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Geographical Variations and Genetic Distances of Three Saxidomus purpuratus Populations ascertained by PCR Analysis

  • Yoon, Jong-Man
    • Development and Reproduction
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    • v.19 no.4
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    • pp.259-264
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    • 2015
  • Genomic DNA samples isolated from geographical purplish Washington clam (Saxidomus purpuratus) were obtained from three different regions in the Korean Peninsula: Geoje (Geoje population; GJP), Gunsan (Gunsan population; GSP) and a site of North Korea (North Korea population; NKP). The seven primers generated the total 369 loci that can be scored from the GSP clam population. 356 fragments were generated from the NKP clam population. The complexity of the banding patterns varies dramatically between the primers and three localities. In this study, 319 loci were identified in the purplish Washington clam from Geoje and 369 in the clam population from Gunsan: 221 specific loci (69.3%) in the GJP clam population and 300 (81.3%) in the GSP population. These results demonstrate that the primer detected a large quantity of specific fragments, suggesting that the genetic variation in the GSP is higher than in the GJP population. In particular, the BION-28 primer gave DNA profiles with more fragments than the other six primers in the NKP population. The oligonucleotides primer BION-75 produced 21 unique loci to each population, which were ascertaining each population, approximately 250 bp, 300 bp and 400 bp, in the GJP population. Outstandingly, the primer BION-50 detected 21 shared loci by the three populations, major and/or minor fragments of sizes 150 bp, which were matching in all samples. With regard to average bandsharing value (BS) results, individuals from GJP population (0.743) displayed higher bandsharing values than did individuals from GSP population (0.606). In the present study, the dendrogram gained by the seven oligonucleotides primers indicates three genetic clusters: cluster 1 (GEOJE 01 ~ GEOJE 07), cluster 2 (GUNSAN 08 ~ GUNSAN 14), cluster 3 (N.KOREA 15 ~ N.KOREA 21). Among the twenty one clams, the shortest genetic distance that revealed significant molecular differences was between individuals 08 and 09 from the NKP population (genetic distance = 0.073), while the longest genetic distance among the twenty-one individuals that demonstrated significant molecular differences was between individuals GEOJE no. 03 and GUNSAN no. 09 (genetic distance = 0.669). Comparatively, individuals of GJP population were properly closely related to that of NKP population, as revealed in the hierarchical dendrogram of genetic distances. In due course, PCR analysis has revealed the significant genetic distance among three purplish Washington clam populations. PCR fragments discovered in this study could be valuable as a DNA marker of the three geographical clam populations to distinguish.

Task and Curriculum Contents of Applied Ecological Engineering Education (응용생태공학 교육의 임무와 교과내용)

  • Kim, Jeong-Gyu;Lee, Woo-Kyun
    • Ecology and Resilient Infrastructure
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    • v.2 no.1
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    • pp.1-11
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    • 2015
  • The needs for ecological engineering, which can design ecosystems that integrate human society and their natural environment for the benefit of both, has increased. The Korean Society of Ecology and Infrastructure Engineering (KSEIE) was established for this purpose and has contributed to the research and development of theories and technologies in related fields. However, the current state of educational services and contents of ecological engineering is still needed to be standardized and systematized. In this paper, we outlined the trends of ecological engineering education at international and domestic levels and proposed a sample services and curriculum, brought from the discussions and suggestions made during the forum, Founding the Education for Ecological Engineering, held by the KSEIE. Education of ecological engineering can nurture people who can design and manage ecosystems for the benefits of human and natural society and can restore ecosystems disturbed artificially. The services and curriculum have to meet and cover the challenges facing the future of ecological engineering; a. the ethical interpretation of the balance between human and nature, b. developing and strengthening its relationship with other scientific disciplines and societies - business, policy, education, and practitioners, c. identify and fuse the key ecological engineering principles into other discipline. We proposed a three layers curriculum system, basic (mathematics, physics, chemistry, biology, etc.), core (ecology, hydrology, engineering, etc.), and advanced subjects. The first two can belong to an undergraduate program and the last two can be put into graduate program. The selection of subjects is according to the purpose and needs of the major.

