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Excessive carbon emissions are one of the global challenges. Promoting the optimization of high-efficiency heat transfer systems and improving the analysis and evaluation methods of heat exchangers is one of the effective ways to save energy and reduce carbon emissions. The traditional thermal resistance analysis method treats the fluid domain as a uniform whole, which makes it difficult to regulate the heat transfer characteristics in local regions, especially in the near-wall region. To address this problem, this paper obtained the thermal resistance mathematical equation for different regions in the flow field by magnitude analysis. The thermal resistance delamination method for dividing the thermal resistance field is proposed from the channel flow, and the conduction, mixing and advection zones in the flow field are identified. The delamination factor (α) is defined to determine the boundaries of thermal resistance zones. The α values which meet the delamination factor independence under forced convection and natural convection conditions are investigated. By studying the mechanism of the thermal resistance in conduction zone of the enhanced heat transfer structure, the critical value of fin height to achieve maximum enhancement efficiency is determined. The thermal resistance delamination facilitates a comprehensive analysis of heat transfer processes and structure optimization in the near-wall region. • Thermal resistance delamination method based on flow characteristics is proposed. • The expression of each thermal resistance zone was determined by sensitivity analyses and delamination factor. • Analysis of heat transfer in enhanced double-sided channel flow based on thermal resistance delamination method. • Critical fin height for maximum enhancement efficiency determined by local thermal resistance. [ABSTRACT FROM AUTHOR]

• PCM capsules are used for thermal insulation of deice in downhole. • Various stacking structures of PCM capsules are numerically studied. • Shock properties including wave, area, frequency are analyzed. • The staggered structure shows the best thermal shock shielding performance. Pulsed power sources (PPS) are commonly employed for the exploitation and extraction of shale oil in deep downhole environments. Nevertheless, the extreme conditions, such as high temperature and high pressure, pose significant challenges to the safe operation of PPS systems due to electronic failures. In this study, capsules filled with phase change material (PCM) under three layouts are proposed, aiming to provide thermal protection and shock shielding for PPS devices. Numerical methods are applied to PCM capsules, and the properties of PCM capsules are obtained through experimental measurements. Results show that the staggered stacking structure shows the best thermal protection performance, with a phase change duration 14.1 % longer than that of the double layer stacking structure. Additionally, considering the effect of the shock wave generated by the PPS, the shock properties of the ordered stacking thermal protection structure at different phase transition stages and different structures are discussed. The double layer stacking structure has a smaller shock area, and the extreme range of the peak shock wave is 34.89 kPa, which is only 0.5 times that of the single layer array, but its internal shock frequency is larger than the latter. As a result, the staggered stacking structure is recommended, considering both thermal protection and shock shielding features. [ABSTRACT FROM AUTHOR]

• The concept of multi-dimensional conduction-advection thermal resistance in parallel in fluid domain is proposed. • The advection thermal resistance in the fluid domain is closely related to the magnitude and direction of temperature gradient and velocity. • "Negative thermal resistance" in the advection thermal resistance is found to be equivalent to a "heat source" or a "heat sink" in the fluid domain. • The capability of analysis methodology of conduction-advection thermal resistance in parallel is illustrated and proved. Thermo-electric analogy method and thermal resistance are widely used for heat transfer problems to simplify the analysis process of complex heat transfer network. Traditional thermal resistance is usually applicable to one-dimensional steady state heat conduction problem. However, heat convection problem is always involved in engineering applications such as energy power, petrochemical, aerospace and so on. In order to solve this problem, the concept of multi-dimensional conduction-advection thermal resistance in parallel in fluid domain is proposed, and the conduction-advection thermal resistance network with heat capacity is constructed. The advection thermal resistance in the fluid domain is closely related to the magnitude and direction of temperature gradient and velocity. The higher the velocity, the smaller the advection thermal resistance. Simultaneously, there exists a "negative thermal resistance" in the advection thermal resistance, which is equivalent to a "heat source" or a "heat sink" in the fluid domain. A forced convection problem and a natural convection problem are taken as examples to illustrate the practicality of this thermal resistance analysis methodology. The results show that the conduction-advection parallel thermal resistance network is important to analyze the flow and heat transfer processes and guide the regulation and optimization of the heat transfer processes. [ABSTRACT FROM AUTHOR]

Heat collection through flat plate collector is a common technology in solar thermal utilization. In order to improve the heat collection efficiency of flat plate collector and determine the best inclination angle and glass plate thickness, this paper establishes a collector indoor experimental system, and completes the research of solar radiation intensity, collector inclination angle, mass flow rate and glass thickness on the heat collection performance of corrugated flat plate collector. The result shows that when radiation intensity is 510W/m2, the temperature difference between the inlet and outlet in the radiation decreasing stage is 0.25 °C higher than the radiation increasing stage, and the heat collection in the radiation decreasing stage is 157.5W higher than the radiation increasing stage. The heat collection efficiency under different inclination angles decreases with the increase of radiation intensity, the best inclination angle of the collector is 45° and the maximum heat collection efficiency is 0.89. When the radiation intensity is more than 1000W/m2, heat collection of flat plate collector with glass thickness of 8 mm is 6% higher than that with the thickness of 6 mm, insulating effect of the glass is more obvious. The optimum thickness of the glass plate is 4 mm, the maximum temperature difference is 1.5 °C and the maximum heat collection efficiency is 0.89. The heat collection efficiency at different mass flow rates increases first and then decreases with the increase of radiation intensity. The maximum value of the heat collection efficiency at low mass flow rate is delayed. When the mass flow rate is 0.15 kg/s, 0.13 kg/s and 0.1 kg/s, the maximum heat collection efficiency is 0.89, 0.86 and 0.73, respectively; and the corresponding radiation intensity are 670W/m2, 850W/m2 and 1000W/m2, respectively. • Heat collection performance analysis of corrugated flat plate collector was studied. • Temperature difference during the descending stage of radiation intensity is greater. • The greater radiation intensity, the more obvious insulating effect of the glass. • There is apparent delay in the maximum efficiency value of the low mass flow rate.. [ABSTRACT FROM AUTHOR]

