scholarly journals Ambulatory Electrocardiographic Monitoring and Ectopic Beat Detection in Conscious Mice

Sensors ◽  
2020 ◽  
Vol 20 (14) ◽  
pp. 3867
Author(s):  
Felke Steijns ◽  
Máté I. Tóth ◽  
Anthony Demolder ◽  
Lars E. Larsen ◽  
Jana Desloovere ◽  
...  
Keyword(s):  
Heart Rate ◽  
Mouse Models ◽  
Ectopic Beat ◽  
Electrocardiographic Monitoring ◽  
Ambulatory Electrocardiography ◽  
Ectopic Beats ◽  
Great Relevance ◽  
Automated Algorithms ◽  
Set Up

Ambulatory electrocardiography (AECG) is a primary diagnostic tool in patients with potential arrhythmic disorders. To study the pathophysiological mechanisms of arrhythmic disorders, mouse models are widely implemented. The use of a technique similar to AECG for mice is thus of great relevance. We have optimized a protocol which allows qualitative, long-term ECG data recording in conscious, freely moving mice. Automated algorithms were developed to efficiently process the large amount of data and calculate the average heart rate (HR), the mean peak-to-peak interval and heart rate variability (HRV) based on peak detection. Ectopic beats are automatically detected based on aberrant peak intervals. As we have incorporated a multiple lead configuration in our ECG set-up, the nature and origin of the suggested ectopic beats can be analyzed in detail. The protocol and analysis tools presented here are promising tools for studies which require detailed, long-term ECG characterization in mouse models with potential arrhythmic disorders.

Respiratory and Circulatory Changes in the Lobster (Homarus Vulgaris) During Long Term Exposure to Moderate Hypoxia

1978 ◽  
Vol 73 (1) ◽  
pp. 131-146 ◽  
Author(s):  
P. J. BUTLER ◽  
E. W. TAYLOR ◽  
B. R. MCMAHON
Keyword(s):  
Heart Rate ◽  
Oxygen Uptake ◽  
Heart Beat ◽  
Initial Increase ◽  
Experimental Chamber ◽  
Moderate Hypoxia ◽  
Subsequent Exposure ◽  
Percentage Extraction ◽  
Set Up

1. Within a few hours of the lobsters being placed in the experimental chamber in normoxic water (Po2, 130-135 mmHg), their heart rate, oxygen uptake (Vo2) and ventilation volume (Vu) were relatively high. The scaphognathites were simultaneously active on both sides (bilateral ventilation) for 50% of the time, active on one side only (unilateral ventilation) for 32% of the time and simultaneously inactive (respiratory pause) for 18% of the time. Percentage extraction of O2 (% Ext.) was relatively low. 48h after having been set up, heart rate, VO2 and Vg had decreased significantly, % Ext. had increased and bilateral ventilation occupied 25% of the time. Heart rate was low and the beat irregular. 2. Upon subsequent exposure to hypoxia (PO2, 50-55 mmHg), Pa, O2, fell, there was initial hyperventilation, bilateral ventilation for 89% of the time, heart beat was more regular but Vo2 did not change significantly. An initial increase in pHa caused the O2 affinity of the Hey to rise. After 72h exposure to hypoxia Vg and pHa had declined, but Vg was still higher than at the end of the period of normoxia. Blood lactate, Vo2 and % Ext. were not significantly different from the values recorded after 48 h in normoxic water. Upon return to normoxic water, Vg and the time the animals spent ventilating both branchial chambers fell, but Vo2 increased. 3. It is concluded that for settled lobsters, Vo2 could be maintained during moderate hypoxia by increasing Vg maintaining a regular heart beat, and at least initially by increasing the O2 affinity of the Hey.

Preoperative Dipyridamole Thallium Imaging and Ambulatory Electrocardiographic Monitoring as a Predictor of Perioperative Cardiac Events and Long-term Outcome

1995 ◽  
Vol 83 (5) ◽  
pp. 906-917 ◽  
Author(s):  
Lee A. Fleisher ◽  
Stanley H. Rosenbaum ◽  
Ann H. Nelson ◽  
Diwaker Jain ◽  
Frans J. Th Wackers ◽  
...  
Keyword(s):  
Cardiac Events ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Cardiac Morbidity ◽  
Electrocardiographic Monitoring ◽  
Ambulatory Electrocardiography ◽  
Thallium Imaging ◽  
Dipyridamole Thallium ◽  
Long Term Mortality

Abstract Background Dipyridamole thallium imaging (DTI) and ambulatory electrocardiography (AEGC) have been advocated as means to stratify risk before vascular surgery. The purpose of this study was to compare the predictive value of both tests in noncardiac surgery patients for perioperative cardiac morbidity and long-term mortality.

