• Title/Summary/Keyword: Cr

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Propagation Characteristics of Diabelia spathulata Siebold & Zucc. Population, a Rare plant in Korea (희귀식물 주걱댕강나무 개체군의 번식 특성)

  • Jeong Gul Jang;Sung-Tae Yu;Byung-Do Kim;Myung-Hoon Yi;Hye-Yeon Kwon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2021.04a
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    • pp.21-21
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    • 2021
  • 주걱댕강나무는 경남 양산의 천성산에서만 생육하는 산림청·국립수목원 지정 희귀식물(Critically Endangered, CR)로 현지외 보전 및 대체 서식지 조성을 위해 번식 특성에 대해 알아보았다. 종자번식의 경우 450립의 종자를 저장방법에 따라 파종한 결과 노천매장 3.56%, 저온건조저장 0.67%, 습사저온저장 0.22%로 발아율이 매우 저조하였으며, 배양토 조건에 따라 직파 실험한 결과 모래 2.44%, 원예용 상토 2.22%, 현지내 산림토 1.11%, 현지외 산림토 0%로 이 또한 발아율이 매우 저조하였다. 삽목번식의 경우 숙지삽은 모래+펄라이트 36.1%, 모래 31.1%, 원예용 상토 20.0%로 나타났으며, 휴면지 삽수의 발근촉진제 처리 효과는 IBA 1,000PPM에서 37.8%, IBA 7,000PPM 30.0%, 무처리 28.9%, IBA 5,000PPM 27.8%의 발근율을 보였고 신초길이, 뿌리의 수, 뿌리 길이는 전반적으로 발근촉진제 처리와 함께 농도가 높아질수록 뿌리 성장이 왕성한 것으로 나타났다. 녹지삽은 모래 80%, 모래+펄라이트 76.7%, 피트모스+마사토 73.3%, 피트모스+펄라이트+버미큘라이트 70.0% 순이며, 왕모래와 왕모래+마사토는 26.7%와 36.7%로 다소 저조하였다. 녹지삽수의 굵기는 4mm이상 구간에서 발근율이 73.3%로 가장 높았으며, 녹지삽수의 길이는 7~8cm 구간에서 80.0%로 가장 높게 나타나 삽수의 굵기가 굵고 8cm내외의 길이가 효율적인 것으로 나타났다. 근삽은 발아율이 88.3~96.7%로 모든 배양토에서 높게 나타났다. 근삽수 직경 7~8mm에서 100%이며 3~4mm 또한 91%로 나타났다. 근삽수 길이는 4~5cm와 10~11cm에서 100%, 6~7cm 88.1%, 8~9cm 94.4%로 나타나 4~5cm를 제외하고는 삽수 길이가 길수록 신초 생장과 발근이 비례하는 것을 확인하였다. 주걱댕강나무는 실생보다 삽목번식이 더 효율적이며, 그 중 근삽이 가장 발근율이 높다. 배양토는 모래 단용구를 제외하고는 평균 95%이상으로 나타났으며, 근삽수는 직경이 굵고 길수록 신초 생장과 발근이 왕성하다. 따라서, 현지외 보전을 위해 향후 휴면성의 종자 발아 연구가 필요하며, 영양번식을 할 경우 근삽이 가장 효율적인 것을 확인하였다.

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Estimation of Bridge Vehicle Loading using CCTV images and Deep Learning (CCTV 영상과 딥러닝을 이용한 교량통행 차량하중 추정)

  • Suk-Kyoung Bae;Wooyoung Jeong;Soohyun Choi;Byunghyun Kim;Soojin Cho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.28 no.3
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    • pp.10-18
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    • 2024
  • Vehicle loading is one of the main causes of bridge deterioration. Although WiM (Weigh in Motion) can be used to measure vehicle loading on a bridge, it has disadvantage of high installation and maintenance cost due to its contactness. In this study, a non-contact method is proposed to estimate the vehicle loading history of bridges using deep learning and CCTV images. The proposed method recognizes the vehicle type using an object detection deep learning model and estimates the vehicle loading based on the load-based vehicle type classification table developed using the weights of empty vehicles of major domestic vehicle models. Faster R-CNN, an object detection deep learning model, was trained using vehicle images classified by the classification table. The performance of the model is verified using images of CCTVs on actual bridges. Finally, the vehicle loading history of an actual bridge was obtained for a specific time by continuously estimating the vehicle loadings on the bridge using the proposed method.

