Clinical characteristics of overseas imported and related local COVID-19 patients in Chengdu / 中国胸心血管外科临床杂志

@#Objective    To study the clinical characteristics of overseas imported and related local COVID-19 patients in Chengdu. Methods    Fifty overseas imported patients who were Chinese and 14 related local patients with COVID-19 who were admitted to Public Health Clinical Center of Chengdu from November to December 2020 were selected. The epidemiological characteristics, clinical manifestations, auxiliary examination, treatment and prognosis were summarized and analyzed. Results    The local group were older, and they were mostly elderly and females (P≤0.05). Compared with the imported group, the proportion of the local group was higher in heart disease and tumor. More patients had cough, fever and expectoration symptoms (P≤0.05). C-reactive protein, fasting blood glucose and fibrinogen were higher, and the lymphocyte count, blood platelet count, CD3+ T lymphocyte count, CD4+ T lymphocyte count, CD8+ T lymphocyte count were lower. The positive rate of novel coronavirus total antibody, IgG antibody and IgM antibody in the imported group were higher than those in the local group (P≤0.05). The negative conversion time of the median nucleic acid was shorter than that of local patients (P≤0.05). Conclusion    There are differences in sex ratio, age, complications, clinical manifestations, lymphocyte measurement value, T lymphocyte count and negative conversion time of nucleic acid between overseas imported and local COVID-19 patients in Chengdu. The local patients are mostly elderly and have more complicated conditions, but all of them have good prognosis.

Low-cost, large-scale, and facile production of Si nanowires exhibiting enhanced third-order optical nonlinearity.

A facile method for the low-cost and large-scale production of silicon nanowires has been developed. Silicon powders were subjected to sequential metal plating and metal-assisted chemical etching, resulting in well-defined silicon nanowires. The morphology and structure of the silicon nanowires were investigated, revealing that single-crystal silicon nanowires with average diameters of 79 ± 35 nm and length more than 10 µm can be fabricated. The silicon nanowires show excellent third-order nonlinear optical properties, with a third-order susceptibility much larger than that of bulk silicon, porous silicon, and silicon nanocrystals embedded in SiO(2).