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In the present study, a hydraulic shock absorber is proposed. Since the damper is mainly used in suspension energy recovery system, the damping characteristics of the damper under no-load state are studied in this paper. Structural design is conducted so that the unidirectional flow of the oil drives the hydraulic motor to generate electricity. Meanwhile, an asymmetrical extension/compression damping force is obtained. A mathematical model of the shock absorber is established, and the main characteristics of the inherent damping force are obtained. Based on the established model, effects of the accumulator volume, accumulator preinflation pressure, hydraulic motor displacement, check valve inner diameter, and spring stiffness, hydraulic line length and inner diameter on the indicator characteristics are analyzed. Moreover, a series of experiments are conducted on the designed damper to evaluate the characteristics of the inherent damping force and analyze the effect of the accumulator volume and preinflation pressure on the damping characteristics. [ABSTRACT FROM AUTHOR]

This paper proposes a hydraulic energy-harvesting shock absorber prototype, which realizes energy harvesting of the vibration energy dissipated by the automobile suspension system. The structural design of the proposed shock absorber ensures that the unidirectional flow of oil drives the hydraulic motor to generate electricity while obtaining an asymmetrical extension/compression damping force. A mathematical model of the energy-harvesting shock absorber is established, and the simulation results indicate that the damping force can be controlled by varying the load resistance of the feed module, thus adjusting the required damping force ratio of the compression and recovery strokes. By adjusting the external load, the target indicator performance of the shock absorber is achieved while obtaining the required energy recovery power. A series of experiments are conducted on the prototype to verify the validity of the damping characteristics and the energy recovery efficiency as well as to analyze the effect of external load and excitation speed on these characteristics. [ABSTRACT FROM AUTHOR]

Presents a theoretical investigation on the quantum field effect directional coupler. General formulation of the device; Calculation of the transfer length; Conductance of the device.

Discusses a study that proposed a mode selector to realize single modedness in the waveguidelike quantum devices. Application of a mode selector to quantum devices; Demonstration of the mode selecting function by the principle of resonant tunneling effect; Description of the mode selector on a typical electron waveguide.

Inhibition of SIRT3 exhibited potency in triggering leukemic cell differentiation. In discovery of potent SIRT3 inhibitors for cancer differentiation therapy, structural modification was performed on the previously developed lead compound P6. A total of 33 compounds were designed and synthesized. In the enzyme inhibitory assay, several molecules S18, S26, S27 and T5 showed potent SIRT3 inhibitory activity with IC50 value of 0.53, 1.86, 5.06, and 2.88 μM, respectively. Moreover, the tested compounds exhibited SIRT3 inhibitory selectivity over SIRT1 and SIRT2. Compounds S27 and T5 were potent in inhibition the growth of MM1.S and RPMI‐8226 cells in the in vitro antiproliferative test. Significantly, representative compounds, especially S27 and T5, promoted differentiation of tested MM cells in the cellular morphological evaluation, accompanied by increasing the expression of differentiation antigen CD49e and human immunoglobulin light chain lambda and kappa. Additionally, molecule S18 without antiproliferative potency itself, showed significant inhibitory activity against growth factor IL‐6 induced RPMI‐8226 cell proliferation. Collectively, potent SIRT3 selective inhibitors with MM cell differentiation potency were developed for further discovery of anticancer drugs. [ABSTRACT FROM AUTHOR]

A series of novel 4-Hydroxyquinazoline derivatives were designed and synthesized to enhance sensitivity in primary PARPi-resistant cells. Among them, the compound B1 has been found to have superior cytotoxicity in primary PARPi-resistant HCT-15 and HCC1937 cell lines, and dose-dependently suppressed the intracellular PAR formation and enhanced the γH2AX aggregation. Mechanistic study showed that B1 stimulated the formation of intracellular ROS and the depolarization of the mitochondrial membrane, which could increase apoptosis and cytotoxicity. An in vivo study showed that B1 significantly suppressed tumor growth at a dose of 25 mg/kg, and an acute toxicity study confirmed its safety. Molecular docking and dynamics simulations revealed that hydrogen bonding between B1 and ASP766 may be helpful to enhance anti-drug resistance ability. This study suggests that B1 is a potent PARP inhibitor that can overcome PARPi resistance and deserves further investigation. [ABSTRACT FROM AUTHOR]

