RESUMO
Hydrogen (H2), produced by water electrolysis with the electricity from renewable sources, is an ideal energy carrier for achieving a carbon-neutral and sustainable society. Hydrogen evolution reaction (HER) is the cathodic half-reaction of water electrolysis, which requires active and robust electrocatalysts to reduce the energy consumption for H2 generation. Despite numerous electrocatalysts have been reported by the academia for HER, most of them were only tested under relatively small current densities for a short period, which cannot meet the requirements for industrial water electrolysis. To bridge the gap between academia and industry, it is crucial to develop highly active HER electrocatalysts which can operate at large current densities for a long time. In this review, the mechanisms of HER in acidic and alkaline electrolytes are firstly introduced. Then, design strategies towards high-performance large-current-density HER electrocatalysts from five aspects including number of active sites, intrinsic activity of each site, charge transfer, mass transfer, and stability are discussed via featured examples. Finally, our own insights about the challenges and future opportunities in this emerging field are presented.
RESUMO
OBJECTIVE: To describe the clinical and neuroimaging features, treatment response and outcomes of adult myelin oligodendrocyte glycoprotein (MOG) antibody-associated cortical encephalitis. METHODS: In this retrospective study, adult patients fulling the criteria of encephalitis but not fulfilling those of ADEM and tested positive for serum MOG antibody were recruited from Xiangya Hospital, Central South University (2019-2021). Clinical symptoms, laboratory data, imaging, and outcomes were analyzed. RESULTS: Eleven MOG antibody-associated cortical encephalitis patients consisting of 4 female (36.4%) and 7 male (63.6%) were included with a median onset age of 27 years (ranging: 16-32 years). Fever (8/11), headache (9/11) and seizures (7/11) were the most common symptoms of adult MOG cortical encephalitis, and generalized seizure was the dominant seizure type (4/7). Increased intracranial pressure (5/10, median 280 mm H2O, ranging 240-380 mm H2O), CSF pleocytosis (5/10, median 48 cells/µL, ranging: 18-1800 cells/µL), and protein elevation (4/10, median 0.67 g/L, ranging: 0.46-1.92 g/L) were common. Serum MOG antibody was detected in all patients and the coexistence of CSF NMDAR antibody was found in one case. Imaging showed abnormal brain MRI in 10 patients (90.9%) and 10/10 had the cortical involvement. 8/10 had unilateral lesions while 2/10 had bilateral lesions. 2/10 had the juxta cortical white matter lesions and 2/10 had the corpus callosum lesions. No involvement of deep gray matter or other white matter structure was noted. 5/11 had leptomeningeal and/or lesional enhancements. 10/11 patients had favorable outcomes and 2/11 had clinical relapses with persisting MOG antibody positive during the median follow-up interval of 10 months (ranging: 3-23months). CONCLUSION: Atypical clinical features for demyelinating diseases including seizures, remarkably increased intracranial pressure, pleocytosis, and protein elevation are common in MOG cortical encephalitis. Involvement of the corpus callosum and cortex around the midline could be unique imaging features of MOG antibody-associated bilateral cortical encephalitis.