To unravel the roles of soluble acid invertase in muskmelon (Cucumis melo L.), its activity in transgenic muskmelon plants was reduced by an antisense approach. For this purpose, a 1038 bp cDNA fragment of muskmelon soluble acid invertase was expressed in antisense orientation behind the 35S promoter of the cauliflower mosaic virus. The phenotype of the antisense plants clearly differed from that of control plants. The transgenic plant leaves were markedly smaller, and the stems were obviously thinner. Transmission electron microscopy revealed that degradation of the chloroplast membrane occurred in transgenic leaves and the number of grana in the chloroplast was significantly reduced, suggesting that the slow growth and weaker phenotype of the transgenic plants may be due to damage to the chloroplast ultrastructure, which in turn resulted in a decrease in net photosynthetic rate. The sucrose concentration increased and levels of acid invertase decreased in transgenic fruit, and the fruit size was 60% smaller than that of the control. In addition, transgenic fruit reached full-slip at 25 d after pollination (DAP), approximately 5 d before the control fruit (full-slip at 30 DAP), and this accelerated maturity correlated with a dramatic elevation of ethylene production at the later stages of fruit development. Together, these results suggest that soluble acid invertase not only plays an important role during muskmelon plant and fruit development but also controls the sucrose content in muskmelon fruit.

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Chinese students learning English as a foreign language seem to get good marks in tests, but are poor or limited in their ability to write in English. This dilemma of China's EFL writing instruction seems to be related to the decontextualized EFL writing practices. This study aims to examine how Chinese EFL college students respond to changes in their writing instruction that pays attention to the context of EFL teaching and learning. In this study, context refers to three levels: linguistic context, situational context and cultural context. Using the mixed methods approach, I conducted the study by engaging 60 secondyear undergraduate students from a university in China and five Chinese students studying in a joint program in a university in the United States. The Write-to-learn Model based on my context-oriented framework was used in the study. The findings of the study show that following a 5-month training with the Write-tolearn Model, the experimental group improved significantly more than the control group with respect to English writing, indicating that adding context to EFL teaching and learning created positive writing outcomes for EFL students. In addition, the results of this study also demonstrate that the Chinglish phenomenon was related to decontextualized EFL writing practices and thought patterns resulting from culture. Adequate comprehensible input of authentic materials was found to be a good remedy to minimize EFL students' Chinglish expressions. This study found that the Write-to-learn Model was an effective approach in China's EFL writing classes. Along the journey of my EdD studies at the Graduate School of Education, Portland State University, I have been supported, encouraged, and inspired by many people. Without your help, it would have been impossible for me to complete the program. My first acknowledgements go to four prestigious professors from the Portland State University. I am very much indebted to my advisor, Dr. Yer Thao, who has generously offered your expertise, wisdom, and continuous encouragement in guiding me and mentoring me step by step through the whole research process. I am eternally grateful to Dr. Stevens, whose profound knowledge, intelligent questions on every committee meeting, and passionate love for academic work has always been an inspiration for me. I would also like to give my sincere and deep gratitude to Dr. Henry, for your careful reading of every version of my thesis and for your wonderful lectures, which broadened my horizons in terms of politics and education policy. I am also thankful to Dr. Carstens for your constructive remarks in leading me to take a critical perspective on the literature reviewed, the research methodology and data analysis. I wish to thank Prof. Lu Shen for the great help and support you gave to Sub-study 1 conducted in a university in China. Your insightful comments and suggestions are greatly appreciated. I'm also appreciative of Dr. Chuming Wang for your everlasting encouragement and strong faith in my becoming a scholar. I have b...

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