scholarly journals Infrared Sensor Detection and Actuator Treatment Applied during Hemodialysis

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2521
Author(s):  
Jian-Chiun Liou ◽  
Yu-Cheng Hsiao ◽  
Cheng-Fu Yang
Keyword(s):  
Blood Vessels ◽  
High Frequency ◽  
Near Infrared ◽  
Low Frequency ◽  
Far Infrared ◽  
Autonomic Nerve ◽  
Infrared Sensor ◽  
Nerve Activity ◽  
Infrared Rays ◽  
Sensor Detection

Infrared thermography can be applied in different medical systems, for example it can be used to catch the images of living blood vessels. Far infrared rays can be used in a heating machine, which can be applied in the clinical hemodialysis patients. Infrared electronically sensitized images, which are generated by near-infrared Charge-coupled Device (CCD), are used to detect blood vessels, and used as a long-wavelength external stimulating therapeutic tissue repair system. When an infrared sensor detection and actuator treatment is applied during hemodialysis, a missing needle can be detected, and far infrared rays have a therapeutic effect on blood vessels. Because a far-infrared actuated light source can improve blood circulation, it is currently used to prevent fistula embolism in hemodialysis (HD) patients and reduce vascular occlusion after hemodialysis. Sensors used for sudden changes in heart rate variability (HRV) are used as predictive and evaluation indicators for our new method. Far-infrared actuated radiation can increase sympathetic nerve activity and regulation of parasympathetic and sympathetic nerves. We performed baseline measurements of the low-frequency/high-frequency ratio of autonomic nerve activity before hemodialysis (low frequency (LF), high frequency (HF), LF/HF, before HD) and after hemodialysis (LF/HF, after-HD). Based on data from the HRV continuity tracking report, 35 patients with autonomic nerve activation were treated and evaluated. We have demonstrated that the resulting near-infrared (NIR) sensor imaging and far-infrared actuator illumination can be used for the detection and treatment of hemodialysis patients.

scholarly journals Low Frequency Cutoffs in the Spectra of Radioquiet Quasars

1987 ◽  
Vol 121 ◽  
pp. 135-139
Author(s):  
R. Antonucci ◽  
R. Barvainis
Keyword(s):  
High Frequency ◽  
Near Infrared ◽  
Dust Emission ◽  
Low Frequency ◽  
Far Infrared ◽  
Low Energy Electrons ◽  
Order Of Magnitude ◽  
Infrared Continuum ◽  
Lower Cutoff ◽  
Rule Out

Radio-quiet and normal radio-loud quasars have very similar spectral properties in the ultraviolet, optical and near infrared regions, but their radio powers differ by several orders of magnitude. Somewhere between the near infrared and the radio their spectra must diverge dramatically.The IRAS survey detected 17 radio quiet quasars and luminous Seyfert 1's with −29. 5 ≤ Mv ≤ −21.6 (for Ho = 75). By coadding the survey data and using pointed observations, we have detections of most of these objects in all four IRAS passbands. The spectra are all rising with wavelength all the way to 100μ. We are measuring fluxes in the centimeter, millimeter, and, together with R Cutri, the near infrared and optical regions for each of these objects. Our goal is to constrain the location, shape, and spectral context of the low frequency cutoffs. Here we present the IRAS, millimeter and centimeter data. Measurements at the other wavelengths are still in progress.Although the spectra are rising steeply between 60μ and 100μ, we find that all of our objects are undetectable at 1.3 mm with the NRAO 12-m telescope. Our limits are typically an order of magnitude below the 100μ fluxes. (Ennis et al (1982) and Robson et al (1985) have already shown that the 1 mm fluxes of some radio quiet quasars must be below the extrapolation of the near infrared continuum.) Our objects are all extremely weak or undetected with the VLA at 2 cm and 1.3 cm, at levels typically three orders of magnitude below the 100μ fluxes. The sharpness of the required cutoffs allows us to rule out the hypothesis that the infrared is synchrotron radiation with the cutoff due to an absence of low energy electrons. The high frequency of the cutoffs makes free-free absorption implausible, but not impossible. It is possible that synchrotron self-absorption is suppressing the radio. There is circumstantial evidence that the far infrared is thermal dust emission. This would require a lower cutoff in the distribution of dust temperatures, which we think we can explain.

