• Environmental Engineering Research
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• v.16 no.3
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• pp.137-148
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• 2011

In this study, a series of experiments was conducted on the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and $17{\alpha}$-ethinyl estradiol (EE2) in a single-component aqueous solution using 28 and 580 kHz ultrasonic reactors. The experiments were conducted with three different types of model water: deionized water (DI), synthetic brackish water (SBW), and synthetic seawater (SSW) at pH 4, 7.5, and 11 in the presence of inert glass beads and humic acids. Significantly higher sonochemical degradation (93-97% for BPA) occurred at 580 kHz than at 28 kHz (43-61% for BPA), regardless of water type. A slightly higher degradation was observed for EE2 compared to that of BPA. The degradation rate of BPA and EE2 in DI water, SBW, and SSW after 30 min of ultrasound irradiation at 580 kHz increased slightly with the increase in pH from 4 (0.073-0.091 $min^{-1}$ for BPA and 0.081-0.094 $min^{-1}$ for EE2) to 7.5 (0.087-0.114 $min^{-1}$ for BPA and 0.092-0.124 $min^{-1}$ for EE2). In contrast, significant degradation was observed at pH 11 (0.149-0.221 $min^{-1}$ for BPA and 0.147-0.228 $min^{-1}$ for EE2). For the given frequencies of 28 and 580 kHz, the degradation rate increased in the presence of glass beads (0.1 mm and 25 g) for both BPA and EE2: 0.018-0.107 $min^{-1}$ without beads and 0.052-0.142 $min^{-1}$ with beads for BPA; 0.021-0.111 $min^{-1}$ without beads and 0.054-0.136 $min^{-1}$ with beads for EE2. A slight increase in degradation of both BPA and EE2 was found as the concentration of dissolved organic carbon (DOC, humic acids) increased in both SBW and SSW: 0.107-0.115 $min^{-1}$ in SBW and 0.087-0.101 $min^{-1}$ in SSW for BPA; 0.111-0.111 $min^{-1}$ in SWB and 0.092-0.105 $min^{-1}$ in SSW for EE2. After 30 min of sonicating the humic acid solution, DOC removal varied depending on the water type: 27% (3 mg $L^{-1}$) and 7% (10 mg $L^{-1}$) in SBW and 7% (3 mg $L^{-1}$) and 4% (10 mg $L^{-1}$) in SSW.

• Environmental Engineering Research
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• v.23 no.1
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• pp.28-35
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• 2018

$17{\alpha}-ethinylestradiol$ (EE2), a synthetic estrogen which interfere the endocrine and reproductive function in living organisms, has been found extensively to be deposited into municipal wastewater treatment plants and the environment via human excretion. EE2 has long been known to be efficiently cometabolized by ammonia-oxidizing bacteria (AOB) during ammonia ($NH_3$) oxidation. Current study aims to investigate the effect of culture history on the biotransformation of EE2 by nitrifying sludge which was enriched under different ammonia loading rates in continuous flow reactors. Result showed that past growth condition largely affected not only the metabolic rate of $NH_3$ oxidation but also EE2 cometabolism. Sludge previously acclimated with higher $NH_3$ loads as well as sludge dominated with AOB belong to high growth cluster (Nitrosomonas europaea-Nitrosococcus mobilis) showed higher rate of EE2 biotransformation than those one being acclimated with lower $NH_3$ loads because of its ability to provide more reducing power from $NH_3$ oxidation. Moreover, the correlation between the degradation rates of $NH_3$ and EE2 was higher in sludge being acclimated with higher load of $NH_3$ in comparison with other sludge. Implication of the findings emphasized the role of volumetric $NH_3$ loading rate in determining EE2 removal in wastewater treatment system.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.141-144
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• 2005

J2EE 환경 기반의 IBM DB2 for z/OS 데이터 베이스를 적용한 어플리케이션에서 성능이 상대적으로 저하되는 문제가 발생 하였다. 즉, J2EE (Java 2, Enterprise Edition) 환경에서 동일한 어플리케이션을 Unix 서버의 오라클 데이터 베이스와 IBM DB2에 적용하여 비교한 결과 DB2부문에 대한 TPS가 작고 Transaction Elapsed Time이 오래 걸리며 CPU Utilization이 낮았다. 이러한 초기 결과값을 Baseline으로 설정하여 DB2를 데이터 베이스 서버로 사용하는 경우 어플리케이션의 성능을 개선 하기 위한 요소를 도출하고 성능 향상을 위한 조정 작업을 통해 DB2의 성능을 개선했다.