Deep Learning-Based Algorithm for the Detection and Characterization of MRI Safety of Cardiac Implantable Electronic Devices on Chest Radiographs

  • Ue-Hwan Kim;Moon Young Kim;Eun-Ah Park;Whal Lee;Woo-Hyun Lim;Hack-Lyoung Kim;Sohee Oh;Kwang Nam Jin
    • Korean Journal of Radiology
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    • v.22 no.11
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    • pp.1918-1928
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    • 2021
  • Objective: With the recent development of various MRI-conditional cardiac implantable electronic devices (CIEDs), the accurate identification and characterization of CIEDs have become critical when performing MRI in patients with CIEDs. We aimed to develop and evaluate a deep learning-based algorithm (DLA) that performs the detection and characterization of parameters, including MRI safety, of CIEDs on chest radiograph (CR) in a single step and compare its performance with other related algorithms that were recently developed. Materials and Methods: We developed a DLA (X-ray CIED identification [XCID]) using 9912 CRs of 958 patients with 968 CIEDs comprising 26 model groups from 4 manufacturers obtained between 2014 and 2019 from one hospital. The performance of XCID was tested with an external dataset consisting of 2122 CRs obtained from a different hospital and compared with the performance of two other related algorithms recently reported, including PacemakerID (PID) and Pacemaker identification with neural networks (PPMnn). Results: The overall accuracies of XCID for the manufacturer classification, model group identification, and MRI safety characterization using the internal test dataset were 99.7% (992/995), 97.2% (967/995), and 98.9% (984/995), respectively. These were 95.8% (2033/2122), 85.4% (1813/2122), and 92.2% (1956/2122), respectively, with the external test dataset. In the comparative study, the accuracy for the manufacturer classification was 95.0% (152/160) for XCID and 91.3% for PPMnn (146/160), which was significantly higher than that for PID (80.0%,128/160; p < 0.001 for both). XCID demonstrated a higher accuracy (88.1%; 141/160) than PPMnn (80.0%; 128/160) in identifying model groups (p < 0.001). Conclusion: The remarkable and consistent performance of XCID suggests its applicability for detection, manufacturer and model identification, as well as MRI safety characterization of CIED on CRs. Further studies are warranted to guarantee the safe use of XCID in clinical practice.

Examination of Soil Contamination Status and Improvement Strategies within Urban Development Projects (도시개발사업 내 토양 오염 현황과 개선 방안 고찰)

  • Heo, Sujung;Lee, Dong-Kun;Kim, Eunsub;Jeon, Seong-Woo;Jin, Zhiying
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.27 no.3
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    • pp.45-56
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    • 2024
  • Heavy metals emitted from urban development do not decompose in the soil and remain for long periods, continually impacting the environment. Since the mid-1990s, there has been increasing societal concern in South Korea regarding soil contamination, prompting various legislative revisions to reduce pollution. This study utilizes the Environmental Impact Assessment Support System (EIASS) to investigate projects in the metropolitan area that have exceeded the Ministry of Environment's soil contamination concern levels from 1989 to 2022 and to examine improvements in the environmental impact assessment (EIA) process. The results reveal that the average concentrations of nine contaminants-cadmium (Cd), copper (Cu), arsenic (As), mercury (Hg), lead (Pb), hexavalent chromium (Cr6+), zinc (Zn), nickel (Ni), and fluoride (F)-have all increased over the years. Among these, Zn had the highest relative proportion, with 37.5% of the 40 sites exceeding environmental concern levels. Investigation of 19 specific projects at these exceedance sites showed that only 7 had documented analyses of contamination causes and remediation plans, and just one had contracted additional remediation services, though results from these efforts were found to be lacking. Furthermore, since 2019, a significant proportion of these sites were involved in residential developments, likely due to government initiatives in new city development and extensive housing supply plans. This research emphasizes the importance of public disclosure of the processes and outcomes of remediation efforts on historically contaminated soils prior to project development. It discusses improvements to the EIA by reviewing current legislation and international examples. The findings of this study are expected to heighten public awareness about heavy metal contamination and enhance transparency in soil remediation efforts, contributing to sustainable environmental management and development.

