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Effects of Anti-thyroglobulin Antibody on the Measurement of Thyroglobulin : Differences Between Immunoradiometric Assay Kits Available (면역방사계수법을 이용한 Thyroglobulin 측정시 항 Thyroglobulin 항체의 존재가 미치는 영향: Thyroglobulin 측정 키트에 따른 차이)

  • Ahn, Byeong-Cheol;Seo, Ji-Hyeong;Bae, Jin-Ho;Jeong, Shin-Young;Yoo, Jeong-Soo;Jung, Jin-Hyang;Park, Ho-Yong;Kim, Jung-Guk;Ha, Sung-Woo;Sohn, Jin-Ho;Lee, In-Kyu;Lee, Jae-Tae;Kim, Bo-Wan
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.4
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    • pp.252-256
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    • 2005
  • Purpose: Thyroglobulin (Tg) is a valuable and sensitive tool as a marker for diagnosis and follow-up for several thyroid disorders, especially, in the follow-up of patients with differentiated thyroid cancer (DTC). Often, clinical decisions rely entirely on the serum Tg concentration. But the Tg assay is one of the most challenging laboratory measurements to perform accurately owing to antithyroglobulin antibody (Anti-Tg). In this study, we have compared the degree of Anti-Tg effects on the measurement of Tg between availale Tg measuring kits. Materials and Methods: Measurement of Tg levels for standard Tg solution was performed with two different kits commercially available (A/B kits) using immunoradiometric assay technique either with absence or presence of three different concentrations of Anti-Tg. Measurement of Tg for patient's serum was also performed with the same kits. Patient's serum samples were prepared with mixtures of a serum containing high Tg levels and a serum containg high Anti-Tg concentrations. Results: In the measurements of standard Tg solution, presence of Anti-Tg resulted in falsely lower Tg level by both A and B kits. Degree of Tg underestimation by h kit was more prominent than B kit. The degree of underestimation by B kit was trivial therefore clinically insignificant, but statistically significant. Addition of Anti-Tg to patient serum resulted in falsely lower Tg levels with only A kit. Conclusion: Tg level could be underestimated in the presence of anti-Tg. Anti-Tg effect on Tg measurement was variable according to assay kit used. Therefore, accuracy test must be performed for individual Tg-assay kit.

A clinical study of allergic rhinitis (알레르기 비염에 관한 임상적 연구)

