Genetic analysis of PARK2 gene in Korean patients with Parkinson's disease

박인원 忠南大學校 新藥專門大學院 2016 국내박사

Mutations in PARK2 are considered a common cause of Parkinson’s disease (PD). To assess the frequency of PARK2 mutations in the Korean population, we screened the PARK2 gene in 83 Korean PD patients: two young onset (YO, ≤49), 32 middle onset (MO, 50-69) and 49 late onset (LO, 70). Detection of the point mutations was performed by direct sequencing of the PARK2 exons, and exonic rearrangements were analyzed using multiplex ligation-dependent probe amplification (MLPA). Five known PARK2 variants were identified in 53 (63.9%) of the Korean PD patients: two missense mutations (Y267H and M458L) and three polymorphisms (S167N, L272I and V380L). We also found an increased frequency of PARK2 variants in PD patients and a lowered PD age at onset (AAO) in those having two variants, suggesting that the genetic variation in PARK2 gene might be a genetic risk factor of PD in Korean population.

공동주택 지하주차장 평면형태 및 환기구의 배치에 따른 공기유동에 관한 연구

박성원 부산대학교 2010 국내석사

The study on the airflow based on the array of ventilator and plan of the underground parking lot in apartment As demands of the residents have been variously changing according to the construction of the apartment house and the fast economic growth, the construction companies spurs the development of the apartment house flavored with environmental friendly factors. Also because of the multiple apartment project, the basement car park alone can not handle the rapid growth of the vehicles and the resident puts more and more emphasis on securing car park space for the freedom from the vehicles on the ground and for the safety of their children. Recently, as the interest about natural energy, the tendency minimizing the mechanical energy also appears. According to this trend, there has been growing attempts in order to apply the environmental friendly technologies to the apartment house. But the reality is that the systems doesn't virtually function well because the existing mechanical systems are applied. Consequently, the deterioration of the air and the brightness in the basement car park exacerbates the environments of the basement car park. And the study on the feasibility of the natural ventilation according to the unit-plan type of the basement car park and the performance of the skylight, is still insignificant. Thus, in this study, we intend to simulate, through the CFD, the air current by natural driving power by classifying the existing basement car parks into the unit-plan type and the direction of the vehicle traffic. Through classifying the existing basement car parks by the type of vehicle traffic that is the type of arrangement such as one-way or bidirectional traffic and deploying the ventilating openings by 3 types which enables the skylights, linked the ground for the purpose of collecting the light, play the role of ventilation at the same time, we forecast the air current of the basement car park by using CFD(Computational Fluids Dynamics) and, based on that, suggest the plan to improve the ventilating function of the basement car park by utilizing the natural ventilation. In this study, we research the general theories, that is 'the ventilation theory of underground space and the test method of ventilating performance' and interpret, through CFD, the air current of the target models according to the layout of the ventilation openings based on mean of air age and air exchange effectiveness by using computer simulation. As a result, we draw the conclusion as follows: (1) In respect of the air age according to the type of the vehicle traffic such as one way traffic and bidirectional traffic, the bidirectional traffic shows 30,405 seconds while 14,070 seconds in one way traffic indicating that the one way traffic abates by more than 50%. Therefore, the air of the basement car park with one way traffic has superior air quality because of its' shorter air age. (2) In case of the existing basement car parks, Case A' air exchange rate is 4.44 while 7.76 times/h in Case B and 1.94 times/h in Case C. It appears comparatively small in Case C. We can draw the conclusion, through this finding, that the placement of several natural ventilators in the middle and on the edge is more effective than the placement of the natural ventilator with big area in the middle when placing natural ventilator. (3) In case of Case B where the installation is in the middle and on the edge of the basement car park, it appears excellent in both the air exchange and the air age, but the effective area of the space on the ground abates. There requires a plan for the placement accordingly. (4) In case of Case C where the circular air-vent with the smallest area of air-vent is installed, the velocity of air current appears the fastest. Thus, it seems that there requires the research on the appropriate size and the layout plan of the circular air-vents for the purpose of the increase of effective space on the ground. It is also necessary to comprehend the appropriate locations in order to improve the performance of the natural ventilation, through examining the characteristic of the air current according to the type of ventilating openings installed in the basement car park, the velocity of the current, the pressure distribution and the installation of the auxiliary equipments for the natural ventilation.