Commercially available normally-off GaN power high-electron-mobility transistor (HEMT) devices have typically adopted a p-GaN gate structure. In the gate region, there exist a Schottky junction (between gate electrode and the p-GaN layer) and a p-GaN/AlGaN/GaN heterojunction. As the p-GaN layer is not directly shorted to the gate electrode and conducting channel, it can be considered as electrically “floating.” With drain voltage changing during a switching process, the variation of net charge in the floating p-GaN layer would cause instability in threshold voltage. Besides, because of the distinctive features of the p-GaN gate HEMT structure under certain gate/drain bias, gate-related junction capacitances would exhibit behavior different from those of a Si mosfet. Consequently, the switching transient performance of a GaN transistor with a p-GaN gate could be significantly influenced by the aforementioned factors. In this work, the threshold voltage instability associated with the drain-to-gate voltage stress is first analyzed. Despite the difficulty in directly performing capacitance measurements inside the device structure, a hybrid physical-behavior modeling method is proposed. The model is capable of extracting the capacitance bias relationships with regard to the gate region from static terminal measurements. In previous works, the advanced analytical model would make modest change on a Si mosfet's model. As a result, without fully considering the specific features of a GaN transistor with the p-GaN gate, the simulated waveforms would exhibit 20–50% discrepancy from the experiment. In contrast, the proposed switching transient analytical approach would exhibit improved accuracy (<10% disparity). Consequently, the switching transient performance of the GaN transistor with the p-GaN gate could be more accurately evaluated. [ABSTRACT FROM AUTHOR]

This paper addresses the consensus control problem for a class of multi-agent systems with distributed parameter models, and all the agents in the considered systems are governed by the one-dimensional parabolic equations or the one-dimensional second-order hyperbolic equations. The main contribution of this paper is to apply Lyapunov functional approach to the multi-agent systems with distributed parameter models, and solve the consensus control problem of such multi-agent systems on an appropriate Sobolev space. The distributed consensus-based feedback control protocols are obtained based on the virtual leader approach, and when the feedback control laws are applied to the systems, consensus on L 2 (0, 1) space (corresponding to the parabolic equations) or on W 1, 2 (0, 1) ×  L 2 (0, 1) space (corresponding to the hyperbolic equations) is achieved for all the directed communication graphs with spanning trees. Simulation examples illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A novel strategy for designing stable and efficient photosensitizers, aimed at promoting ROS generation for efficient tumor immunotherapy, is reported first. The introduced electron-withdrawing group optimize the stability and ΔE ST of PCy5-2Cl for boosting ROS production. Due to the endoplasmic reticulum (ER) targeted ability and efficient ROS generation of PCy5-2Cl NPs, the intense ER stress arouses immunogenic cell death to realize tumor immune therapy. This work establishes a pioneering pathway for designing photodynamic immunotherapy drugs. [Display omitted] • An antioxidative endoplasmic reticulum-targeted photosensitive drug is designed for efficient tumor immunotherapy. • The electron-withdrawing groups are introduced in the meso -position to modulate the electron structure of PCy5 photosensitizers. • Optimized electron structure affords PCy5-2Cl enhanced antioxidative ability and small ΔE ST for efficient ROS production. • The combination of endoplasmic reticulum-targeted ability and abundant ROS trigger the immunogenic cell death for bilateral tumor immunotherapy. • The electron-withdrawing strategy and corresponding mechanisms provide a new insight for exploring efficient photodynamic immunotherapy drugs. Excessive generation of reactive oxygen species (ROS) triggers intense endoplasmic reticulum (ER) stress, emerging as a key mechanism for arousing autoimmune therapy. Therefore, the development of an ER-targeted ROS generator is crucial for advancing self-immunotherapy. However, despite a clear demand for ER-targeting ROS generators, the high-efficiency agents are still limited. In this study, the pentamethine cyanine dye (Cy5) is used as a parent structure to explore the efficient ER-targeted immune activator. Three variants (PCy5-H, PCy5-Cl, and PCy5-2Cl) were synthesized by introducing benzene, chlorobenzene, and dichlorobenzene structures at the meso -position of the Cy5 scaffold. The electron-withdrawing groups (EWGs) effectively reduce the electron density on the conjugate chain, facilitating the intersystem crossing (ISC) process and enhancing the antioxidant capability. Consequently, the antioxidant properties and ROS generation capacity of PCy5-2Cl were enhanced. Furthermore, encapsulating PCy5-2Cl into liposomes significantly improves its retention at the tumor site, inducing robust ER stress. Upon accumulation at the ER sites in tumor cells, PCy5-2Cl nanoparticles induced strong ER stress under near-infrared (NIR) light irradiation. Exposure to necrotic fragments reverses the immunosuppressive microenvironment within the tumor, ultimately promoting dendritic cell maturation and infiltration of cytotoxic T lymphocytes (CTLs). As a result, significant inhibition is observed in both primary and distant tumors, underscoring the efficacy of this EWGs modification strategy for enhancing tumor immunotherapy. [ABSTRACT FROM AUTHOR]

