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Evaluation of Cadmium Content Level in Vegetables by Soil Characteristics
No full text本研究依據前人研究提出之蔬菜鎘含量預測模式，整合雲林縣農地土壤特性參數等相關資料，推估雲林縣農地種植不同蔬菜的鎘含量，並配合國人蔬菜消耗量檢視國人食用這些蔬菜的安全性；亦對蔬菜鎘含量預測模式的係數進行敏感度分析，探討影響預測模式中蔬菜鎘含量的主要因子。研究結果發現，平均鎘濃度推估最高的5種蔬菜為福壽/翠花萵苣、菠菜、尖葉萵苣、圓葉萵苣及莧菜。由於蔬菜的重金屬鎘限量標準規範依不同種類而異，歸納出比較容易超標的蔬菜種類是半結球類、瓜菜及果菜類及大蒜。因為國人對葉菜類需求較其他類別蔬菜高，葉菜類之中的小葉菜類蔬菜鎘濃度整體來說比較高，所以葉菜類攝食成為鎘進入人體的主要途徑。最後經由敏感度分析得知，蔬菜鎘含量預測模式中γ絕對值大的蔬菜，在土壤CEC低時會致使蔬菜鎘含量顯著增加；δ絕對值大的蔬菜，種在土壤pH值低的地方，其鎘含量會比種在高土壤鎘濃度情況下為高。根據以上結果，建議有關單位可以參考本研究結果選擇蔬菜適栽地點，並且留意小葉菜類蔬菜的鎘含量，以減少產出含鎘超標蔬菜。Based on the predictive model for Cd content levels in vegetables proposed by Taiwan Agricultural Research Institute in a former research, this study integrated soil characteristics parameters needed for the model to predict Cd content of 31 vegetables cultured in Yunlin County. The vegetable consumption is one of the major pathways of Cd uptake in Taiwan residents. If we can understand the Cd content in vegetables, then we can manage health risk better. The aim of this study is to estimate Cd content level in various vegetables to be planted in Yunlin County, which is the most important production area in Taiwan. This study further conducted sensitivity analysis of coefficients in the predictive model for Cd content levels in vegetable to find out the main factors affecting Cd content in vegetables. The model predicted that there could be 5 vegetables with the highest Cd content level, including iceberg lettuce, spinach, two kinds of leaf lettuce and amaranth. This study also found some classes of vegetables that could be easier to exceed their regulatary standards for Cd content, including head vegetables, melon vegetables and fruit vegetables and garlic. In addition, this study predicted that leafy vegetables could have higher Cd content and may become a main pathway of Cd uptake because Taiwan residents currently eat more leafy vegetables than other vegetables. Finally, the model sensitivity analysis showed that vegetables with higher γ would gain more Cd content when planted in the soil with lower CEC; vegetables with higher δ would gain more Cd content when planted in the soil with lower pH than in the soil with high level of Cd content. This study suggested agricultural authorities can use the results of this study to guide farmers to choose planting suitable vegetables in right locations, to pay attention to cadmium content in leafly vegetables, and to reduce the production of vegetables with high Cd content
Distribution of wintering Numenius arquata in Chang-hua coastline, Taiwan
No full text度冬水鳥利用潮間帶灘地覓食補充能量，水鳥在灘地上的分布和灘地類型有關。在過去三十年，台灣度冬大杓鷸（Numenius arquata）在彰化灘地歷經分布改變和數量減少。分布改變代表適合棲息的環境改變，欲了解分布改變之因，需先了解大杓鷸分布於何種灘地類型。觀察大杓鷸在彰化海岸的分布，以及分布範圍內的底質類型，發現大杓鷸分布主要分布在芳苑外海灘地，分布範圍內地底質為泥質，在灘地上的主要行為為休息和覓食。為探討彰化海岸底質分布，利用大地衛星影像進行監督式分類和138個現場灘地的底質資訊，將彰化灘地底質分為沙質和泥質，結果顯示衛星影像分類之整體精確度為94%。由影像分類結果發現彰化海岸許多地方是泥質底質，但大杓鷸分布僅在芳苑外海灘地，顯示有其他因子影響大杓鷸在泥質灘地的分布。檢測漲潮停棲點和人為干擾是否對大杓鷸在泥質灘地分布有影響，比較有大杓鷸分布之泥質底質與無大杓鷸分布者，距漲潮停棲點、風力發電機、蚵架、台61西濱高架快速道路之最近距離有無差異。結果顯示有大杓鷸分布的泥質區域距漲潮停棲點較近，且距風力發電機、台61西濱高架快速道路較遠。本研究顯示彰化度冬大杓鷸族群偏好泥質灘地，且其分布之泥質區域距離漲潮停棲點近、距高架道路較遠。過去三十年，風力發電機、台61西濱高架道路尚未建立，欲探討分布改變，可以泥質灘地變遷、漲潮停棲點位置的變化來探討。欲保育彰化海岸大杓鷸的棲地，除了保育灘地底質之外，需將漲潮停棲點的位置和高架道路的干擾納入考慮。