scholarly journals Rhinovirus prevalence as indicator for efficacy of measures against SARS-CoV-2

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Simo Kitanovski ◽  
Gibran Horemheb-Rubio ◽  
Ortwin Adams ◽  
Barbara Gärtner ◽  
Thomas Lengauer ◽  
...  
Keyword(s):  
Respiratory Viruses ◽  
Emerging Viruses ◽  
Prevalence Data ◽  
Incidence Data ◽  
Bayes Inference ◽  
Current Prevalence ◽  
Highest Density Interval ◽  
Short Time ◽  
Short Time Delay ◽  
Better Than

Abstract Background Non-pharmaceutical measures to control the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be carefully tuned as they can impose a heavy social and economic burden. To quantify and possibly tune the efficacy of these anti-SARS-CoV-2 measures, we have devised indicators based on the abundant historic and current prevalence data from other respiratory viruses. Methods We obtained incidence data of 17 respiratory viruses from hospitalized patients and outpatients collected by 37 clinics and laboratories between 2010-2020 in Germany. With a probabilistic model for Bayes inference we quantified prevalence changes of the different viruses between months in the pre-pandemic period 2010-2019 and the corresponding months in 2020, the year of the pandemic with noninvasive measures of various degrees of stringency. Results We discovered remarkable reductions δ in rhinovirus (RV) prevalence by about 25% (95% highest density interval (HDI) [−0.35,−0.15]) in the months after the measures against SARS-CoV-2 were introduced in Germany. In the months after the measures began to ease, RV prevalence increased to low pre-pandemic levels, e.g. in August 2020 δ=−0.14 (95% HDI [−0.28,0.12]). Conclusions RV prevalence is negatively correlated with the stringency of anti-SARS-CoV-2 measures with only a short time delay. This result suggests that RV prevalence could possibly be an indicator for the efficiency for these measures. As RV is ubiquitous at higher prevalence than SARS-CoV-2 or other emerging respiratory viruses, it could reflect the efficacy of noninvasive measures better than such emerging viruses themselves with their unevenly spreading clusters.

scholarly journals Contactless Video-Based Heart Rate Monitoring of a Resting and an Anesthetized Pig

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 442
Author(s):  
Meiqing Wang ◽  
Ali Youssef ◽  
Mona Larsen ◽  
Jean-Loup Rault ◽  
Daniel Berckmans ◽  
...  
Keyword(s):  
Heart Rate ◽  
Estimation Error ◽  
Well Being ◽  
Absolute Error ◽  
Mean Value ◽  
Video Data ◽  
Window Functions ◽  
The Face ◽  
Short Time ◽  
Better Than

Heart rate (HR) is a vital bio-signal that is relatively easy to monitor with contact sensors and is related to a living organism’s state of health, stress and well-being. The objective of this study was to develop an algorithm to extract HR (in beats per minute) of an anesthetized and a resting pig from raw video data as a first step towards continuous monitoring of health and welfare of pigs. Data were obtained from two experiments, wherein the pigs were video recorded whilst wearing an electrocardiography (ECG) monitoring system as gold standard (GS). In order to develop the algorithm, this study used a bandpass filter to remove noise. Then, a short-time Fourier transform (STFT) method was tested by evaluating different window sizes and window functions to accurately identify the HR. The resulting algorithm was first tested on videos of an anesthetized pig that maintained a relatively constant HR. The GS HR measurements for the anesthetized pig had a mean value of 71.76 bpm and standard deviation (SD) of 3.57 bpm. The developed algorithm had 2.33 bpm in mean absolute error (MAE), 3.09 bpm in root mean square error (RMSE) and 67% in HR estimation error below 3.5 bpm (PE3.5). The sensitivity of the algorithm was then tested on the video of a non-anaesthetized resting pig, as an animal in this state has more fluctuations in HR than an anaesthetized pig, while motion artefacts are still minimized due to resting. The GS HR measurements for the resting pig had a mean value of 161.43 bpm and SD of 10.11 bpm. The video-extracted HR showed a performance of 4.69 bpm in MAE, 6.43 bpm in RMSE and 57% in PE3.5. The results showed that HR monitoring using only the green channel of the video signal was better than using three color channels, which reduces computing complexity. By comparing different regions of interest (ROI), the region around the abdomen was found physiologically better than the face and front leg parts. In summary, the developed algorithm based on video data has potential to be used for contactless HR measurement and may be applied on resting pigs for real-time monitoring of their health and welfare status, which is of significant interest for veterinarians and farmers.

