The traditional paradigm of motor-imagery-based brain-computer interface (BCI) is abstract, which cannot effectively guide users to modulate brain activity, thus limiting the activation degree of the sensorimotor cortex. It was found that the motor imagery task of Chinese characters writing was better accepted by users and helped guide them to modulate their sensorimotor rhythms. However, different Chinese characters have different writing complexity (number of strokes), and the effect of motor imagery tasks of Chinese characters with different writing complexity on the performance of motor-imagery-based BCI is still unclear. In this paper, a total of 12 healthy subjects were recruited for studying the effects of motor imagery tasks of Chinese characters with two different writing complexity (5 and 10 strokes) on the performance of motor-imagery-based BCI. The experimental results showed that, compared with Chinese characters with 5 strokes, motor imagery task of Chinese characters writing with 10 strokes obtained stronger sensorimotor rhythm and better recognition performance (P < 0.05). This study indicated that, appropriately increasing the complexity of the motor imagery task of Chinese characters writing can obtain stronger motor imagery potential and improve the recognition accuracy of motor-imagery-based BCI, which provides a reference for the design of the motor-imagery-based BCI paradigm in the future.
A new urine analysis core module based on high performance 32-bit microprocessor and high precision color sensor was presented. A novel optical structure and a specific circuit were applied to improve measurement precision and temperature was used to compensate for results in this core module. The information of urine test peice, such as all original data and color RGB value, reflectivity, semi-quantitative level, etc. can be output. The results showed that the measuring precision was about 95% or above with ideal stability and reliability using this presented core module, which can be conveniently applied in various urine analyzers, and can greatly decrease the cost of urine analyzers in development and production.
Objectives To investigate the correlation between blood total cholesterol (TC) and prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL) and to provide references for clinical treatment and prognosis assessment. Methods We included 232 ISSNHL patients with total deafness in Wenzhou Central Hospital from June 2015 to March 2017 using a prospective cohort design. Recording information including age, gender, hypertension, diabetes mellitus, vertigo, level of blood total cholesterol (TC), level of triglyceride (TG), level of low-density lipoprotein (LDL-C) and LDL/HDL ratio (LDL-C/HDL-C) were collected. Correlation between the prognosis of ISSNHL and blood total cholesterol were analyzed by univariable and multivariable logistic regression analysis. Results The clinical effective rate of patients with TC ranging from 5.2 mmol/L to 6.2 mmol/L was higher than that of patients with TC lower than 5.2 mmol/L (univariable: RR=6.49, 95%CI 3.16 to 13.30, P<0.001; multivariable-adjusted covariates: RR=6.15, 95%CI 2.66 to 14.3,P<0.001) with significant difference. No significant difference was found between patients with TC lower than 5.2 mmol/L and patients with TC higher than 6.2 mmol/L (univariable: RR=1.02, 95%CI 0.52 to 2.00,P=0.960; multivariable-adjusted covariates: RR=1.61, 95%CI 0.55 to 4.73, P=0.386). Gender-specific analysis showed for both male and female groups, the effective rates of patients with TC ranging from 5.2 mmol/L to 6.2 mmol/L were significantly higher than those of patients with TC lower than 5.2 mmol/L. There was no significant difference between patients with TC lower than 5.2 mmol/L and patients with TC higher than 6.2 mmol/L (P>0.05) in either male group or female group. Conclusion The current study suggests that patients with levels of TC ranging from 5.2 mmol/L to 6.2 mmol/L predicts the best prognosis.
Objective To observe the therapeutic effect of autologous neurosensory retinal transplantation in repairing unhealed giant macular hole after pars plana vitrectomy (PPV). MethodsA prospective clinical study. From July 2022 to December 2023, 12 patients (12 eyes) with refractory large macular hole who received autologous neurosensory retinal transplantation treatment in Department of Ophthalmology of the First Affiliated Hospital of Zhengzhou University were selected for the study. The macular hole in affected eyes still did not close after PPV combined with inner limiting membrane removal or tamponade, and the diameter of macular hole were greater than 600 μm. All affected eyes received best corrected visual acuity (BCVA) and optical coherence tomography (OCT) examinations. The BCVA examination employed the international standard visual acuity chart, with results converted to logarithm of the minimum angle of resolution (logMAR) visual acuity for statistical analysis. During the surgery, a piece of healthy retinal neuroepithelial tissue, approximately 0.3 optic disc diameters larger than the macular hole, was removed from the upper retinal periphery and used as a graft. The graft was inserted into the macular hole with the aid of intraoperative OCT. Post-surgery, the vitreous cavity was filled with silicone oil or sterile air. The follow-up period after surgery was 6 months. The thickness of the retinal grafts was measured using the same equipment as before surgery at 3 days, 1, 3, and 6 months post-surgery. The primary focus was on observing the macular hole closure rate and changes in BCVA at 6 months post-operation. A paired t-test was used to compare BCVA before and after surgery. Results In the sample of 12 cases (12 eyes), there were 5 males with 5 eyes and 7 females with 7 eyes. The mean age was (50.4±12.6) years. The mean macular hole diameter was (1 085.6±344.0) μm; The mean eye axis length was (27.64±4.19) mm. At 6 months after surgery, all affected eyes showed macular hole were completely closed (100.0%, 12/12). The thickness of the retinal graft was measured as (206.8±21.0), (170.8±23.3), (165.6±31.6), and (157.9±31.1) μm at 3 days, 1, 3, and 6 months post-surgery, respectively. At before and 6 months after surgery, the logMAR BCVA of the affected eyes was 1.28±0.39 and 0.95±0.22, respectively. The difference in logMAR BCVA before and after surgery was statistically significant (t=3.40, P＜0.05). Conclusion Autologous neurosensory retinal transplantation could effectively improve the closure rate of refractory large macular hole and improve or stabilize vision in the short run.
