• Advances in Traditional Medicine
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• 제7권1호
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• pp.11-25
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• 2007

Bronchial asthma is a major public health problem worldwide and the morbidity and mortality of asthma have increased in last few decades. There is high prevalence of usage of alternative traditional system of medicines for the treatment of asthma. Large numbers of medicinal plant preparations have been reported to possess anti-asthmatic effects. Plant cells are now considered to be the chemical factories synthesizing a large variety of chemical compounds. Further, Ayurvedic system of medicine has an elaborate description of asthma from the earliest times describing it as 'Shwasa' meaning disease pertaining to breathing. This review classifies the antiasthmatics herbs based on the possible mechanism of action reported. Thus, these plants can be used to obtain a polyherbal formulation which contains various herbs acting at particular sites of the pathophysiological cascade of asthma for prophylaxis as well as for the treatment of asthma.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.649-656
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• 2004

Hypersonic wind tunnel test of the rectangular variable geometry intake is performed. For realization of a Precooled turbojet engine, development of a hypersonic ramjet engine is planned. To investigate performance of the intake of the hypersonic ramjet engine, wind tunnel test is done with freestream Mach number of 5.1. The total pressure recovery was 18 % with 12.9 % of ramp bleed. Several reasons for low total pressure recovery are shown. Supersonic internal compression is not enough. Then, the throat Mach number is high (M2.61) and total pressure losses at the terminal shock is large. Supersonic flow at the throat and position of the terminal shock is sensitive to a difference of the second ramp's throat height and the third ramp's throat height. Flow separations at the second ramp's trailing edge and the third ramp's leading edge are seen those could result in the trigger of unstart. The seal mechanism between the ramps and the sidewalls is important.

• 한국화재소방학회논문지
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• 제21권2호
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• pp.64-73
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• 2007

호흡기 내에서 유해물질의 체내흡수 및 방어특성은 영역별로 다르며 흡입연기의 장 단기 인체 유해성은 연기의 호흡기 내 침착위치 및 침착밀도와 밀접한 관계를 가지고 있다. 이 연구에서는 미소부피 위치 추적법을 이용한 입자침착율 계산 기법을 사용하여 휴식 및 가벼운 운동에 해당하는 호흡조건별로 또한 구강 및 비강 호흡별로 각 입자크기에 대하여 호흡기 각 영역별로 단위 면적당 침착분율 등 침착 특성을 구하였다. 이 결과는 연기에 흡착된 유해물질의 체내 흡수량 산정 등에 이용되어 연기의 인체 유해성 판정에 도움을 줄 수 있을 것으로 판단된다.

• 한국초등과학교육학회지:초등과학교육
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• 제19권2호
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• pp.57-74
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• 2000

Students' concepts of scientific phenomena have become a point of focus in science education research. This study investigated into developmental process and mechanism of the students' respiration concept through a cross-age study. This study utilized the 1st, 3rd, 6th grade elementary students to find out changes in student's understanding of the concept of respiration. The 1st and 3rd grade level students were interviewed what the respiration mean and whether each of living things respires, etc. The 6th grade students were interviewed and tested. Respiration is a word that students come across often in everyday life. It was found that they were more likely to associate respiration with its more common concept of breathing or gas exchange as opposed to its more scientific definition as the process in which nutrients are oxidized to provide energy. This trend didn't improve as they advanced grade. This is an indication that the knowledge system of student is split into a generic knowledge system and scientific knowledge system. Understanding of concept increased and differentiated across grade levels but that understanding was limited. They overcome their tendency to base their understanding of respiration on their understanding of human phenomena and learn to integrate their understanding of biological phenomena through a one organ - one role type of logic. They also intuitively explain everything based on their own experience.

• 한국추진공학회지
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• 제10권2호
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• pp.115-128
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• 2006

스크램제트 추진기술에 대한 최근 개발동향과 주요기술을 분석하였다. 스크램제트엔진은 지난 10여년간 급속한 기술 발전으로 지상시험에서 비행시험 단계에 접어들고 있으며, 수년 내 실용시험을 목표로 활발하게 연구개발 중이다. 광범위한 비행 마하수를 만족하는 이중연소램제트와 이중모드램제트 형태의 엔진은 각각 군용과 민수용으로 개발되고 있으며, 복합엔진은 차세대 우주발사체의 대안으로 개발되고 있다. 엔진 작동 특성의 미케니즘에 대한 정확한 이해와 이에 상응되는 기술, 흡열연료 및 CSiC 복합재료를 사용한 내열 문제 해결, 가변 흡입구와 노즐을 이용한 안정된 추진력 구현을 목전에 두고 있다.

