• 제목/요약/키워드: Slow waves

검색결과 109건 처리시간 0.027초

Theoretical observation of waves in cancellous bone

  • Yoon, Young-June;Chung, Jae-Pil
    • 한국정보전자통신기술학회논문지
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    • 제13권5호
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    • pp.419-424
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    • 2020
  • Poroelasticity theory has been widely used for detecting cancellous bone deterioration because of the safe use for humans. The tortuosity itself is an important indicator for ultrasound detection for bone diseases. The transport properties of cancellous bone are also important in bone mechanotransduction. In this paper, two important factors, the wave velocity and attenuation are examined for permeability (or tortuosity). The theoretical calculation for the relationship between the wave velocity (and attenuation) and permeability (or tortuosity) for cancellous bone is shown in this study. It is found that the wave along the solid phase (trabecular struts) is influenced not by tortuosity, but the wave along the fluid wave (bone fluid phase) is affected by tortuosity significantly. However, the attenuation is different that the attenuation of a fast wave has less influence than that of a slow wave because the slow wave is observed by the relative motion between the solid and fluid phases.

The Stomach's Communication with Its Related Acupoints, and the "Intelligent Tissue" Hypothesis

  • Kovich, Fletcher
    • Journal of Acupuncture Research
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    • 제36권1호
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    • pp.21-27
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    • 2019
  • Background: The intelligent tissue hypothesis holds that an organ's states (be it normal function or stressed states) are reflected in real time at its related acupuncture points (acupoints), causing physical, real-time changes in the local tissue. The experiment was devised to test this. Methods: The patient drank chilled water while the impedance at 6 stomach-related acupoints was monitored in real time (sample rate of 1 kHz). Any changes in the local tissue at the acupoints ought to be reflected in changes in the impedance. Results: The impedance at every test acupoint showed a response to the chilled water being ingested. Also, the duodenal pacesetter and the stomach's slow waves were clearly visible in the impedance pattern at all the acupoints. Conclusion: Hence, many separate details of the stomach's function were reflected at these acupoints. The duodenal features were consistent with the traditional indications for these acupoints, which are noted to be able to treat intestinal conditions. Therefore, the results were consistent with the hypothesis and also provided a possible explanation for how the use of these acupoints is able to treat intestinal conditions.

다점 계류된 원유 저장선에 대한 저주파수 운동 해석 (Slow Drift Motion Analyses for a FPSO with Spread Mooring Systems)

  • 이호영;박종환;곽영기
    • 한국해안해양공학회지
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    • 제13권3호
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    • pp.195-201
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    • 2001
  • 본 논문은 파랑중에 다전 계류된 원유저장선에 대한 저주파수 운동을 수치 모사하였다. 시간영역에서의 운동방정식은 충격응답함수를 포함하여 수평면상의 운동 즉 전후, 좌우 및 선수 운동을 고려하였다. 시간영역의 운동방정식에 나타난 부가질량, 파랑감쇠계수, 1차항 파랑 강제력 그리고 2차항 파랑 강제력을 주파수 영역의 특이점 분포법을 사용하여 계산하였고, 다점 계류된 계류삭은 체인이 해저면에 닿은 운동 효과를 포함하여 준 정적 현수선 이론으로 산정되었다. 계산 예로서 장파정 불규칙 파랑 중에 놓인 바아지식 원유저장선에 대한 시간 영역 해석을 수행하였다.

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기니피그 위 평활근의 기계적 및 전기적 활동에 대한 아데노신 효과 (Effect of Adenosine on the Mechanical and Electrical Activities of Guinea-pig Stomach)

  • 김희진;고광욱;서인석;김기환
    • The Korean Journal of Physiology
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    • 제21권2호
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    • pp.225-239
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    • 1987
  • The effects of adenosine on the mechanical contractions and electrical activities were investigated in guinea-pig stomach. Spontaneous contractions of the antral region were recorded with force transducer, and the phasic contractions of fundic region were induced by electrical field stimulation. Electrical responses of smocth muscle cells were recored using glass capillary microelectrodes filled with 3M-KCl. Field stimulation was applied transmurally by using a pair of platinum wire (0.5 mm in diameter) placed on both sides of tissue. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% $O_2$ and kept at $35^{\circ}C$. The results obtained were as follows. 1) Adenosine suppressed the spontaneous contractions of antrum in a dose-dependent manner. 2) The inhibitory effect on antral spontaneous contractions was not influenced by the administration of guanethidine $(5{\times}10^{-6}\;M)$ and atropine $10^{-6}\;M$, or in the presence of dipyridamole $10^{-7}\;M$. 3) The phasic contractions of fundus induced by electrical field stimulation, which disappeared rapidly by the addition of tetrodotoxin $(3{\times}10^{-7}\;M)$, were potentiated by adenosine in the presence of guanethidine. 4) Adenosine decreased the amplitude and the maximum rate of rise of slow waves, and the increased amplitude and rate of rise evoked in the high calcium solution or in the presence of TEA were decreased by adenosine. 5) The non-adrenergic, non-cholinergic inhibitory junction potential (IJP) was inhibited by adenosine in the antral region, while the excitatory junction potential (EJP) in the fundic region was potentiated. From the above results, the following conclusions could be made. 1) Adenosine suppresses the spontaneous contractions of antrum strip by the decrease in amplitude and rate of rise of slow waves. 2) The release of neurotransmitter(s) from non-adrenergic, non-cholinergic nerve terminals is inhibited by adenosine.

