• BMB Reports
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• v.31 no.2
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• pp.161-169
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• 1998

TThe reactive oxygen species oxidatively modify the biological macromolecules, including proteins, lipids, and nucleic acids. Iron- and heme-mediated Fenton-like reactions produce different pro-oxidants. However, these reactive products have not been clearly characterized. We examined the nature of the oxidizing species from the different iron sources by measuring oxidative protein modification and spectroscopic study. Hemoglobin (Hb) and methemoglobin (metHb) were oxidatively modified in $O{\array-\\\dot{2}}$ and $H_{2}O_{2}$ generating systems. Globin and bovine serum albumin (BSA) were also modified by iron, iron-EDTA, hematin, and Hb in an $O{\array-\\\dot{2}}$ generating system. In a $H_{2}O_{2}$ generating system, the iron- and iron-EDTA-mediated protein modifications were markedly reduced while the Hb-and hematin-mediated modifications were slightly increased. In the $O{\array-\\\dot{2}}$ generating system, the iron- and iron-EDTA-mediated protein modifications were strongly inhibited by superoxide dismutase (SOD) or catalase, but heme- and Hb-mediated protein modifications were inhibited only by catalase and slightly increased by SOD. Mannitol, 5,5-dimethyl-l-pyrroline-N-oxide (DMPO), deoxyribose, and thiourea inhibited the iron-EDTA-mediated protein modification. Mannitol and DMPO, however, did not exhibit significant inhibition in the hematin-mediated modification. Desferrioxamine (DFO) inhibited protein modification mediated by iron, but cyanide and azide did not, while the hematin-mediated protein modification was inhibited by cyanide and azide, but not significantly by DFO. The protein-modified products by iron and heme were different. ESR and UV-visible spectroscopy detected the DMPO spin adduct of the hydroxyl radical and ferryl ion generated from iron-EDTA and metHb, respectively. These results led us to conclude that the main oxidizing species are hydroxyl radical in the iron-EDTA type and the ferry I ion in the hematin type, the latter being more effective for protein modification.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.589-601
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• 2023

Purpose: Baicalein, a natural flavone found in herbs, exhibits diverse biological activities. Nonalcoholic steatohepatitis (NASH) is an irreversible condition often associated with a poor prognosis. This study aimed to evaluate the effects of baicalein on the development of NASH in mice. Methods: Male C57BL/6J mice were randomly divided into four groups. Three groups were fed a methionine-choline-deficient (MCD) diet to induce NASH and were simultaneously treated with baicalein (at doses of 50 and 100 mg/kg) or vehicle only (sodium carboxymethylcellulose) through oral gavage for 4 weeks. The control group was fed a methionine-choline-sufficient (MCS) diet without the administration of baicalein. Results: The baicalein treatment significantly reduced serum levels of alanine aminotransferase and aspartate aminotransferase, suggestive of reduced liver damage. Histological analysis revealed a marked decrease in nonalcoholic fatty liver activity scores induced by the MCD diet in the mice. Similarly, baicalein treatment at both doses significantly attenuated the degree of hepatic fibrosis, as examined by Sirius red staining, and hepatocellular death, as examined by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Baicalein treatment attenuated MCD-diet-induced lipid peroxidation, as evidenced by lower levels of hepatic malondialdehyde and 4-hydroxynonenal, demonstrating a reduction in oxidative stress resulting from lipid peroxidation. Moreover, baicalein treatment suppressed hepatic protein levels of 12-lipoxygenase (12-Lox) induced by the MCD diet. In contrast, baicalein enhanced the activities of antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. Additionally, baicalein treatment significantly reduced hepatic non-heme iron concentrations and hepatic ferritin protein levels in mice fed an MCD diet. Conclusion: To summarize, baicalein treatment suppresses hepatic lipid peroxidation, 12-Lox expression, and iron accumulation, all of which are associated with the attenuation of NASH progression.

