• International journal of steel structures
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• v.18 no.5
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• pp.1666-1683
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• 2018

To explore seismic behavior of blind bolted concrete-filled steel tube (CFST) frames infilled with precast sandwich composite wall panels (SCWPs), a series tests of blind bolted square CFST frames with precast SCWPs under lateral low-cyclic loading were conducted. The influence of the type of wall concrete, wall-to-frame connection and steel brace setting, etc. on the hysteretic curves and failure modes of the type of composite structure was investigated. The seismic behavior of the blind bolted CFST frames with precast SCWPs was evaluated in terms of lateral load-displacement relation curves, strength and stiffness degradation, crack patterns of SCWPs, energy dissipation capacity and ductility. Then, a finite element (FE) analysis modeling using ABAQUS software was developed in considering the nonlinear material properties and complex components interaction. Comparison indicated that the FE analytical results coincided well with the test results. Both the experimental and numerical results indicated that setting the external precast SCWPs could heighten the load carrying capacities and rigidities of the blind bolted CFST frames by using reasonable connectors between frame and SCWPs. These experimental studies and FE analysis would enable improvement in the practical design of the SCWPs in fabricated CFST structure buildings.

• Steel and Composite Structures
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• v.38 no.6
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• pp.617-635
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• 2021

This paper numerically investigated the behavior of built-up square concrete-filled steel tubular (CFST) columns under combined preload and axial compression. The finite element (FE) models of target columns were verified in terms of failure mode, axial load-deformation curve and ultimate strength. A full-range analysis on the axial load-deformation response as well as the interaction behavior was conducted to reveal the composite mechanism. The parametric study was performed to investigate the influences of material strengths and geometric sizes. Subsequently, influence of construction preload on the full-range behavior and confinement effect was investigated. Numerical results indicate that the axial load-deformation curve can be divided into four working stages where the contact pressure of curling rib arc gradually disappears as the steel tube buckles; increasing width-to-thickness (B/t) ratio can enhance the strength enhancement index (e.g., an increment of 1.88% from B/t=40 to B/t=100), though ultimate strength and ductility are decreased; stiffener length and lip inclination angle display a slight influence on strength enhancement index and ductility; construction preload can degrade the plastic deformation capacity and postpone the origin appearance of contact pressure, thus making a decrease of 14.81%~27.23% in ductility. Finally, a revised equation for determining strain εscy corresponding to ultimate strength was proposed to evaluate the plastic deformation capacity of built-up square CFST columns.

• Steel and Composite Structures
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• v.45 no.5
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• pp.749-766
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• 2022

This paper investigates the seismic performance of exposed RCFST column-base joints, in which the high-strength steel bars (USD 685) are set through the column and reinforced concrete foundation without any base plate and anchor bolts. Three specimens with different axial force ratios (n = 0, 0.25, and 0.5) were tested under cyclic loadings. Finite element analysis (FEA) models were validated in the basic indexes and failure mode. The hysteresis behavior of the exposed RCFST column-base joints was studied by the parametrical analysis including six parameters: width of column (D), width-thickness ratio (D/t), axial force ratio (n), shear-span ratio (L/D), steel tube strength (f_y) and concrete strength (f_c). The bending moment of the exposed RCFST column-base joint increased with D, f_y and f_c. But the D/t and L/D play a little effect on the bending capacity of the new column-base joint. Finally, the calculation formula is proposed to assess the bending moment capacities, and the accuracy and stability of the formula are verified.

• Restorative Dentistry and Endodontics
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• v.36 no.1
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• pp.50-58
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• 2011

