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This paper is concerned with the problem of pinning synchronization control for a class of nonlinear discrete-time delayed complex cyber-physical networks under all-around attacks. To handle the all-around attacks, a constrained hybrid attacks model is established, which incorporates the pattern feature of false data injection attacks and physical attacks. By utilizing the Lyapunov stability theory and the linear matrix inequality technique, a novel dynamic event-triggering pinning synchronization control scheme is developed to cope with the synchronization control task. Subsequently, sufficient conditions are obtained to guarantee that the closed-loop error dynamics are ultimately exponentially bounded. Furthermore, the design procedure of the synchronization controller is presented for the considered complex cyber-physical networks subject to all-around attacks. Finally, an illustrative example is delivered to demonstrate the effectiveness of the proposed method.

Objective: Cardiac beta2-adrenoceptor (β2AR) has been suggested functions a protective role in defending myocyte apoptosis and cardiac damage induced by various stress. Our recent studies indicate divergent roles of cardiac β2AR in cardiomyocytes and myofibroblasts in regulating high fat diet (HFD) induced cardiac remodeling and dysfunction. While β2AR in cardiomyocytes attenuates HFD-induced cardiac fibrosis, myofibroblast β2AR facilitates cardiac fibrosis. Cell-specific actions of β2AR has been suggested in mediating cardiac fibrosis in the heart. This study is aimed to further determine the role of cardiomyocyte-specific β2AR in cardiac function and cardiac fibrosis. Hypothesis: Cardiomyocyte-specific β2AR regulates cardiac fibrosis via maintaining Ca2+ homeostasis in the heart. Results and Methods: 2-3-month-old mice with cardiomyocyte-specific deletion of β2AR (β2AR-cKO) and β2AR-flox mice were used. While echocardiography showed a comparable cardiac function between cKO and flox mice, the expression of both inflammatory and fibrotic marker proteins, NLR family pyrin domain containing 3 (NLRP3) and connective tissue growth factor (CTGF), was elevated in cKO hearts. As β2AR has been suggested to restrict excessive adrenergic insults, the activities of major molecules in β-adrenergic signaling were examined. Notably, western blot showed the phosphorylation level of Calcium/calmodulin-dependent kinase II (CaMKII) was significantly upregulated in cKO heart which implies a higher level of cytosolic Ca2+. Consequently, the CaMKII phosphorylation site (serine 1700) on L-type Ca2+ channel (LTCC) was also upregulated. To further examine the LTCC activity, whole cell currents (ICa) were recorded from freshly isolated ventricular myocytes, which indicated a higher LTCC activity after isoproterenol stimulation (peak ICa: cKO, -12.87 vs. flox, -10.40, p2+ activity on cardiac inflammatory and fibrotic response. Two weeks of nifedipine injection completely attenuated over-elevated CaMKII activity and NLRP3 and CTGF expression in cKO hearts. Overall, these results indicate that deletion of β2AR in cardiomyocytes facilitates cardiac fibrosis by altering cytosolic Ca2+ homeostasis via LTCC activity. Conclusion: This study elucidates that cardiomyocyte β2AR is essential to maintain normal cardiac function and plays a protective role against the development of cardiac fibrosis. National Institutes of Health grants R01-HL147263, Veteran Affair Merit grant 01BX002900, American Heart Association postdoctoral fellowship This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

In recent years, with the development of smart grid, the power systems and other energy systems are gradually forming integrated energy systems. The electric-thermal integrated energy system is a mature integrated energy system at present. The electric-thermal integrated energy system uses modern communication technology to realize the comprehensive regulation of electric energy and thermal energy, which greatly improves the efficiency of energy use. However, this also greatly increases the risk of malicious tampering with the energy dispatch system. In this paper, we study the regulation of electric-thermal integrated energy systems considering false data injection attacks. First, we establish a compromised model of an electric-thermal integrated energy system considering false data injection attacks. Then, we designed vulnerable variable observers for different tampering scenarios to observe the tampered variables. Finally, considering the relationship between the observed data and the measured data, we design a tampering behavior detection method based on relation network. The simulation results verify the effectiveness of the detection method proposed in this paper.

