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Accurately predicting the remaining useful life (RUL) of equipment is crucial for planning production and eliminating unplanned downtime events. Specifically, the application of effective RUL prediction methods can detect potential equipment failures in advance to provide timely maintenance measures, which can help enterprises better plan and manage resources, optimize production plans, and provide strong support for subsequent maintenance decisions. The data-driven approaches have achieved great success in the field of RUL prediction by fully exploiting mechanical degradation information from historical operation data. However, these approaches have certain limitations, for instance, (1) they always fail to precisely extract spatial and temporal features in noisy environments simultaneously; (2) they often fail to effectively capture local features and global degradation trends simultaneously. To overcome the above limitations, we design an end-to-end model, termed ASATCN-TABGRU, for mechanical failure prediction, which contains an automatic shrinking attention temporal convolutional network (ASATCN) and a temporal attention bidirectional gated recurrent unit (TABGRU). In ASATCN module, to extract spatio-temporal information from historical operation data, we first perform a multi-scale modeling of historical operation data through a deliberately designed dilated causal convolution subnetwork (DCCS) to obtain local features. Then, we propose a novel soft thresholding subnetwork (STS) based on the normalization-based attention module (NAM), to capture useful temporal features through the automatic shrinking soft thresholding mechanism from the local features sequence; in addition, we design a hybrid attention subnetwork (HAS) to capture spatial features with flexible and different importance by the spatial-channel attention mechanism from historical operation data. The precise extraction of spatio-temporal features is then achieved through a connection operation. With the above encoded spatio-temporary features sequence, a TABGRU module is further proposed to capture global degradation trends by simultaneously extracting contextual information and historical influence information, thereby effectively modeling the local and global features. The experiments show that our approach has better performance and robustness, compared with other state-of-the-art approaches, particularly on the small sample dataset. [ABSTRACT FROM AUTHOR]

The resilient cooperative source seeking problem of double-integrator multi-robot systems under d-local deception attacks is investigated. In this article, we first propose a resilient cooperative control algorithm and present a necessary and sufficient condition for its achievement of resilient consensus. Then, through applying the particle swarm optimization algorithm to the resilient cooperative control algorithm, a resilient cooperative source seeking algorithm is proposed. We show that this algorithm can solve the source seeking problems under d-local deception attacks with an additional potential of addressing the multiple local extrema case. Finally, the feasibility of the proposed algorithms is illustrated by simulation and experimental results. [ABSTRACT FROM AUTHOR]

Summary: This article considers distributed optimization problems of complex cyber‐physical networks, whose goal is to minimize a global function consisting of a sum of local functions possessed by each node, when the communication network is suffering L‐local deception attacks. After showing that merely 1‐local deception attacks can arbitrarily affect the outcome of any distributed optimization algorithms without being detected, we propose a resilient consensus‐based distributed optimization algorithm, where the estimation for the optimizer of each node is updated according to its subgradient and its partial neighbors' estimation. Then, we provide the conditions for the proposed algorithm to ensure that all the nodes can make an agreement and converge to the convex hull of the local optimizer of their functions in the presence of L‐local deception attacks. Finally, some simulation examples are presented to demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNAs (miRNAs) are a class of endogenous, non-coding, 18–24 nucleotide length single-strand RNAs that could modulate gene expression at post-transcriptional level. Previous studies have shown that miR-128 enriched in the brain plays an important role in the development of nervous system and the maintenance of normal physical functions. Aberrant expression of miR-128 has been detected in many types of human tumors and its validated target genes are involved in cancer-related biological processes such as cell proliferation, differentiation and apoptosis. In this review, we will summarize the roles of miR-128 and its target genes in tumorigenesis and metastasis. [Copyright &y& Elsevier]