• Research in Plant Disease
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• v.29 no.1
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• pp.82-87
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• 2023

Exogenous ferrous chloride (FeCl₂) suppressed in vitro growth of Ralstonia pseudosolanacearum, causing bacteria for tomato bacterial wilt. More than 50 μM of FeCl₂ reduced the in vitro bacterial growth in dosedependent manners. Two to 200 μM of FeCl₂ did not affect the fresh weight of detached tomato leaves at 3 and 5 days after the petiole dipping without the bacterial inoculation. The bacterial wilt of the detached tomato leaves was evaluated by inoculating two different inoculum densities of R. pseudosolanacearum (10⁵ and 10⁷ cfu/ml) in the presence of FeCl₂. Bacterial wilt in the detached leaves by 10⁵ cfu/ml was efficiently attenuated by 10-200 μM of FeCl₂ at 3 and 5 days post-inoculation (dpi), but bacterial wilt by 10⁷ cfu/ml was only reduced by 200 μM of FeCl₂ at 3 and 5 dpi. These results suggest that iron nutrients can be included in the integrated disease management of tomato bacterial wilt.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.21-29
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• 2001

An experiment was conducted with twenty crossbred male lambs to assess the effect of cotton (Gossypium) seed meal (CSM) on blood constituents and immunity. Lambs were randomly assigned to a reference diet (30% deoiled peanut meal, DPNM) and four test diets containing 40% of either raw, 45 minutes cooked, 1% $Ca(OH)_2$ and iron (1 free gossy-pol, FG : 0.3 Fe) treated CSM (replacing approximately 50%, reference concentrate mixture). These isonitrogenous and isocaloric concentrate mixtures were fed to meet 80% of protein requirements (NRC, 1985) along with ad lib maize hay for 180 days. Blood was collected at 60, 120 and 180 days post feeding. The lambs were sensitized with Brucella abortus S99 antigen after 140 days and were subjected to ELISA and delayed type hypersensitivity. Blood haemoglobin, erythrocyte count, leucocyte count, total protein, total albumin, total globulin, urea, creatinine concentration and aspartate aminotransferase activity in lambs fed on raw or processed CSM were comparable to the values of reference lambs. The higher (p<0.01) blood glucose levels observed in CSM fed lambs at 60 days of feeding was latter reduced to the levels comparable with those on reference diet at 120 and 180 days of feeding. The alanine amino transferase activity was lower in lambs fed raw and cooked CSM containing diets at 120 and 180 days of feeding. A marginal increase in serum iron and alkaline posphatase activity was observed in iron treated group and raw CSM fed lambs, respectively. The humoral immune response and DTH reactivity was lower (p<0.05) in lambs fed raw CSM (consuming 302.83 mg FG/day). Cooking, $Ca(OH)_2$ and iron treatment of raw CSM showed a positive response in alleviating the suppression of immune response owing to the reduced consumption of FG by 40.19, 17.40% and 26.73%, respectively in these diets. The present study thus indicated that consumption of 40% raw CSM (302.83 mg FG/day) though did not affect majority of the haematological and blood biochemical parameters, but markedly suppressed the immune mechanism of lambs.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.83-91
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• 2006

Reduction kinetics and the behaviour of intermediate of three high explosives (HMX, RDX, and TNT) were studies in batch reactors using nano- or micro- size zero valent iron(nZVI or mZVI) as reducing agent. The kinetic constants normalized by the mass of iron ($k_M$) or by the surface area ($k_{SA}$) were measured and compared along with the changes in the concentrations of intermediates. Results showed that $k_M$ and $k_{SA}$ values were not suitable to fully explain the behaviour of mother compounds and reduced intermediates in the batch reactor. The concentrations of initial explosives degradation products, such as nitroso-RDXs, nitroso-HMXs, and hydroxylamino-TNTs, were higher in mZVI treated reactor than in nZVI treated reactor, whereas more reduced polar intermediates such as TAT were accumulated in the nZVI reactor. Therefore, a new parameter, which accounted for the intermediates reduction, needs to be developed.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.287-294
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• 1995

