• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1102-1110
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• 2010

Tidal mudflat is a reservoir for diverse microbial resources. Microbial diversity in tidal mudflat sediment can be easily influenced by various human activities. It is necessary to take representative samples to monitor microbial diversity in tidal mudflat sediments. In this study, we analyzed the microbial diversity and chemical characteristics of vegetation and non-vegetation tidal mudflat regions in the Kangwha tidal mudflat using geo-statistics and data-mining. According to the geo-statistical analysis, most correlation range values for the vegetation region were smaller than those for the non-vegetation region, which suggested that the shorter number and interval of sampling are required for the vegetation tidal mudflat environment due to its higher degree of chemical and biological complexity and heterogeneity. The data-mining analysis suggested that the organic content and nitrate were the major environmental factors influencing microbial diversity in the vegetation region while pH and sulfate were the major influencing factors in the non-vegetation region. Using the geo-statistical and data-mining integration approach, we proposed a guideline for determining the sampling interval and number to monitor microbial diversity in tidal mudflat.

• Journal of Conservation Science
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• v.23
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• pp.81-93
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• 2008

The analysis of ancient DNA (aDNA) in paleogenetics has become an increasingly important subject of archaeological, anthropological, biological as well as public interest. In this study, paleogenetic analyses were carried out on the human skeletal remains from a historical cemetery site in Myeongam-ri, Asan, Korea. Archaeological records show that this particular location had been used as a habitation or mortuary site as early as the Bronze Age and up until the Joseon Dynasty. Human remains of twenty individuals out of forty-nine tombs from the Goryeo to Joseon Dynasty were selected for the analysis of this study. In order to identify the genealogy of the population and traditional burial pattern of the cemetery, we conducted comparative analyses of the hyper variable regions (HVRs) in mitochondrial DNA (mtDNA) of each sample. A number of cautious steps were taken at all experimental stages in order to avoid erroneous recombination by the segmental and modern contaminations derived from the researchers. We sequenced segmental amplicons of HVRs andassigned relevant haplogroups according to the sequence polymorphism on the basis of the known mtDNA database. The result shows that diverse haplogroups were unexpectedly present in the small population group of the Myeongam-ri site. This diversity appears to be related to the geographical conditions and archaeological properties of the Myeongam-ri site.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.2
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• pp.253-258
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• 2016

The $MnO_x-WO_3-TiO_2$ nanoscale powders were synthesized by sol-gel method in order to prevent the biological fouling on the ships and offshore structures. Powder characteristics and antifouling performance were investigated with respect to the crystalline, microstructure and surface property for application in self-polishing copolymer resins. The high antifouling activity of $TiO_2$-system biocide was attributed to its redox potential and soluble metal ions originating from tungsten oxides according to the improvements in the powder characteristics. Based on their physio-chemical characterizations, the specific surface areas of powders were about $90m^2/g$ and the grain size was in the region 100 ~ 150 nm. Powder characteristics and surface properties were improved by the addition of $WO_3$. Antifouling performance were analyzed according to their surface properties and static immersion tests to determine the effects of the $TiO_2$-system compounds. The surface of 2 wt. % added sample was clean for 5 month. This may be attributed to the ability of $MnO_x-WO_3-TiO_2$ powders to act as a promoter in antifouling agents.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.49-54
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• 2014

Background: Hydrogels are a class of polymers that can absorb water or biological fluids and swell to several times their dry volume, dependent on changes in the external environment. In recent years, hydrogels and hydrogel nanocomposites have found a variety of biomedical applications, including drug delivery and cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled actuation. Materials and Methods: In this work, synthesis of hydrogel nanocomposites containing magnetic nanoparticles are studied. At first, magnetic nanoparticles ($Fe_3O_4$) with an average size 10 nm were prepared. At second approach, thermo and pH-sensitive poly (N-isopropylacrylamide -co-methacrylic acid-co-vinyl pyrrolidone) (NIPAAm-MAA-VP) were prepared. Swelling behavior of co-polymer was studied in buffer solutions with different pH values (pH=5.8, pH=7.4) at $37^{\circ}C$. Magnetic iron oxide nanoparticles ($Fe_3O_4$) and doxorubicin were incorporated into copolymer and drug loading was studied. The release of drug, carried out at different pH and temperatures. Finally, chemical composition, magnetic properties and morphology of doxorubicin-loaded magnetic hydrogel nanocomposites were analyzed by FT- IR, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM). Results: The results indicated that drug loading efficiency was increased by increasing the drug ratio to polymer. Doxorubicin was released more at $40^{\circ}C$ and in acidic pH compared to that $37^{\circ}C$ and basic pH. Conclusions: This study suggested that the poly (NIPAAm-MAA-VP) magnetic hydrogel nanocomposite could be an effective carrier for targeting drug delivery systems of anti-cancer drugs due to its temperature sensitive properties.

