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Direct aging of water-quenched metastable β-titanium alloys usually follows the sequence: rapid growth of ωiso and then slow transformation into α. To inhibit ωiso growth and promote α nucleation, 6% pre-deformation was introduced in Ti-10V-6Cu alloy before 500°C/60s aging. An ultrafast α-formation and a few α-free kink-bands are observed, indicating the alteration of the precipitation sequence. For α-nucleation without ωiso as the sites, it shows that O' nanodomains induced by stress accumulation around slip bands mediate the ultrafast nucleation of hcp-α structure, while dislocation pipe diffusion accelerates the necessary phase separation. This provides new insights into regulating precipitation kinetics of age-hardenable β-titanium alloys. [ABSTRACT FROM AUTHOR]

In this paper, experimental observation and numerical calculation are applied to investigate the vortex-cavitation interactionin the blade tip region. Calculated performances have good agreement with experimental results. The evolution of TLVC is analysed byHigh-speed photography (HSP) at the selected cavitation condition. Liutex method was adopted to identify the tip leakage vortex (TLV)core centre. According to the radial location of the TLV core centre and the development of TLVC, the flow along the blade can bedivided into three regimes: stable cavitation, unstable cavitation and non-cavitation flow. Tip leakage flow (TLF) and main flow haveeffects on the TLV intensity and trajectory. Finally, different terms of vorticity transport equation were used to analyse the contributionof cavitation to the production and reallocation of vorticity in a rotating frame. It shows that circumferential dilatation and axial vortexstretching terms mainly contribute to vorticity production and its relocation. [ABSTRACT FROM AUTHOR]

Improving the digital citizenship of secondary vocational students is critical for cultivating vocational talents in education. It is an inevitable requirement for modernizing vocational education. Focusing on social media competence, this study explores possible ways to improve the digital citizenship of secondary vocational students. A total of 469 secondary vocational students in Wuhan city, Hubei province, were investigated using questionnaires. The data analysis shows that the four dimensions of social media competence (technical use, content interpretation, content generation, and anticipatory reflection) significantly predict digital citizenship. On this basis, we propose four paths for improving the digital citizenship of secondary vocational students: creating a suitable environment for secondary vocational students to apply their skills in information technology; enhancing the ability of secondary vocational students to discriminate about information on the Internet; improving students' interpersonal communication ability when dealing with technical support; building an early warning system for secondary vocational students' behavioral perception. [ABSTRACT FROM AUTHOR]

Complications affect the outcome of patients with cirrhosis. The favorable prognosis of patients with Wilson disease (WD)-related cirrhosis suggests that its complications differ from those of hepatitis B virus (HBV) infection-related cirrhosis. We aimed to delineate the differences in complications between WD-related and HBV-related cirrhosis. The electronic-medical data from patients with WD-related and HBV-related cirrhosis were extracted and analyzed. In total, 211 patients with WD-related cirrhosis and 374 patients with HBV-related cirrhosis were enrolled. Most patients with WD progressed to cirrhosis <10 years after disease onset, whereas those with HBV infection often progressed after >10 years. Patients with WD-related cirrhosis had a markedly lower prevalence of ascites (8.5% vs. 38.5%), gastroesophageal varices/variceal bleeding (13.3% vs. 47.6%), renal impairment (0 vs. 7.6%) and primary liver cancer (0 vs. 39.3%; all p <.001) than those with HBV-related cirrhosis. After adjustment for potential confounders, patients with WD-related cirrhosis carried a lower risk of varices/variceal bleeding. Although patients with WD progressed to cirrhosis much faster, the prevalence of complications from WD-related cirrhosis was low. Patients with WD-related cirrhosis were less likely to develop gastroesophageal varices/variceal bleeding than those with HBV-related cirrhosis. [ABSTRACT FROM AUTHOR]

