• Title/Summary/Keyword: protector

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Expression of Thiol-Dependent Protector Protein from Yeast Enhances the Resistance of Escherichia coli to Menadione

  • Park, Jeen-Woo;Ahn, Soo-Mi;Kim, Eun-Ju;Lee, Soo-Min
    • BMB Reports
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    • v.29 no.6
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    • pp.513-518
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    • 1996
  • A soluble protein from Saccharomyces cerevisiae specifically provides protection against a thiolcontaining oxidation system but not against an oxidation system without thiol. This 25-kDa protein was thus named thiol-dependent protector protein (TPP). The role of TPP in the cellular defense against oxidative stress was investigated in Escherichia coli containing an expression vector with a yeast genomic DNA fragment that encodes TPP (strain YP) and a mutant in which the catalytically essential amino acid in the active site of TPP (Cys-47) has been replaced with alanine by site-directed mutagenesis (strain YPC47A). There was a distinct difference between these two strains in regard to viability, modulation of activities of superoxide dismutase and catalase, and the oxidative damage of DNA upon exposure to menadione. These results suggest that TPP may play a direct role in the cellular defense against oxidative stress by functioning as an antioxidant protein.

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A Study on the Analysis Method to API Wrapping that Difficult to Normalize in the Latest Version of Themida (최신 버전의 Themida가 보이는 정규화가 어려운 API 난독화 분석방안 연구)

  • Lee, Jae-hwi;Lee, Byung-hee;Cho, Sang-hyun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.29 no.6
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    • pp.1375-1382
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    • 2019
  • The latest version of commercial protector, Themida, has been updated, it is impossible to apply a normalized unpacking mechanism from previous studies by disable the use of a virtual memory allocation that provides initial data to be tracked. In addition, compared to the previous version, which had many values that determined during execution and easy to track dynamically, it is difficult to track dynamically due to values determined at the time of applying the protector. We will look at how the latest version of Themida make it difficult to normalize the API wrapping process by adopted techniques and examine the possibilities of applying the unpacking techniques to further develop an automated unpacking system.

A study on better wire protector of equipment on the Circulating Current in Catenary System (순환전류에 대한 전철설비 보호카바 개선 연구)

  • Kang, Seung-Wook;Kim, In-Chol;Kim, Hyo-Jin;Kim, Dae-Sik;Baek, Seong-Hyun;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.375-378
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    • 2007
  • In these days, Korea Railway apply simple catenary system to general lines and high speed lines of Korea Electric Railway. Circulation Current in catenary system frequently bring undesirable consequences. Namely, the Connector wire has many problems according to a flow of excessive circulation (or traction current) and a sudden rise of temperature on catenary when electric car or locomotive is running in high speed. The occurrence of events by the load increasement do considerable damages to peoples, organizations and systems. On a case by case accidents, the reeltype protective cover as part of various methods has some problems. In this project, we proposed the improved changes on the catenary system of a improvement and change of a messenger wire protector, improvement of connector wire's institution angle and of a replacement the connector wire with a dropper. Its tridimensional space limitation dictated the scale of the $32{\times}{\Phi}55$ to be as small as possible. It is easier to install than work by the existing cover on the messenger wire.

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Corneal Abrasion Occurred during Transconjunctival Blepharoplasty in a Patient with History of LASIK Operation (라식수술을 시행한 환자에서 결막절개를 통한 하안검성형술 시 발생한 각막손상)

  • Shin, Jong-In;Kwon, In-Oh;Kim, Chang-Yeon
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.543-546
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    • 2011
  • Purpose: LASIK, one of the currently popular ophthalmic procedures, can sometimes result in dry eye symptoms. In the patient who had underwent LASIK operation, the periorbital surgery may be more likely to lead to such a complication as dry eye symptom. We would like to report a case of corneal abrasion occurred after transconjunctival blepharoplasty in post-LASIK state and suggest the method about preventing the complication. Methods: A 30-year-old female patient underwent transconjunctival blepharoplasty and microfat graft into the face. She had history of LASIK operation 2 years ago. Corneal protector was applied to both eye during transconjunctival operation. After the surgery, she complained of visual blurring at left side. Ophthalmic examination revealed corneal abrasion of left eye. Results: Cornea protecting lens was applied to left eye for 2 weeks. Steroid and antibiotic eye drops were applied for relieving the symptoms and the prevention from progressing of complication. After 1 week, visual power and acuity was recovered to preoperative state. No other specific complications happened. Conclusion: Post-LASIK patient may have possibility of decreased corneal sensation and tear production. Preoperative ophthalmic examination is recommended for the prevention of complication. When corneal protector is applied, we suggest Optagel$^{(R)}$ as a useful lubricant.