Background: Endoscopic third ventriculostomy (ETV) is a developing therapeutic stratagem for obstructive hydrocephalus (OH). The aim of this study was to determine the relevance of third ventricle diagnostic imaging by three-dimensional constructive inference in steady state (3D CISS) MRI in patients with OH and to access the preoperative and postoperative values of this technique in patients undergoing endoscopic third ventriculostomy (ETV). Methods: Forty-six patients with an existing obstruction below the posterior part of the third ventricle underwent 3D CISS sequence MRI on a 1.5 T superconductive MR scanner and were included into this retrospective study. 19 patients were treated with ETV. Regression analysis of the correlation between third ventricle enlargement (TVE) and hydrocephalus degree (HD) and between TVE and third ventricle floor thickness (TVFT) was calculated. In the 19 ETV cases the incisions were marked according to MR images, and the 3D-CISS sequence imaging and the surgical outcome were compared before and after ETV. Results: By virtue of 3D-CISS 97.83% third ventricle floors and 91.30% basilar arteries (BA) could be visualized, and there was a positive correlation between TVE and HD and a negative correlation between TVE and TVFT in this group. All incision sites on the scalp could be marked correctly. The degree of enlargement of the third ventricle allowed a prediction of the technical challenge to puncture the third ventricle floor. The position and route of BA could be demonstrated avoiding intraoperative iatrogenic lesions. At follow-up, 100% of the fistulas of the third ventricle floor could be measured on 3D-CISS images. The mean diameter of the fistulas was 6.12 ± 0.96 mm; in 91.67%, new CSF fluid directions could be demonstrated; in 83.33%, enlarged ventricle system got withdrawn, and 91.67% patients showed relief of initial symptoms. 1 patient needed the implantation of a ventriculoperitoneal shunt 7 months after EVT. The preoperative HD compared with postoperative HD (P < .01); the preoperative TVE compared with postoperative TVE (P < .05). Conclusion: Images of the 3D-CISS sequence on MRI can visualize the third ventricle accurately and provide a reliable method for the evaluation of ETV pre- and postoperatively. The degree of enlargement of the third ventricle in patients with obstructive hydrocephalus is associated with the thickness of third ventricle floor and allows a prediction of the difficulty to puncture in ETV. [ABSTRACT FROM AUTHOR]

Telomerase is a reverse transcriptase that adds repeats of a six-base DNA sequence to chromosome ends and thereby prevents their shortening during successive cell divisions. Telomerase activity and expression of the catalytic subunit of telomerase (TERT) are high in brain cells during embryonic development, but are undetectable in the adult. We now report that telomerase activity and expression of TERT are induced in the hippocampus of adult mice after administration of the seizure-inducing excitotoxin kainate. Telomerase activity is present at 24 h and 7 days after kainate administration, but is no longer detectable at 4 weeks. Because the time course of telomerase induction was similar to the time course of microglial activation, we performed studies to determine whether microglia were the source of the telomerase activity. Examination of brain sections immunostained with a TERT antibody and an antibody against a microglia-specific antigen revealed that TERT was not detectable in the uninjured brain, and was present in microglia 24 h and 7 days after kainate administration. This is the first evidence that telomerase can be induced by brain injury and the first evidence that TERT can be expressed in microglia, suggesting roles for telomerase in microglial responses to brain injury. [Copyright &y& Elsevier]

Abstract: The catalytic subunit of telomerase (TERT) is a specialized reverse transcriptase that has been associated with cell immortalization and cancer. It was reported recently that TERT is expressed in neurons throughout the brain in embryonic and early postnatal development, but is absent from neurons in the adult brain. We now report that suppression of TERT levels and function in embryonic mouse hippocampal neurons in culture using antisense technology and the telomerase inhibitor 3' -azido-2' 3' -dideoxythymidine significantly increases their vulnerability to cell death induced by amyloid β-peptide, a neurotoxic protein believed to promote neuronal degeneration in Alzheimer's disease. Neurons in which TERT levels were reduced exhibited increased levels of oxidative stress and mitochondrial dysfunction following exposure to amyloid β-peptide. Overexpression of TERT in pheochromocytoma cells resulted in decreased vulnerability to amyloid β-peptide-induced apoptosis. Our findings demonstrate a neuroprotective function of TERT in an experimental model relevant to Alzheimer's disease, and suggest the possibility that restoration of TERT expression in neurons in the adult brain may protect against age-related neurodegeneration. [ABSTRACT FROM AUTHOR]

Excitotoxicity, a form of neuronal injury in which excessive activation of glutamate receptors results in cellular calcium overload, has been implicated in the pathogenesis of Alzheimer disease (AD), although direct evidence is lacking. Mutations in the presenilin-1 (PS1) gene on chromosome 14 are causally linked to many cases of early-onset inherited AD (refs. 5,6). We generated PS1 mutant mice (PS1M146VKI) that express the PS1 M146V targeted allele at normal physiological levels. Although PS1M146VKI mice have no overt mutant phenotype, they are hypersensitive to seizure-induced synaptic degeneration and necrotic neuronal death in the hippocampus. Cultured hippocampal neurons from PS1M146VKI mice have increased vulnerability to death induced by glutamate, which is correlated with perturbed calcium homeostasis, increased oxidative stress and mitochondrial dysfunction. Agents that suppress calcium influx or release and antioxidants protect neurons against the excitotoxic action of the PS1 mutation. These findings establish a direct link between a genetic defect that causes AD and excitotoxic neuronal degeneration, and indicate new avenues for therapeutic intervention in AD patients. [ABSTRACT FROM AUTHOR]

This paper considers the interval consensus problems of discrete-time multi-agent systems over random interaction networks, where each agent can impose a lower and an upper bound, i.e., a local constraint interval, on the achievable consensus value. We show that if the intersection of the intervals is nonempty, it holds as a sure event that the states of all the agents converge to a common value inside that intersection, i.e., the interval consensus can be achieved almost surely. Convergence analysis is performed through developing a robust consensus analysis of random networks in view of a martingale convergence lemma. Numerical examples are also exhibited to verify the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

