• Progress in Superconductivity and Cryogenics
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• v.11 no.4
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• pp.20-24
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• 2009

YBCO coated conductors (CC) on the $CeO_2$-buffered IBAD-MgO template were fabricated by metal-organic deposition (MOD) Process with Ba-trifluoroacetate and fluorine-free Y and Cu precursor materials. The precursor solution was coated on $CeO_2$-buffered IBAD MgO templates using the multiple dip-coating method, decomposed into inorganic precursors by pyrolysis up to $400^{\circ}C$ within 3 h, and finally fired at $740{\sim}800^{\circ}C$ in a reduced oxygen atmosphere. Microstructure, texture, and superconducting properties of YBCO films were found highly sensitive to both the firing temperature and time. The high critical current density ($J_C$) of $1.15\;MA/cm^2$ at 77.3K in the self-field could be obtained from $1\;{\mu}m$ thick YBCO CC, fired at $740^{\circ}C$ for 3.5 h, implying that high performance YBCO CC is producible on IBAD MgO template. Further enhancement of $J_C$ values is expected by improving the in-plane texture of $CeO_2$-buffer layer and avoiding the metal substrate contamination.

• Asia Pacific Journal of Corpus Research
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• v.4 no.1
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• pp.61-71
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• 2023

This study examines the effects of data-driven learning (DDL)-an approach employing corpora for inductive language pattern learning-on error identification in second language (L2) writing. The data consists of error identification instances from fifty-five participants, compared across different reference materials: the Corpus of Contemporary American English (COCA), dictionaries, and no use of reference materials. There are three significant findings. First, the use of COCA effectively identified collocational and form-related errors due to inductive inference drawn from multiple example sentences. Secondly, dictionaries were beneficial for identifying lexical errors, where providing meaning information was helpful. Finally, the participants often employed a strategic approach, identifying many simple errors without reference materials. However, while maximizing error identification, this strategy also led to mislabeling correct expressions as errors. The author has concluded that the strategic selection of reference materials can significantly enhance the effectiveness of error identification in L2 writing. The use of a corpus offers advantages such as easy access to target phrases and frequency information-features especially useful given that most errors were collocational and form-related. The findings suggest that teachers should guide learners to effectively use appropriate reference materials to identify errors based on error types.

• Journal of Powder Materials
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• v.30 no.6
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• pp.516-520
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• 2023

Highly safe lithium-ion batteries (LIBs) are required for large-scale applications such as electrical vehicles and energy storage systems. A highly stable cathode is essential for the development of safe LIBs. LiFePO₄ is one of the most stable cathodes because of its stable structure and strong bonding between P and O. However, it has a lower energy density than lithium transition metal oxides. To investigate the high energy density of phosphate materials, vanadium phosphates were investigated. Vanadium enables multiple redox reactions as well as high redox potentials. LiVPO₄O has two redox reactions (V⁵⁺/V⁴⁺/V³⁺) but low electrochemical activity. In this study, LiVPO₄O is doped with fluorine to improve its electrochemical activity and increase its operational redox potential. With increasing fluorine content in LiVPO₄O_1-xF_x, the local vanadium structure changed as the vanadium oxidation state changed. In addition, the operating potential increased with increasing fluorine content. Thus, it was confirmed that fluorine doping leads to a strong inductive effect and high operating voltage, which helps improve the energy density of the cathode materials.

• Composites Research
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• v.13 no.3
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• pp.9-20
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• 2000

Free vibration characteristics of a cantilevered laminated composite beam with multiple non-propagating transverse open cracks are investigated. In the present analysis a special ply-angle distribution referred to as asymmetric stiffness configuration inducing the elastic coupling between chord-wise bending and extension is considered. The multiple open cracks are modelled as equivalent rotational springs whose spring constants are calculated based on the fracture mechanics of composite material structures. Governing equations of a composite beam with open cracks are derived via Hamilton's Principle and Timoshenko beam theory encompassing transverse shear and rotary inertia effect is adopted. The effects of various parameters such as the ply angle, fiber volume fraction, crack numbers, crack positions and crack depthes on the free vibration characteristics of the beam with multiple cracks are highlighted. The numerical results show that the existence of the multiple cracks in an anisotropic composite beam affects the free vibration characteristics in a more complex fashion compared with the beam with a single crack.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.66-73
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• 2008