Suppression of runaway electron generation by massive helium injection after induced disruptions on TEXTOR

2015 ◽  
Vol 81 (5) ◽  
Author(s):  
A. Lvovskiy ◽  
H. R. Koslowski ◽  
L. Zeng ◽  
Keyword(s):  
Time Delay ◽  
Runaway Electron ◽  
Critical Density ◽  
Runaway Electrons ◽  
Electron Generation ◽  
Disruption Mitigation ◽  
Order Of Magnitude ◽  
Short Time ◽  
Short Time Delay

Disruptions with runaway electron generation have been deliberately induced by injection of argon using a disruption mitigation valve. A second disruption mitigation valve has been utilised to inject varying amounts of helium after a short time delay. No generation of runaway electrons has been observed when more than a critical amount of helium has been injected no later than 5 ms after the triggering of the first valve. The required amount of helium for suppression of runaway electron generation is up to one order of magnitude lower than the critical density according to Connor & Hastie (1975) and Rosenbluth & Putvinski (1997).

scholarly journals Rapid intra-adrenal feedback regulation of glucocorticoid synthesis

2015 ◽  
Vol 12 (102) ◽  
pp. 20140875 ◽  
Author(s):  
J. J. Walker ◽  
F. Spiga ◽  
R. Gupta ◽  
Z. Zhao ◽  
S. L. Lightman ◽  
...  
Keyword(s):  
Adrenal Glands ◽  
Feedback Regulation ◽  
Feedback Mechanism ◽  
Acth Secretion ◽  
Primary Mechanism ◽  
Acth Receptor ◽  
Local Feedback ◽  
Short Time ◽  
Pituitary Adrenal Axis ◽  
Short Time Delay

The hypothalamic–pituitary–adrenal axis is a vital neuroendocrine system that regulates the secretion of glucocorticoid hormones from the adrenal glands. This system is characterized by a dynamic ultradian hormonal oscillation, and in addition is highly responsive to stressful stimuli. We have recently shown that a primary mechanism generating this ultradian rhythm is a systems-level interaction where adrenocorticotrophin hormone (ACTH) released from the pituitary stimulates the secretion of adrenal glucocorticoids, which in turn feedback at the level of the pituitary to rapidly inhibit ACTH secretion. In this study, we combine experimental physiology and mathematical modelling to investigate intra-adrenal mechanisms regulating glucocorticoid synthesis. Our modelling results suggest that glucocorticoids can inhibit their own synthesis through a very rapid (within minutes), presumably non-genomic, intra-adrenal pathway. We present further evidence for the existence of a short time delay in this intra-adrenal inhibition, and also that at the initiation of each ACTH stimulus, this local feedback mechanism is rapidly antagonized, presumably via activation of the specific ACTH receptor (MC2R) signalling pathway. This mechanism of intra-adrenal inhibition enables the gland to rapidly release glucocorticoids while at the same time preventing uncontrolled release of glucocorticoids in response to large surges in ACTH associated with stress.

Compound Finish Processes Using Burnishing and Ultrasonic Electrochemical Finishing on Hole-Wall Surface

2008 ◽  
Vol 53-54 ◽  
pp. 3-8
Author(s):  
Pai Shan Pa
Keyword(s):  
Wall Surface ◽  
Machining Time ◽  
High Rotational Speed ◽  
Hole Wall ◽  
Finishing Processes ◽  
Pulsed Direct Current ◽  
Short Time ◽  
Electrochemical Finishing ◽  
Off Time ◽  
Better Than

This study using ultrasonic energy transmitted into the electrolyte to assist in discharging of electrolytic product out of the machining gap in the compound finishing processes of electrochemical finishing and burnishing on hole-wall surface beyond traditional process of holes machining instead of conventional hand or machine polishing. The design finish-tool includes a burnishing-tool and an electrode as a hole-wall surface finish improvement that goes beyond traditional rough boring. In the experiment, the finish-tool travels across the hole-wall surface with continuous or pulsed direct current. The experimental results show that the large supply of current rating is effectively to reach the amount of the material removal and is advantageous to the finishing processes. The average effect of the ultrasonic is more better than the pulsed current while the machining time needs not to be prolonged by the off-time. The finish effect is better with a high rotational speed of the finish-tool because the dregs discharge of electrochemical finishing becomes easier and is also advantageous to the finish. The compound processes of burnishing and ultrasonic electrochemical finishing just require a short time to make the hole-wall surface smooth and bright.

scholarly journals A Restarting Strategy for Back-EMF-Based Sensorless Permanent Magnet Synchronous Machine Drive

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1818 ◽  
Author(s):  
Zih-Cing You ◽  
Sheng-Ming Yang
Keyword(s):  
Permanent Magnet ◽  
Synchronous Machine ◽  
Motor Drive ◽  
Permanent Magnet Synchronous Machine ◽  
Induced Current ◽  
Machine Drive ◽  
Voltage Vector ◽  
Current Controller ◽  
Short Time ◽  
Short Time Delay

