• Title/Summary/Keyword: Impact damage

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The Physio-ecological Characteristics of Golden Apple Snails (Pomacea canaliculata) and the Cause of Their Massive Death used for Weed Control in Wet Rice Paddies (왕우렁이(Pomacea canaliculata)의 생리·생태학적 특성 및 논 잡초방제용으로 투입된 왕우렁이의 집단패사 원인)

  • Lee, Sang-Beom;Lee, Sang-Min;Ko, Byong-Gu;Lee, Cho-Rong;Kim, Jin-Ho
    • Korean Journal of Organic Agriculture
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    • v.26 no.2
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    • pp.297-316
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    • 2018
  • The golden apple snail (GAS, Pomacea canaliculata) is an invasive freshwater snail. The GAS was introduced in Korea without prior studies on the possibility of crop damage or its impact on the natural ecosystem. The freshwater apple snails can be found typically in ponds, rice paddies, irrigation canals, roadside ditches or slower portions of streams. In this study, we were carried out to investigate the assessment of physiological and ecological characteristics, environmental characteristics inhabited area in winter season and cause of massive death at one time of golden apple snails used for weed control in wet rice paddies. The GAS was introduced from Japan to Korea for commercial production as a dietary protein supplement. The golden apple snail was also used a recently for weed control in wet rice cultivation. The species of freshwater Pomacea snails is belonging to the genus Pomacea, family ampulariidae, order mesogastropoda, subclass pulmonata, class gastropoda, phylum mollusca. The GAS spread into irrigation ditches and natural waterways. It is now distributed in ponds and canals near rice fields of southern parts of the country and has overwintered. It increases its cold hardiness before winter. However, the physiological mechanism of cold hardiness in molluscs is poorly understood, especially in freshwater molluscs. Our results on physio-ecological characteristics of the Pomacea apple snail showed that the ratio of males to females was 1: 1.99~2.33. The daily growth was 87.7 mg in weight, 0.31 mm in height and 0.33 mm in width of the their shell. On the other hand, the golden apple snails were very high to resistance on drying condition and survived rate about 80% up to 3 months. The inhabitation of GAS was no statistical significant impacts on the water quality. An important property of aqueous solutions is agricultural water quality because it affects chemical and biochemical properties such as chemical reactions, equilibrium conditions, and biological toxicity. The death rate of weed control apple snails by Ostracoda (Stenocypris hislopi) was only 2.86% and 5.71% depending on the density. Therefore, GAS was not a direct death caused by Ostracoda (Stenocypris hislopi).

A Comparison of Single and Multi-matrix Models for Bird Strike Risk Assessment (단일 및 다중 매트릭스 모델의 비교를 통한 항공기-조류 충돌 위험성 평가 모델 분석)

  • Hong, Mi-Jin;Kim, Myun-Sik;Moon, Young-Min;Choi, Jin-Hwan;Lee, Who-Seung;Yoo, Jeong-Chil
    • Korean Journal of Environment and Ecology
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    • v.33 no.6
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    • pp.624-635
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    • 2019
  • Bird strike accidents, a collision between aircraft and birds, have been increasing annually due to an increasing number of aircraft operating each year to meet heavier demand for air traffic. As such, many airports have conducted studies to assess and manage bird strike risks effectively by identifying and ranking bird species that can damage aircraft based on the bird strike records. This study was intended to investigate the bird species that were likely to threaten aircraft and compare and discuss the risk of each species estimated by the single-matrix and multi-matrix risk assessment models based on the Integrated Flight Information Service (IFIS) data collected in Gimpo, Gimhae and Jeju Airports in South Korea from 2005 to 2013. We found that there was a difference in the assessment results between the two models. The single-matrix model estimated 2 species and 6 taxa in Gimpo and Gimhae Airports and 2 species and 5 taxa in Jeju Airport to have the risk score above "high," whereas the multi-matrix model estimated 3 species and 5 taxa in Gimpo Airport, 4 species and 5 taxa in Gimhae Airport, and 2 species and 3 taxa in Jeju Airport to have the risk score above "very high." Although both models estimated the similar high-risk species in Gimpo and Gimhae Airports, there was a significant difference in Jeju Airport. Gimpo and Gimhae Airports are near the estuary of a river, which is an excellent habitat for large and heavy waterbirds. On the other hand, Jeju Airport is near the coast and the city center, and small and light bird species are mostly observed. Since collisions with such species have little effect on aircraft fuselage, the impact of common variables between the two models was small, and the additional variables caused a significant difference between the estimation by the two models.

