Background. The purpose of this efficacy study was to measure the dose–response effect of a free weight-based resistance training program by comparing the effects of two training intensities ...(low-moderate and high) of the knee extensor (KE) muscles on muscle function, functional limitations, and self-reported disability. Methods. The authors conducted a single-blinded, randomized, placebo-controlled trial. Twenty-two institutionalized elders (mean age, 81.5 years) were assigned to either high-intensity strength training (HI; n = 8), low-moderate intensity strength training (LI; n = 6), or weight-free placebo-control training (PC; n = 8). The HI group trained at 80% of their 1-repetition maximum and the LI group trained at 40%. All groups performed 3 sets of 8 repetitions, 3 times per week for 10 weeks. Outcome measures included KE maximal strength, KE endurance, and functional performance as assessed by 6-minute walking, chair-rising, and stair-climbing tests, and by self-reported disability. Results. KE strength and endurance, stair-climbing power, and chair-rising time improved significantly in the HI and LI groups compared with the PC group. Six-minute walking distance improved significantly in the HI group but not in the LI group compared with the PC group. Changes observed in HI were significantly different from those observed in the LI group for KE strength and endurance and the 6-minute walking test, with a trend in the same direction for chair-rising and stair-climbing. Changes in strength were significantly related to changes in functional outcomes, explaining 37% to 61% of the variance. Conclusions. These results show strong dose–response relationships between resistance training intensity and strength gains, and between strength gains and functional improvements after resistance training. Low-moderate intensity resistance training of the KE muscles may not be sufficiently robust from a physiologic perspective to achieve optimal improvement of functional performance. Supervised HI, free weight-based training for frail elders appears to be as safe as lower intensity training but is more effective physiologically and functionally.
Abstract Background The introduction of endoscopic techniques has led to debate about optimal management of early oesophageal adenocarcinoma. The aim was to evaluate patient selection and outcomes ...for endoscopic or surgical treatment at a tertiary referral centre. Methods A prospectively collected database of consecutive patients staged with high-grade dysplasia (HGD) or T1 oesophageal adenocarcinoma treated with curative intent between 2005 and 2013 was undertaken. All patients were discussed at the multidisciplinary team meeting. Surgical treatment was by thoracoscopic assisted or standard/laparoscopic assisted Ivor Lewis oesophagectomy. Endoscopic treatment was a structured programme of endoscopic mucosal resection (EMR) and/or radiofrequency ablation (RFA). Outcomes included treatment variables, recurrence and complications. Results 83 patients treated; 50 with endoscopic therapy (EMR only-4, EMR then RFA-22, RFA only-24) and 38 by surgery (33 straight to surgery and 5 following EMR). Median age (67) and mean follow-up (21 months) were similar. HGD was more common in the endoscopic group (32/50, 64%, vs.3/33, 9%, p = 0.0001). Significant complications were more common following surgery (13/38, 34%, vs. 1/50, 2%, p = 0.0001). There were two in-hospital deaths following oesophagectomy (1 open, 1 thoracoscopic). Endoscopic treatment beyond 12 months for persisting HGD/intramucosal disease was required in 2 patients. Recurrence of HGD/invasive cancer was diagnosed in 2/36 (5.6%, T1a recurrence) of endoscopic and 1/38 (2.6%, T2N0 - subsequent hepatic metastases) surgical patients. Conclusion A management algorithm including both endoscopic treatment and oesophagectomy provides optimal outcome for these patients. Due to additional morbidity of surgery, endoscopic treatment is appropriate first-line treatment.
The 4π neutron detector CARMEN Ledoux, X.; Laborie, J.-M.; Pras, P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2017, Letnik:
844
Journal Article
Recenzirano
CARMEN is a 4π neutron detector filled with a gadolinium-loaded liquid scintillator built to measure neutron multiplicity distributions. It is used to study fission and (n,xn) reactions. In addition ...to neutron multiplicity measurements, CARMEN can be used to measure neutron energy spectra with the time-of-flight technique, thanks to the time properties of the prompt signal. The detector, detection technique and efficiency determination are presented in detail. Two examples are also presented: the measurement of 252Cf spontaneous fission neutron multiplicity probability distribution and the measurement of the neutron energy spectrum emitted by an Am-Be radioactive source.
The “lead-slowing-down-spectrometer” method is an established technique for measuring neutron-induced reaction cross-sections. It is known to provide high neutron fluences below
100
keV
. In this ...work, the possibility of applying this method to the measurement of the neutron-induced fission cross-section of shortlived actinides and in particular of the
77
eV
isomer of
235
U
is investigated. Numerical simulations and a test-experiment using a photovaltaic cell fission detector demonstrate the feasibility of such a measurement at the Los Alamos Neutron Science Center using
800
MeV
proton-induced spallation to provide source neutrons.
Spallation neutron production in proton induced reactions on Pb targets at 0.8, 1.2, and 1.6 GeV has been measured at the SATURNE accelerator. Double-differential cross sections were obtained over a ...broad angular range from which averaged neutron multipli
Based on a detailed analysis of the external appearance of redpoll Acanthis skins, Knox (1993) explicitly accused the collector Richard Meinertzhagen of having stolen specimens from the Natural ...History Museum bird skin collection and re-labelling them. Here, I test Knox's results using independent evidence of the internal appearance of the specimens in question derived from radiography. Radiographic evidence strongly supported Knox's overall conclusion of fraud by Meinertzhagen but revealed limitations inherent in his attempt to determine the collection history of bird skins using external appearance alone. Although results in such investigations are inherently likely to be probabilistic rather than certain, a multi-factorial approach, taking a wide array of evidence into account, is most likely to engender confidence in the outcome.
Experiments performed at Lab. Nat. SATURNE on neutron produced by spallation from proton beams in the range 0.8 - 1.6 GeV are presented. Experimental data compared with codes show a significant ...improvement of the recent intra-nuclear cascade (J. Cugnon). This is also true in the same way for the neutron production from thick targets. However the model underestimates the energetic neutrons produced in the backward direction and other quantities as residual nuclei cross sections are not accurately predicted.