The coordinate roles of branchial nerve activity and potassium in the stimulation of ciliary activity in Mytilus edulis: observations with phenoxybenzamine, bromolysergic acid and fluorescence histochemistry

1976 ◽  
Vol 65 (1) ◽  
pp. 109-116
Author(s):  
A. A. Paparo
Keyword(s):  
Mytilus Edulis ◽  
Nerve Stimulation ◽  
High Frequency ◽  
Low Frequency ◽  
Ciliary Activity ◽  
Nerve Activity ◽  
Basal Rate ◽  
Potassium Effect ◽  
Branchial Nerve ◽  
Stimulation Of

Potassium concentrations in excess of 30 mM increase the rate of beating of lateral cilia on the gill of Mytilus edulis. Cilioexcitation produced by low frequency (5 beats/s) electrical stimulation was potentiated with potassium but blocked with bromolysergic acid (a serotonergic inhibitor). Cilioinhibition produced by high frequency (50 beats/s) stimulation was decreased with potassium and phenoxybenzamine (a dopaminergic inhibitor). Phenoxybenzamine enhanced the cilioexcitation produced by potassium. Potassium doses incapable of maintaining a basal rate of beating (less than 30 mM) could increase ciliary activity if phenoxybenzamine was also added. After transection of the branchial nerve, the yellow-fluorophore (serotonergic storage) and cilioexcitatory effect of potassium gradually decrease. This study shows that the potassium effect on ciliary activity (a) increase with low frequency nerve stimulation, presumably through the release of serotonin and (b) decreases with high frequency nerve stimulation, presumably through the release of dopamine.

scholarly journals Heart Rate Variability and Hemodynamic Change in the Superior Mesenteric Artery by Acupuncture Stimulation of Lower Limb Points: A Randomized Crossover Trial

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Soichiro Kaneko ◽  
Masashi Watanabe ◽  
Shin Takayama ◽  
Takehiro Numata ◽  
Takashi Seki ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Superior Mesenteric Artery ◽  
Lower Limb ◽  
Mesenteric Artery ◽  
Low Frequency ◽  
Autonomic Nerve ◽  
Nerve Activity ◽  
Acupuncture Stimulation ◽  
Stimulation Of

Objective. We investigated the relationship between superior mesenteric artery blood flow volume (SMA BFV) and autonomic nerve activity in acupuncture stimulation of lower limb points through heart rate variability (HRV) evaluations.Methods. Twenty-six healthy volunteers underwent crossover applications of bilateral manual acupuncture stimulation at ST36 or LR3 or no stimulation. Heart rate, blood pressure, cardiac index, systemic vascular resistance index, SMA BFV, and HRV at rest and 30 min after the intervention were analyzed.Results. SMA BFV showed a significant increase after ST36 stimulation (0% to 14.1% ± 23.4%,P=0.007); very low frequency (VLF), high frequency (HF), low frequency (LF), and LF/HF were significantly greater than those at rest (0% to 479.4% ± 1185.6%,P=0.045; 0% to 78.9% ± 197.6%,P=0.048; 0% to 123.9% ± 217.1%,P=0.006; 0% to 71.5% ± 171.1%,P=0.039). Changes in HF and LF also differed significantly from those resulting from LR3 stimulation (HF: 78.9% ± 197.6% versus −18.2% ± 35.8%,P=0.015; LF: 123.9% ± 217.1% versus 10.6% ± 70.6%,P=0.013).Conclusion. Increased vagus nerve activity after ST36 stimulation resulted in increased SMA BFV. This partly explains the mechanism of acupuncture-induced BFV changes.