  • 채병윤
    • The Journal of Korean Medicine
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    • v.21 no.3
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    • pp.149-165
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    • 2000
  • As recent developments of Immunology and Nuclear medicine, serum IgE and IgG values are helpful in the diagnosis and evaluation of the therapeutic effects of nasal allergies. But in Korea, air pollution and the increased use of food additives have become leading factors in nasal allergies, It seems to be induced by environmental change, especially industrialization and urbanization, so allergic rhinitis in our environment has changed in accordance with the changes made in the living environment. Therefore this study is attempted in order to observe a clinical analysis which places more importance on allergic rhinitis. We studied 200 patients who had visited Kyunghee Oriental Medical Center with allergic rhinitis from January 1, 1999 to December 31, 1999 The results were as follows: 1. The sex distribution was 114 males(57%) and 86 females(43%). In age distribution, the average age was 25. In males, ages ranged from 3 to 66 years old and the average was 23.81. In females, ages ranged from 4 to 67 years old and the average was 28.57. The peak age was 30~39 years old(24%); under 9 years old and 10~19 years old were each 18%; 20~29 years old was 22%; 40~49 years old was 11 %; over 50 years old 6.5%. The gulf between males and females showed a statistically significant difference(P<0.025). 2. In the age of onset, male' s maximum was 62.5, minimum was 0.25; female s maximum was 59.5, minimum was 0.2. Under 9 years old was the most with 34%(male 24%, female 10%), 10~19 years old was 18%, 20~29 years old was 22.5%, 30~39 years old was 13.50%, over 40 years old was 12%, The gulf between males and females were showed statistically significant difference.(p<0.014) 3. The average duration of the disease was 5.67 years. In male and female, the maximum was 30, the minimum was 0.05; under 5 years old was the most with 62%(male 34.50%, female 27.50%); 6~10 years old was 23%. So, under 10 years old was 85%. There was no statistically significant difference in the duration of disease. 4. Regarding type of residence, 47.50% of patients with allergic rhinitis lived in apartments, 52.50% lived in houses. In males, 29.50% lived in apartments, 27.50% lived in houses. In females, 18% lived in apartments, 25% lived in houses. There was no statistically significant difference in the residence by T-test and chi-test. 5. In the distribution of season, spring is the most with 29.5% of patients, winter 28%, fall 25.5%, and summer 17%. But there was no statistically significant difference. 6. After observing 200 patients with allergic rhinitis, classifying main symptoms into 5 types, sneezing was the main symptom in 177cases(88.50%), nasal obstruction in 176cases(88%), rhinorrhea in 169cases(84.5%), post nasal discharge in 87cases(43.50%), and itching in I04cases(52%). The Cumulus ration is 98.50% and symptoms overlapped with an average 3.57±0.1 times but in an analysis of variance of these symptoms, the gulf between males and females was not recognized as statistically significant by T-test and ANOVA. 7. Patients whose families have allergic diseases account for 90 cases(45%) : 49cases(24.50%) male and 41cases(20.50%) female. There were 4 cases (71.11 %) whose families have allergic rhinitis, 9cases(10%) of asthma, and 7.78% with allergic dermatitis. There were 61 (67.80%) cases of patients whose parents have allergic diseases; cases wherein the patient s child had allergic diseases numbered 13 (14.45%); and cases with a sibling with allergic diseases totalled 16cases (17.80%). There was no statistically significant difference in allergic disease regarding sex, parents, or siblings by chi-test. 8. Blood type: For males, type A is the most common, with 37cases(18.5%), followed by type B with 32cases(16%), type O 28cases(l4%) and type AB 13cases(6.5%). For females, type B is the most common, with 30cases(15%), followed by type O with 23cases(l1.5%), type A with 18cases(9%) and type AB with 13cases(6.5%). There was no statistically significant difference in blood type by chi-test. 9. In the selection of prefered food, most patients prefer cool food, with 98 such cases(49%), tepid food in 54cases(27%) and warm food in 48cases(24%). These showed a statistically significant difference in the selection of prefered food between males and females by chi-test(p<0.009). 10. The state of Past History was classified into II types. chronic hypertrophic rhinitis is the most common with 11cases (18.64%), tonsil and adenoid hypertrophy is 8cases(l3.56%), sinusitis is 6cases(10.17%), nasal septum deviation is 4cases, nasal polyp is 2cases, others are 10cases(l6.95%). No statistically significant difference in past history between males and females was shown, but a statistically significant difference was shown when males and females were compared with total cases by T-test(p<0.002, P<0.0008). 11. Regarding complications, 37 patients (28.91%) had sinusitis: 22cases(17.19%) in male, 15cases(11.72%) in female. Chronic hypertrophic rhinitis was found in 15cases(11.72%). Others are under 10%. There was no statistically significant difference in the type of complications between males and females, but a statistically significant difference was shown when males and females were compared with total cases by T-test(P<0.00l, P<0.007). 12. In the treatment, medication was used 1691 times, an average of 2.58 times. No.34 was used 370 times for 124 cases, an average of 2.98 times. No. 152 was used 318 times for 106 cases, an average of 3.00 times. No.151 was used 307 times for 97cases, an average of 3.16 times. No. 31 was used 117 times for 33 cases, an average of 3.55 times. No 25 was used 116 times for 33 cases, an average of 3.52 times. 13. In the duration of treatment, the most frequent is 1 week(69cases, 34.50%), the maximum is 20weeks, and the minimum is 1week. A treatment period of 2~3 weeks accounted for 32% of cases, a period of 4~5weeks accounted for 13.5%. The gulf between males and females showed a statistically significant difference in the duration of treatment.(p<0.01). There was a statistical significance when the males were compared with total cases by ANOVA(P<0.03). 14. A comparison between before-treatment and after-treatment showed a statistically significant difference in treatment by T-test (p<0.01) and F-test (p<0.0058).

