scholarly journals Vocal traits of shorebird chicks are related to body mass and sex

2022 ◽  
Author(s):  
Kristal Nicole Kostoglou ◽  
Edward H Miller ◽  
Michael A Weston ◽  
David R Wilson
Keyword(s):  
Body Mass ◽  
Frequency Modulation ◽  
Sexual Difference ◽  
Dominant Frequency ◽  
Rate Of Change ◽  
Antipredator Behaviour ◽  
Frequency Range ◽  
Time Intervals ◽  
Call Structure ◽  
Precocial Birds

Acoustic communication is critical during early life phases in precocial birds. For example, adult alarm calls can elicit antipredator behaviour in young, and chick vocalisations can communicate information to parents about chick identity, condition, location, sex, or age. We investigated whether chick calls of two species of Australian Charadriidae vary with sex or body mass. We handled Red-capped Plover Charadrius ruficapillus and Southern Masked Lapwing Vanellus miles novaehollandiae chicks for purposes of measurement, blood sampling, and banding. We opportunistically recorded their distress calls while in the hand, and analysed the calls to determine whether call structure is related to sex or body mass (a proxy for age). We measured five traits per call, plus time intervals between successive calls, for 26 plover chicks (2600 calls) and 95 lapwing chicks (6835 calls). In plovers, inter-call intervals were shorter in males and both inter-call interval and the dominant frequency range of calls decreased with increasing body mass. In lapwings, frequency modulation (computed as the range in the rate of change of the dominant frequency) was lower in male calls. The dominant frequency range of lapwing calls decreased with mass in both sexes, but the decline was greater in males, resulting in a lower dominant frequency range in males. Frequency modulation and entropy of lapwing calls also decreased with increasing body mass. Minimum dominant frequency did not change with body mass or sex in either species. Our study provides the first evidence for charadriid chicks of (a) a sexual difference in call structure and rate and (b) gradual growth-related changes in call structure and rate, across chicks. Studies on calls from a greater range of chick ages and from more species within this large and diverse family would be valuable. We provide a foundation for further studies of shorebird vocalisations during growth, which may elucidate the development and functional significance of such vocalisations.

scholarly journals One year change of knee cartilage morphology in the first release of participants from the Osteoarthritis Initiative progression subcohort: association with sex, body mass index, symptoms and radiographic osteoarthritis status

2008 ◽  
Vol 68 (5) ◽  
pp. 674-679 ◽  
Author(s):  
F Eckstein ◽  
S Maschek ◽  
W Wirth ◽  
M Hudelmaier ◽  
W Hitzl ◽  
...  
Keyword(s):  
Risk Factors ◽  
Body Mass Index ◽  
Body Mass ◽  
Statistical Significance ◽  
Weight Bearing ◽  
Rate Of Change ◽  
Cartilage Loss ◽  
Knee Oa ◽  
Symptomatic Knee ◽  
Osteoarthritis Initiative

Objective:The Osteoarthritis Initiative (OAI) is a multicentre study targeted at identifying biomarkers for evaluating the progression and risk factors of symptomatic knee OA. Here cartilage loss using 3 Tesla (3 T) MRI is analysed over 1 year in a subset of the OAI, together with its association with various risk factors.Methods:An age- and gender-stratified subsample of the OAI progression subcohort (79 women and 77 men, mean (SD) age 60.9 (9.9) years, body mass index (BMI) 30.3 (4.7)) with both frequent symptoms and radiographic OA in at least one knee was studied. Coronal FLASHwe (fast low angle shot with water excitation) MRIs of the right knee were acquired at 3 T. Seven readers segmented tibial and femoral cartilages blinded to order of acquisition. Segmentations were quality controlled by one expert.Results:The reduction in mean cartilage thickness (ThC) was greater (p = 0.004) in the medial than in the lateral compartment, greater (p = 0.001) in the medial femur (−1.9%) than in the medial tibia (−0.5%) and greater (p = 0.011) in the lateral tibia (−0.7%) than in the lateral femur (0.1%). Multifactorial analysis of variance did not reveal significant differences in the rate of change in ThC by sex, BMI, symptoms and radiographic knee OA status. Knees with Kellgren–Lawrence grade 2 or 3 and with a BMI >30 tended to display greater changes.Conclusions:In this sample of the OAI progression subcohort, the greatest, but overall very modest, rate of cartilage loss was observed in the weight-bearing medial femoral condyle. Knees with radiographic OA in obese participants showed trends towards higher rates of change than those of other participants, but these trends did not reach statistical significance.

