• Title/Summary/Keyword: Bead process

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Remediation of Heavy Metal Contaminated Groundwater by Using the Biocarrier with Dead Bacillus sp. B1 and Polysulfone (Bacillus sp. B1 사균과 Polysulfone으로 이루어진 미생물 담체를 이용한 중금속 오염 지하수 정화)

  • Lee, Min-Hee;Lee, Ji-Young;Wang, Soo-Kyun
    • Economic and Environmental Geology
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    • v.43 no.6
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    • pp.555-564
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    • 2010
  • Remediation process by using the bio-carrier (beads) with dead Bacillus sp. B1 and polysulfone was investigated for heavy metal contaminated groundwater. Sorption batch experiments using the bio-carrier were performed to quantify the heavy metal removal efficiencies from the contaminated solution. The analyses using SEM/EDS and TEM for the structure and the characteristic of precipitates on/inside the beads were also conducted to understand the sorption mechanism by the bio-carrier. Various amounts of freeze-dried dead Bacillus sp. B1 were mixed with polysulfone + DMF(N,N-dimethylformamide) solution to produce the bio-carrier (beads; less than 2mm in diameter) and 5% of Bacillus sp. B1 in the bio-carrier was optimal for Pb removal in the solution. The removal efficiency ratings of the bio-carrier for Pb, Cu and Cd were greater than 80% after adding 2g of bio-carrier in 50ml of aqueous solution (<10mg/L of each heavy metal concentration). Reaction time of the bio-carrier was very fast and most of the sorption reaction for heavy metals were completed within few hours. Batch experiments were duplicated at various pH conditions of aqueous solutions and Cu and Pb removal efficiencies highly maintained at wide pH ranges (pH 2-12), suggesting that the bio-carrier can be useful to clean up the acidic waste water such as AMD. From SEM/EDS and TEM analyses, it was observed that the bio-carrier was spherical shape and was overlapped by many porous layers. During the sorption experiment, Pb was crystallized on the surface of porous layers and also was mainly concentrated at the boundary of Bacillus sp. B1 stroma and polysulfone substrate, showing that the main mechanism of the bio-carrier to remove heavy metals is the sorption on/inside of the bio-carriers and the bio-carriers are excellent biosorbents for the removal of heavy metal ions from groundwater.

Measuring Intracellular Mycobacterial Killing Using a Human Whole Blood Assay (인체 전혈 모델을 이용한 세포내 결핵균 살균력에 관한 연구)

  • Cheon, Seon-Hee;Song, Ho-Yeon;Lee, Eun-Hee;Oh, Hee-Jung;Kang, In-Sook;Cho, Ji-Yoon;Hong, Young-Sun
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.5
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    • pp.497-509
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    • 2002
  • Background : The mechanisms through which cellular activation results in intracellular mycobacterial killing is only partially understood. However, in vitro studies of human immunity to Mycobacterium tuberculosis have been largely modeled on the work reported by Crowle, which is complicated by several factors. The whole blood culture is simple and allows the simultaneous analysis of the relationship between bacterial killing and the effect of effector cells and humoral factors. In this study, we attempted to determine the extent to which M. tuberculosis is killed in a human whole blood culture and to explore the role of the host and microbial factor in this process. Methods : The PPD positive subject were compared to the umbilical cord blood and patients with tuberculosis, diabetes and lung cancer. The culture is performed using heparinized whole blood diluted with a culture medium and infected with a low number of M. avium or M. tuberculosis $H_{37}Ra$ for 4 days by rotating the culture in a $37^{\circ}C$, 5% $CO_2$ incubator. In some experiments, methlprednisolone- or pentoxifyline were used to inhibit the immune response. To assess the role of the T-cell subsets, CD4+, CD8+ T-cells or both were removed from the blood using magnetic beads. The ${\Delta}$ log killing ratio was defined using a CFU assay as the difference in the log number of viable organisms in the completed culture compared to the inoculum. Results : 1. A trend was noted toward the improved killing of mycobacteria in PPD+ subjects comparing to the umbilical cord blood but there was no specific difference in the patients with tuberculosis, diabetes and lung cancer. 2. Methylprednisolone and pentoxifyline adversely affected the killing in the PPD+ subjects umbilical cord blood and patients with tuberculosis. 3. The deletion of CD4+ or CD8+ T-lymphocytes adversely affected the killing of M. avium and M. tuberculosis $H_{37}Ra$ by PPD+ subjects. Deletion of both cell types had an additive effect, particularly in M. tuberculosis $H_{37}Ra$. 4. A significantly improved mycobacterial killing was noted after chemotherapy in patients with tuberculosis and the ${\Delta}$ logKR continuously decreased in a 3 and 4 days of whole blood culture. Conclusion : The in vitro bactericidal assay by human whole blood culture model was settled using a CFU assay. However, the host immunity to M. tuberculosis was not apparent in the human whole blood culture bactericidal assay, and patients with tuberculosis showed markedly improved bacterial killing after anti-tuberculous chemotherapy compared to before. The simplicity of a whole blood culture facilitates its inclusion in a clinical trial and it may have a potential role as a surrogate marker in a TB vaccine trial.

