ELECTRET CONDENSER MICROPHONE AS SENSOR IN ARTERIAL PULSE RECORDING DEVICE

2020 ◽  
Vol 19 (72) ◽  
Author(s):  
Erni Yudaningtyas
Keyword(s):  
Recording Device ◽  
Arterial Pulse ◽  
Condenser Microphone

scholarly journals Electret condenser microphone as a traditional Chinese medicine arterial pulse sensor

2018 ◽  
Vol 197 ◽  
pp. 11024
Author(s):  
Erni Yudaningtyas ◽  
Waru Djuriatno ◽  
Achsanul Khabib ◽  
Dionysius J.D.H. Santjojo
Keyword(s):  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Pulse Signal ◽  
Arterial Pulse ◽  
Mechanical Coupling ◽  
Condenser Microphone ◽  
Average Accuracy ◽  
Pulse Sensor ◽  
Source Signal ◽  
The Subject

Arterial pulse signal reading by a therapist in Traditional Chinese Medicine (TCM) requires considerable experience and thoroughness. The interpretation resulted by the therapist is very subjective. The objectivity of the device can be achieved by increasing the accuracy and the consistency of the reading in the range of 1-2 Hz. An electret condenser microphone (ECM) can be used as a pulse sensor in such device. This study reveals that ECM performs a number of advantages such as small-sized and inexpensive. Unfortunately, this ECM also picks up mechanical noises during direct contact with the subject. This study proposed soft silicon rubber as a medium between subjects and ECM. The technique was designed to enhance the mechanical coupling between the ECM and the source signal without affecting the signal source. The results show that the ECM could measure the signal of 0.5-10 Hz with the average accuracy of 99,47%.

Evaluation of single-electron movies of glutamine synthetase molecules

1983 ◽  
Vol 41 ◽  
pp. 280-281
Author(s):  
W. Kunath ◽  
E. Zeitler ◽  
M. Kessel
Keyword(s):  
Electron Microscope ◽  
Glutamine Synthetase ◽  
Electron Irradiation ◽  
Structural Damage ◽  
Structural Changes ◽  
Single Electron ◽  
Continuous Series ◽  
Digital Recording ◽  
Recording Device ◽  
Low Exposure

The features of digital recording of a continuous series (movie) of singleelectron TV frames are reported. The technique is used to investigate structural changes in negatively stained glutamine synthetase molecules (GS) during electron irradiation and, as an ultimate goal, to look for the molecules' “undamaged” structure, say, after a 1 e/Å2 dose.The TV frame of fig. la shows an image of 5 glutamine synthetase molecules exposed to 1/150 e/Å2. Every single electron is recorded as a unit signal in a 256 ×256 field. The extremely low exposure of a single TV frame as dictated by the single-electron recording device including the electron microscope requires accumulation of 150 TV frames into one frame (fig. lb) thus achieving a reasonable compromise between the conflicting aspects of exposure time per frame of 3 sec. vs. object drift of less than 1 Å, and exposure per frame of 1 e/Å2 vs. rate of structural damage.

A Rapid Radioisotope Dilution Technique for the Accurate Determination of the Cardiac Output

1968 ◽  
Vol 07 (01) ◽  
pp. 1-7
Author(s):  
Muhammad Razzak ◽  
Robert Botti ◽  
William MacIntyre
Keyword(s):  
Cardiac Output ◽  
Isotope Dilution ◽  
Accurate Determination ◽  
Differential Count ◽  
Stroke Index ◽  
Recording Device ◽  
Dilution Curve ◽  
Index Stroke Volume ◽  
Index Stroke ◽  
Comparison Of The Results

SummaryA pair of printing scalers was used to record the information obtained by external monitoring of the isotope dilution curve following the intravenous injection of radioiodinated human serum albumin. The first scaler gives the differential count rate of the curve at increments of one second, whereas the second integrates continuously the isotope dilution curve. This recording device enabled cardiac output determinations to be calculated rapidly at the bedside without any loss in accuracy.Using this method in 15 normal individuals, the cardiac output was found to be 6.13 ± 0.73 liters/minute (Mean ± 1 S.D.), with a cardiac index of 3.36 ± 0.35 liters/minute/m2. In the same group of normals, the stroke index (stroke volume/surface area) amounted to 50 ± 7.3 ml/beat/m2.Comparison of the results of this method with those obtained by integration of the entire isotope dilution curve by an IBM 1620 computer showed excellent agreement, proving the validity of the suggested technique.

