Quercetin is the most abundant flavonoid and is assumed to have protective roles against the pathogenesis of multiple diseases associated with oxidative stress. In the present study, we investigated ...the molecular mechanisms by which quercetin affects adipogenesis and apoptosis in 3T3-L1 cells. The exposure of 3T3-L1 preadipocytes to quercetin resulted in attenuated adipogenesis and decreased expression of adipogenesis-related factors and enzymes. Moreover, quercetin exposure up-regulated the levels of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylase (ACC). Treatment of 3T3-L1 adipocytes with quercetin resulted in the induction of apoptosis and a concomitant decrease in ERK and JNK phosphorylation. Taken together, these data indicate that quercetin exerts anti-adipogenesis activity by activating the AMPK signal pathway in 3T3-L1 preadipocytes, while the quercetin-induced apoptosis of mature adipocytes was mediated by modulation of the ERK and JNK pathways, which play pivotal roles during apoptosis.
Hierarchical structures allow one to improve device performance by exploiting the synergistic effects of micro/nano multiscale components. However, the structural complexity of hierarchical ...structures places limits on their fabrication and applications. Herein, a novel morphology-controllable wrinkled micro/nano hierarchical structure (WHS) was developed by integrating micropatterns, nanopatterns, and wrinkles on a single substrate to overcome these limitations. Each structure could be individually controlled, which offers unlimited design diversity. The produced WHS was used as a superhydrophobic triboelectric nanogenerator. Compared to a nanogenerator with on a film structure, the WHS-based nanogenerator showed a superior contact angle of 152.5°, which is indicative of high hydrophobicity, and an enhanced (by 608%) triboelectric effect, which was ascribed to the highly rough surface of the WHS. The WHS-based nanogenerator was used to fabricate a self-powered and water-repellent cough detection sensor with an entirely superhydrophobic structure and stable superior sensing performance during repeated water spraying.
This study describes a novel fabrication method of hierarchical structures, which can integrate micropatterns, nanopatterns, and wrinkles on a single substrate. This method allows one to independently control three different structures and thus fabricate the wrinkled micro/nano hierarchical structures (WHS). The WHS is utilized as a self-powered and water-repellent cough detection sensor that maintains detection performance during repeated water spraying. Display omitted
•A novel fabrication method for wrinkled hierarchical structures (WHSs) is described.•Micropatterns, nanopatterns, and wrinkles can be integrated on a single substrate.•WHSs is utilized as a superhydrophobic triboelectric nanogenerator (S-TENG).•We demonstrate S-TENG as self-powered and water-repellent cough detection sensors.•The sensor maintains superior detection performance during repeated water spraying.
A medical tool is a general instrument intended for use in the prevention, diagnosis, and treatment of diseases in humans or other animals. Nowadays, sensors are widely employed in medical tools to ...analyze or quantify disease‐related parameters for the diagnosis and monitoring of patients’ diseases. Recent explosive advancements in sensor technologies have extended the integration and application of sensors in medical tools by providing more versatile in vivo sensing capabilities. These unique sensing capabilities, especially for medical tools for surgery or medical treatment, are getting more attention owing to the rapid growth of minimally invasive surgery. In this review, recent advancements in sensor‐integrated medical tools are presented, and their necessity, use, and examples are comprehensively introduced. Specifically, medical tools often utilized for medical surgery or treatment, for example, medical needles, catheters, robotic surgery, sutures, endoscopes, and tubes, are covered, and in‐depth discussions about the working mechanism used for each sensor‐integrated medical tool are provided.
In this review, recent advancements in sensor‐integrated medical tools are presented, and their necessity, use, and examples are comprehensively introduced. Specifically, medical tools often utilized for medical surgery or treatment, for example, medical needles, catheters, robotic surgery, sutures, endoscopes, and tubes, are covered, and in‐depth discussions about the working mechanism of each sensor‐integrated medical tool are provided.
Due to its ease of use and flexibility, the robot operating system (ROS) is increasingly becoming the most popular middleware for robot applications, even in multiagent systems. Since ROS 1.0 does ...not satisfy real-time requirements, ROS 2.0 was developed, and it improved the communication stack with the real-time data distribution service (DDS) protocol. However, the actual performance level to be expected is still unknown and can largely depend on the operating system and the kernel being used, the DDS distribution, and the overall software load of the system. In this paper, we present an empirical study that evaluates the real-time performance of ROS 2.0 in both the system and communication software layers. In the system layer, the deterministic behavior of the ROS 2.0 nodes is thoroughly observed with regard to whether the tasks are schedulable and can function within the specified temporal deadline. In the communication layer, special attention is devoted to the rate of data loss and the overall latency of messages between nodes. Experiments are performed in various working conditions; for example, the system load is increased to define the real-time performance of the tasks. For reference, the results are compared with the those from the traditional ROS variation. Moreover, we implement a multiagent service robot system to verify the suitability of ROS 2.0 for real-world applications. Our results show that the application of ROS 2.0 is more suitable than that of ROS 1.0 in terms of real-time performance.
In order to realize a transition from conventional to stretchable electronics, it is necessary to make a universal stretchable circuit board in which passive/active components can be robustly ...integrated. We developed a stretchable printed circuit board (s-PCB) platform that enables easy and reliable integration of various electronic components by utilizing a modulus-gradient polymeric substrate, liquid metal amalgam (LMA) circuit traces, and Ag nanowire (AgNW) contact pads. Due to the LMA–AgNW biphasic structure of interconnection, the LMA is hermetically sealed by a homogeneous interface, realizing complete leak-free characteristics. Furthermore, integration reliability is successfully achieved by local strain control of the stretchable substrate with a selective glass fiber reinforcement (GFR). A strain localization derived by GFR makes almost 50,000% of strain difference within the board, and the amount of deformation applied to the constituent elements can be engineered. We finally demonstrated that the proposed integrated platform can be utilized as a universal s-PCB capable of integrating rigid/conventional electronic components and soft material-based functional elements with negligible signal distortion under various mechanical deformations.
