62 research outputs found

    On the pinning strategy of complex networks

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    In pinning control of complex networks, a tacit believing is that the system dynamics will be better controlled by pinning the large-degree nodes than the small-degree ones. Here, by changing the number of pinned nodes, we find that, when a significant fraction of the network nodes are pinned, pinning the small-degree nodes could generally have a higher performance than pinning the large-degree nodes. We demonstrate this interesting phenomenon on a variety of complex networks, and analyze the underlying mechanisms by the model of star networks. By changing the network properties, we also find that, comparing to densely connected homogeneous networks, the advantage of the small-degree pinning strategy is more distinct in sparsely connected heterogenous networks

    Experimental Investigation of Pedestrian Dynamics in Circle Antipode Experiments

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    To explore the pedestrian motion navigation and conflict reaction mechanisms in practice, we organized a series of circle antipode experiments. In the experiments, pedestrians are uniformly initialized on the circle and required to leave for their antipodal positions simultaneously. On the one hand, a conflicting area is naturally formulated in the center region due to the converged shortest routes, so the practical conflict avoidance behaviors can be fully explored. On the other hand, the symmetric experimental conditions of pedestrians, e.g., symmetric starting points, symmetric destination points, and symmetric surroundings, lay the foundation for further quantitative comparisons among participants. The pedestrian trajectories in the experiments are recognized and rotated, and several aspects, e.g., the trajectory space distribution, route length, travel time, velocity distribution, and time-series, are investigated. It is found that: (1) Pedestrians prefer the right-hand side during the experiments; (2) The route length follows a log-normal distribution, the route potential obeys an exponential distribution, and travel time as well as speed are normally distributed; (3) Taking the short routes unexpectedly cost pedestrians plenty of travel time, while detours seem to be time-saving

    Compressive Strength, Chloride Permeability, and Freeze-Thaw Resistance of MWNT Concretes under Different Chemical Treatments

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    This study investigated compressive strength, chloride penetration, and freeze-thaw resistance of multiwalled carbon nanotube (MWNT) concrete. More than 100 cylindrical specimens were used to assess test variables during sensitivity observations, including water-cement ratios (0.75, 0.5, and 0.4) and exposure to chemical agents (including gum arabic, propanol, ethanol, sodium polyacrylate, methylcellulose, sodium dodecyl sulfate, and silane). To determine the adequate sonication time for MWNT dispersal in water, the compressive strengths of MWNT concrete cylinders were measured after sonication times ranging from 2 to 24 minutes. The results demonstrated that the addition of MWNT can increase the compressive strength of concrete by up to 108%. However, without chemical treatment, MWNT concretes tend to have poor freeze-thaw resistance. Among the different chemical treatments, MWNT concrete treated with sodium polyacrylate has the best compressive strength, chloride resistance, and freeze-thaw durability

    Ursodeoxycholic Acid Inhibits Glioblastoma Progression via Endoplasmic Reticulum Stress Related Apoptosis and Synergizes with the Proteasome Inhibitor Bortezomib

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    Ursodeoxycholic acid (UDCA) has demonstrated cancer suppressive potential in several tumors. Here, we investigated the antitumor potential and biochemical mechanism of UDCA on glioblastoma multiforme (GBM), the deadliest form of brain cancer with a median survival of 15 months. Cell viability was assessed using the CCK-8 and colony forming assays. Expression profiles were obtained using RNA sequencing, and PCR and Western blot were used to validate changes in related markers at the RNA and protein levels. Flow cytometry was used to examine cell cycle, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS). UDCA inhibited GBM cell viability in a dose- and time-dependent manner. Flow cytometry demonstrated that cells were arrested in the G1 phase and underwent apoptosis. The RNA sequencing results showed UDCA treatment in part targeted gene expression related to mitochondria and endoplasmic reticulum (ER). UDCA indeed led to decreased MMP, overproduction of ROS, and ER stress. Three critical ER stress sensors ATF6, IRE1α, and PERK were increased in the acute phase. Additionally, combining UDCA with the proteasome inhibitor bortezomib (BTZ) achieved a synergistic effect through enhancing the PERK/ATF4/CHOP pathway and protracting ER stress. UDCA inhibited GBM progression, and the combination with BTZ achieved a synergistic effect via protracted ER stress. Thus, UDCA, alone or with combination of BTZ, shows promise as a possible therapeutic agent for the treatment of GBM.acceptedVersio

    Resibufogenin Targets the ATP1A1 Signaling Cascade to Induce G2/M Phase Arrest and Inhibit Invasion in Glioma

