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961.
962.
塔里木灌区水库群实时调度研究 总被引:1,自引:0,他引:1
为缓和塔里木灌区引水与塔里木河的综合治理这一矛盾,以大系统分解协调技术与动态规划相结合的方法为基础建立了适合本灌区的自适应实时调度模型。为灌区水库实际控制应用提供了理论依据,对塔河的治理具有重要的现实意义。 相似文献
963.
超宽带(Ultra-Wideband,UWB)技术在室内外定位中应用广泛,针对传统多基站定位方案的局限性,提出了一种基于超宽带信号到达相位差(Ultra-Wideband Phase Difference of Arrival,UWB-PDOA)的少基站自适应定位系统。该系统利用UWB-PDOA技术和基于ESP32信号强度的权重自适应定位技术,大幅降低了对环境部署的依赖性,提高了定位的精度和稳定性。结合环境先验信息和目标高度的先验知识,构建了先验知识库,采用自适应定位技术,利用多个传感器的信息来调整对不同定位基站的置信度权重,进一步提高了定位精度和鲁棒性。实验结果表明,所提出的系统在视距(Line of Sight,LOS)和非视距(Non Line of Sight,NLOS)环境下都具有较高的定位精度和稳定性,并且仅需要不超过3个基站便可以满足室内环境定位的需求。 相似文献
964.
965.
定义了描述信号分离状态的一种测度,并在认真分析相关固定步长和变步长EASI算法的基础上。提出了一种新的步长自适应等变化自适应(EASI)算法。该算法步长是基于分离状态的。其学习速率由信号的分离程度自适应地选取。因而能很好地解决收敛速度和稳态误差之间的矛盾。计算机仿真结果与理论分析相一致,证实了该算法明显优于传统的EASI算法. 相似文献
966.
Nadire
zenver Onat Kadioglu Yujie Fu Thomas Efferth 《International journal of molecular sciences》2022,23(3)
Pigeon Pea (Cajanus cajan (L.) Millsp.) is a common food crop used in many parts of the world for nutritional purposes. One of its chemical constituents is cajanin stilbene acid (CSA), which exerts anticancer activity in vitro and in vivo. In an effort to identify molecular targets of CSA, we performed a kinome-wide approach based on the measurement of the enzymatic activities of 252 human kinases. The serine-threonine kinase WNK3 (also known as protein kinase lysine-deficient 3) was identified as the most promising target of CSA with the strongest enzymatic activity inhibition in vitro and the highest binding affinity in molecular docking in silico. The lowest binding affinity and the predicted binding constant pKi of CSA (−9.65 kcal/mol and 0.084 µM) were comparable or even better than those of the known WNK3 inhibitor PP-121 (−9.42 kcal/mol and 0.123 µM). The statistically significant association between WNK3 mRNA expression and cellular responsiveness to several clinically established anticancer drugs in a panel of 60 tumor cell lines and the prognostic value of WNK3 mRNA expression in sarcoma biopsies for the survival time of 230 patients can be taken as clues that CSA-based inhibition of WNK3 may improve treatment outcomes of cancer patients and that CSA may serve as a valuable supplement to the currently used combination therapy protocols in oncology. 相似文献
967.
The advent of cancer therapeutics brought a paradigm shift from conventional therapy to precision medicine. The new therapeutic modalities accomplished through the properties of nanomaterials have extended their scope in cancer therapy beyond conventional drug delivery. Nanoparticles can be channeled in cancer therapy to encapsulate active pharmaceutical ingredients and deliver them to the tumor site in a more efficient manner. This review enumerates various types of nanoparticles that have entered clinical trials for cancer treatment. The obstacles in the journey of nanodrug from clinic to market are reviewed. Furthermore, the latest developments in using nanoparticles in cancer therapy are also highlighted. 相似文献
968.
Henan Guo Yucui Tong Junhao Cheng Zaheer Abbas Zhongxuan Li Junyong Wang Yichen Zhou Dayong Si Rijun Zhang 《International journal of molecular sciences》2022,23(3)
Recently, the drawbacks arising from the overuse of antibiotics have drawn growing public attention. Among them, drug-resistance (DR) and even multidrug-resistance (MDR) pose significant challenges in clinical practice. As a representative of a DR or MDR pathogen, Staphylococcus aureus can cause diversity of infections related to different organs, and can survive or adapt to the diverse hostile environments by switching into other phenotypes, including biofilm and small colony variants (SCVs), with altered physiologic or metabolic characteristics. In this review, we briefly describe the development of the DR/MDR as well as the classical mechanisms (accumulation of the resistant genes). Moreover, we use multidimensional scaling analysis to evaluate the MDR relevant hotspots in the recent published reports. Furthermore, we mainly focus on the possible non-classical resistance mechanisms triggered by the two important alternative phenotypes of the S. aureus, biofilm and SCVs, which are fundamentally caused by the different global regulation of the S. aureus population, such as the main quorum-sensing (QS) and agr system and its coordinated regulated factors, such as the SarA family proteins and the alternative sigma factor σB (SigB). Both the biofilm and the SCVs are able to escape from the host immune response, and resist the therapeutic effects of antibiotics through the physical or the biological barriers, and become less sensitive to some antibiotics by the dormant state with the limited metabolisms. 相似文献
969.
Gae-Baik Kim Jeong Min Lee Duc Long Nguyen Joonseok Lee Young-Pil Kim 《International journal of molecular sciences》2022,23(3)
Activity-based monitoring of cell-secreted proteases has gained significant interest due to the implication of these substances in diverse cellular functions. Here, we demonstrated a cell-based method of monitoring protease activity using fluorescent cell-permeable peptides. The activatable peptide consists of anionic (EEEE), cleavable, and cationic sequences (RRRR) that enable intracellular delivery by matrix metalloproteinase-2 (MMP2), which is secreted by living cancer cells. Compared to HT-29 cells (MMP2-negative), HT-1080 cells (MMP2-positive) showed a strong fluorescence response to the short fluorescent peptide via cell-secreted protease activation. Our approach is expected to find applications for the rapid visualization of protease activity in living cells. 相似文献