• Title/Summary/Keyword: diffusion control reaction

Search Result 70, Processing Time 0.032 seconds

Mathematical Modeling for Leaching and dissolution of Solidified Radioactive Waste in a Geologic Reposiory (지하 처분장에서의 방사성폐기물 고화체의 용출 및 용해에 대한 수학적 모형 분석)

  • Kim, Chang-Lak;Park, Kwang-Sub;Cho, Chan-Hee;Kim, Jhinwung;Suh, In-Suk
    • Nuclear Engineering and Technology
    • /
    • v.20 no.2
    • /
    • pp.120-131
    • /
    • 1988
  • A souce term model describes mathematically the source of radionuclides as they begin slow migration and decay in deep groundwater. Various source term models based on mass-transfer analysis and measurement-based source term models are reviewed. Ganerally, two processes are involved in leaching or dissolution: (1) chemical reactions and (2) mass transfer by diffusion. The chemical reaction controls the dissolution rates only during the early stage of exposure to groundwater. The exterior-field mass transfer may control the long term dissolution rates from the waste solid in a geologic repository. Mass-transfer analyses re3y on detailed and careful application of the governing equations that describe the mechanistic processes of transport of material between and within phases. If used correctly, source term models based on mass-transfer theory are valuable and necessary tools for developing reliable predictions.

  • PDF

Hyperbaric oxygen therapy for the treatment of a crush injury of the hand: a case report

  • Neto, Pedro Henry;Ribeiro, Zamara Brandao;Pinho, Adriano Bastos;Almeida, Carlos Henrique Rodrigues de;Maranhao, Carlos Alberto de Albuquerque;Goncalves, Joaquim da Cunha Campos
    • Journal of Trauma and Injury
    • /
    • v.35 no.3
    • /
    • pp.209-214
    • /
    • 2022
  • We describe a case of hyperbaric oxygen therapy (HBOt) as an adjunct to treatment of a crush injury to the hand. A 34-year-old male paramedic was involved in a motor vehicle accident and admitted for diagnosis and surgical treatment. He sustained a crush injury to his right hand and presented with significant muscle damage, including multiple fractures and dislocations, an avulsion injury of the flexor tendons, and amputation of the distal phalanx of the little finger. He underwent reconstructive surgery and received HBOt over the following days. In the following 2 months, he lost the distal and middle phalanges of the little finger and recovered hand function. Posttraumatic compartment syndrome responds well to HBOt, which reduces edema and contributes to angiogenesis, as well as promoting the cascade of healing events. High-energy trauma causes massive cell destruction, and the blood supply is usually not sufficient to meet the oxygen demands of viable tissues. Hyperbaric oxygenation by diffusion through interstitial and cellular fluids increases tissue oxygenation to levels sufficient for the host's responses to injury to work and helps control the delayed inflammatory reaction. HBOt used as an adjunct to surgical treatment resulted in early healing and rehabilitation, accelerating functional recovery. The results suggest that adjunctive HBOt can be beneficial for the treatment of crush injuries of the hand, resulting in better functional outcomes and helping to avoid unnecessary amputations.

Comparison of Agar-gel Diffusion Test, Counterimmunoelectrophoresis and Enzyme-Linked Immunosorbent Assay in the sera of skin teat positives for paragonimiasis (간흡충 피내반응 양성자에 대한 Agar-gel Diffusion, Counterimmunoelectrophoresis 및 Enzyme-Linked Immunosorbent Assay의 비교)

