What Do Dental Students Think About Mandatory Laptop Programs?

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153745/1/jddj002203372006705tb04103x.pd

Electronic Curriculum Implementation at North American Dental Schools

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153722/1/jddj0022033720046810tb03851x.pd

The Population Genetics of Balanophora fungosa (Balanophoraceae) in Taiwan

粗穗蛇菰（Balanophora fungosa）為根部完全寄生植物，且為台灣稀有植物之一。本物種生長於恆春與蘭嶼，族群分布不連續，且二地區間之花序顏色有明顯差異。本研究利用簡單重複序列間區分子標記法，對該物種進行族群遺傳研究初步探討，試圖了解地區間與族群間之分化程度。以7個引子透過聚合酶連鎖增幅基因組DNA，共產生250個條帶，具有遺傳變異之多型性條帶佔75.20 ％。分子變異分析顯示遺傳變異主要集中於族群內，其變方成分百分比佔整體的54.91 ％。不加權平均法（UPGMA）運算獲得之Dice相似度樹狀圖結果，顯示粗穗蛇菰之樣本群依照恆春與蘭嶼地區劃分為二，地區間相似度0.78，變方成分佔31.35 ﹪；地區內之不同粗穗蛇菰族群則略有分化，佔有13.74 ﹪變方成分，可能因族群分布不連續，使族群間基因交流受阻所致。不同族群間以墾丁公園族群與小天池2族群之分化程度最大，其族群間Φst遺傳距離高達0.5264。透過POPGENE軟體分析，顯示粗穗蛇菰之遺傳分化係數（GST）為0.3016，大於其他異株授粉之風媒花與蟲媒花之平均值，推測本物種之有性生殖偏向以自交為主。而物種總遺傳歧異度僅為0.1730，低於其他自交物種之平均值，顯示其基因庫變異較不足。而本研究物種族群樣本數量不足，所得之基因交流數値（Nm）易有偏估，故本研究暫對由POPGENE獲得之Nm値持保留態度。Balanophora fungosa is a rare root-holoparasitic species in Taiwan, mainly distributed in Heng-chun and Lan-Yu regions. The populations are disjunctive, and colors of the inflorescences differ among populations from the two regions. This study would aims at the population genetics of B. fungosa in Taiwan using ISSR markers to understand the degree of differentiation among populations and between regions. Seven primers were uesd, resulting in 250 bands across a total of 40 individuals, and the percentage of polymorphic loci was 75.20 % at the species level. The results of AMOVA revealed that genetic variances were occurred mainly within populations about 54.91 %. The UPGMA tree showed two clusters representing Heng-chun and Lan-Yu regions, respectively. Dice similarity between two clusters was 0.78, and contributing 31.35 % of total variances. The populations within regions included 13.74 % of total variance, which showed slight differentiation. Such a differentiation might arise from interfered gene flow among isolated populations.The maximal Φst genetic distance value of populations by pairwise comparison was 0.5264, occurring between Kenting Park and Hsiaotienchih-2. In POPGENE analysis, the GST value of B. fungosa was 0.3016, higher than the average value of insect- and wind-pollinated species, suggesting that it is probably self-pollinated mainly like geitonogamy. The total genetic diversity at specise level was 0.1730, lower than the average value of self-pollinated species, revealing that the diversity of B. fungosa gene pool is low. Because of deficient sample size, the gene flow value (Nm) might be mis-estimated, that relevant conclusion is tentatively reserved.中文摘要------------------------------------------------------------------------------------1 英文摘要------------------------------------------------------------------------------------2 壹 前言------------------------------------------------------------------------------------4 貳 前人研究------------------------------------------------------------------------------6 參 材料與方法-------------------------------------------------------------------------17 肆 結果----------------------------------------------------------------------------------25 伍 討論----------------------------------------------------------------------------------29 陸 參考文獻----------------------------------------------------------------------------39 柒 表格與圖片 表格----------------------------------------------------------------------------47 圖片----------------------------------------------------------------------------51 捌 附錄 樣本之條帶模式----------------------------------------------------------5