• 대한치과교정학회지
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• 제51권4호
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• pp.250-259
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• 2021

Objective: The aim of this study was to compare the differences in mandibular posterior anatomic limit (MPAL) distances stratified by vertical patterns in patients with skeletal Class III malocclusion by using cone-beam computed tomography (CBCT). Methods: CBCT images of 48 patients with skeletal Class III malocclusion (mean age, 22.8 ± 3.1 years) categorized according to the vertical patterns (hypodivergent, normodivergent, and hyperdivergent; n = 16 per group) were analyzed. While parallel to the posterior occlusal line, the shortest linear distances from the distal root of the mandibular second molar to the inner cortex of the mandibular body were measured at depths of 4, 6, and 8 mm from the cementoenamel junction. MPAL distances were compared between the three groups, and their correlations were analyzed. Results: The mean ages, sex distribution, asymmetry, and crowding in the three groups showed no significant differences. MPAL distance was significantly longer in male (3.8 ± 2.6 mm) than in female (1.8 ± 1.2 mm) at the 8-mm root level. At all root levels, MPAL distances were significantly different in the hypodivergent and hyperdivergent groups (p < 0.001) and between the normodivergent and hyperdivergent groups (p < 0.01). MPAL distances were the shortest in the hyperdivergent group. The mandibular plane angle highly correlated with MPAL distances at all root levels (p < 0.01). Conclusions: MPAL distances were the shortest in patients with hyperdivergent patterns and showed a decreasing tendency as the mandibular plane angle increased. MPAL distances were significantly shorter (~3.16 mm) at the 8-mm root level.

• The Journal of Advanced Prosthodontics
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• 제16권2호
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• pp.77-90
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• 2024

PURPOSE. The study aims to investigate the influence of the ferrule effect and types of posts on the stress distribution in three morphological types of the maxillary central incisor. MATERIALS AND METHODS. Nine models were created for 3 maxillary central incisor morphology types: "Fat" type - crown 12.5 mm, root 13 mm, and buccolingual cervical diameter 7.5 mm, "Medium" type - crown 11 mm, root 14 mm, and buccolingual cervical diameter 6.5 mm, and "Slim" type - crown 9.5 mm, root 15 mm, and buccolingual cervical diameter 5.5 mm. Each model received an anatomical castable post-and-core or glass-fiber post with resin composite core and three ferrule heights (nonexistent, 1 mm, and 2 mm). Then, a load of 14 N was applied at the cingulum with a 45° slope to the long axis of the tooth. The Maximum Principal Stress and the Minimum Principal Stress were calculated in the root dentin, crown, and core. RESULTS. Higher tensile and compression stress values were observed in root dentin using the metallic post compared to the fiber post, being higher in the slim type maxillary central incisor than in the medium and fat types. Concerning the three anatomical types of maxillary central incisors, the slim type without ferrule height in mm presented the highest tensile stress in the dentin, for both types of metal and fiber posts. CONCLUSION. Post system and tooth morphology were able to modify the biomechanical response of restored endodontically-treated incisors, showing the importance of personalized dental treatment for each case.

• 한국산림과학회지
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• 제101권4호
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• pp.599-605
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• 2012

본 연구의 목적은 굴참나무 임분의 직경분포와 ha당 재적 및 탄소량을 추정하는데 있다. 영급과 임분구조를 고려하여 굴참나무 임분에서 354개소를 조사하고 시료를 수집하였다. 임령에 따른 직경분포를 파악하기 위하여 Weibull 모형을 사용하였으며 모수의 추정은 단순적률법(Simplified method-of-moments)을 이용하였다. 사용된 자료 중에서 80%는 모형개발에 사용하였고, 나머지 20%는 개발된 모형의 검정에 사용하였다. 모형의 검정에는 적합도지수(Fitness Index)와 평균오차제곱(Root Mean Square Error), Kolmogorov-Smirnov 통계치가 이용되었다. 검정자료에서 추정된 지위지수, 수고, 재적식의 적합도지수는 각각 0.967, 0.727, 0.988이고 평균오차제곱은 2.763, 1.817, 0.007이며, Weibull 모형의 Kolmogorov-Smirnov 적합도는 75%를 나타내었다. 본 연구를 통해 개발된 모형에서 50년생의 굴참나무임분이 14의 지위지수와 697본의 분수를 나타내는 경우, 재적은 $188.69m^3/ha$이고 지상부 탄소량은 90.30 tC/ha으로 추정되었다. 본 연구의 결과는 활엽수 수종에 대한 생장정보의 제공이 가능하고 굴참나무 탄소량 추정에 활용이 가능하다.