Health-related Quality of Life Measurement with St. George's Respiratory Questionnaire in Post-tuberculous Destroyed Lung (결핵후 폐손상에서 한국어판 St. George's Respiratory Questionnaire를 이용한 건강 관련 삶의 질 평가)

  • Lee, Byoung Hoon;Kim, Young Sam;Lee, Ki Deok;Lee, Jae Hyung;Kim, Sang-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.65 no.3
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    • pp.183-190
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    • 2008
  • Background: The control of active pulmonary tuberculosis is still an issue in community medicine. But there are also considerable needs for supportive management of symptomatic patients with post-tuberculous destroyed lung. Few studies have evaluated clinical characteristics and health-related quality of life in patients with post-tuberculous destroyed lung. Methods: We evaluated lung function, exercise tolerance, HRCT and health-related quality of life measurements using the Korean version of St. George's Respiratory Questionnaire (SGRQ) in 22 patients with parenchymal damage to more than a half of one lung due to pulmonary tuberculosis. Results: In the pulmonary function test, mixed defects and obstructive defects were observed in 10 (45.0%) and 9 (40.9%) of patients, respectively. In the cardiopulmonary exercise test, the mean $VO_2max%$ predicted ($39.0%{\pm}10.9%$) and $O_2$ pulse% predicted ($61.3%{\pm}13.6%$) were markedly decreased. In the SGRQ, the impact score (mean $27.8{\pm}18.5$) was significantly lower than the symptom score (mean $53.9{\pm}20.9$) or activity score (mean $50.8{\pm}27.3$) (p<0.05, p<0.01). Cronbach's alpha coefficient value for reliability was more than 0.7 for each subscale and total score. The total score showed a significant negative correlation with $FEV_1%$ predicted (r=-0.46, p<0.05) and $SaO_2$ (r=-0.60, p<0.05). On HRCT, a median of 9 (range 5~15) bronchopulmonary segments were destroyed by less than half, which significantly correlated with SGRQ total score (r=-0.52, p=0.02). Conclusion: The reliability and validity of the Korean version of the SGRQ was acceptable for the measurement of health-related quality of life in patients with post-tuberculous destroyed lung.

Efficacy of Genetic Adjuvant (Plasmid-Expressed Chicken Interleukin-6) and Chemical Adjuvant (Levamisole) on the Protective Immunity of Genetic Vaccine against Infectious Bursal Disease Virus (닭의 전염성 F낭병 바이러스 유전자백신에 의한 방어 면역에 Genetic Adjuvant (Chicken Interleukin-6)와 Chemical Adjuvant (Levamisole)의 효과)

  • Park, Jeong-Ho;Sung, Haan-Woo;Yoon, Byung-Il;Pak, Son-Il;Kwon, Hyuk-Moo
    • Korean Journal of Microbiology
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    • v.45 no.2
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    • pp.91-98
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    • 2009
  • Infectious bursal disease (IBD) caused by the infectious bursal disease virus (IBDV) has an important economic impact on the poultry industry worldwide. This study examined the adjuvant effects of a plasmid encoding chicken interleukin-6 (pcDNA-ChIL-6) and levamisole (LMS) on in ovo prime-boost vaccination using a genetic vaccine (pcDNA-VP243) to prime in chicken followed by a killed-vaccine boost. A pcDNA-VP243 was injected into the amniotic sac alone or in combination with a pcDNA-ChIL-6 or LMS at embryonation day 18, followed by an intramuscular injection of killed IBD vaccine at 1 week of age. The chicken were orally challenged with very virulent IBDV (vvIBDV) strain at 3 weeks of age and observed for 10 days. No mortality was observed in the groups that received the pcDNA-VP243 alone and pcDNA-VP243 plus pcDNA-ChIL-6 or LMS compared to 100% mortality in unvaccinated challenge control group. However, as determined by bursal damage (the presence of IBDV RNA, B/B ratio, and lesion score), a pcDNA-VP243 alone group was superior to pcDNA-VP243 plus pcDNA-ChIL-6 or LMS groups in the protection against post-challenge. These findings suggest that in ovo priming with genetic vaccine and boosting with killed vaccine is an effective strategy for protecting chicken against vvIBDV and the addition of pcDNA-ChIL-6 or LMS did not enhance protective immunity.

