• Journal of Microbiology
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• v.45 no.1
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• pp.34-40
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• 2007

In budding yeast, G2/M transition is tightly correlated with bud morphogenesis regulated by Swel and septin that plays as a scaffold to recruits protein components. BNI5 isolated as a suppressor for septin defect is implicated in septin organization and cytokinesis. The mechanism by which Bni5 regulates normal septin function is not completely understood. Here, we show that Bni5 phosphorylation is required for mitotic entry regulated by Swel pathway. Bni5 modification was evident from late mitosis to G1 phase, and CIP treatment in vitro of affinity-purified Bni5 removed the modification, indicative of phosphorylation on Bni5. The phosphorylation-deficient mutant of BNI5 (bni5-4A) was defective in both growth at semi-restrictive temperature and suppression of septin defect. Loss of Bni5 phosphorylation resulted in abnormal bud morphology and cell cycle delay at G2 phase, as evidenced by the formation of elongated cells with multinuclei. However, deletion of Swel completely eliminated the elongated-bud phenotypes of both bni5 deletion and bni5-4A mutants. These results suggest that the bud morphogenesis and mitotic entry are positively regulated by phosphorylation-dependent function of Bni5 which is under the control of Swel morphogenesis pathway.

• Journal of Microbiology
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• v.45 no.3
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• pp.227-233
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• 2007

In budding yeast, septin plays as a scaffold to recruits protein components and regulates crucial cellular events including bud site selection, bud morphogenesis, Cdc28 activation pathway, and cytokinesis. Phosphorylation of Bni5 isolated as a suppressor for septin defect is essential to Swe1-dependent regulation of bud morphogenesis and mitotic entry. The mechanism by which Bni5 regulates normal septin function is not completely understood. Here, we provide evidence that Bni5 phosphorylation is important for interaction with septin component Cdc11 and for timely delocalization from septin filament at late mitosis. Phosphorylation-deficient bni5-4A was synthetically lethal with $hof1{\Delta}$. bni5-4A cells had defective structure of septin ring and connected cell morphology, indicative of defects in cytokinesis. Two-hybrid analysis revealed that bni5-4A has a defect in direct interaction with Cdc11 and Cdc12. GFP-tagged bni5-4A was normally localized at mother-bud neck of budded cells before middle of mitosis. In contrast, at large-budded telophase cells, bni5-4A-GFP was defective in localization and disappeared from the neck approximately 2 min earlier than that of wild type, as evidenced by time-lapse analysis. Therefore, earlier delocalization of bni5-4A from septin filament is consistent with phosphorylation-dependent interaction with the septin component. These results suggest that timely de localization of Bni5 by phosphorylation is important for septin function and regulation of cytokinesis.

• Journal of the Korean Society of Propulsion Engineers
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• v.7 no.4
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• pp.73-79
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• 2003

The tensile strength test and the analysis for the section of brazing were performed in the cases of materials used for combustion chamber of regeneratively cooled liquid rocket engine. BNi-2 and BNi-7 based on nickel were used for brazing as filler metal. The properties of material and filler metal were analyzed by tensile strength test and metal microscope for 12 specimens. The tensile-strength of brazing for chrome-copper alloy and other kinds of alloy was higher than that of chrome-zirconium-copper alloy and other kinds of alloy The tensile strength in the case of BNi-2 as filler metal was higher than that of BNi-7 because the wetting property of BNi-2 was better than that of BNi-7.

• 연구논문집
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• s.27
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• pp.201-208
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• 1997

To improve the joining characteristics of metallic converter substrate for exhaust gas cleaning, high temperature brazing process has been studied. In this study, the effect of chemical composition of brazing filler metal on the oxidation behavior of brazed joints was investigated closely. Brazing was carried out at $1200^\circC$ in vacuum furnace using nickel-based filler metals : BNi-5 powder(Ni-Cr-Si base alloy) and MBF-50 foil(Ni-Cr-Si-B). The MBF-50 containing 1-1.5 wt%B showed relatively poor oxidation resistance of the brazed joints compared to BNi-5, because of the faster invasion of oxygen through the Kirkendal voids along the interface of mother alloy/filler metal.

