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The oscillating hydrofoil, a device used for collecting environmentally friendly tidal energy, is the focus of the study. The flexibility of the hydrofoil's trailing edge can impact its surface pressure distribution, lift, and moment characteristics. To improve the energy harvesting performance of oscillating hydrofoils, it is important to conduct thorough research on their energy harvesting mechanism. Therefore, numerical analysis is employed to develop a numerical model of the fully passive oscillating hydrofoil with the flexible trailing edge. The dynamic development behavior of surface vortices on hydrofoils is analyzed, demonstrating that the fluid–structure interaction between the hydrofoil and the surrounding fluid alters the hydrofoil's motion. The vortex patterns and pressure distribution on the hydrofoil surface are also affected, ultimately influencing the energy harvesting performance. By optimizing the flexibility coefficient of the fully passive oscillating hydrofoil with a flexible trailing edge, the energy harvesting performance of the oscillating hydrofoil is improved. When the maximum chord offset δm= 0.1c and the flexibility coefficient n = 2, the energy harvesting efficiency is 31.37%, and the average power coefficient is 1.17. Therefore, increasing the tail flexibility can be considered to enhance energy harvesting performance when designing the fully passive oscillating hydrofoil. The research provides a comprehensive analysis of energy harvesting performance, addressing the dynamic problem of the fully passive oscillating hydrofoils with flexible trailing edges. The findings of this study may provide guidance for the design and optimization of tidal energy harvesting devices with similar structures. [ABSTRACT FROM AUTHOR]

Pheochromocytomas and paragangliomas (PPGLs) are a group of rare neuroendocrine tumors. Dysglycemia has been observed in patients with PPGLs in some small case series. However, there is limited information available on the factors associated with development and resolution of dysglycemia in these patients. The clinical data of consecutive patients admitted to our hospital with PPGLs between January 2018 and June 2020 were retrospectively analyzed. Clinical characteristics were compared between patients with and without dysglycemia. Logistic regression analysis was used to identify risk factors and receiver-operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of the variables. Among 163 patients, 58.9% had preoperative dysglycemia. Patients with dysglycemia were significantly older at diagnosis (p = 0.01) and were significantly more likely to have hypertension (p = 0.007). White blood cell counts (p = 0.016), 24-hour urinary epinephrine (24hU-E) levels (p < 0.001) and 24-hour urinary norepinethrine levels (p = 0.008) were significantly higher in patients with dysglycemia. Regression analysis showed that age (odds ratio [OR] 1.028, 95% confidence interval [CI] 1.001–1.055; p = 0.041), hypertension (OR 2.164, 95% CI 1.014–4.619; p = 0.046) and the 24hU-E concentration (OR 1.010, 95% CI, 1.001–1.019; p = 0.025) were positively associated with preoperative dysglycemia. Taking age, hypertension, and 24hU-E into account in the same model, the area under the ROC curve for prediction of preoperative dysglycemia was 0.703. The proportion of patients with dysglycemia decreased significantly after surgery (p < 0.001) and patients with preoperative dyssglycemia that resolved after surgery tended to have a larger preoperative tumor diameter (p = 0.018). Age, hypertension, and the 24hU-E concentration are risk factors for preoperative dysglycemia. Removal of PPGLs can improve dysglycemia in most patients, and postoperative remission of dysglycemia is associated with the preoperative tumor diameter. These results are important for risk assessment and for selecting optimal therapies in patients with dysglycemia in PPGLs. There have been insufficient data to identify factors associated with development and resolution of dysglycemia in patients with PPGLs. Our results show that approximately half of the patients with PPGLs develop dysglycemia; age, hypertension, and the 24hU-E concentration are risk factors for preoperative dysglycemia. Removal of the PPGLs improves dysglycemia in a majority of patients, and a large preoperative tumor diameter is associated with remission of dysglycemia after surgery. [ABSTRACT FROM AUTHOR]

Wireless power transmission (WPT) for a capsule robot (CR) has always been a challenging issue because the unpredictable CR attitude can destabilize the induced power of the receiving coil onboard the CR. This article proposes a new WPT system for stably powering the CR, and it mainly consists of a rotatable two-dimensional transmitting coil (R2DTC), a one-dimensional receiving coil (1DRC), and an attitude detection module (ADM). The R2DTC can excite a uniform and directional alternating magnetic field (AMF) covering the CR workspace, and the AMF amplitude and direction are controllable in the 3-D space. The 1DRC has a shape of thin-walled ring, for ease of being used as a CR outer shell. The ADM is fixed together with the 1DRC; it can detect the 1DRC attitude in real time and is implemented in a compact size. Referring to the 1DRC attitude, the R2DTC can regulate the AMF to stabilize the 1DRC induced power. This article presents design and implementation details of the WPT system, as well as experiments for its performance evaluation. The R2DTC is verified to supply stable power of 500 mW to the attitude-changing 1DRC at most cases, with a transfer efficiency ranging from 8.15% to 13.53%. [ABSTRACT FROM AUTHOR]

Circulating exosomes delivering microRNAs are involved in the occurrence and development of cardiovascular diseases. How are the circulating exosomes involved in the repair of endothelial injury in acute myocardial infarction (AMI) convalescence (3‐7 days) was still not clear. In this study, circulating exosomes from AMI patients (AMI‐Exo) and healthy controls (Normal‐Exo) were extracted. In vitro and in vivo, our study showed that circulating exosomes protected endothelial cells (HUVECs) from oxidative stress damage; meanwhile, Normal‐Exo showed better protective effects. Through the application of related inhibitors, we found that circulating exosomes shuttled between HUVECs via dynamin. Microarry analysis and qRT‐PCR of circulating exosomes showed higher expression of miR‐193a‐5p in Normal‐Exo. Our study showed that miR‐193a‐5p was the key factor on protecting endothelial cells in vitro and in vivo. Bioinformatics analyses found that activin A receptor type I (ACVR1) was the potential downstream target of miR‐193a‐5p, which was confirmed by ACVR1 expression and dual‐luciferase report. Inhibitor of ACVR1 showed similar protective effects as miR‐193a‐5p. While overexpression of ACVR1 could attenuate protective effects of miR‐193a‐5p. To sum up, these findings suggest that circulating exosomes could shuttle between cells through dynamin and deliver miR‐193a‐5p to protect endothelial cells from oxidative stress damage via ACVR1. [ABSTRACT FROM AUTHOR]

A clamper-based capsule robot (CCR) capable of exploring a compliant tube is promising for a minimally invasive medical application. It is composed of a locomotion unit and some functional modules (e.g., camera and telemetry circuit) at both ends; and the locomotion unit consists of a linear mechanism, a fixed clamper, and a free clamper that can be linearly moved by the linear mechanism. For the CCR design and optimization, analyzing the interaction between the CCR and the compliant tube is necessary. For this reason, this article conducts a quantitative locomotion analysis of the CCR in the compliant tube. Based on a minimum displacement assumption and by analyzing the tube deformation induced by each CCR locomotion gait, a model correlating the CCR locomotion efficiency with it design parameters was built. Then, the correctness of the model was validated in an intestine-constructed compliant tube. With the validated model, the influence of the design parameters on the CCR locomotion efficiency was analyzed to derive the design rules. In addition, a quantitative comparison between the locomotion efficiencies of the CCR and a previously developed inchworm-like capsule robot was conducted, showing that the CCR can enable a more efficient exploration for the compliant tube. [ABSTRACT FROM AUTHOR]