The hot deformation behavior and microstructure evolution of AlCrFe2Ni2(MoNb)0.2 eutectic high entropy alloy at deformation temperatures of 900 °C–1100 °C and strain rates of 0.001 s−1∼1 s−1 were ...systematically investigated by hot compression tests. The principal structure equations of AlCrFe2Ni2(MoNb)0.2 high entropy alloy were constructed using the Arrhenius equation modified by Zener-Hollomon parameters. The decrease of strain rate and the increase of deformation temperature can enhance the continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) processes simultaneously. The power dissipation and instability diagrams were constructed according to the power dissipation theory and instability criterion, and the hot processing diagrams with strains of 0.3–0.6 were obtained by combining with the Dynamic Material Model (DMM) theory. According to the analysis of power dissipation rate and processing safety zone, the optimal hot processing parameters were found to be ε = 0.6 for the true strain, T = 1050–1100 °C, ε˙ = 0.0037–0.031 s−1.
The milk fat globule membrane (MFGM) is a complex structure with numerous functions, and its composition is affected by many factors. There have been few systematic investigations on goat MFGM ...proteome profiling during lactation. Individual milk samples from 15 healthy dairy goats were obtained at six lactation time points for investigation of the MFGM proteome using both data-independent acquisition (DIA) and data-dependent acquisition (DDA) proteomics techniques combined with multivariate statistical analysis. Using the DIA method, 890 variably abundant MFGM proteins were discovered throughout the lactation cycle. From 1 to 240 d, butyrophilin subfamily 1 member A1, lipoprotein lipase, perilipin-2, and adipose triglyceride lipase were upregulated, while APOE, complement C3, clusterin, and IgG were downregulated. Furthermore, from 1 to 90 d, annexin A1, annexin A2, and antithrombin-III were downregulated, then upregulated by d 240. Albumin had a high degree of connectedness, indicating that it was a key protein, according to protein–protein interaction research. Overall, our findings gave new insights into the biological features of MFGM protein in goat milk throughout lactation, which may aid in the creation of specialized MFGM products and infant formula.
Purpose
Intravoxel incoherent motion is a diffusion-weighted imaging magnetic resonance imaging technique that measures microvascular perfusion from a multi-b value sequence. Intravoxel incoherent ...motion microvascular perfusion has not been directly compared to conventional dynamic susceptibility contrast perfusion-weighted imaging in the context of acute ischemic stroke. We determined the degree of correlation between perfusion-weighted imaging and intravoxel incoherent motion parameter maps in patients with acute ischemic stroke.
Methods
We performed a retrospective cohort study of acute ischemic stroke patients undergoing thrombectomy treatment triage by magnetic resonance imaging. Intravoxel incoherent motion perfusion fraction maps were derived using two-step voxel-by-voxel post-processing. Ischemic core, penumbra, non-ischemia, and contralateral hemisphere were delineated based upon diffusion-weighted imaging and perfusion-weighted imaging using a Tmax >6 s threshold. Signal intensity within different brain compartments were measured on intravoxel incoherent motion (IVIM f, IVIM D*, IVIM fD*) parametric maps and compared the differences using one-way ANOVA. Ischemic volumes were measured on perfusion-weighted imaging and intravoxel incoherent motion parametric maps. Bland–Altman analysis and voxel-based volumetric comparison were used to determine the agreements among ischemic volumes of perfusion-weighted imaging and intravoxel incoherent motion perfusion parameters. Inter-rater reliability on intravoxel incoherent motion maps was also assessed. Significance level was set at α < 0.05.
Results
Twenty patients (11 males, 55%; mean age 67.1 ± 13.8 years) were included. Vessel occlusions involved the internal carotid artery (6 patients, 30%) and M1 segment of the middle cerebral artery (14, 70%). Mean pre-treatment core infarct volume was 19.07 ± 23.56 ml. Mean pre-treatment ischemic volumes on perfusion-weighted imaging were 10.90 ± 13.33 ml (CBV), 24.83 ± 23.08 ml (CBF), 58.87 ± 37.85 ml (MTT), and 47.53 ± 26.78 ml (Tmax). Mean pre-treatment ischemic volumes on corresponding IVIM parameters were 23.20 ± 25.63 ml (IVIM f), 14.01 ± 16.81 ml (IVIM D*), and 27.41 ± 40.01 ml (IVIM fD*). IVIM f, D, and fD* demonstrated significant differences (P < 0.001). The best agreement in term of ischemic volumes and voxel-based overlap was between IVIM fD* and CBF with mean volume difference of 0.5 ml and mean dice similarity coefficient (DSC) of 0.630 ± 0.136.
