• Title/Summary/Keyword: HARM

Search Result 849, Processing Time 0.027 seconds

Acute Toxicity Test of Agricultural Chemicals to Water Fleas (물벼룩을 이용한 농약의 급성 독성에 관한 연구)

  • Lee, Chan-Won;Ryu, Jae-Young;Lim, Kyeong-Won
    • Journal of Environmental Science International
    • /
    • v.16 no.1
    • /
    • pp.55-63
    • /
    • 2007
  • There are concerns that chemical residues could harm the consumer on the environment, although 50 to 80% of the crops would be destroyed by pests and others without agrochemicals. Environmental fate and ecotoxicity studies are usually carried out to assess the impact on the human and the environment. A comparision of the Daphnia magnia and Simocephalus mixtus toxicity was performed to study the relative sensitivities and discrimination abilities to agriculture chemicals. The species of Simocephalus mixtus was more sensitive to agriculture chemicals than Daphnia magnia. Simocephalus mixtus was approved to be a water flea in determining insecticide and pesticide toxicity by heart-beat rate in a consistency and repeatability. The order of acute toxicity to water flea Daphnia magnia for ecotoxicity test was carbaryl>benomyl>amtirole with both Daphnia magnia and Simocephalus mixtus. The heartbeat pattern after the exposure to agrochemicals was different from that of exposure to heavy metals. Agrochemical leathal concentration test with heartbeat rate measurement was found to be more appropriate than inhibition concentration test with respect to toxicological endpoint.

Criteria of Impact Resistance of Lightweight Wall by the Large Soft Body (건식 경량벽체의 연질 충격체에 의한 내충격성 판정기준에 관한 연구)

  • Kim, Ki Jun;Song, Jung Hyeon;Choi, Soo Kyung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2014.05a
    • /
    • pp.102-103
    • /
    • 2014
  • Due to the nature of the existing load, the criteria of assessing the intensity of the lightweight wall's impact resistance has been though of as obscure. The current study, therefore, focuses on the standardized assessment of the impact resistance to the force of the large soft body applying to the lightweight wall. The gypsum board wall showed a low level of the maximum residual displacement. It is, however, required to be careful about the selection of the finishing process since the high level of the maximum displacement is likely to cause harm to finishing materials. Unlike the gypsum board, the ALC block wall displayed a considerable rigidity while showing almost no maximum residual displacement. Even with the low level of the maximum displacement due to the stiffness, the ALC block wall is still likely to be affected by the vibration derived from any impact on the surface, which demands a need for additional study. The future experimental study, accordingly, will focus on the impact of the vibration on finishing materials, consequently leading to the accurate prediction of the possibility of potential damage to the lightweight wall caused by the large soft body.

  • PDF

An experimental study on the Performance Evaluation of High Performance Polyurea Resins (고성능 폴리우레아 수지의 기본적 물리/화학적 성능평가에 관한 실험적 연구)

  • Kim, Yun-Ho;Choi, Eun-Kyu;Seo, Hyun Jae;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2011.11a
    • /
    • pp.43-45
    • /
    • 2011
  • As technologies evolve, building large concrete structures ever built, but due to lack of maintenance after completion of concrete corrosion, leaks, and preparedness from the problem that is an urgent need. In particular, water-resistant variety of concrete structures. How the concept applies to the most important public drinking water purification and drinking water that is draining the production and storage, and distribution as the structure cause damage to the structure when the contaminated water is supplied to each home that can harm the health of citizens is the cause. Therefore, the correct choice of materials, and thorough a lot of investment in construction and maintenance should have. In this study, unlike conventional water-proof materials, methods, and in other reactions easily than conventional poly-urea resins have good physical performance and chemical resistance, high performance polyurea resin performance review of the physical infrastructure of the country for the longevity of would like to make long-term durability.