• Journal of Korean Neurosurgical Society
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• v.64 no.5
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• pp.827-836
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• 2021

Objective : Trigeminal neuralgia is one of the most common causes of facial pain. Our aim is to investigate the efficacy and borders of percutaneous radiofrequency thermocoagulation in the treatment of trigeminal neuralgia. Methods : Between May 2007 and April 2017, 156 patients with trigeminal neuralgia were treated with radiofrequency thermocoagulation. These 156 patients underwent 209 procedures. In our study, we investigated the early and late results of percutaneous radiofrequency thermocoagulation under guiding fluoroscopic imaging in the treatment of trigeminal neuralgia. Barrow Neurological Institute (BNI) pain scale was used for grading the early results. In addition, Kaplan-Meier survival analysis was used to assess long-term outcomes. Of the 156 patients who underwent radiofrequency thermocoagulation for trigeminal neuralgia, 45 had additional disease. Patients with this condition were evaluated with their comorbidities. Early and late results were compared with those without comorbidity. Results : In 193 of 209 interventions BNI pain scale I to III results were obtained. Out of the 193 successful operation 136 patients (65.07%) were discharged as BNI I, 14 (6.70%) as BNI II, 43 (20.58%) as BNI III. Sixteen patients (7.65%) remained uncontrolled (BNI IV and V). While the treatment results of trigeminal neuralgia patients with comorbidity seem more successful in the early period, this difference was not observed in follow-up examinations. Conclusion : Finally, we concluded that percutaneous radiofrequency thermocoagulation of the Gasserian ganglion is a safe and effective method in the treatment of trigeminal neuralgia. However, over time, the effectiveness of the treatment decreases. Neverthless, the reapprability of this intervention gives it a distinct advantage.

• Journal of Korean Neurosurgical Society
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• v.50 no.5
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• pp.446-452
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• 2011

Objective : We retrospectively investigated the long-term results of percutaneous radiofrequency thermocoagulation (RFT) using fluoroscopic image-guidance for treatment of trigeminal neuralgia. Methods : A total of 38 patients diagnosed and treated with RFT as an idiopathic trigeminal neuralgia were investigated. To minimize the risks related to conventional technique based on cutaneous landmarks, and to eliminate the need to frequent reposition of cannula, we adopted a technique of image-guided fluoroscopic cannulation of the foramen ovale. To minimize sensory complication following thermal lesion, our target response was a generation of a lesion with mild to moderate hypalgesia rather than dense hypalgesia. Results : The immediate pain-relief was achieved in all patients underwent RFT. With mean duration of follow-up of 38.2 months (range,12-72), 11 (28.9%) experienced recurrence of pain. The mean timing of recurrence was 26.1 months (range,12-46). A 42.7% recurrence rate was estimated by Kaplan-Meier analysis for the 38 patients at 46 months; 20.2% within 2 years, 29.1% within 3 years. In the long-term, 27 patients (71%) and 6 patients (15.8%) showed Barrow Neurological Institute (BNI) score I and BNI score II responses. Three (7.9%) patients was assessed as BNI score III, 2 patients (5.3%) showed BNI score IV response. As a complication, troublesome dysesthesia occurred in 3 of 38 patients (7.9%), however, there was no permanent cranial nerve palsy or morbidity. Conclusion : These results indicates that RFT under fluoroscopic image-guided cannulation of foramen ovale is a safe, effective, and reliable means of treating trigeminal neuralgia.

