• 제목/요약/키워드: Biological deterioration

검색결과 166건 처리시간 0.023초

SWMM을 이용한 도시화유역 불투수율 변화에 따른 강우유출특성 분석 (Analysis of Rainfall-Runoff Characteristics on Impervious Cover Changes using SWMM in an Urbanized Watershed)

  • 오동근;정세웅;류인구;강문성
    • 한국물환경학회지
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    • 제26권1호
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    • pp.61-70
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    • 2010
  • The increase of impervious cover (IC) in a watershed is known as an important factor causing alteration of water cycle, deterioration of water quality and biological communities of urban streams. The study objective was to assess the impact of IC changes on the surface runoff characteristics of Kap Stream basin located in Geum river basin (Korea) using the Storm Water Management Model (SWMM). SWMM was calibrated and verified using the flow data observed at outlet of the watershed with 8 days interval in 2007 and 2008. According to the analysis of Landsat satellite imagery data every 5 years from 1975 to 2000, the IC of the watershed has linearly increased from 4.9% to 10.5% during last 25 years. The validated model was applied to simulate the runoff flow rates from the watershed with different IC rates every five years using the climate forcing data of 2007 and 2008. The simulation results indicated that the increase of IC area in the watershed has resulted in the increase of peak runoff and reduction of travel time during flood events. The flood flow ($Q_{95}$) and normal flow ($Q_{180}$) rates of Kap Stream increased with the IC rate. However, the low flow ($Q_{275}$) and drought flow ($Q_{355}$) rates showed no significant difference. Thus the subsurface flow simulation algorithm of the model needs to be revisited for better assessment of the impact of impervious cover on the long-term runoff process.

중요민속자료(복식)의 보존처리 (The Conservation Treatment for the Important Folklore Materials-Clothes)

  • 한성희;이규식
    • 보존과학연구
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    • 통권14호
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    • pp.94-108
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    • 1993
  • The cultural properties of cloth are of animal orgin (silk), or of vegetable orgin(cotton, hemp, ramie). As clothes are of an orginic material, they were subjected to damage by chemical, phisigical or biological factors, viz, moulds insects, lights, humidity and temperature changes, etc. And these factors promote that clothes generally result from various types of deterioration. In 1992, We were performed the conservation treatments for total 9 pieces of cloth, such as 3 pieces of General PAK SHIN-RYONG(Important Folklore Material No.110) 3 pieces of Madam Jung(Important Folklore Material No.115) and 1 piece of King Se-jo(Important Folklore Material No.219). The procedure of the conservation treatment for clothes describe the following below. 1) The washing and dry-cleaning to remove the contaminated substances from cloth was used 0.2% stearyl potassium soap solution and the mixture solution compound of n-Hexane, C6H14. and n-Decane, C10H22. And after the washing and dry-cleaning, the dry of clothes was carried out in a warm condition. These steps were repeated in 2 times over for each cloth. 2) The repair of clothes was attached the similar textiles to stronger fabric linings by needlework.3) The reprodution was made for cloth of King Se-jo to equalize the type, color, quality and skill of materials. 4) After these above procedures, all clothes fumigated to prevent the biodeterioration by using the mixed gas of methyl bromide and ethylene oxide as insecticide and fungicide. 5) Finally for the purpose to keep in a safety long-term condition, the treated clothes sealed with Biaxially Oriented Polyvinylacohol Film(BO-PVA film) and Helium, purity 99.999%, filled up in sealed BO-PVA film bag.

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이 충무공 관련 고문헌에 대한 보존처리 (Conservation Treatment of the Historical Paper Documents Related to Chungmugong Yi, Sunsin)

  • 박소현;신효영;홍순천;조안나;박지희
    • 보존과학연구
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    • 통권33호
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    • pp.19-32
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    • 2012
  • 천연재료를 사용하는 지류유물의 손상은 재질적 특성상 어떤 한 가지 요인에 의한 훼손보다는 물리적, 화학적, 생물학적 복합요인에 의한 손상 가능성이 높다. 문화재보존과학센터는 2009년 12월 현충사 관리소로 부터 이 충무공관련 유물의 상태조사 및 보존처리를 의뢰받아 조사한 결과 위와 같은 다양한 훼손요인을 확인할 수 있었다. 조사결과를 토대로 각 유물의 손상정도를 파악한 후 적절한 보존방안을 수립하고, 2010년부터 약 2년에 걸쳐 보존처리를 실시하였다. 이 충무공 관련 유물 중 고문서, 전적류 등과 같이 형태가 다른 고문헌에 대한 손상유형과 보존처리 내용을 소개함으로서 보존처리방법을 선택하는 하나의 예시를 제안하고자 하였다. 지류유물에 대한 보존처리는 유물의 노화주기를 연장시키고 2차 손상을 방지하지만, 유물의 노화를 완전히 멈추게 하는 과정이 아니므로 유물에 대한 정기적 점검이 필요할 것이다.