  • PDF

Control of Singlet Oxygen-induced Oxidative Damage in Escherichia coli

  • Kim, Sun-Yee;Kim, Eun-Ju;Park, Jeen-Woo
    • BMB Reports
    • /
    • v.35 no.4
    • /
    • pp.353-357
    • /
    • 2002
  • Singlet oxygen ($^1O_2$) is highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules. The oxyR gene product regulates the expression of the enzymes and proteins that are needed for cellular protection against oxidative stress. In this study, the role of oxyR in cellular defense against a singlet oxygen was investigated using Escherichia coli oxyR mutant strains. Upon exposure to methylene blue and visible light, which generates singlet oxygen, the oxyR overexpression mutant was much more resistant to singlet oxygen-mediated cellular damage when compared to the oxyR deletion mutant in regard to growth kinetics, viability and protein oxidation. Induction and inactivation of major antioxidant enzymes, such as superoxide desmutase and catalase, were observed after their exposure to a singlet oxygen generating system in both oxyR strains. However, the oxyR overexpression mutant maintained significantly higher activities of anticxidant enzymes than did the oxyR deletion mutant. These results suggest that the oxyR regulon plays an important protective role in singlet oxygen-mediated cellular damage, presumably through the protection of antioxidant enzymes.

Stimulating Online Communities-of-Practice: The Influence of Sponsors in Organizations (온라인 실행공동체(Communities-of-Practice) 활성화 요인과 스폰서의 영향)

  • Koh, Joon;Om, Ki-Yong
    • Asia pacific journal of information systems
    • /
    • v.16 no.2
    • /
    • pp.183-203
    • /
    • 2006
  • Firms are increasingly adopting online communities-of-practice (CoPs) with strong managerial support in hopes of promoting knowledge sharing and creation within the organization. Excessive managerial concern and sponsoring, however, could harm the spontaneity of CoP participants, which is one of the pivotal characteristics of virtual communities, and in the end, have negative impact on their smooth operation. In this regard, this study examines the factors which affect the stimulation of CoPs and explores the difference in their operating mechanisms under two differing organizational structural settings by the existence of a sponsor. By analyzing 133 samples of CoPs in a globally leading company, this study found that the existence of a sponsor designated by the organization, has serious influence on the working of CoPs, That is, leaders' enthusiasm and the level of off-line activities are critical factors for the stimulation of CoPs which have no sponsor, while in case of CoPs that have their sponsors, neither leaders' enthusiasm nor the level of off-line activities are significantly related to the stimulation of CoPs. At the same time, the performance of CoPs which have their sponsors was found significantly higher than that of CoPs which have no sponsor. These results indicate that firms need to pay special attention to organizational sponsorship when introducing CoPs within their organizations.

Study on Conceptual Factor s and Types of Korean Medical Practice (한방의료행위의 개념요소와 유형에 관한 법적 고찰)

  • Lee, Boo-Kyun
    • The Korean Society of Law and Medicine
    • /
    • v.13 no.2
    • /
    • pp.263-284
    • /
    • 2012
  • Medical Act. article 2 (3) stipulates that "a korean medicine doctor is in charge of providing korean medical practices and korean medical health guidance". But, without a definition article about korean medical practice, the legal concept of it is defined by supreme court cases according to specific legal trials. To establish the concept of korean medical practice, it must be included that the common parts of practice of medicine involving "the purpose of practice", "the subject of practice", "the object of practice" and "other dangers", as well as the special parts of conceptual elements of korean medical practice involving "korean medicine principle" and "differentiation" and also "manufacturing of korean medicine". Accordingly, the definition of korean medical practice is defined as examining, diagnosing, differentiating, prescribing, manufacturing of korean medicine, treating, korean medical care guiding so as to treat diseases and to promote and to maintain health, based on korean medicine as traditionally handed down from the nation's ancestors and korean medicine principle which is scientifically developed and applied and also includes a practice that will cause physiological danger to human body and/or bring harm to public health and sanitation if it is not perfomed by korean medicine doctor.

  • PDF

A Surface Adaptive Moving Mechanism for Wind Turbine Blade Maintenance Robot (풍력발전기 유지보수로봇을 위한 표면 적응 이동 시스템)

  • Kim, Byunggon;Park, Sora;Jun, Minsoek;Jun, Kyungtae;Hong, Daehie
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.9
    • /
    • pp.969-975
    • /
    • 2013
  • As energy shortage is getting more serious, wind energy source is more promoted around the world. Blade is a key component of wind turbine. Local breakages and/or contamination in the blade bring degradation in aerodynamic efficiency and life-time. However, it is not easy and even dangerous for human workers to access the blade for inspection and maintenance since its size is huge and located at high mountains and rough sea, which are windy places. This paper deals with a novel moving mechanism that efficiently carries human workers or robots to the wind turbine blade. The proposed mechanism utilizes flexible tube with pressurized air that rolls and climbs over the blade surface. So, the tube naturally adapts the changing surface of the blade and acts no harm to it. This paper discusses about its concept, detail design, and advantages. The feasibility of the proposed mechanism is proved through experiments prototype.

