Flame acceleration and deflagration-to-detonation transition (DDT) experiments were performed in a 28-cm-diameter, 6,4-m-long combustion duct filled with obstacles. The run-up distances (the distance ...between the ignition point and the location of onset of detonation) for DDT and the flame speeds just before onset of detonation were measured for detonable H2-airsteam mixtures. For less-sensitive mixtures, flame acceleration also occurred and choked velocities were reached within the length of the duct, but DDT events were not observed. Because of reflection of the precursor shock off the end plate, the gas mixture in the end gas region was further pressurized. Transition to detonation occurred in the end gas region for some of these less-sensitive mixtures. As a result of higher initial pressures, DDT in the end gas region produced very high overpressures at the end plate. Because of the high pressure and temperature created by the reflection of the precursor shock, the end gas region provides the most favorable conditions for DDT. If DDT did not occur in the end gas region, the resulting overpressures were found to be much lower. The pressure traces measured at the end gas region clearly indicated the limiting mixture composition for transition from deflagration to detonation. The limiting mixture composition, therefore, can be used to represent the transition limits for choked flames. However, being limited by the size of the end gas region, the present study does not reveal the effects of scale, particularly related to turbulence in the transition process. Thus, it is not certain whether the limiting mixture composition will be the same in situations in which turbulence also plays a key role in the transition process.
Pre-operative embolization of juvenile nasopharyngeal angiofibroma was performed in 15 patients. The lesion was supplied by the internal carotid arteries (8 cases), by the internal maxillary artery ...(15 cases), the accessory meningeal artery (10 cases) and the ascending pharyngeal artery (10 cases). Superselective embolization of the external carotid artery feeders was performed with Ivalon particles, without neurological complications. Good control of per-operative blood loss was noted in 13 out of 15 cases, 2 patients presenting severe per-operative venous bleeding. Recurrence was noted in only one patient, which could be controlled by reembolization.
AIM：To determine which patients might benefit most from retrograde viewing during colonoscopy through subset analysis of randomized,controlled trial data.METHODS：The Third Eye Retroscope Randomized ...Clinical Evaluation（TERRACE） was a randomized,controlled,multicenter trial designed to evaluate the efficacy of a retrograde-viewing auxiliary imaging device that is used during colonoscopy to provide a second video image which allows viewing of areas on the proximal aspect of haustral folds and flexures that are difficult to see with the colonoscope＇s forward view.We performed a post-hoc analysis of the TERRACE data to determine whether certain subsets of the patient population would gain more benefit than others from use of the device.Subjects were patients scheduled for colonoscopy for screening,surveillance or diagnostic workup,and each underwent same-day tandem examinations with standard colonoscopy（SC） and Third Eye colonoscopy（TEC）,randomized to SC followed by TEC or vice versa.RESULTS：Indication for colonoscopy was screening in 176/345 subjects（51.0%）,surveillance after previous polypectomy in 87（25.2%） and diagnostic workup in 82（23.8%）.In 4 subjects no indication was specified.Previously reported overall results had shown a net additional adenoma detection rate（ADR） with TEC of 23.2% compared to SC.Relative risk（RR） of missing adenomas with SC vs TEC as the initial procedure was 1.92（P = 0.029）.Post-hoc subset analysis shows additional ADRs for TEC compared to SC were 4.4% for screening,35.7% for surveillance,55.4% for diagnostic and 40.7% for surveillance and diagnostic combined.The RR of missing adenomas with SC vs TEC was 1.11（P = 0.815） for screening,3.15（P = 0.014） for surveillance,8.64（P = 0.039） for diagnostic and 3.34（P = 0.003） for surveillance and diagnostic combined.Although a multivariate Poisson regression suggested gender as a possibly significant factor,subset analysis showed that the difference between genders was not statistically significant.Age,bowel prep quality and withdrawal time did not significantly affect the RR of missing adenomas with SC vs TEC.Mean sizes of adenomas detected with TEC and SC were similar at 0.59 cm and 0.56 cm,respectively（P = NS）.CONCLUSION：TEC allows detection of significantly more adenomas compared to SC in patients undergoing surveillance or diagnostic workup,but not in screening patients（ClinicalTrials.gov Identifier：NCT01044732）.
2020 has become the year of coping with COVID-19. This year was to be the “super year” for sustainability, a year of strengthening global actions to accelerate the transformations required for ...achieving the 2030 agenda. We argue that 2020 can and must be a year of both. Thus we call for more utilisation of the health-emergency disaster risk management (Health-EDRM) framework to complement current responses to COVID-19 and the patent risk of similar phenomena in the future. To make our case, we examine current responses to COVID-19 and their implications for the SFDRR. We argue that current mechanisms and strategies for disaster resilience, as outlined in the SFDRR, can enhance responses to epidemics or global pandemics such as COVID-19. In this regard, we make several general and DRR-specific recommendations. These recommendations concern knowledge and science provision in understanding disaster and health-related emergency risks, the extension of disaster risk governance to manage both disaster risks and potential health-emergencies, particularly for humanitarian coordination aspects; and the strengthening of community-level preparedness and response.
This study aimed to describe the natural course of DSM-III-R alcohol disorders as a function of age at first alcohol use and to investigate the influence of early use as a risk factor for progression ...to the development of alcohol disorders, exclusive of the effect of confounding influences.
Data were obtained from a community sample (N=5,856) of lifetime drinkers participating in the 1990-1991 Mental Health Supplement of the Ontario Health Survey.
Survival analyses revealed a rapid progression to alcohol-related harm among those who reported having their first drink at ages 11-14. After 10 years, 13.5% of the subjects who began to drink at ages 11 and 12 met the criteria for a diagnosis of alcohol abuse, and 15.9% had a diagnosis of dependence. Rates for subjects who began to drink at ages 13 and 14 were 13.7% and 9.0%, respectively. In contrast, rates for those who started drinking at ages 19 and older were 2.0% and 1.0%. Unexpectedly, a delay in progression to harm was observed for the youngest drinkers (ages 10 and under). Hazard regression analyses revealed a nonlinear effect of age at first alcohol use, marked by an elevated risk of developing disorders among subjects first using alcohol at ages 11-14.
First use of alcohol at ages 11-14 greatly heightens the risk of progression to the development of alcohol disorders and therefore is a reasonable target for intervention strategies that seek to delay first use as a means of averting problems later in life.
1. Hedgehog plasma was separated by gel filtration on Sephacryl S-200, the fractions resolved by electrophoresis and the electrophoregrams characterized for trypsin, chymotrypsin and elastase ...inhibiting activities with both low and high molecular weight substrates. Approximate molecular weights were also determined. 2. At least ten protease inhibitors were characterized in hedgehog plasma including three macroglobulins. 3. The hedgehog protease inhibitors were identified by immunoelectrophoresis. Four protease inhibitors showed homologies with specific human, rat or swine antisera. These were alpha 2-and beta-macroglobulins, alpha 1-protease inhibitor, and alpha 2-antithrombin.
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