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Polygynous male starlings allocate parental effort according to relative hatching date

In many polygynous bird species, males allocate most of their parental effort to their primary females’ broods. There are several hypotheses that may explain this: the relative reproductive value of the brood, the energetic demand of the brood, the genetic quality of the female and the certainty of fatherhood may all be higher for the primary females’ broods. Since these parameters may covary in n

The effect of egg size and habitat on starling nestling growth and survival

In spite of the fact that hatchling size and energy reserves in birds are affected by egg size, many studies have failed to find an effect of egg size on offspring fitness. One possibility is that this is because they have been performed in areas with high food availability and that effects of egg size on offspring fitness are most apparent in areas of low food availability. To investigate this, e

Intersexual competition in a polygynous mating system

In the facultatively polygynous European starling (Sturnus vulgaris) males attract from one to four mates. Males gain by mating polygynously because they produce more offspring by doing so. This is true also genetically, since polygynous males on average father the same proportion of offspring as monogamous males. However, the marginal benefit of attracting additional mates is negatively affected

Changes of community composition at multiple trophic levels due to hunting in Nigerian tropical forest

Hunting in tropical forests decimates large mammals, and this may have direct and indirect effects on other trophic levels and lead to trophic cascades. We compared replicated sites of hunted and protected forests in southeastern Nigeria, with respect to community composition of primates, other mammals, birds, plant seedlings, and mature trees. We make predictions regarding the community compositi

Structurally coupled inversion of ERT and refraction seismic data combined with cluster-based model integration

Electrical resistivity tomography (ERT) and refraction seismics are among the most frequently used geophysical methods for site-investigations and the combined results can be very helpful to fill in the gaps between the point measurements made by traditional geotechnical methods such as Cone Penetration Test (CPT), core-drilling and geophysical borehole logging. The interpretation of the results f

Nitrogen isotope evidence for manuring of early Neolithic Funnel Beaker Culture cereals from Stensborg, Sweden

Little is known about arable agriculture in the Early Neolithic (4000–3300 cal BC, Funnel Beaker Culture) of Southern Scandinavia. Archaeobotanical material is rare and few archaeological sites have yielded more than a small number of charred cereal grains. In this short communication, we present single-entity carbon and nitrogen isotope analyses of charred cereals from Stensborg, an early Funnel

Functional study of raw and cooked blue maize flour : Starch digestibility, total phenolic content and antioxidant activity

The purpose of this study was to determine the chemical composition and antioxidant capacity of blue maize (BM) (Zea mays L.) flour and to investigate the effects of polyphenol-containing extracts and BM wholegrain flour on starch digestion under uncooked and cooked conditions; commercial white maize flour was used as control. Total phenolic content in BM flour (BMF) (164 ± 14 mg gallic acid/g of

Dynamic Holocene glacial history of St. Jonsfjorden, Svalbard

Evidence of a dynamic Holocene glacial history is preserved in the terrestrial and marine archives of St. Jonsfjorden, a small fjord-system on the west coast of Spitsbergen, Svalbard. High-resolution, remotely sensed imagery from marine and terrestrial environments was used to construct geomorphological maps that highlight an intricate glacial history of the entire fjord-system. The geomorphology

The use of molecular diagnostics to infer migration directions of Willow Warblers in the southeast Baltic

The Willow Warbler (Phylloscopus trochilus, Linnaeus, 1758) is a long distance migrant and one of the most common breeding birds in the Western Palearctic. Its migratory directions have been studied in detail in Scandinavia where a narrow migratory divide is located around 62°30′ N that separates southern SW migrating Phylloscopus t. trochilus from SSE migrating Phylloscopus t. acredula. The shape

The role of ants, birds and bats for ecosystem functions and yield in oil palm plantations

One of the world's most important and rapidly expanding crops, oil palm, is associated with low levels of biodiversity. Changes in predator communities might alter ecosystem services and subsequently sustainable management but these links have received little attention to date. Here, for the first time, we manipulated ant and flying vertebrate (birds and bats) access to oil palms in six smallholde