  • 이옥란;최원영
    • Parasites, Hosts and Diseases
    • /
    • v.21 no.2
    • /
    • pp.270-280
    • /
    • 1983
  • Agar-gel Diffusion test (AGD), Counterimmunoelectrophoresis(CIEP) and Enzyme-Linked Immunosorbent Assay(ELISA) were examined with the sera of skin test positives for paragonimiasis. The crude antigen (Paragcnimus whole worm extracts: protein concentration, 7.56mg/m1) and human sera were used in AGD and CIEP. And in ELISA test, diluted antigen with 1:40, 000 of crude antigen and diluted sera with 1:100, 1:200 were used in the test. The positive identical ratio between AGD and CIEP reactions is 985 and negative identical ratio is 100%. One or three precipitin bands are observed in AGD. One to seven precipitin bands are also revealed in CIEP. Especially, deeply stained bands are observed in CIEP than those of AGD. The positive identical ratios between AGD and ELISA tests are 96% in 1:100 diluted sera, and 94% in 1:200 diluted sera. But the negative identical ratios between AGD and ELISA tests are 97% and 99% respectively in 1:100 and 1:200 diluted sera. The positive identical ratios between CIEP and ELIEA tests are 98% and 96% respectively in 1:100 and 1:200 diluted sera, but also 97% and 99% in 1:100 and 1:200. Control sera, such as clonorchiasis, amoebiasis and toxoplasmcsis, revealed all negatives with Paragonimus antigen in AGD, CIEP and ELISA tests. By above results, ELISA was mcst sensitive, next CIEP and AGD, But AGD test apprars to be more useful when used to crude antigen without cross rfacticn with other parasitic infections. CIEP test is basically equal in terms of precipitin reaction, but CIEP is able to be detected more sensitively and rapidly though less simple in handiwork than AGD. Consequently, three methods for inlmunological tests of paragonimiasis have gccd correlations with one another. Also, each of these has both merits and demerits in iymunolcgical test for paragonimiasis. But the ELISA test was proved to be the most sensitive and convenient tool for mass screening test, especially in cacti of using purified antigen.

  • PDF

Biogeochemical Effects of Hydrogen Gas on the Behaviors of Adsorption and Precipitation of Groundwater-Dissolved Uranium (지하수 용존 우라늄의 수착 및 침전 거동에서 수소 가스의 생지화학적 영향)

  • Lee, Seung Yeop;Lee, Jae Kwang;Seo, Hyo-Jin;Baik, Min Hoon
    • Economic and Environmental Geology
    • /
    • v.51 no.2
    • /
    • pp.77-85
    • /
    • 2018
  • There would be a possibility of uranium contamination around the nuclear power plants and the underground waste disposal sites, where the uranium could further migrate and diffuse to some distant places by groundwater. It is necessary to understand the biogeochemical behaviors of uranium in underground environments to effectively control the migration and diffusion of uranium. In general, various kinds of microbes are living in soils and geological media where the activity of microbes may be closely connected with the redox reaction of nuclides resulting in the changes of their solubility. We investigated the adsorption and precipitation behaviors of dissolved uranium on some solid materials using hydrogen gas as an electron donor instead of organic matters. Although the effect of hydrogen gas did not appear in a batch experiment that used granite as a solid material, there occurred a reduction of uranium concentration by 5~8% due to hydrogen in an experiment using bentonite. This result indicates that some indigenous bacteria in the bentonite that have utilized hydrogen as the electron donor affected the behavior (reduction) of uranium. In addition, the bentonite bacteria have showed their strong tolerance against a given high temperature and radioactivity of a specific waste environment, suggesting that the nuclear-biogeochemical reaction may be one of main mechanisms if the natural bentonite is used as a buffer material for the disposal site in the future.

Chromium Speciation in Cr(III) Oxidation by Mn-Oxides: Relation to the Oxidation Mechanism (망간 산화물에 의한 3가 크롬의 산화반응에 미치는 크롬 화학종들의 영향)

  • Chung, Jong-Bae
    • Applied Biological Chemistry
    • /
    • v.41 no.1
    • /
    • pp.89-94
    • /
    • 1998
  • Various Mn-oxides can oxidize Cr(III) to Cr(VI). Behaviors of chromium species in the oxidation system, especially on the oxide surface, are expected to control the reaction. During Cr(III) oxidation by birnessite and pyrolusite, Cr species in the reaction system were determined to elucidate their effects on the oxidation. Capacities of Cr oxidation of the two Mn-oxides were quite different. Solution pH and initial Cr(III) concentration also had significant effects on the Cr(III) oxidation by Mn-oxides. Chromium oxidation by pyrolusite was less than 5% of the oxidation by birnessite. The high crystallinity of pyrolusite could be one of the reasons and the difficulty of Cr (III) diffusion to the positive pyrolusite surface and Cr(VI) and Cr(III) adsorption seems to be other controlling factors. At pH 3, adsorption or precipitation of Cr species on the surface of birnessite were not found. Small amount of Cr(VI) adsorption was found on the surface of pyrolusite, but arty Cr precipitation on the oxide surface was not found. Therefore Cr(III) oxidation at pH 3 seems to be controlled mainly by the characteristics of Mn-oxides. Chromiun oxidation by Mn-oxides is thermodynamically more favorable at higher solution pH. However as solution pH increased Cr oxidation by birnessite was significantly inhibited. For Cr oxidation by pyrolusite, as pH increased the oxidation increased, but as Cr(III) addition increased the reaction was inhibited. Under these conditions some unidentified fraction of Cr species was found and this fraction is considered to be Cr(III) precipitation an the oxide surface. Chromium(III) precipitation on the oxide surface seems to play an important role in limiting Cr(III) oxidation by armoring the reaction surface on Mn-oxides as well as lowering Cr(III) concentration available for the oxidation reaction.

