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Closure to Discussion of Unit Commitment by LaGrangian Relaxation and Genetic algorithms
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The Simulation Platform for DC Micro-Grid
No full text本文主旨在建立一個直流微電網模擬測試平台，該系統包含了風力發電機、太陽能光電系統與燃料電池等分散式能源，鋰離子電池、超級電容器等儲能元件，以及三相市電換流器。該直流微電網模擬測試平台亦可用來開發以及驗證直流微電網之能量管理策略。
該系統中之三相市電換流器具備了低電壓穿越(Low Voltage Ride Through, LVRT)的功能，當市電端因為電力系統發生故障(人為因素或是天災)，導致市電端電壓跌落時，直流微電網依然能與市電併聯正常運作。
此模擬測試平台以數學模式描述各分散式電源及儲能元件特性，並以電腦軟體Matlab/Simulink建立等效模型，來進行直流微電網之模擬。This test bed is built by mathematical models in Matlab/Simulink. It is a platform for users to clearly handle the information of the DC micro-grid. This thesis presents a DC micro-grid simulation platform which can help designers to decide the capacity of energy storage components of micro-grid, and develop the energy management strategy for DC micro-grid. It can also help to verity the operational principle of DC micro-grid with/without AC grid. The three-phase grid-connected inverter is equipped with the LVRT (Low Voltage Ride Through) capability. A human-machine interface is built in LabVIEW which is a platform for users to clearly handle the information of the micro-grid. Some examples are shown in this thesis
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Regulation of glutathione synthetase gene in Caenorhabditis elegans by heavy metals
No full textGlutathione synthetase (GS)為催化γ-glutamylcysteine以及glycine兩者生合成為glutathione (GSH)的重要酵素。GS-1是在C. elegans 中被預測出來與GS同源的基因。本篇研究目的旨在探討GS-1於抵抗砷及鎘的暴露所誘發之氧化壓力中所扮演的角色。本研究利用RNA干擾技術、基因轉殖的C. elegans 、以及mRNA表達之分析方法探討GS-1在C. elegans 體內的功能及表現。研究結果顯示，經由GS-1 RNA干擾的C. elegans，即使在正常的生長環境下也會產生許多不同的效應，其中包括其生命週期被大幅的縮短、存活率的降低、成蟲率的降低、以及形體外型的改變，而當此C. elegans生長於含有砷及鎘的環境中時，上述的效應則更加的顯著。這些結果證明了GS-1為C. elegans之生長、存活、及生命週期的必要基因，而且對於抵抗砷及鎘所誘導的氧化壓力為不可或缺的重要角色。本研究結果進一步發現C. elegans於不同的生長階段之GS-1 mRNA會有不同程度的表現，而且在L4- stage具有最高的表現量。另外，於基因轉殖的C. elegans的觀察之中也發現當C. elegans受到熱擊 (heat shock)、 巴拉刈 (paraquat)以及鎘暴露等不同來源的壓力之下，基因轉殖的C. elegans會被激發出明顯的螢光訊號，而對於其他的金屬則闕如。本論文的研究結果證明了GS-1為C. elegans生長發育和生命週期的必須基因，更顯示GS-1於抵抗砷及鎘所誘導的氧化壓力中扮演了十分重要的角色。Glutathione synthetase (GS) catalyzes the ATP-dependent synthesis of GSH from γ-glutamylcysteine (γ-Glu-Cys) and glycine. It is predicted that GS-1 is the C. elegans ortholog of GS. To investigate the protective role of cellular GSH against arsenic- and cadmium-induced oxidative stress in C. elegans, we examined the effect of GS-1 in response to arsenic and cadmium exposure. The functional importance of GS-1 in C. elegans is investigated by RNA interference (RNAi) mediated (GS-1-dificent) worms. Under normal growth conditions, pleiotropic phenotypes of GS-1 (RNAi) worms were observed, including shorten life span, decreased survival rate and adult percentage, and morphological changes, suggesting that GS-1 is essential for development and viability. These observed effects were more profound while GS-1 (RNAi) worms were grown in the presence of As (III) and Cd (II), indicating that GS-1 is required C. elegans' defense against As (III) and Cd (II) toxicity. GS-1 mRNA expression regulated by different metals in vivo and in vitro were examined by transgenic C. elegans and real-time RT-PCR analysis. GS-1 mRNA varied in different developmental stages of worms and the highest level of GS-1 mRNA was observed at L4-stage. Heat, paraquat, and Cd (II) significantly induced GS-1 expression with the highest level GFP signal, whereas other metals induced less extent. In this study, our results indicated that GS-1 plays an important role in C. elegans’ development and life span, and it is required for the protection of C. elegans against arsenic- and cadmium-induced oxidative stress.TABLE OF CONTENTS
