• Title/Summary/Keyword: atria

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Simulation Study of Smoke Control Accordance with Zoning in the Atrium Space of High-rise Buildings (초고층 건물 아트리움 공간에서의 제연구획에 따른 시뮬레이션 연구)

  • Ryu, Hyungkyou;Bae, Sanghwan;Lee, Byungseok
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.7
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    • pp.335-342
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    • 2014
  • The big issue in fire and life safety protection in atriums is that hot smoke can spread vertically via the atrium openings, and impact atrium floors remote from the fire. Three different strategies to provide fire and life safety protection for atrium space were evaluated in this study, using the FDS model. Strategy A is the atrium protection approach addressed in the Korean Building Fire Protection Code, where atria are required to be enclosed with fire shutters from the $2^{nd}$ floor to the atrium top, and the ground floor is allowed to open to the atrium; in this case, no smoke control is required. Strategy B is the atrium protection approach, with smoke control provided in accordance with NFPA 92B; in this case, no atrium floor is enclosed. Strategy C is the atrium protection approach, in which some of the upper atrium floors are enclosed (the case of the top atrium floor being enclosed is evaluated in this study), and atrium smoke control is also provided to protect the lower atrium floors.

A Study on Design Tendencies in Office Buildings of Public Institutions after Reinforcement of the Building Energy Performance Criteria in Korea (건물에너지성능기준 강화 이후 국내공공기관 업무용 건축물의 디자인경향)

  • Lee, Ah-Young
    • KIEAE Journal
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    • v.11 no.6
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    • pp.139-149
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    • 2011
  • This study focuses on design tendencies in office buildings of public institutions after tightening up Korea's building energy performance criteria. Important office design criteria and recommendations pay attention to the issues such as building orientation, greening buildings, building form, space and envelop by intensifying building energy performance related laws, government guidelines and evaluation systems. The design tendencies explored in this research are as follows. Office buildings mainly face south and have various types of indoor and roof green spaces not for ecological reasons but for the rest. Building depth becomes thinner and atria are inserted into office buildings to improve daylighting and natural ventilation. Building cores are located on north or west and east sides acting as buffer spaces to reduce heat loss and to block solar radiation. Office building envelop design includes various creative ideas to control or utilize solar energy as like three dimensional or double structured skin and window size variation to cope with the intensity of solar radiation. Further, solar energy generation systems are integrated with building component such as roofs, sun screens and windows. This study demonstrates that government's reinforcement of the building energy performance criteria drives the change in design methods and approach.

Thermal Property Measurement of Swine Atrium

  • Oh, Jung-Hwan;Kim, Jee-Hyun
    • Journal of Biomedical Engineering Research
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    • v.29 no.5
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    • pp.343-347
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    • 2008
  • Thermal conductivity, thermal diffusivity were measured in the atrium of a swine heart. Radiofrequency (RF) catheter ablation in an atrium has rapidly emerged at the treatment of symptomatic reentrant arrhythmia associated with accessory pathway or Atrioventricular (AV) node conduction. The thermal properties of an atrium are definitely necessary for these treatments because, in thermal treatments, conductivity and diffusivity are significant factors in the relationship between the applied RF power and the resulting atrium temperature rise. Thermal properties were measured using a self-heated thermistor probe. Thermistor probes were inserted into the tissue of interest and were used to supply heat within the tissue as well as to monitor the temperature rise in the tissue. The measurements were performed at temperatures of 25, 37, $50^{\circ}C$. Atrium thermal conductivity ranged from 5.17$\pm$0.12 mW/cm$^{\circ}C$ at $25^{\circ}C$ to 5.33$\pm$0.08 mW/cm$^{\circ}C$ at $37^{\circ}C$. Atrium thermal diffusivity ranged from 0.00132$\pm$0.00007$cm^2$/sec at $25^{\circ}C$ to 0.00138$\pm$0.00003 $cm^2$/sec at $50^{\circ}C$. This paper also present the thermal property comparison of both chambers of a heart (ventricle and atria).

Pharmacological Actions of New Woohwangchungsimwon Liquid on Cardiovascular System (신우황청심원액의 심혈관계에 관한 약효연구)

  • 조태순;이선미;김낙두;허인회;안형수;박대규
    • Biomolecules & Therapeutics
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    • v.5 no.4
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    • pp.390-401
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    • 1997
  • In order to investigate the pharmacological properties of New Woohwangchungsimwon Liquid (NCL), effects of Woohwangchungsimwon Liquid (CL) and NCL were compared. In isolated rat aorta, NCL and CL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) without regard to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxation of NCL and CL. NCL and CL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NCL and CL significantly decreased heart rate. NCL and CL, at high doses, had a negative inotropic effect that was a decrease of LVDP and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NCL and CL had no effects on parameters of action potential at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NCL and CL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between two preparations.