A 2D higher-order alternating-direction-implicit (ADI) finite-difference time-domain method based on a compact scheme is presented in this paper. This compact ADI method improves the efficiency of computation by reducing the bandwidth of the matrix to be inversed from seven to five for the 4th-order scheme. The method is proved to be unconditionally stable and its dispersion analysis is also presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 273–275, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20609 [ABSTRACT FROM AUTHOR]

Abstract A coordination control of multiple generic linear homogeneous agents under arbitrary network topology with uniform and fixed time delay is proposed in this paper. From the network topology, the agents are categorized into two groups: those within the closed strong components (group 1) and those outside the closed strong components (group 2). It is shown that under allowable delay bound, the agents of group 1 reach synchronization while the agents of group 2 converge asymptotically to the convex hull spanned by the synchronized agents of group 1. The technique of semi-discretization is applied for computing the delay bound. For a specific time delay, the method is also feasible in finding an optimal coordination control gain with the fastest decay rate. A linear matrix inequality method is also given to show an alternative way to find the maximum allowable delay bound. An illustrative simulation is presented to validate our obtained theoretical results. [ABSTRACT FROM AUTHOR]

This article investigates a bounded cluster synchronization problem of dynamical systems, which can be of the generic linear type or Lipschitz nonlinear type, over directed switching network. Each cluster is equipped with a virtual leader which produces the desired trajectory for the agents to track. It is required only a fraction of systems is influenced by the leader. The interaction topology, which describes the information exchange among the dynamical systems as well as the virtual leaders, is allowed to be time varying with a well-defined average over an infinite horizon. That is, each augmented cluster, consisting of the agents as well as the corresponding virtual leader, in the time-average network topology is required to have a directed spanning tree. We then transform the cluster synchronization problem into a stability problem via the averaging method. It is proved that the convergence property for both types of dynamical systems is exclusively determined by the averaging system if the network topology switches sufficiently fast compared to original systems. Finally, it is concluded that if the intracluster coupling strength of the time-average topology is stronger than a threshold, then bounded cluster synchronization can be realized for a fast switching linear or nonlinear systems. Two examples are provided to verify our results. [ABSTRACT FROM AUTHOR]

This paper studies the price-based demand response problem in a deregulated retail electricity trading, aiming to coordinate the energy consumption behavior of end-users under dynamic retail prices. The challenge here is that in addition to the hierarchical decision-making process between utility company and end-users considered in existing works, the non-cooperative and competitive interdependence among end-users cannot be ignored. To address this issue, we first construct a novel Stackelberg–Nash game, in which the Stackelberg game is used to capture the hierarchical decision-making process between utility company and end-users, while the Nash game is dedicated to describing the interdependence among end-users. Then the existence and uniqueness of the Stackelberg–Nash equilibrium is provided along with theoretical analysis. On the basis of the analysis of equilibrium, we propose a distributed iterative algorithm with an adaptive step size, which is benchmarked with a fixed step-size algorithm. The comparison results on a real-life residential retail electricity market show that our proposed algorithm has better performance in terms of effectiveness and scalability. • Develop a Stackelberg—Nash game model to characterize the interactive relationship. • Proof the existence and uniqueness of Stackelberg–Nash equilibrium. • Propose a distributed iterative algorithm with an adaptive step size. [ABSTRACT FROM AUTHOR]

This paper investigates the group synchronization problem for interacting clusters of agents, which can be either generic linear systems or nonlinear oscillators, by focusing on in-depth understanding of how the couplings among agents influence the group behavior. To this end, we work on both the homogeneous case that agents have the same system dynamics and the heterogeneous case that agents from different clusters have different system dynamics. It is shown that the synchronization for each cluster of agents is irrelevant to the strength of the intercluster couplings as long as the intercluster couplings are collectively acyclic; that is, the intercluster couplings do not incur desynchronization and, thus, no extra effort beyond the strengths of the intracluster couplings, which are necessary to guarantee the synchronization of each cluster in the absence of intercluster couplings, are needed. Moreover, we provide an example demonstrating that the condition of having collectively acyclic intercluster couplings is not a necessity in guaranteeing the above property. [ABSTRACT FROM AUTHOR]

