Aging effect and test-retest reliability of the sinusoidal harmonic acceleration test and velocity step test using nanotorque rotatory chair

Introduction:Rotatory chair testing has been used to evaluate horizontal canal function.Frequently used tests include sinusoidal harmonic acceleration test(SHAT)and velocity step test(VST).Objectives:Assessment of age effect on the SHAT and VST and assessment of test-retest reliability of the parameters of those two tests.Methods:A prospective study was performed on 100 subjects with no ear or vestibular complaints and normal vestibular evaluation.They were divided into two groups;Group A:below 50 years of age and Group B:50 years of age or above.SHAT was presented at frequencies 0.02,0.04,0.08,0.16,0.32,0.64 Hz with a peak velocity of 60°/s.VST was performed using a maximum velocity of 100°/s with acceleration and deceleration of 200°/s2.Thirty subjects were tested twice to assess reliability.Results:Study participants ranged in age from 20 to 67 years.Regarding group A,the mean age was30.92±7.31 and 55.36±4.61 for group B.No significant differences were found in SHAT parameters between the two groups.As well,there was no significant difference in VST per-rotatory time constant,however,post-rotatory time constant was significantly longer for Group B(P value<0.05).Intraclass correlation coefficient(ICC)values showed moderate to good reliability(ICC 0.5800.818)for SHAT parameters for the lower frequencies and indicated moderate reliability for VST time constant(ICC 0.5090.652).Conclusions:Age has no significant effect on the parameters of SHAT and VST.Test-retest reliability is generally good for both tests.

Anterolateral rotatory instability in vivo correlates tunnel position after anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft

AIM To quantitatively assess rotatory and anterior-posterior instability in vivo after anterior cruciate ligament(ACL) reconstruction using bone-patellar tendon-bone(BTB) autografts, and to clarify the influence of tunnel positions on the knee stability.METHODS Single-bundle ACL reconstruction with BTB autograft was performed on 50 patients with a mean age of 28 years using the trans-tibial(TT)(n = 20) and trans-portal(TP)(n = 30) techniques. Femoral and tibial tunnel positions were identified from the high-resolution 3 D-CT bone models two weeks after surgery. Anterolateral rotatory translation was examined using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging(MRI) 1.0-1.5 years after surgery, by measuring anterior tibial translation at the medial and lateral compartments on its sagittal images. Anterior-posterior stability was evaluated with a Kneelax3 arthrometer.RESULTS A total of 40 patients(80%) were finally followed up. Femoral tunnel positions were shallower(P < 0.01) and higher(P < 0.001), and tibial tunnel positions were more posterior(P < 0.05) in the TT group compared with the TP group. Anterolateral rotatory translations in reconstructed knees were significantly correlated with the shallow femoral tunnel positions(R = 0.42, P < 0.01), and the rotatory translations were greater in the TT group(3.2 ± 1.6 mm) than in the TP group(2.0 ± 1.8 mm)(P < 0.05). Side-to-side differences of Kneelax3 arthrometer were 1.5 ± 1.3 mm in the TT, and 1.7 ± 1.6 mm in the TP group(N.S.). Lysholm scores, KOOS subscales and reinjury rate showed no difference between the two groups.CONCLUSION Anterolateral rotatory instability significantly correlated shallow femoral tunnel positions after ACL reconstruction using BTB autografts. Clinical outcomes, rotatory and anterior-posterior stability were overall satisfactory in both techniques, but the TT technique located femoral tunnels in shallower and higher positions, and tibial tunnels in more posterior positions than the TP technique, thus increased the anterolateral rotation. Anatomic ACL reconstruction with BTB autografts may restore knee function and stability.

Atlantoaxial rotatory displacement in children

AIM To correlate the Pang and Lee class with the clinical course in a consecutive series of patients presenting with painful torticollis.METHODS Forty-seven dynamic rotational computed tomography(CT) scans in 35 patients were classified into one of the five types defined by Pang and Li, including types Ⅰ(atlantoaxial rotatopry fixation), Ⅱ("pathologic stickiness" without crossover of C1 on C2), Ⅲ("pathologic stickiness" with crossover of C1 on C2), Ⅳ(normal or muscular torticollis), and Ⅴ(diagnostic grey zone). The Pang and Li class was then compared with the radiologist's report, which was graded abnormal, diagnosis of rotatory subluxation or fixation, or non-diagnostic. Medical records were reviewed and the clinical course was compared among the five subtypes.RESULTS We reviewed 47 CT scans in 35 patients, and the majority were performed without sedation. The average age was 7.7 years(4-14 years old) and associated conditions included minor trauma(20%), surgical procedures around the head and neck(29%), and Grisels syndrome(20%). Twenty-six percent of our studies fell within the pathologic spectrum(5% type 1 or rotatory fixation, 21% types 2 and 3 or rotatory subluxation), while 45% were classified as muscular torticollis(45%) and 28% fell within the diagnostic grey zone. Seven radiologists interpreted these studies, and their interpretation was discordant in 45% of cases. Clinical resolution occurred in 27 of 29 cases for which follow-up was available. One of two patients with fixed rotatory subluxation required a C1-C2 arthrodesis.CONCLUSION The Pang and Li classification characterizes a spectrum of abnormalities in rotation to facilitate communication, although the indications for dynamic CT scan should be further defined.

