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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

NEURON ADHESION PATTERNING ON POLYMERS BY NEGATIVE-ION IMPLANTATION / 負イオン注入による高分子表面上での神経細胞接着のパターニング / フイオン チュウニュウ ニ ヨル コウブンシ ヒョウメンジョウ デ ノ シンケイ サイボウ セッチャク ノ パターニング

SOMMANI, Piyanuch 25 September 2007 (has links)
学位授与大学:京都大学 ; 取得学位: 博士(工学) ; 学位授与年月日: 2007-09-25 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2865号 ; 請求記号: 新制/工/1421 ; 整理番号: 25550 / Many conventional methods have been used to modify the wettability of the polymeric surfaces for the biomedical applications of the artificial bionic organ. Those methods are the chemical treatment, the ultraviolet (UV) irradiation, the plasma process and the ion implantation. Many artificial bionic organs, for example, an artificial heart, an artificial blood vessel, a device for prevention of thrombosis stent and an artificial endocranium have been developed for the physical or mental disability. For development of the high function of an artificial bionic organ, the data transmission between the brain neuron cells and the external electrical circuit, and the high biocompatible materials for the interface between brain and electrode are required. It is related to the technology of brain-computer interface (BCI), sometimes called a direct neural interface or a brain-machine interface. In case of the brain-controlled devices, the study of the brain memory is necessary. Then, the artificial pattern network of the brain cells cultured on the surface in vitro for simulation of the brain function is the concerned issue. The arrangement of a lot of neuron on a detection electrode is required. So, a formation method of the artificial neural network that arranged a neuron as technology for this purpose is demanded As for the neuron arrangement, there were the reports about the immobilization of neuron by fabrication of the three-dimension structure, and they could be divided into two methods from their manipulation. One is the arrangement with one-by-one manipulation and the other is the arrangement with self-assembly. The former method is the fabrication of many micro-structures and then arranged a neuron in a desired position with one-by-one manipulation to for a neuron network. For the brain memory stimulation, however, the neuron network from more than 10 millions of neurons is required. So, this method is not suitable. The latter is the fabrication of the carbon nanotube pillar to immobilize the neurosphere with self-assembly adhesion. Although this method could be formed the large neuron network, the neurosphere consists of several 1, 000 cells. So, it is very difficult to analyze the mechanism of data transformation. In contrast, by surface modification even if on the same surface to modify a geometric pattern, the cells can adhere along the modified pattern by using single culture on such surface. The neuron will migrate itself to adhere on the pattern. The self-assembly adhesion occur. This method is very useful for the neuron arrangement method. The surface modification of the polymeric materials to pattern the cell adhesion area as a network has been taken place by using many techniques such as the plasma process, the irradiations of UV and X-ray and the ion implantation. The ion implantation technique into the polymeric-material surface has more advantage than the other techniques since its abilities to control the micro-area, and to break down the tight bonding of polymer material. The ion implantation with positive ion without charge neutralization results in a charge-up problem due to the insulating properties of most polymers. This charge-up problem exerts a bad influence on the implantation control of ion dose and ion energy. The negative-ion implantation occurs almost “charge-up free” even if no external charge compensation. Then, the negative-ion implantation into polymeric surface has a very precise control to obtain very fine pattern. So, it is expected to control the adhesion size of about single cells (about several 10 μm). Since this study will be used for the application in the biomedical fields, the ion element should be considered to be harmless for the living body. Then, carbon is selected since it is main component of polymer materials and more familiar to cells. As above described, in this thesis, I use the carbon negative-ion implantation to modify the polymeric surface to obtain the pattern of the neuron with self-assembly-adhesion. As for the polymeric material in the biomedical fields, I selected polystyrene (PS) and silicone rubber (SR). In this research, the fundamental parameters for cell adhesion on the modified surface by carbon negative-ion implantation were described (Chapters 3, 4 and 5). As for the fundamental issue, the wettability relating to the atomic bonding state of the new functional group and the surface morphology (Chapter 3), the protein adsorption (Chapter 4), and also the adhesion of nerve-like cells on the pattern (Chapter 5) were examined. In these chapters, I clarified the relationship among them and the negative-ion implantation. Then, based on these phenomena, I have developed the new application techniques by negative-ion implantation for the adhesion patterning of neuron (Chapters 6 and 7). In the development of these techniques, I have proposed two methods since the neuronal cells required the special base surface to adhere. One is degradation method of the special base surface by which I tried to make an artificial neuron network (Chapter 6). The other is the patterning of the stem cell adhesion and differentiation into neuron with maintaining the adhesion position. So, the neuron patterns were formed on the pattern (Chapter 7). The obtained results are summarized as the following. In Chapter 3, the surfaces of the PS and SR were implanted by carbon negative ions at the energies of 5 – 20 keV and the doses of 1×1013 – 3×1016 ions/cm2. After the implantation, the change in the physical surface properties, relating to the adsorption properties of adhesive proteins, was described. The new atomic bonding, the surface morphology and the wettability were studied by XPS analysis, AFM and contact angle measurement, respectively. XPS analysis showed the formation of new oxygen function groups of hydroxyl and carbonyl on the implanted