Dual-Use Strain Sensors for Acoustic Emission and Quasi-Static Bending Measurements.

In this paper, a MEMS piezoresistive ultrathin silicon membrane-based strain sensor is presented. The sensor's ability to capture an acoustic emission signal is demonstrated using a Hsu-Nielsen source, and shows comparable frequency content to a commercial piezoceramic ultrasonic transducer. To the authors' knowledge, this makes the developed sensor the first known piezoresistive strain sensor which is capable of recording low-energy acoustic emissions. The improvements to the nondestructive evaluation and structural health monitoring arise from the sensor's low minimum detectable strain and wide-frequency bandwidth, which are generated from the improved fabrication process that permits crystalline semiconductor membranes and advanced polymers to be co-processed, thus enabling a dual-use application of both acoustic emission and static strain sensing. The sensor's ability to document quasi-static bending is also demonstrated and compared with an ultrasonic transducer, which provides no significant response. This dual-use application is proposed to effectively combine the uses of both strain and ultrasonic transducer sensor types within one sensor, making it a novel and useful method for nondestructive evaluations. The potential benefits include an enhanced sensitivity, a reduced sensor size, a lower cost, and a reduced instrumentation complexity.

Pomegranate juice-containing serum inhibits migration of hepatocellular carcinoma cells and promotes apoptosis by induction of mitochondrial dysfunction.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide, with an insidious onset and poor prognosis. Pomegranate is a fruit rich in many natural products with anti-cancer potential; however, its direct biological effects are difficult to evaluate in vitro because of changes in its active components after absorption and metabolism. This study was conducted to prepare pomegranate juice-containing serum (PJ serum) by gavage of pomegranate juice (PJ) in rats and to collect serum. The aim was to investigate the components and the effects of PJ serum on HCC cells by serum pharmacology. 56 compounds were identified in the PJ serum, including 6 prototype components. PJ serum selectively inhibited HCC cells proliferation and migration, and it promoted apoptosis of HCC cells without affecting LO2 cells activity. Furthermore, PJ serum reduced the mitochondrial membrane potential and increased the calcium ion concentration in HCC cells. Mechanistically, PJ serum up-regulated the expression of the Bax family, Caspases and TIMP2/MMP2, and down-regulated the expression of MMP9. This study revealed that PJ serum inhibited HCC cell migration by regulating the TIMP2/MMP2 balance and MMP9 expression and promoted HCC cell apoptosis by inducing mitochondrial dysfunction and causing a Caspase cascade. The polyphenols and flavonoids in PJ may be important components responsible for its anti-HCC activity after metabolism.

Rosa Roxburghii Tratt Fruit Extract Prevents Dss-Induced Ulcerative Colitis in Mice by Modulating the Gut Microbiota and the IL-17 Signaling Pathway.

Ulcerative colitis (UC) is a non-specific inflammatory bowel illness characterized by intestinal mucosal barrier degradation, inflammation, oxidative damage, and gut microbiota imbalances. Rosa roxburghii Tratt Fruit extract (RRTE) was extracted from Rosa roxburghii Tratt fruit, exhibiting an excellent prevention effect against UC; RRTE could prevent the damage of DSS-induced human normal colonic epithelial (NCM 460) cells, especially in cell viability and morphology, and oxidative damage. Additionally, in UC mice, RRTE could limit the intestinal mucosal barrier by increasing the expression of intestinal tight junction proteins and mucin, reducing inflammation and oxidative damage in colon tissue. More importantly, RRTE can increase the abundance of beneficial bacteria to regulate gut microbiota such as Ruminococcus, Turicibacter, and Parabacteroides, and reduce the abundance of harmful bacteria such as Staphylococcus and Shigella. Furthermore, transcriptomics of colonic mucosal findings point out that the beneficial effect of RRTE on UC could be attributed to the modulation of inflammatory responses such as the IL-17 and TNF signaling pathways. The qPCR results confirm that RRTE did involve the regulation of several genes in the IL-17 signaling pathway. In conclusion, RRTE could prevent DSS-induced damage both in vitro and in vivo.

Effects of Rosa roxburghii Tratt on Ulcerative Colitis: An Integrated Analysis of Network Pharmacology and Experimental Validation.

Rosa roxburghii Tratt is a traditional Chinese plant that has been used to treat different inflammatory diseases. The purpose of this study was to investigate the mechanism of action of Rosa roxburghii Tratt extract (RRTE) against ulcerative colitis (UC) using network pharmacology and experimental validation. HPLC-Q/Orbitrap MS was used to rapidly identify the substances contained in RRTE after extracting the active components from the fruit. Then, network pharmacology combined with molecular docking was used to explore the critical target and potential mechanism of RRTE against UC using the active ingredients in RRTE as the research object. Data are presented in a visual manner. Finally, the pharmacological effects of RRTE in alleviating UC were further verified using a DSS-induced UC model of NCM460. The results showed that 25 components in RRTE were identified. A total of 250 targets of the active components and 5376 targets associated with UC were collected. Furthermore, a systematic analysis of the Protein-Protein Interaction (PPI) networks suggests that epidermal growth factor receptor (EGFR), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), and serine/threonine kinase 1 (AKT1) are critical targets for RRTE in the treatment of UC. A comprehensive regulatory network analysis showed that RRTE alleviated UC through the EGFR-mediated PI3K/Akt pathway, and molecular docking showed that active components could strongly bind to EGFR, PIK3R1, and AKT1. In addition, RRTE alleviated dextran sulfate sodium salt (DSS)-induced cell injury and significantly decreased the protein expression levels of EGFR, PIK3R1, and p-AKT in NCM460 cells in vitro. Furthermore, RRTE significantly regulated the expression of the apoptosis-related proteins Apoptotic protease-activating factor 1 (Apaf1), cleaved caspase-3, B-cell lymphoma-2 (Bcl2), and Bcl2 associated X protein (Bax). In conclusion, the components of RRTE are complex, and RRTE can relieve UC through the EGFR-mediated PI3K/Akt pathway.

