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Purpose: This retrospective cohort study aimed to investigate the effect of minimally invasive cochlear implantation (CI) on the vestibular function (VF) and residual hearing (RH) as well as their relationship in pediatric recipients before and after surgery. Methods: Twenty-four pediatric patients with preoperative low frequency residual hearing (LFRH) (250 or 500 Hz ≤ 80 dB HL) who underwent minimally invasive CI were enrolled. Pure-tone thresholds, the cervical/ocular vestibular-evoked myogenic potential (cVEMP/oVEMP), and video head impulse test (vHIT) were all evaluated in the 24 pediatric patients with preoperative normal VF before and at 1 and 12 months after surgery. The relationship between changes in hearing and VF was analyzed preoperatively and at 1 and 12 months postoperatively. Results: There were no significant differences on VF preservation and hearing preservation (HP) at both 1 and 12 months post-CI (p > 0.05). At 1 month post-CI, the correlations of the variations in vestibulo-ocular reflex (VOR) gains of horizontal semicircular canal (HSC) and posterior semicircular canal (PSC) and the shift in 250 Hz threshold were negatively correlated (r = − 0.41, p = 0.04 and r = − 0.43, p = 0.04, respectively). At 12 months post-CI, the shift in 250 Hz threshold negatively correlated to the variations in VOR gain of superior semicircular canal (SSC) (r = − 0.43, p = 0.04); the HP positively correlated to the variation in oVEMP-amplitude ratio (AR) (r = 0.41, p = 0.04). Conclusion: Our study confirmed that there were partial correlations between VF preservation and HP both in the short- and long-terms after atraumatic CI surgery, especially with the 250 Hz threshold. Regarding the variation of PSC function, the correlation with hearing status was variable with time after atraumatic CI surgery. Minimally invasive techniques for HP are successful and effective for the preservation of VF in pediatric patients both in the short- and long-terms. [ABSTRACT FROM AUTHOR]

Bend tubes have been widely used in aerospace equipment due to their excellent mechanical properties and chemical properties. However, elliptic deformation will occur in the process of bending, which will reduce the pressure bearing capacity and service life of the bend tube. In order to ensure the production quality of the bend tube, a method of detecting elliptic deformation based on the spine line of the tube is proposed in this article. Firstly, the spine line reconstruction method, which employs scanning points of the tube is proposed. Specifically, a voting points inspired spine line initialization method, and a bend part identification preferred spine line shape analysis method are designed. Secondly, the contour extraction method based on the natural coordinate system of the spine line is studied. Thirdly, the contour integrity assessment method based on the maximum center angle of the missing contour line is proposed. Contours satisfying the integrity will be used for ellipse fitting to determine the ovality of the tube. Finally, various bend tubes and standard elliptical cylinders are used to illustrate the effectiveness of the proposed method. Extensive experimental results show that our proposed method can extract the contour of the bend tube and analyze its deformation in only 7 s, and the ovality error is about 0.039%. Therefore, the method proposed in this paper can quickly and effectively analyze the elliptic deformation of the bend tube and can be used for online detection. [ABSTRACT FROM AUTHOR]

Autapses are a class of special synapses of neurons. In those neurons, their axons are not connected to the dendrites of other neurons but are attached to their own cell bodies. The output signal of a neuron feeds back to itself, thereby allowing the neuronal firing behavior to be self-tuned. Autapses can adjust the firing accuracy of a neuron and regulate the synchronization of a neuronal system. In this paper, we investigated the information capacity and energy efficiency of a Hodgkin-Huxley neuron in the noisy signal transmission process regulated by delayed inhibitory chemical autapse for different feedback strengths and delay times. We found that the information transmission, coding efficiency, and energy efficiency are maximized when the delay time is half of the input signal period. With the increase in the inhibitory strength of autapse, this maximization is increasingly obvious. Therefore, we propose that the inhibitory autaptic structure can serve as a mechanism and enable neural information processing to be energy efficient. [ABSTRACT FROM AUTHOR]

Previous experimental and theoretical studies have demonstrated that a weak signal can be amplified and optimized by the assistance of noise. The response of the system undergoes stochastic resonance (SR) like behavior. The underlying mechanisms are fairly simple and robust. This phenomenon has been observed in a large variety of systems, including physical and biological systems. In the nervous system, the majority of synaptic input is too weak to make neurons fire a spike. This weak (or subthreshold) signals detection is very important for animal survival, and pulse detection is a simple but basic task of neuronal information transmission and processing. Some studies have found that subthreshold signals can be transmitted by the application of external noise. However, neurons are subjected to various kinds of inherent noise. Recently, theoretical work has revealed that this inherent noise improves signals detection ability. The detection ability of a single neuron is limited, and the neuronal circuit can perform this task very well by detecting the synchronization of presynaptic potentials. Here, we review recent studies of subthreshold detection by both single neurons and neuronal circuits. [ABSTRACT FROM AUTHOR]