• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.11-19
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• 2001

This review discusses the effects and roles of insect hormones and insect growth regulators (IGRs) on vitellogenesis in adult insects. Insect vitellogenesis is regulated by hormones such as juvenile hormone (JH), ecdysteroids, and neurosecretory hormones (ovaryecdysteroidogenic hormone : OEH) released by neurosecretory cells, diet, and other elements(male specific protein of sperm fluid). In the fat bodies, the vitellogenins are synthesized by the stimulation of JH released by corpus allatum (CA) and ecdysteroids produced by follicle cells with the ovary in most insects. Furthermore, vitellogenins are released into the hemolymph, transported to the ovarioles by carrier protein, and incorporated into oocytes for the developing ovary. Of IGRs, juvenile hormone and its mimics such as methoprene and pyriproxifen appear to have pharmacological effects such as membrane lysis, destruction of salivary grand and midgut epithlial cells, fat body cells, and ovarian tissue, and also anti-juvenile hormone such as precocenes I and II appear to have specific cytotoxicity such as inhibition of corpus allatum and oocytes development. These results suggest that IGRs may be useful as agents for integrated pest management.

• Journal of Biomedical Engineering Research
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• v.38 no.3
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• pp.116-122
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• 2017

Physical breast phantoms would be useful for the development of a dedicated breast computed tomography (BCT) system and its optimization. While the conventional breast phantoms are available in compressed forms, which are appropriate for the mammography and digital tomosynthesis, however, the BCT requires phantoms in uncompressed forms. Although simple cylindrical plastic phantoms can be used for the development of the BCT system, they will not replace the roles of uncompressed phantoms describing breast anatomies for a better study of the BCT. In this study, we have designed a numerical voxel breast phantom accounting for the random nature of breast anatomies and applied it to the 3D printer to fabricate the uncompressed anthropomorphic breast phantom. The numerical voxel phantom mainly consists of the external skin and internal anatomies, including the ductal networks, the glandular tissues, the Cooper's ligaments, and the adipose tissues. The voxel phantom is then converted into a surface data in the STL file format by using the marching cube algorithm. Using the STL file, we obtain the skin and the glandular tissue from the 3D printer, and then assemble them. The uncompressed breast phantom is completed by filling the remaining space with oil, which mimics the adipose tissues. Since the breast phantom developed in this study is completely software-generated, we can create readily anthropomorphic phantoms accounting for diverse human breast anatomies.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.651-655
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• 2008

It provides a three-dimensional virtual experience consisting of information presented to and perceived by the senses of the user. Recently, the advent of a virtual avatar, which mimics the appearance and behavior of humans, enable that the virtual reality (VR) can provide not only a virtual space but also a virtual society to be interact with a virtual avatar which represents humans. But, it is impossible that the user directly interacts with the VE in previous studies, though direct interactions occur in real social relationship. Therefore, In this study, we know that the cognition about a avatar when the user directly interacts with the virtual avatar in the VE. In order to investigate this purpose, we performed a fMRI study using VE that a avatar accept or reject the user's offer when the user offer his (or her) hand to a avatar. In result of questionnaire about the user's feeling by avatar's action, the user feels about avatar's acceptance action that the avatar acts positively and suitably. In contrast the user feels about avatar's rejective action that the avatar acts negatively and disapprovingly. In result of fMRI analysis, the primary visual area, the visual association area, the SMA, the premotor area, the cerebellum and etc, activate in common with the other avatar's acceptance action and rejective action. The results show that the subject recognizes not only avatars as social objects but also avatar's action as socially meaningful action. In other words, it is possible to transfer social context and emotion through avatar's action.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.173-179
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• 2000

Effects of Estradiol-$17\beta(E_2)$ and 2, 4-dichlorophenoxy acetic acid (2, 4-D) on vitellogenin(VTG) production were investigated in primary hepatocyte culture of olive flounder, Paralichthys olivaceus. Highest survival rate of hepatocyte were observed at $27^{\circ}C$, which markedly declined equal to 50% of those of $15^{\circ}C$. Vitellogenin production peaked at the concentration of $10^{-6}M\;E_2$. No effect was observed on VTG production at various concentrations of 2, 4-D. However, a low concentration of 2, 4-D (ie, $10^{-8}M$) only appeared increased VTG production. $E_2$ or $10^{-8}M$ 2, 4-D-primed VTG production was markedly inhibited by the addition of $10^{-6}M$ tamoxifen to the culture medium(P<0.01). Inhibition was not affected by combinational treatment with $10^{-6}M$ $E_2$ and $10^{-6}M$ 2, 4-D. These results from the current investigation suggest that 2, 4-D mimics $E_2$, but the mechanism of reaction in inducing the $E_2$ receptor are different in VTG production in oliver flounder hepatocytes.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.129-132
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• 2002

