2,434 research outputs found
Assessment of the 2,4 km run as a predictor of aerobic capacity
Since the 2,4 km run time test is routinely used in military training programmes as an indicator of aerobic capacity and its possible improvement, an attempt was made to: (i) establish a regression equation of V02max V. 2,4 km run time in a group of 20 young military volunteers; and (ii) determine whether this equation could be used to predict V02max reliably from the 2,4 km time obtained from another group. Before and after training, V02max was measured in all subjects using a treadmill test, and 2,4 km run time was determined in the field. Linear regression equations using the 2,4 km run time as the independent variable accounted for 76 - 92% of the variance in VO2max, while the standard error of the estimate varied from 2,24 - 2,91 ml/kg/min. In the second test group, the directly measured V02max was 59,89 ± 0,99 ml/kg/min, while the mean value estimated from the regression equation of the first group was 59,61 ± 1,16 ml/kg/min (P < 0,001). It was concluded that, in the population studied, the 2,4 km run time in the field reliably predicts V02max measured during treadmill exercise in the laboratory
‘Close enough’ – The link between the Syrian Electronic Army and the Bashar al-Assad regime, and implications for the future development of nation-state cyber counter-insurgency strategies
The case of the Syrian Electronic Army (SEA) offers the chance to study a counter response to the cyber activism of the Arab Spring. Research methods featured an adapted method of snowball sampling. The main technical finding of the study placed the SEA within two degrees of separation from a senior politician within the Assad regime. The core conclusion of the paper is the definition of a ‘close enough’ relationship between the SEA and the Assad regime, defined as distant enough to preserve plausible deniability but close enough to ensure the strategic alignment of the SEA to state policy goals
Assessment of the 2,4 km run as a predictor of aerobic capacity
CITATION: Burger, S.C., Bertram, S.R. & Stewart, R.I. 1990. Assessment of the 2,4 km run as a predictor of aerobic capacity. S Afr Med J, 78(9):327-329.The original publication is available at http://www.samj.org.zaENGLISH ABSTRACT: Since the 2,4 km run time test is routinely used in military training programmes as an indicator of aerobic capacity and its possible improvement, an atemtp was made to: (i) establish a regression equation of VO2(max) v. 2,4 km run time in a group of 20 young military volunteers; and (ii) determine whether this equation could be used to predict VO2(max) reliably from the 2,4 km time obtained from another group. Before and after training, VO2(max) was measured in all subjects using a treadmill test, and 2,4 km run time was determined in the field. Linear regression equations using the 2,4 km run time as the independent variable accounted for 76-92% of the variance in VO2(max), while the standard error of the estimate varied from 2,24-2,91 ml/kg/min. In the second test group, the directly measured VO2(max) was 59,89 ± 0,99 ml/kg/min, while the mean values estimated from the regression equation of the first group was 59,61 ± 1,16 ml/kg/min (P< 0.001). It was concluded that, in the population studied, the 2,4 km run time in the field reliably predicts VO2(max) measured during treadmill exercise in the laboratory.AFRIKAANSE OPSOMMING: Geen opsomming beskikbaarPublisher’s versio
The Effect of Wall Inertia on High-Frequency Instabilities of Flow Through an Elastic-Walled Tube
We examine the effect of wall inertia on the onset of high-frequency self-excited oscillations in flow through an elastic-walled tube. The previous asymptotic model of Whittaker et al. (Proc. Roy. Soc. A466, 2010), for a long-wavelength high-frequency instability in a Starling-resistor set-up, neglected inertia in the tube wall. Here, we extend this model by modifying the ‘tube-law’ for the wall mechanics to include inertial effects. The resulting coupled model for the fluid and solid mechanics is solved to find the normal modes of oscillation for the system, together with their frequencies and growth rates. In the system and parameter regime considered, the addition of wall inertia reduces the oscillation frequency of each mode, however its effect on the stability of the system is not as straightforward. Increasing wall inertia lowers the mean flow rate required for the onset of instability, and is therefore destabilising. However, at higher flow rates the instability growth rate is decreased, and so wall inertia is stabilising here. Overall, the addition of wall inertia decreases the sensitivity of the system to the mean axial flow rate. The theoretical results show good qualitative and reasonable quantitative agreement with direct numerical simulations performed using the oomph-lib framework
Oral flecainide acetate for elimination of ventricular arrhythmias in man
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24476/1/0000751.pd
Radionuclide evaluation of postextrasystolic potentiation of left ventricular function induced by atrial and ventricular stimulation
