Chinese translation and validation of the Oxford Knee Scale for patients with knee osteoarthritis

Background: Oxford Knee Scale (OKS) is a commonly used instrument to assess the symptoms and functional status in people with knee osteoarthritis. However, a Chinese version of this scale is not yet available. Objective: The objective of this study was to translate the OKS into Chinese and validate the Chinese version of OKS. Methods: The Chinese OKS was translated from the original English version following the recommendations of the International Society for Pharmacoeconomics and Outcomes Research. One hundred Chinese reading patients with knee osteoarthritis were recruited from local hospitals and physiotherapy clinics. Psychometric properties were evaluated in terms of test-retest reliability and internal consistency. Convergent validity was examined by Spearman rank correlation coefficient tests by comparing its score with the validated Chinese version of the Western Ontario and McMaster Universities Osteoarthritis Index and Health Outcome Survey Short Form-36. Results: Chinese OKS demonstrated excellent reliability (intraclass correlation coefficient = 0.88). Cronbach a of individual questions was > 0.7. Strong correlation was found between the Chinese OKS and the Western Ontario and McMaster Universities Osteoarthritis Index (r > 0.553, p < 0.001). Fairly strong negative correlation was also found between Chinese OKS and Health Outcome Survey Short Form-36 (p = -0.273 to -0.666, p < 0.05). Conclusion: The Chinese translated version of OKS is a reliable and valid instrument for clinical evaluation in Chinese reading patients with knee osteoarthritis

Acu-TENS and Postexercise Expiratory Flow Volume in Healthy Subjects

Transcutaneous Electrical Nerve Stimulation over acupoints (Acu-TENS) facilitates recovery of resting heart rate after treadmill exercise in healthy subjects. Its effect on postexercise respiratory indices has not been reported. This study investigates the effect of Acu-TENS on forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in healthy subjects after a submaximal exercise. Eleven male subjects were invited to the laboratory twice, two weeks apart, to receive in random order either Acu-TENS or Placebo-TENS (no electrical output from the TENS unit) over bilateral Lieque (LU7) and Dingchuan (EX-B1) for 45 minutes, before undergoing exercise following the Bruce protocol. Exercise duration, rate of perceived exertion (RPE), and peak heart rate (PHR) were recorded. Between-group FEV1 and FVC, before, immediately after, at 15, 30, and 45minutes postexercise, were compared. While no between-group differences in PHR, RPE, and FVC were found, Acu-TENS was associated with a longer exercise duration (0.9 min (P = .026)) and a higher percentage increase in FEV1 at 15 and 45 minutes postexercise (3.3 ± 3.7% (P = .013) and 5.1 ± 7.5% (P = .047), resp.) compared to Placebo-TENS. We concluded that Acu-TENS was associated with a higher postexercise FEV1 and a prolongation of submaximal exercise

Validation and reliability of the Physical Activity Scale for the Elderly in Chinese population

Objectives: Physical Activity Scale for the Elderly (PASE) is a widely used questionnaire in epidemiological studies for assessing the physical activity level of elderly. This study aims to translate and validate PASE in Chinese population. Design: Cross-sectional study. Subjects: Chinese elderly aged 65 or above. Methods: The original English version of PASE was translated into Chinese (PASE-C) following standardized translation procedures. Ninety Chinese elderly aged 65 or above were recruited in the community. Test-retest reliability was determined by comparing the scores obtained from two separate administrations by the intraclass correlation coefficient. Validity was evaluated by Spearman’s rank correlation coefficients between PASE and Medical Outcome Survey 36-Item Short Form Health Survey (SF-36), grip strength, single-leg-stance, 5 times sit-to-stand and 10-m walk. Results: PASE-C demonstrated good test-retest reliability (intraclass correlation coefficient  =0.81). Fair to moderate association were found between PASE-C and most of the subscales of SF-36 (rs=0.285 to 0.578, p<0.01), grip strength (rs=0.405 to 0.426, p<0.001), single-leg-stance (rs =0.470 to 0.548, p<0.001), 5 times sit-to-stand (rs =–0.33, p=0.001) and 10-m walk (rs =–0.281, p=0.007). Conclusion: PASE-C is a reliable and valid instrument for assessing the physical activity level of elderly in Chinese population