Optical Rotatory Dispersion Measurement of D-Glucose with Fixed Polarizer Analyzer Accessory in Conventional Spectrophotometer

In the sample compartment of a conventional spectrophotometer, mounting of a polarizer before sample and an analyzer behind sample allows the determination of the optical rotatory dispersion of optical active media by measurement of the transmission ratio of crossed and parallel arranged polarizer and analyzer. A formula for the determination of the angle of rotation is derived from the transmission ratio. The arrangement is applied to determine the molar optical rotation of D-glucose in water in the wavelength range from 220 nm to 820 nm.

Spectral polarization-encoding of broadband laser pulses by optical rotatory dispersion and its applications in spectral manipulation

We propose a kind of spectral polarization-encoding(SPE)for broadband light pulses,which is realized by inducing optical rotatory dispersion(ORD),and decoded by compensating ORD.Combining with polarization-sensitive devices,SPE can not only work to control polarization-dependent transmission for central wavelength or bandwidth-tunable filtering,but also can be used for broadband regenerative or multi-pass amplification with a polarization-dependent gain medium to improve output bandwidth.SPE is entirely passive thus very simple to be designed and aligned.By using an ORD crystal with a good transmission beyond 3-μm mid-infrared region,e.g.,Ag Ga S_(2),SPE promises to be applied for the wavelength tuning lasers in mid-infrared region,where the tunning devices are rather under developed compared with those in visible and near-infrared region.

DYNAMIC RESPONSE OF LAMINATED ORTHOTROPIC SPHERICAL SHELLSINCLUDING TRANSVERSE SHEAR DEFORMATION AND ROTATORY INERTIA

In this paper.the equations of motion of axisymmetrically laminated cylindrical orthotropic spherical shells are derived.Theeffects of transverse shear deformation and rotatory inertia are considered.On this basis,the dynamic response of spherical shells under axisymmetric dynamic load is calculated using the finite difference method The effects of material parameters.structural parameters and transverse shear dgformation are discussed.

Treatment of rotatory subluxation of the scaphoid by scapho-trapezoid limited arthrodesis

Objective To introduce a new procedure for treatment of rotatory subluxation of the scaphoid. Methods Eighteen patients with rotatory subluxation of the scaphoid were divided into five types according to clinical manifestation and cause: type Ⅰ (predynamic) 1 case,type Ⅱ (dynamic) 2 cases, type Ⅲ (static) 7 cases, type Ⅳ (degenerative) 3 cases, type Ⅴ( secondary) 5 cases. All cases underwent scapho-trapezio-trapezoid limited wrist arthrodesis. Results The follow-up ranged from 6 months to 3 years. The results showed that the all rotatory subluxatiopn of scaphoid in the study had been corrected with satisfactory fusion and painless wrist. The average grip strength was 90% of the normal wrist, and the average range of motion was 62% of the opposite side. Conclusion Scapho-trapezio-trapezoid limited arthrodesis is a reliable and useful procedure for treatment of chronic andChina Medical Abstracts(Surgery) static rotatory subluxation of the scaphoid. 15 refs,2 figs.

Optimum Anti-erosion Structures and Anti-erosion Mechanism for Rotatory Samples Inspired by Scorpion Armor of Parabuthus transvaalicus

Solid particle erosion on the material surfaces is a very common phenomenon in the industrial field,which greatly affects the efficiency,service life,and even poses a great threat to life safety.However,current research on erosion resistance is not only inefficient,but also limited to the improvement of hardness and toughness of materials.Inspired by typical scorpion(Parabuthus transvaalicus),biomimetic functional samples with exquisite anti-rosion structures were manufactured.Macroscopic morphology and structure of the biological prototype were analyzed and measured.According to above analysis,combined with response surface methodology,a set of biomimetic samples with different structural parameters were fabricated by using 3D printing technology.The anti-crosion performance of these biomimetic samples was investigated using a blasting jet machine.Based on the results of blasting jet test,as well as regression analysis and fiting,the optimal structural parameters were obtained.In addition to the static test conditions,the optimal biomimetic sample was also eroded in rotating condition and showed excellent erosion resistance property.The presence of bump and groove structures,on the one hand,reduced the croded area of biominetic sample surface.On the other hand,they made the airlow turbulent and consequently reduced the impact cnergy of solid particles,which significantly improved the erosion resistance of biomimetic materials.This study provides a new strategy to improvethe service life of components easily affected by erosion in the aviation,energy and military fields.