Three-Dimensional Analysis of the Mesophyll Plastids Using Ultra High Voltage Electron Microscopy (초고압전자현미경에 의한 엽육세포 색소체 미세구조의 3차원적 분석)

  • Kim, In-Sun;Park, Sang-Chan;Han, Sung-Sik;Kim, Eun-Soo
    • Applied Microscopy
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    • v.36 no.3
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    • pp.217-226
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    • 2006
  • Image processing by ultra high voltage electron microscopy (UHVEM) and tomography has offered major contributions to research in the field of cellular ultrastructure. Furthermore, such advancements also have enabled the improved analysis of three-dimensional cellular structures in botany. In the present study. using UHVEM and tomography, we attempted to reconstruct the three-dimensional images of plastid inclusions that probably differentiate during photosynthesis. The foliar tissues were studied Primarily with the TEM and further examined with UHVEM. The spatial relationship between tubular elements and the thylakoidal membrane and/or starch grains within plastids mainly have been investigated in CAM-performing Sedum as well as in $C_4$ Salsola species. The inclusion bodies were found to occur only in early development in the former, while they were found only in mesophyll cells in the latter. The specimens were tilted every two degrees to obtain two-dimensional images with UHVEM and subsequently comparison has been made between the two types. Digital image processing was performed on the elements of the inclusion body using tilting, tomography, and IMOD program to generate and reconstruct three-dimensional images on the cellular level. In Sedum plastids, the inclusion bodies consisted of tubular elements exhibiting about 20 nm distance between elements. However, in Salsola, plastid inclusion bodies demonstrated quite different element structure, displaying pattern, and origin relative to those of the Sedum. The inclusion bodies had an integrative relationship with the starch grains in both species.

The Oogenesis of Tiger Barb, Cyprinidae, Teleostei (경골어류 잉어과 Tiger barb의 난자형성과정)

  • Jung, Han-Suk;Joo, Kyung-Bok;Kim, Dong-Heui
    • Applied Microscopy
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    • v.41 no.3
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    • pp.163-168
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    • 2011
  • Tiger barb (Puntius tetrazona Bleeker, 1855) is a teleost belonging to Cyprinidae. The oogenesis of tiger barb was investigated by light microscope. The ovary was of white and ellipsoidal shape with the major axis 2 cm and the minor axis 1 cm. Cytoplasm of oogonia was basophilic and many nucleoli were located at inside of nuclear membrane. In early stage of primary oocyte, yolk vesicles were distributed only in the marginal area. In secondary oocyte, the egg envelope was formed and yolk vesicles was formed in the cytoplasm. The basophilic substance of cytoplasm was changed to acidic. In case of matured egg, thickness of egg envelope and size of egg were increased. The yolk vesicles were changed to yolk mass in accordance with development. Also, there is not the formation of oil droplets in cytoplasm. In conclusion, the oogenesis of tiger barb was characterized by the increase in cell size, the formation of yolk, the decrease of basophilic substance in the cytoplasm, and formation of yolk mass.

The Oogenesis of Three Spot Gourami, Belontiidae, Teleostei (경골어류 등목어과 Three spot gourami의 난자형성과정)

  • Chang, Byung-Soo;Jung, Han-Suk;Joo, Kyung-Bok;Kim, Dong-Heui
    • Applied Microscopy
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    • v.41 no.3
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    • pp.155-161
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    • 2011
  • Three spot gourami (Trichogaster trichopterus Pallas, 1770) is a teleost belonging to Belontiidae. The oogenesis of three spot gourami was investigated by light microscope. The ovary was of light peach color and ellipsoidal shape with the major axis 2 cm and the minor axis 1 cm. Cytoplasm of oogonia was basophilic and many nucleoli were located at inside of nuclear membrane. In primary oocyte, lipid droplets were distributed only in the marginal area first, than at nuclear envelope near. In secondary oocyte, the egg envelope was formed and yolk vesicles was formed in the marginal area. The basophilic substance of cytoplasm was changed to acidic. In case of matured egg, thickness of egg envelope and size of egg were increased. The yolk vesicles were changed to yolk mass in accordance with development. The fertilized eggs were the colorless, transparent, spherical, adhesive and pelagic type. A large oil droplet was located in vitelline membrane of the fertilized egg. In conclusion, the oogenesis of three spot gourami was characterized by the increase in cell size, the formations of lipid droplets and yolk, the decrease of basophilic substance in the cytoplasm, and formation of one large oil droplets.

