• Journal of Preventive Medicine and Public Health
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• 제45권6호
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• pp.344-352
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• 2012

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety.

• Journal of the Korean Wood Science and Technology
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• 제33권1호통권129호
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• pp.1-6
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• 2005

본 연구는 국내에 서식하는 일본흰개미(Reticulitermes speratus)의 생리적 특성에 관한 기초연구로서 흰개미의 커뮤니케이션 수단인 페로몬을 후각수용기로 이동시키는 odorant-binding proteins (OBPs)의 발현 양상을 조사하기 위해서 수행되었다. 경남 진주에서 채집된 일개미와 병정개미로부터 더듬이와 다리를 각각 떼어낸 후 OBP가 존재하는지 확인하기 위하여 RT-PCR을 수행하였다. 일개미의 경우 OBP-1의 발현은 더듬이와 다리에서 모두 관찰되었으며, OBP-2와 OBP-3의 발현은 오직 더듬이에서만 관찰할 수 있었다. 병정개미의 경우 OBP-1의 발현은 일개미에서와 마찬가지로 더듬이와 다리 모두에서 관찰할 수 있었으나, OBP-2가 관찰되지 않았으며, 일개미의 더듬이에서만 관찰되었던 OBP-3의 발현을 병정개미에서는 더듬이와 다리 모두에서 볼 수 있었다. 일개미와 병정개미에서 OBP 발현 양상의 차이는 그들의 역할에 따른 분화적 특이성에 기인한 것으로 생각된다.

• Toxicological Research
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• 제33권4호
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• pp.333-342
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• 2017

Ethyl formate, a volatile solvent, has insecticidal and fungicidal properties and is suggested as a potential fumigant for stored crop and fruit. Its primary contact route is through the respiratory tract; however, reliable repeated toxicological studies focusing on the inhalation route have not been published to date. Therefore, the present study was conducted to investigate the safety of a 90-day repeated inhalation exposure in rats. Forty male and 40 female rats were exposed to ethyl formate vapor via inhalation at concentrations of 0, 66, 330, and 1,320 ppm for 6 hr/day, 5 days a week for 13 weeks. Clinical signs, body weights, food consumption, urinalysis, hematologic parameters, serum chemistry measurements, organ weights, necropsy, and histopathological findings were compared between the control and ethyl formate-exposed groups. Locomotor activity decreased during exposure and recovered afterward in male and female rats exposed to 1,320 ppm ethyl formate. Body weight and food consumption continuously decreased in both sexes exposed to 1,320 ppm ethyl formate from week 1 or 3 compared with the control values. The increases in adrenal weight and decreases in thymus weight were noted in both sexes exposed to ethyl formate at 1,320 ppm. Degeneration, squamous metaplasia of olfactory epithelium in the nasopharyngeal tissue, or both were noted in the male and female rats at 1,320 ppm and female rats at 330 ppm ethyl formate. Taken together, our results indicate that ethyl formate-induced changes were not observed in male and female rats at 330 and 66 ppm, respectively. This indicates that exposure to ethyl formate at concentrations below 66 ppm for 90 days is relatively safe in rats. This is the first report of a full-scale repeated inhalation toxicity assessment in rats and could contribute to controlling occupational environmental hazards related to ethyl formate.

• 한국식품과학회지
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• 제38권1호
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• pp.16-21
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• 2006

본 연구는 야자유를 190, $220^{\circ}C$에서 24시간 가열한 후 6개의 MOS로 구성된 전자코로 산패정도를 판별하였다. 주성분분석 결과 제1주성분 값이 열처리 시간에 따라 +0.952에서 0.325로 감소하였다. 가열 온도를 높임에 따라 야자유의 산패정도도 증가하였다. 또 다른 방법에 하나로 GC를 바탕으로 한 SAW센서가 부착된 전자코를 사용한 결과 후각이미지가 뚜렷하게 차이가 나는 것을 보여주었다. 160, $220^{\circ}C$에서 가열한 야자유로부터 휘발 성분에 대한 GC peak의 수와 넓이가 가열온도와 가열 처리 시간에 따라 증가함을 보여주었다. 이러한 방법은 신속하면서도 곧바로 알기 쉽게 데이터를 이미지화함으로써 가열 처리된 야자유의 휘발성분을 전자코로 신속하고 간편하게 분석하여 가열 처리 정도가 예측 가능하였다.

