• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.617-632
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• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• Imaging Science in Dentistry
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• v.51 no.2
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• pp.203-208
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• 2021

Ghost cell odontogenic carcinoma (GCOC) is a rare malignant neoplasm characterized by the presence of ghost cells. It is considered to originate from either a calcifying odontogenic cyst(COC) or a dentinogenic ghost cell tumor(DGCT). Its clinical and radiographic characteristics are non-specific, including slow growth, locally aggressive behavior, and eventual metastasis. This case report describes a 43-year-old Thai man with plain radiographs and cone-beam computed tomographic images revealing a unilocular radiolucency with non-corticated borders surrounding an impacted left canine associated with radiopaque foci around the cusp tip. Based on the microscopic findings, the lesion was diagnosed as GCOC. Partial maxillectomy of the right maxilla was performed, and radiotherapy was administered. An obturator was made to support masticatory functions Three years later, the lesion showed complete bone remodeling and no signs of recurrence, and long-term follow-up was done regularly.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.48 no.2
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• pp.125-129
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• 2022

Sialolithiasis is a condition in which the salivary gland excretory duct is obstructed due to the formation of calcareous deposits and is uncommon in children compared to adults. The treatment modalities range from a conservative approach involving hydration to a surgical approach. Though several studies have analyzed the sialolith micromorphology structures, studies on pediatric sialoliths remain scarce. This brief communication aims to describe the sialolith micromorphology to understand the mechanism of mineralization and growth of pediatric sialoliths. A 6-year-old Korean female presented with swelling under her tongue. The intraoral examination revealed a painless yellowish hard mass beneath the tongue near the Wharton's duct which was suspected as a sialolith. After receiving the informed consent, the sialolithotomy was performed under local anesthesia. The obtained stone was analyzed through histopathology and transmission electron microscope examinations to understand the mechanism of mineralization and growth of pediatric sialolith. The micromorphology and growth processes of pediatric sialolith remain undescribed. More comprehensive microscopic studies are needed regarding their distinctive characteristics. By expanding knowledge about sialoliths micromorphology, development of new preventive, diagnostic and patient-tailored treatment methods of pediatric sialolithiasis will be enhanced.

• Corrosion Science and Technology
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• v.20 no.6
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• pp.412-425
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• 2021

Because austenitic stainless steel causes localized corrosion such as pitting and crevice corrosion in environments containing chlorine, corrosion resistance is improved by surface treatment or changes of the alloy element content. Accordingly, research using cyclic potentiodynamic polarization experiment to evaluate the properties of the passivation film of super austenitic stainless steel that improved corrosion resistance is being actively conducted. In this investigation, the electrochemical properties of austenitic stainless steel and super austenitic stainless steel were compared and analyzed through cyclic potentiodynamic polarization experiment with varying temperatures. Repassivation properties were not observed in austenitic stainless steels at all temperature conditions, but super austenitic stainless steels exhibited repassivation behaviors at all temperatures. This is expressed as α values using a relational formula comparing the localized corrosion rate and general corrosion rate. As the α values of UNS S31603 decreased with temperature, the tendency of general corrosion was expected to be higher, and the α value of UNS N08367 increased with increasing temperatures, so it is considered that the tendency of localized corrosion was dominant.

• Journal of Mushroom
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• v.20 no.4
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• pp.249-253
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• 2022

Fungi that infect mushrooms and cause diseases are called mycoparasitic fungi. Understanding the diversity of mycoparasitic fungi in wild mushrooms is important for the mushroom industry, as they can parasitize cultivated mushrooms. However, few studies have been conducted on the diversity of mycoparasitic fungi in wild mushrooms in South Korea. Upon surveying mushroom flora, we found a mycoparasitic fungus and analyzed its strain using molecular phylogeny and morphological examination. The strain was identified as Sepedonium laevigatum, which is an unrecorded species in South Korea. In this study, we described the cultural and microscopic characteristics of this strain of fungus.

• Archives of Plastic Surgery
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• v.50 no.1
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• pp.101-105
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• 2023

Benign cartilaginous tumors, known as chondrogenic tumors, show cartilage components in the microscopic diagnosis. We present two clinical cases with cartilaginous tumors of the toes showing distinctive clinical manifestations. Two juvenile patients visited our outpatient clinic due to tumors with toenail deformities. A 10-year-old girl presented with a palpable mass with a nail deformity on the left third toe. The initial pathology report was soft tissue chondroma until complete resection. Another 15-year-old male patient visited the dermatology department with a toenail deformity and underwent a punch biopsy. The pathology report was fibrosis with myxoid degeneration. Excisional biopsies were performed for both patients. In the operative field, we observed exophytic tumors connected to the distal phalangeal bones. The final pathology reports were subungual osteochondroma on both patients. The specimen exhibited mature bone trabeculae with a focal cartilaginous cap. Benign cartilaginous tumors have a slow, progressive course and do not show significant symptoms. However, tumors in subungual areas are accompanied by toenail deformities and they can cause pain. Their clinical characteristics lead to a delayed diagnosis. Surgeons can be confused between soft tissue and chondrogenic tumors. When they conduct physical examinations, these categories should be considered in the differential diagnosis.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2823-2834
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• 2023

