• Title/Summary/Keyword: Hg

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Contents of Mercury, Methylmercury, and Selenium in Deep-Sea Fishes (심해성 어류의 수은, 메틸수은 및 셀레늄 함량)

  • Yun-Sik Cho;Seon-Il Hwang;Sang-Woon Shin;Hyun-Ju Kim;Ji-Yeon Lee;Ji-Won Song;Jeong-Eun Kim;Byoung-Hoon Lee;A-Ra Mo;Myeong-Ki Park
    • Journal of Food Hygiene and Safety
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    • v.38 no.3
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    • pp.158-163
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    • 2023
  • This study aimed to determine mercury (Hg), methylmercury (MeHg), and selenium (Se) levels in deep-sea fishes distributed in Gyeonggi-do, South Korea. Concentrations of Hg, MeHg, and Se were measured by using a mercury analyzer and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). The average content (mg/kg) in the seafood samples was as follows: Hg, 0.7647 (0.0182-5.3620), MeHg, 0.0764 (0.0096-0.8750), and Se, 0.4728 (0.1075-3.5100). All the levels of MeHg were below the recommended standards of the Ministry of Food and Drug Safety i.e., <1.0 mg/kg. Recent studies have shown that Se prevents Hg toxicity. The average daily intake in humans was 3.3 ㎍/kg, which was lower than the recommended amount (50-200 ㎍/person/day). The weekly intake of Hg and MeHg was calculated to be 6.07% and 1.90%, respectively, of the provisional tolerable weekly intake (PTWI). This study showed that the weekly intake of Hg and MeHg from abyssal fish was less than the PTWI recommended by the Joint FAO/WHO expert committee on food additives. Therefore, the levels reported in this study are presumed to be adequately safe.

Disign of $Hg_{1-x}Cd_xTe$ OMVPE System and ARIIV Reactor Chamber ($Hg_{1-x}Cd_xTe$ OMVPE System 과 ARIIV Reactor Chamber의 설계 및 제작)

  • ;J.D. Parsons
    • Journal of the Korean Vacuum Society
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    • v.2 no.4
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    • pp.410-415
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    • 1993
  • The direct growth OMVPE system, designed specificallyfor direct growth of Hg1-xCdxTe using annular rectant inlet inverted verticla (ARIIV) reactor, was constructed. This paper presents the detailed technical approach on a newly designed ARIIV reactor that increases Hg incorporation, imposes uniformity, and avoids the needs for temperature processing to create alloys by inter diffusion approach.

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A Study on the Phase Identification of Dental Amalgams (의과용 아말감의 합금상 판별에 관한 연구)

  • 이규환;신명철
    • Journal of Biomedical Engineering Research
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    • v.2 no.1
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    • pp.39-46
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    • 1981
  • Microstructural phases of the dental amalgams have been studied by optical microscope, scanning electron microprobe and X-ray diffractometer. r1 ($Ag_2Hg_3$) phase and r2 ($Sn_{7-8}Hg$) phase are found on conventional compositioned alloys. On high copper single compositioned alloy, rl ($Ag_2Hg_3$) phase and V ($Cu_6Sn_5$) phase are found but brittle r2 ($Sn_(7-8)Hg$) phase.

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Evaluation of the Potential of Retrograde Flow Competition in the Right Gastroepiploic Artery Graft for Coronary Artery Bypass Grafting (우위대망동맥을 이용한 관상동맥우회술 후 역행성 혈류 발생가능성의 연구)

