• Resources Recycling
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• v.2 no.2
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• pp.16-21
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• 1993

This study was carried out to investigate the settling characteristics of Fe(II) and Fe(III) hydroxide precipitates formed by pH adjustment of aqueous solution to remove ferrous and ferric ion in waste water. The results obstained in this study are as fellows : The settling rate was effectively increased with increasing the pH values of aqueous solution regulated by CaO and with increasing the amount of flocculant, on the other hand, application of excess flocculants decreased the settling rate. It is desirable that the concentration of iron ion is kept under $10^{-2}$ mol/ㅣ because the settling rate was decreased with increasing the concentration of iron hydroxide precipitates.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.389-398
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• 1984

The effect of N forms ($NO_3{^-}-N$, $NH_4{^+}-N$) and concentrations (4, 8, $16meq/{\ell}$) which were changed at head formation stage on the tip-burn incidence of chinese cabbage was studied under the three levels (0, 8, 16 meq/l) of Ca. All of the plants grown on $NH_4{^+}-N$ showed the symptoms of tip-burn and low yields regardless of Ca levels. Roots of plants grown on $NH_4{^+}-N$ were severely damaged. The pH of the leachate from $NH_4{^+}-N$ pot was decreased to below pH 5. Plants which had been grown on $NH_4{^+}-N$ before the head formation stage, but changed to $NO_3{^-}-N$ were recovered from abnormal growth. But, the reverse showed the tip-burn symptoms. $NH_4{^+}-N$ treatments increased the T-N contents, but lowered K and Ca contents of inner leafblades. Icreased applications of Ca did not affect the T-N and K contents of the inner leafblades. $NH_4{^+}-N$ suppressed Ca translocation into the inner leaves from outer leaves after the head formation stage, but $NO_3{^-}-N$ accelarated it. Ca contents were much lower in leaves showing tip-burn symptoms than in healthy leaves. Internal rot which is a tip-burn symptom occuring after head formation were noted in plants applied with high concentration of $NO_3{^-}-N$ both before and after the head formation stage. Ca contents correlated well with the rates of Ca application, but there was no correlation between ca conents and internal rot incidence. Chinese cabbage tip-burn is not caused by Ca deficiency, as is commonly believed, but rather by the water stress (95% water contents in $NO_3{^-}$-fed plants, 91% in $NH_4{^+}$-fed plants) resulting from root damage caused by ammonium toxicity. Internal rot is also caused by excess applications of nitrogen, and is unaffected by calcium levels.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2057-2061
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• 2012

Backgrounds: Deficiency or excess of trace elements can induce body metabolic disorders and cellular growth disturbance, even mutation and cancerization. Since there are few studies of the effect of trace elements in bladder carcinoma in China, the aim of this study was thus to assess variation using a case control approach. Methods: To determine this, 81 patients with bladder carcinoma chosen as a study group and 130 healthy persons chosen as a control group were all assayed for urinary and serum trace elements (calcium [Ca], zinc [Zn], copper [Cu], selenium [Se]) using an atomic absorption spectrophotometer, and the results were analyzed by independent sample t tests. The correlative factors on questionnaires answered by all persons were analyzed by logistic regression. Results: The results showed urinary Ca, Zn and serum Cu levels of the study group to be significantly higher (P<0.05) than those of he control group. Serum Ca and Se levels of study group were significantly lower (P<0.05) than those of control group. Conclusion: There were higher urinary Zn and serum Cu concentrations in bladder carcinoma cases. Bladder carcinoma may be associated with Ca metabolic disorder, leading to higher urinary Ca and lower serum Ca. Low serum Se and smoking appear to be other risk factors for bladder carcinoma in China.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.83-94
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• 2003

