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Rufous-collared sparrows (Zonotrichia capensis peruviensis) from valleys in the Atacama Desert of Chile, live in an extremely stable environment, and exhibit overlap in molt and reproduction, with valley-specific differences in the proportion of birds engaged in both. To better understand the mechanistic pathways underlying the timing of life-history transitions, we examined the relationships amon

Some sexually selected signals are thought to convey information about the current condition and genetic/epigenetic quality of the individual signaling, including the ability to resist parasites. However, it is unclear whether semistatic sexual signals that develop periodically and remain stable over protracted periods, such as avian breeding plumage, can relate to measures of current condition an

Parasite specialization on one or a few host species leads to a reduction in the total number of available host individuals, which may decrease transmission. However, specialists are thought to be able to compensate by increased prevalence in the host population and increased success in each individual host. Here, we use variation in host breadth among a community of avian Haemosporida to investig

Host responses to parasitism in the wild are often studied in the context of single host–parasite systems, which provide little insight into the ecological dynamics of host–parasite interactions within a community. Here we characterized immune system responses to mostly low-intensity, chronic infection by haemosporidian parasites in a sample of 424 individuals of 22 avian host species from the sam

The high avian biodiversity present in the Neotropical region offers a great opportunity to explore the ecology of host-parasite relationships. We present a survey of avian haemoparasites in a megadiverse country and explore how parasite prevalences are related to physical and ecological host characteristics. Using light microscopy, we documented the presence of haemoparasites in over 2000 individ

Previous studies show that most birds inhabiting temperate regions have well defined life history stages, and they modulate the production of testosterone (T) and corticosterone (CORT) in response to changes in seasonality. In this study we aimed to examine baseline and stress-induced levels of CORT and circulating T in relation with life history stages in the rufous-collared sparrow, Zonotrichia

We tested one of the foundational hypotheses of the field of ecological immunology: that it is difficult for animals to simultaneously carry out two or more especially demanding physiological processes at optimal levels because of energy needs or other factors that cause tradeoffs among competing components of life history. We investigated possible effects of molt (a costly life-history stage that

Knowing the extent to which the acoustic structure of songs is temporally stable is essential to understanding how cultural evolution affects song dialects in oscines. The acoustic structure of the most prevalent variant of the flight-whistle song recorded from male Brown-headed Cowbirds (Molothrus ater) in the Mammoth dialect (Mammoth Lakes, California) from 2005 to 2009 differed significantly an

Public–Private Partnerships (PPPs) constitute a crucial vehicle in delivering infrastructure. In the transport sector the primary project sponsors are construction companies, which over the last few decades have transformed to strong international actors. In order to study growth strategies stemming from the PPP agreement, a conceptual game theoretic model built on four institutional rationalitiesPublic–Private Partnerships (PPPs) constitute a crucial vehicle in delivering infrastructure. In the transport sector the primary project sponsors are construction companies, which over the last few decades have transformed to strong international actors. In order to study growth strategies stemming from the PPP agreement, a conceptual game theoretic model built on four institutional rationalities

Background Sarcopenia and poor physical function are common in patients with chronic kidney disease (CKD). Our aim was to investigate the relationships between muscle mass and measured glomerular filtration rate (GFR) and between muscle mass and strength and balance, respectively, in patients with CKD stages 3–5. Methods This is a baseline data analysis of a randomized controlled clinical trial.

Forested countries in the global south that have agreed to engage in REDD+, a policy mechanism for addressing climate change, are receiving support to improve laws, policies, systems and structures. As a mechanism initiated at the global level and seeking to use forests to address a global commons crisis (atmospheric carbon concentration), understanding how REDD+ translates into implementation at

We present the initial results from the development of an instantaneous multispectral microscopy technique exploiting spatially modulated light. Fluorescence from two excitation sources is recorded in a single exposure and separated in the Fourier domain.

In heterogeneous catalysis the reactions occur on the surface of a catalyst. To understand the reaction pathways, a detailed understanding on an atomic level is critical. However, the gas atmosphere surrounding the surface dictates the interaction between the surface and the gas. At low pressures this is often neglected, but as the community turns to higher pressures it becomes important to consid

Structured illumination is an imaging method most commonly employed within the field of microscopy. However, recently the technique has spread into other scientific fields, such as for combustion research, where it has revealed new measurement opportunities. This paper describes how structured illumination can be employed for spray- and combustion research and highlights some of the recent progres

We focused an intense attosecond pulse train into a neon gas target and observed Ne2+ resulting from two-photon double ionization. By modifying the photon spectrum we find that the process is dominated by the sequential ionization via the Ne+ ion.

The lack of a standardized database of eddy covariance observations has been an obstacle for data-driven estimation of terrestrial CO2 fluxes in Asia. In this study, we developed such a standardized database using 54 sites from various databases by applying consistent postprocessing for data-driven estimation of gross primary productivity (GPP) and net ecosystem CO2 exchange (NEE). Data-driven est

Long-lived coherences have been observed in various biological complexes and their origin is debated. We used polarization-controlled 2D electronic spectroscopy to reveal a photophysical process of coherence shift, explaining coherences in bacterial reaction centers.

Time-resolved XPS is used to monitor charge carrier dynamics in bare and dyesensitized ZnO nanoparticle films upon sub-bandgap excitation. Results are discussed in the context of impurity-related bandgap states and electron transfer from the chromophore.

The line shape of an absorption line from molecular oxygen enclosed in the pores of a ceramic material has been studied at different temperatures. By evaluating the line width it is feasible to extract temperature information of the gas inside porous scattering materials.