The influence of organic additives on crystallization of polyolefins has not been paid enough attention due to the low dosage, but it may have a significant impact on the properties of polyolefins. In the paper, the organic amphiphilic molecules were introduced into high-density polyethylene (HDPE) through melt blending, and compared with neat HDPE. It is mainly discussed for the following aspects including analysis of crystal structure and morphology using wide-angle X-ray diffraction (WAXD) and polarized optical microscopy (POM), respectively; analysis of crystallinity, crystal rate, crystal growth and crystallization enthalpy, using the differential scanning calorimetry (DSC). The research indicates that the organic amphiphilic molecules may act as an internal lubricant. On the one hand, HDPE molecular chains are easy to fall off from crystal lattices, resulting in lagging crystallization peak, simultaneously reducing the interaction between HDPE molecules should induce the lower activation energy (ΔEm) to increase the crystallinity of HDPE. On the other hand, the amphiphilic molecules should be exclude from HDPE crystal to the amorphous area due to poor compatibility; thus, the HDPE/amphiphilic molecules blends, similar to neat HDPE, conduct homogeneous nucleation, and the growth of monocrystal performs the tendency of the zero-dimension to the two-dimension with increase in temperature of isothermal crystallization and decreasing cooling rate of non-isothermal crystallization. It is hoped that through these studies, people will pay more attention to the impact of organic additives on the performance of HDPE.

Rationale: β 1 ARs (β 1 -adrenoceptors) exist at intracellular membranes and OCT3 (organic cation transporter 3) mediates norepinephrine entry into cardiomyocytes. However, the functional role of intracellular β 1 AR in cardiac contractility remains to be elucidated. Objective: Test localization and function of intracellular β 1 AR on cardiac contractility. Methods and Results: Membrane fractionation, super-resolution imaging, proximity ligation, coimmunoprecipitation, and single-molecule pull-down demonstrated a pool of β 1 ARs in mouse hearts that were associated with sarco/endoplasmic reticulum Ca 2+ -ATPase at the sarcoplasmic reticulum (SR). Local PKA (protein kinase A) activation was measured using a PKA biosensor targeted at either the plasma membrane (PM) or SR. Compared with wild-type, myocytes lacking OCT3 (OCT3-KO [OCT3 knockout]) responded identically to the membrane-permeant βAR agonist isoproterenol in PKA activation at both PM and SR. The same was true at the PM for membrane-impermeant norepinephrine, but the SR response to norepinephrine was suppressed in OCT3-KO myocytes. This differential effect was recapitulated in phosphorylation of the SR-pump regulator phospholamban. Similarly, OCT3-KO selectively suppressed calcium transients and contraction responses to norepinephrine but not isoproterenol. Furthermore, sotalol, a membrane-impermeant βAR-blocker, suppressed isoproterenol-induced PKA activation at the PM but permitted PKA activation at the SR, phospholamban phosphorylation, and contractility. Moreover, pretreatment with sotalol in OCT3-KO myocytes prevented norepinephrine-induced PKA activation at both PM and the SR and contractility. Conclusions: Functional β 1 ARs exists at the SR and is critical for PKA-mediated phosphorylation of phospholamban and cardiac contractility upon catecholamine stimulation. Activation of these intracellular β 1 ARs requires catecholamine transport via OCT3.

This paper is concerned with the dynamic output feedback control issue for a class of networked control systems with medium access constraints, network-induced delays and packet dropouts. It is assumed that the medium access constraints at both sides of the controller obey the Markov distribution, the upper bound of the network-induced delays is less than one sampling period, and the packet dropouts of networked channels can be described by i.i.d Bernoulli distribution processes. Then, the networked control systems are modelled as a class of asynchronous dynamic systems. According to Lyapunov stability theory and switching system theory, the dynamic output feedback controller is designed to guarantee the exponential stability of networked systems with the given decay rate. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed method.

We have recently identified a pool of intracellular β

SiC–TiB2 ceramic nanocomposites are valuable ultra-high temperature materials, which are rarely prepared from preceramic polymers. In this work, we synthesized SiC–TiB2 nanocomposites from a new preceramic polymer called titanium- and boron-modified polycarbosilane (TB–PCS). The polymer structure was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The structure, composition, and morphology of the resulting ceramic products were investigated by FT-IR, X-ray diffraction, and transmission electron microscopy. The elements of titanium and boron were incorporated into the preceramic polymer, and nanoscale TiB2 and β-SiC grains generated in situ were detected in the pyrolyzed ceramic products at temperatures higher than 1400 °C. The new preceramic polymer presents a novel approach to preparing SiC–TiB2 nanocomposites.