EGFR Analysis in Cytologic Samples of Lung Adenocarcinoma by Microdissection (미세 절제에 의한 폐 선암 세포 검체에서 EGFR 분석)

  • Han, Jeong Yeon;Lee, Hoon Taek;Oh, Seo Young
    • Korean Journal of Clinical Laboratory Science
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    • v.47 no.3
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    • pp.125-131
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    • 2015
  • The discovery of activating mutations in EGFR in a subset of lung adenocarcinomas was a major advance in our understanding of lung adenocarcinoma biology, and has led to groundbreaking studies that have demonstrated the efficacy of tyrosine kinase inhibitor therapy. Cytologic specimen procedures have become increasingly popular for obtaining diagnostic material in lung carcinomas. However, frequently the small amount of material or sparseness of tumor cells obtained from cytologic preparations limit the number of specialized studies, such as mutation analysis, that can be performed. In this study we used microdissection to isolate small numbers of tumor cells to assess for EGFR mutations from 76 cytological smear slides of patients with lung adenocarcinomas. We compared our results with previous molecular assays that had been performed on either surgical or cytology specimens as part of the patient's initial clinical work-up. Not only were we able to detect the identical EGFR mutation through the pyrosequencing, but we were also able to consistently detect the mutation from as few as 25 microdissected tumor cells. Furthermore, isolating a purer population of tumor cells resulted in increased sensitivity of mutation detection as we were able to detect mutations from microdissection-enriched cases. Therefore, microdissection can not only significantly increase the number of lung adenocarcinoma patients that can be screened for EGFR mutations, but can also facilitate the use of cytologic samples in the newly emerging field of molecular-based personalized therapies.

Relationship between fish assemblages community and Streamline complexity (어류군집 특성과 하안형태복잡도와의 관계)

  • Kim, Jin-Ah;Lee, Sang-Woo;Hwang, Gil-Son;Kim, Chulgoo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.2
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    • pp.19-29
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    • 2012
  • Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.

A Comparative Analysis of the Kinetic Structure in Lectures on a High School Science (고등학교 공통 과학 강의에서 교사에 따른 역동적 구조의 정량적 비교 분석)

  • Yu, Seung-Geun;Lee, Joon-Sang
    • Journal of The Korean Association For Science Education
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    • v.20 no.4
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    • pp.505-509
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    • 2000
  • The kinetic structure of the content of instructions at the unit of 'heart and circulation' in "the common science", which was respectively given by two teachers majored in biology and two teachers majored in earth science was investigated. Concerning of the mean of the fundamental coefficient (B1), the mean of weighted coefficients (B2) and the progression of instruction (P), T4 (B1, 0.14; B2, 0.82; P; 0.86) teacher showed relatively lower kinetic structure and faster progression than those of the others. The other teachers showed a different level of the kinetic structure and progression: T1(B1, 0.21; B2, 0.86; P; 0.79), T2 (B1, 0.02; B2, 0.85; P; 0.80), and T3 (B1, 0.22; B2, 0.83; P; 0.78). T1 teacher who showed the largest total frequency of verbal elements, the great number of sorts of verbal elements and secondary span, had a higher level of the kinetic structure, but T4 teacher showed the lowest level of total frequency of verbal elements, the great number of sorts of verbal elements and secondary span. The main reason why T4 teacher's instruction achieved a lower level of kinetic structure was estimated that he neglected to reorganize teaching materials and he showed a small number of discourse units. In addition, the unit of 'heart and circulation' was less related to T4 teacher's major and T4 teacher had a shorter teaching experience than those of the others. T4 teacher also took charge of only one class, and this did not allow to instruct repeatedly.

