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101.
Yong Pan Chen Zhu Wen Bin Zeng Pei Fu Chi Chen Bao Ming Xu Zhong Feng Gao 《Chembiochem : a European journal of chemical biology》2021,22(24):3431-3436
Rapid and sensitive point-of-care testing (POCT) is an extremely critical mission in practical applications, especially for rigorous military medicine, home health care, and in the third world. Here, we report a visual POCT method for adenosine triphosphate (ATP) detection based on Taylor rising in the corner of quadratic geometries between two rod surfaces. We discuss the principle of Taylor rising, demonstrating that it is significantly influenced by contact angle, surface tension, and density of the sample, which are controlled by ATP-dependent rolling circle amplification (RCA). In the presence of ATP, RCA reaction effectively suppresses Taylor-rising behavior, due to the increased contact angle, density, and decreased surface tension. Without addition of ATP, untriggered RCA reaction is favorable for Taylor rising, resulting in a significant height. With this proposed method, visual sensitive detection of ATP without the aid of other instruments is realized with only a 5 μL droplet, which has good selectivity and a low detection limit (17 nM). Importantly, this visual method provides a promising POCT tool for user-friendly molecular diagnostics. 相似文献
102.
为了系统地评价胸腺五肽作为辅助药物治疗各种肺癌的疗效及其对机体免疫功能的影响,利用电子检索收集有关胸腺五肽联合放疗或化疗方案治疗肺癌的临床随机对照试验文献,对符合纳入标准的文献,采用RevMan5.3 软件进行系统评价。最终共纳入文献 9 篇,总样本量 784 例。Meta 分析结果表明,胸腺五肽作为辅助药物治疗各种肺癌提高总有效率的差异无统计学意义[OR = 1.44, 95%CI(0.99, 2.10), P =0.06 > 0.05]。在对免疫功能的影响方面,胸腺五肽的使用显著增高外周血中的 CD3+ 细胞水平[OR = 5.88, 95% CI(2.34, 9.42), P =0.001],CD4+ 细胞水平也显著上升[OR =8.32, 95%CI(5.22, 11.42), P < 0.00001] , CD4+ /CD8+比值也有明显的提高[OR = 0.38, 95% CI(0.18, 0.59), P=0.0002],但 CD8+ 细胞水平的差异无统计学意义[OR =-3.12, 95% CI ( -9.02, 2.79), P >0.05]。总的来说,本研究在一定程度上反映了在辅助治疗肺癌方面,胸腺五肽能显著提高外周血中的 CD3+ 细胞水平、CD4+ 细胞水平、CD4+/CD8+ 比值。而对于治疗的有效率、CD8+ 细胞水平,差异无统计学意义。 相似文献
103.
104.
Fei Xu Xiangli Shi Qingzhu Zhang Wenxing Wang 《International journal of molecular sciences》2015,16(8):18714-18731
The chlorothiophenoxy radicals (CTPRs) are key intermediate species in the formation of polychlorinated dibenzothiophenes/thianthrenes (PCDT/TAs). In this work, the formation of CTPRs from the complete series reactions of 19 chlorothiophenol (CTP) congeners with H and OH radicals were investigated theoretically by using the density functional theory (DFT) method. The profiles of the potential energy surface were constructed at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. The rate constants were evaluated by the canonical variational transition-state (CVT) theory with the small curvature tunneling (SCT) contribution at 600–1200 K. The present study indicates that the structural parameters, thermal data, and rate constants as well as the formation potential of CTPRs from CTPs are strongly dominated by the chlorine substitution at the ortho-position of CTPs. Comparison with the study of formation of chlorophenoxy radicals (CPRs) from chlorophenols (CPs) clearly shows that the thiophenoxyl-hydrogen abstraction from CTPs by H is more efficient than the phenoxyl-hydrogen abstraction from CPs by H, whereas the thiophenoxyl-hydrogen abstraction from CTPs by OH is less impactful than the phenoxyl-hydrogen abstraction from CPs by OH. Reactions of CTPs with H can occur more readily than that of CTPs with OH, which is opposite to the reactivity comparison of CPs with H and OH. 相似文献
105.