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Congenital Heart Disease: a Pictorial Illustration of Putting Segmental Approach into Practice

  • Yeung, Tse Hang;Park, Eun-Ah;Lee, Ying Cheong;Yoo, Jin Young;Lui, Choi Yu
    • Investigative Magnetic Resonance Imaging
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    • v.19 no.4
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    • pp.205-211
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    • 2015
  • The human heart is a complex organ in which many complicated congenital defects may happen and some of them require surgical intervention. Due to the vast complexity of varied anatomical presentations, establishing an accurate and consistent nomenclature system is utmost important to facilitate effective communication among pediatric cardiologists, cardiothoracic surgeons and radiologists. The Van Praagh segmental approach to the complex congenital heart disease (CHD) was developed in the 1960s and has been used widely as the language for describing complex anatomy of CHD over the decades. It utilizes a systematic and sequential method to describe the cardiac segments and connections which in turn allows accurate, comprehensive and unambiguous description of CHD. It can also be applied to multiple imaging modalities such as echocardiogram, cardiac CT and MRI. The Van Praagh notation demonstrates a group of three letters, with each letter representative for a key embryologic region of cardiac anatomy: the atria, ventricles and great vessels. By using a 3-steps approach, we can evaluate complex CHD precisely and have no difficulties in communicating with other medial colleague. This pictorial essay revisits the logical steps of segmental approach, followed by a pictorial illustration of its application.

Hypotensive and Spasmolytic Activities of Crude Extract of Cyperus scariosus

  • Gilani, Anwar H.;Janbaz, K.H.;Zaman, M.;Lateef, A.;Tariq, S.R.;Ahmad, H.R.
    • Archives of Pharmacal Research
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    • v.17 no.3
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    • pp.145-149
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    • 1994
  • Intravenous administration of hydro-methanolic extract of Cyperus scariosus (3-10 mg/kg) produced hypotensive and bradcardiac effects. These effects remianed unaltered in atropinized animals indicating that cardiovascular effects of the plant extract are not medliated through activation of muscarinic receptors. In the in vitro studies, it suppressed the spontaneous contractions of guinea-pig paired atria, rat ulterus and rabbit jejunum in a concentration-dependent (0.1-1 mg/ml) manner. It also inhibited histanmine or acetylcholine-induced contractions of guinea-pig ieum indicating non-sepcific spasmolytic action. In rabbit aorta, it inhibited norepinephrine $(10\;mu{M)}$ as well as $K^+$ (80mM)-induced contractions at similar concentrations (0.1-1 mg/ml). These data indicate that cyperus scariosus contains $Ca^{2+}$ channel blocker-like constituent(s) which may explain hypotensive effect observed in vivo and the general spasmolytic activity of plant explain its folkloric use in diarrhoea.

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Projecting Performance of a Daylighting Source Based on Its Architectura Applications in the Open-Top Surface Structure (고심도 공간의 건축적 특성에 따른 자연집광 시스템의 조명원적 성능분석)

  • Kim, Gon;Kim, Jeong Tai
    • KIEAE Journal
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    • v.9 no.1
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    • pp.23-30
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    • 2009
  • A lightcourt design is typically used to address issues concerning aesthetics, feeling, and mood. From the view point of environmental aspect, as an ecological shaft space, it plays a key role in controlling inner quality. In particularly, the lightcourt concept allows the exploitation of daylighting by bring natural light into the center of the building, thus eliminating dark deep spaces. Additionally, the lightcourt shades the inner space in summer. The amount of light available at the base of the lightcourt depends on a number of factors; translucency of the top, reflectance and the geometry of the space. In this paper is to exemplify a lightcourt configuration with a sloped wall. It promises the maximized a sense of freedom and daylighting availability. It is a matter of course that the lightcourt with open-top plays a role as a light source for the adjacent space to the lightcourt. A series of lighting simulation provides performance data of daylighting with changing photometric factors. For the case that a skylight is not available, an electric lighting design with metal halide lamps has been established to create luminous ceiling. As expected, a sloped lightcourt with open-top exposes its superiority of daylighting source. Ancillary considerations to enhance of daylighting potential for the adjacent space have been issued with performance data.

