• Journal of Radiation Protection and Research
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• v.8 no.1
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• pp.1-14
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• 1983

For the purpose of prediction and protection of radiation effects on the Korean people, we have collected autoptic data from the National Institute of Scientific Investigation. The mass of organs and the size of brains measured is analysed for 1,921 Korean people. The results obtained are as follows; 1. The weight of the kidney in the Reference Korean is 251.6g in male and 227.7g in female. 2. The weight of the lung in the Reference Korean is 1,204.4g in male and 957.4g in female. 3. The weight of the heart in the Reference Korean is 348.8g in male and 301.6g in female. 4. The weight of the liver in the Reference Korean is 1,863.9g in male and 1,610.9g in female. 5. The weight of the pancreas in the Reference Korean is 56.4g in male and 54.0g in female. ,6. The weight of the spleen in the Reference Korean is 67.3g in male and 58.2g in female. 7. The anteroposterior diameter, transverse diameter and vertical diameter of the brain in the Reference Korean are 17.6cm, 15.5cm and 8.6cm in male, respectively, and 17.7cm, 15.4cm and 8.2cm in female, respectively.

• Journal of the Korean Chemical Society
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• v.50 no.6
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• pp.494-505
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• 2006

This study was performed for 7th grade students to analyze by leader style, the verbal interactions between students in a small group in an MBL(Microcomputer-Based Laboratory) experiment class. The study was performed after arranging the students into four kinds of groups, including groups with leaders of inclusive, persuasive, and alienating styles and a group with no clear leader. The analysis of total frequencies of verbal interaction revealed that the group with an inclusive leader showed the highest frequency of verbal interaction, followed by the group with a persuasive leader, an alienating leader and lastly, the group with no clear leader. The group with an inclusive leader showed the highest frequency of interaction from a cognitive aspect related to question(Q), response(R), making suggestion(MS), and receiving opinions(RO), while interactions from an affective aspect related to behavioral participation(BP) and students' attitudes(SA) were observed more often in a group including an alienating leader than in any other group. An analysis of characteristics of verbal interaction according to leader style showed that a group with an inclusive leader had a permissive atmosphere. It also showed that all members of the group actively participated in discussion and they had a sense of belonging and self-pride with their group. In a group with a persuasive leader, the leader took the lead of most experimental and discussion activities and he was rarely challenged by other students in the group. Rather, other group members showed a tendency to depend on their leader. In a group with an alienating leader, the relationship between leader and members of the group was not harmonious and unfiltered expressions of dissatisfaction and ignorance often took place. The leader's lack of concern about members' low achievement became an obstacle in active discussion. In a group with no clear leader, most interactions during discussion were short and simple. Many answers to the question given by their members were not clear and the interactions were sometimes interrupted for a short while.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.29-36
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• 2010

This experiment was conducted to evaluate the influence of phase feeding methods on growth performance, carcass characteristics, pork quality, and economical efficiency in growing-finishing pigs. A total of 120 crossbred pigs ([Yorkshire ${\times}$ Landrace] ${\times}$ Duroc), average initial body weight 25.23 ${\pm}$ 2.66 kg, were allotted to 5 treatments by body weight and sex in a randomized complete block (RCB) design. Each treatment had 6 replicates with 4 pigs per pen. The treatments were 1) A (fed late weaner feed during whole phase), 2) B (fed late weaner feed in growing phase and grower feed in finishing phase), 3) C (fed grower feed during whole phase), 4) D (fed grower feed in growing phase and early finisher feed in early and late finishing phase), 5) E (fed grower feed in growing phase, early finisher feed in early finishing phase and late finisher feed in late finishing phase). Commercial diets bought from private feed company were used for this experiment. During the early growing phase (6 wks), treatments A and B showed higher growth performance than that of other treatments (P<0.05). However, growth performance tended to be similar among treatments at 10 wks after feeding and there was no difference in time of market weight (13 wks). Moreover, blood urea nitrogen (BUN) concentration was lowered in treatment E than other treatments during whole experimental period (P<0.01). Carcass characteristics and pork quality were measured when body weight of pigs reached at 110.33 ${\pm}$ 2.1 kg. Days to market weight (110 kg), quality grade, pork color, and pork pH did not show any significant difference among treatments. These results suggested that phase feeding based upon growth stages of pigs showed no detrimental effects on growth performance and the pork quality. Moreover, feed cost was saved approximately 37% by phase feeding method without delaying of days to market weight compared to general conventional feeding method (B) of swine farm in Korea.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.43-49
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• 1998

