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After angiogenesis-activated embryonic and early postnatal vascularization, endothelial cells (ECs) in most tissues enter a quiescent state necessary for proper tissue perfusion and EC functions. Notch signaling is essential for maintaining EC quiescence, but the mechanisms of action remain elusive. Here, we show that microRNA-218 (miR-218) is a downstream effector of Notch in quiescent ECs. Notch activation upregulated, while Notch blockade downregulated, miR-218 and its host gene Slit2, likely via transactivation of the Slit2 promoter. Overexpressing miR-218 in human umbilical vein ECs (HUVECs) significantly repressed cell proliferation and sprouting in vitro. Transcriptomics showed that miR-218 overexpression attenuated the MYC proto-oncogene, bHLH transcription factor (MYC, also known as c-myc) signature. MYC overexpression rescued miR-218-mediated proliferation and sprouting defects in HUVECs. MYC was repressed by miR-218 via multiple mechanisms, including reduction of MYC mRNA, repression of MYC translation by targeting heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), and promoting MYC degradation by targeting EYA3. Inhibition of miR-218 partially reversed Notch-induced repression of HUVEC proliferation and sprouting. In vivo, intravitreal injection of miR-218 reduced retinal EC proliferation accompanied by MYC repression, attenuated pathological choroidal neovascularization, and rescued retinal EC hyper-sprouting induced by Notch blockade. In summary, miR-218 mediates the effect of Notch activation of EC quiescence via MYC and is a potential treatment for angiogenesis-related diseases., Graphical abstract, Endothelial cell (EC) quiescence is important for vessel homeostasis and function, but the mechanism remains elusive. Han and colleagues report that miR-218 mediates the effect of Notch activation on promoting EC quiescence via repressing MYC, which holds potential in the treatment of angiogenesis-related diseases.

This paper presents adaptive methods to solve the synchronization problems of dynamic complex networks. Firstly, a complex network model is designed. Then, in order to achieve strong and weak synchronization, synchronization controllers and adaptive laws are designed. The adaptive laws are used for the renewal of unknown parameters, and the synchronization controller makes its error value in a small range. Then the Lyapunov function is used to prove the theory, and the simulation is used to prove the practice. Both results show that the proposed method can achieve strong synchronization and weak synchronization for nonlinear complex networks.

For a class of complex networks with continuous time-varying state-dependent disturbances, adaptive coupling adjustment methods are developed to solve the problem of robust general synchronization in this paper. The adaptive schemes aim to estimate unknown state-dependent factors and constant ranges. Then, coupling adjustment strategies are constructed based on the estimations to compensate for the effects of disturbances. Under the influence of continuous state-dependent disturbances, synchronization results are obtained by using the adaptive method combined with Lyapunov function. Simulation results verify the effectiveness of the proposed method.

Inflammatory leukocytes infiltration is orchestrated by mechanisms involving chemokines, selectins, addressins and other adhesion molecules derived from endothelial cells (ECs), but how they respond to inflammatory cues and coordinate leukocyte transmigration remain elusive. In this study, using hepatic ischemia/reperfusion injury (HIRI) as a model, we identified that endothelial Notch activation was rapidly and dynamically induced in liver sinusoidal endothelial cells (LSECs) in acute inflammation. In mice with EC-specific Notch activation (NICeCA), HIRI induced exacerbated liver damage. Consistently, endothelial Notch activation enhanced neutrophil infiltration and tumor necrosis factor (TNF)-α expression in HIRI. Transcriptome analysis and further qRT-PCR as well as immunofluorescence indicated that endomucin (EMCN), a negative regulator of leukocyte adhesion, was downregulated in LSECs from NICeCA mice. EMCN was downregulated during HIRI in wild-type mice and in vitro cultured ECs insulted by hypoxia/re-oxygenation injury. Notch activation in ECs led to increased neutrophil adhesion and transendothelial migration, which was abrogated by EMCN overexpression in vitro. In mice deficient of RBPj, the integrative transcription factor of canonical Notch signaling, although overwhelming sinusoidal malformation aggravated HIRI, the expression of EMCN was upregulated; and pharmaceutical Notch blockade in vitro also upregulated EMCN and inhibited transendothelial migration of neutrophils. The Notch activation-exaggerated HIRI was compromised by blocking LFA-1, which mediated leukocyte adherence by associating with EMCN. Therefore, endothelial Notch signaling controls neutrophil transmigration via EMCN to modulate acute inflammation in HIRI.

This paper presents the design and analysis of high performance flat-type linear permanent magnet gears. A salient pole mover structure and a simple scheme of pole shift are proposed. Totally thirteen topologies (including those of the conventional topology and the twelve new topologies) with different mover structures are given. The corresponding prototypes with a gear ratio of −5.5:1 are optimally designed and comparatively analyzed with 2-D finite element analysis. The new prototypes have, more or less, improvement in thrust force performance and structure strength with the same usage of sintered NdFeB permanent magnets. Among them, five representative prototypes are analyzed in detail, in aspects of magnetic field distribution, flux density in airgaps, force-position characteristic and on-load thrust force analysis. Results indicate that the salient pole permanent magnet movers and the pole shift scheme are effective to improve the transmission force and the structure strength.

When a circuit breaker cuts off a transformer’s different fault types, there will be different voltage recovery processes. Studying on these transient processes provides bases for the section of breaker and the extraction of fault feature. Based on theoretical analysis and simple calculation, this paper uses PSCAD/EMTDC software to model and emulates every fault system. The results show that when a transformer takes place two-phase grounding fault, the peak of recovery voltage between circuit breaker’s both ends is highest. A conclusion is drawn that when to choose a breaker, pay attention to the two-phase grounding fault.

The present article discusses the clustering analysis used in the near-infrared (NIR) spectroscopy analysis of Chinese traditional medicines, which provides a new method for the classification of Chinese traditional medicines. Samples selected purposely in the authors' research to measure their absorption spectra in seconds by a multi-channel NIR spectrometer developed in the authors' lab were safrole, eucalypt oil, laurel oil, turpentine, clove oil and three samples of costmary oil from different suppliers. The spectra in the range of 0.70-1.7 microm were measured with air as background and the results indicated that they are quite distinct. Qualitative mathematical model was set up and cluster analysis based on the spectra was carried out through different clustering methods for optimization, and came out the cluster correlation coefficient of 0.9742 in the authors' research. This indicated that cluster analysis of the group of samples is practicable. Also it is reasonable to get the result that the calculated classification of 8 samples was quite accorded with their characteristics, especially the three samples of costmary oil were in the closest classification of the clustering analysis.