• Title/Summary/Keyword: active pressure

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Analysis of Researches on the Warming Therapy for Surgical Patients (수술 환자에게 적용한 가온요법 연구논문 분석)

  • Jun, Jum-Yi
    • Korean Journal of Adult Nursing
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    • v.22 no.3
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    • pp.260-270
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    • 2010
  • Purpose: The main question is systematic review of the published in Korea and foreign countries on warming therapy for surgical patients. Methods: The researchers searched at Medline, CINAHL, KERIS, Adult Nursing Association, Korean Society of Nursing Science, Korean Academy of fundamentals of Nursing, and National Assembly Library web site for the published on warming therapy for surgical patients from 1980 to 2008. Words for search were operation/surgery, warming, operation/surgery and warming. Studies were included randomized controlled trial, and there were no restrictions regarding operative phase and outcome measures. Results: 36 published researches that met the criteria were mostly published in foreign countries between 2000 and 2008 and focused on surgery with general anesthesia. Sample size ranged from 21 to 60 subjects, age range between 21 and 60 years of age. Thirty different warming therapies were reported, fifty-two different dependent variables. Outcome indicators included active external warming, intra-operative, and body temperature. 'Positive effects' and 'no effects' equaled. The most frequently reported 'positive effects' were body temperature, shivering, and acid-base balance. No effects were more likely to be heart rate, blood pressure, and hemodynamics. Conclusion: Many types of warming therapy, are reported in the literature with little information about the efficacy of each, many different dependant variables were studied. There were no consistent reports as to length of time used for warming procedures. Overall, the effects of warming therapy are inconsistent. And additional research must be down before any particular method of warming can be used with confidence as to its effectiveness. Attention must be made as to the research design, better measurement of the dependent variables. This review may serve as a base.

Development of Parallel Plate Avalanche Counter for heavy ion collision in radioactive ion beam

  • Wei, Xianglun;Guan, Fenhai;Yang, Herun;Wang, Yijie;Zhang, Junwei;Ma, Peng;Diao, Xinyue;Lu, Chengui;Li, Meng;Guan, Yuanfan;Duan, Limin;Hu, Rongjiang;Zhang, Xiuling;Xiao, Zhigang
    • Nuclear Engineering and Technology
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    • v.52 no.3
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    • pp.575-580
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    • 2020
  • We have developed a position-sensitive Parallel Plate Avalanche Counter (PPAC) to detect the fission fragments and reconstruct the fission reaction plane in the experiment of studying nuclear equation of state (nEOS) by means of heavy ion collision (HIC). This experiment put forward high requirements for the performances of PPAC, such as the time resolution, efficiency and position resolution. According to these requirements we designed the PPAC with an active area of 240 mm × 280 mm working at low gas pressure. The results show that time resolution could be less than 300 ps. Position resolution is consistent with the theoretical calculation about 1.35 mm. Detection efficiency could be approaching 100% gradually with the voltage increasing in different gas pressures. The performances of PPAC have also been verified in beam experiment. Each set of anode wires can be accurately separated in the position spectrum. In the beam experiment, we also got the back-to-back correlation of fission fragments which is one of the direct signals characterizing binary decay.

Water-Assisted Synthesis of Carbon Nanotubes at Low Temperature and Low Pressure (물을 첨가한 탄소나노튜브의 저온 저압 합성)

