11 research outputs found
Muon anomalous magnetic moment in the standard model with two Higgs doublets
The muon anomalous magnetic moment is investigated in the standard model with
two Higgs doublets (S2HDM) motivated from spontaneous CP violation. Thus all
the effective Yukawa couplings become complex. As a consequence of the non-zero
phase in the couplings, the one loop contribution from the neutral scalar
bosons could be positive and negative relying on the CP phases. The
interference between one and two loop diagrams can be constructive in a large
parameter space of CP-phases. This will result in a significant contribution to
muon anomalous magnetic moment even in the flavor conserving process with a
heavy neutral scalar boson ( 200 GeV) once the effective muon Yukawa
coupling is large (). In general, the one loop contributions
from lepton flavor changing scalar interactions become more important. In
particular, when all contributions are positive in a reasonable parameter space
of CP phases, the recently reported 2.6 sigma experiment vs. theory deviation
can be easily explained even for a heavy scalar boson with a relative small
Yukawa coupling in the S2HDM.Comment: 8 pages, RevTex file, 5 figures, published version Phys. Rev. D 54
(2001) 11501
Build better bones with exercise (B3E pilot trial): results of a feasibility study of a multicenter randomized controlled trial of 12 months of home exercise in older women with vertebral fracture
© 2018, International Osteoporosis Foundation and National Osteoporosis Foundation. Summary: We pilot-tested a trial of home exercise on individuals with osteoporosis and spine fracture. Our target enrollment was met, though it took longer than expected. Participants stayed in the study and completed the exercise program with no safety concerns. Future trials should expand the inclusion criteria and consider other changes. Purpose: Osteoporotic fragility fractures create a substantial human and economic burden. There have been calls for a large randomized controlled trial examining the effect of exercise on fracture incidence. The B3E pilot trial was designed to evaluate the feasibility of a large trial examining the effects of home exercise on individuals at high risk of fracture. Methods: Community-dwelling women = 65 years with radiographically confirmed vertebral compression fractures were recruited at seven sites in Canada and Australia. We randomized participants in a 1:1 ratio to a 12-month home exercise program or equal attention control group, both delivered by a physiotherapist (PT). Participants received six PT home visits in addition to monthly phone calls from the PT and a blinded research assistant. The primary feasibility outcomes of the study were recruitment rate (20 per site in 1 year), retention rate (75% completion), and intervention adherence rate (60% of weeks meeting exercise goals). Secondary outcomes included falls, fractures and adverse events. Results: One hundred forty-one participants were recruited; an average of 20 per site, though most sites took longer than anticipated. Retention and adherence met the criteria for success: 92% of participants completed the study; average adherence was 66%. The intervention group did not differ significantly in the number of falls (IRR 0.97, 95% CI 0.58 to 1.63) or fragility fractures (OR 1.11, 95% CI 0.60 to 2.05) compared to the control group. There were 18 serious adverse events in the intervention group and 12 in the control group. Conclusion: An RCT of home exercise in women with vertebral fractures is feasible but recruitment was a challenge. Suggestions are made for the conduct of future trials
Accelerometry based assessment of gait parameters in children
The objective of this study was to examine if spatio-temporal gait parameters in healthy children can be determined from accelerations measured at the lower trunk as has been demonstrated in adults, previously. Twenty children aged 3-16 years, participated in a protocol that involved repeated walks of different distances in an indoor environment. During walking, accelerations were measured by three orthogonally mounted acceleration sensors in a small wireless device (DynaPort MiniMod) that was attached to the lower back. Based on an inverted pendulum approach, spatio-temporal gait parameters and walking distances were computed from the acceleration signals. Results were compared to video observations and known walking distances and durations. Steps were successfully detected in 99.6+/-0.6% of all observed steps (n=5554). On average, walking distance was accurately estimated (100.6+/-3.3%, range 93-106.7%). No correlation was found between the number of miscounted steps and the total number of steps or the age of the subject. It can be concluded that the use of an inverted pendulum model provides the possibility to estimate spatio-temporal gait parameters in children as well as in adults. The method allows an inexpensive and comfortable assessment of gait parameters in children, is applicable in controlled, indoor environments and could be tested for applicability under free living conditions