• Title/Summary/Keyword: Injection Period

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Effect of DEHP Administration on Reproduction in Pregnant Mice Ⅱ. Effect of DEHP Administration on Reproductive Characteristic and Blood Components in Pups Born after DEHP Administration in Pregnant Mice (임신중인 생쥐에 DEHP 투여가 번식현상에 미치는 영향 Ⅱ. 임신중인 생쥐에 DEHP 투여가 자손의 번식특성과 혈액성분에 미치는 영향)

  • Park, Dong-Heon;Jang, Hyun-Yong;Park, Choon-Keun;Cheong, Hee-Tae;Kim, Choung-Ik;Yang, Boo-Keun
    • Development and Reproduction
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    • v.8 no.2
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    • pp.91-97
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    • 2004
  • The objective of this study was to assess that the effects of DEHP administration on reproductive characteristics and blood hematological and chemical values in pups born after DEHP administration in pregnant mice. DEHP was administrated to pregnant mice by intraperitoneally injection with 0, 0.5, 1.0 and 10.0mg/kg B.W, 5 times at 3 days interval from Day 1 to Day 16 in the gestation period. The body weight and reproductive organ weight(testis, epididymis and coagulating gland) in male pups on 45 day after birth was not affected in all experimental groups, but vesicular gland in DEHP groups was significantly lower than that of control group(P<0.05). The semen characteristics of male pups were not affected in DEHP treatment groups. The WBC, HB, HT, MCH and albumin values in male pups were not affected in all experimental groups, but RBC MCV, MCHC, PLT and total protein values were significantly different among the experimental groups(P<0.05). In female pups, the effects of DEHP administration were not affected the body and uterus weight, but the left ovary in 10.0mg DEHP group was significantly heavier than in control and 0.5mg DEHP group(P<0.05). The WBC, MCV, MCH, MCHC, PLT, albumin, BUN and total protein values in female were not different in all experimental groups. The RBC, HB and HT values were significantly different among the experimental gruop(P<0.05). The historical evaluation of testis in male pups that were grown to 45 days after birth was not different in all experimental groups. The ovary in female pups had many corpus luteum in 10.0mg DEHP group. The endometriosisi of uterus was significantly decreased in DEHP group. There results suggest that low concentration of DEHP administration in pup born after DEHP administration in pregnant mice was not affered on reproductive characteristic, but was affected on blood hematological and chemical values.

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Geomicrobiological Behavior of Heavy Metals in Paddy Soil Near Abandoned Au-Ag Mine Supplied with Carbon Sources (탄소원을 공급한 폐금은광산 주변 논토양 내 중금속의 지구미생물학적 거동 연구)

  • Ko, M.S.;Lee, J.U.;Park, H.S.;Shin, J.S.;Bang, K.M.;Chon, H.T.;Lee, J.S.;Kim, J.Y.
    • Economic and Environmental Geology
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    • v.42 no.5
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    • pp.413-426
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    • 2009
  • The study was conducted to investigate the effects of indigenous bacteria on geochemical behavior of toxic heavy metals in contaminated paddy soil near an abandoned mine. The effects of sulfate amendment to stimulate microbial sulfate reduction on heavy metal behaviors were also investigated. Batch-type experiments were performed with lactate or glucose as a carbon source to activate indigenous bacteria in the soil under anaerobic condition for 100 days. Sulfate (250 mg/L) was artificially injected at 60 days after the onset of the experiments. In the case of glucose supply, solution pH increased from 4.8 to 7.6 while pH was maintained at 7~8 in the lactate solution. The initial low pH in the case of glucose supply likely resulted in the enhanced extraction of Fe and most heavy metals at the initial experimental period. Lactate supply exerted no significant difference on the amounts of dissolved Zn, Pb, Ni and Cu between microbial and abiotic control slurries; however, lower Zn, Pb and Ni and higher Cu concentrations were observed in the microbial slurries than in the controls when glucose supplied. Sulfate amendment led to dramatic decrease in dissolved Cr and maintenance of dissolved As, both of which had gradually increased over time till the sulfate injection. Black precipitates formed in solution after sulfate amendment, and violarite($Fe^{+2}{Ni^{+3}}_2S_4$) was found with XRD analysis in the microbial precipitates. Conceivably the mineral might be formed after Fe(III) reduction and microbial sulfate reduction with coprecipitation of heavy metal. The results suggested that heavy metals which can be readily extracted from contaminated paddy soils may be stabilized in soil formation by microbial sulfate reduction.

