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Contrast enhancement (CE) on brain non-contrast computed tomography (NCCT) is common after endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS), but its association with clinical outcomes is not well established. The current study aimed to investigate this relationship. We retrospectively reviewed consecutive patients with acute ischemic stroke who had hyperdensity on NCCT immediately after EVT for anterior circulation large vessel occlusion (LVO) from January 2016 to December 2019. We used ASPECTS combined with volume measurement by 3D reconstruction to estimate the extent and location of CE. Multivariable regression analysis was conducted to explore the risk factors associated with clinical outcome. In this study, 113 of 158 (71.52%) anterior circulation AIS-LVO patients had hyperdensity on brain NCCT. After strict inclusion and exclusion criteria, a total of 64 patients were enrolled in the final analysis. In logistic regression analysis, CE-ASPECTS, CE volume, CE at the caudate nucleus, M4 and M6 region were associated with 3-month poor functional outcome after adjusting for confounding factors. The conventional variable model was used for reference, including age, initial NIHSS, the procedure time, stent retriever passes, recanalization status and baseline ASPECTS, with AUC of 0.73. When combined with the above-named variables (conventional variables + CE-ASPECTS + CE volume + CE at caudate nucleus + CE at M4 region + CE at M6 region), the predictive power was significantly improved, with AUC of 0.87 (95% CI 0.78–0.95). The spatial location and volume of CE on NCCT obtained immediately after EVT were independent and strong predictors for poor outcome at 3-months in patients with AIS after excluding definite hemorrhage by 24-h follow up CT.

Suffering from fragile environment, poor accessibility and infrastructure, as well as social, political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional governance in China. By analyzing the spatial patterns and the influencing factors of the interprovincial mountain geographical names (IMGNs), the goal of this research is to clarify the geographical features of IMGNs and offer alternatives for the management of interprovincial mountain regions in China. The spatial visualization, the analysis of spatial agglomeration and the influencing factors of IMGNs were all implemented under a geographical information system. Results showed that there were 6869 IMGNs in China according to the database of “China’s Second National Survey of Geographical Names (2014–2018)”, including 4209 mountain geographical names, 1684 mountain peak geographical names and 976 the other mountain geographical names. Hunan Province had the largest number of names while Shanghai had the smallest number of names. In addition, the spatial variance of the mountain peak names and the mountain names were larger than that of the other mountain geographical names, and the IMGNs showed a significant clustering phenomenon in the southern part of China. The relative elevation and the population had an impact on the distribution of the IMGNs. The largest number of the names occurred where the relative elevation was between 1000–2000 m and where the population was between 40–50 million. Density of unnamed interprovincial mountain geographical entities declined from west to east in China. The analysis of generic names of different types of IMGNs implied that the naming of IMGNs is inconsistent. Based on these analyses, it is suggested that the government should take the IMGNs as management units, strengthen the naming of unnamed interprovincial mountain geographical entities, standardize the generic names of IMGNs and identify areas of poverty based on the survey of IMGNs.

n-Decane was chosen as a one-component surrogate fuel to investigate the combustion performance of Rocket Propellant-3(RP-3) aviation kerosene. Sensitivity analysis and the reaction-path analysis method were used to simplify the detailed reaction mechanism of n-decane, and a simplified mechanism including 36 species and 62 elementary reaction steps was obtained. Moreover, 38-step elementary reaction investigated in the reference was simulated in the paper. Numerical simulation method was conducted for both the 62-step and the 38-step reaction mechanisms using pre-evaporation combustion models. Simultaneously Bunsen burner for the combustion of premixed, pre-evaporated RP-3 aviation kerosene was designed to verify the simplified mechanism, and the temperature and gas component concentrations in the axial and radial directions at different heights were measured. The experimental results revealed that the reaction temperature and the CO2 concentration increased first and then decreased across the axial positions, but on the contrary for the O2 concentration. The temperature and the O2 concentration distributions of experimental results are in good agreement with that of numerical simulation results for the 62-step simplified reactions, and the CO2 concentration distribution is in general agreement with the numerical data. But the 38-step simplified reactions can only predict the change trend for the important parameters which are mentioned above. Through the contrastive analysis for these two kinds of simplified reactions, the 62-step reactions can more accurately simulate the combustion characteristics of RP-3 kerosene. And n-decane can be used as a one-component surrogate fuel for RP-3 aviation kerosene.

