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감마선 조사에 의한 소목추출물의 색상변화 및 항산화 활성 평가
권형준,정우희,박혜란,신동화,조성기,Kwon, Hyung-Jun,Jung, U-Hee,Park, Hae-Ran,Shin, Dong-Hwa,Jo, Sung-Kee 한국식품영양과학회 2007 한국식품영양과학회지 Vol.36 No.8
본 연구에서는 소목 열수추출물을 용매 순차 분획하여 얻은 EtOAc 분획물을 가지고 감마선 조사(100 kGy)한 후 색상 변화와 항산화활성 향상 변화를 평가하였다. 평가시험으로서 소목 용매 순차 분획물과 선정된 EtOAc 분획물에 감마선을 조사(100 kGy)후 DPPH 라디칼 소거활성에서 4가지 유기용매 분획물(chloroform, ethylacetate, n-butanol, $H_{2}O$) 중 EtOAc 분획물의 전자공여능 $IC_{50}$ 값이 비조사구와 조사구 각각 0.71 및 0.61 ${\mu}g/mL$로 현저히 높았으며, 비조사구와 조사구 각각 $38.5{\sim}91.5%$ 및 $45.7{\sim}94.8%$의 라디칼 소거활성을 보여 조사구의 활성이 높게 나타났다. 또한 감마선 조사(100 kGy)한 EtOAc 분획물의 색상 변화는 명도(L값) 및 황색도(b값)의 경우 조사 후 증가한 반면, 적색도(a값)는 감소하였다. 총 페놀 함량은 비조사구와 조사구 각각 865 및 1195 mg/g으로 조사 후 유의적인 차이를 보였다(p<0.05). Superoxide anion radical 소거활성 시험에서 EtOAc 분획물의 비조사구와 조사구 각각 $16.3{\sim}84.7%$ 및 $20.2{\sim}92.5%$로 조사구의 superoxide anion radical에 대한 소거활성이 높게 나타내었고 첨가수준 50 ${\mu}g/mL$ 이상의 농도에서는 60% 이상의 소거력을 나타내었다. 지질과산화 억제 시험에서 EtOAc 분획물의 비조사구와 조사구 각각 $14.6{\sim}85.6%$ 및 $19.5{\sim}93.4%$로 조사구의 지질과산화에 대한 억제 효과가 높게 나타내었고 첨가수준 0.4 ${\mu}g/mL$와 0.8 ${\mu}g/mL$ 농도에서는 비조사 시료에 비해 유의적으로 높은 활성을 나타내었다(p<0.05). Comet assay를 이용한 EtOAc 분획물의DNA 방어효과 시험에서 생쥐 림프구에서 방사선에 의한 DNA 외가닥 절단 정도를 측정한 결과 TM 값은 정상대조군에서 $3.85({\pm}0.15)$이었고 방사선 조사군의 경우 $22.6({\pm}0.38)$로 증가되었다. 감마선 조사시킨 시료처리군의 경우 10 ${\mu}g/mL$에서 각각 $15.6({\pm}0.28)$, $12.01({\pm}0.31)$로서 DNA의 외가닥 절단에 대한 유의한 억제효과를 관찰할 수 있었다(p<0.05). 이러한 결과는 소목의 구성성분 중 brazilein, brazilin, gallic acid, quercetin 같은 다양한 페놀성 화합물과 플라보노이드의 배당체들이 방사선 조사에 의해 이탈됨에 따른 페놀 함량이 증가하여 항산화 활성도 향상됨을 확인할 수 있었다. 따라서 소목 추출물에 감마선 조사기술을 이용한다면 항산화 활성의 향상과 색택 개선 등 산업적으로 활용도가 높은 천연소재를 제조할 수 있으리라 사료된다. Caesalpinia sappan L. is an indeciduous tree distributed in China, India, Miyanmar and Vietnam. Its heartwood has long been used in oriental folk medicines to treat diseases. In this study, antioxidative activities of Caesalpinia sappan L. and the effect of gamma irradiation on its chemical and biological properties were investigated. The ethyl acetate fraction (EtOAc fr.) of Caesalpinia sappan L. was irradiated with 100 kGy of gamma ray. The dark red color of EtOAc fr. was significantly (p<0.05) removed by irradiation (Hunter L and b values increased and a value decreased). The total phenolic content of EtOAc fr. was 865 mg/g and it was increased to 1195 mg/g by gamma irradiation. DPPH radical and superoxide anion radical scavenging activities and lipid peroxidation inhibitory activity of EtOAc fr. were very high and its activities were also increased by gamma irradiation. EtOAc fr. also inhibited the irradiation-induced DNA damage of lymphocyte as determined by comet assay. In conclusion, EtOAc fr. of Caesalpinia sappan L. extract showed high antioxidative activities in vitro. Furthermore, gamma irradiation on EtOAc fr. ameliorated the color and antioxidative properties. Therefore, it can be suggested that Caesalpinia sappan L. may be a good material for antioxidant function and gamma irradiation may be applied for the improvement of chemical and biological properties of Caesalpinia sappan L.