Postextrasystolic potentiation of left ventricular function induced by ventricular and atrial stimulation was compared in 10 patients using radionuclide ventriculography. After insertion of pacing wires, a preliminary radionuclide ventriculogram was obtained and then ventricular and atrial trigeminy was induced in random order, each with identical R-R coupling intervals, each for 6 to 10 minutes. During the stimulation studies, radionuclide data were acquired in electrocardiographic gated list mode format. Left ventricular ejection fraction and relative end-diastolic and end-systolic volume changes were measured for each reformatted composite sinus, atrial and ventricular premature beat and potentiated beat. The volume changes were normalized to the count-based values obtained for the sinus beat of the appropriate study. Postextrasystolic potentiation induced by either ventricular or atrial stimulation was characterized by similar significant increases in left ventricular ejection fraction (mean +/- standard deviation 7 +/- 3 percent, p < 0.01 versus 7 +/- 5 percent, p < 0.01; difference not significant [NS]) and decreases in relative end-systolic volume (-12 +/- 12 percent, p < 0.01 versus -12 +/- 8 percent, p < 0.01; NS) but little change in relative end-diastolic volume (+5 +/- 10 percent, NS versus +4 +/- 7 percent, NS; NS). This was despite a longer compensatory pause (1,120 +/- 220 versus 1,050 +/- 190 ms, p < 0.01) after the ventricular premature beat. It is concluded that there is no difference in the postextrasystolic potentiation induced by atrial or ventricular premature stimulation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23931/1/0000177.pd
Recommended from our members
Spring 1959
Seed testing - A Service for You by Miss Jessie L. Anderson (page 1) Increased Interest in Two-Year Turf Course by Fred P. Jeffrey - Director of Stockbridge (4) From the Editor (4) Message From Winter School President of 1959 (5) Turf club News (6) Number One Graduate (8) Liquid Fertilization by A.B. Longo (9) Public School Grounds by James Woodhouse (12) Comments on the 1959 Winter School (14) Picture - Stockbridge Turf Majors (16) Picture - Honorary Members of Turf Management Club (17) Letter on Chemical Compatibility (18) The Most Outstanding Turf Senior for 1958 (19) What it Means to be a Turf Manager by R. Russell (20) 10 Steps to a Better Lawn by P. Pedrazzi (24) A Scene to Remember (25) I switched from Hots to Cools by J. Spodnik (26) Why Attend Turfgrass Conferences (27) Picture - Winter School for Turf Managers - 1959 (29) Picture - University of Masssachusetts Annual Turfgrass Conference (30) Organic Fertilizers by O.J. Noer (A-1) Inorganic Fertilizers by Charles Winchell (A-1) Urea Formaldehyde by G.F. Stewart (A-2) Phosphorus and Potash Fertilization by Raph Donaldson (A-3) Questions on Fertilization to the Panel (A-4) Cemetery Maintenance by S.E. Robbins (A-6) Lime by Anson Brewer (A-6) Limited Budgets by R.W. Sharkey (A-7) Fertilization of Park Turf by E.J. Pyle (A-7) Disease and Insect Control by Orlando Capizzi (A-8) Cost of Establishing Turf by Victor Taricano (A-9) Question and Answers (A-10) Control of Pests of Ornamentals and Turf Occuring on Golf Courses by John C. Schread (A-12) Behind the Scenes in Soil Testing and What it Means to You Bertram Gersten and Wm. G. Colby (A-19) Lessons Learned from the 1958 Season as Applied to Golf Course Maintenance by A.M. Radko (A-21) The Outlook in Chemical Weed Control on Fine Turf by John Gallagher (A-24) New Developments in Turfgrass Disease Diagnosis and Control by Frank Howard (A-26
Better post-operative prediction and management of chronic pain in adults after total knee replacement:the multidisciplinary STAR research programme including RCT
Background: The treatment of osteoarthritis with knee replacement aims to reduce pain and disability.
However, some people experience chronic pain.
Objectives: To improve outcomes for people with chronic pain after knee replacement by identifying
post-surgical predictors and effective interventions, characterising patient pathways and resource use,
developing and evaluating a new care pathway, and exploring non-use of services.
Design: The programme comprised systematic reviews, national database analyses, a cohort study,
intervention development, a randomised controlled trial, health economic analyses, qualitative studies
and stakeholder engagement. Extensive and meaningful patient and public involvement underpinned all
studies.
Setting: NHS, secondary care, primary care.
Participants: People with, or at risk of, chronic pain after knee replacement and health-care
professionals involved in the care of people with pain.
Interventions: A care pathway for the management of people with pain at 3 months after knee
replacement.
Main outcome measures: Patient-reported outcomes and cost-effectiveness over 12 months.
Data sources: Literature databases, the National Joint Registry, Hospital Episode Statistics, patient-
reported outcomes, the Clinical Practice Research Datalink, the Clinical Outcomes in Arthroplasty Study,
the Support and Treatment After joint Replacement randomised trial, interviews with 90 patients and 14
health-care professionals, and stakeholder events.
Review methods: Systematic reviews of cohort studies or randomised trials, using meta-analysis or
narrative synthesis.