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.241-249
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• 2020

This study investigated the whitening activity using seomaeyakssuk (Artemisia argyi H.) extract. Seomaeyakssuk was extracted from hot DW (AAD) and 70% ethanol (AAE). And confirmed safety through assessment of cytotoxicity. Also, whitening activities were measured through changes in the levels of extracellular melanin, melanin synthesis, cellular tyrosinase activity and transcription factor. The results confirmed that significant cytotoxicity does not appear in the concentration range of 50, 100, and 200 ㎍/㎖ of both extracts of this study. The production of extracellular melanin was slowed by AAD 45.0% and AAE 1.3% at 200 ㎍/㎖ concentration. Also, production of intracellular melanin was decreased AAD 37.2% and AAE 24.6%. In the case of intra cellular tyrosinase activity was reduced to AAD 49.2% and AAE 35.6% at 200 ㎍/㎖ concentration. The mRNA expression of tyrosinase, TRP-1 and TRP-2 significantly decreased by AAD 63.0%/AAE 58.0%, AAD 60.0%/AAE 56.0% and AAD 59.0%/AAE 53.0%, respectively, following the 200 ㎍/㎖ sample treatment when compared to the control. Both extracts showed efficient changes of production of whitening-related factor and transcription factor. But AAD was found to have a higher inhibitory effect than AAE. In other words, seomaeyakssuk was showed significant biological activities showing whitening without cytotoxicity. These results will be provided as fundamental data for further development of the new material of functional cosmetics to the results above.

• The Journal of Industrial Distribution & Business
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• v.10 no.8
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• pp.33-44
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• 2019

Purpose - As the scope of existing digital transformation expanded to various degrees, the Fourth Industrial Revolution came into being. In 2016, Klaus Schwab, Chairman of the World Economic Forum (WEF), said that the new technologies that lead the fourth industrial revolution are AI, Block chain, IoT, Big Data, Augmented Reality, and Virtual Reality. This technology is expected to be a full-fledged fusion of digital, biological and physical boundaries. Everything in the world is connected to the online network, and the trend of 'block chain' technology is getting attention because it is a core technology for realizing a super connective society. If the block chain is commercialized at the World Knowledge Forum (WKF), it will be a platform that can be applied to the entire industry. The block chain is rapidly evolving around the financial sector, and the impact of block chains on logistics, medical services, and public services has increased beyond the financial sector. Research design, data, and methodology - Figure analysis of data and social science analytical software of IBM SPSS AMOS 23.0 and IBM Statistics 23.0 were used for all the data researched. Data were collected from hotel employees in China from 25th March to 10th May. Results - The purpose of this study is to investigate the effect of the block chain characteristics of the existing hotel reservation system on the intention to use and to examine the influence of the block chain characteristics of the hotel reservation system on the intention to use, We rearranged the variables having the same or similar meaning and analyzed the effect of these factors on the intention to use the block chain characteristic of the hotel reservation system. 339 questionnaires were used for analysis. Conclusions - There are only sample hotel workers in this study, and their ages are in their 20s and 30s. In future studies, samples should be constructed in various layers and studied. In this study, the block chain characteristics are set as five variables as security, reliability, economical efficiency, availability, and diversity. Among them, Security and reliability made positive effects on the perceived usefulness. Also, security and economics did on the perceived ease. Availability and diversity did on both perceived usefulness and perceived ease. Perceived ease did on perceived usefulness. And perceived ease and perceived usefulness did on user intent. But security and economics did not on the perceived usefulness

• Journal of Radiation Protection and Research
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• v.23 no.4
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• pp.237-242
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• 1998

The goal of this work was to optimize the liquid scintillation counting techniques for the determination of C-14 in environmental samples such as biological and air samples. Carbon-14 activities in most environmental samples were measured with direct $CO_2$ absorption method. The highest figure of merit was found through the variation of Carbosorb $E^{TM}$ and Permatluor $V^{TM}$ ratio, in the measurement windows. The best condition was 1:1 volume ratio. Average 2.35 g of $CO_2$ was reproducibly absorbed in the 20 ml mixture within 40 min. The counting efficiency determined by repeated analysis of NIST oxalic acid standard and the background count rate were measured to be $58.8{\pm}1.4%$ and $1.88{\pm}0.06\;cpm$, respectively in case of saturated solution. The correction curves of counting efficiency for partially saturated solutions and for saturated solutions with quenching were prepared, respectively. The overall uncertainty of the sample specific activity for near background levels was estimated to be about 7 % for 4 hours counting at 95 % confidence level. The long-term stability of samples has been checked for all the counting techniques over a two week periods, and no apparent change in counting efficiency and background level was found at that time.