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소음성 난청 진전도 측정을 위한 청력측정법에 관한 연구
권형준,이성태,배명진,Kwon, Hyung-Jun,Lee, Sung-Tae,Bae, Myung-Jin 한국음향학회 2010 韓國音響學會誌 Vol.29 No.3
최근 노화현상 외에도 소음으로 인한 청력저하를 호소하는 사례가 늘어나고 있다. 특히 멀티미디어의 보급과 휴대용 정보기기의 발달로 지속적인 소음에 장시간 노출되어 청각 세포의 손상이 발생하여 청력 손실이 발생하는 소음성 난청 인구가 증가하고 있는 실정이다. 현재 병원에서 실시하고 있는 순음청력검사는 8000 Hz까지의 주파수대역을 수동으로 조절하며 검사하므로 8,000 Hz 이상의 확장 고주파수에서도 손실을 가져오는 소음성 난청의 경우 회화 영역에 직접적인 영향을 미치지 않아 조기에 청력저하를 파악하여 예방하기에는 부적합한 단점이 있다. 본 논문에서는 12,000 Hz∼20,000 Hz 고주파 대역을 이용하여 소음성 난청을 조기에 파악하여 예방하기 위한 청력측정법을 제안하였다. 휴대용 정보기기를 통해 이어폰을 많이 사용하는20대 남녀 50명을 대상으로 제안한 측정법으로 청력을 측정한 결과 36 %가 소음으로 인한 청력 저하를 보였다. 그 중 2 %는 청력의 손실정도가 심각함을 보였다. Lowering of auditory caused by noise is increased, these days. Especially, people who have noise induced hearing loss by permanent exposure to noise are increased according to spread out of multimedia and improvement of information equipment. The pure tone audiometry used in the hospital presently inspect auditory manually up to 8,000 Hz bandwidth. So the case of noise induced hearing loss which suffered from extended high frequency over 8,000 Hz, there is a problem to prevent hearing loss by precognition. In this paper, we proposed a method to prevent noise induced hearing loss by using extended high frequency bandwidth from 12,000 Hz to 20,000 Hz. We have got a experimental result to fifty of twenties who are often used to earphones through portable equipment. As a result, 36% of twenties show lowering of auditory caused by noise and 2% of them shows severe loss of hearing.
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권형준(Hyung Jun Kwon),허순철(Soon Chul Huh) 한국헌법학회 2004 憲法學硏究 Vol.10 No.3
E-mail is a convenient and financially beneficial tool In the work-place. Although businesses that take advantage of e-mail have experienced many benefits. these same businesses also face a number of disadvantages. One such disadvantage is the legal liability that employers may face for the e-mall-related actions of their employees Recognizing these problems. employers are now using surveillance software. known as 'spyware' that can capture every keystroke a user types at a computer. or take screen shots at regular intervals of everything a computer user does Including Web-based e-mail activity Employers give three main reasons for electronically monitoring employee e-mail use minimizing liability. avoiding reduction In employee productivity. and protecting company assets There is a fundamental difference between company-controlled. company-provided e-mail accounts and personal. web-based accounts. each system has a different host or origrnator In a company system. the employer controls and usually hosts the system on a company server. In a pelsonal e-mail system. an independent provider. such as Yahoo 01 Hotmall. stores the e-mall on its server. In response to the lack of privacy afforded company e-mail accounts. many employees choose to conduct their personal affairs via web-based. personal e-mall accounts that are typically available through Internet access provided by the employer But web-based accounts may not isolate an employer from liability. most companies In the US, therefore, seek the ability to mom tor web-based, per?sonal e-mall accounts as well The U,S, courts examining common law privacy claims related to the e-mail monitoring have generally sided with employers, holding that there is no reasonable expectation of privacy in a company-maintained, proprietary e-mail account, These decisions are based on three primary rationales, First, the courts have focused on the fact that e-mails are sent and received via the company, proprietary e-mail system, Employees are using the company's property while on company time Using a computer and server that belong to another tends to decrease one's expectation of privacy in the use of such devices Second, the courts point to the fact that e-malls sent via company e-mail systems are open to forwarding by a third party which diminishes any expectation of privacy with regard to e-malls Even in cases where companies allowed employees to create folders for the e-mail or utilize password protection for their accounts, the courts still hold that this does not create a reasonable expectation of privacy, Finally, the courts turn to the level of offensiveness that the intrusion would impose on a reasonable person The courts have suggested several reasons why employee suits would not pass this hurdle, The courts take into account an employer's Justifications and Interests in monitoring, and have often determined that the legitimate business Interests of a company achieved by monitoring far outweigh an employee's privacy concerns Such legitimate business interests Include avoiding workplace discrimination or investigating theft or illegal activity The courts also stress the fact that all computers used to store, send, and receive the e-malls are owned by the employer, and are thus company property These factors have led courts to conclude that an employer monitoring employee e-mall messages on a proprietary company system, for legitimate purposes, does not rise to the level of being highly offensive to a reasonable person The courts and the legislatures in the U S are one step belimd in interpreting and creating laws that will adequately reflect the interaction between computer technology and society However, the legal interpretation or protection should be distmguished between company-controlled, company-provided e-mail accounts and personal. web-based accounts because there is a fundamental difference m technology, the web-based account e-mails are not automatically
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공법 : 거주(居住),이전(移轉)의 자유(自由)에 관한 연구(硏究)
권형준 ( Hyung Jun Kwon ) 한양대학교 법학연구소 2008 법학논총 Vol.25 No.3
Since the 19th century the right to move has been recognized as a fundamental constitutional right. But It was not included explicitly in the text of the constitution of 1787 in USA or the Declaration des droits de 1789 in France. It has been suggested that it was believed to be so basic a right that it need not be expressed in the text. The article 111 of Weimar constitution of 1919 explicitly recognized it for the first time. The Article 14 of the Constitution lay down the freedom of residence and the right to move; "All citizens shall enjoy freedom of residence and the right to move at will." The Article 14 of the Constitution protect the right to choose and change residency in Korea, the right to travel in Korean territory, the right to travel abroad and freedom of emigration(secession from Korean nationality). The freedom of residence and the right to move at will of all citizens may be restricted by Act only when necessary for national security, the maintenance of law and order or for public welfare. Even when such restriction is imposed, no essential aspect of the freedom or right shall be violated(Article 37 section 2).
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