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TNF-α-Induced SOX5 Upregulation Is Involved in the Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells Through KLF4 Signal Pathway

  • Xu, Lijun;Zheng, Lili;Wang, Zhifang;Li, Chong;Li, Shan;Xia, Xuedi;Zhang, Pengyan;Li, Li;Zhang, Lixia
    • Molecules and Cells
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    • 제41권6호
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    • pp.575-581
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    • 2018
  • Postmenopausal osteoporosis (PMOP) is a common systemic skeletal disease characterized by reduced bone mass and microarchitecture deterioration. Although differentially expressed SOX5 has been found in bone marrow from ovariectomized mice, its role in osteogenic differentiation in human mesenchymal stem cells (hMSCs) from bone marrow in PMOP remains unknown. In this study, we investigated the biological function of SOX5 and explore its molecular mechanism in hMSCs from patients with PMOP. Our findings showed that the mRNA and protein expression levels of SOX5 were upregulated in hMSCs isolated from bone marrow samples of PMOP patients. We also found that SOX5 overexpression decreased the alkaline phosphatase (ALP) activity and the gene expression of osteoblast markers including Collagen I, Runx2 and Osterix, which were increased by SOX5 knockdown using RNA interference. Furthermore, $TNF-{\alpha}$ notably upregulated the SOX5 mRNA expression level, and SOX5 knockdown reversed the effect of $TNF-{\alpha}$ on osteogenic differentiation of hMSCs. In addition, SOX5 overexpression increased Kruppel-like factor 4 (KLF4) gene expression, which was decreased by SOX5 silencing. KLF4 knockdown abrogated the suppressive effect of SOX5 overexpression on osteogenic differentiation of hMSCs. Taken together, our results indicated that $TNF-{\alpha}$-induced SOX5 upregulation inhibited osteogenic differentiation of hMSCs through KLF4 signal pathway, suggesting that SOX5 might be a novel therapeutic target for PMOP treatment.

유한 요소법을 이용한 나이에 따른 척추의 형상 및 구조변화의 효과 (Age-related Geometric Effects on the Human Lumbar Spine by the Finite Element Method)

  • 김용
    • 대한의용생체공학회:의공학회지
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    • 제21권3호
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    • pp.285-293
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    • 2000
  • 나이에 의한 외부의 환경조건의 변화는 이에 적응하려는 척추의 구조적인 변화를 가져온다. 이러한 구조적인 변화는 척추의 biomechanical 거동에 영향을 미칠 것이다. 이러한 구조적인 변화의 효과를 연구하기 위하여, 나이에 의한 척추의 재료 및 기계적인 물성의 변화는 제외되었다. 유한요소법 (finite element method)에 의한 lumbar spine model (L3-L4)에 있어서, Annulus 의 유한요소 모델은 laminate composite elements로서 16개의 layer와 6개의 물성으로 구성되어있다. Spinal stiffness 와 facet reaction은 나이가 들수록 증가했다. 나이가 들수록 inner annulus의 fiber/layer tensile strains, cancellous bone stress 및 end-Plate stress는 감소했다. Fiber/layer compressive strains, facet reaction, ligament reaction and end-plate rigidity는 나이에 의한 척추의 구조적인 변화에 의하여 증가했다. 따라서 나이에 의한 척추의 정상적인 쇠퇴과정에 있어서 척추의 구조적인 변화는 spinal stiffness를 증가 시켜서 척추 및 disc의 지나친 변형을 감소시킬 것이다.

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Influence of Temperature and Water Activity on Deleterious Fungi and Mycotoxin Production during Grain Storage

  • Mannaa, Mohamed;Kim, Ki Deok
    • Mycobiology
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    • 제45권4호
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    • pp.240-254
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    • 2017
  • Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

근적외선 분광법 기반 비침습식 혈당 검출 센서 시스템 (Non-invasive Blood Glucose Detection Sensor System Based on Near-Infrared Spectroscopy)

  • 강영만;한순희
    • 한국전자통신학회논문지
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    • 제16권5호
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    • pp.991-1000
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    • 2021
  • 비침습식 혈당 검출 기술 중 광학 기법은 생물학적 매체를 통과할 때 빛의 반사와 흡수 및 산란 특성을 이용하는 방법으로 통증이나 측정의 불편함을 감소시키고 감염 위험이 없어 혈당 검출 연구의 주요 흐름이 되고 있다. 이 중 근적외선 분광법은 혈당 분자와 유사한 흡수 기능을 공유하는 단백질과 산의 간섭들로 감지된 신호 분석 시 복잡성이 증가하는 단점이 있다. 본 연구에서는 근적외선의 피부 흡수로 발생할 수 있는 혈당검출 기능저하를 완화시키기 위해 다중 근적외선 대역의 비침습식 센서시스템을 설계하고 제작하였다. 제작한 시스템의 검증을 위해 혈액 조사를 실시하였으며, 혈액 내의 혈당 반응 정도를 스펙트럼 데이터로 수집하고, 데이터와 혈당과의 상관관계 관점에서 정량적으로 본 연구의 성과를 검증하였다.