Development of a Flexible Integrated Self-Calibrating MEMS Pressure Sensor Using a Liquid-to-Vapor Phase Change.

Self-calibration capabilities for flexible pressure sensors are greatly needed for fluid dynamic analysis, structure health monitoring and wearable sensing applications to compensate, in situ and in real time, for sensor drifts, nonlinearity effects, and hysteresis. Currently, very few self-calibrating pressure sensors can be found in the literature, let alone in flexible formats. This paper presents a flexible self-calibrating pressure sensor fabricated from a silicon-on-insulator wafer and bonded on a polyimide substrate. The sensor chip is made of four piezoresistors arranged in a Wheatstone bridge configuration on a pressure-sensitive membrane, integrated with a gold thin film-based reference cavity heater, and two thermistors. With a liquid-to-vapor thermopneumatic actuation system, the sensor can create precise in-cavity pressure for self-calibration. Compared with the previous work related to the single-phase air-only counterpart, testing of this two-phase sensor demonstrated that adding the water liquid-to-vapor phase change can improve the effective range of self-calibration from 3 psi to 9.5 psi without increasing the power consumption of the cavity micro-heater. The calibration time can be further improved to a few seconds with a pulsed heating power.

N/O Co-doped Porous Carbons Derived from Coal Tar Pitch for Ultra-high Specific Capacitance Supercapacitors.

In this paper, a series of N/O co-doped porous carbons (PCs) were designed and used to prepare coal tar pitch-based supercapacitors (SCs). The introduction of N/O species under the intervention of urea effectively improves the pseudocapacitance of PCs. The results show that the specific surface area of synthesized N3PC4-700 is 1914 m2 g-1, while the N and O contents are 1.3 and 7.2%, respectively. The unique interconnected pore structure and proper organic N/O co-doping, especially the introduction of pyridine-N and pyrrole-N, are beneficial for improving the electrochemical performance of PCs. In the three-electrode system, the specific capacitance and rate capability of N3PC4-700 are 532.5 F g-1 and 72.5% at the current densities of 0.5 and 20 A g-1, respectively. In addition, the specific capacitance of N3PC4-700 in a coin-type symmetric device is 315.5 F g-1 at 0.5 A g-1. The N3PC4-700 electrode provides an energy density of 43.8 W h kg-1 with a power density of 0.5 kW kg-1 and still maintains a value of 29.7 at 10 kW kg-1. After 10,000 charge/discharge cycles, the retention rate was as high as 96.7%. In order to obtain high-performance carbon-based SCs, the effective identification and regulation of organic N/O species is necessary.

Numerical Study of the Thermal Performance of a Mems Pressure Sensor with Self-Calibration Capabilities.

Recent industry trends toward more complex and interconnected systems have increased the demand for more reliable pressure sensors. By integrating a microactuator with a pressure sensor, the sensor can self-calibrate, eliminating the complexities and costs associated with traditional sensor calibration methods to ensure reliability. The present work is focused on furthering understanding and improving the thermal performance of a thermopneumatic actuated self-calibrating pressure sensor. A transient numerical model was developed in ANSYS and was calibrated using experimental testing data. The numerical model provided insights into the sensor's performance not previously observed in experimental testing. Furthermore, the model was utilized for two design studies. First, it was found that a substrate with low thermal conductivity and high thermal diffusivity is ideal for both the sensor's efficiency and a faster transient response time. The second design study showed that decreasing the size of the sealed reference cavity lowers power consumption and transient response time. The study also showed that reducing the cavity base dimension has a greater effect on lowering power consumption and response time. Overall, the present work increases understanding of the self-calibrating pressure sensor and provides insight into potential design improvements, moving closer to optimized self-calibrating pressure sensors.

Solvothermal Synthesis of Sphere-Like ZnS Microparticles and Its Visible-Light Catalytic Properties.

The cauliflower-like ZnS microspheres consisting of the nanospheres were prepared via one step template-free approach employing a solvothermal process using Zn(NO3)2·6H2O and CH4N2S as precursors in the mixture solution. The morphology, structure characterization, and crystal structure of the as-prepared ZnS were performed by X-ray diffraction, scanning electron microscopy, UV-visible absorption, and X-ray photoelectron spectroscopy. The results showed that cauliflowerlike ZnS microspheres were prepared under this condition and the size of the particles were about 3~5 µm. In addition, the excellent photocatalytic activity and degradation mechanism of ZnS microspheres have been investigated and discussed in detail. The degradation of Rhodamine B (RhB) aqueous solution was carried out to investigate the visible-light catalytic activity under metal halide lamp. The results indicated that different size of ZnS had photocatalytic activity to RhB under visible light, and sphere-like ZnS displayed high photodegradation efficiency with degradation rate of 98% within 140 min.

Observation of Quantized and Partial Quantized Conductance in Polymer-Suspended Graphene Nanoplatelets.

Quantized conductance is observed at zero magnetic field and room temperature in metal-insulator-metal structures with graphene submicron-sized nanoplatelets embedded in a 3-hexylthiophene (P3HT) polymer layer. In devices with medium concentration of graphene platelets, integer multiples of G o = 2e (2)/h (=12.91 kΩ(-1)), and in some devices partially quantized including a series of with (n/7) × G o, steps are observed. Such an organic memory device exhibits reliable memory operation with an on/off ratio of more than 10. We attribute the quantized conductance to the existence of a 1-D electron waveguide along the conductive path. The partial quantized conductance results likely from imperfect transmission coefficient due to impedance mismatch of the first waveguide modes.