• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.37-46
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• 1981

This study was undertaken to evaluate the pulpal responses to the pulp-capping materials such as glutaraldehyde and formocresol in pulpotomy technique, especially in the primary dentition. Mandibular primary canines and molars of 5 dogs (aged about 8-9 weeks)were selected for this study. The intervals of observation for histologic study of pulpotomized primary teeth with 2% glutaraldehyde, formocresol and calcium hydroxide in the usual manner ranged from 2 hours, 1 week, 2 weeks, 3 weeks and 5 weeks after experiments respectively. Each specimens were fixed with 10% formalin and decalcified in 5% nitric acid. All slides were stained with Hematorylin-Eosin and examined histopathologically. The results were as follows; 1. In calcium hydroxide groups, formation of dentin bridge was initiated in 1 week after experiments and completed in 5 weeks after experiments. 2. Formation of dentin bridge was not seen, whereas necrosis of pulp tissue was noted, in formocresol and glutaraldehyde groups. 3. Duration of tissue reactions and tissue changes were similar, in formocresol and glutaraldehyde groups. 4. In formocresol and glutaraldehyde groups, amputation surfaces of the pulp were covered with blood clots, beneath which coagulation necrois was noted, but inflammatory cells were not prominent, in 2 hours and 1 week after experiments. But coagulation necrosis was proceeded to the apical portion, accompanied by infiltration of inflammatory cells, since 2 weeks after experiments. And suppuration or gangrene of the pulp tissue were noted in 3 weeks and 5 weeks groups. 5. Suppuration or gangrene of pulp seemed to provoke the resorption of dentin wall, and inflammatory changes and resorption of roots were noted in the periodontal membrane near the periapical region. 6. As compared with calcium hydroxide groups, resorption of the root was pronounced in form or cresol and glutaraldehyde groups. Effects of medicaments to the succedaneous tooth germ were not seen.

• Clinics in Shoulder and Elbow
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• v.26 no.3
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• pp.276-286
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• 2023

Background: The transosseous anchorless repair (ToR) technique was recently introduced to avoid suture anchor-related problems. While favorable outcomes of the ToR technique have been reported, no previous studies on peri-implant cyst formation with the ToR technique exist. Therefore, this study compared the clinical outcomes and prevalence of peri-implant cyst formation between the ToR technique and the conventional transosseous equivalent technique using suture anchors (SA). Methods: Cases with arthroscopic rotator cuff repair (ARCR) between 2016 and 2018 treated with the double-row suture bridge technique were retrospectively reviewed. Patients were divided into ToR and SA groups. To compare clinical outcomes, 19 ToR and 57 SA cases without intraoperative implant failure were selected using propensity score matching (PSM). While intraoperative implant failure rate was analyzed before PSM, retear rate, peri-implant cyst formation rate, and functional outcomes were compared after PSM. Results: The intraoperative implant failure rate (ToR, 8% vs. SA, 15.3%) and retear rate (ToR, 5.3% vs. SA, 19.3%) did not differ between the two groups (all P>0.05). However, peri-implant cysts were not observed in the ToR group, while they were observed in 16.7% of the SA group (P=0.008). Postoperative functional outcomes were not significantly different between the two groups (all P>0.05). Conclusions: The ToR technique produced comparable clinical outcomes to conventional techniques. Considering the prospect of potential additional surgeries, the absence of peri-implant cyst formation might be an advantage of ToR. Furthermore, ToR might reduce the medical costs related to suture anchors and, thereby, could be a useful option for ARCR. Level of evidence: III.

• Textile Coloration and Finishing
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• v.19 no.1 s.92
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• pp.1-11
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• 2007

Dyeing of polyester/cotton blends is usually carried out through the two-bath or one-bath two-step dyeing method using proper disperse dyes and reactive dyes for each fiber. However, the dyeing requires relatively long and complicated procedure as well as there are some problems such as lower dyeability. In the present study, new one-bath one-step dyeing process was investigated using disperse dyes having amino groups and hetero-bifunctional bridge compound(DBDCBS) including dichloro-s-triazinyl groups and ${\alpha},{\beta}$-dibromopropionylamido groups to improve the dyeability of cotton component in polyester/cotton blends. And the one-bath dyeing properties of polyester/cotton blends was evaluated by various dyeing conditions such as pH, temperature and dye concentration, The optimum dyeing condition was pH 4 and $110-120^{\circ}C$. Color fastness were relatively good because of the colvalent bond formation between DBDCBS-reacted cotton fiber and disperse dye.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1149-1155
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• 2007

The transition area between a bridge and an earthwork is one of the weakest area of track because of the track geometry deterioration caused unequal settlement of backfill of abutment. In case of a ballastless track, the approach slab is installed to prevent the phenomenon. But, if there is occurred the inclined displacement on the approach slab by a settlement of the foundation or formation, the track is also under the inclined displacement. And this defect causes reducing the running stability of a vehicle, the riding comfort of passengers, and the deteriorations of track by excessive impact subjected to the track. In this study, parametric studies were performed to know what is the allowable displacement limit on the approach slab to avoid such a bad effect. The length and amount of unequal settlement of the approach slab was adopted as parameter for numerical analysis. And car body accelerations, variations of wheel force and rail stress and uplift force induced on a fastener clip are investigated. From the result, resonable settlement limits of an approach slab according to slab length was suggested.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.231-238
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• 2001

