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A series of negative temperature coefficient (NTC) thick-film ceramics based on Co2.77Mn1.71Fe1.10Zn0.42O8 (CMFZ) were successful prepared using a slurry spin coating technique. The high density and stable B25/50 constant in the range of 3829–3862 K of CMFZ thick films were obtained. The feasibility of preparing CMFZ thick films by spin coating is proved. It is confirmed that the microstructure and electrical properties of films are sensitive to the solid content in pastes. A smoother and denser surface morphology and relatively high electrical stability is obtained in 70 wt% solid content with the resistance drift rate of 19.4%. The resistance drift rate of all samples is found to be less than 1% per 100 h after pre-aging at 125 °C for 400 h. Compared to the traditional screen-printing method, spin coating simplifies the process steps and reduces some variables that could affect the quality of the thick film. These results clearly indicate that the spin coating technique is a potential and competitive method in the production of NTC thick film ceramic.

A 31-year-old man with Duchenne muscular dystrophy was admitted to our center, having infarctions in bilateral cerebral hemispheres and an occluded right middle cerebral artery. His right middle cerebral artery was spontaneous recanalization on the next day, and thrombus in the left ventricle vanished on the eighth day after giving warfarin.

In this study, we investigated the Cr(VI) uptake mechanism of planktonic cells and biofilms of Bacillus subtilis (B. subtilis) ATCC-6633. Data showed that the effect of planktonic cells on the Cr(VI) uptake was quite different from that of biofilms. Planktonic cells had strong ability of Cr(VI) reduction, while biofilms possessed a great potential of Cr(III) immobilization. For planktonic cells, 100 mg/L Cr(VI) could be completely reduced. Both exopolymeric substances and cytoplasmic extracts contributed to high capacity of Cr(VI) reduction. After the reduction, noticeable Cr(III) precipitates were accumulated on bacterial surfaces, but 37.5% Cr(III) still remained in the supernatant. For biofilms, the biofilm debris became the main active ingredient of the Cr(VI) reduction. However, only 20 mg/L Cr(VI) could be reduced probably because of unavailability of reducing active sites during the biofilm formation. Further studies showed that biofilms had a better Cr(III) immobilization capacity than planktonic cells with 100% Cr(III) immobilized. Moreover, for the first time, we proposed a strategy combining the advantages of both planktonic cells and biofilms, and a successful Cr(VI) removal from typical Cr(VI)-containing plating wastewater was achieved through a 10-L pilot-scale experiment.

Background: Internal carotid artery (ICA) hypoplasia (ICAH) is rare. The classification of ICAH is largely unclear. The aim of the study is to propose a new imaging classification for ICAH based on the occlusion of the distal ophthalmic segment and discuss the clinical and radiological differences between the different types. Materials and Methods: This was a retrospective study of patients with congenital ICAH diagnosed at the Department of Neurology of the China-Japan Friendship Hospital between June 2011 and June 2016. The patients underwent temporal bone computed tomography (CT), brain CT, cranial magnetic resonance imaging, transcranial Doppler, and head and neck CT angiography. Results: A total of 20 ICAH patients were divided into the distal occlusion (12 cases; 60%) and nondistal occlusion (8 cases; 40%) types based on whether the distal ophthalmic segment was occluded. The frequencies of collateral circulation from the circle of Willis (P = .01) and dilated cerebrovascular lesions (P = .001) in the distal occlusion type was higher than in the nondistal occlusion type. Five (25%) patients developed adverse cerebrovascular events during followup: 3 ischemic cases were of the nondistal occlusion type, and 2 cases with subarachnoid hemorrhage were of the distal occlusion type. Conclusions: A novel classification of ICAH was revealed based on the occlusion of the distal ophthalmic segment. The 2 types may show differences in collateral circulation patterns, coexisting cerebrovascular abnormalities, and potential clinical outcomes.