Effect of Auricular Acupuncture on Gastrointestinal Motility and Its Relationship with Vagal Activity

2013 ◽  
Vol 31 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Han Li ◽  
Yin-Ping Wang
Keyword(s):  
Vagus Nerve ◽  
High Frequency ◽  
Low Frequency ◽  
Autonomic Nerve ◽  
Auricular Acupuncture ◽  
Vagal Activity ◽  
Nerve Function ◽  
Gi Transit ◽  
The Relationship ◽  
Gi Motility

Background Vagus nerve stimulation is capable of regulating autonomic nerve function. In Traditional Chinese Medicine, the effect of auricular acupuncture (AA) is mediated by the vagus. This study was designed to investigate the effect of AA on gastrointestinal (GI) motility and the relationship of this effect with the vagus nerve. Methods 50 rats were divided into five groups for observation of the effects of different types of acupuncture and influencing factors: control, AA, somatic acupuncture (SA), atropine and atropine+AA. The acupuncture points used for AA were ST (Stomach) and SI (Small intestine), while the acupuncture point used for SA was ST36. Electroacupuncture was performed for 15 min. A model of reduced GI motility was established using ethanol, and GI transit rate was used to measure GI motility. Heart rate variability (HRV) and the effect of atropine administration were investigated to study the relationship between AA and vagal activity. Results The GI transit rate increased in both the AA and SA groups compared with control, and no significant difference was found between their effects. In addition, after atropine administration, AA was found to be ineffective in influencing the GI transit rate. In the HRV analysis, no significant differences were found in the absolute low frequency normalised units, high frequency normalised units or the low frequency/high frequency component ratio in the AA or SA groups compared with control. After administration of atropine AA still had no effect on HRV. Conclusions The function of AA in improving GI motility is similar to that of SA, and this effect can be blocked by the presence of atropine, indicating that this effect is regulated by the vagus. However, HRV did not reflect the acupuncture-induced changes in vagal nerve function.

scholarly journals Study on the Relationship Between Orthostatic Hypotension and Heart Rate Variability, Pulse Wave Velocity Index, and Frailty Index in the Elderly: A Retrospective Observational Study

2020 ◽  
Vol 7 ◽  
Author(s):  
Lun Li ◽  
Huanhuan Li ◽  
Li He ◽  
Hongyan Chen ◽  
Yunqiao Li
Keyword(s):  
Heart Rate ◽  
High Frequency ◽  
Cardiac Cycle ◽  
Pulse Wave ◽  
Frailty Index ◽  
Low Frequency ◽  
The Elderly ◽  
Autonomic Nerve ◽  
Autonomic Nerve Function ◽  
The Relationship

Background: Orthostatic hypotension (OH) is a common disease of the elderly. It is generally believed that the pathogenesis of OH is related to the impairment of autonomic nerve function and the decreased vascular capacity regulation. This study aims to explore the relationship between OH and heart rate variability (HRV) parameters, which reflects autonomic nerve function; ankle-brachial pressure index (ABI), which reflects the degree of vascular stenosis; pulse wave velocity (PWV) index, which reflects vascular stiffness; and frailty index (FI), which reflects the overall health status of the elderly.Methods: From January to September 2018, 24-h HOLTER monitoring, PWV, and ABI were performed in 108 elderly patients with OH and 64 elderly patients who underwent physical examination in our hospital. Analysis software was used to record the subject's standard deviation of the cardiac cycle (SDNN), the standard deviation of the 5-min average cardiac cycle (SDANN), the square root of the average square sum of consecutive n-interval differences (rMSSD), the percentage of the number of adjacent cardiac interval differences >50 ms (pNN50), low frequency (LF), high frequency (HF), very low frequency (VLF), and low frequency/high frequency ratio (LF/HF). Then, FI was evaluated qualitatively and quantitatively in the form of a scale.Results: There was no statistical difference between the two groups on the basis of age, sex, body mass index (BMI), low-density lipoprotein (LDL), resting heart rate, blood pressure, fasting blood glucose, long-term medication, etc. There were significant differences in PWV, SDNN, LF, VLF, and LF/HF between the two groups (P < 0.05). The risk factor of OH in the qualitative (P = 0.04) and quantitative (P = 0.007) index FI was higher in the OH group than in the control group. The risk factors of OH were PWV, SDNN, VLF, LF/HF, and FI, where FI was positively correlated and LF/HF was negatively correlated.Conclusions: The pathogenesis of OH is related to vascular stiffness, imbalance of autonomic nerve regulation, and its comprehensive health status in the elderly. However, arteriosclerosis has not been confirmed as an independent risk factor.Clinical Trial Registration: Retrospectively registered, http://www.chictr.org.cn.

