In this paper, a novel model-dependent scheduling scheme is proposed for the networked control systems with time-delay, disturbance, and medium access constraints. The scheduler calculates the error ...between the ideal dynamic and the real system, and selects the states that make the stability of the system better to access the network. In addition, two kinds of representative time-delays in the networked control systems, constant time-delay and random time-delay, are considered. A robust H-infinity and switched-system-based co-design strategy is introduced to deal with the disturbance in the system, and the system uncertainty introduced by the random time-delay as well. Finally, illustrative examples are given to demonstrate the effectivity of the proposed scheduling method and the co-design scheme.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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•Active learning cycle system was designed to explore high-entropy alloys with exceptional hardness.•Screened 30 Al-Co-Cr-Cu-Fe-Ni compositions exhibit a predicted hardness higher ...than 650 HV.•Four alloys exhibit ultra-high hardness (>740 HV) and low density (<5.9 g/cm3).•Precipitation strengthening of disordered nanoparticles leads to an increase in hardness.
High-entropy alloys (HEAs) have attracted considerable attention for their exceptional microstructures and properties. Discovering new HEAs with desirable properties is crucial, but traditional design methods are laborious and time-consuming. Fortunately, the emerging Machine Learning (ML) offers an efficient solution. In this study, composition-microhardness data pairs from various alloy systems were collected and expanded using a Generative Adversarial Network (GAN). These data pairs were converted into empirical parameter-microhardness pairs. Then Active Learning (AL) was employed to screen the Al-Co-Cr-Cu-Fe-Ni system and identify the eXtreme Gradient Boosting (XGBoost) as the optimal ML master model. Millions of data training iterations employing the XGBoost sub-model and accuracy evaluations using the Expected Improvement (EI) algorithm establish the relationship between HEA compositions and microhardness. The proposed sub-model aligns well with experimental data, wherein four Al-rich compositions exhibit ultra-high microhardness (>740 HV, with a maximum of ∼780.3 HV) and low density (<5.9 g/cm3) in the as-cast bulk state. The hardening increment originates from the precipitation of disordered BCC nanoparticles in the ordered AlCo-rich B2 matrix compared to the dilute B2 AlCo intermetallics. This lightweight, high-performance alloy shows potential for engineering applications as thin films or coatings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nasopharyngeal carcinoma (NPC) is a usual head and neck malignancy. Guggulsterone (GS) has potential in cancer chemoprophylaxis and treatment, but its therapeutic effect on NPC is unknown. We aimed ...to explore whether GS could promote the secretion of exosomal circFIP1L1 from NPC cells and its regulatory mechanism.
NPC tissues and adjacent tissues were collected from NPC patients. Human nasopharyngeal epithelial cell lines (NP69) and NPC lines (5-8F, CNE1, and HNE1) were used for in vitro experiments. HNE1 cells were treated with GS (20, 40, 60 μmol/L). The expressions of miR-125a-5p and circFIP1L1 were evaluated by qRT-PCR. Cell proliferation and apoptosis abilities were measured by CCK-8 and flow cytometry. HNE1 cell exosomes were extracted and identified, and the levels of VEGFA and VEGFR2 were detected by ELISA. Then miR-125a-5p was knocked down and overexpressed. HUVECs angiogenesis was determined by the tube formation assay. qRT-PCR and Western blot were utilized to evaluate the expressions of VEGFA, MMP-2, MMP-9, and ICAM-1 in HUVECs.
miR-125a-5p was highly expressed in NPC tissues and cells. GS promoted the secretion of exosomal circFIP1L1 from HNE1 cells to affect HUVECs proliferation and angiogenesis. Overexpression of miR-125a-5p accelerated HUVECs proliferation and angiogenesis. Knocking down miR-125a- 5p inhibited VEGFA expression. In addition, exosomal circFIP1L1 sponged miR-125a-5p, inhibiting the VEGFA pathway to repress HUVECs angiogenesis.
GS promoted exosomal circFIP1L1 in NPC cells to mediate miR-125a-5p/VEGFA axis affecting tumor angiogenesis.
Network-based control system has been an emerging technology in the control and communication fields in recent years. Modulation is a key step to achieve bandpass transmission, especially for the ...wireless networks. Modulation, an important component in network-based control system, has the detrimental effect on the system performance in some context. In the paper, first, it is shown that the modulation can result in time delay existing not only between sensor and controller, but also between controller and actuator. Then, system stability is analysed, and a robust H ∞ resilient controller restraining controller gain perturbance is designed based on the LMI scheme. Finally, a numerical simulation is used to demonstrate the effectiveness of the designed controller.
