• Journal of fish pathology
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• v.28 no.3
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• pp.117-123
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• 2015

Economic loss by soft tunic syndrome of edible ascidian, Halocynthia roretzi has become a serious problem. Recently, it has discovered that the cause of this syndrome is infection by a protozoan parasite Azumiobodo hoyamushi. However, only a few studies have been conducted to control this parasitic disease. In a previous research, non-specific disinfectants have been found to be effective in controling the causative parasite. In an attempt to eradicate this causative parasite, organic acids were tested in this study to evaluate their in vitro and in vivo efficacy. In vitro tests showed that 8 different organic acids used in this study were moderately or highly effective with protozoan-killing effects ($EC_{50}=153{\sim}275{\mu}g/ml$). Despite weak in vivo penetration of organic acids into the tunic tissues, treatment with high concentration reduced the mortality of ascidian caused by infection the parasite, indicating that we might be able to develop a disinfection method using environmentally-friendly organic acids.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.440-449
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• 2015

Pine wood nematode (PWN), Bursaphelenchus xylophilus is one of the most serious pests of pine tree. Trunk injection of some nematicides in tree is well known as an effective control method. However there are some limitating factors which hindering the efficacy of trunk injection in field or potted tree. In this study we suggested easy and useful alternative screening methods of nematicides against PWN. Reproduction of PWN was influenced by tree twig moisture (high reproduction in high moisture trig) and paraffin coating was 78.6% reduced moisture loss in tested twig. There were no reproduction different in up and down site from infection site of twig at 1 month after inoculation of PWN and also distance (5 and 10 cm) from inoculation site of PWN did not influence the reproduction of PWN. Numbers of reproduced PWN were higher with decreasing diameter of twig. Numbers of reproduced PWN were similar to P. thunbergii and P. densiflora. However reproduction was increased depending on high inoculation density and longer propagation period. When inoculation of PWN on cut twig injected with emamectin benzoate 2.15% EC and morantel tartrate 8% SL in trunk of Pinus thunbergii in the field, PWN number were significantly reduced than untreated control. We suggest this screening method for PWN control agents.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.235-241
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• 2012

A huge marine accident causes a loss of valuable lives, property and the serious marine environment pollution. IMO adopted resolution A.949(23) to provide Places of Refuge(PoR) to 'Ship in need of assistance', which is to minimize the secondary environmental pollution caused by marine accidents. If the level of risk exceeds a certain range, it is necessary to be designated as Places of Refuge(PoR) after evaluation of potential risk, which is based on the database of several marine environmental factors. Also, it is necessary to develop skills about quantification/standardization of vessel traffic safety, complexity and risk. Because there is the close relation between the problem of designating Places of Refuge(PoR) and the policy of nation for protecting the natural environment of coastal state, it is important to prepare related legislation. In this paper, introduction of Places of Refuge(PoR) in domestic areas have been suggested based on the analysis of several foreign designating cases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.257-265
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• 2020

Parts obsolescence is a component type, in which raw materials or parts that make up a weapons system, are developed and produced according to demand, but they age due to changes in technology or market conditions. The weapon system equipment currently being used by the military is having difficulty in procurement, maintenance, and operation because of the obsolescence of parts. Parts obsolescence during the life cycle of a weapons system affects not only the combat readiness of the military but also the economic loss of material, parts, and equipment manufacturers and suppliers. On the other hand, advanced technology has reduced the life span of electronic components that make up the weapons system. In addition, because of the nature of the weapons system, the obsolescence of components takes decades from development to disposal, which has a serious adverse effect on equipment readiness and life cycle costs. Therefore, it is necessary to manage systematically the parts obsolescence from development until the disposal of the weapons system equipment. This study examined the system of component control in developed countries to present a proper management plan for local situations and propose development plans for the early settlement of component control.

