• Journal of Korean Neurosurgical Society
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• 제64권3호
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• pp.329-339
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• 2021

It has been recognised for over a century that the events of gastrulation are fundamental in determining, not only the development of the neuraxis but the organisation of the entire primitive embryo. Until recently our understanding of gastrulation was based on detailed histological analysis in animal models and relatively rare human tissue preparations from aborted fetuses. Such studies resulted in a model of gastrulation that neurosurgeons have subsequently used as a means of trying to explain some of the congenital anomalies of caudal spinal cord and vertebral development that present in paediatric neurosurgical practice. Recent advances in developmental biology, in particular cellular biology and molecular genetics have offered new insights into very early development. Understanding the processes that underlie cellular interactions, gene expression and activation/inhibition of signalling pathways has changed the way embryologists view gastrulation and this has led to a shift in emphasis from the 'descriptive and morphological' to the 'mechanistic and functional'. Unfortunately, thus far it has proved difficult to translate this improved knowledge of normal development, typically derived from non-human models, into an understanding of the mechanisms underlying human malformations such as the spinal dysraphisms and anomalies of caudal development. A paediatric neurosurgeons perspective of current concepts in gastrulation is presented along with a critical review of the current hypotheses of human malformations that have been attributed to disorders of this stage of embryogenesis.

• 패션비즈니스
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• 제23권2호
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• pp.48-61
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• 2019

The objective of this study was to derive a list of creative thinking techniques applied with the requirements of the appropriate technique for the task of fashion design development among the process of fashion product planning. This was done through the analysis of thinking techniques by the type of thinking and idea method. Also, the study presented how each creative thinking technique derived is applied to the task of developing fashion design. The scope of the study was 'Fashion Design Development Task', which corresponds to the design sketch of a fashion item based on the seasonal design concept derived through the fashion design planning stage. Research on the thinking techniques consisted largely of the process of idea thinking, the elements of creative thinking, the patterns and types of thinking. Four studies by Makoto, Michalko, De Bono, and Cox suggesting that the patterns and types of thinking techniques were analyzed for the purpose of this study as empirical studies through FGI of a group of five fashion experts. The analysis results showed that the thinking techniques suitable for the development of fashion design were derived from the technique of fractionation, attributive listing, scamper, morphological analysis, mind mapping, lotus blossom, pattern language, provocative operation, and forced connection. In particular, it can be confirmed that the scamper was treated as an efficient and practical technique in the many studies.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.98-104
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• 1999

The characteristics of the populations of shortnecked clam (Ruditapes philipinarum) originated from three different seed-production sites, Hadong, Kochang and Ulsan along the coast of Korea, were analysed by the morphological differences and the random amplified polymorphic DNA (RAPD) profiles. The morphology of the shell and survival rate for each population were also investigated 13-months after transplantation to a farming site in Shinsung. The morphology of the populations from Hadong and Kochang showed significant differences (P<0.05), but one year after transplantation to Shinsung, the morphology of these three populations was no longer significantly different (P>0.05). The template DNA for RAPD was efficiently extracted from the digestive diverticula of the clams. Up to 13 of amplified fragments were detected using arbitrary primers. Within the species of R. philipinarum, the genetic similarities ranged from 0.196 to 0.259. The populations from Hadong and Ulsan showed the highest similarity. The survival rates of the populations from Hadong $(69.4\%)$ and Ulsan $(63.8\%)$ were higher than that from Kochang $(41.7\%)$ 13-months after transplantation. From the RAPD analysis, it could be used as one of the primary criterion in determining which shellfish populations among various seed-production sites tend to be genetically similar and more adaptable and transplantable to a farming site.

• Applied Microscopy
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• 제24권1호
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• pp.11-27
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• 1994

The morphological development of the carotid body was studied by electron microscope in human fetuses from 40mm to 260mm crown rump length (10-30 weeks of gestational age). At 40mm fetus, the carotid body was composed of cluster of primitive glomus cells, primitive supporting cells, unmyelinated nerve fibers, and blood capillaries. In connective tissue between internal and external carotid arteries adjacent to the superior cervical sympathetic ganglion, two types of glomus cells through all prenatal period were found. Dark cells contained a dense cytoplasm with conspicuous large dense-cored granules, whereas light cells had a less dense cytoplasm with dense-cored granules. The light cells contained dense-cored granules that were smaller and less abundant than those in the dark cells. The primitive supporting cells appeared star-shaped with attenuated cytoplasmic extensions intervening between the adjacent glomus cells. Synaptic contact between the axon terminals and soma of the glomus cells were first observed at 40mm fetus. In 80-100mm fetus, the carotid body contained tightly packed collection of glomus cells and supporting cells which surrounded the abundant thin-walled blood vessels. Intercellular junctions between the glomus cells and adjacent cells were commonly seen. Nerve endings on the glomus cells have the form of small boutons and the other from of large calyces. During the second half of the fetal period, the glomus cells were completely enveloped by supporting cells and nerve terminals. At 260mm, the morphological features of carotid body were similar to those of human adult. The result of this study demonstrates that there are differences between the carotid body and aorticopulmonary bodies, especially with respect to their synaptic complexes, abundant blood capillaries, and two glomus cell types.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.610-616
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• 2002

