榕樹粗萃取液對種子萌發及生長之影響
相剋作用是指植物在代謝過程中釋放出有毒物質以抑制本身或鄰近植物種子萌發及植株發育生長的過程。一般認為，榕樹是具有相剋作用的常見植物，但很少見到相關的文獻探討。本實驗利用榕樹不同組織萃取液，以小白菜、結球白菜與阿拉伯芥作材料，探討該萃取液對上述植物發芽與生長之影響，結果顯示榕樹葉萃取液所造成之影響較顯著，不同榕樹組織的萃取液、不同濃度的萃取液對不同植物所產生的效果不盡相同，針對不同生長期的植物進行處理所造成的影響亦有差異。進一步以管柱層析法與高壓液相層析法（HPLC）分離葉萃取液，結果發現以正己烷和乙酸乙酯75：25為沖提液的條件下，於HPLC的層析圖中分離時間約8分時所流出的物質具最明顯的抑制作用。電泳剖面分析顯示處理與未處理間有些許蛋白質條帶差異，此變化蛋白可能與植物幼苗對該萃取液之耐受性有關。利用核酸微陣列(microarray)對榕樹萃取液處理之阿拉伯芥植物進行基因表現分析，發現榕樹萃取液對植物部分基因表現也有促進和抑制的情形，經由基因體與蛋白質體分析法可推論出一些受影響之相關基因。 Allelopathy was defined as a phenomenon which certain plant species, by secreting metabolites to the environment, can suppress the growth of themselves, seed germination and/or growth of other plants in the same habitats. Banyan （Ficus microcarpa L.f.） is a plant species in our campus likely to have allelopathy effect. However, documents describing such action on allelopathy were rare. In this study, we applied the crude tissue extracts including leaves, stems, roots of banyan onto the germinating seeds of Pai-Tsai （Brassica rapa L.ssp.chinensis（Rupr.（Olsson）））, Chinese cabbage （Brassica pekinensis Rupr.） and Arabidopsis（Arabidopsis thaliana, ecotype Columbia-0） to study the effects of such plant extract on the germination and seedling growth of other plants. It is found that allelopathic effects on seed germination vary among different tissues used for extract preparation. Different concentration of the extract also yield various degree of allelophathic effects. It is also noted that the application of extract onto the post-germinated sprouts has less effects on plant growth. The extract of leaves was subsequently chromatographed over silica gel using hexane/EtOH gradient solvent system and HPLC. The result showed that there was one fraction about 8 min in the chromatography of HPLC eluted with 25% EtOAc in hexane had the most inhibitory effect. SDS-PAGE analysis on the electrophoretic profiles of water soluble proteins has explored a different band pattern between the treated and non-treated sprouts. The observed band difference might provide a clue for exploring proteins which reacted differently upon the application of extract. DNA microarray analysis on the effect of banyan extract on Arabidopsis gene expression has also been employed to characterize genes responsive to the allelophathic treatment. Cross-comparison between the differential transcript and protein profiles will reveal key regulators in plants experiencing allelophathic condition. \r
蟋蟀的聲音分析與聲音行為探討
蟋蟀聲音與行為的關係密不可分。取北部四種蟋蟀樣本，以數位錄音筆錄製及電腦軟體分析蟋蟀的聲音，並用PCR技術萃取蟋蟀的粒線體DNA(16S)加以分析，藉此和傳統的形態學分類相互比較。結果發現蟋蟀聲音的頻率特性中主頻率的差異在親緣遠近有關聯性，但聲音的時間特性方面則沒有特定關聯，不過聲學分析圖仍可作為單一種的鑑定指標。此外，研究發現此4種蟋蟀的聲音頻率範圍有重疊現象，但主頻率、脈衝比、唧聲率及唧聲長不同，推測雌蟋蟀應是綜合這些特性辨別同種。另一方面，以黑蟋蟀作為研究對象，進行干擾實驗，觀察並繪製出其聲音行為模式; 並將此作為對照，結果發現蟋蟀的生殖行為主要受到雄蟋蟀的聲音支配，而雄蟋蟀則以嗅覺辨別雌蟋蟀位置，決定下一步行動，與視覺較無關係。 Cricket's voice is closely related to the behavior. We select four species of crickets from the northern Taiwan to study the acoustic and mating behaviors. The digital sound recorder and acoustic software are used to analyze their acoustic characters. Furthermore, the PCR technology is used to amplify and sequence parts of mtDNA sequences and the results were compiled as the comparison to the traditional morphological character. The result shows that the resolution in acoustic characters of main frequency, pulse