• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.183-189
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• 1995

In human IVF-ET, the development and morphology of the embryo have been known to affect implantation and pregnancy rates(PRs). Recently, pregnancy has been reported to related to the embryos with thick zona-pellucida, high levels of fragmentation, poor blastomere development and zona hardening. Although the mechanism of implantation is unclear, it is thought that the hatching process precedes implantation and that the hatching is related to implantation and PRs. This study was carried out to investigate the effect of assisted hatching(AHA) on the improvement of PRs in human IVF-ET. The results were as follows; 1. The PRs of the AHA group (40.8%) was significantly higher than that of control group(27.2%)(P<0.01). 2. According to the age of patients, the PRs of control and AHA groups were 33.9%(20/59), 44,4%(12/27) in <30 yrs, 26.1%(30/115), 38.3%(18/47) in 31-35 yrs, 22.4%(13/58), 41.4%(12/29) in >36 yrs, respectively. 3. According to the factors of infertility in AHA group, unexplained(immunologic factor) (40.0%) and male factors(41.9%) were higher than female(tubal obstruction, endometriosis, adhesion) factor (28.9%). As a result, it is suggested that AHA technique improve the PRs in poor prognosis patients. It is concluded that AHA method can be used to improve the PRs in human lVF-ET.

• Journal of Environmental Impact Assessment
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• v.21 no.3
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• pp.391-407
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• 2012

The loss of connectivity and fragmentation of forest landscapes are seriously hindering dispersal of many forest-dwelling species, which may be critical for their viability and conservation by decreasing habitat area and increasing distance among habitats. For understanding their environmental impacts, numerous spatial models exist to measure landscape connectivity. However, general relationships between functional connectivity and landscape structure are lacking, there is a need to develop landscape metrics that more accurately measure landscape connectivity in whole landscape and individual patches. We reviewed functional and structural definition of landscape connectivity, explained their mathematical connotations, and applied representative 13 indices in 3 districts of Seoul having fragmented forest patches with tits, the threshold distance was applied 500m by considering the dispersal of tits. Results of correlation and principal component analysis showed that connectivity indices could be divided by measurement methods whether they contain the area attribute with distance or not. Betweenness centrality(BC), a representative index measuring distance and distribution among patches, appreciated highly stepping stone forest patches, and difference of probability of connectivity(dPC), an index measuring including area information, estimated integrated connectivity of patches. Therefore, for evaluating landscape connectivity, it is need to consider not only general information of a region and species' characteristics but also various measuring methods of landscape connectivity.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.200-206
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• 2017

The damage and fragmentation of habitat due to urbanization pose a great threat to amphibians worldwide. To understand the effect of urbanization on the distribution and abundance of Hyla japonica, we measured their population sizes by listening frog calling and investigated the habitat their population sizes and land use in the 18 rice paddy fields located in Incheon and its surroundings. Abundance of H. japonica was 0 - 17 male adults / habitat or 0 - 41 male adults / ha in Incheon. The number of the frog was increased as the distance between the habitat and the road became longer or the ratio of circumstance / area of the habitat increased. Unlike the general prediction, the density of H. japonica showed a negative correlation with the size of the habitat and a positive correlation with the surrounding land use intensity. Our results suggested that H. japonica could be concentrated in a narrow habitat due to the habitat size decrease and the periphery development according to the urbanizaion.

• Journal of Korean Neurosurgical Society
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• v.38 no.5
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• pp.366-374
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• 2005

Objective : Nitric oxide[NO] is implicated in a wide range of biological processes in tumors and is produced in glioma. To investigate the role of NO and its interaction with the tumoricidal effects of anticancer drugs, we study the antitumor activities of NO donors, with or without anticancer drugs, in human glioma cell lines. Methods : U87MG and U373MG cells were treated with the NO donors sodium nitroprusside[SNP] and S-nitroso-N-acetylpenicillamine[SNAP], alone or in combination with the anticancer drugs 1,3-bis[2-chloroethyl]-1-nitrosourea[BCNU] and cisplatin. Cell viability, cell proliferation, DNA fragmentation, nitrite level, and the expression of Bcl-2 and Bax were determined. Results : NO was markedly increased after treatment with SNP or SNAP; however, the addition of the anticancer drugs did not significantly affect NO production NO donors or anticancer drugs reduced glioma cell viability and, in combination, acted synergistically to further decrease cell viability in a dose- and time-dependent manner. Cell proliferation was inhibited and apoptosis were enhanced by combined treatment. Bax expression was increased by combined treatment, whereas Bcl-2 expression was reduced. The antitumor cytotoxicity of NO donors and anticancer drugs differed according to cell type. Conclusion : BCNU or cisplatin can inhibit cell viability and proliferation of glioma cells and can induce apoptosis. These effects are further enhanced by the addition of a NO donor which modulates the antitumor cytotoxicity of chemotherapy depending on cell type. Further biological, chemical, and toxicological studies of NO are required to clarify its mechanism of action in glioma.