The 1983 Liege Earthquake: Damage Distribution and Site Effects

1990 ◽  
Vol 6 (4) ◽  
pp. 713-737 ◽  
Author(s):  
D. Jongmans ◽  
M. Campillo
Keyword(s):  
Site Effects ◽  
Large Scale ◽  
Site Response ◽  
Dominant Frequency ◽  
Small Scale ◽  
Eastern United States ◽  
Frequency Range ◽  
Damage Distribution ◽  
Damage Data ◽  
The City

On November 8, 1983, a moderate magnitude (Ml=4.9) earthquake struck Liege (Belgium). A damage study has shown that site effects at different scales have played an important role in amplifying ground motion. On a large scale, the damage distribution has been determined by the presence of a large Carboniferous syncline beneath the city as shown by 2D numerical modeling. On a small scale, the main damage concentrations can be correlated with local superficial deposits which have amplified ground motions in the frequency range of buildings. A geophysical survey was carried out to measure the shear wave velocity of the different formations. Site response computations were made at numerous sites in order to estimate the possible amplification and to compare the results with the damage. It was shown that the spectral amplifications computed in the dominant frequency range of the buildings are consistent with the damage data. In very affected areas, 1D amplifications of 4 to 6 were obtained and in some cases 2D effects may have occurred. The Liege earthquake, taking place in the intraplate region of Northwestern Europe, presents a significant interest to other similar areas as the eastern United States.

scholarly journals Do small precocial birds enter torpor to conserve energy during development?

2020 ◽  
Vol 223 (21) ◽  
pp. jeb231761
Author(s):  
Yaara Aharon-Rotman ◽  
Gerhard Körtner ◽  
Chris B. Wacker ◽  
Fritz Geiser
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Surface Temperature ◽  
Heat Loss ◽  
Body Mass ◽  
Infrared Thermometer ◽  
Common Strategy ◽  
Energy Conserving ◽  
Altricial Birds ◽  
Precocial Birds

ABSTRACTPrecocial birds hatch feathered and mobile, but when they become fully endothermic soon after hatching, their heat loss is high and they may become energy depleted. These chicks could benefit from using energy-conserving torpor, which is characterised by controlled reductions of metabolism and body temperature (Tb). We investigated at what age the precocial king quail Coturnix chinensis can defend a high Tb under a mild thermal challenge and whether they can express torpor soon after achieving endothermy to overcome energetic and thermal challenges. Measurements of surface temperature (Ts) using an infrared thermometer showed that king quail chicks are partially endothermic at 2–10 days, but can defend high Tb at a body mass of ∼13 g. Two chicks expressed shallow nocturnal torpor at 14 and 17 days for 4–5 h with a reduction of metabolism by >40% and another approached the torpor threshold. Although chicks were able to rewarm endogenously from the first torpor bout, metabolism and Ts decreased again by the end of the night, but they rewarmed passively when removed from the chamber. The total metabolic rate increased with body mass. All chicks measured showed a greater reduction of nocturnal metabolism than previously reported in quails. Our data show that shallow torpor can be expressed during the early postnatal phase of quails, when thermoregulatory efficiency is still developing, but heat loss is high. We suggest that torpor may be a common strategy for overcoming challenging conditions during development in small precocial and not only altricial birds.

scholarly journals Rate of change in body mass index at different ages during childhood and adult obesity risk

2019 ◽  
Vol 14 (7) ◽  
pp. e12513 ◽  
Author(s):  
Tao Zhang ◽  
Paul K. Whelton ◽  
Bo Xi ◽  
Marie Krousel‐Wood ◽  
Lydia Bazzano ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Rate Of Change ◽  
Adult Obesity ◽  
Obesity Risk ◽  
Different Ages

HYSTERESIS EFFECTS IN SOIL MOISTURE MOVEMENT

1962 ◽  
Vol 42 (2) ◽  
pp. 247-253 ◽  
Author(s):  
W. J. Staple
Keyword(s):  
Moisture Content ◽  
Past History ◽  
Rate Of Change ◽  
Moisture Loss ◽  
Time Intervals ◽  
Moisture Movement ◽  
Wetting And Drying ◽  
The Past ◽  
History Of ◽  
Different Depths

Hysteresis was assessed by measuring the tension and moisture content of sections of soil at different time intervals during the redistribution of moisture in uniformly packed columns of Grenville silt loam. Moisture tension was measured by a null method and moisture content was measured gravimetrically.The rate of change of tension with moisture content dψ/dθ and hence the diffusivity, in the tension range 25 to 400 centimeters of water was more than twice as great for drying as for wetting. During redistribution of moisture, when both drying and wetting were involved, different ψ, vs. θ relationships existed at different depths, and the slopes dψ/dθ and diffusivities in the profile were often lower than those for either drying or wetting alone.Further work is needed to assess the importance of hysteresis on moisture movement in practical problems. It seems possible that data on hysteresis, and a knowledge of the past history of wetting and drying, may provide estimates of moisture loss and conservation in fallowed fields.

scholarly journals Is the Frequency Content of the Calls in North American Treefrogs Limited by Their Larynges?