Radioprotective Effect of Red Ginseng in Irradiated Mice with ${\gamma}$-ray (생쥐에서 홍삼의 감마선조사에 의한 방어효과)

  • Seung, Ka-Yeon;Lee, Heung-Man;Kim, Jong-Sang;Lee, Jun-Haeng
    • Journal of the Korean Society of Radiology
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    • v.4 no.1
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    • pp.31-35
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    • 2010
  • Recently, the incidents of direct or indirect radiation exposure due to increase of use of radiation or radioisotope are on the increase in medical and industrial circles. If cells are irradiated, free radicals are created through biological process, and cells are directly or indirectly damaged. This research intends to explore into the effect of saponin at the level of cell (in vitro) and entity (in vivo), using red ginseng extract "saponin", as radioprotective agent. In the experiment implemented at the level of cell (in vitro), degree of cell activity was measures by adding mouse mesenchymal stem cells "C3H/10T1/2 cells" into red ginseng extract "saponin(0, 0.05, 0.2, and 0.4 g/L)", and then the optimal concentration of saponin influencing cells was calculated, in 24, 48, 72, and 96 hours after gamma irradiation at the optimal concentration of saponin, each cell survival rate was observed through XTT assay. The best time period of cultivation for the optimal activity of C3H/10T1/2 cells was as 48 hours, and the degree of optimal activity was shown at 0.05 g/L. In 48 hours after irradiation of 5 Gy to C3H/10T1/2 cells at 0.05 g/L, the degree of activity of cells increased by 10%. In the experiment implemented at the level of entity (in vivo), red ginseng extract "saponin" at a dose of 100 mg/kg/day was injected into the abdominal cavity of six-week immature mouse for two weeks. Right after the last abdominal injection, total body irradiation of gamma rays was carried out at a dose of 5 Gy and 10 Gy. And after irradiation, the blood sample was taken, and then the number of red corpuscles was counted. In result, the decrement of experimental group treated with red ginseng extract "saponin" was 2.3 times larger than that of control group. In view of the results so far achieved, it was revealed that red ginseng extract "saponin" has a radiation exposure protection effect in the experiment implemented at the level of cell (in vitro). In case of animal experiment, the decrement of number of red corpuscles decreased. Finally, it is necessary to carry out more various researches continuously.

A Literature Study about Comparison of Eastern-Western Medicine on the Acne (여드름의 동(東)·서의학적(西醫學的) 문헌(文獻) 고찰(考察))