Mudflat is the primary foraging habitat of wintering shorebirds. Shorebird distribution is related to mudflat type. The wintering population of Eurasian Curlew（Numenius arquata）shifted its distribution in the past 30 years in Chang-hua coastline. Curlew distribution change represents changes in their optimal habitat. In order to understand the cause of the distribution change, we must understand the preferred mudflat types for curlews. To do so, we observed wintering curlews’ distribution range on intertidal mudflat in Chang-hua coastline and studied the mudflat types in their distribution range. We found curlews mainly distribute themselves in Fang-yuan mudflat; furthermore, they seemed to prefer muddy substrates. Whilst there, their major behaviors included resting and feeding. To understand the substrate distribution of Chang-hua region, we collected 138 samples in the field and used Landsat satellite imagery to classify the mudflat type to ‘sand’ and’ mud’ through supervised classification. The overall accuracy of the classified map is 94%. Form the classified theme map, it was apparent that there were many muddy areas in Chang-hua coastline, but curlews, however, distributed themselves in particular muddy region of Fang-yuan. This suggested that there are others factors that affect curlews’ distribution on ’ muddy’ mudflats. We test whether if the distance to high tide roosting sites and human disturbances affect curlews’ distribution on ’muddy’ mudflat. Comparing between the ‘muddy’ mudflat areas with curlews and those without, we tested whether if the distances to (1) high tide roosting site and (2) wind turbines, (3) oyster culturing structure and (4) No. 61 West Coast Expressway were the factors in terms of curlew distribution. Our result revealed that curlews were distributed in ‘muddy’ regions near high tide roosting site. They were, on the other hand, distributed further away from wind turbines and No. 61 West Coast Expressway. 30 years earlier, none of the aforementioned infrastructures constructed. In hope to better understand curlews’ distribution change over the past 30 years, future studies must investigate (1) the change of ‘muddy’ mudflats and (2) the change in high tide roosting sites in north Chang-hua. Present study highlights the importance of mudflats on curlew conservation. While placing emphasis on the distance to feeding and roosting sites, it has come to light that various types of human disturbances may also play an important role in the distribution preference of the Eurasian Curlew
Automatic Multi-Feature Extraction for Clinical Colonoscopy Image Analysis and Recognition
No full text針對大腸鏡篩檢的影像，本論文提出了擷取盲腸與非盲腸之結構特徵的分析系統，利用特徵在兩者臨床照片中表現之不同，找出多維度的特徵向量，作為我們建立之分類系統的訓練資料，用以提升分類器之準確性和強健性，以及利用影像處理之結果，協助醫師判斷之目的。 近年來，人類的飲食習慣與生活與過去越來越不同，社會大眾對於自身的腸胃道系統也日益重視，消化系統相關的疾病儼然成為重要的課題，其中，又以大腸癌為國人罹患人數前三名以及高花費的病症。為了預防大腸癌以及維持良好的腸胃環境，國內外定期大腸鏡篩檢的需求量也不斷成長。然而為了達到有效的篩檢目的，完整的檢查程序是必須的，其中盲腸到達率(CIR)是檢查品質判斷一項非常重要的指標，故本論文注重於探討CIR以提升大腸鏡檢查的整體效益。我們提出一個系統架構，能夠基於影像處理的演算法，自動地辨識出影像中盲腸(Cecum)的結構表現，如回盲瓣Ileocecal Valve (ICV) 、微笑紋路Tri-radiate Fold、闌尾孔Appendiceal Orifice，另外，非盲腸部分的結構表現也是系統的擷取目標，並基於兩者的表現差異，找出多面向並且具有區別力的特徵，做為分類的依據。 本論文提出一套大腸鏡影像分析方法，包括有效地抑制如反光、血管、積水和糞便等雜訊，並找出適當的特徵值區別盲腸與非盲腸的結構表現，產生多維度特徵向量，提供整個大腸鏡影像分類系統的辨識。在此篇論文中，我們改良了先前研究單純針對單一亮度作為特徵擷取的演算法，提出Particle Filter將亮度特徵做一最佳化的擷取，另外，我們從Edge-Based、Histogram-Based 以及Texture-Based等不同方面進行大腸鏡影像的分析，包括Feature Extraction和Image Segmentation。最後我們另一位計畫夥伴將進一步以AdaBoost Machine Learning的方式進行特徵訓練，並得到一個將醫師上傳之大腸鏡影像分為盲腸或非盲腸之分類器。本論文提出的演算法，以臺大醫院提供之臨床影像，總共包含664位病人資料，我們隨機挑選出1009張盲腸與997張非盲腸影像作為訓練與測試，將結果與整體系統整合之後，最後我們得到了平均94.0%與最佳96.9%分類的準確率，並且基於這些特徵自動地標記出大腸鏡影像中之重要結構提供醫生作為判斷時之第三方參考。