How does the national park management deliver their services? The perspective of service marketing focused on gunung gede pangrango national park, Indonesia

Maulana, Firman 서울시립대학교 국제도시과학대학원 2018 국내석사

인도네시아에 설립된 가장 오래된 국립공원 중 하나인 구눙 게대 빵랑오 국립공원(GGPNP)은 관광 개발의 기초로 생태관광을 선택했다. 생태관광과 관련된 모든 혜택에 관계 없이 미래에 최적의 이익을 얻으려면 여전히 해결해야 할 과제가 있다. 정부기관으로서 GGPNP는 방문객에게 서비스를 제공하는 관광 활동을 지원하는 단순한 관리 이상의 또 다른 역할을 한다. 최근의 사실은 국립공원에 방문하는 관광객 수가 여전히 적다는 것을 보여주며 그 이유 중 하나는 국립공원에서 마케팅에 대한 관심이 낮기 때문이다. 국립공원은 또한 성과 중 하나인 방문 관광객 수에 대한 목표를 달성해야 하지만 GGPNP의 경영진은 서비스 마케팅을 시행하여 국립공원을 홍보하는 방법에 주목하기 시작해야 한다. 이러한 이유로 본 연구는 서비스 마케팅 관점에서 GGPNP가 서비스를 제공하는 방법을 조사하기 위해 실시되었다. 또한 이 논문은 생태관광 원리를 강조하는 경영진 측면과 인지된 서비스 성과 차원을 강조하는 방문객 관점에서 서비스 마케팅의 3가지 요소(인력, 물리적 증거, 프로세스 관리)를 탐구한다. 조사 결과에 따르면 GGPNP의 서비스 마케팅 구현은 전반적으로 중간 수준이다. 이는 GGPNP가 이미 표준 서비스 마케팅을 수행하지만 마케팅 가치를 높이기 위해 해결하고 개선해야 할 몇 가지 사항이 있다는 것을 의미한다. 인적 요소의 경우 GGPNP는 방문객에게 더 나은 서비스를 제공하기 위해 더 많은 인력을 충원하고 더 많은 교육을 제공해야 한다. 물리적 증거 요소의 경우 방문객은 GGPNP가 국립공원 지역에 머무는 동안 방문객에게 더 많은 지식과 편의를 제공하기 위해 국립공원 지역에 정보 표지판과 위생 시설을 개선하거나 추가해야 한다고 생각한다. 마지막으로, 프로세스 관리 요소에서 GGPNP는 더 많은 절차를 추가하고 고객 평가, 방문 우선순위 시민에 대한 대우(노인, 임산부, 장애인, 어린이), 방문객에게 피드백을 제공하는 방식에 대해 구체적인 사항을 추가해야 한다. GGPNP의 경영진에게 이 결과가 의미하는 바는 특히 인도네시아에서 국립공원의 서비스 마케팅에 대해 논의하는 이전 연구가 없었기 때문에 공식적인 계획 전략을 위한 마케팅 참조자료와 디딤돌을 제공하는 것이다. 또한 훌륭한 서비스 마케팅을 시행함으로써 장기적으로 국립공원을 방문하여 보존 메시지를 받고 환경에 대한 소속감을 높일 수 있는 사람들이 더 많아질 것이다. Gunung Gede Pangrango National Park (GGPNP) one of the oldest national parks established in Indonesia has chosen ecotourism as the basis of their strategy in developing tourism. Regardless of all of the benefits that come with ecotourism, there are challenges that are still need to be addressed to gain optimum benefit in the future. As a government agency, GGPNP has another role than just mere conservation which is supporting tourism activities which mainly about delivering a service to its visitors. The recent data shows that the number of tourist arrival to the national park is still low, and one of the reasons is the low interest of marketing for a national park. While the national park also needs to achieve the target for tourist arrival as one of their performance, the management of GGPNP needs to start their attention on how to market the national park through the implementation of service marketing. Due to these reasons, this research was conducted to examine how the GGPNP delivers their services from the perspective of services marketing. In particularly, this thesis explores the three elements of services marketing (personnel, physical evidence, and process management) from the perspective of management which emphasizes ecotourism principles and the perspective of visitor which emphasizes on perceived service performance dimension. The results of this survey show that as overall the implementation of service marketing in GGPNP is at a moderate level. This means that GGPNP already perform standard service marketing but there are several things that need to be addressed and improved to increase their marketing value. From the personnel element, the GGPNP need to consider adding more personnel and provide them with more training in order to deliver better services to the visitor. For the physical evidence element, the result also shows that the visitor thinks that GGPNP needs to improve or add more information signage and sanitary facilities in the national park area to give more knowledge and comfortability toward visitor during their stay in the area of national park. Lastly, from the process management element shown that GGPNP need to add more procedure and put more specific details on customer evaluation, treatment for priority citizen (elderly, pregnant woman, disabled person, and children) that come to visit, and how they provide their feedback to the visitor. This research is expected to serve as a stepping stone and reference on marketing and planning strategies of GGPNP since there was no previous research that discusses service marketing in the national park especially in Indonesia. Furthermore, by implementing good services marketing it is expected that for long-term outcome there will be more people to visit a national park to receive the message of conservation and hence increase their sense of belonging toward the environment.

