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Specialized photoreceptor composition in the raptor fovea

The retinae of many bird species contain a depression with high photoreceptor density known as the fovea. Many species of raptors have two foveae, a deep central fovea and a shallower temporal fovea. Birds have six types of photoreceptors: rods, active in dim light, double cones that are thought to mediate achromatic discrimination, and four types of single cones mediating color vision. To maximiz

Individual repeatability of foraging behaviour in a marine predator, the great cormorant, Phalacrocorax carbo

Intrapopulation variability, especially individual foraging specialization, has been investigated in many species. Nevertheless, the repeatability of foraging behaviour remains poorly understood. In particular, whether individuals differ in their respective degrees of repeatability still remains to be determined. Here, we estimated foraging behaviour repeatability in the great cormorant, at both t

Performance comparison of time-frequency distributions for estimation of instantaneous frequency of heart rate variability signals

The instantaneous frequency (IF) of a non-stationary signal is usually estimated from a time-frequency distribution (TFD). The IF of heart rate variability (HRV) is an important parameter because the power in a frequency band around the IF can be used for the interpretation and analysis of the respiratory rate but also for a more accurate analysis of heart rate (HR) signals. In this study, we comp

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The vision is certainly the most developed sense in raptors, and these birds are cosidered as the vertebrates with the greatest visual acuity. However, raptors are among the most frequent victims of collisions with wind turbines and other human features. Given the conservation issues and the cost of conservation operations , it is essential to understand how sensory abilities of raptor affect thei

Anatomical organization of the brain of a diurnal and a nocturnal dung beetle

To avoid the fierce competition for food, South African ball-rolling dung beetles carve a piece of dung off a dung-pile, shape it into a ball and roll it away along a straight line path. For this unidirectional exit from the busy dung pile, at night and day, the beetles use a wide repertoire of celestial compass cues. This robust and relatively easily measurable orientation behavior has made ball-

Time-resolved terahertz spectroscopy reveals the influence of charged sensitizing quantum dots on the electron dynamics in ZnO

Photoinitiated charge carrier dynamics in ZnO nanoparticles sensitized by CdSe quantum dots is studied using transient absorption spectroscopy and time-resolved terahertz spectroscopy. The evolution of the transient spectra shows that electron injection occurs in a two-step process, where the formation of a charge transfer state (occurring in several picoseconds) is followed by its dissociation wi

Studies of molecular mechanisms of telomere maintenance in Naumovozyma castellii

POPULAR SCIENTIFIC SUMMARYI was on my way home, sitting on the bus. My tired eyes swept through the pages of the local newspaper and that was the moment I met Lisa. She had previously been diagnosed with cancer. She had recovered and was back to her daily life. Unfortunately the cancer has come back and it has spread to several organs. Lisa as a mother of two kids, as a wife, as a daughter, as a sTelomeres are special DNA-protein structures that protect ends of chromosomes from being recognized as double-strand breaks. Telomeres consist of tandemly repeated units of TG-rich DNA and associate with telomere-specific proteins.When a cell replicates its chromosomes, a certain piece of DNA is lost from chromosomal ends due to the ´´ end replication problem´´. This progressive shortening of telo