• Journal of Biomedical Engineering Research
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• v.39 no.5
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• pp.220-228
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• 2018

The internal resistance of microbial fuel cell (MFC) using stainless steel skein for oxidizing electrode was investigated and the factors affecting the voltage generation were identified. We also investigated the effect of power management system (PMS) on the usability for MFC and the removal efficiency of organic pollutants. The performance of a stack microbial fuel cell connected with (PMS) or PMS+LED was analyzed by the voltage generation and organic matter reduction. The maximum power density of the unit cells was found to be $5.82W/m^3$ at $200{\Omega}$. The maximum current density was $47.53A/m^3$ without power overshoot even under $1{\Omega}$. The ohmic resistance ($R_s$) and the charge transfer resistance ($R_{ct}$) of the oxidation electrode using stainless steel skein electrode, were $0.56{\Omega}$ and $0.02{\Omega}$, respectively. However, the sum of internal resistance for reduction electrode using graphite felts loaded Pt/C catalyst was $6.64{\Omega}$. Also, in order to understand the internal resistance, the current interruption method was used by changing the external resistance as $50{\Omega}$, $300{\Omega}$, $5k{\Omega}$. It has been shown that the ohm resistance ($R_s$) decreased with the external resistance. In the case of a series-connected microbial fuel cell, the reversal phenomenon occurred even though two cells having the similar performance. However, the output of the PMS constantly remained for 20 hours even when voltage reversal occurred. Also the removal ability of organic pollutants (SCOD) was not reduced. As a result of this study, it was found that buffering effect for a certain period of time when the voltage reversal occurred during the operation of the microbial fuel cell did not have a serious effect on the energy loss or the operation of the microbial fuel cell.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.619-627
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• 2015

BACKGROUND/OBJECTIVES: Colitis is a serious health problem, and chronic obesity is associated with the progression of colitis. The aim of this study was to determine the effects of natural raw meal (NRM) on high-fat diet (HFD, 45%) and dextran sulfate sodium (DSS, 2% w/v)-induced colitis in C57BL/6J mice. MATERIALS/METHODS: Body weight, colon length, and colon weight-to-length ratio, were measured directly. Serum levels of obesity-related biomarkers, triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), insulin, leptin, and adiponectin were determined using commercial kits. Serum levels of pro-inflammatory cytokines including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$, and IL-6 were detected using a commercial ELISA kit. Histological study was performed using a hematoxylin and eosin (H&E) staining assay. Colonic mRNA expressions of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR assay. RESULTS: Body weight and obesity-related biomarkers (TG, TC, LDL, HDL, insulin, leptin, and adiponectin) were regulated and obesity was prevented in NRM treated mice. NRM significantly suppressed colon shortening and reduced colon weight-to-length ratio in HFD+DSS induced colitis in C57BL/6J mice (P < 0.05). Histological observations suggested that NRM reduced edema, mucosal damage, and the loss of crypts induced by HFD and DSS. In addition, NRM decreased the serum levels of pro-inflammatory cytokines, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 and inhibited the mRNA expressions of these cytokines, and iNOS and COX-2 in colon mucosa (P < 0.05). CONCLUSION: The results suggest that NRM has an anti-inflammatory effect against HFD and DSS-induced colitis in mice, and that these effects are due to the amelioration of HFD and/or DSS-induced inflammatory reactions.

• The KIPS Transactions:PartB
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• v.18B no.5
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• pp.315-324
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• 2011

In Web environment, a flood of spam causes serious social problems such as personal information leak, monetary loss from fishing and distribution of harmful contents. Moreover, types and techniques of spam distribution which must be controlled are varying as days go by. The learning based spam classification method using Bag-of-Words model is the most widely used method until now. However, this method is vulnerable to anti-spam avoidance techniques, which recent spams commonly have, because it classifies spam documents utilizing only keyword occurrence information from classification model training process. In this paper, we propose a spam document detection method using a characteristic of repeating words occurring in spam documents as a solution of anti-spam avoidance techniques. Recently, most spam documents have a trend of repeating key phrases that are designed to spread, and this trend can be used as a measure in classifying spam documents. In this paper, we define six variables, which represent a characteristic of word repetition, and use those variables as a feature set for constructing a classification model. The effectiveness of proposed method is evaluated by an experiment with blog posts and E-mail data. The result of experiment shows that the proposed method outperforms other approaches.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.2 no.1
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• pp.39-44
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• 2006