• Journal of Oral Medicine and Pain
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• 제43권3호
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• pp.61-69
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• 2018

Obstructive sleep apnea (OSA) is a relatively common, but greatly underdiagnosed sleep-related breathing disorder, characterized by recurrent collapse of the upper airway during sleep. OSA has been associated with a variety of cardiometabolic disease, such as hypertension, coronary artery disease, cardiac arrhythmia, cerebrovascular disease and metabolic dysfunction. Neurocognitive impairment, including excessive daytime sleepiness, increased risk of motor vehicle accidents, is also related to OSA. Sleep fragmentation and related arousals during sleep lead to intermittent hypoxia, sympathetic activation, oxidative stress, systemic inflammation and metabolic dysregulation which provide biological plausibility to this pathologic mechanism. Extensive studies demonstrated that OSA is a modifiable risk factor for the above mentioned diseases and oral appliances (OAs), although continuous positive air pressure (CPAP) is a first-line therapy of OSA, are not inferior to CPAP at least in mild OSA, and may be an alternative to CPAP in CPAP-intolerant subjects with OSA. The goal of this article is to provide a current knowledge of pathologic link between OSA and cardiovascular disease, focusing on intermittent hypoxia, sympathetic activation, oxidative stress and metabolic dysregulation. Then, previous epidemiologic studies will be reviewed to understand the causal relationship between OSA and cardiovascular disease. Finally, the effects of OAs will be updated via recent metaanalyses compared to CPAP.

• 대한후두음성언어의학회지
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• 제26권1호
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• pp.25-33
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• 2015

Background and Objectives:The objective of this study was to investigate the features of post-thyroidectomy subjective voice disorder by Voice Handicap Index (VHI) and Voice Symptom Scale (VOISS) through aerodynamic analysis and to investigate the appropriate voice therapy intervention. Materials and Methods:Twenty post-thyroidectomy patients who had no recurrent laryngeal nerve paralysis through laryngeal stroboscopy were enrolled for this study. Acoustic and aerodynamic evaluations were performed before operation, 2 weeks and 3 months after operation. Subjective voice evaluation was performed by VHI and VOISS. Aerodynamic evaluation was compared and analysed by maximum phonation time(MPT), phonation threshold pressure(PTP), mean air flow rate(MFR), etc. Subjective voice evaluation was surveyed through VHI and VOISS. To evaluate patients' symptoms related to functional voice disorder, scores on physical domain in VHI and VOISS were selected to be compared for each session. Results: The 10 out of 20 participants who complained of voice symptoms had no significant difference with pre-operation in acoustic evaluation, but all showed higher scores on 2 weeks and 3 months after operation compared to pre-operation, in VHI-physical domain and selected questionnaires in VOISS. They reduced MPT and increased PTP value simultaneously. Laryngeal massage and breathing training were simultaneously treated to them, 5 participants resulting in improvement in MPT and PTP compared to pre-treatment. Conclusion:Patients who complained voice change with no organic damage after thyroidectomy were all shown to have reduced MPT and increased PTP in some by aerodynamic evaluations. Reduced MPT may imply some problem in air flow beneath glottis. Increased PTP suggests much more effort in vocalization mechanism than pre-operation. Comparing aerodynamic evaluations in post-thyroidectomy may provide information on behavioral interventions. Additionally, study on laryngeal massage and breathing training simultaneously treated to patients with such voice disorder is needed to be conducted with larger number of participants.

• 대한치과의사협회지
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• 제49권4호
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• pp.219-226
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• 2011

Snoring and obstructive sleep apnea (OSA) are common sleep disordered breathing conditions. Habitual snoring is caused by a vibration of soft tissue of upper airway while breath in sleeping, and obstructive sleep apnea is caused by the repeated obstructions of airflow for a sleeping, specially airflow of pharynx. Researchers have shown that snoring is the most important symptom connected with the obstructive sleep apnea syndrome The treatment is directed toward improving the air flow by various surgical and nonsurgical methods. The current surgical procedures used are uvulopalatopharyngoplasty(UPPP), orthognathic surgery, nasal cavity surgery. Among the nonsurgical methods there are nasal continuous positive air pressure(CPAP), pharmacologic therapy. weight loss in obese patient, oral appliance(sleep splint). Sleep splint brings the mandible forward in order to increase upper airway volume and prevents total upper airway collapse during sleep. However, the precise mechanism of action is not yet completely understood, especially aerodynamic factor. The aim of this study evaluated the effect of conservative treatment of snoring and OSAS by sleep splint through measured aerodynamic change by an aerophone II. We measured a airflow, sound pressure level, duration, mean power from overall airflow by aerophone II mask. The results indicated that on a positive correlation between a decrease in maximum airflow rate and a decrease in maximum sound pressure level, on a negative correlation between a decrease in maximum airflow rate and a increase in duration.

