• Title/Summary/Keyword: surface accumulation

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Spatio-temporal Distributions of Organic Matter in Surface Sediment in the Central Part of the South Sea, Korea (남해 중부해역 표층퇴적물 유기물의 시.공간 분포특성)

  • Noh, Il-Hyeon;Yoon, Yang-Ho;Park, Jong-Sick;Soh, Ho-Young;Kim, Dae-Il
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.9 no.4
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    • pp.203-215
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    • 2006
  • Field observations on the spatio-temporal distribution of organic matter of the surface sediment were carried out at 15 stations in the central parts of the South Sea of Korea from April 2002 to January 2003. The range of water temperature and salinity in bottom waters, mud content and water content of surface sediment were $8.06{\sim}23.35^{\circ}C,\;29.20{\sim}34.51\;psu,\;71.2{\sim}99.9%$ and $38.7{\sim}68.9%$, respectively. Measured parameters on the surface sediments of ignition loss (IL), chemical oxygen demand (CODs), phaeopigment, particulate organic carbon (POC) and particulate organic nitrogen (PON) also ranged in $3.9{\sim}l2.5%,\;9.60{\sim}44.05\;mgO_2/g-dry,\;1.58{\sim}29.51\;{\mu}g/g-dry,\;3.12{\sim}13.01\;mgC/g-dry$ and $0.49{\sim}2.00\;mgN/g-dry$, respectively. The spatio-temporal distribution of organic matter demonstrated higher concentrations offshore than at lesions near the coastal line. Higher concentrations occurred in the summer and spring. The results indicated that the origin of organic matter in surface sediments in the central part of the South Sea was autochthonous rather than allocthonous because the organic matter had an average C/N ratio of 6.44 (${\pm}0.51$). However, the composition of autochthonous organic matter was mainly derived from detritus rather than living phytoplankton, which was Indicated by the results of the POC/phaeopigment ratio. A principal component analysis (PCA) indicated that 73.2% of the variability in the data was described by two factors: 1) an 'environmental factor concerning the accumulation of materials (57.3%)' and 2) 'origin of organic matter and the composition by primary production (15.9%)'. The sedimentary environment in the central part of the South Sea was divided into four regions from the factor score of the PCA by the concentrations of organic matter and the composition ratio of organic matters from phytoplankton in surface sediments.

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Promoter Analysis of the Cell Surface-abundant and Hypoviral-regulated Cryparin Gene from Cryphonectria parasitica

  • Kim, Myoung-Ju;Kwon, Bo-Ra;Park, Seung-Moon;Chung, Hea-Jong;Yang, Moon-Sik;Churchill, Alice C.L.;Van Alfen, Neal K.;Kim, Dae-Hyuk
    • Molecules and Cells
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    • v.26 no.5
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    • pp.496-502
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    • 2008
  • Cryparin, encoded as a single copy gene (Crp) of the chestnut blight fungus Cryphonectria parasitica, is the most abundant protein produced by this fungus. However, its accumulation is decreased remarkably in C. parastica strains containing the double-stranded (ds) RNA virus Cryphonectria hypovirus 1. To characterize the transcriptional regulatory element(s) for strong expression and viral regulation, promoter analysis was conducted. Serial deletion of the Crp promoter region resulted in a step-wise decrease in promoter activity, indicating a localized distribution of genetic elements in the cryparin promoter. Promoter analysis indicated two positive and a repressive cis-acting elements. Among them, the promoter region between nt -1,282 and -907 appeared to be necessary for hypoviral-mediated down-regulation. An electrophoretic mobility shift assay (EMSA) on the corresponding promoter region (-1,282/-907) indicated two regions at (-1,257/-1,158) and (-1,107/-1,008) with the characteristic AGGAGGA-N42-GAGAGGA and its inverted repeat TCCTCTC-N54-TCCTCCT, respectively, appeared to be specific binding sites for cellular factors.

