• Journal of the Korean earth science society
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• v.27 no.3
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• pp.313-327
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• 2006

This study investigated the geochernical characteristics of Mn scale formed in groundwater wells at the Damyang area. The composition of Mn scale consists mainly of MnO and $SiO_2$. The content of Mn ranges from56.61wt.% to 68.69wt.%, and $SiO_2$ content ranges from 1.56wt.% to 10.45wt.%. The contents of Mo and Ba in Mn scale increased with increased depth; whereas, the content of Zn and Pb decreased with increased depth. Birnessite, quartz and feldspars were identified in Mn scales using x-ray powder diffraction studies. The IR absorption bands for Mn scales show major absorption band due to OH stretching, adsorbed molecular water, and birnessite stretching, respectively. In the SEM and EDS analysis, the Mn scale consists of botryoidal, spherical, spherulite, and empty straw structure. Those structure may be precipitated simply due to oversaturation with concentrated Mn content or may be formed through biogenic precipitation by Lepthothrix discophora. Under microanalysis using EDS on those structure surface of Mn scales, the Mn atomic percent range from 28 to 44, and such elements revealed the presence of Si, K, Na, Ca, Cl, Cu, Zn, and Ba.

• Journal of Microbiology and Biotechnology
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• v.30 no.1
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• pp.118-126
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• 2020

Silicon and phosphorus are elements that are beneficial for plant growth. Despite the abundant availability of silicate and phosphate in the Earth's crust, crop nutritional requirements for silicon and phosphorus are normally met through the application of fertilizer. However, fertilizers are one of the major causes of heavy metal pollution. In our study, we aimed to assess silicate and phosphate solubilization by the bacteria Enterobacter ludwigii GAK2, in the presence and absence of phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), to counteract cadmium stress in rice (Oryza sativa L). Our results showed that the GAK2-treated rice plants, grown in soil amended with phosphate [Ca₃(PO₄)₂] or silicate (Mg₂O₈Si₃), had significantly reduced cadmium content, and enhanced plant growth promoting characteristics including fresh shoot and root weight, plant height, and chlorophyll content. These plants showed significant downregulation of the cadmium transporter gene, OsHMA2, and upregulation of the silicon carrier gene, OsLsi1. Moreover, jasmonic acid levels were significantly reduced in the GAK2-inoculated plants, and this was further supported by the downregulation of the jasmonic acid related gene, OsJAZ1. These results indicate that Enterobacter ludwigii GAK2 can be used as a silicon and phosphorus bio-fertilizer, which solubilizes insoluble silicate and phosphate, and mitigates heavy metal toxicity in crops.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.365-370
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• 2012

Proximate composition, reducing sugar, and mineral content of several cultivars of Rehmannia glutinosa were analyzed. the moisture and soluble solid content of fresh Rehmannia glutinosa ('Korea', 'Kokang', 'Sewon 10', 'Sewon 11' and 'Jihwang 1') were 74.6~78.4% and $19.6{\sim}22.4^{\circ}Brix$, respectively. Proximate composition of dried Rehmannia glutinosa ranged from 82.91~86.94% carbohydrate, 3.38~5.70% crude protein, 2.5~3.0% crude ash and 3.47~3.80% fiber. Sugar composition by HPLC/ELSD showed that sucrose (4.49~7.75 g/100 g), raffinose (2.96~4.78 g/100 g) and stachyose (42.36~45.87 g/100 g) were present, whereas monosaccharides were not detected in 5 cultivars of dried Rehmannia glutinosa. Mineral compositions of dried Rehmannia glutinosa by ICP-AES were Ca (639.9~782.0 ppm), Fe (128.5~634.9 ppm), Na (119~150 ppm), K (6,639.1~10,448.0 ppm), Mg (372.2~981.8 ppm) and Zn (8.8~474.2 ppm). However, Co and Mo were not detected. Among 5 cultivars of Rehmannia glutinosa, 'Kokang' and 'Sewon 10' contain higher amounts of Fe, Ca, K, Mg, Cu and Zn than the other cultivars.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.867-879
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• 2015

To confirm basic nutrient contents of Korean honey as a food material, we assessed New Zealand Manuka honey by measuring proximate components, vitamin C and minerals of 16 kinds of honey harvested in South Korea. The proximate composition of each honey sample was as follows: moisture content 18.45~29.84%, crude protein 0.10~0.95% (vs Manuka honey 0.23%), crude fat 0.02~0.60% (vs Manuka honey 0.34%), crude ash 0.01~.52% (vs Manuka honey 0.24%) and carbohydrate 67.90~80.94% (vs Manuka honey 79.39%), respectively. In the case of free sugars analyze by HPLC, fructose showed a content of 26.12~49.84% which was highest in acacia honey and lowest in sorbus honey. Content of glucose was 19.38~36.12% and lowest in chestnut honey, whereas sucrose, lactose, maltose were absent. Total sugar contents were 64.16% which was less than Manuka honey (70.23%) and vitamin C was not detected in all samples. Minerals were detected 15~25 kinds, including K, Ca, Mg, Zn, Fe, Cu, Mo and so on. Ca was high in order of linden > canola > codonopsis > hedysarum honey, and K was higher than in Manuka honey in order of chestnut > hedysarum > codonopsis > jujube honey. Especially, these results suggest that Korean honey have a better nutrient content profile than Manuka honey.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.73-80
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• 2010

