scholarly journals Strong Early Phase Parasympathetic Inhibition Followed by Sympathetic Withdrawal During Propofol Induction: Temporal Response Assessed by Wavelet-Based Spectral Analysis and Photoplethysmography

2021 ◽  
Vol 12 ◽  
Author(s):  
Hsin-Yi Wang ◽  
Men-Tzung Lo ◽  
Kun-Hui Chen ◽  
Susan Mandell ◽  
Wen-Kuei Chang ◽  
...  

Background: Induction of anesthesia with propofol is associated with a disturbance in hemodynamics, in part due to its effects on parasympathetic and sympathetic tone. The impact of propofol on autonomic function is unclear. In this study, we investigated in detail the changes in the cardiac autonomic nervous system (ANS) and peripheral sympathetic outflow that occur during the induction of anesthesia.Methods: Electrocardiography and pulse photoplethysmography (PPG) signals were recorded and analyzed from 30 s before to 120 s after propofol induction. The spectrogram was derived by continuous wavelet transform with the power of instantaneous high-frequency (HFi) and low-frequency (LFi) bands extracted at 1-s intervals. The wavelet-based parameters were then divided into the following segments: (1) baseline (30 s before administration of propofol), (2) early phase (first minute after administration of propofol), and (3) late phase (second minute after administration of propofol) and compared with the same time intervals of the Fourier-based spectrum [high-frequency (HF) and low-frequency (LF) bands]. Time-dependent effects were explored using fractional polynomials and repeated-measures analysis of variance.Results: Administration of propofol resulted in reductions in HFi and LFi and increases in the LFi/HFi ratio and PPG amplitude, which had a significant non-linear relationship. Significant between-group differences were found in the HFi, LFi, and LFi/HFi ratio and Fourier-based HF and LF after dividing the segments into baseline and early/late phases. On post hoc analysis, changes in HFi, LFi, and the LFi/HFi ratio were significant starting from the early phase. The corresponding effect size (partial eta squared) was > 0.3, achieving power over 90%; however, significant decreases in HF and LF were observed only in the late phase. The PPG amplitude was increased significantly in both the early and late phases.Conclusion: Propofol induction results in significant immediate changes in ANS activity that include temporally relative elevation of cardiac sympathovagal balance and reduced sympathetic activity.Clinical Trial Registration: The study was approved by the Institutional Review Board of Taipei Veterans General Hospital (No. 2017-07-009CC) and is registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT03613961).

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 794
Author(s):  
Marco Aurelio Sartim ◽  
Camila O. S. Souza ◽  
Cassiano Ricardo A. F. Diniz ◽  
Vanessa M. B. da Fonseca ◽  
Lucas O. Sousa ◽  
...  

Respiratory compromise in Crotalus durissus terrificus (C.d.t.) snakebite is an important pathological condition. Considering that crotoxin (CTX), a phospholipase A2 from C.d.t. venom, is the main component of the venom, the present work investigated the toxin effects on respiratory failure. Lung mechanics, morphology and soluble markers were evaluated from Swiss male mice, and mechanism determined using drugs/inhibitors of eicosanoids biosynthesis pathway and autonomic nervous system. Acute respiratory failure was observed, with an early phase (within 2 h) characterized by enhanced presence of eicosanoids, including prostaglandin E2, that accounted for the increased vascular permeability in the lung. The alterations of early phase were inhibited by indomethacin. The late phase (peaked 12 h) was marked by neutrophil infiltration, presence of pro-inflammatory cytokines/chemokines, and morphological alterations characterized by alveolar septal thickening and bronchoconstriction. In addition, lung mechanical function was impaired, with decreased lung compliance and inspiratory capacity. Hexamethonium, a nicotinic acetylcholine receptor antagonist, hampered late phase damages indicating that CTX-induced lung impairment could be associated with cholinergic transmission. The findings reported herein highlight the impact of CTX on respiratory compromise, and introduce the use of nicotinic blockers and prostanoids biosynthesis inhibitors as possible symptomatic therapy to Crotalus durissus terrificus snakebite.