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A Study on Actual Conditions and Patterns of Sexual Harassment in the Korean Adolescents (한국 청소년의 성희롱실태 및 유형에 관한 조사연구)

  • Kim, Young-Hae;Lee, Hwa-Za;Jung, Eun-Soon;Kim, Lee-Soon;Moon, Sun-Hwa;Jung, In-Kyung
    • The Journal of Korean Academic Society of Nursing Education
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    • v.7 no.2
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    • pp.196-206
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    • 2001
  • The purpose of this study was to identify Korean adolescents' sexual harassment conditions and patterns in schools as well as their psychological reactions when they are under sexual harassments or they committed sexual harassments. The subjects were 475 middle and high schoolers in Pusan and Gyeong Sang Nam-Do. The survey was executed from July 1 through Dec. 31, 2000. The collected data was analyzed by SPSS WIN 8.0 using percentage, mean. The results of this study were as follows: 1. the linguistic sexual harassment such as 'lewd jokes or dirty talks' was the major pattern(35.4%), The body touching such as 'kiss or embracing', 'internet transmission of pornography', 'sexual harassing of body characteristics', touching breast', 'grasping of hands or body touching', 'body touching in secret place', 'urging to sit in touch or on knees', 'exposing of special body areas', and 'showing pornography' followed in a row. 2. The eighteen point three percents of subjects had the experience to commit sexual harassment. The forty four point seven percent of above subjects committed it against their classmates. The first time to commit sexual harassment was their middle school period (38.4%). Their motives to commit it were as under: 'killing time'(48.8%), 'annoying', 'attracting attention from the other sex', 'expressing lovely emotions', 'urging of their friends', 'misunderstanding that the other partners felt good when they experienced sexual harassment, 'showing their strength' etc. their with committing harassments they felt as under ; 'joyful'(61.6%), 'funny,' 'desirous to try again', 'thrilling', 'breaking stress', very pleasant', 'exciting', 'regretful', 'guilty', and 'feeling fear' etc. 3. Twenty four point two percents of the population exposed to sexual harassments. The sexual harassers were almost their classmates (42.7%). And then unknown people', 'boy or girl friends and school staffs' followed in a row. The places where harassments happened were 'inside classroom'(69.8%), 'school bus and subway', 'outside school', etc. The feelings when experienced harassments were 'anger' (51.3%), 'hurting self-respect', 'embarrassing', 'rejection', 'insulting', 'shame', 'fear', 'dislike', 'anxiety', 'melancholy' etc. The reasons not to have consultations after sexual harassments were 'worrying to be well-known'(49.6%), 'believing not helpful enough', 'regarding simple mischief', 'trying to revenge directly', 'understanding their mistakes', 'worrying retaliation' etc.

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Expression of Luteinizing Hormone (LH) Subunit Genes in the Rat Ovary (흰쥐 난소에서의 Luteinizing Hormone (LH) Subunit 유전자 발현)

  • Lee, Sung-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.25 no.2
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    • pp.199-205
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    • 1998
  • The present study was performed to analyze the expression of LH genes in the rat ovary. Expression of LH subunit genes in the rat ovary was demonstrated by amplification of ovarian RNA by RT-PCR. The ovarian $LH_\beta$ transcripts contained at least two parts of the published cDNA structure, the pituitary exons 1, 2 and 3 and the part of testicular ex on 1 in the major trancripts form in rat testis. Using RIA, significant amount of LH-like molecules were detected in crude ovarian extracts, and the competition curves with increasing amount of tissue extracts were parallel with those of standard peptide, indicating that the ovarian immunoreactive LH-like material is similar to authentic pituitary LH molecule. The administration of PMSG to immature rats resulted in a sharp decrease of the ovarian LH contents after 24 h post-injection. In conclusion, these findings demonstrate that genes for LH subunits are expressed in the rat ovary, and suggest that LH can playa central role in regulation of female reproduction with both endocrine (by pituitary LH) and auto- and/or para-crine (by ovarian LH) manner.

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