• Journal of Korean Neurosurgical Society
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• v.37 no.2
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• pp.129-136
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• 2005

Objective: Currently available therapies for human malignant gliomas have limited efficacy. Toxoplasma gondii, an obligate intracellular protozoan parasite, and Quil-A are nonspecific, potent immune stimulants. T. gondii is shown to have antitumor activity in some types of cancers. Therefore, this study is undertaken to evaluate the antitumor effect of Toxoplasma lysate antigen (TLA), alone or in combination with Quil-A, on human glioma U373MG and U87MG cells. Methods: The in vitro effects of TLA alone or in combination with Quil-A on the proliferation, invasion, and apoptosis of glioma cells were tested using MTT, Matrigel invasion, and DNA fragmentation assays, and the in vivo effects on the growth of gliomas were evaluated in athymic nude mice transplanted with glioma cells. Results: Treatment with TLA resulted in the suppressed proliferation and invasion of both U373MG and U87MG cells, in a dose-dependent manner. In addition, at high concentration, TLA induced glioma cell apoptosis. When TLA was administered in the mouse glioma model, malignant glioma growth was decreased. The combined treatment of TLA with Quil-A significantly inhibited the proliferation and invasion of cultured cells as well as tumor mass of implanted mice. Conclusion: TLA inhibits the proliferation and invasion of glioma cells in vitro and in vivo, and these antitumor effects of TLA are significantly enhanced by the addition of Quil-A.

• Archives of Craniofacial Surgery
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• v.17 no.4
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• pp.181-185
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• 2016

Panfacial bone fracture is challenging. Even experienced surgeons find restoration of original facial architecture difficult because of the severe degree of fragmentation and loss of reference segments that could guide the start of facial reconstruction. To restore the facial contour, surgeons usually follow a general sequence for panfacial bone reduction. Among the sequences, the bottom-to-top and outside-in sequence is reported to be the most widely used in recent publications. However, a single sequence cannot be applied to all cases of panfacial fractures because of the variations in panfacial bone fracture patterns. In this article, we intend to find the reference and discuss the efficacy of inside-out sequence in facial bone fracture reconstruction.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2S
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• pp.711-720
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• 2000

BADA-IV/XML is a system designed specifically for managing XML. Documents and is essential to various electronic document applications as a fundamental system. BADA-IV/XML supports all of aspects of data model, querying and manipulation operations for managing XML documents. This paper provides an overview of these aspects of the BADA-IV/XML, as well as defines schema classes for stroing, querying and maintaining hierarchical semantics of multimedia documents and structural semantics of complex documents linked with each other, Also a multimedia document query language is designed and implemented to support essential operations for efficient searching and managing multimedia documents. Finally, some simulation results show the performance of the paged VF(Virtual Fragmentation) model and the search model using element's identifier as compared with a general model.

• Journal of The Korean Astronomical Society
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• v.34 no.4
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• pp.181-190
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• 2001

The advent of robust, reliable and accurate higher order Godunov schemes for many of the systems of equations of interest in computational astrophysics has made it important to understand how to solve them in multi-scale fashion. This is so because the physics associated with astrophysical phenomena evolves in multi-scale fashion and we wish to arrive at a multi-scale simulational capability to represent the physics. Because astrophysical systems have magnetic fields, multi-scale magnetohydrodynamics (MHD) is of especial interest. In this paper we first discuss general issues in adaptive mesh refinement (AMR), We then focus on the important issues in carrying out divergence-free AMR-MHD and catalogue the progress we have made in that area. We show that AMR methods lend themselves to easy parallelization. We then discuss applications of the RIEMANN framework for AMR-MHD to problems in computational astophysics.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.513-524
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• 2009

Urban land consolidation, which is to reform land parcels to remove fragmentation and produce ideal blocks, is an effective means for urban renewal. Successful urban land consolidation brings out great benefits to the city officials as well as general public, such as improved city image, increased land value, and more effective land use. However, urban land consolidation can be detrimental to environment, especially in the ecological aspects, while the execution of land consolidation has been focused solely on development for the sake of human benefits. To remove negative effects of urban land consolidation to the ecological system, this paper is intended to establish a set of criteria for evaluating ecological impacts of an urban land consolidation plan. Firstly, key ecological indicators are identified using a special group decision-making process called "habitual domain analysis" and then individual weighting of each indicator is recorded by analytical hierarchy process. An urban ecological evaluation model with 4 levels and 23 indicators is thus developed.

• Journal of Ginseng Research
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• v.28 no.1
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• pp.39-44
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• 2004

The present study is to determine whether the Red-ginseng extract has a proliferative or cytotoxic effect on the human neuronal stem cells(hNSCs). The hNSCs were grown and incubated with different doses of Red-ginseng extract. We tested the proliferative or cytotoxic effects by MTT and FACS analysis. Cell viability cell cycle analysis, DNA fragmentation, and bax or PARP expressions were evaluated. The hNSCs showed a proliferafe trend with its peak concentration at 0.3 $\mu\textrm{g}$/$m\ell$. Beyond this point, higher doses decreased viabilities and showed a cytotoxic effect at 10 $\mu\textrm{g}$/$m\ell$. There was a tendency of increased S and G2/M phases during cell proliferation. In a cytotoxic condition, decreased S phase and increased G0/G1 phases were noted, suggesting cell cycle arrest. The cytotoxic effect was associated with increase DNA fragmentation in a dose-dependent manner, However PARP cleavage or bax expression was not detected. Our results suggest that Red-ginseng extract has dual effects, the cell proliferative or cytotoxic effect, on hNSCs in vitro with dose-dependent manner.