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ObjectivesThe mammalian tongue develops from the branchial arches (1-4) and comprises highly organized tissues compartmentalized by mesenchyme/connective tissue that is largely derived from neural crest (NC). This study aimed to understand the roles of tumour suppressor Neurofibromin 2 (Nf2) in NC-derived tongue mesenchyme in regulating Hippo signalling and cell proliferation for the proper development of tongue shape and size.Materials and methodsConditional knockout (cKO) of Nf2 in NC cell lineage was generated using Wnt1-Cre (Wnt1-Cre/Nf2cKO ). Nf2 expression, Hippo signalling activities, cell proliferation and tongue shape and size were thoroughly analysed in different tongue regions and tissue types of Wnt1-Cre/Nf2cKO and Cre- /Nf2fx/fx littermates at various stages (E10.5-E18.5).ResultsIn contrast to many other organs in which the Nf2/Hippo pathway activity restrains growth and cell proliferation and as a result, loss of Nf2 decreases Hippo pathway activity and promotes an enlarged organ development, here we report our observations of distinct, tongue region- and stage-specific alterations of Hippo signalling activity and cell proliferation in Nf2cKO in NC-derived tongue mesenchyme. Compared to Cre- /Nf2fx / fx littermates, Wnt1-Cre/Nf2cKO depicted a non-proportionally enlarged tongue (macroglossia) at E12.5-E13.5 and microglossia at later stages (E15.5-E18.5). Specifically, at E12.5 Nf2cKO mutants had a decreased level of Hippo signalling transcription factor Yes-associated protein (Yap), Yap target genes and cell proliferation anteriorly, while having an increased Yap, Yap target genes and cell proliferation posteriorly, which lead to a tip-pointed and posteriorly widened tongue. At E15.5, loss of Nf2 in the NC lineage resulted in distinct changes in cell proliferation in different regions, that is, high in epithelium and mesenchyme subjacent to the epithelium, and lower in deeper layers of the mesenchyme. At E18.5, cell proliferation was reduced throughout the Nf2cKO tongue.

Volatile organic compounds (VOC) have been proven to cause considerable harm to both the ecological environment and human health. Anthropogenic VOC emissions are primarily generated by the industrial sector. The utilization of porous carbon as an adsorbent has emerged as an effective method for the efficient removal of VOC from industrial sources. However, during the actual production processes, VOC exhaust gases are often mixed with water vapor, which poses challenges for adsorption purification. This review provides a comprehensive overview of the remarkable advancements in various carbon materials in terms of their ability to adsorb both VOC and water vapor. Additionally, it systematically summarizes the influence of surface groups on adsorbents and the molecular properties of VOC on their adsorption by carbon materials. Furthermore, this review introduces the mechanism underlying adsorption-adsorbent interactions and discusses the construction of models for adsorbing water vapor and VOC. The challenges associated with the application of carbon materials for VOC adsorption in humid environments are also addressed. This review aims to offer theoretical and technical guidance for the effective purification of moist VOC waste gases emitted from industrial sources, thereby achieving precise control of VOC emissions. [ABSTRACT FROM AUTHOR]

Due to their high accuracy, excellent stability, minor size, and low cost, silicon piezoresistive pressure sensors are used to monitor downhole pressure under high-temperature, high-pressure conditions. However, due to silicon's temperature sensitivity, high and very varied downhole temperatures cause a significant bias in pressure measurement by the pressure sensor. The temperature coefficients differ from manufacturer to manufacturer and even vary from batch to batch within the same manufacturer. To ensure high accuracy and long-term stability for downhole pressure monitoring at high temperatures, this study proposes a temperature compensation method based on bilinear interpolation for piezoresistive pressure sensors under downhole high-temperature and high-pressure environments. A number of calibrations were performed with high-temperature co-calibration equipment to obtain the individual temperature characteristics of each sensor. Through the calibration, it was found that the output of the tested pressure measurement system is positively linear with pressure at the same temperatures and nearly negatively linear with temperature at the same pressures, which serves as the bias correction for the subsequent bilinear interpolation temperature compensation method. Based on this result, after least squares fitting and interpolating, a bilinear interpolation approach was introduced to compensate for temperature-induced pressure bias, which is easier to implement in a microcontroller (MCU). The test results show that the proposed method significantly improves the overall measurement accuracy of the tested sensor from 21.2% F.S. to 0.1% F.S. In addition, it reduces the MCU computational complexity of the compensation model, meeting the high accuracy demand for downhole pressure monitoring at high temperatures and pressures. [ABSTRACT FROM AUTHOR]

Currently, the focus of stochastic resonance (SR) research is primarily on bistable systems, and classical bistable SR systems have the problems of low dimension, inconvenient parameter adjustment, and high threshold for SR effects. In this paper, based on the classic bistable system, a class of multi-dimensional single potential well SR systems without transition threshold is proposed and applied to signal processing. Firstly, the mechanism of double potential well SR and single potential well SR is studied. On this basis, a kind of multi-dimensional single potential well SR system is defined and its theoretical conditions are analyzed. Then a specific four-dimensional single potential well SR system is constructed, and the dynamics of the system is analyzed. The gain range and the approximate relationship between the system input and the four-dimensional output are derived. Finally, the four-dimensional single potential well SR system is applied to the processing of various signals. The experimental results show that the constructed system has good noise reduction and feature amplification effects on noisy signals through the advantages of multi-dimensional output, and can be used to highlight the fault feature frequency in bearing fault signals. [ABSTRACT FROM AUTHOR]

BackgroundCurrently, the destructive puncture manometry method is used to measure helium pressure inside fuel rods. However, this method is expensive and does not guarantee 100% coverage. Hence the non-destructive testing (NDT) equipment is introduced for non-destructive measurement of helium pressure inside fuel rods.PurposeThis study aims to analyze the reliability of NDT testing method for the measurement of helium pressure inside fuel rods.MethodsThree standard rods with helium pressure values of 0.98 MPa, 1.76 MPa, 2.45 MPa, respectively, were selected for experimental test. The experimental fuel rods were first used to obtain the results comparison of heat transfer method and puncture manometry, then the control variates were employed to control the fuel rod temperature, the time interval of a single measurement, and the ambient temperature respectively, so as to determine influencing factors in the NDT method. Finally, reliability analysis of NDT method was performed according to experimental results.ResultsThe results of the NDT method are consistent with that of the puncture manometry method at a temperature range of 24~30 ºC with less than 0.05 MPa deviation. Minimum repeat measurement time interval for NDT measuring helium pressure of the same standard rod or fuel rod is 2 min.ConclusionsThe NDT method for measuring the helium pressure of fuel rods is reliable, and the measurement results are stable in different environmental conditions.