  • Kim, Young-Rae;Jeon, Hong-Jun;Lee, Nae-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.395-395
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    • 2008
  • Water-assisted synthesis of carbon nanotubes (CNTs) has been intensively studied in recent years, reporting that water vapor enhances the activity and lifetime of metal catalyst for the CNT growth. While most of these studies has been focused on the supergrowth of CNTs at high temperature, rarely has the similar approach been made for the CNT synthesis at low temperature. Since the metal catalyst are much less active at lower temperature, we expect that the addition of water vapor may increase the activity of catalyst more largely at lower temperature. We synthesized multi-walled CNTs at temperature as low as $360^{\circ}C$ by introducing water vapor during growth. The water addition caused CNTs to grow ~3 times faster. Moreover, the water-assisted growth prolonged the termination of CNT growth, implying the enhancement of catalyst lifetime. In general, a thinner catalyst layer is likely to produce smaller-diameter, longer CNTs. In a similar manner, the water vapor had a greater effect on the growth of CNTs for a smaller thickness of catalyst in this study. To figure out the role of process gases, CNTs were grown in the first stage and then exposed to each of process gases in the second stage. It was shown that water vapor and hydrogen did not etch CNTs while acetylene led to the additional growth of CNTs even faster in the second stage. As-grown CNTs were characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), and Raman spectroscopy.

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Meteorological Characteristics related to the Variation in Ozone Concentrations before, during, and after the Typhoon Period in the Korean Peninsula (한반도 태풍영향 전·중·후 시기동안 오존농도 변화에 관한 기상특성 분석)

  • Shin, Hyeonjin;Song, Sang-Keun
    • Journal of Environmental Science International
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    • v.26 no.5
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    • pp.621-638
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    • 2017
  • Meteorological characteristics related to variations in ozone ($O_3$) concentrations in the Korean peninsula before, during, and after Typhoon Talas (1112) were analyzed using both observation data and numerical modeling. This case study takes into account a high $O_3$ episode (e.g., a daily maximum of ${\geq}90ppb$) without rainfall. Before the typhoon period, high $O_3$ concentrations in the study areas (e.g., Daejeon, Daegu, and Busan) resulted from the combined effects of stable atmospheric conditions with high temperature under a migratory anticyclone (including subsiding air), and wind convergence due to a change in direction caused by the typhoon. The $O_3$ concentrations during the typhoon period decreased around the study area due to very weak photochemical activity under increased cloud cover and active vertical dispersion under a low pressure system. However, the maximum $O_3$ concentrations during this period were somewhat high (similar to those in the normal period extraneous to the typhoon), possibly because of the relatively slow photochemical loss of $O_3$ by a $H_2O+O(^1D)$ reaction resulting from the low air temperature and low relative humidity. The lowest $O_3$ concentrations during the typhoon period were relatively high compared to the period before and after the typhoon, mainly due to the transport effect resulting from the strong nocturnal winds caused by the typhoon. In addition, the $O_3$ increase observed at night in Daegu and Busan was primarily caused by local wind conditions (e.g., mountain winds) and atmospheric stagnation in the wind convergence zone around inland mountains and valleys.

Dietary Effects of Polymannuronate Added to Hamburger Buns on Lipid Metabolism in Rats (Polymannuronate 첨가에 의한 햄버거빵이 흰쥐의 지질대사에 미치는 영향)

  • Joh, Ihn-Seon;Kim, In-Hye;Kwon, Mi-Jin;Nam, Taek-Jeong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.2
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    • pp.187-192
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    • 2015
  • The dietary fiber alginic acid has no nutritional value; however, it decreases the utilization of nutrients by the body and can prevent obesity, hyperlipidemia, arteriosclerosis, constipation, and colon cancer. The low-molecular-weight alginic acid polymannuronate improves serum and liver lipid metabolism by decreasing cholesterol levels in high-cholesterol groups and may be used to control high blood pressure. Previously, we showed that polymannuronate, a physiologically active agent from seaweed, has a lipid-lowering effect and preventative role in colon cancer. In addition, the differentiation of polymannuronate-treated adipocytes was inhibited, triggering decreased leptin expression. This study examined ways to increase dietary satisfaction with and improve the nutritional quality of polymannuronate using hamburger buns supplemented with polymannuronate. Twenty male Sprague-Dawley rats were divided into two groups: the control group was fed hamburger buns containing 6% gluten, while the experimental group was fed hamburger buns containing 6% gluten and 10% polymannuronate. The serum triglyceride, phospholipid, and total and free cholesterol levels of the rats in the experimental group were decreased compared with those of the controls. The serum aspartate aminotransferase activity levels did not differ between the two groups. This study demonstrates that polymannuronate has beneficial effects on lipid metabolism and may be commercially useful.