Yanlong Shi Xiaojuan Feng Haiyu Guan Jiahua Zhang Zhongai Hu 《International Journal of Hydrogen Energy》2021,46(12):8557-8566
Constructing high-efficient and nonprecious electrocatalysts is of primary importance for improving the efficiency of water splitting. Herein, a novel sunflower plate-like NiFe2O4/CoNi–S nanosheet heterostructure was fabricated via facile hydrothermal and electrodeposition methods. The as-fabricated NiFe2O4/CoNi–S heterostructure array exhibits remarkable bifunctional catalytic activity and stability toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline media. It presents a small overpotential of 219 mV and 149 mV for OER and HER, respectively, to produce a current density of 10 mA cm?2. More significantly, when the obtained electrodes are used as both the cathode and anode in an electrolyzer, a voltage of 1.57 V is gained at 10 mA cm?2, with superior stability for 72 h. Such outstanding properties are ascribed to: the 3D porous network structure, which exposes more active sites and accelerates mass transfer and gas bubble emission; the high conductivity of CoNi–S, which provides faster charge transport and thus promotes the electrocatalytic reaction of the composites; and the effective interface engineering between NiFe2O4 (excellent performance for OER) and CoNi–S (high activity for HER), which leads to a shorter transport pathway and thus expedites electron transfer. This work provides a new strategy for designing efficient and inexpensive electrocatalysts for water splitting. 相似文献
106.
汾西矿务局水峪矿部分工作面现已面临带压开采问题,受下伏奥陶系灰岩水害影响,工作面安全回采过程中的防治水工作难度增加,尤其是带压开采工作面底板灰岩水的有效探测变得异常紧迫与重要。为了解决底板带压开采工作面富水区的探测问题,水峪矿引入了并行电透视技术,并对相应工作面进行了探测应用。并行电透视技术相对于传统音频电透视技术具有仪器智能化控制发射接收切换、一发射点并行对应多接收点、仪器智能快速高效跑极施工的3项技术优势,可体现应用现场施工高效、实际探测效果可靠的技术特点。经过对并行电透视技术及探测应用效果分析研究,证明该方法技术领先,现场施工高效,实际探测结果可靠,实用性强。 相似文献
107.
108.
摘要:为了提高多机器人行为最优决策控制中强化学习的效率和收敛速度,研究了多机器人的分布式马尔科夫建模与控制策略。根据机器人有限感知能力设计了个体 协同感知触发函数,机器人个体从环境观测结果计算个体 协同触发响应概率,定义一次触发过程后开始计算联合策略,减少机器人间通讯量和计算资源。引入双学习率改进Q学习算法,并将该算法应用于机器人行为决策。仿真实验结果表明,当机器人群组数量在20左右时,本文算法的协同效率较高,单位时步比为1085 0。同时距离调节参数η对机器人协同搜索效率有影响,当η=0008时,所需的移动时步比和平均移动距离都能达到最小值。通过双学习率的引入,该算法较基于环境模型的强化学习算法具有更高的学习效率和适用性,平均性能提升35%,对于提高多机器人自主协同能力具有较高的理论意义及应用价值。 .txt 相似文献
109.
110.
Shanquan Chen Sicong Wei Fei Jin Shanming Ke Xierong Zeng Lang Chen Chuanwei Huang 《Ceramics International》2018,44(12):13695-13698
From the perspectives of scientific researches and practical applications, it is desirable to explore high operating temperature ferromagnetic films. The effect of biaxial strain on magnetic properties of (110)-oriented La0.7Sr0.3MnO3 films was studied. High quality La0.7Sr0.3MnO3 films were grown on (110)-oriented perovskite single crystal substrates using pulsed laser deposition, varying substrate-induced misfit strains from ??2.27–0.75%. A remarkable enhancement of Curie temperature has been achieved for (110)-oriented La0.7Sr0.3MnO3 films clamped with small misfit strains (i.e., grown on LAST (110)). The enhanced Curie temperature of (110)-oriented La0.7Sr0.3MnO3 films could be attributed to the misfit strain between the films and the underlying substrates and may have technological implication for applications at high temperature environments. 相似文献