Is Sham Laser a Valid Control for Acupuncture Trials?

Methodological problems of acupuncture trials focus on adequate placebo controls. In this trial we evaluated the use of sham laser acupuncture as a control procedure. Thirty-four healthy volunteers received verum laser (invisible infrared laser emission and red light, 45 s and 1 J per point) and sham laser (red light) treatment at three acupuncture points (LI4, LU7 and LR3) in a randomized, double-blinded, cross-over design. The main outcome measure was the ratio of correct to incorrect ratings of treatment immediately after each session. The secondary outcome measure was the occurrence of deqi-like sensations at the acupuncture points and their intensity on a 10-fold visual analog scale (VAS; 10 being the strongest sensible sensation). We pooled the results of three former trials to evaluate the credibility of sham laser acupuncture when compared to needle acupuncture. Fifteen out of 34 (44%) healthy volunteers (age: 28 ± 10.7 years) identified the used laser device after the first session and 14 (41%) after the second session. Hence, both treatments were undistinguishable (P = .26). Deqi-like sensations occurred in 46% of active laser (2.34 VAS) and in 49.0% of sham laser beams (2.49 VAS). The credibility of sham laser was not different from needle acupuncture. Sham laser acupuncture can serve as a valid placebo control in laser acupuncture studies. Due to similar credibility and the lack of sensory input on the peripheral nervous system, sham laser acupuncture can also serve as a sham control for acupuncture trials, in order to evaluate needling effects per se

Tube Drawing with Tilted Die: Texture, Dislocation Density and Mechanical Properties

Anisotropic behavior is a key characteristic for understanding eccentricity in tubes. In this paper, the effect of using a tilted die during tube drawing on eccentricity, texture, dislocation density, and mechanical properties is shown. Copper tubes were drawn with a +/- 5 degrees tilted die for two passes. The increase or decrease in eccentricity can be controlled by controlling the angle of the tilted die. Two types of textures have been developed during tube drawing, namely plane strain and uniaxial types. Plain strain type texture is mainly characterized by the beta fiber with a dominant copper component {112}. The uniaxial deformation type is dominated by the fiber, as commonly found by wire drawing. Texture sharpness increases with increasing drawing strain, and the texture varies significantly between the maximum and minimum wall thickness. This texture variation between maximum and minimum wall thickness has no significant influence on mechanical properties, which are more or less similar, but the increase in strength after each drawing pass is apparent. The dislocation density is low for the as-received tubes due to recovery and recrystallization. This is consistent with the as-received texture dominated by the cube component {001}. During tube drawing, dislocation density increases as a function of the deformation strain. The variation of dislocation density between the maximum and minimum wall thickness in the tube deformed with -5 degrees tilted die is higher than the variation in the tube deformed with +5 degrees tilted die

Deqi sensations without cutaneous sensory input: results of an RCT

<p>Abstract</p> <p>Background</p> <p>Deqi is defined in relation to acupuncture needling as a sensory perception of varying character. In a recently published sham laser validation study, we found that subjects in the verum and the sham laser group experienced deqi sensations. Therefore, we aim to further analyze whether the perceptions reported in the two study arms were distinguishable and whether expectancy effects exhibited considerable impact on our results.</p> <p>Methods</p> <p>A detailed re-analysis focusing on deqi sensations was performed from data collected in a previously published placebo-controlled, double-blind, clinical cross-over trial for a sham laser evaluation. Thirty-four healthy volunteers (28 ± 10.7 years; 16 women, 18 men) received two laser acupuncture treatments at three acupuncture points LI4 (hégu), LU7 (liéque), and LR3 (táichong); once by verum laser and once using a sham device containing an inactive laser in randomized order. Outcome measures were frequency, intensity (evaluated by visual analogue scale; VAS), and quality of the subjects' sensations perceived during treatments (assessed with the "acupuncture sensation scale").</p> <p>Results</p> <p>Both, verum and the sham laser acupuncture result in similar deqi sensations with regard to frequency (p-value = 0.67), intensity (p-value = 0.71) and quality (p-values between 0.15 - 0.98). In both groups the most frequently used adjectives to describe these perceptions were "spreading", "radiating", "tingling", "tugging", "pulsing", "warm", "dull", and "electric". Sensations reported were consistent with the perception of deqi as previously defined in literature. Subjects' conviction regarding the effectiveness of laser acupuncture or the history of having received acupuncture treatments before did not correlate with the frequency or intensity of sensations reported.</p> <p>Conclusions</p> <p>Since deqi sensations, described as sensory perceptions, were elicited without any cutaneous sensory input, we assume that they are a product of non-specific effects from the overall treatment procedure. Expectancy-effects due to previous acupuncture experience and belief in laser acupuncture do not seem to play a major role in elicitation of deqi sensations. Our results give hints that deqi might be a central phenomenon of awareness and consciousness, and that its relevance should be taken into account, even in clinical trials. However, further research is required to understand mechanisms underlying deqi.</p

Crystallographic texture gradient along the wall thickness of an SF-copper tube

Metallic tubes usually show heterogeneities along circumference and through wall thickness. Local textureanalysis by synchrotron diffraction and global texture analysis by neutron diffraction was used describing texturevariations related to the wall thickness. Test sample was an SF-Cu tube with outer diameter of 140mm and anaverage wall thickness of 10 mm. The texture is dominated by the cube component {001} 〈100〉. Other minorcomponents are rotated cube {013} 〈100〉, Goss {011} 〈100〉, Cu {112} 〈111〉, brass {110} 〈112〉, S {123}〈634〉. The texture gradient over the wall thickness shows a remarkable variation of the sharpness of the cubecomponent. Other components show only little variation. Comparing samples obtained at maximum wallthickness and at minimum wall thickness one can see that the wall thickness has an influence on the globaltexture as well as texture gradient. Another interesting result is, that global textures measured directly byneutrons and averaged global textures, calculated from the set of local measurements by synchrotron diffraction,agree surprisingly well despite their different resolution

Tube Drawing with Tilted Die: Texture, Dislocation Density and Mechanical Properties

Anisotropic behavior is a key characteristic for understanding eccentricity in tubes. Inthis paper, the effect of using a tilted die during tube drawing on eccentricity, texture, dislocationdensity, and mechanical properties is shown. Copper tubes were drawn with a 5 tilted die fortwo passes. The increase or decrease in eccentricity can be controlled by controlling the angle ofthe tilted die. Two types of textures have been developed during tube drawing, namely planestrain and uniaxial types. Plain strain type texture is mainly characterized by the fiber with adominant copper component {112}. The uniaxial deformation type is dominated by the fiber, as commonly found by wire drawing. Texture sharpness increases with increasing drawingstrain, and the texture varies significantly between the maximum and minimum wall thickness.This texture variation between maximum and minimum wall thickness has no significant influenceon mechanical properties, which are more or less similar, but the increase in strength after eachdrawing pass is apparent. The dislocation density is low for the as-received tubes due to recovery andrecrystallization. This is consistent with the as-received texture dominated by the cube component{001}. During tube drawing, dislocation density increases as a function of the deformationstrain. The variation of dislocation density between the maximum and minimum wall thicknessin the tube deformed with 5 tilted die is higher than the variation in the tube deformed with+5 tilted die