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Study for the Stabilization of Arsenic in the Farmland Soil by Using Steel Making Slag and Limestone (제강슬래그와 석회석을 이용한 비소오염 농경지 토양 안정화 연구)

  • Lee, Min-Hee;Jeon, Ji-Hye
    • Economic and Environmental Geology
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    • v.43 no.4
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    • pp.305-314
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    • 2010
  • The stabilization process using limestone ($CaCO_3$) and steel making slag as the immobilization amendments was investigated for As contaminated farmland soils around Chonam abandoned mine, Korea. Batch and continuous column experiments were performed to quantify As-immobilization efficiency in soil and the analyses using XRD and SEM/EDS for secondary minerals precipitated in soil were also conducted to understand the mechanism of Asimmobilization by the amendments. For the batch experiment, with 3% of limestone and steel making slag, leaching concentration of As from the contaminated soil decreased by 62% and 52% respectively, compared to that without the amendment. When the mixed amendment (2% of limestone and 1% of steel making slag) was used, As concentration in the effluent solution decreased by 72%, showing that the mixed of limestone and steel making slag has a great capability to immobilize As in the soil. For the continuous column experiments without the amendment, As concentration from the effluent of the column ranged from 50 to $80\;{\mu}g/L$. However, with 2% limestone and 1% steel making slag, more than 80% diminution of As leaching concentration occurred within 1 year and maintained mostly below $10\;{\mu}g/L$. Results from XRD and SEM/EDS analysis for the secondary minerals created from the reaction of the amendments with $As^{+3}$ (arsenite) investigated that portlandite ($Ca(OH)_2$), calcium-arsenite (Ca-As-O) and calcite ($CaCO_3$) were main secondary minerals and the distinct As peaks in the EDS spectra of the secondary minerals can be observed. These findings suggest that the co-precipitation might be the major mechanisms to immobilize As in the soil medium with limestone and steel making slag.

Perspective on Rapid and Selective Method for Detecting Microbiology in Dairy Industry: A Review (낙농산업에 필요한 미생물 검사방법과 전망: 총설)

  • Chon, Jung-Whan;Kim, Hyun-Sook;Kim, Hong-Seok;Kim, Dong-Hyeon;Song, Kwang-Young;Yim, Jin-Hyuk;Choi, Dasom;Lim, Jong-Soo;Jeong, Dong-Gwan;Kim, Soo-Ki;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • v.33 no.2
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    • pp.119-127
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    • 2015
  • To date, detection of microbial populations in dairy products has been performed using culture media, which is a time-consuming and laborious method. The recently developed chromogenic media could be more rapid and specific than classical culture media. However, the newly developed molecular-based technology can detect microbial populations with greater rapidity and sensitivity than the classical method involving culture media and chromogenic media. This molecular-based technology could provide various options for monitoring the characterization of different states of bacteria and cells. Thus, it could help upgrade the processing system of the dairy industry so as to maintain the safety and quality of dairy foods. Among the various newly developed molecular-based technologies, flow cytometry can potentially be used for monitoring microbiological populations in the dairy industry if official international standards are available for this purpose. When omics technology would have biomarker identification, it could be regarded as the rapid and sensitive analytical methods. Methods based on PCR, which has become a basic technique in microbiological research, can be developed and validated as alternative methods for quantification of dairy microorganisms. This review discusses methods for monitoring microbiological populations in dairy foods and the limitations of these studies, as well as the need for further research on such methods in the dairy industry.

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Immunoglobin G Antibodies to Purified-Protein-Derivative and Lipoarabinomannan-B by Enzyme-Linked Immunosorbent Assay in the Diagnosis of Tuberculous Pleural Effusion (결핵성 흉막염 환자에 있어서 효소결합 면역분석법으로 측정한 Purified-Protein-Derivative와 Lipoarabinomannan-B에 대한 Immunoglobulin G 항체의 진단적 가치에 관한 연구)