Influential processes for the acceptance of protectors toward emergency care for patient based on an elaboration likelihood model (보호자의 응급처치 수용의도에 관한 연구: 정교화 가능성 모델 중심)

  • Hwang, Ji-Young;Kim, Yun-Kwon;Kim, Ki-Young
    • The Korean Journal of Emergency Medical Services
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    • v.19 no.3
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    • pp.51-68
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    • 2015
  • Purpose: This study validated the influential relations between the effects of emergency care quality, credibility of 119 emergency medical technicians (119 EMTs), and perceived usefulness and attitude of emergency care, focusing on the moderating effect of protectors' characteristics (education, experience, age, and recognition of patient severity). Methods: This study was based on elaboration likelihood and technology acceptance models. In total, 172 protectors with experience in utilizing prehospital service were surveyed from April 1 to July 31, 2011. Results: The results showed that the emergency care quality and the credibility of 119 EMTs were the main determinants of the perceived usefulness and attitude of emergency care, irrespective of the protector's characteristics (p <.001). In addition, the findings showed that the protector's intention of emergency care had a moderating role. The impact of the quality of emergency care on its perceived usefulness was greater for high-level protectors (p <.001). By contrast, the impact of the credibility of 119 EMTs on the perceived usefulness of emergency care was greater for low-level protectors (p <.001). Conclusion: The protectors' characteristics have different influences on the relations between the effects of emergency care quality, the 119 EMT credibility, and the perceived usefulness and attitude of emergency care.

Review about the Lightning Protection System for Ground Facilities of Anti-aircraft Weapons System (뇌 보호시스템의 대공무기체계 지상시설 적용에 대한 고찰)

  • Jung, Kyoungwook;Shim, Donghyouk;Son, Donghyeop
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.3
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    • pp.339-347
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    • 2021
  • Recently, the incidence of lightning in Korea has been increasing more and more. The damage caused by lightning is also getting worse. Lightning protection system is a prerequisite, not a sufficient condition. Considering the characteristics of lightning, there is a high frequency of lightning strikes in highlands. So, high grades of LPS should be applied to ground facilities of anti-aircraft weapons systems. 4-Level LPS was applied on groung facilities of anti-aircraft weapons system based on lightning incidence rate in past. There are some possibilities of damage from lightning in anti-aircraft weapons system. So, we have to readjust the LPS level with grounding, lightning rods and surge protect device based on lightning incidence rate in now days. Propose 2-level LPS and design with lightning rods, surge protector, separated grounding in this paper.

FEM Analysis of the Effects of Mouth guard material properties on the Head and Brain under Mandibular Impact (구강보호장치의 재료적인 특성이 하악골 충격 시악골 및 두부에 미치는 영향에 관한 유한요소분석)

  • Kang, Nam-Hyun;Kim, Hyung-Sub;Woo, Yi-Hyung;Choi, Dae-Gyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.4
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    • pp.325-334
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    • 2008
  • Statement of problem & Purpose: The purpose of this study was to investigate the effect of a mouth guard material properties on the skull and brain when they were under impact loads on mandible. Material and methods: Two customized mouth protectors having different material propeerst ieach other were made for a female Korean who had no history of brain trauma, no cerebral diseases, nomal occlusion and natural dentition. The 3D finite element model of human skull and brain scanned by means of computed tomography was constructed. The FEM model of head was composed of 407,825 elements and 82,138 nodes, including skull, brain, maxilla, mandible, articular disc, teeth and mouth guard. The stress concentrations on maxillary teeth, maxilla and skull with two mouth guards were evaluated under oblique impact load of 800N onto mandibular 3 loading points for 0.1sec. And the brain relative displacement was compared in two different mouth guard materials under same condition. Result and Conclusion: The results were as follows; 1. In comparison of von Mises stress on maxillary teeth, a soft mouth guard material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 2. In comparison of von Mises stress on maxilla and skull, A soft mouth protector material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 3. For impact loads on mandible, there were more stress concentrated area on maxilla and skull with hard mouth guard than soft with mouth protector. 4. For impact loads on mandible, brain relative displacement had little relation with mouth guard material properties. In results of this study, soft mouth guard materials were superior to hard mouth guard materials for mandible impact loads for prevention of sports injuries. Although the results of this study were not enough to figure out the roles of needed mouth guard material properties for a human head, we got some knowledge of the pattern about stress concentration and distribution on maxilla and skull for impact loads with soft or hard mouth protector. More studies are needed to substantiate the relationship between the mouth guard materials and sports injuries.

