The Reproducibility of Berg Balance Scale and the Single-Leg Stance in Chronic Stroke and the Relationship Between the Two Tests.

OBJECTIVE: To assess the reproducibility of the Berg Balance Scale (BBS) and the Single-leg Stance (SLS), and the validity of the SLS as an independent test of upright postural control in patients with chronic stroke. DESIGN: An intra-rater test-retest reproducibility study. The BBS and the SLS were assessed twice, 7 days apart. SETTING: A university hospital. PARTICIPANTS: Fifty individuals; 6-46 months after a stroke. MAIN OUTCOME MEASUREMENTS: The reproducibility of the BBS and the SLS was evaluated with intraclass correlation coefficient (ICC(2,1)), the mean difference between the 2 test sessions (d̄) with 95% confidence interval (95% CI), the standard error of measurement (standard error of measurement [SEM]%), the smallest real difference (SRD%), and the Bland-Altman graphs. To assess validity of SLS, the relationship between the SLS and the BBS was analyzed by the Pearson correlation coefficient. RESULTS: The ICC(2,1) was 0.88 for the BBS, and the ICC(2,1) values were 0.88 for the nonparetic limb and 0.92 for the paretic lower limb for the SLS. The smallest change that indicates a real improvement for a group of individuals, SEM%, was 3% for BBS, 15% for the nonparetic limb and 27% for the paretic limb for SLS. The smallest real difference for a single individual was 8% for BBS but was higher for SLS, at 42% for the nonparetic limb, and 74% for the paretic limb. There was a significant relationship between the SLS and the BBS (r = 0.65-0.79; P < .001). CONCLUSIONS: The BBS and the SLS are reproducible measurements in patients with chronic stroke, but only the BBS is sensitive enough to follow changes over time or after an intervention. The SLS is strongly related to the BBS and can be used as an independent test to measure upright postural control after a stroke

Long-term benefits of progressive resistance training in chronic stroke: A 4-year follow-up.

OBJECTIVES: To evaluate the long-term benefits of progressive resistance training in chronic stroke. DESIGN: A 4-year follow-up of a randomized controlled trial of progressive resistance training. SUBJECTS: Eighteen women and men (mean age 66 (standard deviation 4) from the original group of 24 post-stroke participants. METHODS: The training group (n = 11) had participated in supervised progressive resistance training of the knee extensors and flexors (80% of maximum) twice weekly for 10 weeks, whereas the control group (n = 7) had continued their usual daily activities. Muscle strength was evaluated isotonically and isokinetically (60º/s; Biodex), muscle tone with the Modified Ashworth Scale, gait performance by the Timed Up and Go test, the Fast Gait Speed test and 6-Minute Walk test, and perceived participation with the Stroke Impact Scale (Participation domain). RESULTS: Four years after the intervention, the improvements in muscle strength in the training group were maintained, and there was no reduction in strength in the control group. Compared with baseline there were still significant between-group differences for both isotonic and isokinetic strength. No significant between-group differences were found in muscle tone, gait performance or perceived participation. CONCLUSION: The results indicate that there is a long-term benefit of progressive resistance training in chronic stroke. This implies that progressive resistance training could be an effective training method to improve and maintain muscle strength in a long-term perspective

Experimental study of time-dependent properties of a low-pH concrete for deposition tunnels

The Swedish Nuclear Fuel and Waste Management Company developed a method for the final disposal of canisters for spent nuclear fuel in tunnels at depths of about 500 meters. The concept for closure of the deposition tunnels is based on a bentonite seal supported by a spherical concrete dome structure. In order to fulfil the requirements specific to the repository concept, a special mix of low-pH self-compacting concrete was developed. A series of large-scale castings and laboratory tests were conducted to gain experience on this low-pH concrete mix, in conjunction with the full-scale demonstration test of an unreinforced concrete dome plug in the underground hard rock laboratory in \uc4sp\uf6, Sweden. The laboratory tests aimed at studying the creep properties under high sustained compressive stresses of the low-pH concrete mix, its shrinkage properties and the properties of the rock-concrete interface. This paper provides an overview of these tests and analyses the latest results of the recently completed creep tests, which include 6 years of measurements. These results allow to improve understanding of the structural behaviour of the concrete plug and to assess the effects of the very high pressure acting on the plug on its deformations, cracking and water tightness

