The Characteristics of Visual Function and Intervention in Deprivation Amblyopia in Limbal Dermoid Children After Keratoplasty: A Pilot Study of Adopting Flank-Mask Perceptual Learning

BackgroundTo compare visual acuity and CSF improvement with perceptual learning versus part-time patching in limbal dermoid children after keratoplasty.MethodsAll children in the limbal dermoid and normal group underwent visual acuity and CSF evaluation, and the normal group wore the optical defocus to simulate the corresponding visual acuity of the limbal dermoid group. Among the limbal dermoid children, 9 underwent perceptual learning(PL), and 8 underwent part-time patching for 6 months and were followed for 6 months to evaluate visual acuity and CSF.ResultsRegarding CSF, the area under log CSF (AULCSF) and the cutoff spatial frequency (cutoff SF) were obviously reduced in the limbal dermoid group compared with the optical defocus group and normal viewing group (1.29±0.27 vs 0.40±0.05 vs 0.70±0.05, and 5.38±0.75 vs 8.81±0.74 vs 14.81±0.89, all p value <0.05). Following PL, visual acuity increased from 0.63±0.11 to 0.32±0.09 (P=0.04) . Contrast sensitivity increased mainly in the low special frequencies as AULCSF improved from 0.49±0.15 to 0.73±0.18 (P=0.32), 0.78±0.21 (P=0.28), 0.80±0.19 (P=0.22) and 1.06±0.20 (P=0.04) from baseline to the 6th month in the PL group, while it remained unchanged in the part-time patching group.ConclusionsChildren suffering from limbal dermoid with amblyopia exhibited CSF deficits and perceptual learning was found to improve VA and CSF in the amblyopic eye better than patching.Trial registrationThe study was registered at clinicaltrials.gov (PRS, ID NCT03447041).

Abnormal capacitance–voltage behaviors of bismuth-doped CaCu3Ti4O12 ceramics

Ca[Formula: see text]Bi[Formula: see text]Cu3Ti4O[Formula: see text] ([Formula: see text] = 0.0, 0.1, 0.2 and 0.3; BCCTO) ceramics were prepared by traditional solid-state sintering method. All samples had pure cubic perovskite-like structure. A drastic grain size reduction was observed with bismuth doping. Dielectric spectra showed two obvious relaxation steps corresponding to two series of peaks in the imaginary part of electric modulus spectra and dielectric loss spectra too. Activation energy fitting by electric modulus spectra reflected different conducting segments in BCCTO ceramics of grains and oxygen vacancies below room temperature. Normalized capacitance dependent of extra bias showed different voltage–capacitance coefficients at special frequencies that suggested multirelaxation mechanisms related with grain and oxygen vacancy. A positive capacitance curvature implies dipolar relaxations in CCTO grains. Whereas a negative curvature suggests oxygen-related relaxations at the interface.

The Phonon Dissipation Mode in Nanofriction

The phonon dissipation is investigated through molecular dynamics (MD) simulation modeling graphene flake sliding on supported graphene in this paper. With the help of the advantage of MD, we explore the phonon mode variation of the substrate induced by the behavior of friction in terms of phonon densities of states. Moreover, phonon dissipation modes connected with the relative sliding velocity and the temperature of system are established respectively. The simulation results demonstrate phonon dissipation is represented as special phonon frequencies while those are closely related to the sliding velocities but would not shift as the change of temperatures. For an explanation of the special frequencies, we further simplify the model by directly adding the velocity to the atoms of the flake in the MD model, although it is impractical. It is found that a special frequency of phonon dissipation is generally in agreement with the sliding frequency at low temperature eliminating the interference of temperature in a range of velocities from 50m/s to 250m/s, namely, the velocity is directly related to the modes of phonon dissipation and friction, which is consistent with the previously reported result[1] that the velocity is an influence factor for friction both in experimental and theoretical researches. Therefore, the relationship makes possible the active control of friction. It is the first step toward using this method to reveal the fundamental questions in the study of atomic-scale friction.

The effect of resonance on the linear sampling method

Resonance frequency is examined for its effect on the linear sampling method (LSM). The aim of the study is to present an evaluation of occurrence of anomaly at some special frequencies in the LSM procedure. A comprehensive survey is done to analyze the destructive effect of resonance for LSM analysis. Analytical resonance calculations are used to verify the claim. Finally, a frequency selection method is proposed in order to overcome this phenomenon.

Structures and Optical Properties of Sm-Doped CuInTe2 Semiconductor

Since the rare earth based compounds have shown excellent properties such as luminescence and photo-electric transformation effect due to their 4f electronic structures. A novel Sm-doped CuIn1-xSmxTe2 semiconducting compounds have been designed and their crystal structures, microstructures and optical properties have been investigated using X-ray diffraction(XRD), scan electron microscopy (SEM), ultraviolet and visible spectrophotometer and Raman scattering. The results reveal that the doping of samarium into CuInTe2 (CIT) could stabilize the chalcopyrite structure, the lattice parameters shows fluctuation phenomenon with doping Sm in CIT. The SEM morphologies show that the grains tend to be agglomeration and form the column-like or the flake-like single crystals. The band gap Eg are corresponding to 1.25eV and 1.32eV before and after doping Sm with 0.1 mole into CuInTe2. Raman scattering analysis proves that Sm significantly adjusts the atomic vibrating models, and result in the losses of some vibrating peaks. It reveals that doping of Sm into CuInTe2 is helpful for the absorption of spectra with special frequencies.

Dynamically Feasible Trajectories for Three-DOF Planar Cable-Suspended Parallel Robots

This paper proposes a trajectory planning technique for planar three-degree-of-freedom cable-suspended parallel robots. Based on the kinematic and dynamic modelling of the architecture, force constraints that can guarantee that cables remain under tension are obtained. Periodic parametric trajectories that extend beyond the static workspace are designed. The trajectories involve combined translations and rotations. Substituting the trajectories into the force constraints, interval arithmetics is used to search for global conditions on the trajectory parameters which ensure that the trajectories are feasible. Special frequencies related to combined rotational and translational motions are exposed which can be used to better exploit cable-suspended robots. Moreover, it is observed that the special frequencies related to the translation are akin to the natural frequency of pendulum-like systems. The proposed trajectory planning approach can be used to plan combined rotational and translational dynamic trajectories that can extend beyond the static workspace of the mechanism, thereby opening novel applications and possibilities for cable-suspended robots.

Experimental Determination of Special Frequencies With Constant SL (Sound’s Level) in Noise of a Centrifugal Pump That Lead or Lag Due to the Speed Fluctuation

In this work, an experimental study about the hydrodynamic tonal noise in an industrial centrifugal pump with seven blades has been carried out. Noise measurements on the casing surface have been made for different flow rates with constant shaft speed. The experiment explains that in the frequency domain, the noise of centrifugal pump can be categorized in to two parts. First, as was expected, those frequencies which sound level of them is related to the flow rate and second, those ones that the sound level of them is constant and related to the pump structure. The experiment determines that the frequencies at the second type are so few, and they have correlation with BPF fluctuations. Also with deep notification, it can be considered that these special frequencies, lead or lag due to the speed fluctuations which produced by flow rate changes in nearly constant shaft speed.