  • Moon, Tai-Hoon;Cho, Chul-Ho;Kwak, Seung-Min;Kim, Jin-Ju;Cho, Sang-Nae
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.4
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    • pp.455-464
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    • 1995
  • Background: Considering that both humoral and cell mediated immunities play an important role for human tuberculosis infection, enzyme-linked immunosorbent assay(ELISA) measurement of immunoglobulin G (IgG) antibody to mycobacterial antigens can be used for the serologic diagnosis of tuberculous pleural effusion. Method: We measured absorbance values of IgG antibodies to purified-protein-derivative (PPD) and lipoarabinomannan-B (LAM-B) in the pleural fluid (PF) and the serum in 40 tuberculous (TPE) and 19 nontuberculous pleural effusions (NTPE). Results: 1) The IgG antibodies to PPD and LAM-B were significantly (P<0.0005) higher in the PF and the serum of TPE compared to NTPE. 2) The IgG antibodies to PPD and LAM-B in the serum were higher than that in PF. 3) Significant correlations were found between pleural and serum IgG antibodies to PPD and LAM-B. 4) With a cutoff value for IgG antibody to PPD in the PF of 0.091, sensitivity was 55.0% and specificity 94.7% in the diagnosis of TPE. 5) With a cutoff value for IgG antibody to LAM-B in the PF of 0.337, sensitivity was 50.0% and specificity 94.7% in the diagnosis of TPE. 6) The seropositive rates in TPE were not related to PPD skin test status, the amount of PF and coexisting active pulmonary tuberculosis. Conclusion: The assay of IgG antibodies to PPD and LAM-B might be useful for the diagnosis of TPE. Our study suggests the mechanism of passive transfer of IgG antibodies to PPD and LAM-B from the serum to the PF through pleural tissue.

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The Usefulness in an Automated Kinetic Method in Determining of ADA Activity in Pleural Fluid (자동화학분석기를 이용한 흉막액내 ADA 활성치 측정의 유용성에 관한 연구)

  • Ryu, Jeong-Seon;Yong, Suk-Joong;Song, Kwang-Seon;Shin, Kye-Chul;Lee, Won-Sik;Kang, Shin-Ku;Uh, Young;Yoon, Kap-Jun
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.838-845
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    • 1995
  • The determination of ADA(adenosine deaminase) activity in pleural fluid is useful in differental diagnosis of pleural effusion. The conventional method of determining ADA activity used by Giusti was influenced by contamination of ammonia. Additionally, because Giusti's method was mannual method a determining the ADA activities in sample, was not easily automated. In 1993, Oosthuizen HM with collegues developed simple kinetic method for determining ADA activity. It was reliable and suiable method for automation. In this study, we have measured ADA activity in 162 patients with various pleural effusion by Hitachi 747 autoanalyser using the Oosthuizen kinetic method for the purpuse of determination of new diagnostic cut-off value for the tuberculous effusion and evaluation of the correlation between the conventional method and new automated method. This new method of an enzymatic reaction involves 2, 6-dichlorophenolindophenol dye(DICP), adenosine, xanthine oxidase(XO), and nucleoside phosphorylase(NP). The results were as follows: 1) The mean pleural ADA activity of the tuberculous effusion was $52.53{\pm}16.43\;U/L$ and significantly higher than that of other groups(p<0.001). If the diagnostic cut-off value of pleural ADA activity for tuberculous effusion is above 30 U/L, the sensitivity is 96% and the specificity is 90%. 2) The mean pleural to serum ADA activity ratio of the tuberculous effusion was $2.29{\pm}0.96$ and it was also significantly higher than that of other pleural groups(p<0.001). If the diagnostic cut-off value of pleural to serum ADA activity ratio is 1.5, the sensitivity is 80% and the specificity is 88% in the diagnosis of tuberculous pleural effusion. 3) The new kinetic method is correlates well to Giuisti's conventional method(r=0.971). In conclusion, the new kinetic method described is easily automated and seems to be suitable for the routine determination of ADA activity.