The growing demand for complex three-dimensional (3D) micro-/nanostructures has inspired the development of the corresponding manufacturing techniques. Among these techniques, 3D fabrication based on ...mechanically guided assembly offers the advantages of broad material compatibility, high designability, and structural reversibility under strain but is not applicable for nanoscale device printing because of the bottleneck at nanofabrication and design technique. Herein, a configuration-designable nanoscale 3D fabrication is suggested through a robust nanotransfer methodology and design of substrate's mechanical characteristics. Covalent bonding-based two-dimensional nanotransfer allowing for nanostructure printing on elastomer substrates is used to address fabrication problems, while the feasibility of configuration design through the modulation of substrate's mechanical characteristics is examined using analytical calculations and numerical simulations, allowing printing of various 3D nanostructures. The printed nanostructures exhibit strain-independent electrical properties and are therefore used to fabricate stretchable H
and NO
sensors with high performances stable under external strains of 30%.
In this study, Bi0.5Sb1.5Te3.0 (BST) nanoparticles (NPs) with high crystallinities were synthesized via a mechanochemical process (MCP). X-ray diffraction (XRD), and Raman and X-ray photoelectron ...spectroscopy (XPS) spectra of the BST NPs showed that the Bi, Sb, and Te powders successfully formed BiSbTe phase and transmission electron microscopy (TEM) images, verifying the high crystallinity and smaller size, albeit agglomerated. The as-synthesized BST NPs with agglomerated clusters were ground into smaller sizes of approximately 41.8 nm with uniform distribution through a simple wet-milling process during 7 days. The thermal conduction behaviors of bulk alloys fabricated by spark plasma sintering (SPS) of the BST NPs were studied by comparing those of samples fabricated from as-synthesized BST NPs and a BST ingot. The thermal conductivities (κ) of the BST nanocomposites were significantly reduced by introducing BST NPs with smaller grain sizes and finer distributions in the temperature range from 300 to 500 K. The BST nanocomposites fabricated from wet-milled BST NPs offered ultralow κ values of 0.84 W m−1 K−1 at approximately 398 K.
A radiofrequency ablation (RFA) needle integrated with a temperature sensor (T‐sensor) and pressure sensor (P‐sensor) is designed and utilized for real‐time internal steam pop monitoring during RFA. ...The characteristics of the sensor‐integrated RFA needle (sRFA‐needle) are investigated quantitatively using a pressure chamber system, and the feasibility and usability of the needle in preclinical and clinical trials is demonstrated. The sharp changes in the temperature and normalized pressure sensor signals induced by the abrupt release of hot and high‐pressure steam can be clearly monitored during the steam pop phenomena. The basic mechanism of the preliminary steam pop is hypothesized and verified using in situ ultrasound imaging data and computational analysis data of the RFA procedure. Moreover, the usability of the system in clinical trials is investigated, and the steam pop phenomena during the RFA procedure are detected using T‐sensor and P‐sensor. The results confirm that the sensor integration on the medical needle can provide critical data for safer and more effective medical practices.
A radiofrequency ablation (RFA) needle integrated with a flexible thin‐film type temperature and a pressure sensor is reported and its clinical applications toward real‐time detection of internal steam pop and monitoring of environmental change in the ablation zone are studied. The study is performed in a pre‐clinical trial (animal study) and clinical trial (human study) to verify their usefulness in an in‐vivo environment.
Abstract
Individuals who are unable to walk independently spend most of the day in a wheelchair. This population is at high risk for developing pressure injuries caused by sitting. However, early ...diagnosis and prevention of these injuries still remain challenging. Herein, we introduce battery-free, wireless, multimodal sensors and a movable system for continuous measurement of pressure, temperature, and hydration at skin interfaces. The device design includes a crack-activated pressure sensor with nanoscale encapsulations for enhanced sensitivity, a temperature sensor for measuring skin temperature, and a galvanic skin response sensor for measuring skin hydration levels. The movable system enables power harvesting, and data communication to multiple wireless devices mounted at skin-cushion interfaces of wheelchair users over full body coverage. Experimental evaluations and numerical simulations of the devices, together with clinical trials for wheelchair patients, demonstrate the feasibility and stability of the sensor system for preventing pressure injuries caused by sitting.
Android is gaining popularity as the operating system of embedded systems and recent demands of its application on industrial control are steadily increasing. However, its feasibility is still in ...question due to two major drawbacks: safety and security. In particular, ensuring the safe operation of industrial control systems requires the system to be governed by stringent temporal constraints and should satisfy real-time requirements. In this sense, we explore the real-time characteristics of Xenomai to guarantee strict temporal deadlines, and provide a viable method integrating Android processes to real-time tasks. Security is another issue that affects safety due to the increased connectivity in industrial systems provoking a higher risk of cyber and hardware attacks. Herein, we adopted a hardware copy protection chip and enforced administrative security policies in the booting process and the Android application layer. These policies ensure that the developed system is protected from physical tampering and unwanted Android applications. The articulacy of the administrative policies is demonstrated through experiments. The developed embedded system is connected to an industrial EtherCAT motion device network exhibiting operability on an actual industrial application. Real-time performance was evaluated in terms of schedulability and responsiveness, which are critical in determining the safety and reliability of the control system.
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