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191.
192.
This article seeks to explore how the BBC made sense of the al-Qaeda phenomenon in its flagship “News at Ten” bulletin during the aftermath of the September 11th 2001 attacks. Using Critical Multimodal Discourse Analysis, it shows how the BBC’s representations function as a dynamic and continually shifting site upon which a range of fears, identities, discourses and forms of knowledge and power struggle and contend, and through which a number of different “al-Qaedas” manifest themselves. In particular, three shifting modes of visual and verbal representation are identified within the BBC’s coverage which each correspond to a separate understanding of al-Qaeda: the “Islamic” mode, the “Personalised” mode and the “Elusive” mode. These representations both draw upon and challenge the dominant discourses surrounding Islam, non-state terrorism and the identities of terrorist suspects, providing audiences with a variety of often conflicting ways of seeing and speaking about this entity. As such, the article provides insight into the complex nature of the BBC’s representations of al-Qaeda during its coverage of the September 11th 2001 attacks, and shows how such complexity serves, albeit inadvertently, to legitimise the far-reaching counterterrorism policies that were enacted in the aftermath of these attacks.  相似文献   
193.
The recent increase in the number of students classified as English language learners (ELLs) has focused significant attention on reclassification policy, which governs the process by which ELLs move toward, and are deemed to reach, full English proficiency. In this paper, we draw on a data set containing annual individual‐level records for every Wisconsin student ever classified as an ELL between the 2006–07 and 2012–13 school years to estimate the effects of being reclassified at the end of 10th grade—a crucial period on the pathway to postsecondary education—on several measures related to students’ postsecondary attainments. We estimate these effects in a regression discontinuity framework, exploiting Wisconsin's policy rule that automatically reclassifies ELLs who score above a specified cutoff on the state's English language proficiency exam. Our analysis indicates that being reclassified as fully English proficient in 10th grade has a positive effect on students’ ACT scores. It also provides some evidence of a positive effect on high school graduation and the probability of enrolling in a postsecondary institution the fall after graduation. Together, our analyses provide evidence on the effects of a policy directly relevant to the country's fastest growing student population, and we close the paper with a discussion of the implications for research and policy.  相似文献   
194.
Fifty-three head hair specimens were collected from 38 males with a history of cannabis use documented by questionnaire, urinalysis and controlled, double blind administration of delta9-tetrahydrocannabinol (THC) in an institutional review board approved protocol. The subjects completed a questionnaire indicating daily cannabis use (N=18) or non-daily use, i.e. one to five cannabis cigarettes per week (N=20). Drug use was also documented by a positive cannabinoid urinalysis, a hair specimen was collected from each subject and they were admitted to a closed research unit. Additional hair specimens were collected following smoking of two 2.7% THC cigarettes (N=13) or multiple oral doses totaling 116 mg THC (N=2). Cannabinoid concentrations in all hair specimens were determined by ELISA and GCMSMS. Pre- and post-dose detection rates did not differ statistically, therefore, all 53 specimens were considered as one group for further comparisons. Nineteen specimens (36%) had no detectable THC or 11-nor-9-carboxy-THC (THCCOOH) at the GCMSMS limits of quantification (LOQ) of 1.0 and 0.1 pg/mg hair, respectively. Two specimens (3.8%) had measurable THC only, 14 (26%) THCCOOH only, and 18 (34%) both cannabinoids. Detection rates were significantly different (p<0.05, Fishers' exact test) between daily cannabis users (85%) and non-daily users (52%). There was no difference in detection rates between African-American and Caucasian subjects (p>0.3, Fisher's exact test). For specimens with detectable cannabinoids, concentrations ranged from 3.4 to >100 pg THC/mg and 0.10 to 7.3 pg THCCOOH/mg hair. THC and THCCOOH concentrations were positively correlated (r=0.38, p<0.01, Pearson's product moment correlation). Using an immunoassay cutoff concentration of 5 pg THC equiv./mg hair, 83% of specimens that screened positive were confirmed by GCMSMS at a cutoff concentration of 0.1 pg THCCOOH/mg hair.  相似文献   
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