  • PDF

Anti-Oral Microbial Activity and Anti-Inflammatory Effects of Rosmarinic Acid in Lipopolysaccharide-Stimulated MC3T3-E1 Osteoblastic Cells on a Titanium Surface

  • Jeong, Moon-Jin;Lim, Do-Seon;Heo, Kyungwon;Jeong, Soon-Jeong
    • Journal of dental hygiene science
    • /
    • v.20 no.4
    • /
    • pp.221-229
    • /
    • 2020
  • Background: The purpose of this study was to investigate the anti-oral microbial activity and anti-inflammatory effects of rosmarinic acid (RA) in lipopolysaccharide (LPS)-stimulated MC3T3-E1 osteoblastic cells on a titanium (Ti) surface during osseointegration, and to confirm the possibility of using RA as a safe natural substance for the control of peri-implantitis (PI) in Ti-based dental implants. Methods: A disk diffusion test was conducted to confirm the antimicrobial activity of RA against oral microorganisms. In order to confirm the anti-inflammatory effects of RA, inflammatory conditions were induced with 100 ng/ml of LPS in MC3T3-E1 osteoblastic cells on the Ti surface treated with or without 14 ㎍/ml of RA. The production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated MC3T3-E1 osteoblastic cells on the Ti surface was confirmed using an NO assay kit and PGE2 enzyme-linked immunosorbent assay kit. Reverse transcription polymerase chain reaction and western blot analysis were performed to confirm the expression of interleukin (IL)-1β and tumor necrosis factor (TNF)-α in total RNA and protein. Results: RA showed weak antimicrobial effects against Streptococcus mutans and Escherichia coli, but no antimicrobial activity against the bacteria Aggregatibacter actinomycetemcomitans and the fungus Candida albicans. RA reduced the production of pro-inflammatory mediators, NO and PGE2, and proinflammatory cytokines, TNF-α and IL-1β, in LPS-stimulated MC3T3-E1 osteoblastic cells on the Ti surface at the protein and mRNA levels. Conclusion: RA not only has anti-oral microbial activity, but also anti-inflammatory effects in LPS-stimulated MC3T3-E1 osteoblasts on the Ti surface, therefore, it can be used as a safe functional substance derived from plants for the prevention and control of PI for successful Ti-based implants.

Immunochemical Studies for the Characterization of Purified $(Na^+,\;K^+)-ATPase$ and Its Subunits with a Special Reference of Their Effect on Monovalent Cation Transport in Reconstituted $(Na^+,\;K^+)-ATPase$ Vesicles

