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Summary: This paper investigates group consensus tracking problems with time‐varying reference velocities. The multiple agents are described as second‐order nonlinear dynamics in directed information exchange settings. For the multi‐agent networks formed by finite agent groups, novel distributed protocols with/without time‐varying transmission delays are designed to solve the group consensus tracking problems. The problems are first transformed into the asymptotical stability of consensus error systems and the input‐to‐state stability of tracking error systems, and then sufficient conditions are derived to guarantee the agents realizing the group consensus tracking based on Lyapunov stability theories. Finally, several simulations are given to verify the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper studies the bipartite consensus tracking problems of fractional-order multi-agent systems on directed signed graphs. Each agent is modelled as a second-order fractional-order dynamics with the order belonging to $ (0,1] $ (0 , 1 ] , and the cooperative and competitive interactions between the agents coexist in the systems. Two distributed bipartite consensus tracking protocols are proposed for the systems based on continuous information and sampled information, respectively. Under the assumption that the directed signed graph is structurally balanced, it is shown that the second-order fractional-order multi-agent systems can achieve the bipartite consensus tracking if the feedback coefficients are chosen appropriately. Finally, several simulations are provided to verify the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

CO2 emissions from fossil energy have caused global climate problems and threatened human survival. However, there are few studies on the spatiotemporal distribution and driving factors of carbon emissions. This paper takes the Yangtze River Delta (YRD) urban agglomeration as the research object and analyzes the spatiotemporal heterogeneity of carbon dioxide emissions and their driving factors from 2000 to 2017. First, a series of preprocessing, such as resample, interpolation, and image clipping, are conducted on the CO2 emission data and nighttime light remote sensing images. Second, the dynamic time wrapping (DTW) and hierarchical clustering algorithms were involved in manipulating the CO2 emission data. Consequently, the cities' and CO2 emissions' time series were classified into four categories and three stages separately. Finally, the geographical detector model (GDM) and geographical and temporal weighted regression (GTWR) are coupled to evaluate the spatiotemporal heterogeneity and quantify the driving factors. The results show the following: (1) The spatiotemporal distribution of CO2 emissions has spatial consistency from 2000 to 2017. High-emission areas are concentrated in economically developed areas such as Shanghai, Suzhou, and Wuxi. The results are consistent with previous research. (2) Regional aggregation is a revealed new trend. CO2 emissions in the target urban areas are gradually converging into economic center cities and diverse class cities, e.g., Shanghai and Ningbo. (3) In cities of different economic development levels, the driving factors of CO2 emissions are different. The secondary sector and urban infrastructure dominate in the early stages of developed cities. On top of that, the influence of the tertiary industry is more significant in the later development stages. According to the results, in the urban development process, humans should not only pursue the increase in speed but also pay attention to the negative impact of the economic development process on the ecological environment. Besides, since the spatiotemporal characteristics and dominant factors of urban carbon emissions are different in each stage of development, the formulation of carbon reduction policies should be associated with urban features. [ABSTRACT FROM AUTHOR]

The relationship between landslide area and volume has been shown to obey to a power law with a scaling exponent α varying from 1.1 to 1.6. This paper presents a three-dimensional upper bound method of limit analysis to evaluate the scaling exponent for the power-law relationship between source area and source volume of incipient rotational failure in soils. Based on an ensemble of data from calculated 20,000 theoretical homogenous slopes, the relations between landslide area and volume are calculated on a statistical basis and two fitting forms are systemically analyzed. Form 1, which gives the area-volume relations directly, shows an excellent agreement with field observations, with the scaling exponent α equal to 1.40. Form 2, considering the soil materials, is more suitable for the analysis of landslides affecting artificial homogeneous slopes. Three kinds of failure surface geometries, i.e., deep, intermediate, and face failure are discussed. The parametric study illustrates that the failure surface geometry affects the scaling exponent within a limit range. Further, the proposed method reveals that if the hillslope inclination, internal friction angle, and hillslope relative width are determined, the geometry of the landslide shows self-similar behavior, otherwise, the behavior is self-affine. [ABSTRACT FROM AUTHOR]