scholarly journals Higher pulse frequency of near-infrared laser irradiation increases penetration depth for novel biomedical applications

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245350
Author(s):  
Ayan Barbora ◽  
Oryan Bohar ◽  
Ariel Alexander Sivan ◽  
Eyal Magory ◽  
Ariel Nause ◽  
...  
Keyword(s):  
Visible Light ◽  
High Frequency ◽  
Near Infrared ◽  
Continuous Wave ◽  
Low Frequency ◽  
Pulse Frequency ◽  
Nir Light ◽  
Cw Laser ◽  
Chicken Tissue ◽  
Penetration Depths

Background The clinical efficiency of laser treatments is limited by the low penetration of visible light used in certain procedures like photodynamic therapy (PDT). Second Harmonic Generation (SHG) PDT is an innovative technique to overcome this limitation that enables the use of Near Infrared (NIR) light instead of visible light. NIR frequency bands present an optical window for deeper penetration into biological tissue. In this research, we compare the penetration depths of 405 and 808 nm continuous wave (CW) lasers and 808 nm pulsed wave (PW) laser in two different modes (high and low frequency). Methods Increasing thicknesses of beef and chicken tissue samples were irradiated under CW and PW lasers to determine penetration depths. Results The 808 nm CW laser penetrates 2.3 and 2.4 times deeper than the 405 nm CW laser in beef and chicken samples, respectively. 808 nm PW (pulse frequency—500 Hz) penetrates deeper than CW laser at the same wavelength. Further, increasing the pulse frequency achieves higher penetration depths. High frequency 808 nm PW (pulse frequency—71.4 MHz) penetrates 7.4- and 6.0-times deeper than 405 nm CW laser in chicken and beef, respectively. Conclusions The results demonstrate the higher penetration depths of high frequency PW laser compared to low frequency PW laser, CW laser of the same wavelength and CW laser with half the wavelength. The results indicate that integrating SHG in the PDT process along with pulsed NIR light may allow the treatment of 6–7 times bigger tumours than conventional PDT using blue light.

Abstract 16157: Catheter Ablation Induces an Increase in Heart Rate With Discordant With a Decrease in Sympathetic Nerve Activity in Patients With Paroxysmal Atrial Fibrillation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Yusuke Mukai ◽  
Hisayoshi Murai ◽  
Tadayuki Hirai ◽  
Hiroyuki Sugimoto ◽  
Takuto Hamaoka ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Heart Rate ◽  
Catheter Ablation ◽  
Sympathetic Nerve ◽  
High Frequency ◽  
Sympathetic Nerve Activity ◽  
Low Frequency ◽  
Frequency Component ◽  
Nerve Activity ◽  
Parasympathetic Nerve