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Effect of Temperature and Various Pre-treatments on Germination of Hippophae rhamnoides Seeds (갈매보리수나무 종자의 온도 및 여러 가지 전처리에 따른 발아반응)

  • Choi, Chung-Ho
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.132-141
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    • 2012
  • This study was carried out to test seed germination responses to temperatures and pre-treatments in Hippophae rhamnoides, which has many abilities in antioxidant activity, soil improvement and erosion control. H. rhamnoides seeds were placed at 10, 15, 20, 25, 30 and $35^{\circ}C$ under light condition. As the results, germination percentage (GP) was the highest at 15 and $20^{\circ}C$, and mean germination time (MGT), germination rate (GR) and germination value (GV) were the highest at $25^{\circ}C$. Quadratic and linear regression model were used to determine the cardinal temperatures such as base ($T_b$), maximum ($T_m$) and optimum ($T_o$) temperature for germination. In quadratic regression model using PG, $T_b$, $T_m$ and $T_o$ was estimated as 0.6, 36.4 and $18.5^{\circ}C$, respectively, and temperature range for germination was $35.8^{\circ}C$. In linear regression model using GR, $T_b$, $T_m$ and $T_o$ was estimated as 8.3, 35.4 and $25.3^{\circ}C$, respectively, and temperature range for germination was $27.2^{\circ}C$. Germination properties were investigated after H. rhamnoides seeds were treated by prechilling (1, 2, 4, 6 and 8 weeks), stratification (2, 4, 6 and 8 weeks), solid matrix priming (seed : carrier : water = 5 : 1 : 7, 8, 9 and 10), osmo-priming (-0.25, -0.5, -1.0 and -1.5 MPa) and calcium chloride ($CaCl_2$) -priming (100, 200, 300 and 400 mM). The highest GP was observed in $CaCl_2$ 300 and 400 mM treatments, and MGT was the shortest in stratification 6 and 8 weeks treatments. GR and GV were the highest and GP was the second highest when seeds were prechilled for 1 and 2 weeks. Consequently, prechilling 1 or 2 weeks treatment was considered as the appropriate method when we contemplate qualitative and quantitative effects in seedling production.

Time-Lapse Crosswell Seismic Study to Evaluate the Underground Cavity Filling (지하공동 충전효과 평가를 위한 시차 공대공 탄성파 토모그래피 연구)

  • Lee, Doo-Sung
    • Geophysics and Geophysical Exploration
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    • v.1 no.1
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    • pp.25-30
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    • 1998
  • Time-lapse crosswell seismic data, recorded before and after the cavity filling, showed that the filling increased the velocity at a known cavity zone in an old mine site in Inchon area. The seismic response depicted on the tomogram and in conjunction with the geologic data from drillings imply that the size of the cavity may be either small or filled by debris. In this study, I attempted to evaluate the filling effect by analyzing velocity measured from the time-lapse tomograms. The data acquired by a downhole airgun and 24-channel hydrophone system revealed that there exists measurable amounts of source statics. I presented a methodology to estimate the source statics. The procedure for this method is: 1) examine the source firing-time for each source, and remove the effect of irregular firing time, and 2) estimate the residual statics caused by inaccurate source positioning. This proposed multi-step inversion may reduce high frequency numerical noise and enhance the resolution at the zone of interest. The multi-step inversion with different starting models successfully shows the subtle velocity changes at the small cavity zone. The inversion procedure is: 1) conduct an inversion using regular sized cells, and generate an image of gross velocity structure by applying a 2-D median filter on the resulting tomogram, and 2) construct the starting velocity model by modifying the final velocity model from the first phase. The model was modified so that the zone of interest consists of small-sized grids. The final velocity model developed from the baseline survey was as a starting velocity model on the monitor inversion. Since we expected a velocity change only in the cavity zone, in the monitor inversion, we can significantly reduce the number of model parameters by fixing the model out-side the cavity zone equal to the baseline model.

