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Study on accuracy of panorama and CBCT through length measurement of wisdom teeth (사랑니 길이 측정을 통한 파노라마와 CBCT의 정확도 연구)

  • Jeong, Cheonsoo;Kim, Chongyeal
    • Journal of the Korean Society of Radiology
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    • v.7 no.2
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    • pp.131-136
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    • 2013
  • Panorama of dental radiation generators can observe the wide anatomical structures of oral and maxillofacial areas but there can be distortion of lengths, angles, or shapes. CBCT can diagnose 3D images and get the ones whose errors by superposition and interference are remarkably smaller between anatomical structures. But the quality of the images by movement of subjects can be lowered as it takes long to diagnose them. And if there are impermeable radiation objects like metal in mouths, impermeable radiation lines can radially appear with the objects as center. This study tries to analyze accuracy of panorama and CBCT and get useful anatomical information in dental treatment by comparing the length of wisdom teeth which were measured by Panorama and CBCT with the teeth which were actually extracted and analyzing distortion of the teeth. The test result could be found that Panorama is expanded by average 7.3% as the errors of Panorama and Digital Vernier Caliper range from 110.7% to 103.9%. The length of wisdom teeth which were measured in CBCT and Digital Vernier Caliper could be found that the error range is 1.3%. And the length of wisdom teeth which were measured in Panorama and Digital Vernier Caliper has found that the error range shows 7.3%. So it could be found that the images of CBCT is about 6% more exact than those of Panorama. It could be found that CBCT shows the more exact images than those of Panorama. But because the examination expenses of CBCT are higher than those of Panorama and exposure dose of CBCT is much more than that of Panorama, it is thought to find proper ways in examination.

Study on Soil Extraction Methods for the Human Health Risk Assessment of Crop Intake Pathway around Abandoned Metal Mine Areas (폐금속광산 지역 농작물섭취경로의 인체위해도 산정을 위한 생물농축계수와 토양분석방법에 관한 연구)

  • Lim, Tae-Yong;Lee, Sang-Woo;Yun, Seong-Taek;Kim, Soon-Oh
    • Journal of Soil and Groundwater Environment
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    • v.21 no.6
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    • pp.56-66
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    • 2016
  • Generally, the contribution of crop-intake pathway (CIP) is remarkable in human health assessment (HHA) of heavy metal contamination. Although the crop exposure concentrations (Cp) should directly be used for calculating the average daily dose (ADD) of CIP, the soil exposure concentration (Cs) multiplied by soil-crop bio-concentration factor (BCF) has frequently been used instead of using Cp values. Thus, the BCF values are significant in the HHA, and care should be taken to ensure the reasonable acquisition of BCF values. Meanwhile, the BCF values are known to be significantly affected by analytical methods. Nevertheless, they have been calculated from the concentrations of soil and crop analyzed by only one method: total digestion (aqua regia extraction). For this reason, this study was initiated to seek appropriate soil analysis methods for effective computation of the ADD of CIP. The concentrations of 5 metal contaminants (As, Cd, Cu, Pb, and Zn) in 127 soil samples obtained from 4 abandoned metal mine areas were analyzed by several methods including total digestion and partial digestions using 0.1/1 N HCl, 1M $NH_4NO_3$, 0.1 M $NaNO_3$, and 0.01M $CaCl_2$. The heavy metal concentrations in 127 crop samples (rice grains) were analyzed by total digestion as well. Using the concentrations of soils and crops, the BCF values of each contaminant were calculated according to the kind of soil extraction methods applied. Finally, the errors between Cp and $C_s{\times}BCF$ were computed to evaluate the relevance of each method. The results indicate that the partial extraction using 0.1 N and 1 N HCl was superior or equivalent to total digestion. In addition, the 0.1M $NaNO_3$ method combined with total digestion is recommended for improving the reliability of BCF values.

