• The Korean Journal of Zoology
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• v.38 no.3
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• pp.405-416
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• 1995

The testis and the epididymis of sexually mature male bats were examined to investigate the process of spermiogenesis of Korean long-fingered bat (Miniopterus schreifersi fulignosus) using electron microscope. The ultrastructural findings were analysed on the basis of Lee's method (1992). Especially, we focused on the acrosome formation. The results are as follows: The spermiogenesis of the Korean long-fingered bat can be divided into ten phases on the basis of ultrastructural differentiation; three "Golgi" phases of early, mid and late stages, two "cap" and two "acrosome" phases respectively composed of early and late phases, one "maturation phase and two "spermiation" phases of early and late phases. The axoneme of sperm in the cauda epididymis is composed of nine outer dense fiber and a central singlet. The number 1, 5, 6, and 9 outer dense fibers are larger than others. In the Golgi phases, small vesicles are separated from Golgi vesicles and then appear to fuse into a large vesicle, and finally it contacd with the outerside of the nucleus. It suggests that proacrosomal material could be made in the cytoplasm before the Golgi vesicle formation and then it could be transferred into the Golgi vesicle and condensed more and more, and finally form acrosome, just as Lee;s suggestion (1992).m acrosome, just as Lee;s suggestion (1992).

• Food Science of Animal Resources
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• v.30 no.5
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• pp.787-794
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• 2010

Calcium plays a role as a signaling molecule in various cellular events. It has been reported that calcium suppresses adipocyte differentiation only in the early phase of adipogenesis. Herein, we demonstrate that treatment of A23187, a mobilizer of intracellular calcium, on day 4 post adipocyte differentiation could still reduce lipid accumulation in differentiating 3T3-L1 cells for 48 h. In addition, luciferase reporter gene and RT-Q-PCR assays demonstrate that A23187 can selectively inhibit transcriptional activities and expression of PPAR$\gamma$ and LXR$\alpha$, suggesting that A23187 may reduce lipid accumulation in the late phase of adipogenesis via downregulation of PPAR$\gamma$ and LXR$\alpha$ expression and transactivation. Moreover, inhibition of HDAC activity by trichostatin A (TSA) partially blocked A23187-mediated downregulation of transcriptional activities of PPAR$\gamma$ and LXR$\alpha$. Together, our data demonstrate that calcium mobilization inhibits expression and transcriptional activities of PPAR$\gamma$ and LXR$\alpha$, resulting in reduced lipid accumulation in differentiating adipocytes, and thus, mobilization of intracellular calcium in adipocytes may serve as a new preventive and therapeutic approach for obesity.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.543-554
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• 2004

Analysis of multi-channel seismic reflection and well data serves to detail the structural evolution of the northern Okinawa Trough, southern offshore Korea. The overall structural style of the area is characterized by a series of half grabens and tilted fault blocks bounded by basement-involved listric normal faults. Most half grabens and tilted fault blocks developed in the direction of NNE-SSW, parallel to the axis of the Okinawa Trough. Orientation and distribution of the listric faults also suggest the development of transfer faults in NW-SE direction. The rifting phase of the northern Okinawa Trough have been established on the basis of structural and stratigraphic analyses of depositional sequences and their seismic expressions. Major phase of rifting probably started in the Late Miocene and the most active rifting occurred during the Early Pliocene. The rifting produced a series of half grabens and tilted fault blocks bounded by listric normal faults. It appears that the rifting activity has become weaker since the Late Pliocene, but the Pleistocene sediments faulted by listric faults bounding tilted fault blocks suggest that the rifting activity is probably still in progress.

• Applied Microscopy
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• v.31 no.3
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• pp.245-256
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• 2001

The morphological characteristics of spermatogenic cells during the spermiogenesis of Paradoxornis webbiana were studied by transmission electron microscope. Spermiogenesis of P. webbiana was divided into ten phase. The chromatin granules became fibrous granules at the Golgi phase, gradually condensed at the cap phases, condensed as a stick at the acrosomal phase, and finally, a perfect nucleus was formed at the maturation phase. The formation of sperm tail began at the early Golgi phase, and completed at the late maturation phase. In particular, the dense materials existed in the sperm neck, which is wedged between the tip of segmented columns and the first mitochondria of the middle piece. The axone in the neck were surrounded by the dense materials. The axonema in spermatozoon contains a 9+2 arrangement of microtubules: 9 doublets, and 2 central single microtubules. Mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the $15^{\circ}$ angled-helical structure. The outer membrane of mitochondria were surrounded by microtubules in plasma membrane of the sperm. The undulating membrane had a helical structure, and the sperm plasma membrane was surrounded by undulating membrane.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.59.2-59.2
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• 2018

