216 research outputs found
The prevalence of work-related musculoskeletal disorders in long-distance bus drivers
Background: Work-related musculoskeletal disorders (WRMSDs) contribute to poor posture and prolonged stress and strain due to work demands and the environment.Objective: The objective of the study was to determine the prevalence of WRMSDs in long-distance bus drivers.Methods: A cross-sectional survey study was conducted to determine the prevalence of WRMSDs among male long-distance bus drivers. Eighty-nine participants were selected from a reputable bus company in Pretoria to participate in the study. The Nordic Musculoskeletal Questionnaire (NMQ) was used to determine self-reported WRMSDs.Results: The average age of the participants was 45 years, with a mean height and weight of 1.69 m and 85.4 kg respectively. Participants in the study had a mean body mass index of 29.9 kg.m-2, categorising them as overweight. From the bus drivers who reported WRMSDs due to driving (22%), most of the pain was noted in the upper back (44%), followed by lower back (42%), neck (42%), shoulder (37%), and wrist/hand (31%). A strong, positive association existed between ankle and knee pain using Kendall’s tau-b correlation (τb = .71, p = .0001). A moderate and positive association was further noted between pain in the neck/shoulder (τb = .59, p = .0001) and upper back/shoulder (τb = .59, p = .0001).Conclusion: The greatest proportion of pain was experienced along the axial skeleton in long-distance bus drivers. Upper back pain was the most prevalent of the WRMSDs reported in these drivers.Keywords: maladroit postures; musculoskeletal pain; kinetic chain; axial skeleton; appendicular skeleto
Second T = 3/2 state in B and the isobaric multiplet mass equation
Recent high-precision mass measurements and shell model calculations~[Phys.
Rev. Lett. {\bf 108}, 212501 (2012)] have challenged a longstanding explanation
for the requirement of a cubic isobaric multiplet mass equation for the lowest
isospin quartet. The conclusions relied upon the choice of the
excitation energy for the second state in B, which had two
conflicting measurements prior to this work. We remeasured the energy of the
state using the reaction and significantly disagree
with the most recent measurement. Our result supports the contention that
continuum coupling in the most proton-rich member of the quartet is not the
predominant reason for the large cubic term required for nuclei
Changes in neutrophil count, creatine kinases and muscle soreness after repeated bouts of downhill running
Objective. A primary objective was to examine circulating neutrophil count after repeated bouts of downhill running. An additional aim was to determine creatine kinase (CK)
levels during the initial 12 hours, after repeated DHRs.
Design. Eleven healthy, untrained Caucasian males performed 2 x 60 min bouts of DHR (-13.5%), spaced 14 days
apart, at a speed equal to 75% VO2max on a level grade. Blood was collected before, after, and every hour for 12 hours, and every 24 hours for 6 days. Absolute neutrophil
count, CK, and delayed-onset muscle soreness (DOMS) were assessed. Results were analysed using repeated measures ANOVA (
The effects of an L-methionine combination supplement on symptoms of upper respiratory tract infections and performance in ultramarathon runners before, during and after ultra-endurance exercise
Objective. To evaluate whether supplementation with an L-methionine combination would reduce the incidence of upper respiratory tract symptoms (URTS) and improve performance in ultramarathon runners.
Design. A double-blind placebo-controlled study.
Setting. Twenty-one ultramarathon runners (17 males, 4 females) preparing for participation in an 87.3 km ultramarathon.
Interventions. L-methionine combination supplement (L-methionine, vitamin B6, vitamin B12, folic acid and magnesium) or placebo containing potato starch.
Main outcome measures. Incidence of URTS was recorded during the runner's preparation for an ultramarathon race (75 days) and recovery from the same (75 days). CD4+, CD8+ cell counts and ratios were measured pre race, immediately post race and 75 days post race. VO2max and endurance fitness (percentage VO2max at 4 mmol-1 lactate concentration) were measured during the preparation for the race.
Results. During the preparation period the incidence of URTS was 36% in the supplement group and 80% in the placebo group (p = 0.08). The incidence of URTS during the 3 weeks post race was 27% in the supplement group and 40% in the placebo group (p = 0.65). The CD4+/CD8+ cell ratios were not significantly different between groups. Endurance fitness prior to the race and race times were not significantly different.
Conclusions. Although the findings of the current study show that an L-methionine combination supplement did not reduce the incidence of URTS or improve performance in ultramarathon runners, benefits may be found with a more detailed investigation using larger sample sizes and immunosuppressed athletes.