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Development and Evaluation of Silicon Passive Layer Dosimeter Based Lead-Monoxide for Measuring Skin Dose (피부선량 측정을 위한 Lead-Monoxide 기반의 Silicon Passive layer PbO 선량계 개발 및 평가)

  • Yang, Seung-Woo;Han, Moo-Jae;Jung, Jae-Hoon;Bae, Sang-Il;Moon, Young-Min;Park, Sung-Kwang;Kim, Jin-Young
    • Journal of the Korean Society of Radiology
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    • v.15 no.6
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    • pp.781-788
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    • 2021
  • Due to the high sensitivity to radiation, excessive exposure needs to be prevented by accurately measuring the dose irradiated to the skin during radiation therapy. Although clinical trials use dosimeters such as film, OSLD, TLD, glass dosimeter, etc. to measure skin dose, these dosimeters have difficulty in accurate dosimetry on skin curves. In this study, to solve these problems, we developed a skin dosimeter that can be attached according to human flexion and evaluated its response characteristics. For the manufacture of the dosimeter, lead oxide (PbO) with high atomic number (ZPb: 82, ZO: 8) and density (9.53 g/cm3) and silicon binders that can bend according to human flexion were used. In the case of a dosimeter made of PbO material, the performance degradation has been prevented by using parylene and others due to the presence of degradation due to oxidation, but the previously used parylene is affected by bending, so a new form of passive layer was produced and applied to the skin dosimeter. The characteristic evaluation of the skin dosimeter was evaluated by analyzing SEM, reproducibility, and linearity. Through SEM analysis, bending was evaluated, reproducibility and linearity at 6 MeV energy were evaluated, and applicability was assessed with a skin dosimeter. As a result of observing the dosimeter surface through SEM analysis, the parylene passive layer PbO dosimeter with the positive layer raised to the parylene produced cracks on the surface when bent. On the other hand, no crack was observed in the silicon passive layer PbO dosimeter, which was raised to silicon passive layer. In the reproducibility measurement results, the RSD of the silicon passive layer PbO dosimeter was 1.47% which satisfied the evaluation criteria RSD 1.5% and the linearity evaluation results showed the R2 value of 0.9990, which satisfied the evaluation criteria R2 9990. The silicon passive layer PbO dosimeter was evaluated to be applicable to skin dosimeters by demonstrating high signal stability, precision, and accuracy in reproducibility and linearity, without cracking due to bending.

Production and characterization of rice starch from stale rice using improved enzymatic digestion method (개선된 효소소화법에 의한 고미로부터 쌀전분의 생산 및 특성)

  • Kim, Reejae;Lim, SongI;Kim, Hyun-Seok
    • Korean Journal of Food Science and Technology
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    • v.53 no.6
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    • pp.749-755
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    • 2021
  • The objective of this study was to investigate the physicochemical properties of rice starch extracted from stale rice using alkaline steeping (AKL) and improved enzymatic digestion (iENZ) methods. The crude protein content (0.5-0.7%) of stale rice starch (SRS) was less than 1% by iENZ, but not so when measured by the existing ENZ methods. SRS is an intermediate amylose rice starch. AKL-SRS and iENZ-SRS exhibited typical A-type crystal packing arrangements with similar relative crystallinities. iENZ-SRS showed higher gelatinization onset and peak temperatures with a narrower gelatinization temperature range, compared to those of AKL-SRS, indicating that iENZ annealed SRS. Thus, iENZ-SRS exhibited lower swelling power and solubility, and higher pasting viscosities with delayed viscosity development. Overall, the use of stale rice as a rice starch source could make economical production of rice starch possible, and iENZ may diversify rice starch characteristics, which expands the utilization of rice starch in food and non-food industries.

An Optimization Study on a Low-temperature De-NOx Catalyst Coated on Metallic Monolith for Steel Plant Applications (제철소 적용을 위한 저온형 금속지지체 탈질 코팅촉매 최적화 연구)