Relationship Between Frictional Sounds and Mechanical Properties of Vapor Permeable Water Repellent Fabrics for Active Wear (스포츠웨어용 투습발수직물의 마찰음과 역학적 성질 간의 상관성)

  • Yang, Yoon-Jung;Park, Mi-Ran;Cho, Gil-Soo
    • Fashion & Textile Research Journal
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    • v.10 no.4
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    • pp.566-571
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    • 2008
  • Frictional sounds of 8 vapor permeable water repellent fabrics by sound generator were recorded and analyzed through FFT fast Fourier transform analysis. The frictional Sounds were quantified by calculating level pressure of total sound(LPT), the level range(${\Delta}L$) and the frequency difference(${\Delta}f$). Mechanical properties were measured by KES-FB. LPT values of specimens finished wet coating were higher than those of other kinds of finishing. ${\Delta}L$ values of specimens laminated were highest. Absolute values of ${\Delta}f$ were high in the cire finished and laminated specimens. Values for bending rigidity, shear stiffness and energy required for the compression of coated specimens increased compared with the cire finished and laminated specimens. Laminated specimens had high values of frictional coefficient and low values of surface roughness. Relationship between frictional sounds and mechanical properties analysed by use of correlation coefficients and stepwise regression. LPT showed significant correlation with elongation, tensile energy, geometrical roughness, weight and thickness. ${\Delta}L$ was highly correlated with tensile linearity, frictional coefficient, and ${\Delta}f$ with tensile linearity, weight and thickness. LPT were revealed to be explained by elongation and weight. ${\Delta}L$were predicted by tensile linearity, and ${\Delta}f$ by tensile linearity and thickness.

Degradation of Bradykinin, a Cardioprotective Substance, during a Single Passage through Isolated Rat-Heart

  • Ahmad M.;Zeitlin I.J.;Parratt J.R.;Pitt A.R.
    • Archives of Pharmacal Research
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    • v.29 no.3
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    • pp.241-248
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    • 2006
  • Angiotensin converting enzyme (ACE) inhibitors have cardioprotective effects in different species including human. This cardioprotective effect is mainly due to the inhibition of bradykinin (BK) degradation rather than inhibition of the conversion of angiotensin I to angiotensir. II. Bradykinin, a nonapeptide, has been considered to be the potential target for various enzymes including ACE, neutral endopeptidase 24.11, carboxypeptidase M, carboxypeptidase N, proline aminopeptidase, endopeptidase 24.15, and meprin. In the present study, the coronary vascular beds of Sprague Dawley rat isolated hearts were perfused (single passage) with Krebs solution alone or with different concentrations of BK i.e. $2.75{\times}10^{-10},\;10^{-7},\;10^{-6}\;and\;10^{-5}M$ solution. Percent degradation of BK was determined by radioimmunoassay. The degradation products of BK after passing through the isolated rat-hearts were determined using RP-HPLC and mass spectroscopy. All the four doses of BK significantly decreased the perfusion pressure during their passage through the hearts. The percentage degradation of all four doses was decreased as the concentration of drug was increased, implying saturation of a fixed number of active sites involved in BK degradation. Bradykinin during a single passage through the hearts degraded to give [1-7]-BK as the major metabolite, and [1-8]-BK as a minor metabolite, detected on HPLC. Mass spectroscopy not only confirmed the presence of these two metabolites but also detected traces of [1-5]-BK and arginine. These findings showed that primarily ACE is the major cardiac enzyme involved in the degradation of bradykinin during a single passage through the coronary vascular of bed the healthy rat heart, while carboxypeptidase M may have a minor role.

