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The dynamic behavior of reed valves during suction and discharge is very important in predicting compressor performance and valve fatigue fracture. For an accurate dynamic analysis of reed valves, mass flow rate and effective force area should be accurately modeled. In this study, mass flow rate and effective force area models were developed based on CFD analysis results using the well-known commercial software ANSYS Fluent. CFD analyses were carried out for various values of port radius, valve radius, valve lift, and pressure difference. The mass flow rate and pressure force on valve were obtained from the analysis. Then, effective flow and force area models were proposed and the model coefficients were determined using the CFD results. The average prediction error of the effective flow area and the effective force area were 1.90% and 2.9%, respectively. It was shown that the effective flow area is dependent only on the port radii and valve lift; it is not dependent on the valve radii. The proposed effective force area model can accurately describe the decrease and increase in pressure force with valve lift.

Recently, we reported a novel therapeutic probiotic-derived protein, p8, which has anti-colorectal cancer (anti-CRC) properties. In vitro experiments using a CRC cell line (DLD-1), anti-proliferation activity (about 20%) did not improve after increasing the dose of recombinant-p8 (r-p8) to &gt, 10 &mu, M. Here, we show that this was due to the low penetrative efficiency of r-p8 exogenous treatment. Furthermore, we found that r-p8 entered the cytosol through endocytosis, which might be a reason for the low penetration efficiency. Therefore, to improve the therapeutic efficacy of p8, we tried to improve delivery to CRC cells. This resulted in endogenous expression of p8 and increased the anti-proliferative effects by up to 2-fold compared with the exogenous treatment (40 &mu, M). Anti-migration activity also increased markedly. Furthermore, we found that the anti-proliferation activity of p8 was mediated by inhibition of the p53-p21-Cyclin B1/Cdk1 signal pathway, resulting in growth arrest at the G2 phase of the cell cycle. Taken together, these results suggest that p8 is toxic to cancer cells, shows stable expression within cells, and shows strong cancer suppressive activity by inducing cell cycle arrest. Therefore, p8 is a strong candidate for gene therapy if it can be loaded onto cancer-specific viruses.

Global challenges including overpopulation, climate change, and income inequality have increased, and a demand for sustainability has emerged. Decision-making for sustainable development is multifaceted and interlinked, owing to the diverse interests of different stakeholders and political conflicts. Analysing a situation from all social, political, environmental, and economic perspectives is necessary to achieve balanced growth and facilitate sustainable development. South Korea was among the poorest countries following the Korean War, however, it has developed rapidly since 1955. This growth was not limited to economic development alone, and the chronology of South Korean development may serve as a reference for development in other countries. Here, we explore the compressed growth of South Korea using a narrative approach and time-series, comparative, and spatial analyses. Developmental indicators, along with the modern history of South Korea, are introduced to explain the reasons for compressed growth. The development of the mid-latitude region comprising 46 countries in this study, where nearly half of Earth’s population resides, was compared with that of South Korea, results show that the developmental chronology of South Korea can serve as a reference for national development in this region.