  • Chung, Bong-Kyu;Sun, Kyung;Kwon, Joon;Kim, Kwang-Ho;Jung, Jae-Seung;Son, Ho-Sung;Lee, Sung-Ho;Kim, Kwang-Taik;Kim, Hyung-Mook
    • Journal of Chest Surgery
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    • v.35 no.1
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    • pp.20-26
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    • 2002
  • Background: Due to the concern of flow competition or retrograde steal, it has been generally suggested that the right gastroepiploic artery(RGEA) pedicled graft should be used in critical coronary stenosis lesion. The study was designed to evaluate the potential of retrograde flow competition in the RGEA pedicled graft by measuring the native pressure differences(PD) between the normal coronary artery and celiac arterial pressure, which would be compared with trans-stenosis pressure gradients(TSPG) in coronary artery occlusive disease. Material and Method: Between July, 1998 and February, 1999, pressures of the right coronary artery and the right gastroepiploic artery(or the celiac artery) were measured in patients with the patent right coronary artery(n=12). The PD between the arteries was compared with the TSPG in the occlusive coronary arteries(n=32). Result: The pressures of the normal right coronary artery and celiac artery were 143$\pm$23 vs. 134$\pm$17mmHg in systole(p<0.005), 74$\pm$13 vs. 73$\pm$14mmHg in diastole(p=NS), and 100$\pm$16 vs. 97$\pm$15mmHg in mean (p<0.05). The PD between the arteries were -8~25mmHg in systole, -4~7mmHg in diastole, and -1~10mmHg in mean. The TSPG measured in the occlusive coronary arteries were -4~19(7$\pm$5.8)mmHg in the lesion less than 75% stenosis vs. 7~74(27$\pm$18.3)mmHg in the 75% or over stenosis lesion(p<0.005). The normally existing pressure difference between the coronary arteries and RGEA(15~20mmHg) was significantlyless than the TSPG in .the occlusive coronary artery with 75% or over stenosis(p<0.001). Conclusion: If the pressure gradient between the RGEA and the coronary artery distal to the stenosis is the main determinant of development of retrograde flow competiton in the RGEA pedicled graft, the above data suggests that there will be little chance of competition when It is used in the coronary lesion with 75% or over stenosis.

Association of Metabolic syndrome, Metabolic syndrome score and Pulse pressure in Korean Adults: Korea National Health and Nutrition Survey, 2012 (한국 성인에서 대사증후군 및 Metabolic syndrome score와 맥압의 관련성-2012 국민건강영양조사에 근거하여)

  • Park, Sun-Young;Yoon, Hyun;Oh, Hye-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.9
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    • pp.5660-5667
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    • 2014
  • The aim of this study was to assess the association of metabolic syndrome, metabolic syndrome score (MSS) and pulse pressure (PP) in Korean adults. The study subjects were Korean adults 20 years or older (n=5,889) who participated in the Korea National Health and Nutrition Examination Survey 2012. After adjusting for factors, such as year and gender and BMI, the mean PP increased with increasing MSS (MSS 0, $41.30{\pm}0.34mmHg$ and MSS 1, $42.16{\pm}0.31mmHg$ and MSS 2, $44.73{\pm}0.34mmHg$ and MSS, 3, $46.46{\pm}0.42mmHg$ and MSS 4, $48.62{\pm}0.58mmHg$ and MSS 5, $53.50{\pm}1.05mmHg$), and the mean PP for metabolic syndrome($47.25{\pm}0.34mmHg$) increased in comparison to Non-Metabolic syndrome ($42.77{\pm}0.19mmHg$). When logistic regression analysis was performed, the odds ratio (OR) of Hyper-PP (61> PP) for MSS 0 was 4.49 in MSS 1 (95% confidence interval[CI], 2.68-7.57) and 8.01 in MSS 2 (95% CI, 4.77-13.47) and 11.37 in MSS 3 (95% CI, 6.67-19.35) and 19.69 in MSS 4 (95% CI, 11.20-34.60) and 34.07 in MSS 5 (95% CI, 17.44-66.52), metabolic syndrome was associated with an increased Hyper-PP(OR 4.6, 95% CI, 2.0-10.4). Conclusion. These results suggest that an increase in MSS or metabolic syndrome might increase the pulse pressure.