The practical virtual compensator, which uses a dynamic multi-leaf collimator (dMLC) and three-dimensional radiation therapy planning (3D RTP) system, was designed. And the feasibility study of the virtual compensator was done to verify that the virtual compensator acts a role as the replacement of the physical compensator. Design procedure consists of three steps. The first step is to generate the isodose distributions from the 3D RTP system (Render Plan, Elekta). Then isodose line pattern was used as the compensator pattern. Pre-determined compensating ratio was applied to generate the fluence map for the compensator design. The second step is to generate the leaf sequence file with Ma's algorithm in the respect of optimum MU-efficiency. All the procedure was done with home-made software. The last step is the QA procedure which performs the comparison of the dose distributions which are produced from the irradiation with the virtual compensator and from the calculation by 3D RTP. In this study, a phantom was fabricated for the verification of properness of the designed compensator. It is consisted of the styrofoam part which mimics irregular shaped contour or the missing tissues and the mini water phantom. Inhomogeneous dose distribution due to the styrofoam missing tissue could be calculated with the RTP system. The film dosimetry in the phantom with and without the compensator showed significant improvement of the dose distributions. The virtual compensator designed in this study was proved to be a replacement of the physical compensator in the practical point of view.

• Childhood Kidney Diseases
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• v.15 no.2
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• pp.184-190
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• 2011

Scrotal involvement has been reported from 2% to 38% of males with Henoch-Sch$\ddot{o}$nlein purpura (HSP). It may present before the rash occurs or even long time after it has disappeared. Scrotal involvement of HSP usually results in pain, tenderness, swelling or discoloration of scrotum. Scrotal pain sometimes mimics testicular torsion to various degrees, which can be followed by unnecessary operation. In our 2 cases, one was a 5-year and 11-month-old boy who came to our emergency department due to scrotal pain before the diagnosis of HSP, and the other was a 5-year and 1-month-old boy who came to the outpatient clinic due to scrotal pain after the resolution of HSP about 1 month before the visit. We performed Doppler ultrasonography (USG) to evaluate the acute scrotal pain in the two boys. On Doppler USG, epididymis showed increased blood flow, and testis showed normal blood flow. These findings enabled the diagnosis of acute epididymitis and excluded testicular torsion. Epididymitis was improved by conservative management including shortterm steroid therapy within 5 days. It is important to perform adequate evaluation with tools such as Doppler USG in the early course of acute scrotum of HSP, to avoid unnecessary scrotal exploration.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5B
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• pp.467-474
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• 2011

Debris flow is one of the most hazardous natural processes in mountainous regions. The degradation of discharge capacity of drainage facilities due to debris flows may result in damages of properties and casualty as well as road. Understanding and accurate reproducing flow behaviour of debris flows at various conditions, such as sediment volume concentration and approaching channel and culvert slopes, are prerequisite to develop advanced design criteria for drainage facilities to prevent such damages. We carried out a series of laboratory experiments of debris flows in a rectangular channel of constant width with an abrupt change of bottom slope. The experimental flume consists of an approaching channel part with the bed slope ranging $15^{\circ}$ to $30^{\circ}$ and the test channel with slope ranging from $0^{\circ}$ to $12^{\circ}$ which mimics a typical drainage culvert. The experiments have been conducted for 22 test cases with various flow conditions of channel slopes and sediment volume concentration of debris flows to investigate those effects on the behaviour of debris flows. The results show that, according to sediment volume concentration, the depth of debris flow is approximately 50% to 150% larger than that of fresh water flow at the same flow rate. Experimental results quantitatively present that flow behaviour and deposit history of debris flows in the culvert depend on the slopes of the approaching and drainage channels and sediment volume concentration. Based on the experimental results, furthermore, a logistic model is developed to find the optimized culvert slope which prevents the debris flow from depositing in the culvert.