• Hwankyungkyoyuk
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• v.16 no.2
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• pp.65-73
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• 2003

This study has an aim to construct a reference frame to analyze the appropriateness of environmental education(EE) materials of elementary schools, and to search the basic direction of the scheme for analysis. In addition, this study has an aim to induce what the results of this analysis suggests for the development and reconstruction of EE materials. It was analyzed how truly EE materials reflected contents selected as an analysis scheme, after grasping practical use and features of textbooks, audio-visual materials, and a web-site that are typical materials in EE of elementary schools. The results in textbook analysis were that there were a human-centered environmentalism in the EE unit ("Environmentally Sound National Development", 5th Grade) of Social Studies. The result in analysis of audio-visual materials "Environmental Warrior, Zentaforce" of EBS, were that there are unhealthy environmentalism in that material. In other words, technology itself is considered as a almighty means to solve environmental problems. Finally, the result in web-site analysis were that the "Environmental Class" of Ministry of Environment did not have sound environmentalism. The above result of study shows us that the most important thing in developing and using the environmental education materials is to have sound environmental values and EE perspective, to evaluate EE material with various point of view, to judge its result, and to use it.

• Journal of the Korean Society of Tobacco Science
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• v.32 no.2
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• pp.88-94
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• 2010

The ether extract(EE) of leaf tobacco contains diverse compounds such as lipid, resinoid, paraffin hydrocarbons and pigments. Although the correlation of EE concentertion with leaf tobacco has not been established clearly, it is known that in some concentration range, EE concentration of leaf tobacco exerts good influence on the quality of tobacco. Recently, The American Oil Chemist's Society introduced new method(Am 5-04; AOCS, 2009) to determine EE concentration by AT15 extractor. This method is based on extraction with organic solvent at relatively high temperature and pressure, which significantly reduces the extraction time and ensures safety. The aim of this study is to optimize analytical condition of AOCS method for analyzing EE concentration of leaf tobacco. When sample pre-drying time and extraction time of XT15 were set to 3 hour and 30 minute and 30 minute respectively, EE concentration obtained from AOAC method. Statistical analysis(T-test) showed that there is no difference(P>0.05) between EE concentrations from two methods.

• Hwankyungkyoyuk
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• v.16 no.2
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• pp.39-50
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• 2003

Secondary school environmental education is offered mostly in extra-curricular activities, not included in the school curriculum. Therefore, drawing out its curriculum has been left to teachers' discretion. Teachers' beliefs in EE have much more influence on the selection of content of EE than any other psychological factors. It follows that the reality of school EE depends on what teachers believes about EE and which content of EE they select according to their beliefs. This study is to research the realities of the secondary school EE: examine teachers' beliefs about EE and analyse environmental views in their environment-related programs; examine whether teachers' programs reflect their beliefs and environmental views; identify the factors which teachers inhibit teachers from their expression of these beliefs. To identify what perspective was reflected to these programs, this study employs environmentalism. Environmentalism can be classified into 3 categories: environmental management; deep ecology; social ecology. Data were gathered by means of in-depth interviews with five teachers. To show teachers' beliefs clearly, the analysis of the data was conducted on the basis of 5 categories: 'ecological sensitivity', 'value education', 'behaviors', 'issues', 'perception of a cause of environmental problems, related to social structures'. These belifs reflect deep ecological perspective and social ecology. But these perspectives did not accord with those in programs. Most EE programs included only the deep ecological perspective. They didn't reflect their beliefs that students should perceive the cause of environmental problems in the social structure. The factors which teachers find as inhibiting or supporting their expression of these beliefs were analysed as following: (1) EE requests the change of curriculum and methods of instruction; (2) teachers should acquire 'environmental consciousness' and environmentrelated knowledge; (3) programs requests an administrative and financial support.

• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.7-12
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• 1994

A calf and 50 mice were infected with Cryptosporidium parvum and their fecal materials were collected and treated 10 ether extraction (EE), followed by discontinuous sucrose gradients (DSG) method. EE method was to remove some of fat or lipid from feces. Sediments were washed by centrifugation ($1,500{\;}{\times}{\;}g$ for 10 min., 3 times) In phosphate-buffered saline and then these washed sediments were sleeved sequentially through stainless steel screens with a final mesh of 250 ($61{\;}{\mu\textrm{m}}$ porosity) to remove other debris. After sieving, the materials were suspended in 2.5% potassium dlchromate solution. Oocysts were counted by using a hemocytometer and the recovery rate of pure oocysts was calculated on the basis of the count. Following centrifugation ($1,500{\;}{\times}{\;}g$ for 30 min.) by DSG method, most oocysts were recovered at the interface between a gravity of 1.103 and 1.064. The recovery rates of pure oocysts from the fecal suspension of the calf ($3.8{\;}{\times}{\;}10^7/ml$) and the mouse ($3.2{\;}{\times}{\;}10^6/ml$) treated with EE method were 81.6% and 51.6%, respectively. It is suggested that the recovery rate was dependent on the number of oocysts In each suspension treated with EE method. To get the 50% recovery rate, there must be more than $2{\;}{\times}{\;}10^6$ oocysts per ml of the fecal suspension treated with EE method. By the combination of the two methods it was possible to isolate C. parvum oocysts from normal feces of the calf and mouse as well as from dlarrhelc feces.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.4
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• pp.260-264
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• 2010

In this paper, Ni silicide is formed on boron cluster ($B_{18}H_{22}$) implanted source/drains for shallow junctions of nano-scale CMOSFETs and its thermal stability is improved, using vacuum annealing. Although Ni silicide on $B_{18}H_{22}$ implanted Si substrate exhibited greater sheet resistance than on the $BF_2$ implanted one, its thermal stability was greatly improved using vacuum annealing. Moreover, the boron depth profile, using vacuum post-silicidation annealing, showed a shallower junction than that using $N_2$ annealing.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1080-1084
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• 1994

Asymmetric inducing effects of substituents attached at nitrogen, the 5-position and boron in oxazaborolidine rings on asymmetric borane reduction of ketones were investigated. Thus, the effect of N-substituents examined with the oxazaborolidines prepared from (lR,2S)-N-alkyl norephedrine derivatives showed the remarkable decrease of enantioselectivities of the product alcohols by the variation of the steric size of alkyl groups on nitrogen from Me${\leftrightarro}$n-Bu(${\simeq}$Bn)${\leftrightarro}$ neopentyl${\leftrightarro}$i-Pr, such as 83${\%}$ ee with 5b, 22${\%}$ ee with 5c, 23${\%}$ ee with 5f, 16${\%}$ ee with 5e, and 3${\%}$ ee with 5d for the reduction of acetophenone. The presence of diphenyl groups at the 5-position enhanced the enantioselectivities dramatically. The effect of B-alkyl substituents in the oxazaborolidines derived from (lR,2S)-ephedrine showed that the enantioselectivities of product alcohols decreased gradually when the substituents were changed from hydrogen to steric bulky groups such as methyl, n-butyl, thexyl and phenyl.

• Journal of Life Science
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• v.26 no.2
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• pp.147-154
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• 2016

Osteosarcoma (OS) is the most common and malignant bone tumors. Although many types of resection surgery and experimental agents were developed, median survival and clinical prognosis are poorly investigated. Recently, several researches have reported that Eucheuma cottonii has potent as protective effects of coal dust-induced lung damage via inhibition of malondialdehyde (MDA) and oxidative stress in bronchoalveolar lavage fluids (BALF). However, anti-cancer effects and specific molecular mechanism of extract from Eucheuma cottonii (EE) has not been clearly studied yet. This study evaluated that anti-cancer potential of EE in human osteosarcoma Saos-2 cells. EE indicated cytotoxicity on Saos-2 cells in a dose-dependent manner. Morphological degradation and nucleic condensation were also observed under the EE treatment. However, it did not significantly affect on non-cancerous kidney HEK-293 cells under the same concentration which is shown cytotoxicity on Saos-2 cells. The phosphorylation of Fas-Associated Death Domain (FADD) and expression of cleaved caspase-8, -7 and -3 were upregulated in a dose-dependent manner. In immunofluorescence staining, expression level of Fas and cleaved PARP were upregulated by EE treatment. Furthermore, treatment of EE induces upregulation of sub G1 phase by flow cytometry analysis. The results demonstrated that EE has a therapeutic potential against osteosarcoma via FADD mediated caspase cascade apoptosis signal pathway.