Analytic Hierarchy Process approach to estimate weights of menu management in the school foodservice (계층적 분석과정을 적용한 학교급식 식단 구성의 중요도 분석)

  • Hyo Bin Im;Seo Ha Lee;Hojin Lee;Lana Chung;Min A Lee
    • Journal of Nutrition and Health
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    • v.57 no.3
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    • pp.349-364
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    • 2024
  • Purpose: This study used the Analytic Hierarchy Process to evaluate the relative importance of the factors that school nutrition teachers and dietitians consider during menu planning for school foodservices across various educational levels. Methods: An online survey was conducted from December 2023 to January 2024. The hierarchical structure for school foodservice menu management was developed through content analysis, consisting of five high-level categories and 3-4 low-level factors. Questionnaires were distributed to 395 nutrition teachers and dietitians from kindergarten, elementary, middle, and high schools nationwide. One hundred and sixty-six responses were received, resulting in a 42.0% return rate. These responses were analyzed using Microsoft Excel and SPSS Statistics. Results: The most commonly referenced sources for school foodservice menu planning were 'menus obtained from websites' (19.4%). The most significant challenge encountered was 'incorporating students' preferences' (18.6%). In the hierarchy of categories considered for school foodservice menu management, 'employees and facilities' ranked highest (0.2347), followed by 'preference' (0.2312), 'nutrition balance' (0.2027), 'cooking process' (0.1726), and 'food materials' (0.1588). Within each category, the top-ranked factors were 'employees' cooking skills' (0.3759), 'students' preferences' (0.4310), 'dietary reference intakes' (0.4968), 'foodservice hygiene' (0.4374), and 'food costs' (0.4213). The study also compared the relative importance of factors according to the educational levels, and the top-ranked factors were the same across all educational levels. In particular, 'students' preferences', 'dietary reference intake', and 'food costs' aligned with the top three challenges in school foodservice menu planning. Conclusion: Enhancing working conditions for school foodservice employees and developing menu planning methods that accommodate students' preferences are necessary. These findings will provide foundational data for future school foodservice menu management strategies.

Specific Alternation of Gut Microbiota and the Role of Ruminococcus gnavus in the Development of Diabetic Nephropathy

  • Jinni Hong;Tingting Fu;Weizhen Liu;Yu Du;Junmin Bu;Guojian Wei;Miao Yu;Yanshan Lin;Cunyun Min;Datao Lin
    • Journal of Microbiology and Biotechnology
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    • v.34 no.3
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    • pp.547-561
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    • 2024
  • In this study, we aim to investigate the precise alterations in the gut microbiota during the onset and advancement of diabetic nephropathy (DN) and examine the impact of Ruminococcus gnavus (R. gnavus) on DN. Eight-week-old male KK-Ay mice were administered antibiotic cocktails for a duration of two weeks, followed by oral administration of R. gnavus for an additional eight weeks. Our study revealed significant changes in the gut microbiota during both the initiation and progression of DN. Specifically, we observed a notable increase in the abundance of Clostridia at the class level, higher levels of Lachnospirales and Oscillospirales at the order level, and a marked decrease in Clostridia_UCG-014 in DN group. Additionally, there was a significant increase in the abundance of Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae at the family level. Moreover, oral administration of R. gnavus effectively aggravated kidney pathology in DN mice, accompanied by elevated levels of urea nitrogen (UN), creatinine (Cr), and urine protein. Furthermore, R. gnavus administration resulted in down-regulation of tight junction proteins such as Claudin-1, Occludin, and ZO-1, as well as increased levels of uremic toxins in urine and serum samples. Additionally, our study demonstrated that orally administered R. gnavus up-regulated the expression of inflammatory factors, including nucleotide-binding oligomerization domain-like receptor pyrin domain-containing protein 3 (NLRP3) and Interleukin (IL)-6. These changes indicated the involvement of the gut-kidney axis in DN, and R. gnavus may worsen diabetic nephropathy by affecting uremic toxin levels and promoting inflammation in DN.