surfaces from the adsorption of the oxygen in the residual gas and in the moisture in the air on the ion-induced defects. These new bonds refer to the hydrophilicity for the wettability. The ion implantation sputtered and changed the surface morphology of surface roughness in order of several nm that dose not interfere to the protein adsorption and to cell culture. The wettability properties of the C¯-implanted surfaces of SCPS and SR were evaluated by measuring the change in contact angle. At first, the angles were measured by the water drop method. The contact angles of PS measured by water drop method decreased from 91° to 86° for the non-implantation to the implantation, respectively. Those of SR also decreased from 100° to 86°for the non-implantation to the implantation, respectively, even if the main chain bonds in SR are stronger than that in PS. The hydrophilic surfaces of PS and SR were obtained by carbon negative-ion implantation. Then, the contact angles were measured by the air bubble method. The sample was dipped in the water and the bubbles were injected on the surface. Then, the angle was evaluated from the arc circular of the bubble. After dipping in the water for 24 h, the average value of the angles decreased to 64° and to 52° for PS and SR, respectively. The more clearly hydrophilic properties were observed. In Chapter 4, I checked the adsorption properties of the adhesive protein and the poly-D-lysine (PDL) on the implanted surface. Generally, in the cell adhesion, the adhesive proteins exist between the cell surface and the surface. On the cell membrane, cells have specific receptors that anchor to the specific protein. So, the adsorptions of the adhesive proteins are necessary for the cell adhesion. In nature, protein has both hydrophobic and hydrophilic groups. Thus, the ultra hydrophobic and ultra hydrophilic surfaces are not suitable for protein adsorption. The adhesive proteins for the cell adhesion generally prefer to be adsorbed on the hydrophilic surface, which the contact angle is in the range of 40° – 80°. I evaluated the adsorption properties of adhesive protein such as type-I collagen, fibronectin and laminin and that of PDL on the modified surfaces of PS and SR by detecting the nitrogen atom with using XPS analysis. As a result, the adsorptions of the adhesive protein were almost improved with 1.2 – 3.3 times by carbon negative-ion implantation. In Chapter 5, the nerve-like cells of PC12h (rat adrenal pheochromocytoma) were cultured on the C¯-implanted surfaces of PS and SR to find out the fundamental condition for the neuron network formation. As a results, PC12h cells and their neurite outgrowth showed the self-assembly adhesion along the implanted pattern on both of PS and SR. The suitable condition of the ion implantation for the adhesion patterning of PC12h cells was about 1×1015 – 3×1015 ions/cm2. Almost no effect of energy in the range of 5 – 20 keV on the cell adhesion was observed. The effective minimum line width of the implanted region for the adhesion of single cell-body and single neurite outgrowth were about 5 and 2 μm, respectively. In Chapter 6, the brain neuronal cells require the specific surface culture, such as PDL. So, in this chapter, I used PDL coating on the PS and degraded it by the carbon negative-ion implantation. Two kinds of brain neuronal cells were used. One is newborn mouse brain neuronal cells (1 day) and the other is rat embryo brain cortex neuronal cells (16 – 18 days). As a result, obtained the effective ion dose for degradation of the adhesion at 1×1014 ions/cm2. The adhesion patterning of brain neuronal cells on the unmodified pattern of PDL could be achieved by carbon negative-ion implantation. In Chapter 7, I cultured the adult stem cells of rat mesenchymal stem cells (MSC), which has the multipotential to differentiation into many kinds of cell lines, especially into neuron, on the pattern region of the C¯-implanted surfaces of PS and SR. As a results, MSCs showed the self-assembly adhesion along the implanted pattern of PS and SR. Comparing to the adhesion patterning of PC12h cells, the adhesion patterning of MSCs required a lower ion dose to implant on the polymeric surfaces. By culturing with the culture medium supplementing withβ-Mercaptoethanol (BME) at concentration of 1 mM, the MSCs were induced to differentiate into neuronal cells. The adhesion patterning of the neuron-differentiated cells maintained on the implanted region was observed. By staining with anti-neuron-specific enolase, these differentiated cells were neurons. From all investigation, I clarified the change in the physical surface properties after the carbon negative-ion implantation into the polymeric surface and the mechanisms mentioned above. I showed the surface modification to obtain the hydrophilic surface by the ion-induced effect. This hydrophilic surface improved the protein adsorption properties. By using nerve-like cells, the ion implantation affecting to the cell adhesion were clarified. By the implantation through the micro-pattern mask, the cells adhered along the implanted pattern. The cells could adhere on the implanted area that was smaller than the cell size and their neurite also could adhere on the narrowed implanted area. So, I can obtain the self-assembly separation pattern of cell body adhesion and neurite outgrowth. For the application of patterning of real neuron, I coated the special surface with PDL and degraded it from patterning the negative-charge site on it by using carbon negative-ion implantation through a micro-pattern mask. I could pattern and form the neuron network of the brain neuron on the unmodified PDL. On the other hand, for the MSC, I also achieved the adhesion patterning by using carbon negative-ion implantation through a micro-pattern mask, and I succeeded the patterning of the neuron-differentiated cells from the adhered MSC with maintaining their adhesion pattern. As a conclusion, from all these researches, I achieved the cell-self-assembly adhesion and the patterning of the neuron network formation on the polymeric surfaces by using carbon negative-ion implantation. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13394号 / 工博第2865号 / 新制||工||1421(附属図書館) / 25550 / UT51-2007-Q795 / 京都大学大学院工学研究科電子工学専攻 / (主査)教授 石川 順三, 教授 髙岡 義寛, 教授 小林 哲生 / 学位規則第4条第1項該当
2