• 치과방사선
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• 제28권2호
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• pp.435-459
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• 1998

In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora/sup (R)/(digital imaging system) and Root ZX/sup (R)/(the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems. whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with #15, #20, #25 files by 3 different dentists each using the periapical radiography. Digora/sup (R)/ and Root ZX/sup (R)/. The measurements were then compared with the true length. The results were as follows: 1. In comparing mean discrepancies between measurements obtained by using periapical radiography(mean error: -0.449±0.444 mm), Digora/sup (R)/(mean error: -0.417±0.415 mm) and Root ZX/sup (R)/(mean error: 0.123±0.458 mm) with true length. periapical radiography and Digora/sup (R)/ system had statistically significant differences(p<0.05) in most cases while Root ZX/sup (R)/ showed none(p>0.05). 2. By subtracting values obtained by using periapical radiography, Digora/sup (R)/ and Root ZX/sup (R)/ from the true length and making a distribution table of their absolute values. the following analysis was possible. In the case of periapical film. 140 out of 261<53.6％) were clinically acceptable satisfying the margin of error of less than 0.5 mm. 151 out of 261 (53,6％) were acceptable in the Digora/sup (R)/ system while Root ZX/sup (R)/ had 197 out of 261(75.5％) within the limits of 0.5mm margin of error. 3. In determining whether the thickness of files has any effect on measuring methoths, no statistically significant differences were found(p>0.05). 4. In comparing data obtained from these methods in order to evaluate the difference among measuring methods, there was no statistically significant difference between periapical radiography and Digora/sup (R)/ system(p>0.05), but there was statistically significant difference between Root ZX/sup (R)/ and periapical radiography(p<0.05). Also there was statistically significant difference between Root ZX/sup (R)/ and Digora/sup (R)/ system(p<0.05). In conclusion, Root ZX/sup (R)/ was more accurate when compared with the Digora/sup (R)/ system and periapical radiography and seems to be more effective clinically in determining root canal length. But Root ZX/sup (R)/ has its limits in determining root morphology and number of roots and its accuracy becomes questionable when apical foramen is open due to unknown reasons. Therefore the combined use of Root ZX/sup (R)/ and the periapical radiography are mandatory. Digora/sup (R)/ system seems to be more effective when periapical radiographs are needed in a short period of time because of its short processing time and less exposure.

• 대한한의학원전학회지
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• 제30권1호
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• pp.51-55
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• 2017

Objectives : Though regional body temperature palpation is one of well stylized diagnosis methods in Huangdineijing, it has not been thoroughly reconstructed. So I tried to find and reconstruct the methods in Huangdineijing to diagnose regional body temperature as a objective sign. Material and Methods : Huangdineijing(in Zhonghuayidian) was used for text search. "Heat(熱)", "Cold and Heat(寒熱)", "Cold and Warmth(寒溫)", "Root and Terminal(本末)" was used as searching keywords. By classifying and analysing searched sentences I reconstructed the original palpation methods. Results : Two types of regional temperature palpation method was found in Huangdineijing. One is the method palpating the Root(origin) points and Terminal points of the meridians, while the other method is that palpating the skin in anterior side of forearm. It was proved that they had been collaboratively used to diagnose the diseases related to meridians and it's collaterals. Conclusions :In the era of Huangdineijing, there was at least two types of regional temperature palpation method and their clinical usage was in complementary relations.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.203-211
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• 1994

The establishment by seeds and the maintenance by ramets of the autumn olive (Elaeagnus umbellata) population were investigated in the Namhansansung Provincial Park, Jungbu-myun, Kwangju-gun, Kyunggi-do. Seed production and germination rate were 3, 300 $seeds{\cdot}m^{-2}{\cdot}yr^{-1}$ and 52%, respectively. The ramet formation in the population was classified into 4 types: stump type, creeping root type, lateral root type and secondary creeping root type. The subterranean creeping roots were 0.1~1.0 m in length, 4.5~14.0 mm in diameter and 0.06~0.2 m in soil depth. The number of ramets formed from a node was 1~21. The subterranean roots spread $5~509cm^2{\cdot}plant^{-1}{\cdot}yr^{-1}$, which began to be produced from 7~9 year-old individuals. The number of stems was 1~67 per stump, which was reduced by self-thinning from 2 to 14 year-old trees. The frequency distribution of stem diameter$(D_{30})$ showed a reverse J-shaped curve, suggesting that this population be maintained perpetually by their own ramets.