• Journal of Korean Academy of Nursing
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• v.22 no.4
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• pp.526-551
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• 1992

The purpose of this study was to identify the commonalities of various nursing interventions and effective intervention methods in each intervention through analysis and synthesis of many accumulated research papers. The study analyzed the effects of various nursing interventions on anxiety and /or stress. For this purpose, 64 experimental studies with randomized or nonequivalent control group pre-test-posttest design were selected from journals of medical and nursing schools, the Korean Nurse, the Korean Nurses' Academic Society Journal, the Cetnral Journal of Medicine, the New Medical Journal, the Nurse Monthly, and from theses and dissertations conducted from 1970 to 1991. The selected studies nor classified according to three characteristics : 1) the research samuel, 2) types and methods of nursing interventions, and 3) statistical tests. The following analysis was done : 1) Confirmation of the accuracy of data drawn from each study by paired review, 2) Estimation of the homogenity of pre-test scores of the dependent variable between control and experimental groups warranted the effect size of post-scores, 3) If the homogenity of pre-test scores did not warrant, the change scores from pre-test to post-test were used to estimate the effect size, 4) Use of the effect size of each study among homogenious studies was tested for each intervention method, such as relaxation, information, and touch and /or support. Finally, for the studies not showing homogenity, an ANOVA test was used to identify patterns for each intervention. Some findings are summarized as follow : The effect sizes for relaxation and information were greater than those for touch and /or supportive technique. Studies using random assignment had greater effect sizes than nonrandomized sample studies using the same intervention. For healthy people, group education was more effective than individual teaching. However, for patients, relaxation and touch and /or supportive techniques given on individual basis were more effective than when given in a group situation. Measuring anxiety and stress by biological indicators was less effective than by self-report. Budzynski's relaxation method was the most effective. The more frequently the techniques applied, the larger the effect size. On the bases of these findings, the following recommendations were made : 1. A combination of information, relaxtion, and touch-supportive techniques should be used for greater effect in reducing the level of anxiety and /or stress. 2. Information is the first choice of intervention to reduce the level of anxiety and /or stress of healthy People : other interventions may be added depending on the conditions of the subjects.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.185-185
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• 2007

Starting at the beginning q the 20th century, increasing amounts of tetrach1oroethene (PCE) and trichloroethene (TCE)were manufactured due to the extensive use of these compounds in industry, in the military, and in private households, mainly as nonflammable solvents. This widespread use, along with careless handling and storage, are among the most serious contaminants of soil, sediment and groundwater. Highly chlorinated ethenes are typically not degraded through oxygenation by aerobic bacteria Since complete reductive dechlorination of PCE and TCE to ethene (ETH) has been observed in anaerobic enrichment culture, anaerobic dehalorespiring bacteria have received increased attention in the last decade. Under anaerobic conditions, these compounds con be reductively dehalogenated to less-chlorinated ethenes or innocuous ethene by microorganism through dehalorespiration. We have been studying anaerobic enrichment culture which used lactate as the electron donor for reductive dechlorination of PCE to ETH the anaerobic mixed microbial culture was enriched from the sediment sample taken from site contaminated with PCE. PCE was consistently and completely converted to ethene. In addition, the accumulation of intermediate products such as 1,2-ds-dichloroethene (cis-DCE) and vinyl chloride (VC) was observed in the anaerobic mixed microbial culture. the established dechlorinating enrichment culture was analyzed by DGGE using primers specific to DefrJ1ococcoides 16S rRNA gene sequences. In conclusion, we established the PCE dechlorinating enrichment culture and confirmed the existence of Dehalococcoides in an enrichment culture.

• Korean Journal of Clinical Pharmacy
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• v.16 no.1
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• pp.23-27
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• 2006

Doxorubicin (DXR) is a type of anti-cancer drug called an 'anthracycline glycoside', It works by impairing DNA synthesis, a crucial feature of cell division, and thus is able to target rapidly dividing cells. Doxorubicin is a very serious anti-cancer medication with definite potential to do great harm as well as great good. A liquid chromatography-tandem mass spectroscopy (LC-MS/MS) method was developed to identify and quantify DXR in small-volume biological samples. After the addition of internal standard (IS, $5{\mu}L\;of\;1{\mu}M/ml$ daunorubicin methanol solution) into the serum sample, the drug and IS were extracted by methanol. Following vortex for a 1min and centrifugation at 15,000g for 10 min the organic phase was transferred and evaporated under a vacuum. The residue was reconstituted with $350{\mu}L$ of mobile phase and $10{\mu}L$ was injected into C18 column with mobile phase composed of 0.05M ammonium acetate (0.1 M acetic acid adjusted to pH 3.5) and acetonitrile (40:60, v/v). The flow rate was kept constant at $350{\mu}L/min$. The ions were quantified in the multiple reaction mode (MRM), using positive ions, on a triple quadrupole mass spectrometer. The lower limits of quantification for Doxorubicin in plasma and small tissues were approximately 0.5 ng/mL and 0.5 ng/mL respectively. Intra- and inter-assay accuracy (% of nominal concentration) and precision (% CV) for all analytes were within 15%, respectively.