Output Reachable Set-Based Leader-Following Consensus of Positive Agents Over Switching Networks.

This work addresses the output reachable set-based leader-following consensus problem, focusing on a group of positive agents over directed dwell-time switching networks. Two types of non-negative disturbances, namely, 1) L1 -norm bounded disturbances and 2) L∞,1 -norm bounded disturbances are studied. Meanwhile, a class of directed dwell-time switching networks for modeling the communication protocol of positive agents is investigated. To deal with the presence of disturbances, an output-feedback control protocol is developed to achieve a robust consensus with positivity preserved based on the output reachable set. By exploiting the positive characteristics, switched linear copositive Lyapunov functions are adopted to establish output reachable set-based consensus conditions. These conditions can facilitate the control protocol design by solving a bilinear programming problem, and also generate hyperpyramidal regions to confine the output consensus error. A particle swarm optimization-based (PSO-based) algorithm is applied to compute the controller gains and optimize the volume of the hyperpyramids. The proposed methods are verified by the presented numerical case studies.

Novel Cellulose Nanocrystals-Based Polyurethane: Synthesis, Characterization and Antibacterial Activity.

As a new type of polymer, water-driven polyurethane (PU) has attracted increasing attention of researchers; however, with the popularization of its application, the following infection problems limit their applications, especially in the biomedical field. Herein, a series of novel cellulose nanocrystals (CNCs)-based PUs were first synthesized by chemical cross-linking CNCs with triblock copolymer polylactide-poly (ethylene glycol)-polylactide (CNC-PU). After covalent binding with tannic acid (TA-CNC-PU), the silver nanoparticles (Ag NPs) were further introduced into the material by a reduction reaction (Ag/TA-CNC-PU). Finally, the prepared serial CNCs-based PU nanocomposites were fully characterized, including the microstructure, water contact angle, water uptake, thermal properties as well as antibacterial activity. Compared with CNC-PU, the obtained TA-CNC-PU and Ag/TA-CNC-PU were capable of lower glass transition temperatures and improved thermal stability. In addition, we found that the introduction of tannic acid and Ag NPs clearly increased the material hydrophobicity and antibacterial activity. In particular, the Ag/TA-CNC-PU had a better antibacterial effect on E. coli, while TA-CNC-PU had better inhibitory effect on S. aureus over a 24 h time period. Therefore, these novel CNCs-based PUs may be more beneficial for thermal processing and could potentially be developed into a new class of smart biomaterial material with good antibacterial properties by adjusting the ratio of TA or Ag NPs in their structures.

Complete chloroplast genome sequencing of Job's tears (Coix L.): genome structure, comparative analysis, and phylogenetic relationships.

Job's tears, also known as adlay, is a valuable plant that has commonly been used in traditional Chinese medicine, as well as an edible food. Due to the lack of knowledge of its genetics and gaps in its evolutionary analysis, breeding of adlay has been hindered. Here, we report five complete chloroplast genomes of various species and varieties in the genus by Illumina sequencing, while their genome structure, comparative analysis, and phylogenetic relationships were conducted. Genome sizes ranged from 140,860 to 140,864 bp in length, GC contents were 38.43%, and genome architecture was of a typical quadripartite structure. We annotated 82～83 protein-coding genes and 46～47 non-coding RNA genes in each genome and they functionally associated with self-replication, photosynthesis, cytochrome synthesis and other unknown functions. Three codons that encoded tryptophan, arginine and leucine were used frequently at rates of 41.42, 37.98, and 32.28% respectively. The preferred codons consistently ended with A or T. A total of 146 simple sequence repeats (SSR), 9 insertions and deletions (InDels) and 143 single nucleotide polymorphisms (SNPs) were observed among genomes. The InDel and SNP variations were mostly distributed in intergenic regions. It confirmed that Coix, Sorghum, Saccharum, Zea, Tripsacum and Saccharum were closely genera and the genetic distance of Sorghum to Coix was closer than Zea to Coix. These results give us more insight into the evolution of Coix in a wide range of evolutionary studies.

[Progress in dual-responsive nanocarriers based on acid sensitivity for anticancer drug].