• BMB Reports
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• v.46 no.6
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• pp.316-321
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• 2013

Gastric cancer remains the main cause of cancer death all around the world, and upregulated activation of the nonreceptor tyrosine kinase c-SRC (SRC) is a key player in the development. In this study, we found that expression of Src is also increased in clinical gastric cancer samples, with the protein level increased more significantly than that at the RNA level. Further study revealed that miR34a and miR203, two tumor suppressive miRNAs, inversely correlate with the expression of Src. Restoration of miR34a and miR203 decreased Src expression in gastric cancer cell lines, which in turn inhibited cell growth and cell migration. In summary, our study here revealed that posttranscriptional regulation of Src contributes to the deregulated cell growth and metastasis in gastric cancer, and targeting Src by miR34a or miR203 mimics would be a promising strategy in therapy.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.83-89
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• 2001

Recent advances in the structural and molecular biology uncovered that a set of translation factors resembles a tRNA shape and, in one case, even mimics a tRNA function for deciphering the genetic ：ode. Nature must have evolved this 'art' of molecular mimicry between protein and ribonucleic acid using different protein architectures to fulfill the requirement of a ribosome 'machine'. Termination of protein synthesis takes place on the ribosomes as a response to a stop, rather than a sense, codon in the 'decoding' site (A site). Translation termination requires two classes of polypeptide release factors (RFs)： a class-I factor, codon-specific RFs (RFI and RF2 in prokaryotes; eRFI in eukaryotes), and a class-IT factor, non-specific RFs (RF3 in prokaryotes; eRF3 in eukaryotes) that bind guanine nucleotides and stimulate class-I RF activity. The underlying mechanism for translation termination represents a long-standing coding problem of considerable interest since it entails protein-RNA recognition instead of the well-understood codon-anticodon pairing during the mRNA-tRNA interaction. Molecular mimicry between protein and nucleic acid is a novel concept in biology, proposed in 1995 from three crystallographic discoveries, one, on protein-RNA mimicry, and the other two, on protein-DNA mimicry. Nyborg, Clark and colleagues have first described this concept when they solved the crystal structure of elongation factor EF- Tu：GTP：aminoacyl-tRNA ternary complex and found its overall structural similarity with another elongation factor EF-G including the resemblance of part of EF-G to the anticodon stem of tRNA (Nissen et al. 1995). Protein mimicry of DNA has been shown in the crystal structure of the uracil-DNA glycosylase-uracil glycosylase inhibitor protein complex (Mol et al. 1995; Savva and Pear 1995) as well as in the NMR structure of transcription factor TBP-TA $F_{II}$ 230 complex (Liu et al. 1998). Consistent with this discovery, functional mimicry of a major autoantigenic epitope of the human insulin receptor by RNA has been suggested (Doudna et al. 1995) but its nature of mimic is. still largely unknown. The milestone of functional mimicry between protein and nucleic acid has been achieved by the discovery of 'peptide anticodon' that deciphers stop codons in mRNA (Ito et al. 2000). It is surprising that it took 4 decades since the discovery of the genetic code to figure out the basic mechanisms behind the deciphering of its 64 codons.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.480-494
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• 2013

Globally branded culture festival in the region as a key component to the originality and distinction and with local residents and visitors to share experience and has succeeded in branding through Mind. Than mimics festivals in competitive and differentiated cultures containing festivals create a unique festival brand, and through the cultural and economic competitiveness, as well as the phase of the World Festival and preserve local culture and identity. Developing The best areas will be an asset. In order to build this world-class festival brand differentiation strategy above all, must be a top priority, Discrimination discovery and development of the local culture and sensibility in the age of the most powerful marketing tool that is being presented through storytelling brand assets to be passed on to visitors should. Thus the creation of storytelling festivals. Sensitivity of the festival right direction and in an era of paradigm key drivers of the local economy, such as image enhancement, and building long-term regional development and differentiation based on quality of life by creating a local culture can improve will Region's cultural and economic areas, the most important resource for the success of the festival is uniformly short-term planning and configuration, tube-driven operating as a one-sided non-participation. Sharing. Communication with an emphasis on the application of storytelling that is essential is considered.