number, chirp rate, and the length of chirp are different among four species, though the minor frequency pattern is overlapping. Moreover, we find that frequency characteristic difference among four species is partly related to their phylogenetic relationship, yet is not seen in time characteristic. It is obvious that difference of acoustic behavior can be regarded as identified index among species. Results of acoustic analysis impel us to infer that the female crickets take the comprehensive acoustic behavior to distinguish their specific male. In addition, behavior pattern and model of Gryllus bimaculatus are established as the comparison of interfering experiment is undertaken. Which results suggest that the mating behavior in cricket is dominated by males’ acoustic behavior, and is initiated by male’s olfactory sense rather than that of sight.
台灣水生食蟲植物~ 絲葉狸藻捕蟲行為及消化功能的進階探索
The “Insectivorous Plants”﹐ the first historical publication by Charles Darwin﹐contained the detailed observations and meticulous descriptions of various carnivorous plants and had become the most important reference for the study of carnivorous plants﹒ But the prey mechanism and digestive function of the bladder traps of the Utricularia were not well described﹒ The present study has a great success in these fields which include the volume change of bladder traps before and after firing﹐the spontaneous pressure relief of the bladder traps even without being triggered by prey, and the quadriceps visible absorption process﹒ The last two findings are not yet publicated. This laboratory experiment is carried out with Utricularia Gibba﹐a native species of Utricularia in Taiwan﹒ Through static and dynamic observation﹐we find that bladder traps suck in water by 12-25% of body volume change, and the bladder traps release internal pressure spontaneously under long period of waiting, despite not being triggered﹒ We can also easily demonstrate the absorption process of quadriceps by manually triggering the bladder traps to suck food color solutions. All the events above can be clearly seen under microscopy﹒達爾文是最先對食蟲植物作深入且完整研究的科學家，至今他的著作仍是研究食蟲植物的重要資料，但在其內容中對狸藻捕蟲囊捕蟲行為及消化功能的研究觀察並不完整。本實驗使用簡單的方法，在這方面有突破性的進展，包括捕蟲囊捕食前後的體積變化，自發性舒張及囊內腺毛對於食用色素的消化吸收，後兩項發現及實驗均未曾出現在文獻資料中。 本實驗以台灣本土水生食蟲植物絲葉狸藻(Utricularia gibba)為研究對象，由靜態及動態觀察，顯示捕蟲囊捕食前後體積變化為12~25%，且即使在沒有捕到水中生物的情況下，也會有自發性舒張以解除囊內壓力的現象。捕蟲囊內四爪腺毛消化吸收功能的整個過程，可藉由食用色素加以呈現，並清楚的在顯微鏡下觀察到這些現象。
利用滾動實驗測量摩擦係數
A cylinder rolling on an inclined plane and a sphere on grooved tracks are discussed in details.Using elementary mechanics, the formulas are derived for the time interval (t) and the final speed (vas a function of release height (h). (1) A cylinder is rolling down an inclined plane. The speed and time of the center of mass ofthe cylinder which changed with position (x) are recorded by a motion sensor. We can get theplots of v vs. √x and t vs. √ x, and find that the acceleration of the center of mass of thecylinder is constant, whether the cylinder is in rolling or a combination of rolling and slipping. (2) A sphere is rolling down an inclined grooved track. The final speed at the bottom of thetrack can be calculated from the physics of projection motion after the sphere leaves the track to thefloor. The time t for the sphere starting from rest to the bottom