• 한국해양학회지
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• v.26 no.1
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• pp.67-76
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• 1991

Masan Bay is infamous for its severe eutrophication, exemplified by frequent red tide incidences and anoxic conditions. We carried out daily observations for 16 days at one site immediately after the summer rainy season in 1988 on the basis that shorter observation intervals be necessary to observe a process with high turnover rate. in spite of the relatively short survey period, we could observe dramatic changes in abundance and composition of the phytoplankton populations. Cell densities and chlorophyll concentrations changed in the magnitude of 70 and 10 times, respectively, Skeletonema costatum, a diatom species, dominated the first peak of phytoplankton biomass and was followed by Prorocentrum minimum, a dinoflagellate species, which occurred dominantly in the second peak after about a week, form the viewpoint of time scale, we suggest that at least a weekly sampling might be appropriate in complex coastal environments as Masan Bay. While stratification enabled high production in the surface layer, it hindered the transport of silicate from bottom to the surface, which in turn limited the prolonged growth of diatoms. Ensued second peaks of silicate and diatom abundance in the surface layer suggest periodic flux of silicate from bottom across the discontinuity driven by tidal currents.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.583-591
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• 1994

This study was carried out to investigate the pathogenesis of canine herpesvirus(CHV) infection in dogs. The 17 puppies, one day old, delivered from CHV seronegative 3 dams were divided into two groups. The 13 puppies were inoculated intranasally with 1ml of CHV-KK inoculum($5{\times}10^{5.6}TCID_{50}/ml$) and 4 puppies were served as control. And then the puppies were sacrificed at 2, 4, 6 and 7 days after the treatment, and sampled nasal mucosa, trigeminal nerve, trigeminal ganglion, bone marrow, eye, brain and other major organs for the immunohistochemical examination. Distribution of CHV antigens was limited in cytoplasms and nuclei of necrotic nasal epthelia at 2 days after infection. At 4 days after infection, CHV antigens were detected in vascular walls and peripheral nerves of nasal lamina propria, reticuloendothelial cells of spleen, interstitium of kidney, leptomeningeal vascular walls and alveolar walls, At 6 and 7 days after infection, CHV antigens were detected in all of the necrotic area. CHV antigens were also detected in vascular endothelial cells of various organs and in blood leukocytes from 4 days after infection. Among the six puppies in which necrotic lesions of central nervous system were observed, CHV antigens were detected in trigeminal ganglion, trigeminal nerve and ventroposteriomedial nucleus of four puppies and in spinal trigeminal nucleus of three puppies. These results indicate that the generalized focal necrosis of all organs including brain and eyes in canine herpesvirus infection were resulted from generalized vasculitis with leukocyte-associated viremia, and also the hemonecrotizing meningoencephalitis was resulted from spreading of CHV via blood and nerve trunk.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.794-797
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• 2004

In this study, tensile adhesive strength(TAS) test was carreid out for evaluated the effects of temperature conditions (-20, -10, 0, 5, 10, 20, 30, $40^{\circ}C$) on the tensile adhesive characteristics about 4 type waterproofing membranes which were commercially used in bridge decks. And, failure appeariences of waterproofing systems in each temperature after TAS test were observed the sawing surfaces of waterproofing systems for whether or not damaged of waterproofing membranes. Also, correction coefficient of TAS with temperature were calculated using 4 type waterproofing membrane. It could be shown that the higher TAS and shear adhesive strength, the lower temperature, regardless of the type of waterproofing membrane. Temperature sensibility of TAS was especially remarkable in epoxy membrane. Failure type was occurred the ductile failure in $30^{\circ}C\;and\;40^{\circ}C$. From these results, it was shown that if ambient temperature above $30^{\circ}C$ maintains for a long time, waterproofing membrane will be deformed by softening. Otherwise, waterproofing membrane in temperature below $20^{\circ}C$ shown that occurred the brittle failure. From the results of visual observation of cutting surface for specimen, the thin waterproofing membranes shown indented by hot aggregate of the asphalt mixtures. Therefore, it could be known that the specification of waterproofing membrane thickness is necessary by waterproofing membrane type. As temperature change varied with pavement depth, the interface temperature was more important than ambient temperature in TAS test. Now, TAS test results were limited only in $-10^{\circ}C\;and\;20^{\circ}C$ temperature, but correction coefficient of TAS by ambient temperature could be used as a solution to deal with this problem.

