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In this paper, we study the stability of solutions of stochastic McKean-Vlasov equations via feedback control based on discrete-time state observation. By using a specific Lyapunov function, the H∞ stability, asymptotic stability and exponential stability in mean square for the solution of the controlled systems are obtained. Since the distribution of the solution is difficult to observe, we study the corresponding particle system which can be observed for the feedback control. We prove that the exponential stability of control system is equivalent to the the exponential stability of the corresponding particle system. Finally, an example is provided to show the effectiveness of the theory. [ABSTRACT FROM AUTHOR]

A novel approach for designing the feedback control based on past states is proposed for hybrid stochastic differential equations (SDEs). This new theorem builds up the connection between the delay feedback control and the control function without delay terms, which enables one to construct the delay feedback control using the existing results on stabilities of hybrid SDEs. Methods for finding the upper bound of the length of the time delay are also investigated. Numerical simulations are presented to demonstrate the new theorem. [ABSTRACT FROM AUTHOR]

The limited availability of experimental tumor models that faithfully mimic the progression of human tumors and their response to therapy remains a major bottleneck to the clinical translation and application of novel therapeutic principles. To address this challenge in hepatocellular carcinoma (HCC), one of the deadliest and most common cancers in the world, we developed and validated an inducible model of hepatocarcinogenesis in adult mice. Tumorigenesis was triggered by intravenous adenoviral delivery of Cre recombinase in transgenic mice expressing the hepatocyte-specific albumin promoter, a loxP-flanked stop cassette, and the SV40 large Tantigen (iAST). Cre recombinase--mediated excision of the stop cassette led to a transient viral hepatitis and resulted in multinodular tumorigenesis within 5 to 8 weeks. Tumor nodules with histologic characteristics of human HCC established a functional vasculature by cooption, remodeling, and angiogenic expansion of the preexisting sinusoidal liver vasculature with increasing signs of vascular immaturity during tumor progression. Treatment of mice with sorafenib rapidly resulted in the induction of vascular regression, inhibition of tumor growth, and enhanced overall survival. Vascular regression was characterized by loss of endothelial cells leaving behind avascular type IV collagen--positive empty sleeves with remaining pericytes. Sorafenib treatment led to transcriptional changes of Igf1, Id1, and cMet over time, which may reflect the emergence of potential escape mechanisms. Taken together, our results established the iAST model of inducible hepatocarcinogenesis as a robust and versatile preclinical model to study HCC progression and validate novel therapies. [ABSTRACT FROM AUTHOR]

Liver regeneration requires spatially and temporally precisely coordinated proliferation of the two major hepatic cell populations, hepatocytes and liver sinusoidal endothelial cells (LSECs), to reconstitute liver structure and function. The underlying mechanisms of this complex molecular cross-talk remain elusive. Here, we show that the expression of Angiopoietin-2 (Ang2) in LSECs is dynamically regulated after partial hepatectomy. During the early inductive phase of liver regeneration, Ang2 down-regulation leads to reduced LSEC transforming growth factor-β1 production, enabling hepatocyte proliferation by releasing an angiocrine proliferative brake. During the later angiogenic phase of liver regeneration, recovery of endothelial Ang2 expression enables regenerative angiogenesis by controlling LSEC vascular endothelial growth factor receptor 2 expression. The data establish LSECs as a dynamic rheostat of liver regeneration, spatiotemporally orchestrating hepatocyte and LSEC proliferation through angiocrine- and autocrine-acting Ang2, respectively. [ABSTRACT FROM AUTHOR]

We consider a class of stochastic delay recurrent neural networks with distributed parameters and Markovian jumping. It is assumed that the coefficients in these neural networks belong to the interval matrices. Several sufficient conditions ensuring robust exponential stabilization are derived by using periodically intermittent control and Lyapunov functional. The obtained results are very easy to verify and implement, and improve the existing results. Finally, an example with numerical simulations is given to illustrate the presented criteria. [ABSTRACT FROM AUTHOR]