Experimental study of time-dependent properties of a low-pH concrete for deposition tunnels

The Swedish Nuclear Fuel and Waste Management Company developed a method for the final disposal of canisters for spent nuclear fuel in tunnels at depths of about 500 meters. The concept for closure of the deposition tunnels is based on a bentonite seal supported by a spherical concrete dome structure. In order to fulfil the requirements specific to the repository concept, a special mix of low-pH self-compacting concrete was developed. A series of large-scale castings and laboratory tests were conducted to gain experience on this low-pH concrete mix, in conjunction with the full-scale demonstration test of an unreinforced concrete dome plug in the underground hard rock laboratory in \uc4sp\uf6, Sweden. The laboratory tests aimed at studying the creep properties under high sustained compressive stresses of the low-pH concrete mix, its shrinkage properties and the properties of the rock-concrete interface. This paper provides an overview of these tests and analyses the latest results of the recently completed creep tests, which include 6 years of measurements. These results allow to improve understanding of the structural behaviour of the concrete plug and to assess the effects of the very high pressure acting on the plug on its deformations, cracking and water tightness

Analysis of tensile behavior of recycled aggregate concrete using acoustic emission technique

Recycled concrete aggregate (RCA) was processed from reinforced concrete edge beams sourced from a demolished bridge in Sweden. This material replaced different ratios of coarse aggregate in a benchmark concrete. The tensile behavior of the developed concrete mixes was characterized via monotonic and cyclic uniaxial tensile tests performed on notched cylinders. Such tensile tests allow for the quantification of the fracture energy and softening behavior of the concrete. Moreover, acoustic emission (AE) measurements were conducted in conjunction with the cyclic tests to characterize e.g. micro‐crack initiation and development, as well as crack localization. The tensile behavior of the various materials was found to be similar with minimal variation in the results. However, the softening behavior suggests that the RCA materials are slightly more brittle compared to both the mother and benchmark materials, which could be indicative of differences in the interface transition zones. The corresponding AE measurements also indicated similarities between the micro‐crack initiation and development for these mixes. It can be constituted that if the concrete used to produce RCA is of high quality and from one source, the resulting RAC will have adequate tensile properties with minimal variation, despite the aggregate replacement ratio

Physical Activity and the Association With Self-Reported Impairments, Walking Limitations, Fear of Falling and Incidence of Falls in Persons With Late Effects of Polio.

The purpose of this study was to determine the association between physical activity and self-reported disability in ambulatory persons with mild to moderate late effects of polio (N=81, mean age 67 years). The outcome measures were: Physical Activity and Disability Survey (PADS), a pedometer, Self-reported Impairments in Persons with Late Effects of Polio Scale (SIPP), Walking Impact Scale (Walk-12), Falls Efficacy Scale - International (FES-I) and self-reported incidence of falls. The participants were physically active on average 158 minutes per day and walked 6212 steps daily. Significant associations were found between PADS and Walk-12 (r = -0.31, p < 0.001), and between the number of steps and SIPP, Walk-12 and FES-I (r = -0.22 to -0.32, p < 0.05). Walk-12 and age explained 14% of the variance in PADS and FES-I explained 9% of the variance in number of steps per day. Thus, physical activity was only weakly to moderately associated with self-reported disability

Anchorage capacity of corroded smooth reinforcement bars in existing reinforced structures.

Concrete structures are strongly affected by reinforcement corrosion, the most common cause of deterioration.Most studies on structural effects of corrosion rely on artificial methods to obtain a corrosionlevel that would otherwise require years, but doubts on the soundness of the methods have been raised.Specimens taken from existing structures offer the chance of studying the effect of natural corrosion,however the choice of the test setup is challenging. Hence, pilot tests are carried out to investigate theoptimal design for testing the anchorage capacity of specimens with smooth reinforcements. The outcomeis an asymmetrically supported 3-point bending beam test. The benefits of using complementarytools as Digital Image Correlation (DIC), Non-Linear Finite Element Analysis (NLFEA), pull-out testsand tensile tests and 3D scanning of the bars are presented