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Inhibitory Effects of Amitriptyline, Sertraline and Chlorpromazine on the Thrombin-induced Aggregation of Platelets (Thrombin성 혈소판응집에 대한 Amitriptyline, Sertraline 및 Chlorpromazine의 억제작용)

  • Choi, Sang-Hyun;Lee, Young-Jae;Shin, Kyung-Ho;Chun, Yeon-Sook;Chun, Boe-Gwun
    • The Korean Journal of Pharmacology
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    • v.31 no.3
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    • pp.299-311
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    • 1995
  • Platelets resemble monoaminergic neurons in several respects, i.e. the uptake of 5-HT and its inhibition, the subcellular storage and release of 5-HT, and the metabolism of aromatic amines brought about by monoamine oxidase. And the 5-HT content of rabbit platelets is well known to be about 40 times higher than that of human platelets. Therefore, this study was carried out to investigate the influences of amitriptyline (AMT) and sertraline (SRT) on the aggregation, contents of signaling second messengers, and protein phosphorylations of rabbit platelets in response to thrombin, 0.25 unit/ml, comparing with those of chlorpromazine (CPZ). Thrombin-induced aggregation was inhibited by SRT $(IC50:4.37{\times}10^{-5}\;M)$, CPZ $(IC50:5.76{\times}10^{-5}\;M)$, and AMT $(IC50:1.15{\times}10^{-4}\;M)$, respectively, and the aggregation by A23187 $(1.0\;{\mu}M)$ or PMA (320 nM) was also inhibited by SRT, CPZ, and AMT. AMT, SRT, and CPZ had little affects on basal contents of platelet $TXB_2$ and $PGE_2$, but all of them inhibited the thrombin-induced increase of $TXB_2$. Thrombin did not change the platelet contents of cAMP and cGMP. CPZ, AMT, and SRT produced the slight decrease of basal cAMP content, and their effects were not affected by thrombin-treatment. But SRT and AMT moderately increased the basal cGMP content, and the cGMP content of thrombin-stimulated platelets was gradually increased by the pretreatment with SRT, AMT, and CPZ. Particularly, the SRT-dependent increase of the cGMP content was notable. Platelet $Ins(1,4,5)P_3$ content was rapidly increased up to a plateau within 10 sec after thrombin-stimulation, AMT, SRT, and CPZ increased the basal $Ins(1,4,5)P_3$ content, and the thrombin-dependent increase was enhanced by pretreatment with CPZ and AMT, but was blunted by SRT. Platelet $[Ca^{2+}]_i$, was rapidly increased up to a peak level within 20 sec after thrombin-stimulation. The increase of $[Ca^{2+}]_i$ was sisnificantly inhibited by AMT, SRT, and CPZ. Thrombin- or PMA-induced phosphorylations of platelet $41{\sim}43\;kDa$ and 20 kDa proteins were significantly inhibited by AMT, SRT, and CPZ. These results suggest that the antiplatelet activities of AMT and CPZ may be considerably attributed to the inhibition of protein kinase C activity, and the activity of SRT may be associated with the inhibitory effect on the thrombin-induced increase of $Ins(1,4,5)P_3$ and the increasing effect on the cGMP content of ptatelets. Therefore, it seems to be evident that AMT and SRT may produce their antidepressant activity, at least, partly through the inhibition of protein kinase C activity or the increase of resting $Ins(1,4,5)P_3$, content and in case of SRT, to a lesser extent, via the increase of cGMP in the brain.

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Feed Intake Evaluation of Korean Cattle (Hanwoo) Fed Diets Containing Different Levels of Compound Fattening Periods (한우의 육성 및 비육기간중 배합사료 급여 수준에 따른 사료섭취량 조사)