We introduce a new project of constructing a large spectro-photometric samples of metal-poor (i.e. [Fe/H] < -1.0) subdwarfs in the Galactic halo. The sample is collected from a compilation of the stellar objects that are cross-identified both in the Sloan Digital Sky Survey (SDSS) and recently published data from GAIA mission. The color range of the selected stars covers 0.0 < (g-r) < 2.0; thus the spectral types of our sample span from early F- through late K-type stars on the metal-poor main sequence (i.e. the local subdwarf sequence). We scrutinized the physical, chemical, and kinematical properties of our samples using their SDSS medium-resolution (R ~ 2000) spectra, combined with accurately measured proper motions from GAIA satellite. Our study will provide useful information on the global trend in the various properties (e.g. abundance pattern as a function of the galactocentric distance; rotational velocity vs [Fe/H] ${\cdots}$ etc) of the metal-poor subdwarf populations in the Galactic halo, which is ultimately important to better understand metal-poor stellar evolutionary models and chemical evolution of the Milky Way halo in the early phase of its formation. Further our comprehensive catalog of the Galactic field halo subdwarfs collected in this study will serve a solid groundwork for future follow-up high resolution spectroscopic observations on many interesting individual targets.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.559-565
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• 1998

This study was conducted to investigate the effects of different feeding regimen on the growth and nutrients excretion in finishing pigs. A total of 80 pigs (59.91 kg BW) and 6 pigs (85 kg BW) were employed in a growth trial and metabolic trial, respectively. Treatments were grower-grower (GG), grower-early finisher(GE), early finisher-early finisher (EE), and early finisher-late finisher (EL) diet feeding regimens for feeding trial and G, E, L diets for metabolic trial. Through whole experimental period, no significant difference was found in any of the criteria measured. Pigs fed on a GG regimen gained slightly faster than pigs fed on other feeding regimens, with no significant difference. Although there was a trend that pigs fed on a GG or GE regimen showed improved feed/gain over pigs fed on a EE or EL regimen, the difference also was not significant. In the metabolic trial, dry matter and phosphorus digestibility was not affected by diets, however, phosphorus digestibility tended to be decreased as nutrients contents was decreasing in the diets. Crude protein digestibility was significantly influenced by the nutrients contents in th diets. The data suggested that 11.7% crude protein seemed to be low for the 85 kg pigs. Though nutrients excretion was not significantly influenced by dietary treatment except phosphorus, there was a trend that pigs fed diets with low nutrient content excreted less amount of nitrogen and phosphorus than pigs fed diets with high nutrients content. There was a trend that GG or GE feeding regimen gad a favorable effect on carcass grade when only 10 lighter pigs of each treatment were subjected to statistical analysis. However, with 10 heavier pigs, EE and EL feeding regimen showed better carcass grade, though the difference was not significant. In summary, it seemed that producers generally oversupply the expensive nutrients for the finishing pigs. High nutrient diets do not always guarantee high growth rate of pigs. It rather seems that to meet nutrient requirements for the each growth phase is more important in economical pork production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.391-395
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• 1999

Barnyardgrass had relatively higher growth vigor at the earlier growth stage than inbred rice did, showing the 2 fold higher $\alpha$-amylase activity during the periods of germination and large leaf area Expansion with high net photosynthetic rate at the earlier autotrophic stage, but it performed weak growth at the late growth stage. However, the hlybrid rice Shanyou 63 had significantly higher $\alpha$-amylase activity and net photosynthetic rate than that of barnyardgrass, exhibiting heterosis for two physiologica1 traits during the germination (6~12 days) and autotrophic phase, respectively. Accordingly, hybrid rice, Shanyou 63, exhibited heterotic effect at the early growing stage when were presented with barnyardgrass. Shanyou 63 exhibited stronger tillering ability, faster leaf area expansion and higher net photosynthetic rate than those of barnyardgrass.

• Korean Institute of Interior Design Journal
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• no.22
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• pp.69-76
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• 2000

Contemporary architecture in Japan is entering an entirely new phase in the second half of the 1980s. In the late 1960s, doubts began to be expressed about Modernism, which until then had been the recognized mainstream of architecture. There was much discussion, but it was only in the early '80s that an active debate was initiated concerning Post-Modernism. Today, however, matters have gone beyond this, and the situation appears particularly significant. The Japanese architecture world was hitherto understand to be fundamentally very different from its western counterparts. There are several trends in current Japanese architecture which have still come out of the Japanese tradition of life, culture, region, climate itself. At the same time, stance of contemporary Japanese architecture start from a common basis in world's design stream which can be called Post-Modernism, Deconstructivism, Neo-Modernism. This study is aimed at analysis of 'Regional Characteristics' in Contemporary Japanese Architecture.

• KSBB Journal
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• v.11 no.1
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• pp.107-114
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• 1996

The enhancing effect of excreted cell factors on the production of somatic embryos from suspension cultures of Daucus carota was studied as a function of factors including molecular size, harvesting time, injection period, and concentration of the extracellular compounds. The production of late-stage embryos was increased up to 1, 500 embryos/ml compared with control cultures when high molecular size and extracellular factors, extracted from newly established embryo culture at early stationary phase, were added at the starting time. The stimulating effect on the production of somatic embryos can be attributed to the presence of high molecular size(> 10 kDa) compounds.

• The Transactions of the Korea Information Processing Society
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• v.7 no.4
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• pp.1112-1121
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• 2000

Design metrics that quantify the design phase play an important role in reducing system development cost because the problems in early phases of software development seriously affected the quality of the late products. Real-time systems such as telecommunication systems are so large that design quantification is more important in real-time system design. Although many metrics have been proposed, few of them are correctly validated. This paper revises the SDL metrics set proposed in earlier study [9] and perform an analytical validation o the metrics set. Axiomatic approach and dimensional analysis are used for metrics validation and the old metrics are revised ot satisfy the validation criteria.