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In order to reduce the temperature effects on the testing accuracy of the silicon-on-sapphire high-temperature large-range pressure sensor, a miniaturized portable silicon-on-sapphire pressure sensor temperature compensation system is designed and implemented after solving the following three issues: temperature compensation structure design, temperature compensation circuit fabrication, and temperature compensation algorithm implementation. The simulation results indicated that the temperature of the test circuit part of the package structure is close to 30 °C at an ambient temperature of 30 °C, with the sensor sensitive element at 250 °C working temperature and 28 MPa ultimate pressure. Regarding to the problem of large sensor drift in high-temperature environments, a temperature compensation algorithm combining least squares and Lagrange interpolation is designed based on the input and output characteristics of the sensor. The algorithm improves the computational efficiency while also increasing the hysteresis error and nonlinear deviation of the sensor to 0.028%. The test results of the NIM (National Institute of Metrology, China) show that the measurement accuracy of the sensor is higher than 1 ‰ FS within −20 °C to 140 °C and higher than 3 ‰ FS within 140 °C to 250 °C. • This design comprehensively includes temperature compensation circuitry, temperature compensation algorithms, and the sensor package housing. • The design enables temperature compensation in high-temperature environments, with operating temperatures from −20 °C to 250 °C and a pressure range of 28 MPa. • Designed a test circuit with low thermal noise and high-efficiency suppression of thermal drift based on PGA900. • The temperature compensation algorithm uses a combination of least squares and Lagrange interpolation. [ABSTRACT FROM AUTHOR]

Abstract: The spectral radius of a graph G is the largest eigenvalue of its adjacency matrix. Let denote a book with k pages. In this paper, we generalize a result of Lu et al [M. Lu, H. Liu, F. Tian, A new upper bound for the spectral radius of graphs with girth at least 5, Linear Algebra Appl. 414 (2006) 512–516.] on the upper bound for the spectral radius of connected graphs with girth at least 5 to connected -free graphs G of order with maximum degree as follows:with equality if and only if G is a strongly regular graph with parameters . This implies sharp upper bounds for book-free or -free graphs. [Copyright &y& Elsevier]

Caesium tungsten bronze materials are widely used in various applications, such as architectural glass, medicine, insulation coating and textile fibre, owing to their excellent mechanical, optical and thermal properties. In this study, a caesium tungsten bronze (Cs x WO 3 , x = 0.3–0.32) target with a relative density of 99.63 % and uniform microstructure was successfully prepared via hot-pressing sintering. Cs x WO 3 films were deposited on a quartz glass substrate via magnetron sputtering, and the mechanisms and effects of the substrate temperature and oxygen flow rate on the phase structure, microstructure and optical properties of Cs x WO 3 films were investigated. When the substrate temperature increased, the crystallinity and oxygen vacancy concentration of the Cs x WO 3 film improved. Consequently, the visible light transmittance of the film decreased, whereas the infrared blocking rate considerably increased, reaching up to 93.877 %. With the increase in the oxygen flow rate, the visible light transmittance exhibited an increasing trend, reaching a maximum value of 84.319 %, whereas the infrared blocking rate remained relatively stable. We successfully fabricated Cs x WO 3 films possessing a visible light transmittance of 66 % and infrared blocking rate of 94.97 % under the conditions of a substrate temperature of 300 °C and an oxygen flow rate of 2.5 sccm. Our study offers a method for the large-scale production of Cs x WO 3 films, which are excellent infrared shielding materials, rendering a substantial contribution to global energy conservation and emission reduction. [ABSTRACT FROM AUTHOR]

• An omnidirectional imaging sensor based on conical mirror is designed. • The optical path of the sensor is analyzed. • The basic criteria for determining parameters of the sensor is proposed. • A new image unwrapping method is proposed. • Defect on the inner surface of pipelines can be detected correctly. As a sensor carrier and directional constraint equipment, precision pipelines are prone to significant damage to the inner surface over time, posing safety hazards. To implement the inspection of the pipeline's inner surface, an omnidirectional imaging sensor based on a conical mirror and single camera was designed in this paper. The optical imaging model of the sensor was constructed to analyze the field-of-view (FOV) and depth-of-field (DOF) of the sensor, and the parameters of the sensor's structure were determined. Then, a concentric circle unwrapping method based on secondary correction was proposed to correct the distortion of panoramic images. Additionally, the position of the conical mirror was calibrated to rectify the assembly error. Finally, unwrapped images and YOLOv8 were utilized to implement the detection of the defects, such as scratches and pits, on the inner surface of pipelines. The experiments showed that the accuracy of defect detection was approximately 80.1%. The omnidirectional imaging sensor designed in this paper was capable of imaging the inner surface of pipelines, which was used for detecting and classifying the surface defects. [ABSTRACT FROM AUTHOR]

Proposed mechanism of Marein. Marein treatment improved diabetic nephropathy by inhibiting SGLT2 and activating the AMPK signaling pathway. Furthermore, Marein ameliorated fibrosis and inflammation by suppressing IL-6, MCP-1, FN and COL1. • Marein decreased renal ectopic lipid deposition by inhibiting SGLT2 and activating the AMPK/ACC/PGC-1α pathway in db/db mice. • Marein ameliorated metabolic dysfunction by inhibiting SGLT2 and activating AMPK in high glucose-treated HK-2 cells. • Marein ameliorated fibrosis and inflammation by suppressing FN, COL1, IL-6 and MCP-1. Marein, an active component of the Coreopsis tinctoria Nutt. plant, is known to improve diabetic nephropathy (DN). However, its anti-diabetic functions in DN and potential mechanisms remain unclear. The aim of this study was to elucidate the effects and mechanisms of Marein in diabetic db/db mice with DN, and in high glucose–treated HK-2 cells. In vivo , treating diabetic db/db mice with Marein for 12 consecutive weeks restored diabetes-induced hyperglycemia and dyslipidemia, and ameliorated renal function deterioration, glomerulosclerosis, and renal ectopic lipid deposition. Marein exerted renoprotective effects by directly inhibiting renal tubule sodium glucose transporter 2 (SGLT2) expression, and then activating the AMP-activated protein kinase (AMPK)/acetyl CoA carboxylase (ACC)/peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) pathway in db/db mice. Meanwhile, Marein ameliorated fibrosis and inflammation by suppressing the pro-inflammatory factors interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1), and expression of the extracellular matrix proteins, fibronectin (FN) and collagen 1 (COL1) in diabetic mice. In vitro , MDCK monolayer cells were established to explore the characteristics of Marein transmembrane transport. Marein was found to be absorbed across the membrane at a medium level that involved active transport and this was mediated by SGLTs. In HK-2 cells, Marein decreased uptake of the fluorescent glucose analog, 2-NBDG, by 22 % by inhibiting SGLT2 expression. In high glucose–treated HK-2 cells, Marein decreased SGLT2 expression and increased phosphorylated (p)-AMPK/p-ACC to improve high glucose–induced cellular dysfunction. Furthermore, Marein treatment decreased SGLT2 expression in SGLT2-overexpressing HK-2 cells. In addition, molecular docking and dynamics analysis revealed that SGLT2 was a direct target of Marein. Collectively, our results demonstrated that Marein ameliorates DN by inhibiting renal SGLT2 and activating p-AMPK, suggesting Marein can potentially prevent DN by suppressing renal SGLT2 expression directly. [ABSTRACT FROM AUTHOR]