Changes in Anxiety and Vital Signs of Scaling Patients (스케일링 전과 후의 불안 및 Vital Sign 변화)

  • Kim, Hae-Sun;Han, Ji-Youn;Hwang, Ji-Min
    • The Journal of the Korea Contents Association
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    • v.17 no.6
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    • pp.396-407
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    • 2017
  • The purpose of this study was to investigate the changes in the vital signs and anxiety reactions during scaling to patients who had received the dental hygiene treatment at department of Dental Hygiene in a university. A total of 189 patients were participated in the study. The level of anxiety was assessed through a dental anxiety questionnaire consisting of dental fear survey scale and dental anxiety survey scale. The vital signs were measured before and after scaling. The obtained results were as follows. The level of anxiety before scaling was 2.16 and after scaling was 1.96. This was significantly higher in women. The pulse and systolic blood pressure after scaling significantly decreased from 77.48 times to 74.36 times per minute and from 124.96 mmHg to 122.50 mmHg respectively. These changes are within the normal physiological variations. Individual changes in respiration, pulse, blood pressure, body temperature are affected by age, gender and previous dental experience, but previous scaling experience. The level of anxiety was significantly explained by respiration before scaling and pulse after scaling. As a result, scaling was associated with dental anxiety reactions and changes in vital signs.

Preliminary Measurements of Mercury Exchange Rates Across the Soil-Air Boundary in a Residential Area of Seoul (토양-대기의 수은 교환작용 -서울시 주거지역에 대한 예비측정-)

  • 김기현;김민영
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.4
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    • pp.369-377
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    • 1998
  • To examine various aspects of Hg exchange processes, we measured Hg$^{\circ}$concentration gradients over soil surfaces in a residential area of Seoul during Sept. 1997. From these measurements, we found that Hg$^{\circ}$concentrations in lower(20 cm) and upper(200 cm) levels varied in the range of 3.15~14.38 (5.30$\pm$1.88: N=236) and 2.07~15.10ng/m$^3$(4.06$\pm$1.69: N=236), respectively. When our data were divided into emission and dry deposition, emission of Hg$^{\circ}$was overwhelmingly dominant (up to 98% in frequency) over dry deposition. The concentration gradients for emission and deposition events were 1.29$\pm$0.86(N=231) and -1.0$\pm$1.27ng/m$^3$(N=5), respectively. The observation of excessively high concentrations in both levels and development of strong gradients suggest that our study site be greatly affected by certain pollution sources of mercury. In face, those data were quite comparable to that had previously been observed from highly contaminated soil environs of Tennessee, USA. To provide some insights into the processes governing the Hg$^{\circ}$exchange processes, we have conducted correlation analyses between Hg$^{\circ}$data and other concurrently determined meteorological plus chemical data. In general, Hg$^{\circ}$concentrations of both levels exhibited similarly the existence of strong correlations with parameters like windspeed, temperature, and relative humidity. Although its concentration gradient data showed similarly strong correlations with meteorological parameters, they showed somewhat unique patterns in that their correlations with Hg$^{\circ}$concentration were noticeably stronger for the lower level than the upper level. To provide rough estimates of Hg$^{\circ}$fluxes in this study, we computed its flux using our gradient data and the predicted K values from previous studies. According to this approach, Hg$^{\circ}$emissions were generally in the range of 103$\pm$80(N=231), while its depositions, being scarcely found, were on the similar magnitude of -92$\pm$128ng/m$^2$/hr(N=5). The findings of excessive emission of Hg$^{\circ}$in residential area of Korea suggests that contamination of mercury be a significant process and hence be dealt more seriously.