Background N6-methyladenosine (m6A) is an important epitranscriptomic mark with high abundance in the brain. Recently, it has been found to be involved in the regulation of memory formation and ...mammalian cortical neurogenesis. However, while it is now established that m6A methylation occurs in a spatially restricted manner, its functions in specific brain regions still await elucidation. Results We identify widespread and dynamic RNA m6A methylation in the developing mouse cerebellum and further uncover distinct features of continuous and temporal-specific m6A methylation across the four postnatal developmental processes. Temporal-specific m6A peaks from P7 to P60 exhibit remarkable changes in their distribution patterns along the mRNA transcripts. We also show spatiotemporal-specific expression of m6A writers METTL3, METTL14, and WTAP and erasers ALKBH5 and FTO in the mouse cerebellum. Ectopic expression of METTL3 mediated by lentivirus infection leads to disorganized structure of both Purkinje and glial cells. In addition, under hypobaric hypoxia exposure, Alkbh5-deletion causes abnormal cell proliferation and differentiation in the cerebellum through disturbing the balance of RNA m6A methylation in different cell fate determination genes. Notably, nuclear export of the hypermethylated RNAs is enhanced in the cerebellum of Alkbh5-deficient mice exposed to hypobaric hypoxia. Conclusions Together, our findings provide strong evidence that RNA m6A methylation is controlled in a precise spatiotemporal manner and participates in the regulation of postnatal development of the mouse cerebellum.
N6-methyladenosine (m6A) is the most abundant epitranscriptomic mark found on mRNA and has important roles in various physiological processes. Despite the relatively high m6A levels in the brain, its ...potential functions in the brain remain largely unexplored. We performed a transcriptome-wide methylation analysis using the mouse brain to depict its region-specific methylation profile. RNA methylation levels in mouse cerebellum are generally higher than those in the cerebral cortex. Heterogeneity of RNA methylation exists across different brain regions and different types of neural cells including the mRNAs to be methylated, their methylation levels and methylation site selection. Common and region-specific methylation have different preferences for methylation site selection and thereby different impacts on their biological functions. In addition, high methylation levels of fragile X mental retardation protein (FMRP) target mRNAs suggest that m6A methylation is likely to be used for selective recognition of target mRNAs by FMRP in the synapse. Overall, we provide a region-specific map of RNA m6A methylation and characterize the distinct features of specific and common methylation in mouse cerebellum and cerebral cortex. Our results imply that RNA m6A methylation is a newly identified element in the region-specific gene regulatory network in the mouse brain.
A novel memory event-triggered scheme for positive systems is proposed in this paper. To address the conservatism of the existing memory event-triggered scheme, the weight parameter on the left side ...of the memory event-triggered scheme is replaced with a dynamic function. This modification results in a dynamic weighted memory event-triggered scheme that can be applied in both continuous-time and discrete-time contexts. By adjusting the weight dynamically based on the system operation, the scheme can respond more effectively to changes in the system state. Compared to the memory event-triggered scheme, a more flexible balance is achieved between improving system performance and saving system resources. A joint design that combines the dynamic weighted memory event-triggered scheme and positive systems is presented for continuous linear systems, with the controller gain obtained by a linear programming strategy. The proposed co-design scheme is subsequently extended to discrete positive systems. To demonstrate the effectiveness of the proposed method, two practical applications are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Network attack detection is a crucial issue in cyber–physical systems. One classical type of network attack is the replay attack. Although the watermarking scheme has proven to be effective in ...detecting replay attacks, it may confront numerous challenges when applied to process control systems. The watermarking signal, which consists of independent and identically distributed Gaussian noise sequences, responds slowly to industrial process control systems. To address this issue, two novel smooth watermarking methods are proposed. The smooth watermarking signals exhibit low-frequency characteristics, enabling them to effectively handle large inertia processes. The proposed schemes are validated through two simulated examples. These examples indicate that the proposed methods can significantly enhance detection efficiency while minimizing additional control performance loss.
The microcrack propagation-coalescence mechanism and stress–strain constitutive model of brittle rock is of great significance for prediction of mechanical properties. To establish a more applicable ...constitutive model of brittle rock, the crack model based on fracture mechanics was introduced. First, based on the crack slip model and maximum circumferential stress theory, a theoretical equation for crack propagation length was established. The microcrack propagation-coalescence mechanism of brittle rock material under loading was studied. On this basis, a macro-coalescence zone model was proposed. Through the relationship between the deformation characteristics of stress–strain curves at different crack growth stages and the behavior of microcracks, a complete stress–strain constitutive model of brittle rock based on the crack model was theoretically deduced. The constitutive model was verified by the results of a coupling hydro-mechanical test of granite carried out after different heat treatment temperatures. The advanced intelligent algorithm, genetic algorithm, was adopted to simulate experimental data. The research results showed that: (1) The derived stress–strain constitutive model of brittle rock is not only high in accuracy of stress–strain simulation, but also can simulate both the axial and circumferential stress–strain curves. Moreover, the dilatancy and crack initiation stresses can be obtained directly. (2) The parameters of the stress–strain constitutive model not only have clear physical meaning, but the mechanisms of rock mechanical properties, such as dilatancy, acoustic emission, and stress fluctuation, can be explained.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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