The Development of Phototaxis in the Frog (Rana Temporaria)

1963 ◽  
Vol 40 (2) ◽  
pp. 371-379
Author(s):  
W. R. A. MUNTZ
Keyword(s):  
Blue Light ◽  
Rana Temporaria ◽  
Green Light ◽  
Inhibitory Effect ◽  
Synergistic Action ◽  
Excitatory Effect ◽  
Frog Rana Temporaria ◽  
Phototactic Behaviour

1. The development of phototaxis in the frog was studied by testing the behaviour of tadpoles at different stages of their development. The development of the retina at each stage was checked from histological preparations. 2. Young tadpoles responded most strongly to green light (approx. 550 mµ). Gradually the number of responses to green light decreased, while more responses were made to blue light, and also to darkness. Adult frogs respond most strongly to blue light; light of wavelengths longer than about 510 mµ is responded to only slightly more often than darkness. 3. It was concluded that the phototactic behaviour of frogs is probably mediated by a synergistic action of the green rods and the cones, which have an excitatory effect, and which are opposed by an inhibitory effect of the red rods.

The First Record of Tesselated Snake, Natrix tesselata Laurenti, 1768 in the Central Chernozem Territory of Russia and Some Other Results of the Herpetological Research in the Upper Don

2011 ◽  
Vol 4 (2) ◽  
pp. 192-194
Author(s):  
Georgy A. Lada ◽  
V. Y. Nedosekin
Keyword(s):  
Rana Temporaria ◽  
First Record ◽  
Isolated Population ◽  
Common Frog ◽  
Northern Border ◽  
Frog Rana Temporaria ◽  
Bombina Bombina ◽  
Central Chernozem

A small isolated population of tesselated snake, Natrix tesselata was found in the Upper Don (Lipetsk Region, Russia). It is the first record of this species in the Central Chernozem Territory of Russia, which is separated from the northern border of the main range by the distance of about 200 km. An isolated population of common frog, Rana temporaria and phenetically peculiar population of fire-bellied toad, Bombina bombina are found here too. Faunistic aspect of new herpetological records is discussed.

scholarly journals Blue as an Underrated Alternative to Green: Photoplethysmographic Heartbeat Intervals Estimation under Two Temperature Conditions

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4241
Author(s):  
Evgeniia Shchelkanova ◽  
Liia Shchapova ◽  
Alexander Shchelkanov ◽  
Tomohiro Shibata
Keyword(s):  
Blue Light ◽  
Characteristic Point ◽  
Biological Effects ◽  
Green Light ◽  
Estimation Accuracy ◽  
Lower Sensitivity ◽  
Light Spectrum ◽  
Cardiovascular Parameter ◽  
Temperature Conditions ◽  
Characteristic Points

Since photoplethysmography (PPG) sensors are usually placed on open skin areas, temperature interference can be an issue. Currently, green light is the most widely used in the reflectance PPG for its relatively low artifact susceptibility. However, it has been known that hemoglobin absorption peaks at the blue part of the spectrum. Despite this fact, blue light has received little attention in the PPG field. Blue wavelengths are commonly used in phototherapy. Combining blue light-based treatments with simultaneous blue PPG acquisition could be potentially used in patients monitoring and studying the biological effects of light. Previous studies examining the PPG in blue light compared to other wavelengths employed photodetectors with inherently lower sensitivity to blue, thereby biasing the results. The present study assessed the accuracy of heartbeat intervals (HBIs) estimation from blue and green PPG signals, acquired under baseline and cold temperature conditions. Our PPG system is based on TCS3472 Color Sensor with equal sensitivity to both parts of the light spectrum to ensure unbiased comparison. The accuracy of the HBIs estimates, calculated with five characteristic points (PPG systolic peak, maximum of the first PPG derivative, maximum of the second PPG derivative, minimum of the second PPG derivative, and intersecting tangents) on both PPG signal types, was evaluated based on the electrocardiographic values. The statistical analyses demonstrated that in all cases, the HBIs estimation accuracy of blue PPG was nearly equivalent to the G PPG irrespective of the characteristic point and measurement condition. Therefore, blue PPG can be used for cardiovascular parameter acquisition. This paper is an extension of work originally presented at the 42nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

Small woods positively influence the occurrence and abundance of the common frog (Rana temporaria) in a traditional farming landscape

2015 ◽  
Vol 36 (4) ◽  
pp. 417-424 ◽  
Author(s):  
Alexandre Boissinot ◽  
Pierre Grillet ◽  
Aurélien Besnard ◽  
Olivier Lourdais
Keyword(s):  
Western Europe ◽  
Rana Temporaria ◽  
Common Frog ◽  
Traditional Farming ◽  
Critical Determinant ◽  
Southern Margin ◽  
Frog Species ◽  
Frog Rana Temporaria ◽  
The Common ◽  
Extensive Farming

Traditional farming landscape in western Europe is made of a complex mosaic of pastures, cultures, ponds and hedgerows connected with woods. Previous observations in the common frog species suggest that lowland populations are closely associated to wood cover and our aim was to test the validity of this assumption. We studied common frog occurrence and abundance in western central France (Deux-Sèvres department) close to the southern margin of lowland distribution. Our results pointed out that the proportion of woods surface around sampled areas (1 ha) was a critical determinant of common frog presence and abundance. Extensive farming, which maintains a mosaic of small woods, may provide a robust conservation tool for this species.

Some effects of superior laryngeal nerve stimulation on sympathetic preganglionic neuron firing

1979 ◽  
Vol 57 (10) ◽  
pp. 1073-1081 ◽  
Author(s):  
Urs Gerber ◽  
Canio Polosa
Keyword(s):  
Firing Pattern ◽  
Superior Laryngeal Nerve ◽  
Inhibitory Effect ◽  
Laryngeal Nerve ◽  
Depressant Effect ◽  
Excitatory Effect ◽  
Sympathetic Preganglionic Neurons ◽  
Preganglionic Neurons ◽  
Phrenic Motoneurons ◽  
Frequency Of Stimulation

Repetitive electrical stimulation of afferent fibers in the superior laryngeal nerve (SLN) evoked depressant or excitatory effects on sympathetic preganglionic neurons of the cervical trunk in Nembutal-anesthetized, paralyzed, artificially ventilated cats. The depressant effect, which consisted of suppression of the inspiration-synchronous discharge of units with such firing pattern, was obtained at low strength and frequency of stimulation (e.g. 600 mV, 30 Hz) and was absent at end-tidal CO2 values below threshold for phrenic nerve activity. The excitatory effect required higher intensity and frequency of stimulation and was CO2 independent. The depressant effect on sympathetic preganglionic neurons with inspiratory firing pattern seemed a replica of the inspiration-inhibitory effect observed on phrenic motoneurons. Hence, it could be attributed to the known inhibition by the SLN of central inspiratory activity, if it is assumed that this is a common driver for phrenic motoneurons and some sympathetic preganglionic neurons. The excitatory effect, on the other hand, appears to be due to connections of SLN afferents with sympathetic preganglionic neurons, independent of the respiratory center.

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