• Journal of Korean Neurosurgical Society
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• 제30권sup2호
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• pp.197-202
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• 2001

Objective : The purpose of this study is to evaluate and compare surgical results of pterional(fronto-temporal) approach and interhemispheric approach for the high positioned anterior communicating artery aneurysm with our surgical experience. Methods : During the period between May 1990 and May 2001, 263 anterior communicating aneurysms were treated at the department of neurosurgery of Dong-A university hospital. Among them, 175 patients were operated by same operator. Thirty six out of the 175 cases were high positioned anterior communicating artery aneurysms located more than 15mm above the anterior clinoid process. Results : Pterional approaches were applied in 32 cases and interhemispheric approaches were applied in 4 cases of total 36 cases of the high positioned anterior communicating artery aneurysms. The 32 cases of pterional approach resulted in Good Recovery 20/32(63%), Moderate Disability 6/32(19%), Severe Disability 4/32(12%) and Dead 2/32(6%), and 4 cases of interhemispheric approach resulted in GR 3/4(75%) and MD 1/4(25%). Relatively, pterional approach showed poorer result on high positioned anterior communicating artery aneurysm located more than 19mm above the anterior clinoid process with GR 5/13(39%), MD 3/13(23%), SD 3/13(23%) and Dead 2/13(15%). Conclusion : Interhemispheric approach is preferable to pterional approach for certain cases of high positioned anterior communicating artery aneurysm located more than 19 mm above the anterior clinoid process because it provides adequate orientation to the regional anatomy, less retraction of frontal lobe and preservation of the olfactory tract and gyrus rectus without any surgical complications.

• 정보관리연구
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• 제41권4호
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• pp.41-67
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• 2010

군사적 목적으로 시작된 증강현실 기술은 2000년대로 넘어오면서 무선인터넷과 위치기반기술 등의 등장으로 기술의 변혁기를 맞이하고 있다. 특히 현실에 불러오는 가상의 정보가 시각 분야에서 청각, 촉각, 후각 등 다른 감각으로 확장할 수 있는 가능성 때문에 인간의 지각을 풍요롭게 하는 매체의 일환으로 주목을 받고 있다. 본 연구에서는 도서관에서 활용 가능한 증강현실기반의 2D 바코드를 활용한 양방향 정보서비스 시스템에 대한 설계와 서비스 방법에 대하여 제안하였다. 이를 위하여 증강현실에 대한 기술적 배경과 응용분야를 분석하고 도서관의 정보서비스에 적용할 수 있는 방법에 대하여 알아보았다. 특히 유비쿼터스 환경에서 이용자의 요구 및 편의성에 기반을 둔 정보서비스의 구현을 위한 에코서비스로서 2D 바코드를 활용한 정보서비스를 제안하였다.

• 한국콘텐츠학회논문지
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• 제9권9호
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• pp.191-198
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• 2009

21세기는 기술 발달로 인해 소재의 다양화와 학문적 연계를 통한 디자인 결합은 우리의 삶에 있어 다양한 욕구의 변화를 가져왔으며, 그로인해 시각적인 관심과 함께 기능적 역할의 조화로 자기 개성에 맞는 디자인 개발이 관심의 대상이 되고 있다. 최근 다양한 소재를 이용한 디자인 개발이 추세이고 이러한 디자인 경향은 개인의 감성과 취향을 존중하고 있으며, 이에 따라 다변화 되고 있다. 생활수준의 향상으로 건강과 개성에 대한 관심과 향기에 대한 관심이 높아지고 향(香)은 기억이나 감성 등 개인의 취향과 개성에 맞게 다양한 형태로 개발되고 있다. 이에 본 연구자는 향기 나는 소재를 사용하여 기계적인 특성과 미적 요소를 가미한 소재를 가지고 소비자의 감성적 욕구에 맞게 장신구 분야에 적용하고 시각적 디자인에 후각을 접목하면서 여성의 보조적 디자인에서 벗어나 남성만의 개성과 감성을 표현 할 수 있는 남성 신변장신구에 대한 활용 방안을 제시 하고자 한다.

