• 제목/요약/키워드: pH study

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흉수의 pH 측정에서 혈액가스분석기계, pH meter, pH Strip 방법의 비교 (Comparision of Blood Gas Analyser, pH Meter and pH Strip Methods in the Measurement of Pleural Fluid pH)

  • 지현석;박용범;최재철;안창혁;유지훈;김재열;박인원;최병휘
    • Tuberculosis and Respiratory Diseases
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    • 제48권5호
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    • pp.773-780
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    • 2000
  • 연구배경 : 흉수의 pH 측정은 흉막천자시 흉수의 원인 진단을 위해 시행되는 중요한 검사항목이며, 특히 부폐렴흉막염이 농흉화되는지를 확인할 수 있는 지표중 하나이다. 흉수의 pH 측정은 혈액가스분석기계를 이용하는 것이 표준이나, 상황에 따라서는 pH meter나 pH strip을 이용하기도 한다. 본 연구에서는 흉수중 삼출액을 대상으로 위의 세가지 방법으로 pH를 측정하고 측정치들을 비교하여 보았다. 방법 : 1999년 8월부터 2000년 3월까지 중앙대학교 부속 용산의료원에 입원하여 삼출성 흉수로 의심되어 흉막 천자를 시행한 34례 (결핵성 흉막염 16명, 부폐렴성 흉수 9명, 폐암 5명, 농흉 3명, 심부전 1명)의 흉수에서 혈액가스분석기계, pH meter, pH strip의 세 가지 방법으로 pH를 측정하였다. 혈액가스분석기계와 pH meter에 의한 측정은 천자후 $0^{circ}C$로 유지하면서 30분 내에 시행하였으며, pH strip 측정은 흉막천자 직후에 pH strip으로 pH를 측정하고, 상온 상태로 검사실에 내려서 보고되는 결과를 이용하였다. 결과 : 34례 흉수의 pH 값 (평균값$\pm$표준편차)은 혈액가스 분석법 7.34$\pm$0.12, pH meter 법 7.52$\pm$0.25, pH strip 법 중, 흉막천자후 즉시검사의 경우에는 7.37$\pm$0.16 였으며, 검사실에서 측정한 pH strip법은 6.93$\pm$0.20으로, 혈액가스분석법을 기준으로 한 평균치 분석에서 검사실에서 측정한 pH strip 법은 의미있는 차이를 보였다(p<0.05). 혈액가스분석법과 pH meter 방법, 그리고 혈액가스 분석법과 천자직후 pH strip법의 사이에는 의미있는 상관관계가 있었고, 혈액가스분석법과 pH strip 법 사이에는 의미있는 상관관계가 없었다. 결론 : 흉수천자 직후에 측정한 pH strip 법은 비교적 간단하고 정확하게 흉수의 pH를 측정할 수 있을 것으로 판단된다.

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건강한 성인에서 피부 산도와 영양소 섭취 및 식사패턴과의 상관성 연구 (A Study on the Relationship of Skin Surface pH with Nutrient Intake or Dietary Pattern in Healthy Adults)

  • 강혜진;김건표;조윤희
    • 한국식품영양학회지
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    • 제30권1호
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    • pp.9-18
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    • 2017
  • As an indicator of skin health, acidified skin surface pH ranging from 5 to 7 is crucial for maintaining skin barrier. In this study, we evaluated the relationship between skin pH and dietary pattern (DP) as well as nutrient or food intake in 48 healthy middle aged adults. Skin pH was measured in the skin surface of the inner arm, and blood lipid profile was analyzed. Dietary intake data were obtained using 1 day 24 hour recall method, and DP was extracted using factor analysis. Results revealed that skin pH ranged from 5.15 to 6.88 in all subjects. There was no significant difference in skin pH between males and females. When subjects were grouped by tertile of skin pH, the food intake of fruit, and the nutrient intake of omega 6 fatty acid, potassium, vitamin A, vitamin C, ${\beta}$-carotene, and riboflavin in the first tertile group with skin pH ranging from 5.15 to 5.68 were significantly higher than in the third tertile group with skin pH ranging from 6.26 to 6.88. There was no difference in blood lipid profile between the first and the third tertile group. Among 5 DP extracted by factor analysis, DP5 characterized by a high intake of nuts and fruits as well as a low intake of beverages and alcohol was inversely correlated with skin pH after adjusting for gender and age. DP5 was positively correlated with nutrient intake of carbohydrate, fiber, potassium, iron, vitamin A, vitamin C, ${\beta}$-carotene, thiamine, and riboflavin but negatively correlated with sodium after adjusting for gender, age, smoking, and energy intake. Therefore, acidified skin pH could be maintained by these DP and nutrients.