Objectives: The purpose of this study was to compare the microshear bond strength (uSBS) of two totaletch and four self-etch adhesive systems and a flowable resin to enamel. Materials and Methods: Enamels of sixty human molars were used. They were divided into one of six equal groups (n = 10) by adhesives used; OS group (One-Step Plus), SB group (Single Bond), CE group (Clearfil SE Bond), TY group (Tyrian SPE/One-Step Plus), AP group (Adper Prompt L-Pop) and GB group (G-Bond). After enamel surfaces were treated with six adhesive systems, a flowable composite resin (Filek Z 350) was bonded to enamel surface using Tygon tubes. the bonded specimens were subjected to uSBS testing and the failure modes of each group were observed under FE-SEM. Results: 1. The uSBS of SB group was statistically higher than that of all other groups, and the uSBS of OS, SE and AP group was statistically higher than that of TY and GB group (p < 0.05). 2. The uSBS for TY group was statistically higher than that for GB group (p < 0.05). 3. Adhesive failures in TY and GB group and mixed failures in SB group and SE group were often analysed. One cohesive failure was observed in OS, SB, SE and AP group, respectively. Conclusions: Although adhesives using the same step were applied the enamel surface, the uSBS of a flowable resin to enamel was different.

• Journal of Korean Society of Steel Construction
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• v.17 no.3 s.76
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• pp.325-335
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• 2005

This study tackles the development of an improved detail of partially restrained CFT square column-to-beam connection and the evaluation of its mechanical behavior under monotonic loading. The connection is designed to strengthen shearing capacity at the bottom of the connection due to the ultimate behavior of PR-CC by its detail of the bottom connection and simplify the fabrication process. The suggested connection is the welded bottom beam flange connection(M-2) and is compared with the existing PR-CC of bolted seat angle connection(M-1). Two specimens were fabricated in actual size and tested under monotonic loading. Based on the test results, the welded bottom beam flange connection exhibited about 85% of the stiffness of steel beam. It was similar to the bolted seat angle connection and behaved as PR-CC. The specimen of the supposed connection type failed at the shear connection of web but was similar to the bolted seat angle connection until the failure. It obtained sufficient stiffness and capacity through the reinforcingsteel and the capacity and deformational ability equivalent to the full-plastic moment through the anchor inside the steel tube at the web connection. So, it can be said that the suggested connection exhibits sufficient ductile behavior.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.235-242
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• 2017

Marsupialization and decompression constitute a well-established procedure for treating cavitary bone lesions of the jaw. The technique can be a primary treatment option, especially for pediatric patients with large cysts or lesions involving vital anatomical structures, such as a developing tooth germ. In this procedure, a decompression stent, such as a customized acrylic obturator or space-maintaining appliance, silicone tube, or nasal cannula, is inserted to maintain the patency of the cyst. However, this may cause clinical problems, such as irritation or trauma to the adjacent tissues, as well as discomfort to the patient, or failure of the stent due to cyst shrinkage. It can also be a reason for patient noncompliance. In the cases described here, a minimally invasive marsupialization technique using a metal tube made from a 16-gauge needle was used for odontogenic cysts in pediatric patients associated with unerupted teeth. Through this method, the lesions were removed, with patient cooperation, and the cyst-associated teeth erupted spontaneously.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.253-275
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• 1994

Many flowering plants possess genetically controlled self -incompatibility (SI) system that prevents inbreeding and promotes outcrosses. SI is usually controlled by a single, multiallelic S-locus. In gametophytically controlled system, SI results when the S-allele of the pollen is matched by one of the two S-alleles in the style, while in the sporophytic system self-incompatible reaction occurs by the interaction between the pistil genotype and genotype of, not the pollen, but the pollen parent In the former system the self-incompatible phenotype of pollen is determined by the haploid genome of the pollen itself but in the latter the pollen phenotype is governed by the genotype of the pollen parent along with the occurrence of either to-dominant or dominant/recessive allelic interactions. In the sporophytic type the inhibition reaction occurs within minutes following pollen-stigma contact, the incompatible pollen grains usually failing to germinate, whereas in gametophytic system pollen tube inhibition takes place during growth in the transmitting tissue of the style. Recognition and rejection of self pollen are the result of interaction between the S-locus protein in the pistil and the pollen protein. In the gametophytic SI the S-associated glycoprotein which is similar to the fungal ribonuclease in structure and function are localized at the intercellular matrix in the transmitting tissue of the style, with the highest concentration in the collar of the stigma, while in the sporophytic SI deposit of abundant S-locus specific glycoprotein (SLSG).is detected in the cell wall of stigmatic papillae of the open flowers. In the gametophytic system S-gene is expressed mostly at the stigmatic collar the upper third of the style length and in the pollen after meiosis. On the other hand, in the sporophytic SI S-glycoprotein gene is expressed in the papillar cells of the stigma as well as in e sporophytic tape is cells of anther wall. Recognition and rejection of self pollen in the gametophytic type is the reaction between the ribonuclease in the transmitting tissue of the style and the protein in the cytoplasm of pollen tube, whereas in the sporophytic system the inhibition of selfed pollen is caused by the interaction between the Sycoprotein in the wall of stigmatic papillar cell and the tapetum-origin protein deposited on the outer wall of the pollen grain. The claim that the S-allele-associated proteins are involved in recognition and rejection of self pollen has been made merely based on indirect evidence. Recently it has been verified that inhibition of synthesis of S$_3$ protein in Petunia inflata plants of S$_2$S$_3$ genotype by the antisense S$_3$ gene resulted in failure of the transgenic plant to reject S$_3$ pollen and that expression of the transgenic encoding S$_3$ protein in the S$_1$S$_2$ genotype confers on the transgenic plant the ability to reject S$_3$ pollen. These finding Provide direct evidence that S-proteins control the s elf-incompatibility behavior of the pistil.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.1
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• pp.44-52
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• 2023

