• Journal of Aquaculture
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• v.7 no.4
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• pp.189-205
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• 1994

Formerly, adult-tiger puffer, Takifugu rubripes with ova caught in the sea, were used for seedling production. But it was difficult to secure naturally-ripened adults. For the purpose of adult tiger puffer in captivity, this study was carried out. To determine the growth 220 tiger puffers hatched in 1990 (3-year-old) and 1991 (2-year-old) were used. For spawning and egg incubation leading to fry development, eggs were stripped from tiger puffers hatched in 1988 (5-year-old) and 1990 (3-year-old) through human chorionic gonadotropin (BCG) treatments. In May, 1993, mean body length and mean body weight of 2-year-old tiger puffer were $30.72\pm1.35cm\;and\;1,048\pm228 g,$ and that of 3-year-old tiger puffers were $36.02\pm1.17cm$ and $1,402\pm66g$ respectively. The relationship between body length (L) and body weight (W) of 2-year-old the tiger puffers during the experiment period was represented as $W\;=\;1.7892L^{31524}\times10^5$ (r= 0.9436) and that of 3-year-old, $W=\;3.2840L^{36099}\times10^6$ (r= 0.9070) respectively. The GSI in female 2-year-old-fish changed from $0.23\times0.l2\;to\;0.74\pm0.08$, during the experiment period, and in male it didn't change remarkably until November, but thereafter it increased and showed a peak of $8.69\pm5.09$. The GSI of 3-year-old-fish showed a peak of $8.05\pm5.58$ in April in female and $12.65\pm4.60$ in May in male. The change of HSI in 3-year-old-fish was correlative to the change of GSI, but in 2-year-old-fish it was little correlative. In female gonad of 2-year-old tiger puffer, the mature oocytes reached $350{\mu}m$ in April, but thereafter they didn't spawn and became atrophied. But in male gonad, a great number of spermatozoa were crowded in the testicular lobuli in April. Female gonad of 3-year-old tiger puffer had the mature oocytes of 650 pm in March and the ripe oocytes, $900{\mu}m$ in April. Male testis development was similar to that of 2-year-old-fish. Egg-stripping after hormone treatments was possible past 139 hours and 142 hours from each of two 5-year-old-fish (500IU/kg, BW), and after 114 hour from a 3-year-old-fish (1,000 IU/kg, BW) under water temperature $16.3\~17.8^{\circ}C$. Eggs stripped amounted was 650 g and 400 g from two 5-year-old-fish and 610 g from the 3-year-old-fish, and fertilization rates were $98.0\%,\;97.4\%\;and\;96.5\%$ respectively. All the hatched larvae devloped into normal fry.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.9-14
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• 2006

Milk yield and its quality traits determine the dairy enterprise profitability and sustainability. Milk quality traits including somatic cell counts (SCC) is an upcoming economic challenge for dairy farming community in Korea. This study estimated the effect of parity, stage of lactation (early, mid and late lactation) on SCC, stress (blood cortisol) and immunity (blood IgG, lymphocyte and neutrophil) traits, their heritabilities and genetic correlations between them. SCS and blood neutrophil count were significantly affected by both parity and stage of lactation, however; IgG was affected by only stage of lactation, and blood cortisol and lymphocyte were not affected by both factors. The SCS has shown increasing trend with the parity, however; the difference between first and second parity, second and third parity were not significant. The SCS in early (≤90 days) and late lactation (181≤days) were higher than that of mid lactation (91～180 days). Cortisol concentration in blood was lowest in fourth parity, however; the differences among the first three parties were not significant. The IgG was higher in fourth parity compare with first parity however; all other comparisons were noted non-significant. The IgG concentration was significantly higher in early lactation than those of mid and late lactation. The blood lymphocytes were decreased with increasing parity however the differences beyond second parity were not significant. The neutrophils were increased with the increasing lactation stage however; the difference between early and mid lactation was not significant. Although heritability of SCS was still lower, but it was meaningful value (0.09) and may be considered to improve milk quality. The genetic correlations between SCS and cortisol (-0.96), and lymphocyte (-0.76) were highly negative. Heritability of cortisol was low, however genetic correlations between cortisol and lymphocyte (0.79) was highly positive. IgG with medium heritability was correlated negatively with lymphocyte (-0.88) and neutrophil (-0.98). Lymphocyte was lowly heritable and highly correlated with neutrophil concentration (0.87).This study suggested that cortisol, IgG, lymphocyte and neutrophil being positively genetically correlation with somatic cell score could be used as alternative traits to enhance milk quality in Holstein cattle. Further studies are warranted to estimate genetic relationships between immunological and production traits to increase the genetic merit of Holstein cows for milk yield, to improve animal health and economic viability under intensive management system.

