殊途同歸-格子點平面最短路徑和之探討
本研究從理想城鎮(Ideal City)街道開始,討論平面上相異n 點到某一點的最短距離和。經研究後發現:當n 為偶數時,則到相異n 點的最短距離和所形成的區域可能是一個點、一個線段或是一個矩形;當n 為奇數時,則相異n 點的最短距離和所形成的區域將會退化成一個點。此外,本研究將理想城鎮的街道換成正三角形的街道幾何平面,同樣是討論平面上相異n 點到某一點的最短距離和。經研究後發現:當n 為偶數時,則相異n 點的最短距離和所形成的區域可能為一個點、一個線段、一個四邊形、一個五邊形及一個六邊形;當n 為奇數時,相異n 點的最短距離和所形成的區域則可能為點、三角形的情況。假使考量各點重要性的比重,分別加權後再求最小點。研究發現無論在理想城鎮或正三角形幾何平面上,皆可將各點視為多個權數相同之點重疊於此點上,便可利用先前的方式求得最小點區域。透過這次的研究,可以利用n 個相異點到某一點的最短距離和實際應用在貨物運送的問題或是消防設施配置等問題。The present study was intended to start with the Ideal City and proceed to discuss the sum of the shortest distance between a point and n different points on a plane. After the discussion, it was found that if n is even, the formed region could be a point, a line segment, or a rectangle. If n is odd, then the formed region must be a mere point. Further, the current study transformed the Ideal City into the geometric plane of an equilateral triangle. Similar to the previous discussion, if n is even, the formed region could be a point, a line segment, a quadrangle, a pentagon, or a hexagon. On the other hand, if n is odd, then the formed region could be a point, or a triangle. The result of this study, which investigated the sum of the shortest distance of a certain point to n different points can be applied to the real life situation, such as transporting goods or distributing fire control facilities.
光子晶體合成、特性與應用
We report an investigation on the synthesis, characterization, and application of photonic crystal. In the study of the synthesis of SiO? nanoparticles for the building blocks of photonic crystal, it is found that by changing the concentration of NH3 solution, we are able to control the size of SiO? nanoparticles. After trying several different methods, we discover that the vertical substrate method is the best way to arrange nanoparticles into a periodic structure. From scanning electron microscope, we confirm that SiO? nanoparticles can form a three dimensional hexagonal photonic crystal. From transmission experiment, we find that the wavelength of the minimum transmission is proportional to the size of nanoparticles. This result implies that using photonic crystals we can control the behavior of electromagnetic wave. Finally, we fabricate CdS nanoparticles on the top of photonic crystals with different diameter of SiO? nanoparticles. Using photoluminescence measurements, we show that by controlling the lattice constant of a photonic crystal the luminescent efficiency of CdS nanoparticles can be substantially enhanced. Out results, therefore demonstrate that photonic crystals are very important for the application of light emitting devices. 本研究主要是著重於探討光子晶體合成、特性分析及其應用。在有關合成光子晶體之奈米二氧化矽顆粒方面, 發現在合成過程中利用氨水的溶量可以控制顆粒的大小。在將奈米顆粒排列成光子晶體的研究中, 嘗試了多種方法後, 發現垂直基座法為最快速有效的方法。從掃瞄電子顯微鏡的觀測, 證實奈米顆粒是以六角對稱排列成整齊的光子晶體。在光子晶體的特性分析中, 利用光穿透實驗, 發現電磁波穿透率最小的波長與奈米顆粒成正比關係, 這顯示出可以利用光子晶體來控制光的行為。最後,本研究將光子晶體與硫化鎘奈米顆粒結合,經由光激螢光譜, 證明光子晶體確實可以增進物體之發光效率,這對發光元件的應用, 將有很大的幫助, 可以節省大量的能源
大安水蓑衣(Hygrophila pogonocalyx)的復育對黑擬蛺蝶(Junonia iphita iphita)食性偏好??
