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Integrin-mediated focal adhesion (FA) and subsequent cytoskeletal reorganization influence cell morphology, migration, and ultimately cell fate. Previous studies have used various patterned surfaces with defined macroscopic cell shapes or nanoscopic FA distributions to explore how different substrates affect the fate of human bone marrow mesenchymal stem cells (BMSCs). However, there is currently no straightforward relationship between BMSC cell fates induced by patterned surfaces and FA distribution substrates. In this study, we conducted single-cell image analysis of integrin α v -mediated FA and cell morphological features of BMSCs during biochemically induced differentiation. This enabled the identification of distinct FA features that can discriminate between osteogenic and adipogenic differentiation, demonstrating that integrin α v -mediated focal adhesion (FA) can be used as a non-invasive biomarker for real time observation. Based on these results, we developed an organized microscale fibronectin (FN) patterned surface where the fate of BMSC could be precisely manipulated by these FA features. Notably, even in the absence of any biochemical inducers, such as those contained in the differentiation medium, BMSCs cultured on these FN patterned surfaces exhibited upregulation of differentiation markers comparable to BMSCs cultured using conventional differentiation methods. Therefore, the present study reveals the application of these FA features as universal markers not only for predicting differentiation status, but also for regulating cell fate by precisely controlling the FA features with a new cell culture platform. Although the effects of material physiochemical properties on cell morphology and subsequent cell fate decisions have been extensively studied, a simple yet intuitive correlation between cellular features and differentiation remains unavailable. We present a single cell image-based strategy for predicting and directing stem cell fate. By using a specific integrin isoform, integrin α v , we identified distinct geometric features that can be used as a marker for discriminating between osteogenic and adipogenic differentiation in real-time. From these data, new cell culture platforms capable of regulating cell fate by precisely controlling FA features and cell area can be developed. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The air-side heat transfer characteristics of flat plate finned-tube heat exchangers were measured and analyzed by varying the fin pitch, number of tube rows, and tube alignment under frosting conditions. Two empirical correlations for predicting the j-factor were developed separately for the inline and the staggered tube alignment, respectively, as a function of the Reynolds number, Fourier number, number of tube rows, and dimensionless hydraulic diameter normalized by fin pitch. The average deviation of the predictions of the present correlations from the measured data was 1.31% for the inline tube alignment and 0.65% for the staggered tube alignment. [Copyright &y& Elsevier]

Abstract: The objective of this study is to provide experimental data that can be used in the optimal design of flat plate finned-tube heat exchangers with large fin pitch. In this study, 22 heat exchangers were tested with a variation of fin pitch, number of tube row, and tube alignment. The air-side heat transfer coefficient decreased with a reduction of the fin pitch and an increase of the number of tube row. The reduction in the heat transfer coefficient of the four-row heat exchanger coil was approximately 10% as the fin pitch decreased from 15.0 to 7.5mm over the Reynolds number range of 500–900 that was calculated based on the tube diameter. For all fin pitches, the heat transfer coefficient decreased as the number of tube row increased from 1 to 4. The staggered tube alignment improved heat transfer performance more than 10% compared to the inline tube alignment. A heat transfer correlation was developed from the measured data for flat plate finned-tubes with large fin pitch. The correlation yielded good predictions of the measured data with mean deviations of 3.8 and 6.2% for the inline and staggered tube alignment, respectively. [Copyright &y& Elsevier]

In this study, a method to evaluate the environmental effects of household refrigerators is newly developed in terms of life cycle climate performance (LCCP). The energy consumption model of the refrigerator is developed with three types of typical single evaporator refrigerators. The operation ratio of the evaporators, which is critical for calculating the energy consumption of dual evaporator refrigerators, is determined using experimental results of serial, bypass, and parallel-circuit cycle refrigerators. The LCCP results show that the system performance and equipment manufacturing emissions are dominant factors in lifetime CO 2 emissions. Therefore, energy- and material-related factors, such as refrigerator cycle options, refrigerator material, insulation, and power sources, are primarily investigated. For cycle options, CO 2 emissions can be reduced by 14.7% using a two-stage cycle. For condenser materials, CO 2 emissions can be reduced by 2% to 2.5% using aluminum instead of steel. For insulation, the total emissions can be reduced by up to 7.7% by applying vacuum insulation panels on each side of the refrigerator. When 20% renewable energy is supplied, the total emissions are expected to be reduced by 13% in the baseline, 19.9% in the parallel-circuit cycle, and 26% in the two-stage cycle. [ABSTRACT FROM AUTHOR]