Conclusion
There are moderate differences in brain perfusion assessment between intravoxel incoherent motion and perfusion-weighted imaging parametric maps, and IVIM fD* and perfusion-weighted imaging CBF show excellent agreement. Intravoxel incoherent motion is promising for cerebral perfusion assessment in acute ischemic stroke patients.
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• The highly branched sulfonated poly(ether ether ketone)s were synthesized. • The highly branched sulfonated polymer/antioxidant composites were prepared. • The membranes exhibited ...excellent oxidative stability and proton conductivity.
The branched sulfonated poly(ether ether ketone)s, derived from bisphenol fluorene, 1,1,1-tris(4-hydroxyphenyl)ethane, sulfonated difluorobenzophenone and 4,4′-difluorobenzophenone, were synthesized by potassium carbonate mediated nucleophilic polycondensation reaction. The highly branched sulfonated polymer/antioxidant composites were prepared using antioxidant 1010 as a functional additive in order to further improve the properties of the polymer. The composites were soluble in the polar organic solvents, such as NMP, DMAc, DMSO and DMF, and could be readily cast to form tough and smooth films. The membranes exhibited excellent oxidative stability, good proton conductivity and thermal stability. The maximum oxidative stability of the membranes with 5
wt% antioxidant was about 1.5 times larger than that of the sample without the antioxidant. The results showed that adding the antioxidant was an effective way to improve oxidative stability of the membranes.
Background:
Early hematoma expansion (HE) occurs in patients with intracerebral hemorrhage (ICH) within the first few hours from ICH onset. Hematoma expansion has been considered as an independent ...predictor of poor clinical outcome and mortality after ICH. Island sign (IS) on the non-contrast computed tomography (NCCT) appears to increase the rate of detection of HE. However, there is insufficient evidence to declare that IS is an independent predictor for ICH patients prognosis and classification.
Objectives:
To investigate whether IS on NCCT could predict HE and functional outcome following ICH.
Methods:
Major databases were systematically searched, including PubMed, EMBASE, Cochrane library, and the Chinese database (CNKI, VIP, and Wanfang databases). Studies about the associations between IS and HE or IS and clinical outcome were included. The pooled result used the odds ratio (OR) with a 95% confidence interval (CI) as effect size. Heterogeneity and publication bias were assessed. Subgroup analysis and meta-regression were applied to detect potential factors of heterogeneity.
Results:
Eleven studies with 4,310 patients were included in the final analysis. The average incidence rate of IS and HE were 21.58 and 33%, respectively. The ideal timing for assessing HE was also not uniform or standardized. We separately performed two meta-analyses. First, 10 studies were included to estimate the association between IS and HE. The pooled OR was statistically significant (
OR
= 7.61, 95% CI = 3.10–18.67,
P
< 0.001). Second, four studies were included in the meta-analysis, and the pooled result showed that IS had a significantly positive relationship with poor outcome (
OR
= 3.83, 95% CI = 2.51–5.85,
P
< 0.001).
Conclusions:
This meta-analysis showed that NCCT IS is of great importance and value for evaluation of HE and poor outcome in patients with ICH. Future studies should focus on developing consensus guidelines, and more studies with large sample size and longitudinal design are needed to validate the conclusions.