Austenitic stainless steel welds (ASSWs) of nuclear components undergo aging-related degradations caused by high temperature and neutron radiation. Since irradiation leads to the change of material characteristics, relevant quantification is important for long-term operation, but limitations exist. Although ion irradiation is utilized to emulate neutron irradiation, its penetration depth is too shallow to measure bulk properties. In this study, a systematic approach was suggested to estimate mechanical properties of ion irradiated 308 ASSW. First of all, weld specimens were irradiated by 2 MeV proton to 1 and 10 dpa. Microstructure evolutions due to irradiation in δ-ferrite and austenite phases were characterized and micropillar compression tests were performed. In succession, dislocation density based stress-strain (S-S) relationships and quantification models of irradiation defects were adopted to define phases in finite element analyses. Resultant microscopic S-S curves were compared to verify material parameters. Finally, macroscopic behaviors were calculated by multiscale simulations using real microstructure based representative volume element (RVE). Validity of the approach was verified for the unirradiated specimens such that the estimated S-S curves and 0.2% offset yield strengths (YSs) which was 363.14 MPa were in 10% agreement with test. For irradiated specimens, the estimated YS were 917.41 MPa in 9% agreement.

• Mycobiology
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• v.50 no.4
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• pp.203-212
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• 2022

Fungi act as important decomposers in the forest environment. They recycle essential nutrients, promote plant growth through mycorrhizal relationships, and act as food for small animals. Samples of 265 indigenous fungal species were collected from Mudeungsan National Park in 2020. These species were identified based on morphological, molecular, and phylogenetic analyses using the internal transcribed spacer (ITS), nuclear large subunit rRNA (LSU), and RNA polymerase II second largest subunit (rpb2) regions. Subsequently, seven species were identified as unrecorded species in Korea: Cordyceps cicadae, Dentocorticium bicolor, Hymenochaete nanospora, Physisporinus crataegi, Rigidoporus piceicola, Russula raoultii, and Scutellinia crinita. This study reveals their detailed macro- and microscopic morphological characteristics with phylogenetic trees to report them as unrecorded species in Korea.

• Journal of Digestive Cancer Research
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• v.11 no.1
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• pp.49-54
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• 2023

Colorectal cancers often invade adjacent organs; however, direct duodenal invasion is rare. Adenocarcinoma is the most common type of colorectal cancer, but an undifferentiated carcinoma type is unusual. Herein, we present a case of undifferentiated carcinoma of the colon that directly invaded the duodenum and metastasized to distant lymph nodes. An 85-year-old female patient was admitted with a 7-cm-sized colonic mass invading the duodenum, detected by computed tomography. Positron emission tomography revealed fluorodeoxyglucose uptake in the colon, duodenum, and aortocaval lymph nodes. A large encircling mass in the ascending colon and an ulcerated mass in the duodenum were revealed by colonoscopy and esophagogastroduodenoscopy, respectively. Pathologic examinations of the colon and the duodenum revealed nonglandular, diffusely infiltrating atypical round cells, confirming undifferentiated carcinoma of the colon. The histologic type of this tumor was distinguished using immunohistochemical (IHC) markers. Finally, microscopic characteristics and IHC markers aided in identifying the histologic type of colorectal cancer.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.645-652
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• 2023

The aleurone layer in maize is crucial as it contains essential nutrients such as minerals, vitamins, and high-quality proteins. While most of the maize varieties are known to possess a single aleurone layer, several multi-aleurone layer mutants and landraces have been suggested for hierarchical genetic control of aleurone development. Conventional microscopy analysis often involves using immature seeds or sampling only a portion of the kernel sample, and whole kernel section analysis using a microtome is technically difficult and time-consuming. Additionally, the larger size of maize kernels posed challenges for comprehensive cross-sectional analysis compared to other cereal crops. Consequently, this study aimed to develop an efficient method to comprehensively understand the aleurone layer characteristics of the entire cross-section in maize. Through observations of diverse maize genetic resources, we confirmed irregular aleurone layer patterns in those with multiple aleurone layers, and we discovered a landrace having multiple aleurone layers. By selectively identifying genetic resources with multiple aleurone layers, this method may contribute to efficient breeding processes in maize.