• Korean Journal of Plant Taxonomy
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• v.36 no.4
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• pp.309-333
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• 2006

Examined were the vegetative and reproductive characters such as external morphology, anatomy (leaf petiole, blade and stem), pollen and nutlet for the taxonomic revision of Elsholtzia in Korea. The inflorescence of all studied taxa of Elsholtzia in Korea is secund and 0.5-10 cm long. Leaves are ovate or nearly and $0.2-10{\times}0.2-6.0cm$. The shapes of inflorescence and leaves are very useful taxonomic characters. The stomata types are anomocytic and diacytic. The morphology of nutlet is ovoid and pitted in surface pattern of exocarp. All studied taxa are myxocarpy. The pollen grains are of medium size and subprolate in shape, and have typical bi-reticulate exine surface. Four species are recognized for Korean Elsholtzia by the identification key and descriptions in this study.

• Restorative Dentistry and Endodontics
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• v.43 no.2
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• pp.16.1-16.9
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• 2018

Objectives: Understanding the reason for an unsuccessful non-surgical endodontic treatment outcome, as well as the complex anatomy of the root canal system, is very important. This study examined the cross-sectional root canal structure of mandibular first molars confirmed to have failed non-surgical root canal treatment using digital images obtained during intentional replantation surgery, as well as the causative factors of the failed conventional endodontic treatments. Materials and Methods: This study evaluated 115 mandibular first molars. Digital photographic images of the resected surface were taken at the apical 3 mm level and examined. The discolored dentin area around the root canal was investigated by measuring the total surface area, the treated areas as determined by the endodontic filling material, and the discolored dentin area. Results: Forty 2-rooted teeth showed discolored root dentin in both the mesial and distal roots. Compared to the original filled area, significant expansion of root dentin discoloration was observed. Moreover, the mesial roots were significantly more discolored than the distal roots. Of the 115 molars, 92 had 2 roots. Among the mesial roots of the 2-rooted teeth, 95.7% of the roots had 2 canals and 79.4% had partial/complete isthmuses and/or accessory canals. Conclusions: Dentin discoloration that was not visible on periapical radiographs and cone-beam computed tomography was frequently found in mandibular first molars that failed endodontic treatment. The complex anatomy of the mesial roots of the mandibular first molars is another reason for the failure of conventional endodontic treatment.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.462-467
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• 2018

Background: Significant discrepancy exists between anatomical plate designs and the anatomy of the native distal radius, which may be attributable to considerable morphometric variations in the volar aspect of the distal radius. We aimed to evaluate the degree of variability in the morphometry of the distal radius and identify factors associated with this variability. Methods: We measured the volar surface angle (VSA) of the intermediate and lateral columns and the volar surface width (VSW) in the distal radius from three-dimensional computed tomography scans acquired from 81 cadaveric forearms. These morphometric parameters were compared between the lateral and intermediate columns, between males and females, and between Koreans and Caucasians. Caucasian morphometric data were obtained and pooled from the previous studies. The coefficient of variation was used to assess the variability of the parameters and Cohen's d to estimate the effect size of the difference between groups. Results: The average VSA of the lateral column was $22^{\circ}{\pm}6^{\circ}$, and that of the intermediate column was $29^{\circ}{\pm}8^{\circ}$ in Koreans (p < 0.001). The variability was high for both VSAs. The VSA of the intermediate column was significantly larger in males than in females (p < 0.001) and in Caucasians than in Koreans (p < 0.001). The average VSW of distal radius was $30{\pm}3mm$ at the watershed line, and it became narrower proximally. The VSW was significantly larger in males than in females (p < 0.001) and in Koreans than in Caucasians (p < 0.001). The effect sizes of the difference for the VSA and VSW between sexes, races and columns were medium to large. Conclusions: Considerable variability exists in the morphometry of the volar distal radius, with sex, race, and column as contributing factors. These results suggest that surgeons should carefully choose an anatomical volar locking plate with appropriate angulation characteristics for each patient to achieve patient-specific alignment of the distal radius.

