• Bulletin of the Korean Chemical Society
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• 제19권7호
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• pp.766-770
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• 1998

On-line preconcentration by direct precipitation with hydroxide has been developed and applied for the analysis of Cd in Inductively Coupled Plasma Atomic Emission Spectrometry. Cadmium is continuously precipitated with hydroxide and dissolved by nitric acid in on-line mode. Currently, the enrichment factor is more than 90 times for 20.0 mL of sample and could be further increased very easily. For a large sample throughput, 1.0 mL of sample loop is used and the enrichment factor is 4.5 with the sampling speed of 15/hr. The method has been applied to the analysis of NIST reference sample and has yielded good results with the certified value.

• 환경생물
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• 제29권4호
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• pp.265-273
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• 2011

Bacterial diversity based on the denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA gene sequences was determined for soil samples from two abandoned mine sites and the corresponding enrichment cultures using soil sample as key inoculum. Sequencing analysis of DGGE bands obtained from both the soil samples matched mostly with sequences of uncultured and newly described organisms, or organisms recently associated with the acid mine drainage environment. However, the enrichment of soil samples in ferrous sulfate and elemental sulfur media yielded sequences that were consistent with well-known iron- and sulfur-oxidizing acidophilic bacteria. Analysis of enrichment cultures of soil samples from Dalsung mine revealed abundant ${\gamma}$-$Proteobacteria$, whereas that of Gubong mine sample displayed acidophilic groups of ${\gamma}$-$Proteobacteria$, ${\alpha}$-$Proteobacteria$, $Actinobacteria$ and $Firmicutes$. Chemical elemental analysis of the mine samples indicated that the Dalsung site contained more iron and sulfate along with other toxic components as compared with those of the Gubong site. Biogeochemistry was believed to be the primary control on the acidophilic bacterial group in the enrichment samples.

• Journal of Radiation Protection and Research
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• 제36권1호
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• pp.16-23
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• 2011

보다 정확한 우라늄 농축도 분석은 핵물질 관리를 위하여 중요하다. 본 연구에서는 감마선을 이용한 우라늄 농축도 분석에서 시료와 검출기 사이에 차폐체가 있는 경우와 측정시간 변화에 따른 분석결과에 대한 정확성 평가 및 오차분석을 수행하였다. 우라늄 농축도를 분석하기 위하여 FRAM (Fixed energy Response function Analysis with Multiple efficiencies)을 이용하였다. FRAM에 의한 분석결과의 정확성은 화학 분석 결과와의 비교를 통해 평가되었다. 연구결과 선원과 검출기사이에 차폐체가 존재할 경우 차폐체의 두께변화에 따른 감마선의 세기는 지수함수 형태로 감소하며 감마선에너지 피이크의 반치폭 (FWHM : Full Width at Half Maximum)은 차폐체의 두께에 영향을 거의 받지 않는 것을 보였다. 따라서 시료와 검출기 사이에 차폐체가 있는 경우의 우라늄 농축도 분석에서 FRAM을 이용한 감마선분광 분석은 유용하게 활용될 수 있다. 본 연구 결과는 차폐체 안에 우라늄이 있는 경우 핵물질 분석에 기여할 수 있을 것이 기대된다.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3298-3302
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• 2012

Although offline enrichment of phosphorylated peptides is widely used, enrichment for phosphopeptides using $TiO_2$ is often performed manually, which is labor-intensive and can lead to irreproducible results. To address the problems associated with offline enrichment and to improve the effectiveness of phosphopeptide detection, we developed an automated online enrichment system for phosphopeptide analysis. A standard protein mixture comprising BSA, fetuin, crystalline, ${\alpha}$-casein and ${\beta}$-casein, and ovalbumin was assessed using our new system. Our multidimensional system has four main parts: a sample pump, a 20-mm $TiO_2$-based column, a weak anion-exchange, and a strong cation-exchange (2:1 WAX:SCX) separation column with LC/MS. Phosphorylated peptides were successfully detected using the $TiO_2$-based online system with little interference from nonphosphorylated peptides. Our results confirmed that our online enrichment system is a simple and efficient method for detecting phosphorylated peptides.