원주천 수질개선 방안 및 개선효과 평가 (An Analysis of the Water Quality Improvement Measures and Evaluation of Wonju Stream)

  • 금동혁;신민환;유나영;이서로;김동진;성윤수;이상수
    • 한국농공학회논문집
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    • 제63권1호
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    • pp.61-73
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    • 2021
  • Recently, the deterioration of water quality in Wonju stream has been reported due to the increase in diverse pollution sources along with community development and urbanization. Various types of attempts with a huge budget were made for better water quality so far, but its effectiveness is still doubted. In order to establish site-oriented measures for water quality improvement, the topographic and hydrologic factors were evaluated based on site inspection and survey. As the major streams merged into the Wonju stream, the Hwa and Heungyang streams were found to have higher pollution loads and contributions compared to other streams due to the scattered livestock farms and industries, and vulnerable land use. Notably, the discharge water from the Wonju Public Sewage Treatment Plant had the highest level of pollution load, impacting on the water quality of Wonju Stream. According to the SWAT model as water quality measures, the improvement effect of water quality in this treatment plant can be reached to the reductions in BOD 11.06%, T-N 23.56%, T-P 10.60% when the proper managements applied, whereas the improvement of water quality would be 3.89%, 1.23%, and 3.32% for BOD, T-N, T-P, respectively, for the industries. The reduction of the livestock industry was generally very high as a pollution source, but it was not much higher at the end of Wonju Stream than other measures. These results recommended that the water q uality improvement measures should be designated for each upper-middle-lower section in Wonju stream.

Application of Edible Insects as Novel Protein Sources and Strategies for Improving Their Processing

  • Kim, Tae-Kyung;Cha, Ji Yoon;Yong, Hae In;Jang, Hae Won;Jung, Samooel;Choi, Yun-Sang
    • 한국축산식품학회지
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    • 제42권3호
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    • pp.372-388
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    • 2022
  • Insects have long been consumed by humans as a supplemental protein source, and interest in entomophagy has rapidly increased in recent years as a potential sustainable resource in the face of environmental challenges and global food shortages. However, food neophobia inhibits the widespread consumption of edible insects, despite their high nutritional and functional value. The own characteristics of edible insect protein such as foaming properties, emulsifying properties, gelling properties and essential amino acid ratio can be improved by drying, defatting, and extraction. Although nutritional value of some protein-enriched bread, pasta, and meat products, especially essential amino acid components was increased, replacement of conventional food with edible insects as a novel food source has been hindered owing to the poor cross-linking properties of edible insect protein. This deterioration in physicochemical properties may further limit the applicability of edible insects as food. Therefore, strategies must be developed to improve the quality of edible insect enriched food with physical, chemical, and biological methods. It was presented that an overview of the recent advancements in these approaches and highlight the challenges and prospects for this field. Applying these strategies to develop insect food in a more familiar form can help to make insect-enriched foods more appealing to consumers, facilitating their widespread consumption as a sustainable and nutritious protein source.

A positive feedback loop of heparanase/syndecan1/nerve growth factor regulates cancer pain progression

  • Xiaohu Su;Bingwu Wang;Zhaoyun Zhou;Zixian Li;Song Tong;Simin Chen;Nan Zhang;Su Liu;Maoyin Zhang
    • The Korean Journal of Pain
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    • 제36권1호
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    • pp.60-71
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    • 2023
  • Background: The purpose of this research was to assess the role of heparanase (HPSE)/syndecan1 (SDC1)/nerve growth factor (NGF) on cancer pain from melanoma. Methods: The influence of HPSE on the biological function of melanoma cells and cancer pain in a mouse model was evaluated. Immunohistochemical staining was used to analyze HPSE and SDC1. HPSE, NGF, and SDC1 were detected using western blot. Inflammatory factors were detected using ELISA assay. Results: HPSE promoted melanoma cell viability, proliferation, migration, invasion, and tumor growth, as well as cancer pain, while SST0001 treatment reversed the promoting effect of HPSE. HPSE up-regulated NGF, and NGF feedback promoted HPSE. High expression of NGF reversed the inhibitory effect of HPSE down-regulation on melanoma cell phenotype deterioration, including cell viability, proliferation, migration, and invasion. SST0001 down-regulated SDC1 expression. SDC1 reversed the inhibitory effect of SST0001 on cancer pain. Conclusions: The results showed that HPSE promoted melanoma development and cancer pain by interacting with NGF/SDC1. It provides new insights to better understand the role of HPSE in melanoma and also provides a new direction for cancer pain treatment.