Exposure of cells to ultraviolet B (UVB) radiation can induce production of free radicals and reactive oxygen species (ROS), which damage cellular components. In addition, these agents can stimulate the expression of matrix metalloproteinase (MMP) and decrease collagen synthesis in human skin cells. In this study, we examined the anti-photoaging effects of extracts of Tetraselmis suecica (W-TS). W-TS showed the strongest scavenging activity against 2,2-difenyl-1-picrylhydrazyl (DPPH) and peroxyl radicals, followed by superoxide anions from the xanthine/xanthine oxidase system. We observed that the levels of both intracellular ROS and lipid peroxidation significantly increased in UVB-irradiated human skin fibroblast cells. Furthermore, the activities of enzymatic antioxidants (e.g., superoxide dismutase) and the levels of non-enzymatic antioxidants (e.g., glutathione) significantly decreased in cells. However, W-TS pretreatment, at the maximum tested concentration, significantly decreased intracellular ROS and malondialdehyde (MDA) levels, and increased superoxide dismutase and glutathione levels in the cells. At this same concentration, W-TS did not show cytotoxicity. Type 1 procollagen and MMP-1 released were quantified using RT-PCR techniques. The results showed that W-TS protected type 1 procollagen against UVBinduced depletion in fibroblast cells in a dose-dependent manner via inhibition of UVB-induced MMP-1. Taken together, the results of the study suggest that W-TS effectively inhibits UVB-induced photoaging in skin fibroblasts by its strong anti-oxidant ability.

Finding optimal panel tilt angle of photovoltaic system is an important matter as it would convert the amount of sunlight received into energy efficiently. Numbers of studies used various research methods to find tilt angle that maximizes the amount of radiation received by the solar panel. However, recent studies have found that conversion efficiency is not solely dependent on the amount of radiation received. In this study, we propose a solar panel tilt angle optimization model using machine learning algorithms. Rather than trying to maximize the received radiation, the objective is to find tilt angle that maximizes the converted energy of photovoltaic (PV) systems. Considering various factors such as weather, dust level, and aerosol level, five forecasting models were constructed using linear regression (LR), least absolute shrinkage and selection operator (LASSO), random forest (RF), support vector machine (SVM), and gradient boosting (GB). Using the best forecasting model, our model showed increase in PV output compared with optimal angle models.

Raphanus sativus (Cruciferaceae), commonly known as radish is widely available throughout the world. From antiquity it has been used in folk medicine as a natural drug against many toxicants. The present study was designed to evaluate the hepatoprotective activity of radish (Raphanus sativus) enzyme extract (REE) in vitro and in vivo test. The IC50 values of REE in human liver derived HepG2 cells was over 5,000 μg/ml in tested maximum concentration. The effect of REE to protect tacrine-induced cytotoxicity in HepG2 cells was evaluated by MTT assay. REE showed their hepatoprotective activities on tacrineinduced cytotoxicity and the EC50 value was 1,250 μg/ml. Silymarin, an antihepatotoxic agent used as a positive control exhibited 59.7% hepatoprotective activitiy at 100 μg/ml. Moreover, we tested the effect of REE on carbon tetrachloride (CCl4)-induced liver toxicity in rats. REE at dose of 50 and 100 mg/kg and silymarin at dose of 50 mg/kg were orally administered to CCl4-treated rats. The results showed that REE and silymarin significantly reduced the elevated levels of serum enzyme markers induced by CCl4. The biochemical data were supported by evaluation with liver histopathology. These findings suggest that REE, can significantly diminish hepatic damage by toxic agent such as tacrine or CCl4.

Polydimethyl-siloxane (PDMS) is often applied to fabricate cell chips. In this study, we fabricated an adipocyte microcell pattern chips using PDMS to analyze the inhibition activity of lipid droplets in mouse embryo fibroblast cells (3T3-L1) with anti-obesity agents. To form the PDMS based micropattern, we applied the micro-contact printing technique using PDMS micro-stamps that had been fabricated by conventional soft lithography. This PDMS micro-pattern enabled the selective growth of 3T3-L1 cells onto the specific region by preventing cell adhesion on the PDMS region. It then allowed growth of the 3T3-L1 cells in the chip for 10 days and confirmed that lipid droplets were formed in the 3T3-L1 cells. After treatment of orlistat and quercetin were treated in an adipocyte micro-cell pattern chip with 3T3-L1 cells for six days, we found that orlistat and quercetin exhibited fat inhibition capacities of 19.3% and 24.4% from 0.2 μM of lipid droplets in 3T3-L1 cells. In addition, we conducted a direct quantitative analysis of 3T3-L1 cell differentiation using Oil Red O staining. In conclusion, PDMS-based adipocyte micro-cell pattern chips may contribute to the development of novel bioactive compounds.

