scholarly journals Rhythmic abdominal pumping movements in praying Mantises (Insecta: Mantodea)

2019 ◽  
Vol 51 (1) ◽  
pp. 29-40
Author(s):  
Frederick R. Prete ◽  
Aaron E. Schirmer ◽  
Salim Patel ◽  
Christina Carrion ◽  
Greg M. Prete ◽  
...  
Keyword(s):  
Ecological Niche ◽  
System Organization ◽  
Low Frequency ◽  
High Amplitude ◽  
Emergent Property ◽  
Environmental Stressors ◽  
Ecological Diversity ◽  
Analysis Software ◽  
Respiratory Behavior ◽  
Very High

We analyzed the rhythmic, cyclical dorsal-ventral abdominal pumping movements of nymphal and adult Hierodula patellifera (Audinet- Serville 1839), and adult Stagmomantis carolina (Johansson 1763), Tenodera sinensis (de Saussure 1871), Miomantis paykullii (Stål 1871), and Sphodromantis lineola (Burmeister 1838) using a combination of customized video analysis software and frame-by-frame video analyses. Despite the phylogenetic and ecological diversity of these species, we found fundamental similarities in the overall, intermittent patterns of their abdominal pumping movements. In adults of all species, intermittent bouts of abdominal pumping had median durations of 64-89 sec, and were separated by intervals with median durations of 10-25 sec. Bouts began with rhythmic upward abdominal deflections of progressively increasing amplitude and frequency which were superimposed on an overall, progressive abdominal elevation. Bouts ended with 1-4 very high amplitude, low frequency upward deflections after which the abdomen returned to its horizontal (resting) position. In H. patellifera, the overall adult pattern emerged gradually during larval development. Given the diversity of the species tested, our data suggest that intermittent abdominal pumping (which has been associated with respiratory behavior in insects) may be independent of ecological niche or acute environmental stressors in mantises. Instead, our data support the hypothesis that these apparently respiratory related, intermittent abdominal pumping movements are an emergent property of the mantis central nervous system organization.

Fictive Gill and Lung Ventilation in the Pre- and Postmetamorphic Tadpole Brain Stem

1998 ◽  
Vol 80 (4) ◽  
pp. 2015-2022 ◽  
Author(s):  
C. S. Torgerson ◽  
M. J. Gdovin ◽  
J. E. Remmers
Keyword(s):  
Brain Stem ◽  
Rana Catesbeiana ◽  
Low Frequency ◽  
Lung Ventilation ◽  
High Amplitude ◽  
Spinal Nerve ◽  
Gill Ventilation ◽  
Respiratory Behavior ◽  
Spontaneously Breathing

Torgerson, C. S., M. J. Gdovin, and J. E. Remmers. Fictive gill and lung ventilation in the pre- and postmetamorphic tadpole brain stem. J. Neurophysiol. 80: 2015–2022, 1998. The pattern of efferent neural activity recorded from the isolated brain stem preparation of the tadpole Rana catesbeiana was examined to characterize fictive gill and lung ventilations during ontogeny. In vitro recordings from cranial nerve (CN) roots V, VII, and X and spinal nerve (SN) root II of premetamorphic tadpoles showed a coordinated sequence of rhythmic bursts occurring in one of two patterns, pattern1, high-frequency, low-amplitude bursts lacking corresponding activity in SN II and pattern 2, low-frequency, high-amplitude bursts with coincident bursts in SN II. These two patterns corresponded to gill and lung ventilatory burst patterns, respectively, recorded from nerve roots of decerebrate, spontaneously breathing tadpoles. Similar patterns were observed in brain stem preparations from postmetamorphic tadpoles except that they showed a greater frequency of lung bursts and they expressed fictive gill ventilation in SN II. The laryngeal branch of the vagus (Xl) displayed efferent bursts in phase with gill and lung activity, suggesting fictive glottal constriction during gill ventilation and glottal dilation during lung ventilation. The fictive gill ventilatory cycle of pre- and postmetamorphic tadpoles was characterized by a rostral to caudal sequence of CN bursts. The fictive lung ventilatory pattern in the premetamorphic animal was initiated by augmenting CN VII discharge followed by synchronous bursts in CN V, X, SN II, and Xl. By contrast, postmetamorphic patterns of fictive lung ventilation were characterized by lung burst activity in SN II that preceded burst onset in CN V and followed the lead burst in CN VII. We conclude that recruitment and timing of pattern 1 and pattern 2 rhythmic bursts recorded in vitro closely resemble that recorded during spontaneous respiratory behavior, indicating that the two patterns are the neural equivalent of gill and lung ventilation, respectively. Further, fictive gill and lung ventilatory patterns in postmetamorphic tadpoles differ in burst onset latency from premetamorphic tadpole patterns and resemble fictive oropharyngeal and pulmonary burst cycles in adult frogs.