Cardiac-Related Sympathetic Nerve Activity during Circulation with Only the Left Ventricular Assist Device

1992 ◽  
Vol 15 (1) ◽  
pp. 49-54 ◽  
Author(s):  
T. Yambe ◽  
S. Nitta ◽  
Y. Katahira ◽  
T. Sonobe ◽  
S. Naganuma ◽  
...  
Keyword(s):  
Sympathetic Nerve ◽  
Sympathetic Nerve Activity ◽  
Pulse Wave ◽  
Left Ventricular ◽  
Arterial Pulse ◽  
Assist Device ◽  
Ventricular Assist ◽  
Arterial Pulse Wave ◽  
Left Ventricular Assist ◽  
Renal Sympathetic

Circulatory maintenance with a left ventricular assist device (LVAD) alone during cardiac arrest until heart transplantation has been evaluated. To assess the effect on the autonomic nervous system, the sympathetic neurogram was analyzed by power spectrum and coherence function. LVAD were inserted between the left atrium and the descending aorta in seven adult mongrel dogs and ventricular fibrillation was induced electrically. Renal sympathetic nerve activity (RSNA) was detected by bipolar electrodes attached to the left renal sympathetic nerve. Values of squared coherence between the arterial pulse wave and RSNA were calculated. Under the condition of circulatory maintenance with only LVAD, coherence at the cardiac rhythm frequency was decreased, and coherence at the LVAD pumping rhythm frequency was increased. These results indicate that the arterial pulse wave observed during maintenance of the circulation with only LVAD contributed to the sympathetic neurogram.

scholarly journals Usefulness of Surgical Media Center as a Cataract Surgery Educational Tool

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Tomoichiro Ogawa ◽  
Takuya Shiba ◽  
Hiroshi Tsuneoka
Keyword(s):  
Cataract Surgery ◽  
Surgical Procedures ◽  
Intraoperative Complications ◽  
Recording Device ◽  
Educational Tool ◽  
Intraoperative Complication ◽  
Vacuum Level ◽  
Media Center ◽  
Medical Optics ◽  
Education Tool

Purpose.This study retrospectively analyzed cataract surgeries to examine the usefulness of Surgical Media Center (SMC) (Abbott Medical Optics Inc.), a new cataract surgery recording device, for training of cataract surgery.Methods.We studied five hundred cataract surgeries conducted with a phacoemulsification system connected to the SMC. After surgery, the surgical procedures were reviewed, with changes in aspiration rate, vacuum level, and phaco power displayed as graphs superimposed on the surgical video. We examined whether use of SMC is able to demonstrate the differences in technique between experienced and trainee operators, to identify inappropriate phacoemulsification techniques from analyzing the graphs, and to elucidate the cause of intraoperative complications.Results. Significant differences in the time taken to reach maximum vacuum and the speed of increase in vacuum during irrigation and aspiration were observed between experienced and trainee operators. Analysis of the graphs displayed by SMC detected inappropriate phacoemulsification techniques mostly in cases operated by trainee operators.Conclusions. Using SMC, it was possible to capture details of cataract surgery objectively. This recording device allows surgeons to review cataract surgery techniques and identify the cause of intraoperative complication and is a useful education tool for cataract surgery.

A Wireless Fully Passive Neural Recording Device for Unobtrusive Neuropotential Monitoring

2016 ◽  
Vol 63 (1) ◽  
pp. 131-137 ◽  
Author(s):  
Asimina Kiourti ◽  
Cedric W. L. Lee ◽  
Junseok Chae ◽  
John L. Volakis
Keyword(s):  
Neural Recording ◽  
Recording Device

Half inch condenser microphone

1961 ◽  
Vol 38 (4) ◽  
pp. 168-168
Author(s):  
Bruel & Kjaer Laboratories Ltd.
Keyword(s):  
Condenser Microphone

scholarly journals Novel Application of a Multiscale Entropy Index as a Sensitive Tool for Detecting Subtle Vascular Abnormalities in the Aged and Diabetic

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Hsien-Tsai Wu ◽  
Men-Tzung Lo ◽  
Guan-Hong Chen ◽  
Cheuk-Kwan Sun ◽  
Jian-Jung Chen
Keyword(s):  
Glycosylated Hemoglobin ◽  
Reactive Hyperemia ◽  
Multiscale Entropy ◽  
Arterial Pulse ◽  
Vascular Changes ◽  
Entropy Index ◽  
Pressure Sensing ◽  
Vascular Abnormalities ◽  
Sensing System ◽  
Sensitive Tool

Although previous studies have shown the successful use of pressure-induced reactive hyperemia as a tool for the assessment of endothelial function, its sensitivity remains questionable. This study aims to investigate the feasibility and sensitivity of a novel multiscale entropy index (MEI) in detecting subtle vascular abnormalities in healthy and diabetic subjects. Basic anthropometric and hemodynamic parameters, serum lipid profiles, and glycosylated hemoglobin levels were recorded. Arterial pulse wave signals were acquired from the wrist with an air pressure sensing system (APSS), followed by MEI and dilatation index (DI) analyses. MEI succeeded in detecting significant differences among the four groups of subjects: healthy young individuals, healthy middle-aged or elderly individuals, well-controlled diabetic individuals, and poorly controlled diabetic individuals. A reduction in multiscale entropy reflected age- and diabetes-related vascular changes and may serve as a more sensitive indicator of subtle vascular abnormalities compared with DI in the setting of diabetes.

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