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Objective: There is concern that the coronavirus disease (COVID-19) vaccine may trigger or worsen autoimmune diseases. The objective of this study was to determine the impacts of COVID-19 vaccination on symptom severity in patients with myasthenia gravis (MG). Methods: A total of 106 enrolled patients with MG who were vaccinated against COVID-19 were followed up, and a questionnaire was used to document in detail the exacerbation of muscle weakness after vaccination and all other uncomfortable reactions after vaccination. Demographic, clinical characteristics, medication, and vaccination data were collected by follow-up interview. The main observation outcome was whether the MG symptoms of patients were exacerbated. The definition of exacerbation is according to the subjective feeling of the patient or a 2-point increase in daily life myasthenia gravis activity score relative to before vaccination, within 30 days after vaccination. Results: Of 106 enrolled patients [median age (SD) 41.0 years, 38 (35.8%) men, 53 (50.0%) with generalized MG, 74 (69.8%) positive for acetylcholine receptor antibody, and 21 (19.8%) with accompanying thymoma], muscle weakness symptoms were stable in 102 (96.2%) patients before vaccine inoculation. Muscle weakness worsened in 10 (9.4%) people after vaccination, of which 8 patients reported slight symptom worsening that resolved quickly (within a few days). Two (1.9%) of patients showed serious symptom aggravation that required hospitalization. Conclusion: Our results suggest that inactivated virus vaccines against COVID-19 may be safe for patients with MG whose condition is stable. Patients with generalized MG may be more likely to develop increased muscle weakness after vaccination. [ABSTRACT FROM AUTHOR]

The goal of the paper was to investigate the effect of the catalyst precursor on the catalytic activity. For this reason, the structure, the reducibility and the reaction behavior of γ-Al2O3-supported Co (24 wt%) catalysts as a function of calcination temperature ( Tc) were investigated using X-ray diffraction, temperature-programmed reduction, CO chemisorption, pulse reaction with pure CH4, and the catalytic reactions of methane conversion to synthesis gas. Depending on Tc, one, two, or three of the following Co-containing compounds, Co3O4, Co2AlO4, and CoAl2O4, were identified. Their reducibility decreased in the sequence: Co3O4>Co2AlO4>CoAl2O4. Co3O4 was generated as a major phase at a Tc of 500°C and Co2AlO4 and CoAl2O4 at a Tc of 1000°C. The reduced Co/γ-Al2O3 catalysts, obtained via the reduction of the 500 and 1000°C calcined catalysts, provided high and stable activities for the partial oxidation of methane and the combined partial oxidation and CO2 reforming of methane. They deactivated, however, rapidly in the CO2 reforming of methane. Possible explanations for the stability are provided. [ABSTRACT FROM AUTHOR]

The combined partial oxidation and CO2 reforming of methane to synthesis gas was investigated over the reduced Co/MgO, Co/CaO, and Co/SiO2 catalysts. Only Co/MgO has proved to be a highly efficient and stable catalyst. It provided about 94–95% yields to H2 and CO at the high space velocity of 105 000 ml g−1 h−1 and for feed ratios CH4/CO2/O2=4/2/1, without any deactivation for a period of study of 110 h. In contrast, the reduced Co/CaO and Co/SiO2 provided no activity for the formation of H2 and CO. The structure and reducibility of the calcined catalysts were examined using X-ray diffraction and temperature-programmed reduction, respectively. A solid solution of CoO and MgO, which was difficult to reduce, was identified in the 800 °C calcined MgO-supported catalyst. The strong interactions induced by the formation of the solid solution are responsible for its superior activity in the combined reaction. The effects of reaction temperature, space velocity, and O2/CO2 ratio in the feed gases (while keeping the C/O ratio constant at 1/1) were investigated over the Co/MgO catalyst. The H2/CO ratio in the product of the combined reaction increased with increasing O2/CO2 ratio in the feed. [ABSTRACT FROM AUTHOR]

The structural characteristics and the reduction behavior of the Co/MgO catalysts were investigated using temperature programmed reduction (TPR) and X ray diffraction (XRD). The variables investigated included the preparation method and the heat treatment conditions (calcination temperature and time). Depending on these factors, one, two or three of the following Co containing species, Co3O4, MgCo2O4 and (Co, Mg)O (solid solution of CoO and MgO) were identified. The extent of solid solution formation increased as the calcination temperature and calcination time increased. A much lower calcination temperature was needed to form a solid solution in the impregnated catalysts than in the physically mixed ones. The formation of a solid solution rendered the catalyst less reducible. Finally, the decomposition of CH4, as a probe reaction, was performed and it was found that the amount of carbon deposited decreased with increasing extent of solid solution formation. [ABSTRACT FROM AUTHOR]