To investigate the underground structure of shallow water, Han-river near Yangsou-Ri, high resolution hydroacoustic measurements were carried out for the engineering design of railroad bridge. The acoustic source was a Boomer with an energy of 90 to 280J and in a frequency range up to about 16KHz. The reflected signals were received by using both traditional hydrophones(passive element) and a specially devised receiver unit(active element) mainly composed of piezofilms and preamplifier. They are connected to the "SUMMIT" data acquisition system(DMT-GeoTec company), where the sampling interval was set to 1/32㎳. The source position was continuously monitored by a precision DGPS system whose positioning accuracy was on the order of loom. For the quality control purposes, two different source-receiver geometries were taken. That is to say, the measurements were repeated along the profile everytime depending on the different source energy(175J, 280J), the receiving elements(passive, active) and two different source-receiver geometries. It was shown that the data resolution derived from a proper arrangement with the active hydrophone could be greatly enhanced and hence the corresponding profile section caused by the regular data processing system "FOCUS" accounted excellently for the underground formation below the shallow water.w the shallow water.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.287-287
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• 2010

We report a new direct patterning method, called liquid bridge-mediated nanotransfer molding (LB-nTM), for the formation of two- or three-dimensional structures with feature sizes between tens of nanometers and tens of micron over large areas. LB-nTM is based on the direct transfer of various materials from a mold to a substrate via a liquid bridge between them. This procedure can be adopted for automated direct printing machines that generate patterns of functional materials with a wide range of feature sizes on diverse substrates. Arrays of TIPS-PEN TFTs were fabricated on 4" polyethersulfone (PES) substrates by LB-nTM using PDMS molds. An inverted staggered structure was employed in the TFT device fabrication. A 150 nm-thick indium-tin oxide (ITO) gate electrode and a 200 nm-thick SiO2dielectric layer were formed on a PES substrate by sputter deposition. An array of TIPS-PEN patterns (thickness: 60 nm) as active channel layers was fabricated on the substrate by LB-nTM. The nominal channel length of the TIPS-PEN TFT was 10 mm, while the channel width was 135 mm. Finally, the source and drain electrodes of 200 nm-thick Ag were defined on the substrate by LB-nTM. The TIPS-PEN TFTs can endure strenuous bending and are also transparent in the visible range, and therefore potentially useful for flexible and invisible electronics.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.453-462
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• 2014

The levee and bridge pier in estuary of the Hangang River are exposed in a dangerous condition due to bank erosion and local scouring occurred since the summer season in 2011. At first, it is presumed that the high sandbar formed in river channel of the study area was an important element in the occurrence of bank erosion and local scouring. It can be presumed that the record-breaking depth of freezing due to cold wave for the long term during the winter season between 2010 and 2011 as well as the heavy intensive rainfall of 2011 had a decisive effect on the first damage of A section. The second damage of B section mainly occurred around the bridge pier constructed on the high water channel before it was washed away during the winter season between 2011 and 2012. It is considered that the second damage was caused by ice formation and ice floes.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.84.1-84.1
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• 2014

We report the spatial distribution of early-type stars and pre-main-sequence (PMS) stars around the starburst type young open cluster Westerlund 2. The early-type were selected from UBVI photometric data, while the PMS members were identified from their X-ray emission and mid-infrared excess. The northern clump of the cluster is composed mainly of PMS stars detected in both optical and X-ray and seems to be coeval to the cluster, while PMS stars in the bright bridge region are highly obscured in optical wavelength. The bright bridge appear to be an on-going star forming region possibly triggered by the strong radiation field from both sides-massive stars in Westerlund 2 and WR 20b. We also found that there are many early-type stars not only in the cluster but also farther from the cluster up to several times of the cluster radius. These early-type stars are well aligned from east to southwest of the cluster. We conclude these early-type stars are members of an OB association in the RCW 49 nebula. This report indicates there is a complex star formation history in Westerlund 2 and its surrounding H II region, the RCW 49 nebula.

• Journal of Plant Biology
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• v.37 no.1
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• pp.69-76
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• 1994

The present work was conducted to examine the effect of tobacco smoke solution, and its components such as nicotine and catechol treated separately on the root tip cells of Allium cepa L The mitotic abnormalities in root tip cells treated with those three components were increased linearly, while the mitotic index was decreased following concentrations of the components. Chromosomal abnormalities showed 29.7%, 15.8% and 13.0% in the treatment of tobacco smoke solution, nicotine, and catechol, respectively. The abonormalities were included polyploid, c-mitosis, stickness at metaphase, laggard, bridge formation at anaphase or telophase, and micronucleus, abnormal nucleus at interphase, after the treatment of the components for 24 hours. hours.

• Steel and Composite Structures
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• v.50 no.3
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• pp.363-374
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• 2024

The fatigue life of steel wire is affected not only by fatigue load, but also by corrosion environment in service period. Specially, the corrosion pit will lead to stress concentration on the surface of steel wire inducing the formation of fatigue cracks, and the fatigue cracks will accelerate the corrosion process. Therefore, the corrosion fatigue of steel wire is a coupling effect. In this study, the corrosion-fatigue coupling life curve is derived with considering corrosion-fatigue pitting stage, corrosion-fatigue short crack stage and corrosion-fatigue long crack stage. In addition, the stress concentration factors of different corrosion pits are calculated by COMSOL software. Furthermore, the effect of corrosion environment factors, that is, corrosion rate, corrosion pit morphology, frequency and action factor of fatigue load, on fatigue life of steel wire is analyzed. And then, the corrosion-fatigue coupling life curve is compared with the fatigue life curve and fatigue life curve with pre-corrosion. The result showed that the anti-fatigue performance of the steel wire with considering corrosion-fatigue coupling is 68.08% and 41.79% lower than fatigue life curve and fatigue life curve with pre-corrosion. Therefore, the corrosion-fatigue coupling effect should be considered in the design of steel wire.