The growth-inhibiting effects of Pinus densiflpora leaf-derived materials on nine human intestinal bacteria were investigated using the impregnated paper disk method, and their activities were compared with those of 13 commercially available terpenes. The biologically active constituent of the extract of P densiflora leaf was characterized as the monoterpene (1R)-(+)-$\alpha$-pinene by various spectroscopic analyses. Responses varied according to bacterial strain, chemicals, and dose. At 10 mg/disk, limonene and (1R)-(+)-$\alpha$-pinene strongly inhibited the growth of Clostridium perfringens, Staphylococcus aureus, and Escherichia coli, without adverse effects on the growth of five lactic acid-bacteria (Bifidobacterium adolescentis, B. bifidum, B. longum, Lactobacillus acidophilus, and L. casei). Little or no inhibition against seven bacteria was observed with anethole, borneol, camphor, caryophyllene, 1,8-cineole, estragole, linalool, and $\alpha$-terpineol. Structure-activity relationship revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S-(-)-$\alpha$-, and (1S-(-)-$\beta$-pinenes. Furthermore, the growth-inhibition against L. casei was much more pronounced in (1R)-(+)-$\beta$- and (In-(-)-$\beta$-pinenes than (1R)-(+)-$\alpha$- and (1S)-(-)-$\alpha$-pinenes. These results indicate that the (+)-$\alpha$ form seems to be required against C. perfringens and $\beta$ form against L. casei for growth-inhibiting activity. Morphologically, most strains of C. perfringens were damaged and disappeared at 5 and 2 mg/disk of (1R)-(+)-$\alpha$-pinene. Morphological study revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S)-(-)-$\alpha$-, and (1S)-(-)-$\beta$-pinenes. As naturally occurring growth-inhibiting agents, the Pinus leaf-derived materials described above could be useful preventive agents against diseases caused by harmful intestinal bacteria such as clostridia.

• 대한수의학회지
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• 제37권4호
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• pp.707-718
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• 1997

The present study was designed to investigate the morphological developments of the stomach in the prenatal and postnatal rats. The gastric fundus of 16- to 22-day-old fetuses, neonates, 7-day-old, 14-day-old, 21-day-old, and adult rats were observed by transmission electron microscopy. 1. In the 19-day-old fetuses, the gastric pits and the parietal cells were the primitive state, but the parietal cells contained numerous microvilli and mitochondria. 2. In the 20-day-old fetuses, the intracellular canaliculus appeared in the parietal cells, and glycogen granules were localized mainly in the basal part of the epithelial cells and parietal cells. 3. In the 20-day-old fetuses, the mucous granules and zonular occludens appeared in the gastric glandular cells adjacent to the parietal cells. 4. In the 21-day-old fetuses, the chief cells were identified in the lamina propria and these cells contained granular endoplasmic reticulum and zymogen granules. 5. In the 20- to 22-day-old fetuses, the definitive parietal cells were firstly appeared in pairs or groups within the lamina propria. These cells tended to be placed near the basement membrane and blood capillary, and frequently tended to be extruded into lumen of gland. 6. The endocrine cells were appeared at the basal areas of the gastric gland after the 14-day-old.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.205-208
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• 2006