We proposed an analysis system to extract the features of cecum and non-cecum structures of clinical colonoscopy images. We found out the different expression of these two cases and obtained multiple features after extraction as the training data for our classifier of system. The proposed algorithm helped improve the accuracy and robustness compared to the previous work. Besides, we also provided assistance to doctors for their judgments with the result of image processing on colonoscopy images. In recent years, the dietary habit and life of people had become very different nowadays, and the concerns of the digestive system related diseases had become more and more serious issue to people. Among these, colorectal cancer has the high incident rate and high cost within the top ranks in our country. To prevent colorectal cancer and maintain good digestive environment, the demand of regular colonoscopy is increasing around the world. However, to achieve the purpose of the examination effectively, complete procedure is essential. The cecal intubation rate (CIR) is the critical quality indicator of colonoscopy completion, which is our system mainly focus on. We proposed an image processing based system, which could automatically recognize the landmarks of cecum images such as Ileocecal valve (ICV), Tri-radiate Fold and Appendiceal Orifice. In addition, we also found the structures of non-cecum images. And we determined the features to demonstrate the difference between these two cases performance for our classification accordance. We developed an approach to analyze colonoscopy images, including reducing the noises such as reflection, veins and dirt of excrements. Further, we extracted vector of multiple features to describe cecum and non-cecum structures’ performance properly for the classification and recognition in our system. In this thesis, we applied Particle Filter algorithm to have better result compared to previous work, which used merely single lightness threshold as the classification feature. Moreover, Edge-Based, Histogram-Based and Texture-Based are the additional aspects we utilized to extract our features for colonoscopy images analysis, including classification and segmentation. Finally, we pass our feature vector as training data to another partner in our project, who is focus on developing Machine Learning using Adaboost algorithm for the classification dealing with the photos uploaded by doctors. The material of our experiment was provided by NTU hospital, which were totally 664 patients’ folder of clinical colonoscopy images. We randomly selected from it and got 1009 cecum images and 997 non-cecum images for our training and testing purpose. At last, we not only got average 94.0% and best 96.9% accuracy of classification performance, but also marked the vital landmark of cecum and non-cecum structures for doctors’ analysis
An ecophysiological study of Drosera indica, a rare carnivorous plant in Taiwan
No full text長葉茅膏菜 (Drosera indica) 為一年生草本植物，全株具有會分泌黏液之腺體，可捕捉獵物。目前台灣本島僅剩竹北蓮花寺濕地有較穩定族群，但須透過人為管理才得以維持。本研究：(1) 透過觀察野外、農場種植族群及石蠟切片等方式，了解長葉茅膏菜生活史及內、外部構造。(2) 使用穩定性同位素技術探討生長於濕地之長葉茅膏菜是否有透過捕捉獵物補充氮源，並用模式計算蟲源氮之比例；在台大農場進行隔蟲處理實驗，以探討獵物對長葉茅膏菜生理及生長之影響。(3) 假設濕地伴生植物過度生長限制長葉茅膏菜之族群數量，因此在該濕地進行除草及除草加翻土處理以驗證；並在台大農場及生長箱內進行光度及溫度操控實驗，以了解伴生植物影響長葉茅膏菜族群數量之可能機制。 觀察發現，濕地長葉茅膏菜大約於3月萌芽，5月開始開花，持續至10月左右結束生長季。植株高度變化很大 (15 ~ 50 cm)，與過去文獻紀錄有差異 (約20 cm)。花柱開裂呈Y字形，交錯於雄蕊之間，且花朵有日週期性開閉運動，可能會使柱頭沾附自花花粉。葉片上具有長、短柄腺體，長柄腺體是數百個細胞組成的複合體，分成頭狀構造及柄狀構造；短柄腺體是由8個細胞所組成。分析結果顯示野外長葉茅膏菜之穩定性氮同位素比值顯著高於伴生植物，代表其有不同的氮來源，估算植株約 46 ~ 58 % 的氮是從獵物獲得。而從隔蟲實驗結果得知：捕捉獵物可增加植株的氮含量及種子產量。蓮花寺濕地經除草及除草加翻土處理之樣方，土壤所接受到的光度及土壤溫度變化趨勢與控制組樣方不同，且兩種處理都有助於增加長葉茅膏菜族群數量。種子萌芽及生長環境光度操控實驗結果顯示：長葉茅膏菜種子需照光才會萌芽，且在低溫會有休眠現象；生長於高光環境植株會有較高的生物量及種子產量；生長於中光環境植株徒長且生物量及種子產量較低；多數低光環境生長植株未開花、結果即死亡。 綜合野外操控及光度、溫度生長實驗證實，在蓮花寺濕地由於伴生植物過度生長，使得長葉茅膏菜種子及植株無法接收到足夠的光度以萌芽及生長，導致族群數量下降，透過除草增加土表接受到的光照度可以有效提高族群數量，因此光度為限制野外長葉茅膏菜族群數量之重要環境因子，而土壤溫度是造成長葉茅膏菜有明顯生長季原因之一。