• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.137-141
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• 2005

Though many insecticides are commercially available, development of resistance, pest resurgence and effects on non-target organisms led to the search for alternate insect pest management (IPM) strategy based on larval growth and reproductive fitness. Reproductive potential of insects depends on its acquiring of vitellogenic competence which is under hormonal control. Exogenous application of analogues of JR (JHAs) and ecdysterone could derail normal development and reproduction in insects by manipulating an array of physiological processes. In the rice pest, brown planthopper, Nilaparvata lugens, JHA, hydroprene induced metathetely from the fifth (final) instar nymphs in an age-dependent manner. Day 0 of the final instar showed highest sensitivity to induce this abnormal development. Adults emerged from treated day 3 nymphs looked normal. Both the morphotypes were reproductively incompetent and showed partial to complete sterility. Pre-adult exposure of the ovarian tissue to hydroprene suppressed mitotic division of germinal cells and induced abnormalities in the later s1ages of growth and differentiation of ovary in N. lugens. More over the nymphal exposure to hydroprene inhibited patency changes of follicular epithelium and affected competence of the follicles for yolk sequestration. In the absence of ovarian growth and oocyte differentiation, germarium found disintegrated, trophic core regressed and terminal oocytes resorbed. Hydroprene exposure to newly ecdysed brachypterous females did not affect ovarian development and egg production. Proper larval-adult transition appeared as a. prerequisite for vitellogenic competence in N. lugens for which the ovarian tissues must be exposed to ecdysterone in the internal milieu devoid of JH.

• Journal of Haehwa Medicine
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• v.8 no.1
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• pp.115-129
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• 1999

To evaluate radioprotective effects of Kamisagoonjatang(KST), Kamijihwangtang (KJT) and Kamigoonjajihwangtang(KKJT), studies were done experimentally. The results were obtained as follows: 1. By FACS analysis after exposure to radiation by Liniac, T cell and T-helper cell were significantly increased in KST treated group and also B cell and macrophage in KJT treated group while splenocytes were significantly decreased in control group. 2. WBC, PLT were significantly increased in KKJT treated group as compared with control group after exposure to radiation by Liniac. 3. In histological changes of jejunum of $BALB{\backslash}C$ mice after after exposure to radiation by Liniac, exclusion and fusion of villi were decreased in all groups as compared with control group. 4. In the observation of morphological changes by SEM and TEM after radiation by Liniac, KKJT, KJT and KST inhibited demage of internal structures such as mitochondria, ESR and golgi of jejunum cells in order as compared with control group. From above results it was concluded that KJT, KST and KKJT could be usefully applied for protection from damage by radiotherapy to cancer.

• Nuclear Engineering and Technology
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• v.17 no.4
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• pp.267-278
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• 1985

Some kinds of methods have been applied to regulate the exposure doses by the radioactive effluents from nuclear power plants. The essential one is primary dose equivalent limit recommended by the ICRP. When the primary limit cannot be applied directly for regulation, there have been dose equivalent index in case of external exposure, or maximum permissible concentration, annual limit on intake, derived air concentration and maximum permissible body burden in case of internal exposure. But the derived limit is required from the viewpoint of discharge, for those values are inadequate to control discharge rate directly. This study was carried out to derive the release limit for the Wolsung nuclear power plant by the concentration factor method. This method is based on the assumption of steady state transfer between environment compartments.

• Advances in concrete construction
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• v.11 no.1
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• pp.11-18
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• 2021

The present study fabricated polyvinyl alcohol (PVA) fiber-reinforced alkali-activated slag/fly ash (AASF) composites with varying mixture ratios of slag and fly ash. The thermomechanical behaviors of the AASF composites exposed to 200, 400, 600, or 800℃ were evaluated by means of compressive strength test, visual observation, and fire resistance tests. X-ray diffractometry, mercury intrusion porosimetry, and thermogravimetry tests were performed to analyze the microstructure change of the AASF composites upon exposure to high temperatures. Specimens exhibited a gradual strength loss up to 600℃, while also showing a significant decrease in the strength above 600℃. The fire resistance test revealed the occurrence of an inflection point as indicated by an increase in the internal temperature at around 200℃. In addition, specimens showed the dehydration of C-S-H gel, the presence of åkermanite, gehlenite, and anorthite upon exposure to 800℃, which is associated with the formation of macropore population with pores having diameters of 1-3 ㎛ and 20-40 ㎛. Visual observation indicated that the PVA fibers mitigated the cracking and/or spalling of the specimens upon exposure to 800℃.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.351-356
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• 2021

Korean nuclear power plants (NPPs) have various radiation protection programs to attain radiation exposure as low as reasonably achievable (ALARA). In terms of ALARA, this paper provides a comprehensive overview of administrative dose control for occupationally-exposed workers in Korean NPPs. In addition to dose limits, administrative dose constraints are implemented to resolve an inequity of radiation exposure in which some individuals in NPPs receive relatively higher doses than others. Occupational dose constraints in Korean NPPs are presented in this paper with the background of how those values were determined. For pressurized water reactors, 80% and 90% of the annual average limit for an effective dose, 20 mSv/y, are set as the primary and secondary dose constraints, respectively. Pressurized heavy water reactors (PHWRs) have also established the primary and secondary dose constraints corresponding to 70% and 80% of the effective dose limit, and additional constraints for tritium concentration are provided to control internal exposure in PHWRs. Follow-up measures for exceeding these administrative dose constraints are also introduced compared to exceeding the dose limits. Finally, analysis results of dose distributions show how the implementation of administrative dose constraints impacted the occupational dose distributions in Korean NPPs during the years 2009-2018.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.78-86
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• 2023