  • Joo, Hyun-A;Bae, Hyeon-Jin;Hwang, Chung-Yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.25 no.2
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    • pp.1-19
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    • 2012
  • Objective : The purpose of this study is to investigate about comparison of Eastern-Western medicine on the acne. Methods : We searched Eastern and Western medicine books for acne. We analyzed these books and examined category, definition, etiology, classification, internal and external methods of treatment of acne. Results : The results were as follows. 1. In Eastern medicine, Acne belongs to the category of the Bunja(粉刺), Jwachang(痤瘡), Pyepungbunja(肺風粉刺). In Western medicine, the other name of Acne is acne vulgaris. 2. In Eastern medicine, the definition of Acne includes manual extraction of comedones and skin appearance. In Western medicine, Acne is a common skin disease during adolescence and a chronic inflammatory disease of pilosebaceous unit of self localization. It is characterized by noninflammatory, open or closed comedones and by inflammatory papules, pustules, and nodules and it affects the areas of skin with the densest population of sebaceous follicles, these areas include the face, neck, back, and the upper part of the chest. 3. In Eastern medicine, the cause and mechanism of Acne arose from the state of internal dampness-heat and spleen-stomach internal qi deficiency due to dietary irregularities and then invaded external pathogen such as wind-dampness-heat-cold-fire in lung meridian lead to qi and blood heat depression stagnation. So it appears in skin. In Western medicine, the etiology and pathogenesis of Acne is clearly not identified, but there are most significant pathogenic factors of blood heat depression stagnation. So it appears in skin. In Western medicine, the etiology and pathogenesis of Acne is clearly not identified, but there are most significant pathogenic factors of Acne; Androgen-stimulated production of sebum, hyperkeratinization and obstruction of sebaceous follicles, proliferation of Propionibacterium acnes and inflammation, abnormaility of skin barrier function, genetic aspects, environmental factors etc. 4. In Eastern medicine, differentiation of syndromes classifies clinical aspects, and cause and mechanism of disease; the former is papular, pustular, cystic, nodular, atrophic, comprehensive type; the latter is lung blood heat, intestine-stomach dampness-heat, phlegm-stasis depression, thoroughfare-conception disharmony, heat toxin type. In Western medicine, it divides into an etiology and invasion period, and clinical aspects; Acne neonatorum, Acne infantum, Acne in puberty and adulthood, Acne venenata; Acne vulgaris, Acne conglobata, Acne fulminans, Acne keloidalis. 5. In Eastern medicine, Internal methods of treatment of Acne are divided into five treatments; general treatments, the treatments of single-medicine and experiential description, the treatments depending on the cause and mechanism of disease, and clinical differentiation of syndromes, dietary treatments. In Western medicine, it is a basic principles that regulation on production of sebum, correction on hyperkeratinization of sebaceous follicles, decrease of Propionibacterium acnes colony and control of inflammation reaction. Internal methods of treatment of Acne are antibiotics, retinoids, hormone preparations etc. 6. In Eastern medicine, external methods of treatment of Acne are wet compress method, paste preparation method, powder preparation method, pill preparation method, acupuncture and moxibustion therapy, ear acupuncture therapy, prevention and notice, and so on. In Western medicine, external method of treatments of Acne are divided into topical therapy and other surgical therapies. Topical therapy is used such as antibiotics, sebum regulators, topical vitamin A medicines etc and other surgical therapies are used such as surgical treatments, intralesional injection of corticosteroids, skin dermabrasion, phototherapy, photodynamic therapy, and so on. Conclusions : Until now, there is no perfect, effective single treatment. We think that Eastern medicine approach and treatment can be helpful to overcome the limitations of acne cure.

Ultrasound-Guided Axillary Brachial Plexus Block, Performed by Orthopedic Surgeons (정형외과 의사가 시행한 초음파 유도 액와 상완 신경총 차단술)

