• Title/Summary/Keyword: Deleterious effects

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Direction-of-Arrival Estimation : Signal Eigenvector Method(SEM) (도래각 추정 : 신호 고유벡터 알고리즘)

  • 김영수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2303-2312
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    • 1994
  • A high resolution algorithm is presented for resolving multiple narrowband plane waves that are incident on an equispaced linear array. To overcome the deleterious effects due to coherent sources, a number of noise-eigenvector-based approaches have been proposed for narrowband signal processing. For differing reasons, each f these methods provide a less than satisfactory resolution of the coherency problem. The proposed algorithm makes use of fundamental property possessed by those eigenvectors of the spatial covariance matrix that are associated with eigenvalues that are larger than the sensor noise level. This property is then used to solve the incoherent and coherent sources incident on an equispaced linear array. Simulation results are shown to illustrate the high resolution performance achieved with this new approach relative to that obtained with MUSIC and spatial smoothed MUSIC.

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A Case of Intoxication of Ingested Formalin (포르말린에 의한 급성 중독 1례)

  • Baek, Seon-Hee;Kim, Kyung-Hwan;Park, Jun-Seok;Shin, Dong-Wun;Roh, Jun-Young;Lee, Kyoung-Mi;Kim, Ah-Jin
    • Journal of The Korean Society of Clinical Toxicology
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    • v.7 no.1
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    • pp.38-40
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    • 2009
  • Formalin is a water-soluble, colorless, pungent, irritating and highly reactive gas. A 40% solution of formaldehyde in water, also known as formalin, is used as a disinfectant, antiseptic, deodorant, tissue fixative and embalming fluid. Ingestion can lead to immediate deleterious effects on almost all systems of the body including gastrointestinal tract, central nervous system, cardiovsacular system and hepato-renal system, causing gastrointestinal hemorrhage, cardiovsacular collapse, unconsciousness or convulsions, severe metabolic acidosis and acute respiratory distress syndrome. We treated a 39-year-old woman who ingested 300 ml formalin in a suicidal attempt. Despite hemodialysis, death occurred after 23 h.

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Effect of Methylprednisolone Sodium Succinate on Innate Immune Function of Canine Peripheral Blood Phagocytes

  • Park, Moo-Rim;Kang, Ji-Houn;Yang, Mhan-Pyo
    • Journal of Veterinary Clinics
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    • v.25 no.6
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    • pp.440-446
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    • 2008
  • Glucocorticoids (GCs) are the most widely used immunosuppressive agents, but animals treated with GCs may experience deleterious side effects which limit their use in many clinical conditions. In the present study, we examined whether methylprednisolone sodium succinate (MPSS), a glucocorticoid, modulates circulating leukocyte numbers, phagocytic capacity and oxidative burst activity (OBA) of canine peripheral blood phagocytes, and whether tumor necrosis factor-alpha (TNF-$\alpha$) release is affected by MPSS injection. Neutrophilia and monocytosis were induced by the administration of a high dose of MPSS, which is the recommended protocol for canine patients with acute spinal cord injury. The injection of MPSS decreased the phagocytic capacity of canine PMNs but not PBMCs, and recovered 12 hours (hr) after the completion of MPSS dosing. The OBA of both PMNs and PBMCs was suppressed by MPSS, and restored 24 hr after the completion of dosing. The lipopolysaccharide-induced TNF-α release by PBMCs but not PMNs exposed to MPSS was reduced 12 hr after the completion of dosing, and recovered 48 hr after the completion of dosing. These results suggest that the application of MPSS protocol inhibits the innate immune functions of canine peripheral blood phagocytes for short time relatively.

A Diagnostic Ultrasound Imaging System (초음파 영상진단장치)

  • Lee, Seong-Woo
    • Journal of the Korean Society for Nondestructive Testing
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    • v.19 no.3
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    • pp.217-232
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    • 1999
  • The ability to see the internal organs of the human body in a noninvasive way is a powerful diagnostic tool of modern medicine. Among these imaging modalities such as X-ray, MRI, and ultrasound. MRI and ultrasound are presenting much less risk of undesirable damage of both patient and examiner. In fact, no deleterious effects have been reported as a result of clinical examination by using MRI and ultrasound diagnostic equipment. As a result. their market volume has been rapidly increased. MRI has a good resolution. but there are a few disadvantages such as high price. non-real-time imaging capability. and expensive diagnostic cost. On the other hand, the ultrasound imaging system has inherently poor resolution as compared with X-ray and MRI. In spite of its poor resolution, the ultrasound diagnostic equipment is lower in price and has an ability of real-time imaging as compared with the others. As a result. the ultrasound imaging system has become general and essential modality for imaging the internal organs of human body. In this review various researches and developments to enhance the resolution of the ultrasound images are explained and future trends of the ultrasound imaging technology are described.

