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Body composition and migration strategies : a comparison between robins (Erithacus rubecula) from two stop-over sites in Sweden

Robins captured as passage migrants by the Baltic Sea in Sweden at Falsterbo and Ottenby Bird Observatories, respectively, differ with respect to body mass, fat load and orientation behaviour. Relatively more birds with large visual fat deposits are captured at Ottenby than at Falsterbo, but robins at Falsterbo carry more fat than robins at Ottenby. Robins with small fat loads at Ottenby probably

Oceanic navigation : Are there any feasible geomagnetic bi-coordinate combinations for albatrosses?

The possibility that albatrosses use a geomagnetic bi-coordinate map for long-distance navigation at sea was investigated by evaluating how five different geomagnetic parameters (i.e. total field intensity, horizontal and vertical field intensity, inclination and declination) vary in areas where foraging albatrosses have been recorded by satellite telemetry in the Southern Ocean. Our objective was

Hunting flight behaviour of the Eleonora's Falcon Falco eleonorae

The Eleonora's Falcon Falco eleonorae breeds on islands and islets in the Mediterranean region and feeds its young on migratory birds caught in the air. The breeding season is scheduled to coincide with the peak of bird migration. Between 12 and 20 September 1997 we measured flight tracks of falcons within a range of 4 km from their breeding cliffs on Isola di San Pietro 6 km off the south-west co

Trimethine Cyanine Dyes as NA-Sensitive Probes for Visualization of Cell Compartments in Fluorescence Microscopy

We propose symmetrical cationic trimethine cyanine dyes with β-substituents in the polymethine chain based on modified benzothiazole and benzoxazole heterocycles as probes for the detection and visualization of live and fixed cells by fluorescence microscopy. The spectral-luminescent properties of trimethine cyanines have been characterized for free dyes and in the presence of nucleic acids (NA) a

Expansion Microscopy on Saccharomyces cerevisiae

The unicellular eukaryote Saccharomyces cerevisiae is an invaluable resource for the study of basic eukaryotic cellular and molecular processes. However, its small size compared to other eukaryotic organisms the study of subcellular structures is challenging. Expansion microscopy (ExM) holds great potential to study the intracellular architecture of yeast, especially when paired with pan-labelling

Structural and biochemical insight into the mechanism of dual CpG site binding and methylation by the DNMT3A DNA methyltransferase

DNMT3A/3L heterotetramers contain two active centers binding CpG sites at 12 bp distance, however their interaction with DNA not containing this feature is unclear. Using randomized substrates, we observed preferential co-methylation of CpG sites with 6, 9 and 12 bp spacing by DNMT3A and DNMT3A/3L. Co-methylation was favored by AT bases between the 12 bp spaced CpG sites consistent with their incr

Automated AFM analysis of DNA bending reveals initial lesion sensing strategies of DNA glycosylases

Base excision repair is the dominant DNA repair pathway of chemical modifications such as deamination, oxidation, or alkylation of DNA bases, which endanger genome integrity due to their high mutagenic potential. Detection and excision of these base lesions is achieved by DNA glycosylases. To investigate the remarkably high efficiency in target site search and recognition by these enzymes, we appl

BIN2 orchestrates platelet calcium signaling in thrombosis and thrombo-inflammation

Store-operated Ca2+ entry (SOCE) is the major route of Ca2+ influx in platelets. The Ca2+ sensor stromal interaction molecule 1 (STIM1) triggers SOCE by forming punctate structures with the Ca2+ channel Orai1 and the inositol trisphosphate receptor (IP3R), thereby linking the endo-/sarcoplasmic reticulum to the plasma membrane. Here, we identified the BAR domain superfamily member bridging integra

Live-cell fluorescence imaging with extreme background suppression by plasmonic nanocoatings

Fluorescence microscopy allows specific and selective imaging of biological samples. Unfortunately, unspecific background due to auto-fluorescence, scattering, and non-ideal labeling efficiency often adversely affect imaging. Surface plasmon-coupled emission (SPCE) is known to selectively mediate fluorescence that spatially originates from regions close to the metal interface. However, SPCE combin