Fetal iodine deficiency disorder (FIDD) is the principal form of endemic cretinism, and the most common cause of preventable mental deficiency in the world. However not everyone at risk develops FIDD and familial aggregation is common. This suggests that genetic factors may also be involved. The Apolipoprotein E (APOE) gene encodes for a lipoprotein that possesses a thyroid hormone binding domain, and APOE genotype may affect the efficiency with which thyroid hormone influences neuronal cell growth during the first and second trimesters of fetal development. We have compared ApoE genotypes in 91 FIDD cases with 154 local control subjects, recruited from three iodine deficiency areas in central China. We have also genotyped 42 FIDD family cases and 158 normal individuals from the families of local controls, and 375 population controls from Shanghai. APOE ∈4 genotypes were significantly enriched in FIDD probands from each of the three iodine deficiency areas; the ∈4 allele frequency was 16% vs 6% in controls. The same effect was also observed when we compared FIDD family cases with controls and control families. Our data suggest that in iodine-deficient areas, the APOE ∈4 allele is a genetic risk factor for FIDD. The phenomenon may affect population selection and contribute to the low frequency of the ∈4 allele in Chinese compared to Caucasian populations. [ABSTRACT FROM AUTHOR]

Abstract. The structure and magnetic properties of Fe-N and Fe-Ti-N films have been studied as a function of annealing temperature T[sub a] with a transmission electron microscope and a vibrating sample magnetometer. The as-prepared Fe-N films consist of the gamma-Fe[sub 4]N and alpha"-Fe[sub l6]N[sub 2] phases, and the Fe-Ti-N films are composed of the gamma'-Fe[sub 4]N, alpha"-Fe[sub l6]N[sub 2], and TiN phases. The structural changes with annealing temperature in the Fe-N films are distinct. The alpha"-Fe[sub l6]N[sub 2] decomposes into alpha + gamma' phases in the Fe-N film annealed at about 300 Celsius, and it disappears in the film annealed at 350 Celsius. Annealing of the Fe-Ti-N films shows no structural changes between room temperature (RT) and 500 Celsius. The saturation magnetization 4piM[sub S] and coercivity H[sub c] of the Fe--N films change drastically with the annealing temperature T[sub a], whereas those of the Fe-Ti-N films do not change with T[sub a] up to 500 Celsius. These results indicate that the additon of Ti may improve the thermal stability of Fe-N films. [ABSTRACT FROM AUTHOR]

The partial oxidation of methane was studied over γ-Al2O3-supported catalysts for Rh loadings between 0.01 and 5.0 wt%. It was found that the activity and selectivities for loadings between 0.5 and 5.0 wt% are almost the same. As an example, detailed information is presented for the 1.0 wt% Rh/γ-Al2O3, which provides at 750°C (furnace temperature) an activity of 82% and selectivities of 96% to CO and 98% to H2, at a gas hourly space velocity (GHSV) of 720000 ml g−1 h−1. Its activity remained stable during our experiment which lasted 120 h. Possible explanations for this high stability are proposed based on TPR and XRD experiments. Pulse reactions with small pulses of CH4 and CH4/O2 (2/1) were performed over the reduced and unreduced Rh catalysts to probe the mechanistic aspects of the reaction. The partial oxidation of methane to syngas was found to be initiated by metallic rhodium sites, since the CO selectivity increased with increasing number of such sites. [ABSTRACT FROM AUTHOR]

FeCoN films with 0–40 at.% Co contents were prepared by facing targets sputtering. The effects of the substrate temperature (T[sub s] ) and Co content on the structure and magnetic properties of FeCoN films are investigated. The phases formed in FeCoN films are strongly dependent on the substrate temperature. At T[sub s] =100 °C, to the growth of α[sup ′′] –(Fe,Co)[sub 16] N[sub 2] phase is favored. Enhancement of the formation of α[sup ′′] phase by Co addition was observed. Films with 5–25 at.% Co contents deposited at T[sub s] =100 °C exhibit high saturation magnetization up to the range of 2.5–2.7 T. The saturation magnetization of α[sup ′′] alloys phase is expected to be 2.8–2.9 T, which is as large as that of α[sup ′′] –Fe[sub 16] N[sub 2] reported by Sugita et al., and this confirms the high saturation magnetization of the α[sup ′′] phase. [ABSTRACT FROM AUTHOR]

Examines the friction-wear characteristics of carbon fiber reinforced friction material (CFRFM). Phenolic resin as the binder in polymeric brake materials due to its thermal stability; Determination of the wear rate of a specimen by weighing the specimen before and after a wear test; Effect of the surface characteristics of carbon fiber on the wear behavior of CFRFM.