• 대한소아치과학회지
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• 제27권4호
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• pp.517-523
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• 2000

비인강폐쇄는 연구개, 인두측벽 그리고 인두후벽간의 움직임이 서로 조화되어 구강과 비강을 나누어주는 괄약근 기전으로서 연하, 호흡 및 발음 등의 생리적 기능에 중요한 역할을 한다. 이 기능에 문제가 생긴 경우를 비인강폐쇄부전이라하며 그 원인으로는 (1) 연구개의 길이 및 움직임이상, (2) 비인두강의 해부학적 공간문제, (3) 인두후벽과 측벽의 기능이상 등이 있다. 본 연구는 구개열 환자의 측면두부방사선 사진을 통해 비인두강을 해부학적으로 분석하고 동시에 산출된 각 모음의 과비음 정도를 평가하여 비인강폐쇄부전과의 연관성을 비교해 본 것이며, 얻어진 결과는 다음과 같다. 1. 연구개 길이는 정상인에 비해 현저히 짧았다. 2. adequate ratio는 정상인에 비해 작게 나타났다. 3. adequate ratio가 감소함에 따라 모음 조음시 anatomic mVPI가 점차 증가하였다. 4. 각 모음 조음시 anatomic VPI는 과비음정도와 비례관계를 보였다. 5. 고모음(/u/, /i/)의 과비음정도가 저모음(/a/)에 비하여 크게 나타났다. 결론적으로, 구개열환자에서 측면두부방사선 사진은 비인강폐쇄부전의 진단 및 평가에 유용하게 사용될 수 있으며, 비인두강의 해부학적 구조는 산출되는 과비음정도와 밀접한 연관성이 있었다.

• Journal of Oral Medicine and Pain
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• 제33권2호
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• pp.205-218
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• 2008

수면과 통증과의 상호 작용은 여러 연구들에 의해 밝혀져 왔고 그 기전에 대해서는 현재도 다양한 연구들이 이루어지고 있으나 앞선 연구들은 대부분 류마티스질환이나 섬유근통과 같은 전신적 질환을 갖는 환자들을 대상으로 하고 있으며 측두하악질환을 포함한 안면통증 환자들을 대상으로 한 연구는 거의 없다. 본 연구에서는 구강내과, 턱관절 및 안면통증 클리닉에 내원한 229명의 측두하악장애 환자를 대상으로 수면설문 및 간이 수면검사를 시행하여 측두하악장애 환자에서의 통증양상과 수면과의 관계를 분석해 보았다. 1. PSQI설문에 의한 수면의 질 평가에서는 통증이 있는 측두하악장애 환자군이 통증이 없는 군에 비하여 수면의 질이 저하된 환자의 비율이 높게 나타났으며 수면의 질이 저하된 정도도 더 크게 나타났다. 특히 통증이 6개월 이상 지속된 만성 측두하악장애 환자에서는 뚜렷하게 수면의 질 저하가 나타났다. 2. ESS설문에 의한 주간졸리움증의 평가에서도 통증이 있는 측두하악장애 환자군이 통증이 없는 군에 비하여 주간졸리움증을 호소하는 환자의 비율이 더 높았으며 6개월이상 통증이 존재하는 만성 측두하악장애 환자군에서 더욱 높았으며 주간 졸리움증의 정도 또한 더 심하였다. 특히 통증이 있는 만성 측두하악장애 환자군 중에서 global PSQI가 5이상인 수면이 저하되어 있는 환자에서만 평균 ESS 수치가 10이상을 기록하여 주간졸리움증의 판단 기준에 해당하였다. 3. 통증의 강도에 따른 수면의 질과의 관련성이나 주간졸리움증과의 관련성의 결과는 상관관계가 없는 것으로 나타났다. 4. 수면관련 호흡장애를 검사하기 위한 간이수면검사기기인 ApnealinkTM를 사용하여 수면시 호흡상태를 측정한 결과 검사를 시행한 총 19명의 환자중 1명만이 수면무호흡저호흡지수(AHI)>5인 수면무호흡증을 나타내었다. 다른 만성통증질환과 마찬가지로 만성통증을 나타내는 측두하악장애 환자에서도 수면의 질이 저하되었으며 주간졸리움증이 심한 것으로 나타났다. 수면장애가 있는 경우 통증에 대한 역치를 낮추고 통증과 수면장애가 순환적인 상호작용을 일으켜 치료를 어렵게 하므로 측두하악질환을 진단하고 관리하는 데 있어 수면설문지를 이용한 수면 상태의 평가는 유용할 것으로 사료된다. 특히 치료가 장기화 되고 치료에 대한 반응이 적은 환자에게 있어서 수면장애에 대한 평가가 반드시 이루어져야 할 것으로 사료된다. 간이수면검사기기 또한 치과에서 진단하기 어려운 호흡관련 수면장애의 초기 검진 시 유용한 도구가 되리라 생각되는 바이다.