  • Kim, Cheol-U;Lee, Chul-Hyung;Yoon, Ja-Yeong;Rhee, Seung-Koo
    • Journal of the Korean Orthopaedic Association
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    • v.53 no.6
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    • pp.513-521
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    • 2018
  • Purpose: The purpose of this study was to assess the effectiveness and complications of an ultrasound-guided axillary brachial plexus block performed by orthopedic surgeons. Materials and Methods: From March to May 2017, an ultrasound-guided axillary brachial plexus block was performed on a total of 103 cases of surgery. A VF13-5 transducer from Siemens Acuson X300 was used. The surgical site was included in the range of the anatomic sensory distribution of the blocked nerve, except for the case where an operation time of more than 2 hours was expected due to multiple injuries and the operation of the upper arm. The procedure was performed by 2 orthopedic surgeons in the same method using 50 ml of solution (20 ml of lidocaine HCl in 2%, 20 ml of ropivacaine in 0.75%, 10 ml of normal saline in 0.9%). The success rate of anesthesia induction during surgery, anesthetic induction time, anatomical range of operation, duration of postoperative analgesia and complications were investigated. Results: The results from the 2 practices were similar. The anesthesia was successful in 100 out of 103 patients (97.1%). In these patients, the average needling time was 5.5 minutes (2.5-13.2 minutes), the average induction time to complete anesthesia was 18.4 minutes (5-40 minutes), and the average duration of postoperative analgesia was 402.8 minutes (141-540 minutes). The post-anesthesia immediate complications were dizziness in 1 case, nausea and vomiting in 4 cases, and peri-oral numbness in 2 cases, but surgery was performed without problems. All these 7 cases with complications recovered on the same day. A total of 3 cases failed with anesthesia, and they were treated by an injection with local anesthesia in the operation room in 2 cases and switched to general anesthesia in 1 case. Conclusion: An ultrasound-guided axillary brachial plexus block, which was performed by orthopedic surgeons allows anesthesia in a brief period and the high success rates of anesthesia for certain surgeries of the elbow and surgeries on forearm, wrist and hand. Therefore, it can reduce the waiting time to the operating room. This technique is a relatively safe procedure and dose selective anesthesia is possible.

Analysis of Surface Displacement of Oil Sands Region in Alberta, Canada Using Sentinel-1 SAR Time Series Images (Sentinel-1 SAR 시계열 영상을 이용한 캐나다 앨버타 오일샌드 지역의 지표변위 분석)

  • Kim, Taewook;Han, Hyangsun
    • Korean Journal of Remote Sensing
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    • v.38 no.2
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    • pp.139-151
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    • 2022
  • SAGD (Steam-Assisted Gravity Drainage) method is widely used for oil recovery in oil sands regions. The SAGD operation causes surface displacement, which can affect the stability of oil recovery plants and trigger various geological disasters. Therefore, it isimportant to monitor the surface displacement due to SAGD in the oil sands region. In this study, the surface displacement due to SAGD operations of the Athabasca oil sands region in Alberta, Canada, was observed by applying Permanent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique to the Sentinel-1 time series SAR data acquired from 2016 to 2021. We also investigated the construction and expansion of SAGD facilitiesfrom Landsat-7/8 time seriesimages, from which the characteristics of the surface displacement according to the oil production activity of SAGD were analyzed. Uplift rates of 0.3-2.5 cm/yr in the direction of line of sight were observed over the SAGDs and their vicinity, whereas subsidence rates of -0.3--0.6 cm/yr were observed in areas more than several kilometers away from the SAGDs and not affected by oil recovery activities. Through the analysis of Landsat-7/8 images, we could confirm that the SAGDs operating after 2012 and showing high oil production activity caused uplift rates greater than 1.6 cm/yr due to the subsurface steam injection. Meanwhile, very small uplift rates of several mm per year occurred over SAGDs which have been operated for a longer period of time and show relatively low oil production activity. This was probably due to the compression of reservoir sandstone due to continuous oil recovery. The subsidence observed in areas except for the SAGDs and their vicinity estimated to be a gradual land subsidence caused by melting of the permafrost. Considering the subsidence, it was expected that the uplift due to SAGD operation would be greater than that observed by the PSInSAR. The results of this study confirm that the PSInSAR can be used as an effective means for evaluating productivity and stability of SAGD in the extreme cold regions.

