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Wireless multimedia sensor networks have recently emerged as one of the most important technologies to actively perceive physical world and empower a wide spectrum of potential applications in various areas. Due to the advantages of rapid deployment, flexible networking, and multimedia information perceiving, wireless multimedia sensor networks are suitable for transmitting mass multimedia data such as audio, video, and images. Two-dimensional images are among the nuclear ways to convey certain information, and there exists a large number of image data to be processed and transmitted; however, the complexity of environment and the instability of sensing component both can give rise to the insignificant information of the resulted images. Hence, image processing attracts a lot of research concerns in last several decades. Our concern in this article is filtering technology on image signal. Filtering is shown to be a key technique to ensure the validity and reliability of the wireless multimedia sensor networks images, which aims to preserve salient edges and remove low-amplitude structures. The well-known L0 gradient minimization employs L0 norm as gradient sparsity prior, and it is capable of preserving sharp edges. Similar to the total variation model, L0 gradient minimization may easily suffer from the staircase effect and even lose part of the structure. Therefore, in this article, we propose an edge-preserving filter with adaptive L0 gradient optimization. Different from original L0 gradient minimization, we introduce an adaptive L0 regularization. The newly proposed adaptive function is feature-driven and makes the utmost of the image gradient, enabling the filter to remove low-amplitude structures and preserve key edges. Furthermore, the proposed filter can effectively avoid staircase effect and is robust to noise. We develop an efficient optimization algorithm to solve the proposed model based on alternating minimization. Through extensive experiments, our method shows many attractive properties like preserving meaningful edges, avoiding staircase effect, robustness to noise, and so on. Applications including noise reduction, clip-art compression artifact removal, detail enhancement and edge extraction, image abstraction and pencil sketching, and high dynamic range tone mapping further demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: In the past few decades, microalgae biofuel has become one of the most interesting sources of renewable energy. However, the higher cost of microalgae biofuel compared to that of petroleum prevented microalgae biofuel production. Therefore, the research on increasing lipid productivity from microalgae becomes more important. The lipid production source, triacylglycerol biosynthesis in microalgae requires short chain fatty acids as substrates, which are synthesized in chloroplasts. However, the transport mechanism of fatty acids from microalgae chloroplasts to cytosol remains unknown. Results: cDNAs from two homologs of the Arabidopsis fatty acid exporter 1 (FAX1) were cloned from Chlamydomonas reinhardtii and were named crfax1 and crfax2. Both CrFAXs were involved in fatty acid transport, and their substrates were mainly C16 and C18 fatty acids. Overexpression of both CrFAXs increased the accumulation of the total lipid content in algae cells, and the fatty acid compositions were changed under normal TAP or nitrogen deprivation conditions. Overexpression of both CrFAXs also increased the chlorophyll content. The MGDG content was decreased but the TAG, DAG, DGDG and other lipid contents were increased in CrFAXs overexpression strains. Conclusion: These results reveal that CrFAX1 and CrFAX2 were involved in mediating fatty acid export for lipids biosynthesis in C. reinhardtii. In addition, overexpression of both CrFAXs obviously increased the intracellular lipid content, especially the triacylglycerol content in microalgae, which provides a potential technology for the production of more biofuels using microalgae. [ABSTRACT FROM AUTHOR]

The polyamidoamine (PAMAM) dendrimer is a highly efficient absorption promoter. In the present study, we studied the absorption-enhancing effects and the mechanism of PAMAM dendrimers with generation 0 to generation 3 (G0–G3) and concentrations (0.1–1.0%) on the pulmonary absorption of macromolecules. The absorption-enhancing mechanisms were elucidated by microarray, western blotting analysis, and PCR. Fluorescein isothiocyanate-labeled dextrans (FDs) with various molecular weights were used as model drugs of poorly absorbable drugs. The absorption-enhancing effects of PAMAM dendrimers on the pulmonary absorption of FDs were in a generation- and concentration-dependent manner. The G3 PAMAM dendrimer with high effectiveness was considered to the best absorption enhancer for improving the pulmonary absorption of FDs. G3 PAMAM dendrimers at three different concentrations were non-toxic to Calu-3 cells. Based on the consideration between efficacy and cost, the 0.1% G3 PAMAM dendrimer was selected for subsequent studies. The results showed that treatment with a 0.1% G3 PAMAM dendrimer could increase the secretion of organic cation transporters (OCTs), OCT1, OCT2, and OCT3, which might be related to the absorption-enhancing mechanisms of the pulmonary absorption of FDs. These findings suggested that PAMAM dendrimers might be potentially safe absorption enhancers for improving absorption of FDs by increasing the secretion of OCT1, OCT2, and OCT3. [ABSTRACT FROM AUTHOR]

Background: Tumor PD-L1 levels have predictive value in PD-1/PD-L1 checkpoint blockade therapies, yet biopsies can only provide baseline information. Whether PD-L1 expression on circulating tumor cells (CTCs) could serve as an alternative biomarker is of great interest. Design: We established an immunofluorescence assay for semi-quantitative assessment of the PD-L1 expression levels on CTCs with four categories (PD-L1negative, PD-L1low, PD-L1medium and PD-L1high). 35 patients with different advanced gastrointestinal tumors were enrolled in a phase 1 trial of a PD-1 inhibitor, IBI308. The CTC numeration and the PD-L1 expression levels were analyzed. Results: Prior the treatment of IBI308, 97% (34/35) patients had CTCs, ranging from1 to 70 (median 7). 74% (26/35) had PD-L1positive CTCs, and 60% (21/35) had at least one PD-L1high CTCs. The disease control (DC) rate in PD-L1high patients (48%) is much higher than the others (14%). The group with at least 20% abundance of PD-L1high CTCs had even higher DC rate of 64% (9/14), with only 14% DC rate for the rest (3/21). We also observed that the count changes of total CTC, PD-L1postive CTC and PD-L1high CTC correlate quite well with disease outcome (P<0.001, P = 0.002 and 0.007, respectively). In addition, the abundance of PD-L1high CTCs at baseline had predicative significance for progression free survival (PFS). Conclusions: We revealed that the abundance of PD-L1high CTCs at baseline might serve as a predictor to screen patients for PD-1/PD-L1 blockade therapies and measuring the dynamic changes of CTC could indicate the therapeutic response at early time. [ABSTRACT FROM AUTHOR]