REFLECTED AND TRANSMITTED FILTER FUNCTIONS FOR SIMPLE SUBSURFACE GEOMETRIES

Geophysics ◽  
1976 ◽  
Vol 41 (6) ◽  
pp. 1305-1317 ◽  
Author(s):  
M. Schoenberger ◽  
F. K. Levin
Keyword(s):  
Thin Layer ◽  
High Frequency ◽  
Narrow Band ◽  
Broad Band ◽  
Low Frequency ◽  
Single Layer ◽  
High Amplitude ◽  
Shadow Zone ◽  
Least Energy ◽  
Very High

A zone of sands embedded in shale acts as a filter, both in reflecting energy back to the surface and in transmitting energy to reflectors below them. For a single layer of sand, the reflection filter is periodic—reflecting no energy at some frequencies and more than either of the two individual interfaces at other frequencies. Separating the sand zone into two parts by inserting a thin layer of shale results in reflection filters which differ greatly from one another. The particular filter curve generated depends upon the location of the shale layer. A sand zone filters reflections from interfaces below the zone in a manner complementary to the reflection filter. Where the most energy is reflected, the least is transmitted; conversely, where the least energy is reflected, the most is transmitted. The models considered in this report could easily give rise to high‐amplitude reflections; but, unless the amplitudes were very high, there would be little filtering of deeper reflections. However, for very high‐amplitude reflections and narrow‐band data, little energy would be transmitted and a shadow zone would result. For very high‐amplitude shallow reflections and broad‐band data, a low‐frequency shallow reflection would cause high‐frequency deep reflections; a high‐frequency shallow reflection would cause low‐frequency deep reflections.

APPLICATION OF THE EMPIRICAL MODE DECOMPOSITION METHOD TO GROUND-ROLL NOISE ATTENUATION IN SEISMIC DATA

2013 ◽  
Vol 31 (4) ◽  
pp. 619 ◽  
Author(s):  
Luiz Eduardo Soares Ferreira ◽  
Milton José Porsani ◽  
Michelângelo G. Da Silva ◽  
Giovani Lopes Vasconcelos
Keyword(s):  
Empirical Mode Decomposition ◽  
Seismic Data ◽  
Low Frequency ◽  
High Amplitude ◽  
Seismic Line ◽  
Seismic Processing ◽  
Mode Decomposition ◽  
Ground Roll ◽  
Fortran 90 ◽  
Emd Method