Analysis of the Efficiency of Entrepreneurship Support in Korean Universities (국내 대학의 창업지원 효율성 분석)

  • Heung-Hee Kim;Dae-Geun Kim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.19 no.4
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    • pp.87-101
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    • 2024
  • This study aims to provide insights for the efficient utilization of resources by analyzing the entrepreneurship support efficiency of Korean universities. To identify the factors influencing the number of entrepreneurs, which is the primary goal of university entrepreneurship support, a multiple regression analysis was conducted, identifying five effective independent variables. Using these five identified independent variables as input variables and the number of entrepreneurs as the output variable, the DEA method was used to analyze the efficiency of entrepreneurship support for each university as of 2023. The analysis of 150 four-year universities in Korea showed that nine universities exhibited complete efficiency in both CCR and BCC models. Among the remaining 141 universities that showed inefficiency, the cause was scale for five universities, technology for two universities, and both scale and technology for 134 universities. Regarding the returns to scale, nine universities exhibited CRS, 79 exhibited IRS, and 62 exhibited DRS. Additionally, reference groups that could serve as benchmarks for improving the efficiency of inefficient universities were identified, and target values(projections) for each variable to achieve efficiency were also presented. Despite the limitations of the DEA model, this study helps each university identify the causes of inefficiency in their entrepreneurship support and derive specific improvements to enhance efficiency. This facilitates more efficient resource management and can positively impact the ultimate goals of university entrepreneurship support, such as regional economic development and job creation.

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Consumer Responses to Retailer's Location-based Mobile Shopping Service : Focusing on PAD Emotional State Model and Information Relevance (유통업체의 위치기반 모바일 쇼핑서비스 제공에 대한 소비자 반응 : PAD 감정모델과 정보의 상황관련성을 중심으로)

