• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.563-575
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• 2020

The purpose of this study is to evaluate the activation characteristics that occur in a linear accelerator for container security inspection. In the computer simulation design, first, the targets consisted of a tungsten (Z=74) single material target and a tungsten (Z=74) and copper (Z=29) composite target. Second, the fan beam collimator was composed of a single material of lead (Z=82) and a composite material of tungsten (Z-74) and lead (Z=82) depending on the material. Final, the concrete in the room where the linear accelerator was located contained magnetite type and impurities. In the research method, first, the optical neutron flux was calculated using the MCNP6 code as a F4 Tally for the linear accelerator and structure. Second, the photoneutron flux calculated from the MCNP6 code was applied to FISPACT-II to evaluate the activation product. Final, the decommissioning evaluation was conducted through the specific activity of the activation product. As a result, first, it was the most common in photoneutron targets, followed by a collimator and a concrete 10 cm deep. Second, activation products were produced as by-products of W-181 in tungsten targets and collimator, and Co-60, Ni-63, Cs-134, Eu-152, Eu-154 nuclides in impurity-containing concrete. Final, it was found that the tungsten target satisfies the permissible concentration for self-disposal after 90 days upon decommissioning. These results could be confirmed that the photoneutron yield and degree of activation at 9 MeV energy were insignificant. However, it is thought that W-181 generated from the tungsten target and collimator of the linear accelerator may affect the exposure when disassembled for repair. Therefore, this study presents basic data on the management of activated parts of a linear accelerator for container security inspection. In addition, When decommissioning the linear accelerator for container security inspection, it is expected that it can be used to prove the standard that permissible concentration of self-disposal.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.528-533
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• 2009

In the current study, the mesenchymal stem cells (MSCs) isolated and propagated from the human umbilical cord blood (UCB) were tested for their capabilities of differentiation into chondrocytes in vitro. The mesenchymal progenitor cells (MPCs) collected from UCB were cultured in a low glucose DMEM medium with 10% FBS, L-glutamine and antibiotics. The human MSC colonies were positively stained by PAS reaction. When the immunophenotypes of surface antigens on the MSCs were analyzed by fluorescence-activated cell sorter (FACS) analysis, these cells expressed positively MSC-related antigens of CD 29, CD44, CD 90 and CD105, whereas they did not express antigens of CD14, CD31, CD34, CD45, CD133 and HLA-DR. Following induction these MSCs into chondrocytes in the chondrogenic differentiation medium for 3 weeks or more, the cells were stained positively with safranin O. We clearly confirmed that human MSCs were successfully differentiated into chondrocytes by RT-PCR and immunofluorescent stain of type-II collagen protein. These data also indicate that the isolation, proliferation and differentiation of the hUCB-derived MSCs in vitro can be used for elucidating the mechanisms involved in chondrogenesis. Moreover this differentiation technique can be applied to developing cell-based tissue regeneration or repair damaged tissues.

• Journal of the Korean Arthroscopy Society
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• v.10 no.1
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• pp.77-82
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• 2006

Purpose: The purpose of this study was to analyze the clinical results of symptomatic lateral discoid meniscus found in adults over 40 years old. Materials & Methods: From March 1994 to March 2004, 53 cases treated for lateral discoid meniscus in 48 patients aged over 40 years with the mean age $48.4(40{\sim}62)$ who were followed up more than 1 year, were analyzed by physical findings, simple X-ray, MRI and arthroscopic exam. Results: Most of the cases (42 cases, 79.2%) had symptoms for less than 1 year duration. 26 cases(49.1 %) out of 53 had trauma history. Simple radiologic evaluation showed that lateral condylar abnormality such as the flattening of lateral femoral condyle, marginal osteophytes, and subchondral sclerosis was seen in 37cases(69.8%). Also medial condyle showed degenerative changes in 16 cases (30.2%). Tear of discoid meniscus in 45 cases(84.9%) were examined by arthroscope and tear was not detected in 8 cases(15.1%). Type of tear was complex(18 cases), longitudinal(12 cases), horizontal(11 cases) and transverse(4 cases). Concomitant medial meniscal rupture was found in 7 cases(13.2%). The simple procedure done was reshaping(46 cases), subtotal resection(5 cases), total resection(1 case) and meniscal repair after reshaping in 6 cases, and arthroplasty was performed after arthroscopic examination in 1 case. Conclusion: Onset of symptom in adult lateral discoid meniscus is usually traumatic in origin. Most cases showed radiologic abnormality such as degenerative change in lateral condyles as well as medial condyles and the results of preservative surgical treatment was the most preferred option in most patients.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.4
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• pp.104-113
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• 2012