High-speed angular-scan pulse-echo ultrasonic propagation imager for in situ non-destructive evaluation

  • Abbas, Syed H.;Lee, Jung-Ryul
    • Smart Structures and Systems
    • /
    • v.22 no.2
    • /
    • pp.223-230
    • /
    • 2018
  • This study examines a non-contact laser scanning-based ultrasound system, called an angular scan pulse-echo ultrasonic propagation imager (A-PE-UPI), that uses coincided laser beams for ultrasonic sensing and generation. A laser Doppler vibrometer is used for sensing, while a diode pumped solid state (DPSS) Q-switched laser is used for generation of thermoelastic waves. A high-speed raster scanning of up to 10-kHz is achieved using a galvano-motorized mirror scanner that allows for coincided sensing and for the generation beam to perform two-dimensional scanning without causing any harm to the surface under inspection. This process allows for the visualization of longitudinal wave propagation through-the-thickness. A pulse-echo ultrasonic wave propagation imaging algorithm (PE-UWPI) is used for on-the-fly damage visualization of the structure. The presented system is very effective for high-speed, localized, non-contact, and non-destructive inspection of aerospace structures. The system is tested on an aluminum honeycomb sandwich with disbonds and a carbon fiber-reinforced plastic (CFRP) honeycomb sandwich with a layer overlap. Inspection is performed at a 10-kHz scanning speed that takes 16 seconds to scan a $100{\times}100mm^2$ area with a scan interval of 0.25 mm. Finally, a comparison is presented between angular-scanning and a linear-scanning-based pulse-echo UPI system. The results show that the proposed system can successfully visualize defects in the inspected specimens.

Types of Cancers Prevailing in Pakistan and their Management Evaluation

  • Tariq, Ayesha;Majeed, Imtiaz;Khurshid, Azhar
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.9
    • /
    • pp.3605-3616
    • /
    • 2015
  • Cancer is basically a class of disorder marked by uncontrolled proliferation of cells which have the potential to interfere with different systems of body like digestive, central nervous and circulatory systems by releasing hormones. Tumors that reside only in a specified location and show restricted growth are commonly characterized as benign tumors. When tumor cells grow and effectively spread to other body parts and potentially invade and damage healthy tissues they show various degrees of malignancy. Cancer may be caused by different factors like gene mutations, carcinogens and some medical factors that harm the immune system of the body. Symptoms of cancer are relatively varied and classified according to location, progression pattern and size of tumors as well. Different diagnostic tests are used for evaluation that depends on the type of cancer. Cancer management and chemo protocols also depend on the progression and site where it develops. Cancers like breast, lung, liver, colorectal, prostate, head and neck carcinoma are most commonly diagnosed in Pakistan. This review briefly describes the three most common cancers prevailing in Pakistan and their management evaluation.

Extracting gall bladders from ultrasound images

  • Kim, Hyoung-Seop;Ishikawa, Seiji;Kato, Kiyoshi;Tsukuda, Masaaki;Matsuoka, Jun-nosuke
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1995.10a
    • /
    • pp.248-251
    • /
    • 1995
  • Nowadays, the internal images of a human body can be easily provided by the ultrasound imaging, the X-ray CT, or the MRI device, among which the ultrasound imaging device has good resolution for soft tissues of a human body compared with the other devices. Furthermore, the use of ultrasound imaging devices will increase in future especially in the obstetrics, territory, since it does not give harm to the human body. Although several techniques have been investigated until now in order to extract organs from ultrasound images, very few of them have achieved satisfactory results because of low contrast and high noise nature of images. This paper proposes a technique for automatic extraction of the gall bladder area from ultrasound images. The proposed technique first extracts a small reliable area of a gall bladder from an ultrasound image employing smoothing, binarization, expanding and shrinking, and labeling, and then expands the area referring to the binarized version of the original image. The technique is examined its performance by real ultrasound images of a gall bladder and satisfactory results are obtained. Some problems to be solved are discussed finally.

  • PDF