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Effect of Green Tea and Coffee Drinking after Meal on the Postprandial Fall of Blood Pressure in Elderly Person with Postprandial Hypotension (식후저혈압 노인에서 식후의 녹차와 커피 섭취가 혈압하강에 미치는 효과)

  • Son, Jung Tae
    • 한국노년학
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    • v.36 no.4
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    • pp.1141-1155
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    • 2016
  • The purpose of this study was to compare the preventive effects of green tea and coffee drinking on postprandial hypotension in the elderly. A total of 30 women ($81.2{\pm}6.8years$) who had experience of postprandial hypotension participated 3 interventions by random order allocation. During the experimental interventions, each participant had a cup of instant coffee (60mg caffeine), or green tea (15.8mg caffeine) after lunch, and control group had only their lunch. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured with 15 minute interval from 30 minutes before the meal to 120 minutes after the meal. The preprandial SBP and DBP were not significantly different between three groups. Postprandial SBP reduction measured at the 1 hour after meal was significantly smaller in coffee group compared to the control group, whereas green tea group was not ($-15.1{\pm}17.9mmHg$ vs $-13.4{\pm}22.4mmHg$ vs. $-4.1{\pm}18.6mmHg$ for control, green tea, and coffee group, respectively, p=.032). Likewise, DBP decrement at the 1 hour after meal was significantly smaller in coffee than control group ($-12.8{\pm}13.0mmHg$ vs $-6.9{\pm}16.6mmHg$ vs $-0.8{\pm}13.4mmHg$ respectively, p=.033). The HR response of the three groups were not significantly different throughout the intervention. Coffee drinking was potentially beneficial for preventing postprandial hypotension and resultant falling event.

Heart-Lung Transplantation in a Patient with VSD, PDA and Eisenmenger′s Syndrome (심실 중격 결손과 동맥관 개존증을 동반한 아이젠멩거 증후군 환자에서의 심장-폐이식 수술 -1예 보고-)

  • 홍유선;김도형;함석진;이교준;이두연;권혁문;김형중;조상호;백효채
    • Journal of Chest Surgery
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    • v.36 no.6
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    • pp.418-421
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    • 2003
  • Heart-lung transplantation is a widely accepted treatment for Eisenmenger'syndrome. The patient is a 41-years-old male diagnosed with Eisenmenger'syndrome due to patent ductus arteriosus. The pressures were checked as follows: aorta 130/80 mean 100 mmHg, pulmonary artery 130/80 mean 109 mmHg, and right ventricle 130/20 mmHg, right atrium mean 20 mmHg. The patient needed heart-lung transplantation due to enlarged right pulmonary artery (diameter 7.5 cm). The donor was a 24 years-old male diagnosed as brain death due to subdural hematoma. Ligation of patent ductus arteriosus was performed under the cardiopulmonary bypass followed by heart-lung transplantation. Patient was extubated on postoperative day one, transferred to the general ward on day 3, and was discharged on postoperative day 33. Cardiac and lung biopsy was performed on postoperative day 41 with no signs of rejection.

A Highly Selective Mercury(II) Ion-Selective Membrane Sensor (고 선택성 수은(II) 이온 막 센서)

  • Ensafi, Ali A.;Meghdadi, S.;Allafchian, Ali R.
    • Journal of the Korean Chemical Society
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    • v.51 no.4
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    • pp.324-330
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    • 2007
  • A new ion selective PVC membrane electrode is developed as a sensor for mercury(II) ions based on bis(benzoylacetone) propylenediimine (H2(BA)2PD) as an ionophore. The electrode shows good response characteristics and displays, a linear Emf vs. log[Hg2+] response over the concentration range of 1.0×10-6 to 1.0×10-1 M Hg(II) with a Nernstian slope of 29.8±0.75 mV per decade and with a detection limit of 2.2×10-7 M Hg(II) over the pH range of 2.5-11.5. Selectivity concentrations for Hg(II) relative to a number of potential interfering ions were also investigated. The sensor is highly selective for Hg(II) ions over a large number of cations with different charge. The sensor has been found to be chemically inert showing a fast response time of 60 s and was used over a period of 3 months with a good reproducibility (S = 0.27 mV). The electrode was successfully applied to determine mercury(II) in real samples with satisfactory results.