• Title/Summary/Keyword: damage factor

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Effect of Ghrelin on Memory Impairment in a Rat Model of Vascular Dementia (그렐린이 혈관성 치매 쥐의 기억 손상에 미치는 효과)

  • Park, Jong-Min;Kim, Youn-Jung
    • Journal of Korean Academy of Nursing
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    • v.49 no.3
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    • pp.317-328
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    • 2019
  • Purpose: The purpose of this study was to identify the effect of ghrelin on memory impairment in a rat model of vascular dementia induced by chronic cerebral hypoperfusion. Methods: Randomized controlled groups and the posttest design were used. We established the representative animal model of vascular dementia caused by bilateral common carotid artery occlusion and administered $80{\mu}g/kg$ ghrelin intraperitoneally for 4 weeks. First, behavioral studies were performed to evaluate spatial memory. Second, we used molecular biology techniques to determine whether ghrelin ameliorates the damage to the structure and function of the white matter and hippocampus, which are crucial to learning and memory. Results: Ghrelin improved the spatial memory impairment in the Y-maze and Morris water maze test. In the white matter, demyelination and atrophy of the corpus callosum were significantly decreased in the ghrelin-treated group. In the hippocampus, ghrelin increased the length of hippocampal microvessels and reduced the microvessels pathology. Further, we confirmed angiogenesis enhancement through the fact that ghrelin treatment increased vascular endothelial growth factor (VEGF)-related protein levels, which are the most powerful mediators of angiogenesis in the hippocampus. Conclusion: We found that ghrelin affected the damaged myelin sheaths and microvessels by increasing angiogenesis, which then led to neuroprotection and improved memory function. We suggest that further studies continue to accumulate evidence of the effect of ghrelin. Further, we believe that the development of therapeutic interventions that increase ghrelin may contribute to memory improvement in patients with vascular dementia.

The Direction and Implication of Urban Development in the Age of Response Climate Change (기후변화 대응시대의 도시개발방향과 시사점)

  • Oh, Eun-Yeol
    • Journal of Industrial Convergence
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    • v.17 no.1
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    • pp.33-39
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    • 2019
  • The purpose of this study was to present the direction and implications of urban development in relation to climate risk factors and environment for practical implementation of urban development in response to climate change. The research method was carried out through a qualitative data survey and analysis. As a result of the study, the direction of urban development according to the climate risk factors emphasized the importance of preparing conditions for urban development by establishing a damage prevention system for natural disasters and analyzing the risk of natural disasters by conducting analysis of the impact and vulnerability of climate change in urban planning. The direction of urban development on the environmental side suggested the need for the promotion of public transport oriented development (TOD) in the form of urban planning to realize sustainable and practical urban development. Future research directions will need to be supplemented with more quantitative and empirical findings.

A Development Inspection Management Operation Model of High Pressure Underground Pipeline in Industrial estate (산업단지 고압매설배관의 점검 관리 운영 모델 개발)

  • Choi, Ji-Hun;Kim, Jin-Jun;Rhie, Kwang-Won;Kim, Tae-Hun
    • Journal of the Korean Institute of Gas
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    • v.23 no.1
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    • pp.62-69
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    • 2019
  • The high pressure underground pipelines of industrial states such as Ulsan, Yeosu consist with not only the pipelines for the utility support such as Raw material of petrochemical industry and steam, but also high pressure pipelines of toxic, flammable gas intricately like a web. Therefore, in this study, based on in-depth comparison analysis of industrial estate pipelines, and underground city gas pipelines' safety management status, excavation frequency, excavation depth, patrol period which are pipe damage impact factor by the other construction are analyzed. And, as a result, risk changes and correlations due to risk reduction strategy of the other construction are compared to be presented the safety inspection operation model for the high pressure underground pipelines of industrial estates.

Renoprotective Effect of Maydis Stigma on Puromycin Aminonucleoside-induced Nephrotic Syndrome (Puromycin Aminonucleoside에 의해 유도된 신증후군에 대한 옥미수(玉米鬚)의 보호효과)

  • Yoon, Jung-Joo;Kho, Min-Chol;Han, Byung-Hyuk;Kim, Hye-Yoom;Ahn, You-Mee;Lee, Yun-Jung;Lee, Ho-Sub;Kang, Dae-Gill
    • The Journal of Korean Obstetrics and Gynecology
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    • v.34 no.4
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    • pp.1-11
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    • 2021
  • Objectives: Nephrotic syndrome is a kidney disorder, which is characterized by proteinuria, edema (swelling), and hyperlipidemia. Maydis Stigma (Corn silk) has been widely used in Asia as a traditional medicine and is known to have a diuretic effect and is used for the treatment of edema and indigestion. Methods: The aim of this study is to investigate the improvement effect of Maydis Stigma in treating nephrotic syndrome induced by puromycin aminonucleoside. Sprague-Dawley rats were intravenously injected with 75 mg/kg/day puromycin aminonucleoside, then treated with either Losartan or 200 mg/kg/day Maydis Stigma for seven days. Results: Maydis Stigma significantly decreased ascites and proteinuria level. Plasma levels of blood urea nitrogen (BUN) and plasma creatinine reduced significantly by Maydis Stigma. In addition, treatment with Maydis Stigma attenuated histological damage. Treatment with Maydis Stigma also restored podocin expression and reduced inflammation markers such as intracellular adhesion molecules (ICAM-1), monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor alpha (TNF-α) and high-mobility group box-1 (HMGB1). Conclusions: Maydis Stigma ameliorates kidney injury in nephrotic syndrome rat models. Maydis Stigma exerts a renoprotective effect owing to its anti-inflammatory effects and reductions of ascites and proteinuria. Thus, these results indicate that Maydis Stigma is likely to be a promising agent in the treatment of nephrotic syndrome.