Drosera indica is an annual herb with many glandular trichromes, which could secrete mucus to help capturing small arthropods. Currently in Taiwan island, its populations are only found in the wetland of Lienhwa Temple and maintained by artificial disturbance. There are 3 aspects of this study. (1) To understand life cycle, morphology and anatomy of leaf and root of D. indica, I observed wild populations and made histological section. (2) To investigate whether D. indica uptakes nitrogen from captured prey and to estimate the nitrogen (N) sources, derived from root (Nr) and prey (Np), I analysed stable nitrogen isotopes ratio (δ15N) of D. indica, accompanying plants and potential prey. I also grew D. indica in two environments, control and prey excluded, to examine if Np has beneficial effect on D. indica’s growth and reproduction. (3) I hypothesized that the overgrowth of accompanying plants in the wetland inhibited the population of D. indica. To test the hypothesis, I conducted weeding and weeding then rooting treatments at the habitat then examined the effect of these treatments on the population of D. indica and microclimates. I also studied the effects of light and temperature on seed germination and growth of D. indica to evaluate the underlying mechanisms responsible for the inhibition effect of accompanying plants on the D. indica population. In the wetland, D. indica started germinating in March, flowering in May and continued blooming till October. The height of D. indica was about 15 ~ 50 cm, which was different from previous reports. Its flowers have 3 ~ 4 bifid styles, of similar height and entangling with stamens. Self-pollens might adhere on stigmata due to daily flower movement. There are many long and short stalked secretory glands on leaves. Long stalked secretory glands consist of stalked structure and head glandular. Short stalked secretory glands consist of eight cells. The δ15N of D. indica was significantly higher than that of accompanying plants indicating acquiring N source from prey, which was estimated about 46 ~ 58 % of all N content. The capturing of prey increased leaf [N] and the production of seeds of D. indica. Results from field experiments revealed that pattern of variety of photosynthetic photon flux density (PPFD) and soil temperature differed between control and treated plots, and treated plots grew significantly more D. indica plants. Growth chamber experiments showed that seeds of D. indica could not germinate in dark, and remained dormant at low temperature. D. indica grown in high light environment had highest biomass and produced more seeds; those in medium light elongated and produced less seeds; most of those in low light died before flowering. Consequently, these results suggest that D. indica in wetland might not receive enough light for germination and growth due to overgrowth of accompanying plants. In conclusion, light is an important factor limiting the population growth while soil temperature plays an important role in starting the life cycle of D. indica in wetland
Correlation analysis between ECG and EEG signals based on signal complexity
No full text緒論 生命的祕密至今無解。各種律動組合成人體的運作，是維持生命的要素。這些律動彼此交互影響、形成迴路、並共同與擾動的、多變的環境發生應對。他們提供組成生命所需有序的功能。回顧歷史，心臟在許多不同文化裡被視為是情緒和智慧的本源。大多數的神經科學家認為意識及思考只是大腦及其相關的神經生理功能。然而，心臟在腦形成以前已經開始跳動。傳統說法，心與腦經由神經及荷爾蒙兩種路徑互相溝通，其溝通是否也能經由個別律動內所隱藏的動態變化，則令人好奇。心律變異是心臟自主神經系統的指標，腦波動態變化則被證明與意識活動有關。本論文始於複習非線性訊號分析。生物訊號屬於多尺度、非線性且非穩定性序列，混沌理論是否可行不需執著，非隨機的複雜性的確存在於生物信號中。我選擇以探討規則的統計為中心的複雜性分析來探討心腦連結問題。同步記錄及非同步記錄的腦波及心電圖都將被使用。實驗對象使用一群老人，基本上心臟功能健康、而意識功能則從健全到失智拉開分布。腦的電磁活動運轉非常迅速，類穩定的腦波信號是非常短的，處於幾十秒的尺度。因此我採用符號動力學方法來分析同步信號。腦波的來源至今未有定論，其中新近被討論的皮層慢電位，其頻率範圍接近心臟的。我採用非線性、直覺性的方法來著手探討皮層慢電位。並且對於腦波之電位及即時頻率兩個成分將分開探討。 研究方法及材料 實驗對象包含89個老年門診病患，分為三個族群，38個血管型失智症、22個阿茲海默症、以及29個智能健全的對照組。多尺度熵分析(Multiscale entropy)用以分析非同步的腦波心電圖，符號動力學方法用以分析同步的腦波心電圖。另外分散信號的方法用以將波幅及即時頻率分開。傅立葉頻譜低頻對高頻比(LF/HF)用以代表交感副交感神經平衡指數。 結果與討論 在非同步信號經由多尺度熵分析，我發現心腦信號之複雜動態間，的確存在線性關係。但短暫的同步信號之間並無關聯證據。這可能因為同步於腦波的心律變異太短，無法穩定表現個案特質。不過，符號動力學方法顯示: 每個分散的腦波局部高峰，其電位值的變異與智能相關，但是腦波的及時頻率並不相關。這表是局部同步激發的皮質神經元數量而非其激發的時機與智能相關。熵的值，或說複雜度，亦即規則性的強弱並不代表健康度。