Based on an extensive literature review, in this study we proposed a model of influencing factors that affect teachers' intention to adopt mobile devices in teaching. An online survey questionnaire was developed to investigate K-12 teachers' intention to adopt mobile devices in teaching and the influencing factors of that intention. Partial least squares (PLS) was employed to validate the proposed model and hypotheses using data collected from 132 primary and secondary school teachers. Results showed that teachers' attitude and technology beliefs, and their self-efficacy regarding mobile-based teaching had significant positive impacts on their intention to adopt mobile devices in teaching. Meanwhile, teachers' mobile device skills and mobile-based pedagogical knowledge strongly influenced their self-efficacy of mobile device-based teaching. Finally, the subject culture clash had a significant negative influence on teachers' attitudes, technology beliefs, and self-efficacy toward mobile-based teaching. Based on these findings, we put forward a number of suggestions to promote teaching using mobile devices. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have emerged as critical regulators for gene expression in multiple levels and thus are involved in various physiological and pathological processes. Sirtuin 1 (SIRT1) has been established to exert key roles in the diverse biological process through deacetylation of substrates, including DNA damage repair. Nevertheless, the regulatory relationship between SIRT1 and lncRNAs, and the effect of lncRNA on SIRT1-mediated functions were still far to be elucidated. We herein uncovered that lncRNA miR17HG was notably down-regulated in SIRT1-deficient cells, and significantly up-regulated after ectopic expression of SIRT1. Subsequently, the results of dual luciferase reporter (DLR) showed that SIRT1 dramatically enhanced the promoter activity of the miR-17-92 cluster. Furthermore, we specifically knocked down the previous demonstrated transcription factor for the miR-17-92 cluster, C-Myc, which was the validated substrate of SIRT1. As expected, miR17HG and miR-17-92 miRNAs were evidently down-regulated after silencing of C-Myc; and silencing of C-Myc significantly reversed the effect of SIRT1 on miR17HG expression, suggesting that SIRT1 endowed cells with elevated miR17HG expression through stabilization of C-Myc. What is more, silencing of miR17HG significantly inhibited the repair of DNA DSBs, while enforced expression of miR17HG promoted DSBs repair. Fascinatingly, overexpression of miR17HG evidently enhanced the deacetylation activity of SIRT1, while silencing of miR17HG conferred diminished deacetylation activity. In addition, the results of RIP unraveled the physical interaction between miR17HG and SIRT1. Taken together, we presented evidences that miR17HG and SIRT1 probably formed a positive feedback loop, which exerted a crucial effect on DSBs repair. [ABSTRACT FROM AUTHOR]

The Internet, new media and social change have created issues requiring digital citizenship education, particularly within the socio-cultural context of Chinese education. Recent digital citizenship standards for education developed by organizations such as the International Society for Technology in Education (ISTE) highlight the importance of this issue. Researchers have explored digital citizenship with some mediated behavioral determinants; however, the critical influence of interpersonal communication competence (ICC) has not yet been explored. To expand understanding of the components needed for improving the appropriateness of digital citizenship among future role models of society, this study investigates the relationship between ICC skills and digital citizenship with a sample of 905 pre-service teachers. The results showed that 10 ICC skills were positively predictive of digital citizenship. Environmental control and immediacy were found to be the strongest predictors of digital citizenship among the skills examined. These results theoretically emphasize the importance of ICC skills in mediated behavior and provide practical direction for improving pre-service teachers' digital citizenship, which can positively enable the behavior instructors display and convey to their future students. [ABSTRACT FROM AUTHOR]

Lung cancer is one of the most common cancers and the leading cause of cancer-related death worldwide. Despite encouraging results achieved with targeted therapy in recent years, the early diagnosis and treatment of lung cancer remains a major problem. Circular RNA (circRNA), a type of RNA with covalently closed continuous loop structures, has structural stability and certain tissue specificity. Recent studies have found that circRNAs have an important role in tumor development and are expected to be revealed as new targets for tumor prediction and treatment. Research on the biological functions and regulation mechanisms of circRNAs in lung cancer is in its infancy but is gathering momentum. In this review, we discuss the properties, biogenesis, biological function, and research progress of circRNAs in lung cancer to provide a theoretical foundation and new directions for studies on circRNAs in lung cancer. [ABSTRACT FROM AUTHOR]

Although epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) gefitinib has exhibited notable clinical efficacy in non-small cell lung cancer (NSCLC) patients. However, its therapeutic efficacy is ultimately limited by the development of gefitinib resistance. The present study aimed to investigate the effects of the long non-coding RNA, RHPN1-AS1 on gefitinib resistance in NSCLC and explore the underlying mechanisms. In this study, RHPN1-AS1 was observed to be downregulated in gefitinib resistant patients and NSCLC cell lines. Besides, decreased expression of RHPN1-AS1 was found to be associated with poor prognosis of NSCLC patients. RHPN1-AS1 knockdown conferred gefitinib resistance to gefitinib sensitive NSCLC cells, whereas the overexpression of RHPN1-AS1 sensitized gefitinib resistant NSCLC cells to gefitinib treatment. Mechanistically, RHPN1-AS1 was found to positively regulate the expression of TNFSF12 by directly interacting with miR-299-3p. Collectively, RHPN1-AS1 modulates gefitinib resistance through miR-299-3p/TNFSF12 pathway in NSCLC. Our findings indicate that RHPN1-AS1 may serve as not only a prognostic biomarker for gefitinib resistance but also as a promising therapeutic biomarker and target for the treatment of NSCLC patients. [ABSTRACT FROM AUTHOR]

contraction twins that are commonly activated in α-titanium interact to each other and form three types of twin-twin junctions (, , TTJs) corresponding to the crystallography of six twin variants (i = 1,2, …, 6). We detected 243 TTJs in rolled pure α-titanium sheets. Electron backscatter diffraction analysis reveals that TTJs are profuse, 79.8% among three types while and TTJs take up 17.7 and 2.5%. Twin transmission does not occur. Consequently, boundaries associated with twin-twin interactions block twin propagation and influence twin growth. We explain structural features of TTJs according to the Schmid factor analysis and the reaction mechanism of twinning dislocations. The knowledge regarding TTJs provides insight for improving the predictive capability of meso/macro-scale crystal plasticity models for hexagonal metals. [ABSTRACT FROM AUTHOR]