• Korean journal of communication and information
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• v.61
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• pp.74-97
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• 2013

Asia is developing rapidly in 21st century. Human and material exchanges between Korea and Asian countries have greatly increased. Korea entered the multicultural society. It became important for Korean people to understand Asia more correctively. Korean media can play a key role for this. In this point, I analyzed 1786 news contents reported in 2011 by four Korean newspapers(Chosun Ilbo, Dong-A Ilbo, Hankyoreh newspaper, Kyungh Kyunghyang Daily News), to see differences of Asia and West news aspect and its reason, focusing on news topic, amount of news, news tone and foreign media sources. In amount of news, the percent of West(54.3%) was higher than that of Asia news(45.7%). In news tone, negative news were the most in Asia news, but the least in West news. Korean newspaper showed more positive attitude to West than Asia. 1786 news were classified into seven topics(morality and justice, politics, economics and science, society, diplomacy and national defense, human interest, people). In news amount of seven topics, Korean newspapers reported hard news like morality and justice more than soft news like human interest about Asia. However they reported many soft news about West besides hard news. In news topics and tone, hard news showed negative tone most and soft news showed neutral or positive tone most. As a result, Korean news showed the negative attitude to Asia and the positive to West. Among five main sources(media, government, private organization, individual and material), only media source affected the differences of news attitude to Asia and West. Asia media source took the more positive attitude to Asia than West. West media took the negative attitude to Asia most and the neutral attitude to West most. Korean newspapers used West media as main sources in the news of all areas except East Asia. As a result, Korean newspapers showed the West-centered-attitude and reported the negative news more than neutral and positive about Asia. It was suggested that Korean newspapers had better increase Asia news in diverse spheres by the direct reporting of the correspondent and the more use of Asia media through the internet.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.9-16
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• 2013

An experiment was conducted to evaluate the biochemical adverse effect of increased carbon dioxide in seawater on marine polychaete, Perinereis aibuhitensis. We measured the available energy reserves, Ea (total carbohydrate, protein, and lipid content) and the energy consumption, Ec (electron transport activity) of Perinereis aibuhitensis exposed for 7-d to a range of $CO_2$ concentration such as 0.39 (control =390 ppmv), 3.03 (=3,030 ppmv), 10.3 (=10,300 ppmv), and 30.1 (=30,100 ppmv) $CO_2$ mM, respectively. The cellular energy allocation (CEA) methodology was used to assess the adverse effects of toxic stress on the energy budget of the test organisms. The results of a decrease in CEA effect of increased carbon dioxide in seawater from all individual in Ea and Ec. Increase of carbon dioxide reduced pH in seawater, significantly. The chemical changes in sea- water caused by increasing $pCO_2$ might cause stresses to test organisms and changes in the cellular energy allocations. Results of this study can be used to understand the possible influence of $CO_2$ concentration increased by the leakage from sub-sea bed storage sites as well as fossil fuel combustion on marine organisms.

• Progress in Medical Physics
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• v.25 no.3
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• pp.151-156
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• 2014

The purpose of this study was to confirm the feasibility of imaging of therapy region from the boron neutron capture therapy (BNCT) using the measurement of the prompt gamma ray depending on the neutron flux. Through the Monte Carlo simulation, we performed the verification of physical phenomena from the BNCT; (1) the effects of neutron according to the existence of boron uptake region (BUR), (2) the internal and external measurement of prompt gamma ray dose, (3) the energy spectrum by the prompt gamma ray. All simulation results were deducted using the Monte Carlo n-particle extended (MCNPX, Ver.2.6.0, Los Alamos National Laboratory, Los Alamos, NM, USA) simulation tool. The virtual water phantom, thermal neutron source, and BURs were simulated using the MCNPX. The energy of the thermal neutron source was defined as below 1 eV with 2,000,000 n/sec flux. The prompt gamma ray was measured with the direction of beam path in the water phantom. The detector material was defined as the lutetium-yttrium oxyorthosilicate (Lu0,6Y1,4Si0,5:Ce; LYSO) scintillator with lead shielding for the collimation. The BUR's height was 5 cm with the 28 frames (bin: 0.18 cm) for the dose calculation. The neutron flux was decreased dramatically at the shallow region of BUR. In addition, the dose of prompt gamma ray was confirmed at the 9 cm depth from water surface, which is the start point of the BUR. In the energy spectrum, the prompt gamma ray peak of the 478 keV was appeared clearly with full width at half maximum (FWHM) of the 41 keV (energy resolution: 8.5%). In conclusion, the therapy region can be monitored by the gamma camera and single photon emission computed tomography (SPECT) using the measurement of the prompt gamma ray during the BNCT.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.201-210
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• 2017