We investigate scaled group consensus problems of high-order multi-agent systems with directed information exchanges. As one of multiple consensus, the scaled group consensus focuses on both cooperations and competitions among multi-agent sub-networks and cooperations among agents belonging to a sub-network. Two distributed protocols are designed to solve the scaled group consensus problems. The (generalised) Routh–Hurwitz stability criterion and matrix theory are utilised to establish necessary and sufficient conditions guaranteeing the agents reaching the scaled group consensus. Finally, several simulations are presented to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Abstract Human Glioblastoma is one deadly disease; the median survival time is reported to be 13.9 months after treatment. In the present study, we discovered that DHX33 is highly expressed in 84% of all Glioblastoma multiforme (GBM). Knockdown of DHX33 led to significant reduced proliferation and migration in glioblastoma cells in vitro and in vivo. Mechanistically, DHX33 regulated a set of critical genes involved in cell cycle and cell migration to promote glioblastoma development. Additionally, DHX33 was found to be induced by inhibitors of PI3K and mTOR whose activation has been detected in 50% of glioblastoma. Overexpression of wild type DHX33 protein, but not the helicase dead mutant, confers resistance to mTOR inhibitors in glioblastoma cells. DHX33 probably functions as a critical regulator to promote GBM development. Our results highlight its therapeutic potential in treating GBM. Highlights • DHX33 is highly expressed in 84% of human Glioblastoma Multiforme (GBM). • DHX33 is pivotal to maintain cell proliferation and migration in glioblastoma cells through regulating a subset of genes. • DHX33 can be induced by PI3K/mTOR inhibitors and confers resistance to mTOR inhibition. [ABSTRACT FROM AUTHOR]

This paper investigates a couple-group consensus problem of second-order multi-agent systems with the impact of second-order neighbours’ information. For systems with/without time delays, couple-group consensus criteria are established in the form of linear matrix inequalities by utilizing both model transformation and stability theories. The main results indicate that the group consensus for multi-agent systems under the effect of second-order neighbours’ information can be achieved based on the premise of a generalized balanced couple. Finally, illustrative examples are presented to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Objective This study intended to explore the molecular mechanism of RUNX3 in inhibiting the process of migration and proliferation of gastric cancer (GC) cells. Methods The overexpressed plasmids of RUNX3 and the interfering siRNA of RUNX3 were transfected into GC cells. Then, qRT-PCR and western blot were performed to identify the expression level of RUNX3 and miR-182 in tumors and adjacent tissues respectively. ChIP and luciferase assay were performed to detect the relationship between RUNX3 and miR-182 as well as miR-182 and HOXA9 . Furthermore, EdU assay were used to investigate the proliferation of GC cells, Transwell assay and wound healing assay were utilized to assess cell metastasis. Xenograft mouse model was set to evaluate the proliferation in vivo . Results The results of qRT-PCR and western blot indicated that RUNX3 could regulate the expression of miR-182. RUNX3 can be straightly interacted with the promoter region of miR-182 in accordance with the results of ChIP. Luciferase assay revealed that HOXA9 was the direct target gene of miR-182. In addition, EdU proliferation, wound healing assay and transwell assay showed that miR-182 mimics and HOXA9 siRNA could inhibit the ability of cells proliferation, migration and invasion. The findings of in vivo experiments strongly supported the view that miR-182/ HOXA9 was involved in the process of RUNX3 -mediated GC tumor growth. Conclusions RUNX3 could impede the ability of GC cells proliferation, migration and invasion by modulating miR-182/ HOXA9 pathway. [ABSTRACT FROM AUTHOR]

This paper addresses group consensus for multi-agent systems with switching topologies and time-varying delays, where all agents are described by discrete-time second-order dynamics. Based on the relationship between zero/nonzero in-degree graphs and nonnegative matrices group consensus criteria, which is presented in terms of easily checkable graph topology conditions, is obtained for multi-agent systems with time-varying delays under switching topologies. Furthermore, numerical examples are presented to illustrate the obtained results, and the essential of some conditions and assumptions is verified for given switching communication topologies. [ABSTRACT FROM AUTHOR]