The Effect of Aircraft Traffic Emissions on the Soil Surface Contamination Analysis around the International Airport in Delhi, India

  • Ray, Sharmila;Khillare, P.S.;Kim, Ki-Hyun
    • Asian Journal of Atmospheric Environment
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    • v.6 no.2
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    • pp.118-126
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    • 2012
  • To investigate the effect of aircraft traffic emissions on soil pollution, metal levels were analyzed for 8 metals (Fe, Cr, Pb, Zn, Cu, Ni, Mn and Cd) from the vicinity of the Indira Gandhi International (IGI) airport in Delhi, India. The texture of the airport soil was observed to be sandy. Among the metals, Cd showed minimum concentration ($2.07{\mu}g\;g^{-1}$), while Fe showed maximum concentration ($4379{\mu}g\;g^{-1}$). The highest metal accumulation was observed at the landing site. Significant correlations were observed between metals and different textures (sand, silt, and clay) as well as with organic carbon (OC). The results indicate that grain size play a major role in OC retention in soil and subsequently helps in adsorption of metals in soil. M$\ddot{u}$ller's geoaccumulation index (I-geo) showed that airport soil was contaminated due to Cd and Pb with the pollution class 2 and 1, respectively. Pollution load index of the airport site was 1.34-3 times higher than the background site. The results of factor analysis suggested that source of the soil metal is mainly from natural weathering of soil, aircraft exhaust, and automobile exhaust from near by area. With respect to Dutch target values, the airport soils showed ~3 times higher Cd concentration. The study highlighted the future risk of enhanced metal pollution with respect to Cd and Pb due to aircraft trafficking.

Atomic layer chemical vapor deposition of Zr $O_2$-based dielectric films: Nanostructure and nanochemistry

  • Dey, S.K.
    • Electrical & Electronic Materials
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    • v.16 no.9
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    • pp.64.2-65
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    • 2003
  • A 4 nm layer of ZrOx (targeted x-2) was deposited on an interfacial layer(IL) of native oxide (SiO, t∼1.2 nm) surface on 200 mm Si wafers by a manufacturable atomic layer chemical vapor deposition technique at 30$0^{\circ}C$. Some as-deposited layers were subjected to a post-deposition, rapid thermal annealing at $700^{\circ}C$ for 5 min in flowing oxygen at atmospheric pressure. The experimental x-ray diffraction, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and high-resolution parallel electron energy loss spectroscopy results showed that a multiphase and heterogeneous structure evolved, which we call the Zr-O/IL/Si stack. The as-deposited Zr-O layer was amorphous $ZrO_2$-rich Zr silicate containing about 15% by volume of embedded $ZrO_2$ nanocrystals, which transformed to a glass nanoceramic (with over 90% by volume of predominantly tetragonal-$ZrO_2$(t-$ZrO_2$) and monoclinic-$ZrO_2$(m-$ZrO_2$) nanocrystals) upon annealing. The formation of disordered amorphous regions within some of the nanocrystals, as well as crystalline regions with defects, probably gave rise to lattice strains and deformations. The interfacial layer (IL) was partitioned into an upper Si $o_2$-rich Zr silicate and the lower $SiO_{x}$. The latter was sub-toichiometric and the average oxidation state increased from Si0.86$^{+}$ in $SiO_{0.43}$ (as-deposited) to Si1.32$^{+}$ in $SiO_{0.66}$ (annealed). This high oxygen deficiency in $SiO_{x}$ indicative of the low mobility of oxidizing specie in the Zr-O layer. The stacks were characterized for their dielectric properties in the Pt/{Zr-O/IL}/Si metal oxide-semiconductor capacitor(MOSCAP) configuration. The measured equivalent oxide thickness (EOT) was not consistent with the calculated EOT using a bilayer model of $ZrO_2$ and $SiO_2$, and the capacitance in accumulation (and therefore, EOT and kZr-O) was frequency dispersive, trends well documented in literature. This behavior is qualitatively explained in terms of the multi-layer nanostructure and nanochemistry that evolves.ves.ves.

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Studies on the Absorption and Accumulation of Fenitrothion in Rice Plants (수도에 살포한 Fenitrothion의 부위별 잔류에 관한 연구)

  • Park Seung Heui
    • Korean journal of applied entomology
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    • v.14 no.1 s.22
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    • pp.29-33
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    • 1975
  • The experiment It·as conducted to find out the distribution of fenitrothion in rice plants at the preheading stage and its residue in harvested grains. The results obtained were as follows; 1. Distribution of fenitrothion in rice plants were measured 15.32 ppm attached to the leaf surface immediately after spray and 6.73 ppm was penetrated into tissues after 24 hours. 2. Residual amounts of fenitrothion in rice grains was 0.04 ppm at chaff and 0.01 ppm at unpolished rice, respectively.