Soil CO2 Monitoring Around Wells Discharging Methane (메탄 유출 관정 주변의 토양 CO2 모니터링)

  • Chae, Gitak;Kim, Chan Yeong;Ju, Gahyeun;Park, Kwon Gyu;Roh, Yul;Lee, Changhyun;Yum, Byoung-Woo;Kim, Gi-Bae
    • Economic and Environmental Geology
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    • v.55 no.4
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    • pp.407-419
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    • 2022
  • Soil(vadose zone) gas compositions were measured for about 3 days to suggest a method for monitoring and interpreting soil gas data collected around wells from which methane(CH4) is outflowing. The vadose zone gas samples were collected within 1 m around two test wells(TB2 and TB3) at Pohang and analyzed for CO2, CH4, N2 and O2 concentrations in situ. CO2 flux was measured beside TB2. In addition, gas samples from well head in TB2 and atmospheric air samples were collected for comparison. Carbon isotopes of CO213CCO2) of samples collected on the last day of the study period were analyzed in the laboratory. The two test wells (TB2 and 3) were 12.7 m apart and only TB3 was cemented to the surface. According to the bio-geochemical process-based interpretation, the relationships between CO2 and O2, N2, and N2/O2 of vadose zone gas were plotted between the lines of CH4 oxidation and CO2 dissolution. In addition, the CH4 concentrations of gas samples from the wellhead of the uncemented well (TB2) were 5.2 times higher than the atmospheric CH4 concentration. High CO2 concentrations (average 1.148%) of vadose zone gas around TB2 seemed to be attributed to the oxidation of CH4. On the other hand, the vadose zone CO2 around the cemented well(TB3) showed a relatively low concentration(0.136%). This difference indicates that the vadose zone gas(including CO2) around the CH4 outflowing well were strongly affected by well completion(cementing). This study result can be used to establish strategies for environmental monitoring of soil around natural gas sites, and can be used to monitor leakage around injection and observation wells for CO2 geological storage. In addition, the method of this study is useful for soil monitoring in natural gas storage and oil-contaminated sites.

A Study on the Expressed Desire at Discharge of Patients to Use Home Nursing and Affecting Factors of the Desire (퇴원환자의 가정간호 이용의사와 관련 요인)