South African Journal of Sports Medicine Vol.16(1) 2004: 10-1
Search for highly excited states in 28Si
The theoretical and experimental determination of superdeformed states in nuclei in the mass region A≤40 has been since a long time one of the major challenges of nuclear structure studies. Despite the considerable experimental and theoretical work dedicated to this topic, up to now superdeformed bands have been found in only two nuclei, 36Ar and 40Ca. While the experimental signature of the superdeformed nature of those states is irrefutable, their theoretical interpretation is still uncertain. In particular, it is not clear whether clusterisation is responsible of the onset of superdeformation. For this reason, we wanted to investigate an even lighter system, 28Si, where a number of theoretical calculations predict the presence of superdeformation as an effect of the cluster structure of the nucleus
Dipole polarizability of 120Sn and nuclear energy density functionals
The electric dipole strength distribution in 120Sn between 5 and 22 MeV has
been determined at RCNP Osaka from a polarization transfer analysis of proton
inelastic scattering at E_0 = 295 MeV and forward angles including 0{\deg}.
Combined with photoabsorption data an electric dipole polarizability
\alpha_D(120Sn) = 8.93(36) fm^3 is extracted. The dipole polarizability as
isovector observable par excellence carries direct information on the nuclear
symmetry energy and its density dependence. The correlation of the new value
with the well established \alpha_D(208Pb) serves as a test of its prediction by
nuclear energy density functionals (EDFs). Models based on modern Skyrme
interactions describe the data fairly well while most calculations based on
relativistic Hamiltonians cannot.Comment: 6 pages, 4 figure
Low-energy electric dipole response in 120Sn
The electric dipole strength in 120Sn has been extracted from proton
inelastic scattering experiments at E_p = 295 MeV and at forward angles
including 0 degree. Below neutron threshoild it differs from the results of a
120Sn(gamma,gamma') experiment and peaks at an excitation energy of 8.3 MeV.
The total strength corresponds to 2.3(2)% of the energy-weighted sum rule and
is more than three times larger than what is observed with the (gamma,gamma')
reaction. This implies a strong fragmentation of the E1 strength and/or small
ground state branching ratios of the excited 1- states.Comment: 7 pages, 6 figure
Pygmy dipole resonance in 208Pb
Scattering of protons of several hundred MeV is a promising new spectroscopic
tool for the study of electric dipole strength in nuclei. A case study of 208Pb
shows that at very forward angles J^pi = 1- states are strongly populated via
Coulomb excitation. A separation from nuclear excitation of other modes is
achieved by a multipole decomposition analysis of the experimental cross
sections based on theoretical angular distributions calculated within the
quasiparticle-phonon model. The B(E1) transition strength distribution is
extracted for excitation energies up to 9 MeV, i.e., in the region of the
so-called pygmy dipole resonance (PDR). The Coulomb-nuclear interference shows
sensitivity to the underlying structure of the E1 transitions, which allows for
the first time an experimental extraction of the electromagnetic transition
strength and the energy centroid of the PDR.Comment: submitted to Phys. Rev.
Changes in neutrophil count, creatine kinases and muscle soreness after repeated bouts of downhill running
Objective. A primary objective was to examine circulating neutrophil count after repeated bouts of downhill running. An additional aim was to determine creatine kinase (CK)
levels during the initial 12 hours, after repeated DHRs.
Design. Eleven healthy, untrained Caucasian males performed 2 x 60 min bouts of DHR (-13.5%), spaced 14 days
apart, at a speed equal to 75% VO2max on a level grade. Blood was collected before, after, and every hour for 12 hours, and every 24 hours for 6 days. Absolute neutrophil
count, CK, and delayed-onset muscle soreness (DOMS) were assessed. Results were analysed using repeated measures ANOVA (
Changes in neutrophil count, creatine kinases and muscle soreness after repeated bouts of downhill running
Objective. A primary objective was to examine circulating neutrophil count after repeated bouts of downhill running. An additional aim was to determine creatine kinase (CK)
levels during the initial 12 hours, after repeated DHRs.
Design. Eleven healthy, untrained Caucasian males performed 2 x 60 min bouts of DHR (-13.5%), spaced 14 days
apart, at a speed equal to 75% VO2max on a level grade. Blood was collected before, after, and every hour for 12 hours, and every 24 hours for 6 days. Absolute neutrophil
count, CK, and delayed-onset muscle soreness (DOMS) were assessed. Results were analysed using repeated measures ANOVA (
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