Reinforcement of Shotcrete Lining on the Side Wall of Tunnel in Enlargement of Existing ASSM Road Tunnel (측벽부 숏크리트 보강에 의한 재래식 도로터널 단면확대)

  • Kim, Donggyou;Shin, Youngwan
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.12
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    • pp.81-89
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    • 2012
  • The existing tunnel in urban area can be enlarged because of requirement of road-widening by traffic growth. The protector with rectangular cross section can be set up in the tunnel, which will be constructed for enlargement of width, to solve traffic jam around the tunnel. It is impossible to install the rockbolt in the lower area of tunnel due to a limited space between the protector and cutting surface. The objective of this study is to suggest the method of shotcrete thickness increase instead of rockbolt installation in the side wall of tunnel for the stability of tunnel. Numerical analysis was performed to evaluate displacement at the crown of tunnel, convergence of tunnel, and stress in shotcrete lining in 3-lane and 4-lane NATM tunnels enlarged from 2-lane conventional tunnel. There were three types of analysis condition, rockbolt installation, no rockbolt installation, and increase of shotcrete thickness without rockbolt in the side wall of tunnel. There was no difference on the displacement at the crown and the convergence of upper tunnel. In the lower tunnel, the convergence in case of no rockbolt installation was larger as maximum 1.3mm than that in case of rockbolt installation. The stress in shotcrete lining in case of no rockbolt installation was larger as maximum 1.3MPa than that in case of rockbolt installation. Numerical analysis was performed to compare the behavior of shotcrete with rockbolt with that of shotcrete, which its thickness was increased, without rockbolt. The shotcrete has an increase of 20%(250mm ${\rightarrow}$ 300mm, 4-lane tunnel)~25%(200mm ${\rightarrow}$ 250mm, 3-lane tunnel) in its thickness to reduce the stress in shotcrete lining. The behavior of shotcrete lining increased the shotcrete thickness by 20%~25% was similar to that of existing shotcrete lining with rockbolt.

Use of Mouthguard for Prevention of Oral and Maxillofacial Injury (구강악안면영역의 외상방지를 위한 마우스가드의 사용)

  • Shim, Young-Joo;Kang, Jin-Kyu
    • Journal of Oral Medicine and Pain
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    • v.37 no.4
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    • pp.251-256
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    • 2012
  • With today's heightened interest in quality of life, leisure and sports activities were popular in the general public. Accordingly, the incidence of oral and maxillofacial injury are also rising. Use of a mouth protector to prevent the trauma of the oral and maxillofacial region is growing in importance, and among the mouth protector the mouthguard is the most commonly used. Mouthguard has been suggested to protect injuries by (1) preventing tooth injuries by absorbing and deflecting blows to the teeth; (2) shielding the lips, tongue, and gingival tissues from laceration; (3) preventing opposing teeth from coming into violent contact; (4) providing the mandible with resilient support, which absorbs an impact that might fracture the unsupported angle or condyle of the mandible; (5) preventing neck and cerebral brain injuries. Although mouthguard is effective for prevention of oral and maxillofacial injury, it is not widespread to athletes or general public and they are lack of awareness about the importance of mouthguard. We present the types and materials of mouthguard, things to consider when mouthguard fabrication, and the usage. This should be helpful in awareness about the importance and popularization of mouthguard.

EFFECT OF FLUORIDE VARNISH ON DEVELOPMENT OF ARTIFICIAL CARIES (불소 바니쉬가 인공 우식 병소의 발생에 미치는 영향)

  • Cho, Nan-Ju;Lee, Sang-Ho;Lee, Nan-Young
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.4
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    • pp.613-622
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    • 2007
  • The purpose of this study was to evaluate the effect of fluoride varnish on prevention of enamel demineralization. Eighty bovine enamel blocks were divided randomly into 4 groups of 20 specimens: Group I served as the control with no topical application of fluoride. Group II was treated with APF gel for 4 minutes. Group III was treated with Fluor $Protector^{(R)}$. Group IVV was treated with $CavityShield^{TM}$. After 24 hours of treatment, samples were brushed with a soft bristled tooth brush to stimulate normal mechanical wear of varnish. Early caries lesions were produced by placing each specimen into demineralization solution at pH 4.0 for 48 hours. Then the optical density of the lesions was measured by light fluorescence induced by plasma light and the surface microhardness were measured by the vicker's hardness test. The results were as follows: 1. The optical densities of group III, IV were significantly higher than that of group II, but no significant difference was noted between group III and IV. 2. The surface microhardness of group IV was the highest, followed by group III, II, and I(p<0.05). 3. There were no significant differences between group III and IV in optical density. However, the surface microhardness of group IV was significantly higher than that of group III. The results of present study indicate that the fluoride varnish is more effective than APF gel for prevention of dental caries.

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