Adequacy evaluation of urban park provision considering accessibility and amenity by age and gender cohorts

박시진 한양대학교 대학원 2022 국내석사

Characterization and evaluation of the gene expression profile for nontuberculous mycobacterial pulmonary disease

박영목 Graduate School, Yonsei University 2024 국내박사

Spatio-Temporal Patterns of Human-wildlife Conflict in Bardia National Park, Nepal

PAUDEL, Prabin University of Seoul, International School of Urban 2021 국내석사

지구 생태계의 균형을 이루기 위해서는 야생 생물 보존이 필수적이다. 하지만 야생 동물이 인간에게 피해를 입히면 인간은 그에 대한 복수로 야생 동물을 살상한다. 따라서 생태계 및 인간이 영위하는 생활의 지속 가능성을 위해서는 충돌을 최소화해야 한다. 인간과 야생 동물의 충돌은 바르디아 국립 공원(Bardia National Park)의 주요한 해결 과제이다. 효과적인 충돌 관리를 위해서는 구체적인 시공간 정보가 필수적이다. 그렇기 때문에, 본 연구에서는 바르디아 국립 공원의 완충 지대에서 11년(2010~2020) 동안 발생하여 기록된 충돌의 시공간적 분포를 조사하였다. 데이터 분석에는 기술 및 추론 통계를 사용하였다. 분석 결과에 따르면 기록된 충돌 횟수가 매년 증가하고 있다. 평균적으로 연간 806 건의 충돌이 기록되었다. 이 보호 구역에서 발생한 충돌의 주요 대상 종은 코끼리와 표범인데, 충돌의 59%가 남부 지역에서 기록되었다. 인간과 코끼리의 충돌 중 60% 이상이 8월, 9월, 10월 및 11월에 발생했다. 충돌이 가장 빈번한 계절은 종마다 다르지만, 코끼리, 표범, 호랑이 및 멧돼지의 경우 충돌의 계절적 분포가 유의미하다. 조사 대상 기간 동안의 손실 평가액 중 37%만이 보조금 형태로 지급되었다. 보조금을 받기까지의 과정도 길다. 따라서 지역을 바탕으로 주요 충돌 종을 관리하기 위한 월간 일정이 필수적이다. 초식 동물의 입맛에 덜 맞는 대체 작물을 재배하고 육식 동물의 침입을 막을 수 있는 축사를 장려하는 것이 필요하다. 전기 울타리를 설치하고 유지하며 대체 생계 수단을 제공함으로써 사람들의 삼림 출입을 줄이는 것 또한 중요하다. 이에 더해, 지역 사회를 대상으로 야생 동물의 행동에 대한 지식을 제공하고 교육을 실시하는 또한 바르디아 국립 공원 내에서의 충돌 사고를 축소하는 데 도움이 될 것이다. 주요어: 인간과 야생 동물의 충돌, 시공간 분포, 바르디아 국립 공권, 완충 지대 Human-wildlife conflict is one of the major conservation challenges. Detail spatial and temporal information is essential for effective conflict management. Therefore, this study examines the distribution of conflicts based on space and time for eleven years (2010 to 2020) in the buffer zone of Bardia National Park. Descriptive and inferential statistics were used to analyze the data. The result shows that the number of human-wildlife conflicts is increasing annually. Where on average, 806 conflicts per year were recorded. Elephant and leopard are the major conflicting species in this protected area, and 59 % of the conflict was recorded in the southern regions. More than sixty percent of human-elephant conflicts are recorded in August, September, October, and November. Major conflicting seasons vary with the species, where the distribution of conflict is significantly varied with the seasons for elephant, leopard, tiger, and wild boar. Attack due to carnivore is significantly higher in the new moon phase periods. Only 37 % of the evaluated loss was paid to the victim as a relief. A monthly calendar for the management of major conflicting species is essential. Farming of alternative crops that are less palatable for the herbivores and promoting predator-proof livestock shelter is needed. Where construction and maintenance of electric fences and reduction of dependency over forest resources by providing alternative sources of livelihood are crucial. Furthermore, providing knowledge and training about wildlife behavior to the local community will reduce the conflict and increase the harmony between people and wildlife.

