• Development and Reproduction
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• v.25 no.1
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• pp.1-14
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• 2021

The Syrian (golden) hamsters are seasonal breeders whose reproductive functions are active in summer and inactive in winter. In experimental facility mimicking winter climate, short photoperiod (SP) induces gonadal regression. The blood-testis barrier (BTB) of the sexually involuted animals have been reported to be permeable, allowing developing germ cells to be engulfed or sloughed off the epithelium of the seminiferous tubules. The expressions of genes related to the tight junction composing of BTB were investigated in the reproductive active and inactive testes. Claudin-11, occludin, and junctional adhesion molecule (JAM) were definitely expressed in the active testes but not discernably detected in the inactive testes. And spermatozoa (sperm) were observed in the whole lengths of epididymides in the active testes. They were witnessed in only cauda region of the epididymides but not in caput and corpus regions in animals with the inactive testes. The results imply that the disorganization of BTB is associated with the testicular regression. The developing germ cells are swallowed into the Sertoli cells or travel into the lumen, as supported by the presence of the sperm delayed in the last region of the epididymis. These outcomes suggest that both apoptosis and desquamation are the processes that eliminate the germ cells during the regressing stage in the Syrian hamsters.

• World Technopolis Review
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• v.4 no.2
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• pp.87-103
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• 2015

This paper aims to explore how firms develop and grow in regional clusters based in a developing country. The argument is that start-ups / small and large firms are able to grow by developing linkages or networks for resources within clusters - and this tenet is based on studies of firms that are based from such clusters as Silicon Valley in the US, Cambridge in UK and other clusters from which have evolved over long periods of time. Most of the time we hear narratives from the developed world where there are brownfield cluster development efforts. In developing countries governments are making efforts to develop clusters from scratch - which in this paper we term as greenfield cluster versus a brownfield development, which is where the cluster is developed based on existing and new organisations in a region. In this paper, we believe the context of clusters can be important in determining the way firms develop linkages for their growth - and we look at two contexts in Malaysia ie. A greenfield cluster and a brownfield cluster. The paper presents findings from case studies of firms in a greenfield cluster (Cyberjaya) and a brown field cluster (Penang) in Malaysia. The cases reveal fairly different approaches to development of linkages or networks, which we hope will provides insights to cluster development officials and policy makers and implications to researchers for developing studies of clusters and innovation systems.

• Fashion & Textile Research Journal
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• v.11 no.6
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• pp.961-967
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• 2009

In order to examine the availability of heat treatment for color developing in persimmon dyeing, the rayon fabrics dyed with persimmon extract from unripe persimmon which was used after stock and fermentation. Dyed fabrics were heated at various temperature and time by contacting press heat and drying heat. Color developing results were influenced by the difference of heating method. Press heating method is more available than drying heat method. Effect of temperature and time on ${\Delta}Ea^*b^*$ and color values of dyed rayon fabrics was considerable. Considering the practical aspect, The temperature around $140{\sim}160^{\circ}C$ and the time no longer 40 minutes can be reach the region of the full color developing by press heating process. It was very shortened than any other method(drying air heat, xenon radiation, sunlight). The dyed rayon fabrics with heat treatment have darker and deeper red-yellow color than which by sunlight and xenon radiation.

• Molecules and Cells
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• v.27 no.4
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• pp.397-401
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• 2009

Olig2 transcription factor is widely expressed throughout the central nervous system; therefore, it is considered to have multiple functions in the developing, mature and injured brain. In this mini-review, we focus on Olig2 in the forebrain (telencephalon and diencephalon) and discuss the functional significance of Olig2 and the differentiation properties of Olig2-expressing progenitors in the development and injured states. Short- and long-term lineage analysis in the developing forebrain elucidated that not all late Olig2+ cells are direct cohorts of early cells and that Olig2 lineage cells differentiate into neurons or glial cells in a region- and stage-dependent manner. Olig2-deficient mice revealed large elimination of oligodendrocyte precursor cells and a decreased number of astrocyte progenitors in the dorsal cortex, whereas no reduction in the number of GABAergic neurons. In addition to Olig2 function in the developing cortex, Olig2 is also reported to be important for glial scar formation after injury. Thus, Olig2 can be essential for glial differentiation during development and after injury.

