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The association between imaging features closely associated with symptomatic intracranial atherosclerotic plaques and early-onset post-stroke depression (PSD) is currently unclear.76 ischemic stroke patients who underwent high-resolution vessel wall magnetic resonance imaging (HR-VWI) were divided into PSD and non-PSD groups according to their DSM-V diagnoses and HAMD-17 scores at 14 days after onset. Clinical data and the imaging features associated with symptomatic plaques (including the enhancement index (EI), remodeling index, and plaque surface irregularity) were compared between groups. Multifactorial logistic regression analysis was used to find independent predictors of early-onset PSD. Spearman rank correlation analysis explores the association between clinical data, symptomatic plaque imaging features, and HAMD-17 in patients.The sample comprised 36 patients with early-onset PSD. The symptomatic plaque EI and infarct volume were significantly higher in depressed patients than in patients without depression (P 0.05). Multivariate logistic regression showed that symptomatic plaque EI could be used as an independent predictor of early-onset PSD after correcting for the confounding factor of infarct volume (OR = 1.034, 95% CI:1.014-1.055, P = 0.001). In the total sample, symptomatic plaque EI, infarct volume, and HAMD-17 had a significant positive correlation with each other (P 0.05).This study focused only on the patients' symptomatic plaques and did not monitor patients' systemic inflammation levels at the time of HR-VWI.The degree of symptomatic plaque enhancement is an independent predictive imaging marker of early-onset PSD and can be used the early diagnosis of early-onset PSD.

A stochastic compartmental model for cholera is investigated, which incorporates the effect of two transmission pathways on the diseases via contaminated water. Multiple stages of infection and multiple states of pathogen and environmental white noises are considered, which include or extend the cholera models in some existing articles. The existence of a unique stationary distribution and ergodicity of the model are obtained by using a suitable Lyapunov function, which determines a critical value R 0 * corresponding to a basic reproduction number R0 of the ordinary differential equation. The results mean if R 0 * > 1 , the system still retains the stability and all individuals are persistent in a long term. In addition, the sufficient conditions for extinction of diseases are derived. What’s more, we provide a new method in constructing a Lyapunov function, which can be successfully applied to other complex high-dimensional systems.

This paper performs optimization-based controller design to avoid control interaction among multiple converter-interfaced generators (CIGs). To assess the control interaction between CIGs, an impedance-based stability analysis. Unexpected instability resulting from the CIG disconnection is investigated in a test case where three CIGs are connected to a microgrid. Parameter sensitivity is performed to determine which control parameter has more influence on the stability, and particle swarm optimization is utilized to adjust the control parameters to enhance the stability with computational efficiency. Simulation results demonstrated that the proposed tuning procedure helps ensure the stability of the test case even if a CIG is disconnected from the grid.

Epoxy asphalt composites (EACs) have been recommended to be a prior choice to obtain long-life pavements. However, the present anhydrides-cured EACs have to be field-maintained in high summer for over 45 days to achieve their ultimate performance. To be opened to traffic immediately, sealed accelerants, triggered by the compact pressure when paved, were employed to accelerate post-cure of EACs. Compared with microcapsules complicatedly synthesized by interfacial polymerization, sealed macroporous-resins containing accelerants, which was simply prepared by covering accelerant-soaked macroporous-resins with polytetrafluoroethylene (PTFE), made it possible to be opened to traffic quickly. It is attributed to the bigger capsule sizes and higher encapsulation efficiencies for them to be easier crushed by aggregates and encapsulate enough accelerants to be released when compacted. This paper reports the facile, low-cost and scalable approach to make anhydrides-cured EACs open to traffic quickly which facilitates EACs to be ideal long-life paving materials.

Epoxy asphalt binder is a completely different thermosetting paving material from traditional modified asphalt binders. To character its properties, standard test method of tensile properties for plastics is borrowed. However, the correlations within tensile properties and road-paving properties like i.e. temperature stability and durability are not clear. In this paper, dynamic shear rheometer (DSR) was used to test its rheological performances in comparison of base asphalt binder and SBS modified asphalt binder. Fluorescence microscope was used to trace the microscope structure evolution process, and Scanning Electron Microscope (SEM) to observe the fracture profile of epoxy asphalt at −40 °C. Results indicate that creep strains of epoxy asphalt are 10 −7 to 10 −2 times as much as that of base asphalt, and 10 −6 to 10 −2 times of Styrene–Butadiene–Styrene (SBS) modified asphalt. Creep and recovery experiments find that epoxy asphalt is completely elastic after 100 loading–unloading circles, which implies that epoxy asphalt has a remarkable anti-rutting potential, on the contrary, base asphalt binder and SBS modified asphalt binder are in the state of Newton liquids under the same experimental conditions. Temperature sweep by DSR shows that epoxy asphalt has a superior thermal stability from −30 °C to 120 °C, which is verified by the two transition peaks at −22 °C and 28 °C obtained from dynamic mechanical thermal analyzer (DMTA). High performances of epoxy asphalt binder are attributed to crosslinked bimodal networks during thermal cure which were observed by fluorescence microscope. These experiments qualify the excellent properties of epoxy asphalt binder from the viewpoint of rheology, and the consistency within the rheological tests verify the feasibility of using temperature sweep to character the temperature stability of epoxy asphalt binder.

We review the abstract concept of a ‘state’ – an internal representation posited by reinforcement learning theories to be used by an agent, whether animal, human or artificial, to summarize the features of the external and internal environment that are relevant for future behavior on a particular task. Armed with this summary representation, an agent can make decisions and perform actions to interact effectively with the world. Here, we review recent findings from the neurobiological and behavioral literature to ask: ‘what is a state?’ with respect to the internal representations that organize learning and decision making across a range of tasks. We find that state representations include information beyond a straightforward summary of the immediate cues in the environment, providing timing or contextual information from the recent or more distant past, which allows these additional factors to influence decision making and other goal-directed behaviors in complex and perhaps unexpected ways.