This study aimed to find out the improvement plan through analyzing the perception of the expert group engaged in landscape architectural construction and to focus on analyzing the expert groups' experience on Landscape Construction Defects (LCD), defect liability, warranty period, and implementation of the defect liability. The results are as follows: 1. Regarding the experience on the LCD, landscape construction contractors were an awareness of the LCD issue at a serious level, while public-sector clients recognize moderately the LCD issue; and on the first priority in defect implementation, landscape construction contractors considered repair cost while public-sector clients value the identifying causes of defects. 2. In disagreement on the defect liability, landscape construction contractors attributed it to client's lack of responsibility for maintenance while public-sector clients ascribed it to the absence of dealing a criteria with LCD, and regarding the appropriate defect implementation, public-sector clients preferred the following objective by dealing the criteria with LCD while landscape construction contractors advocates by sharing the responsibilities for dealing with LCD based on the identified causes of construction defects. 3. Regarding the warranty period, the public-sector clients considered the 2-year warranty period as appropriate while landscape construction contractors considered it comparatively long, and concerning the commencement of defect warranty period, the public-sector clients viewed it as it should commence to cover the overall completion of the construction while landscape construction contractors perceived it to start on the completion of each work. 4. As for the improvement of the defect implementation system, public-sector clients considered it necessary to establish the objective dealing the criteria with LCD while landscape construction contractors viewed the legislation of maintenance duty. Also, with regard to the important value in establishing and dealing the criteria with LCD, public-sector clients pointed out the objective of the criteria for determining the defects per work type while landscape construction contractors suggested client (user)'s maintenance duty. Because of research, because the system in dealing with LCD is an absence of LCD management agency and dealing the criteria with LCD, it is needed to establish an LCD management agency and make the system in dealing with LCD.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6403-6409
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• 2013

Purpose: Biallelic germline variants of the 8-hydroxyguanine (8-OG) repair gene MYH have been associated with colorectal neoplasms that display somatic $G:C{\rightarrow}T:A$ transversions. However, the effect of single germline variants has not been widely studied, prompting the present investigation of monoallelic MYH variants and susceptibility to sporadic colorectal cancer (CRC) in a Chinese population. Patients and Methods: Between January 2006 and December 2012, 400 cases of sporadic CRC and 600 age- and sex-matched normal blood donors were screened randomly for 7 potentially pathogenic germline MYH exons using genetic testing technology. Variants of heterozygosity at the MYH locus were assessed in both sporadic cancer patients and healthy controls. Univariate and multivariate analyses were performed to determine risk factors for cancer onset. Results: Five monoallelic single nucleotide polymorphisms (SNPs) were identified in the 7 exon regions of MYH, which were detected in 75 (18.75%) of 400 CRC patients as well as 42 (7%) of 600 normal controls. The region of exon 1 proved to be a linked polymorphic region for the first time, a triple linked variant including exon 1-316 $G{\rightarrow}A$, exon 1-292 $G{\rightarrow}A$ and intron 1+11 $C{\rightarrow}T$, being identified in 13 CRC patients and 2 normal blood donors. A variant of base replacement, intron 10-2 $A{\rightarrow}G$, was identified in the exon 10 region in 21 cases and 7 controls, while a similar type of variant in the exon 13 region, intron 13+12 $C{\rightarrow}T$, was identified in 8 cases and 6 controls. Not the only but a newly missense variant in the present study, p. V463E (Exon 14+74 $T{\rightarrow}A$), was identified in exon 14 in 6 patients and 1 normal control. In exon 16, nt. 1678-80 del GTT with loss of heterozygosity (LOH) was identified in 27 CRC cases and 26 controls. There was no Y165C in exon 7 or G382D in exon 14, the hot-spot variants which have been reported most frequently in Caucasian studies. After univariate analysis and multivariate analysis, the linked variant in exon 1 region (p=0.002), intron 10-2 $A{\rightarrow}G$ (p=0.004) and p. V463E (p=0.036) in the MYH gene were selected as 3 independent risk factors for CRC. Conclusions: According to these results, the linked variant in Exon 1 region, Intron 10-2 $A{\rightarrow}G$ of base replacement and p. V463E of missense variant, the 3 heterozygosity variants of MYH gene in a Chinese population, may relate to the susceptibility to sporadic CRC. Lack of the hot-spot variants of Caucasians in the present study may due to the ethnic difference in MYH gene.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.99-105
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• 2006