First-Principles Characterization of Transition Metals on Oxide Films

Park, Jinwoo University of Seoul 2010 해외박사

Oxide-supported metal clusters and thin films have attracted a great deal of interest due to their importance in a wide range of technological applications, such as heterogeneous catalysis, gas sensors, corrosion-protective coatings, photovoltaic devices, and microelectronics. The adsorption, growth, and electronic characteristics of metal atoms adsorbed on oxides are of special interest, because these factors are supposed to help design and optimize methods for controlling processes concerning the desired chemical reaction and product. In this thesis, we performed ab initio electronic structure calculations to study the interactions of metal adatoms with ionic oxide atoms involving regular oxide surface atoms, surface oxygen defects like Fs centers, and metal supports. As an oxide, an MgO(001) surface, a prototype of an ionic oxide surface, was chosen here. All calculations were carried out using the density functional theory (DFT). First, a systematic approach was employed to investigate the adsorption geometries and electronic structures of late transition series (Cu, Ag, Au, Ni, Pd, and Pt) on ideal defect-free MgO(001) surfaces. For the above elements, the adsorption geometries, diffusion, and associated electronic structures were examined. Our calculations showed the favorable adsorption of the transition metal (TM) adatoms on top of the surface O atom. Further analysis showed that the TM-induced states formed in the gap region of MgO(001) vary significantly with the adsorption geometries. The DFT calculations have been also applied to investigate the adsorption of the TM adatoms (Cu, Ag, Au, Ni, Pd, and Pt) on defective MgO(001) surfaces with Fs centers as surface defects of oxides. The TM adatoms were found to favorably bind on the Fs centers. From the calculated adsorption structures and electronic structures, we carried out a systematic comparative analysis of the interactions of the metal adatoms with the surface oxygen vacancy and the regular surface oxygen atom of MgO(001). Finally, the adsorption of metal adatoms (Au and Pd) on Fe-supported ultrathin MgO(001) films was studied. Experimentally, it is well known that MgO films are epitaxially grown on Fe(001) due to their favorable physical properties. As such, the Fe/MgO/Fe junctions have been used as a system for magnetic tunnel junctions (MTJs) with huge tunneling-magnetoresistance (TMR) values. Interestingly, our calculations showed that the MgO/Fe(001) films we propose in this work can be used as a viable thin oxide model system. An analysis of the electronic structures in the systems reveals the negative charging even for Pd adatoms with a lower electron affinity. This indicates that the Fe substrate supporting the MgO films significantly influences charge and/or spin states of the metal adatoms. The physical origin of the negative charging of Pd was also discussed. These calculations demonstrate the importance of the interactions of the metal adatoms with underlying oxides for controlling the electronic and chemical properties of metal adatoms, such as charge and spin states.

Advanced ferroelectric memory technology on the van der waals material platform for in-memory computing