Rapid Structural Safety Evaluation Method of Buildings using Unmanned Aerial Vehicle (SMART SKY EYE) (무인비행체를 이용한 건축물의 긴급 위험도 평가 기술 (SMART SKY EYE) 개발)

  • Jeong, Dong-Min;Lee, Jong-Hoon;Lee, Da-Hye;Ju, Young-Kyu
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.35 no.2
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    • pp.3-11
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    • 2019
  • The recent earthquake of Pohang (M5.4) and the Gyeongju earthquake (M5.8) suggested the possibility of a strong earthquake in Korea and reminded us that the Korea is no longer an earthquake-safe zone. In the disaster recovery stage in a disaster like an earthquake, the investigation of the damage situation and the safety assessment of the building serve to provide important information for the initial action such as establishment of the recovery strategy and rescue of the survivor. However, the research that depends on manpower can not cope with the difficulty of processing a large number of doses in a short time, and the expertise of the manpower must be taken into consideration, which may result in delayed initial action. In this study, we propose an rapid safety evaluation technique of building using unmanned aerial vehicle which evaluates the performance and safety of buildings by integrating conventional safety inspection method with unmanned aerial vehicle technology and developed evaluation method of each evaluation factor. In order to verify this, the buildings damaged by the earthquake in Pohang were checked and compared using this system. The results are consistent with the results of the existing emergency earthquake risk assessment. As a result, the possibility of checking the emergency safety using the unmanned aerial vehicle for the damaged structures in case of a large-scale disaster such as an earthquake was confirmed.

A Study on the Analysis of Positional Accuracy between the GPR Survey Data and Underground Space Integration Map (현장 GPR 탐사자료와 지하공간통합지도 상호위치 정확도 분석에 관한 연구)

  • SONG, Seok-Jin;CHO, Hae-Yong;HAN, Dam-Hye;KIM, Sung-Gil
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.4
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    • pp.208-216
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    • 2020
  • Recently, issues regarding underground safety such as sink hole, ground subsidence and damage to old underground facilities have been increasing in urban areas, raising the need for more accurate management of underground facilities. Thus, this study derived a technique for comparing spatial data of underground facilities acquired from GPR exploration results acquired at the site with spatial data of integrated underground spatial maps. Using this underground space integrated map-linked service prototype program developed through this study, comparing the location information of the GPR exploration results and the underground space integrated map for the verification of site usability in some sections around Gangnam Station, the results demonstrated that the location of the map is 0.879m maximum, minimum of 0.101m and the average fudge factor was 0.625m. If accuracy of the GPR exploration results is guaranteed, it is judged that it can be used to improve the location accuracy of the underground space integration map.

Development of an accelerated life test procedure considering the integrated equivalent load of an implement working pump for an agricultural tractor

  • Moon, Seok-Pyo;Baek, Seung-Min;Chung, Sun-Ok;Park, Young-Jun;Han, Tae-Ho;Kim, Yong-Joo
    • Korean Journal of Agricultural Science
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    • v.47 no.4
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    • pp.1123-1134
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    • 2020
  • The goal of this study was to develop an accelerated life test for an implement working pump for an agricultural tractor. The field experiments were conducted to measure the load of an implement working pump during major agricultural operations such as plow tillage, rotary tillage, baler operations, and wrapping operations. The measurement system for an implement working pump load was constructed using a pressure sensor, the engine rotational speed, and the hitch pump displacement. The measured implement working pump load was calculated as an equivalent load for each agricultural operation using the Palmgren-Miner rule, which is a cumulative damage method. The equivalent load was calculated using the total load data and peak load data when the total data included the operation of an implement working. The annual usage time of the agricultural tractor was applied to develop two integrated equivalent loads. The acceleration factor was calculated to develop an accelerated life test and was calculated from the two integrated equivalent loads, the maximum pressure, and the flow rate conditions of the hitch pump. In Korea, the warranty life of a tractor is 2,736 hours, and the time required for the test to guarantee the operational life of tractors was calculated as 7,561 hours. The acceleration factors were calculated as 453.6 and 38.3, respectively, from the total load data and peak load data. The fatigue test time can be shortened by 16.7 and 197.4 hours according to the result of the acceleration factors.