  • Lee, Chul-Ho;Choi, Jae Hyung;Kim, Myeong Soo;Seo, Byeong Han;Kang, Cheul Hui;Lim, Dong-Ha
    • Clean Technology
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    • v.27 no.4
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    • pp.332-340
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    • 2021
  • With the recent reinforcement of emission standards, it is necessary to make efforts to reduce NOx from air pollutant-emitting workplaces. The NOx reduction method mainly used in industrial facilities is selective catalytic reduction (SCR), and the most commercial SCR catalyst is the ceramic honeycomb catalyst. This study was carried out to reduce the NOx emitted from steel plants by applying De-NOx catalyst coated on metallic monolith. The De-NOx catalyst was synthesized through the optimized coating technique, and the coated catalyst was uniformly and strongly adhered onto the surface of the metallic monolith according to the air jet erosion and bending test. Due to the good thermal conductivity of metallic monolith, the De-NOx catalyst coated on metallic monolith showed good De-NOx efficiency at low temperatures (200 ~ 250 ℃). In addition, the optimal amount of catalyst coating on the metallic monolith surface was confirmed for the design of an economical catalyst. Based on these results, the De-NOx catalyst of commercial grade size was tested in a semi-pilot De-NOx performance facility under a simulated gas similar to the exhaust gas emitted from a steel plant. Even at a low temperature (200 ℃), it showed excellent performance satisfying the emission standard (less than 60 ppm). Therefore, the De-NOx catalyst coated metallic monolith has good physical and chemical properties and showed a good De-NOx efficiency even with the minimum amount of catalyst. Additionally, it was possible to compact and downsize the SCR reactor through the application of a high-density cell. Therefore, we suggest that the proposed De-NOx catalyst coated metallic monolith may be a good alternative De-NOx catalyst for industrial uses such as steel plants, thermal power plants, incineration plants ships, and construction machinery.

Effect of Aprepitant in Patient with Gastroparesis and Related Disorders (위마비증과 만성 구역 구토 증후군 환자에서 Aprepitant의 효과)

