• 공업화학
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• 제22권6호
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• pp.636-641
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• 2011

1990년대 중반부터 지속적으로 산불건수가 증가하고 있으며, 그 규모 또한 대형화 되고 있다. 하지만 이러한 산불의 대형화 추세에도 낙엽, 초본류, 침엽수 및 활엽수에 따른 국 내외에는 수종별 열분해 및 연소 특성에 관한 연구가 미미한 실정이다. 본 논문에서는 국내 산림의 대표적인 침엽수인 적송의 생목과 간벌목을 대상으로 TGA를 이용 열분해 및 연소 특성에 대한 연구를 수행하였다. 적송 생목의 경우 $200^{\circ}C$ 부근에서 발화되고 열분해는 $230^{\circ}C$에서부터 시작되었다. 적송 간벌목의 경우는 발화온도와 열분해 온도가 각각 180와 $205^{\circ}C$부근에서 시작되었다. TGA 분석으로 얻은 실험데이터로부터 열분해반응에서 활성화에너지는 전화율 증가에 따라 증가하였다. 그러나 연소반응에서의 활성화에너지는 감소하는 경향을 나타냈다.

• 한국폐기물자원순환학회지
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• 제35권8호
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• pp.692-700
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• 2018

In this study, the results of PBDEs and HBCDs of the products and waste that contain BFRs such as domestic electronic products, automobiles and textile products were compared with international management standards, and their excess rates were calculated. Deca-BDE was detected among the PBDEs in TV rear cover plastics, car seats, automotive interior plastics, and automobile shredding residues of products and waste containing BFRs. The comparison with Basel Convention management standards (1,000 mg/kg) for PBDE-containing wastes (4 types in total) shows that the excess rate of all samples was less than 1.5%. The estimated excess rate compared to the EU and Basel convention management standards (1,000 mg/kg) for PBDEs (4 species + deca-BDE) and TV rear cover plastics was 37.5% (30 of 80 samples exceeded the standards). The estimated excess rate compared to the Basel convention management standards (1,000 mg/kg) for HBCD, building materials products and waste was 15.7% (17 of 108 samples exceeded the standards). In the case of PBDEs, it is necessary to remove only the rear cover of CRT TV among the electric and electronic products and treat it in the flame retardant treatment facility to improve the recycling collection system. In the case of HBCD, it is necessary to appropriately dispose of the recycled materials, heat insulation materials, TV plastics, and styrofoam in marine fishery among construction materials and restrict the use as recycled raw materials.

• Journal of Forest and Environmental Science
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• 제38권2호
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• pp.128-132
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• 2022

Wild boars (Sus scrofa) not only cause crop damage and human casualties, but also facilitate the spread of many infectious diseases in domestic animals and humans. To determine the efficiency of a fencing system in blocking the movement of wild boars, long-term monitoring was performed in a fenced area in Bukhansan National Park using camera traps. Upon monitoring for a period of 46 months, there was a 72.6% reduction in the number of wild boar appearances in the fence-enclosed area, compared to that in the unenclosed area. For 20 months after the fence installation, the blocking effect of the fence was effective enough to reduce the appearance of wild boars by 92.6% in the fence-enclosed area, compared to that in the unenclosed area. The blocking effect of the fence remained effective for 20 months after its installation, after which its effectiveness decreased. Maintaining a fence for a long time is likely to lead to habitat fragmentation. It can also block the movement of other wild animals, including the endangered species - the long-tailed goral. This study suggests a 20-month retention period for the fences installed to inhibit the movement of wild boars in wide forests such as Gangwon-do in South Korea. To identify how long the blocking effect of the fences lasts, further studies are needed focusing on the length and height of the fence, and the conditions of the ground surface.