  • Rhee, H.M.;Hokin, L.E.
    • The Korean Journal of Pharmacology
    • /
    • v.26 no.1
    • /
    • pp.35-49
    • /
    • 1990
  • A highly purified $(Na^+,\;K^+)-ATPase$ from the rectal gland of Squalus acanthias and from the electric organ of Electrophorus electricus has been used to raise antibodies in rabbits. The 97,000 dalton catalytic subunit and glycoprotein derived from the rectal gland of spiny shark were also used as antigens. The two $(Na^+,\;K^+)-ATPase$ holoenzymes and the two shark subunits were antigenic. In Ouchterlony double diffusion experiments, these antibodies formed precipitation bands with their antigens. Antibodies prepared against the two subunits of shark holoenzyme also formed precipitation bands with their antigens and shark holoenzyme, but not with eel holoenzyme. These observations are in good agreement with inhibitory effect of these antibodies on the catalytic activity of $(Na^+,\;K^+)-ATPase$ both from the shark and the eel, since there is very little cross-reaction between the shark anticatalytic subunit antibodies and the eel holoenzyme. The maximum antibodies titer of the anticatalytic subunit antibodies is found to be 6 weeks after the initial single exposure to this antigen. Multiple injections of the antigen increased the antibody titer. However, the time required to produce the maximum antibody titer was approximately the same. These antibodies also inhibit catalytic activity of $(Na^+,\;K^+)-ATPase$ vesicles reconstituted by a slow dialysis of cholate after solubilization of the enzyme in a presonicated mixture of cholate and phospholipid. In these reconstituted $(Na^+,\;K^+)-ATPase$ vesicles, effects of these antibodies on the fluxes of $Na^+$, $Rb^+$, and $K^+$ were investigated. Control or preimmune serum had no effect on the influx of $^{22}Na^+$ or the efflux of $^{86}Rb^+$. Immunized sera against the shark $(Na^+,\;K^+)-ATPase$ holoenzyme, its glycoprotein or catalytic subunit did inhibit the influx of $^{22}Na^+$ and the efflux of $^{86}Rb^+$. It was also demonstrated that these antibodies inhibit the coupled counter-transport of $Na^+$ and $K^+$ as studied by means of dual labeling experiments. However, this inhibitory effect of the antibodies on transport of ions in the $(Na^+,\;K^+)-ATPase$ vesicles is manifested only on the portion of energy and temperature dependent alkali metal fluxes, not on the portion of ATP and ouabain insensitive ion movement. Simultaneous determination of effects of the antibodies on ion fluxes and vesicular catalytic activity indicates that an inhibition of active ion transport in reconstituted $(Na^+,\;K^+)-ATPase$ vesicles appears to be due to the inhibitory action of the antibodies on the enzymatic activity of $(Na^+,\;K^+)-ATPase$ molecules incorporated in the vesicles. These findings that the inhibitory effects of the antibodies specific to $(Na^+,\;K^+)-ATPase$ or to its subunits on ATP and temperature sensitive monovalent cation transport in parallel with the inhibitory effect of vesicular catalytic activity by these antibodies provide direct evidence that $(Na^+,\;K^+)-ATPase$ is the molecular machinery of active cation transport in this reconstituted $(Na^+,\;K^+)-ATPase$ vesicular system.

  • PDF

Changes of Serum antibody Levels by Indirect Hemagglutination Test after Treatment in Clonorchiasis (IHA(Indirect hemagglutination test)를 이용한 간흡충증(肝吸虫症)의 면역혈청학적(免疫血淸學的) 진단(診斷)에 관한 연구(硏究) -ELISA법과의 비교(比較) 및 치료(治療) 전후(前後) 의 혈청항체가(血淸抗體價) 변동(變動)에 관하여-)

  • Joo, Kyoung-Hwan;Kim, Jong-Seong;Chung, Myung-Sook;Rim, Han-Jong
    • Journal of agricultural medicine and community health
    • /
    • v.12 no.1
    • /
    • pp.117-123
    • /
    • 1987
  • Detection of IgG antibody in clonorchiasis has been accomplished through various serodiagnostic procedure including complement fixation test, gel diffusion test, indirect fluorescent antibody test, indirect hemagglutination test etc. In this report enzyme immunoassay (ELISA) and indirect hemagglutination test (IHA) were used to determine IgG serum antibody levels before and after therapy with praziquantel. Briefly, sera from 62 cases of confirmed human clonorchiasis were examined before and after treatment with praziquantel. Among 62 cases treated 25 cases were categorized as completely cured groups by formalin-ether and careful examination of 4 cellophane thick smered slides at 18 months after treatment. The sera of 25 cases of cured groups were examined again by ELISA and IHA, and com-pared to the previous data. The results obtained were as follows; 1) Sensitivity of IHA test was 83.6% when cut-off titer of 1:8 was applied. No sera obtained from 10 normal healthy control showed positive reaction. 2) Twenty cases (80.0%) out of 25 cured one showed negative results by IHA at 18 months after treatment. 3) Although 5 cases showed positive titer even 18 months after treatment 3 cases of them showed decreased antibody titer. However 2 cases did not show any response. 4) Even though almost all cases showed de- creased ELISA value, only 11 cases (44.0%) out of 25 patients showed negative results by ELISA at 18 months after treatment. In conclusion, it is suggested that, while IgG ELISA for detecting long persisting antibody was more sensitive than IHA, IHA results more conclusively indicated effective treatment in clonorchiasis by negative conversion than did the results of ELISA.