갈조류 톳의 포복지 재활용을 위한 친환경적 해적생물 구제: pH와 염분 (Environmentally Friendly Phytal Animal Removal for Re-use of Holdfasts of Sargassum fusiforme (Harvey) Setchell: pH and Salinity)

  • 황은경;유호창;김세미;유현일;백재민;박찬선
    • 환경생물
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    • 제32권4호
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    • pp.306-310
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    • 2014
  • 본 연구에서는 톳 양식에서 pH 및 염분농도의 조절에 의한, 환경친화적인 해적생물 구제 방법을 개발하고자 하였다. 이를 위하여 톳의 내성범위를 구하고, 친환경적인 해적생물 구제법을 확립하고자 하였다. 톳에는 생리적 영향을 미치지 않는 친환경적인 해적동물 구제법으로서, pH 4 이하 조건과 pH 10 이상의 조건, 염분농도 10 psu 이하의 조건 및 44 psu 조건에서 효과가 있는 것으로 나타났다.

산성 pH 충격 스트레스에 의한 스트랩토마이세스 시에리컬러 M511의 프로디지닌 생산 증대 (Enhanced Prodiginines Production in Streptomyces coelicolor M511 by Stress of Acidic pH Shock)

  • 모상준
    • 한국미생물·생명공학회지
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    • 제38권3호
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    • pp.273-277
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    • 2010
  • 운데실프로지닌과 스트래토루빈 B는 S. coelicolor가 생산하는 붉은색 항생물질이다. 이번 연구에서 이들 붉은색 항생제의 생산성과 pH shock 스트레스와의 상관관계를 연구 하였다. 운데실프로디지닌과 스트랩토루빈 B의 생합성은 고체 R2YE 배지에서 산성 pH shock에 의해 증가되었다. 최적 pH shock은 pH 4로 비교군과 비교하여 각각 1.6배 및 2배 운데실프로디진과 스트랩토루빈 B의 생산성이 증가되었다. 게다가, 산성 pH 4의 세포 추출물은 T. mentagrophytes 에 대한 주목할만한 저항 활성을 나타내었다. 그러나, 중성 및 염기성 pH shock에서는 이들 항생제의 생산성뿐만 아니라 항진균 활성 증가가 일어나지 않았다. 그러므로, 비록 산성 pH shock이 간단하고 쉬운 방법이지만, 이들 붉은색 항생물질과 다른 이차대사산물의 생산성 향상에는 매우 효과적인 접근방법일 것이다.

우리나라 유산균 제품의 Yeast, Mold 오염에 관한 조사연구 (A Study on Yeast and Mold Contamination of Fermented Milk Products in Korea)

  • 홍종해
    • 한국환경보건학회지
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    • 제7권1호
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    • pp.51-57
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    • 1981
  • This Study was carried out to investigate yeast and mold contamination in fermented milk products produced by 9 different domestic manufacturers from October 20. to December 5. 1980 The results obtained in the study were as follows 1) pH values of the products were ranged from pH 3.14 to pH 4.20 and average of sour milk drinks was pH $3.66\pm 0.19$ and fermented milks pH $3.74\pm 0.11$. Therefore the difference of pH average among sour milk drinks and fermented milks was statistically significant. (p<0.01) 2) In case of yeast contamination, yeast was found on all the four producted at the same date. From this result, it seemed that yeast contamination occured during the manufacturing progress. 3) Degree of contamination by the indicator organisms was E. coli positive, 3.7%: over 1,000 yeasts/ml, 14.8% over 10 molds/ml, 0.9%. 4) In the range of over 1,000 yeasts/ml, degree of contamination by yeast was 8.4% in fermented milk and 16.7% in sour milk drink. 5) Yeasts in product C increased to the spoilage number within 5 days and in H increased within 10 days at 5C. At 15$\circ$C, yeast increased to the spoilage number within 15 days in product A.D. 6) It seems that the yeast number of initial contamination should be important than the increase rate as criteria on the fermented Milk products.

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Cu-Zn 금속 합금의 산화.환원 반응에 의한 난분해성 COD처리에 관한 연구 (A Study on the Treatment of Refractory Organics by Redox Reaction of Cu-Zn Metal Alloy)

  • 송주영;박지원;김종화
    • 한국응용과학기술학회지
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    • 제30권1호
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    • pp.166-172
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    • 2013
  • 본 연구는 압연공정에서 발생하는 폐수 중에 함유되어있는 난분해성 COD 물질을 $80{\mu}m$ 두께의 극세사 형태로 제조된 Cu-Zn 금속합금의 산화 작용으로 인하여 발생하는 OH 라디칼을 이용하여 처리하는 방법에 관한 기초 연구이다. OH 라디칼은 유기화합물(RH) 속에 포함된 수소를 수소추출반응(H Abstraction) 또는 탄소와 탄소(C-C)의 불포화 결합에 첨가됨으로써 빠르고 비 선택적인 반응을 수행하는 것으로 알려진 것처럼 난 분해성 유기화합물의 처리에 효과적인 것으로 나타났다. 금속합금 반응 물질은 극세사 형태로 표면적이 넓어서 1회 처리만으로도 수용액의 pH를 평형에 도달하게 하여서 반응 효율성이 높은 것으로 나타났다. COD처리 효율은 중성 pH에 가까운 pH 7, pH 6에서 최고치를 보였으며 산성분위기인 pH 5이하 및 알칼리성 분위기인 pH 8이상에서는 낮은 효율을 보였다. 실제 압연 폐수의 응집 침전을 이용한 COD 처리에서도 redox 반응장치의 유무에 따라 2배 이상의 처리효율의 차이를 보였다.