In order to overcome the influence of stray light and impurity on the image of video laryngoscope, we designed an optical structure by using TracePro, a simulation software, to imitate optical path status. Images are captured by CMOS sensor which has the size of 4.5 mm×18 mm and the pixel size is 1.75 μm×1.75 μm. The sensor is placed in the elbow of the laryngoscope, and the elbow has the size of 9 mm×10 mm. As a result, the video laryngoscope could meet the requirements, including wide viewing angle (80°), short focal length (2.8 mm), long working distance (10 cm), and least impurity. In the test, the image was clear and there was no facula or impurity in the condition of required illumination, and thus stray light and image impurity were eliminated and the image quality was improved.
According to the development status of wearable technology and the demand of intelligent health monitoring, we studied the multi-function integrated smart watches solution and its key technology. First of all, the sensor technology with high integration density, Bluetooth low energy (BLE) and mobile communication technology were integrated and used in develop practice. Secondly, for the hardware design of the system in this paper, we chose the scheme with high integration density and cost-effective computer modules and chips. Thirdly, we used real-time operating system FreeRTOS to develop the friendly graphical interface interacting with touch screen. At last, the high-performance application software which connected with BLE hardware wirelessly and synchronized data was developed based on android system. The function of this system included real-time calendar clock, telephone message, address book management, step-counting, heart rate and sleep quality monitoring and so on. Experiments showed that the collecting data accuracy of various sensors, system data transmission capacity, the overall power consumption satisfy the production standard. Moreover, the system run stably with low power consumption, which could realize intelligent health monitoring effectively.
Ultra-sensitive and quantitative analysis of proteins, nucleic acid, virus and other biochemical species are critical technologies for effective dianosis of disease, as well as medical studies. Silicon nanowires field-effect transistor (SiNWs-FET) biosensor is one of the most promising powerful platforms for label-free, real-time, ultra-sensitive detection of analyte. Here, the working principle of SiNWs-FET biosensor and the applications of SiNWs-FET biosensors in medicine were introduced. Moreover, the methods for enhancing the sensitivity of SiNWs-FET biosensor were discussed. Lastly, the prospecting of SiNWs-FET biosensor was presented.
Plantar pressure distribution can reflect the force of several key points on foot while standing and walking. A comprehensive understanding of the plantar pressure distribution makes great sense in the following aspects:the understanding of the normal foot biomechanics and function, clinical diagnosis, measurement of disease extent, postoperative efficacy evaluation, and rehabilitation research. A simple plantar pressure measurement device was designed in this study. This paper uses FlexiForce flexible sensor to pickup plantar pressure signal and USB A/D board to do data acquisition. The data are transferred into a laptop and processed by a VB-based software which can display, remember and replay the data. We chose patients with hallux valgus and normal people to measure the pressure distribution and make contrast analysis of plantar pressure with this device. It can be concluded that people with hallux valgus have higher pressure on the second metatarsophalangeal joint and the distribution move outward. The plantar pressure of patients postoperative could be greatly improved compared to the preoperative. The function of this device has been confirmed.
The requirement for unconstrained monitoring of heartbeat during sleep is increasing, but the current detection devices can not meet the requirements of convenience and accuracy. This study designed an unconstrained ballistocardiogram (BCG) detection system using acceleration sensor and developed a heart rate extraction algorithm. BCG is a directional signal which is stronger and less affected by respiratory movements along spine direction than in other directions. In order to measure the BCG signal along spine direction during sleep, a 3-axis acceleration sensor was fixed on the bed to collect the vibration signals caused by heartbeat. An approximate frequency range was firstly assumed by frequency analysis to the BCG signals and segmental filtering was conducted to the original vibration signals within the frequency range. Secondly, to identify the true BCG waveform, the accurate frequency band was obtained by comparison with the theoretical waveform. The J waves were detected by BCG energy waveform and an adaptive threshold method was proposed to extract heart rates by using the information of both amplitude and period. The accuracy and robustness of the BCG detection system proposed and the algorithm developed in this study were confirmed by comparison with electrocardiogram (ECG). The test results of 30 subjects showed a high average accuracy of 99.21% to demonstrate the feasibility of the unconstrained BCG detection method based on vibration acceleration.
The current quantitative methods of bilirubin have disadvantages such as high cost and low sensitivity. Due to the negative correlation between the level of serum bilirubin and the risk of cardiovascular diseases, a fluorescent ratiometric film sensor was developed aiming at bilirubin detection at low level concentration. Blue-emitting and red-emitting gold nanoclusters were assembled into the same film using layer-by-layer self-assembly technology. Detection of bilirubin was achieved based on the intensity ratio of the two nanoclusters. Bilirubin exposure causes fluorescent quenching of the film. The fluorescence intensity ratio of the two cluster probes had quantitative relationship versus bilirubin concentration. Based on this film sensor, a portable fluorescence detection system was designed for the ratiometric sensing of bilirubin. The hardware of the system was mainly composed of main control chip STM32F407, TSL237 and TSL238T optical frequency sensor. A light-avoiding dark room and detection light path were designed through three-dimensional printing to reduce the interference from ambient light and improve detection accuracy. Experimental results showed that the proposed detection system had strong anti-interference, good stability and accuracy. The linear coefficient of bilirubin detected by this system was 0.987. The system presented good results in reproducible experiments and possessed a good linear relationship with the data obtained by standard spectrofluorometer. The portable system is expected to detect serum bilirubin at low levels.