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A study on development of plastic vial tube for the DNA detection process (DNA 검출 공정 전용 플라스틱 튜브형 시험관 개발에 관한 연구)

  • Choi, Kyu-wan;La, Moon-woo;Gang, Jung-hee;Chang, Sung-ho
    • Design & Manufacturing
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    • v.11 no.3
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    • pp.35-40
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    • 2017
  • PCR(Polymerase chain reaction) is a technique to replicate and amplify a desired part of DNA. It is used in various aspects such as DNA fingerprint analysis and rare DNA amplification of an extinct animal. Especially in the medical diagnosis field, it provides various measurement methods at the molecular level such as genetic diagnosis, and is a basic tool for molecular diagnostics. The internal shape of the plastic vial tube for PCR analysis used in the DNA detection process, and the surface roughness and internal cleanliness can affect detection and discrimination results. The plastic vial tube demanded by the developer of the PCR analysis equipment should be changed to a structure that eliminates the residual washing solution in the washing process to ensure the internal cleanliness. Thus the internal structure and the internal surface design for improving the PCR amplification efficiency are key issues to develop the plastic vial tube for the DNA detection process.

The Color Enhancement of Brown Tinted Diamonds with Annealing Temperatures in 5.6 Gpa-10 min HPHT (천연 갈색다이아몬드의 5.6 Gpa-10분 조건에서 처리온도에 따른 색 변화 연구)

  • Li, Feng;Song, Oh-Sung
    • Korean Journal of Metals and Materials
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    • v.50 no.1
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    • pp.23-27
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    • 2012
  • The color of a natural diamond that contains nitrogen impurities can be enhanced by a high pressure high temperature (HPHT) treatment. Type IaAB diamond samples containing nitrogen impurities were executed by HPHT process of 5.6 Gpa, 10 min by varying the annealing temperature at 1600, 1650, and $1700^{\circ}C$. Property characterization was carried out using an optical microscope, FT-IR spectrometer, low-temperature PL spectrometer, and micro Raman spectrometer. By observing optical micrographs, it can be seen that diamond sample began to alter its color to vivid yellow at $1700^{\circ}C$. In the FT-IR spectrum, there were no Type changes of the diamond samples. However, amber centers leading to brown colors lessened after $1700^{\circ}C$ annealing. In the PL spectrum, all the H4 centers became extinct, while there were no changes of yellow color center H3 before or after treatment. In the Raman spectrum, no graphite spots were detected. Consequently, diamond color enhancement can be done by higher than $1700^{\circ}C$ HPHT annealing at 5.6 GPa-10 min.

Genetic Variation and Conservation of the Endangered Species Cotoneaster wilsonii (Rosaceae) from Ulleung Island

  • Park, Jiwon;Lee, Junsoo;So, Soonku;Kim, Muyeol
    • Korean Journal of Plant Taxonomy
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    • v.39 no.3
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    • pp.125-129
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    • 2009
  • The genetic diversity plays a significant role in determining a species' survival and perseverance. Endangered species often lack genetic variation, which makes them vulnerable to numerous dangers of extinction including selection, genetic drifts and human interference. Knowing an endangered species' genetic background greatly enhances conservation efforts since it reveals why, what and how to conserve that species. Cotoneaster wilsonii is an endangered plant species endemic to Ulleung island, but not enough genetic research has been done on this taxon for its effective conservation plans. In this study, three populations of C. wilsonii in Ulleung island underwent allozyme analysis through starch gel electrophoresis. 10 loci were analyzed and F-statistics was calculated. Overall data indicated that C. wilsonii possessed low genetic diversity with intense inbreeding, heterozygote deficiency and low differentiation among populations. These results implied that C. wilsonii was recently introduced to the Ulleung island from ancestor species, and did not have much time to differentiate. Current status of C. wilsonii habitats is very fragile and vulnerable, with increasing tourism constantly threatening the species' survival. It is very likely that C. wilsonii will become extinct in near future unless organized conservation protects its populations and genetic diversity.

