Congenital Radioulnar Synostosis: A Case Report and Review of Various Osteotomies.

Introduction: Congenital radioulnar synostosis is a rare deformity of the forearm characterized by a malformation of the proximal aspect of the radius and ulna. Various modalities of treatment options available include observation, excision of the synostosis and placing an interposition material, or performing derotation osteotomy. Several types of osteotomies at different forearm levels have been described in the literature. Case Report: A 5-year-old female presented with bilateral congenital radioulnar synostosis which was treated with percutaneous corrective osteotomy and Joshi's external stabilizing system fixator application. Conclusion: We describe the management of congenital radioulnar synostosis in a 5-year-old female child using a novel minimally invasive, single-staged procedure . This innovative technique provided the patient with a good functional outcome and she could return to her daily activities with a satisfactory range of motion.

A Low-Power Wireless System for Predicting Early Signs of Sudden Cardiac Arrest Incorporating an Optimized CNN Model Implemented on NVIDIA Jetson.

The survival rate for sudden cardiac arrest (SCA) is low, and patients with long-term risks of SCA are not adequately alerted. Understanding SCA's characteristics will be key to developing preventive strategies. Many lives could be saved if SCA's early onset could be detected or predicted. Monitoring heart signals continuously is essential for diagnosing sporadic cardiac dysfunction. An electrocardiogram (ECG) can be used to continuously monitor heart function without having to go to the hospital. A zeolite-based dry electrode can provide safe on-skin ECG acquisition while the subject is out-of-hospital and facilitate long-term monitoring. To the ECG signal, a low-power 1 µW read-out circuit was designed and implemented in our prior work. However, having long-term ECG monitoring outside the hospital, i.e., high battery life, and low power consumption while transmission and reception of ECG signal are crucial. This paper proposes a prototype with a 10-bit resolution ADC and nRF24L01 transceivers placed 5 m apart. The system uses the 2.4 GHz worldwide ISM frequency band with GFSK modulation to wirelessly transmit digitized ECG bits at 250 kbps data rate to a physician's computer (or similar) for continuous monitoring of ECG signals; the power consumption is only 11.2 mW and 4.62 mW during transmission and reception, respectively, with a low bit error rate of ≤0.1%. Additionally, a subject-wise cross-validated, three-fold, optimized convolutional neural network (CNN) model using the Physionet-SCA dataset was implemented on NVIDIA Jetson to identify the irregular heartbeats yielding an accuracy of 89% with a run time of 5.31 s. Normal beat classification has an F1 score of 0.94 and a ROC score of 0.886. Thus, this paper integrates the ECG acquisition and processing unit with low-power wireless transmission and CNN model to detect irregular heartbeats.

Asymmetric 2D MoS2 for Scalable and High-Performance Piezoelectric Sensors.

Piezoelectricity in two-dimensional (2D) transition-metal dichalcogenides (TMDs) has attracted significant attention due to their unique crystal structure and the lack of inversion centers when the bulk TMDs thin down to monolayers. Although the piezoelectric effect in atomic-thickness TMDs has been reported earlier, they are exfoliated 2D TMDs and are therefore not scalable. Here, we demonstrate a superior piezoelectric effect from large-scale sputtered, asymmetric 2D MoS2 using meticulous defect engineering based on the thermal-solvent annealing of the MoS2 layer. This yields an output peak current and voltage of 20 pA and 700 mV (after annealing at 450 °C), respectively, which is the highest piezoelectric strength ever reported in 2D MoS2. Indeed, the piezoelectric strength increases with the defect density (sulfur vacancies), which, in turn, increases with the annealing temperature at least up to 450 °C. Moreover, our piezoelectric MoS2 device array shows an exceptional piezoelectric sensitivity of 262 mV/kPa with a high level of uniformity and excellent performance under ambient conditions. A detailed study of the sulfur vacancy-dependent property and its resultant asymmetric structure-induced piezoelectricity is reported. The proposed approach is scalable and can produce advanced materials for flexible piezoelectric devices to be used in emerging bioinspired robotics and biomedical applications.

Stable and high-performance piezoelectric sensor via CVD grown WS2.

Piezoelectric materials are widely used as electromechanical couples for a variety of sensors and actuators in nanoscale electronic devices. The majority of piezoelectric devices display lateral patterning of counter electrodes beside active materials such as two-dimensional transition metal dichalcogenides (2D TMDs). As a result, their piezoelectric output response is strongly dependent on the lattice orientation of the 2D TMD crystal structure, limiting their piezoelectric properties. To overcome this issue, we fabricated a vertical sandwich design of a piezoelectric sensor with a conformal contact to enhance the overall piezoelectric performance. In addition, we enhanced the piezoelectric properties of 2D WS2 by carrying out a unique solvent-vapor annealing process to produce a sulfur-deficient WS2(1-x) structure that yielded a 3-fold higher piezoelectric response voltage (96.74 mV) than did pristine WS2 to a 3 kPa compression. Our device was also found to be stable: it retained its piezoelectric performance even after a month in an ambient atmospheric condition. Our study has revealed a facile methodology for fabricating large-scale piezoelectric devices using an asymmetrically engineered 2D WS2 structure.