Serving as the electrical to optical converter, the on-chip silicon light source is an indispensable component of silicon photonic technologies and has long been pursued. Here, we briefly review the history and recent progress of a few promising contenders for on-chip light sources in terms of operating wavelength, pump condition, power consumption, and fabrication process. Additionally, the performance of each contender is also assessed with respect to thermal stability, which is a crucial parameter to consider in complex optoelectronic integrated circuits (OEICs) and optical interconnections. Currently, III-V-based silicon (Si) lasers formed via bonding techniques demonstrate the best performance and display the best opportunity for commercial usage in the near future. However, in the long term, direct hetero-epitaxial growth of III-V materials on Si seems more promising for low-cost, high-yield fabrication. The demonstration of high-performance quantum dot (QD) lasers monolithically grown on Si strongly forecasts its feasibility and enormous potential for on-chip lasers. The superior temperature-insensitive characteristics of the QD laser promote this design in large-scale high-density OEICs. The Germanium (Ge)-on-Si laser is also competitive for large-scale monolithic integration in the future. Compared with a III-V-based Si laser, the biggest potential advantage of a Ge-on-Si laser lies in its material and processing compatibility with Si technology. Additionally, the versatility of Ge facilitates photon emission, modulation, and detection simultaneously with a simple process complexity and low cost.

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Background Coronavirus disease 2019 (COVID-19) induces myocardial injury, either direct myocarditis or indirect injury due to systemic inflammatory response. Myocardial involvement has been proved to be one of the primary manifestations of COVID-19 infection, according to laboratory test, autopsy, and cardiovascular magnetic resonance (CMR). However, the middle-term outcome of cardiac involvement after the patients were discharged from the hospital is yet unknown. The present study aimed to evaluate mid-term cardiac sequelae in recovered COVID-19 patients by CMR Methods A total of 47 recovered COVID-19 patients were prospectively recruited and underwent CMR examination. The CMR protocol consisted of black blood fat-suppressed T2 weighted imaging, T2 star mapping, left ventricle (LV) cine imaging, pre- and post-contrast T1 mapping, and late gadolinium enhancement (LGE). LGE were assessed in mixed both recovered COVID-19 patients and healthy controls. The LV and right ventricle (RV) function and LV mass were assessed and compared with healthy controls. Results A total of 44 recovered COVID-19 patients and 31 healthy controls were studied. LGE was found in 13 (30%) of COVID-19 patients. All LGE lesions were located in the mid myocardium and/or sub-epicardium with a scattered distribution. Further analysis showed that LGE-positive patients had significantly decreased LV peak global circumferential strain (GCS), RV peak GCS, RV peak global longitudinal strain (GLS) as compared to non-LGE patients (p < 0.05), while no difference was found between the non-LGE patients and healthy controls. Conclusion Myocardium injury existed in 30% of COVID-19 patients. These patients have depressed LV GCS and peak RV strains at the 3-month follow-up. CMR can monitor the COVID-19-induced myocarditis progression, and CMR strain analysis is a sensitive tool to evaluate the recovery of LV and RV dysfunction.

Acute pancreatitis patients increased year by year in Beijing. Gallstones were the predominant etiological factor. There were different etiology proportion of AP according age, sex, and severity.