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Aimed at the staring imaging requirements of the low earth orbit (LEO) satellite array camera for aerial dynamic targets, a method for target position estimation and staring attitude planning based on image miss-distance of the satellite platform is proposed. Based on the prior knowledge of the flying altitude of the aerial dynamic target, taking the latitude and longitude change rate of the target geography as the state quantity and the central pixel value of the target as the observation, an extended Kalman filter (EKF) is designed to realize the accurate smooth estimation and prediction of the geographical latitude and longitude of the target. On this basis, the attitude and angular velocity of the satellite are planned, the influence of target pixel noise and delay on attitude stability is avoided, and the position estimation of a single satellite to target is realized. The effectiveness of the proposed method is illustrated by a numerical simulation.

Long non-coding RNA (lncRNA) LINC00891 knockdown is associated with poor prognosis of lung adenocarcinoma, but the underlying mechanism remains to be further explored. Here, we found that LINC00891 expression is downregulated in lung cancer tissues and cell lines compared with that in adjacent normal tissues and normal lung epithelial cells. LINC00891 overexpression impedes cell proliferation, invasion, migration and epithelial-to-mesenchymal transition (EMT) process in lung cancer cells. Mechanistic research showed that GATA2 directly binds to LINC00891 promoter and transcriptionally regulates LINC00891 expression. Meanwhile, GATA2 was identified as a target of miR-128-3p, and it is negatively regulated by miR-128-3p. Moreover, overexpression of GATA2 suppresses lung cancer cell proliferation, invasion, migration, and EMT process. Furthermore, LINC00891 restrains the RhoA pathway activity, and treatment with CCG-1423 (a specific RhoA pathway inhibitor) antagonizes the promoting effect of LINC00891 knockdown on cell malignant behaviors. Additionally, silencing of LINC00891 promotes xenograft tumor growth, which can be reversed by administration with CCG-1423. In summary, LINC00891 regulated by the miR-128-3p/GATA2 axis restrains lung cancer cell malignant progression and hinders xenograft tumor growth by suppressing the RhoA pathway.

The regenerative treatment of infectious vertical bone defects remains difficult and challenging today. Current clinical treatments are limited in their ability to control bacteria and infection, which is unfavorable for new bone formation and calls for a new type of material with excellent osteogenic and antibacterial properties. Here a multifunctional scaffold is synthesized that mimics natural bone nanostructures by incorporating silver nanowires into a hierarchical, intrafibrillar mineralized collagen matrix (IMC/AgNWs), to achieve the therapeutic goals of inhibiting bacterial activity and promoting infectious alveolar bone augmentation in rats and beagle dogs. An appropriate concentration of 0.5 mg mL−1 AgNWs is selected to balance biocompatibility and antibacterial properties. The achieved IMC/AgNWs exhibit a broad spectrum of antimicrobial properties against Gram‐negative Porphyromonas gingivalis and Gram‐positive Streptococcus mutans. When the IMC/AgNWs are cocultured with periodontal ligament stem cells, it possesses excellent osteoinductive activities under both non‐inflammatory and inflammatory conditions. By constructing a rat mandibular infected periodontal defect model, the IMC/AgNWs achieve a near‐complete healing through the canonical BMP/Smad signaling. Moreover, the IMC/AgNWs enhance vertical bone height and osseointegration in peri‐implantitis in beagle dogs, indicating the clinical translational potential of IMC/AgNWs for infectious vertical bone augmentation. [ABSTRACT FROM AUTHOR]

The present study examined how undergraduate students from a prestigious Chinese university perceived the teaching and learning of English for general academic purposes (EGAP) reading and writing courses. Analyses of 951 questionnaires revealed that most participants generally (strongly) believed that learning general academic English was closely related to their major study, reported being motivated to learn general academic English, and expected to improve their academic English reading, writing, listening and speaking skills from EGAP courses. The study also showed that they had consensus about the requirements and teaching and learning foci of general academic English in spite of their concerns about academic English, and that students of more demanding and more academic EGAP courses tended to have a better understanding of general academic English. Based on the findings, some suggestions are discussed.