Concentrated releases of zinc into water usually results from discharges associated with industrial purpose. The released zinc into soil is corroded and released into water. In aquatic environment, exess zinc is toxic to the organisms and causes the growth inhibition and malformation of them as a heavy metal. In this study, excess zinc toxicity was tested by FETAX (frog embryo teratogenetic assay with Xenopus)as in vivo system. Xenopus embryos at st.9 were exposed to $100{\sim}900\;{\mu}M$ of zinc for 7 days and 81% of individuals were survived in 100 ${\mu}M$, and 25% were survived in 1000M of zinc solution. In external malformations, swelled belly and intestinal dysplasia were common, and all of tested individuals showed these malformations in 200 ${\mu}M$ or higher concentration of zinc. In 400 ${\mu}M$ or higher concentration, all of tested tadpoles showed faded heart. Also, hypo-pigmentation, lens hernia and loose digestive track were very frequently found in 100 ${\mu}M$ of zinc. The histological study with paraffin section of zinc treated tadpoles showed following abnormalities; regeneration of photoreceptor on retina, reduced vitreous chamber in eye, reduction of red blood cells in heart, abnormal liver, swelling of pronephric cell, muscle dysplasia and palatal papilloma. These abnormalities may be caused by the degeneration of mitochondria, inhibition of cell adhesion, and the formation of leghemoglobin by zinc due to the substitution of $Ca^{2+}$ by $Zn^{2+}$. The body length was reduced due to the excess zinc. From a statistical result, body lengths of 300 ${\mu}M$ or higher concentrative g개ups was significantly reduced comparing that of control group. Recently, many spontaneous malformations and reduction of amphibians are reported, From the results of present study, excess zinc mi호t be a factor of amphibian reduction, and the control of zinc discharges is very important.

• Natural Product Sciences
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• v.21 no.3
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• pp.155-161
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• 2015

Peroxynitrite (ONOO⁻)-scavenging activities of nine Compositae herbs consisting of three Ixeris, two Youngia, two Cirsium and one of each Lactuca and Taraxacum species were evaluated. The contents of their ONOO⁻ scavengers in the extracts were also determined on a HPLC using seven standard compounds, chlorogenic acid (CGA), chicoric acid (CA), luteolin 7-glucoside (luteolin-7-glc), luteolin 7-glucuronide (luteolin-7-glcU), luteolin, linarin and pectolinarin. Five of those compounds exhibited potent ONOO⁻-scavenging activities: IC₅₀, CA (0.76 μM), CGA (1.34 μM), luteolin (0.81 μM), luteolin-7-glc (0.86 μM) and luteolin-7-glcU (3.13 μM). Both CA and luteolin-7-glc were highly contained in I. dentata (19.71 mg/g and 13.58 mg/g, respectively), I. dentata var. albiflora (17.58 mg/g and 23.83 mg/g, respectively) and I. sonchifolia (65.71 mg/g and 6.99 mg/g, respectively). Among the nine herbs, those three Ixeris species had very low IC₅₀ values over the range of 0.48 - 1.74 μg/mL, suggesting that they could be potential therapeutic vegetables, particularly for preventing diabetic complications or obesity, which can be caused by an excess production of ONOO⁻.

• Asian Journal of Turfgrass Science
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• v.11 no.2
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• pp.89-95
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• 1997

Soil chemical properties were investigated to elucidate vertical movement of mineral nutrients in a fairway slope of 27 year-old golf course. Soil samples were taken at every 10cm depth to 4Ocm on 4 sites 20m apart each along two parallel lines 60m apart on the slope(15˚) in August. Accord-ing to the similarity of vertical distribution pattern they could be classified into 6 distinctive groups(magnesium, nitrate, phosphorus, ammonium, manganese and copper) and the slope tended to affect the vertical movement of minerals. The contents of Ca and Mg increased with depth while NO$_3$-N and Zn decreased and correlated positively. Soil pH showed significant positive correlation with depth, Ca and Mg. Phosphorus content was highest in 10~20cm depth and decreased resulting in relatively high content in 30~40cm depth of the bottom site of slope. Iron distribution pattern was similar to phosphorus. Potassium and $NH_4$showed various(irregular) patterns. Mn was highest in the deep layer at the lower sites of slope but it was reverse at the upper sites and negatively correlated with Fe. Cu content incresed with depth and heighest in 20~30cm depth. Electroconductivity showed significant positive correlation with $NO_3$-N. Magnesium, cal-cium and copper seem to be prone to defficiency due to fast leaching, and nitrate and phosphorus prone to excess problem. Preventive measures on acidification of surface soil should be taken.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.213-218
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• 2019

