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921.
合成C5石油树脂催化剂的研究 总被引:1,自引:0,他引:1
研制了一种酸性离子溶液,它是一种新型的催化剂溶液,可广泛应用于均相催化.使用这种催化剂离子溶液催化合成C5石油树脂,研究了催化剂用量、温度和添加方式对聚合反应的影响. 相似文献
922.
Tatiana B. Eronina Valeriya V. Mikhaylova Natalia A. Chebotareva Kristina V. Tugaeva Boris I. Kurganov 《International journal of molecular sciences》2022,23(7)
Protein–protein interactions (PPIs) play an important role in many biological processes in a living cell. Among them chaperone–client interactions are the most important. In this work PPIs of αB-crystallin and glycogen phosphorylase b (Phb) in the presence of betaine (Bet) and arginine (Arg) at 48 °C and ionic strength of 0.15 M were studied using methods of dynamic light scattering, differential scanning calorimetry, and analytical ultracentrifugation. It was shown that Bet enhanced, while Arg reduced both the stability of αB-crystallin and its adsorption capacity (AC0) to the target protein at the stage of aggregate growth. Thus, the anti-aggregation activity of αB-crystallin increased in the presence of Bet and decreased under the influence of Arg, which resulted in inhibition or acceleration of Phb aggregation, respectively. Our data show that chemical chaperones can influence the tertiary and quaternary structure of both the target protein and the protein chaperone. The presence of the substrate protein also affects the quaternary structure of αB-crystallin, causing its disassembly. This is inextricably linked to the anti-aggregation activity of αB-crystallin, which in turn affects its PPI with the target protein. Thus, our studies contribute to understanding the mechanism of interaction between chaperones and proteins. 相似文献
923.
924.
Kamil Cebulski Katarzyna Nowiska Karolina Jabloska Hanna Romanowicz Beata Smolarz Piotr Dzigiel Marzenna Podhorska-Okow 《International journal of molecular sciences》2022,23(7)
Irisin is a myokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. FNDC5 and irisin levels have been poorly studied in the tumor tissues of breast cancer (BC). The aim of this study was to determine the levels of irisin expression in BC tissues and compare them to clinicopathological factors and Ki-67 and PGC-1α expression levels. Tissue microarrays (TMAs) with 541 BC tissues and 61 samples of non-malignant breast disease (NMBD; control) were used to perform immunohistochemical reactions. FNDC5 gene expression was measured in 40 BC tissue samples, 40 samples from the cancer margin, and 16 NMBD samples. RT-PCR was performed for the detection of FNDC5 gene expression. Higher irisin expression was found in BC patients compared to normal breast tissue. FNDC5/irisin expression was higher in patients without lymph node metastases. Longer overall survival was observed in patients with higher irisin expression levels. FNDC5/irisin expression was increased in BC tissues and its high level was a good prognostic factor for survival in BC patients. 相似文献
925.
Myeong Seong Sim Hye Jeong Kim Sang Hee Jo Chun Kim Il Yup Chung 《International journal of molecular sciences》2022,23(7)
Lysophosphatidylserine (LysoPS) is an amphipathic lysophospholipid that mediates a broad spectrum of inflammatory responses through a poorly characterized mechanism. Because LysoPS levels can rise in a variety of pathological conditions, we sought to investigate LysoPS’s potential role in airway epithelial cells that actively participate in lung homeostasis. Here, we report a previously unappreciated function of LysoPS in production of a mucin component, MUC5AC, in the airway epithelial cells. LysoPS stimulated lung epithelial cells to produce MUC5AC via signaling pathways involving TACE, EGFR, and ERK. Specifically, LysoPS- dependent biphasic activation of ERK resulted in TGF-α secretion and strong EGFR phosphorylation leading to MUC5AC production. Collectively, LysoPS induces the expression of MUC5AC via a feedback loop composed of proligand synthesis and its proteolysis by TACE and following autocrine EGFR activation. To our surprise, we were not able to find a role of GPCRs and TLR2, known LyoPS receptors in LysoPS-induced MUC5AC production in airway epithelial cells, suggesting a potential receptor-independent action of LysoPS during inflammation. This study provides new insight into the potential function and mechanism of LysoPS as an emerging lipid mediator in airway inflammation. 相似文献
926.
