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In modern optical communication systems, signal light polarization state control technology can not only realize highspeed and large-capacity communication, but is also an indispensable part in the design of photonic integrated circuits. So far, the polarization extinction ratio (PER) is the main factor limiting the bandwidth of polarization control devices and it causes additional polarization loss in the whole communication system. Additionally, with the development of optical wireless communication technology in free space and underwater environment, the research on high-performance polarization control devices that suitable for visible light band has not been widely concerned. In this paper, a design concept for cross-talk free polarization control devices based on coupled mode theory has been illustrated, and several devices (including polarization splitters, polarization converters) have been given. Moreover, the design scheme and technical difficulties of polarization control devices in blue and green light band have also been evaluated.

In this paper, a quasi-omnidirectional transmitter is proposed and demonstrated for underwater wireless optical communication (UWOC) using the photoluminescence of perovskite quantum dots (QDs). The proposed transmitter, without complex driving circuits, is compact and reliable thanks to the lens-free design. The system performance is tested in a 50-m swimming pool with a water attenuation coefficient of 0.38 dB/m. The maximum data rates of on-off-keying (OOK) signals over 10-m and 20-m transmission distances can reach 60 Mbps and 40 Mbps, respectively. When four clients are adopted in a code division multiple access (CDMA) based UWOC network, the maximum data rates of each client can reach 10 Mbps and 7.5 Mbps over 10-m and 20-m underwater channels, respectively. The system can meet the requirements of the last meter end-user access in the Internet of underwater things (IoUT) and underwater optical cellular network systems.

In this research work, a Water-Jet catamaran HUSTER-30 is used as a case study to investigate the modeling and system identification of water-jet vessels. There is a natural phenomenon of the water-jet vessels, which is that the vessel cannot go straight with zero steering angle even under absolutely calm water conditions. Identifying the parameters of the water-jet vessel model and guaranteeing the identified parameters cover a wide range of maneuvering is investigated in this paper. The nonlinear asymmetric 3 Degree of Freedom (DOF) model considering water-jet system assembly error and the external force generated by the effect of outlet water flows is established. Moreover, a constrained multi-step prediction (CMSP) method is proposed in this paper to identify parameters of the nonlinear model. A series of experiments are conducted to identify the parameters, and the prediction results demonstrate that the asymmetric model has better performance than the symmetric model. Also, the identified results demonstrate that the parameters identified by the CMSP method have a more accurate prediction than the LS method in a wide range of maneuvering. The future work will focus on optimizing the proposed method and using the identified model for controller design and simulation study.

Colorectal cancer (CRC) is one of the most common carcinomas throughout the world. Although the diagnostic and therapeutic strategies have made some progression in the treatment of CRC patients, the mortality of CRC remains relatively high. Hence, it is an urgency to find out the detailed mechanisms of how CRC occurs.LncRNA Sox2ot expression was explored in CRC tissues and cell lines by using quantitative real-time PCR (qRT-PCR). Cell proliferation, migration and invasion ability was measured following downregulated expression of lncRNA Sox2ot by siRNA in CRC cells. Furthermore, western blot was used to detected the expression of Cyclin B1, Cdc 25C, N-cadherin, and E-cadherin in si-Sox2ot transfected CRC cells.We found that lncRNA Sox2ot was increased in CRC tissues and cell lines. High expression of Sox2ot was associated with the progression of CRC patients. Decreased Sox2ot expression inhibited the proliferation capacity and caused cell cycle arrested in G0/G1 phase in CRC cells. The key cell cycle regulators Cyclin B1 and Cdc 25C were consistently downregulated by knockdown of Sox2ot. Furthermore, knockdown of Sox2ot suppressed cell migration and invasion and decreased the expression of mesenchymal protein N-cadherin, while it increased the expression of epithelial protein E-cadherin in CRC cells.LncRNA Sox2ot could promoted CRC cell proliferation and motility and associated with the outcome of CRC patients, suggesting Sox2ot could serve as a potential therapeutic target in the treatment of CRC.

In continuation of our endeavor to develop and characterize the high performance polypropylene composites and their toughening master batches (TMBs), we report here the melt rheological properties of toughened polypropylene with balanced rigidity (TRPP). The relations of shear stress (τ), shear rate , apparent viscosity (ηa), temperature (T) and compositions of TRPPs were systematically investigated. Experimental data revealed that under ordinary shear flow conditions, the TRPP melts showed a pseudo-plastic feature. Based on the complexity of the melt flow of the blended poly-component/multiphase polymer system and together with our experimental and related literature results, the relationship between ηa and T for blended polymer melts was recommended to be expressed by the equation: log ηa = α0 + α1/T, where α1 was defined as the temperature coefficient of apparent viscosity. The relationship between τ and can be expressed by the equation: , and the exponent n is decreased as τ increasing. At a given τ or , the ηa of TRPPs decreased with ethylene-propylene to styrene-butadiene elastomer ratios from 20/80 to 100/0, increased with total elastomer content in TRPP and decreased with elastomer amount in TMB increasing. The manner of changes in ηa with compositions were not affected by the τ or T. Copyright © 2001 John Wiley & Sons, Ltd.

The creA genes of two plant pathogenic fungi, the gibberellin-producing rice pathogen Gibberella fujikuroi and the gray mold Botrytis cinerea, were isolated and characterized. The deduced amino acid sequences of both glucose repressors are 64% identical to each other and 59% (G. fujikuroi) and 61% (B. cinerea) identical to the CreA protein of Aspergillus nidulans. The zinc finger regions of the Gibberella and Botrytis CreA proteins shared 98% identity with the corresponding zinc finger region of the A. nidulans protein, and studies by complementation of a creA null mutant of A. nidulans showed that the proteins are functional homologues of A. nidulans CreA. Northern blot analysis revealed that creA transcript levels are independent of the carbon source in both fungi.