can be recorded by using photogate detectors. From the v-√h and t-1/√h graphs, μs between the sphere and track can be obtained. (3) When a sphere is released from the vertical height h of a cycloidal slide, the time tof pure rolling is the same independent of release position. But, when the sphere moves at a combination of rolling and slipping, the time t' will be different from t. We measure t and t' with photogate detectors and get the plot of t vs. h. The value ofμs can be calculated from the t - h graph. 圓柱或鋼珠從斜面或有槽曲面形成的軌道上滾下時，利用基本力學，可推導出時間 (t) 、速率 (v) 隨高度改變的函數關係。 (1) 利用運動感應器記錄圓柱由斜面上滾下時，圓柱質量中心的速度及運動時間隨位置 (x) 的變化，可繪出 v 對√ x 及 t 對 √x關係圖，由v－√x 及 t－√ x圖可知不論圓柱純滾動或滾動兼滑動，其質心均等加速度運動。 (2) 鋼珠由有槽斜板滾下時，到達底端的速率可由從底端至地面的拋體運動算出，而其時間t則可利用光電計時器直接記錄，利用 v－√h 圖及 t－1/√ h 圖可求出鋼珠和軌道的靜摩擦係數 μs。 (3) 鋼珠從旋輪線上方純滾動至底端時，所經歷的時間 (t) 和釋放高度無關，但是當鋼珠滾動兼滑動時，所經歷時間 t' 會改變，利用光電計時器量出 t 及 t'並作圖，利用 t－h 圖可出 μs。
Biological control of Aphis craccivora Koch., a common pest of the cow pea Vigna unguiculata(L.)
The purpose of this project is to control the Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) by using two predators, the earwigs (black) beetle, Proeus simulans Stallan and the ladybird beetle, Micraspis discolor (F.). The experiments were carried out in the closed system in the laboratory and in the opened field with various ages of Proeus simulans Stallan and Micraspis discolor (F.) from the 1st - 4th stage of embryo to the adult form. Prior to the study in the field, the capability of the predators, Proeus simulans Stallan and Micraspis discolor (F.), that can eat the Aphis craccivora Koch. within a period of time was set up in the laboratory. The result showed that the 1st-4th stage of embryo of Micraspis discolor (F.) can eat 8.46+1.25 – 12.50+0.60, at 95% confidence, Aphis craccivora Koch. per day, while its adult can eat at the average number of 43.66 + 0.78, at 95% confidence, per day. The 1st–3rd stage of Proeus simulans Stallan embryo and the adult form can eat Aphis craccivora Koch. at the average number of 2.37+0.33 – 3.74+0.29 and 9.84+0.36, at 95% confidence, per day, respectively. This data showed that Micraspis discolor (F.) was more efficiency as predator than Proeus simulans Stallan. The insecticide activity of these two predators in the closed field (8 m x 9 m) was then determined. The number of Aphis craccivora Koch. on the plant was randomly counted everyweek for 10 weeks. It was found that the number of Aphis on the experimented and control groups were 16.20+4.30 and 2,582.00+102.40, at 95% confidence, per plant, respectively. The result support the efficiency of the two predators in controlling the pest. When the experiment was set up at the two opened field (6 m x 30 m, each field), 27.51+2.74 and 52.11+5.21, at 95% confidence, of Aphis craccivora Koch. were found on the plant of experimented and control groups, respectively, at the 10th week. The lower number of Aphis on the control plant might possilbly due to the interference from natural predators. From this study, the biological control of Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) could be achieved by using Proeus simulans Stallan and Micraspis discolor (F.). To avoid the use of chemical insecticides, biological control should be trained to farmers to help reduce the environmental problem.