Studies On Intestinal Trematodes in Korea XIII. Two Cases of Human Infection by Heterophyopsis continua and the Status of Metacercarial Infection in Brackish Water Fishes (한국의 간흡충에 관한 연구 XIII. Heterophyopsis continua에 의한 인체감염 2례)

  • 서병설;이순형
    • Parasites, Hosts and Diseases
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    • v.22 no.1
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    • pp.51-60
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    • 1984
  • Two cases of natural human infection by Heterophyopsis continua (Heterophyidae) were identified by collection of adult worms in 1983 in Korea. And in order to know the source of infection a study on fish intermediate hosts was performed along the southwestern coastal areas. The cases were 21 and 50 year old males residing in southern coastal areas. They had the clinical complaints of non-specific gastrointestinal symptoms such as epigastric pain and one of them also complained the discharge of tapeworm segments. Praziquantel in single dose of 10~15mg/kg was given followed by purgation with magnesium salt and 2 and 46 specimens of H. continua were collected from the diarrheal stools. They said to have eaten raw ilesh of several kinds of brackish water fishes. The results of fish examination for metacercarial infection were as follows: I. Seventeen (663.0%) out of 27 perches (Lateolabrax japonicus) and 10 (29.4%) out of 34 gobies (Acantkogobius flavimanus) harboured the metacercariae but none of 42 mullets (Mugil cepkalus) were found to harbour them. 2. The average metacercarial density in perches was 55.1 and 18.7 per fish respectively. And the majority of the metacercariae were collected from the muscle of body portions in these fishes. 3. After the metaeercariae were experimentally fed to two rats and one young dog. two adult worms were recovered from the dog while none from the rats. These worms were also identified as H. continua. From the results it was concluded that the brackish water flshes which the human cases said to have eaten were the source of infection.

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The Use of Iron Supplements of Pregnant Women and Pregnancy Outcome (임신부의 철분 보충제 사용과 임신결과)

  • Cho, Ji-Hyun;Ahn, Hong-Seok;Bae, Hyun-Sook
    • Korean Journal of Community Nutrition
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    • v.14 no.3
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    • pp.327-339
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    • 2009
  • It is known that Korean pregnant women take iron supplements at a higher than the recommended level. This study was designed to provide data on current iron intake levels both from food sources and supplement to better guide iron supplement use during pregnancy. We also explored associations of iron supplement intake levels with various sociocultural factors and pregnancy outcomes. Dietary intakes of 510 pregnant women were assessed by a validated 102-item food frequency questionnaire, and information on types and amounts of nutritional supplement intakes were also attained. While dietary intake levels of most nutrients exceeded the KDRIs (Korea Dietary Reference Intakes: EAR: Estimated Average Requirements), folate fell short of the KDRIs. A total of 428 women (83.9%) reported to take iron supplement. The pregnant women were divided into the three groups (group I: Fe supplement intake ${\le}$ EAR, group II: EAR < Fe supplement intake ${\le}$ 3 times of EAR, group III: 3 times of EAR < Fe supplement intake). The mean dietary intake of iron was 24% of the total iron intake for pregnant women. Iron intake from food was not significantly different among I, II, and III. In case of iron intake from supplements, the most frequent dose (34.1%) was 90-100 mg/day, and the mean iron supplement intake was 362% of the EAR. The study findings showed that those with higher levels of iron supplements had better meal quality measured by NAR (Nutrient Adequacy Ratio) and INQ (Index of Nutrient Quality). In addition iron supplement intake levels were significantly related to age (20s: 66.5 ${\pm}$ 38.6 mg/day, 30s: 77.3 ${\pm}$ 47.8 mg/day, p < 0.0116) and experience of childbirth (1st pregnancy: 70.9 ${\pm}$ 41.2 mg/day, 2nd pregnancy: 64.5 ${\pm}$ 39.5 mg/day, ${\ge}$ 3rd pregnancy: 94.4 ${\pm}$ 63.8 mg/day, p < 0.005). However, no significant difference was found between iron supplement intake levels and various pregnancy outcomes including birth weight, birth height, gestational age, weight gain during pregnancy, and jaundice. It is worrisome that iron intake by supplement use greatly exceeded the EAR, suggesting the need of appropriate guidelines for iron supplement intake during pregnancy. Thus iron overdose from supplements in pregnancy should be considered as a serious condition.