不同方法測量的是生物信號的不同尺度。在腦波分析方面，分散信號的方法所得到的資訊，並不亞於全波形的分析。失智的病理表現可能是連續性而非階梯式的。Introduction The secret of life remains extremely concealed. There are all sorts of rhythms in human bodies and they are central to life. The rhythms interact with each other as well as the outside fluctuating, noisy environment under the control of innumerable feedback systems. They provide an orderly function that enables life. The heart has been considered the source of emotional experience and wisdom in many cultures throughout the ages. Most neuroscientists consider consciousness or even thought is merely an epiphenomenon of the human brain function and its associated neurophysiology. However, the heart begins to beat before the brain is formed. Conventionally, both neural and humoral pathways connect the heart with the brain. Whether the interplay between the heart and brain could be explored through their rhythms is the question. Heart rate variability is recognized as the indicator of cardiac autonomic function. The dynamics of human electroencephalography (EEG) dynamics has been proved to be related to cognitive activities. This dissertation starts with reviewing the nonlinear methods in analyzing biological rhythms, which are multiscale, nonlinear and non-stationary. Regardless of whether chaos is present, deterministic complexity exists in biological rhythms. Regularity based complexity was chosen after comparisons. The goal is to find correlations between EEG and electrocardiography (ECG) through regularity based complexity analysis. Both simultaneous and non-simultaneous data would be examined. The experimental subjects are from a geriatric sample with varied cognitive abilities and basically healthy hearts. The electromagnetic activity of the brain works at an extremely fast speed, and the quasi-stationary epochs of EEG are, in general, short lasting, in the order of tens of seconds. Therefore symbolic techniques were introduced when exploring the very short simultaneous EEG and R-R interval (RRI) data. The origin of EEG remains unknown. Slow cortical potential (SCP), one component of EEG, is in the frequency range similar to that of the heart, and would be explored in an intuitive nonlinear way. In addition, the amplitude and instantaneous frequency of EEG would be separately approached. Methods The sample consisted of 89 geriatric outpatients in three patient groups: 38 fresh cases of vascular dementia (VD), 22 fresh cases of Alzheimer’s disease (AD) and 29 controls. Multiscale entropy (MSE) analysis was applied to the non-simultaneous EEG and RRI data. Symbolic analysis was applied to the simultaneous EEG and RRI data. Discrete events (local peaks) of EEG were extracted to separate the amplitude and instantaneous frequency. The low-to-high frequency power (LF/HF) ratio of RRI was calculated to represent sympatho-vagal balance. Results and Discussions MSE revealed correlations between the signal complexity of brain and cardiac activities in non-simultaneous data. Linear correlation between the MSE value and the score of the mini-mental state examination was first found. Symbolic dynamics failed to correlate the heart to the brain. This is due to that the RRI is too short to represent the characteristics of a subject. The symbolic analysis revealed important information that the EEG dynamics which relates to either the cognitive functions or the underlying pathologies of dementia are embedded within the dynamics of the amount of but not the interval between each synchronized firing of adjacent cerebral neurons. Just like RRI of ECG, discrete events of EEG also provided important information. The relative value of complexity does not indicate health condition straightly. It depends on the method and the scale or dimension that particular method measures. Discrete events provide no less information than continuous waveforms of EEG. Pathological condition is continuous rather than stepwise