The AlCrFe2Ni2(MoNb)x multiphase high entropy alloys were designed, prepared and characterized. The synergistic effect of Mo and Nb alloying on microstructures and mechanical properties of ...AlCrFe2Ni2-based high entropy alloy were investigated. By synergistic alloying with Mo and Nb, the volume fraction of the BCC phase increased, and a novel Laves phase with hexagonal close-packed(HCP) structure was formed. With the increase of Mo and Nb content, the alloys dramatically transformed from equiaxed grain with multiple phases to dendrites with the spinodal decomposition structure of the A2 phase and B2 phase, as well as inter-dendrites with the eutectic structure of the FCC phase and Laves phase. Furthermore, the solidification behavior of the alloys varied considerably as the increase of Mo and Nb content. The coexisting solidification microstructure of the eutectic structure and spinodal decomposition structure in the AlCrFe2Ni2(MoNb)0.3, AlCrFe2Ni2(MoNb)0.5 and AlCrFe2Ni2(MoNb)0.7 alloys have hardly been observed in other HEAs. The increase of Mo and Nb elements tends to segregate in the front of the liquid–solid interface, which hinders the growth of the FCC phase and leads to the formation of fine rod-like morphology. The synergistic effect of the fine grain strengthening and the solid solution strengthening resulted in high yield strength and fracture strength of 878 MPa and 2830 MPa, maintaining high plastic strain of 43.7%. Further increasing the content of Mo and Nb would lead to the increase of brittle Laves phase, with the second phase strengthening becoming the dominant strengthening mechanism, resulting in an increase in yield strength to 1549 MPa and a decrease in plastic strain to 8.6%. The investigation results would provide a guide for strengthening the macroscopic mechanical properties of eutectic high entropy alloys through synergistic alloying effect.
This study focuses on the generation of the bubble-free layer during the fabrication of the metal foam using the direct melt foaming method. The theoretical models for the three stages during the ...foaming process have been established, and the boundary conditions have been discussed. The results from the theoretical study indicated that the bubble number of the liquid foam played a critical role in the generation of the bubble-free layer, thus, improving the bubble number retards the velocity of the bubble-free layer generation. The liquid film rupture led to the expansion of the local cross-sectional area of the Plateau border channel and increased the drainage velocity, thus, resulting in an enhancement in the bubble-free layer. Additionally, the verification experiments were conducted by employing the graphene nanoflakes (GNFs) as the heterogeneous nucleation agent. The findings indicated that the generation of the bubble-free layer was hindered, and the bubble-free layer was altogether absent in case the content of the heterogeneous nucleation agent was enhanced.
The study aims to determine whether volume transfer constant (K(trans)) maps calculated from first-pass perfusion computed tomographic data are a biomarker of cerebral collateral circulation and ...predict the clinical outcome in acute ischemic stroke caused by proximal arterial occlusion.
Consecutive patients with acute occlusion of the middle cerebral artery who received endovascular treatment were enrolled. Digital subtraction angiography, computed tomographic angiography with maximum intensity projection, and K(trans) maps were used to assess their collateral circulation. Agreement between different methods was evaluated using the χ(2) tests. The correlations of various radiological and clinical outcomes with the collateral flow score, as determined from K(trans) maps, were calculated.
Seventy-five patients were included, comprising 39 women and 36 men, with a mean age of 65.3±14.6 years. Collateral flow score on K(trans) maps had the highest correlation with digital subtraction angiography (κ=0.8101; P=0.9796). Twenty-five patients had poor collateral circulation on K(trans) maps, 25 had intermediate collateral flow, 20 had good collateral flow, and 5 had excellent collateral flow. Better collateral circulation was associated with better clinical outcome (P<0.0001).
K(trans) maps extracted from standard first-pass perfusion computed tomography are correlated with collateral circulation status after acute proximal arterial occlusion and predictive of outcome.
This work proposes a new morphological random walker (MRW) method for hyperspectral anomaly detection. The proposed method introduces a morphology-based objective function into a random walker (RW) ...algorithm, sufficiently exploiting spatial morphological property and spatial similarity of HSIs for detection. The MRW method comprises two major stages. Firstly, we employ the extended morphological profiles (EMPs) and different operations to extract the spatial morphological property of HSIs. Second, according to the morphological property, we construct a morphology-based objective function. This function is incorporated into the RW-based optimization model, encoding the spatial similarity of HSIs in a weighted graph. Two factors determine the class of test pixels, including the spatial morphological information learned by EMPs, and the spatial correlation among adjoining pixels modeled by the weighted graph. Since the two factors are well considered in the MRW method, the proposed method illustrates outstanding detection performances for several widely used real HSIs.
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