In order to achieve better tumor treatment, researchers have designed dual and multiple responsive smart nanocarriers in the tumor microenvironment. Among them, the research based on acid-sensitive dual-responsive nanocarriers is the most extensive and common one. Intelligent nanocarriers have initially achieved long circulation in body, effective accumulation in tumor cells, and controlled drug release in tumor microenvironment, with increased anti-tumor effect of drug and reduced damage to normal tissues. However, there are still many problems to be solved in current research, such as high price, complicated nanocarriers structure, and unclear mechanisms of drug delivery in the body, all hampering nanocarriers from clinical applications. This article introduces the progress of nanocarriers in recent years from the dual responsive aspects including acid-temperature, acid-magnetism, acid-redox, acid-enzyme, acid-light and acid-ultrasound, to provide reference for further clinical application of nanomedicine.

Downregulated miR-486-5p acts as a tumor suppressor in esophageal squamous cell carcinoma.

microRNAs (miRNAs/miRs) are crucial regulators of gene expression at the post-translational level through promoting mRNA degradation or the repression of translation of target genes. miRs have been confirmed to serve a dominant role in tumor biology. miR-486-5p has been ascertained to be involved in non-small-cell lung cancer, breast cancer and hepatocellular carcinoma; however, the expression and function of miR-486-5p in esophageal squamous cell carcinoma (ESCC) has yet to be elucidated. The present study aimed to analyze the expression levels of miR-486-5p in ESCC tissues and paired normal adjacent tissues, and determine the effects of miR-486-5p on esophageal cancer cells using MTT, wound scratch and apoptosis assays. The current results showed that miR-486-5p was significantly downregulated in ESCC specimens. Ectopic expression of miR-486-5p by synthetic mimics reduced cell proliferation and migration and induced increased cell apoptosis. The results indicated miR-486-5p may function as a tumor suppressor in ESCC. The present study demonstrated that miR-486-5p was downregulated in ESCC and served a anti-oncogene role in ESCC via affecting cellular migration.

Upregulated miR-193a-3p as an oncogene in esophageal squamous cell carcinoma regulating cellular proliferation, migration and apoptosis.

MicroRNAs (miRs) are small endogenous non-coding RNAs that play a vital role in carcinogenesis. miR-193a-3p has been described in multiple cancers. However, the function of miR-193a-3p in esophageal squamous cell carcinoma (ESCC) is still unclear. To explore the role of miR-193a-3p in ESCC, reverse transcription-quantitative polymerase chain reaction was used to evaluate the expression of miR-193a-3p in 48 paired ESCC and adjacent normal tissues. In addition, the impact of miR-193a-3p on cell proliferation, migration and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, wound scratch assay and flow cytometry, respectively. The results revealed that miR-193a-3p was upregulated in ESCC, compared with adjacent normal tissues. Downregulation of miR-193a-3p expression using a synthesized inhibitor suppressed cell proliferation and migration, and induced cell apoptosis, indicating that miR-193a-3p could be characterized as an oncogene in ESCC. In summary, the present study demonstrated that miR-193a-3p was upregulated in ESCC, where it plays a significant role by affecting cellular proliferation, migration and apoptosis.

EMSA and single-molecule force spectroscopy study of interactions between Bacillus subtilis single-stranded DNA-binding protein and single-stranded DNA.

In this article, interactions between Bacillus subtilis single-stranded DNA binding proteins (BsSSB) and single-stranded DNA (ssDNA) were systematically studied. The effect of different molar ratios between BsSSB and ssDNA on their binding modes was first investigated by electrophoretic mobility shift assays (EMSAs). It is found that a high molar ratio of BsSSB to ssDNA can produce BsSSB-ssDNA complexes formed in the mode of two proteins binding one 65-nt (nucleotide) ssDNA whereas a low molar ratio facilitates the formation of BsSSB-ssDNA complexes in the mode of one protein binding one 65-nt ssDNA. Furthermore, two binding modes are in dynamic equilibrium. The unbinding force of BsSSB-ssDNA complexes was measured quantitatively in solutions with different salt concentrations by using AFM-based single-molecule force spectroscopy (SMFS). Our results show that the unbinding force is about 10 pN higher at high salt concentration (0.5 M NaCl) than at low salt concentration (0.1 M NaCl) and the lifetime of BsSSB-ssDNA complexes at high salt concentration is twice as long as that at low salt concentration. These results indicate that more tightly packed BsSSB-ssDNA complexes can form at high salt (0.5 M NaCl) concentration. In addition, the results of EMSA show that ssDNA, which is bound to BsSSB, can dissociate from BsSSB in the presence of the cDNA strand, indicating the dynamic nature of BsSSB-ssDNA interactions.