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Background: There is increasing evidence on the prognostic significance of D-dimer and fibrinolysis in stroke. However, the systematic analysis of their relationship with adverse outcomes after stroke is lacking. Herein, we comprehensively assessed the correlation of D-dimer and fibrinolysis with stroke outcomes through meta-analysis. Methods: Studies for systematic literature review were retrieved from PubMed, EMBASE, and Cochrane Library databases. The association of D-dimer and fibrinolysis with outcomes of stroke patients was expressed as an odds ratio (OR) with 95% confidence intervals (95% CI). Results: Totally, 52 studies comprising 21,473 stroke patients were included. The results showed that the high D-dimer level was significantly associated with peripheral venous thrombosis after stroke (OR 1.03, 95% CI 1.01–1.05), poor outcome (MRS >2) after stroke (OR 1.731, 95% CI 1.464–2.048), death after stroke (OR 2.367, 95% CI 1.737–3.224), stroke recurrence (OR 1.229, 95% CI 1.113–1.358), and early neurologic deterioration (NIHSS >4) (OR 1.791, 95% CI 1.117–2.870). Moreover, high fibrinogen level was significantly associated with poor outcome (MRS >2) after stroke (OR 1.650, 95% CI 1.314–2.071), death after stroke (OR 1.310, 95% CI 1.128–1.520), stroke recurrence (OR 1.228, 95% CI 1.166–1.422), early neurologic deterioration (NIHSS >4) (OR 2.381, 95% CI 1.156–4.904), and coronary events after stroke (OR 1.427, 95% CI 1.232–1.653). Conclusion: Fibrinogen and D-dimer may be associated with adverse outcomes in patients with stroke, suggesting that they may serve as possible biomarkers for post-stroke adverse outcomes.

Purpose: To investigate the neuroprotective effect of erythropoietin (EPO) against hypoxic-ischemic brain injury in neonatal mice, and the underlying mechanism(s) of action. Methods: Sixty neonatal mice were assigned to 3 groups: sham, model and EPO intervention groups, each with 20 mice. Western blot assay was used to determine changes in the protein expressions of AMPK, UCP2 and KLF2. Fluorescence intensity of reactive oxygen species (ROS) was evaluated with flow cytometry. Results: The protein expressions of AMPK and KLF2 in the cerebral tissues of EPO intervention mice were significantly up-regulated, relative to model mice (p < 0.05), while UCP2 protein level was also significantly higher in EPO intervention mice than in model mice (p < 0.05). Mean fluorescence intensity of ROS was significantly higher in the cerebral cortex of model mice than in sham mice, but it was down-regulated in the cerebral cortex of mice in EPO intervention group, relative to the model group (p < 0.05). Conclusion: EPO exerts neuroprotective effect by activating AMPK pathway, up-regulating protein expression of UCP2, inhibiting production of mitochondrial ROS, and reducing oxidative stress in brain tissue. Thus, EPO has potentials for use in clinical practice as a neuroprotective agent.

The role transition of poly(N-isopropylacrylamide) ionic microgels (PNI microgels) in dispersion polymerization by changing the monomer type was investigated in this work. Firstly, PNI microgels with different diameters were prepared by precipitation polymerization. Then they were respectively employed to the dispersion polymerization of glycidyl methacrylate (GMA) and styrene (St) in methanol. Finally, poly(glycidyl methacrylate) (PGMA) and polystyrene (PS) nanoparticles were obtained. The morphology, thermo-sensitivity and element analysis of PNI microgels and these polymer nanoparticles were characterized. It indicated that GMA polymerized inside the microgels while the polymerization of St occurred outside the microgels. This phenomenon demonstrated that the PNI microgels acted as seed for the polymerization of GMA while turned into particulate stabilizer for the polymerization of St. The mechanism of the role transition of PNI microgels from seed to particulate stabilizer was discussed. It revealed that compatibility and chemical interaction between PNI microgels and monomers contributed a lot to this role transition.

Preparation of small size core-shell polymer nanoparticles has significant applications in photonic crystal materials and drug delivery systems. Although core-shell nanoparticles could be easily prepared by seeded emulsion polymerization, their size was generally larger than that of seeds, which limited their further applications in some areas. In this work, a new method was utilized to prepare small size core-shell polymer nanoparticles. In detail, poly(N-isopropylacrylamide) ionic microgels (encoded as PNI microgels) with controllable diameter were firstly prepared and then used as seeds in seeded emulsion polymerization of styrene. After polymerization, core-shell nanoparticles which were smaller in size than that of seeds were obtained. In order to reveal this abnormal phenomenon, the inner structure, components, element distribution, thermo-sensitivity and deformability of the obtained nanoparticles were characterized by TEM, FTIR, DSC, EDS, DLS and AFM. It was found that the core composed of polystyrene and the shell composed of PNI microgels in the core-shell nanoparticles. The detailed formation process was then studied systematically. It was found that polystyrene nanoparticles formed within PNI microgels and peeled off from the seeds when they were large enough. Considering the weak ionic interaction of PNI microgels, mechanism for this phenomenon was proposed. Factors, such as initiator type, microgel type, cross-linking degree and stirring speed, also had significant effects on the formation of core-shell nanoparticles.

BIER (Bit Index Explicit Replication) is a novel solution for multicast. Although it has not been applied to real network, without establishing a multicast tree and maintaining per-flow state, BIER has obvious advantages over existing multicast tree-based routing solution. However, we found data redundancy in large-scale network when BIER domain has more than one SDs (Sub Domains) or SIs (Set Ids). In fact, some of them can be decreased. This paper proposed HF-BIER (Hierarchical Forwarding Bit Index Explicit Replication) model which is able to decrease the data redundancy. In order to add multicast control information, we set up Transfer BFR and LL (Logical Level) in HF-BIER model. This paper describes the forwarding mechanism of HF-BIER, and figures out the workflow of control plane and data plane of HF-BIER. Finally, simulation has been made to prove HF-BIER can effectively reduce the forwarding redundancy in the core network and critical links.

As a new environmentally friendly liquid dielectric material, vegetable insulating oil has been used in oil-filled transformers more and more widely. In transformers, ageing, overheating faults, and discharge faults cause the decomposition of insulating oil and insulating paper, and then cause dissolved gases in the oil. These transformer fault diagnosis and prediction can be realized by Dissolved Gas-in-oil Analysis (DGA) method, which is closely related to the diffusion process of gas in oil. However, few research involves diffusion processes of dissolved gases and thus no effective DGA method for vegetable insulating oil-filled transformers has been proposed. In this paper, in order to have a better understanding for vegetable oil transformer fault process and improve the effective of DGA method as theoretic support for vegetable oil transformers, the research of diffusion properties and mechanism of characteristic gases in camellia insulating oil is very meaningful. The molecular dynamics simulation based on polymer consistent force field (PCFF) was adopted to analyze diffusion processes of characteristic gases. Impacts of gas species as well as temperatures for molecular diffusion coefficients were studied. The result provides theoretic support for fault condition assessment and operating maintenance of vegetable insulating oil-filled transformers, and also has great theoretical reference value for ensuring safe operation of vegetable insulating oil-filled transformers.