Thinking in Terms of East-West Contacts through Spreading Process of Sarmathia-Pattened Scabbard on Tillya-Tepe Site in Afghanistan (아프가니스탄 틸랴 테페의 사르마티아(Sarmathia)식 검집 패용 방식의 전개 과정으로 본 동서교섭)

  • Lee, Song Ran
    • Korean Journal of Heritage: History & Science
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    • v.45 no.4
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    • pp.54-73
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    • 2012
  • In this article, we examined the patterns of activities of the Sarmathians though in a humble measure, with a focus on the regions where the Sarmathian sheaths spreaded. One of the main weapons the mounted nomads like the Scythias, the Sarmathians, and the Alans used at war was a spear. Though complementary, a sword was the most convenient and appropriate weapon when fighting at a near distance, fallen from the horse to the ground. The Sarmathian swords continued the tradition of the Akinakes which the Scythias or the Persians used, but those of the Sarmathians showed some advances in terms of the easiness with which a sword was drawn out from a sheath, and the way the sheaths were worn to parts of a human body. It turns out that the Sarmathian sheaths, which were designed for the people to draw swords easily, having the sheaths attached to thighs through 4 bumps, spread extensively from Pazyryk, Altai, to South Siberia, Bactria, Parthia and Rome. The most noteworthy out of all the Sarmathian sheaths were the ones that were excavated from the 4th tomb in Tillatepe, Afghanistan which belonged to the region of Bactria. The owner of the fourth tomb of Tilla-tepe whose region was under the control of Kushan Dynasty at that time, was buried wearing Sarmathian swords, and regarded as a big shot in the region of Bactria which was also under the governance of Kushan Dynasty. The fact that the owner of the tomb wore two swords suggests that there had been active exchange between Bactria and Sarmathia. It seemed that the reason why the Sarmathians could play an important role in the exchange between the East and the West might have something to do with their role of supplying Chinese goods to Silk Road. That's why we are interested in how the copper mirrors of Han Dynasty, decoration beads like melon-type beads, crystal beads and goldring articulated beads, and the artifacts of South China which produced silks were excavated in the northern steppe route where the Sarmathians actively worked. Our study have established that the eye beads discovered in Sarmathian tomb estimated to have been built around the 1st century B.C. were reprocessed in China, and then imported to Sarmathia again. We should note the Huns as a medium between the Sarmathians and the South China which were far apart from each other. Thus gold-ring articulated beads which were spread out mainly across the South China has been discovered in the Huns' remains. On the other hand, between 2nd century B.C. and 2nd century A.D. which were main periods of the Sarmathians, it was considered that the traffic route connecting the steppe route and the South China might be West-South silk road which started from Yunnan, passed through Myanmar, Pakistan, and Afghanistan, and then went into the east of India. The West-south Silk road is presumed to have been used by nomadic tribes who wanted to get the goods from South China before the Oasis route was activated by the Han Dynasty's policy of managing the countries bordering on Western China.