Study on Mercury Contamination in Multimedia Environment in Lake So-Yang (소양호 다중매체 내 수은오염실태 조사)

  • Park, Sang-Young;Yoo, Seong;Shin, Hyung-Cheol;Kim, Seong-Rak;Kim, Pyung-Rae;Ahn, Myung-Chan;Han, Young-Ji
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.3
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    • pp.202-211
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    • 2011
  • In this study the seasonal and spatial pattern of mercury (Hg) concentrations in multimedia environments were investigated in Lake So-Yang. Total mercury (TM) in water column greatly enhanced as turbidity and particulate organic carbon (POC) increased due to the severe runoff, suggesting that most of Hg existed as particulate Hg in Lake Soyang. We also collected 22 species of fish in Lake Soyang and Han River, and the average total mercury in fish was 0.073 ppm, lower than both Korean (0.5 ppm) and EPA criteria (0.3 ppm). However when considering the amount of fish intake for Korean the Hg criterion in fish must be more stringent than current value, and the advisory for fish consumption should be made. Hg in fish considerably varied with sampling sites, having the highest in the upper region (Yang-gu) and the lowest in downstream (Han River). This spatial variation was possibly derived by "bloom dilution" associated with high phosphorus loading or elevated DOC concentrations, or both. Total mercury in sediment varied from 69.9 to $98.3{\mu}g/kg$, which was relatively lower than those measured in Voyageurs National Park in Minnesota in USA ($102{\sim}364{\mu}g/kg$).

Evaluation and Experimental Production of Single-Phase Full-wave Rectification Type for X-ray Equipment of High Precision (고정밀도의 단상전파정류형 X선 장치의 제작 및 평가)

  • Han, Dong-Kyoon;Jung, Jae-Eun;Choi, Jun-Gu;Seoun, Youl-Hun;Ko, Shin-Gwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.1
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    • pp.413-419
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    • 2011
  • Diagnosis X-ray equipment localized at 1950's but it is developed suddenly at 1960's with demand together. Manufacture of Diagnostic X-ray equipment is controled by the KS regulation and the Ministry of Health and Welfare because of hazardous element etc. exposure by radiation. Most of diagnostic X-ray equipment ware single phase and three phase full-wave rectification but from 1980's it transforms it was exchanged in inverter type X-ray equipment. Inverter type X-ray equipment produces approximately 50~80% more average photon intensity then single phase full-wave rectification and the accuracy is high. But from a clinic it dose not use because expensive therefor the efficiency improvement of single phase full-wave rectification is necessary. We produced single phase full-wave rectification X-ray equipment control unit, high tension transformer, filament heating transformer, rectification circuit, high tension cable and others and evaluated efficiency, in result which is excellent compare with Rule of Safety Management and KS regulation.

Comparative nitrogen use efficiency of urea and pig slurry for regrowth yield and nutritive value in perennial ryegrass sward

  • Park, Sang Hyun;Lee, Bok Rye;Cho, Won Mo;Kim, Tae Hwan
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.4
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    • pp.514-522
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    • 2017
  • Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

Nutrient intake, digestibility and performance of Gaddi kids supplemented with tea seed or tea seed saponin extract

  • Kumar, M.;Kannan, A.;Bhar, R.;Gulati, A.;Gaurav, A.;Sharma, V.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.4
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    • pp.486-494
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    • 2017
  • Objective: An experiment was conducted to determine the nutrient intake, digestibility, microbial protein synthesis, haemato-biochemical attributes, immune response and growth performance of Gaddi kids fed with oat fodder based basal diet supplemented with either tea seed or tea seed saponin (TSS) extract. Methods: Eighteen male kids, $7.03{\pm}0.16$ months of age and $19.72{\pm}0.64kg$ body weight, were distributed into three groups, $T_0$ (control), $T_1$, and $T_2$, consisting of 6 animals each in a completely randomized design. The kids were fed a basal diet consisting of concentrate mixture and oat fodder (50:50). Animals in group III ($T_2$) were supplemented with TSS at 0.4% of dry matter intake (DMI), and group II ($T_1$) were supplemented with tea seed at 2.6% of DMI to provide equivalent dose of TSS as in $T_2$. Two metabolism trials were conducted, 1st after 21 days and 2nd after 90 days of feeding to evaluate the short term and long term effects of supplementation. Results: The tea seed ($T_1$) or TSS ($T_2$) supplementation did not affect DMI as well as the digestibility of dry matter, organic matter, crude protein, neutral detergent fibre, and acid detergent fibre. Nutritive value of diet and plane of nutrition were also comparable for both the periods. However, the average daily gain and feed conversion ratio (FCR) were improved (p<0.05) for $T_1$ and $T_2$ as compared to $T_0$. The microbial protein supply was also higher (p<0.05) for $T_1$ and $T_2$ for both the periods. There was no effect of supplementation on most blood parameters. However, the triglyceride and low density lipoprotein cholesterol levels decreased (p<0.05) and high density lipoprotein-cholesterol level increased (p<0.05) in $T_2$ as compared with $T_0$ and $T_1$. Supplementation also did not affect the cell mediated and humoral immune response in goats. Conclusion: Tea seed at 2.6% of DMI and TSS at 0.4% DMI can be fed to Gaddi goats to improve growth rate, FCR and microbial protein synthesis.