Characteristics of Atrial Natriuretic Peptide Release in Renal Hypertensive Rats (신성 고혈압 백서 심방의 심방이뇨 호르몬분비 특성)

  • Cho, Kyung-Woo;Seul, Kyung-Hwan;Kim, Suhn-Hee;Seul, Kyung-Mee;Koh, Gou-Young
    • The Korean Journal of Physiology
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    • v.24 no.2
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    • pp.261-268
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    • 1990
  • It has long been suggested that the cardiac atrium is a low pressure volume receptor controlling body fluid volume and blood pressure. Recently, the cardiac atrium has been found to contain a family of powerful peptides. To clarify the relationship between high blood pressure and the biologically active atrial peptides, experiments were done to define the characteristics of atrial natriuretic peptide secretion in the isolated perfused atria of renal hypertensive rats. Higher concentrations of plasma atrial natriuretic peptide and renin activity were observed in the two-kidney, one clip hypertensive rat compared to the normotensive rat. Atrial volume changes in response to pressure elevations were attenuated in hypertensive rats compared to normotensive rats. Incremental response to atrial volume changes in ANP secretion was accentuated in hypertensive rats. These date suggest that the accentuated atrial natriuretic peptide response to volume changes of hypertensive rats may be a physiological or pathphysiological adaptation to the high blood pressure and may be, at least in part, responsible for the elevated levels of plasma atrial natriuretic peptide observed in hypertensive rats.

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Right to Left Atrial Septum Defect Compounded with Patent Ductus Arteriosus in a Maltese Dog

  • Ahn, Sung-Taek;Kim, Myung-Jun;Yoon, Won-Kyoung;Suh, Sang-il;Hyun, Changbaig
    • Journal of Veterinary Clinics
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    • v.34 no.2
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    • pp.90-93
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    • 2017
  • A nine-month-old intact female Maltese dog (body weight: 1.5 kg) presented with frequent syncopal episodes (1-2/day), exercise intolerance, and dyspnea. Cardiomegaly with marked dilation of right and left atria along with ascites was indicated on radiography. Tricuspid regurgitant jets (4.36 m/s), pulmonary regurgitant jets (3.4 m/s), left-to-right shunting flow at the ductus arteriosus, and an atrial septal defect were observed on echocardiography. A bubble study with agitated saline found right-to-left shunting at the interatrial septum. Based on diagnostic studies, the dog was diagnosed with right-to-left atrial septum defect (ASD) compounded with patent ductus arteriosus (PDA). The treatment was directed to reduce the pulmonary hypertension, improve cardiac performance, and lower fluid retention. Despite medical treatment for 2 months, the dog died of sudden cardiac arrest. Herein, we describe a very rare case of right-to-left ASD compounded with PDA.

Pharmacological Actions of New Wonbang Woohwangchungsimwon Liquid on Cardiovascular System (신원방우황청심원액의 심혈관계에 관한 약효)

  • 조태순;이선미;김낙두;허인회;안형수;권광일;박석기;심상호;신대희
    • Biomolecules & Therapeutics
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    • v.7 no.1
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    • pp.66-78
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    • 1999
  • In order to investigate the pharmacological properties of New Wonbang Woohwangchungsimwon Liquid (NSCL), effects of Wonbang Woohwangchungsimwon Liquid (SCL) and NSCL were compared. In isolated rat aorta, NSCL and SCL showed the relaxation of blood vessels in maximum contractile response to phenylephrine (10$^{-6}$ M) regardless to intact endothelium or denuded rings of the rat aorta. Furthermore, the presences of the inhibitor of NO synthase and guanylate cyclase did not affect the relaxing effect of NSCL and SCL. NSCL and SCL inhibited the vascular contractions induced by acetylcholine, prostaglandin endoperoxide or peroxide in a dose-dependent manner. In conscious spontaneously hypertensive rats (SHRs), NSCL and SCL significantly decreased heart rate. NSCL and SCL, at high doses, had a negative inotropic effect that was a decrease of left ventricular developed pressure and (-dp/dt)/(+dp/dt) in the isolated perfused rat hearts, and also decreased the contractile force and heart rate in the isolated rat right atria. In excised guinea-pig papillary muscle, NSCL and SCL had no effects on parameters of action potential such as resting membrane potential, action potential amplitude, APD$_{90}$ and V$_{max}$ at low doses, whereas inhibited the cardiac contractility at high doses. These results suggested that NSCL and SCL have weak cardiovascular effects with relaxation of blood vessels and decrease of heart rate, and that this effect is no significant differences between cardiovascular effects of two preparations.s.

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