BACKGROUND: Monitoring of the dynamic changes of chemical properties in agricultural land is very important for agricultural sustainability. Chemical properties of agricultural soils in Korea have been investigated at four-year interval in the order of paddy, plastic film house, upland, and orchard soils since 1999. METHODS AND RESULTS: Total 8,160 topsoil samples were taken from the upland in 2001, 2005, 2009, 2013, and 2017, respectively. Soil chemical properties such as pH, electrical conductivity (EC), organic matter (OM), available phosphate (Avail. $P_2O_5$), and exchangeable (Exch.) cations (K, Ca, and Mg) were analyzed. Soil pH and Exch. Ca contents have increased since 2001. Average concentration of Avail. $P_2O_5$ increased from $547mg\;kg^{-1}$ in 2001 to $657mg\;kg^{-1}$ in 2017. Average concentration of Exch. Ca in 2017 was higher than the upper limit of its optimal range for upland cultivation. Excess and deficiency of chemical properties of upland soils comply with soil analysis and fertilizer prescription. CONCLUSION: We concluded that excessive nutrient in upland needed to be properly managed with soil test.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2106-2112
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• 2018

Concanavalin A (ConA) interacts with carbohydrates as a lectin, and recent reports proposed its application for detecting a diversity of viruses and pathogens. Structural studies have detailed the interaction between ConA and carbohydrates and the metal coordination environment with manganese and calcium ions (Mn-Ca-ConA). In this study, ConA was crystallized with a cadmium-containing precipitant, and the refined structure indicates that $Mn^{2+}$ was replaced by $Cd^{2+}$ (Cd-Ca-ConA). The structural comparison with ConA demonstrates that the metal-coordinated residues of Cd-Ca-ConA, that is Glu8, Asp10, Asn14, Asp19, and His24, do not have conformational shifts, but residues for sugar binding, including Arg228, Tyr100, and Leu99, reorient their side chains, slightly. Previous studies demonstrated that excess cadmium ions can coordinate with other residues, including Glu87 and Glu183, which were not coordinated with $Cd^{2+}$ in this study. The trimeric ConA in this study coordinated $Cd^{2+}$ with other residues, including Asp80 and Asp82, for complex generation. The monomer does not have specific interaction near interface regions with the other monomer, but secondary cadmium coordinated with two aspartates (Asp80 and Asp82) from monomer 1 and one aspartate (Asp16) from monomer 2. This study demonstrated that complex generation was induced via coordination with secondary $Cd^{2+}$ and showed the application potential regarding the design of complex formation for specific interactions with target saccharides.

• Journal of Nutrition and Health
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• v.20 no.6
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• pp.395-404
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• 1987

A nutritional quality and rancidity of marketed korean traditional foods were assessed. That is, basic chemical analysis were done in Galbi-tang, Sullung-tang, Pibimbap, Pulkogi and Naeng Myon. Ca and P for the Galbi-tang and Sulung-tang and vitamin C for the Pibimbap were analyzed. Chemical analysis were done in Gangjung 4, Sanja 1, Parksan 6, Yoomilkwa, 4 out of korean traditional cookies. Amounts of energy and protein in Galbi -tang and protein and Ca in Sullung -tang are more than the recommended allowance at ta meal. Amounts of Ca in Galbi-tang and energy in SUllung-tang are less than the recommended . The amounts of energy and protein in Pibimbap, Pullkigi and Naeng Myon Except protein in Pullkogi are short of the recommended at a meal. And amounts of vitamin C in Pibimbap are short of the recommended, too. The content of carbohydrate in Korean traditional cookies is the highest one comparing to others. Contents of crude fat in Gangjung Parksan and Dasik which are made up of sesame, black sesame and pine nuts are higher than that of other Korean traditional cookies. Acid value and peroxide value in all Gangjung, Yoomilkwan and Sanja except the peroxide value in one Sanja product, are not in the excess of standard of peroxide value and acid value. The standard are 600meq/kg and 3 for peroxide value and acid value respectively in oil treated foods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.180-183
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• 1985

Percent dormant root and percent missing root were investigated in ginseng (Panax ginseng) plantations and correlated with soil chemical characteristics. Percent dormant root showed no consistency with root age and significant positive correlation with percent missing root in many cases. Percent dormant root showed significant positive correlation with available phosphorus and phosphorus-moisture ratio in soils. Percent missing root showed significant negative correlation with moisture and calcium in soil and positive one with phosphorus - moisture ratio. Above results strongly suggest that excess phosphorus and water stress are the common causes of dormancy and missing of root.