In this paper, the extremals of curvature energy actions on non-null regular curves in 2-dimensional de Sitter space are studied. We completely solve the Euler-Lagrange equation by quadratures. By using the Killing field, we construct three special coordinate systems and express the generalized elastica in 2-dimensional de Sitter space by integral explicitly. [ABSTRACT FROM AUTHOR]

Three-dimensional limit analysis for seismic stability of slopes with cracks is carried out within the framework of kinematic approach. Three types of failure mechanisms, i.e., the face failure, toe failure and base failure coupled with the most critical cracks are discussed. The sequence quadratic program, associated with a random trials algorithm is applied to search for the least upper bound results of the stability factor (critical height). A validation is carried out for the obtained results, using literature data and outputs from FLAC3D. The effects of slope width and seismic loads on the different failure mechanisms are discussed. Conclusion can be drawn that the width limitation mainly controls the slope failure mechanism. With respect to very narrow spaces, face failure is the most common among the considered failure mechanisms. With increasing seismic coefficient, some cracked slopes, which are prone to toe failure under static conditions, finally collapse dynamically in face failure or base failure mode. The increase in relative width or seismic coefficient will lead to the increasing of the volume of the failure soil mass. [ABSTRACT FROM AUTHOR]

We address stabilization problems of networked control systems in the presence of bounded packet losses and time-varying network-induced delays. When the delay is less than the transmission interval, we prove that the stability of the closed-loop system is implied by that of a switched system. Based on theories on switched systems, we present stabilizing conditions by using packet-loss-dependent Lyapunov functions, and design multiple controllers depending on the packet loss and the network-induced delay. Furthermore, based on the stabilizing conditions, we discuss the robustness of the stabilization against the packet loss and the network-induced delay. Several numerical examples and simulations are worked out to demonstrate the effectiveness of the proposed design approach. [ABSTRACT FROM AUTHOR]

We discuss a new consensus problem – a group consensus problem – in networks of dynamic agents. For a complex network consisting of several sub-networks owing to physical quantities or task distributions, it is concerned with this case that the agents in a sub-network share a consistent value while there is no agreement between any two sub-networks. When the information exchange is directed, a novel consensus protocol is designed to solve the group consensus problem. The convergence analysis is discussed and several criteria are established based on graph theories and matrix theories. Simulation results are presented to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Abstract: Crofton weed is an invasive alien plant which is causing significant economic and environmental losses in China. The purpose of this study is to evaluate the applicability of deoxy-liquefaction reaction to the utilization of Crofton weed. Deoxy-liquefaction experiments of two different sections (leaves and stems) and the whole plant of Crofton weed were performed at six different temperatures (375–500°C). Oils with low oxygen contents (<8wt%) and high HHVs (>40MJ/kg) were obtained. 425°C was the optimum temperature for obtaining oil from Crofton weed. Besides, solid chars with high HHVs of about 20MJ/kg were obtained. Gases with HHVs ranging from 1.6 to 5.7MJ/mol were produced. The overall energy recovery of the system was estimated at about 70%. [Copyright &y& Elsevier]

Abstract: Group consensus problems in networks of dynamic agents are addressed for two cases: (i) communication topologies are switching and the switching occurs among finite topologies arbitrarily; (ii) communication topologies are switching and the switching occurs among finite topologies arbitrarily, and there exist communication delays. We introduce double-tree-form transformations under which dynamic equations of agents are transformed into reduced-order systems. Based on the reduced-order systems, we obtain some analysis results for the two cases. In addition, we further investigate multi-group consensus as an extension of the group consensus, and present some analysis results by similar techniques. Simulation results are presented to demonstrate the effectiveness of the theoretical results. [Copyright &y& Elsevier]

We report a simple route to prepare silver nanoparticle (Ag NP) loaded amine functionalized poly-oligomeric (ethylene glycol) methyl ether methacrylate block poly-glycidyl methacrylate (POEGMA- b -PGMA) vesicles as an effective antibacterial agent. Self-assemblies of POEGMA- b -PGMA were prepared from reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization mediated by a POEGMA macro-chain transfer agent (macro-CTA) in ethanol. Amine-functionalized self-assemblies were applied for Ag NP loading by using amine and hydroxyl groups as both the coordination agent and reductant under hydrothermal condition in high-pressure steam sterilization. 12.7 wt.% content of fine Ag NP well-dispersed in vesicles showed excellent antibacterial activities with the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) below 5.0 and 10.0 mg/L against Escherichia coli and 2.5 and 80 mg/L against Staphylococcus aureus respectively. [ABSTRACT FROM AUTHOR]