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Marcos Gridi-Papp
Keyword(s):  
Frequency Modulation ◽  
Sound Intensity ◽  
Frequency Content ◽  
Frequency Range ◽  
Low Frequencies ◽  
High Frequencies ◽  
Mating Calls ◽  
Limited Frequency ◽  
Positive Direct ◽  
High Diversity

A high diversity of mating calls is found among frogs. The calls of most species, however, are simple, in comparison to those of mammals and birds. In order to determine if the mechanics of the larynx could explain the simplicity of treefrog calls, the larynges of euthanized males were activated with airflow. Laryngeal airflow, sound frequency, and sound intensity showed a positive direct relationship with the driving air pressure. While the natural calls of the studied species exhibit minimal frequency modulation, their larynges produced about an octave of frequency modulation in response to varying pulmonary pressure. Natural advertisement calls are produced near the higher extreme of frequency obtained in the laboratory and at a slightly higher intensity (6 dB). Natural calls also exhibit fewer harmonics than artificial ones, because the larynges were activated with the mouth of the animal open. The results revealed that treefrog larynges allow them to produce calls spanning a much greater range of frequencies than observed in nature; therefore, the simplicity of the calls is not due to a limited frequency range of laryngeal output. Low frequencies are produced at low intensities, however, and this could explain why treefrogs concentrate their calling at the high frequencies.

Experimental Evaluation of Vibration Effects Induced by Planed Railway Line on Surrounding Historic Tower

2014 ◽  
Vol 501-504 ◽  
pp. 861-866
Author(s):  
Yuan Tian ◽  
Nan Zhang ◽  
Wei Guo Yang ◽  
Jia Ming Niu
Keyword(s):  
Field Experiments ◽  
Dominant Frequency ◽  
Vibration Velocity ◽  
Vibration Source ◽  
Vibration Level ◽  
Frequency Range ◽  
Structural Vibrations ◽  
Upward Trend ◽  
Railway Line ◽  
Different Types

Using field experiments, the vibration effects of historic tower induced by planed railway line are estimated. The vibrations include the construction vibration and the traffic-induced vibration. The results show that the blasting construction leads to the significant increase in vertical velocity and acceleration. There is no difference between the background vibration of field and foundation of tower. Different types of the sites soil around the tower cause little change. Each measurement time showed an upward trend of vibration level with the increase of frequency. The closer the tower is to the vibration source, the larger the structural vibrations would be. The dominant frequency range for highway-induced vibration is 10-20Hz. For train-induced vibration, the dominant frequency range is more than 40Hz. Surface waves will result in amplification phenomenon of vibration velocity of ancient structures within a certain range.

scholarly journals Parametric profiler using a linearly frequency modulated signal.

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
V.I. Kaevitser ◽  
◽  
A.P. Krivtsov ◽  
I.V. Smolyaninov ◽  
A.V. Elbakidze ◽  
...  
Keyword(s):  
Experimental Model ◽  
Frequency Modulation ◽  
Wide Band ◽  
Linear Frequency Modulation ◽  
Frequency Range ◽  
Radio Engineering ◽  
Experimental Prototype ◽  
Chirp Signals ◽  
The Difference ◽  
Echo Sounder

At the Kotelnikov Institute of Radio Engineering and Electronics of RAS an experimental prototype of a parametric echo sounder-profiler with linear frequency modulation (LFM) of the sounding signal has been developed, manufactured and tested. Two chirp signals are emitted at frequencies of 144 kHz and 148 kHz. The difference reception frequencies have a frequency range of 1 kHz to 8 kHz. A wide band of differential frequencies is achieved by emitting two chirp signals. Laboratory and marine tests of the experimental model of the echo sounder-profiler have been carried out.

scholarly journals Electromagnetic interference of switching mode power regulator with chaotic frequency modulation

2002 ◽  
Vol 15 (1) ◽  
pp. 111-122
Author(s):  
Hei Wong ◽  
Yan Chan ◽  
Sui Wah
Keyword(s):  
Frequency Modulation ◽  
Electromagnetic Interference ◽  
Noise Level ◽  
Pulse Width Modulation ◽  
Chaotic Signal ◽  
Switching Frequency ◽  
Noise Power ◽  
Frequency Range ◽  
Switched Mode Power Supplies ◽  
Switching Mode

In this work, we propose an improved switching scheme (called chaotic frequency modulation (CFM)) for switched-mode power supplies to suppress the electromagnetic interference (EMI) noise source. The basic principle of CFM is to use a chaotic signal to modulate the switching signal so that the harmonics of noise power is distributed evenly over the whole spectrum instead of concentrated at the switching frequency. When compared with the conventional pulse width modulation (PWM) scheme, significant improvements in both conducted and radiated EMI noise levels were found with the proposed CFM method. For conducted EMI, the peak noise level was reduced by 25 dB_V. For radiated EMI, we found that the noise was found mainly in the frequency range of 30 MHz to 230 MHz and the CFM scheme would help to reduce the peak noise level in this frequency range by 22 dB_V.

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