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21.
Interferons are widely used platform therapies as disease-modifying treatment of patients with multiple sclerosis. Although interferons are usually safe and well tolerated, they frequently cause dermatological side effects. Here, we present a multiple sclerosis (MS) patient treated with interferon-β who developed new-onset psoriasis. Both her MS as well as her psoriasis finally responded to treatment with fumarates. This case illustrates that interferons not only cause local but also systemic adverse events of the skin. These systemic side effects might indicate that the Th17/IL-17 axis plays a prominent role in the immunopathogenesis of this individual case and that the autoimmune process might be deteriorated by further administration of interferons. In conclusion, we think that neurologists should be aware of systemic cutaneous side effects and have a closer look on interferon-associated skin lesions. Detection of psoriasiform lesions might indicate that interferons are probably not beneficial in the individual situation. We suggest that skin lesions may serve as biomarkers to allocate MS patients to adequate disease-modifying drugs.  相似文献   
22.
For the first time solar disinfection of liters of water containing wild Salmonella sp. and total coliforms was carried out in a compound parabolic collector (CPC) photoreactor at temperatures of almost 50 °C. Using surface water with high turbidity, this treatment was efficient in completely inactivating Salmonella sp. without regrowth during the subsequent 72 h of dark sterile storage. However if the solar treated water is poured in a non- sterile container, bacteria regrowth occurs even if 10 mg L−1 of H2O2 is added before the storage. On the other hand, 30 mg L−1 of H2O2 added when the irradiation started was completely depleted within 2 h and did not prevent bacterial regrowth during post-irradiation storage in non-sterile containers, demonstrating that storage of large volumes of water treated by solar irradiation was not optimal. Finally, total coliforms (Escherichia coli included) showed a far higher sensitivity than Salmonella sp. and demonstrated to be an inappropriate indicator for monitoring bacterial contamination in water during solar disinfection processes.  相似文献   
23.
河道整治特别是两岸堤防的新建、加高和加固等措施是提高河道防洪能力的主要工程手段,但是河道堤防在满足设计标准后,在发生设计频率洪水时,原来的洪水漫滩现象大大减少,这将增加下游的洪峰流量,洪峰时间也将提前,对下游的防洪有一定的不利影响。以松阳县松阴溪干流为例,通过河道非恒定流模型计算发现,松阴溪流域遭遇20年一遇洪水时,河道堤防整治后靖居口水文站处洪峰流量将增大5.3%,峰现时间提前0.9 h。  相似文献   
24.
介绍了南水北调中线京石段应急供水工程各类闸站负荷等级、主接线方式、供电保证概率分析计算等。首次利用相互独立事件的概率理论将供电保证率定性描述提升至定量描述,对丰富供配电系统设计理论,指导工程设计实践,提高供电保证率具有应用价值。  相似文献   
25.
该文根据实践经验总结了探查地下供水水泥管道的综合方法。文中介绍了管道布设的特点与探查工作的关系,探查工作的顺序和具体方法,强调了应注意的问题。  相似文献   
26.
This paper presents a supervisory control scheme based on hybrid systems theory and fuzzy events detection. The fuzzy event detector is a linguistic model, which synthesizes complex relations between process variables and process events incorporating experts' knowledge about the process operation. This kind of detection allows the anticipation of appropriate control actions, which depend upon the selected membership functions used to characterize the process under scrutiny. The proposed supervisory control scheme was successfully implemented for an oxichlorination reactor in a vinyl monomer plant. This implementation has allowed improvement of reactor stability and reduction of raw material consumption.  相似文献   
27.