Cerebral palsy(CP) is one of the most common motor disease, due to brain injury during fetal and neonatal development which results in neuromotor paralysis and associated neuromuscular symptoms. Features of CP include motor disability due to the lack of muscle control, often accompanied by sensory disorders, mental retardation, speech disorders, hearing loss, epilepsy, behavior disorders, etc. There are increasing chances of treatment of dental patients with cerebral palsy, as the occurrence of CP is increasing with the decrease in infant mortality and an increase in immature birth and premature birth and also, there is a trend to pursue of higher quality of life. Reports on the relationship between CP and maxillofacial deformity are uncommon, but it is well known that the unbalance and discontrol of the facial muscles, lip, tongue and the jaws leads to malocclusion and temporomandibular joint disorders, and statistics show that class 2 relationship of the jaws and open bite is frequently reported. However, it is difficult to perform maxillofacial deformity treatment, which consists of orthodontic treatment, maxillofacial surgery and muscle adaptation training, due to difficulties in communication and problems of muscle adaptation caused by difficulties in motor control which leads to a high recurrence rate. This case report is to trearment of maxillofacial deformity in CP patient. A 26 year old female patient came to the department with the chief complaint of prognathism of the mandible and facial asymmetry. According to the past medical history, she was diagnosed as cerebral palsy 1 week after birth, classified as GMFC, classII accompanied with left side torticollis. The patient's intelligence was moderate, and there were no serious problems in communication. For two years time, the patient underwent lingual frenectomy, pre-operation orthodontic treatment and then bimaxillary orthognathic surgery to treat mandibular prognathism and facial asymmetry followed by rehabilitatory exercise of facial muscle. After 6 months of follow up, there was a good result. This is to report to the typical signs and symptoms of DFD in CP patient and the limitation of the usual method of the treatment of DFD in CP patient with literature review.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.757-765
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• 2008

Maxillary central incisor impactions occur infrequently. Their origins include various local causes, such as odontoma, supernumerary teeth, space loss, and disturbances in the eruption path, also trauma and apical follicular cysts. Impacted teeth can cause serious dental and aesthetic difficulties as well as psychological problems especially in anterior regions. Although the impaction of maxillary incisor occurs less frequently than that of the maxillary canine, it is of concern to parents during the early mixed dentition stage because of the uneruption of the tooth. Forced eruption of impacted teeth should be considered in young patients because this technique can lead to suitable results from a periodontal, occlusal, and esthetic perspective at an earlier stage better than with other treatment options. This report presents the surgical and orthodontic treatment of cases with horizontally impacted and dilacerated maxillary central incisors. For each patient, we used the closed eruption method, placed an attachment on the impacted tooth on surgery, and fully closed the flap. Traction was applied immediately. The impacted tooth erupts through the healed tissue in a manner resembling normal eruption.

• Korean Journal of Health Education and Promotion
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• v.14 no.1
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• pp.147-160
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• 1997

Nowadays according to the complexity of our daily life due to the development of industry and transportation various kinds of injuries happen. Since 1993 the death rate among 5-14 age children by injuries amount to about 57%. Furthermore, the injury of children can give a direct damage to their own family and it can also bring a serious loss to the country as well as the community where they live in accord with degree of an injury. From this reason, the importance of safety education has been increasing. In this study, it is aimed to clarify the effect of injury preventive behaviors on injury incidence of the 6th grade students in the elementary school. This study is accomplished by the survey sampled from 9 elementary schools in seoul, each of which belong to different district. The survey took for 15 days from the date of september 10th 1996 to september 25th 1996 and the results were as follows; 1. For demographic characteristic, sexual distribution was 48.7% of male students and 47.1% of female students. The required time from home to school was 10-19 minutes(51.8%), and the most way of their going to school is to walk(89.7%). Mothers who graduated from high school were 46.6% and 49.4% of fathers were above university graduated level. The most vocation of mothers was housewife as 56.7%. 2. The results of analysis on the injury rates, 75.8% of children experienced more than one injury and the most was play injury. With regards to sites where injuries happened, the room, the kitchen, and the living room in the house ranked first(38.3%) and then injuries at school such as on the playground, in the classroom, and on the stairs was 34.1%. 3. Considering the rate of injury incidence in accordance with demographic characteristics, male students experienced more injuries than female students(p〈0.05). For the way from home to school, children who went to school by bicycle experienced the most injuries and then on foot, by bus in order of which differences were statistically significant(p〈0.05). 4. From the comparison of parents' safety education practice and the injury incidence, the less often parents practice safety education, the more often children experience injuries(p〈0.05). 5. The results of analysis on the effect of injury preventive behaviors on accidents children who didn't act injury preventive behaviors experienced much more injuries than those who did injury preventive behaviors of which differences were statistically significant(p〈0.01). 6. From the results of analysis of factors effecting on the elementary school children's injuries, children without injury preventive behaviors had more effect on accidents than those who had injury preventive behaviors as odds ratio 2.06(p〈0.01), and the odds ratio of male students compared with female students was 1.47(p〈0.05).