随着物联网通信计算需求激增,5G通信与边缘计算网络逐步成为新兴的高能耗负荷。针对5G边缘计算网络用电成本高的问题,提出了联合任务卸载与需求响应策略。所提策略基于任务卸载与基站储能单元充放电动作,在高电价时段联合优化计算、通信与储能资源分配或者牺牲部分时延性能以削减用电成本,在分时电价机制中为电网提供响应能力。针对优化目标为混合整数非线性规划问题,进一步提出结合网络场景划分的广义benders分解算法,将问题解耦为任务卸载决策主问题与充放电以及资源分配子问题,降低问题求解复杂度。仿真结果表明:相比于仅考虑任务卸载和仅考虑通信资源调度的响应策略,所提策略降低了用电成本并避免时延性能恶化。 相似文献
927.
随着第5代移动通信技术(5G通信)的迅速发展,5G基站数量不断增加,5G通信耗电量大、用电成本高的问题日益突出。为此,提出了考虑光伏和储能接入的5G基站光储系统优化配置方法,以提高5G基站运行的经济性。首先,考虑5G基站负荷情况和配电网分时电价,建立了5G基站光储系统的经济调度模型;然后,通过量子粒子群优化算法计算典型日内5G基站光储系统的最小综合成本,以此确定光伏和储能的最优接入容量;最后,通过算例证明合理配置光伏和储能容量可以提高5G基站系统的经济性。光伏和储能容量的配置受储能成本和峰谷电价差的影响较大,且光储系统所能带来的经济效益随峰谷电价差的增大和储能成本的降低而增大。 相似文献
928.
The different types of metal powder used for selective laser melting(SLM) process would cause distinct corrosion behavior due to the uniformity of the obtained microstructure.The SLM-produced Ti–5Cu alloy using atomized Ti–5Cu metal powder(SLMed Ti–5Cu) in this work reveals a relatively uniform microstructure with overwhelming acicular α/α′ phase and shows great advantages on corrosion resistance compared with the SLM-produced Ti–5Cu alloy using the mixture powder(SLMedM Ti–5Cu).The effect of the micro-galvanic cells decreases due to the undetectable Ti_2Cu phase in the microstructure of the SLMed Ti–5Cu.An apparent passivation behavior was observed for SLMed Ti–5Cu instead of severe pitting phenomenon for the SLMed-M Ti–5Cu.The charge transfer resistance of SLMed Ti–5Cu in this work is 10.09 ± 2.63 MΩ cm~2, which is significantly higher than that of SLMed-M Ti–5Cu(4.76 MΩ cm~2).The above result indicates the atomized Ti–5Cu powder plays an important role in the formation of the uniform microstructure of SLMed product, thereby enhancing its corrosion resistance in Hank's solution at 37 ℃. 相似文献
929.
为了达到项目驱动实践教学的目的,提出了基于项目驱动实践教学支撑系统的功能结构设计。该系统提出了对任务驱动的设计、建模和管理,在具体实现上,按分层结构组织程序,用XML文件描述功能元数据,以My SQL作为后台数据库,采用最新Java EE技术架构SSHJ(Struts 2+Spring+JPA+Hibernate),通过Activiti 5工作流技术实现任务建模与管理,并利用DWR技术改进交互体验。实践表明,该系统具有便于维护与扩展、使用方便等特点。 相似文献
930.
M5纤维的研究及应用 总被引:1,自引:0,他引:1
介绍了M5纤维的结构、物理性能、抗冲击性、阻燃性及其与其他几种高强高模纤维的性能对比,概述了M5纤维在复合材料、个体防护用品、防火产品、绳索和先进织物上的应用。 相似文献