A dual-targeted strategy for co-triggering the apoptosis and immunogenic death in TCy5 photosensitizer was first proposed. The introduced tri-fluorophenyl group and halogen atoms afford the materials excellent mitochondria and endoplasmic reticulum targeting ability. Further, the optimized excited state and electron density boost ROS production in the treatment process. This work paves a new way for rationally designing efficient photosensitive drugs for cancer treatment. [Display omitted] • A dual-targeted TCy5-based photosensitive drug is designed for effective cancer treatment. • The obtained drugs show excellent mitochondria and endoplasmic reticulum targeting ability. • Optimized electron structure affords TCy5-I-3F abundant ROS to destroy cancer cells. • Dual targeting ability and abundant ROS trigger the multiple pharmacological mechanisms for cancer treatment. • The multiple targeting design and corresponding mechanisms provide a new insight for efficient photodynamic therapy. The excessive production of reactive oxygen species (ROS) can damage the mitochondrial membrane and induce apoptosis, causing endoplasmic reticulum stress and triggering immunogenic cell death. Therefore, the combination of apoptosis and immunogenic death by the dual-targeted ROS generator has great potential to address inefficient cancer treatment. A near-infrared photosensitizer was developed for efficient ROS production and dual-targeted cancer treatment. Due to the modulation of electron structure, the reduced transition energy barrier affords TCy5-I-3F the highest efficiency to produce ROS. TCy5-I-3F has excellent mitochondrial and endoplasmic reticulum targeting ability, causing cell apoptosis and stress of the endoplasmic reticulum for destroying cancer cells. In the dual-targeted mode, high expression of GRP780, activation of heat shock protein (HSP70), the outflow of high mobility group protein B1, efflux of Calreticulin, and massive efflux of adenosine triphosphate are evaluated in the pharmacological experiments. In vivo experiments, the maturation of dendritic cells (DC, CD80+, CD86+), CD8+ T cells and CD3+ T cells also highlights the effectiveness. The tumors of mice treated with TCy5-I-3F and near-infrared (NIR) light are significantly inhibited. The multifunctional targeting design and corresponding mechanisms prove a new insight for exploring efficient photodynamic therapy drugs. [ABSTRACT FROM AUTHOR]

Late embryogenesis abundant (LEA) proteins comprise a large family that plays important roles in the regulation of abiotic stress, however, no in-depth analysis of LEA genes has been performed in grapevine to date. In this study, we analyzed a total of 52 putative LEA genes in grapevine at the genomic and transcriptomic level, compiled expression profiles of four selected (V. amurensis) VamLEA genes under cold and osmotic stresses, and studied the potential function of the V. amurensis DEHYDRIN3 (VamDHN3) gene in grapevine callus. The 52 LEA proteins were classified into seven phylogenetic groups. RNA-seq and quantitative real-time PCR results demonstrated that a total of 16 and 23 VamLEA genes were upregulated under cold and osmotic stresses, respectively. In addition, overexpression of VamDHN3 enhanced the stability of the cell membrane in grapevine callus, suggesting that VamDHN3 is involved in osmotic regulation. These results provide fundamental knowledge for the further analysis of the biological roles of grapevine LEA genes in adaption to abiotic stress. [ABSTRACT FROM AUTHOR]

This paper investigates the containment control problem for a class of partial differential multi-agent systems, which are governed by the parabolic equations (heat equations) or the second-order hyperbolic equations (wave equations). The distributed containment-based feedback control laws are obtained by constructing an appropriate Lyapunov functional, and under the action of the feedback control laws, the containment errors between the followers ′ states and the convex hull spanned by the leaders ′ states on an appropriate Sobolev space can converge to zero as time tends to infinity. Simulation examples are finally used to show the effectiveness of the theoretical analysis. • Put forward the containment control problem of partial differential MASs. • Apply the Lyapunov functional approach. • The partial differential MASs are governed by the most important PDEs. [ABSTRACT FROM AUTHOR]