A Study on the Location of Zen Buddhist Temples During the Late Silla Dynasty in Korea - from Feng-shui(風水) Perspective - (신라말 구산선문(九山禪門) 사찰의 입지 연구 - 풍수적 측면을 중심으로 -)

  • Cho, Sung-Ho;Sung, Dong-Hwan
    • Journal of the Korean association of regional geographers
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    • v.6 no.3
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    • pp.53-81
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    • 2000
  • The purpose of this study is to examine the chracteristics of the location of Zen Buddhist temples which are the Nine-Mountain Sects of Zen(九山禪門) from feng-shui perspective. A large number of temples have been built for about 1600 years since Buddhism had influenced on Korea. They have been built nationwide in different times by different sects of Buddhism. The pattern of location of Buddhist temples is different according to background of the times (political, economic, cultural aspect) and of tenet(difference in sects of Buddhism) when the temples were built. But the general location of Korean Buddhist temples is in accordance with feng-shui theory. Feng-shui is a traditional geographic thought in China and Korea. It is necessary to understand feng-shui in order to understand Korean landscape and cultural geography. It had given a tremendous impact on Korean landscape through choosing site of cities, settlements, houses, mounments, temples, pagodas, and so on. Before feng-shui was prevailing in Korea, Buddhist temples were mostly built on sacred place which was connected with folk beliefs. In the case of the late Silla Dynasty when Zen Buddhism was prevailing, feng-shui became popular and many. temples were built in accordance with feng-shui. The typical examples are found in the site of Nine-Mountain Sects of Zen temples. The interpretation of geomantic site of Nine-Mountain Sects of Zen temples will show us how feng-shui was applied to and reflected in the Korean peninsula. In Zen Buddhism, feng-shui was applied to the choice of the temple site. Also feng-shui theory was usually used to choose the site of stupa(Budo) where the remains of the founder of sect. In this study, I will interpret the geomantic characteristics of Nine-Mountain Sects of Zen temples. The geomantic interpretations of the temples are as follow. 1. The temples are located at the foot of a hill with surrounding mountains and a watercourse in front. Feng-shui texts often describe it as an ideal site. This geomantic situation is well equipped with natural drainage; protection from cold wind from the north or evil spirits; a good view with open space to the front; protection from unnecessary weather damage; and security and protection from strangers and invaders. 2. The sitting and facing direction of the temples correspond to the oncoming dragon's direction. 3. Many feng-shui texts discuss the types of Sa(surrounding mountains) in detail and morphologically describe them with certain animate and inanimate auspicious objects. In case of Nine-Mountain Sects of Zen temples, the geomantic landscape of these can be compared to auspicious objects. This is morphological marker for the description of configulation features of these temples. 4. Most auspicious places are not perfect, but the shortcomings can be overcome by many means. We can observe modification of landscape for the purpose of fulfilling the geomantic harmony of the temple.

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The difference of photosynthetic efficiency and electron transport rate by control of the red tide organism using algicidal substance and yellow clay (살조물질과 황토를 이용한 적조생물 제어에 따른광합성 효율 및 전자전달율의 차이)

  • Son, Moonho;Baek, Seung Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2951-2957
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    • 2015
  • The development of worldwide harmful algal blooms(HAB) is a serious problem for public health and fisheries industries. To evaluate the algicidal impact on the HAB species, algicide thiazolidinedione derivative (TD49) and yellow clay were examined, which is focus on assess the algicidal effects and inhibition to photosynthesis of HAB species. To obtain the detailed information, we analyzed the viability of target species related to activity Chl. a, photosynthetic efficiency($F_v/F_m$), and electron transport rate(ETR). Culture experiment was conducted to evaluate the algicidal effects of three harmful species(raphidophyceae Heterosigma akashiwo, Chattonella marina, and dinophyceae Heterocapsa circularisquama) and one non-harmful species (cryptophyceae Rhodomonas salina). Our experiments revealed that three HAB species were easily destroyed of the cell walls after TD49 dosing. Also, they had significantly reducing values of active Chl. a, $F_v/F_m$, and ETR, due to the damage of photosystem II by inter-cellular disturbance. As a result, the algicidal effect(%) for the three HABs were as follows, in the order of greatest to the least: H. circularisquama> C. marina> H. akashiwo. However, the algicidal effect for yellow clay remained to be <30% (p>0.01), implying that it may not have damaged the photosystem II. On the other hand, non-HAB R. salina was promoted at both TD49 and yellow clay treatments. Our results demonstrated that the TD49 is a good agent for the control of HABs H. akashiwo, C. marina, and H. circularisquama, whereas the yellow clay would not be suitable for the field application based on our experimental results.

