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Diphenylacetylene derivatives containing different polymeric components, poly(l-lysine) (pLys) or tetra(ethylene glycol) (TEG) were designed as novel Raman imaging probes with high Raman sensitivity and low cytotoxicity in living plant cells. The pLys-conjugated probe is internalized via an endocytosis-dependent pathway, whereas TEG-conjugated probe most likely induces direct penetration into the plant cells., Diphenyl acetylene derivatives containing various polymeric components have been designed as new Raman imaging probes. These are taken up by plant cells via different pathways, and the internalization of exogenous molecules can be visualized.

Time-course analysis of single cells is important to characterize heterogeneous activities of individual cells such as the metabolic response to their environment. Single-cell isolation is an essential step prior to time-course analysis of individual cells by collecting, culturing, and identifying multiple single-cell targets. Although single-cell isolation has been performed by various methods previously, a glass microfluidic device with semiclosed microchannels dramatically improved this process with its simple operation and easy transfer for time-course analysis of identified single cells. This study demonstrates isolating single cells of the highly motile microalgae, Euglena gracilis, by semiclosed microchannels with liquid flow only. The isolated single cells were identified in isolating channels and continuously cultured to track, by Raman microscopy, for the formation of subcellular granules composed of polysaccharide paramylon, a unique metabolite of E. gracilis, generated through photosynthesis. Through low-temperature glass bonding, a thin glass interface was incorporated to the microfluidic device. Thus, the device could perform the direct measurements of cultured single cells at high magnification by Raman microscopy with low background noise. In this study, the first demonstration of sequential monitoring of paramylon biogenesis in a single identified E. gracilis cell is shown.

Recent development of stimulated Raman scattering (SRS) microscopy allows for label-free biological imaging with chemical specificity based on molecular-vibrational signatures. In particular, hyperspectral SRS imaging can acquire a molecular-vibrational spectrum at each pixel, allowing us not only to investigate the spectral difference of various biological molecules but also to discriminate different constituents based on their spectral difference. However, the number of constituents discriminated in previous label-free SRS imaging was limited to four because of the subtleness of spectral difference. Here, we report hyperspectral SRS imaging of plant tissues including leaves of Camellia japonica, roots of Arabidopsis thaliana, and thalli of a liverwort Marchantia polymorpha L. We show that SRS can discriminate as many as six components in Marchantia polymorpha L. without labeling. Our results demonstrate the effectiveness of hyperspectral SRS imaging as a tool for label-free multicolour imaging analysis of various biomolecules in plant tissues.

We have developed a two-way multi-view 2-D/3-D display combining a liquid crystal lens and horizontally and vertically x times-density pixels (HVxDP) arrangement. The two-way multi-view display features the same display resolution in 2-D and 3-D modes and a quite small color moire for landscape and portrait, respectively, when using the HVxDP arrangement. In this paper, we realized suitable 3-D properties for achieving a good balance between 3-D moire and 3-D crosstalk for landscape and portrait by a two-way liquid crystal lens with two kinds of focal lengths for the edge part and the center part of the lens.

The management of oily wastewater produced in the petrochemical industries poses an immense challenge from both practical and environmental points of view. Filtration using ceramic membranes has been considered a promising technology to remove stable emulsions from oily wastewater; however, the separation performances are severely limited by membrane fouling. In this study, we evaluated the filtration performance of porous ceramic membranes for the treatment of oil/water emulsions. Porous ceramic membrane, having different pore sizes (0.1–1.4 μm) and made from various materials (Al2O3, TiO2–ZrO2, TiO2, and SiC), were tested in a crossflow microfiltration system using oil/water emulsions. The emulsions were stabilized by anionic and cationic surfactants. The fouling caused by filtration is discussed in terms if membrane and emulsion properties. Pore size and surface charge were the two most important prominent fouling factors during the oil/water emulsion filtrations. For membranes with small pores, serious fouling was observed, irrespective of the type of surfactant; however, these membranes exhibited excellent oil rejection. The fouling was caused by the accumulation of oil droplets on the membrane surface, which subsequently led to the formation of a cake layer and/or a continuous oil layer. The effect of surface charge became significant regarding membranes of larger pore sizes, especially when membrane pore sizes were comparable to that of the droplet sizes. When the membrane and oil droplets had the same charge, electrostatic repulsion occurred, preventing the penetration of oil droplets into the pores. Although some of the small oil droplets could enter the pores, they would be trapped at the narrowing and/or flexing inside the pores because droplet deformation was inhibited by the electrostatic repulsion. Therefore, fouling occurred on the membrane surface and inside. As a result, a severe decline in water permeation was observed, together with a moderate oil rejection. By contrast, when the membrane and oil droplets were oppositely charged, oil droplets were deformed and entered the pores, resulting in permeation through the membrane. Therefore, water permeation was high, but oil rejection was sacrificed. These results indicate that both pore size and surface charge of membranes should be optimized to achieve better filtration performance.