Effects of Shikonin Pigments from the Roots of Lithospermum eryhrorhizon on Rabbit Platelets (자근으로부터 혈소판에 작용하는 천연색소물질에 관한 연구)

  • 박영현;장성근
    • Journal of Food Hygiene and Safety
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    • v.15 no.2
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    • pp.167-172
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    • 2000
  • Lithospermum erythrorhyzon has been used as a red fooddye and traditional Chinese medicine to treat wounds, skin diseases and burns. Platelet activation plays an important role in thrombosis and haemostasis. Here, we studied the inhibition of platelet activation and its active compound from the root of Lithospermum erythrorhyzon. Its ethyl acetate extract inhibited the aggregation of washed rabbit platelets induced by collagen or thrombin. Five naphthoquinone pigments , shikonin , acetylshikonin , is obutylshikonin, $\alpha$-methyl-n-butylshikonin and $\beta$,$\beta$-dimethylacrylshikonin were isolated by means of high pressure liquid chromatography. The structures were determined by comparison of their proton nuclear magnetic resonance spectra. The potency of their inhibition was in the following order : $\beta$,$\beta$-dimethylacrylshikonin$\geq$$\alpha$-methyl-n-butylshikonin>isobutylshikonin>acetylshikonin>shikonin. It is suggested that the size of the aliphatic hydroxy group of shikonin is important for the enhancement of potency.

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Fabrication and Inertia Dynamic Friction Properties of Pitch-based Carbon-Carbon Composites

  • Lee, Jinyong;Suhr, Dong-Soo;Lim, Yun-Soo;Lee, Seung-Goo;Park, Jong-Kyoo
    • The Korean Journal of Ceramics
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    • v.4 no.3
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    • pp.193-198
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    • 1998
  • This paper presents the effects of an initial braking velocity, a braking pressure, and the number of braking stop on the tribological behaviors for the three different C-C composites using an inertia dynamic-friction tester. The C-C composites were prepared through the processes of several cycles of pitch impregnation/carbonization with different friction surface texture such as continuous 8-harness satin fabric (ADD-1), chopped fiber (ADD-2) and chopped fiber (ADD-3) having higher fiber volume fraction on friction than ADD-2 by about 10%. ADD-1 exhibited a higher fraction coefficient (0.41~0.33) than those of ADD-2 and ADD-3 (0.32~0.26) under the various initial braking velocities and braking pressures. The fraction coefficients decreased with increasing the initial velocity and the braking pressures. Wear rate by the thickness change after every 25 stop indicated that ADD-2 and ADD-3 having 1.7~2.7 $\mu\textrm{m}$/stop/pair were much lower than that of ADD-1 showing 5.0~6.5 $\mu\textrm{m}$/stop/pair. All specimens showed a little bit lower wear rate during the middle stage than the initial and latter stages among 100 braking stops. ADD-1 showed higher friction coefficient and wear rate due to the active pull-out of the fibers, evidenced by thicker were film and wear debrises.

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Equivalent Circuit Modelling of FFR Transducer Array for Sonar System Design (소나 시스템 설계를 위한 FFR 트랜스듀서 어레이의 등가회로 모델링)

  • Kim, In-Dong;Choi, Seung-Soo;Lee, Haksue;Lee, Seung Woo;Moon, Wonkyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.4
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    • pp.629-635
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    • 2017
  • Free-Flooded Ring (FFR) transducer array for use in Sonar system can be driven with large amplitude in a wide frequency band due to its structural characteristics, in which two resonances of a ring mode (1st radial mode) and an inner cavity vibration mode occur in a low frequency band. Since its sound wave generation characteristics are not influenced by the water pressure, the FFR transducer array is widely used in the deep sea. So FFR has been recognized as a low-frequency active sound source and has received much attention ever since. In order to utilize the FFR transducer array for SONAR systems in military and industrial applications, its equivalent electric circuit model is necessary especially to design the matching circuit between the driving power amplifier and the FFR transducer array. Thus this paper proposes the equivalent electric circuit model of FFR transducer array by using measured values of parameter, and suggest the improved method of parameter identification. Finally it verifies the effectiveness of the proposed circuit model of FFR transducer array by experimental measurements.