ABSTRACT. Seismic processing aims to provide an adequate image of the subsurface geology. During seismic processing, the filtering of signals considered noise is of utmost importance. Among these signals is the surface rolling noise, better known as ground-roll. Ground-roll occurs mainly in land seismic data, masking reflections, and this roll has the following main features: high amplitude, low frequency and low speed. The attenuation of this noise is generally performed through so-called conventional methods using 1-D or 2-D frequency filters in the fk domain. This study uses the empirical mode decomposition (EMD) method for ground-roll attenuation. The EMD method was implemented in the programming language FORTRAN 90 and applied in the time and frequency domains. The application of this method to the processing of land seismic line 204-RL-247 in Tacutu Basin resulted in stacked seismic sections that were of similar or sometimes better quality compared with those obtained using the fk and high-pass filtering methods.Keywords: seismic processing, empirical mode decomposition, seismic data filtering, ground-roll. RESUMO. O processamento sísmico tem como principal objetivo fornecer uma imagem adequada da geologia da subsuperfície. Nas etapas do processamento sísmico a filtragem de sinais considerados como ruídos é de fundamental importância. Dentre esses ruídos encontramos o ruído de rolamento superficial, mais conhecido como ground-roll . O ground-roll ocorre principalmente em dados sísmicos terrestres, mascarando as reflexões e possui como principais características: alta amplitude, baixa frequência e baixa velocidade. A atenuação desse ruído é geralmente realizada através de métodos de filtragem ditos convencionais, que utilizam filtros de frequência 1D ou filtro 2D no domínio fk. Este trabalho utiliza o método de Decomposição em Modos Empíricos (DME) para a atenuação do ground-roll. O método DME foi implementado em linguagem de programação FORTRAN 90, e foi aplicado no domínio do tempo e da frequência. Sua aplicação no processamento da linha sísmica terrestre 204-RL-247 da Bacia do Tacutu gerou como resultados, seções sísmicas empilhadas de qualidade semelhante e por vezes melhor, quando comparadas as obtidas com os métodos de filtragem fk e passa-alta.Palavras-chave: processamento sísmico, decomposição em modos empíricos, filtragem dados sísmicos, atenuação do ground-roll.

scholarly journals 82 Struggle behavior and vocalizations of male piglets during castration

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 3-4
Author(s):  
Maria E Lou ◽  
Yuzhi Li ◽  
Beth Ventura
Keyword(s):  
Birth Weight ◽  
Acute Pain ◽  
High Frequency ◽  
Video Recording ◽  
Low Frequency ◽  
Peak Frequency ◽  
Analysis Software ◽  
Chi Square ◽  
Behavioral Indicators ◽  
Treatment Groups

Abstract Castration without the use of analgesia is routinely performed on male piglets. The objective of this study was to assess acute pain during castration through behavioral indicators. Piglets (n=88) were randomly allocated to one of two treatments: castration without the use of analgesia (C) and sham-castration (S). Within 24 hours after birth (birth weight = 1.78kg ±0.71), identical procedures were followed for both treatment groups, except sham piglets were not castrated. Struggle behavior (curl ups, leg kicks, and body flailing) and vocalizations were collected via continuous video recording as piglets received treatment from start (first application of scalpel) to end (application of iodine). Vocalization parameters (duration and peak frequency) were analyzed using the Raven Pro: Interactive Sound Analysis Software (Version 1.5). Peak frequency was defined as low (< 1000 Hz) and high (≥ 1000 Hz). Data were analyzed using the Glimmix Procedure of SAS. For struggle behavior, treatment did not affect curl up frequency. However, castrated piglets kicked more frequently than did sham piglets (C=28.8±0.9 vs. S=21.3±0.9 kicks/min; P=0.02). Additionally, 52% of castrated piglets displayed body flailing, whereas only 4.4% of sham piglets displayed the same behavior (Chi-Square = 24.2; P < 0.0001). For vocalizations, no difference was found for duration and peak frequency of low frequency calls. However, castrated piglets responded with more high frequency calls than sham piglets (C=23.6±0.3 vs. S=18.6±0.3 calls/min; P=0.04). High frequency calls tended to be of longer duration for castrated piglets (C=0.45±0.04 vs. S=0.27±0.04 sec/call; P=0.08). Results indicate that castration without the use of analgesia increased the frequency of leg kicks, body failing, and high frequency calls. This suggests that leg kicks, body flailing, and high frequency calls maybe useful behavioral indicators of acute pain in piglets.