BACKGROUND: The current study was to monitor of 9 veterinary antibiotics (ceftiofur, clopidol, florfenicol, sulfamethazine, sulfamethoxazole, sulfathiazole, tetracycline, tiamulin, and tylosin) in manure using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive and negative electrospray ionization mode. METHODS AND RESULTS: Sample preparation was carried out using Mcllvaine buffer and citrate salts to adjust the pH of the sample followed by purification with dispersive solid phase extraction (d-SPE). Separation of analytes during LC-MS/MS analysis was conducted using an Eclipse Plus $C_{18}$ column and the mobile phase was in gradient mode with, 0.1% formic acid and 5 mM ammonium formate in methanol (A) and 0.1% formic acid and 5 mM ammonium formate in distilled water (B). The linearity of the matrix-matched calibrations of all tested antibiotics was good, with $R^2$ determination coefficients ${\geq}0.9920$. The limit of detection (LOD) and quantifications (LOQ) were $0.1-67.0{\mu}g/kg$ and $0.4-200.0{\mu}g/kg$, respectively. Analysis of 13 solid and liquid manure samples taken from the Republic of Korea revealed concentrations less than $0.7{\mu}g/kg$ for tiamulin, $1497.6{\mu}g/kg$ for sulfamethazine. CONCLUSION: To monitor 9 veterinary antibiotics from manure samples in 13 provincial areas throughout the Republic of Korea, an analytical method was developed. The developed method was fully validated and successfully applied for monitoring various veterinary antibiotics in manure samples.

• Archives of design research
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• v.20 no.3 s.71
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• pp.29-38
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• 2007

The competition to capture a larger slice of the market in Mobile Communication business is increasing among companies. In order to achieve and maintain a competitive advantage in the Asian market, it is critical to continue to develop new technology. Understanding the underlying distinctive characteristics and needs of each market and the cultural backgrounds that drive those needs is a necessary focus. Companies with marketing strategies based on a correct understanding of market needs will capture dominant positions in the market. The purpose of this study is to identify those differences in user behavior and cultural tendencies among different people in different countries in the mobile telecommunication market. This research is based on an on-line survey in three countries (Korea, China, and Japan). Below are the contents of the survey on the mobile phone based on: 1) User behavior 2) Design preference 3) Purchasing behavior 4) User awareness on manufacturer brand. Through the analysis of this questionnaire it is possible to identify the differences and similarities among countries dearly. 1) Cultural trends and perceptions related to mobile phone usage were largely caused by differences in the state of technology, policies and business strategies of mobile sonics carriers and manufacturers, and national tendencies, of each country. 2) Korean and Japanese users produced similar responses to the questions related to advanced technology, whereas Korean and Chinese users responded similarly to national tendency-related questions. 3) To the questions related to business strategies of mobile service carriers and manufacturers, users in all three countries displayed markedly different responses. Once again, accurate analysis of the differences and similarities related to mobile phone usage in each country will help the companies in this industry to gain a competitive edge in the market. This study should not stop at simple comparison but be a framework for giving companies a dear future direction for technological development.

• Journal of Environmental Science International
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• v.3 no.3
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• pp.273-284
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• 1994

The primary objective of this study was to examine the toxic effects of PCP on activated sludge and to analyze its metabolic responses while treating wastewater containing pentachlorophenol (PCP) in a sequencing batch reactor (SBR) system operating under different control strategies. This study was conducted in two phases 1 and 2 (8-hr and 12-hr cycles). Each phase was operated with two control strategies I and II. Strategy I (reactor 1) involved rapid addition (5 minutes to complete) of substrate to the reactor with continuous mixing but no aeration for 2 hours. Strategy ll (reactor 2) involved adding the feed continuously during the first 2 hours of the cycle when the system was mixed but not aerated. During both phases each reactor was operated at a sludge age of 15 days. The synthetic wastewater was used as a feed. The COD of the feed solution was about 380 mg/l. After the reference response for both reactors was established, the steady state response of each system was established for PCP feed concentrations of 0.1 mg/l, 1.0 mg/l, and 5.0 mg/l in SBR systems operating on both 8-hr and 12-hr cycles. Soluble COD removal was not inhibited at any feed PCP concentrations used. At 5.0 mg/l fined PCP concentration and in SBR systems operating on phase 2, the concentrations of MLVSS were decreased; selective pressure on the mixed biomass might be increased, narrowing the range of possible ecological responses; the settleability of activated sludge was poor; the SOURS were increased, showing that the systems were shocked. Nitrification was made to some extent at all concentrations of feed PCP in SBR systems operating on phase 2 whereas in SBR systems operating on phase 1 little nitrification was observed. Then, nitrification will be delayed as much as soluble COD removal is retarded due to PCP inhibition effects. Enhanced biological phosphorus removal occurring in the system operating with control strategy I during phase 1 of this work and in the presence of low concentrations of PCP was unreliable and might cease at anytime, whereas enhanced biological phosphorus removal occurring in the system operating with either control strategy I or II during phase 2 of this work and in the Presence of feed PCP concentrations up to 1.0 mg/l was reliable. When, however, such processes were exposed to 5.0 mg/l PCP dose, enhanced phosphorus removal ceased and never returned.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.1
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• pp.44-52
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• 2012

