779 research outputs found

    Comparisons of Different Instruments for Measuring Suspended Cohesive Sediment Concentrations

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    Laboratory experiments were conducted to compare the performances of four different instruments for measuring suspended cohesive sediment concentrations (SSCs). Among these instruments, two were different models of optical backscatter sensor (i.e., OBS3+ and OBS5+), one was an acoustic Doppler velocimeter (MicroADV), and the last was a laser infrared optical sensor developed at Hohai University, China (HHU-LIOS). Sediments collected from the Yangtze River Estuary and a commercially available kaolinite were selected to check the responses of these four instruments. They were placed in an aqueous solution, and the SSCs were changed within a range from about 10 mg/L to 30 g/L to demonstrate the effective measuring ranges for each instrument. For the kaolinite suspension, the results showed that the HHU-LIOS has a much larger linear response range (0.1 to 13 g/L) when compared with other devices (the MicroADV: 0.1 to 1.35 g/L; the OBS3+: 0.1 to 5 g/L; and the OBS5+: 0.1 to 1 g/L). For the sediment sample from the Yangtze River Estuary, the results showed that the HHU-LIOS has a much wider usable range (from 0.1 to 25 g/L), compared with those for the others. It also showed that a combination of using a HHU-LIOS for the quadratic increasing range up to 25 g/L and the OBS5+ for the clear decreasing output are able to measure the SSCs of the estuarine mud up to 50 g/L

    A linear matrix inequality (LMI) approach to robust H2 sampled-data control for linear uncertain systems

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    In this paper, we consider the H2 sampled-data control for uncertain linear systems by the impulse response interpretation of the H2 norm. Two H2 measures for sampled-data systems are considered. The robust optimal control procedures subject to these two H2 criteria are proposed. The development is primarily concerned with a multirate treatment in which a periodic time-varying robust optimal control for uncertain linear systems is presented. To facilitate multirate control design, a new result of stability of hybrid system is established. Moreover, the single-rate case is also obtained as a special case. The sampling period is explicitly involved in the result which is superior to traditional methods. The solution procedures proposed in this paper are formulated as an optimization problem subject to linear matrix inequalities. Finally, we present a numerical example to demonstrate the proposed techniques.published_or_final_versio

    Alphonsea glandulosa (Annonaceae), a new species from Yunnan, China

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    Development of specific RAPD markers for identifying albino tea cultivars ‘Qiannianxue’ and ‘Xiaoxueya’

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    Albino tea cultivars grow white leaves at low temperature which are valuable materials for processing green tea, but they develop green leaves in summer and autumn seasons. It is difficult to discriminate albino tea cuttings from the normal tea cuttings by leaf colour and plant morphological characteristics.Specific RAPD markers for identifying albino tea cultivars ‘Qiannianxue’ and ‘Xiaoxueya’ were developed in the present paper and they can be used in the authentication of the two albino tea cultivars. An amplified fragment (about 1500 bp) from Primer (S 12 (Sangon Biological Engineering Technology and Services Co., Ltd.) was identified in the albino teas and not from the widely cultivated cultivar; Fudingdabai

    Video Saliency Detection Using Object Proposals

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    In this paper, we introduce a novel approach to identify salient object regions in videos via object proposals. The core idea is to solve the saliency detection problem by ranking and selecting the salient proposals based on object-level saliency cues. Object proposals offer a more complete and high-level representation, which naturally caters to the needs of salient object detection. As well as introducing this novel solution for video salient object detection, we reorganize various discriminative saliency cues and traditional saliency assumptions on object proposals. With object candidates, a proposal ranking and voting scheme, based on various object-level saliency cues, is designed to screen out nonsalient parts, select salient object regions, and to infer an initial saliency estimate. Then a saliency optimization process that considers temporal consistency and appearance differences between salient and nonsalient regions is used to refine the initial saliency estimates. Our experiments on public datasets (SegTrackV2, Freiburg-Berkeley Motion Segmentation Dataset, and Densely Annotated Video Segmentation) validate the effectiveness, and the proposed method produces significant improvements over state-of-the-art algorithms

    The role of regulatory B cells on hepatocellular carcinoma progression

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    Poster PresentationCongress Theme: Translating Discoveries into Prevention and CuresPURPOSE: Regulatory B cells (Bregs) play important roles in autoimmune diseases, but their function in hepatocellular carcinoma (HCC) progression remains unclear. This study attempted to unveil the role of Bregs on HCC progression. EXPERIMENTAL DESIGN: This study examined the distribution of intrahepatic B cells and circulating Bregs population at the level of phenotypes as well as functionality in HCC patients. The mechanisms of Bregs regulating liver tumor cells were further explored in a series of in vitro and in vivo functional studies. RESULTS: The percentage of B cells at tumor margin region was significantly higher than that in tumor or non-tumor region. Increased intrahepatic B cells at tumor margin were positively associated with tumor invasive features and more tumor recurrence. Besides, HCC patients had a significant higher percentage of circulating Bregs than healthy people. Increased circulating Bregs were positively correlated with advanced tumor staging, tumor multiplicity and venous infiltration. Next, our in vivo study firstly revealed that human Bregs promoted HCC tumor growth independent of Tregs in SCID mice. The migration of Bregs into tumor in mice was further confirmed by in vivo imaging and histology. Finally, the molecular mechanism of Bregs promoted proliferation and migration of HCC cells was proved by direct cell-cell interaction via CD40/CD154 signaling in vitro. Coculture of Bregs and HCC cells induced CD40/CD154-dependent cytokines secretion. CONCLUSION: Human Bregs promoted HCC growth and invasiveness by interacting with HCC tumor cells through CD40/CD154 signaling pathway. Bregs might be both a prognostic marker and a therapeutic target for HCC.published_or_final_versio

    Soil-water interacting use patterns driven by Ziziphus jujuba on the Chenier Island in the Yellow River Delta, China

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    The determination of water use patterns of plants in a coastal ecosystem is critical to our understanding of local eco-hydrological processes and predicting trends in ecological succession under the background of global climate change. The water use patterns of Ziziphus jujuba, the dominant species on the Chenier Island in the Yellow River Delta, were examined following summer rainfall events. Stable oxygen isotope analysis was employed to analyze the effects of rainfall on the stable isotopic composition in potential water sources in Z. jujuba. The IsoSource model was used to estimate the contributions of potential water sources for xylem water in Z. jujuba. The results showed heavy rainfall could recharge both soil and groundwater but contributed little to the O-18 values in deep soil water (60-100cm) and groundwater. Light rainfall had an effect only on surface soil water (0-40cm). Z. jujuba mainly absorbed deep soil water on non-rainy days. Rainwater became the predominant water source for Z. jujuba during and immediately after heavy rainfall. Switching the plant's main water source between deep soil water and rainwater provided Z. jujuba with a competitive advantage and improved the water use efficiency of Z. jujuba in this coastal ecosystem
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