Effect of heart rate on long-term mortality among men and women

2007 ◽  
Vol 62 (3) ◽  
pp. 271-275 ◽  
Author(s):  
H. THEOBALD ◽  
P.E. WÄNDELL
Keyword(s):  
Heart Rate ◽  
Men And Women ◽  
Long Term Mortality

Populism and Liberal Democracy

2019 ◽  
Author(s):  
Takis S. Pappas
Keyword(s):  
United States ◽  
Liberal Democracy ◽  
The United States ◽  
Comprehensive Theory ◽  
The People ◽  
Original Definition ◽  
Key Issues ◽  
Great Relevance ◽  
Definition Of

Based on an original definition of modern populism as “democratic illiberalism” and many years of meticulous research, Takis Pappas marshals extraordinary empirical evidence from Argentina, Greece, Peru, Italy, Venezuela, Ecuador, Hungary, the United States, Spain, and Brazil to develop a comprehensive theory about populism. He addresses all key issues in the debate about populism and answers significant questions of great relevance for today’s liberal democracy, including: • What is modern populism and how can it be differentiated from comparable phenomena like nativism and autocracy? • Where in Latin America has populism become most successful? Where in Europe did it emerge first? Why did its rise to power in the United States come so late? • Is Trump a populist and, if so, could he be compared best with Venezuela’s Chávez, France’s Le Pens, or Turkey’s Erdoğan? • Why has populism thrived in post-authoritarian Greece but not in Spain? And why in Argentina and not in Brazil? • Can populism ever succeed without a charismatic leader? If not, what does leadership tell us about how to challenge populism? • Who are “the people” who vote for populist parties, how are these “made” into a group, and what is in their minds? • Is there a “populist blueprint” that all populists use when in power? And what are the long-term consequences of populist rule? • What does the expansion, and possibly solidification, of populism mean for the very nature and future of contemporary democracy? Populism and Liberal Democracy will change the ways the reader understands populism and imagines the prospects of liberal democracy.

scholarly journals Effects of disk tillage on soil condition, crop yield and weed infestation

2011 ◽  
Vol 48 (No. 1) ◽  
pp. 20-26
Author(s):  
M. Birkás ◽  
T. Szalai ◽  
C. Gyuricza ◽  
M. Gecse ◽  
K. Bordás
Keyword(s):  
Winter Wheat ◽  
Crop Yield ◽  
Field Experiments ◽  
Soil Layer ◽  
Soil Condition ◽  
Perennial Weeds ◽  
Weed Infestation ◽  
Set Up ◽  
Different Levels

This research was instigated by the fact that during the last decade annually repeated shallow disk tillage on the same field became frequent practice in Hungary. In order to study the changes of soil condition associated with disk tillage and to assess it is consequences, long-term tillage field experiments with different levels of nutrients were set up in 1991 (A) and in 1994 (B) on Chromic Luvisol at Gödöllö. The effects of disk tillage (D) and disk tillage combined with loosening (LD) on soil condition, on yield of maize and winter wheat, and on weed infestation were examined. The evaluation of soil condition measured by cone index and bulk density indicated that use of disking annually resulted in a dense soil layer below the disking depth (diskpan-compaction). It was found, that soil condition deteriorated by diskpan-compaction decreased the yield of maize significantly by 20 and 42% (w/w), and that of wheat by 13 and 15% (w/w) when compared to soils with no diskpan-compaction. Averaged over seven years, and three fertilizer levels, the cover % of the total, grass and perennial weeds on loosened soils were 73, 69 and 65% of soils contained diskpan-compaction.

Long Term Effects of Low Frequency (10 Hz) Vagus Nerve Stimulation on EEG and Heart Rate Variability in Crohn's Disease: A Case Report

2014 ◽  
Vol 7 (6) ◽  
pp. 914-916 ◽  
Author(s):  
Didier Clarençon ◽  
Sonia Pellissier ◽  
Valérie Sinniger ◽  
Astrid Kibleur ◽  
Dominique Hoffman ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Crohn’S Disease ◽  
Case Report ◽  
Vagus Nerve ◽  
Nerve Stimulation ◽  
Vagus Nerve Stimulation ◽  
Low Frequency ◽  
Long Term Effects

scholarly journals Spectrum Based Power Management for Congested IoT Networks

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2681
Author(s):  
Kedir Mamo Besher ◽  
Juan Ivan Nieto-Hipolito ◽  
Raymundo Buenrostro-Mariscal ◽  
Mohammed Zamshed Ali
Keyword(s):  
Power Management ◽  
Network Performance ◽  
Channel Allocation ◽  
Battery Life ◽  
Packet Routing ◽  
Data Packets ◽  
Increasing Demand ◽  
Iot Devices ◽  
Set Up

With constantly increasing demand in connected society Internet of Things (IoT) network is frequently becoming congested. IoT sensor devices lose more power while transmitting data through congested IoT networks. Currently, in most scenarios, the distributed IoT devices in use have no effective spectrum based power management, and have no guarantee of a long term battery life while transmitting data through congested IoT networks. This puts user information at risk, which could lead to loss of important information in communication. In this paper, we studied the extra power consumed due to retransmission of IoT data packet and bad communication channel management in a congested IoT network. We propose a spectrum based power management solution that scans channel conditions when needed and utilizes the lowest congested channel for IoT packet routing. It also effectively measured power consumed in idle, connected, paging and synchronization status of a standard IoT device in a congested IoT network. In our proposed solution, a Freescale Freedom Development Board (FREDEVPLA) is used for managing channel related parameters. While supervising the congestion level and coordinating channel allocation at the FREDEVPLA level, our system configures MAC and Physical layer of IoT devices such that it provides the outstanding power utilization based on the operating network in connected mode compared to the basic IoT standard. A model has been set up and tested using freescale launchpads. Test data show that battery life of IoT devices using proposed spectrum based power management increases by at least 30% more than non-spectrum based power management methods embedded within IoT devices itself. Finally, we compared our results with the basic IoT standard, IEEE802.15.4. Furthermore, the proposed system saves lot of memory for IoT devices, improves overall IoT network performance, and above all, decrease the risk of losing data packets in communication. The detail analysis in this paper also opens up multiple avenues for further research in future use of channel scanning by FREDEVPLA board.

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