TORSION IN THE COHOMOLOGY OF FINITE H-SPACES

  • Choi, Young-Gi
    • 대한수학회지
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    • 제39권6호
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    • pp.963-973
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    • 2002
  • We study torsion phenomena in the integral cohomology of finite if-spaces X through the Eilenberg-Moore spectral sequence converging to H*($\Omega$X; Z$_{p}$). We also investigate how the difference between the Z$_{p}$-filtration length f$_{p}$(X) and the Z$_{p}$-cup length c$_{p}$(X) on a simply connected finite H-space X is reflected in the Eilenberg-Moore spectral sequence converging to H*($\Omega$X;Z$_{p}$). Finally we get the following result: Let p be an odd prime and X an n-connected finite H-space with dim QH* (X;Z$_{p}$) $\leq$ m. Then H*(X;Z) is p-torsion free if (equation omitted).tion omitted).

합성폐수 내 인을 제거하기 위한 TiCl4 농도 및 초기 pH 최적조건 도출 (Optimization of TiCl4 Concentration and Initial pH for Phosphorus Removal in Synthetic Wastewater)

  • 신소연;김종호;안종화
    • 한국물환경학회지
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    • 제31권6호
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    • pp.619-624
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    • 2015
  • This study experimentally determined the effect of titanium tetrachloride (TiCl4) concentration ([TiCl4]) (0.25-0.55 mM) and initial pH (3-11) on phosphorus (P) removal in synthetic wastewater (2 mg P/L). The P removal efficiency increased when [TiCl4] increased. The P removal efficiency showed a parabolic trend with an inflection point at pH 7. At the molar ratio of TiCl4 and P>6.2, the P removal efficiency was over 90% and the residual P concentration was less than 0.2 mg/L. Within the design boundaries, the complete P removal could be achieved at 7.0≤initial pH≤8.5 and 0.43≤[TiCl4]≤0.55 mM. The final pH was over 5.8 at initial pH≥7.7 and [TiCl4]≥0.35 mM. The results showed that TiCl4 was effective in P removal in water so that it could be an alternative chemical for P removal.

Characterization of proteases isolated from Kudoa septempunctata

  • Shin, Sang Phil;Zenke, Kosuke;Yokoyama, Hiroshi
    • 대한수의학회지
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    • 제55권3호
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    • pp.175-179
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    • 2015
  • Proteases play important roles in parasite development and host parasite interactions. The protease of Kudoa spp. has been recognized as a key factor of severe proteolysis of fish muscle post-mortem; however, there is little information available regarding the protease of Kudoa (K.) septempunctata, which was recently identified as a cause of food poisoning in humans. The present study was conducted to isolate and characterize proteases to elucidate the type of protease contained in the parasite and determine the optimal pH for protease activity. We confirmed the cysteine protease and metalloprotease produced by K. septempunctata. While the cysteine protease showed optimal activity at pH 5 that decreased rapidly with increasing pH, the optimal activity of metalloprotease was pH 7, and it remained stable from pH 6 to pH 8. These results indicate that the pH of cysteine protease is not proper for fish muscle postmortem, and that metalloprotease can act in human intestines. Overall, the present study provides important information that improves our understanding of the role of protease physiology and the subsequent food poisoning caused by K. septempunctata.

수질제어 및 부식억제제에 의한 상수도관의 내부부식 제어 (Internal Corrosion Control of Drinking Water Pipes by pH and Alkalinity Control and Corrosion Inhibitor)

  • 구성은;우달식;이두진;김주환;안효원;문광순
    • 상하수도학회지
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    • 제20권2호
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    • pp.215-223
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    • 2006
  • The internal corrosion of water distribution systems is the main cause for the problem of the public health threat as well as water leakage in the damaged pipeline, red water, and odor and taste of the tap water. This study was examined the effect of chemicals used for pH and alkalinity control and corrosion inhibitors for producing the optimal corrosion control method. Corrosion study at different pH and alkalinity indicated that these control using alkaline chemicals was effective in corrosion rate, Fe release reduction, but examined to be increased in turbidity and corrosion-by-products(TTHMs) problems. The turbidity was slightly increased, requiring caution in controlling corrosion with $Ca(OH)_2$. At pH 9.0, TTHMs concentration is increased two times corn pared with non-control of pH. Using the pipe which had experienced 28 years of exposure, iron release was decreased with the corrosion inhibitor. Consequently, pH, Alkalinity control method using alkaline chemicals must be complemented by corrosion inhibitor application for efficient corrosion control.