RE-ACCELERATION OF FOSSIL ELECTRONS BY SHOCKS ENCOUNTERING HOT BUBBLES IN THE OUTSKIRTS OF GALAXY CLUSTERS

  • Kang, Hyesung
    • Journal of The Korean Astronomical Society
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    • v.51 no.6
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    • pp.185-195
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    • 2018
  • Galaxy clusters are known to host many active galaxies (AGNs) with radio jets, which could expand to form radio bubbles with relativistic electrons in the intracluster medium (ICM). It has been suggested that fossil relativistic electrons contained in remnant bubbles from extinct radio galaxies can be re-accelerated to radio-emitting energies by merger-driven shocks via diffusive shock acceleration (DSA), leading to the birth of radio relics detected in clusters. In this study we assume that such bubble consist primarily of thermal gas entrained from the surrounding medium and dynamically-insignificant amounts of relativistic electrons. We also consider several realistic models for magnetic fields in the cluster outskirts, including the ICM field that scales with the gas density as $B_{ICM}{\infty}n^{0.5}_{ICM}$. Then we perform time-dependent DSA simulations of a spherical shock that runs into a lower-density but higher-temperature bubble with the ratio $n_b/n_{ICM}{\approx}T_{ICM}/T_b{\approx}0.5$. We find that inside the bubble the shock speed increases by about 20 %, but the Mach number decreases by about 15% in the case under consideration. In this re-acceleration model, the observed properties of a radio relic such as radio flux, spectral index, and integrated spectrum would be governed mainly by the presence of seed relativistic electrons and the magnetic field profile as well as shock dynamics. Thus it is crucial to understand how fossil electrons are deposited by AGNs in the ICM and how the downstream magnetic field evolves behind the shock in detailed modeling of radio relics.

Non-linear dynamics of wetland vegetation induced by groundwater table (지하수위와 연계된 습지 식생의 비선형 동역학)

  • Lee, Okjeong;Kim, Sangdan
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.132-139
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    • 2019
  • Bi-directional interaction between vegetation and groundwater table has a great influence on the dynamics of wetland vegetation. In this study, nonlinear dynamics of wetland vegetation affected by groundwater are analyzed. The effect on groundwater is described as a loss term in the governing equation of wetland vegetation and it is explored how the wetland vegetation is likely to converge into two attractors by groundwater table change. From this conceptual approach, the vulnerability to catastrophic shifts in stable state where the current vegetation species are extinct and stabilized by other vegetation species is analyzed in response to groundwater table.

Distribution Characteristics and Diversity of Alpine and Subalpine Plants Growing Naturally in National Parks (국립공원 내 자생하는 고산 및 아고산식물의 분포 특성과 다양성)

  • Hyun-Hee Kim;Hyeong-Jin Yoon;Jin-Won Kim
    • Journal of Environmental Science International
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    • v.33 no.6
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    • pp.367-382
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    • 2024
  • Alpine and subalpine plants are isolated and distributed in mountaintop areas at high altitudes and, are among the species most vulnerable to global warming. If the rate of warming continues at its current rate, it is highly likely that this species will be unable to find new refugia and will be the last to go extinct in their current habitats. Therefore, research on the distribution and diversity of alpine and subalpine plants is urgently needed and is important from the perspective of biodiversity conservation. Therefore, this study focused on the distribution of alpine and subalpine plants native to national parks. Alpine and subalpine plants distributed across the 12 national parks accounted for approximately half (47.78%) of all alpine plants in Korea. The average relative frequency of occurrence was 0.23, plant similarity between national parks was 37.19%, and beta diversity was 0.63. The number of species was positively correlated with the latitude, elevation, and area of the national park. Thus the geographical distributions of alpine and subalpine plants haves distinct spatial specificities and physical environmental differences.

Latency in the Architectural Space of Mies van der Rohe (미스 반 데어 로에 건축공간의 잠복성)

  • Chung, Mann-Young;Choe, Eun-Guk
    • Journal of architectural history
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    • v.15 no.3
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    • pp.119-135
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    • 2006
  • This study based on the hypothesis which the spatial qualities in the Mies's early works are not extinct but potentially immanent in his latter works. In Mies's early works, destruction of outline, centrifugal extension of fluid space, and asymmetry are distinctly showed. These qualities probably revert to the indefiniteness of space. In Mies's latter works, however, these dynamic qualities are disappeared. Geometrically precise outline and exact grid structure represent universal space derived from zero-degree pure box. These qualities probably revert to tile definiteness of space, characterized by the unmovable emptiness. Although Mies works vary in external form, his expression technique of space reveals continually both the qualify of definitive and indefinitive space. For example, in the Museum for a Small City(1942) unbuilt project. elements defined by the perspective are fixed and static, but elements defined by the collages are floated and dynamic. The former reigns over the realized buildings of Mies, while the latter seems to be latent in terms of Schein which transcends reality. If we can penetrate this point, it's possible to read the other side of Mies' architectural works, distinct from both the canonized interpretation and the excessive criticism. Point is that later works of Mies must be understood as interplay of universal space appeared as phenomenon and flowing elements latent in. Architectural space of Mies keeps a distance with actual space through latent manner of being while preserves the empirical actuality It provides us with an occasion which appears only in an instant, in which even the ordinary things reveal its poetics.

