518 research outputs found
Vowel duration in stressed position in central & northern varieties of standard Italian
We report the results of a pilot study investigating the effect of 2 regional accents on stressed vowel duration according to word-position and syllable type in Central v. Northern accents of Standard Italian. While there is overall convergence, we also find significant regional differences in some contexts, i.e. closed syllables, and antepenultimate position. We then consider the implications of our results for the phonological description and phonetic investigation of Italian
Analysis of Flavonoids, Phenolic Compounds and Essential Oils in Curcuma Aerugenosa Roxb. (Zingiberaceae)
Curcuma aerugenosa Roxb. or locally known as “Temu Hitam” has been used as medicine. It contains useful secondary metabolites. The amount of total phenolic content detected in Curcuma aerugenosa is ranged from 4.5 – 50.9 mg pyrogallol equivalent per g dry weight. Leaf and root extracts exhibited strong antioxidant activity in ferric thiocyanate method (FTC), thiobarbituric acid method (TBA), scavenging effect of the 2,2-diphenyl-1-picyl-hydrazyl (DPPH) radical and conjugated diene formation.
In this study, flavonoids and phenolic compounds were determined by using high-performance liquid chromatography (HPLC). The highest content of rutin (1704.7 ± 68.2 μg/g dry weight) and quercetin (1992.4 ± 92.2 μg/g dry weight) were found in leaf unhydrolized and hydrolized extracts respectively. Tuber extract exhibited the highest content of total phenolic compounds (988.6 ± 22.7 μg/g dry weight). The main phenolic compound detected was catechol (615.4 ± 8.2 μg/g dry weight). The essential oils of C. aerugenosa were obtained by hydrodistillation. They were analysed by a gas chromatography mass spectrometry (GC-MS). The major compounds were camphor, 1,8-cineole, β-pinene and camphene. Rhizome oil was found to contain the highest percentage of 1,8-cineole (45.9%) and camphor (15.9%).
In this study, Gamborg B5 media with combination of 0.2 mg/L (w/v) 2,4-dichlorophenoxyacetic acid (2,4-D) and 2.0 mg/L (w/v) 6-benzylaminopurine (BAP) was found as the best for initiation of rhizome bud and in vitro grown seedling-leaf callus. A different combination was obtained in callus induction of in vitro grown seedling-petiole and root which was 0.2 mg/L (w/v) of 2,4-D and 1.0 mg/L (w/v) of 6-furfurylaminopurine (kinetin). The callus induced in this study was friable and light yellow in colour.
Study on the effect of sucrose concentrations [1, 2, 3 and 4% (w/v)] showed that optimum callus growth was achieved with 3% of sucrose. The highest callus growth of in vitro seedling-leaf and root derived callus were achieved in 0.060 and 0.020 mg/L (w/v) of 2,4-D respectively. Both callus produced 6.382 ± 0.408 and 6.440 ± 0.193 g fresh weight /culture respectively. Dicamba [0.150 mg/L (w/v)] produced the highest production of biomass in rhizome bud (5.603 ± 0.263 g fresh weight /culture) and in vitro grown seedling-petiole (5.458 ± 0.246 g fresh weight / culture) derived callus. Elicitors, yeast extract [20, 40, 60, 80 and 100 mg/L (w/v)] and chitosan [20, 30, 40, 50 and 60 mg/L (w/v)] exhibited different effects on monoterpene (1,8-cineole, linalool, β-pinene and camphor) production. The highest content of 1,8-cineole (0.459 ± 0.020 μg/g fresh weight) and camphor (0.067 ± 0.003 μg/g fresh weight) were produced in 40 and 60 mg/L (w/v) yeast extract added to in vitro grown seedling-petiole derived callus respectively. At 50 mg/L (w/v) of chitosan revealed the highest production of linalool (0.374 ± 0.015 μg/g fresh weight) and β-pinene (0.495 ± 0.021 μg/g fresh weight) in vitro grown seedling-petiole derived callus
Spatial and temporal features of hydrodynamics and biogeochemistry in Myponga Reservoir, South Australia.