• Safety and Health at Work
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• 제2권4호
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• pp.355-364
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• 2011

Objectives: Though sulfur dioxide (SO2) is used widely at workplaces, itseffects on humans are not known. Thresholds are reportedwithout reference to gender or age and occupational exposure limits are basedon effects on lung functioning, although localized effects in the upper airways can be expected. This study's aim is to determine thresholds with respect to age and gender and suggests a new approach to risk assessment using breathing reflexes presumably triggered by trigeminal receptors in the upper airways. Methods: Odor thresholds were determined by the ascending method of limits in groups stratified by age and gender. Subjects rated intensities of different olfactory and trigeminal perceptions at different concentrations of $SO_2$. During the presentation of the concentrations, breathing movements were measured by respiratory inductive plethysmography. Results: Neither age nor gender effects were observed for odor threshold. Only ratings of nasal irritation were influenced bygender. A benchmark dose analysis on relative respiratory depth revealed a 10%-deviation from baseline at about 25.27 mg/$m^3$. Conclusion: The proposed new approach to risk assessment appearsto be sustainable. We discuss whether a 10%-deviation of breathingdepth is relevant.

• 대한통합의학회지
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• 제9권3호
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• pp.9-18
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• 2021

Purpose : In this study, we applied a computerized cognitive rehabilitation program (CoTras-C) for children with cerebral palsy. Research was conducted to investigate the impact of upper limb function, sensory function, and activities of daily living. Methods : The study period lasted 10 weeks from October 2019 to December 2019. The study subjects were 12 subjects according to the selection criteria, and a computerized cognitive rehabilitation program (CoTras-C) was conducted twice a week for 30 minutes before and after the application of basic occupational therapy. Results : As a result of the computerized cognitive rehabilitation program, scores of upper limb function (QUEST), sensory function (SSP-2), and daily life activity (WeeFIM) were significantly improved (p>.05). From the result of examining the motor area, improvement in fine-motor function and protective extension through touch pad or controller operation was found. It also showed improvement in activities of daily living including motor and activities of daily living including social cognition. In the sensory function evaluation, it was not significant in movement sensitivity. Significant differences were shown in the items excluding olfactory/taste sensitivity. Conclusion : The application of the computerized cognitive rehabilitation program (CoTras-C) showed significant results in upper limb function, sensory function, and daily life activities of children with brain lesions. Based on these results, future studies need to generalize the study by expanding the age or population of children with brain lesions, or by expanding the diversity of diseases and environments.

• Journal of Veterinary Science
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• 제22권3호
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• pp.36.1-36.12
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• 2021

Background: Mouse hepatitis virus (MHV) A59 is a highly infectious pathogen and starts in the respiratory tract and progresses to systemic infection in laboratory mice. The complement system is an important part of the host immune response to viral infection. It is not clear the role of the classical complement pathway in MHV infection. Objectives: The purpose of this study was to determine the importance of the classical pathway in coronavirus pathogenesis by comparing C1qa KO mice and wild-type mice. Methods: We generated a C1qa KO mouse using CRISPR/Cas9 technology and compared the susceptibility to MHV A59 infection between C1qa KO and wild-type mice. Histopathological and immunohistochemical changes, viral loads, and chemokine expressions in both mice were measured. Results: MHV A59-infected C1qa KO mice showed severe histopathological changes, such as hepatocellular necrosis and interstitial pneumonia, compared to MHV A59-infected wild-type mice. Virus copy numbers in the olfactory bulb, liver, and lungs of C1qa KO mice were significantly higher than those of wild-type mice. The increase in viral copy numbers in C1qa KO mice was consistent with the histopathologic changes in organs. These results indicate that C1qa deficiency enhances susceptibility to MHV A59 systemic infection in mice. In addition, this enhanced susceptibility effect is associated with dramatic elevations in spleen IFN-γ, MIP-1 α, and MCP-1 in C1qa KO mice. Conclusions: These data suggest that C1qa deficiency enhances susceptibility to MHV A59 systemic infection, and activation of the classical complement pathway may be important for protecting the host against MHV A59 infection.