  • Shin, K.J.;Oh, Y.G.;Lee, S.S.;Kim, K.H.;Kim, C.H.;Paik, B.H.
    • Journal of Animal Science and Technology
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    • v.44 no.1
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    • pp.95-104
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    • 2002
  • A study was conducted to evaluate feed intake of Hanwoo bulls and steers fed diets of compound feed and rice straw. Twenty bull calves and sixty steers at 5 to 7 months old were used. The experimental period was divided into three feeding stages which are growing period (〈300 kg body weight (BW)), early fattening period (300-450 kg BW) and late fattening period (〉450 kg BW). The animals were given the diets containing 14.1% crude protein (CP) and 70.0% total digestible nutrients (TDN) in the growing period, 12.1% CP and 70.6% TDN in the early fattening period, and 11.2% CP and 71.9% TDN in the late fattening period, respectively. Experiment 1 was designed to compare feed intake (as-fed basis) between Hanwoo bulls and steers fed the experimental diets ad libitum. In Experiment 2, Hanwoo steers were allocated in one of three compound feed feeding treatments to investigate feed intake (as-fed basis). The treatment groups were ① feeding level 1 group fed compound feed ad libitum through the whole periods; ② feeding level 2 group fed 1.0% compound feed per kg BW in the growing period, 1.5% compound feed per kg BW in the early fattening period and compound feed ad libitum in the late fattening period; and ③ feeding level 3 group fed 1.5% compound feed per kg BW in the growing period, 2.0% compound feed per kg BW in the early fattening period and compound feed ad libitum in the late fattening period. In Experiment 1, the average daily feed intake of bulls increased linearly through the whole experimental period while the feed intake of steers increased until their body weight was reached upto 521 kg, afterward reduced. Average daily feed intake was about 3.5% per kg BW of both bulls and steers at the beginning (150 kg BW) of Experiment 1 while bulls and steers at 600 kg BW consumed the diets of 2.0 and 1.5% per kg BW, respectively. In Experiment 2, the average daily feed intake of steers in the feeding level 1 group gradually increased through the growing and early fattening periods and then steadily reduced over the late fattening period. The average daily feed intake in the feeding level 2 group linearly increased through the whole period while the feed intake in the feeding level 3 group showed a relatively rapid increase and reached a peak at 455 kg BW, and then sharply dropped. The average daily feed intake of steers in the feeding level 1 at the beginning (150 kg BW) of Experiment 2 was about 3.5% per kg BW but there was a reduction (1.5% per kg BW) at 600 kg BW. Besides, The feed intake of steers in the feeding level 2 and 3 in which compound feed was given with limitation increased to 2.0-3.0% per kg BW in the growing period and then reduced to 1.5-2.0% per kg BW. The limited compound feed feeding of steers in Experiment 2 resulted in higher rice straw intakes up to two to three folds and two folds in the growing and early fattening periods, respectively, than the ad libitum feeding.

The Prevalence of Obesity and Underweight in Adolescents in Incheon Area and the Relationship between Serum Cholesterol Level and Obesity (인천지역 청소년의 비만도와 혈청 콜레스테롤치와의 관계)

  • Kim, Myung Hyun;Kim, Tae Wan;Hong, Young Jin;Son, Byong Kwan;Pai, Soo Hwan;Chang, Kyung Ja;Kim, Soon Ki
    • Clinical and Experimental Pediatrics
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    • v.45 no.2
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    • pp.174-182
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    • 2002
  • Purpose : The purpose of this study was to investigate the prevalence of obese and underweight adolescents in Incheon area and to examine the relationship between serum cholesterol level and obesity, then to assess the nutritional condition of adolescents. Methods : With a questionnaire regarding their demographic characteristics, blood samples were obtained from apparently healthy students aged 12 to 24 years by venipuncture at April and May, 2000. We measured the obesity index using standard body weight and the body mass index(BMI) according to the criteria established by the Korean Pediatric Society in 1998. Obesity was defined as BMI more than 95 percentile, and underweight less than 15 percentile by age and sex. Results : A total of 1,456 students(M : F=685 : 771) aged 12 to 24 years were included in this study. The prevalence of obesity by standard body weight in adolescents in Incheon were 11.7% : mild obesity 6.5%, moderate 4.6%, and severe 0.5%. By BMI, the prevalence of obesity was 6.4% in males and 6.2% in females. In males, the prevalence of obesity in rural areas was 8.5%, lower than in urban areas(14.3%). The prevalence of underweight by obesity index was 34.1% in rural areas and 22.9% in urban areas. In females, the prevalence of obesity was 12.5% in rural areas and 19.6% in urban areas. There were no significant differences between the two regions(P=0.529). The prevalence of obesity increased with age till 16.3% of peak prevalence in 16 years of age, and then decreased. In males, the prevalence of obesity in academic and vocational school were 13.7% and 9.7%, respectively(P=0.116). In females of the academic and vocational school, the prevalence of obesity was 6.8% and 18.0%, respectively(P=0.001). In obese adolescents, serum total cholesterol was over 200 mg/dL in 6.2%. Conclusion : This study revealed that the prevalence of obesity in adolescents was about 12% and that the prevalence of underweight adolescents was considerably high. We think nutritional assessment and intervention are warranted for adolescent students.