This study demonstrates the influence of environmental conditions, other than iron, on pyoverdin production by fluorescent Pseudomosonas. In slightly acidic pH conditions(pH 6), cell yield was reduced while the siderophore production per cell yield was increased. The optimum temperatures for the siderophore production and cell yield was $19^{\circ}C$ and $28^{\circ}C$ for 7NSK2 and $12^{\circ}C$ and $19^{\circ}C$ for ANP15. The carbon and nitrogen balance showed that at low C : N ratio of the growth medium (higher nitrogen concentration), both cell yield and siderophore production was reduced. Use of different carbon sources revealed that citrate as a carbon source facilitated iron uptake and resulted in a significant reduction in siderophore production. However, at the late exponential phase, the iron content in the cell biomass was not significantly different from those grown in glucose or succinate. From these results it can be suggested that the environmental factors other than iron may also influence siderophore production by fluorescent pseudomonas.

• Resources Recycling
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• v.28 no.1
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• pp.47-54
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• 2019

In this study, the wastes were used as fuels for direct reduction iron (DRI) production to reduce production cost and recycle the wastes. We examined the effects of wastes on the reduction behavior of DRI manufacture and the possibility of using wastes as auxiliary fuels. The proximate and Ultimate analysis were carried out to confirm the properties of wastes as fuels, and high-quality reduced irons were fabricated by using the waste as an auxiliary fuel. The metallization of reduced irons increased as the calorific value increase of auxiliary fuel. Especially, the reduced irons fabricated from the waste tires and vinyl plastics which had high heat energy and volatile matters showed higher metallization than the others. The high calorific value and volatility of waste were significant properties as fuel. The high quality DRI could be fabricated with wastes as auxiliary fuels through optimization of reaction conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.73-77
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• 2002

The requirements for higher productivity call for high speed of the machine tool axes. Iron core type linear DC motor is growly accepted far a viable candidate of the high speed machine tool feed unit. LDM, however, has inherent disturbance force components: cogging and force ripple. These disturbance force directly affects tracking accuracy of the carrage and must be eliminated or reduced. Reducing motor ripple, this paper adapted the feed forward compensation method and neural network control. Experiments carried 7ut on the linear motor test setup show that this control methods is usable in order to reduce the motor ripple.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.2
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• pp.268-277
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• 1994

Current sensor using Hall device is an instrument of detecting a current by Hall effect. The existing current sensor is ordinarily worked by concentrating electromagnetism produced around the conducting wire turned iron core. The tiny curren, however, could not be accurately detected by the instrument owing to influence of residual magnetism exisisting in iron core, and the result of detecting is also somewhat on the large side. kAccordingly, We fabricated a new type of instrument minimizing the influence of residual magnetism existing in iron core and detected the tiny DC current accurately by taking advantage of magnetic modulation. The range of measuring DC current is 0[mA]-100[mA] and the maxiumm Linerity tolleance by the result of detecting current, can be reduced less than 3 percent.

• ETRI Journal
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• v.25 no.5
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• pp.412-417
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• 2003

Using a galvanostatic charge/discharge cycler and cyclic voltammetry, we investigated for the first time the electrochemical properties of iron-containing minerals, such as chalcophanite, diadochite, schwertmannite, laihuite, and tinticite, as electrode materials for lithium secondary batteries. Lithium insertion into the mineral diadochite showed a first discharge capacity of about 126 mAh/g at an average voltage of 3.0 V vs. $Li/Li^+$, accompanied by a reversible capacity of 110 mAh/g at the 60th cycle. When the cutoff potential was down to 1.25 V, the iron was further reduced, giving rise to a new plateau at 1.3 V. Although the others showed discharge plateaus at low potentials of less than 1.6 V, these results give an important clue for the development of new electrode materials.