• 연구논문집
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• s.29
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• pp.141-149
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• 1999

Brazing of Fe-Cr-Al alloy was carried out at $1200^{\circ}C$ in vacuum furnace using nickel-based filler metals : BNi-5 powder(Ni-Cr-Si-Fe base alloy} and MBF-50 foil (Ni-Cr-Si-B). The effect of boron content on the stability of oxide scale on the brazed joint was investigated by means of cyclic oxidation test performed at $1050^{\circ}C$ and $1200^{\circ}C$. Apparently, the joints brazed with MBF-50 containing boron showed relatively stable oxidation rates compared to boron-free BNi-5 at both temperatures. However, it was considered that the slower weight loss of MBF-50 brazed specimen wasn’t resulted from the low oxidation rate but from the spallation of oxide layer. The oxide layer consisted of thick spinel oxide on the surface and $Al_2 O_3$ internal oxide layer along the interface between mother alloy and braze, the mother alloy was also eroded seriously by the formation of spinel oxides such as $FeCr_2 O_4$ and $NiCr_2 O_4$ on the surface, likely to be induced by the change of oxide forming mechanism due to diffusion of boron from the braze. On the contrary, the joint brazed with BNi-5 showed the good oxidation resistance during the cyclic oxidation test. It seems that the oxidation can be retarded by the formation of stable $Al_2 O_3$ layer at the surface.

• Journal of Sensor Science and Technology
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• v.16 no.5
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• pp.389-393
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• 2007

Soft ferromagnetic materials are very useful for many sensors using magnetic materials demanding high permeability, low coercivity and low hysteresis loss. Among them, FeCoSiBNi amorphous magnetic films show a good impedance change (about 5.01 %/Oe, at 10 MHz) by the exterinal magnetic field in this experiment. The magnetic films are produced by melt-spun method, one of the rapid solidification process. Ribbon shape wires were made from the films, and let them annealed in DC magnetic field to increase the maximum Giant Magneto Impedance ratio. Field annealing decreases the stress and changes the effective anisotropy. Thus, we can find that the impedance change (200.47 %) is improved and the fabricated magnetic wire has characteristics of good sensor element.

• Korean Journal of Materials Research
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• v.15 no.6
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• pp.399-407
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• 2005

The effect of IN738 additive powder on microstructure and mechanical properties of the wide-gap region brazed with BNi-3 filler metal powder was investigated. The wide-gap brazing was conducted in a vacuum of $2\times10^{-5}torr\;at\;1200^{\circ}C$ with various powder mixing ratios of additive to filler powders. The microstructures of the wide-gap brazed region were analyzed by SEM and AES. The region brazed with only BNi-3 filler metal powder had a microstructure consisted of proeutectic, binary eutectic and ternary eutectic structure, while that brazed with a mixture of IN738 additive powder and BNi-3 filler metal powder had a microstructure consisted of IN738 additive powder, binary eutectic of $Ni_3B-Ni$ solid solution and (Cr, W)B. The fracture strength of the wide-gap brazed region was about 680 MPa regardless of the additive powder mixing ratios. Cracks were initiated at the (Cr, W)B and binary eutectic of $Ni_3B-Ni$ solid solution, and propagated through them in the wide-gap brazed region, which lowered the fracture strength of the region.

• Journal of the Korean Society for Heat Treatment
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• v.22 no.4
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• pp.210-216
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• 2009

Stainless steel EGR cooler of diesel engine is widely used to prevent the corrosion due to the content of sulfur in diesel fuel. The strength of brazed joint between stainless steel materials is very important. It is essential to observe the spreading ratio of the filler metals under the condition of deoxidation or vacuum during heating process. In this experiment, spreading ratio was tested to find the optimum brazing condition for stainless steel using brazing filler metals of FP-613, BNi-2 and BNi-5 on sus304 and sus410. Anti-corrosion tests were also performed on the above filler metals with solution of 5% $H_2SO_4$, 65% $HNO_3$ and 5% $NH_4OH$. Consequently FP-613 has good ability for anti-corrosion with 30% of chromium content compared with other filler metals. The optimum brazing conditions are occurred at $960^{\circ}C$ for 90 min. and at $1090^{\circ}C$ for 50 min. at the same degree of vacuum, $2{\sim}3{\times}10^{-3}$ Torr.