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In vitro evidence of cellular adaptation to ozone toxicity in the rat trachea.
Adaptation to prolonged ozone (O3) exposure occurs in the tracheal epithelium of rats and is marked by the presence of ciliated cells with uniform short cilia but is not accompanied by shifts in cell populations, altered characteristics of epithelial secretory cell products, increased cell turnover, or elevated tracheal superoxide dismutase activity. The purpose of this study was to test the hypothesis that adaptation is a result of alterations intrinsic to epithelial cells or to the cells and their matrix, and not due to systemic or neural influences. Rats were preexposed to either filtered air (FA) or 0.96 ppm O3 for 8 hr/night for 60 days, and then their tracheae were removed and exposed to 3 ppm O3 in an explant culture system where behavioral, nasal, exudative, and secretory product influences can be eliminated. After exposure to 3 ppm O3 in vitro, quantitative electron microscopic evaluation demonstrated that the epithelia from the FA preexposure group had significantly more necrotic cells and sloughed cells and fewer ciliated cells than the epithelia from the O3 preexposure group. Thus previous exposure to ozone in vivo induces a change in tracheal epithelium which confers resistance to ozone-induced injury in the explant exposure system
Iron Age and Roman copper alloys from northern Britain.
SIGLEAvailable from British Library Document Supply Centre- DSC:DX185540 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Analysis of Benefits to Young Rail Enthusiasts of Participating in Extracurricular Academic Activities.
The paper examines a number of positive academic outcomes achieved by university students who, as young rail enthusiasts representing over 10 European institutions, took part in extracurricular rail-related academic activities. Analyses presented in the paper are based on the evaluation of the responses to the questionnaire distributed amongst participants of three consecutive editions of an intensive program in rail and logistics which took place in 2012, 2013, and 2014. Also, quotes from follow-up one-to-one interviews with participants are used to support the results presented. The sample for each year varies in terms of numbers, nationalities, academic backgrounds, and male:female ratio. Academic benefits are specifically looked into, which includes teaching and learning activities throughout the three weeks of the program. The analysis of results revealed that young rail enthusiasts who participated in the program benefited from lectures delivered in Week 1, especially those focused on multimodal transport and rail infrastructure in 2013, which received positive mean ratings of 4.45 and 4.53, respectively, on a five-point Likert scale. Moreover, academic benefits were strongly supported by non-technical skills improvements in areas such as English language and communication, both reaching the mean ratings of 4.35 or above in 2014. A number of recommendations for improvements of next editions of similar rail-related programs as well as areas for future research are identified in the paper
Clinical findings, rhinoscopy and histological evaluation of 54 dogs with chronic nasal disease
Nasal diseases are very common in dogs and rhinoscopy is often required for a definitive diagnosis. Rhinoscopy, while superficial in nature, can guide the clinician to the final diagnosis. In this study, rhinoscopy was performed on 54 dogs with symptoms of chronic nasopharyngeal disease. The endoscopic diagnosis of neoplasia or chronic nasal inflammation was validated with histological examination of pathological samples, in order to evaluate the degree of concordance between endoscopic findings and histological diagnosis. The agreement between endoscopy and histology was tested by application of Cohen's kappa coefficient. We conclude that correlation between endoscopic results and histological diagnosis, expressed by a Cohen's kappa coefficient of 0.73, is only possible with a constant cooperation between the clinician and the pathologist
Readers building fictional worlds:visual representations, poetry, and cognition
This article explores the complex nature of the literature classroom by drawing on the cognitive linguistic framework Text World Theory to examine the teacher’s role as facilitator and mediator of reading. Specifically, the article looks at how one teacher used visual representations as a way of allowing students to engage in a more personal and less teacher-driven transaction with a poem, and to encourage them to reflect on their own roles as active makers of meaning and knowledge in the classroom. The article shows how teachers can be mindful of the various contextual factors that can privilege and legitimise certain kinds of response in the classroom and be wary of external factors and pressures that can promote the idea of preconceived knowledge. The teacher in the case study presented was able to both facilitate the experience of reading poetry in an unmediated way and also develop her students’ metacognition in relation to the reading process itself. The article shows how Text World Theory’s status as a socio-cognitive grammar may be of benefit to teachers in understanding the nature of communicative interaction and literary transaction
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