Park, Sangyong Sungkyunkwan University 2023 국내박사

전통적인 폰 노이만 방식의 컴퓨터는 데이터 저장공간과 처리공간이 분리되어 데이터를 처리하기 때문에 각 유닛간 데이터의 이동하는 과정이 필요하다. 하지만 각종 정보 기기와 서비스의 발달로 데이터의 크기가 증가함에 따라 연산 보다는 데이터의 이동이 데이터의 처리에 병목이 되고 있다. 이 문제를 해결하기 위하여 메모리 장치에서 연산, 처리까지 진행하는 인메모리 컴퓨팅이 제안되었다. 인메모리 컴퓨팅 구조에서는 데이터 이동에 소모되는 에너지를 최소화되고 크기가 크고 복잡한 데이터를 처리하기에 적합하여 차세대 구조로 관심을 받고 있다. 인메모리 컴퓨팅은 메모리 소자에서 저장과 연산이 모두 이루어지기 때문에 빠른 동작 속도와 안정적인 메모리 특성이 같이 요구된다. 본 논문에서는 인메모리 컴퓨팅에 사용될 새로운 동작 개념을 가지는 두 가지 강유전 메모리 소자를 소개한다. 두 소자는 모두 반데르발스(van-der-Waals) 물질을 기반으로 만들어졌으며 강유전 물질로 α-In2Se3 를 사용하였다. 반데르 발스 물질을 건식이동(Dry transfer) 방식으로 적층 하여 저온 공정으로 깨끗한 표면을 가지는 강유전 메모리 소자를 구현하였다. 첫 번째 소자는 강유전 막질을 전기적으로 고립시켜 전하를 저장하며 동시에 강유전 스위칭 동작을 하는 이중 동작 강유전 소자이다. α-In2Se3의 고유한 특성인 반도체 특성 (Eg=1.3 eV) 과 강유전 특성을 이용하였다. 저장되는 전하의 종류와 양에 따라 강유전 부유층의 전기적 에너지가 변화하여 강유전 스위칭 동작영역을 조절할 수 있다. 이러한 특성을 이용하여 넓은 동작 범위에서 전도도를 연속적으로 변화시킬 수 있다. 강유전 스위칭의 빠른 동작 속도와 낮은 동작 전압을 가지며 동시에 플래시 메모리의 안정적인 메모리 동작으로 전압 구간을 조절할 수 있는 것이 특징이다. 이를 이용하여 메모리 어레이에서 발생하는 산포를 균일하게 조절할 수 있음을 시뮬레이션을 통해 검증하였다. 또한, 연속적이고 넓은 전도도 대역대가 합성곱 신경망(CNN)에서 패턴 인식 정확도 향상에 효과적임을 검증하였다. 두번째 소자는 α-In2Se3의 수직 방향 잔류분극이 수평 방향 잔류분극과 연동되는 고유한 특징을 이용하여 강유전 물질의 측면에서 수평방향 전기장을 인가하여 강유전 메모리 소자를 동작시키는 측면 게이트 강유전 메모리 소자(LG-FeFET)이다. 수평 방향 전기장에 의한 분극이 수직 방향 전기장에 의한 분극보다 메모리 윈도우에 크게 기여함을 구현된 소자로 검증하였으며 분극의 연동 현상과 각 분극의 저장 유지 특성을 PFM과 KPFM 을 통하여 자세히 분석 하였다. 높이 방향의 축소가 중요한 적층형 메모리 구조에서 LG-FeFET을 적용한 3차원 적층형 메모리 구조를 디자인하여 제안하였고 실험적으로 2층으로 적층된 소자에서 곱셈 누산기 동작(MAC operation)을 구현하였다. 마지막으로 수직, 수평 방향에 의한 메모리 윈도가 인메모리 컴퓨팅의 정확도에 미치는 영향을 합성곱 패턴인식 시뮬레이션을 통하여 검증하였다. In-memory computing architecture, which stores and processes data in memory units, has emerged as a promising alternative to the traditional von-Neuman computing architecture because the new approach has the potential to eliminate the energy consumption caused by accessing and moving big data. The key part of the in-memory computing architecture is the performance of the memory device. The fast operation speed for computing tasks and stable memory characteristics for storage are essential characteristics. In this paper, two ferroelectric memory devices with new operational concepts are introduced for the application to in-memory computing. Both ferroelectric memory devices are built based on the van der Waals (vdW) material platform, and α-In2Se3 is used as a ferroelectric material. The vdW material platform allows clean surfaces, low-temperature processes, and thin films. The first device is a ferro-floating memory (FFM) which operates in dual mode. FFM uses an electrically isolated ferroelectric layer for both the ferroelectric switching and the charge storage at the same time. Due to the difference in the operation voltages, FFM operates as a ferroelectric memory in the low voltage range and as a floating gate flash memory in the high voltage range. In other words, FFM has both advantages of ferroelectric memory (fast operation speed) and flash memory (stable memory characteristics). Moreover, FFM can change the operation voltage region of the ferroelectric switching depending on the type and quantity of charges stored in the ferro-floating layer. The feature of the reconfigurable operation voltage was applied to the variation controlling of the threshold voltage in the memory array and to the wide range conductivity. The applications were emulated in pattern recognition neural network simulations. The second device is a laterally gated ferroelectric memory device (LG-FeFET). The LG-FeFET utilizes the interlocking effect of α-In2Se3 between the in-plane (IP) and the out-of-plane (OOP) directional polarizations. The gate of the device is placed on the lateral side of the ferroelectric material and operates ferroelectric switching by applying an IP directional electric field. The interlocking effect was confirmed with KPFM. Furthermore, the dependence of the direction of the electric field on the ferroelectric switching was confirmed by comparing the size of the memory window. The IP directional electric field shows a significantly larger memory window than the OOP directional electric field. A three-dimensional stacked memory structure was proposed, and the MAC operation was implemented in the two-tier stacked device with LG-FeFET devices. Finally, the advantages of the LG-FeFET were compared in an image recognition simulation with a convolutional neural network (CNN).

