• 한국의학물리학회지:의학물리
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• 제29권2호
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• pp.53-58
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• 2018

This paper evaluates patient-specific quality assurance (PSQA) in the treatment of small and multiple tumors by the CyberKnife system with fixed collimators, using an ion chamber and EBT3 films. We selected 49 patients with single or multiple brain tumors, and the treatment plans include one to four targets with total volumes ranging from 0.12 cc to 3.74 cc. All PSQA deliveries were performed with a stereotactic dose verification phantom. The A16 microchamber (Standard Imaging, WI, USA) and Gafchromic EBT3 film (Ashland ISP Advanced Materials, NJ, USA) were inserted into the phantom to measure the point dose of the target and the dose distribution, respectively. The film was scanned 1 hr after irradiation by a film digitizer scanner and analyzed using RIT software (Radiological Imaging Technology, CO, USA). The acceptance criteria was <5% for the point dose measurement and >90% gamma passing rate using 3%/3 mm and relative dose difference, respectively. The point dose errors between the calculated and measured dose by the ion chamber were in the range of -17.5% to 8.03%. The mean point dose differences for 5 mm, 7.5 mm, and 10 mm fixed cone size was -11.1%, -4.1%, and -1.5%, respectively. The mean gamma passing rates for all cases was 96.1%. Although the maximum dose distribution of multiple targets was not shown in the film, gamma distribution showed that dose verification for multiple tumors can be performed. The use of the microchamber and EBT3 film made it possible to verify the dosimetric and mechanical accuracy of small and multiple targets. In particular, the correction factors should be applied to small fixed collimators less than 10 mm.

• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.79-90
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• 2020

Objective: In the present study, an liquid chromatography/mass spectrometry (LC/MS) metabolomics approach was performed to investigate potential biomarkers of milk production in high- and low-milk-yield dairy cows and to establish correlations among rumen fluid metabolites. Methods: Sixteen lactating dairy cows with similar parity and days in milk were divided into high-yield (HY) and low-yield (LY) groups based on milk yield. On day 21, rumen fluid metabolites were quantified applying LC/MS. Results: The principal component analysis and orthogonal correction partial least squares discriminant analysis showed significantly separated clusters of the ruminal metabolite profiles of HY and LY groups. Compared with HY group, a total of 24 ruminal metabolites were significantly greater in LY group, such as 3-hydroxyanthranilic acid, carboxylic acids, carboxylic acid derivatives (L-isoleucine, L-valine, L-tyrosine, etc.), diazines (uracil, thymine, cytosine), and palmitic acid, while the concentrations of 30 metabolites were dramatically decreased in LY group compared to HY group, included gentisic acid, caprylic acid, and myristic acid. The metabolite enrichment analysis indicated that protein digestion and absorption, ABC transporters and unsaturated fatty acid biosynthesis were significantly different between the two groups. Correlation analysis between the ruminal microbiome and metabolites revealed that certain typical metabolites were exceedingly associated with definite ruminal bacteria; Firmicutes, Actinobacteria, and Synergistetes phyla were highly correlated with most metabolites. Conclusion: These findings revealed that the ruminal metabolite profiles were significantly different between HY and LY groups, and these results may provide novel insights to evaluate biomarkers for a better feed digestion and may reveal the potential mechanism underlying the difference in milk yield in dairy cows.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권2호
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• pp.124-129
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• 2013

Multiple segment osteotomy orthognathic surgery serves to combine the total or segmental maxillary and mandibular correction of the dentofacial deformities with concurrent procedures to provide immediate repositioning to the dento-osseous elements. In addition, splitting the palate may often be necessary to correct a functionally poor relationship of the maxilla to the mandible or the facial skeleton by realigning the maxillary arch. In this case, the discrepancy in a bimaxillary horizontal relationship and the space between the 2nd premolar and 2nd molar was retained after lengthy preoperative orthodontic treatment. However, we could correct these dento-osseous discrepancies immediately by performing midpalatal expansion, anterior segmental osteotomy and symphyseal osteotomy with bimaxillary osteotomies. If the blood supply to each segment segments was maintained and primary closure of the operation site was feasible, multiple segment osteotomy was considered as a very effective technique for treating dentofacial deformities in vertical, transverse, and sagittal dimensions with differential repositioning of all segments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권2호
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• pp.164-171
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• 2000

