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Surface nanodroplets are important units for lab-on-a-chip devices, compartmentalised catalytic reactions, high-resolution near-field imaging, and many others. Solvent exchange is a simple solution-based bottom-up approach for producing surface nanodroplets by displacing a good solvent of the droplet liquid by a poor one in a narrow channel in the laminar regime. The droplet size is controlled by the solution composition and the flow conditions during the solvent exchange. In this paper, we investigated the effects of local microfluidic structures on the formation of surface nanodroplets. The microstructures consist of a microgap with a well-defined geometry, embedded on the opposite microchannel wall, facing the substrate where nucleation takes place. For a given channel height, the dimensionless control parameters were the Peclet number of the flow, the ratio between the gap height and the channel height, and the aspect ratio between the gap length and the channel height. We found and explained three prominent features in the surface nanodroplet distribution at the surface opposite to the microgap: (i) enhanced volume of the droplets; (ii) asymmetry as compared to the location of the gap in the spatial droplet distribution with increasing Pe; (iii) reduced exponent of the effective scaling law of the droplet size with Pe. The droplet size also varied with the aspect and height ratios of the microgap at a given Pe value. Our simulations of the profile of oversaturation in the channel reveal that the droplet size distribution may be attributed to the local flow patterns induced by the gap. Finally, in a tapered microchannel, a gradient of surface nanodroplet size was obtained. Our work shows the potential for controlling nanodroplet size and spatial organization on a homogeneous surface in a bottom-up approach by simple microfluidic structures. [ABSTRACT FROM AUTHOR]

Mackerel icefish, Champsocephalus gunnari , plays a vital role in the Antarctic marine ecosystem, not only because it is an important prey for higher predators but also because it is the primary predator of Antarctic krill (Euphausia superba), a keystone species in the Southern Ocean. Therefore, elucidating the trophic linkage between C. gunnari and its exclusive prey can provide a model for the trophic relationship between a predator and its prey in cold environments. Stomach contents analysis showed that E. superba was the predominant prey of C. gunnari in terms of quantity (99.3%) and quality (99.9%) during winter at South Georgia. E. superba had a similar fatty acid profile to that of C. gunnari , with a high proportion of short-chain monounsaturated fatty acids (MUFA) and a lower proportion of long-chain MUFA. However, C. gunnari was more likely to retain polyunsaturated fatty acids, especially docosahexaenoic; E. superba tended to accumulate saturated fatty acids and MUFA. This reflects the fact that fatty acids, when transferred from low trophic level to higher levels, are accumulated in the predator selectively, according to their relative content in the diet and their physiological and ecological function in the predator. • Diet of Champsocephalus gunnari in South Georgia during winter was examined using stomach content and fatty acids analyses. • E. superba is the predominant prey of C. gunnari in South Georgia during winter. • E. superba and C. gunnari shared similar fatty acid profile. • C. gunnari retains polyunsaturated fatty acids, but E. superba accumulates saturated and monounsaturated fatty acids. • Study provide insight for predator-prey relationship in the Southern Ocean during data-limited season. [ABSTRACT FROM AUTHOR]

Patterning customized arrays of microscale Galinstan or EGaIn liquid metals enables the creation of a variety of microfabricated systems. Current techniques for creating microsized 3D structures of liquid metals are limited by the large dimension or low aspect ratio of such structures, and time-consuming processes. Here, a novel technique for creating 3D microstructures of Galinstan using dielectrophoresis is introduced. The presented technique enables the rapid creation of Galinstan microstructures with various dimensions and aspect ratios. Two series of proof-of-concept experiments are conducted to demonstrate the capabilities of this technique. First, the 3D Galinstan microstructures are utilized as 3D microelectrodes to enhance the trapping of tungsten trioxide (WO3) nanoparticles flowing through a microfluidic channel. Second, the patterned Galinstan microstructures are utilized as microfins to improve the dissipation of heat within a microfluidic channel that is located onto a hot spot. The presented technique can be readily used for creating customized arrays of 3D Galinstan microstructures for a wide range of applications. [ABSTRACT FROM AUTHOR]

In this article, we have employed this analysis on 5.69 inch panel. There are two white blocks on the left and right sides of the notch area. Those blocks look brighter than the other area. By means of modulating the timing of gate, we have succeeded to cover the luminance difference between two areas. The novel method can improve full display performance whether in design or verification phase. [ABSTRACT FROM AUTHOR]