The theoretical study of optical rotatory power of D2-C76

Based on the theory of the reaction of electromagnetic field with molecule, a formula for the optical rotatory power is given. And using this formula, the optical rotatory power of D2-C76 is determined to be about 1°/cm.

Optical filter based on internal reflection and optical rotatory dispersion of NaBrO_3 crystal

Based on the optical rotatory dispersion and zero reflection of the p-polarization light at the Brewster angle, a novel optical filter that employs only one NaBrO3 crystal and one polarizer are proposed and demonstrated. Performance of the optical filter is studied both theoretically and experimentally. Results show that the green light is becomes nearly extinct when the angles of the polarizer are set at 80°and 260°, whereas the red light becomes nearly extinct when the angles of the polarizer are set at 116°and 296°.Isolation of more than 8 dB can be achieved. The measured extinction ratios are 12.3 and 12.6 dB for green and red lights, respectively.

HIGH-FREQUENCY VIBRATIONS OF CORRUGATED CYLINDRICAL PIEZOELECTRIC SHELLS

Coupled extensional and flexural cylindrical vibrations of a corrugated cylindrical piezoelectric shell consisting of multiple pieces of circular cylindrical surfaces smoothly connected along their generatrix are studied. To validate the results for the case of relatively thick shells or equivalently high-frequency modes with short wavelengths, existing analysis is extended by considering shear deformation and rotatory inertia. An analytical solution is obtained. Based on the solution, resonant frequencies and mode shapes are calculated.

On Axially Symmetric Vibrations of Fluid Filled Poroelastic Spherical Shells

Employing Biot’s theory of wave propagation in liquid saturated porous media, waves propagating in a hollow poroelastic closed spherical shell filled with fluid are studied. The frequency equation of axially symmetric vibrations for a pervious and an impervious surface is obtained. Free vibrations of a closed spherical shell are studied as a particular case when the fluid is vanished. Frequency as a function of ratio of thickness to inner radius is computed in absence of dissipation for two types of poroelastic materials each for a pervious and an impervious surface. Results of previous works are obtained as a particular case of the present study.

A Nonlinear Dynamical Theory of Non-Classical Plates

In ths paper. a new nonlinear formulation of plates. including shear and rotatory inertia and transverse normal stress effects, is developed by means of general assumptions, of which the von Karman-type formulation and some thick plate theories are special cases. To keep the formulation fairly general, the problem addressed in this paper simultaneously includes: the effects of shear deformation according to the geometric deformation similarity of the crosssection, the rotatory inertia, and the transverse normal stress. The three-dimensional compatible equations are applied to derive the basic equations. Numerical results are given for linear and non-linear analysis of plates.

Thermo-Economic Optimization of Solar Thermal Devices by Coherent Integration of Technologies

Radiation is a form of energy where the angular variable of the direction of its photons has a primary importance, particularly for radiation concentration processes, which are essential tools to reach high temperatures from radiation beams (as the solar ones) with moderate intensities. Solar radiation cannot be used directly to feed thermodynamic cycles, and optical concentration must be applied to that goal. In general, reflection from mirrors is preferred to refraction by lenses in this case, because they have less optical aberrations. Concentration conveys very high temperatures in the receiver. However, the higher the temperature, the lower the efficiency of the solar thermal apparatus. Besides that, economy also suffers quite a lot when going to very high concentration factors, which is one of the main burdens in the development of Solar Thermal Energy. A new configuration of solar radiation concentrator is presented. It includes a salient innovation in the way the mirrors are given the right curvature by mechanical forces. Those mirrors are originally flat and do not need any special thermal treatment for this purpose. The whole device concept has been guided by the principle of thermoeconomic coherence, which requires similar efforts in all degrees of freedom that have strong influence in the performance and cost of the system. The paper shows the decision tree that has oriented the project, following the principle of equilibrium in efforts, which leads to a design window of moderate values in the main variables. The prototype of this new configuration has already been built, and the first stage of research is considered to be finished, because the prototype has shown excellent conditions to include selected (fitting) technologies at a very low cost.