Improving Predictive Models of In-Stream Phosphorus Concentration Based on Nationally-Available Spatial Data Coverages

Spatial data are playing an increasingly important role in watershed science and management. Large investments have been made by government agencies to provide nationally-available spatial databases; however, their relevance and suitability for local watershed applications is largely unscrutinized. We investigated how goodness of fit and predictive accuracy of total phosphorus (TP) concentration m

Synthesis, Structure, and Thermoelectric Properties of α-Zn3Sb2 and Comparison to β-Zn13Sb10

Zn-Sb compounds (e.g., ZnSb, β-Zn13Sb10) are known to have intriguing thermoelectric properties, but studies of the Zn3Sb2 composition are largely absent. In this work, α-Zn3Sb2 was synthesized and studied via temperature-dependent synchrotron powder diffraction. The α-Zn3Sb2 phase undergoes a phase transformation to the β form at 425 °C, which is stable until melting at 590 °C. Rapid quenching wa

High-Performance Low-Cost n-Type Se-Doped Mg3Sb2-Based Zintl Compounds for Thermoelectric Application

Thermoelectric materials, capable of converting heat directly into electricity without moving parts, provide a promising solid-state solution for waste heat harvesting. However, currently available commercial thermoelectric materials PbTe and Bi2Te3 are based on tellurium, an extremely scarce and expensive element, which prohibits large scale applications. Herein, we present a systematic study on

"Supertrap" at Work: Extremely Efficient Nonradiative Recombination Channels in MAPbI3 Perovskites Revealed by Luminescence Super-Resolution Imaging and Spectroscopy

Organo-metal halide perovskites are some of the most promising materials for the new generation of low-cost photovoltaic and light-emitting devices. Their solution processability is a beneficial trait, although it leads to a spatial inhomogeneity of perovskite films with a variation of the trap state density at the nanoscale. Comprehending their properties using traditional spectroscopy therefore

Expression and phylogenetic analyses reveal paralogous lineages of putatively classical and non-classical MHC-I genes in three sparrow species (Passer)

Background: The Major Histocompatibility Complex (MHC) plays a central role in immunity and has been given considerable attention by evolutionary ecologists due to its associations with fitness-related traits. Songbirds have unusually high numbers of MHC class I (MHC-I) genes, but it is not known whether all are expressed and equally important for immune function. Classical MHC-I genes are highly

Structural Characterization of Histatin 5-Spermidine Conjugates : A Combined Experimental and Theoretical Study

Histatin 5 (Hst5) is a naturally occurring antimicrobial peptide that acts as the first line of defense against oral candidiasis. It has been shown that conjugation of the active Hst5 fragment, Hst54-15, and the polyamine spermidine (Spd) improves the candidacidal effect. Knowledge about the structure of these conjugates is, however, very limited. Thus, the aim of this study was to characterize th

β-admissibility of observation operators for hypercontractive semigroups

We prove a Weiss conjecture on (Formula presented.)-admissibility of observation operators for discrete and continuous (Formula presented.)-hypercontractive semigroups of operators, by representing them in terms of shifts on weighted Bergman spaces and using a reproducing kernel thesis for Hankel operators. Particular attention is paid to the case (Formula presented.), which corresponds to the unw

Optimal Quantum Interference Thermoelectric Heat Engine with Edge States

We show theoretically that a thermoelectric heat engine, operating exclusively due to quantum-mechanical interference, can reach optimal linear-response performance. A chiral edge state implementation of a close-to-optimal heat engine is proposed in an electronic Mach-Zehnder interferometer with a mesoscopic capacitor coupled to one arm. We demonstrate that the maximum power and corresponding effi

Linking content and technology : on the geography of innovation networks in the Bergen media cluster

This paper deals with the geography of innovation networks and analyses combinatorial knowledge dynamics from a single cluster perspective. Addressing firms in the media cluster in Bergen, Norway, we examine how and from where companies acquire and combine different types of knowledge for their innovation activities. The empirical analysis, which is based on structured interviews with 22 media com