  • Lee, Ji-Hyun;Lee, Young-Eun;Lee, Myung-Hwa;Sohn, Sue-Kyung
    • The Korean Journal of Rehabilitation Nursing
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    • v.2 no.2
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    • pp.257-270
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    • 1999
  • The purpose of this study is to investigate factors related to the intent of using home nursing of chronic disease patients who got out of a university hospital. For the purpose, the study selected 153 patients who were hospitalized and left K university hospital with diagnoses of cancer, hypertension, diabetes and cerebral vascular accident and ordered to be discharged and performed interviews with them and surveys on their medical records to obtain the following results. For this study a direct-interview survey and medical record review was conducted from June 28 to Aug. 30, 1998. The frequency and mean values were computed to find the characteristics of the study subjects, and $X^2$-test, t-test, factor analysis and multiple logistic regession analysis were applied for the analysis of the data. The following results were obtained. 1) When characteristics of the subjects were examined, men and women occupied for 58.8% and 41.2%, respectively. The subjects were 41.3 years old in aver age and had the monthly aver age earning of 0.99 million won or below, which was the most out of the total subjects at 34.6%. Among the total, 87.6% resided in cities and 12.4 in counties. The most left the hospital with diagnosis of cancer at 51.6%, followed by hyper tension at 24.2%, diabetes at 13.7% and cerebral vascular accident at 7.2%. 2) 93.5% of the selected patients had the intent of using home nursing and 6.5%, didn't. Among those patients having the intent, 85.6% had the intent of paying for home nursing and 14.4%, didn't. The subjects expected that the nursing would be paid 9,143 won in aver age and 47.7% of them preferred national authorities as the main servers. 86.3% of the subjects thought that home nursing business had the main advantage of making it possible to learn nursing methods at home and thereby contributing to improving the ability of patients and their facilities to solve health problems. 3) Relations between the intent of use and characteristics of the subjects such as demography-related social, home environment, disease and physical function characteristics did not show statistically significant differences among one another. Compared to those who had no intent of using home nursing, the group having the intent had more cases of male patients, the age of 39 or below, residence in cities, 5 family member s or more, no existence of home nursing servers, leaving the hospital from a non-hospitalized building, disease development for five months or below, hospitalization for ten days or more, non-hospitalization with in the recent one month, two times or over of hospitalization, leaving the hospital with no demand of special treatment, operation underwent, poor results of treatment, leaving the hospital with demand of rehabilitation services, physical disablement and high evaluation point of daily life. 4) Among those patients having the intent of using home nursing, 47.6% demanded technical nursing and 55.9%, supportive nursing. As technical nursing,' inject into a blood vessel ' and 'treat pustule and teach basic prevention methods occupied for 57.4%, respectively, topping the list. Among demands of supportive nursing, 'observe patients 'status and refer them to hospitals or community resources as available, if necessary' was the most with percent age point of 59.5. Regarding the intent of paying for home nursing, 39.2% of those patients wishing to use the nursing responded paying for technical services and 20.2, supportive services. In detail, 70.0% wanted to pay for a service stated as 'inject into a blood vessel', highest among the former services and 30.7%, a service referred to as 'teaching exercises needed to make the body of patients move', highest among the latter. When this was analyzed in terms of a relation between the need(the need for home nursing) and the demand(the intent of paying for home nursing), The rate of the need to the demand was found two or three times higher in technical nursing(0.82) than in supportive nursing(0.35). In aspects of tech ical nursing, muscle injection(1.26, the 1st rank) was highest in the rate while among aspects of supportive nursing, a service referred to as 'teach exercises needed for making patients move their bodies normally'(0.58, the 1st rank). 5) factors I(satisfaction with hospital services), II(recognition of disease state), III(economy) and IV(period of disease) occupied for 34.4, 13.8, 11.9 and 9.2 percents, respectively among factors related to the intent by the subjects of using home nursing, totaled 59.3%. In conclusion, most of chronic disease patients have the intent of using hospital-based home nursing and satisfaction with hospital services is a factor affecting the intent most. Thus a post-management system is needed to continue providing health management to those patients after they leave the hospital. Further, supportive services should be provided in order that those who are satisfied with hospital services return to their community and live their in dependent lives. Based on these results, the researcher would make the following recommendation. 1) Because home nursing becomes more and more needed due to a sharp increase in chronic disease patients and elderly people, related rules and regulations should be made and implemented. 2) Hospital nurses specializing in home nursing should be cultivated.

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Field Studios of In-situ Aerobic Cometabolism of Chlorinated Aliphatic Hydrocarbons