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    Resibufogenin (RB) is a major active ingredient in the traditional Chinese medicine Chansu and has garnered considerable attention for its efficacy in the treatment of cancer. However, the anticancer effects and underlying mechanisms of RB on glioblastoma (GBM) remain unknown. Here, we found that RB induced G2/M phase arrest and inhibited invasion in a primary GBM cell line, P3#GBM, and two GBM cell lines, U251 and A172. Subsequently, we demonstrated that RB-induced G2/M phase arrest occurred through downregulation of CDC25C and upregulation of p21, which was caused by activation of the MAPK/ERK pathway, and that RB inhibited GBM invasion by elevating intercellular Ca2+ to suppress the Src/FAK/Paxillin focal adhesion pathway. Intriguingly, we confirmed that upon RB binding to ATP1A1, Na+-K+-ATPase was activated as a receptor and then triggered the intracellular MAPK/ERK pathway and Ca2+-mediated Src/FAK/Paxillin focal adhesion pathway, which led to G2/M phase arrest and inhibited the invasion of GBM cells. Taken together, our findings reveal the antitumor mechanism of RB by targeting the ATP1A1 signaling cascade and two key signaling pathways and highlight the potential of RB as a new class of promising anticancer agents.publishedVersio

    A wearable fiber-optic sensor for monitoring human elbow and wrist joint motion

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    This article describes a wearable sensor for monitoring the motion of human elbow and wrist joints. The sensor converts the joint motion angle into a displacement, which is monitored using a fiber-optic sensor based on reflective light intensity modulation. A mathematical model is established, and the potential influencing factors of the sensor are investigated. Two prototypes for elbow and wrist joint angle monitoring are fabricated and validated. The experimental results indicate that the proposed sensor has a measurement range of 0–60° (0–120°), with a resolution of 0.338° (3.6°) for monitoring the wrist joint palm flexion (elbow joint flexion). The proposed sensor has the potential to be used for rehabilitation purposes and monitoring of joint angles while performing reaching tasks, which are the most common upper-limb gestures

    MAPK1 promotes the metastasis and invasion of gastric cancer as a bidirectional transcription factor

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    Background: The Mitogen-activated protein kinase 1 (MAPK1) has both independent functions of phosphorylating histones as a kinase and directly binding the promoter regions of genes to regulate gene expression as a transcription factor. Previous studies have identified elevated expression of MAPK1 in human gastric cancer, which is associated with its role as a kinase, facilitating the migration and invasion of gastric cancer cells. However, how MAPK1 binds to its target genes as a transcription factor and whether it modulates related gene expressions in gastric cancer remains unclear. Results: Here, we integrated biochemical assays (protein interactions and chromatin immunoprecipitation (ChIP)), cellular analysis assays (cell proliferation and migration), RNA sequencing, ChIP sequencing, and clinical analysis to investigate the potential genomic recognition patterns of MAPK1 in a human gastric adenocarcinoma cell-line (AGS) and to uncover its regulatory effect on gastric cancer progression. We confirmed that MAPK1 promotes AGS cells invasion and migration by regulating the target genes in different directions, up-regulating seven target genes (KRT13, KRT6A, KRT81, MYH15, STARD4, SYTL4, and TMEM267) and down-regulating one gene (FGG). Among them, five genes (FGG, MYH15, STARD4, SYTL4, and TMEM267) were first associated with cancer procession, while the other three (KRT81, KRT6A, and KRT13) have previously been confirmed to be related to cancer metastasis and migration. Conclusion: Our data showed that MAPK1 can bind to the promoter regions of these target genes to control their transcription as a bidirectional transcription factor, promoting AGS cell motility and invasion. Our research has expanded the understanding of the regulatory roles of MAPK1, enriched our knowledge of transcription factors, and provided novel candidates for cancer therapeutics

    A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

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    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others

    Design and performance characterization of a soft robot hand with fingertip haptic feedback for teleoperation

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    A soft robot hand with fingertip haptic feedback for teleoperation is proposed to perform complex tasks and ensure safe and friendly human-machine interaction. This robot hand can perform finger flexion/extension and abduction/adduction motions. A data glove is used to collect the hand joint angle data of the operator. Flexion sensors are embedded in the soft robot hand to monitor the bending angles of the actuators. Pressure sensors on the fingertips of the robot hand collect contact force data, and haptic feedback actuators located on the fingertips of the operator display the contact force to the operator. Characterization tests and teleoperation performance tests involving human participants are performed to prove the feasibility of the soft robot hand. The soft robot hand prototype satisfies the output force requirements and can meet 96.86% of the design requirements of the joint angles. The soft robot hand can be teleoperated to perform nine commonly used motions in daily operational tasks. The success rates of fingertip force discrimination, grasp, and pinch ability experiment are 100%, 95.00%, and 98.33%, respectively. The results of the experiment suggest that the soft robot hand with fingertip haptic feedback can perform complex tasks in teleoperation
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