Four mono- and bi-nuclear lanthanide complexes [LnL1(NO3) (H2O)DMF] (Ln = Nd (1) and Yb (2)) and [Ln2 (L2)2(OAc)2] (Ln = Nd (3) and Yb (4)) were synthesized by using two new Schiff base ligands with long (CH2)2NH(CH2)2 backbone. The lengths of the Schiff base ligands are about 1.8 nm. The bi-nuclear lanthanide complexes 3 and 4 have nanoscale structures with sizes of approximately 0.7 nm × 1.1 nm × 1.6 nm. For 3, the molar ratio of Nd:Br:O obtained by the energy dispersive X-ray spectroscopy analysis is in agreement with the crystal structure. The chromogenic Schiff base ligands in 1–4 can efficiently transfer energy to lanthanide ions, thus, these complexes exhibit the typical NIR luminescence of lanthanide ions. Interestingly, 3 and 4 have higher NIR emission quantum yields (Φem) than 1 and 2, respectively.

Bi-based electrode is believed to be one of the promising cathodes for the electroreduction of CO2 to formate. However, it suffers from energy- and/or time-consuming preparation process and mass transfer limitation of the reactants. Here, we fabricated a novel networked Bi-based electrode by formed in situ from Bi dendrites integrated into a Cu mesh substrate via a facile replacement reaction with energy and time savings. The as-prepared electrode was directly used as a cathode for electroreduction of CO2 to formate without further treatment. It exhibits a formate Faraday efficiency of ≈ 100 %. Additionally, partial current density for formate is as high as 68.51 ± 4.04 mA cm-2. This performance outperforms other results obtained on Bi-based electrodes—even most gas-diffusion electrodes under similar conditions. The excellent performance seen here is most likely attributed to its large surface area and fast transport of the reactants. This originates from the Bi dendrites catalysts and the unique network structure of the Cu mesh substrate. This work offers a facile route to obtain an efficient and robust electrode for electroreduction of CO2 to formate, which makes it easy to scale up in industrial applications.

A 1-D coordination polymer [Sm(HL)2(NO3)]n (1) was constructed using a new flexible Schiff base ligand that has a long-chain (CH2)10 backbone. The Schiff base ligand exhibits a linear coordination configuration, resulting in the “zig-zag” structure of 1. Besides the ligand-centered emission, 1 displays typical visible and NIR luminescence of Sm3+. Interestingly, 1 shows dual-emissive response to metal ions, especially to Co2+ at the ppm level.

We have recently identified a pool of intracellular β1 adrenergic receptors (β1ARs) at the sarcoplasmic reticulum (SR) crucial for cardiac function. Here, we aim to characterize the integrative control of intracellular catecholamine for subcellular β1AR signaling and cardiac function. Using anchored Förster resonance energy transfer (FRET) biosensors and transgenic mice, we determined the regulation of compartmentalized β1AR-PKA signaling at the SR and plasma membrane (PM) microdomains by organic cation transporter 3 (OCT3) and monoamine oxidase A (MAO-A), two critical modulators of catecholamine uptake and homeostasis. Additionally, we examined local PKA substrate phosphorylation and excitation–contraction coupling in cardiomyocyte. Cardiac-specific deletion of MAO-A (MAO-A-CKO) elevates catecholamines and cAMP levels in the myocardium, baseline cardiac function, and adrenergic responses. Both MAO-A deletion and inhibitor (MAOi) selectively enhance the local β1AR-PKA activity at the SR but not PM, and augment phosphorylation of phospholamban, Ca2+ cycling, and myocyte contractile response. Overexpression of MAO-A suppresses the SR-β1AR-PKA activity and PKA phosphorylation. However, deletion or inhibition of OCT3 by corticosterone prevents the effects induced by MAOi and MAO-A deletion in cardiomyocytes. Deletion or inhibition of OCT3 also negates the effects of MAOi and MAO-A deficiency in cardiac function and adrenergic responses in vivo. Our data show that MAO-A and OCT3 act in concert to fine-tune the intracellular SR-β1AR-PKA signaling and cardiac fight-or-flight response. We reveal a drug contraindication between anti-inflammatory corticosterone and anti-depressant MAOi in modulating adrenergic regulation in the heart, providing novel perspectives of these drugs with cardiac implications.