Roost Characteristics and Temperature Buffering of Female Red-Giant Flying Squirrel (Petaurista philippensis) in Fushan Experimental Forest
No full text本研究藉由測量福山試驗林大赤鼯鼠（Petaurista philippensis grandis）的棲所形值、溫度以及雌性個體於不同繁殖階段的棲所使用情形，來檢驗雌性大赤鼯鼠對棲所形質的使用偏好是否受到棲所緩衝環境溫度變化的程度所影響，也就是棲所形質是否影響棲所緩衝環境溫度變化的程度繼而影響大赤鼯鼠對棲所的利用。本研究於 2011 年 7 月至 2013 年 4 月間，共發現大赤鼯鼠棲所 89 個；無線電追蹤 5 隻雌性成體的結果顯示其活動範圍平均 0.96 ± 0.13 公頃，活動範圍與棲所使用在雌性個體之間有明顯的區隔。雌性大赤鼯鼠偏好具有冬季樹冠覆蓋比例低、大容積、小開口與高度較低等特徵的棲所，且顯著偏好使用對緩衝環境溫度變化效果較佳的棲所，並對此類棲所有較高的棲所忠誠度。而雌性個體偏好的大容積形質對夏季全日最低溫（Tmin）、夏季日均溫（Tave）與冬季日溫差（Tran）的緩衝效果顯著較佳，符合雌性大赤鼯鼠對棲所形質的偏好是因為此棲所形質能夠緩衝環境溫度變化的假說。此外，雌性個體也對其他與溫度緩衝沒有顯著相關的棲所形質表現偏好或較高棲所忠誠度，則可能與其他非溫度相關的因子有關。To examine whether roost characteristics affect temperature in roosts and roost preference or fidelity of female Petaurista philippensis grandis, we measured the characteristics and temperature inside and outside of roosts of P. philippensis, and monitored roosts utilization and home range of adult females at difference reproductive stages by observation and radio tracking at Fushan Experimental Forest. We radio-tracked 5 female adults and found 89 roosts used by them from July 2011 to April 2013. Results of this study indicated that the average home range of these females is 0.96 ± 0.13 ha. Home range of these females hardly overlapped and none of their roosts was shared by more than one adult female. Female P. philippensis showed preference to roosts with low canopy cover in winter, large volume and small entrance as maternity roosts. They also showed preference and higher fidelity to roosts with better temperature buffering capacity. In addition, roost with large volume showed higher minimum temperature, average temperature in summer and daily temperature range in winter. It suggests that female P. philippensis prefer specific roost characteristics which are related to better temperature buffering capacity. The temperature buffering capacity of roost partly explained the roost characteristics preferred by female P. philippensis. However, there may be other non-temperature related factors affecting roost preference and fidelity of female P. philippensis
Effect of habitat alteration and Allee effect on the elevational distribution in burying beetles (Nicrophorus nepalensis)
No full text人類活動造成的棲地改變除了影響環境的非生物因子，也可能改變生物之間的互動，進而影響物種分佈或存續。在探討限制物種分佈的因子時，較多研究支持非生物因子，支持生物因子則較少，主要機制為種間競爭，種內的互動則鮮少被提及。種內互動可能的機制是艾里效應，其描述當族群密度下降時，族群內個體的適存度跟著下降的現象，理論上會因棲地改變影響族群密度而發生。然而鮮有研究討論棲地改變與物種分佈範圍的關係時，同時考慮上述三種因子。尼泊爾埋葬蟲（Nicrophorus nepalensis）在台灣的中部橫貫公路廣泛地分佈，而在中橫西部有大規模的開墾，東部則無，剛好適合我們測試棲地改變如何透過生物與非生物因子造成此分佈改變。我們提出了（1）微氣候條件假說：棲地改變影響微氣候因子而限制了物種的生理；（2）種間競爭假說：棲地改變提高競爭者競爭能力或增加競爭者數量而增加了種間競爭壓力；（3）艾里效應假說：棲地改變致使族群密度下降，影響物種在環境壓力下的表現，進而改變物種分佈。我們在兩地沿著海拔進行尼泊爾埋葬蟲密度調查與繁殖實驗，以繁殖成功定義分佈範圍。發現相同微氣候條件下，東部繁殖範圍較廣，同時東部種間競爭壓力較大，故拒絕了前兩項假說。我們發現東部族群密度較高，族群密度與繁殖群大小呈正相關，而在海拔較低處群大小又與成功率呈正相關。在兩區域沿海拔操作繁殖個體數以模擬高與低密度條件則發現，在海拔較低處，皆是放入6隻個體共同繁殖時較僅2隻時繁殖成功率高，且兩樣區沿著海拔操作密度的趨勢相同，證明造成兩區域埋葬蟲分佈與繁殖差異的關鍵因子在於族群密度，證實艾里效應假說。我們的研究顯示，棲地改變對埋葬蟲的分佈造成影響，並非直接由非生物因子或種間競爭造成，而是透過降低族群密度，使埋葬蟲溫度高競爭壓力較強的海拔無法對抗其競爭對手，限縮了埋葬蟲可繁殖的海拔下界。我們的結果闡明了種內生物因子也是棲地改變影響族群分佈不可或缺的機制，因此保育研究應當更全面地探討生物之間以及生物與環境的關係，方能有效避免生物多樣性持續快速消失。