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There are many cases of biliary stent migration. Generally, biliary stent migrates distally. While, biliary stent rarely migrates proximally. Here we reported the case of a 49-year-old woman who underwent robot assisted right hemihepatectomy, and placement of a biliary stent for complicating bile leakage. The patient was discharged from hospital after recovering from bile leakage. Five months later, a follow-up examination revealed that the biliary stent had shifted into the liver, leading to liver perforation. We fully removed the stent by using a stone retrieval balloon and a snare. We suggested that when useing a biliary stent, it is necessary to consider of appropriate length of the stent and inform the patient when to return to the hospital for stent removal, in order to avoid stent migration and complications occurrence.

Composite roll produced through casting methods typically remain in the as-cast state after forming. During the preparation process, extended exposure to high temperatures often results in microstructural coarsening at the interface and surface layers, restricting their mechanical performance. To overcome this limitation, we developed a novel vacuum billet forging process for the fabrication of composite rolls. By integrating numerical simulations with experimental validation, we successfully prepared a 42CrMo/Cr5 composite roll. The comprehensive characterization of the interface, including microstructure, elemental distribution, grain texture, grain type, and mechanical properties, was conducted using OM, SEM, EPMA, EBSD, Vickers hardness testing, and a universal testing machine. The relationship between the interface microstructure and mechanical performance was systematically analyzed. The results indicate that complete metallurgical bonding at the interface was achieved with an upsetting reduction ratio of 40% and a single-pass elongation reduction ratio of less than 10%. The interfacial microstructure consisted of four zones: the roll core exhibited lamellar pearlite and blocky ferrite; the diffusion layer near 42CrMo featured pearlite; the diffusion layer near Cr5 contained pearlite and Cr carbides; the Cr5 layer contained fine lamellar pearlite with a greater amount of dispersed Cr carbides. Significant diffusion of Cr and Ni elements was observed, with Cr diffusion extending to 70–90 μm. The interface grains experienced substantial deformation and recrystallization, enhancing the bonding strength. Tensile tests indicated that fracture occurred on the 42CrMo side, with yield and tensile strengths of 371 MPa and 729 MPa, respectively. The microhardness of the composite interface gradually increased from 190 HV to 305 HV without abrupt changes. A significant hardness difference was observed on both sides of the interface, while the variation within the diffusion layer was relatively smooth, indicating good bonding performance at the composite interface. [ABSTRACT FROM AUTHOR]

Precision medicine provides a holistic perspective of an individual’s health, including genetic, environmental, and lifestyle aspects to realize individualized therapy. The development of the internet of things (IoT) devices, the widespread emergence of electronic medical records (EMR), and the rapid progress of cloud computing and artificial intelligence provide an opportunity to collect healthcare big data throughout the lifespan and analyze the disease risk at all stages of life. Thus, the focus of precision medicine is shifting from treatment toward prediction and prevention, i.e., precision health. To this end, various types of data such as omics, imaging, EMR, continuous physiological monitoring, lifestyle, and environmental information, need to be collected, tracked, managed and shared. Thus, internet-of-medical things (IoMT) is crucial for assimilating the health systems, applications, services, and devices that can improve the speed and accuracy of diagnosis and treatments along with real-time monitoring and modification of patient behavior as well as health status. However, security has emerged as a growing concern owing to the proliferation of IoMT devices. The increasing interconnectivity of IoMT-enabled devices with health data reception, transmission, and processing significantly increases the number of potential vulnerabilities within a system. To address the security issues of precision health in IoMT systems, this study reviews the state-of-the-art techniques and schemes from the perspective of a hierarchical system architecture. We present an IoMT system model comprising three layers: the sensing layer, network layer, and cloud infrastructure layer. In particular, we discuss the vulnerabilities and threats to security in each layer and review the existing security techniques and schemes corresponding to the system components along with their functionalities. Owing to the unique nature of biometric features in medical and health services, we highlight the biometrics-based technologies applied in IoMT systems, which contribute toward a considerable difference between the security solutions of existing IoT systems. Furthermore, we summarize the challenges and future research directions of IoMT systems to ensure an improved and more secure future of precision health.

Pancreatic ductal adenocarcinoma (PDAC) is a rapidly progressing malignancy with a poor prognosis. Quercetin is a flavonoid compound with various biological benefits that can be extracted from Chinese herbs or daily foods. Quercetin has anticancer properties in various types of cancers. However, its therapeutic effects and potential mechanisms in PDAC have not been investigated extensively. Here, we confirmed the therapeutic effect of quercetin in PDAC using a mouse model. Based on high‐throughput RNA sequencing (RNA‐seq) and bioinformatic analysis, we propose that quercetin is involved in stromal infiltration of PDAC. Quercetin attenuates the activation of cancer‐associated fibroblasts (CAFs) via tumor‐stromal interaction. Meanwhile, we have identified two quercetin‐related prognostic models for patients with PDAC. Finally, we proposed a downstream target of quercetin, the ITGB4 gene, which could be a potential therapeutic target for PDAC. [ABSTRACT FROM AUTHOR]

Traveling wave rotary ultrasonic motors (TRUSMs) have been applied in optical systems, robotics, biomedical and other fields. However, the disadvantages such as short working life, driving performance degradation, and low energy utilization significantly limit the long-term and stable operation of TRUSMs in advanced fields like aerospace mechanisms. To address the above issues, a novel rotary ultrasonic motor based on multiple Langevin transducers is proposed in this paper. First, the structural design, driving principle and general design criteria are described in detail. Then, the structural parameters are optimized by finite element simulation analysis. Second, a prototype is assembled controllably. Subsequently, the impedance test and vibration measurement are carried out. The results show that the traveling wave is successfully generated on the tooth-ring, and all the Langevin transducers are excited to the first-order longitudinal vibration modes, which strongly verify the correctness of design principle. Finally, the driving performance experiment is carried out. The experimental results show that the no-load speed is 62 r min−1 under the pre-pressure of 10 N. The stalling torque is 0.94 N m at the driving voltage of 500 Vp-p. The response characteristics show that the start/stop time are 4.6/5.5 ms, and the angular displacement resolution of clockwise/counterclockwise driving are 6.7/10.2 μ rad. The motor proposed in this paper not only exhibits relatively high output performance with excellent vibration characteristics, but also maintains compactness of the structure. The sandwiched structure design effectively avoids the problem that the bonded-type piezoceramic rings in conventional TRUSMs are prone to damage or fall-off when vibrating for a long time. Furthermore, the general design criteria provide a new approach to develop high performance rotary ultrasonic motors. The proposed novel ultrasonic motor is expected to meet the demand for long-term and stable operation in aerospace mechanisms. [ABSTRACT FROM AUTHOR]