Purpose: In this paper we tried to evaluate the most appropriate surface for rhBMP-2 coating among 4 rough titanium surfaces. Materials and methods: We used machined surface as a control group and anodized, RBM and SLA surfaces as test groups. We coated rhBMP-2 on the 4 surfaces and with uncoated surfaces for each case, we cultured human mesenchymal stem cells on all 8 surfaces. 24 hours after we measured the stem cell' attachment with SEM, and on 3rd, 7th, and 14th days, we checked the cell proliferation and differentiation by using MTT and ALP activity assay. And on the 7th day after the culture, we performed RT-PCR assay to determine whether the expression levels of Type I collagen, osteocalcin, osteopontin were changed. Results: We observed with SEM that 4 rhBMP-2 coated surfaces exhibited wider and tighter cell attachment and more cell process spreading than uncoated surfaces. The anodized rhBMP-2 surface caused robustest effects. In MTT assay we could not find any meaningful difference. In ALP assay there was a significant increase (P<.05) in the ALP activity of anodized rhBMP-2 coated surface compared with that of the control (3rd and 14th days) and with that of the RBM rhBMP-2 coated surface (14th day). In RT-PCR assay there was increased expressions in the anodized rhBMP-2 coated surface for osteocalcin, and osteopontin. Conclusion: We found that the anodized rhBMP-2 coated surface were most prominent stem cell attachment and differentiation in compared to control and Machined rhBMP-2 coated, RBM rhBMP-2 coated surface.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.283-305
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• 2001

The purpose of this study was to analyze the stress distribution of condylar regions and edentulous mandible with implant-supported cantilever prostheses on the certain conditions, such as amount of load, location of load, direction of load, fixation or non-fixation on the condylar regions. Three dimensional finite element analysis was used for this study. FEM model was created by using commercial software, ANSYS(Swanson, Inc., U.S.A.). Fixed model which was fixed on the condylar regions was modeled with 74323 elements and 15387 nodes and spring model which was sprung on the condylar regions was modeled with 75020 elements and 15887 nodes. Six Br${\aa}$nemark implants with 3.75 mm diameter and 13 mm length were incorporated in the models. The placement was 4.4 mm from the midline for the first implant; the other two in each quardrant were 6.5 mm apart. The stress distribution on each model through the designed mandible was evaluated under 500N vertical load, 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. The load points were at 0 mm, 10 mm, 20 mm along the cantilever prostheses from the center of the distal fixture. The results were as follows; 1. The stress distribution of condylar regions between two models showed conspicuous differences. Fixed model showed conspicuous stress concentration on the condylar regions than spring model under vertical load only. On the other hand, spring model showed conspicuous stress concentration on the condylar regions than fixed model under 250N horizontal load linguobuccally, buccal 20 degree 250N oblique load and buccal 45 degree 250N oblique load. 2. Fixed model showed stress concentration on the posterior and mesial side of working and balancing condylar necks but spring model showed stress concentration on the posterior and mesial side of working condylar neck and the posterior and lateral side of balancing condylar neck under vertical load. 3. Fixed model showed stress concentration on the posterior and lateral side of working condylar neck and the anterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior sides of working and balancing condylar necks under horizontal load linguobuccally. 4. Fixed model showed stress concentration on the posterior side of working condylar neck and the posterior and lateral side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 20 degree oblique load. 5. Fixed model showed stress concentration on the anterior and lateral side of working condylar neck and the posterior and mesial side of balancing condylar neck but spring model showed stress concentration on the anterior side of working condylar neck and the anterior and lateral side of balancing condylar neck under buccal 45 degree oblique load.. 6. The stress distribution of bone around implants between two models revealed difference slightly. In general, magnitude of Von Mises stress was the greatest at the bone around the most distal implant and the progressive decrease more and more mesially. Under vertical load, the stress values were similar between implant neck and superstructure vertically, besides the greatest on the distal side horizontally. 7. Under horizontal load linguobuccally, buccal 20 degree oblique load and buccal 45 degree oblique load, the stress values were the greatest on the implant neck vertically, and great on the labial and lingual sides horizontally. After all, it was considered that spring model was an indispensable condition for the comprehension of the stress distributions of condylar regions.