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61.
Dr. Lalit N. Goswami Dr. Tyson J. Olds Dr. Terri G. Monk Dr. Quinn L. Johnson Dr. James P. Dilger Dr. Mohammed A. Shanawaz Dr. Satish S. Jalisatgi Dr. M. Frederick Hawthorne Dr. George R. Kracke 《ChemMedChem》2019,14(11):1108-1114
We synthesized a family of neuromuscular blocking agents (NMB) based on decamethonium, but containing a carborane cluster in the methylene chain between the two quaternary ammonium groups. The carborane cluster isomers o-NMB, m-NMB, and p-NMB were tested in animals for neuromuscular block and compared with agents used clinically: rocuronium and decamethonium. All three isomers caused reversible muscle weakness in mice as determined by grip strength and inverted screen tests, with a potency rank of p-NMB > rocuronium > decamethonium > m-NMB > o-NMB. The mechanism of action of the compounds was determined by using the in vitro rat phrenic nerve hemi-diaphragm preparation and electrophysiologic measurements in cells. Neostigmine reversed hemi-diaphragm weakness caused by the three isomers and rocuronium, but not succinylcholine. In electrophysiologic recordings of currents through acetylcholine receptor channels, the carborane compounds did not activate channel activity but did inhibit channel activation by acetylcholine. These results demonstrate that the carborane neuromuscular blocking agents are non-depolarizers in contrast to the depolarizing action of the parent compound. 相似文献
62.
对盐穴储气库系统密封性的测试与评价方法进行了详细介绍。测试方法选取原则、测试相关计算方法以及测试标准为储气库密封性测试的工程设计提供了详实的理论基础。 相似文献
63.
为了揭示供应商与承包商为主体的二级供应链中,两者间耦合作用条件下发生的供应中断对供应商最优决策及对承包商成本的影响机制,且剖析供应中断对承包商成本的冲击效应,以供应商存在高退出风险为研究对象,在仅知产量均值与方差条件下,运用Scarf提出的“极大极小值”鲁棒决策方法,通过设定不同决策情况下的供应链系统反馈,分析了不同退出标准情况下二级供应链的博弈过程。基于理论支撑下的鲁棒模型数值仿真结果得出:在退出标准α为100时,中间变量在290~350范围内,供应商存在最优决策,但承包商最优决策无法确定;与α为0时相比,在订货量达到一定状态,即α为140时,承包商成本增加了1.5%,表明承包商成本与供应商退出标准呈正相关,退出标准越高,对承包商成本造成的冲击效应越大。此研究结论为供应链初期不稳定且信息不完整条件下发生的供应中断影响机理提供了新的视角。 相似文献
64.
65.
随着三维CAD技术的发展,产品制造信息在三维模型和二维图纸之间的反复传递,严重影响了产品制造信息的正确、快速传递。基于三维产品制造信息技术,以采煤机防爆盖板为例,在UG NX10.0中建立了防爆盖板的三维模型并进行了三维标注,设计了加工工艺路线,规划了数控加工刀具轨迹,进行了加工仿真,验证了数控加工的正确性,在此基础上完成了采煤机防爆盖板的三维工艺式设计。该研究对基于模型定义的数字化设计与制造研究,实现制造业信息化具有重要意义。 相似文献
66.
Mohanalakshmi Sabapati Narahari N. Palei Ashok Kumar C.K. Ravindra Babu Molakpogu 《Drug development and industrial pharmacy》2019,45(4):577-586
The present study was aimed to develop Annona muricata fruit extract loaded solid lipid nanoparticles (SLNs) and explore its cytotoxic potential in vitro model of breast cancers. Extract loaded SLNs were successfully prepared by high-pressure homogenization followed by ultrasonication method and optimized using 23 full factorial design. The extract loaded SLNs were characterized using different parameters such as particle size (PS), % entrapment efficiency (EE), zeta potential (ZP) and % cumulative drug release (CDR). The SLNs formulation was optimized on the basis of software analysis with an overall desirability factor. The PS and %EE of the optimized formulation were found to be 134.8?nm and 83.26%, respectively. The optimized formulation showed a CDR of 79.83% up to 48?h. In vitro cytotoxicity efficacy of extract loaded SLNs was determined using MTT and Apoptosis assay and compared to that of a free extract. The SLNs showed a notable apoptotic effect and better efficacy to kill MCF7 cancer cells as compared to free extract. Thus, extract loaded SLNs could be an alternative dosage form which possibly controls therapeutic action with reducing side effect. 相似文献
67.
68.
Focusing on a process where a designer embeds herself in craftspeople’s workshops with the intention of ‘learning from inside’ and ‘making together’; this paper proposes pathways for considering collaboration between designers and craftspeople via digital fabrication and weaving. The tension of forces that make weaving possible, act as an analogy for this collaboration as well as providing the title of the project as ‘One Over, One Under’. The project proposes a mode of working and a spectrum of outcomes where the designer has a first-hand experience of production techniques, engages in a serious and continuous dialogue through making, and develops an intervention that also brings forth her own skill set (introducing digital fabrication and structural variations), thus transforming the conventions and boundaries between established roles and manufacturing techniques. An experiment that resulted in a series of objects considering both the technologies of production and the input of the designer, this process not only increases the potentials that crafts hold for the field of design, but it also offers possibilities of collaboration and a further articulation of the design act. 相似文献
69.
In many countries, distribution grid tariffs are being reformed to adapt to the new realities of an electricity system with distributed energy resources. In Europe, legislative proposals have been made to harmonize these reforms across country borders. Many stakeholders have argued that distribution tariffs are a local affair, while the European institutions argued that there can be spillovers to other countries, which could justify a more harmonized approach. In this paper, we quantify these spillovers in a simplified numerical example to give insight and an order of magnitude. We look at different scenarios, and find that the spillovers can be both negative and positive. To be able to quantify these effects, we developed a long-run market equilibrium model that captures the wholesale market effects of distribution grid tariffs. The problem is formulated as a non-cooperative game involving consumers, generating companies and distribution system operators in a stylized electricity market. 相似文献
70.
Soheil Khosrogorji Sepehr Soori Hossein Torkaman 《International Journal of Circuit Theory and Applications》2019,47(10):1645-1663
In this paper, a new design procedure for LLC converter has been introduced. In fact, this method is a computer-based design algorithm based on a numerical technique. In the process of designing, the value of the resonant element is obtained by solving the LLC converter fundamental equation. This converter will be controlled by using state feedback, such as output voltage variable. As a matter of fact, in a control system, the change of output voltage (because of load variation) will affect the switching frequency, so the output voltage will be tuned. In the designing process, the fundamental equations of LLC converter are obtained, and the value of the resonant elements is calculated. Also, a comparison analysis is carried out between the proposed and typical methods. The simulation is done to investigate the validity of the proposed method. Moreover, a prototype is manufactured, and the experimental test is done to evaluate its applicability. 相似文献