Abstract: This paper studies the consensus problem of multiple agents with continuous-time first-order dynamics, where each agent can only obtain its states relative to its neighbors at sampling instants. It is assumed that the sampling period is different from the period of zero-order hold. Some sufficient and necessary conditions for consensus, which reveal the relationship among the interaction topology, controller gains, and the periods of sampler and zero-order hold, are provided. Moreover, the convergence rate is compared with that in the case when the period of zero-order hold is the same as the sampling period. Simulations are performed to validate the theoretical results. [Copyright &y& Elsevier]

Background. Platinum-based chemotherapy plays an antitumor role by damaging DNA. X-ray repair crosscomplementing protein 1 (XRCC1) participates in DNA repair and thus affects the sensitivity to platinum drugs. Two polymorphisms of XRCC1, rs25487 (Arg399Gln) and rs1799782 (Arg194Trp), have been widely studied for the association with clinical outcomes of platinum-based chemotherapy in Asian patients with non-small-cell lung cancer (NSCLC), but the results remain inconclusive. Thus, we performed the present meta-analysis. Methods. Literature search was performed in PubMed, Web of Science, and EMBASE up to June 2019. Odds ratios (ORs) for objective response ratio (ORR), Cox proportional hazard ratios (HRs) of overall survival (OS) and progression-free survival (PFS), and the corresponding 95% confidence intervals (95% CIs) were calculated to assess the association strengths between XRCC1 polymorphisms and clinical outcomes. Comparisons were performed in homozygous, heterozygous, dominant, and recessive models. Results. Finally, a total of 23 studies involving 5567 patients were included in the meta-analysis. Compared to ArgArg of rs25487, GlnGln (OR = 1.71 , 95% CI: 1.16-2.52, p =.007 , I 2 = 56.8 %) and GlnArg (OR = 1.23 , 95% CI: 1.07-1.40, p =.003 , I 2 = 29.0 %) were associated with higher ORR. Meanwhile, GlnGln indicated a favorable OS (HR = 0.60 , 95% CI: 0.40-0.88) and PFS (HR = 0.64 , 95% CI: 0.46-0.90). We also found positive associations between rs1799782 and ORR in all comparison models with low between-study heterogeneity. The association strength increased with the number of variant alleles (TrpTrp vs. ArgArg: OR = 1.73 , 95% CI:1.31-2.27; TrpArg vs. ArgArg: OR = 1.28 , 95% CI: 1.06-1.55), suggesting a gene dosage effect. In addition, TrpTrp predicted a longer OS. Conclusion. Our results showed that rs25487 and rs1799782 of XRCC1 are potential markers to predict clinical outcomes of platinum-based chemotherapy in Asian patients with NSCLC. [ABSTRACT FROM AUTHOR]