Purpose : This study was aimed at measuring the changes in the hyoid bone position, tongue position, and pharyngeal airway space in subjects with mandibular setback osteotomies. Methods : Twenty patients were evaluated retrospectively for their changes in pharyngeal airway space, tongue and hyoid bone positions. All patients underwent surgical mandibular setback using bilateral sagittal split osteotomies. The cephalometric analysis was performed preoperatively, and 1 week, 3-6 months, and 1 year postoperatively. Result : The hyoid bone moved inferiorly and posteriorly immediately after surgery, and it returned to the preoperative position during follow-up period. The nasopharyngeal airway space was not significantly changed after surgery. A considerable decrease in the oropharyngeal and hypopharyngeal airway spaces following mandibular setback surgery was found. The upper and lower tongue was posteriorly repositioned immediately after surgery. During follow-up period, the hypopharyngeal airway space and lower tongue posture returned to the preoperative positions, but the oropharyngeal airway space and upper tongue posture were not significantly changed. The position of pogonion remarkably changed to backward immediately after surgery, but slightly anterior advancement was found during follow-up period. Conclusion : Immediately after mandibular setback surgery, the oropharyngeal and hypopharyngeal airway spaces obviously decreased due to posterior and inferior repositions of the tongue and hyoid bone. During follow-up period, lower tongue and hyoid bone returned to the preoperative positions, it was related to advancement of the pogonion in this period. The narrowing of the oropharyngeal airway space and posterior movement of the upper tongue posture were relatively permanent after mandibular setback surgery. We suspected this phenomenon had an influence on maintaining the total volume of oral cavity against mandibular setback.

• 한국통신학회논문지
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• 제37권7A호
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• pp.569-580
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• 2012

본 논문에서는 광범위 고정형 무선 통신 시스템을 위한 개선된 초기 레인징 알고리즘을 제안한다. WiBro 및 통상적인 무선 통신 시스템에서는 송 수신단 간 왕복 지연이 1개의 OFDM (Orthogonal Frequency Division Multiplexing) 심벌 주기 내이므로, 초기 레인징 수행 시 주파수 영역 차동 상관 방식이 일반적으로 사용된다. 그러나, 넓은 셀 범위에서는 최대 시간 지연이 증가하여 기존 기법의 적용이 불가능하며, 성능 개선을 위한 누적 차동 상관 기법의 경우 큰 시간 오프셋 발생 시 추정치의 빈번한 부호 천이로 인해 추정 오차가 발생할 여지가 있다. 따라서, 본 논문에서는 15 km 셀 범위를 고려한 레인징 채널 구조에서 전체 시간 오프셋을 정확히 추정하는 알고리즘을 제안한다. 제안 기법은 추정치 간 부호 비교를 통해 부호 오류를 정정하고, 채널 상관도, 누적횟수 및 정규화 과정의 잡음 감소 효과를 고려하는 가중치를 적용함으로써 추정 정확도를 향상시키며, 심벌 주기의 소수배 시간 오프셋을 보상한 후 첨두치 전력을 비교함으로써 정수 배 시간 오프셋의 추정이 가능하다.

• 한국작물학회지
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• 제46권5호
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• pp.401-406
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• 2001

The applicability of non-destructive near infrared reflectance spectroscopic (NIRS) method was tested to determine the protein and oil contents of intact soybean [Glycine max (L.) Merr.] seeds. A total of 198 soybean calibration samples and 101 validation samples were used for NIRS equation development and validation, respectively. In the developed non-destructive NIRS equation for analysis of protein and oil contents, the most accurate equation was obtained at 2, 8, 6, 1(2nd derivative, 8 nm gap, 6 points smoothing, and 1 point second smoothing) and 2, 1, 20, 10 math treatment conditions with Standard Normal Variate and Detrend (SNVD) scatter correction method and entire spectrum (400-2500 nm) by using Modified Partial Least Squares (MPLS) regression, respectively. Validation of these non-destructive NIRS equations showed very low bias (protein: 0.060%, oil: -0.017%) and standard error of prediction (SEP, protein: 0.568 %, oil : 0.451 %) as well as high coefficient of determination ($R^2$, protein: 0.927, oil: 0.906). Therefore, these non-destructive NIRS equations can be applicable and reliable for determination of protein and oil content of intact soybean seeds, and non-destructive NIRS method could be used as a mass screening technique for selection of high protein and oil soybean in breeding programs.

• 자원환경지질
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• 제32권2호
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• pp.189-201
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• 1999

Paleomagnetic and rock magnetic investigations have been carried out for the Cretaceous Hanyang Group, exposed in the Yongyang Sub-Basins within the Kyeongsang Basin, eastern South Korea. A total of 452 oriented core samples was drilled from 31 sits for the study. The in-situ site mean direction is more dispersed than the mean direction after bedding correction, indicating that the fold test is positive at 95% confidence level. In addition, the stepwise unfolding of the characteristic remanent magfold test is positive at 95% confidence level. In addition, the stepwise unfolding of the characteristic remanent magnetization reveals that a maximum value of k is observed at 90% unfolding. Furthermore, the rock magnetic investigations and electron microscope observations of the representative samples show that the main magnetic carrier of the Hayang Group is the detrital specular hematite of single and pseudo-single domain sizes with negligible contribution of pigmentary hematite grains. These results collectively imply that the ChRM direction is the primary component acquired at the time of the formation of the strata. Provided the primary nature of the ChRM, a magnetostratigraphic correlation between polarities of the studied formation and the Geomagnetic Time Scale indicates that the Hayang Group in the Yongyang Sub-Basin can be correlated to the Cretaceous Long Normal superchron. The paleomagnetic pole position from this study is significantly different from those of the Hayang group in the Euiseong the Milyang sub-Basins. Rather the paleomagnetic pole position of the Hayang Group of the study area is closer to that of the Quaternary period or present time of the Korean Peninsula. It is hypothesized that the study area might be rotated about 25$^{\circ}$ aticlockwise with respect to the Euiseong and Milyang Sub-Basins after the formation of the strata and aquisition of the ChRM, although there is not enough geologic evidence supporting the rotation hypothesis.