The Storage Stability of Semi-Salted and Dried Mackerel by Free-Oxygen Absorber (탈산소제에 의한 반염건고등어 저장중의 품질안정성)

  • LEE Eung-Ho;CHUNG Young-Hoon;JOO Dong-Sik;KIM Jeong-Hee;OH Kwang-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.131-138
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    • 1985
  • The preservative effect of modified-atmosphere storage on the shelf-life of packed semi-salted and dried mackerel, Scomber japonicus, was examined. The semi-salted and dried mackerel fillets were packed in laminated plastic film bags (polyester/nylon/casted polypropylene: $12{\mu}m/15{\mu}m/60{\mu}m,\;15{\times}16cm$) filled with air (control, C), nitrogen gas (N), deoxygenized air (O) prepared by using free-oxygen absorber enclosed in the bag, in vacuum(V), and stored at $5^{\circ}C$. The quality of packed sample during the storage were examined in terms of viable cell counts of bacteria, thiobarbituric acid(TBA) value, perozide value(POV), volatile basic nitrogen(VBN), trimethylamine(TMA), adenosine triphosphate(ATP) and its related compounds and sensory evaluation. The results obtained are as follows: The pH of all the samples was in the range of $6.1{\pm}0.2$, and the contents of VBN and amino nitrogen of them increased during storage. In color values, L value(lightness) decreased while a and b values (red and yellow) revealed a tendency to increase during storage. The viable cell counts of the control sample(C) increased to $3.0{\times}10^6/g$ after 15 days storage but those of the other samples(V, N and O)were in the range of $2{\sim}6{\times}10^5/g$ after 20 days storage. The content of TMA increased during storage, but the histamine content showed a little change during storage and its content of all samples were less than 16 mg/100g. The inosinic acid(IMP) was rapidly degraded while inosine and hypoxanthine increased during storage. The TBA value of the control(C) reached a peak in 9 days and then decreased gradually while that of the sample(O) showed a little change during storage. The changes in POV of all the samples during storage showed a similar tendency to the TBA value. Fatty acid composition of raw mackerel consists of $35.6\%$ of saturated acid, $30.3\%$ of monoenoic acid and $34.2\%$ of polyenoic acid. The major fatty acid of the sample products were oleic acid($C_{18:1}$), palmitic acid($C_{16:0}$), docosahexaenoic acid($C_{22:6}$). The contents of polyenoic acid such as $C_{22:6},\;C_{20:5}$ decreased during storage while the other fatty acids showed a little change. From the results of sensory evaluation, the shelf-life of the control sample(C) was about 7 days and that of sample(V), (N) and (O) was about 15 days. It was concluded that deoxygenized atmosphere(free-oxygen absorber enclosed in the bag) was a good condition for preserving the quality of semi-salted and dried mackerel.

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Construction of Event Networks from Large News Data Using Text Mining Techniques (텍스트 마이닝 기법을 적용한 뉴스 데이터에서의 사건 네트워크 구축)