Purpose: To report the clinical results of tibio-talo-calcaneal arthrodesis fixed with multiple cannulated screws for the cases of painful ankle and hindfoot arthropathy regardless of any deformity or instability. Materials and Methods: A retrospective analysis was performed upon 10 patients that underwent tibio-talo-calcaneal arthrodesis from October 1999 to May 2006. There were 4 males and 6 females, with an average age of 63 years (43-70). The etioloty of arthrodesis included 5 osteoarthritis, 2 Charcot joints, 1 rheumatoid arthritis, 1 Tbc arthritis and 1 residual poliomyelitis. Chief complaints were pain in 9 cases and instability in 1 case. Three patients had combined severe varus deformity. Tibio-talo-calcaneal arthrodesis using multiple cannulated screws was performed by transfibular approach for all cases and short leg cast was applied for 12 weeks postoperatively. Results: The average follow-up period was 16.5 months (12-26 months). VAS pain score was average 8.2 (7-10) and modified AOFAS score was average 25 (8-40, total 86) preoperatively. At final follow-up, VAS score was average 1.0 (0-3) and AOFAS score improved to average 66 (58-75). There were 4 complications: 2 nonunion, 1 tibia stress fracture and 1 malunion. Seven of 8 patients were satisfied with the results at final follow-up. Conclusion: Fixation with multiple cannulated screws for tibio-talo-calcaneal arthrodesis through transfibular approach is a recommendable surgical option.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4543-4548
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• 2015

Background: To investigate the effects of ASMase mediated endothelial cell apoptosis in multiple hypofractionated irradiations in CT26 tumor bearing mice. Materials and Methods: Thirty-five CT26 tumor bearing mice were subjected to single ionizing radiation (IR) of 0, 3, 6, 9, 12, 15, 18 Gy. Eight hours after IR, the mice were sacrificed and tumor tissues were used for CD31 immunohistochemistry staining, TUNEL and CD31 double staining, ASMase activity assay. Then 6 and 12 Gy were chosen for multiple hypofractionated IR experiments according to the above results. Each time after IR, 5 mice were sacrificed and assayed as above. Results: The ASMase activities were increased significantly after a single IR of 12 Gy or higher which was accompanied with remarkable increased endothelial cell apoptosis and decreased MVD. For 6 Gy which was not high enough to trigger ASMase activation, after 2 or more times of IR, the ASMase activities were significantly increased accompanied with remarkable increased endothelial cell apoptosis and decreased MVD. While for 12 Gy, after 2 or more times of IR, the ASMase activities and endothelial cell apoptosis rates were maintained without remarkable increase; however, the MVD was significantly decreased. What's more, the cancer cell apoptosis rates were significantly increased after multiple IR for both 6 Gy and 12 Gy. Conclusions: ASMase mediated endothelial cell apoptosis may play an important role in the process of multiple hypofractionated IR for CT26 colorectal carcinoma.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3605-3610
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• 2016

Background: Histone acetylation in chromatin structures plays a key role in regulation of gene transcription and is strictly controlled by histone acetyltransferase (HAT) and deacetylase (HDAC) activities. HDAC deregulation has been reported in several cancers. Materials and Methods: The expression of 10 HDACs (including HDAC class I and II) was studied by quantitative reverse transcription-PCR (qRT-PCR) in a cohort of mesenchymal stem cells (MM-MSCs) from 10 multiple myeloma patients with a median age 60y. The results were compared with those obtained for normal donors. Then, a coculture system was performed between MM-MSCs and u266 cell line, in the presence or absence of sodium butyrate (NaBT), to understand the effects of HDAC inhibitors (HDACi) in MM-MSCs on multiple myeloma cases. Also, the interleukin-6 (IL-6) and vascular endothelial growth factor (VEGFA) gene expression level and apoptotic effects were investigated in MM-MSCs patients and control group following NaBT treatment. Results: The results indicated that upregulated (HDACs) and downregulated (IL6 and VEGFA) genes were differentially expressed in the MM-MSCs derived from patients with multiple myeloma and ND-MSCs from normal donors. Comparison of the MM-MSCs and ND-MSCs also showed distinct HDACs expression patterns. For the first time to our knowledge, a significant increase of apoptosis was observed in coculture with MM-MSCs treated with NaBT. Conclusions: The obtained findings elucidate a complex set of actions in MSCs in response to HDAC inhibitors, which may be responsible for anticancer effects. Also, the data support the idea that MSCs are new therapeutic targets as a potential effective strategy for MM.