(A) study of logic implemented computation demonstrated by DNA algorithmic self-assembly

Park, Suyoun Sungkyunkwan University 2022 국내박사

Although structural DNA nanotechnology is a well-established field, computations performed using DNA algorithmic self-assembly is still in the primitive stages in terms of its adaptability of rule implementation and experimental complexity. Owing to its high information density, energy efficiency, and massive parallelism, DNA computing has undergone several advances and made significant contributions to nanotechnology. Firstly, we discuss the feasibility of constructing an M-input/N-output logic gate implemented into simple DNA building blocks. To date, no experimental demonstrations have been reported with M > 2 owing to the difficulty of tile design. To overcome this problem, we introduce a special tile referred to as an operator. We design appropriate binding domains in DNA tiles, and we demonstrate the growth of DNA algorithmic lattices generated by eight different rules from among 256 rules in a 3-input/1-output logic. The DNA lattices show simple, line-like, random and mixed patterns, which we analyze to obtain errors and sorting factors. The errors vary from 0.8% to 12.8% depending upon the pattern complexity, and sorting factors obtained from the experiment are in good agreement with simulation results within a range of 1 ~ 18%. Notably, arithmetic calculations implemented by multiple logic gates such as adders and subtractors have received much attention because of their well-established logic algorithms and feasibility of experimental implementation. Although small molecules have been used to implement these computations, a DNA tile-based calculator has been rarely addressed owing to complexity of rule design and experimental challenges for direct verification. Secondly, we construct a DNA-based calculator with three types of building blocks (propagator, connector, and solution tiles) to perform addition and subtraction operations through algorithmic self-assembly. An atomic force microscope is used to verify the solutions. Although logic implementation using DNA molecules is well established in binary systems (base value of 2) via decoration of hairpin structures on DNA duplexes, systems with base values of >2 (e.g., 3, corresponding to a ternary system) are rarely discussed owing to the complexity of the design and the experimental difficulties with DNA. Thirdly, DNA rule tiles that participate to form algorithmic DNA crystals exhibiting the ternary representation of an N (N = 1 or 2)-input and 1-output assembly are conceived. The number of possible algorithmic patterns is 3^((3^N)) in the ternary N-input and 1-output logic gate. Thus, the number of possible rules is 27 (=33) for a 1-input and 1-output algorithmic logic gate and 19638 (=39) for a 2-input and 1-output algorithmic logic gate. Ternary bit information (i.e., 0-, 1-, and 2-bit) is encoded on rule tiles without hairpins and with short and long hairpins. We construct converged, line-like, alternating, and commutative patterns by implementing six specific rules for the 1-input and 1-output gate and an ascending line-like pattern for the 2-input and 1-output gate. Specific patterns generated on ternary-representing rule-embedded algorithmic DNA crystals are visualized via atomic force microscopy, and the errors during the growth of the crystals are analyzed (average error rates