Acu-TENS Reduces Breathlessness during Exercise in People with Chronic Obstructive Pulmonary Disease

Background. Exertional dyspnoea limits level of physical activity in people with Chronic Obstructive Pulmonary Disease (COPD). This randomized, double-blinded, crossover study evaluated the effect of Acu-TENS, application of Transcutaneous Electrical Nerve Stimulation on acupoints, on breathlessness during exercise in people with COPD. Methods. Twenty-one participants, mean% predicted FEV1  50±21%, attended assessment followed by two intervention days, one week apart. On each intervention day, participants performed two endurance shuttle walk tests (ESWT) (Walk 1 and Walk 2). Walk 1 was performed without intervention and Walk 2 was performed with either Acu-TENS or Sham-TENS, in random order, for 45 minutes before and during Walk 2. Duration of each ESWT and dyspnoea score at isotime of Walk 1 and Walk 2 on each intervention day were compared. Between-group differences in ESWT duration and isotime dyspnoea were also compared. Results. At isotime of Walk 1 and Walk 2, Acu-TENS showed significant reduction in dyspnoea of −0.8 point (95% CI −0.2 to −1.4) but not in Sham-TENS [0.1 point (95% CI −0.4 to 0.6)]. Compared to Sham-TENS, Acu-TENS showed significant reduction in dyspnoea of −0.9 point (95% CI −0.2 to −1.6) while no between-group significance was found in ESWT duration. Conclusion. Acu-TENS alleviated dyspnoea during walking in people with COPD but did not increase walking duration

Semiconductor Spintronics

Spintronics refers commonly to phenomena in which the spin of electrons in a solid state environment plays the determining role. In a more narrow sense spintronics is an emerging research field of electronics: spintronics devices are based on a spin control of electronics, or on an electrical and optical control of spin or magnetism. This review presents selected themes of semiconductor spintronics, introducing important concepts in spin transport, spin injection, Silsbee-Johnson spin-charge coupling, and spindependent tunneling, as well as spin relaxation and spin dynamics. The most fundamental spin-dependent nteraction in nonmagnetic semiconductors is spin-orbit coupling. Depending on the crystal symmetries of the material, as well as on the structural properties of semiconductor based heterostructures, the spin-orbit coupling takes on different functional forms, giving a nice playground of effective spin-orbit Hamiltonians. The effective Hamiltonians for the most relevant classes of materials and heterostructures are derived here from realistic electronic band structure descriptions. Most semiconductor device systems are still theoretical concepts, waiting for experimental demonstrations. A review of selected proposed, and a few demonstrated devices is presented, with detailed description of two important classes: magnetic resonant tunnel structures and bipolar magnetic diodes and transistors. In most cases the presentation is of tutorial style, introducing the essential theoretical formalism at an accessible level, with case-study-like illustrations of actual experimental results, as well as with brief reviews of relevant recent achievements in the field.Comment: tutorial review; 342 pages, 132 figure

Effects of footwear on running economy in distance runners : a meta-analytical review

Objectives: Previous studies reported inconsistent findings about the effects of footwear on running economy, which is a surrogate measure of running performance. This meta-analytical review compared the running economy between running in barefoot, minimalists, and standard running shoes. Design: Meta-analysis. Methods: Electronic searches on MEDLINE, CINAHL, SPORTDiscus, and Cochrane Library databases were performed and the reference lists of the screened articles were also scrutinized. Two reviewers screened clinical trials that measured the oxygen cost of runners in different footwear conditions. Results: Thirteen studies were selected in this meta-analysis with a total of 168 runners included. Barefoot running was shown to be more economic than shod running (p < 0.01; standardized mean difference = −0.43; 95% Confidence Interval = −0.21 to −0.64; Z = 3.96). Similar pattern was found when comparing minimalist and shoe (p < 0.01; standardized mean difference = −0.49; 95% Confidence Interval = −0.29 to −0.70; Z = 4.64). The observed changes were of small effect. Conversely, no significant difference in the metabolic cost was found between running in minimalists and barefoot running (p = 0.45). Conclusions: Barefoot running or running in minimalist may require lower utilization of oxygen than shod running. Theoretically, the lower oxygen cost may improve long distance running performance. However, more than half of the runners in the included studies had previous barefoot experience and the findings may not apply to those habitual shod runners who are undergoing the transition. In addition, high risk of bias was reported in the included studies and quality study in the future is still warranted