  • Lee, Minchul;Kim, Hea-Jin
    • Journal of Intelligence and Information Systems
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    • v.24 no.1
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    • pp.183-203
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    • 2018
  • News articles are the most suitable medium for examining the events occurring at home and abroad. Especially, as the development of information and communication technology has brought various kinds of online news media, the news about the events occurring in society has increased greatly. So automatically summarizing key events from massive amounts of news data will help users to look at many of the events at a glance. In addition, if we build and provide an event network based on the relevance of events, it will be able to greatly help the reader in understanding the current events. In this study, we propose a method for extracting event networks from large news text data. To this end, we first collected Korean political and social articles from March 2016 to March 2017, and integrated the synonyms by leaving only meaningful words through preprocessing using NPMI and Word2Vec. Latent Dirichlet allocation (LDA) topic modeling was used to calculate the subject distribution by date and to find the peak of the subject distribution and to detect the event. A total of 32 topics were extracted from the topic modeling, and the point of occurrence of the event was deduced by looking at the point at which each subject distribution surged. As a result, a total of 85 events were detected, but the final 16 events were filtered and presented using the Gaussian smoothing technique. We also calculated the relevance score between events detected to construct the event network. Using the cosine coefficient between the co-occurred events, we calculated the relevance between the events and connected the events to construct the event network. Finally, we set up the event network by setting each event to each vertex and the relevance score between events to the vertices connecting the vertices. The event network constructed in our methods helped us to sort out major events in the political and social fields in Korea that occurred in the last one year in chronological order and at the same time identify which events are related to certain events. Our approach differs from existing event detection methods in that LDA topic modeling makes it possible to easily analyze large amounts of data and to identify the relevance of events that were difficult to detect in existing event detection. We applied various text mining techniques and Word2vec technique in the text preprocessing to improve the accuracy of the extraction of proper nouns and synthetic nouns, which have been difficult in analyzing existing Korean texts, can be found. In this study, the detection and network configuration techniques of the event have the following advantages in practical application. First, LDA topic modeling, which is unsupervised learning, can easily analyze subject and topic words and distribution from huge amount of data. Also, by using the date information of the collected news articles, it is possible to express the distribution by topic in a time series. Second, we can find out the connection of events in the form of present and summarized form by calculating relevance score and constructing event network by using simultaneous occurrence of topics that are difficult to grasp in existing event detection. It can be seen from the fact that the inter-event relevance-based event network proposed in this study was actually constructed in order of occurrence time. It is also possible to identify what happened as a starting point for a series of events through the event network. The limitation of this study is that the characteristics of LDA topic modeling have different results according to the initial parameters and the number of subjects, and the subject and event name of the analysis result should be given by the subjective judgment of the researcher. Also, since each topic is assumed to be exclusive and independent, it does not take into account the relevance between themes. Subsequent studies need to calculate the relevance between events that are not covered in this study or those that belong to the same subject.

A STUDY ON THE TEMPERATURE CHANGES OF BONE TISSUES DURING IMPLANT SITE PREPARATION (임플랜트 식립부위 형성시 골조직의 온도변화에 관한 연구)