• The Journal of Asian Finance, Economics and Business
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• 제8권1호
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• pp.1031-1040
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• 2021

The purpose of this research is to analyze the influence of job enrichment and empowerment on organizational commitment. In addition, the role of work motivation and job satisfaction in mediating the influence of job enrichment and employee empowerment on organizational commitment has also been examined in this study. The sample population consists of all the employees in the regional office of DJKN Bali and Nusa Tenggara, who hold executive positions and have served the office for ≥ 4 years. This study adopts the second-order Partial Least Square (PLS) model and the Smart PLS Version 3.0 program which is used as the analysis tool. The results revealed that: job enrichment has a significant influence on organizational commitment; employee empowerment has an insignificant influence on organizational commitment; work motivation and job satisfaction partially mediate the influence of job enrichment on organizational commitment; work motivation and job satisfaction fully mediate the influence of employee empowerment on organizational commitment. The findings can be used as organizational considerations in developing policies related to job enrichment and employee empowerment, which is expected to motivate and provide satisfaction for employees and improve their organizational commitment.

• Mass Spectrometry Letters
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• 제6권2호
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• pp.31-37
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• 2015

Phosphorylation upon protein is well known to a key regulator that implicates in modulating many cellular processes like growth, migration, and differentiation. Up to date, grafting of multidimensional separation techniques onto advanced mass spectrometry (MS) has emerged as a promising tool for figuring out the biological functions of phosphorylation in a cell. However, advanced MS-based phosphoproteomics is still challenging, due to its intrinsic issues, i.e., low stoichiometry, less susceptibility in positive ion mode, and low abundance in biological sample. To overcome these bottlenecks, diverse techniques (e.g., SCX, HILIC, ERLIC, IMAC, TiO₂, etc.) are continuously developed for on-/off-line enrichment of phosphorylated protein (or peptide) from biological samples, thereby helping qualitative/quantitative determination of phosphorylated protein and its phosphorylated sites. In this review, we introduce to the overall views of enrichment tools that are universally used to selectively isolate targeted phosphorylated protein (or peptide) from ordinary ones before MS-based phospoproteomic analysis.

• 분석과학
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• 제29권1호
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• pp.29-34
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• 2016

염소로 소독된 음용수에서 수백 ng/L의 농도까지 검출되는 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone(MX)를 시료 농축 후 액-액 추출(LLE), 메틸 유도체화 및 GC-MS로 정량 분석하였다. 4 L의 물 시료를 감압회전증발기를 사용해 30 ℃에서 0.4 L로 농축하였다. 물 중의 MX는 ethyl acetate(100 mL × 2)를 용매로 사용하여 추출하였으며, 추출액 중 MX는 10 % H₂SO₄ in methanol로 methyl 유도체를 만들었다. MX의 회수율은 73.8 %이었으며, 이는 수지 흡착법의 38.1 %보다 높았다. 정량한계와 반복성(RSD)은 각각 10 ng/L와 2.2 %로 추정되었다. 이 결과는 시간이 더 많이 소요되는 수지 흡착법의 대체 방법으로 LLE가 사용될 수 있다는 것을 보여 주었다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.651-657
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• 2009

Shifts in the activity and diversity of microbes involved in aliphatic and aromatic hydrocarbon degradation in contaminated soil were investigated. Subsurface soil was collected from a gas station that had been abandoned since 1995 owing to ground subsidence. The total petroleum hydrocarbon content of the sample was approximately 2,100 mg/kg, and that of the soil below a gas pump was over 23,000 mg/kg. Enrichment cultures were grown in mineral medium that contained hexadecane (H) or naphthalene (N) at a concentration of 200 mg/l. In the Henrichment culture, a real-time PCR assay revealed that the 16S rRNA gene copy number increased from $1.2{\times}10^5$to $8.6{\times}10^6$with no lag phase, representing an approximately 70-fold increase. In the N-enrichment culture, the 16S rRNA copy number increased about 13-fold after 48 h, from $6.3{\times}10^4$to $8.3{\times}10^5$. Microbial communities in the enrichment cultures were studied by denaturing gradient gel electrophoresis and by analysis of 16S rRNA gene libraries. Before the addition of hydrocarbons, the gas station soil contained primarily Alpha- and Gammaproteobacteria. During growth in the H-enrichment culture, the contribution of Bacteriodetes to the microbial community increased significantly. On the other hand, during N-enrichment, the Betaproteobacteria population increased conspicuously. These results suggest that specific phylotypes of bacteria were associated with the degradation of each hydrocarbon.