• Journal of Environmental Impact Assessment
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• v.23 no.6
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• pp.505-516
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• 2014

Northeast Asia including China, Japan, Mongolia, Russia, DPRK and ROK, is a geographically close region that falls under the same environmental influence. Recently the region is not only facing serious domestic environmental problems with rapid economic growth, but also confronted with transboundary environmental problems and associated conflicts between countries. Unfortunately, Northeast Asia lacks a solid environmental management system among countries to deal with transboundary and other environmental issues. Transboundary Environmental Impact Assessment (TEIA) can, therefore, be one of the essential systematic measures in which environmental problems between countries would be negotiated. However, it would be necessary to have an indepth discussion of what we have to do first for implementing TEIA system in the region, and how to operate it while customizing each Northeast Asian country with different EIA system and socioeconomic circumstance. All these cannot be decided in a short time, and we need to invest enough time for discussing and considering them from various aspects. Recently, the Korean government declared "Eurasia Initiative". The initiative proposes important developing projects and ultimately plans to build a peaceful community throughout Eurasia based on comprehensive cooperation. The initiative aims to increase exchanges in transportation, energy and agricultural sectors to achieve the goals. In this regard, implementing TEIA in Northeast Asia is urgently needed and we have to prepare the strategy for introducing TEIA mechanism. Based on the results of 10 year experience on TEIA projects conducted since 2004, we suggest double-track approaches for developing TEIA mechanism. We continuously need to make an effort to establish a regional TEIA mechanism that all countries legally join, and simultaneously we also have to prepare a process to carry out TEIA for upcoming projects based on bi- or multi-lateral agreements. Practical solutions such as conducting pilot TEIA with relevant countries and developing TEIA guideline for the region could be the first step.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.2
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• pp.101-109
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• 1997

Nine oat(Avena sativa L.) cultivars have been recommended as the govemment recommended forage cultivars since 1984, however, their forage performance and quality have mostly been tested at two locations, such as Suweon in the Middle Northwestem Coast Region and Sunghwan in the Middle Southwestern Coast Region. Therefore, the objective of this experiment was to retest the forage performance and quality of six government recommended oat cultivars at five scattered locations, such as Icheon, Suweon, Sunghwan, Keongsan and Kwangju fom 1992 to 1994 with the intention of improving recommendations to dairy farmers. Among the oat cultivars tested, "West" was the highest yielding cultivar at all locations in 1992-94, but the lowest yielding cultivars varied by location and year. At both Icheon and Suweon, "Cayuse", "Magnum" and "Foothill", at Sunghwan, "Cayuse" , "Ensiler" and "Foothill", at Keongsan, "Magnum", "Cayuse" and "Swan", and at Kwangju, "Cayuse", "Magnum" and "Cayuse", were the lowest yielding cultivars in 1993, 1994 and 1995, respectively. At all locations in 1992-94, "West" and "Swan" were the most advanced in growth stage, but "Cayuse", "Foothill", "Magnum" and "Ensiler" were the latest developing cultivars among the oats. Differences among the oat cultivars for the three-year mean NDF, ADF and IVDMD were small and inconsistent, but forage quality of the oats was generally lowest in the early developing cultivars and highest in the late developing cultivars. The govemment recommended oat cultivars tested were generally well adapted across the country, however, in forage production situations in the fall where high yield is more important, early maturing oat cultivars might be preferable to late cultivars because they have higher forage yield earlier in the fall.ction situations in the fall where high yield is more important, early maturing oat cultivars might be preferable to late cultivars because they have higher forage yield earlier in the fall.