Functional and nutritional components of 7 cultivars of Chinese cabbage (CC; Brassica rapa subspecies campestris) from China were analyzed to compare the effects of soil pH (6.9 vs. 7.6). The CC grew on the soil of pH6.9 (CC-6.9) contained significantly increased amounts (2.3~4-fold) of pectin, crude protein, vitamin C and vitamin E compared to the control. The contents of ash and minerals (Ca, Fe, Na, Zn, K and Mn) were also significantly increased in CC-6.9. However, CC-6.9 contained 16-75% lower contents of reducing sugars, cellulose and crude fat than CC-7.6. CC-7.6 contained more glucosinolates than CC-6.9; gluconasturtiin (20.68 vs. 0.84 $nmol{\cdot}g^{-1}$ wet wt) and gluconapin (202.55 vs. 0.15 $nmol{\cdot}g^{-1}$ wet wt). In conclusion, CC-6.9 had an improved texture (high pectin and low cellulose) and nutritional value (high in protein, Ca, Fe, Zn, vitamin C, and E), whereas CC-7.6 had better taste (high in reducing sugars) and anticancer functionality (high in glucosinolates).

• Journal of the Mineralogical Society of Korea
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• v.23 no.3
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• pp.235-242
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• 2010

Froth flotation using the residual water in the end of flotation process has been performed through controlling of pH. IEP (isoelectric point) of molybdenite and quartz in distilled water was below pH 3 and pH 2.7, respectively and the stabilized range was pH 5~10. In case of a suspension in reusing water, zeta potential of molybdenite decreased to below -10 mV or less at over pH 4 due to residual flocculants. As result of pH control, flotation efficiency in the alkaline conditions was deteriorated by flocculation, resulting from expanded polymer chain, ion bridge of the divalent metal cations ($Ca^{2+}$), and hydrophobic interactions between the nonpolar site of polymer/the hydrophobic areas of the particle surfaces. However, the weak acid conditions (pH 5.5~6) improved the efficiency of flotation as hydrogen ions neutralize polymer chains and then weakened its function. In cleans after rougher flotation, the Mo grade of 52.7% and recovery of 90.1% could be successfully obtained under the conditions of 20 g/t kerosene, 50 g/t AF65, 300 g/t $Na_2SiO_3$, pH 5.5 and 2 cleaning times. Hence, we developed a technique which can continuously supply waste water filtered from tailings into the grinding-rougher-cleaning processes.

• The Journal of Korean society of community based occupational therapy
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• v.9 no.1
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• pp.25-34
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• 2019

Objective : The purpose of this study was to investigate the effect of cognitive level of mild cognitive impaired elderly living in the community on participation in activities and social networks as well as leisure and daily life activities. Methods : The elderly people aged 65 years or older living in the community were selected for the mild cognitive impairment with a score of MMSE-K of 15 or more and 23 or less. MoCA-K was applied in order to examine the cognitive abilities of the subjects and K-ACS and LSNS-18 were applied to confirm the activity participation level and social network index. Results : As a result of examining the relationship between cognition and activity participation, various sub-abilities(spatio-temporal abilities, vocabulary abilities, attention, abstract thinking) of cognition had a significant influence on instrumental activities of daily living, leisure activities and social activities. In addition, all of the sub - abilities of cognition showed a significant correlation with sub-elements of social network. Conclusion : Through this study, it was found that the general elements of cognition influenced activity participation and social network of various areas of mild cognitive impaired elderly people. We suggest that measures for enhancing participation and social participation of the elderly with mild cognitive impairment are provided through follow up studies.

• The Journal of Engineering Geology
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• v.24 no.4
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• pp.583-595
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• 2014

The chemical properties and composition (pH, CaO, Fe, $HCO{_3}^-$, and $SO{_4}^{2-}$) of groundwater (GW) and surface water (SW) from the northern (non-carbonate bedrock) and southern (carbonate bedrock) sections of the Daedong River, Pyeongyang were analyzed and compared period of the 1930s. In the southern section, the GW and SW has a higher pH and $SO{_4}^{2-}$ concentration, but lower $HCO{_3}^-$ and Fe levels than in the north. This finding reflects a reaction that formed acid by replacing metal ions in inorganic salts by hydrogen, which resulted from the oxidation of organic material in a clay layer.

• BMB Reports
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• v.31 no.3
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• pp.264-268
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• 1998

Dopamine (DA) acts on swimming motor neurons (SMNs) of Polyorchis penicillatus as an inhibitory neurotransmitter by hyperpolarizing their membrane potentials, which results from the activation of voltagesensitive potassium channels mediated through a $D_2-type$ receptor. In addition, DA, and not the hyperpolarized membrane potential, directly decreased the input resistance of SMNs by ca. 50% from 1.42 to 0.68 $G{\Omega}$. It strongly indicates that DA can shunt other excitatory synaptic signals onto SMNs where DA usually elicited much greater responses in their neurites than soma. All these evidences suggest that DA may operate in this primitive nervous system in dual modes as an inhibitory neurotransmitter and neuromodulator as well.

• BMB Reports
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• v.28 no.4
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• pp.323-330
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• 1995

Recent studies have shown that dopamine applied to cultured swimming motor neurons of Polyorchis penicillatus produces an inhibitory action by opening potassium channels through $D_2$-like receptors. In this study, it was demonstrated that dopamine found in the hydromedusa was not from exogenous sources and the content of dopamine depended on the $Ca^{2+}$ content of the dissecting media. In addition, a combination of thin layer chromatography and high performance liquid chromatography showed the presence of DOPA and DO PAC-like compounds in the jellyfish. The glyoxylic acid method for catecholamines suggested that a population of small cells, neither swimming motor neurons nor B-like neurons, had dopaminergic systems. From all these results, it is suggested here that DA synthesized from DOPA in some cells is released. being dependent on calcium concentrations, into a synaptic cleft and degraded into DOPAC after acting as an inhibitory transmitter to swimming motor neurons.