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A strudyon the improvement of the oxidation resistance for high temperature materials by coating process (코팅에 의한 고온재료의 내산화성 향상을 위한 연구)

  • 강석철;민경안;안연상;김길무
    • Journal of the Korean institute of surface engineering
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    • v.30 no.2
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    • pp.93-103
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    • 1997
  • High temperature materials used in the elevated temperature and corrosive atmosphere must have the good oxidation resistance and preserve their own mechanical properties simultaneously. For the oxidation resistance, it is very important to form a protective oxide scale such as $Al_2O_3$ or $Cr_2O_3$ on the substrate. However, the additions of protective oxide forming elements such as Cr and Al in the alloy to enhance its oxidation resistance are limited due to the deleterious effects on their mechanical properties. PECVD(P1asma Enhanced Chemical Vapor Deposition) coating processes were employed to improve the oxidation resistance at high temperature. Cr and/or A1 were coated on the substrates of Ni and Inconel 600 at various temperatures of 400, 500, $600^{\circ}C$ and at different conditions of specimen surfaces. Then, coated specimens were exposed to isothermal and cyclic oxidation conditions in air at 1000 and $1100^{\circ}C$. In order to enhance the adhesion between the substrate and coated layer, heat treatments of the coated specimens were conducted in a vacuum. At isothermal oxidation experiments, Al-coated Ni specimen showed better oxidation resistance than pure Ni. At cyclic oxidation experiments at $1000^{\circ}C$. Cr and Al-coated specimen showed better oxidation resistance. Cr-coated Inconel 600 had also showed better oxidation resistance due to Cr in the substrate. By PECVD coating process, oxidation resistance could be improved, but it was not improved as expected due to the weakness of the adhesion between the substrate and the coated layer.

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Changes of Proteolytic Enzyme Property by Gamma Irradiation (감마선 조사에 의한 단백질분해효소의 특성변화)

  • Yook, Hong-Sun;Lee, Hyun-Ja;Im, Sung-Il;Kim, Sung;Byun, Myung-Woo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.6
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    • pp.1116-1121
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    • 1997
  • Effects of gamma irradiation onf the activity and the properties(amino acid compositions, in vitro digestibility and SDS-PAGE pattern) of proteolytic enzymes were investigated. The proteolytic activity of soluble human serine protease, enzyme in kiwi and pineapple decreased 10% and 30~65% by 5 kGy and 30 kGy, respectively. In dried pancreatin and lysozyme, the proteolytic and antimicrobial activities decreased 6~14% and 10~20% by 5kGy and 40kGy, respectively. The analysis of above 10kGy-irradiated soluble human serine protease by SDS-PAGE revealed radiolysis of the enzyme into protein or peptides of lower molecular weights. The irradiation of skim milk, hammastein casein, and lysozyme up to 40kGy had no deleterious effect on either the in vitro digestibility or amino acid compositions.

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Strategies for Response and Mitigation of Marine Environmental Damage Caused by Plastic Debris

  • Lee, Jungsub
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.3
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    • pp.439-446
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    • 2021
  • Environmental damage caused by marine plastic debris occurs and has become a major contributor to marine pollution. This study analyzed the current state of marine plastic debris pollution and proposed essential strategies to reduce damage. To assess the current state of pollution arising from marine plastic debris, this study investigated the properties of plastic debris, reviewed case studies of ecological impacts, and examined the inflow and distribution of marine plastic debris. The results of this study indicate that the major deleterious effects of marine plastics are entanglement and ingestion. In addition, the amount of plastic waste entering the sea was estimated to be 230 Mt in 2015 and may increase to 554 Mt in 2050. In this study, three key strategies were proposed to reduce damage and preserve the ecosystem, including: 1) removing plastic debris in the marine environment, 2) limiting the release of plastic debris to the marine environment, and 3) preventing damage to humans and marine life from plastic debris. To minimize the environmental damage caused by marine plastic debris, the proposed response strategies should be implemented in parallel.

