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The design of artificial nestboxes for the study of secondary hole-nesting birds: a review of methodological inconsistencies and potential biases

The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents However, when comparing results ac

Decomposing health: tolerance and resistance to parasites in animals.

Plant biologists have long recognized that host defence against parasites and pathogens can be divided into two conceptually different components: the ability to limit parasite burden (resistance) and the ability to limit the harm caused by a given burden (tolerance). Together these two components determine how well a host is protected against the effects of parasitism. This distinction is useful

Snakes and perturbed random walks

We study some properties of random walks perturbed at extrema, which are generalizations of the walks considered, e.g., by Davis (1999) and Tth (1996). This process can also be viewed as a version of an excited random walk, recently studied by many authors. We obtain several properties related to the range of the process with infinite memory and prove the strong law, the central limit theorem, and

Development of heart block in children of SSA/SSB-autoantibody-positive women is associated with maternal age and displays a season-of-birth pattern

Objective Congenital heart block may develop in the fetuses of Ro/SSA-positive and La/SSB-positive mothers. Recurrence rates of only 10-20% despite persisting maternal antibodies indicate that additional factors are critical for the establishment of heart block. The authors investigated the influence of other maternal and fetal factors on heart block development in a Swedish population-based cohor

Photoemission and density functional theory study of Ge(100): Clean surface and Yb-induced (2x4) reconstruction

Clean and metal-adsorbed (100) surfaces of group-IV semiconductors, such as Si and Ge, often exhibit electronically and structurally similar reconstructions. However, the fundamental bulk properties of group-IV materials can have an impact on particular features of such systems, which are related, e.g., to final-state relaxation in photoemission and thus determine their spectral line shape. Here w

Effect of pore size on the gasification of biomass char

The evolution of char porous structure can affect the gasification rate of biomass char. A model based on the classical capillary pores is developed taking into account different conversion rates for pores having different radii. The contribution of different pores with different radii is taken into account using an effectiveness factor presented for each pore radius. As the char conversion procee

Cortical Bone Histomorphometry in Male Femoral Neck: The Investigation of Age-Association and Regional Differences

Low bone volume and changes in bone quality or microarchitecture may predispose individuals to fragility fractures. As the dominant component of the human skeleton, cortical bone plays a key role in protecting bones from fracture. However, histological investigations of the underlying structural changes, which might predispose to fracture, have been largely limited to the cancellous bone. The aim

A harbor seal can transfer the same/different concept to new stimulus dimensions

We investigated the formation of an abstract concept of same/different in a harbor seal by means of a two-item same/different task. Stimuli were presented on a TFT monitor. The subject was trained to respond according to whether two horizontally aligned white shapes presented on a black background were the same, or different from each other, by giving a no-go or go response. Training comprised of

Exosomes from human mesenchymal stem cells conduct aerobic metabolism in term and preterm newborn infants

Exosomes are secreted nanovesicles that are able to transfer RNA and proteins to target cells. The emerging role of mesenchymal stem cell (MSC) exosomes as promoters of aerobic ATP synthesis restoration in damaged cells, prompted us to assess whether they contain an extramitochondrial aerobic respiration capacity. Exosomes were isolated from culture medium of human MSC from umbilical cord of ≥37-w

Cranial Osteology Of The Giant Mosasaur Plesiotylosaurus (Squamata, Mosasauridae)

Based on the type material and a new, virtually intact skull from the mid-Maastrichtian pail (probably Tierra Loma Shale) of the Moreno Formation, San Joaquin Valley, central California, the cranial osteology of the enigmatic mosasaurine Plesiotylosaurus crassidens (Squamata, Mosasauridae) is here described in detail. Plesiotylosaurus is characterized by a protruding rostrum on the snout and mandi

Photoinduced Charge Carrier Dynamics of Zn-Porphyrin-TiO(2) Electrodes: The Key Role of Charge Recombination for Solar Cell Performance (†).

Time resolved absorption spectroscopy has been used to study photoinduced electron injection and charge recombination in Zn-porphyrin sensitized nanostructured TiO(2) electrodes. The electron transfer dynamics is correlated to the performance of dye sensitized solar cells based on the same electrodes. We find that the dye/semiconductor binding can be described with a heterogeneous geometry where t

Alcohol consumption patterns, diet and body weight in 10 European countries

Background/objectives: Europe has the highest level of alcohol consumption in the world. As drinking patterns are important determinants of the beneficial and harmful effects of alcohol consumption, we investigated alcohol consumption in relation to nutrient intake, place of consumption, education and body weight in a sample of adults from 10 European countries. Methods: A 24-h dietary recall inte

Enlightened: The art of finger reading

For some forty years the eye-tracking technology has facilitated the study of eye movement patterns for sighted people during reading and other visual activities. Today – a newly developed automatic finger tracking system makes it possible to reconstruct blind people’s tactile reading in real time and to automatically analyze finger movements during Braille text reading and tactile picture recogni

Genome-wide association study identifies three loci associated with melanoma risk

We report a genome-wide association study of melanoma conducted by the GenoMEL consortium based on 317K tagging SNPs for 1,650 selected cases and 4,336 controls, with replication in an additional two cohorts (1,149 selected cases and 964 controls from GenoMEL, and a population-based case-control study in Leeds of 1,163 cases and 903 controls). The genome-wide screen identified five loci with genot