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Quasi Static Fatigue Analysis of Spot Welding Component considering Change of Stiffness (강성변화를 고려한 점용접부의 준정적피로해석)

  • Lee, Dong-Cheol;Jeong, Heon Sul;Kang, Ki-Weon
    • Journal of the Korea Convergence Society
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    • v.4 no.2
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    • pp.21-27
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    • 2013
  • Spot welding is automation of assembly process, without increasing the vehicle weight and economy, there is a fuel economy improvement of motor vehicles and to widely used in the automotive industry. But By irregular load from the road surface while at the vehicle is running, stress concentration occurs in the weld point, fatigue failure occurs frequently. Considering change of stiffness is the essential fatigue life of the evaluation spot weld. In this paper, by performing a linear static analysis was to understand the vulnerable part. Acquire to the fatigue properties of the spot weld, take the load history of the three levels in the time domain, was performed by setting as a condition of quasi-static fatigue analysis. and Fatigue life prediction method of the spot weld was by applying the method according to the fatigue damage accumulation and the conventional method was compared analyzed with the results shown.

Effects ofRelative Humidity on Russet Occurrence in Whangkeumbae Pear (Pyrus pyrifolia Nakai cv,) (상대습도가 황금배(pyrus pyrifolia Nakai cv.) 동녹발생에 미치는 영향)

  • 조일환;우영회;최장전;한점화;서흥수
    • Journal of Bio-Environment Control
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    • v.11 no.1
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    • pp.1-4
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    • 2002
  • The occurrence rate of russet in 'Whangkeumbae' pear showed significant difference by years because the russet occurrence is greatly affected by the amount of rainfall. This study was conducted to analyse the relationship between rainfall and russet occurrence by artificial treatment of high humidity. Under high relative humidity condition, stomatal resistance decreased and average fruit weight was higher since the increased net photosynthesis rate accumulation accelerated fruit growth. The russet occurrence began on July 25, when the growth speed of fruit weight and fruit surface is the most fast. Russet occurrence rate was higher in high relative humidity condition because the fruit growth was accelerated. Since the fruit calcium concentration change is extreme in late July, it is assumed that the deceased calcium content is related to the occurrence of russet in 'Whangkeumbae' pear, When the high relative humidity condition is maintained after rainfall, the amount of net photosynthesis rate increase and fruit growth is accelerated. Therefore, the unbalance in the amounts of transferred photosynthesis assimilation product, water and mineral elements would be one of the reasons for the russet occurrence in 'Whangkeumbae' pear.

Drug research and development tend to hyperlipidemia (이상지질혈증과 치료제 연구개발 경향)

  • Seol, In-Chan
    • Journal of Haehwa Medicine
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    • v.18 no.2
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    • pp.1-12
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    • 2009
  • Most of the cholesterol is synthesized by liver in the body while about one of third is taken via dietary. The main functions of cholesterol is to protect membranes in cell surface, avoid the arterial bleeding by hypertension, and prolong the life of erythrocytes, and so on. However, overload of cholesterol leads to arteriosclerosis associated with leading death cause. Lack of physical activity, emotional and environmental stress, and low intake of protein or vitamin E induce the unbalance between HDL- and LDL-cholesterol so become a basis of ischemic disorders in heart, brain and elsewhere in the body. So far, four major classes of medications for hyperlipidemia are HMG-CoA reductase inhibitors (statins), bile acid sequestrants, nicotinic acid, and fibric acids. The statins can lower LDL and levels triglyceride, but may induce myopathy and an elevation of liver enzyme levels. The bile acid sequestrants lower LDL levels and raise HDL levels with no effect on triglyceride levels but side effects of gastrointestinal (GI) distress, constipation, and a decrease in the absorption of other drugs. Nicotinic acid and fibric acids lower LDL and triglyceride levels with showing flushing, hyperglycemia, hyperuricemia, GI distress, and hepatotoxicity dyspepsia, gallstones, myopathy, and unexplained noncardiac death as adverse effects. Above western drugs lower cholesterol by 15 to 30% while all have notable adverse effects. In traditional medicine, hyperlipidemia is regarded as retention of phlegm and fluid disease. Etiology and pathogenesis of hyperlipidemia is basically based on Spleen-Deficiency and Phlegm-Stagnation, accumulation and stasis of -heat, and Qi & blood stagnation induced by Phlegm-damp, water-dampness, and blood stasis. Thereby, strengthening Spleen and dissolving Phlegm, clearing away heat and diuresis, and supplementing Qi and activating blood circulation are commonly used therapeutic methods for hyperlipidemia. The traditional herbal medicine, have been used for patients with CVA, hypertension or hyperlipidemia in Oriental hospital or Oriental clinic. The lock and key theory is used to develop most of western medicine, however many diseases are caused by mixed factors in body-complex system. We expect that Oriental pharmacological theory could be newborn as a novel drug showing high advantage of blood levels of lipidsand QOL of performance without side effects.