Safely starting a spinning position sensorless controlled permanent magnet synchronous machine is difficult because the current controller does not include information regarding the motor position and speed for suppressing the back-electromotive force (EMF)-induced current. This paper presents a restarting strategy for back-EMF-based sensorless drives. In the proposed strategy, the existing back-EMF and position estimator are used and no additional algorithm or specific voltage vector injection is required. During the restarting period, the current controller is set to a particular state so that the back-EMF estimator can rapidly estimate motor voltage without using rotor position and speed. Then, this voltage is used to decouple the back-EMF of the motor in the current controller in order to suppress the induced current. After the back-EMF is decoupled from the current controller, sensorless control can be restored with the estimated position and speed. The experimental results indicated that the induced current can be suppressed within four to five sampling periods regardless of the spinning conditions. Because of the considerably short time delay, the motor drive can restart safely from various speeds and positions without causing overcurrent fault.

The Applicated Comparation of Three Signal Analytical Methods for Ocean CSEM Signature

2013 ◽  
Vol 798-799 ◽  
pp. 561-564
Author(s):  
Ji Yu Zhou ◽  
Feng Dao Zhou
Keyword(s):  
Frequency Analysis ◽  
Oil And Gas ◽  
Time Frequency Analysis ◽  
Hilbert Huang Transform ◽  
Time Frequency ◽  
Analysis Technique ◽  
Oil And Gas Resources ◽  
Concentration Degree ◽  
Short Time ◽  
Better Than

Sea is rich in oil and gas resources, the marine controlled source electromagnetic method (CSEM) is a kind of method seabed oil gas geophysical technology rising in recent years. Because of the problem of CSEM about the air wave in the shallow water, the research of time-frequnecy analysis technique is used to suppress the air wave in this paper. The basic idea is: because of the CSEM signals speed are different in the air and submarine, so the time which received by the receiving points are also different through these two kinds of ways. Using the time-frequency analysis technique and theoretical calculation, we can determine which part of the signal is spread over the ocean, so as to suppress the air wave effectively. This paper lists several methods of time-frequency analysis, such as Short-time Fourier transform, W-V distribution, Wavelet transform, Hilbert Huang transform. Through the time-frequency graph,we get the conclusion that HHT is better than others in concentration degree,and W-V distribution is better than STFT.Compared with the original signal, the time-frequency graph is the best in using Smooth Puseudo W-V Distribution.I have a detailed analysis about real case in using SPWVD at last.

Fault Diagnosis Method for Network Control Systems Applying SVM Disturbance Compensation

2013 ◽  
Vol 427-429 ◽  
pp. 1799-1802
Author(s):  
Jiao Meng ◽  
Qi Hua Xu ◽  
Lei Han
Keyword(s):  
Fault Diagnosis ◽  
Estimation Error ◽  
State Observer ◽  
Network Control ◽  
Ideal Condition ◽  
Disturbance Compensation ◽  
Network Control Systems ◽  
Diagnosis Method ◽  
Short Time ◽  
Short Time Delay

According to a network control system--NCS with short time-delay and packet loss, an state observer is designed firstly in this paper to obtain a state estimation error equation which is equivalent to an asynchronous dynamical system having event incidence constraint. Secondly, SVM is used to identify interferences of the NCS. Finally, making the identification result as compensation term adding to the state observer can make the residual only represent fault term under ideal condition and increase the robustness of NCS for interference, which can improve the fault diagnosis precision. The simulation results prove that the designed observer can diagnose faults effective and the disturbance compensation based on SVM has attained the expected effect.

Adaptive Servo Control Based on LQR for Flexible Master-Slave System

2011 ◽  
Vol 130-134 ◽  
pp. 2433-2437
Author(s):  
Bai Long Jia ◽  
Ying Liu ◽  
Yukinori Kobayashi
Keyword(s):  
Vibration Suppression ◽  
Servo Control ◽  
Slave System ◽  
Dynamics Model ◽  
Servo Controller ◽  
The Stability ◽  
Short Time ◽  
Short Time Delay ◽  
Input Torque ◽  
Master Slave System

In this study, an adaptive servo controller based on LQR is designed for flexible master-slave system (FMSS). A dynamics model, observer and servo controller based on LQR is built respectively. According to the parameter sensitive experiments, adaptive servo controller based on LQR is designed. This research focuses on the performance of rapid response and vibration suppression. Experimental results indicate that adaptive servo controller, which suppresses the saturation of the input torque to ensure the stability, has achieved short time delay and adequate vibration suppression.

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