Development of a Thermoplastic Oral Compensator for Improving Dose Uniformity in Radiation Therapy for Head and Neck Cancer (두경부암 방사선치료 시 선량 균일도 향상을 위한 Thermoplastic 구강 보상체의 개발)

  • Choi, Joon-Yong;Won, Young-Jin;Park, Ji-Yeon;Kim, Jong-Won;Moon, Bong-Ki;Yoon, Hyong-Geun;Moon, Soo-Ho;Jeon, Jong-Byeong;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.23 no.4
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    • pp.269-278
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    • 2012
  • Aquaplast Thermoplastic (AT) is a tissue-equivalent oral compensator that has been developed to improve dose uniformity at the common boundary and around the treated area during radiotherapy in patients with head and neck cancer. In order to assess the usefulness of AT, the degree of improvement in dose distribution and physical properties were compared to those of oral compensators made using paraffin, alginate, and putty, which are materials conventionally used in dental imprinting. To assess the physical properties, strength evaluations (compression and drop evaluations) and natural deformation evaluations (volume change over time) were performed; a Gafchromic EBT2 film and a glass dosimeter inserted into a developed phantom for dose verification were used to measure the common boundary dose and the beam profile to assess the dose delivery. When the natural deformation of the oral compensators was assessed over a two-month period, alginate exhibited a maximum of 80% change in volume from moisture evaporation, while the remaining tissue-equivalent properties, including those of AT, showed a change in volume that was less than 3%. In a free-fall test at a height of 1.5 m (repeated 5 times as a strength evaluation), paraffin was easily damaged by the impact, but AT exhibited no damage from the fall. In compressive strength testing, AT was not destroyed even at 8 times the force needed for paraffin. In dose verification using a glass dosimeter, the results showed that in a single test, the tissue-equivalent (about 80 Hounsfield Units [HU]) AT delivered about 4.9% lower surface dose in terms of delivery of an output coefficient (monitor unit), which was 4% lower than putty and exhibited a value of about 1,000 HU or higher during a dose delivery of the same formulation. In addition, when the incident direction of the beam was used as a reference, the uniformity of the dose, as assessed from the beam profile at the boundary after passing through the oral compensators, was 11.41, 3.98, and 4.30 for air, AT, and putty, respectively. The AT oral compensator had a higher strength and lower probability of material transformation than the oral compensators conventionally used as a tissue-equivalent material, and a uniform dose distribution was successfully formed at the boundary and surrounding area including the mouth. It was also possible to deliver a uniformly formulated dose and reduce the skin dose delivery.

The Impact of Cooking on the Antioxidative and Antigenotoxic Effects of Rice (호화과정이 백미, 현미, 발아현미의 항산화 및 항유전 독성 활성에 미치는 영향)

  • Kim, So-Yun;Seo, Bo-Young;Park, Eunju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.9
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    • pp.1370-1377
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    • 2013
  • Rice is widely grown in Asia and is one of the major dietary staples in the world. Also, rice contains antioxidants which can prevent from oxidative stress related diseases, including cancer, atherosclerosis, and diabetes. Because the rice is consumed cooked, the effect of the cooking process on the antioxidative and antigenotoxic properties of rice is lacking. The aim of this study was to determine the effects of cooking on the antioxidant and antigenotoxic effects of white rice (WR), brown rice (BR), and germinated brown rice (GBR). The antioxidant activities were measured for total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total antioxidant capacity (TRAP), and oxygen radical absorbance capacity (ORAC). The highest TPC was found in uncooked BR (18.4 mg gallic acid equivalent/100 g). After cooking, the TPC of WR significantly increased, while the TPC of BR and GBR were reduced by 47.7% and 36.7%, respectively. The $IC_{50}$ for DPPH RSA was not significantly different in uncooked rice, while the DPPH RSA of WR and GBR decreased after cooking and the DPPH RSA of BR significantly increased. TRAP values in BR and GBR increased after cooking, while the value of WR decreased. The ORAC values of uncooked WR, BR, and GBR were 5.3, 4.3, and $3.9{\mu}M$ trolox equivalent at the concentration of $50{\mu}g/mL$. After cooking, the ORAC value of BR remained unchanged, while the value of GBR increased and the value of WR decreased. The antigenotoxic activities of WR, BR, and GBR were determined by measuring the inhibitory effects of $H_2O_2$-induced DNA damage on human leukocytes using the comet assay. The results showed that all rice tested showed a significant antigenotoxic effect against oxidative stress, except for the cooked white rice. Overall, our results indicate the addition of brown rice and/or germinated brown rice to cooked white rice is a good option for improving the benefits of rice.