Enhanced Fluorescence Resonance Energy Transfer in G-Protein-Coupled Receptor Probes on Nanocoated Microscopy Coverslips

The G-protein-coupled receptor (GPCR) superfamily mediates cellular responses and communication across cellular membranes and is the largest known class of molecular targets with proven therapeutic value. For probing conformational changes of GPCRs and others in a live cell setting, fluorescence resonance energy transfer (FRET) is usually the method of choice. FRET probes often require careful lab

High-speed optical diagnostics of misfire limits in a spark-ignited heavy-duty hydrogen engine

This study investigates the ignitability of hydrogen in an optical heavy-duty SI engine. While the ignition energy of hydrogen is exceptionally low, the high load and lean mixtures used in heavy-duty hydrogen engines lead to a high gas density, resulting in a much higher breakdown voltage than in light-duty SI engines. Spark plug wear is a concern, so there is a need to minimise the spark energy w

Unfolding the Mystery of Autoimmunity : The Environmental Determinants of Diabetes in the Young (TEDDY) Study

In 2025, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health celebrates 75 years of leadership in diabetes research. The NIDDK serves people of the U.S. affected by or at risk for many chronic diseases, including diabetes and other endocrine, metabolic, and digestive disorders, by funding innovative research to develop better treatment

Ukrainian refugees and welfare deservingness: a comparative study of UK government discussions around the 2022 Ukraine Conflict and 2015 Migrant Crisis

Recent years witnessed mass migration towards Europe, from Russia's 2022 invasion of Ukraine and the 2015 Migrant Crisis linked to war in Syria. This article explores UK government discussion around these two significant crises, focussing on the challenges they present and the portrayal of refugees. It asks how far ministers' language differentiated between Ukrainians and Syrians regarding welfare

Stabilized scattering matrix formulation for 2D periodic multilayer dielectrics

This paper proposes an alternative semi-analytical Fourier modal method adapted for general periodic anisotropic gratings made of dielectrics with moderate to low index profiles corresponding to materials ranging from conventional dielectric 3D printing materials to ceramic materials. The proposed method is closely related to classical Rigorous Coupled-Wave Analysis built on scattering matrices, h

Does new public management repel talent? : findings from a choice experiment among German researchers

This paper analyses the effects of new public management governance on academics’ job choices. Based on a choice experiment carried out with faculty from a sample of Germany’s leading technical universities, we find that working environments characterized by varying levels of administrative burdens and high expectations concerning third-party funding acquisition are detrimental to self-actualizati

Cyanobacterial Argonautes and Cas4 family nucleases cooperate to interfere with invading DNA

Prokaryotic Argonaute proteins (pAgos) from the long-A clade are stand-alone immune systems that use small interfering DNA (siDNA) guides to recognize and cleave invading plasmid and virus DNA. Certain long-A pAgos are co-encoded with accessory proteins with unknown functions. Here, we show that cyanobacterial long-A pAgos act in conjunction with Argonaute-associated Cas4 family enzyme 1 (ACE1). S

Modelling light-dark regime influence on the carbon-nitrogen metabolism in a unicellular diazotrophic cyanobacterium

We propose a dynamical model depicting nitrogen (N2) fixation (diazotrophy) in a unicellular cyanobacterium, Crocosphaera watsonii, grown under light limitation and obligate diazotrophy. In this model, intracellular carbon and nitrogen are both divided into a structual pool and a storage pool. An internal pool that explicitly describes the nitrogenase enzyme is also added. The model is successfull

Bacteroides maternus sp. nov., a novel species isolated from human faeces

A novel bacterial strain, MSB163, was isolated from the stool sample of a healthy mother, 4 weeks after giving birth via vaginal delivery. Taxonomic identification tools revealed that MSB163 belongs to the genus Bacteroides, but it is distinct from any currently known species. The closest related species is Bacteroides cellulosilyticus strain BFG- 250, with an average nucleotide identity (fastANI)