Potential immune-modulatory effects of wheat phytase on the performance of a mouse macrophage cell line, Raw 264.7, exposed to long-chain inorganic polyphosphate

  • An, Jeongmin;Cho, Jaiesoon
    • Animal Bioscience
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    • v.34 no.3_spc
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    • pp.463-470
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    • 2021
  • Objective: This experiment was conducted to find out the immunological effects of wheat phytase when long-chain inorganic polyphosphate (polyP) treated with wheat phytase was added to a macrophage cell line, Raw 264.7, when compared to intact long-chain polyP. Methods: Nitric oxide (NO) production of Raw 264.7 cells exposed to P700, a long-chain polyP with an average of 1,150 phosphate residues, treated with or without wheat phytase, was measured by Griess method. Phagocytosis assay of P700 treated with or without phytase in Raw 264.7 cells was investigated using neutral red uptake. The secretion of tumor necrosis factor α (TNF-α) by Raw 264.7 cells with wheat phytase-treated P700 compared to intact P700 was observed by using Mouse TNF-α enzyme-linked immunosorbent assay kit. Results: P700 treated with wheat phytase effectively increased NO production of Raw 264.7 cells by 172% when compared with intact P700 at 12 h exposure. At 5 mM of P700 concentration, wheat phytase promoted NO production of macrophages most strongly. P700, treated with wheat phytase, stimulated phagocytosis in macrophages at 12 h exposure by about 1.7-fold compared to intact P700. In addition, P700 treated with wheat phytase effectively increased in vitro phagocytic activity of Raw 264.7 cells at a concentration above 5 mM when compared to intact P700. P700 dephosphorylated by wheat phytase increased the release of TNF-α from Raw 264.7 cells by 143% over that from intact P700 after 6 h exposure. At the concentration of 50 μM P700, wheat phytase increased the secretion of cytokine, TNF-α, by 124% over that from intact P700. Conclusion: In animal husbandry, wheat phytase can mitigate the long-chain polyP causing damage by improving the immune capabilities of macrophages in the host. Thus, wheat phytase has potential as an immunological modulator and future feed additive for regulating immune responses caused by inflammation induced by long-chain polyP from bacterial infection.

Labor Investment Efficiency and Value Relevance of Accounting Information (노동투자효율성이 회계정보의 가치관련성에 미치는 영향)

  • Cho, Jungeun
    • The Journal of the Korea Contents Association
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    • v.20 no.12
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    • pp.136-144
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    • 2020
  • Previous studies report that labor investment inefficiency occurs as the information asymmetry becomes severe and the agency problem between managers and external investors increases. Therefore, it is highly likely that managers will make opportunistic decisions that can damage corporate value in companies with high labor investment inefficiency. This study examines whether the value relevance of accounting information decreases as labor investment inefficiency increases as it is less likely that investors in the market use the accounting information of companies in which labor investment decisions are made inefficiently. Labor investment efficiency is measured as the difference between the actual level of labor investment and the expected level of optimal labor investment. Larger difference between the actual level of labor investment and the expected level of optimal labor investment is considered as higher inefficiency in labor investment. Using data of firms listed on the Korea Stock Exchange from 2002 to 2018, empirical results show that the value relevance of earnings decreases as the inefficiency of labor investment increases. This research provides empirical evidence on whether investment inefficiency in labor, which is an important factor in the competitiveness of a company, reduces the information usefulness of reported earnings.

Semen evaluation: methodological advancements in sperm quality-specific fertility assessment - A review

  • Tanga, Bereket Molla;Qamar, Ahmad Yar;Raza, Sanan;Bang, Seonggyu;Fang, Xun;Yoon, Kiyoung;Cho, Jongki
    • Animal Bioscience
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    • v.34 no.8
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    • pp.1253-1270
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    • 2021
  • Assessment of male fertility is based on the evaluation of sperm. Semen evaluation measures various sperm quality parameters as fertility indicators. However, semen evaluation has limitations, and it requires the advancement and application of strict quality control methods to interpret the results. This article reviews the recent advances in evaluating various sperm-specific quality characteristics and methodologies, with the help of different assays to assess sperm-fertility status. Sperm evaluation methods that include conventional microscopic methods, computer-assisted sperm analyzers (CASA), and flow cytometric analysis, provide precise information related to sperm morphology and function. Moreover, profiling fertility-related biomarkers in sperm or seminal plasma can be helpful in predicting fertility. Identification of different sperm proteins and diagnosis of DNA damage has positively contributed to the existing pool of knowledge about sperm physiology and molecular anomalies associated with different infertility issues in males. Advances in methods and sperm-specific evaluation has subsequently resulted in a better understanding of sperm biology that has improved the diagnosis and clinical management of male factor infertility. Accurate sperm evaluation is of paramount importance in the application of artificial insemination and assisted reproductive technology. However, no single test can precisely determine fertility; the selection of an appropriate test or a set of tests and parameters is required to accurately determine the fertility of specific animal species. Therefore, a need to further calibrate the CASA and advance the gene expression tests is recommended for faster and field-level applications.