Behavior Analysis of Fill Slope by Vehicle Collision on Guardrail (가드레일에 차량 충돌 시 성토사면의 거동분석)

  • Park, Hyunseob;Ahn, Kwangkuk
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.2
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    • pp.67-74
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    • 2014
  • Recently, the number of road construction is increasing by industrial development. According to this industrial tendency, the number of traffic accidents are consistently increasing due to increasing number of vehicle on the road. This is mainly because traffic accidents are occurred by various parameter such as negligence of driver, vehicle defects, state of unstable road, natural environment etc. Lane department of vehicles from guardrail is occurring frequently. This type of accident is caused by vehicle performance improvement and shape of vehicle, weak guardrail installation and maintenance. Guardrail has the purpose on prevention such as prevention of traffic accident and prevention of deviating out of road, minimizing damage of driver and vehicle by collision as well as entry into the road through guardrail. Stability evaluation test of guardrail verifies the behavior of guardrail through the crash of truck. At this time, the crash condition has 100 km/h of velocity and $15^{\circ}$ of impact angle. In the case of ground condition, filling slope condition has relatively high bearing capacity of infinite ground towards the test. Guardrail is generally installed on road of shoulder in fill slope in korea. It is possible for stability problem to deteriorate ground bearing capacity in Guardrail in fill slope. The existed study towards stability of guardrail has been carried out in the infinite ground. However, the study on the behavior of fill slope with guardrail is not performed by vehicle collision. Therefore, In this study, the numerical analysis using LS-DYNA was executed for verification on behavior of fill slope with guardrail through vehicle collision. This numerical analysis was carried out with change of embedded depth on installed guardrail post in shoulder of fill slope by vehicle collision and 8 tonf truck crash providing at NCAN (National Crash Analysis Center). As the result, displacement and stress on fill slope are decreased in accordance with the increase of embedded depth of guardrail post. Ground bearing capacity is deteriorated at depth of 450 mm form shoulder of road on fill slope.

The Present State of Marine Oil Spills and the Enhancement Plans of National Oil Spill Response Capability in Vietnam - Through the Comparison of Statistics and OSR System between Vietnam and Republic of Korea - (베트남의 해양기름유출 현황과 국가대응역량 증강 방안 - 통계자료와 유출유 방제시스템에 대한 베트남과 한국 간의 비교를 통하여 -)

  • Phan, Van Hung;Kim, Kwang-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.6
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    • pp.690-698
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    • 2017
  • Vietnam is a marine nation with more than 3,444 km of shorelines, thousands of islands, and 2,360 rivers and canals of over 42,000 km long. As the frequency and the volume of oil transportation by ships increase, the possibility of oil spill incidents becomes higher than ever. Fuel oil and cargo oil spills at sea have widespread impact and long-term consequences on marine ecosystems, coastal resources and human health as well as socio-economy. This study is to show not only the present state of marine oil spills in Vietnam such as the number and the volume of oil spills for two decades, and an overall about Vietnamese national response system like national framework for Oil Spill Response (OSR), etc. but also to present the recommendations for enhancing national capability in response to oil spill incidents in Vietnam, especially, with a comparison of national OSR systems between Vietnam and South Korea. As the result, the number and the volume of marine oil spills in Vietnam showed an upward trend as opposed to a downward trend in South Korea. This means that Vietnam has the possibility of oil spills in coastal waters. Therefore, three main recommendations for the enhancement of national OSR capability in Vietnam are proposed as follows: (1) the development of alternative plan for reenforcing national OSR system involving legal system for preparedness and response to oil spill pollution such as the acceptance and implementation of OPRC Convention as well as the establishment of national fund compensating for the damage and loss caused by oil pollution; (2) the enhancement of a consistent reporting, alerting and monitoring system; and (3) the development of training and exercise programs with standard contents of educational courses.