, D. C., Grant, C. C., and Jansen van Rensburg, A.

Subjects
HORMONE therapy, CORTICOSTEROIDS, DOPING in sports, DRUG administration, GLUCOCORTICOIDS, MINERALOCORTICOIDS, SPORTS injuries
Abstract

Corticosteroids act as potent anti-inflammatory drugs and have been used in various sport settings for the treatment of both acute and chronic injuries. Basic physiology and mechanisms of action for gluco- and mineralocorticoids are discussed. Methods of administration, the action on the inflammatory response, and potential short and long-term side effects of corticosteroid use are also deliberated. More specifically, corticosteroid use in the treatment and management of sport-related injuries are discussed, elucidating on the ethical boundaries and anti-doping regulations pertaining to corticosteroid use in sports, as well as putting forth suggestions for the use of local steroid injections and their contraindications. In conclusion, it was found that, despite some controversy in the use of corticosteroid treatment in the sports environment, little empirical evidence exists that could conclusively rule for or against its use. It is however clear that, if clinically justified, there is a significant role for corticosteroid treatment in the realm of sports injury and notably with a relatively low risk profile, if administered correctly. [ABSTRACT FROM AUTHOR]

Published
2017

48. Combining BRITE and ground-based photometry for the β Cephei star v Eridani: impact on photometric pulsation mode identification and detection of several g modes.

Author

Handler, G., Rybicka, M., Popowicz, A., Pigulski, A., Kuschnig, R., Zocłońska, E., Moffat, A. F. J., Weiss, W. W., Grant, C. C., Pablo, H., Whittaker, G. N., Ruciński, S. M., Ramiaramanantsoa, T., Zwintz, K., and Wade, G. A.

Subjects
VV Cephei stars, PHOTOELECTRIC photometry, STELLAR oscillations, CONSTELLATIONS, LIGHT curves
Abstract

We report a simultaneous ground- and space-based photometric study of the β Cephei star v Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit, we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that three dominant pulsation modes of v Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy. [ABSTRACT FROM AUTHOR]

Published
2017
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49. Combining BRITE and ground-based photometry for the β Cephei star ν Eridani: impact on photometric pulsation mode identification and detection of several g modes.

Author

Handler, G., Rybicka, M., Popowicz, A., Pigulski, A., Kuschnig,, R., Zocłońska, E., Moffat, A. F. J., Weiss, W. W., Grant, C. C., Pablo, H., Whittaker, G. N., Ruciński, S. M., Ramiaramanantso, T., Zwintz, K., and Wade, G. A.

Subjects
VV Cephei stars, STELLAR oscillations, CONSTELLATIONS, PHOTOELECTRIC photometry, LIGHT curves
Abstract

We report a simultaneous ground-and space-based photometric study of the β Cephei star ν Eridani. Half a year of observations have been obtained by four of the five satellites constituting BRITE-Constellation, supplemented with ground-based photoelectric photometry. We show that carefully combining the two data sets virtually eliminates the aliasing problem that often hampers time series analyses. We detect 40 periodic signals intrinsic to the star in the light curves. Despite a lower detection limit, we do not recover all the pressure and mixed modes previously reported in the literature, but we newly detect six additional gravity modes. This behaviour is a consequence of temporal changes in the pulsation amplitudes that we also detected for some of the p modes. We point out that the dependence of theoretically predicted pulsation amplitude on wavelength is steeper in visual passbands than those observationally measured, to the extent that three dominant pulsation modes of ν Eridani would be incorrectly identified using data in optical filters only. We discuss possible reasons for this discrepancy. [ABSTRACT FROM AUTHOR]

Published
2017
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50. The use of negative pressure wave treatment in athlete recovery.

Author

van Rensburg, A. Jansen, van Rensburg, D. C. Janse, van Buuren, H. E., Grant, C. C., and Fletcher, L.

Subjects
CREATINE kinase, ATHLETES' health, MUSCLE fatigue, PREVENTION
Abstract

Background: Athletes need to recover fully to maximise performance in competitive sport. Athletes who replenish more quickly and more efficiently are able to train harder and more intensely. Elite athletes subjectively report positive results using lower body negative pressure (LBNP) treatment as an alternate method for rapid recovery, restoring and improving their impaired physical state. Objective data on the efficacy are lacking. Objectives: To investigate the effect of intermittent vacuum therapy on accelerating acute recovery following an athlete's normal daily training schedule of strenuous exercise. Objective measurements of biological markers of muscular fatigue were used to assess recovery. Methods: Twenty-two male cricket players in a randomised cross-over study were divided into a treatment and control group respectively. Following a one-hour high-intensity gym session, the treatment group received three 30-minute LBNP exposure sessions over three consecutive days (0, 24 and 48 hours). Blood lactate and creatine kinase biomarkers were collected to measure the recovery process. After 14 days groups were crossed over and the trial repeated. Results: Heart rate and blood pressure decreased noticeably during treatment, reverting to baseline levels after treatment. Lactate concentrations decreased in both groups after exercise termination; significantly more in the treatment (0.57±0.23 mmol/l) than control group (0.78±0.22 mmol/l), p<0.001). Creatine kinase (CK) was similar in both groups. Athletes' subjective assessments of recovery rated moderately high. Conclusion: LBNP therapy applied as treatment during routine schedule may have a systemic effect in lowering serum lactate levels, but not CK levels. Enhanced recovery of athletes is still unconfirmed. [ABSTRACT FROM AUTHOR]

Published
2017
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