セメント系薬液注入材の耐久性に関する研究

秋田, 勝次 23 January 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12621号 / 論工博第4066号 / 新制||工||1530(附属図書館) / 29191 / (主査)教授 朝倉 俊弘, 教授 宮川 豊章, 教授 木村 亮 / 学位規則第4条第2項該当
3

酸化ガリウムのホモエピタキシャル成長とn型ドーピングに関する研究

佐々木, 公平 25 July 2016 (has links)
雑誌名: Electron device letters. In reference to IEEE copyrighted material which is used with permission in this thesis, the IEEE does not endorse any of Kyoto University's products or services. Internal or personal use of this material is permitted. If interested in reprinting/republishing IEEE copyrighted material for advertising or promotional purposes or for creating new collective works for resale or redistribution, please go to http://www.ieee.org/publications_standards/publications/rights/rights_link.html to learn how to obtain a License from RightsLink. / 京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第13043号 / 論工博第4144号 / 新制||工||1652(附属図書館) / 33035 / (主査)教授 藤田 静雄, 教授 川上 養一, 教授 木本 恒暢 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
4

増幅および注入ロック用小形D_2Oレーザの単一モード発振

高田, 昇治, 佐々木, 浩一, 高橋, 修, 永津, 雅章, 築島, 隆繁 20 June 1994 (has links)
No description available.
5

高周波プラズマ型荷電粒子源の開発とその応用 / コウシュウハ プラズマガタ カデン リュウシゲン ノ カイハツ ト ソノ オウヨウ

酒井, 滋樹 23 March 2009 (has links)
Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12337号 / 論工博第4015号 / 新制||工||1466(附属図書館) / 27192 / UT51-2009-D552 / (主査)教授 石川 順三, 教授 橘 邦英, 教授 髙岡 義寛 / 学位規則第4条第2項該当
6

内空変位計測による長大海底トンネルの健全性評価に関する研究

深沢, 成年 23 March 2017 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第13090号 / 論工博第4151号 / 新制||工||1675(附属図書館) / (主査)教授 朝倉 俊弘, 教授 木村 亮, 教授 岸田 潔 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
7

ダム基礎岩盤の水理地質特性に即した効率的なグラウチング工法の選定手法に関する研究

吉津, 洋一 25 September 2023 (has links)
京都大学 / 新制・論文博士 / 博士(工学) / 乙第13574号 / 論工博第4211号 / 新制||工||1990(附属図書館) / (主査)教授 岸田 潔, 教授 角 哲也, 教授 高橋 良和 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
8

