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The hollow-fibre oxygenator is a key component of any extracorporeal circuit used to provide cardiopulmonary bypass (CPB) during open-heart surgery. Since the oxygenator is placed downstream of the pump, the energy losses over it have a direct impact on the quality of pulsatile pressure and flow waveforms. The objective of this study was to describe the effects of hydrodynamic characteristics of the oxygenator on energy transfer during pulsatile, normothermic CPB. Twenty-three adult patients scheduled for coronary bypass surgery were divided randomly into two groups, using either an oxygenator (Group 1) with a relatively high-resistance and low-compliance (2079 ± 148 dyn.s.cm-5 and 0.00348 ± 0.00071 ml.mmHg-1, respectively) or an oxygenator (Group 2) with a relatively low-resistance and high-compliance (884 ± 464 dyn.s.cm-5 and 0.01325 ± 0.00161 ml .mmHg-1, respectively). During perfusion, pre- and post-oxygenator pressures, radial artery pressure, and blood flow were recorded simultaneously. A 32% decline of mean pressure was observed in Group 1 and a 16% decline in Group 2 (p<0.0001). Another decrease by approximately 73% in mean pressure in the rest of the perfusion system was noted in both groups. The mean radial artery pressure did not differ between the groups (74 ± 6 mmHg in Group 1 and 73 ± 6 mmHg in Group 2, p=0.608). Although lower total energy transfer indices were noticed through the low-resistance oxygenator (Group 2), both oxygenators showed a decrease of the generated pump oscillatory energy of approximately 50%. Despite the differences in resistance and compliance of the hollow-fibre oxygenators used, both oxygenators cause a comparable loss of generated oscillatory energy. Exclusion of the oxygenator downstream of the pulsatile pump would improve energy transfer during CPB.

VESPA, Vibrational Excitation Spectrometer with Pyrolytic-graphite Analysers, aims to probe molecular excitations via inelastic neutron scattering. It is a thermal high resolution inverted geometry time-of-flight instrument designed to maximise the use of the long pulse of the European Spallation Source. The wavelength frame multiplication technique was applied to provide simultaneously a broad dynamic range (about 0-500 meV) while a system of optical blind choppers allows to trade flux for energy resolution. Thanks to its high flux, VESPA will allow the investigation of dynamical and in situ experiments in physical chemistry. Here we describe the design parameters and the corresponding McStas simulations.

Background: Fatigue is a frequently reported and disabling symptom in multiple sclerosis (MS). Objective: To investigate the effectiveness of an individual energy conservation management (ECM) intervention on fatigue and participation in persons with primary MS-related fatigue. Methods: A total of 86 severely fatigued and ambulatory adults with a definite diagnosis of MS were randomized in a single-blind, two-parallel-arm randomized clinical trial to the ECM group or the information-only control group in outpatient rehabilitation departments. Blinded assessments were carried out at baseline and at 8, 16, 26 and 52 weeks after randomization. Primary outcomes were fatigue (fatigue subscale of Checklist Individual Strength – CIS20r) and participation (Impact on Participation and Autonomy scale – IPA). Results: Modified intention-to-treat analysis was based on 76 randomized patients (ECM, n = 36; MS nurse, n=40). No significant ECM effects were found for fatigue (overall difference CIS20r between the groups = −0.81; 95% confidence interval (CI), −3.71 to 2.11) or for four out of five IPA domains. An overall unfavourable effect was found in the ECM group for the IPA domain social relations (difference between the groups = 0.19; 95% CI, 0.03 to 0.35). Conclusion: The individual ECM format used in this study did not reduce MS-related fatigue and restrictions in participation more than an information-only control condition.

Remote environmental monitoring systems require effective energy management to allow reliable long-term operation without frequent maintenance to replace or recharge batteries. To design and analyze relevant energy management strategies, we have developed Simulink-based models of a recently constructed monitoring device to evaluate its potential performance. The model uses long-term solar energy data from two locations, Chamela, Mexico, and Fairview, Canada, to estimate the energy harvesting capabilities of the device. Using the simulator, we have developed and evaluated a fuzzy energy management strategy that determines how the device should operate to match the solar energy profile in each location. Solar energy in Chamela, Mexico is abundant and consistent so an energy harvesting remote monitoring device could have a high activity level without risking device failure. Fairview, Canada, has limited solar resources in the winter but plenty in the summer; a device dependent upon this energy source must adapt its activity level to match energy availability or risk running out of energy. While the simulated device in Mexico outperforms the one in Canada, both succeed in matching the available environmental resources and largely avoid energy related device failure. In the future, their performance can be improved by optimizing the designed strategies and further improving the details of the simulation.

The aim of this study was to examine whether impaired balance control is partly responsible for the increased energy cost of walking in persons with a lower limb amputation (LLA). Previous studies used external lateral stabilization to evaluate the energy cost for balance control; this caused a decrease in energy cost, with concomitant decreases in mean and variability of step width. Using a similar set-up, we expected larger decreases for LLA than able-bodied controls. Fifteen transtibial amputees (TT), 12 transfemoral amputees (TF), and 15 able-bodied controls (CO) walked with and without external lateral stabilization provided via spring like cords attached to the waist. Effects of this manipulation on energy cost, step parameters, and pelvic motion were evaluated between groups. TT (-5%) and CO (-3%) showed on average a small reduction in energy cost when walking with stabilization, whereas TF exhibited an increase in energy cost (+6.5%) The difference in the effect of stabilization was only significant between TT and TF. Step width, step width variability, and medio-lateral pelvic displacement decreased significantly with stabilization in all groups, especially in TT. Contrary to expectations, external lateral stabilization did not result in a larger decrease in the energy cost of walking for LLA compared to able-bodied controls, suggesting that balance control is not a major factor in the increased cost of walking in LLA. Alternatively, the increased energy cost with stabilization for TF suggests that restraining (medio-lateral) pelvic motion impeded necessary movement adaptations in LLA, and thus negated the postulated beneficial effects of stabilization on the energy cost of walking.

This cross-sectional study into children and young adults with cerebral palsy (CP) aimed to assess the association of gross energy cost (EC), net EC and net nondimensional (NN) EC during walking with age and body height, compared to typically developing (TD) peers.Data was collected in 128 participants with CP (mean age 11y9mo; GMFCS I,n=48; II,n=56; III, n=24) and in 63 TD peers (mean age 12y5mo). Energy cost was assessed by measuring the oxygen consumption during over-ground walking at comfortable speed. Outcome measures derived from the assessment included the gross and net EC, and NN EC. Differences between the groups in the association between gross, net and NN EC with age and body height, were investigated with regression analyses and interaction effects (p<0.05).Interaction effects for age and body height by group were not significant, indicating similar associations for gross, net and NN EC with age or body height among groups. The models showed a significant decline for gross, net and NN EC with increasing age per year (respectively -0.201Jkg-1m-1; -0.073Jkg-1m-1; -0.007) and body height per cm (respectively -0.057Jkg-1m-1; -0.021Jkg-1m-1; -0.002).Despite higher gross and net EC values for CP compared to TD participants , similar declines in EC outcomes can be expected with growth for participants aged 4-22 years with CP. All energy cost outcomes showed a decline with growth, indicating that correcting for this decline is required when evaluating changes in gross EC, and, to a lesser extent, in net and NN EC in response to treatment or from natural course over time.