• Journal of Korean Elementary Science Education
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• v.36 no.1
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• pp.95-112
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• 2017

The competence of teachers, comes out through their lesson, is one of the key factors of school education. The purpose of this study is comparing the viewpoints on the science lessons in the elementary classrooms between pre-service teachers and highly experienced teachers in order to draw implications on pre-service teacher educating system. The participants of the study are 14 junior students in a university of education and 9 elementary school teachers who are highly educated and have much career experience. Each student participant observed one video clip with science lesson of their classmate. The total number of the video subject to observation is 4. Meanwhile experienced teachers observed 1 or 2 videos which are the same to those the students watched. The participants made a class criticism according to the General Standards for Class Critique made by KICE. The in-depth analysis of the criticism yielded the following conclusions; First, pre-service teachers had narrow views on the science class mainly limited in the practical part of class, but experienced teachers had wide views covered to class-knowledge, plan, and practice. Second, most experienced teachers thought that learning is the process by which students acquire knowledge or concepts by themselves, and the main purpose of the class is to help students' learning. Meanwhile, there were many pre-service teachers who thought that conveying knowledge or concepts to students was the main purpose of the class. Third, experienced teachers thought that a good science class should maintain consistency around the learning goals from the planning, implementation, and evaluation. However, many pre-service teachers did not take the learning objectives so seriously.

• Journal of Advanced Navigation Technology
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• v.18 no.5
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• pp.494-500
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• 2014

Recently the leak of personal information from in-house and contract-managed companies has been continually increasing, which leads a regular observation on outsourcing companies that perform the personal information management system to prevent dangers from the leakage, stolen and loss of personal information. However, analyzing many numbers of computers in limited time has found few difficulties in some circumstances-such as outsourcing companies that own computers that have personal information system or task continuities that being related to company's profits. For the reason, it is necessary to select an object of examination through identifying a high-risk of personal data leak. In this paper, this study will formulate a proposal for the selection of high-risk subjects, which is based on the user interface, by digital forensic. The study designs the integrated analysis tool and demonstrates the effects of the tool through the test results.

• Atmosphere
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• v.22 no.1
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• pp.13-28
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• 2012

The $PM_{10}$ concentration data is useful for indentifying intensity and a transport way of Asian dust. However, it is difficult to identify them properly due to the limited spatial resolution and coverage. Therefore, a methodology to estimate $PM_{10}$ concentration using visibility data obtained from synoptic observation was developed. To derive the converting function, correlation between visibility and $PM_{10}$ concentration is investigated using visibility and $PM_{10}$ concentration data observed at 20 stations in Korea from 2005 to 2009. To minimize bias due to atmospheric moisture, data with higher relative humidity over a critical value were eliminated while deriving $PM_{10}$-visibility relationship. As a result, an exponentially decreasing function of visibility is obtained under the condition that relative humidity is less than 82%. Verification of the visibility converting function to $PM_{10}$ concentration was carried out for the dust cases in 2010. It was found that spatial distributions of $PM_{10}$ calculated by visibility are in good agreement with the observed $PM_{10}$ distribution, especially for the strong dust cases in 2010. And correlation between the derived and observed $PM_{10}$ concentration was 0.63. We applied the function to obtain distributions of $PM_{10}$ concentration over North Korea, in which concentration data are not available, and compared them with satellite derived dust index, IODI distributions for dust cases in 2010. It is shown that the visibility function estimates quite similar patterns of dust concentration with IODI image, which suggests that it can contribute for prediction by indentifying transport route of Asian dust.

• Clinical and Experimental Pediatrics
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• v.58 no.1
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• pp.1-7
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• 2015

Gonadotropin-releasing hormone analogs (GnRHa) are widely used to treat central precocious puberty (CPP). The efficacy and safety of GnRHa treatment are known, but concerns regarding long-term complications are increasing. Follow-up observation results after GnRHa treatment cessation in female CPP patients up to adulthood showed that treatment (especially <6 years) was beneficial for final adult height relative to that of pretreated or untreated patients. Puberty was recovered within 1 year after GnRHa treatment discontinuation, and there were no abnormalities in reproductive function. CPP patients had a relatively high body mass index (BMI) at the time of CPP diagnosis, but BMI standard deviation score maintenance during GnRHa treatment seemed to prevent the aggravation of obesity in many cases. Bone mineral density decreases during GnRHa treatment but recovers to normal afterwards, and peak bone mass formation through bone mineral accretion during puberty is not affected. Recent studies reported a high prevalence of polycystic ovarian syndrome in CPP patients after GnRHa treatment, but it remains unclear whether the cause is the reproductive mechanism of CPP or GnRHa treatment itself. Studies of the psychosocial effects on CPP patients after GnRHa treatment are very limited. Some studies have reported decreases in psychosocial problems after GnRHa treatment. Overall, GnRHa seems effective and safe for CPP patients, based on long-term follow-up studies. There have been only a few long-term studies on GnRHa treatment in CPP patients in Korea; therefore, additional long-term follow-up investigations are needed to establish the efficacy and safety of GnRHa in the Korean population.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.2
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• pp.121-131
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• 2020

