scholarly journals Acoustic index-based models for determining time of day in long duration environmental audio recordings

2020 ◽  
Vol 117 ◽  
pp. 106524
Author(s):  
James Watkins ◽  
James Montgomery
Keyword(s):  
Time Of Day ◽  
Long Duration ◽  
Audio Recordings ◽  
Acoustic Index

scholarly journals Circadian Photoentrainment in Mice and Humans

Biology ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 180
Author(s):  
Russell G. Foster ◽  
Steven Hughes ◽  
Stuart N. Peirson
Keyword(s):  
Ganglion Cells ◽  
Light Exposure ◽  
Bright Light ◽  
Functional Expression ◽  
Time Of Day ◽  
High Irradiance ◽  
Intermittent Light ◽  
Long Duration ◽  
Light History

Light around twilight provides the primary entrainment signal for circadian rhythms. Here we review the mechanisms and responses of the mouse and human circadian systems to light. Both utilize a network of photosensitive retinal ganglion cells (pRGCs) expressing the photopigment melanopsin (OPN4). In both species action spectra and functional expression of OPN4 in vitro show that melanopsin has a λmax close to 480 nm. Anatomical findings demonstrate that there are multiple pRGC sub-types, with some evidence in mice, but little in humans, regarding their roles in regulating physiology and behavior. Studies in mice, non-human primates and humans, show that rods and cones project to and can modulate the light responses of pRGCs. Such an integration of signals enables the rods to detect dim light, the cones to detect higher light intensities and the integration of intermittent light exposure, whilst melanopsin measures bright light over extended periods of time. Although photoreceptor mechanisms are similar, sensitivity thresholds differ markedly between mice and humans. Mice can entrain to light at approximately 1 lux for a few minutes, whilst humans require light at high irradiance (>100’s lux) and of a long duration (>30 min). The basis for this difference remains unclear. As our retinal light exposure is highly dynamic, and because photoreceptor interactions are complex and difficult to model, attempts to develop evidence-based lighting to enhance human circadian entrainment are very challenging. A way forward will be to define human circadian responses to artificial and natural light in the “real world” where light intensity, duration, spectral quality, time of day, light history and age can each be assessed.

Effective word count estimation for long duration daily naturalistic audio recordings

2016 ◽  
Vol 84 ◽  
pp. 15-23 ◽  
Author(s):  
Ali Ziaei ◽  
Abhijeet Sangwan ◽  
John H.L. Hansen
Keyword(s):  
Word Count ◽  
Long Duration ◽  
Audio Recordings ◽  
Count Estimation

scholarly journals Revealing the ecological content of long-duration audio-recordings of the environment through clustering and visualisation

PLoS ONE ◽  
2018 ◽  
Vol 13 (3) ◽  
pp. e0193345 ◽  
Author(s):  
Yvonne F. Phillips ◽  
Michael Towsey ◽  
Paul Roe
Keyword(s):  
Long Duration ◽  
Audio Recordings

scholarly journals Fatigue Risk of Long-Distance Driver as the Impact of the Duration of Work

2015 ◽  
Vol 6 (3) ◽  
pp. 319
Author(s):  
Rida Zuraida
Keyword(s):  
High Risk ◽  
Working Hours ◽  
Chronic Fatigue ◽  
Time Of Day ◽  
Risk Level ◽  
Time On Task ◽  
Long Distance ◽  
City Bus ◽  
Long Duration ◽  
The Impact

Studies on the driver's fatigue, must focus on at least two things: the time-of-day that affect by circadian factors, and time-on-task. This paper discusses the risk level of driver fatigue, which generally have to drive in a long duration or more than 4 hours. The risk of fatigue was assessed using Fatigue Likelihood Scoring (FLS) by Transport Canada. Based on interviews with 24 inter-city bus drivers, 18 of the 24 drivers have a very high risk of fatigue that characterized by FLS scores greater than 20, while the rest have a high risk driver that characterized by FLS value greater than 10. A high risk of chronic fatigue that experienced by most of drivers caused by working hours which is more than 36 hours in a week, the duration of the shift of greater than 8 hours a day, lack of time off, the amount hours of driving at night, and the amount of time off.

scholarly journals Manual versus automatic identification of black-capped chickadee (Poecile atricapillus) vocalizations

2019 ◽  
Vol 2 (2) ◽  
pp. 41-42
Author(s):  
Vala Ingolfsson ◽  
Carolina Montenegro ◽  
William D. Service ◽  
Christopher B. Sturdy
Keyword(s):  
Computer Program ◽  
Time Of Day ◽  
Automatic Identification ◽  
Poecile Atricapillus ◽  
Random Subset ◽  
Audio Recordings ◽  
Acoustic Analyses ◽  
Strong Agreement