Environmental Radioactivity and High Incidence Rates of Stomach and Esophagus Cancer in the Van Lake Region: A Causal Relationship?

  • Akan, Zafer;Baskurt, Busranur;Asliyuksek, Hizir;Kam, Erol;Yilmaz, Ahmet;Yuksel, Mehmet Bilgehan;Biyik, Recep;Esen, Ramazan;Koca, Dogan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.375-380
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    • 2014
  • This study examined the incidence rates of cancer cases (averages for 2006-2010) and relationships with environmental radioactivity levels. Soil and water samples were collected from provincial and district centers of Van city and the outdoor gamma doses were determined using a portable gamma scintillation detector. Gross alpha and beta, (226)Ra, (232)Th, and (40)K activities were measured in both tap water and soil samples. Although high rates of stomach and esophagus cancers have been reported previously in Van the underlying reasons have not hitherto been defined. Incidences of cancers were highest in the Gurpmar (326.0) and Ozalp (377.1) counties (p<0.001). As to the results of the gross alpha and gross beta radioactivity measurements in the drinking water, these two counties also had high beta radionuclide levels: Gurpmar ($140mBq/dm^3$) and Ozalp ($206mBq/dm^3$). Even if within the normal range, a relation between the higher rate of the incidence of stomach and esophagus cancers with that of the higher rate of beta radionuclide activity was clear. On Spearman correlation analysis, the relation between higher beta radionuclide levels and cancer incidence was found to be statistically significant (p<0.01). According to the results of the analysis, Van residents receive an average 1.86 mSv/y annual dose from outdoor gamma radiation, ingestion of radionuclides in the drinking water, and indoor $^{222}Rn$ activity. Moreover, gross alpha and beta activities were found to be extremely high in all of the lakes around the city of Van, Turkey. Further investigations with long-term detailed environmental radiation measurements are needed regarding the relationship between cancer cases and environmental radioactivity in the city of Van.

Assessment of health risk associated with arsenic exposure from soil, groundwater, polished rice for setting target cleanup level nearby abandoned mines

  • Lee, Ji-Ho;Kim, Won-Il;Jeong, Eun-Jung;Yoo, Ji-Hyock;Kim, Ji-Young;Lee, Je-Bong;Im, Geon-Jae;Hong, Moo-Ki
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.1
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    • pp.38-47
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    • 2011
  • This study focused on health risk assessment via multi-routes of As exposure to establish a target cleanup level (TCL) in abandoned mines. Soil, ground water, and rice samples were collected near ten abandoned mines in November 2009. The As contaminations measured in all samples were used for determining the probabilistic health risk by Monte-Carlo simulation techniques. The human exposure to As compound was attributed to ground water ingestion. Cancer risk probability (R) via ground water and rice intake exceeded the acceptable risk range of $10^{-6}{\sim}10^{-4}$ in all selected mines. In particular, the MB mine showed the higher R value than other mines. The non-carcinogenic effects, estimated by comparing the average As exposure with corresponding reference dose were determined by hazard quotient (HQ) values, which were less than 1.0 via ground water and rice intake in SD, NS, and MB mines. This implied that the non-carcinogenic toxic effects, due to this exposure pathway had a greater possibility to occur than those in other mines. Besides, hazard index (HI) values, representing overall toxic effects by summed the HQ values were also greater than 1.0 in SD, NS, JA, and IA mines. This revealed that non-carcinogenic toxic effects were generally occurred. The As contaminants in all selected mines exceeded the TCL values for target cancer risk ($10^{-6}$) through ground water ingestion and rice intake. However, the As level in soil was greater than TCL value for target cancer risk via inadvertent soil ingestion pathway, except for KK mine. In TCL values for target hazard quotient (THQ), the As contaminants in soil did not exceed such TCL value. On the contrary, the As levels in ground water and polished rice in SD, NS, IA, and MB mines were also beyond the TCL values via ground water and rice intake. This study concluded that the health risks through ground water and rice intake were greater than those though soil inadvertent ingestion and dermal contact. In addition, it suggests that the abandoned mines to exceed the risk-based TCL values are carefully necessary to monitor for soil remediation.