  • Lee, Hyun-Hwa;Moon, Hee-Kang
    • Journal of Distribution Research
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    • v.17 no.2
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    • pp.63-92
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    • 2012
  • This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective responses. Information relevancy was integrated into pleasure-arousal-dominance (PAD) emotional state model in the present study as a conceptual framework. The results of an online survey of 335 mobile phone users in the U.S. indicated the positive effects of arousal and information relevancy on pleasure. In addition, there was a significant relationship between pleasure and intention to use a LBMSS. However, the relationship between dominance and pleasure was not statistically significant. The results of the present study provides insight to retailers and marketers as to what factors they need to consider to implement location-based mobile shopping services to improve their business performance. Extended Abstract : Location aware technology has expanded the marketer's reach by reducing space and time between a consumer's receipt of advertising and purchase, offering real-time information and coupons to consumers in purchasing situations (Dickenger and Kleijnen, 2008; Malhotra and Malhotra, 2009). LBMSS increases the relevancy of SMS marketing by linking advertisements to a user's location (Bamba and Barnes, 2007; Malhotra and Malhotra, 2009). This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective response. The purpose of the study was to examine the relationship among information relevancy and affective variables and their effects on intention to use LBMSS. Thus, information relevancy was integrated into pleasure-arousal-dominance (PAD) model and generated the following hypotheses. Hypothesis 1. There will be a positive influence of arousal concerning LBMSS on pleasure in regard to LBMSS. Hypothesis 2. There will be a positive influence of dominance in LBMSS on pleasure in regard to LBMSS. Hypothesis 3. There will be a positive influence of information relevancy on pleasure in regard to LBMSS. Hypothesis 4. There will be a positive influence of pleasure about LBMSS on intention to use LBMSS. E-mail invitations were sent out to a randomly selected sample of three thousand consumers who are older than 18 years old and mobile phone owners, acquired from an independent marketing research company. An online survey technique was employed utilizing Dillman's (2000) online survey method and follow-ups. A total of 335 valid responses were used for the data analysis in the present study. Before the respondents answer any of the questions, they were told to read a document describing LBMSS. The document included definitions and examples of LBMSS provided by various service providers. After that, they were exposed to a scenario describing the participant as taking a saturday shopping trip to a mall and then receiving a short message from the mall. The short message included new product information and coupons for same day use at participating stores. They then completed a questionnaire containing various questions. To assess arousal, dominance, and pleasure, we adapted and modified scales used in the previous studies in the context of location-based mobile shopping service, each of the five items from Mehrabian and Russell (1974). A total of 15 items were measured on a seven-point bipolar scale. To measure information relevancy, four items were borrowed from Mason et al. (1995). Intention to use LBMSS was captured using two items developed by Blackwell, and Miniard (1995) and one items developed by the authors. Data analyses were conducted using SPSS 19.0 and LISREL 8.72. A total of usable 335 data were obtained after deleting the incomplete responses, which results in a response rate of 11.20%. A little over half of the respondents were male (53.9%) and approximately 60% of respondents were married (57.4%). The mean age of the sample was 29.44 years with a range from 19 to 60 years. In terms of the ethnicity there were European Americans (54.5%), Hispanic American (5.3%), African-American (3.6%), and Asian American (2.9%), respectively. The respondents were highly educated; close to 62.5% of participants in the study reported holding a college degree or its equivalent and 14.5% of the participants had graduate degree. The sample represents all income categories: less than $24,999 (10.8%), $25,000-$49,999 (28.34%), $50,000-$74,999 (13.8%), and $75,000 or more (10.23%). The respondents of the study indicated that they were employed in many occupations. Responses came from all 42 states in the U.S. To identify the dimensions of research constructs, Exploratory Factor Analysis (EFA) using a varimax rotation was conducted. As indicated in table 1, these dimensions: arousal, dominance, relevancy, pleasure, and intention to use, suggested by the EFA, explained 82.29% of the total variance with factor loadings ranged from .74 to .89. As a next step, CFA was conducted to validate the dimensions that were identified from the exploratory factor analysis and to further refine the scale. Table 1 exhibits the results of measurement model analysis and revealed a chi-square of 202.13 with degree-of-freedom of 89 (p =.002), GFI of .93, AGFI = .89, CFI of .99, NFI of .98, which indicates of the evidence of a good model fit to the data (Bagozzi and Yi, 1998; Hair et al., 1998). As table 1 shows, reliability was estimated with Cronbach's alpha and composite reliability (CR) for all multi-item scales. All the values met evidence of satisfactory reliability in multi-item measure for alpha (>.91) and CR (>.80). In addition, we tested the convergent validity of the measure using average variance extracted (AVE) by following recommendations from Fornell and Larcker (1981). The AVE values for the model constructs ranged from .74 through .85, which are higher than the threshold suggested by Fornell and Larcker (1981). To examine discriminant validity of the measure, we again followed the recommendations from Fornell and Larcker (1981). The shared variances between constructs were smaller than the AVE of the research constructs and confirm discriminant validity of the measure. The causal model testing was conducted using LISREL 8.72 with a maximum-likelihood estimation method. Table 2 shows the results of the hypotheses testing. The results for the conceptual model revealed good overall fit for the proposed model. Chi-square was 342.00 (df = 92, p =.000), NFI was .97, NNFI was .97, GFI was .89, AGFI was .83, and RMSEA was .08. All paths in the proposed model received significant statistical support except H2. The paths from arousal to pleasure (H1: ${\ss}$=.70; t = 11.44), from information relevancy to intention to use (H3 ${\ss}$ =.12; t = 2.36), from information relevancy to pleasure (H4 ${\ss}$ =.15; t = 2.86), and pleasure to intention to use (H5: ${\ss}$=.54; t = 9.05) were significant. However, the path from dominance to pleasure was not supported. This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective responses. Information relevancy was integrated into pleasure-arousal-dominance (PAD) emotional state model as a conceptual framework. The results of the present study support previous studies indicating that emotional responses as well as cognitive responses have a strong impact on accepting new technology. The findings of this study suggest potential marketing strategies to mobile service developers and retailers who are considering the implementation of LBMSS. It would be rewarding to develop location-based mobile services that integrate information relevancy and which cause positive emotional responses.

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A Study on the Heavy Metals Concentrations in the Air of the Dental Laboratories, in the Blood and Urine of Dental Laboratory Technicians (치과기공실 공기중 및 치과기공사의 혈액, 요중 중금속 함량에 관한 연구)