• Animal Bioscience
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• 제34권9호
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• pp.1544-1551
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• 2021

Objective: The purpose of this study was to investigate growth performance, carcass traits, meat quality and hair follicle development of growing Rex rabbits as affected by different environmental enrichment materials. Methods: A total of one hundred and twenty Rex rabbits were randomly assigned to four groups; reared in conventional cages (not enriched) and in enriched cages with either willow stick (WS), rubber duck, or a can containing beans (CB), for 44 days. Results: The average daily gain of the CB group was the highest and had a significant difference from that of the other groups (p<0.05). The spleen and cecum weight of the CB group was greater than those of the WS and control groups (p<0.05). The redness (Commission Internationale de l'Eclairage a^*) of the meat sample of the control group was lower than those of the enriched cage groups (p<0.05). Moreover, the hue value of the CB group was significantly lower than that of the other groups (p<0.05). The tenderest meat belonged to the CB group. In addition, more secondary (p<0.05) and primary follicles were found in the CB group than in the control group. Conclusion: Environmental enrichment increased the average daily gain and improved some carcass traits, meat quality, and hair follicle density. Among the three environmental enrichment materials, CB could be recommended for rabbit husbandry.

• 한국식품위생안전성학회지
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• 제35권4호
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• pp.319-325
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• 2020

신선편이채소는 주로 가열하지 않은 채로 많이 섭취되는 식품으로, 신선편이채소 섭취로 인한 식중독 사고의 위험이 지속적으로 발생하고 있다. 특히, 바실러스 세레우스는 전 세계적으로 신선편이채소에서 검출되고 있는 주요 병원성 세균이다. 본 연구에서는 신선편이채소에서 바실러스 세레우스를 신속하게 검출하기 위해 증균배양과 PCR 분석법을 조합하여 반정량 신속검출법을 개발하였다. 신선편이 양상추와 어린잎채소를 대상으로, 바실러스 세레우스 균주(KCTC1013, KCTC1014, KCTC1092, KCTC1094, KCTC3624)의 최종농도가 1, 2, 3, 4, 5 log CFU/g이 되도록 접종시킨 후 0.15% polymyxin B를 포함한 TSB 배지를 이용하여 42℃에서 0, 2, 3, 4, 5, 6, 7 시간 동안 증균배양하였다. 증균배양액 1 mL을 취하여 mannitol-egg yolk-polymyxin agar에 배양한 후 균수를 정량하였고, 1 mL의 증균배양액에서 DNA를 추출한 후 PCR 분석을 진행하였다. 또한, 신선편이채소 시료(sample)에 대한 바실러스 세레우스 검출결과를 정확하게 판단하기 위해 신선편이채소 시료(sample)의 최소분석 sub-sample수를 확인하고자, 5개의 sub-sample을 이용하여 분석하였다. 증균배양과 PCR 분석법을 이용하여 확인한 연구결과, 신선편이 양상추에 접종되어 있는 5, 4, 3, 2, 1 log CFU/g의 바실러스 세레우스는 3, 4, 5, 6, 7 시간 증균배양 후에 검출되었고, 신선편이 어린잎채소에 접종되어 있는 5, 4, 3, 2, 1 log CFU/g의 바실러스 세레우스는 2, 3, 4, 5 시간동안 증균 배양한 후에 검출되었다. 또한, 신선편이채소 시료(sample)의 최소분석 sub-sample수는 3개로 확인되었다. 본 연구결과는 신선편이채소에 오염되어 있는 바실러스 세레우스의 반정량 신속검출법으로 활용될 수 있을 것이라 판단된다.