  • Semprini, Lewts
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.3-4
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    • 2004
  • Results will be presented from two field studies that evaluated the in-situ treatment of chlorinated aliphatic hydrocarbons (CAHs) using aerobic cometabolism. In the first study, a cometabolic air sparging (CAS) demonstration was conducted at McClellan Air Force Base (AFB), California, to treat chlorinated aliphatic hydrocarbons (CAHs) in groundwater using propane as the cometabolic substrate. A propane-biostimulated zone was sparged with a propane/air mixture and a control zone was sparged with air alone. Propane-utilizers were effectively stimulated in the saturated zone with repeated intermediate sparging of propane and air. Propane delivery, however, was not uniform, with propane mainly observed in down-gradient observation wells. Trichloroethene (TCE), cis-1, 2-dichloroethene (c-DCE), and dissolved oxygen (DO) concentration levels decreased in proportion with propane usage, with c-DCE decreasing more rapidly than TCE. The more rapid removal of c-DCE indicated biotransformation and not just physical removal by stripping. Propane utilization rates and rates of CAH removal slowed after three to four months of repeated propane additions, which coincided with tile depletion of nitrogen (as nitrate). Ammonia was then added to the propane/air mixture as a nitrogen source. After a six-month period between propane additions, rapid propane-utilization was observed. Nitrate was present due to groundwater flow into the treatment zone and/or by the oxidation of tile previously injected ammonia. In the propane-stimulated zone, c-DCE concentrations decreased below tile detection limit (1 $\mu$g/L), and TCE concentrations ranged from less than 5 $\mu$g/L to 30 $\mu$g/L, representing removals of 90 to 97%. In the air sparged control zone, TCE was removed at only two monitoring locations nearest the sparge-well, to concentrations of 15 $\mu$g/L and 60 $\mu$g/L. The responses indicate that stripping as well as biological treatment were responsible for the removal of contaminants in the biostimulated zone, with biostimulation enhancing removals to lower contaminant levels. As part of that study bacterial population shifts that occurred in the groundwater during CAS and air sparging control were evaluated by length heterogeneity polymerase chain reaction (LH-PCR) fragment analysis. The results showed that an organism(5) that had a fragment size of 385 base pairs (385 bp) was positively correlated with propane removal rates. The 385 bp fragment consisted of up to 83% of the total fragments in the analysis when propane removal rates peaked. A 16S rRNA clone library made from the bacteria sampled in propane sparged groundwater included clones of a TM7 division bacterium that had a 385bp LH-PCR fragment; no other bacterial species with this fragment size were detected. Both propane removal rates and the 385bp LH-PCR fragment decreased as nitrate levels in the groundwater decreased. In the second study the potential for bioaugmentation of a butane culture was evaluated in a series of field tests conducted at the Moffett Field Air Station in California. A butane-utilizing mixed culture that was effective in transforming 1, 1-dichloroethene (1, 1-DCE), 1, 1, 1-trichloroethane (1, 1, 1-TCA), and 1, 1-dichloroethane (1, 1-DCA) was added to the saturated zone at the test site. This mixture of contaminants was evaluated since they are often present as together as the result of 1, 1, 1-TCA contamination and the abiotic and biotic transformation of 1, 1, 1-TCA to 1, 1-DCE and 1, 1-DCA. Model simulations were performed prior to the initiation of the field study. The simulations were performed with a transport code that included processes for in-situ cometabolism, including microbial growth and decay, substrate and oxygen utilization, and the cometabolism of dual contaminants (1, 1-DCE and 1, 1, 1-TCA). Based on the results of detailed kinetic studies with the culture, cometabolic transformation kinetics were incorporated that butane mixed-inhibition on 1, 1-DCE and 1, 1, 1-TCA transformation, and competitive inhibition of 1, 1-DCE and 1, 1, 1-TCA on butane utilization. A transformation capacity term was also included in the model formation that results in cell loss due to contaminant transformation. Parameters for the model simulations were determined independently in kinetic studies with the butane-utilizing culture and through batch microcosm tests with groundwater and aquifer solids from the field test zone with the butane-utilizing culture added. In microcosm tests, the model simulated well the repetitive utilization of butane and cometabolism of 1.1, 1-TCA and 1, 1-DCE, as well as the transformation of 1, 1-DCE as it was repeatedly transformed at increased aqueous concentrations. Model simulations were then performed under the transport conditions of the field test to explore the effects of the bioaugmentation dose and the response of the system to tile biostimulation with alternating pulses of dissolved butane and oxygen in the presence of 1, 1-DCE (50 $\mu$g/L) and 1, 1, 1-TCA (250 $\mu$g/L). A uniform aquifer bioaugmentation dose of 0.5 mg/L of cells resulted in complete utilization of the butane 2-meters downgradient of the injection well within 200-hrs of bioaugmentation and butane addition. 1, 1-DCE was much more rapidly transformed than 1, 1, 1-TCA, and efficient 1, 1, 1-TCA removal occurred only after 1, 1-DCE and butane were decreased in concentration. The simulations demonstrated the strong inhibition of both 1, 1-DCE and butane on 1, 1, 1-TCA transformation, and the more rapid 1, 1-DCE transformation kinetics. Results of tile field demonstration indicated that bioaugmentation was successfully implemented; however it was difficult to maintain effective treatment for long periods of time (50 days or more). The demonstration showed that the bioaugmented experimental leg effectively transformed 1, 1-DCE and 1, 1-DCA, and was somewhat effective in transforming 1, 1, 1-TCA. The indigenous experimental leg treated in the same way as the bioaugmented leg was much less effective in treating the contaminant mixture. The best operating performance was achieved in the bioaugmented leg with about over 90%, 80%, 60 % removal for 1, 1-DCE, 1, 1-DCA, and 1, 1, 1-TCA, respectively. Molecular methods were used to track and enumerate the bioaugmented culture in the test zone. Real Time PCR analysis was used to on enumerate the bioaugmented culture. The results show higher numbers of the bioaugmented microorganisms were present in the treatment zone groundwater when the contaminants were being effective transformed. A decrease in these numbers was associated with a reduction in treatment performance. The results of the field tests indicated that although bioaugmentation can be successfully implemented, competition for the growth substrate (butane) by the indigenous microorganisms likely lead to the decrease in long-term performance.