Author(s):  
Dirk Kerzel ◽  
Stanislas Huynh Cong

AbstractVisual search may be disrupted by the presentation of salient, but irrelevant stimuli. To reduce the impact of salient distractors, attention may suppress their processing below baseline level. While there are many studies on the attentional suppression of distractors with features distinct from the target (e.g., a color distractor with a shape target), there is little and inconsistent evidence for attentional suppression with distractors sharing the target feature. In this study, distractor and target were temporally separated in a cue–target paradigm, where the cue was shown briefly before the target display. With target-matching cues, RTs were shorter when the cue appeared at the target location (valid cues) compared with when it appeared at a nontarget location (invalid cues). To induce attentional suppression, we presented the cue more frequently at one out of four possible target positions. We found that invalid cues appearing at the high-frequency cue position produced less interference than invalid cues appearing at a low-frequency cue position. Crucially, target processing was also impaired at the high-frequency cue position, providing strong evidence for attentional suppression of the cued location. Overall, attentional suppression of the frequent distractor location could be established through feature-based attention, suggesting that feature-based attention may guide attentional suppression just as it guides attentional enhancement.


2015 ◽  
Vol 10 (11) ◽  
pp. 94
Author(s):  
Shwu-Ing Wu ◽  
Li Chia Huang

With the booming global tourism activities, many countries around the world are actively promoting regional tourism. Thus, understanding the tourists’ needs is important in developing tourism promotion strategies. With Nanzhuang Township, Miaoli County as the case study, this paper discusses the influence of the two independent variables, the tangible physical environment and the intangible regional image, tourists’ experiential value and the feelings after tourism. This study conducted a questionnaire survey on tourists who have visited Nanzhuang Township, Miaoli County, by convenience sampling, in order to construct the model of regional experience marketing effect. A total of 743 effective samples were retrieved. After analysis by structural equation modeling (SEM), it is found that: (1) the physical environment has a positive and significant influence on the tourists’ experiential value; (2) regional image has a positive and significant influence on the tourist’s experiential value; (3) the experiential value has a positive and significant influence on satisfaction; (4) satisfaction has a positive and significant influence on trust and commitment; (5) trust has no significant influence on commitment. Regarding the two independent variables, regional image has more influence. In addition, after comparing the group models by clustering with the high and low frequency of the number of visits, it is found that there are some differences between the high frequency group and the low frequency group, where the regional image of the high frequency group has a greater influence on the experiential value and the physical environment of the low frequency group has a greater influence on the experiential value. The findings can serve as reference for the local government and the tourism operators to develop regional marketing strategies.


2010 ◽  
Vol 139-141 ◽  
pp. 2502-2505
Author(s):  
Bing Cheng Wang ◽  
Zhao Hui Ren

Simulated four different fault signals in the lab, the authors then used wavelet scalogram and amplitude spectrum to make analysis on the above four fault signals and abstract each spectrum characteristics. Wavelet scalogram was able to extract the characteristic’s frequency, show the impact components caused by rub-impact, show the beat phenomenon caused by oil whip and show the irreducible high frequency components as well as the complex low-frequency components. Amplitude spectrum was able to show the energy size distribution at various frequency bands and able to analyze and calculate the relationship between various frequency components. Thus they express the relationship between various frequency banks from a quantitative manner. Therefore, combining the wavelet scalogram and amplitude spectrum when making analysis, as they complement and verify each other, it will enhance the reliability when extract and analyze the characteristics of fault signal.


PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0249121
Author(s):  
Oriol Aspachs ◽  
Ruben Durante ◽  
Alberto Graziano ◽  
Josep Mestres ◽  
Marta Reynal-Querol ◽  
...  

Pandemics have historically had a significant impact on economic inequality. However, official inequality statistics are only available at low frequency and with considerable delay, which challenges policymakers in their objective to mitigate inequality and fine-tune public policies. We show that using data from bank records it is possible to measure economic inequality at high frequency. The approach proposed in this paper allows measuring, timely and accurately, the impact on inequality of fast-unfolding crises, like the COVID-19 pandemic. Applying this approach to data from a representative sample of over three million residents of Spain we find that, absent government intervention, inequality would have increased by almost 30% in just one month. The granularity of the data allows analyzing with great detail the sources of the increases in inequality. In the Spanish case we find that it is primarily driven by job losses and wage cuts experienced by low-wage earners. Government support, in particular extended unemployment insurance and benefits for furloughed workers, were generally effective at mitigating the increase in inequality, though less so among young people and foreign-born workers. Therefore, our approach provides knowledge on the evolution of inequality at high frequency, the effectiveness of public policies in mitigating the increase of inequality and the subgroups of the population most affected by the changes in inequality. This information is fundamental to fine-tune public policies on the wake of a fast-moving pandemic like the COVID-19.