Frequency Response Analysis of Piecewise Nonlinear Vibration Isolator

2005 ◽  
Author(s):  
Patrick Stahl ◽  
G. Nakhaie Jazar
Keyword(s):  
Low Frequency ◽  
High Amplitude ◽  
Relative Displacement ◽  
Response Analysis ◽  
Frequency Response Analysis ◽  
State Behavior ◽  
Vibration Isolators ◽  
Short Period ◽  
Secondary Suspension ◽  
Low Amplitude

Non-smooth piecewise functional isolators are smart passive vibration isolators that can provide effective isolation for high frequency/low amplitude excitation by introducing a soft primary suspension, and by preventing a high relative displacement in low frequency/high amplitude excitation by introducing a relatively damped secondary suspension. In this investigation a linear secondary suspension is attached to a nonlinear primary suspension. The primary is assumed to be nonlinear to model the inherent nonlinearities involved in real suspensions. However, the secondary suspension comes into action only during a short period of time, and in mall domain around resonance. Therefore, a linear assumption for the secondary suspension is reasonable. The dynamic behavior of the system subject to a harmonic base excitation has been analyzed utilizing the analytic results derived by applying the averaging method. The analytic results match very well in the transition between the two suspensions. A sensitivity analysis has shown the effect of varying dynamic parameters in the steady state behavior of the system.

scholarly journals The Influence ofNrf2on Cardiac Responses to Environmental Stressors

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Reuben Howden ◽  
Eva Gougian ◽  
Marcus Lawrence ◽  
Samantha Cividanes ◽  
Wesley Gladwell ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
High Frequency ◽  
Low Frequency ◽  
Therapeutic Strategies ◽  
Environmental Stressors ◽  
Total Power ◽  
Airborne Pollutants ◽  
Cardiac Responses

Nrf2protects the lung from adverse responses to oxidants, including 100% oxygen (hyperoxia) and airborne pollutants like particulate matter (PM) exposure, but the role ofNrf2on heart rate (HR) and heart rate variability (HRV) responses is not known. We hypothesized that genetic disruption ofNrf2would exacerbate murine HR and HRV responses to severe hyperoxia or moderate PM exposures.Nrf2-/-andNrf2+/+mice were instrumented for continuous ECG recording to calculate HR and HRV (low frequency (LF), high frequency (HF), and total power (TP)). Mice were then either exposed to hyperoxia for up to 72 hrs or aspirated with ultrafine PM (UF-PM). Compared to respective controls, UF-PM induced significantly greater effects on HR (P<0.001) and HF HRV (P<0.001) inNrf2-/-mice compared toNrf2+/+mice.Nrf2-/-mice tolerated hyperoxia significantly less thanNrf2+/+mice (~22 hrs;P<0.001). Reductions in HR, LF, HF, and TP HRV were also significantly greater inNrf2-/-compared toNrf2+/+mice (P<0.01). Results demonstrate thatNrf2deletion increases susceptibility to change in HR and HRV responses to environmental stressors and suggest potential therapeutic strategies to prevent cardiovascular alterations.

Study On Energy Dissipation Mechanism of an Impact Damper System

2022 ◽  
Author(s):  
Vinayaravi R ◽  
Jayaraj Kochupillai ◽  
Kumaresan D ◽  
Asraff A. K
Keyword(s):  
Energy Dissipation ◽  
Numerical Simulations ◽  
Fundamental Frequency ◽  
Low Frequency ◽  
High Amplitude ◽  
Lagrangian Multiplier ◽  
Impact Damper ◽  
Contact Algorithm ◽  
Dissipation Of Energy ◽  
Excitation Time

Abstract The objective of this paper is to investigate how higher damping is achieved by energy dissipation as high-frequency vibration due to the addition of impact mass. In an impact damper system, collision between primary and impact masses cause an exchange of momentum resulting in dissipation of energy. A numerical model is developed to study the dynamic behaviour of an impact damper system using a MDOF system with Augmented Lagrangian Multiplier contact algorithm. Mathematical modelling and numerical simulations are carried out using ANSYS FEA package. Studies are carried out for various mass ratios subjecting the system to low-frequency high amplitude excitation. Time responses obtained from numerical simulations at fundamental mode when the system is excited in the vicinity of its fundamental frequency are validated by comparing with experimental results. Magnification factor evaluated from numerical simulation results is comparable with those obtained from experimental data. The transient response obtained from numerical simulations is used to study the behaviour of first three modes of the system excited in vicinity of its fundamental frequency. It is inferred that dissipation of energy is a main reason for achieving higher damping for an impact damper system in addition to being transformed to heat, sound, and/or those required to deform a body.

