Wadi Arar in the Northern border region of Saudi Arabia is one of the most important Wadis of the Kingdom. The present study provides an analysis of vegetation types, life forms, as well as floristic categories and species distribution. A total of 196 species representing 31 families of vascular plants were recorded. Compositae, Gramineae and Leguminosae were the most common families. Therophytes and chamaephytes are the most frequent life forms, indicating typical desert spectrum vegetation. The distribution of these species in the different sectors of the Wadi as well as the phytochoria for the recorded species is provided. Ninety-one species (46.5%) are typical bi-regional. Furthermore, about 105 species (53.5%) are mono- or pluriregional taxa. The highest number of species (136 or 69.5%) was recorded for annual plants, while the lowest number of species (60% or 30.5%) was recorded for perennial, short perennial or annual to biennial species.
Four species of the genus Artemisia L. (Artemisia monosperma, Artemisia scoparia, Artemisia judaica and Artemisia sieberi) growing in the northern region of Saudi Arabia were investigated with respect to their volatile oil contents. The yield of oil varied between 0.30 and 0.41%, % (w/w). A. monosperma showed the highest number of compounds with 30 components representing 93.78% of oil composition. However, A. judaica showed the lowest number of compounds with only 16 components representing 87.47% of essential oil. A. scoparia and A. sieberi are both composed of 17 components, representing 97.14 and 94.2% of total oil composition. A. sieberi and A. judaica were dominated by spathulenol (30.42 and 28.41%, respectively). For A. monosperma, butanoic acid (17.87%) was a major component. However, A. scoparia was a chemotype of acenaphthene. (83.23%). Essential oil of studied species showed high antibacterial activities against common human pathogens.
This study reports on and investigates an institutionalized remedial approach held by an English language institute (ELI) at a Saudi University in order to support foundation year struggling students who often achieve low grades or fail to pass a certain level of the English language program. The study utilizes semi-structured interviews to address three issues: (1) Screening for low-achieving learners; (2) Remedial sessions" procedure and significance; (3) Learners" attitudes and conduct during remedial sessions. Thematic analysis of interviews with teachers shows that time limitation and lack of logistical structure lower the effectiveness of remedial sessions in terms of numbers of supported learners and the remedial procedure itself. It was also found that class teachers" role is often lacking in this case-study. Low-achieving learners are rarely referred by their teachers, but instead come on their own to seek support. However, this optional nature of the process resulted in remedial sessions receiving learners who are self-motivated, have positive attitude, and exhibit different classroom conduct than students in the mainstream classes. Furthermore, the analysis yields other findings related to the usefulness and significance of remedial intervention. Learners were found to seek remedial support for two main reasons: supportive environment and simplified instruction. Much of this can be addressed in regular classrooms. The study concludes with other implications for remedial sessions" logistics and practices, as well as for the teaching/learning process of low-achievers.
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