Functional Effects of Increased Copy Number of the Gene Encoding Proclavaminate Amidino Hydrolase on Clavulanic Acid Production in Streptomyces clavuligerus ATCC 27064

  • Song, Ju-Yeon;Kim, Eun-Sook;Kim, Dae-Wi;Jesen, Susan E.;Lee, Kye-Joon
    • Journal of Microbiology and Biotechnology
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    • v.18 no.3
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    • pp.417-426
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    • 2008
  • The effect of increasing levels of proclavaminate amidino hydrolase (Pah) on the rate of clavulanic acid production in Streptomyces clavuligerus ATCC 27064 was evaluated by increasing dosoge of a gene (pah2) encoding Pah. A strain (SMF5703) harboring a multicopy plasmid containing the pah2 gene showed significantly retarded cell growth and reduced clavulanic acid production, possibly attributable to the deleterious effects of the multicopy plasmid. In contrast, a strain (SMF5704) carrying a single additional copy of pah2 introduced into chromosome via an integrative plasmid showed enhanced production of clavulanic acid and increased levels of pah2 transcripts. Analysis of transcripts of other genes involved in the clavulanic acid biosynthetic pathway revealed a pattern similar to that seen in the parent. From these results, it appears that clavulanic acid production can be enhanced by duplication of pah2 through integration of a second copy of the gene into chromosome. However, increasing the copy number of only one gene, such as pah2, does not affect the expression of other pathway genes, and so only modest improvements in clavulanic acid production can be expected. Flux controlled by Pah did increase when the copy number of pah2 was doubled, suggesting that under these growth conditions, Pah levels may be a limiting factor regulating the rate of clavulanic acid biosynthesis in S. clavuligerus.

Asymmetric Effects of Inflation Uncertainty on Facilities Investment (인플레이션 불확실성의 기업 설비투자에 대한 비대칭적 효과 분석)

  • Son, Minkyu;Chang, Youngjae
    • The Korean Journal of Applied Statistics
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    • v.27 no.1
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    • pp.123-132
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    • 2014
  • Inflation uncertainty is known to have deleterious effects on facilities investment by disturbing the corporate decision on the opportunity cost of investment. In this paper, we test the validity of this hypothesis in Korea by estimating the inflation uncertainty with both a time-varing parameter model with GARCH disturbances and the relative price volatility and then, estimate the facilities investment equation which includes those uncertainty indicators. The uncertainty indexes estimated by the above-mentioned methods continue to fluctuate even after the inflation rate has dropped dramatically reflecting the structural changes of Korea's economy since the financial crisis in 1997. As a result of estimation of the investment equation by both OLS and GMM, we find the inflation uncertainty has a negative effect on facilities investment with a statistical significance. Moreover, by means of Markov-switching regression model utilized to verify the non-linearity of this relationship, we draw a conclusion that this negative effect of inflation uncertainty heightens asymmetrically during the downturn periods of business cycle.

Amino Acid Imbalance-Biochemical Mechanism and Nutritional Aspects

  • Park, Byung-Chul
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.9
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    • pp.1361-1368
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    • 2006
  • Amino acid imbalances refer to the deleterious effects that occur when a second-limiting amino acid or mixture of amino acid lacking a particular limiting amino acid is supplemented in diets marginal in one or more indispensable amino acids. In spite of variation in the conditions that have been used to induce amino acid imbalances, such as protein level in the diet, the extent of difference in total nitrogen content between basal and imbalanced diets, and kinds of amino acids used as imbalancing agents, the conspicuous common features of amino acid imbalances have been a decreased concentration of the limiting amino acid in blood, depression of feed intake and weight gain, and increased dietary content of the limiting amino acid needed to correct the imbalances. There is strong evidence that a decrease in the concentration of a limiting amino acid detected in the anterior prepyriform cortex of the brain is followed by behavioral effects, especially a decrease in feed intake. This might be due to the competition between the limiting amino acid and the amino acids in the imbalancing mixture for transport from blood into brain. One of the biochemical responses of animals fed amino acid imbalanced diets is a rapid decrease in the concentration of the limiting amino acid, which are due in part to an increase in catabolism of the limiting amino acid by the increased activities of enzymes involved in the catabolism of the amino acid. Practically, specific amino acid imbalances could be induced in swine and poultry diets that have been supplemented with lysine, methionine, tryptophan when threonine, isoleucine, valine, etc. are potentially third- or fourth-limiting in diets. In these cases supplementation of the limiting amino acid could be beneficial in preventing the decrease of feed intake that could otherwise occur as a result of amino acid imbalance.