The power system is evolving from a single energy system to an integrated energy system. In order to further improve the power generation and consumption balance capacity of the park integrated energy system (PIES), the park integrated energy system is gradually transitioning from the single park energy system operation mode to the multipark energy system operation mode. The design of multipark integrated energy system (MPIES) collaborative control strategy will become an important part to improve the power generation and consumption balance ability of the integrated energy system. In order to fully tap the regulation capacity of each PIES, we propose a coordinated control strategy for the integrated energy system in multiple parks considering the flexible substitution interval of multiple types of energy. Firstly, we analyze the influence of the types of regulation resources and the regulation incentive mechanism of the PIES on the regulation flexible range of the PIES. Then, based on the Markov decision process, a distributed cluster regulation model of MPIES considering regulation demand and regulation flexible interval is established. Finally, using multilayer deep Q networks (MLDQN), the distributed cluster regulation optimization algorithm of MPIES is given. The simulation results show that the proposed method can coordinate the regulation ability of each park integrated energy system in the MPIES, give full play to the large-scale advantage of the interconnection of the park integrated energy system, and improve the overall stability of the multipark integrated energy system.

RNA binding motif 20 (RBM20) cardiomyopathy has been detected in approximately 3% of populations afflicted with dilated cardiomyopathy (DCM). It is well conceived that RBM20 cardiomyopathy is provoked by titin isoform switching in combination with resting Ca2+ leaking. In this study, we characterized the cardiac function in Rbm20 knockout (KO) rats at 3‐, 6‐, 9‐, and 12‐months of age and examined the effect of the ryanodine receptor stabilizer S107 on resting intracellular levels and cardiomyocyte contractile properties. Our results revealed that even though Rbm20 depletion promoted expression of larger titin isoform and reduced myocardial stiffness in young rats (3 months of age), the established DCM phenotype required more time to embellish. S107 restored elevated intracellular Ca2+ to normal levels and ameliorated cardiomyocyte contractile properties in isolated cardiomyocytes from 6‐month‐old Rbm20 KO rats. However, S107 failed to preserve cardiac homeostasis in Rbm20 KO rats at 12 months of age, unexpectedly, likely due to the existence of multiple pathogenic mechanisms. Taken together, our data suggest the therapeutic promises of S107 in the management of RBM20 cardiomyopathy., Loss of Rbm20 results in reduced myocardial stiffness at younger age and overt RBM20 cardiomyopathy at older age in rats. The RyR2 stabilizer S107 improves contractility properties by restoring the elevated resting intracellular Ca2+ level in Rbm20‐depleted cardiomyocytes. S107 could be a component of a therapeutic option for RBM20 cardiomyopathy.

In the construction of a photovoltaic power station, the effect of ray tracing directly affects the efficiency of power generation. In order to effectively control the tracking photovoltaic bracket and present the actual situation of the tracking bracket truly, intuitively and conveniently, a roamable photovoltaic tracking bracket control system is designed in this study. The system provides assistant decision-making for operators, and can remotely control the tracking support in real-time. It can also work independently according to the set parameters to realize the functions of the sun position calculation, tracking angle calculation, and tracking command output, and can communicate with the monitoring terminal. During the experimental test, the computer resource occupation is low, the operation is stable and reliable, and the monitoring terminal can run with a relatively smooth frame number. According to the system architecture mentioned in this paper, the verification platform is built, and the effectiveness of the photovoltaic tracking bracket control system is confirmed. The control system of the photovoltaic tracking bracket designed in this paper can effectively solve the problem of solar tracking accuracy of the photovoltaic power station, and play an important role in improving the power generation efficiency of the photovoltaic power station. At the same time, it can provide a reference for the same industry in light source tracking technology.

A coupled electrochemical system (CES) for the electroreduction of CO2 to formate (ERCF) and simultaneous degradation of organic pollutants is a promising approach for CO2 conversion. Cathode material is a critical component of CES. However, the poor performance and complexity of synthesis limit its real application. Here, we report a Bi-based binder-free gas diffusion electrode (EBGDE) as a high-performance cathode for CES. The EBGDE was fabricated via direct electrodeposition of Bi nanosheets on a gas diffusion layer. By optimizing the deposition time of Bi nanosheets, a good Faraday efficiency (91.46 ± 6.58%) and formate production rate (1849.96 ± 127.69 μmol m−2 s−1) were obtained. Simultaneously, the methyl orange decolorization efficiency and chemical oxygen demand removal efficiency reached 100% and 55.25 ± 6.87%, respectively. This performance towards ERCF is better than recently reported ERCF electrodes. It probably results from the excellent performance of associated Bi-nanosheets catalysts, a high electroactive surface area, as well as fast electron transfer in the EBGDE. This work offers design rules to fabricate high-performance cathode materials for CES in industrial applications.