We develop exponential stability of neutral stochastic functional differential equations with two-time-scale Markovian switching modeled by a continuous-time Markov chain which has a large state space. To overcome the computational effort and the complexity, we split the large-scale system into several classes and lump the states in each class into one class by the different states of changes of the subsystems; then, we give a limit system to effectively "replace" the large-scale system. Under suitable conditions, using the stability of the limit systemas a bridge, the desired asymptotic properties of the large-scale system with Brownian motion and Poisson jump are obtained by utilizing perturbed Lyapunov function methods and Razumikhin-type criteria. Two examples are provided to demonstrate our results. [ABSTRACT FROM AUTHOR]

This paper concerns Razumikhin-type theorems on exponential stability of stochastic differential delay equations withMarkovian switching, where the modulating Markov chain involves small parameters. The smaller the parameter is, the rapider switching the system will experience. In order to reduce the complexity, we will "replace" the original systems by limit systems with a simple structure. Under Razumikhin-type conditions, we establish theorems that if the limit systems are pth-moment exponentially stable; then, the original systems are pth-moment exponentially stable in an appropriate sense. [ABSTRACT FROM AUTHOR]

We investigate the convergence rate of Euler-Maruyamamethod for a class of stochastic partial differential delay equations driven by both Brownian motion and Poisson point processes. We discretize in space by a Galerkin method and in time by using a stochastic exponential integrator. We generalize some results of Bao et al. (2011) and Jacob et al. (2009) in finite dimensions to a class of stochastic partial differential delay equations with jumps in infinite dimensions. [ABSTRACT FROM AUTHOR]

In view of the common problems of integrating artificial intelligence into the training of postgraduates in Acupuncture and Tuina major, this paper reviews the related research progress both at home and abroad. It puts forward the innovative reform paths for integrating artificial intelligence into postgraduate training mode of Acupuncture and Tuina major; construct the teaching staff of artificial intelligence graduate students; innovating artificial intelligence to promote the integration of classics and scientific research; constructing the ideological and political case base of artificial intelligence courses; implementing artificial intelligence platform blended teaching; building a domestic and foreign exchange platform for artificial intelligence. Through practical research in teaching, it has achieved good teaching results and played a good demonstration, leading and radiation role in similar majors in China. [ABSTRACT FROM AUTHOR]

Endothelial cells (ECs) not only are important for oxygen delivery but also act as a paracrine source for signals that determine the balance between tissue regeneration and fibrosis. Here we show that genetic inactivation of flow-induced transcription factor Krüppel-like factor 2 (KLF2) in ECs results in reduced liver damage and augmentation of hepatocyte proliferation after chronic liver injury by treatment with carbon tetrachloride (CCl4). Serum levels of GLDH3 and ALT were significantly reduced in CCl4-treated ECspecific KLF2-deficient mice. In contrast, transgenic overexpression of KLF2 in liver sinusoidal ECs reduced hepatocyte proliferation. KLF2 induced activin A expression and secretion from endothelial cells in vitro and in vivo, which inhibited hepatocyte proliferation. However, loss or gain of KLF2 expression did not change capillary density and liver fibrosis, but significantly affected hepatocyte proliferation. Taken together, the data demonstrate that KLF2 induces an antiproliferative secretome, including activin A, which attenuates liver regeneration. [ABSTRACT FROM AUTHOR]

To investigate the correlation between the physicochemical and hygroscopic properties of biochar and soil, the moisture sorption properties of typical biochars and soils were observed inside a thermostatically controlled incubator at a temperature of 30 °C and humidity of 70%. Results showed that the equilibrium moisture content (EMC) of tobacco stem biochar, rice husk biochar, Hubei paddy soil, and Jiangxi red soil were 7.66%, 6.40%, 3.34%, and 2.92%, respectively. There was a synergistic interaction between biochar and soil, resulting in a higher EMC of biochar-soil mixtures with increases ranging from 0.16% to 2.52%. The porosity of tobacco stem biochar, rice husk biochar, Hubei paddy soil, and Jiangxi red soil were 82.58%, 65.05%, 59.02%, and 56.71%, respectively. Additionally, according to our findings, the biochar had higher carbon content, C/N ratio, and carbonyl groups, and lower bulk density, oxygen content, O/C ratio, and carboxyl groups than the soil. The linear correlation analysis indicated that there was a positive correlation between EMC and the physicochemical properties of biochar and soil, including porosity, carbon content, nitrogen content, and carboxyl groups. Consideration of the physicochemical properties of biochar and soil will significantly improve the overall properties of biochar used for soil amendment. [ABSTRACT FROM AUTHOR]