• 대한본초학회지
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• 제34권3호
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• pp.9-17
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• 2019

Objectives : This study was performed to compare the effect of two Cudrania tricuspidata cultivars; Sancheong native (CT) and varieties in china(SCT) on immediate hypersensitivity of the anaphylactic type and Ova-induced allergic asthma mouse model by calculating serum cytokines and IgE. Methods : We investigated the free radical scavanging effect and quantify total phenol contents and total flavonoids of two Cudrania tricuspidata cultivars; Sancheong native(CT) and varieties in china(SCT). The sample was extracted by 80% EtOH. To induce the allergic asthma, in the control group and the CT group, mice of each group were sensitized intraperitoneally with ovalbumin (OVA) solution at the 1st, the 7th and the 14th day. After then, sensitization was performed by aerosol allergen challenges with 1% OVA solution intratracheally at the 21th, the 23th, 25th and the 27th day. At the 29th day, the mice were killed and the changes of interferon-${\gamma}$, interleukin-4, 5 and 10, total IgE and OVA-specific IgE in serum were checked. Results : CT inhibited compound 48/80-induced systemic anaphylaxis 90% with a dose of 100 mg/kg body weight at 1 hr before injection of compound 48/80. In the allergic asthma mouse model, IFN-${\gamma}$ was did not increased in the CT and SCT group than that in the control group. IL-4, IL-5, the total IgE and OVA-specific IgE were decreased in the CT group as compared with the control group and these results were statistically significant. Conclusions : Considering the above experimental results, this study showed that Sancheong native cultivar could reduce the allergic reaction.

• Journal of the Korean Wood Science and Technology
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• 제30권1호
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• pp.40-47
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• 2002

PEG처리에 의한 국내산 주요 소경재 다섯 수종(소나무, 잣나무, 일본잎갈나무, 신갈나무, 굴참나무)의 치수안정성을 조사하고, 목재내의 PEG분포를 X선회절법에 의해 검토하였다. 그 결과 공시수종 모두 PEG 30%의 수용액에서 좋은 치수안정 효과를 보여 주었다. 또한 PEG농도 증가에 따라 PEG처리 목재의 중량증가율과 벌킹효과가 증가하였는데 침엽수재가 활엽수재에 비해 그 정도가 크게 나타났다. X선회절 결과, 잣나무는 만재와 조재 모두 2𝜃 = 19°와 2𝜃 = 23° 부근에서 PEG결정유래의 피크가 나타나지 않았다. 이러한 X선회절 결과는 잣나무재내에 신갈나무재보다 더 많은 양의 PEG가 존재하는 것을 의미하는 것으로서 치수안정성이 큰 이유를 설명해 주는 증거의 하나로 생각되었다.

• 농촌의학ㆍ지역보건
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• 제47권2호
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• pp.61-66
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• 2022

Objectives: In the epidemiology of communicable diseases, the term epidemic period, also referred to as "wave" is often used in the general and academic milieu. A wave refers to a natural pattern of increase in the number of sick individuals, a defined peak, and then a decline in the number of cases. It implies a pattern of peaks and valleys after a particular peak is taken. The idea of epidemic waves is a useful tool for predicting the course as well as helping to accurately describe an epidemic. However, in many domestic and foreign news as well as in various research results in Korea, most of the reports either had no standard, were inaccurate, had a questionable classification of the period of the epidemic, or the basis for classification of a given wave was not presented. Methods: The author reviewed and organized related literature with epidemic wave. The author made several suggestions of an epidemic wave as follows. Results: To start with, it should be based on the number of incident cases in consideration of the size of the outbreak, then the period from the bottom to the peak and then reaching the next bottom; also, the period over a certain scale based on the number of incident cases; and the period according to the change in the major infection type (mutation-dominant species). In addition, according to the period of change in the vaccination rate (formation of herd immunity), as well as the content and duration of the intervention, that is, classification according to the applied quarantine stage. Furthermore, the classification of epidemic periods by the time-dependent reproduction number or time-varying reproduction number (Rt), and lastly the application of mathematical methodology. Conclusions: Therefore, classifying the epidemic period into generally known and accepted time frames is considered to be a very important task for future research analysis and development of intervention strategies.

• Journal of Plant Biotechnology
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• 제49권4호
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• pp.325-330
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• 2022

본 연구는 국내에서 소비되는 약용작물 중 경제적 가치는 높으나 국내 생산량이 적고 수입 의존도가 높은 Atractylodes의 식물 조직 배양 시스템을 구축하기 위해 수행되었다. 삽주는 A. ovata를 사용하였고, 4가지 cytokinins류, 6-benzylaminopurine (BA), zeatin, kinetin, thidiazuron (TDZ)을 2가지 농도(0.5, 1.0 mg/L)로 처리하였다. 4가지 유형의 cytokinin 중 BA처리는 A. ovata의 신초유도와 뿌리 생육에 효과적이었다. 0.5 mg/L 및 1.0 mg/L BA 모두 BA 처리에서 유사한 결과를 나타내었지만 1.0 mg/L BA가 신초와 뿌리 생육을 촉진하는데 더 효과적이었다. 처리 중 신초의 개수와 뿌리의 생중량(FW)을 제외하고는 TDZ 처리가 신초와 뿌리생육에 효과적이지 않아 본 수종에서는 적합하지 않았다. 본 연구에서는 A. ovata의 아배양을 이용한 기내증식 시스템을 구축하였다. 위 결과는 기내 재분화를 이용한 산림약용자원 A. ovata의 안정적인 생산 및 증식을 위한 기반 기술로 사용될 것으로 사료된다.