STATIN 類降血脂藥物對血管平滑肌細胞一氧化氮合成?的基因調控作用
動脈硬化是個致病率和致死率相當高的慢性發炎疾病。HMG-CoA 還原酵素抑制劑 纇藥物，簡稱statin, 是一類強效的降血脂藥物，而且在臨床上對於心血管疾病有廣泛的 治療效果。然而近年來的研究報導指出，statin 會有如此廣效治療效果，其原因不僅僅 是因為它的降血脂能力，而是statin 也具有抑制發炎作用的效果。雖然臨床上已經證實 statin 可以減緩動脈硬化的病程，但是statin 對於誘發型一氧化氮合成酵素(iNOS)表現的 調控機制還不明確。有文獻指出NOS 代謝產物nitric oxide (NO)可以改善血流，而可能 在動脈硬化上扮演保護角色。值得一提的是雖然適量 NO 有維持血管恆定的功能，過 量時則會造成血壓過低休克的現象，這就是細菌感染後因內毒素 lipopolysaccharide (LPS) 作用引發敗血性休克的主要原因之一。在本實驗中，我們使用fluvastatin、lovastatin、 pravastatin 和 atorvastatin 這四種statins 來探討它們對於血管平滑肌細胞由LPS 及IL-1β 誘導iNOS 基因表現的影響。我們發現，statin 可以抑制LPS 所誘發的NO 和iNOS 表現， 但卻會促進IL-1β所誘發的反應。NF-κB 在iNOS 的基因調控上扮演重要的角色，而在 探討NF-κB 被LPS 和IL-1β活化的情形中，statin 同樣會促進IL-1β活化NF-κB，但抑制 LPS 活化NF-κB。我們也發現fluvastatin 對於IL-1β所引發NO 的產生、iNOS 的表現、 NF-κB 的活化，以及p65 向細胞核移動的促進作用，在ROCK 抑制劑Y-27632 的處理後 可以看到相同的現象。IKK kinase assay 顯示Y-27632 對於LPS 所促進的IKK 活性影響 很小，但是會促進IL-1β的活化作用。接著，在ROCK 的活性方面，LPS 會抑制原本已 表現的ROCK 活性， 而相反的，IL-1β會增加ROCK 的活性。總括來說，這些結果顯示 ROCK 在血管平滑肌細胞中扮演IKK/NF-κB 的負向訊息調控者角色，而這個機制在LPS 和IL-1β的訊息傳遞路徑中有不同的調控。即ROCK 以負向調控機制角色影響IL-1β的 訊息傳遞，卻不存在於LPS 的情況中。就是因為透過反轉這個負向調控的機制，statins 3 和ROCK 抑制劑對於LPS 及IL-1β引發血管平滑肌細胞的iNOS 表現，呈現相反的調控 結果。這些作用可能參與statin 預防血管再阻塞，抗發炎，抗動脈硬化的作用。此外Statin 抑制LPS 的iNOS 表現作用或許將來可運用於治療敗血性休克。利用基因微陣列分析也 偵測到一些受fluvastatin 正向或負向調控的基因，目前我們正朝鑑定基因的表現改變及 確認其功能，生理意義進行實驗中。 The 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitors, statins, are potent inhibitors of cholesterol synthesis and have wide therapeutic use in cardiovascular diseases. Recent evidence, however, suggests that the beneficial effects of statins may extend beyond their action on serum cholesterol levels. Although statins have been shown to reduce progression of atherosclerosis, little is known about mechanism by which statins affect iNOS expression. Optimal level of NOS product, NO, possesses the anti-inflammation and anti-proliferation effects in atherosclerosis, while large amount of NO contributes to the septic shock in response to bacterial endotoxin, lipopolysaccharide (LPS). In this study, we investigated the effects of fluvastatin, lovastatin, pravastatin and atorvastatin on IL-1β- and LPS-induced NO production in cultured rat vascular smooth muscle cells (VSMC). We found statins can inhibit LPS-induced iNOS expression and NO production, while they can potentiate IL-1β-elicited responses. In studying the activity of NF-κB, which plays an important role for iNOS gene induction, we found that fluvastatin can increase IL-1β-induced p65 nuclear translocation and NF-κB activity, while inhibit those induced by LPS. The potentiation effects of fluvastatin on IL-1β-induced NO production, iNOS expression, NF-κB activation and p65 nuclear translocation were all mimicked by a ROCK inhibitor, Y-27632. IKK kinase assay showed that Y-27632 itself has minimal effect on LPS-induced IKK activation, while enhances the response of IL-1β. Studies on examining ROCK activity showed LPS can downregulate constitutive ROCK activity, while IL-1β oppositely increases ROCK activity. Taken together these data suggest ROCK is a crucial negative regulator of IKK/NF-κB