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A convenient setup for laser-induced fluorescence imaging of both CO and CO2 during catalytic CO oxidation

In-situ knowledge of the gas composition close to a catalyst is essential for a better understanding of the gas–surface interaction. With planar laser-induced fluorescence (PLIF), the gas distribution around an operating catalyst can be visualized with high spatial and temporal resolution, in a non-intrusive manner. We report on a convenient setup using a nanosecond YAG-Dye laser system together w

Oxidative challenges of avian migration : A comparative field study on a partial migrant

Most avian migrants alternate flight bouts, characterized by high metabolic rates, with stopovers, periods of fuel replenishment through hyperphagia. High-energy metabolism and excessive calorie intake shift the balance between damaging prooxidants and antioxidants toward the former. Hence, migration likely affects the oxidative balance of birds. Migratory flight indeed appears to cause oxidative

“I feel like I do not exist” : Adolescent Dissociative Experiences and the Importance of Trauma Type, Attachment, and Migration Background

Vissa ungdomar som upplevt potentiellt traumatiserande händelser kan utveckla dissociationssymptom. Under gynnsamma förhållanden har människor en förmåga att integrera känslor, tankar, sinnesintryck och minnen av livshändelser in i en adaptiv och sammanhängande självbild och berättelse om självet. Dissociation i samband med trauma kan beskrivas som ett sammanbrott av denna förmåga. Dissociativa upAfter experiencing potentially traumatic events (PTEs) some adolescents develop pathological dissociation. Trauma-related dissociation can be described as a break-down of the individual’s capacity to integrate emotions, thoughts, sensations, and memories about traumatic or other events into an adaptive and coherent self-image and self-narrative. Dissociative experiences (DE) include experienced lo

Neutron-skin effect in direct-photon and charged-hadron production in Pb+Pb collisions at the LHC

A well-established observation in nuclear physics is that in neutron-rich spherical nuclei the distribution of neutrons extends farther than the distribution of protons. In this work, we scrutinize the influence of this so called neutron-skin effect on the centrality dependence of high-pT direct-photon and charged-hadron production. We find that due to the estimated spatial dependence of the nucle

On the influence of heart rate and coupling interval prematurity on heart rate turbulence

Objective: Heart rate turbulence (HRT) has been successfully explored for cardiac risk stratification. While HRT is known to be influenced by the heart rate (HR) and the coupling interval (CI), nonconcordant results have been reported on how the CI influences HRT. The purpose of this study is to investigate HRT changes in terms of CI and HR by means of an especially designed protocol. Methods: A d

Evaluating the success of managed realignment for the restoration of salt marshes: Lessons from invertebrate communities

Studying successional processes and related factors in salt marshes encompasses both fundamental (community structuration) and applied (biodiversity conservation and restoration) issues. Current managed realignment projects and sites where, in the past, large storm events led to breaches in embankments create unique experimental conditions for such challenges by re-instating tidal inundation and s

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