Isolation is an effective method of reducing effects of seismic events on building structures. Steel-reinforced elastomeric isolator (SREI) is one kind of isolation system which is used extensively, but there are some problems associated with its use, such as cost and weight. Fiber-reinforced elastomeric isolator (FREI) has been developed in an attempt to solve the problems of high cost and heavy weight for SREI. In this study, mechanical properties for the SREI and the FREI are investigated. Systematic dynamic response analyses are performed for three different models such as a fixed based, an SREI based and an FREI based low-story building structures. Two-dimensional and three-dimensional dynamic response analysis results for each model are compared in terms of displacement, drift, acceleration and shear force in this study. In the two-dimensional dynamic response analysis, the SREI and the FREI based structures are proven to be the more effective isolation systems against seismic events by comparing with the fixed based one. As a result, the FREI has shown better isolation performances than that of the SREI. Furthermore, to extract the characteristics of the FREI on building structure resisting the seismic effects, two models of three-dimensional framed structure with fixed bases and FREI isolated bases are built, respectively. After the dynamic response analysis of these two structures subjected to bi-directional ground motions, the analyzed results are compared with each other. It is shown that the FREI could effectively absorb the seismic energy, and decreases the destructive effects acting on a building structure due to ground horizontal motions that could occur in an earthquake. This paper was recommended for publication in revised form by Associate Editor Seockhyun Kim Beom-Soo Kang received his B.S. in Mechanical Engineering from Pusan National University in 1981 and his M.S. in Aerospace Engineering from KAIST in 1983, Korea, respectively. He then received his Ph.D. from the University of California at Berkeley, USA, in 1990. Dr. Kang is currently a Professor at the Department of Aerospace Engineering at Pusan National University in Busan, Korea. His research interests include seismic isolation, materials processing, FEM and flexible forming technology. Tae-Wan Ku received his B.S., M.S. and Ph.D. in Aerospace Engineering from Pusan National University, Korea, in 1997, 1999 and 2003, respectively. Dr. Ku is currently a research professor at the Department of Aerospace Engineering at Pusan National University in Busan, Korea. His research interests include multi-stage deep drawing, flexible forming technology, and forming limit surface theory.  相似文献   
28.
本文对柴河水库在汛期可能遭遇的极端突发水文事件的类型作了初级预测,并设计了初步的预报调度方面的对应预案。  相似文献   
29.
以桥沟小流域为研究对象,利用该流域不同地貌部位的野外径流场及沟道水文站网观测资料,计算了不同场次降水的泥沙输移比,较为系统地研究了影响桥沟流域次降水泥沙输移比的水文要素。结果表明:土壤前期含水量、流域的降水过程特征、洪峰流量、径流量、水流含沙量是影响次降水泥沙输移比的主要水文要素;提出了表示降水、径流、泥沙对泥沙输移比影响的表征参数,即降水峰现系数、径流侵蚀力和泥沙相对容重。  相似文献   
30.
    
Accurately determining hydrodynamic force statistics is crucial for designing offshore engineering structures, including offshore wind turbine foundations, due to the significant impact of nonlinear wave–structure interactions. However, obtaining precise load statistics often involves computationally intensive simulations. Furthermore, the estimation of statistics using current practices is subject to ongoing discussion due to the inherent uncertainty involved. To address these challenges, we present a novel machine learning framework that leverages data-driven surrogate modeling to predict hydrodynamic loads on monopile foundations while reducing reliance on costly simulations and facilitate the load statistics reconstruction. The primary advantage of our approach is the significant reduction in evaluation time compared to traditional modeling methods. The novelty of our framework lies in its efficient construction of the surrogate model, utilizing the Gaussian process regression machine learning technique and a Bayesian active learning method to sequentially sample wave episodes that contribute to accurate predictions of extreme hydrodynamic forces. Additionally, a spectrum transfer technique combines computational fluid dynamics (CFD) results from both quiescent and extreme waves, further reducing data requirements. This study focuses on reducing the dimensionality of stochastic irregular wave episodes and their associated hydrodynamic force time series. Although the dimensionality reduction is linear, Gaussian process regression successfully captures high-order correlations. Furthermore, our framework incorporates built-in uncertainty quantification capabilities, facilitating efficient parameter sampling using traditional CFD tools. This paper provides comprehensive implementation details and demonstrates the effectiveness of our approach in delivering reliable statistics for hydrodynamic loads while overcoming the computational cost constraints associated with classical modeling methods.  相似文献   
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