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Biomass‐derived carbon (BC) has attracted extensive attention as anode material for lithium ion batteries (LiBs) due to its natural hierarchical porous structure and rich heteroatoms that can adsorb Li+. However, the specific surface area of pure biomass carbon is generally small, so we can help NH3 and inorganic acid produced by urea decomposition to strip biomass, improve its specific surface area and enrich nitrogen elements. The nitrogen‐rich graphite flake obtained by the above treatment of hemp is named NGF. The product that has a high nitrogen content of 10.12% has a high specific surface area of 1151.1 m2 g−1. In the lithium ion battery test, the capacity of NGF is 806.6 mAh g−1 at 30 mA g−1, which is twice than that of BC. NGF also showed excellent performance that is 429.2 mAh g−1 under high current testing at 2000 mA g−1. The reaction process kinetics is analyzed and we found that the outstanding rate performance is attributed to the large‐scale capacitance control. In addition, the results of the constant current intermittent titration test indicate that the diffusion coefficient of NGF is greater than that of BC. This work proposes a simple method of nitrogen‐rich activated carbon, which has a significantly commercial prospect. [ABSTRACT FROM AUTHOR]

Objective To establish a platform by using carotid MRI and computational fluid dynamics (CFD) to assess hemodynamic changes around carotid atherosclerotic plaques. Methods Thirteen patients with carotid atherosclerosis were recruited in this study. Six volunteers were regarded as normal controls. All the patients and volunteers underwent carotid MRI and contrast-enhanced magnetic resonance angiography (CEMRA). Carotid MRI was used to visualize the plaque structures and components. All plaques were divided into different types according to plaque components. CEMRA images were used to obtain three-dimensional (3D) models of carotid bifurcations, whose boundary conditions were specified using CFD front-end software, and then the mesh file of the 3D models were obtained to import to CFD software to visualize hemodynamic maps, including wall shear stress (WSS), static pressure and blood velocity. Results Fifteen diseased internal carotid arteries (ICAs) were assessed. According to the MRI appearance of the plaques, the types of these plaques were from IV-V to VIII. All of these were vulnerable plaques which caused irregular stenosis of ICAs. The WSS, static pressure and blood velocity were (79.86 ± 57.83) Pa, (- 7586.81 ± 9313.83) Pa, (2.76±1.81) m/s, respectively in the diseased ICAs group and (2.52 ± 0.58) Pa, (- 71.65 ± 30.89) Pa, (0.21 ± 0.06) m/s, respectively in the normal control group. In the diseased ICAs group WSS was elevated heterogenously and static pressure was decreased heterogenously near the plaques. The blood velocity near the plaques was increased but still streamlined. Statistical significant differences were shown for WSS, static pressure and blood velocity between 2 groups (P = 0.000, for all). Conclusions The platform combining MRI and CFD can be used to analyze the plaque structures and fluid dynamic change near the plaques, suggesting hemodynamics plays an important role in the plaque progression and vulnerability. [ABSTRACT FROM AUTHOR]

Computed tomography perfusion (CTP) map can sensitively and accurately distinguish between infarct core and ischemic penumbra. However, CTP mapping software might not generate a perfusion map because of head movement; thus, analysing CTP source images (CTP-SI) is necessary in this situation to provide information for stroke diagnosis and therapy. In our work, 'one-stop shop' computed tomography (CT) examination including non-contrast-enhanced CT (NCCT), CTP, CT angiography (CTA) were performed in 24 patients with symptoms of acute stroke less than 9 hours. We divided patients into two groups (with and without delayed perfusion on CTP-SI), and compared the Alberta Stroke Program Early CT Score (ASPECTS) on CTP-SI and CTA-SI with follow-up imaging. Using follow-up imaging ASPECTS as the final infarct size, our results suggests that the ASPECTS of both CTP-SI and CTA-SI effectively predict final infarct core in the group without delayed perfusion, whereas CTP-SI has a potential advantage over CTA-SI in being able to predict final infarct core in the group with delayed perfusion. In conclusion, CTP-SI provides useful complementary information when CTP map software could not generate perfusion maps. [ABSTRACT FROM AUTHOR]