Background: Interrupted aortic arch is a rare congenital heart anomaly which still shows high surgical mortality. In this study, we investigated the causes of and the risk factors for mortality to improve the surgical outcomes for this difficult disease entity. Material and Method: From 1984 to 2004, 42 patients diagnosed as IAA were reviewed retrospectively. Age, body weight at operation, preoperative diagnosis, preoperative PGE1 requirement, type of interrupted aortic arch, degree of left ventricular outflow stenosis, CPB time, and ACC time were the possible risk factors for mortality. Result: There were .14 hospital deaths. Preoperative use of PGE1, need for circulartory assist and aortic cross clamp time proved to be positive risk factors for mortality on univariate analysis. Preoperative left ventricular outflow stenosis was considered a risk factor for mortality but it did not show statistical significance (p-value=0.61). Causes of death included hypoxia due to pulmonary banding, left ventricular outtract stenosis, infection, mitral valve regurgitation, long cardiopulmonary bypass time and failure of coronary transfer failure in TGA patients. Conclusion: In this study, we demonstrated that surgical mortality is still high due to the risk factors including preoperative status and long operative time. However preoperative subaortic dimension was not related statistically to operative death statistically. Adequate preoperative management and short operation time are mandatory for better survival outcome.

• Journal of Chest Surgery
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• v.34 no.8
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• pp.597-603
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• 2001

Background: The purpose of writing this article is to get better clinical results and further clinical improvement based on subject to 110 cases of cardiac surgery which were performed and clinically analyzed. Material and Method: Since January 1995, the patent ductus arteriosus surgery had started in our hospital. In February 1999, an open heart surgery had started and up to September 2000, total of 110 cases were performed as of double ligation of patent ductus arteriosus(10 cases) and open heart surgery(100 cases). Result: Among the patients, Korean-Chines was 74(67.3%) and Han-Chinese was 35(31.8%). Congenital heart disease was 95 cases and acquired valvular heart disease was 15 cases. 83 cases of acyanotic congenital heart disease consisted of ventricular septal defect(VSD) with associated anomaly(45 cases), atrial septal defect(ASD) with associated anomaly(20 cases), patent ductus arteriosus(PDA) with associated anomaly(11 cases), cogenital aortic stenosis(5 cases), double chamber right ventrical(1 case) and Ebstein's anomaly(1 case). Among the 12 cases of cyanotic congenital heart disease, 11 cases of tetralogy of Fallot underwent total correction. Among the 15 cases of acquired valvular heart disease, valvular replacement(7 cases), double valve replacement (3 cases), mitral valve replacement(3 cases) and aortic valve replacement(1 case) were performed. And 8 cases of valvuloplasty were performed by using of commissurotomy, chordal plasty, plasty of papillary muscle, ring type annuloplasty, repair of leaflet. Conclusion: on cogenital heart disease, short term results of surgery for acyanotic cogenital heart disease was good. Among the cyanotic congenital heart disease, tetralogy of Fallot showed a little difference of recovery according to the surgery method so that further follow up observation was needed for long term result. On acquired valvular heart disease, especially, in terms of short term result of valvuloplasty, was relatively good, but further follow up observation was also needed for long term result. There wasn's any operative mortality.