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Effects of Cranial Electrotherapy Stimulation on Electrocephalogram

  • Lee, Jeongwoo;Lee, Hyejein;Park, Woongsik
    • 국제물리치료학회지
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    • 제10권1호
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    • pp.1687-1694
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    • 2019
  • Background: Although cranial electrotherapy stimulation (CES) is reported to have positive effects on mental functions such as depression and sleep improvement, detailed studies regarding awakening, attention and concentration among brain waves reflecting brain activity are lacking. Objective: To examine the effects of cranial electrotherapy stimulation (CES) on various electroencephalograms (EEGs) reflecting brain activities. Design: Randomized controlled clinical trial (single blind) Methods: This study selected 30 healthy adult women in their 20s who volunteered for this experiment. A total of 30 subjects were randomly assigned to three groups (Sham group, 0.5 Hz CES group, and 100 Hz CES group). EEGs were measured before and after the single CES, and the results were compared and analyzed. Results: The relative theta, alpha, and gamma waves indicated no significant differences in the interaction effects between time and group. The relative fast alpha wave only showed significant differences in the interaction effects between time and group in P4. The relative slow beta wave only indicated statistically significant differences in the interaction effects between time and group in T3 and T4. The relative mid and fast beta waves showed statistically significant differences in the interaction effects between time and group in all areas. Conclusions: These results suggest that a CES of 0.5 Hz awakens consciousness and has a positive influence on brain activity, while a CES of 100 Hz has a positive influence on thinking activity accompanying mental load during concentrating on one subject.

뇌파를 이용한 두개천골요법 기반 베개의 수면유도 효과 검증 (Evaluation of Cranial Sacral Therapy (CST) Based Pillow on Sleep Induction Using the Electroencephalogram (EEG))

  • 권혁찬;표정빈;박용길;이현주;태기식
    • 대한의용생체공학회:의공학회지
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    • 제39권1호
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    • pp.55-61
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    • 2018
  • The purpose of this study was to investigate the effect of a pillow simulated with cranial sacral therapy (CST) on sleep induction using electroencephalography (EEG). This study included 12 voluntary participants divided into experimental group (CST group) and control group (Non-CST group) to observe EEG changes. The position of the electrode for EEG measurement consists of 8 channels electrodes (Fp1, Fp2, F3, F4, T3, T4, P3 and P4). In this study, we measured the fall asleep time, change of brain activity and sleep wave ratio using EEG wave (${\delta}$, ${\theta}$, ${\alpha}$, ${\beta}$ and ${\gamma}$). As a result, the mean fall asleep time of the experimental group was shorter than that of the control group significantly (p < 0.001). Also in comparison with the control group, both the delta (d) and theta (q) wave corresponding to the slow waves showed a larger increase and the alpha (a) wave showed a larger decrease significantly. The slow waves of experimental group showed a higher rate of significant increase than the control group (p < 0.001). Therefore this study showed that pillow based on CST had an effective in improving sleep induction and quality.

기능성 소화불량증 환자의 변증증후(辨證證候)에 의한 건강상태와 위 운동성의 상관성에 대한 연구 (기혈수(氣血水) 변증(辨證)과 위전도 지표를 중심으로) (Relationship between Gastric Motility and Health Condition Graded by Total Symptom Scores in Comprehensive Diagnosis of Qui Xue Shui in Functional Dyspeptic Patients)

  • 정하덕;김진성;류봉하;류기원;윤상협
    • 대한한방내과학회지
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    • 제25권4호
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    • pp.158-166
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    • 2004
  • Background & Object : The aim of this study was to investigate the usefulness of electrogastrography in the diagnosis field of traditional medicine through a study of the relationship between gastric motility and health condition based on oriental medicine diagnostic theory in functional dyspepsia. Method : 86 patients (male 27, female 59) with functional dyspepsia and 10 healthy control subjects (male 5, female 5) were involved in the investigation. The disease information of functional dyspepsia (based on Rome criteria II) was used for dyspeptic index and scores were obtained from the comprehensive diagnosis of Qui, Xue, Shui was applied as index for health condition, those were all investigated by questionnaire. Gastric motility were recorded and analyzed using electrogastrography in fasting and postprandial period. Results : The total score of comprehensive diagnosis of Qui Xue Shui was influenced by the number of functional dyspepsia symptoms (p=0.026). In terms of electrogastrographical parameters, both postpranial normal slow waves regularity(p=0.003) and power ratio (p=0.001) in the patients had the statistical significance and they showed an incremental inverse correlation with the number of symptoms. Dominant frequency and fasting normal slow waves regularity ratio had no statistical significance. Conclusion : Results suggest that electrogastrography is useful in evaluating the health condition of patient by comprehensive diagnosis of Qui Xue Sui.