One time-consuming aspect of bioacoustic research is identifying vocalizations from long audio recordings. SongScope (version 4.1.5. Wildlife Acoustics, Inc.) is a computer program capable of developing acoustic recognizers that can identify wildlife vocalizations. The goal of the current study was to compare the effectiveness of manual identification of black-capped chickadee vocalizations to identification by SongScope recognizers. A recognizer was developed for each main chickadee vocalization by providing previously annotated audio of chickadees. Six chickadees (three male, three female) were recorded in one-hour intervals with and without anthropogenic (i.e., man-made) noise to provide a variety of samples to test the recognizer. These recordings were analyzed via the recognizer and two human coders, with an additional third coder reviewing a random subset of recordings for reliability. Strong agreement was found between the human coders, κ = 0.76, p < 0.00. Agreement between human coders and the recognizer was moderate for fee songs, κ = 0.46, p < 0.00, and strong for fee-bee songs, κ = 0.77, p < 0.00, as well as for chick-a-dee calls, κ = 0.82, p < 0.00. Results showed that male chickadees produced more tseet calls in silence and females produced more gargle calls during noise. No differences were found in vocalizations based on time of day. Our observations also suggest that the chick-a-dee recognizer was capable of identifying gargle and tseet calls along with the intended chick-a-dee calls. Overall, SongScope was effective at identifying fee-bee songs and chick-a-dee calls, but not as effective for identifying fee songs. These recognizers can allow for faster acoustic analyses (by approximately four times) and be continuously improved for greater accuracy.

DEPENDENCE OF INTEGRATED DURATION OF METEOR ECHOES ON WAVELENGTH AND SENSITIVITY

1954 ◽  
Vol 32 (7) ◽  
pp. 450-467 ◽  
Author(s):  
D. W. R. McKinley
Keyword(s):  
Short Duration ◽  
High Frequency ◽  
Time Of Day ◽  
Very High Frequency ◽  
Forward Scatter ◽  
Long Duration ◽  
Meteor Trails ◽  
Cedar Rapids ◽  
Very High

The reflecting properties of short-duration and long-duration echoes from meteor trails are examined. For short-duration echoes only, the observed relation between relative numbers and durations of meteor echoes is independent of wavelength, the time of day, or the presence of a strong shower. Integrated duration times are determined from back-scatter experiments on 9.22 m., 5.35 m., and 2.83 m., and are found to vary with the 3.5th power of the wavelength, for either short- or long-duration echoes. The integrated echo power depends on the 6th power of the wavelength. The effect of changing the equipment sensitivity is considered. The data from the back-scatter observations are used to predict the integrated duration times in the forward-scatter case, and in particular, it is shown that the results of the Cedar Rapids – Sterling very-high-frequency experiment may be explained by meteoric reflections.

scholarly journals Active learning for classifying long‐duration audio recordings of the environment

2018 ◽  
Vol 9 (9) ◽  
pp. 1948-1958 ◽  
Author(s):  
Mahnoosh Kholghi ◽  
Yvonne Phillips ◽  
Michael Towsey ◽  
Laurianne Sitbon ◽  
Paul Roe
Keyword(s):  
Active Learning ◽  
Long Duration ◽  
Audio Recordings

Peak duration of serum melatonin and short-day responses in adult Siberian hamsters

1988 ◽  
Vol 255 (5) ◽  
pp. R812-R822 ◽  
Author(s):  
T. J. Bartness ◽  
B. D. Goldman
Keyword(s):  
Total Duration ◽  
Time Of Day ◽  
The Body ◽  
Short Day ◽  
Siberian Hamsters ◽  
Long Duration ◽  
Secretion Profile ◽  
Lipid Mass ◽  
Epididymal White Adipose Tissue ◽  
Long Photoperiod

Long photoperiod-housed, adult Siberian hamsters were pinealectomized and given daily subcutaneous infusions of melatonin (MEL) to determine which characteristic of the MEL secretion profile is critical for short photoperiod-induced physiological responses. Long-duration MEL infusions (10 or 12 h) given for 5 wk elicited short-day-type responses [i.e., decreased body, testes, and epididymal white adipose tissue (EPIWAT) weights, EPIWAT lipoprotein lipase activity, carcass lipid content, and serum follicle-stimulating hormone and prolactin levels]. In contrast, short- or intermediate-duration (5 or 8 h) MEL infusions or saline infusions were without effect. Long-duration MEL infusions elicited short-day-type responses independently of both the time of day when MEL was administered and of the MEL dose if the latter was greater than or equal to 6.25 ng MEL/daily infusion. The continuity of the 10-h MEL infusions was important for triggering short-day-type responses; 10-h MEL infusions interrupted at their midpoint by 2 h of no infusion were ineffective even though dose and total duration were held constant. The body and lipid mass decreases were independent of the gonads, since castrated and gonad-intact hamsters responded similarly to the daily 10-h MEL infusions. Decreased body weight resulting from long-duration MEL infusions were never accompanied by decreased food intake. We conclude that the peak nocturnal duration of MEL is the critical parameter of the MEL secretion profile for triggering short-day-induced responses in adult Siberian hamsters.

Sign in / Sign up

Export Citation Format

Share Document