Summary: Cold stress is a major limiting factor in grape (Vitis) productivity. In this study, we characterized a cold‐responsive ethylene response factor (ERF) transcription factor, VaERF092, from Amur grape (Vitis amurensis). VaERF092 expression was induced by both low temperatures and the ethylene precursor 1‐aminocyclopropane‐1‐carboxylate (ACC), but was suppressed by treatment with the ethylene inhibitor aminoethoxyvinylglycine (AVG) under cold conditions. Ectopic expression of VaERF092 in Arabidopsis thaliana enhanced cold tolerance. Co‐expression network analysis of V. vinifera genes indicated that WRKY33 might be a downstream target of VaERF092. This hypothesis was supported by the fact that VaWRKY33 was expressed temporally after VaERF092 expression and could also be induced by cold and ACC, and inhibited by AVG. Yeast one‐hybrid, transient β‐glucuronidase (GUS) and dual‐luciferase reporter assays provided evidence for an interaction between VaERF092 and a GCC‐box element in the VaWRKY33 promoter. In addition, heterologous overexpression of VaWRKY33 in A. thaliana resulted in enhanced cold tolerance. VaERF092‐ and VaWRKY33 overexpressing grape calli showed lower low‐temperature exothermic values than the empty vector (EV) calli, indicating enhanced tolerance to cold. Together, these results indicated that VaERF092 regulates VaWRKY33 through binding to its promoter GCC‐box, leading to enhanced cold stress tolerance. Significance Statement: Our study revealed that ethylene response factor VaERF092 regulated VaWRKY33 through binding to its promoter GCC‐box, leading to enhanced cold tolerance. This finding may provide a model responding to cold stress in plants. [ABSTRACT FROM AUTHOR]

Wu, Z.; Xiang, Y.; Li, M.; Iqbal, M., and Xu, G, 2019. Investigation of accumulator main parameters of hydraulic excitation system. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 613–622. Coconut Creek (Florida), ISSN 0749-0208. The accumulator is a special container which used for accumulate energy and its responsiveness plays an important role in improving hydraulic system performance. Therefore, it can be seen from the current research results that most scholars focus on the bladder-type accumulator owing to the reflection of the bladder-type accumulator is fast. The hydraulic system with a bladder-type accumulator is adapted to absorb shock pressure and eliminate pressure pulsations. However, due to the sudden change of the reversing valve or the sudden stop of the actuator, the pressure shock will occur in the hydraulic system, and the relief valve will not be able to move, which will cause the pipeline to vibrate. In severe cases, the hydraulic pipe will be broken and caused a safety accident. In actual use, the effect of absorbing pressure shock is not ideal due to improper selection of accumulator parameters. Therefore, the main objective of this study is to use theoretical analysis, computer simulation and experimental research to analyse the influence of accumulator parameters on the hydraulic system. [ABSTRACT FROM AUTHOR]

Wu, Z.; Xiang, Y.; Li, M.; Iqbal, M., and Xu, G, 2019. Investigation of accumulator main parameters of hydraulic excitation system. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 613–622. Coconut Creek (Florida), ISSN 0749-0208. The accumulator is a special container which used for accumulate energy and its responsiveness plays an important role in improving hydraulic system performance. Therefore, it can be seen from the current research results that most scholars focus on the bladder-type accumulator owing to the reflection of the bladder-type accumulator is fast. The hydraulic system with a bladder-type accumulator is adapted to absorb shock pressure and eliminate pressure pulsations. However, due to the sudden change of the reversing valve or the sudden stop of the actuator, the pressure shock will occur in the hydraulic system, and the relief valve will not be able to move, which will cause the pipeline to vibrate. In severe cases, the hydraulic pipe will be broken and caused a safety accident. In actual use, the effect of absorbing pressure shock is not ideal due to improper selection of accumulator parameters. Therefore, the main objective of this study is to use theoretical analysis, computer simulation and experimental research to analyse the influence of accumulator parameters on the hydraulic system. [ABSTRACT FROM AUTHOR]

Summary: The Thévenin equivalent model for half‐bridge modular multilevel converters on electromagnetic transient simulation, applying 2‐state resistances to represent switches and adopting Dommel's algorithm to get a discretized capacitance in each submodule, achieves good central processing unit time saving while maintaining the identity of every submodule. But the large number of changeable resistances still brings a computational challenge for simulation efficiency, because the admittance matrix gets an equaled size to the amount of nodes, and inverts (re‐triangularizes) each time when a switch performs. This paper presents a novel fixed topology Thévenin equivalent half‐bridge modular multilevel converter integral model and simplifies its mathematical expression markedly. The choice of integration methods is also performed by discussion of the stability, and backward Euler algorithm is selected for further speedup. Basically, it achieves speedup by (1) the use of novel Thévenin equivalent model to achieve unchangeable admittance matrix while regarding the switches as excitations; (2) merging the elements (inductances, resistances, and submodules) in the arm of modular multilevel converter by Thévenin equivalent to reduce the order of admittance matrix; (3) simplifying the mathematica expression of sub module by Thévenin equivalent and omitting the small resistance; and (4) the use of backward Euler algorithm to discretize all the elements (capacitances, inductances, resistances, and submodules) in the circuit for a better convergence speed and larger speedup factor. The model is implemented in a 3‐phase grid‐connected modular multilevel converter circuit; the results show that the proposed Thévenin equivalent integral model makes a good accuracy on simulating the performances of the half‐bridge modular multilevel converter with drastically reduced computational time. [ABSTRACT FROM AUTHOR]