북방한계선 주변의 한강하구는 지난 60년 동안 개발 및 이용이 금지되었기 때문에, 자연하천의 모습을 간직하고 있다. 그러나 최근 들어 경인수로를 비롯한 민간 이용을 위한 논의가 이루어지고 있으나, 한강하구의 기본적인 특성에 관한 정보가 부족한 실정이다. 본 연구에서는, 인공위성 합성개구레이더 (SAR)를 이용한 하구역 퇴적상의 변동 조사를 실시하고, 퇴적상을 기반으로 한강하구 뱃길을 제안하고자 한다. 2000년부터 2005년까지의 Radarsat-1 영상을 이용하여 시계열해석한 결과에 따르면, 1) 한강 하구역은 집중호우등에 의해 부유사가 많이 발생하며, 2) 식생역 (vegetated area) 은 거의 안정화단계에 있으며, 3) 퇴적상(bar)의 월 변동성은 크지 않으나, 매년 발생하는 호우 등에 의해 퇴적상의 위치 변화는 상당히 컸다. 여기서 얻어진 퇴적상의 변동 특성을 기반으로, 북방한계선 이남의 한강 수역에 대한 뱃길의 설계 방향을 제시하였다. 향후, 장기간에 대한 위성 및 현장 조가를 바탕으로 자연하천의 특성을 훼손하지 않는 범위에서의 개발이 이루어져야한다.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.26-32
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• 2000

Monospecific red tide by a toxic dinoflagellate belonging to the genus Alexandrium occurred at Chindong Bay in the southern coast of Korea and continued from April 6th to 15th in 1997. The ratio of its cell number to total phytoplankton cell number was much higher than $95\%$. This organism was identified as Alexandrium tamarense, although slight morphological differences were found comparing to the original and successive descriptions of the species. We found neither anterior nor posterior attachment pores in these cells of the bloom population. The occurrence of red tide caused by A. tamarense was first reported in Korea. Its plate formula is Po, Pc, 4', 6"c, 8s, 5"' and 2"". Thecal plates are thin with pore-like ornamentation. In those plates, the anterior part of the first apical plate (1') is narrower and its posterior end has sometimes a block-like accessory, but this variation was considered within the range of the morphological variability of this taxon. The cell density during the red tide exhibited a wide range of variation by the depth of water column, ranging from $2\times10^6$ cells$l^{-1}$ to $5\times10^6$ cells·$l^{-1}$. Water temperature varied from 11.8 to $12.3^{\circ}C$. Toxicity of A. tamarense during red tide was measured as $8.8\times10^5$. $MU\;\cdot\;cell^{-1}$ by mouse bioassay.

• 한국어류학회지
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• 제29권4호
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• pp.244-251
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• 2017

본 연구는 2016년에 한국 남해에서 채집된 둥글넙치과 자어를 분자방법으로 동정하였으며, 자어의 크기별 외부 형태를 상세히 기술하였다. 채집된 자어 15개체 (3.53~19.49 mm 체장)의 mitochondrial DNA (mtDNA) cytochrome c oxidase subunit I gene (COI) 434 bp의 염기서열을 비교한 결과, 모두 사량넙치로 확인되었다. 사량넙치의 자어는 2개의 길게 연장된 등지느러미 기조를 가지며, 등지느러미와 뒷지느러미 기저에 흑색소포가 일렬로 나 있는 반면 체측에는 흑색소포가 없었다. 성장하면서 체장에 대한 두장 및 두고의 비율이 증가 추세에서 감소 추세로 바뀌는 변곡점이 체장 9.93 mm~10.73mm에서 확인되었다. 사량넙치 자어는 형태적으로 가장 유사한 동백가자미(Psettina iijimae)와 달리 등지느러미와 뒷지느러미의 기저 근처에 흑색소포군을 가지지 않는 점에서 잘 구분된다.

• 한국수산과학회지
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• 제53권1호
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• pp.74-82
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• 2020

Dragonet fish (Callionymidae), living in benthic upper 900 m of all subtropical, tropical and temperate oceans, comprises 200 species in 20 genera worldwide, of which 18 species in 6 genera occur in Korea. Although dragonet fish plays an important role in linking between top predators and lower trophic levels, there are only few studies about their early life history. Herein, we present molecular and morphological data on larvae and juveniles of Bathycallionymus kaianus (Günther, 1880) collected from the Korean waters. During 2016 to 2018, one preflexion larvae [2.69 in total length (TL)], three flexion larvae (3.65 and 4.77 mm TL), six postflexion larvae (6.07 and 7.94 mm TL), and three juveniles (10.81 and 12.26 mm TL) were collected in the East Sea, Korea Strait, and Jeju Island using Bongo net. Of them, 13 individuals were identified through molecular markers (COI or 16S rRNA) and morphologically described. The larvae of B. kaianus are well distinguished from other species of Callionymidae in melanophore distribution, body shape and development of preopercular spine. It was very similar to larvae of two Repomucenus species, R. valenciennei and R. virgis, but was clearly distinguished in melanophore distribution, preopercular spine development, and head shape.