  • PDF

Some Properties of an Isolate of Peanut stunt virus Isolated from White Clover (Trifolium repens L.) (토끼풀에서 분리한 Peanut stunt virus의 성질)

  • Jung, Goo-Ho;Jeon, Yong-Woon;Choi, Jang-Kyung;Hong, Jin-Sung;Ryu, Ki-Hyun;Lee, Sang-Yong
    • Research in Plant Disease
    • /
    • v.14 no.1
    • /
    • pp.71-75
    • /
    • 2008
  • An isolate of Peanut stunt virus (PSV), named as Tr-PSV, was isolated from white clover (Trifolium repens L) showing mosaic symptom. Tr-PSV systemically infected all plants tested in the Nicotiana spp. and induced local lesions on inoculated leaves of Chenopodium amaranticolor. However, Tr-PSV induced typical mosaic symptoms as ER-PSV on Vigna unguiculata 5 to 6 days after inoculation, while Fny-CMV used as a control virus of Cucumovirus produced local lesions on inoculated leaves. In dsRNA analysis, Tr-PSV consisted of four dsRNAs, but satellite RNA was not detected. The cDNA of coat protein gene of Tr-PSV was amplified by RT-PCR using a Cucumovirus-specific single pair primers that designed to amplify a DNA fragment of approximately 950 bp. By restriction mapping analysis using RFLP of the RT-PCR products and by serological properties of gel diffusion test, Tr-PSV belongs to a typical member of PSV subgroup I. This is the first report on the occurrence of PSV in white clover in Korea.

Evaluation of Antioxidant, Cytoprotective and Antimicrobial Properties of Polygoni multiflori Radix Extract, Fractions and Its Major Constituent (하수오 추출물, 분획물 및 주성분의 항산화, 세포 보호 및 항균 활성에 관한 평가)

  • Shin, Hyuk Soo;Kim, Minwoo;Song, Jerry;Lee, Junseok;Ha, Yoonjeong;Jeon, Young Hee;Kim, Ji Woong;Lee, Yun Ju;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.44 no.4
    • /
    • pp.407-417
    • /
    • 2018
  • In this study, the antioxidant, cytoprotective and antimicrobial activities of 50% ethanol extract of Polygoni multiflori Radix (PMR) and its ethyl acetate fraction were evaluated to confirm the applicability as a functional ingredient. The activities of the major constituent of PMR were verified and 2, 3, 5, 4′-tetrahydroxystilbene 2-O-${\beta}$-D-glucoside (THSG) was confirmed to be the main component of extract and fraction using HPLC-DAD, LC-EIS-MS analysis. The phenolic and THSG contents of the ethyl acetate fraction were 11.1- and 3.0-folds higher than those of the ethanol extract, respectively. As a result of the DPPH assay and that of luminol dependent chemiluminescence assay in $Fe^{3+}$-EDTA/H2O2 system. the ethylacetate fraction was superior to the ethanol extract in free radical and ROS scavenging activities. Especially, the ethyl acetate fraction and THSG exhibited the similar scavenging activity like L-ascorbic acid in ROS scavenging activity. The ethyl acetate fraction perceived the most potent cytoprotective effect against oxidative damage of erythrocytes induced by photosensitization reaction, followed by the ethanol fraction, THSG and that of (+)-${\alpha}$-tocopherol, which was used as a positive control. Antimicrobial activities were evaluated by disc diffusion and broth microdilution assay against S. aureus, E. coli, P. aeruginosa and C. albicans. In particular, the antibacterial activity of the extract and fraction against S. aureus was superior to that of methyl paraben. Taken together, our results suggest that PMR could be used as a natural ingredient for antioxidant, cytoprotective and antimicrobial activities.