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Systematic Studies of Korean Rodents. V. Morphometric and Chromosomal Analyses on Island Populations of Striped Field Mice (Apodemus agrarius coreae) in Southwestern coasts of the Korean Peninsula (한국산 설치류의 계통분류학적 연구 5.한반도 남서해안의 섬들에 살고 있는 등줄쥐들의 형태적 형질 및 염색체의 분석)

  • Koh, Hung Sun
    • Animal Systematics, Evolution and Diversity
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    • v.5 no.1
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    • pp.1-12
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    • 1989
  • Samples of striped field mice, Apodemus agrarius Pallas, from eight localities in s southwestern islands and coasts in Korea were collected and analyzed together with samples from the mainland and Jeju island. In chromosomal analyses no variation was revealed in karyotypes among samples from Korea. In morphometric analyses samples from Wan and Bogil islands formed a large-size g group (A. agrarius chejuensis) with those from Jeju island, whereas samples from Jin and H Hajo islands formed a small-size group (A. agrarius coreae) with those from the mainland including southwestern coasts It is supposed that small-size population of striped field mice in Wan and Bogil islands w were extinct and replaced by large-szie population of striped field mice immigrated from Jeju island by humans.

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The Optimization of Offset Printing Process for High Quality Color Reproduction(II);Platemaking and Presswork (고품질 색재현을 위한 오프셋인쇄 공정의 최적화에 관한 연구(II);제판과 인쇄공정을 중심으로)

  • Kim, Sung-Su;Kang, Sang-Hoon
    • Proceedings of the Korean Printing Society Conference
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    • 2007.11a
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    • pp.13-28
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    • 2007
  • Producing printing plate is essential progress to do offset printing. In this Film-less period, the more PS plate becomes extinct, the more the age of the Plate-Making of Exposure declines the place to stand. To do offset printing, the CTP (Computer to Plate) is taking a place of PS plate that covers speed, quality and economical problems. The biggest advantage of using CTP is that laser directly goes to the plate, thus there are no dust from the Plate-Making of Exposure. It is also theoretically able to print 200lpi${\sim}$300lpi as well as print 1751pi, because it has over 2400dpi resolution. The high quality printing could be available inside of the country, if printing machine keeps the optimum condition in offset printing. The CTP has many advantages, however there is a difficulty for the operators to preserve the equipment. The actual circumstance is that they cannot make a decision about how many dots need to be generated, and also it is necessary to know how to establish the setup at RIP on CTP to make the optimum condition output. If offset printing machine keeps the optimum condition, it would be able to print up to high quality printing however it is hard to comment what is the optimum condition for the printing machine. Anyone could say easy subjectively that machine is in the optimum condition, however it is objectively hard to estimate by number. In this research GATF / Plate Test target used to analyze the image and to make numerical value of the optimum condition of the CTP. It also used GATF / The sheep fed test printing 5.0 to know the density of the color representation, dot gain and gray balance for the optimum condition of the print machine. The purpose of this research is to represent the ISO 12647-2 which is the international standard with domestic printing equipments.

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Design of U-IT Technology transfer Re-Auction System Model (U-IT 기술이전 역경매 시스템 모델의 설계 개발)

  • Kim, Hye-Sun;Jeon, In-Oh;Yang, Hae-Sool
    • The Journal of the Korea Contents Association
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    • v.9 no.8
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    • pp.99-112
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    • 2009
  • The research is to develop U-IT Technology Transfer Re-auction System Model for technology transfer enable transactions of buyer-oriented. The buyer sends condition technology parts and data informations to provider. The First step, The buyer sends condition technology parts and data informations to provider. The Second step, the buyer's technology and conditions in the First step will be transferred to the DB of a provider who can provide that technology. The Third step, a provider can bid after inputting the conditions. The Fourth step, the buyer decides the ranking of successful bids in condition-optimized auction process. The Fifth step, the buyer invites a provider to be a successful bidder. The last step, if there's no successful bid within the period, the sale considered failed. The buyer-oriented re-auction system is that the deal will become extinct automatically when its sale failed more than two times.