口試委員會審定書 I
The approval Sheet II
致謝 III
中文摘要 V
ABSTRACT VI
TABLE OF CONTENTS VIII
LIST OF FIGURES X
LIST OF TABLES XI
Abbreviations XII
CHAPTER 1 INTRODUCTION 1
1.1 Overview 1
1.2 Arsenic 1
1.3 Cadmium 3
1.4 Oxidative Stress 4
1.5 Glutathione and Glutathione Synthetase 8
1.6 Caenorhabditis elegans 13
1.7 Glutathione Synthetase Homolog in C. elegans 14
1.8 Purpose of Study 14
CHAPTER 2 MATERIALS & METHODS 16
2.1 Chemicals 16
2.2 Strains, Clones, and Worm Culture 16
2.3 RNA Interference 16
2.4 Culture and Isolation of C. elegans Exposed to Various Stressors 17
2.5 Synchronization of C. elegans 18
2.6 RNA Isolation and real-time RT-PCR 18
2.7 Effect of Transgenic C. elegans 21
2.8 Life Span Assay 21
2.9 Intracellular GSH Measurement 22
2.10 Statistical Analysis 23
CHAPTER 3 RESULTS 24
3.1 Structure and Organization of gs-1 24
3.2 RNA Interference Analysis 28
3.2.1 Phenotypic analysis of wild type worms with GS-1-deficient 28
3.2.2 As(III) and Cd(II) hypersensitivity of GS-1(RNAi) worms 35
3.2.3 Screening of putative transporter gene using GS-1(RNAi) 40
3.2.4 Down-regulation of GS-1 suppresses longevity in C. elegans 42
3.3 Analysis of GS-1 mRNA Expression level Affected by Stressors 45
3.3.1 Regulation of GS-1 mRNA expression level by As(III), As(V), and Cd(II) 45
3.3.2 Regulation of GS-1 mRNA expression by As(III) associated with development 46
3.4 Effect of Various Stressors on gs-1 Transcription in Transgenic C.elegans 47
CHAPTER 4 DISCUSSION 55
4.1 Characterization of C. elegans GS-1 55
4.2 Down-regulation of GS-1 Reduces C. elegans Life Span 57
4.3 GS-1 mRNA expression affected by various metals Exposure 58
4.4 How As(III) and Cd(II) are exported in C. elegans 61
CHAPTER 5 CONCLUSION 64
REFERENCES 66
LIST OF FIGURES
Figure 1-1 Pathway for the biosynthesis of glutathione 9
Figure 1-2 The roles of GSH were played in oxidative stress managerments 12
Figure 3-1 Schematic diagram and exon/intron organization of gs-1 25
Figure 3-2 Multiple alignment of the predicted amino acid sequence of C. elegans glutathione synthetase with other known GS amino acid sequence. 26
Figure 3-3 Hydropathy profile of the GS-1 amino acid sequence. 29
Figure 3-4 Putative upstream regulatory elements in gs-1 30
Figure 3-5 Effect of GS-1 (RNAi) on C. elegans 32
Figure 3-6 GS-1 (RNAi) affects reproduction of worms 33
Figure 3-7 Morphologic change associated with GS-1 RNAi 34
Figure 3-8 RNAi effect in growth delayed of C. elegans 36
Figure 3-9 RNAi effect in C. elegans of As (III) 38
Figure 3-10 RNAi effect in C. elegans of Cd (II) 39
Figure 3-11 RNAi effect of N2 and VC287 (hmt-1 mutant) in C. elegans 41
Figure 3-12 Lifespan reduction by GS-1-dicifent and mediated with As (III) 43
Figure 3-13 Lifespan reduction by GS-1-dicifent and mediated with Cd (II) 44
Figure 3-14 GS-1 mRNA level by various heavy metals 48
Figure 3-15 The expression of GS-1 during C. elegans development with As (III)..…………………………………………………………………...50
Figure 3-16 Expression pattern of transgenic C. elegans 52
Figure 3-17 Expression pattern of transgenic C. elegans of Cd (II) exposure 53
Figure 3-18 Expression pattern of transgenic C. elegans 54
LIST OF TABLES
Table 2-1 Primers used for real-time PCR 2
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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