• Archives of Plastic Surgery
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• 제35권2호
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• pp.214-218
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• 2008

Purpose: Reconstruction of microtia using costal cartilage graft is commonly used technique nowadays. The chest wall depression at the donor site after the graft, however, has been noticed in many articles. Prevention or correction technique for the depression at the donor site also has been reported and we also have been concerned about the problem. This article is a case report about a new technique preventing chest wall depression after costal cartilage graft. Methods: We selected total 15 microtia patients who visited our clinic, from December 2005 to July 2007. They were 10 male and 5 female patients and the mean age was 11.9 years. The average follow up period was 9.2 months(2 to 15 months). We used 6, 7, and $8^{th}$ costal cartilage for microtia reconstruction. And then we turned over pivot of cartilage resection margin, after bihalving costal cartilage involving about 5-6 cm of $6^{th}$ and $7^{th}$ rib bone. After microtia reconstruction, chest donor sites were evaluated by physical examination and radiography. Results: Postoperative depression at the donor site was much less when the costal cartilage turnover technique was performed. Postoperative physical examination and three dimensional reconstruction CT showed that the rest part of rib bone was turned over and it supported the soft tissue defect during respiration. Conclusion: We expect that the turnover rib bone will not be absorbed after graft, as well as offering mechanical support, compared to the other reports.

• Archives of Plastic Surgery
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• 제36권4호
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• pp.475-480
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• 2009

Purpose: To correct the facial asymmetry and to achieve symmetry and balance, not only the soft tissue restoration of deficits but also creation and facial contour line such as mandible border and angle is important. Micro fat graft has limitation such as high resorption rate and somewhat limited ability to emphasize the rigid bony characteristics of the mandible angle due to its innate soft consistency. We have investigated the advantages of dermal fat graft over micro fat graft to correct asymmetry of the lower face in patients who had undergone mandibular reconstruction or distraction, using comparative analysis. Methods: Total of 12 patients were enrolled in our study: 6 micro fat graft and 6 dermal fat graft. Postoperative results were compared and analyzed at immediate postoperative period and more than 1 year later in each group with photographs, and analysised with image J program. Result: No complications were noted both in the micro fat type and the dermal fat type of procedures such as fat necrosis or micro calcifications. All of the patients who received micro fat graft, however had considerable amount of fat resorption after the procedure which led to two additional fat graft procedures. Although minor contour obliteration due to contracture was seen in patients who had undergone dermal fat graft procedure, no definite resorption was found even after more than one year follow-up. Results of dermal fat graft patients were satisfactory in terms of mandible angle symmetry. Secondary revision was necessary in one case due to overcorrection using dermal fat graft. Conclusion: The dermal fat graft has many advantages over the conventionally more popular micro fat graft to correct asymmetry of the lower face following mandible reconstruction owing to its lower resoption rate, more effective in emphasizing the natural curvilinear anatomical contours of the mandible angle and body and lower complication rates such as fat necrosis or micro calcifications.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.332-336
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• 2017

Background Little is known concerning hair diameter variation within the safe donor area for hair transplantation surgery. Thicker or thinner hair may be needed, depending on the recipient area, hairline design, and the purpose of surgery. Methods Twenty-seven patients (7 men and 20 women; mean age, 28 years; range, 20-47 years) were included in this study. The midoccipital point was used as the reference point on the horizontal plane at the upper border of the helical rim. The target area width was 15 cm (7.5 cm to the right and left of the reference point) and the height was 8 cm (2 cm above and 6 cm below the reference point). The study area was divided horizontally into 3 5-cm sections (A, B, C) and vertically into 4 2-cm sections (1-4), creating a total of 12 zones. Ten anagen hairs were randomly obtained from each zone and their diameters were measured. Results Hair diameter in the 4 vertical sections varied significantly, gradually decreasing from sections 1 (superior) to 4 (inferior) in all 3 horizontal sections (A, B, and C). Conclusions Our results suggest that sections 1 and 2 of the occipital safe donor area would be useful for obtaining thicker hair, such as in procedures to treat male- and female-pattern hair loss, whereas hair from zones 3 and 4 could be useful for transplantation surgery requiring thinner hair, such as eyebrows, eyelashes, and female hairline correction. Our results may be clinically valuable for planning hair transplant surgery and choosing the optimal donor region.