Purpose: To determine the long-term efficacy of the anti-tumor necrosis factor (TNF) agents, infliximab (IFX) and adalimumab (ADA), in pediatric luminal Crohn's disease (CD) by performing a systematic literature review. Methods: An electronic search was performed in Medline, Embase, and the Cochrane Library from inception to September 26, 2019. Eligible studies were cohort studies with observation periods that exceeded 1 year. Studies that reported time-to-event analyses were included. Events were defined as discontinuation of anti-TNF therapy for secondary loss of response. We extracted the probabilities of continuing anti-TNF therapy 1, 2, and 3 years after initiation. Results: In total, 2,464 papers were screened, 94 were selected for full text review, and 13 studies (11 on IFX, 2 on ADA) met our eligibility criteria for inclusion. After 1 year, 83-97% of patients were still receiving IFX therapy. After 2 and 3 years the probability of continuing IFX therapy decreased to 67-91% and 61-85%, respectively. In total, 5 of the 11 studies subgrouped by concomitant medication consistently showed that the probabilities of continuing IFX therapy in patients with prolonged immunomodulator use were higher than those in patients on IFX monotherapy. Conclusion: This review of real-world evidence studies confirms the long-term therapeutic benefit of IFX therapy in diverse cohorts of children with luminal CD. Moreover, it supports the view that combination therapy with an immunomodulator prolongs the durability of IFX therapy in patients who previously failed to recover following first-line therapy. The limited number of time-to-event studies in patients on ADA prevented us from drawing definite conclusions about its long-term efficacy.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.539-553
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• 2010

Objectives : The object of this study was to obtain accurate information (single oral dose toxicity) of Lonicerae Flos (LF; Dried flower bud parts of Lonicera japonica Thunb (Caprifoliaceae)), which has traditionally been used in Korean medicine for treating various inflammatory diseases. Methods : In order to observe the 50% lethal dose (LD 50), approximate lethal dosage (ALD) and target organs, test articles were once orally administered to female and male ICR mice at dose levels of 2,000, 1,000, 500 and 0 (control) mg/kg (body weight.). The mortality and changes on body weight, clinical signs and gross observation were monitored for 14 days after single oral treatment of LF aqueous extracts with organ weights and histopathological observations of 12 types of principle organs. Results : 1. After single oral treatment of LF aqueous extracts, we could not find any mortality and toxicological evidences up to 2,000 mg/kg treated group, the limited dosages in rodents at body and organ weights, clinical signs, gross and histopathological observations. 2. Slight diarrhea was detected in most mice treated with 2,000 mg/kg of LF aqueous extracts and male mice of LF aqueous extracts 1,000 mg/kg within 2 days after end of treatment, respectively. Conclusion : The results obtained in this study suggest that the LD 50 and ALD of LF aqueous extracts in both female and male mice after single oral treatment were considered as over 2,000 mg/kg because no mortalities were detected up to 2000 mg/kg, the highest dose recommended by KFDA and OECD. However, we also observed the possibility of digestive disorders like diarrhea when over 1,000 mg/kg of LF aqueous extracts were administered in the present study.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.4
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• pp.453-459
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• 2013

The objective of this study was to evaluate the single oral dose toxicity of Polygalae Radix (PR) in male and female mice. PR extract (yield = 18.6%) was administered to ICR mice as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines (2009-116, 2009). Animals were monitored for the mortality and the changes in body weight, clinical signs and gross observation during 14 days after dosing. Upon necropsy, organ weight and histopathology of 14 principal organs were examined. It was observed that there were no mortalities, clinical signs, changes on the body and organ weights, gross and histopathological observations against 14 principal organs related to PR extract up to 2,000 mg/kg. Therefore, 50% lethal dose ($LD_{50}$) and approximate LD of PR aqueous extracts after single oral treatment in female and male mice were considered over 2000 mg/kg the limited dosages recommended by KFDA Guidelines, respectively.