  • Kim Pyung-Il;Kim Yung-Soo;Jang Kyung-Soo;Kim Chang-Whe
    • The Journal of Korean Academy of Prosthodontics
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    • v.40 no.1
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    • pp.1-17
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    • 2002
  • The purpose of this study is to examine the possibility of thermal injury to bone tissues during an implant site preparation under the same condition as a typical clinical practice of $Br{\aa}nemark$ implant system. All the burs for $Br{\aa}nemark$ implant system were studied except the round bur The experiments involved 880 drilling cases : 50 cases for each of the 5 steps of NP, 5 steps of RP, and 7 steps of WP, all including srew tap, and 30 cases of 2mm twist drill. For precision drilling, a precision handpiece restraining system was developed (Eungyong Machinery Co., Korea). The system kept the drill parallel to the drilling path and allowed horizontal adjustment of the drill with as little as $1{\mu}m$ increment. The thermocouple insertion hole. that is 0.9mm in diameter and 8mm in depth, was prepared 0.2mm away from the tapping bur the last drilling step. The temperatures due to countersink, pilot drill, and other drills were measured at the surface of the bone, at the depths of 4mm and 8mm respectively. Countersink drilling temperature was measured by attaching the tip of a thermocouple at the rim of the countersink. To assure temperature measurement at the desired depths, 'bent-thermocouples' with their tips of 4 and 8mm bent at $120^{\circ}$ were used. The profiles of temperature variation were recorded continuously at one second interval using a thermometer with memory function (Fluke Co. U.S.A.) and 0.7mm thermocouples (Omega Co., U.S.A.). To simulate typical clinical conditions, 35mm square samples of bovine scapular bone were utilized. The samples were approximately 20mm thick with the cortical thickness on the drilling side ranging from 1 to 2mm. A sample was placed in a container of saline solution so that its lower half is submerged into the solution and the upper half exposed to the room air, which averaged $24.9^{\circ}C$. The temperature of the saline solution was maintained at $36.5^{\circ}C$ using an electric heater (J. O Tech Co., Korea). This experimental condition was similar to that of a patient s opened mouth. The study revealed that a 2mm twist drill required greatest attention. As a guide drill, a twist drill is required to bore through a 'virgin bone,' rather than merely enlarging an already drilled hole as is the case with other drills. This typically generates greater amount of heat. Furthermore, one tends to apply a greater pressure to overcome drilling difficulty, thus producing even greater amount heat. 150 experiments were conducted for 2mm twist drill. For 140 cases, drill pressure of 750g was sufficient, and 10 cases required additional 500 or 100g of drilling pressure. In case of the former. 3 of the 140 cases produced the temperature greater than $47^{\circ}C$, the threshold temperature of degeneration of bone tissue (1983. Eriksson et al.) which is also the reference temperature in this study. In each of the 10 cases requiring extra pressure, the temperature exceeded the reference temperature. More significantly, a surge of heat was observed in each of these cases This observations led to addtional 20 drilling experiments on dense bones. For 10 of these cases, the pressure of 1,250g was applied. For the other 10, 1.750g were applied. In each of these cases, it was also observed that the temperature rose abruptly far above the thresh old temperature of $47^{\circ}C$, sometimes even to 70 or $80^{\circ}C$. It was also observed that the increased drilling pressure influenced the shortening of drilling time more than the rise of drilling temperature. This suggests the desirability of clinically reconsidering application of extra pressures to prevent possible injury to bone tissues. An analysis of these two extra pressure groups of 1,250g and 1,750g revealed that the t-statistics for reduced amount of drilling time due to extra pressure and increased peak temperature due to the same were 10.80 and 2.08 respectively suggesting that drilling time was more influenced than temperature. All the subsequent drillings after the drilling with a 2mm twist drill did not produce excessive heat, i.e. the heat generation is at the same or below the body temperature level. Some of screw tap, pilot, and countersink showed negative correlation coefficients between the generated heat and the drilling time. indicating the more the drilling time, the lower the temperature. The study also revealed that the drilling time was increased as a function of frequency of the use of the drill. Under the drilling pressure of 750g, it was revealed that the drilling time for an old twist drill that has already drilled 40 times was 4.5 times longer than a new drill The measurement was taken for the first 10 drillings of a new drill and 10 drillings of an old drill that has already been used for 40 drillings. 'Test Statistics' of small samples t-test was 3.49, confirming that the used twist drills require longer drilling time than new ones. On the other hand, it was revealed that there was no significant difference in drilling temperature between the new drill and the old twist drill. Finally, the following conclusions were reached from this study : 1 Used drilling bur causes almost no change in drilling temperature but increase in drilling time through 50 drillings under the manufacturer-recommended cooling conditions and the drilling pressure of 750g. 2. The heat that is generated through drilling mattered only in the case of 2mm twist drills, the first drill to be used in bone drilling process for all the other drills there is no significant problem. 3. If the drilling pressure is increased when a 2mm twist drill reaches a dense bone, the temperature rises abruptly even under the manufacturer-recommended cooling conditions. 4. Drilling heat was the highest at the final moment of the drilling process.

Bioacoustics and Habitat Environment Analysis of Cicadas in Taebaeksan National Park (태백산국립공원에 서식하는 매미류의 생물음향 및 서식환경 분석)