Objective: The DNA integrity of spermatozoa that attach to fallopian tube (FT) cells is higher than spermatozoa that do not attach. FT epithelial cells can distinguish normal and abnormal sperm chromatin. This study investigated the effects of sperm with a high-DNA fragmentation index (DFI) from men with unexplained repeated implantation failure (RIF) on the Toll-like receptor (TLR) signaling pathway in human FT cells in vitro. Methods: Ten men with a RIF history and high-DFI and 10 healthy donors with low-DFI comprised the high-DFI (>30%) and control (<30%) groups, respectively. After fresh semen preparation, sperm were co-cultured with a human FT epithelial cell line (OE-E6/E7) for 24 hours. RNA was extracted from the cell line and the human innate and adaptive immune responses were tested using an RT2 profiler polymerase chain reaction (PCR) array. Results: The PCR array data showed significantly higher TLR-1, TLR-2, TLR-3, TLR-6, interleukin 1α (IL-1α), IL-1β, IL-6, IL-12, interferon α (IFN-α), IFN-β, tumor necrosis factor α (TNF-α), CXCL8, GM-CSF, G-CSF, CD14, ELK1, IRAK1, IRAK2, IRAK4, IRF1, IRF3, LY96, MAP2K3, MAP2K4, MAP3K7, MAP4K4, MAPK8, MAPK8IP3, MYD88, NFKB1, NFKB2, REL, TIRAP, and TRAF6 expression in the high-DFI group than in the control group. These factors are all involved in the TLR-MyD88 signaling pathway. Conclusion: The MyD88-dependent pathway through TLR-1, TLR-2, and TLR-6 activation may be one of the main inflammatory pathways activated by high-DFI sperm from men with RIF. Following activation of this pathway, epithelial cells produce inflammatory cytokines, resulting in neutrophil infiltration, activation, phagocytosis, neutrophil extracellular trap formation, and apoptosis.

• Radiation Oncology Journal
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• v.13 no.4
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• pp.331-338
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• 1995

