A Wearable Asynchronous Brain-Computer Interface Based on EEG-EOG Signals With Fewer Channels.

OBJECTIVE: Brain-computer interfaces (BCIs) have tremendous application potential in communication, mechatronic control and rehabilitation. However, existing BCI systems are bulky, expensive and require laborious preparation before use. This study proposes a practical and user-friendly BCI system without compromising performance. METHODS: A hybrid asynchronous BCI system was developed based on an elaborately designed wearable electroencephalography (EEG) amplifier that is compact, easy to use and offers a high signal-to-noise ratio (SNR). The wearable BCI system can detect P300 signals by processing EEG signals from three channels and operates asynchronously by integrating blink detection. RESULT: The wearable EEG amplifier obtains high quality EEG signals and introduces preprocessing capabilities to BCI systems. The wearable BCI system achieves an average accuracy of 94.03±4.65%, an average information transfer rate (ITR) of 31.42±7.39 bits/min and an average false-positive rate (FPR) of 1.78%. CONCLUSION: The experimental results demonstrate the feasibility and practicality of the developed wearable EEG amplifier and BCI system. SIGNIFICANCE: Wearable asynchronous BCI systems with fewer channels are possible, indicating that BCI applications can be transferred from the laboratory to real-world scenarios.

Ultrasound Doppler fetal heart rate detection algorithm analyzes the correlation between twin selective fetal growth restriction and cord blood SFass fasL level.

OBJECTIVE: The paper uses ultrasound Doppler fetal heart rate detection algorithm to explore the placental characteristics of monochorionic twin pregnancy with selective fetal growth restriction, and discuss the correlation between selective fetal growth restriction and cord blood SFass FasL level. METHODS: From June 1, 2019 to June 1, 2020 in our hospital, 23 cases of selective fetal growth restriction and 32 cases of uncomplicated cases were included in the monochorionic twin pregnancies whose pregnancy was terminated in our hospital (control group) research. Perfusion was completed within 24 hours after delivery of the placenta. The umbilical arteries and veins of the two fetuses were respectively perfused with four different colors of pigments. The type of anastomoses was judged according to the color of the blood vessels on the placenta surface. RESULTS: The selective fetal growth restriction group was higher than the control group. In the selective fetal growth restriction group and the control group, the number of anastomoses of the placental superficial arterial artery, arterial vein and venous vein were 1.0 and 1.0, 3.0 and 2.0, 0.0 and 0.0, respectively; the placental superficial arterial artery, arterial vein and venous vein. The total diameters of the anastomosed blood vessels were 2.7 and 2.2, 4.0 and 3.4, 0.0 and 0.0 mm, respectively; the total number of superficial placental anastomosed blood vessels in the selective fetal growth restriction group and the control group were 3.5 and 3.5, respectively.The total diameters were 6.9 and 6.9, respectively 5.9mm. CONCLUSION: Uneven placental share and non-central attachment of the umbilical cord may be risk factors for selective fetal growth restriction in monochorionic twin pregnancy.