  • Kim, Yoon-Jae;Jung, Tae-Jun;Ki, Kyong-Seok
    • Korean Journal of Environment and Ecology
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    • v.33 no.6
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    • pp.664-676
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    • 2019
  • This study aimed to analyze the bioacoustics and habitat environment of the cicadas inhabiting Taebaeksan National Park, an sub-alpine region in Korea. The mating calls of the cicadas were recorded for approximately 3 months, between July and September of 2018. The recording devices were installed in Daedeoksan valley and Baekcheon valley, inside Taebaeksan National Park, and the sounds were recorded 24 hours a day. In order to obtain the habitat distribution data of the cicadas, the sounds were recorded from 111 spots located in the Taebaeksan National Park trail in August 2018. The daily weather data was obtained from the Taebaek city weather center. The results of the study demonstrated that 5 species of cicadas inhabit Taebaeksan National Park, namely, Leptosemia takanonis, Lyristes intermedius, Kosemia yezoensis, Hyalessa fuscata, and Meimuna opalifera. The time of appearance for L. takanonis was early July to mid-July, and that for L. intermedius, K. yezoensis, H. fuscata, and M. opalifera was mid-July to early September. Analysis of the circadian rhythm revealed that L. intermedius, K. yezoensis, and H. fuscata started producing mating calls between 6:00 and 7:00, which ended at around 19:00 for all the three species. The peak time for producing mating calls was 11:00 for L. intermedius, 12:00 for H. fuscata, and around 13:00 to 14:00 for K. yezoensis. The environmental factors influencing the mating calls of the cicadas inhabiting Taebaeksan National Park were analyzed by logistic regression. The results showed that the probability of producing mating calls increased by 1.192 and 1.279 times in L. intermedius and K. yezoensis, respectively, when the average temperature increased by one degree. When the duration of sunlight increased by one hour, the probability of producing mating calls increased by 4.366 and 2.624 times in L. intermedius and H. fuscata, respectively. Analysis of the interspecific effects revealed that when H. fuscata produced a single mating call, the probability of producing mating calls increased by 14.620 and 2.784 times in L. intermedius and K. yezoensis, respectively. When K. yezoensis and L. intermedius produced mating calls, the probability of producing mating calls in H. fuscata increased by 11.301 and 2.474 times, respectively. L. intermedius and K. yezoensis did not have any effects on each other with respect to the production of mating calls. Analysis of the habitat environment of each species revealed that their habitats were located at altitudes of 1,046 m (780~1,315 m) for L. intermedius, 1,072 m (762~1,361 m) for K. yezoensis, and 976 m (686~1,245 m) for H. fuscata. Unlike H. fuscata, which was found at a low altitude, K. yezoensis and L. intermedius were not found at altitudes lower than 700 m. Analysis of the average aspect of the habitats of each of the cicada species revealed that L. intermedius was found at 166° (125~207°), K. yezoensis was found at 100° (72~128°), and H. fuscata was found at 173° (118~228°). Examination of the distribution of each of the cicada species revealed that they were predominantly distributed in the ridges and slopes located in the southeastern region of Munsubong in Taebaeksan. In summary, L. intermedius and K. yezoensis was found to inhabit higher altitudes in Taebacksan National Park than H. fuscata, which was found throughout the Korean peninsula. Additionally, the main aspect of the cicada habitat was found to be the southeastern region (100~173°), which has good access to daylight.

A Study on the Nonpoint Pollutant Loadings in Urban and Agricultural Areas (도시(都市)와 농촌(農村)에서의 비점원(非點源) 오염물(汚染物) 배출양상(排出樣相)에 관한 연구(硏究))

  • Lim, Bong Su;Lee, Byung Hyun;Choi, Eui So
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.4 no.2
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    • pp.45-53
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    • 1984
  • This study was conducted to investigate characteristics of nonpoint pollutant discharges and concentrations in runoff from the urban and agricultural areas in Korea. The analytical parameters used for this study were COD, BOD and SS. This study was conducted during the period from May to August 1981. Nonpoint pollutant mass loadings from the urban area were influenced by the rainfall intensity and the duration of rainfall, and etc. The concentrations of pollutants in the first flush was higher as the discharges increased. It was, however, found that the concentrations of pollutants in the heavy storm runoff were decreased due to the dilution effect. When other rainfall followed a peak rainfall, the concentrations of pollutants were lower than expected, because the first flush conveyed the most of pollutants deposited on the combined sewers. However the concentrations were increased in proportion to the increased flow when a rainfall of higher intensity than the first flush was continued. Yearly area yield rates in kg/ha were estimated to be 690.5(489.9~1,328) of COD, 319.7(226.8~614.8) of BOD, and 831.2(589.7~1,598) of SS. Pollutant sources in agricultural area were of the domestic waste water, manure composting stack, and agricultural solid wastes and etc. In the paddy field, yearly area yield rates in kg/ha were estimated to be 623.4(21.7~114) of COD, 18.65(9.53~34.5) of BOD, and 91.9(46.3~171.8) of SS. In the crop land, however, yearly rates in kg/ha were estimated to be 91.9(46.3~171.8) of COD, 23.09(11.7~42.5) of BOD, and 23.09(11.4~43.4) of SS. Pollutant sources in the feedlot area were originating from the feces of cattle, the cleaning water, the wastes spilled from manure composting stack during rain. Yearly area yield rate in kg/ha was estimated to be 3.804(2,489~6,658) of COD, 2.047(464~2,900) of BOD, and 1.149 (729~1,442) of SS. Pollutant discharges in the forest area were resulted from the organic layer like leaves and others deposited on the surface. Yearly area yield rate in kg/ha was estimated to be 9.86(5.45~18.56) of COD, 3.48(1.67~7.54) of BOD, and 4.64(9.74~10.35) of SS.

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