To further study the proliferation and multi-differentiation potentials of adipose-derived stem cells (ADSCs), the cells were isolated with improved methods and their growth curves were achieved with cck-8. Surface protein expression was analyzed by flow cytometry to characterize the cell phenotype. The multi-lineage potential of ADSCs was testified by differentiating cells with adipogenic, chondrogenic, osteogenic, and myogenic inducers. The results showed that about 5 Â 10 5 stem cells could be obtained from 400 to 600 mg adipose tissue. The ADSCs can be continuously cultured in vitro for up to 1 month without passage and they have several logarithmic growth phases during the culture period. Also, the flow cytometry analysis showed that ADSCs expressed high levels of stem cell-related antigens (CD13, CD29, CD44, CD105, and CD166), while did not express hematopoiesis-related antigens CD34 and CD45, and human leukocyte antigen HLA-DR was also negative. Moreover, stem cell-related transcription factors, Nanog, Oct-4, Sox-2, and Rex-1 were positively expressed in ADSCs. The expression of alkaline phosphatase (ALP) was detected in the early osteogenic induction and the calcified nodules were observed by von Kossa staining. Intracellular lipid droplets could be observed by Oil Red staining. Differentiated cardiomyocytes were observed by connexin43 fluorescent staining. In order to obtain more stem cells, we can subculture ADSCs every 14 days instead of the normal 5 days. ADSCs still keep strong proliferation ability, maintain their phenotypes, and have stronger multi-differentiation potential after 25 passages.

Stable and efficient jumping droplet condensation is demonstrated on 3D superhydrophobic copper nanowire networks. Due to the interconnections among nanowires, the micro-defects in straight nanowire arrays are eliminated while the spacing between neighboring nanowires is reduced. By spatially controlling nucleation for highly mobile droplets, 100% higher heat flux is achieved compared with that on the state-of-the-art hydrophobic surface. The remarkable water repellency of 3D nanowire networks can be applied to a broad range of waterharvesting and phase-change heat transfer applications.

Rapid droplet removal by regulating surface topology and wettability has been exploited in nature and it is of great importance for a broad range of technological applications including water desalination and harvesting, power generation, environmental control, and thermal management. Recently there have been tremendous efforts in developing nanostructured surfaces for wettability control and enhancing phase-change heat transfer. However, the tendency of condensed droplets to form as pinned state rather than mobile mode on the nanostructured surfaces is likely to limit the applicability of such functionalized surfaces for condensation heat transfer enhancement. Here, we demonstrate enhanced condensation heat transfer on a nanowired hydrophobic copper surface where molecular permeation of water vapor into the separations between nanowires is greatly decreased, rendering spatial control on droplet nucleation and wetting dynamics. We show experimentally and theoretically that this novel strategy allows to achieve a 100% higher overall heat flux over a broadened surface subcooling range, up to 24 K, due to highly efficient droplet jumping compared to the state-of-the-art hydrophobic surfaces. These findings reveal that the droplet behaviors and condensation modes can be regulated by spatially controlling the nucleation events on the nanostructured surfaces, which paves the way for the design of nanostructured surfaces for enhanced phase-change heat transfer.

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