• A mayonnaise-like Pickering emulsion was stabilized by pea protein isolate microgels. • NaCl increased droplet size and sucrose improved emulsion's viscosity. • The plant-scaled egg-free mayonnaise has a 99.8% thixotropic recovery. • Lab and plant produced emulsions have similar viscosity to commercial mayonnaise. Particle stabilized O/W Pickering emulsion has great potential for making egg-free mayonnaise. In this study, we fabricated pea protein isolate (PPI) microgels by gel-breaking method and applied in mayonnaise-like Pickering emulsion. The effects of acetic acid (pH), sodium chloride (NaCl), and sucrose, which are typically used in commercial mayonnaise were studied. The minimum droplet size (47.0 μm) was found below isoelectric point. The NaCl decreased ζ-potential to almost 0 and risen droplet size to 75.9 μm. The sucrose enhanced the emulsion's viscosity while lowering thixotropic recovery rate. Based on droplet size, viscosity, thixotropic recovery, and microstructure; 350 mmol NaCl and 4 wt% sucrose was finally used to make egg-free mayonnaise-like Pickering emulsion, and showed similar properties compared with commercial mayonnaise, and the thixotropy recovery rate was near 100%. A plant-scale test further confirmed the feasibility. The results showed the PPI microgels had a strong application prospect to form egg-free mayonnaise. [ABSTRACT FROM AUTHOR]

Chronic infection with Schistosoma japonicum is an important cause of hepatic fibrosis (HF). Human 9q33.3 is one of the most important loci for stress-related diseases. We examined the potential associations of 43 single-nucleotide polymorphisms (SNPs) with S. japonicum infection and HF in epidemic region in China. We identified a SNP (rs10118570 GG in mitogen-activated protein kinase associated protein 1, MAPKAP1) contributes to anti-infection (adjusted OR = 0.35) and anti-fibrogenesis (adjusted RR = 0.44) in the discovery study. Replicative and combined studies showed consistent protective quality for this genotype (replicative: adjusted OR = 0.37 for anti-infection, and adjusted RR = 0.40 for anti-fibrogenesis; Combined: adjusted OR = 0.45 for anti-infection, and adjusted RR = 0.42 for anti-fibrogenesis). Univariate and multivariate analysis in the discovery, replicative and combined studies, suggested that durations (years), splenomegaly, serum ALB and rs10118570 were independent predictors influencing the fibrogenesis. The analysis of gene-gene interaction showed rs10118570 functions independently. We conclude that MAPKAP1 may represent a novel anti-infection and anti-fibrogenesis genomic locus in chronic schistosomiasis japonica. And rs10118570 may be a potential biomarker and target for the treatment of this life-threatening ancient disease. [ABSTRACT FROM AUTHOR]

Glucose-regulated protein 78 (GRP78) is one of the most important responders to disease-related stress. We assessed the association of the promoter polymorphisms of GRP78 with risk of hepatocellular carcinoma (HCC) and GRP78 expression in a Chinese population. We examined 1007 patients undergoing diagnostic HCC and 810 unrelated healthy controls. Mechanisms by which the GRP78 promoter polymorphism modulates HCC risk and GRP78 levels were analyzed. The promoter haplotype and diplotype carrying rs391957 (−415bp) allele G and genotype GG was strongly associated with HCC risk. Luciferase reporter assays indicated that the promoter carrying rs391957 allele G (haplotype GCCd) showed increased activity in HepG2 cells and Hela cells. rs391957 was also shown to increase the affinity of the transcriptional activator Ets-2, the resistance to apoptosis, as well as cell instability in stressful microenvironment. Furthermore, compared with allele A, rs391957 allele G was associated with higher levels of GRP78 mRNA and protein in HCC tissues. These findings provided new insights into the pathogenesis of HCC and an unexpected effect of the interaction between rs391957 and Ets-2 on hepatocarcinogenesis, and especially supported the hypothesis that stress-related and evolutionarily conserved genetic variant(s) influencing transcriptional regulation could predict susceptibilities. [ABSTRACT FROM PUBLISHER]

The objective of the study was to evaluate the effectiveness of the supraorbital "keyhole" approach with endoscope assistance in surgical treatment of benign tumors around the sellar region. Thirty-five patients, including 19 pituitary tumors, 11 craniopharyngiomas and five tuberculum sellae meningiomas, were enrolled in this study. The tumors were resected through an endoscope-assisted supraorbital keyhole approach via a small skin incision within the eyebrow. Complete removal of the sellar region tumors was achieved in all 35 cases by endoscope-assisted supraorbital keyhole approach. Mean length of hospital stay after surgery was 10.2 days (range 5 - 17). There was no patient with evidence of residual or recurrent tumor during the follow-up period. There was no infection, bleeding, further vision impairment, oculomotor nerve injury or other cranial nerve injury symptom owing to surgery. Though some patients suffered from insipidus, hyperprolactinemia, subcutaneous edema or other postoperative complications, they eventually recovered with or without drug administration. The supraorbital "keyhole" approach with endoscopic assistance in the surgical treatment of benign tumors around the sellar region is an ideal pattern. [ABSTRACT FROM AUTHOR]