Background/Introduction: Paroxysmal atrial fibrillation (PAF) is the most common arrhythmia and catheter ablation (CA) is selected with the aim of rhythm control. CA was reported to increase heart rate (HR), which explains the modulation on the cardiac autonomic nervous system. However, little is known about the relationship between heart rate, sympathetic nerve activity and parasympathetic nerve activity in patient with PAF. Purpose: The purpose of this study was to evaluate the effect of CA on direct recording of muscle sympathetic nerve activity (MSNA) and heart rate variability (HRV), and these influences on HR. Methods: This study was conducted as a prospective, observational study. Patients with PAF who were scheduled for CA were enrolled. We measured blood pressure, HR, body weight, brain natriuretic peptide (BNP), echocardiogram parameters, high frequency component as cardiac parasympathetic nerve activity and low frequency component as cardiac sympathetic nerve activity in HRV, and MSNA before and 12 weeks after CA. Results: 21 PAF patients participated in this study. After CA, E/e’ and Ln BNP were significantly reduced(10.6±2.9 to 9.2±2.6, p<0.05. 3.8±1.3 to 3.3±1.6 log/pg/ml, p<0.05, respectively) while no significant changes were observed in EF, SV, left atrial diameter, left ventricular end diastolic and systolic diameters. HR was significantly increased (61.3±7.8 to 71.1±7.6 beats/min, p<0.05, respectively). However, the MSNA burst incidence and frequency were significantly decreased (65.4±12.6 to 41.3±13.4 bursts/100beats, p<0.01, n=21. 39.8±8.8 to 28.1±9.6 bursts/min, p<0.01, n=21. respectively). Also, the reduction in MSNA burst frequency was correlated with the increase in HR (r=0.57, 95%CI 0.183-0.804, p=0.00702). Ln Low frequency component in HRV was significantly decreased (5.72±1.75 to 3.85±2.13 log/ms 2 , p<0.05, n=12), but Ln high frequency (HF) component was not changed . No significant relationship observed between increased HR and HF component. Conclusion: CA induced paradoxical increasing heart rate with the reduction in sympathetic nerve activity in patient with PAF. These findings suggest that CA might modulate autonomic interaction between sinus nodes and in left atrium with denervated in ganglionated plexi.

scholarly journals Functional near-infrared spectroscopy can detect low-frequency hemodynamic oscillations in the prefrontal cortex during steady-state visual evoked potential-inducing periodic facial expression stimuli presentation

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Meng-Yun Wang ◽  
Anzhe Yuan ◽  
Juan Zhang ◽  
Yutao Xiang ◽  
Zhen Yuan
Keyword(s):  
Prefrontal Cortex ◽  
Infrared Spectroscopy ◽  
Steady State ◽  
Facial Expression ◽  
Near Infrared Spectroscopy ◽  
High Frequency ◽  
Near Infrared ◽  
Low Frequency ◽  
Functional Near Infrared Spectroscopy ◽  
Visual Evoked

AbstractBrain oscillations are vital to cognitive functions, while disrupted oscillatory activity is linked to various brain disorders. Although high-frequency neural oscillations (> 1 Hz) have been extensively studied in cognition, the neural mechanisms underlying low-frequency hemodynamic oscillations (LFHO) < 1 Hz have not yet been fully explored. One way to examine oscillatory neural dynamics is to use a facial expression (FE) paradigm to induce steady-state visual evoked potentials (SSVEPs), which has been used in electroencephalography studies of high-frequency brain oscillation activity. In this study, LFHO during SSVEP-inducing periodic flickering stimuli presentation were inspected using functional near-infrared spectroscopy (fNIRS), in which hemodynamic responses in the prefrontal cortex were recorded while participants were passively viewing dynamic FEs flickering at 0.2 Hz. The fast Fourier analysis results demonstrated that the power exhibited monochronic peaks at 0.2 Hz across all channels, indicating that the periodic events successfully elicited LFHO in the prefrontal cortex. More importantly, measurement of LFHO can effectively distinguish the brain activation difference between different cognitive conditions, with happy FE presentation showing greater LFHO power than neutral FE presentation. These results demonstrate that stimuli flashing at a given frequency can induce LFHO in the prefrontal cortex, which provides new insights into the cognitive mechanisms involved in slow oscillation.

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