The aim of this study were to measure and compare the stress level on three type brackets and each other material (stainless steel, ceramic) with tipping and torquing forces by using the finite element analysis and to design biomechanically favorable brackets. For this study, three kinds of brackets were selected(A:Transcend-RMO, B:Signature-Unitek, C:PAW: plain archwire appliance-applied for a patent in Yonsei Udiversity). The slot size of bracket was 0.022inch and the size of archwire was 0.0175x0.025inch and taper shaped archwire was used in PAW. Loading force in tipping was 4.27N and torquing force was 32.858N applied by archwire torsion with 19.7degree and 11.3 degree in C type bracket. The conclusions were that (1) The finite element method proved to be a useful tool in the stress analysis of orthodontic bracket subjected to various forces. (2) With tipping, the stresses were concentrated at the gingival wall of the wire slot where it meets the mesial bracket surface and the incisal wall of the wire slot where it meets the distal bracket surface and with torquing, the stresses were concentrated at the junction of the gingival or incisal wall and base of the slot. (3) The maximum stress value was higher in torquing force than tipping force and therefore it is desirable to design on the basis of torquing force. (4) It was considered that the change in material might be affect on the diminish of stress value in the place of stess concentration. (5) The maximum stress value was highest on PAW bracket when the tipping and torquing force was applied and therefore it would be desirable to use mechanically favorable material on PAW bracket.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.3
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• pp.174-183
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• 2014

Seabed beneath and near coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using the expanded 2-dimensional numerical wave tank to account for an irregular wave field. In the condition of an irregular wave field, the dynamic wave pressure and water flow velocity acting on the seabed and the surface boundary of the composite breakwater structure were estimated. Simulation results were used as input data in a finite element computer program for elastoplastic seabed response. Simulations evaluated the time and spatial variations in excess pore water pressure, effective stress, and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the results of the analysis, the liquefaction potential at the seabed in front and rear of the composite breakwater was identified. Since the liquefied seabed particles have no resistance to force, scour potential could increase on the seabed. In addition, the strength decrease of the seabed due to the liquefaction can increase the structural motion and significantly influence the stability of the composite breakwater. Due to limitations of allowable paper length, the studied results were divided into two portions; (I) focusing on the dynamic response of structure, acceleration, deformation of seabed, and (II) focusing on the time variation in excess pore water pressure, liquefaction, effective stress path in the seabed. This paper corresponds to (II).

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.3
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• pp.160-173
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• 2014

Seabed beneath and near coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using the expanded 2-dimensional numerical wave tank to account for an irregular wave field. In the condition of an irregular wave field, the dynamic wave pressure and water flow velocity acting on the seabed and the surface boundary of the composite breakwater structure were estimated. Simulation results were used as input data in a finite element computer program for elastoplastic seabed response. Simulations evaluated the time and spatial variations in excess pore water pressure, effective stress, and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the results of the analysis, the liquefaction potential at the seabed in front and rear of the composite breakwater was identified. Since the liquefied seabed particles have no resistance to force, scour potential could increase on the seabed. In addition, the strength decrease of the seabed due to the liquefaction can increase the structural motion and significantly influence the stability of the composite breakwater. Due to limitations of allowable paper length, the studied results were divided into two portions; (I) focusing on the dynamic response of structure, acceleration, deformation of seabed, and (II) focusing on the time variation in excess pore water pressure, liquefaction, effective stress path in the seabed. This paper corresponds to (I).

• Progress in Medical Physics
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• v.27 no.1
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• pp.31-36
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• 2016

The paper discusses radiation dose of dual energy CT on which copper modulation layer, is mounted in order to improve diagnostic performance of the dual energy CT. The radiation dose is estimated using MCNPX and its results are compared with that of the conventional dual energy CT system. CT X-ray spectra of 80 and 120 kVp, which are usually used for thorax, abdominal, head, and neck CT scans, were generated by the SPEC78 code and were used for the source specification 'SDEF' card for MCNPX dose modeling. The copper modulation layer was located 20 cm away from a source covering half of the X-ray window. The radiation dose was measured as changing its thickness from 0.5 to 2.0 mm at intervals of 0.5 mm. Since the MCNPX tally provides only normalized values to a single particle, the dose conversion coefficients of F6 tally for the modulation layer-based dual energy CBCT should be calculated for matching the modeling results into the actual dose. The dose conversion coefficient is $7.2*10^4cGy/output$ that is obtained from dose calibration curve between F6 tally and experimental results in which GAFCHORMIC EBT3 films were exposed by an already known source. Consequently, the dose of the modulation layer-based dual energy cone beam CT is 33~40% less than that of the single energy CT system. On the basis of the results, it is considered that scattered dose produced by the copper modulation layer is very small. It shows that the modulation layer-based dual energy CBCT system can effectively reduce radiation dose, which is the major disadvantage of established dual energy CT.