Habitat alteration impacts the distribution of species and population dynamics through changing biotic or abiotic factors. Most studies have focused on the changes in abiotic factors, such as temperature, when considering the effect of habitat alteration on species distribution. The role of biotic factors, such as interspecific competition, remains largely unexplored. Furthermore, there are even fewer studies investigating the synergistic effects among abiotic, inter- and intraspecific factors on the distribution of species. Here, we used the burying beetle, Nicrophorus nepalensis, a widely distributed cooperatively breeding species, to study the ecological impact of habitat alteration on the distribution of species. Our study was conducted along two elevational gradients in the central cross-island highway of Taiwan, where the habitats on the west side are extensively altered but nature forests on the east side remain intact. Specifically, we test three alternative, but non-mutually exclusive, hypotheses: (1) “microclimate condition hypothesis”, which means that microclimate alteration in the habitat limits the reproduction of N. nepalensis; (2) “inter-specific competition hypothesis”, which argues that habitat alteration enhances the competitive ability of interspecific competitor, flies; and (3) the “Allee effect hypothesis”, which states that habitat alteration decreases the population density of N. nepalensis, which, in turn, impacts its competitive ability against the flies. Our results showed that, by comparing the microclimate data and group size of flies in natural forests along the two elevational gradients, we rejected the first two hypotheses because the microclimate conditions of the two elevational gradients were similar and the numbers of the flies on the east side were even larger than it was on the west side. Interestingly, we found that the group size was positively correlated with the population density of N. nepalensis, and the probability of successful breeding was positively correlated with the group size of N. nepalensis at the lower elevation. Also, we experimentally manipulated the population density by placing high density (three males and three females) and low density ( one male and one female) in the breeding boxes in the field at two gradients. We found that the probabilities of successful breeding were the same between the two gradients, where the high-density treatment had a higher successful rate than the low-density treatment, small group, supporting the Allee effect hypothesis. In conclusion, our experiment shows that habitat alteration negatively impacts the fitness of burying beetles and, thus, limits their elevational distribution through lowering their population density, which leads to Allee effect and weakens their interspecific competitive ability against flies. Our study, therefore, demonstrates that understanding the synergistic effect of biotic and abiotic factors is crucial for determining the ecological impacts of habitat alteration and conservation
Explore the impacts of river flow and water quality on fish communities
No full text台灣受到先天地理環境及氣候條件之限制，河川坡陡流急，降雨在時空上分布不均，加上颱風豪雨等季節性氣候情況，急驟之降雨易導致河川生態水文環境產生劇烈變化及衝擊。在過去河川流域的研究當中，流量、水質往往有著密切的交互關係，並同時影響著河川生態系統，為了達到永續發展的目的，水資源管理需具備合理與整體之規劃，在開發環境資源時亦能考量與執行生態永續經營之理念為重要的課題之一，因此，本研究藉由探討河川流量、水質及魚類群聚特性之複雜關係，了解彼此間互相影響之機制以尋找改善河川生態系統之方法，進而提升台灣對於河川之水資源經營管理及永續發展之效能。 本研究選定淡水河流域具有較長期(2005~2012)監測之日流量、水質月資料及生態採樣調查資料之新店溪支流為研究區域。本研究根據台灣生態水文指標系統(Taiwan Ecohydrologic Indicator System, TEIS)先將河川流量資料轉換為流態資料(月尺度)，再藉由統計方法分析探討流態、水質及魚類群聚在河川上、下游之差異性，進而透過Gamma Test (GT)篩選流態及水質因子，辨識推估模式輸入因子較佳之組合，以降低模式結構的複雜度，並避免容易產生資料過度描述(over-fitting)的情形，接著利用調適性網路模糊推論系統(Adapted Network-Based Fuzzy Inference System, ANFIS)針對魚類之多樣性指標建置推估模式，結果顯示利用GT所篩選之輸入因子能有效地推估魚類多樣性指標，此外，模式輸入項加入流態因子能獲致更好的推估效果。最後透過規則庫中各輸入項之隸屬度函數探討輸入因子對於河川魚類生態之影響，進一步掌握該流域之生態系統變異，期能作為日後相關水文生態實務管理之參考，以維持河川整體的生態穩定性及永續發展。