Results: In the Clinical Outcomes in Arthroplasty Study cohort, 14% of people experienced chronic pain 1
year after knee replacement. By 5 years, 65% reported no pain, 31% fluctuated and 4% remained in chronic
pain. People with chronic pain had a worse quality of life, higher primary care costs, and more frequent
analgesia prescriptions, particularly for opioids, than those not in chronic pain. People with chronic pain after
knee replacement who made little or no use of services often felt nothing more could be done, or that further
treatments may have no benefit or cause harm. People described a feeling of disconnection from their
replaced knee. Analysis of UK databases identified risk factors for chronic pain after knee replacement. Pre-
operative predictors were mild knee pain, smoking, deprivation, body mass index between 35 and 40 kg/m2
and knee arthroscopy. Peri- and post-operative predictors were mechanical complications, infection,
readmission, revision, extended hospital stay, manipulation under anaesthetic and use of opioids or
antidepressants. In systematic reviews, pre-operative exercise and education showed no benefit in relation
to chronic pain. Peri-operative interventions that merit further research were identified. Common peri-
operative treatments were not associated with chronic pain. There was no strong evidence favouring specific
post-operative physiotherapy content. We evaluated the Support and Treatment After joint Replacement
care pathway in a multicentre randomised controlled trial. We randomised 363 people with pain at 3 months
after knee replacement from eight NHS Trusts in England and Wales. At 12 months’ follow-up, the
intervention group had lower mean pain severity (adjusted difference –0.65, 95% confidence interval –1.17
to -0.13; p = 0.014) and pain interference (adjusted difference –0.68, 95% confidence interval –1.29 to -0.08;
p = 0.026), as measured on the Brief Pain Inventory subscales (scale 0–10). People receiving the Support and
Treatment After joint Replacement pathway had lower NHS and Personal Social Services costs (–£724, 95%
confidence interval –£150 to £51) and higher quality-adjusted life-years (0.03, 95% confidence interval
–0.008 to 0.06) than those with usual care. The Support and Treatment After joint Replacement pathway
was cost-effective with an incremental net monetary benefit at the £20,000 per quality-adjusted life-year
threshold of £1256 (95% confidence interval £164 to £2348), indicating a 98.79% probability that the
intervention is the cost-effective option. Participants found the Support and Treatment After joint
Replacement pathway acceptable, with opportunities to receive information and discuss concerns while
ensuring further treatment and support. In systematic reviews considering treatments for chronic pain after
surgery we identified some unifactorial interventions that merit further research after knee replacement.
Health-care professionals delivering and implementing the Support and Treatment After joint Replacement
pathway valued its focus on neuropathic pain and psychosocial issues, enhanced patient care, formalised
referrals, and improved pain management. Stakeholders supported pathway implementation.
Limitations: Database analyses were limited to factors recorded in data sets. Pain was only measured 6
months after surgery. However, analyses including large numbers of centres and patients should be
generalisable across the NHS. In many studies found in systematic reviews, long-term pain was not a key
outcome.
Conclusions: The Support and Treatment After joint Replacement pathway is a clinically effective and
cost-effective, acceptable intervention for the management of chronic pain after knee replacement.
Unifactorial interventions merit further study before inclusion in patient care. People with pain should
be empowered to seek health care, with the support of health-care professionals.
Future work: Future work should include research relating to the implementation of the Support and
Treatment After joint Replacement pathway into the NHS, an assessment of its long-term clinical
effectiveness and cost-effectiveness and wider application, and an evaluation of new interventions for
incorporation in the pathway. It will also be important to design and conduct research to improve
communication between patients and health-care professionals before surgery; explore whether or not
education and support can enable earlier recognition of chronic pain; consider research that may identify
how to support people’s feelings of disconnectedness from their new knee; and design and evaluate a
pre-surgical intervention based on risk factors.
Study registration: All systematic reviews were registered on PROSPERO (CRD42015015957,
CRD42016041374 and CRD42017041382). The Support and Treatment After joint Replacement
randomised trial was registered as ISRCTN92545361.
Funding: This project was funded by the National Institute for Health and Care Research (NIHR)
Programme Grants for Applied Research programme and will be published in full in Programme Grants for
Applied Research; Vol. 11, No. 3. See the NIHR Journals Library website for further project information
A comprehensive 1000 Genomes-based genome-wide association meta-analysis of coronary artery disease
Existing knowledge of genetic variants affecting risk of coronary artery disease (CAD) is largely based on genome-wide association studies (GWAS) analysis of common SNPs. Leveraging phased haplotypes from the 1000 Genomes Project, we report a GWAS meta-analysis of 185 thousand CAD cases and controls, interrogating 6.7 million common (MAF>0.05) as well as 2.7 million low frequency (0.005<MAF<0.05) variants. In addition to confirmation of most known CAD loci, we identified 10 novel loci, eight additive and two recessive, that contain candidate genes that newly implicate biological processes in vessel walls. We observed intra-locus allelic heterogeneity but little evidence of low frequency variants with larger effects and no evidence of synthetic association. Our analysis provides a comprehensive survey of the fine genetic architecture of CAD showing that genetic susceptibility to this common disease is largely determined by common SNPs of small effect siz
- …