obtained for all experimental data are <4%). Our method can easily be extended to a system having base values of >3. Multiple models and simulations have been proposed and performed to understand the mechanism of the various pattern formations existing in nature. However, the logical implementation of those patterns through efficient building blocks such as nano-materials and biological molecules is rarely discussed. Lastly, we adopt a cellular automata model to generate the simulation patterns and experimental patterns obtained from DNA lattices similar to the discrete horizontal brown-colour line-like patterns on the bark of the Zelkova serrata tree, known as lenticels (observation patterns). simulation patterns and experimental patterns are generated through the implementation of six representative rules in 3-input/1-output algorithmic logic gates. The experimental patterns obtained through DNA algorithmic self-assembly are visualised by atomic force microscopy. Three different modules (A, B and C) are introduced to analyse the similarities between the simulation patterns, experimental patterns and observation patterns of Zelkova serrata lenticels. Each module has unique configurations with specific orientations allowing the calculation of the deviation of the simulation patterns and the experimental patterns with respect to the observation patterns within each module. The findings show that both the simulation pattern and the experimental pattern with module B provide relatively similar Zelkova serrata lenticel-like patterns than others, both quantitatively and qualitatively. Our method provides a potential platform for the construction of various types of DNA algorithmic crystals (such as flip-flops, encoders, and multiplexers) by embedding multiple logic gate operations in the DNA base sequences. In addition, DNA algorithmic assembly provides a novel perspective for the construction of various complex natural patterns. DNA 는 유전 정보를 후손에게 전달하는 매개체의 역할과, 다양한 형태의 나노 구조물을 제작하는 재료의 역할 또한 수행한다. 이러한 구조적 DNA 나노기술분야는 많은 연구를 통해 확립되어 있지만, DNA 알고리즘 자가조립을 이용하여 수행하는 계산은 규칙 구현의 적응성과 실험 복잡성의 측면에서 여전히 초기단계에 머물러 있다. DNA 컴퓨팅은 높은 정보 밀도, 에너지 효율성 및 대규모 병렬 처리로 인해 여러 가지 발전을 거쳤고 나노 기술에 상당한 기여를했다. 본 학위 논문은 DNA 알고리즘 자가조립의 특성을 이용하여 논리를 DNA 구조물에 구현하는 연구로 이루어졌다. 먼저, 간단한 DNA 구성 요소로 구현된 M-입력/N-출력 논리 게이트를 구성하였다. 타일 설계의 어려움으로 인해 M > 2 입력 논리 게이트의 실험적인 시연은 보고되지 않았고, 이를 위해 ‘연산자’ 타일을 도입하였다. DNA 타일에 적절한 결합 도메인을 설계하고, 3-입력/1 출력 로직의 256 개 규칙 중 8 개의 다른 규칙에 의해 생성된 DNA 알고리즘 격자의 성장을 보여준다. DNA 격자는 단순하고 선과 유사한 무작위 및 혼합 패턴을 보여주며, 오류와 정렬 요인을 얻기 위해 분석하였다. 복수의 논리 게이트로 구현되는 산술 계산은 논리 알고리즘이 잘 확립되어 있으며 실험 구현 가능성이 높아 많은 주목을 받았다. 이러한 계산을 구현하기 위해 작은 분자가 사용되었지만 규칙 설계의 복잡성과 직접 검증을 위한 실험과제 때문에 DNA 타일 기반 계산기는 거의 다루어 지지 않았다. 따라서 DNA 알고리즘 자가 조립을 통해 덧셈 및 뺄셈 연산을 수행하기 위해 DNA 기반 계산기를 구성하였으며 원자힘현미경(AFM)을 통해 결과를 보였다. DNA 나노 구조물의 헤어핀 구조를 이용하여 N (N = 1 또는 2)-입력/1-출력의 3 진법 알고리즘 DNA 구조물을 형성하는 DNA 규칙 타일이 구상하였다. 3 진수의 정보는 헤어핀이 없고 (0), 짧고(1), 긴(2) DNA 타일에 인코딩 된다. 1-입력/1-출력 게이트에 대한 6 가지 특정 규칙과 2-입력/1-출력 게이트에대한 선 모양의 패턴을 구현하여 융합, 선형, 교대 및 정류 패턴을 구성하였다. 패턴은 원자힘현미경을 통해 시각화 하였으며, 결정 성장 중 오차를 분석하였다. 해당 방법은 3 이상의 기본값을 갖는 시스템으로 확장될 수 있다. 자연에 존재하는 다양한 패턴 형성 메커니즘을 이해하기 위해 여러 모델과 시뮬레이션이 제안되고 수행되었다. 세포 자동화 모델을 이용하여 느티나무의 나무껍질 패턴과 유사한 DNA 격자에서 얻은 시뮬레이션 패턴과 실험 패턴을 구현하였다. 시뮬레이션 패턴과 실험 패턴은 3-입력/1-출력 알고리즘 논리게이트에서 6 가지의 대표적인 규칙을 통해 생성된다. DNA 알고리즘 자가조립을 통해 얻은 실험 패턴은 원자힘현미경으로 시각화 하였다. 각 패턴 사이의 유사성을 분석하기 위해 세 가지 모듈(A, B, C)을 도입하였으며, 각 모듈 내에 존재하는 배열의 표준편차를 이용하여 유사도를 분석하였다.