• Journal of the Korean Wood Science and Technology
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• 제51권5호
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• pp.410-418
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• 2023

In this study, the combustion characteristics of the Tulip tree, which is the representative broad-leaved afforestation tree in Korea, were analyzed. The flame retardant performance of the Tulip tree was analyzed by analyzing combustion characteristics on a total of three test samples; flame retardant treated, both flame retardant and oil stain-treated, and untreated. Then the flame retardance grade was classified for each of them. According to the result, test samples showed the strongest flame retardance were in order of flame retardant treated (C), both flame retardant and oil stain-treated (B), and untreated (A). As a result of analyzing the total heat emission and maximum heat emission rates, which is the evaluation standard for interior materials of Korean domestic buildings, test samples with flame retardant treat or flame retardant and oil stain treat were qualified for the flame-retardant standard. Both flame retardant and oil stain-treated samples showed higher total heat release (THR) and heat release rate compared to flame retardant-treated samples as the oil causes combustion with oxygen. On the other hand, they didn't qualify the THR in Quasi-non-combustible standards. To determine the correlation between the physical and combustion characteristics of wood, the combustion characteristics of other diffuse porous wood species, with which the Tulip tree is affiliated were analyzed, and noticed that the characteristic correlates with the density and quantity of wood. The results of this study are expected to be used as basic information on the combustion characteristics of the Tulip tree.

• Journal of Veterinary Science
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• 제23권1호
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• pp.3.1-3.12
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• 2022

Background: Domestic yaks are the most important livestock species on the Qinghai-Tibetan Plateau. Adult female yaks normally breed in the warm season (July to September) and enter anestrous in the cold season (November to April). Nevertheless, it is unclear how ovarian activity is regulated at the molecular level. Objectives: The peculiarities of yak reproduction were assessed to explore the molecular mechanism of postpartum anestrus ovaries in yaks after pregnancy and parturition. Methods: Sixty female yaks with calves were observed under natural grazing in Haiyan County, Qinghai Province. Three yak ovaries in pregnancy and postpartum anestrus were collected. RNA sequencing and quantitative proteomics were employed to analyze the pregnancy and postpartum ovaries after hypothermia to identify the genes and proteins related to the postpartum ovarian cycle. Results: The results revealed 841 differentially expressed genes during the postpartum hypoestrus cycle; 347 were up-regulated and 494 genes were down-regulated. Fifty-seven differential proteins were screened: 38 were up-regulated and 19 were down-regulated. The differential genes and proteins were related to the yak reproduction process, rhythm process, progesterone-mediated oocyte maturation, PI3K/AKT signaling pathway, and MAPK signaling pathway categories. Conclusions: Transcriptome and proteomic sequencing approaches were used to investigate postpartum anestrus and pregnancy ovaries in yaks. The results confirmed that BHLHE40, SF1IX1, FBPX1, HSPCA, LHCGR, BMP15, and ET-1R could affect postpartum hypoestrus and control the state of estrus.

• 한국자원식물학회지
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• 제36권4호
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• pp.282-289
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• 2023

본 연구를 통해 국내 감초 신품종인 G. korshinskyi Grig.가 cerulein으로 유도한 생쥐의 급성 췌장염시 증가하는 염증성 세포의 유입과 혈청 소화효소(Amylase, Lipase) 수치를 유의하게 억제함으로써 급성 췌장염에 대한 보호 효과를 나타낸다는 것을 알 수 있었다. 이를 통해 급성 췌장염을 예방할 수 있는 의약품 소재로써 국내 감초 신품종의 가능성을 제기한다는 데 의의가 있지만, 치료 효과로써의 효능 및 억제 기전에 대한 보완연구가 뒷받침되어야 할 필요가 있다고 판단된다.