• Safety and Health at Work
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• v.11 no.1
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• pp.50-60
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• 2020

Background: The relationship between risk factors and likelihood of occupational injury has been studied. However, what has been published has only provided a limited explanation of why some of the employees working in the same environment as other employees suffered a single-injury event, while other employees experienced multiple-injury events. This article reports on an investigation of whether artisanal and small-scale miners in Migori County of Kenya are susceptible to a single-injury or multiple-injury incidences, and if so, what underpinning parameters explain the differences between the single incident injured and the multiple incident injured group. Mine management commitment to safety in artisanal and small-scale mining (ASM) operations is also considered. Materials and methods: The research objectives were achieved by surveying 162 uninjured and 74 injured miners. A structured, closed-end questionnaire was administered to participants after the stratification of the study population and systematic selection of the representative samples. Results: The results showed that most injured miners suffer a single-injury incident rather than experiencing multiple-injury events, and laceration (28.40%) was the common injury suffered by the miners. The analysis showed that the risk factors for the single incident injured group were not similar to those in the multiple incident injured group. The research also found mine workers have low opinion about mine management/owners commitment to safety. Conclusion: The study concluded that mine management and miners need to be educated and sensitized on the dangers of this operation. Provision of safety gears and positive safety culture must be a top priority for management.

• The Journal of Korean Association of Computer Education
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• v.7 no.4
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• pp.103-110
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• 2004

As the importance of learner-centered ICT education is emphasized, school education should move toward the direction of respecting individual learners' capability rather than fitting learners into a fixed frame. Such a view finds its theoretical ground in Gardner's multiple intelligences theory. Thus ICT literacy education in elementary school also needs to consider individual student's abilities and talents based on their multiple intelligences and apply appropriate education programs and teaching methods. In order to provide basic materials for this, the present study examined the correlation between children's academic achievement in ICT literacy education and their multiple intelligences and inquired into which intelligences are factors determining achievement in ICT literacy education. According to the results. logical-mathematical intelligence is in a significant correlation with academic achievement in ICT literacy education. and logical-mathematical intelligence and linguistic intelligence are the most influential factors on academic achievement in ICT literacy education.

• Journal of Gastric Cancer
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• v.17 no.2
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• pp.154-161
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• 2017

Purpose: This study aimed to investigate the correlation between multiple early gastric cancer (MEGC) and multiple primary malignancies during the follow-up of patients with gastrectomy. Materials and Methods: The number of primary tumors detected in other organs after gastrectomy for early gastric cancer (EGC) has been increasing because of improved survival and surveillance programs. A total of 3,129 patients underwent radical gastrectomy for treatment of EGC at Samsung Medical Center from January 2000 to December 2005. Of these, 3,057 patients were selected and their medical records were retrospectively analyzed. Results: Among the 3,057 patients, 148 (4.8%) had MEGC, 84.5% were male, 57.4% were over 60 years old, 42.6% had a macroscopic type EGC IIb main lesion, and 68.9% had well-differentiated tumors with a significantly high incidence of MEGC. There were no differences between patients with solitary early gastric cancer (SEGC) and those with MEGC with regard to overall survival or recurrence-free survival, but MEGC was an independent risk factor for metachronous primary malignancies in other organs (P=0.004, hazard ratio [HR]=2.444). Conclusions: MEGC is not a risk factor for poor prognosis after curative gastrectomy, but it is a risk factor for metachronous primary malignancies in other organs during postoperative follow-up; therefore, careful surveillance is needed.