Purpose : To evaluate our clinical experience with the combination of teletherapy and intraluminal brachytherapy in patients with unresectable or inoperable esophageal cancers. Materials and Methods : From Nov 1989 to Mar 1993, twenty patients with esophageal cancer were treated with radical radiotherapy and intraluminal brachytherapy at Yonsei Cancer Center. All patients had squamous histolgy and stage distribution was as follows: stage II, 4($20{\%}$)patients; III, 15 ($75{\%}$)patients; IV, 1($5{\%}$)patients. A dose of S-12Gy/1-3weeks with intraluminal brachytherapy (3-5Gy/fraction) to 5mm from the outside of the esophageal tube using high dose rate Iridium-192 remotely afterloading brachytherapy machine was given 2 weeks after a total dose of 59-64Gy with external radiotherapy. Induction chemotherapy using cisplatin and 5-FU was performed in 13 patients with median 3 cycles(1-6 cycles), Response rate, local control rate, survival and complications were analysed retrospectively. Results : Two-year overall survival rate and median survival were $15.8{\%}$ and 13.5 months. Response rates were as follows complete remission(CR) 5($25{\%}$): partial remission a(PRa) 7($35{\%}$): partial remission b(PRb) 7($35{\%}$), no response(NR) 1($5{\%}$). Patterns of failure were as follows; local failure 13($65{\%}$), local and distant failure 3($15{\%}$), distant failure 0($0{\%}$). Ultimate local control rate was $20{\%}$. Treatment related complications included esophageal ulcer in two patients and esophageal stricture in one. Conclusion : Though poor local conrol rate, median survival was improved as compared with previous results of radiation therapy alone(8months) and chemoradiation combined treatment(11 months) in Yonsei Cancer Center High-dose-rate intraluminal brachytherapy following external irradiation is an effective treatment modality with acceptable toxicity in esophageal cancer.

• Journal of Chest Surgery
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• v.26 no.6
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• pp.475-482
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• 1993

90 patients[75 men and 15 women] with the thoracic disease underwent video-assisted thoracic surgery[VATS] during the period March 1992 to February 1993. The thoracic diseases were classified into two groups of spontaneous pneumothorax and general thoracic patients and they were 66 and 24, respectively.The mean size of the tumor resected was 4.3 $\pm$ 2.0 cm x 3.3 $\pm$ 1.1 cm x 2.7 $\pm$ 1.0 cm. The mean time of anesthesia and operation were 90.0 $\pm$ 19.9 min and 43.7 $\pm$ 13.1 min in spontaneous pneumothorax group and 123.3 $\pm$ 40.3 min and 62.8 $\pm$ 32.2 min in general thoracic group. The mean period of postoperative chest tube drainage and hospital stay were 5.0$\pm$ 5.5 days and 6.6 $\pm$ 7.4 days in spontaneous pneumothorax group and 3.5$\pm$ 1.6 days and 9.5 $\pm$ 6.1 days in general thoracic group. The indications of VATS were 71 pleural disease[78.9%: 66 spontaneous pneumothorax; 3 pleural effusions ; 1 pleural paragonimus westermanii cyst; 1 malignant pleural tumor with metastasis to the lung], 9 mediastinal disease[10.0%: 5 benign neurogenic tumor; 2 pericardial cyst; 1 benign cystic teratoma; 1 undifferentiated carcinoma], 8 pulmonary parenchymal disease[8.9%: 3 infectious disease ; 3 interstitial disease ; 2 malignant tumor ], and 2 traumatic cases of exploration and removal of hematoma[2.2%]. The applicated objectives of VATS were diagnostic[ 7 ], therapeutic[ 67 ] and both[ 16 ] and the performed procedures were pleurodesis[ 66 ], wedge resection of lung[ 59 ], parietal pleurectomy[ 11 ], removal of benign tumor[ 9 ], excision and/or biopsy of tumor[ 4 ], pleural biopsy and aspiration of pleural fluid[ 3 ] and exploration of hemothorax and removal of hematoma in traumatic 2 patients. The complication rate was 24.2%[ 16/66 ] in the spontaneous pneumothorax group and 8.3%[ 2/24 ] in the general thoracic group and so overally 20.0%[ 18/90 ]. The mortality within postoperative 30 days was 2.2%[ 2/90 ], including 1 acute renal failure and 1 respiratory failure due to rapid progression of pneumonia. The conversion rate to open thoracotomy during VATS was 5.6%[ 5/90 ], including 2 immediate postoperative massive air leakage, 1 giant bullae, 1 malignant pleural tumor with metastasis to lung and 1 pulmonary malignancy. The successful cure rate of VATS was 75.8%[ 50/66 ] in the spontaneous pneumothorax group and 76.5%[ 13/17 ] in the general thoracic group and the successful diagnostic rate was 100%[ 7/7 ]. In conclusion, although prospective trials should be progressed to define the precise role of VATS, the VATS carries a low morbidity and mortality and high diagnostic and therapeutic success rate and now can be effectively applicated to the surgical treatment of the extensive thoracic disease.