  • Cha, Sung-Soo
    • Journal of Technologic Dentistry
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    • v.10 no.1
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    • pp.11-24
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    • 1988
  • The purpose of this study was to determine the concentration of cadmium, nickel and chromium in the air of the work-place, blood of and urine of workers and compare the level of those heavy metals by the duration of work, work-place, process of work, smoking and other factors. In this study, 48 male dental laboratory technicans and 72 office workers as the control group were subjected. The concentration of cadmium, nickel and chromium in their blood sand urine, and that of heavy metals in the air of their work-rooms were examined and analyzed from June I 1987 to September 30, 1987. The results were as follows : 1. The concentration of cadmium in the air was the highest in the porcelain part, $0.0087{\pm}0.0016mg/m^3$, that of nickel was the highest in the crown bridge part, $0.4253{\pm}0.0052mg/m^3$, and that of chrnmium was highest in the partial denture part, $0.1063{\pm}0.0024mg/m^3$. 2. cadmium, nickel and chromium concentrations in the blood and urine of dental laboratory techincians were higher that in the office workers'. Especially the concentration of cadmium in the blood($1.92{\pm}1.23{\mu}g$/100ml) of th dental laboratory techician was about two times as high as that in the office workers'($0.90{\pm}0.73{\mu}g$/100ml), and the concentration of nickel in the urine($48.53{\pm}38.83{\mu}g$/e) of the dental laboratory thchnician was about two times as high as that in the office worker's($20.24{\pm}15.35{\mu}g$/e). 3. there was no difference in the concentration of cadmium, nickel and chromium in the blood and urine with a longer duration of work. 4. The concentration of cadmium and chromium in the blood and urine differed significantly depending upon the place of work. The concentration of cadmium was the highest in the blood of dental laboratory technicians working kin the poreclain part marking at $2.53{\pm}1.08{\mu}g$/100ml. The chromium level was the heighest in the blood of partial denture park workers with a concentration of $3.60{\pm}1.02{\mu}g$/100ml. Concerning the level of cadmium in urine, it was the highest in the porcelain part workers with a concentration of $3.41{\pm}3.15{\mu}g$/e. 5. The concentration of cadmium in the urine of metal trimming and polishing group($2.64{\pm}2.41{\mu}g$/e) was higher than that of non-metal trimming and polishing group($1.39{\pm}1.18{\mu}g$/e). 6. The concentration of chromium in the blood of smoking group($2.46{\pm}1.54{\mu}g$/100ml)was higher than that lf non-smoking group($1.54{\pm}1.25{\mu}g$/100ml). 7. The height positive correlation coefficient was shown between the concentration of nickel and chromium in the blood among the all correlations between 3metals(Cd, Ni, Cr) in the blood and those in urine. The correlation coefficient was relatively high(r=0.605,,p<0.01). In general, the higher the concentration of heavy metals in the air of work places the higher the concention lf them in the blood and urine of workers, mere attention should be paid to the working environment of dental laboratory workers, Furthermore, continuous biological monitoring and further research are required for an efficient health management for dental laboratory workers.

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Countermeasure and Outbreak Mechanism of Cochlodinium polykrikoides red tide 1. Environmental characteristics on outbreak and disappearanceof C. polykrikoides bloom (Cochlodinium polykrikoides 적조 발생기작과 대책 1. Cochlodinium polykrikoides 적조 발생과 소멸의 환경특성)

  • Park, Young-Tae;Kim, Young-Sug;Kim, Kui-Young;Park, Jong-Soo;Go, Woo-Jin;Jo, Yeong-Jo;Park, Seong-Yoon;Lee, Young-Sik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.4
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    • pp.259-264
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    • 2001
  • Typhoon and neap tide on Cochlodinium polykrikoides bloom and water temperature on disappearance of C. polykrikoides bloom were investigated to elucidate the outbreak mechanism of C. polykrikoides blooms at Naro and Namhae coastal area in South Sea of Korea. The first observation of C. polykrikoides blooms were observed when thermocline was disappeared by typhoon, tide, etc. The first blooms of C. polykrikoides were observed on neap tide or before one day from neap tide in 1996-1998 and 2000. However, thermocline was disappeared by typhoon in 1994 and 1999, the first blooms were observed early 12-30 day than 1996-1998 and 2000. The main reason of disappearance of C. polykrikoides blooms after typhoon on 1997-2000 seems to be other environmental change by typhoon rather than low water temperature. In the future, the first C. polykrikoides bloom will be appear around the first neap tide of latter part of August with breaking down of thermocline, but if the thermocline be collapsed by typhoon in July, the C. polykrikoides bloom will be appear at beginning of August. The outbreak of C. polykrikoides blooms will be explain as follows: The vegetative cells, which was germinated by environmental change or already exist in surface water at low level, input to the surface water, and then nutrients and trace metals which were suppled from out side of C. polykrikoides bloom area inflow to surface. The vegetative cells are growth by the nutrients and trace metals at suitable environmental conditions e.g. water temperature, salinity, and sufficient light.

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