2017 ◽  
Vol 28 (09) ◽  
pp. 799-809 ◽  
Author(s):  
Meredith Spratford ◽  
Hannah Hodson McLean ◽  
Ryan McCreery

AbstractAccess to aided high-frequency speech information is currently assessed behaviorally using recognition of plural monosyllabic words. Because of semantic and grammatical cues that support word+morpheme recognition in sentence materials, the contribution of high-frequency audibility to sentence recognition is less than that for isolated words. However, young children may not yet have the linguistic competence to take advantage of these cues. A low-predictability sentence recognition task that controls for language ability could be used to assess the impact of high-frequency audibility in a context that more closely represents how children learn language.To determine if differences exist in recognition of s/z-inflected monosyllabic words for children with normal hearing (CNH) and children who are hard of hearing (CHH) across stimuli context (presented in isolation versus embedded medially within a sentence that has low semantic and syntactic predictability) and varying levels of high-frequency audibility (4- and 8-kHz low-pass filtered for CNH and 8-kHz low-pass filtered for CHH).A prospective, cross-sectional design was used to analyze word+morpheme recognition in noise for stimuli varying in grammatical context and high-frequency audibility. Low-predictability sentence stimuli were created so that the target word+morpheme could not be predicted by semantic or syntactic cues. Electroacoustic measures of aided access to high-frequency speech sounds were used to predict individual differences in recognition for CHH.Thirty-five children, aged 5–12 yrs, were recruited to participate in the study; 24 CNH and 11 CHH (bilateral mild to severe hearing loss) who wore hearing aids (HAs). All children were native speakers of English.Monosyllabic word+morpheme recognition was measured in isolated and sentence-embedded conditions at a +10 dB signal-to-noise ratio using steady state, speech-shaped noise. Real-ear probe microphone measures of HAs were obtained for CHH. To assess the effects of high-frequency audibility on word+morpheme recognition for CNH, a repeated-measures ANOVA was used with bandwidth (8 kHz, 4 kHz) and context (isolated, sentence embedded) as within-subjects factors. To compare recognition between CNH and CHH, a mixed-model ANOVA was completed with context (isolated, sentence-embedded) as a within-subjects factor and hearing status as a between-subjects factor. Bivariate correlations between word+morpheme recognition scores and electroacoustic measures of high-frequency audibility were used to assess which measures might be sensitive to differences in perception for CHH.When high-frequency audibility was maximized, CNH and CHH had better word+morpheme recognition in the isolated condition compared with sentence-embedded. When high-frequency audibility was limited, CNH had better word+morpheme recognition in the sentence-embedded condition compared with the isolated condition. CHH whose HAs had greater high-frequency speech bandwidth, as measured by the maximum audible frequency, had better word+morpheme recognition in sentences.High-frequency audibility supports word+morpheme recognition within low-predictability sentences for both CNH and CHH. Maximum audible frequency can be used to estimate word+morpheme recognition for CHH. Low-predictability sentences that do not contain semantic or grammatical context may be of clinical use in estimating children’s use of high-frequency audibility in a manner that approximates how they learn language.


Author(s):  
Asmaa Nur Aqilah Zainal Badri ◽  
Norlaili Mohd Noh ◽  
Shukri Bin Korakkottil Kunhi Mohd ◽  
Asrulnizam Abd Manaf ◽  
Arjuna Marzuki ◽  
...  

<p>This study reviews related studies on the impact of the layout dependent effects on high frequency and RF noise parameter performances, carried out over the past decade. It specifically focuses on the doughnut and multi- finger layouts. The doughnut style involves the polygonal and the 4- sided techniques, while the multi-finger involving the narrow-oxide diffusion (OD) and multi-OD. The polygonal versus 4-sided doughnut, and the narrow-OD with multi-fingers versus multi-OD with multi- fingers are reviewed in this study. The high frequency parameters, which are of concern in this study, are the cut- off frequency (f<sub>T</sub>) and the maximum frequency (f<sub>MAX</sub>), whereas the noise parameters involved are noise resistance (R<sub>N</sub>) and the minimum noise figure (NF<sub>min</sub>). In addition, MOSFET parameters, which are affected by the layout style that in turn may contribute to the changes in these high frequency, and noise parameters are also detailed. Such parameters include transconductance (G<sub>m</sub>); gate resistance (R<sub>g</sub>); effective mobility (μ<sub>eff</sub>); and parasitic capacitances (c<sub>gg</sub> and c<sub>gd</sub>). Investigation by others has revealed that the polygonal doughnut may have a larger total area in comparison with the 4- sided doughnut. It is also found by means of this review that the multi-finger layout style with narrow-OD and high number of fingers may have the best performance in f<sub>T</sub> and f<sub>MAX</sub>, owing partly to the improvement in G<sub>m</sub>, μ<sub>eff</sub>, c<sub>gg</sub>, c<sub>gd</sub> and low frequency noise (LFN). A multi-OD with a lower number of fingers may lead to a lower performance in f<sub>T</sub> due to a lower G<sub>m</sub>. Upon comparing the doughnut and the multi-finger layout styles, the doughnuts appeared to perform better than a standard multi-finger layout for f<sub>T</sub>, f<sub>MAX</sub>, G<sub>m</sub> and μ<sub>eff</sub> but are poorer in terms of LFN. It can then be concluded that the narrow-OD multi-finger may cause the increase of c<sub>gg</sub> as the transistor becomes narrower, whereas a multi-OD multi-finger may have high R<sub>g</sub> and therefore may lead to the increase of f<sub>T</sub> and f<sub>MAX</sub> as the transistor becomes narrower. Besides, the doughnut layout style has a higher G<sub>m</sub> and f<sub>T</sub>, leading to larger μ<sub>eff</sub> from the elimination of shallow trench isolation (STI) stress.</p>