Multiple cell types involved in the regulation of angiogenesis express Wnt ligands. Although β-catenin dependent and independent Wnt signaling pathways have been shown to control angiogenesis, the contribution of individual cell types to activate these downstream pathways in endothelial cells (ECs) during blood vessel formation is still elusive. To investigate the role of ECs in contributing Wnt ligands for regulation of blood vessel formation, we conditionally deleted the Wnt secretion factor Evi inmouseECs (Evi-ECKO).Evi-ECKO mice showed decreased microvessel density during physiological and pathological angiogenesis in the postnatal retina and in tumors, respectively. The reduced microvessel density resulted from increased vessel regression accompanied by decreased EC survival and proliferation. Concomitantly, survival-related genes were downregulated and cell cycle arrest- and apoptosis-inducing genes were upregulated. EVI silencing in cultured HUVECs showed similar target gene regulation, supporting a mechanism of EC-derived Wnt ligands in controlling EC function. ECs preferentially expressed non-canonical Wnt ligands and canonical target gene expression was unaffected in Evi-ECKO mice. Furthermore, the reduced vascularization ofMatrigel plugs in Evi-ECKO mice could be rescued by introduction of non-canonical Wnt5a. Treatment of mouse pups with the non-canonical Wnt inhibitor TNP470 resulted in increased vessel regression accompanied by decreased EC proliferation, thus mimicking the proliferation-dependent Evi-ECKO remodeling phenotype. Taken together, this study identified EC-derived non-canonical Wnt ligands as regulators of EC survival, proliferation and subsequent vascular pruning during developmental and pathological angiogenesis. [ABSTRACT FROM AUTHOR]

In recent years, air pollution control has caused great concern. This paper focuses on the primary pollutant SO2 in the atmosphere for analysis and control. Two indicators are introduced, which are the concentration of SO2 in the emissions (PSO2) and the concentration of SO2 in the atmosphere (ASO2). If the ASO2 is higher than the certain threshold, then this shows that the air is polluted. According to the uncertainty of the air pollution control systems model, H∞ control theory for the air pollution control systems is used in this paper, which can change the PSO2 with the method of improving the level of pollution processing or decreasing the emissions, so that air pollution system can maintain robust stability and the indicators ASO2 are always operated within the desired target. [ABSTRACT FROM AUTHOR]

Tunable assembly of cellulose nanocrystals (CNCs) is important for a variety of emerging applications in optics, sensing, and security. Most exploited assembly and optical property of CNCs are cholesteric assembly and corresponding circular dichroism. However, it still remains challenge to obtain homogenous and high-resolution cholesteric assembly. Distinct assembly and optical property of CNCs are highly demanded for advanced photonic materials with novel functions. Herein, a facile and programmable approach for assembling CNCs into a novel concentric alignment using capillary flow and Marangoni effect, which is in strike contrast to conventional cholesteric assembly, is demonstrated. The concentric assembly, as quantitatively evidenced by polarized synchrotron radiation Fourier transform infrared imaging, demonstrates Maltese cross optical pattern with good uniformity and high resolution. Furthermore, this Maltese cross can be readily regulated to “on/off” states by temperature. By combining with 3D inkjet technology, a functional binary system composed of “on”/“off” CNCs optical patterns with high spatial resolution, fast printing speed, good repeatability, and precisely controllable optical property is established for information encryption and decryption. This concentric assembly of CNCs and corresponding tunable optical property emerge as a promising candidate for information security, anticounterfeiting technology, and advanced optics. [ABSTRACT FROM AUTHOR]