• Imaging Science in Dentistry
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• v.53 no.4
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• pp.325-333
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• 2023

Purpose: The objective of this study was to evaluate and compare the accuracy and image quality of root surface area (RSA) measurements obtained with various cone-beam computed tomography (CBCT) protocols, relative to the gold standard of micro-computed tomography (CT), in an in vitro setting. Materials and Methods: Four dry human skulls were scanned using 8 different protocols, with voxel sizes of 0.15 mm, 0.3 mm, and 0.4 mm. Three-dimensional models of the selected teeth were constructed using CBCT and microCT protocols, and the RSA was automatically measured by the image-processing software. The absolute difference in the percentage of the RSA(%ΔRSA) was calculated and compared across the 8 CBCT protocols using repeatedmeasures analysis of variance. Finally, image quality scores of the RSA measurements were computed and reported in terms of percent distribution. Results: No significant differences were observed in the %ΔRSA across the 8 protocols (P>0.05). The deviation in %ΔRSA ranged from 1.51% to 4.30%, with an increase corresponding to voxel size. As the voxel size increased, the image quality deteriorated. This decline in quality was particularly noticeable at the apical level of the root, where the distribution of poorer scores was most concentrated. Conclusion: Relative to CBCT protocols with voxel sizes of 0.15mm and 0.3mm, the protocols with a voxel size of 0.4 mm demonstrated inferior image quality at the apical levels. In spite of this, no significant discrepancies were observed in RSA measurements across the different CBCT protocols.

• Applied Science and Convergence Technology
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• v.25 no.3
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• pp.51-55
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• 2016

The surface treatment of a titanium implant is investigated with a non-thermal atmospheric pressure plasma jet. The plasma jet is generated by the injection of He and $O_2$ gas mixture with a sinusoidal driving voltage of 3 kV or more and with a driving frequency of 20 kHz. The generated plasma plume has a length up to 35 mm from the jet outlet. The wettability of 4 different titanium surfaces with plasma treatments was measured by the contact angle analysis. The water contact angles were significantly reduced especially for $O_2/He$ mixture plasma, which was explained with the optical emission spectroscopy. Consequently, plasma treatment enhances wettability of the titanium surface significantly within the operation time of tens of seconds, which is practically helpful for tooth implantation.

• Asian Spine Journal
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• v.12 no.6
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• pp.1123-1126
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• 2018

Study Design: Observational study. Purpose: To assess the correlational accuracy between the traditional anatomic landmarks of the neck and their corresponding vertebral levels in Southern Chinese patients. Overview of Literature: Recent studies have demonstrated discrepancies between traditional anatomic landmarks of the neck and their corresponding cervical vertebra. Methods: The center of the body of the hyoid bone, the upper limit of the lamina of the thyroid cartilage, and the lower limit of the cricoid cartilage were selected as representative surface landmarks for this investigation. The corresponding vertebral levels in 78 patients were assessed using computed tomography. Results: In both male and female patients, almost none of the anatomical landmarks demonstrated greater than 50% correlation with any vertebral level. The most commonly corresponding vertebra of the hyoid bone, the lamina of the thyroid cartilage, and the cricoid cartilage were the C4 (47.5%), C5 (35.9%), and C7 (42.3%), respectively, which were all different from the classic descriptions in textbooks. The vertebral levels corresponding with the thyroid and cricoid cartilage were significantly different between genders. Conclusions: The surface landmarks of the neck were not accurate enough to be used as the sole determinant of vertebral levels or incision sites. Intra-operative fluoroscopy is necessary to accurately locate each of the cervical vertebral levels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.560-567
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• 1991