Different relationships between the level of patellofemoral pain and quality of life in professional and amateur athletes

Background: Patellofemoral pain is a common orthopedic condition in the athletic population. Previous investigators focused on exploring the etiology and investigating the effectiveness of different treatment approaches for patellofemoral pain. However, the severity of symptoms and its corresponding impact on quality of life (QOL) in athletes at different skill levels have not been explored. Such information may help in formulating rehabilitation strategies targeting different levels of athletes. Objective: To compare the perception of patellofemoral symptoms and its impact on QOL between professional and amateur athletes with patellofemoral pain. Design: Cross-sectional study. Participants: Thirty-eight athletes with patellofemoral pain: 19 professional athletes from the Chinese national track and field team and 19 matched amateur participants recruited from a local track and field club. Main Outcome Measures: All participants completed the Chinese version of Kujala scale and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), which we used to quantify the severity of patellofemoral symptoms and QOL, respectively. Results: Professional athletes demonstrated a significantly higher level of patellofemoral symptoms (P < .001) and lower physical functioning subscore of SF-36 (P < .014) than did the amateur athletes. We also found a trend of a lower mental health subscore of SF-36 in professional athletes than in the amateurs (P = .07). The Kujala scale score was positively correlated with the subscore of “physical functioning” in both professional athletes (rs = 0.688, P = .001) and amateurs (rs = 0.751, P < .001). We also observed a trend of correlation between the subscore in the mental health domain and the severity of patellofemoral symptoms in professional athletes. Conclusions: Athletes at different elite levels might have varied perceptions of patellofemoral pain and the corresponding impact on physical aspects of quality of life. The results of this study may highlight the necessity of addressing psychosocial factors when formulating rehabilitation strategies in the athletic population with patellofemoral pain

Chinese adaptation and validation of the Knee Injury and Osteoarthritis Outcome Score (KOOS) in patients with knee osteoarthritis

Knee Injury and Osteoarthritis Outcome Score (KOOS) is a commonly used instrument to assess the symptoms and functional status in people with knee injuries, including knee osteoarthritis. While China ranked the top country in the absolute number of people aged 65 or above, yet there is no validated Chinese version of this outcome measurement. This study translated and validated the KOOS into Chinese version. Chinese KOOS was translated from the original English version following standard forward and backward translation procedures recommended by the International Society for Pharmacoeconomics and Outcomes Research. Survey was then conducted in clinical settings by a questionnaire comprised Chinese KOOS, WOMAC Osteoarthritis Index, and Short Form 36 health survey (SF-36). One hundred Chinese reading patients with knee osteoarthritis were recruited from the orthopaedic out-patient department in hospitals. Internal consistency of the instrument was measured by Cronbach alpha. Construct validity was examined by Spearman’s rank correlation coefficient (ρ) tests by comparing its score with the validated Chinese version of WOMAC Osteoarthritis Index and SF-36, while the test–retest reliability was evaluated by administering the questionnaires twice. Cronbach alpha values of individual questions and its overall value were above 0.70. Fairly strong association was found between the Chinese KOOS and the WOMAC Osteoarthritis Index (ρ = −0.37 to −0.86, p < 0.001). Diverse relationship was observed between Chinese KOOS and SF-36. Excellent test–retest reliability (ICC = 0.89–0.92) was demonstrated. The Chinese translated version of KOOS is a reliable and valid instrument for patients with knee osteoarthritis. The findings of current study might promote multinational investigations in this patient group