A simple, rapid, and convenient colorimetric chemosensor of a specific target toward the end user is still required for on-site detection and real-time monitoring applications. In this study, we developed a rapid in situ colorimetric assay for cobalt detection using the naked eye. Interestingly, a yellow to light orange visual color transition was observed within 3 s when a Chrysoidine G (CG) chemosensor was exposed to cobalt. Surprisingly, the CG chemosensor had great selectivity toward cobalt without any interference of other metal ions. Under optimized conditions, a lower detection limit of 0.1 ppm via a spectrophotometer and a visual detection limit of 2 ppm with a linear range from 0.4 to 1 ppm (R2 = 0.97) were determined. Moreover, the CG chemosensor is reversible and maintains its functionality after treatment with chelating agents. In conclusion, we show the superior capabilities of the CG chemosensor, which has the potential to provide extremely facile handling, high sensitivity, and a fast response time for applications of on-site detection to real-time cobalt monitoring for the general public.

Abstract:The heat transfer in the turbocharger occurs due to the temperature difference between the exhaust gas and intake air, coolant, and oil. This heat transfer causes the efficiency of the compressor and turbine to be distorted, which is known to be exacerbated during low rotational speeds. Thus, this study proposes a method to mitigate the distortion of the test result data caused by heat transfer in the turbocharger. With this method, the representative compressor temperature is defined and the heat transfer rate of the compressor is calculated by considering the effect of the oil and turbine inlet temperatures at low rotation speeds, when the cold and the hot gas test are simultaneously performed. The correction of compressor efficiency, depending on the turbine inlet temperature, was performed through both hot and cold gas tests and the results showed a maximum of 16% error prior to correction and a maximum of 3% error after the correction. In addition, it shows that it is possible to correct the efficiency distortion of the turbocharger by heat transfer by correcting to the combined turbine efficiency based on the corrected compressor efficiency.

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BACKGROUND: Obesity is a growing global problem and an efficient screening method to discover anti-obesity agents on a simple platform is needed. Polydimethylsiloxane (PDMS)-based micro-cell chips are widely applied to cell studies because of their non-toxicity and biocompatibility. RESULTS: 3T3-L1 cells were cultured on a micro-cell pattern chip. After 6 days, we successfully observed adipocyte differentiation in 3T3-L1 cells within the micro-cell pattern chip. Next, 3T3-L1 cells on the micro-cell patterned chip were then treated under various concentrations of glycitein and 7,3 ′ ,4 ′ -trihydrxyisoflavone (0.2, 0.5 and 1.0 mol L −1 ) for 10 days. Glycitein and 7,3 ′ ,4 ′ -trihydrxyisoflavone exhibited a fat inhibitory capacity of higher than 36% and 44% at 1.0 mol L −1 in 3T3-L1 adipocytes, suggesting anti-obesity activity. It was demonstrated that this platform can be used for real-time monitoring of cell growth and differentiation in live cell-based lipid droplets inhibition activity. CONCLUSION: A micro-cell pattern chip was made using PDMS microstamps through micro-molding for an efficient, rapid, and reliable cell selective patterning of 3T3-L1 cells differentiation. The present work provides a proof-of-principle demonstration of the direct qualitative and quantitative analysis of adipocyte differentiation through a simple microscopic observation of OilRed O staining for lipid droplets in cell array patterning. PDMS based micro-cell pattern chips can be used for the screening of anti-obesity agents such as glycitein and 7,3 ′ ,4 ′ -trihydrxyisoflavone. Furthermore, it is expected that micro-cell pattern chip technology could be applied to the development of novel bioactive compounds.