diterpenes from the brown alga dictyota divaricata

Four diterpenes,two of which are new natural products,have been isolated from the brown alga dictyota divaricata,collected from the Great Barrier Reef region of Northern Australia. One is a xenicane derivative,two others are germacranes,while the fourth has a dolabellane type skeleton. The structure of the compounds are proposed on the basis of their spectroscopic data

a diterpene from the marine brown alga dictyota bartayresll

From the dichlorometharic extract of the brown alga Dictyota bartayresii a new diterpene,hydroxypachdictyol A,of the hydroazulenoid type has been isolated and characterized. The structure of the new compound was determined from spectroscopic data

The Effects of Utilizing Social Media Tools During Crisis from Public Relations Practitioners' Views in the UAE

Despite growing interest in social media over the last few years all over the world, there is a lack of empirical studies on the extent to which PR practitioners in the UAE are using social media tools, and in particular, during crisis. Consequently, this study is designed to bridge this gap in research. The study aims to bring to attention the dynamics of using social media among public PR practitioners during crisis in one of the Gulf countries -countries that have different economic, social and political contexts. The current study is considered one of the pioneer studies in the public relations\u27 field in the UAE which aims to investigate how public relations practitioners are using social media tools in crisis. It also explores public relations practitioners\u27 perceptions and attitudes towards using social media during crisis. A random sample of 160 PR practitioners was selected from different public and private organizations in the UAE. The results indicated that PR practitioners are active and heavy social media users in their organizations during crisis. Furthermore, the study confirmed that the most commonly used communication strategies were compensation, corrective action and justification. Additionally, the study suggested that the organization\u27s websites and Twitter were the most effective social media tools used during a crisis

The Newcastles of Clumber A pictorial and documentary history of an important Nottinghamshire family

An exhibition organised by the University Art Gallery and the Dept. of Manuscripts and Special CollectionsAvailable from British Library Document Supply Centre- DSC:q96/04157 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Detection of Misconceptions and Misleading Questions by Using Quantitative Diagnostic Assessment

[[abstract]]Researches into E-Learning pay emphasis on how the technology is applied for comprehensive learning support in various perspectives. Lots of advantages are involved while performing the E-Learning. For example, timely contents are applicable to be delivered via the Internet, and in a similar manner, instant feedback which identifies the learning performance would be obtained through an online assessment system. In this article, a diagnostic approach for learning performance evaluation of student is proposed. Two primary issues are concentrated based on the analysis of quantitative assessment results. First the authors identify the misconceptions on specific subject(s) that students have learned and provide remedial suggestions about their learning status to students. Second, because questions may have several incorrect information to students, hence the authors approach provide suggested revisions to instructors. The proposed approach employs the Rule-Space model and the Student-Problem chart and is implemented in an online assessment system to obtain corresponding data (e.g., learning behavior) and performance (e.g., learning status). The feasibility is demonstrated through an empirical study (i.e., a series of pre-post tests) which was conducted in a domain-specific course (i.e., Fundamental of Information Technology) with around 450 students in a calendar year.[[notice]]補正完