The microstructure, composition and mechanical properties of the rostrum inCyrtotrachelus longimanus(JHC Fabre) were studied utilizing light, fluorescent, scanning electron microscopy (SEM) and energy-dispersive spectroscopy. SEM images show the morphological characteristics of rostrum’s cross section; it is a typical lightweight multilayer structure – one rigid exocuticle layer and dense endocuticle layers, which construct unevenly overlapping fiber structures. The composition analysis of the rostrum shows that it is mainly composed of C, H, N, O, as well as some metal elements and microelements, such as Mg, Si, Zn, Ca and Na, which contribute to its mechanical performance. The mechanical properties of the rostrum were tested by the electronic universal testing machine, which shows it has high-specific strength and is almost the same as that of the stainless steel. The results may provide a biological template to inspire biomimetic lightweight structure design. [ABSTRACT FROM PUBLISHER]

In the past few years, much work has been performed to explore the biomedical applications and toxicity of nano-graphene and its derivatives. However, the reproductive toxicity of those carbon nanomaterials has been rarely studied. In this study, we report on the male reproductive toxicity of nanoscale graphene oxide (GO) using a mouse model. The results showed that the adult male mice injected with high dosages of GO (25 mg/kg mouse) via the tail vein exhibited normal sex hormone secretion and retained normal reproductive activity. All untreated female mice mated with the GO-treated male mice could produce healthy pups. There were no significant differences in pup numbers, sex ratio, weights, pup survival rates or pup growth over time between the GO-treated and control groups. Furthermore, these GO-treated male mice could produce a second, third, fourth and even fifth litter of healthy offspring when they lived with the untreated female mice. The testicular and epididymal histology as well as the activities of several important epididymal enzymes including α-glucosidase, lactate dehydrogenase, glutathione peroxidase and acid phosphatase were not affected by GO treatment. In addition, no damaging effects were seen at high dose rates of GO (total 300 mg/kg male mouse, 60 mg/kg every 24 h for 5 days) via intra-abdominal injection. Thus, GO showed very low or nearly no toxicity for male reproduction. This work will greatly enable future investigations of GO nanosheets for in vivo biomedical applications. [ABSTRACT FROM AUTHOR]

Oestrogen receptor binding assay is an important approach to screen oestrogenic endocrine disruptors. But it is often expensive and radioactive pollution has existed. In order to screening endocrine disrupting chemicals (EDCs) without a radioactive label, we developed a new high-throughout method using gold nanoparticle technology. The assay is based on the competition binding between the oestrogenic EDCs in the sample and 17β-estradiol-BSA to the oestrogen receptor. The signal is from specific binding of gold nanoparticles labelled ERE to the ligand-receptor complex. The result showed that as little as 100 pg L-1 of 17β-estradiol could be detected with a linear range from 100 pg L-1 to 1 µg L-1 (R2 = 0.9764). The concentrations of oestrogenic EDCs in environmental sample determined by our method and by the cell (MCF-7) proliferation were not significantly different. The result presented led us to conclude that this method is an ideal screening method which is reliable, low-cost, rapid, high-throughout and could be performed on microplates or chips. [ABSTRACT FROM AUTHOR]

Objective: Venous compression might be the main cause of incomplete decompression and symptom recurrence after microvascular decompression (MVD) in patients with trigeminal neuralgia. Although it can be killed in most cases, cutting the vein sometimes has the potential risk arising from venous congestion. To maneuver the vein safely, we introduced a temporary occlusion test of the vein. Methods: Among 407 consecutive MVD cases, 48 (11.8%) offending and 157 block veins were encountered. The vein was cut directly in 147 (71.7%). Owing to the potential risk following killing of the vein, 58 (28.3%) patients underwent venous occlusion test with neurophysiologic monitoring during the operation. The temporal occlusion should be ceased immediately as soon as any changes in brainstem auditory evoked potential (BAEP) or trigeminal evoked potential (TEP) wave figuration turn up; otherwise, it would last for 15 minutes. Results: The occlusion test was negative in 53 (91.4%), while positive in five patients (8.6%). According to the results, we cut the vein in test-negative patients, which made the operation easy and offered a satisfactory decompression. Among the five positive cases, the vein was finally saved in two and cut in three cases. Yet, all the three patients developed a severe ipsilateral cerebellar edema and brainstem shift after the vein was sacrificed. Despite those patients were reoperated on immediately for posterior fossa decompression, they remained equilibrium disorder with numbness in ipsilateral face and mind hemiparesis in contralateral extremities post-operatively. The residual two patients had an incomplete pain relief. Conclusion: This venous occlusion test could help the surgeon in making a right decision before manipulation of the petrosal veins during MVD. [ABSTRACT FROM AUTHOR]