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The Effects of Jinmu-tang on Mesangial Cell Proliferation, Fibronectin Synthesis and Expression of ICAM-1, $\beta$ 1-Integrin, MHC-Class II (진무탕이 배양 인체 메산지움 세포증식과 기질 침착에 미치는 영향)

  • 안영민;안세영;두호경;이태원;박재경
    • The Journal of Korean Medicine
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    • v.21 no.3
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    • pp.40-50
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    • 2000
  • Objectives : The progression of renal disease can be identified as a glomerulosclerosis by histological examination, and the basic mechanism of glomerulosclerosis is mesangial cell proliferation and mesangial matrix accumulation. ICAM-1, ${\beta}1-integrin$ and MHC-class II are known to attribute to the progression of glomerulosclerosis. They mediate cell-cell or cell-matrix interactions and are expressed in response to injury and inflammation. Up to now, there have been few satisfactory regimens to treat glomerular diseases except minimal change nephrotic syndrome, which can be improved by steroid therapy. Studies were performed in order to investigate whether Jinmu-tang has suppressive effects on some factors associated with the progression of glomerular disease, mesangial cell proliferation, fibronectin synthesis, ICAM-1, ${\beta}1-integrin$ and MHC-class II expression. Methods : Studies were performed with the method of surface enzyme immunoassays or flow cytometry after addition of peripheral blood mononuclear cells(PBMC) supernatants treated with Jinmu-tang, using the cultured human mesangial cells. Results : 1. The suppressive effect of Jinmu-tang on mesangial cell proliferation was higher than that of hydrocortisone. 2. Jinmu-tang has some suppressive effects on fibronectin synthesis, ICAM-1, expression, ${\beta}1-integrin$ expression and MHC-class II expression of mesangial cells, but was lower than hydrocortisone. Conclusions : Jinmu-tang generally shows some immunosuppressive effects. We carefully suggest that the above prescription may be applied to prevent the progression of renal disease or can be used as an adjuvant of or a substitute for steroid therapy.

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Fates and Removals of Micropollutants in Drinking Water Treatment (정수처리 과정에서의 미량오염물질의 거동 및 제거 특성)

  • Nam, Seung-Woo;Zoh, Kyung-Duk
    • Journal of Environmental Health Sciences
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    • v.39 no.5
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    • pp.391-407
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    • 2013
  • Micropollutants emerge in surface water through untreated discharge from sewage and wastewater treatment plants (STPs and WWTPs). Most micropollutants resist the conventional systems in place at water treatment plants (WTPs) and survive the production of tap water. In particular, pharmaceuticals and endocrine disruptors (ECDs) are micropollutants frequently detected in drinking water. In this review, we summarized the distribution of micropollutants at WTPs and also scrutinized the effectiveness and mechanisms for their removal at each stage of drinking water production. Micropollutants demonstrated clear concentrations in the final effluents of WTPs. Although chronic exposure to micropollutants in drinking water has unclear adverse effects on humans, peer reviews have argued that continuous accumulation in water environments and inappropriate removal at WTPs has the potential to eventually affect human health. Among the available removal mechanisms for micropollutants at WTPs, coagulation alone is unlikely to eliminate the pollutants, but ionized compounds can be adsorbed to natural particles (e.g. clay and colloidal particles) and metal salts in coagulants. Hydrophobicities of micropollutants are a critical factor in adsorption removal using activated carbon. Disinfection can reduce contaminants through oxidation by disinfectants (e.g. ozone, chlorine and ultraviolet light), but unidentified toxic byproducts may result from such treatments. Overall, the persistence of micropollutants in a treatment system is based on the physico-chemical properties of chemicals and the operating conditions of the processes involved. Therefore, monitoring of WTPs and effective elimination process studies for pharmaceuticals and ECDs are required to control micropollutant contamination of drinking water.