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Offshore jacket platforms are widely used for oil and gas extraction as well as transportation in shallow to moderate water depth. Tubular cross-sectional elements are used to construct offshore platforms. Tubular cross sections impart higher resistance against hydrodynamic forces and have high torsional rigidity. During operation, the members can be partially or fully damaged due to lateral impacts. The lateral impacts can be due to ship collisions or through the impact of falling objects. The impact forces can weaken some members that influence the overall performance of the platform. This demonstrates an urgent need to develop a framework that can accurately forecast dent depth as well as dent angle of the affected members. This study investigates the use of an adaptive metaheuristics algorithm to provide automatic detection of denting damage in an offshore structure. The damage information includes dent depth and the dent angle. A model is developed in combination with the percentage of the dent depth of the damaged member and is used to assess the performance of the method. It demonstrates that small changes in stiffness of individual damaged bracing members are detectable from measurements of global structural motion.  相似文献   
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Integrin-mediated cell-matrix interactions play an important role in osteogenesis. Here, we constructed a novel osteoinductive fibronectin matrix protein (oFN) for bone tissue engineering, designed to combine the integrin-binding modules from fibronectin (iFN) and a strong osteoinductive growth factor, bone morphogenetic protein-2. Compared with iFN, the purified oFN matrix protein caused a significant increase in cell adhesion and osteogenic differentiation of pre-osteoblast MC3T3-E1 cells (p < 0.05).  相似文献   
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Fibronectin (FN) contributes to cell adhesion, proliferation, and differentiation in various cell types. To enhance the activity of fibronectin at the sites of focal adhesion, we engineered a novel recombinant fibronectin (FNIII10) fragment connected to the peptide amphiphile sequence (PA), LLLLLLCCCGGDS. In this study, the effects of FNIII10-PA on rat mesenchymal stem cells (rMSCs) were compared with those of FNIII10. FNIII10-PA showed the prominent protein adhesion activity. In addition, FNIII10-PA showed a significantly higher effect on adhesion, proliferation, and differentiation of rMSCs than FNIII10. Taken together, the FNIII10-containing self-assembled sequence enhanced rMSCs adhesion, proliferation, and differentiation.  相似文献   
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With the aim of reforming the control system of the levels of deaerator and condenser of a 200 MW thermal power unit, a multivariable fuzzy PID control system was proposed and has been used to practice. The novel control system has worked well since it was put into operation in March 1997.  相似文献   
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赵苏晋 《电源世界》2011,(7):42-44,41
阀控蓄电池的广泛使用对于在线监测是非常重要的课题。本文介绍了以LEM公司蓄电池传感器Sentinel模块为基础的蓄电池在线监测硬件平台的构成,并介绍了基于ARM9的蓄电池在线监测主机,现场进行了整机联调,给出了测试结果。实验证明该平台可以应用于蓄电池在线监测。  相似文献   
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Self‐assembled nanoaggregates co‐encapsulating doxorubicin (DOX) and oligonucleotide are prepared for dual‐responsive breakdown of the nanostructure with complete disappearance characteristics. Four‐arm poly(ethylene glycol) is co‐conjugated with DOX and anti‐bcl‐2 oligonucleotide with reducible linkers and acid‐cleavable linkers, respectively. The conjugate is hydrophobically self‐assembled into nanoaggregates in aqueous solution. Elemental scanning of the nanoaggregates reveals their core–shell structure with DOX and oligonucleotide located at the core and the shell, respectively. The tracking of size modulation suggests the complete disappearance of the particles under reducing conditions and the liberation of oligonucleotide at low pH, which is confirmed by dynamic light scattering and electron microscopy. The release of DOX and oligonucleotide is controlled by the pH and the reducing potential of the medium, and most of the drug and DNA are released in 24 h. The released fractions are analyzed by reversed‐phase chromatography, which indicates facile cleavage of DOX and oligonucleotide from the carriers. The nanoaggregates with both DOX and oligonucleotide show the lowest IC50 value when a cytotoxicity assay is performed against A549 cells. Apoptosis assay also confirms that cells treated with the nanoaggregates having both DOX and oligonucleotide show higher fluorescence intensity of antiapoptotic antibody than native DOX.  相似文献   
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The solar radiation model SRAD was applied to a Mediterranean mountainous environment in southern California for estimating land surface temperature (LST). The simulated SRAD LST results were compared with high- and meso-resolution satellite-based LST data at daily, monthly and annual temporal scales to identify potential ways of improving the LST accuracy in either the SRAD or satellite-based approaches. It was found that mean monthly and annual LST from SRAD closely matched the MODIS LST observations (but for the fact they were from 0.7 to 1.5 °C lower) while the daily LST from SRAD agreed less well with ASTER observations and were 2.1 °C and 4.8 °C higher for 01/23/05 and 07/21/06, respectively. High mountainous, steep and south/north facing slopes resulted in large discrepancies in LST estimates and the winter LST estimates are more sensitive to terrain factors and their associated land use/cover characteristics than the summer estimates. It is therefore suggested that vertically variable elevation lapse rates, spatially distributed surface albedo and leaf area index for the time-specific simulations that represent the heterogeneity of land surface characteristics be used in SRAD inputs. The results also show how instantaneous model outputs rather than lumped average daily outputs offer better comparisons with satellite based data as well.  相似文献   
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Low-density lipoprotein receptor-related protein 5 (LRP5) has been studied as a co-receptor for Wnt/β-catenin signaling. However, its role in the ischemic myocardium is largely unknown. Here, we show that LRP5 may act as a negative regulator of ischemic heart injury via its interaction with prolyl hydroxylase 2 (PHD2), resulting in hypoxia-inducible factor-1α (HIF-1α) degradation. Overexpression of LRP5 in cardiomyocytes promoted hypoxia-induced apoptotic cell death, whereas LRP5-silenced cardiomyocytes were protected from hypoxic insult. Gene expression analysis (mRNA-seq) demonstrated that overexpression of LRP5 limited the expression of HIF-1α target genes. LRP5 promoted HIF-1α degradation, as evidenced by the increased hydroxylation and shorter stability of HIF-1α under hypoxic conditions through the interaction between LRP5 and PHD2. Moreover, the specific phosphorylation of LRP5 at T1492 and S1503 is responsible for enhancing the hydroxylation activity of PHD2, resulting in HIF-1α degradation, which is independent of Wnt/β-catenin signaling. Importantly, direct myocardial delivery of adenoviral constructs, silencing LRP5 in vivo, significantly improved cardiac function in infarcted rat hearts, suggesting the potential value of LRP5 as a new target for ischemic injury treatment.  相似文献   
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