  • Jung, Kyoungwon;Park, Moo In
    • The Korean Journal of Gastroenterology
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    • v.72 no.6
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    • pp.325-328
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    • 2018
  • 위마비증(gastroparesis)이나 만성 구역 구토 증후군(chronic unexplained nausea and vomiting)으로 인한 구역과 구토에 대한 치료는 일반적으로 사용하는 위장관 촉진제에 만족스럽지 못한 경우가 많고, 여러 부작용으로 인하여 장기적으로 사용하기 어려워 보다 효과적인 치료 방법이 필요하다. 최근 미국에서 발표된 본 연구는 위마비증이나 연관 증후군 환자에서 구역과 구토 증상을 줄이기 위한 aprepitant(neurokinin-1 receptor antagonist) 치료의 효과를 분석한 것으로, 향후 일반적인 치료에 불응성 위마비증 환자에서 새로운 약제 사용을 시도해볼 수 있어 소개하고자 한다. 본 Aprepitant for the Relief of Nausea (APRON) 연구는 기질적 질환을 배제하기 위하여 최근 2년 이내 위내시경이 정상이며, 적어도 6개월 이상 조기 포만감(early satiety), 식후 만복감(postprandial fullness), 팽만감(bloating) 그리고 명치부 통증(epigastric pain)을 유발하는 증상과 함께 만성적인 구역이 있는 18세 이상의 성인 중 4시간의 위배출 검사를 시행받은 환자를 대상으로 하였다. 객관적인 지표로 0점에서 45점까지 보이는 9-증상 Gastroparesis Cardinal Symptom Index(GCSI)가 2주 이상 총 21점 이상이며, 0-100 mm의 visual analog scale (VAS)의 7일간의 구역 증상 평균 25 mm 이상인 환자를 대상으로 하였다. 일주일에 3일 이상 narcotics를 사용하였거나 와파린이나 pimozide, terfenadien, astemizole, cisapride를 복용하였던 환자, 2배 이상으로 간 효소 수치상승을 보이거나 Child-Pugh score 10점 이상, aprepitant에 알레르기를 보이는 환자는 제외되었다. 그렇지만 metoclopramide나 erythromycin을 안정적으로 사용 중인 환자는 제외되지 않았다. 위배출 검사는 2시간에서 60% 이상 남아 있거나 4시간에서 10% 이상 남아 있는 경우에 지연된 것으로 정의되었으며, 지연된 위배출 검사 결과 자체는 환자의 등록 기준에 포함되진 않았다. 등록 기준에 포함된 환자는 1:1로 무작위 배정되어 하루 한 번 125 mg의 aprepitant 복용군과 위약군으로 나누어져 연구가 진행되었으며, 약제 복용 4주간 2주 간격으로, 그리고 복용 후 2주 뒤까지 구역 증상의 호전 정도와 약제 안전성을 확인하였다. 이러한 효과를 판정하기 위하여 환자가 방문하는 동안 GCSI를 포함한 Patient Assessment of Upper GI Symptoms (PAGI-SYM), Gastrointestinal Symptom Rating Scale, daily VAS, daily diary version of the GCSI 그리고 정신 측정 도구와 삶의 질 도구인 Patient health Questionnaire 15와 Short Form 36 version이 측정되었다. 구역에 대한 aprepitant와 위약의 치료 효과의 일차적 판정은 이전 항암 요법에 대한 aprepitant 연구와 같이 28일 평균 VAS 25 mm 미만이거나 치료 전 7일간의 VAS와 비교하여 28일 치료 기간 동안 25 mm 이상 감소한 경우로 정의하였고, 이차 결과는 구역의 매일 시간, 치료 중 구역이 없는 날짜의 퍼센트, PAGI-SYM score의 개선 등으로 확인하였다. 2013년 4월부터 2015년 7월까지 총 126명의 환자가 등록되어 aprepitant군 63명, 위약군 63명으로 무작위 배정되었다. 전체의 57%인 72명에서 위배출 지연이 보였으며, 나머지 43%에서는 정상 또는 빠른 위배출 소견을 보여 만성적으로 설명할 수 없는 구역과 구토에 포함된 환자군으로 확인되었다. 또한 29%에서 당뇨를 가지고 있었으며, 8%에서 수면제를 사용하고 있었다. 최종적으로 aprepitant군은 59명, 위약군은 63명이 연구를 끝까지 종료하였다. 일차 결과에서 aprepitant 군 46%, 위약군 40%의 구역 호전을 보여 두 치료군 간에 통계적으로 의미 있는 차이는 보이지 않았다(상대 위험도 1.2, 95% CI: 0.8-1.7; p=0.43). 그러나 일차 분석의 두 가지 척도(28일 평균 VAS 25 mm 미만과 기저 VAS보다 평균 28일 VAS의 25 mm 이상 감소)를 모두 함께 고려한 민감도 분석에서는 aprepitant군이 37% (22/59)로 위약군의 17%(11/63)에 비하여 통계적으로 의미 있는 구역의 호전을 보였다(상대 위험도 2.1, 95% CI: 1.1-4.1; p=0.01). 또한 이차 분석을 살펴보면 aprepitant군에서 PAGI-SYM 중증도 지수로 확인하였을 때, 구역(1.8 vs. 1.0; p=0.005)과 구토(1.6 vs. 0.5; p=0.001)의 중증도 및 매일 구역 시간의 감소를 보였고, 28일 동안 구역이 없는 날짜의 퍼센트 증가 소견을 보였다. 다른 이차 결과 분석에서 aprepitant군이 PAGI-SYM 중증도 지수의 GCSI 종합 점수(1.3 vs. 0.7; p=0.001), 상당한 증상호전, 구역 구토의 세부 점수, 팽만감 세부 점수 그리고 위식도 역류 증상 점수에서 호전을 보였고, 매일 일기로 표현한 daily diary version of the GCSI에 상복부 통증 중증도, 전체 증상 그리고 Gastrointestinal Symptom Rating Scale의 종합 점수에서 호전을 보였다. 연구 중 발생한 부작용은 주로 경증과 중등도 정도의 부작용이 주로 발생하였지만, aprepitant군(35% vs. 17% 위약군, p=0.04)에서 더 많이 발생하였다. 결론적으로 위마비증 또는 위마비증 유사 증후군으로 인한 만성 구역 및 구토 환자의 무작위 시험에서 aprepitant는 VAS 점수를 통한 주요 결과를 분석하였을 때는 구역의 중증도를 호전시키지 못하였지만 다른 이차적 결과에 대해서는 위약군에 대하여 호전 소견을 보였다. 따라서 aprepitant에 효과적인 반응을 보이는 위마비증 환자를 감별하는 추가 임상시험이 필요할 것으로 판단된다.