Two tetranuclear Ni–Ln nanoclusters [Ni2Ln2(L)2(OAc)6] (Ln = Eu (1) and Yb (2)) were synthesized by the using of a new Schiff base ligand with Ph-S-Ph backbone. The sulfur atom of the Schiff base ligand is coordinated with the Ni2+ ion. 1 and 2 have planar structures and their molecular sizes are about 6 × 11 × 19 A. Upon the excitation of ligand-centered absorption, 2 exhibits the typical NIR luminescence of Yb3+. The lanthanide luminescence lifetime (τ) and quantum yield (Φem) of 2 in CH3CN are 5.18 μs and 0.04%, respectively.

In this paper, we discuss the modeling and control problem for networked systems with access constraints and packet dropouts. Due to the limitation of communication capacity, only the limited number of sensors and actuators are allowed to gain access to network medium according to a stochastic access protocol, and packet dropouts may happen in both backward and forward channels, which can be described by i.i.d Bernoulli processes. Under consideration of the access constraints and packet dropouts, the networked control system can be modelled as a Markov jump system. In such a framework, to solve the controller synthesis problem, the time-varying Kalman filter is first designed. Then, by using the theory of Markovian jump systems and dynamic programming, an optimal controller is designed such that the networked system is exponentially mean-square stable while minimizing the quadratic cost. Finally, two illustrative examples are given to demonstrate the effectiveness of the proposed results.

Five new cadmium(II) coordination polymers [Cd(HPBO)(2,2′-bipy)]n (C1), (H3PBO = 4,4′-(hydroxyphosphoryl)dibenzoic acid, 2,2′-bipy = 2,2′-bipyridine), [Cd(HPBO)(phen)]n (C2), (phen = 1,10-phenanthroline), [Cd(HPBO)(4,4′-bipy)0.5]n (C3) (4,4′-bipy = 4,4′-bipyridine), [Cd(HPBO)(dpe)0.5]n (C4), (dpe = 1,2-di(pyridin-4-yl)ethene), [Cd2(HPBO)2(dpp)]n (C5), (dpp = 1,3-di(pyridin-4-yl)propane) were synthesized and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. The thermal stabilities and luminescence properties of compounds C1–C5 were investigated. The N-donor ligands influence the coordination mods of the Cd(II) centers and dimensionality of the structures and H3PBO accept either bridging and chelating modes. C2 exhibits a 3-connected 2D network of a hcb topology with a point symbol of (63). C3 and C4 show the same unprecedented (4, 10)-connected 3D network with a point symbol of (412·511·618·73·8)(46)2. C5 presents a (4, 10)-connected 3D network of a deh1 topology with a point symbol of (3·45)2(34·412·510·614·73·82).

Background: Epithelial-to-mesenchymal transition (EMT) is a process whereby epithelial cells lose cell-cell contacts and acquire expression of mesenchymal components and manifest a migratory phenotype. Recent studies indicated that EMT is involved in the development of keloids. Therefore, this study aims to investigate the mechanisms of the effects of metformin in hypoxia-induced EMT in keloid fibroblasts (KFs). Methods: KFs were cultured in a hypoxia incubator to induce EMT and were treated with or without metformin. Cell viability was evaluated by a cell counting kit 8 (CCK-8), and cell migration was measured by the transwell assay. The expression levels of HIF-1α, E-cadherin, vimentin, phosphorylated p70s6k (p-p70s6k) and pyruvate kinase M2 (PKM2) were evaluated by western blotting. Results: Hypoxia promoted EMT in KFs. Metformin significantly inhibited the expression of HIF-1α and partially abolished hypoxia-induced EMT. PKM2 is involved in hypoxia-induced EMT of KFs and metformin decreased the expression of p-p70s6k and PKM2. Conclusions: Metformin abolishes hypoxia-induced EMT in KFs by inhibiting the HIF-1α/PKM2 signaling pathway. Our study provides a novel mechanistic insight into potential use of metformin for treatment of keloids.