Transforming growth factor β-activated kinase1 (TAK1) encoded by the gene MAP3K7 regulates multiple important downstream effectors involved in immune response, cell death, and carcinogenesis. Hepatocyte-specific deletion of TAK1 in Tak1ΔHEP mice promotes liver fibrosis and hepatocellular carcinoma (HCC) formation. Here, we report that genetic inactivation of RIPK1 kinase using a kinase dead knockin D138N mutation in TakΔHEP mice inhibits the expression of liver tumor biomarkers, liver fibrosis, and HCC formation. Inhibition of RIPK1, however, has no or minimum effect on hepatocyte loss and compensatory proliferation, which are the recognized factors important for liver fibrosis and HCC development. Using single-cell RNA sequencing, we discovered that inhibition of RIPK1 strongly suppresses inflammation induced by hepatocyte-specific loss of TAK1. Activation of RIPK1 promotes the transcription of key proinflammatory cytokines, such as CCL2, and CCR2+ macrophage infiltration. Our study demonstrates the role and mechanism of RIPK1 kinase in promoting inflammation, both cell-autonomously and cell-nonautonomously, in the development of liver fibrosis and HCC, independent of cell death, and compensatory proliferation. We suggest the possibility of inhibiting RIPK1 kinase as a therapeutic strategy for reducing liver fibrosis and HCC development by inhibiting inflammation. [ABSTRACT FROM AUTHOR]

Septic shock is characterized by increased vascular permeability and hypotension despite increased cardiac output. Numerous vasoactive cytokines are upregulated during sepsis, including angiopoietin 2 (ANG2), which increases vascular permeability. Here we report that mice engineered to inducibly overexpress ANG2 in the endothelium developed sepsis-like hemodynamic alterations, including systemic hypotension, increased cardiac output, and dilatory cardiomyopathy. Conversely, mice with cardiomyocyte-restricted ANG2 overexpression failed to develop hemodynamic alterations. Interestingly, the hemodynamic alterations associated with endothelial-specific overexpression of ANG2 and the loss of capillary-associated pericytes were reversed by intravenous injections of adeno-associated viruses (AAVs) transducing cDNA for angiopoietin 1, a TIE2 ligand that antagonizes ANG2, or AAVs encoding PDGFB, a chemoattractant for pericytes. To confirm the role of ANG2 in sepsis, we i.p. injected LPS into C57BL/6J mice, which rapidly developed hypotension, acute pericyte loss, and increased vascular permeability. Importantly, ANG2 antibody treatment attenuated LPS-induced hemodynamic alterations and reduced the mortality rate at 36 hours from 95% to 61%. These data indicate that ANG2-mediated microvascular disintegration contributes to septic shock and that inhibition of the ANG2/TIE2 interaction during sepsis is a potential therapeutic target. [ABSTRACT FROM AUTHOR]

This paper introduces a new series of three-dimensional chaotic systems with cross-product nonlinearities. Based on some conditions, we analyze the globally exponentially or globally conditional exponentially attractive set and positive invariant set of these chaotic systems. Moreover, we give some known examples to show our results, and the exponential estimation is explicitly derived. Finally, we construct some three-dimensional chaotic systems with cross-product nonlinearities and study the switching system between them. [ABSTRACT FROM AUTHOR]

The sufficient conditions of existence and uniqueness of the solutions for nonlinear stochastic pantograph equationswith Markovian switching and jumps are given. It is proved that Euler-Maruyama scheme for nonlinear stochastic pantograph equations with Markovian switching and Brownian motion is of convergence with strong order 1/2. For nonlinear stochastic pantograph equations with Markovian switching and pure jumps, it is best to use the mean-square convergence, and the order of mean-square convergence is close to 1/2. [ABSTRACT FROM AUTHOR]

The mechanisms of blood vessel maturation into distinct parts of the blood vasculature such as arteries, veins, and capillaries have been the subject of intense investigation over recent years. In contrast, our knowledge of lymphatic vessel maturation is still fragmentary. In this study, we provide a molecular and morphological characterization of the major steps in the maturation of the primary lymphatic capillary plexus into collecting lymphatic vessels during development and show that forkhead transcription factor Foxc2 controls this process. We further identify transcription factor NFATc1 as a novel regulator of lymphatic development and describe a previously unsuspected link between NFATc1 and Foxc2 in the regulation of lymphatic maturation. We also provide a genome-wide map of FOXC2-binding sites in lymphatic endothelial cells, identify a novel consensus FOXC2 sequence, and show that NFATc1 physically interacts with FOXC2-binding enhancers. As damage to collecting vessels is a major cause of lymphatic dysfunction in humans, our results suggest that FOXC2 and NFATc1 are potential targets for therapeutic intervention. [ABSTRACT FROM AUTHOR]