2018 ◽  
Vol 13 (2) ◽  
pp. 84-90
Author(s):  
Ismat Ara Jerin ◽  
Noorzahan Begum

The author of this article brought attention to publishers that there were errors on page 1,3,4,5 published in previous issue. These errors have been corrected to enhance credibility to readers and the whole corrected article has been published in this issue of JBSP. The online version of the original article can be found at doi:http:/ /dx.doi.org/10.3329/jbsp,v13i1.37840(http://banglajol.info/ index.php/JBSP/article/view/37840) Background: For thousands of years, Nigella sativa has been used in many countries as a spice as well as a protective and curative remedy for numerous health disorders. Nigella sativa oil (NSO) suppressed pain in animal models. Objective: To assess the effects of Nigella sativa oil on pain after single administration with three increasing doses in rat models. Methods: This experimental study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, from March 2016 to February 2017. For this, 20 (twenty) Long Evans rats (200±20) of both sexes were divided into control ( 10 ml/kg of 1% solution of Tween 20) and experimental groups (NSO 0.5, with 0.5 ml/kg NSO; NSO 1, with 1 ml/kg NSO; NSO 1.5, with 1.5 ml/kg NSO) with 5 rats in each group. To assess nociceptive pain, central analgesic system and inflammatory pain early phase (1st-5th minutes); inter phase (6th-15th minutes) and late phase (16th-60th minutes) of formalin test respectively were observed. All the agents were given intraperitoneally in a single dose just one hour before the formalin test. In all phases, total frequency of jerking and total duration of flexing and licking of right hind paw were counted after administration of subcutaneous formalin (50 mL, 2.5%) injection. Statistical analysis was done by ANOVA, followed by Bonferroni’s post hoc test. Results: In early phase, NSO significantly reduced the jerking (p ≤0.001, in all doses) and flexing and licking (p ≤0.001, in higher 2 doses). In interphase, jerking was significantly (p ≤0.01) lowered after 1.5 ml/kg of NSO but flexing and licking significantly lowered by all 3 doses (p ≤0.05, p ≤ 0.001, p≤ 0.001). In addition, in late phase jerking and flexing and licking was reduced by higher 2 doses (p ≤0.001) and all 3 doses respectively (p ≤ 0.001, in all doses). Conclusion: From this study, it may be concluded that, NSO possess analgesic effect and higher two doses were more effective than lower doses. J Bangladesh Soc Physiol. 2018, December; 13(2): 84-90


Micromachines ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 134 ◽  
Author(s):  
Qing Lu ◽  
Lixin Pang ◽  
Haoqian Huang ◽  
Chong Shen ◽  
Huiliang Cao ◽  
...  

High-G MEMS accelerometers have been widely used in monitoring natural disasters and other fields. In order to improve the performance of High-G MEMS accelerometers, a denoising method based on the combination of empirical mode decomposition (EMD) and wavelet threshold is proposed. Firstly, EMD decomposition is performed on the output of the main accelerometer to obtain the intrinsic mode function (IMF). Then, the continuous mean square error rule is used to find energy cut-off point, and then the corresponding high frequency IMF component is denoised by wavelet threshold. Finally, the processed high-frequency IMF component is superposed with the low-frequency IMF component, and the reconstructed signal is denoised signal. Experimental results show that this method integrates the advantages of EMD and wavelet threshold and can retain useful signals to the maximum extent. The impact peak and vibration characteristics are 0.003% and 0.135% of the original signal, respectively, and it reduces the noise of the original signal by 96%.


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