• Natural plant schinifoline has a certain inhibitory effect on the treatment of Candida albicans in C. elegans. • The results showed that the pathogenicity of C. albicans to C. elegans was caused by abnormal protein function. • Schinifoline regulates lysosomal pathway related genes that accelerate the metabolism and degradation of abnormal proteins. Candida albicans is an opportunistic fungal human pathogen that has been causing an increasing number of deaths each year. Due to the widespread use of broad-spectrum antibiotics and immunosuppressants, C. albicans resistance to these therapies has increased. Thus, natural plant inhibitors are being investigated for treating C. albicans infections. Schinifoline is a 4-quinolinone alkaloid with antibacterial, insecticidal, antitumor, and other biological activities. Here, we explored the effects of schinifoline on C. albicans in C. elegans and extracted RNA from uninfected C. elegans , C. elegans infected with C. albicans , and C. elegans infected with C. albicans and treated with 100 mg/l schinifoline. Our results showed that there were significant differences among the three groups. The GO and KEGG pathway analysis suggested that the pathogenicity of C. albicans to C. elegans was caused by abnormal protein function. Schinifoline regulates lysosomal pathway related genes that accelerate the metabolism and degradation of abnormal proteins, thereby inhibiting the negative effects of C. albicans in vivo. These findings advance our understanding of the molecular mechanisms underlying schinifoline inhibition of C. albicans. [ABSTRACT FROM AUTHOR]

The dependency of prostate cancer (PCa) growth on androgen receptor (AR) signaling has been harnessed to develop first-line therapies for high-risk localized and metastatic PCa treatment. However, the occurrence of aberrant expression, mutated or splice variants of AR confers resistance to androgen ablation therapy (ADT), radiotherapy or chemotherapy in AR-positive PCa. Therapeutic strategies that effectively inhibit the expression and/or transcriptional activity of full-length AR, mutated AR and AR splice variants have remained elusive. In this study, we report that mithramycin (MTM), an antineoplastic antibiotic, suppresses cell proliferation and exhibits dual inhibitory effects on expression and transcriptional activity of AR and AR splice variants. MTM blocks AR recruitment to its genomic targets by occupying AR enhancers and causes downregulation of AR target genes, which includes key DNA repair factors in DNA damage repair (DDR). We show that MTM significantly impairs DDR and enhances the effectiveness of ionizing radiation or the radiomimetic agent Bleomycin in PCa. Thus, the combination of MTM treatment with RT or radiomimetic agents, such as bleomycin, may present a novel effective therapeutic strategy for patients with high-risk, clinically localized PCa. [ABSTRACT FROM AUTHOR]

Cinnamon is the dried bark of Cinnamomum cassia Presl, and its main component is cinnamaldehyde (CA). Decades of synthetic pesticide use to control parasitic nematodes that can harm plants has seriously polluted the environment and poses a risk to soil ecology, highlighting the need to develop natural biological pesticides. Some species classified under Nematoda are highly similar, therefore we used the model organism C. elegans to explore the effect of cinnamaldehyde, a plant-derived natural product, on C. elegans viability. We found that the lethal dose of cinnamaldehyde for C. elegans treatment for 4 h at a concentration of 800 mg/L. Sequencing-based transcriptome data revealed differences between the cinnamaldehyde treatment and control groups. RNA-seq analysis showed that C. elegans exposed to cinnamaldehyde had significantly altered expression of metabolic genes, particularly for genes involved in glutathione metabolism (gst-1, gst-2, gst-4, gst-5, gst-6, gst-7, gst-8, gst-25, gst-30, gst-38, gst-44, and gcs-1). Therefore, glutathione metabolism is altered in C. elegans upon exposure to cinnamaldehyde. Based on the above results, treatment with 800 mg/L of cinnamaldehyde for 4 h was selected for all experiments in nematodes. Given these findings, cinnamaldehyde may be a promising natural alternative to synthetic pesticides for controlling plant parasitic nematodes with low cost, high efficiency, and diminished environmental pollution. Unlabelled Image • 800 mg/L cinnamaldehyde has lethal effect on C. elegans exposure for 4 h • Cinnamaldehyde affects the metabolic system of C. elegans , especially glutathione metabolism. • The death of C. elegans is due to a change in gst-1, gst-2, gst-4, gst-5, gst-6, gst-7, gst-8, gst-25, gst-30, gst-38, gst-44, and gcs-1. [ABSTRACT FROM AUTHOR]