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홍화가 위장관 카할간질세포에 미치는 효과 (Effects of Carthami Flos on Interstitial Cells of Cajal in the Gastrointestinal Tract)

  • 송호준;김정아;한송이;김형우;채한;김병주;권영규
    • 동의생리병리학회지
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    • 제25권4호
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    • pp.603-607
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    • 2011
  • The purpose of this study is to investigate the effects of Carthami Flos on interstitial cells of Cajal in the gastrointestinal tract. Many regions of the tunica muscularis of the gastrointestinal (GI) tract display spontaneous contraction. These spontaneous contractions are mediated by periodic generation of electrical slow waves. Recent studies have shown that the interstitial cells of Cajal (ICCs) act as pacemakers and conductors of electrical slow waves in gastrointestinal smooth muscles. We investigated the cytotoxicity activity, antioxidant activity, and pacemaking activity. The cytotoxicity activity was measured by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Antioxidant activities were determined by DPPH (1.1-diphenyl-2-picrylhydrazyl) radical scavenging capacity assay and DCFH-DA (2,7-dichlorofluorescein diacetate) method. The effects of Carthami Flos on the pacemaker potentials in cultured ICCs from murine small intestine were investigated by using whole-cell patch-clamp techniques at $30^{\circ}C$. The addition of Carthami Flos (5, 10, $30{\mu}g$/ml) depolarized the resting membrane potentials in a concentration dependent manner. These results suggest that the GI tract can be targets for Carthami Flos, and their interaction can affect intestinal motility.

TRPC4 Is an Essential Component of the Nonselective Cation Channel Activated by Muscarinic Stimulation in Mouse Visceral Smooth Muscle Cells

  • Lee, Kyu Pil;Jun, Jae Yeoul;Chang, In-Youb;Suh, Suk-Hyo;So, Insuk;Kim, Ki Whan
    • Molecules and Cells
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    • 제20권3호
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    • pp.435-441
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    • 2005
  • Classical transient receptor potential channels (TRPCs) are thought to be candidates for the nonselective cation channels (NSCCs) involved in pacemaker activity and its neuromodulation in murine stomach smooth muscle. We aimed to determine the role of TRPC4 in the formation of NSCCs and in the generation of slow waves. At a holding potential of -60 mV, $50{\mu}M$ carbachol (CCh) induced $I_{NSCC}$ of amplitude [$500.8{\pm}161.8pA$ (n = 8)] at -60 mV in mouse gastric smooth muscle cells. We investigated the effects of commercially available antibodies to TRPC4 on recombinant TRPC4 expressed in HEK cells and CCh-induced NSCCs in gastric smooth muscle cells. TRPC4 currents in HEK cells were reduced from $1525.6{\pm}414.4pA$ (n = 8) to $146.4{\pm}83.3pA$ (n = 10) by anti-TRPC4 antibody and $I_{NSCC}$ amplitudes were reduced from $230.9{\pm}36.3pA$ (n = 15) to $49.8{\pm}11.8pA$ (n = 9). Furthermore, $I_{NSCC}$ in the gastric smooth muscle cells of TRPC4 knockout mice was only $34.4{\pm}10.4pA$ (n = 8) at -60 mV. However, slow waves were still present in the knockout mice. Our data suggest that TRPC4 is an essential component of the NSCC activated by muscarinic stimulation in the murine stomach.

Ultrasonic Phase Velocity and Attenuation Coefficient Predicted by Biot's Theory and the MBA Model in Cancellous Bone

  • Lee Kang Il;Yoon Suk Wang
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 2004년도 추계학술발표대회논문집 제23권 2호
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    • pp.183-186
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    • 2004
  • Biot's theory and a modified Biot-Attenborough (MBA) model are applied to predict the dependences of acoustic characteristics on frequency and porosity in cancellous bone. The phase velocity and the attenuation coefficient predicted by both theories are compared with previous in vitro experimental measurements in terms of the mixed, the fast, and the slow waves. Biot's theory successfully predicts the dependences of phase velocity on frequency and porosity in cancellous bone, whereas a significant discrepancy is observed between predicted and measured attenuation coefficients. The MBA model is consistent with reported measurements for both dependences of phase velocity and attenuation coefficient on frequency and porosity. Based on the theoretical predictions from the MBA model, it is suggested that the attenuation coefficient of the mixed wave is dominated by the fast wave in the low-porosity region while it is dominated by the slow wave in the high-porosity region. This provides a qualitative explanation for the nonlinear relationship of attenuation of the mixed wave with porosity in cancellous bone.

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