• Mycobiology
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• 제30권4호
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• pp.233-239
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• 2002

The main aim of this study is to evaluate the efficiency of two biologically active compounds(Strom and F-760) in control of wheat root rot disease and its causal organisms. Fusarium graminearum, F. oxysporum, F. solani and Bipolaris sorokiniana were used as target organisms. In vitro, the two compounds showed fungicidal effect on all investigated pathogens resulted in suppression of radial growth and mycelial dry weight of them. Under greenhouse conditions, treatment of wheat grains with either Strom or F-760 before cultivation significantly reduced the percent of disease distribution as well as the mean disease rating of plants in both seedling and flowering stages. Fresh and dry weights of plants as well as water maintenance capacity were increased as the result of applying these compounds as seed dressing. Also data showed that the membrane stability of plants was injured as a result of infection with all investigated organisms, while this injury was alleviated when F-760 and Strom were applied. The $K^+$ efflux and the leakage of UV absorbing metabolites was stimulated with fungal infection. However, F-760 and Storm treatment partially retarded the stimulatory effect on leakage of $K^+$ and UV-absorbing metabolites of fungal infected plants. On the other side, the fungal infection had inhibitory effects on pigment fractions(chlorophyll a, b, and carotenoids) biosynthesis in wheat leaves. This retarding effect was partially or completely alleviated as the grains were treated with the applied compounds.

• 한국환경과학회지
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• 제16권1호
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• pp.39-44
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• 2007

This study was conducted to investigate the contents of residual solvents and mineral components(11 kinds) in ginseng extracts with different extracting conditions(5 types) and commercial ginseng extract products(domestic, imported). Fine root was extracted with solution having various ethanol concentration after hexane treatment. Among 5 type extracts, residual solvent(hexane) was detected ginseng extracts treated ethanol mixed with hexane. But extracts that dried after soaked in hexane wasn't detected hexane. Mineral components(Al, Mn, Fe, Cu and Zn) were detected in fine root and 5 types of extracts. The contents of mineral components between fine root and extracts with various extracting conditions were similar, however, extracts that dried after soaked in hexane showed the lower amount in Al, Fe, Pb than the others. In comparison with commercial ginseng ex-tract products(domestic, imported), the distribution pattern of mineral was similar but the contents were a little different.

• 한국응용곤충학회지
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• 제52권3호
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• pp.255-259
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• 2013

온실에서 재배되는 수입 드라세나묘목 및 게발선인장에서 채집된 뿌리깍지벌레 2종 Ripersiella multiporifera Jansen 및 Rhizoecus albidus Goux를 우리나라에서 처음으로 보고한다. 이들은 수입된 식물을 통해 온실에 도입된 것으로 추정되며 우리나라에 추가적인 유입과 정착을 방지하기 위해 이들 종의 진단형질, 사진자료, 기주 및 분포정보를 제공하고자 한다.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.65-75
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• 2021

This study analyzes the validity of the Phillips curve with regards to Turkey. The existence and direction of the causality relationship (reason-outcome relationship) between unemployment and inflation is investigated using inflation and unemployment data for the period 1980-2019. Unit root tests were utilized to evaluate the stationarity of the series. In line with the Zivot-Andrews unit root test, which was developed in response to the criticism of the failure of studies that presented macro-variables like inflation to consider traditional unit root tests, in this research, the Engle-Granger cointegration test was implemented to check whether the series could perform a joint action, and, finally, the Granger causality relationship was explored. According to the results of the analysis, over the relevant period there was a single directional causality relationship from inflation toward unemployment in Turkey. The importance of this relationship at the 10% significance level indicates the existence of many different factors that affect inflation and unemployment. Given the existence of a cointegration and causality relationship between inflation and unemployment, it can be said that, in Turkey, the Phillips curve is valid for the period 1980-2019 and that an increase of 1% in inflation will reduce the unemployment rate by 0.028%.