No abstract

Altered expression of Urea Cycle (UC) enzymes occurs in many tumors, resulting a metabolic hallmark termed as UC dysregulation. Polyamines are synthesized from ornithine, and polyamine synthetic genes are elevated in various tumors. However, the underlying deregulations of UC/ polyamine synthesis in cancer remain elusive. Here, we characterized a hypoxia-induced lncRNA LVBU (lncRNA regulation via BCL6/urea cycle) that is highly expressed in colorectal cancer (CRC) and correlates with poor cancer prognosis. Increased LVBU expression promoted CRC cells proliferation, foci formation and tumorigenesis. Further, LVBU regulates urea cycle and polyamine synthesis through BCL6, a negative regulator of p53. Mechanistically, overexpression of LVBU competitively bound miR-10a/miR-34c to protect BCL6 from miR-10a/34c-mediated degradation, which in turn allows BCL6 to block p53-mediated suppression of genes (arginase1 ARG1, ornithine transcarbamylase OTC, ornithine decarboxylase 1 ODC1) involved in UC/polyamine synthesis. Significantly, ODC1 inhibitor attenuated the growth of patient derived xenografts (PDX) that sustain high LVBU levels. Taken together, elevated LVBU can regulate BCL6-p53 signaling axis for systemic UC/polyamine synthesis reprogramming and confers a predilection toward CRC development. Our data demonstrates that further drug development and clinical evaluation of inhibiting UC/polyamine synthesis are warranted for CRC patients with high expression of LVBU.

The present work attempts to utilize iron tailings as the main raw materials for preparation of functional ceramics as a means of resource utilization. A new type of endothermic functional ceramics, which can be used in the field of solar energy, was prepared via semi-dry pressing followed by pressureless sintering. The results show that the functional ceramics made of 68 wt% iron tailings, 26 wt% iron ore, 3 wt% alumina, 1 wt% potash feldspar and 2 wt% kaolin, sintered at 1185°C exhibited the best overall performance. Visual observation reveals that there were no cracks on the surface of the samples even after 20 cycles of intense thermal shock. Other attributes could be summarized as follows: Infrared emissivity in mid-infrared region: 0.85; thermal conductivity at 500°C: 2.066 W/ (m·K); flexural strength: 119.03 MPa. XRD analysis indicates that the main crystalline phases in the samples are augite, magnetite and a small amount of hematite. An increase in the proportion of iron oxide contributed to lower melting temperature of the functional ceramics, deepen color, promote densification and increase infrared emissivity. In short, the introduction of iron tailings improves the thermal and physical properties to a certain extent.

Solid oxide fuel cell (SOFC) performance degradation analysis and optimization studies are important prerequisites for its commercialization. Reviewing and summarizing SOFC performance degradation studies can help researchers identify research gaps and increase investment in weak areas. In this study, to help researchers purposely improve system performance, degradation mechanism analysis, degradation performance prediction, and degradation performance optimization studies are sorted out. In the review, it is found that the degradation mechanism analysis studies can help to improve the system structure. Degradation mechanism analysis studies can be performed at the stack level and system level, respectively. Degradation performance prediction can help to take measures to mitigate degradation in advance. The main tools of prediction study can be divided into model-based, data-based, electrochemical impedance spectroscopy-based, and image-based approaches. Degradation performance optimization can improve the system performance based on degradation mechanism analysis and performance prediction results. The optimization study focuses on two aspects of constitutive improvement and health controller design. However, the existing research is not yet complete. In-depth studies on performance degradation are still needed to achieve further SOFC commercialization. This paper summarizes mainstream research methods, as well as deficiencies that can provide partial theoretical guidance for SOFC performance enhancement.

Purpose This paper aims to study a high-temperature (up to 200 °C) data acquisition and processing circuit for logging. Design/methodology/approach With the decrease in thermal resistance by system-in package technology and exquisite power consumption distribution design, the circuit worked well at high temperatures environment from both theoretical analysis and real experiments evaluation. Findings In thermal simulation, considering on board chips’ power consumption as additional heat source, the highest temperature point reached by all the chips in the circuit is only 211 °C at work temperature of 200 °C. In addition, the proposed circuit was validated by long time high-temperature experiments. The circuit showed good dynamic performance during a 4-h test in a 200-°C oven, and maintained a signal-to-noise ratio of 92.54 dB, a signal-to-noise and distortion ratio of 91.81 dB, a total harmonic distortion of −99.89 dB and a spurious free dynamic range of 100.28 dB. Originality/value The proposed circuit and methodology showed great potential for application in deep-well logging systems and other high-temperature situations.