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It is of great significance to provide early warning for vehicle collisions on urban roads. In order to overcome the high missing rate and low warning accuracy and poor efficiency of traditional early warning methods, an urban road vehicle collision early warning method based on Internet of Vehicles data was proposed. The extended Kalman filter is used to estimate the vehicle attitude on urban roads, and the vehicle longitudinal safety distance model is established. Based on the Internet of Vehicles, the position, speed, acceleration and heading information of follow-up vehicles on urban roads and vehicles in front of urban roads are obtained, and the dispersion of vehicle spacing changes is obtained. The dispersion is used as the judgment threshold of urban road vehicle collision warning to realize collision warning. The experimental results show that the average false alarm rate is 1.2%, the maximum false alarm rate is only 1%, and the alarm time is only 19.9s. [ABSTRACT FROM AUTHOR]

OBJECTIVE: In December 2019, a new type of coronavirus-infected pneumonia broke out in Wuhan and spread rapidly to other parts of the country. The purpose of this study was to investigate the clinical features of coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS: A retrospective analysis was performed on the confirmed cases of COVID-19, who were admitted to the North Hospital of Changsha first Hospital (Changsha Public Health treatment Center) from January 17 to February 7, 2020. RESULTS: The median age of COVID-19 patients was 45 years (range 33.5-57). The male patients accounted for 49.7%, 64.6% of the patients had a history of exposure in Wuhan, and 31.7% had family aggregation. The median days of onset were six, and the incidence of severe illness was 18.6%. Compared with the non-severe group, the severe group showed statistical significance in older age, hypertension, bilateral lung plaque shadow, decrease in lymphocyte count, increase in C-reactive protein (CRP), aspartate aminotransferase (AST), lactate dehydrogenase, and creatine kinase. CONCLUSIONS: Age, combined hypertension, oxygenation index, double lung patch, decreased lymphocyte count, and elevated levels of C-reactive protein, aspartate aminotransferase, lactate dehydrogenase, and creatine kinase can be used as predictors of the disease severity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MicroRNAs have been implicated to play a crucial regulating role in human cancers. The study aims to explore the role and clinical significance of miR-497 in pancreatic ductal adenocarcinoma (PDAC). PATIENTS AND METHODS: The relative expression of miR-497 in human PDAC tissue samples and adjacent normal tissues was measured using the quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell Counting Kit (CCK-8) assay, cell migration, and invasion assays were performed to detect cell proliferation and invasion ability. Downstream target gene was confirmed by using luciferase activity assays. QRT-PCR and Western blotting assays also were performed. RESULTS: We found that miR-497 expression was significantly downregulated in PDAC tissues and cells. Lower miR-497 expression associated with lymph node metastasis and predicts a poor prognosis in PDAC patients. In in vitro assay, we demonstrated that miR-497 overexpression inhibited cell proliferation, migration, and invasion of PDAC. Furthermore, we demonstrated that HMGA2 was a direct target of miR-497 in PDAC cells. MiR-497 inhibited cell proliferation and invasion by regulating HMGA2 expression. CONCLUSIONS: Our results indicated that miR-497 may serve as a predictor for PDAC and could be a novel target of PDAC treatment. [ABSTRACT FROM AUTHOR]

Exciton dissociation process at indium tin oxide (ITO)/copper phthalocyanine (CuPc) interface of ITO/CuPc(370 nm)/Al is studied by transient photovoltage method. A negative-to-positive change in the polarity of photovoltage upon pulsed laser irradiation is observed in CuPc thin film. The polarity change is regarded as a summation of the effect of exciton dissociation at ITO/CuPc interface (fast process) and that of free carrier separation by built-in field (slow process). Further experiments confirm the existence of exciton dissociation at ITO/CuPc interface, and the direction of which is electron injected into ITO, with holes left in CuPc film. This is opposite to that of the interfacial dissociation at donor/acceptor (D/A) interface in single heterojunction cells (ITO/D/A/buffer/Al). 3-nm-thick LiF insulating layer is inserted between ITO and CuPc to inhibit the exciton dissociation at ITO/CuPc interface. Thereby, the open-circuit voltage and power conversion efficiency of the single layer cell have been increased by several times. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The paper aims to explore the application of dexmedetomidine combined with dezocine in thoracoscopic radical resection of lung cancer and its effect on the awakening quality. PATIENTS AND METHODS: 122 patients undergoing thoracoscopic radical resection of lung cancer in The Affiliated Hospital of Qingdao University from April 2009 to January 2012 were selected as the subjects of the study. Among them, 68 patients were anesthetized with dexmedetomidine combined with dezocine as a study group, 54 patients with midazolam combined with fentanyl as a control group. The onset of anesthetic, operation time, awakening time, extubation time, and recovery time was compared. The mean arterial pressure (MAP), central venous pressure (CVP), and heart rate (HR) were compared before anesthesia (t0), at extubation (t1), 10 min after extubation (t2), and when patients left anesthesia recovery room (t3). The postoperative sedation score (Ramsay), modified the objective pain score (MOPS), and the pediatric anesthesia emergence delirium (PAED) score were compared at the time of the postoperative awakening (b1), 30 min after awakening (b2), 1 hour after awakening (b3), and 3 hours after awakening (b4). RESULTS: There was no significant difference in MAP, CVP, and HR between the study group and the control group at t0 (p > 0.05). The scores of PAED at b3 and b4 in the study group were lower than those in the control group (p < 0.05). CONCLUSIONS: The anesthesia effect of dexmedetomidine combined with dezocine in thoracoscopic radical resection of lung cancer is better and safer than other drugs, and it can produce good sedation and analgesic effect. [ABSTRACT FROM AUTHOR]

In order to detect the debonding defects in the steel-lead adhesive structure, and taking into account the particularity of its application, a new type of non-contact laser ultrasonic testing technology was adopted. The numerical model of steel-lead adhesive structure was established, the distribution law of temperature field on the surface of metal material irradiated by pulsed laser and the selection principle of laser parameters were analysed. The difference of laser ultrasonic signal between the intact bonding structure and debonding structure was analysed by transmission method and pulse reflection method respectively. And the transmission and reflection shear wave were selected to discriminate the debonding defects in the steel-lead adhesive structure. The results show that laser ultrasonic technology can realize the non-destructive testing of debonding defects in the steel-lead metal bonding structure, and has wide application prospect in weapon equipment, aerospace and other fieldls. [ABSTRACT FROM AUTHOR]