• Journal of Environmental Impact Assessment
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• v.28 no.4
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• pp.387-399
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• 2019

This research aimed to prepare the classification of the damage types and the damage rating system of noise barriers for expressway noise barriers and to develop deterioration evaluation method of noise barriers by reflecting them. The noise barrier consists of soundproof panels, foundations and posts and the soundproof panels with 10 different types of materials are used in a single or mixed form.In this paper, damage of soundproof panel shows a single or composite damage, and thus a evaluation model of deterioration has been developed for noise barriers that can reflect the characteristic of noise barriers. Materials used mainly for soundproof walls were divided into material types for metal, plastic, timber, transparent and concrete. And damage types for noise barrier were classified into corrosion, discoloration, deformation, spalling and dislocation and damage types were subdivided according to the noise barrier's components and materials. Damage rating was divided into good, minor, normal and severe for each major part of noise barrier to assess damage rating of soundproof panel, foundation and post. The deterioration degree of noise barrier was evaluated comprehensively by using the deterioration evaluation method of whole noise barrier using weighted average. Deterioration evaluation method that can be systematically assessed has been developed for noise barrier using single or mixed soundproof panel and noise barrier with single or complex damage types. Through such an evaluation system, it is deemed that the deterioration status of noise barrier installed can be systematically understood and utilized for efficient maintenance planning and implementation for repair and improvement of noise barriers.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.212-228
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• 2013

Stone cultural heritages are repaired by the use of metal stiffeners. The problem is that this type of repair has been based on the experience of workers without specific guidelines and has caused various problems. This is to suggest the structural reinforcement and behavioral characteristics of metal rods to minimize the secondary damage of materials and have the specimens tested and verified to establish the guidelines on how to insert metal stiffeners. When only epoxy resin is applied to the cut surface, only 70% of the properties of the parent material are regenerated and it is required to structurally reinforce the metal stiffener for the remaining 30%. The metal rod is under the structural behavior after the brittle failure of stone material and the structural behavior does not occur when the metal stiffener is below 0.251%. When it accounts for over 0.5%, it achieves structural reinforcement, but causes secondary damage of parent materials. The appropriate ratio of metal stiffener for the stone material with the strength of $1,500kgf/cm^2$, therefore, should be between 0.283% and 0.377% of the cross section of attached surface to achieve reversible fracture and ductility behavior. In addition, it is more effective to position the stiffeners at close intervals to achieve the peak stress of metal rod against bending load and inserting the stiffener into the upper secions is not structurally supportive, but would rather cause damage of the parent material. Thus, most stiffeners should be inserted into the lower part and some into the central part to work as a stable tensile material under the load stress. The dispersion effect of metal rods was influenced by the area of reinforcing rods and unrelated to their diameter. However, it ensures stability under the load stress to increase the number of stiffeners considering the cross section adhered when working on large-scale structures. The development length is engineered based upon the diameter of stiffener using the following formula: $l_d=\frac{a_tf_y}{u{\Sigma}_0}$. Also, helically-threaded reinforcing rods should be used to perform the behaviors as a structural material.

• Korean Journal of Heritage: History & Science
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• v.38
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• pp.179-222
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• 2005

Studies prosecuted on relics in those 17 bronze workshops that have been thus far excavated show that these workshops may be roughly classified into a royal workshop, a state-operated workshop and a private workshop depending upon by whom they were operated. Workshops in the Gyeongju area developed from a small royal handicraft manufacturing to a large state-operated handicraft manufacturing scale, and then later on gradually changed to a private handicraft manufacturing industry. The royal bronze workshops were operated in a small scale, as shown from the relics excavated at Wolseong(月城), Imhaejeonji(Anapji:雁鴨池) and their neighborhood places around Hwangnam_dong(皇南洞). The state-operated bronze workshops are concentrated upon one point around Dongcheon-dong(東川洞), Gyeongju city. On the other hand, in the state-operated workshop stage, a broad street was built by a workshop, which is presumed to aim to thoroughly transport materials needed for the workshop. And the point that wastes from bronze workshops were used for road repairs indicates that road repair works were carried at the bronze workshops near the road. The private workshop as a new type of workshop was operated by the aristocracy. For that purpose, craftsmen belonging to state-operated workshops or individual artisans were absorbed into the aristocracy-operated workshops. These types of workshops were pervaded throughout the city. When private workshops came to emerge in the houses of the aristocracy, the operating subjects of workshops began to change from state-operated to private workshops. Temple workshops were located at a Buddhist temple within the Court and directly produced things needed for the court, including bronze foundries. As aforementioned, through the presence of bronze workshops operated in the Silla Court, we can identify the relationships between their technical level and trading areas and among their origin, supply and demand sources, along with phases of social life in those days.