Here, upon acute (96 h) and chronic (14 days) exposure, ingestion of polystyrene NPs (100 nm) and physiological, biochemical, and cholinergic modulations were analyzed in the water flea Moina macrocopa exposed to different concentrations (0.001, 0.01, 0.1, 1, 5, 10, 50, 100, and 500 ㎍ l^-1). Exposed NPs were observed in the internal organs (e.g., digestive tract and foregut) of the water flea. Chronic exposure to the relatively high concentrations resulted in significant decreases in survival, body length, and the total number of molts, whereas reproduction parameter was not affected. Significant increase in oxidative stress biomarker (malondialdehyde) and decrease in the intracellular content of endogenous antioxidant (glutathione) and enzymatic activity of antioxidant enzymes (glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase, and glutathione S-transferase) were detected in response to relatively high concentrations of NPs. Transcriptional expression of the hsp70 gene was increased in response to relatively high concentrations of NPs, whereas acetylcholinesterase activity was lowered by the same concentrations of NPs. Taken together, NPs exposure would be a significant modulator on physiological and biochemical metabolism of water flea.

• Tuberculosis and Respiratory Diseases
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• v.87 no.4
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• pp.451-457
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• 2024

Nontuberculous mycobacterial pulmonary disease (NTM-PD) results from the exposure of susceptible hosts to a diverse group of environmental mycobacteria. The emphasis on nonpharmacological strategies is motivated by the widespread presence of NTM in various environments, and the inconsistent success rates of pharmacological treatments. Modifiable factors contributing to NTM-PD development include impaired airway clearance, low body mass index, gastroesophageal reflux disease, and exposure to NTM habitats. This suggests that lifestyle and environmental modifications could affect disease development and progression. The review highlights several modalities that can modify the risk factors. Airway clearance techniques, informed by the "gel-on-brush" model of the bronchial epithelium, aim to enhance mucociliary clearance, and have the potential to alleviate symptoms and improve lung function. The impact of nutritional status is also examined, with a lower body mass index linked to an increased risk and progression of NTM-PD, indicating the importance of targeted nutritional support. Additionally, the theoretical and epidemiological links between gastroesophageal reflux disease and NTM-PD advocate careful management of reflux episodes. Understanding the risk of NTM transmission through environmental exposure to contaminated water and soil is also crucial. Strategies to mitigate this risk, including effective water management and minimizing soil contact, are presented as vital preventive measures. The review supports the inclusion of nonpharmacological treatments within a comprehensive NTM-PD management strategy, alongside conventional pharmacological therapies. This integrated approach seeks to improve the overall understanding and handling of NTM-PD.

• The Journal of Internal Korean Medicine
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• v.43 no.2
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• pp.159-165
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• 2022

Objective: This clinical study describes the effect of Korean medicine on a patient with Delayed Neuropsychiatric Sequelae after Carbon Monoxide Poisoning. Case presentation: A patient with the delayed neuropsychiatric effects of carbon monoxide exposure was treated with herbal medicine, acupuncture, moxibustion, and cupping. Clinical symptoms were measured with the Korean Mini Mental State Examination (K-MMSE), Functional Independence Measure (FIM), and the Modified Barthel Index (MBI). After 32 days of treatment, the patient's K-MMSE score increased from 11 to 21 points, the FIM score from 52 to 94 points, and the MBI score from 46 to 84 points. There were no side effects. Conclusion: According to this case study, Korean medicine may be considered an effective treatment for delayed neuropsychiatric sequelae, although more studies are needed to confirm its validity.

• The Journal of Internal Korean Medicine
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• v.43 no.4
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• pp.503-513
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• 2022

Objectives: The antitussive, expectorant, and anti-inflammatory effects of Mahwangyounpae-tang (MHYPT) aqueous extracts were observed in appropriate animal models of various respiratory disorders. Methods: MHYPT aqueous extracts were orally administered once a day for 11 days at dose levels of 400, 200, and 100 mg/kg. The effect of MHYPT was determined by comparing its antitussive effect with theobromine (TB), its expectorant effect with ambroxol (AM), and its anti-inflammatory effect with dexamethasone (DEXA). Results: MHYPT aqueous extracts (400 mg/kg) showed favorable antitussive effects comparable to those of TB (50 mg/kg) in the NH₄OH-exposure coughing mouse model and expectorant effects comparable to those of AM (250 mg/kg) in the phenol red-secretion mouse model, but MHYPT (400 mg/kg) showed less anti-inflammatory activity compared to DEXA (1 mg/kg) in the xylene-induced acute inflammatory mouse ear model under the experimental conditions used. Conclusion: MHYPT aqueous extracts administered at dosage levels of 400, 200, and 100 mg/kg induced dose-dependent and favorable antitussive, expectorant, and anti-inflammatory activities that occurred by simultaneous modulation of the activity of mast cells and respiratory mucous production under the experimental conditions used in this study.

• Journal of Veterinary Science
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• v.23 no.6
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• pp.83.1-83.7
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• 2022

Severe fever with thrombocytopenia syndrome (SFTS) is a zoonotic disease, and its clinical information and prevalence are important. This study was conducted on 22 feline patients from the Republic of Korea (ROK), suspected to suffer from a tick-borne disease. Four cats were positive for SFTS, and genotypes B-1, B-3, D, and F were identified. Clinical symptoms, such as anorexia, jaundice, thrombocytopenia, leukopenia, and hyperbilirubinemia, were detected. This is the first report of SFTS virus genotypes B-1, D, and F from cats in the ROK. Moreover, our results suggest that jaundice may be an indicator of SFTS in cats.