Photosynthetic variation in field grown soybean [Glycine max (L.) Merr. cv Hodgson78］ was studied in relation to leaf anatomical variation. Variations in mesophyll morphology were accentuated by manipulating source and sink size. At R3 stage, two treatments were started: one was thinning and continu-ous debranching(6. 5 plants rather than 26 plants per m of row and remaining plants were debranched weekly), and the other was continuous partial depodding (allowing only one pod to develop at each mainstem node). Gas exchange characteristics, mesophyll cell volume and surface area per unit leaf surface, and microclimatic parameters were measured on the intact terminal leaflet at the 10th node. Observations were made 5 times with 3 to 4 day intervals starting R4 stage. Two models were used to compute leaf photosynthetic rates: one considered no effect of mesophyll morphology on photosynthesis, and the other considered potential effects of variations in mesophyll cell volume and surface area on diffusion and biochemical processes. Seventy nine percent of total photosynthetic variations observed in the experiment was explained by the latter, while 69% of the same variations was explained by the former model. By incorporating the mesophyll morphology concept, the predictability was improved by 14.6% in the field condition. Additional Index Words: photosynthesis model, leaf anatomy, Glycine max (L.) Merr., mesophyll surface area, mesophyll cell volume.

• The Korean Journal of Pain
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• v.22 no.1
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• pp.47-51
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• 2009

Background: The blind sacroiliac joint (SIJ) block cannot always be performed accurately; it is commonly performed in the office based setting because intraarticular and periarticular injections are effective for SIJ pain. However, knowledge on the surface anatomy of the SIJ is lacking. The purpose of this study was to analyze the surface anatomical location of the posterior-inferior margin of the SIJ. Methods: After informed consent was obtained, fifty patients undergoing SIJ block in the prone position were examined. The oblique angles where the anterior-inferior margin and the posterior-inferior margin of the SIJ overlap on X-ray were evaluated. In addition, the surface anatomical relationships between the posterior-inferior margin of the SIJ on X-ray and the posterior superior iliac spine (PSIS) and sacral hiatus by palpation were assessed. Results: The oblique angle was $5.4{\pm}2.9^{\circ}$. The vertical and transverse distance between the posterior-inferior margin of the SIJ and PSIS were $3.8{\pm}0.8cm$ and $0.9{\pm}0.6cm$, respectively. The vertical and transverse distance between the posterior-inferior margin of the SIJ and the midpoint of the sacral hiatus were $3.4{\pm}0.7cm$ and $3.9{\pm}0.6cm$, respectively. Only the vertical distance between the posterior-inferior margin of the SIJ and PSIS showed significant difference between the male and the female groups (P = 0.0016). Conclusions: The measurements in this study can be used as a reference standards for the blind SIJ block.

• Journal of the Korean Wood Science and Technology
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• v.26 no.2
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• pp.29-37
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• 1998

An image analysis program with the function of measuring various quantitative characteristics in the transverse surface of wood was developed using Delphi 2.0. Data on pore characteristics (conditions for image processing, proportion of pores in relationship to other elements, tangential diameter, area, tangential and radial diameter, x and y coordinates of pore center, and geometric coefficients) were saved in text file format. In addition, the pore area histogram in the tangential and radial directions was saved as a BMP (bitmap) type file. Analyses indicated that quantitative characteristics such as the relative radial distribution of pores in a growth ring, pore tangential area histogram, and proportion of pore in lumen area appear to be useful in separating four diffuse-porous woods and four ring-porous woods on the species level.

• 한국가시화정보학회:학술대회논문집
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• 2004.12a
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• pp.135-140
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• 2004

Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. With our experiences of experimental investigations on nasal airflows in normal and abnormal nasal cavity models, we are going to deal with the topic that may contribute to the diagnosis and treatment of nasal diseases. In this paper, airflows in the normal and artificially deformed models, which simulate surgical treatment, are investigated experimentally by PIV. High-resolution CT data and careful surface rendering of computational model with the help of the ENT doctor provide more sophisticated nasal cavity models. The CBC PIV (Correlation Based Correction PIV) algorithm with window offset is used for PIV flow analysis. Average and RMS distributions in sagittal and coronal sections are obtained for inspiratory and expiratory nasal airflows. Comparisons in nasal airflows for both normal and deformed cases are also appreciated. In case of simulations of surgical operations, velocity and RMS distributions in coronal section changes locally, this may cause some difficulties in physiologic functions of noses and may hurt mucosal surface.