反射戻り光が動的単一モード半導体レーザのモード分配特性に及ぼす影響の研究

森, 正和 03 1900 (has links)
科学研究費補助金 研究種目:一般研究(C) 課題番号:03650275 研究代表者:森 正和 研究期間:1991-1992年度
9

ポリマーセメント系補修材の開発と無機系複合表面処理工法のASR抑制効果に関する研究

若杉, 三紀夫 24 September 2014 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第12857号 / 論工博第4104号 / 新制||工||1608(附属図書館) / 31537 / (主査)教授 宮川 豊章, 教授 河野 広隆, 准教授 山本 貴士 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
10

運用使用者輸入欄位屬性偵測防禦資料隱碼攻擊 / Preventing SQL Injection Attacks Using the Field Attributes of User Input

賴淑美, Lai, Shu Mei Unknown Date (has links)
在網路的應用蓬勃發展與上網使用人口不斷遞增的情況之下,透過網路提供客戶服務及從事商業行為已經是趨勢與熱潮,而伴隨而來的風險也逐步顯現。在一個無國界的網路世界,威脅來自四面八方,隨著科技進步,攻擊手法也隨之加速且廣泛。網頁攻擊防範作法的演進似乎也只能一直追隨著攻擊手法而不斷改進。但最根本的方法應為回歸原始的程式設計,網頁欄位輸入資料的檢核。確實做好欄位內容檢核並遵守網頁安全設計原則,嚴謹的資料庫存取授權才能安心杜絕不斷變化的攻擊。但因既有系統對於輸入欄位內容,並無確切根據應輸入的欄位長度及屬性或是特殊表示式進行檢核,以致造成類似Injection Flaws[1]及部分XSS(Cross Site Scripting)[2]攻擊的形成。 面對不斷變化的網站攻擊,大都以系統原始碼重覆修改、透過滲透測試服務檢視漏洞及購買偵測防禦設備防堵威脅。因原始碼重覆修改工作繁重,滲透測試也不能經常施行,購買偵測防禦設備也相當昂貴。 本研究回歸網頁資料輸入檢核,根據輸入資料的長度及屬性或是特殊的表示式進行檢核,若能堅守此項原則應可抵禦大部分的攻擊。但因既有系統程式龐大,若要重新檢視所有輸入欄位屬性及進行修改恐為曠日費時。本文中研究以側錄分析、資料庫SCHEMA的結合及方便的欄位屬性定義等功能,自動化的處理流程,快速產生輸入欄位的檢核依據。再以網站動態欄位檢核的方式,於網站接收使用者需求,且應用程式尚未處理前攔截網頁輸入資料,根據事先明確定義的網站欄位屬性及長度進行資料檢核,如此既有系統即無須修改,能在最低的成本下達到有效防禦的目的。 / With the dynamic development of network application and the increasing population of using internet, providing customer service and making business through network has been a prevalent trend recently. However, the risk appears with this trend. In a borderless net world, threaten comes from all directions. With the progress of information technology, the technique of network attack becomes timeless and widespread. It seems that defense methods have to develop against these attack techniques. But the root of all should regress on the original program design – check the input data of data fields. The prevention of unceasing network attack is precisely check the content of data field and adhere to the webpage security design on principle, furthermore, the authority to access database is essential. Since most existing systems do not have exactly checkpoints of those data fields such as the length, the data type, and the data format, as a result, those conditions resulted in several network attacks like Injection Flaws and XSS. In response to various website attack constantly, the majority remodify the system source code, inspect vulnerabilities by the service of penetration test, and purchase the equipment of Intrusion Prevention Systems(IPS). However, several limitations influence the performance, such as the massive workload of remodify source code, the difficulty to implement the daily penetration test, and the costly expenses of IPS equipment. The fundamental method of this research is to check the input data of data fields which bases on the length, the data type and the data format to check input data. The hypothesis is that to implement the original design principle should prevent most website attacks. Unfortunately, most legacy system programs are massive and numerous. It is time-consuming to review and remodify all the data fields. This research investigates the analysis of network interception, integrates with the database schema and the easy-defined data type, to automatically process these procedures and rapidly generates the checklist of input data. Then, using the method of website dynamic captures technique to receive user request first and webpage input data before the system application commences to process it. According to those input data can be checked by the predefined data filed type and the length, there is no necessary to modify existing systems and can achieve the goal to prevent web attack with the minimum cost.

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