High-definition dynamic magnetic resonance imaging for vascular structures and function

Park, Joonsik Sungkyunkwan university 2021 국내박사

This work introduces high-definition dynamic contrast enhanced (DCE) MRI reconstruction methods for vascular structures and functions. To demonstrate the feasibility of high definition DCE MRI, a model based high definition DCE MRI for concurrent estimation of perfusion and permeability is developed. A time series of reference-subtracted signals is decomposed into one component that reflects main contrast dynamics and the other one that includes residual contrast agents (CA) and background signals. The former is described by linear superposition of a finite number of basic vectors trained from an augmented set of data that consists of tracer-kinetic model driven signal vectors and patient-specific measured ones. Contrast dynamics is estimated by solving a constrained optimization problem that incorporates the linearized signal decomposition into the measurement model of DCE MRI and then combining the main component with the background-suppressed, residual CA signals. This is the first work that prospectively enables rapid temporal sampling with 1.5 sec while simultaneously achieving high isotropic spatial resolution with 1.0 mm3, enhancing estimation of both patient-specific inputs and outputs for quantification of microvascular functions. Simulations and experiments are performed to demonstrate the effectiveness of the proposed method in patients with brain cancer. In addition, to simultaneously visualize the macroscale and microscale information, we proposed joint reconstruction of vascular structures and microvascular function maps directly from highly undersampled data using vascular heterogeneity priors. In DCE MRI, macrovascular such as arteries and veins are characterized by rapid, high uptake and wash-out of contrast agents (CA) compared with capillaries, while depending on CA uptake and wash-out signal patterns, capillary tissues can be categorized into highly perfused, moderately perfused, and necrotic regions. Given the above considerations, vascular structural priors are constructed to differentiate penalties on arteries relative to capillary tissues, while microvascular functional priors implicate that nonnegative contrast dynamics in capillary regions can be delineated by linear superposition of a finite number of basic vectors that reflect actual, tissue-specific signal patterns. Both vascular structure and microvascular function maps are jointly estimated by solving a constrained optimization problem in which the above vascular heterogeneity priors are represented by spatially weighted nonnegative matrix factorization. Retrospective and prospective experiments are performed to validate the effectiveness of the proposed method in generating well-defined vascular structure and microvascular function maps for patients with brain cancer at high reduction factors. 조영증강 자기공명영상(DCE MRI)은 혈관계의 구조적 정보과 기능적 정보를 시각화 하기 위해 많이 사용되는 영상 기법입니다. 혈관계의 구조적 정보와 미세혈관계의 기능적 정보를 얻기 위해서는 고해상도의 조영ㅊ증강영상을 필요로 합니다. 그러나 자기공명영상의 기술적인 한계로 인해, 높은 시공간해상도의 영상을 획득하기 어렵습니다. 위 연구에서는 먼저, 고해상도의 조영증강영상의 필요성을 제안하기 위해, 언더샘플링을 통해 획득한 고해상도의 자기공명영상 데이터를 새롭게 개발한 선형신호모델기반 영상복원 알고리즘과 결합하여, 고해상도의 데이터를 복원하고, 복원된 고해상도 조영증강 데이터 분석을 통한 미세혈관계의 혈류와 투과율 정보의 변화를 제시함으로서, 정확한 미세혈관계 기능적 정보를 위한 고해상도 조영증강영상의 중요성을 제안하고 있습니다. 더불어, 혈관계 정보를 획득하기 위해 다량의 조영제를 반복적으로 투입하는 하는 기존의 연구와는 달리, 본 연구에서는 단일 조영증강으로 고해상도 거시혈관계계 구조적 영상과 정확한 미세혈관계의 기능적 정보를 동시에 획득하는 연구를 제안하고 있습니다. 위의 연구에서 제시한 고해상도 조영증강영상의 중요성에 기반하여, 구조적 거시혈관계와 미세혈관계의 선형정보를 조영증강 신호 패턴에 기반하여 수학적으로 정의한 후, 거시혈관계와 미세혈관계를 구분하면서 동시에 미세혈관계에는 비지도 패턴분석에 기반한 수학적 보델을 적용함으로서, 단일 조영증강데이터로부터 구조적 거시혈관계와 미세혈관계의 기능적 정보를 직접적으로 추출하는 방법을 제안하고 있습니다. 결론적으로, 본 연구에서 제시한 기술을 통해, 고해상도의 조영증강 영상의 필요성을 제시하고, 단일 조영증강을 통한 통합적인 혈관계 정보를 추출하는 방법을 통해, 임상에서 넓게 적용되어, 뇌혈관장벽 누수에 기반한 다양한 질병예 적용 될 수 있을것입니다.