Understanding hydrodynamic and biogeochemical processes in lakes is fundamentally important to the management of phytoplankton population and the improvement of water quality. Physical processes such as wind-driven surface mixing, thermal stratification and differential heating and cooling can affect the distribution of water, phytoplankton and sediments and the availability of nutrients and light. These lake processes, which are highly variable in space and time, affect phytoplankton dynamics in the field. This study aims to determine the spatial and temporal variability of phytoplankton and processes that either contribute to or override the variability in the artificially mixed Myponga Reservoir, South Australia. A sediment survey showed that sediments underlying deep water were richer in organic matter, carbon, nitrogen and phosphorus than the sediments underlying shallow water. This may lead to different nutrient release rates between the shallow and deep areas. Both sediment resuspension and anoxic sediment nutrient release were important internal sources of nutrient to support phytoplankton growth in summer when external nutrient supplies were limited by low rainfall in the catchment. An analysis of historical water temperature data revealed the development of micro-stratification at the sediment-water interface in summer, especially during a heatwave (air temperature > 40ºC for several consecutive days). Prolonged micro-stratification could potentially induce anoxic layers at the sediment surface, resulting in the release of nutrients. A risk assessment was conducted to predict the release of phosphorus from anoxic sediments and to evaluate the potential impact of cyanobacterial population (Anabaena circinalis) and the release of secondary metabolites (e.g. saxitoxin and geosmin). Spatial variability of surface mixed layer depths exists between the side-arm and main basin. A simple light model based on the relationships of surface mixed layer depth, daily light dose and phytoplankton growth rate, was developed to estimate the potential variation of phytoplankton population in the two different light habitats (the main basin and side-arm). The model showed that phytoplankton abundance in the main basin was lower than in the side-arm. However, differential heating drove a large basin-scale convection, which circulated the water between the side-arm and main basin within hours. This circulation overrode the time scale of days for the light-dependent growth effect between the two sites and hence there was no observable change in phytoplankton community structure. Although no spatial variability of phytoplankton was observed at community level, significant variations of phytoplankton cellular content and stoichiometry were detected. Higher carbon cellular content in the side-arm than in the main basin was probably due to a greater exposure to light (shallower surface mixed layer in the side-arm) for photosynthesis. In the situation where nutrients were scare, higher phosphorus cellular content was found in the side-arm than in the main basin; this was possibly due to a greater exposure to resuspended nutrients from the lake bottom (shallower water in the side-arm). There was also a strong seasonal pattern in phytoplankton cellular content and stoichiometry between summer and early winter of 2009. The carbon content of phytoplankton increased over time, while the phosphorus content decreased. After the first heavy rain event (70 mm over a four-day period) in early May, carbon cellular content decreased, while phosphorus cellular content increased. These changes in phytoplankton contents were most likely related to the bio-availability of phosphorus in water. This study reviews many complex, interactive processes driving the variability of lake physics and chemistry. The variability can yield rapid biological responses at physiological and cellular levels (e.g. Fv:Fm and cellular content), but does not necessarily appear at community levels (e.g. phytoplankton biomass, diversity). Often, conventional monitoring in lakes and reservoirs overlooks the subtle variability of phytoplankton dynamics. The relative scaling among physical, chemical and biological processes, therefore, is important to adequately describe the spatial and temporal variability in lakes and reservoirs.Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 201
Small firm marketing : an analysis of small firm marketing approaches in Hong Kong.
SIGLEAvailable from British Library Document Supply Centre-DSC:DXN014403 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
The Success of an EAP Programme in Tertiary Education: Using a Student-Centric Approach to Scaffold Materials in an EAP
Researchers and practitioners who focus on academic writing in English for Academic Purposes (EAP) courses have reported on the need to equip students with the necessary knowledge and skills to deal with academic writing across different disciplines in tertiary education (Rinnert & Kobayashi, 2005; Shi, 2011; Thompson, 2013). Previous research (e.g., Crosthwaite, 2016) has predominantly measured students’ progress in an EAP by comparing students’ pre- and post-course scores of individual language/writing skills. Much less has been reported on the effectiveness of a detailed EAP curriculum design that scaffolds skills in stages. This study contributes to the current EAP research by examining holistically the impact of a 12-week EAP course that adopts a reading-to-write, student-centric approach to scaffold progressively difficult writing skills/knowledge to help students acquire academic writing skills by focusing on three core skills: language, text organisation, and content development. The data of this study show students’ perceptions of their writing abilities and the significant improvement in academic writing skills before and after completing the course
Efficiency of Digital Technology Use in Schools
Digital technologies in education are increasingly garnering much interest. Teachers and instructors play a fundamental role in ensuring that student-centered learning is the highlight of the application of digital technologies. The research focuses on the efficiency of digital technology in schools, with teachers as a mediating factor. Through the Technological Pedagogical and Content Knowledge (TPACK) framework, teachers\u27 competence and engagement play a critical role in technology application and digital technologies\u27 overall efficiency. In the study, we will conduct a quantitative research on the efficiency of digital technology use in schools
Effect of linguistic context on metaphor comprehension in Cantonese-speaking children
Thesis (B.Sc)--University of Hong Kong, 2009."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, June 30, 2009."Includes bibliographical references (p. 28-30).published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science
Lived Experiences of a Hong Kong Physical Education Teacher: Ethnographical and Phenomenological Approaches
This study employed ethnographical and phenomenological methods to explore the lived experiences and career of a Hong Kong secondary school physical education (PE) teacher (Wharton) in order to embody his versatile roles through phenomenological description of a lived body itself and the lived world. The central research question is “How does a male secondary school PE teacher manage his work life and the embodiment of his professional roles?” Data collection techniques were in-depth interviewing, participant observation and field notes, participant’s reflection documentation and visual elicitation. Concepts of “play to learn,” “professional development” and “political empowerment” were used to examine Wharton’s lived experiences and career. Themes such as Static Gestalt, Dynamic Gestalt, Style Gestalt and Reversibility Gestalt were identified. This study may inform literature on sociological perspectives and the life histories of PE teachers and applicable to other teachers as they adapt to environmental changes in other settings
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