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The Analysis of Radiation Exposure of Hospital Radiation Workers (병원 방사선 작업 종사자의 방사선 피폭 분석 현황)

  • Jeong Tae Sik;Shin Byung Chul;Moon Chang Woo;Cho Yeong Duk;Lee Yong Hwan;Yum Ha Yong
    • Radiation Oncology Journal
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    • v.18 no.2
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    • pp.157-166
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    • 2000
  • Purpose : This investigation was peformed in order to improve the health care of radiation workers, to predict a risk, to minimize the radiation exposure hazard to them and for them to realize radiation exposure danger when they work in radiation area in hospital. Methods and Materials : The documentations checked regularly for personal radiation exposure in four university hospitals in Pusan city in Korea between January 1, 1993 and December 31, 1997 were analyzed. There were 458 persons in this documented but 111 persons who worked less then one year were excluded and only 347 persons were included in this study. Results : The average of yearly radiation exposure of 347 persons was 1.52$\pm$1.35 mSv. Though it was less than 50mSv, the limitaion of radiation in law but 125 (36%) people received higher radiation exposure than non-radiation workers. Radiation workers under 30 year old have received radiation exposure of mean 1.87$\pm$1.01 mSv/year, mean 1.22$\pm$0.69 mSv between 31 and 40 year old and mean 0.97$\pm$0.43 mSv/year over 41year old (p<0.001). Men received mean 1.67$\pm$1.54 mSv/year were higher than women who received mean 1.13$\pm$0.61 mSv/year (p<0.01). Radiation exposure in the department of nuclear modicine department in spite of low energy sources is higher than other departments that use radiations in hospital (p<0.05). And the workers who received mean 3.59$\pm$1.81 msv/year in parts of management of radiation sources and injection of sources to patient receive high radiation exposure in nuclear medicine department (p<0.01). In department of diagnostic radiology high radiation exposure is in barium enema rooms where workers received mean 3.74$\pm$1.74 mSv/year and other parts where they all use fluoroscopy such as angiography room of mean 1.17$\pm$0.35 mSv/year and upper gastrointestinal room of mean 1.74$\pm$1.34 mSv/year represented higher radiation exposure than average radiation exposure in diagnostic radiology (p<0.01). Doctors and radiation technologists received higher radiation exposure of each mean 1.75$\pm$1.17 mSv/year and mean 1.50$\pm$1.39 mSv/year than other people who work in radiation area in hospital (p<0.05). Especially young doctors and technologists have the high opportunity to receive higher radiation exposure. Conclusions : The training and education of radiation workers for radiation exposure risks are important and it is necessary to rotate worker in short period in high risk area. The hospital management has to concern health of radiation workers more and to put an effort to reduce radiation exposure as low as possible in radiation areas in hospital.

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