• Applied Microscopy
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• v.32 no.4
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• pp.385-398
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• 2002

The purpose of the present study is to investigate whether stromal cells supporting specific microenvironment for hematopoiesis of bone marrow are affected by toxicants and therapeutic drugs such as antibiotics and anticancer drugs and whether laminin-1 is associated with such effects. SD rats were intraperitoneally injected with 75 mg/kg of cyclophosphamide which is widely used to treat infant's solid tumor, leukemia and myeloma and sacrificed after 3 days, 1 week, 3 weeks or 5 weeks of injection. The bone marrow extracted and paraffin-sectioned was analyzed using immunohistochemical staining. A part of tissues was subjected to electron microscopy following reaction with rabbit anti-laminin antibody, biotinylated goat anti-rabbit IgG conjugated with 12 nm gold particles, and staining with uranyl acetate. 1. The bone marrow tissue at day 3 post injection with cyclophosphamide displayed dilated venous sinus, partial necrotic death, and decreased number of hematopoietic cells. Laminin-1 was intensively stained in the reticular and adipose tissues. 2. Up to 5 weeks post injection, laminin-1 was stained at a low level in the stromal tissue of bone marrow and the number of hematopoietic cell was increased. 3. Deposition of the gold particle which represents laminin-1 expression was observed at the highest level in the stromal cells of bone marrow obtained 3 days after injection, and decreased after 1 to 5 weeks. These results suggest that stromal cells which play a role in supporting microenvironment for bone marrow hematopoiesis augment induction of laminin-1 expression and activation upon administration of cyclophosphamide.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.4
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• pp.291-302
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• 1998

The purpose of this study is to clarify the effect of plant growth regulator "Uniconazole-P" on the control of growth and seed producrtion of pasture plants under grown in sward conditions. Four species examined were orchard grass, timothy, red clover and alfalfa. Uniconazole-P concentrations were control(0), 20ppm and 40ppm, and foliar sprayed on canopy structures at the floral differentiation stages of grasses and at the begining of flowering stages of legumes, respectively. 1. Yield components and seed yield components of grasses and legumes were responded differently between Uniconazole-P concentrations, species and the stages of growth. 2. At early heading stages, the plant length and culm length of grasses were reduced by Uniconazole-P treatments. On the contrary, the dry weight of ears per area and chlorophyll concentrations were increased by Uniconazole-P treatments. 3. At seed ripening stages, the number of ears, dry weight of a tiller, dry weight of a ear, dry weight of ears per area and dry weight of seeds in orchardgrass, and the number of ears, dry weight of a ear, dry weight of ears per area, dry weight of seeds and harvest index in timothy were increased by Uniconazole-P treatments. 4. At early flowering stages, the plant length and total length of internodes were reduced by Uniconazole-P treatments. On the contrary, total length of branches and chlorophyll concentrations of red clover and alfalfa were increased by Uniconazole-P treatments. Particularly, the number of inflorescences and dry weight of inflorescences of red clover was increased greatly by Uniconazole-P treatments. 5. At seed ripening stages, the plant length of both of legumes were reduced by Uniconazole-P treatments. On the contrary, the dry weight of a inflorescence, dry weight of inflorescences per area, dry weight of seeds and harvest index of alfalfa was increased by Uniconazole-P treatments. 6. Seed production of grasses by Uniconazole-P treatments can be explained as following processes at each stage of growth. 1) reduced in plant length and culm lengths at early heading stages, 2) increased in number of ears and dry weight of a ear at both of stages, and 3) increased in dry weight of ears per area, dry weight of seeds and harvest index at seed ripening stages. 7. Seed production of legumes by Uniconazole-P treatments can be explained as following processes at each stage of growth. 1) reduced in plant length and total length of internodes and increased in number of branches and total length of branches at early flowering stages, 2) increased in number of inflorescences and dry weight of inflorescences at both of stages, and 3) increased in dry weight of seeds and harvest index at seed ripening stages.

• Journal of Life Science
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• v.25 no.9
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• pp.993-999
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• 2015

The beetle Popillia flavosellata has been no reported its functional effects. In this study, we investigated the anti-inflammatory effect of P. flavosellata ethanol extract (PFE) on RAW 264.7 mouse macrophage cells treated with lipopolysaccharide (LPS) for the induction of inflammation. First, we examined the cytotoxicity of PFE in the RAW 264.7 cells at a concentration of 2,000 μg/ml or less. To evaluate the anti-inflammatory effects of PFE, we investigated the expression levels of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6, and proinflammatory enzymes, such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-induced RAW 264.7 cells. In addition, we examined whether PFE inhibited the translocation of nuclear factor kappa B (NF-κB) p65 into the nucleus in the LPS-induced RAW 264.7 cells. We found that the protein levels of TNF-α and IL-6 were decreased in the LPS-induced RAW 264.7 cells after the treatment with PFE in a dose-dependent manner. In addition, we confirmed that PFE inhibited the translocation of NF-κB p65 into the nucleus, as well as the protein expression levels of iNOS and COX-2. Accordingly, we propose that PFE exerts an anti-inflammatory effect through the down-regulation of NF-κB p65, TNF-α, IL-6, iNOS, and COX-2 via the toll like receptor (TLR)-4 inflammatory signaling pathway.