Currently, the tensor completion problem has been paid high attention in the machine learning, especially in the field of computer vision and image processing. The low-rank tensor completion methods based on the tensor singular value decomposition and the tensor nuclear norm minimization has been proposed. However, they have limitations in computing speed, since they are SVD-based methods and need high computational cost for high dimensional tensor. In this paper, based on the tensor QR decomposition and the tensor nuclear norm, a fast low-rank tensor completion method is proposed. By reducing the dimensions of the tensor in the nuclear norm regularization term, the performance of the completion is substantially improved. Numerical experiments for color images, MRI and videos demonstrate that the effectiveness of the proposed method.

Severe pneumonia (SP) is a respiratory tract disease that seriously threatens human health. The herpesvirus detected in patients, especially with severe and immunodeficient diseases, is gradually attracting the attention of clinical doctors. However, little is known about the effect of herpesvirus on the prognosis of SP patients and the pulmonary microbial community. Here, we retrospectively analyzed respiratory samples from 45 SP patients detected by metagenomic next-generation sequencing (mNGS). A total of five types of herpesviruses were detected, with Human alphaherpesvirus 1 (HHV-1) in 19 patients, Human betaherpesvirus 5 (CMV) in 7 patients, Human betaherpesvirus 7 (HHV-7) in 6 patients, Human alphaherpesvirus 2 (HHV-2) in 5 patients, and Human gammaherpesvirus 4 (EBV) in 4 patients. Further analysis showed that the mortality of the herpesvirus-positive group was significantly higher than that of the negative group. The results also showed that HHV-1 was significantly associated with the prognosis of SP patients, while the other herpesviruses did not have a significant difference in patient mortality. A comparison of the microbial community characteristics of SP patients showed a significant difference in beta-diversity between herpesvirus-positive and negative groups. Species difference analysis showed that the herpesvirus-positive group was related to more conditional pathogens, such as Pneumocystis jirovecii and Burkholderia cepacia. In summary, our results suggest that the presence of herpesvirus is associated with the mortality of SP patients. Furthermore, enrichment of conditional pathogens in the respiratory tract of herpesvirus-positive SP patients may be a potential reason for the increased mortality.

Governance innovation is an important topic in public administration research. Based on the empirical evidence of governance innovation in China, this paper analyzes the pathways to the sustainability of project-driven innovation in urban grassroots governance and reveals its complex causal relationships. Using the selected cases, a multidimensional analysis framework is constructed, and the qualitative comparative analysis method of fuzzy sets is used. It is found that there are three combined paths for the sustainability of innovation, namely dependent development, social embeddedness and government–society cooperation. The first two paths are the most common for the sustainability of innovation, and they cover most of the selected cases. Case tracking also reveals that innovation driven by project operation can stimulate the behavior of grassroots governance innovation, but it does not guarantee the sustainability of the innovation. The sustainability of innovation requires more mobilization of the grassroots society to enhance social embeddedness. Moreover, this study results provide inspiration for the sustainability of innovation in the later stages of projects.