Background and aims Intrahepatic cholangiocarcinoma (ICC) is an aggressive tumor with a high fatality rate. It was recently found that parathyroid hormone-like hormone (PTHLH) was frequently overexpressed in ICC compared with non-tumor tissue. This study aimed to elucidate the underlying mechanisms of PTHLH in ICC development. Methods The CCK-8 assay, colony formation assays, flow cytometry and a xenograft model were used to examine the role of PTHLH in ICC cells proliferation. Immunohistochemistry (IHC) and western blot assays were used to detect target proteins. Luciferase reporter, chromatin immunoprecipitation (ChIP) and DNA pull-down assays were used to verify the transcription regulation of activating transcription factor-2 (ATF2). Results PTHLH was significantly upregulated in ICC compared with adjacent and normal tissues. Upregulation of PTHLH indicated a poor pathological differentiation and intrahepatic metastasis. Functional study demonstrated that PTHLH silencing markedly suppressed ICC cells growth, while specific overexpression of PTHLH has the opposite effect. Mechanistically, secreted PTHLH could promote ICC cell growth by activating extracellular signal-related kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathways, and subsequently upregulated ATF2 and cyclinD1 expression. Further study found that the promoter activity of PTHLH were negatively regulated by ATF2, indicating that a negative feedback loop exists. Conclusions Our findings demonstrated that the ICC-secreted PTHLH plays a characteristic growth-promoting role through activating the canonical ERK/JNK-ATF2-cyclinD1 signaling pathways in ICC development. We identified a negative feedback loop formed by ATF2 and PTHLH. In this study, we explored the therapeutic implication for ICC patients. Electronic supplementary material The online version of this article (10.1186/s12967-017-1342-1) contains supplementary material, which is available to authorized users.

A kind of hollow vortex Gaussian beam is introduced. Based on the Collins integral, an analytical propagation formula of a hollow vortex Gaussian beam through a paraxial ABCD optical system is derived. Due to the special distribution of the optical field, which is caused by the initial vortex phase, the dark region of a hollow vortex Gaussian beam will not disappear upon propagation. The analytical expressions for the beam propagation factor, the kurtosis parameter, and the orbital angular momentum density of a hollow vortex Gaussian beam passing through a paraxial ABCD optical system are also derived, respectively. The beam propagation factor is determined by the beam order and the topological charge. The kurtosis parameter and the orbital angular momentum density depend on beam order n, topological charge m, parameter γ, and transfer matrix elements A and D. As a numerical example, the propagation properties of a hollow vortex Gaussian beam in free space are demonstrated. The hollow vortex Gaussian beam has eminent propagation stability and has crucial application prospects in optical micromanipulation.

To deliver drug locally and relieve the syndrome of pain after uterine artery embolization, N-[tris (hydroxymethyl) methyl] acrylamide-gelatin microspheres were prepared based on inverse suspension polymerization and then separated into a number of subgroups (150-350, 350-560, 560-710, 710-1,000, and 1,000-1,430 μm) by wet-sieving. The microspheres were dried by lyophilization or by washing with anhydrous ethanol. And ketoprofen was loaded by soaking dried blank microspheres into concentrated ketoprofen ethanol solution. The ketoprofen loading level in different subgroups of microspheres was measured and found higher when the microspheres were dried by lyophilization. Equilibrium water content and mean diameters of microspheres decreased after drug loading, especially in subgroups with larger size. The microspheres went through the catheter without any difficulty. Compression and relaxation tests were performed on microspheres before lyophilization, embosphere™, microspheres after lyophilization and ketoprofen loading microspheres. The Young's moduli were 54.74, 64.19, 98.15, and 120.44 kPa, respectively. The release of ketoprofen from microspheres in different subgroups was studied by using the USPII method and T-cell apparatus, respectively. The results indicate that the release rate of ketoprofen depends upon the diameter of microspheres, the type of dissolution apparatus and the flow rate of media in the case that T-cell apparatus was applied. The CH50 test shows that the activation of complement by ketoprofen-loaded microspheres was lower than by blank ones.

Utilizing the extended projective Ricatti equation expansion method, abundant variable separation solutions of the (2+1)-dimensional dispersive long wave systems are obtained. From the special variable separation solution (38) and by selecting appropriate functions, new types of interaction between the multi-valued and the single-valued solitons, such as semi-foldon and dromion, semi-foldon and peakon, semi-foldon and compacton are found. Meanwhile, we conclude that the solution v is essentially equivalent to the ’universal” formula (1).

An extended mapping approach is used to obtain a new type of variable separation excitation, with three arbitrary functions, of the 2+1-dimensional generalized dispersive long wave equation (DLWE). By selecting appropriate functions, the richness of nonpropagating solitons, such as nonpropagating dromion, nonpropagating ring, nonpropagating lump, and nonpropagating foldon, etc., is displayed for the ($2+1$)-dimensional generalized dispersive long wave equation (DLWE) in this paper. Meanwhile, we conclude that the solution v1 and v2 are essentially equivalent to the “universal” formula.