Railway intrusion detection is important for the safety of the railway operation. However, how to detect intruding events in the scene of unmanned aerial vehicle (UAV) surveillance is a challenging task, especially when there are multiple railway regions or unknown types of intruding objects. To tackle the above problems, a railway intrusion detection method is proposed for the scene of UAV surveillance. It can detect intruding events accurately without pre-setting the intruding object type by detecting the normal railway region and the abnormal railway region with intruding objects rather than recognizing the intruding objects directly. The proposed network consists of a novel Fused-convolutional long short-term memory (Fused-ConvLSTM) module for efficiently propagating spatial and temporal information; several attention modules for adaptively enhancing the feature information, such as the improved feature fusion layer; several lightweight strategies for reducing the computation complexity, such as lightweight feature extraction and width multiplier. Experiments are performed on the real aerial videos obtained by a micro UAV. The experimental results demonstrate that the proposed method can accurately detect railway intrusion events in aerial video, and effectively deal with the case of multiple railway regions and unknown intruding object types. The experimental results also demonstrate that the proposed network can achieve better performance than other object detection networks. • A novel deep learning-based railway intrusion detection method for UAV surveillance scenes is proposed without pre-setting the intruding object type. • A novel convolutional LSTM module called Fused-ConvLSTM is proposed. • An improved feature fusion layer is proposed. • An improved railway clearance intrusion detection network is proposed. • The experiments results based on real aerial videos demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This article studies the consensusability of multi‐agent systems with general linear continuous‐time dynamics. It is assumed that each agent can only obtain the information of other agents at sampling instants. Some sufficient and necessary conditions for consensusability in the case of state feedback are established, and it is shown that multi‐agent systems with periodic sampling are consensusable if and only if the system associated with each agent is stabilisable and the topology graph has a spanning tree. Furthermore, some methods are provided to seek controller gain and sampling period which ensure consensus. Simulations are performed to validate the theoretical results. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to investigate the influence of extractives on the yield and composition of oil obtained from biomass samples (Artemisia ordosica, corn stalk and wheat straw). Direct deoxy-liquefaction experiments of original and extracted biomass were performed at certain temperature in a stainless steel tubular reactor. Benzene–alcohol solvent extraction had significant effect on the product distribution of biomass, especially on the yield and composition of the product oils. The oil yield of original biomass and alkane content in the oil were in the range of 5.44–9.27% and 8.23–23.64%, while decreased to 3.83–4.45% and 1.07–6.03% for the extracted biomass. This study concludes that most of alkanes in the oil mainly derive from the decomposition of triglyceride and hydrocarbon existed in the extractives of biomass. The results might be helpful to study the origin of alkanes and benzene derivatives in the oil obtained from biomass via direct deoxy-liquefaction. [Copyright &y& Elsevier]

Colorectal cancer (CRC) is one of the most common solid tumors worldwide and has an extremely poor prognosis. MicroRNA-429 (miR-429) has been reported to participate in the progression of CRC. However, the pathological mechanisms require further investigation. The aim of the present study was to investigate the association between miR-429 and high mobility group box 3 (HMGB3) in CRC and the associated mechanism. The mRNA expression levels of miR-429 and HMGB3 in 65 paired CRC and adjacent tissues were examined by reverse transcription-quantitative PCR. Furthermore, a dual-luciferase reporter assay was performed to identify the association between miR-429 and HMGB3. Finally, the effects of miR-429 and HMGB3 on the proliferation and apoptosis of CRC cells were detected. As a result, it was identified that miR-429 expression was downregulated and HMGB3 expression was upregulated in CRC tissues compared with in adjacent non-cancer tissues, and the expression levels of miR-429 were negatively associated with those of HMGB3. Notably, HMGB3 was demonstrated to be a direct target of miR-429 by dual-luciferase reporter assay. Furthermore, transfection with a miR-429 mimic significantly inhibited HMGB3 expression and led to decreased proliferation and increased apoptosis of CRC cells. On the other hand, transient overexpression of HMGB3 partially inhibited the antitumor effects of miR-429. To the best of our knowledge, the present study demonstrated for the first time that miR-429 regulated the proliferation and apoptosis of CRC cells via HMGB3, suggesting a specific tumor suppressive function of the miR-429/HMGB3 signaling pathway in CRC. [ABSTRACT FROM AUTHOR]

Herein, a simple route to prepare porous microspheres with tuned pore structure and potential functionality based on epoxy functionalized block copolymers, poly hydroxypropyl methacrylate‐b‐ poly glycidyl methacrylate (PHPMA‐b‐PGMA), through a water‐in‐oil‐in‐water (W/O/W) double emulsion is reported. The effect of surfactant concentration and the composition of block copolymers are investigated. The solvent vapor swelling behavior of porous microspheres before and after cross‐linking is studied. It is interesting that after the swelling, the cross‐linked open pores are self‐healed to form closed pores, whereas the uncross‐linked ones are collapsed. It is believed that this observation will be useful in guest carrying and control release, and find its application in biomedical and pharmaceuticals. [ABSTRACT FROM AUTHOR]