Phase resetting of spontaneously beating embryonic ventricular heart cell aggregates

1986 ◽  
Vol 251 (6) ◽  
pp. H1298-H1305 ◽  
Author(s):  
M. R. Guevara ◽  
A. Shrier ◽  
L. Glass
Keyword(s):  
Action Potentials ◽  
High Amplitude ◽  
Heart Cell ◽  
Cell Aggregates ◽  
Embryonic Chick ◽  
Phase Resetting ◽  
Stimulus Amplitude ◽  
High Stimulus ◽  
Very High ◽  
Spontaneous Rhythm

The influence of isolated 20-ms duration current pulses on the spontaneous rhythm of embryonic chick ventricular heart cell aggregates was studied. A pulse could either delay or advance the time of occurrence of the next action potential, depending on whether it fell early or late in the cycle. As the stimulus amplitude was increased, the transition from delay to advance occurred over a narrower range of coupling intervals. At low-stimulus amplitudes the transition from delay to advance occurred in a smooth continuous fashion; at medium-stimulus amplitudes the transition was discontinuous; at high-stimulus amplitudes graded action potentials were seen. It was impossible to annihilate spontaneous activity in aggregates with a single stimulus. The phase-resetting response to hyperpolarizing pulses was qualitatively the reverse of that produced by depolarizing pulses. A very high-amplitude depolarizing or hyperpolarizing pulse could produce rapid repetitive activity. Theoretical aspects of these phenomena are discussed.

scholarly journals Low frequency radio counterparts of HESS J1731−347 a.k.a SNR G353.6−0.7

2017 ◽  
Vol 12 (S331) ◽  
pp. 201-205
Author(s):  
A. J. Nayana ◽  
Poonam Chandra
Keyword(s):  
Radio Emission ◽  
Radio Telescope ◽  
Supernova Remnants ◽  
Low Frequency ◽  
High Energy ◽  
Spectral Indices ◽  
Thermal Radio Emission ◽  
Very High Energy ◽  
Γ Rays ◽  
Very High

AbstractHESS J1731−347 a.k.a. SNR G353.6−0.7 is one of the five known very high energy (VHE, Energy > 0.1 TeV) shell-type supernova remnants. We carried out Giant Metrewave Radio Telescope (GMRT) observations of this TeV SNR in 1390, 610 and 325 MHz bands. We detected the 325 and 610 MHz radio counterparts of the SNR G353.6−0.7 (Nayana et al. 2017). We also determined the spectral indices of individual filaments and our values are consistent with the non-thermal radio emission. We compared the radio morphology with that of VHE emission. The peak in radio emission corresponds to the faintest feature in the VHE emission. We explain this anti-correlated emission in a possible leptonic origin of the VHE γ-rays.

Effect of Heat Treatments on the Damping Characteristics of TiNi-Based Shape Memory Alloys

2006 ◽  
Vol 319 ◽  
pp. 33-38 ◽  
Author(s):  
I. Yoshida ◽  
Kazuhiro Otsuka
Keyword(s):  
Internal Friction ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Low Frequency ◽  
Heat Treatments ◽  
Damping Capacity ◽  
Temperature Hysteresis ◽  
Temperature Spectrum ◽  
Two Peaks ◽  
Very High

Low frequency internal friction of Ti49Ni51 binary and Ti50Ni40Cu10 ternary shape memory alloys has been measured. The effect of solution and aging heat treatments on the damping property was examined. The temperature spectrum of internal friction for TiNi binary alloy consists, in general, of two peaks; one is a transition peak which is associated with the parent-martensite transformation and is rather unstable in a sense that it strongly depends on the frequency and decreases considerably when held at a constant temperature. The other one is a very high peak of the order of 10-2, which appears at around 200K. It appears both on cooling and on heating with no temperature hysteresis, and is very stable. The behavior of the peak is strongly influenced by the heat treatments. The trial of two-stage aging with a purpose of improving the damping capacity has been proved unsatisfactory. TiNiCu has a very high damping, the highest internal friction reaching 0.2, but by quenching from very high temperature, say 1373K, the damping is remarkably lowered. For the realization of high damping the quenching from a certain temperature range around 1173K seems the most preferable condition.

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