大安水蓑衣(Hygrophila pogonocalyx)為局限分佈於臺中縣沿海溼地之稀有植物。大量境外復育栽殖後,造成近年來黑擬蛺蝶(Junonia iphita iphita)利用此種新寄主植物的比例增加。本實驗比較黑擬蛺蝶在原寄主植物臺灣馬藍(Strobilanthes formosanus)及新寄主植物大安水蓑衣上之生長環境遮蔽度、幼蟲生長發育、雌蝶產卵偏好的差異,探討大安水蓑衣復育對黑擬蛺蝶族群可能造成的影響。實驗結果發現利用大安水蓑衣之幼蟲生長發育較佳、羽化後成蟲體型較大、有效積溫常數較低。雌蝶產卵行為可能存在兩種偏好性,且子代雌蝶對寄主植物的偏好性與親代一致,不受幼蟲期取食植物影響。偏好新寄主植物之雌蝶其子代的生長發育,利用新寄主植物者顯著較利用原寄主植物者佳,顯示其對原寄主植物的適應顯著下降。本研究認為大安水蓑衣的復育結果,造成黑擬蛺蝶族群在可能共域的情況下,因為利用新的寄主植物可能已產生初步分化的現象。Hypgrophila pogonocalyx is a rare plant species which is distributed in wetlands along seashore of Taichung County. Recently, I found that the common butterfly Junonia iphita iphita recognized H. pogonocalyx as a new hostplant because of the restoration practices of H. pogonocalyx. We compared the differences of forest overstory coverage, larval growth performance and female oviposition preference between J. iphita iphita individuals exploiting the H. pogonocalyx and those utilizing the original hostplant Strobilanthes formosanus. Possible effects on J. iphita iphita by restoration of H. pogonocalyx are analyzed and discussed. It turns out that better growing performance and longer adult forewing length were found on the larvae feeding on H. pogonocalyx than those on the S. formosanus. Besides, the larvae feeding on H. pogonocalyx demonstrated lower constant value of effective accumulated temperature, suggesting that the new host may provide more energy to the larvae than the original host does. Two types of female oviposition preference seem to exist. No matter which hostplant the larvae fed on, the female adults still maintained the oviposition preference of the parental generation. Offspring of H. pogonocalyx-preferring female had better performance on this new hostplant. Our studies showed that the restoration of H. pogonocalyx might have caused primary differentiation of J. iphita iphita by using new hostplant in sympatry with the original hostplant.
阿拉伯芥AtYAK1 基因5'UTR 中的開放讀序框(uORFs)對基因表現調控之探討
在模式植物──阿拉伯芥(Arabidopsis thaliana)中,AtYAK1(Arabidopsis thaliana Yak1-related protein kinase)是目前發現唯一屬於DYRK(Dual specificity Yak1-Related protein Kinase)的蛋白激?。雖然之前研究已證明,不同物種之DYRKs 和細胞的生長與發育過程有關。然而,其在植物中的生理功能卻尚未被明確地研究報導過。在先前的研究中,為瞭解AtYAK1 在阿拉伯芥內作用之位置,前人選取AtYAK1 基因ATG 上游約2.5 kb 的序列(Upstream Element, 2.5KUSE)建構至一含有GUS(β-glucuronidase)報告基因的質體中,並轉形至阿拉伯芥,進行GUS 組織染色分析。但在初步結果中,並沒有在轉殖株觀察到明顯的GUS 表現。進一步分析,我們發現在2.5KUSE 序列末端約0.5 kb 的5’非轉譯區(5’untranslated region, 5’UTR)中,有四組開放讀序框(Upstream Open Reading Frame, uORF)。有趣的是,許多研究也顯示,uORFs 會影響轉譯過程中的再起始(re-initiation)作用而調控該基因的表現。另一方面,前人亦透過構築好的2KUSE 轉殖株(即不含有5’UTR)進行上述GUS 實驗。結果發現,此2KUSE 轉殖株的GUS 表現非常顯著。本實驗即要瞭解AtYAK1 的uORFs 是否也會影響其蛋白質的合成。首先,我們以點突變的方式將四組uORFs 中之ATG 換成TTG,目的為構築不含有uORFs 之5’UTR(mutated uORFs, ΔuORFs)。在進行原生質體短暫表現分析法(protoplast transient assay)及GUS 組織染色分析後,將結果與含有uORFs 的結果作比較:當缺乏uORFs 後,其3’端報告基因的表現量確實比原來顯著。綜合以上,我們認為此uORFs 對於AtYAK1 蛋白質之表現佔有相當重要的影響地位。最後,我們對5’非轉譯區是否存在開放讀序框進行阿拉伯芥全基因組分析,相關結果亦於本研究報告中分析討論。AtYAK1(Arabidopsis thaliana Yak1-related protein kinase)is the first DYRK(Dual specificity Yak1-Related protein Kinase ) family member identified in the model plant ─ Arabidopsis thaliana and exists as one copy gene in Arabidopsis. Previous studies showed that many eukaryotic DYRKs are involved in regulating the growth and development of cells. However, the study of AtYAK1 in Arabidopsis is lacking to date. In order to understand where AtYAK1 expresses and functions in plants, a 2.5 kb fragment which is located upstream from the major ATG of AtYAK1(termed Upstream Element, 2.5KUSE)was previously constructed to drive the expression of a reporter gene, GUS(β-glucuronidase), in transgenic Arabidopsis. Much to our surprise, no GUS expression signal could be detected in such transgenic plants. When further analyses were performed, we found that there are four upstream open reading frames (uORFs) in the 5’untranslated region ( 5’UTR ) within the 2.5KUSE. Many studies indicating that the uORFs can regulate the translation of downstream ORF encoding the major gene product through the procedure of translation re-initiation. This action represents a mode of translational regulation for gene expression. Indeed, GUS activity could be readily detected in transgenic plants expression 2KUSE::GUS, a construct lacking the 5’UTR of AtYAK1. In this study, I have tried to elucidate whether the uORFs of AtYAK1 can regulate the translation of the downstream major ORF. First, in order to construct a 5’UTR fragment of which uORFs have been mutated(ΔuORFs), we apply site-directed mutagenesis to substitute ATG with TTG for the four uORFs and examine the expression of GUS driven by this mutated 2.5KUSE. After analyzing the results in both Arabidopsis protoplast transient assay and transgenic Arabidopsis, stronger expression of reporter genes in both systems were observed when the four uORFs were mutated. We have also confirmed that, in transient expression system, the increase of reporter gene activity was not due to the excess accumulation of the corresponding mRNAs. Rather, it is the four uORFs which play an important role in negatively regulating the translation of AtYAK1, possibly via inhibiting the translation re-initiation of major ORF. A genome-wide examination of uORFs in all Arabidopsis genes was also performed to assess the possible contribution of uORF in regulating gene expression.