• Molecules and Cells
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• v.37 no.4
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• pp.330-336
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• 2014

Thymosin beta4 (TB4) has multiple functions in cellular response in processes as diverse as embryonic organ development and the pathogeneses of disease, especially those associated with cardiac coronary vessels. However, the specific roles played by TB4 during heart valve development in vertebrates are largely unknown. Here, we identified a novel function of TB4 in endothelial-mesenchymal transformation (EMT) in cardiac valve endocardial cushions in zebrafish. The expressions of thymosin family members in developing zebrafish embryos were determined by whole mount in situ hybridization. Of the thymosin family members only zTB4 was expressed in the developing heart region. Cardiac valve development at 48 h post fertilization was defected in zebrafish TB4 (zTB4) morpholino-injected embryos (morphants). In zTB4 morphants, abnormal linear heart tube development was observed. The expressions of bone morphogenetic protein (BMP) 4, notch1b, and hyaluronic acid synthase (HAS) 2 genes were also markedly reduced in atrio-ventricular canal (AVC). Endocardial cells in the AVC region were stained with anti-Zn5 antibody reactive against Dm-grasp (an EMT marker) to observe EMT in developing cardiac valves in zTB4 morphants. EMT marker expression in valve endothelial cells was confirmed after transfection with TB4 siRNA in the presence of transforming growth factor ${\beta}$ ($TGF{\beta}$) by RT-PCR and immunofluorescent assay. Zn5-positive endocardial AVC cells were not observed in zTB4 morphants, and knockdown of TB4 suppressed TGF-${\beta}$-induced EMT in ovine valve endothelial cells. Taken together, our results demonstrate that TB4 plays a pivotal role in cardiac valve formation by increasing EMT.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.3
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• pp.277-290
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• 2009

This paper aims to draw essential facts of network city, to analyze the urban corridor in South-East region, Korea, as a network city. Firstly, the characteristics of the network city is examined theoretically. The global economy is developing an innovative class of network cities. A network cities evolve when two or more previously independent cities, potentially complementary in function, strive to cooperate and achieve significant scope economies aided by-fast and reliable transport and communications infrastructure. Network Cities place a higher priority on knowledge-based activities like research, education and the creative arts. Each constituting city stands to benefit from the synergies of interactive growth via reciprocity, knowledge exchange and unexpected creativity. Secondly, we discussed the network structure of cities in South-East region, Korea itself intensively. We survey the network location and outline of the urban corridor in South-East region, spatial specialization and interaction between the constituting cities. We also discussed the problems of the network cities in South-East region, Korea and introduced the desirable policies and alternatives. We can ascertain from the case study of cities in South-East region that the cities in South-East region corresponds the network city model fairly.

• Progress in Superconductivity and Cryogenics
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• v.17 no.4
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• pp.34-37
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• 2015

Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8-13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

• Journal of Ocean Engineering and Technology
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• v.19 no.1 s.62
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• pp.14-19
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• 2005

As a basic study for establishing the input conditions of a forecasting/estimating model, used for deep-sea water drainage to the ocean, this study was carried out as follows: 1) estimating the amount of river discharge and pollutant loads into the developing region of deep sea water in the East Sea, Korea, 2) a field observation of tidal current, vertical water temperature, and salinity distribution, 3) 3-D numerical experiment of tidal current to analyze the physical oceanographic status. The amount of river discharge flowing into this study area was estimated at about $462.7{\times}103 m\^3/day$ of daily mean in 2002. Annual mean pollutant load of COD, TN, and TP were estimated at 7.02 ton-COD/day, 4.06 ton-TN/day, and 0.39 ton/day, respectively. Field observation of tidal current normally shows 20-40cm/sec of current velocity at the surface layer, and it decreases under 20cm/sec as the water depth increases. We also found a stratification condition at around 30m water depth in the observation area. The differences in water temperature and salinity, between the surface layer and the bottom layer, were about 18 C and 0.8 psu, respectively. On the other hand, we found a definite trend of 34 psu salinity water mass in the deep sea region.