signaling pathway in VSMC, and this negative control is existing in the action IL-1β, but is absent in the action of LPS. Through abrogating the function of this negative regulator, statins and ROCK inhibitor thus differentially regulate iNOS expression induced by LPS and IL-1β in VSMC. These results suggest that stimulation of iNOS expression in the presence of IL-1β might contribute to the beneficial effects of statins in atherosclerotic process in terms of vasodilation, anti-inflammation and inhibition of smooth muscle cell proliferation. In contrast, the diminishing effect on LPS-induced NO response possibly may provide new therapeutic strategy in sepsis. Al these results strengthen the pleiotropic actions of statins in anti-inflammation and anti-atherosclerosis. Preliminary microarray analysis further revealed several genes either upregulated or downregulated by fluvastatin. The identification of these genes and studying their functional roles in atherosclerosis are currently in progress.
超越極限的越野蟑螂車
在本研究中，我模仿蟑螂的行走方式，來製作可以在各種地形以不減速的方式前進的機器車。在偶然機會下，我觀察到，蟑螂可以順利爬越米堆，因此對蟑螂的運動方式感到興趣。我用微型網路攝影機拍攝及觀察蟑螂的行走方式。發現蟑螂在快速行走時，是以三隻腳為一組，六腳兩組交互進行前進的動作。由於三點構成一平面，使蟑螂在快速移動時，相當的平穩。我將此原理融入蟑螂車的設計，並根據這個原理，利用舊玩具四驅車改裝成「六驅車」，成功的製作出模仿六足昆蟲行走方式且可以在各種地形順利前進的機器車。為了更客觀的比較，我應用樂高積木的馬達組合，製作了一部純轉動前進的六輪傳動車，及另一部轉動兼走動的六輪蟑螂車。並利用微電腦控制兩種車維持相同的驅動速度前進(93.33 rpm)，於各種路面實地測試，證實蟑螂車越野的性能的確強很多。未來若可以將六足昆蟲行走方式的概念應用到汽車製造，車輛的越野性能必然大幅提昇。\r \r In this research, I developed a six-wheel driving vehicle simulating the movement of cockroach. The resultant motion machine can un-intermittedly run on terrains without speeding down. Occasionally, I observed that the cockroaches can crossover a heap of rice. Therefore, I was very interested in and eager to learn how cockroach runs. I recorded the movements of cockroaches by using mini web camera and analyzed the moving characteristics of cockroaches. It was discovered that the cockroach marches quickly by interchanging two groups of foot in which each group consists of three feet. As a table can be supported by three legs, the cockroach runs steadily and rapidly. I have designed a motocross vehicle based on the mechanism of the way that cockroach runs. A six-wheel driving car is constructed by modifying four-wheel driving toy cars. By simulating the motion complex of six-foot insects, the six-wheel driving car turns out to be an all-terrain vehicle. To be more objective in comparison, I built two types of six-wheel driving cars by utilizing the LEGO TECHNIC motor building set: one with regular and synchronous rotation, and the other one with eccentric shaft rotation emulating cockroach marching movement. I applied a microprocessor to control the motors in order to maintain the same driving speed (93.33 rpm) for both cars during the road test. The experimental results show that the proposed cockroach motocross car performs superiorly especially for the rugged terrain. In the future, the off-road capability of a jeep can be improved by introducing the concept of six-foot insect movement to vehicle design.