湖光山色下的哀愁--由漂浮的琵琶鼠魚探討外來入侵種與放生行為
本研究自2005 年12 月開始,以臺北市內湖區大湖自公園死亡的漂浮琵琶鼠魚(Many-rayed Sailfin Sucker Catfish )為主要研究對象,探討外來物種與放生行為對大湖生態系的影響。 研究期間共觀察到死亡的琵琶鼠魚隻數計有1085 隻,可記錄到個體形質資料的隻數為910 隻,背鰭棘數則有11 棘、12 棘、13 棘與14 棘四種,分析四種不同棘數的琵琶鼠魚後發現:在體長、頭寬及吻到背鰭長度均無差異(p>0.05),因此判斷所記錄的個體應是棘甲鯰科(Loricariidae) Pterygoplichthys 屬中的同一種魚種。由檢視魚體並分析記錄數量與環境因子相關性後推測:琵琶鼠魚死亡主因是劇烈起伏的溫度差異,其次是人為因素的刻意傷害。 所記錄到大湖池塘水棲動物有:環節動物、軟體動物、節肢動物、魚類、兩棲動物及爬行動物等六大類共34 種,其中外來物種有16 種,本地入侵物種有3 種,而這些外來動物進入大湖的主要管道應是由個人的棄養或放生行為所造成。琵琶鼠魚因繁殖能力強、具攻擊性、吞食其他魚種卵塊、可適應高污染水體及垂釣客對魚種的篩選等因素,而成為最具生存競爭能力的優勢魚種。不但造成大湖池塘呈現嚴重魚種單一化,更可由靜止水域大量擴散至流動水域。未來如何將政府相關部門、學術研究單位與民間社團等力量結合,共同防範大湖琵琶鼠魚的持續蔓延、宣導民眾正確的放生觀念、積極改善大湖水體污染狀況,並訂定完整之外來物種移除計畫,以期恢復大湖池塘物種歧異度,都將是刻不容緩的重要生態課題。;This research began in December of 2005. Focusing on dead floating Many-rayed Sailfin Sucker Catfish in Dahu Park, Nei-hu Distrct, Taipei city. We discuss the impacts of Alien and of behaviors of the release of captured animals on Dahu Park’s ecosystem. During observation period, there were totally 1085 dead Many-rayed Sailfin Sucker Catfish, of which 910 bodies were found. The number of the thorn bushes on dorsal fins includes 11, 12, 13,and 14. After analyzing four kinds of different thorn bushes, we find that no differences exist in Total length, Head width, Predorsal length (p>0.05). We hence conclude that the recorded object should be species with identical with Loricariidae Pterygoplichthys. With the inspection of the fish’s body and the analysis of the relevance of the recorded quantity and the environmental factor, we infer that the main reason of the Many-rayed Sailfin Sucker Catfish’s death is violent temperature differences and the second is attributed to human’s intentional abuse. The aquatic animals of Dahu Park amount to 34 kinds and six classes such as Annelida, Mollusca, Arthropoda, Pisces, Amphobian, and Reptilia. Among them, 16 kinds that are Alien and 3 kinds are Native Invasive Species. Intentional abandon and release behavior channel of these Alien to Dahu Park. Many-rayed Sailfin Sucker Catfish are highly productive, aggressive, and adaptable to highly polluted water. Besides, they eat ovums from other fishes. Moreover, they are not the fisher’s preference and hence often thrown back into pond once hooked . Thus, they become the most competitive survival fish species in Dahu Park. The high competitive ability of Many-rayed Sailfin Sucker Catfish causes Dahu Park to present a serious unification of fish species. This serious unification of fish species could also be spread from static water areas of Dahu Park to flowing water areas. According to our research, certain urgent ecological issues in Dahu Park are to take precautions against the spread of Many-rayed Sailfin Sucker Catfish, to promote the correct idea of releasing captured animals, to improve Dahu Park’s water pollution, and to stipulate a complete plan about eliminating Alien. Our research suggest that government’s relevant departments, academic research units, and folk corporations should be cooperated to achieve the above four goals. Once the four goals are achieved, we believe that the fish species of Dahu Park will be full of varieties again.