Subject to the geographic environment and climatic conditions of Taiwan, rivers in Taiwan are of steep slopes and flow into oceans very quickly. Due to the uneven temporal and spatial distribution of rainfall and the severe intensity and short duration of typhoons and storms, sudden rainfall would easily cause huge variations and significant impacts on riverine eco-hydrological environments. The previous research on river basins indicated that river flow and water quality is closely related to each other, which influences river ecosystems simultaneously. To achieve the goal of sustainable development of water resources, rationality and integrity is essential for water resources management while planning to exploit environmental resources in consideration of ecosystem sustainability. Therefore, this study explores the complex relationship among river flow, water quality and fish communities in order to understand the interactive mechanism among each other and develop a methodology suitable for improving river ecosystems; and consequently promotes the management and sustainable development of water resources. In this study, the Xindian River, one of the three major tributaries of the Tamsui River, is chosen as the as study area, which has long-term (2005-2012) daily (river flow) and monthly (water quality) observational data as well as fishery data collected from field surveys. Based on the Taiwan Ecohydrologic Indicator System (TEIS), river flow data is converted into flow regime in a monthly scale. Statistical analyses are then conducted to explore the differences of flow regime, water quality and fish communities between the upstream and downstream areas of the Xindian River. This study next estimates fish diversity indexes by using the Adapted Network-Based Fuzzy Inference System (ANFIS) based on key input factors determined by the Gamma Test (GT), a powerful tool for reducing model complexity of artificial neural networks (ANNs). The results reveal that the constructed model with key input factors selected by the GT can effectively estimate fish diversity indexes, and the estimation performance becomes even better if flow regime can be incorporated as model inputs. Finally, the investigation on the membership functions of the ANFIS can explore the impacts of each input on fish diversity to keep abreast of the variation of the river ecosystem. The results of this study can provide valuable findings as a guiding reference for the practices of eco-hydro system management and the planning of sustainable water resources management of the whole river basin in the future
Fit Fun: A Family Athleisure Company for the Conscious Consumer
No full textNoneThis business plan pertains to an athleisure wear company looking to enter into the US market with eco-friendly, family oriented activity appropriate clothing
Feasibility of data-sharing PROPELLER Diffusion Weighted Image with multiple b-values: a simulation study
No full text多 b 值數據共享式螺旋槳擴散權重磁振影像的可行性將在此論文中被探討。此技術的提出主要將針對螺旋槳式磁振造影取像過程過久之問題進行修正。透過收取不同權重值的槳葉擴散影像並嘗試重建之，影像的取得速度將會依據共享的槳葉數量進行提升。在初步的嘗試中，影像可被成功的重建成高解析度影像，然而k 空間訊號特性將使得這樣的重建方式會於影像上出現假影。假影的詳細成因和降低方法將在本文中被提出。透過此方法，不同擴散能力的組織共存於同一像素內所造成之雙指數訊號衰減將有機會被正確的呈現。The feasibility of Data Sharing PROPELLER MR imaging with multiple b-values is first proposed and evaluated in this thesis. This technique aims to shorten the amount of time when acquiring PROPELLER diffusion weighted images. Preliminary result of this thesis demonstrated that it is possible to combine each under-sampled rotating blades encoded with respect to different b-values together to create high resolution images. The combination process is accompanied with some unwanted artifacts due to data discrepancies between central and outer k-space. However, the reason and the possible strategies to reduce its effects are also proposed. The proposed methodology is able to quantitatively measure the signal behavior of bi-exponential decays