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Descriptive and experimental evidence for timing-mediated polygyny risk in a pied flycatcher Ficedula hypoleuca population

In polygynous species with biparental care, mates are often acquired in succession. Most research has focussed on the cost of polygyny in secondary females, but primary females may also suffer from reduced paternal care. The likelihood of sharing a male may be higher for early laying females, which could counteract the fitness benefits of breeding early. In this study, we use 12 years of data on p

Novel insights into the emerging roles of tRNA-derived fragments in mammalian development

ABTRACT: tRNA-derived fragments or tRFs were long considered merely degradation intermediates of full-length tRNAs; however, emerging research is highlighting unanticipated new and highly distinct functions in epigenetic control, metabolism, immune activity and stem cell fate commitment. Importantly, recent studies suggest that RNA epitranscriptomic modifications may provide an additional regulato

Stability, magnetic order, and electronic properties of ultrathin Fe3O4 nanosheets

We study the stability, magnetic order, charge segregation, and electronic properties of a novel three-layered Fe3O4 film by means of Hubbard-corrected density functional theory calculations. The stable film is predicted to consist of close-packed iron and oxygen layers, comprising a center layer with octahedrally coordinated Fe sandwiched between two layers with tetrahedrally coordinated Fe. The

Entropy-Driven Incommensurability : Chemical Pressure-Guided Polymorphism in PdBi and the Origins of Lock-In Phenomena in Modulated Systems

Incommensurate order, in which two or more mismatched periodic patterns combine to make a long-range ordered yet aperiodic structure, is emerging as a general phenomenon impacting the crystal structures of compounds ranging from alloys and nominally simple salts to organic molecules and proteins. The origins of incommensurability in these systems are often unclear, but it is commonly associated wi

von Willebrand factor D and EGF domains is an evolutionarily conserved and required feature of blastemas capable of multitissue appendage regeneration

Regenerative ability varies tremendously across species. A common feature of regeneration of appendages such as limbs, fins, antlers, and tails is the formation of a blastema-a transient structure that houses a pool of progenitor cells that can regenerate the missing tissue. We have identified the expression of von Willebrand factor D and EGF domains (vwde) as a common feature of blastemas capable

A modified caseload midwifery model for women with fear of birth, women's and midwives' experiences : A qualitative study

OBJECTIVE: Although fear of birth is common during pregnancy and childbirth, the best treatment for fear of birth in clinical care remain unclear. Strong evidence suggests that continuity models of midwifery care can benefit women and birth outcomes, though such models are rare in Sweden. Because women with fear of birth could benefit from such models, the aim of this qualitative study was to exam

Nonlinear plasmon-exciton coupling enhances sum-frequency generation from a hybrid metal/semiconductor nanostructure

The integration of metallic plasmonic nanoantennas with quantum emitters can dramatically enhance coherent harmonic generation, often resulting from the coupling of fundamental plasmonic fields to higher-energy, electronic or excitonic transitions of quantum emitters. The ultrafast optical dynamics of such hybrid plasmon–emitter systems have rarely been explored. Here, we study those dynamics by i

Plasma P-tau181 in Alzheimer’s disease : relationship to other biomarkers, differential diagnosis, neuropathology and longitudinal progression to Alzheimer’s dementia

Plasma phosphorylated tau181 (P-tau181) might be increased in Alzheimer’s disease (AD), but its usefulness for differential diagnosis and prognosis is unclear. We studied plasma P-tau181 in three cohorts, with a total of 589 individuals, including cognitively unimpaired participants and patients with mild cognitive impairment (MCI), AD dementia and non-AD neurodegenerative diseases. Plasma P-tau18

You never fake alone. Creative AI in action

Creative AI (notably GANs and VAEs) can generate convincing fakes of video footage, pictures, graphics, etc. In order to conceptualize the societal role of creative AI a new conceptual toolbox is needed. The paper provides metaphors and concepts for understanding the functioning of creative AI. It shows how the role of creative AI in relation to FAT ideals can be enriched by a dynamic and construc

Experimental and Numerical Assessment of Active Pre-chamber Ignition in Heavy Duty Natural Gas Stationary Engine

Gas engines (fuelled with CNG, LNG or Biogas) for generation of power and heat are, to this date, taking up larger shares of the market with respect to diesel engines. In order to meet the limit imposed by the TA-Luft regulations on stationary engines, lean combustion represents a viable solution for achieving lower emissions as well as efficiency levels comparable with diesel engines. Leaner mixt

Numerical study of heat transfer in gravity-driven particle flow around tubes with different shapes

In the present paper, the heat transfer of gravity-driven dense particle flow around five different shapes of tubes is numerically studied using discrete element method (DEM). The velocity vector, particle contact number, particle contact time and heat transfer coefficient of particle flow at different particle zones around the tube are carefully analyzed. The results show that the effect of tube

A Belief Propagation Algorithm for Multipath-Based SLAM

We present a simultaneous localization and mapping (SLAM) algorithm that is based on radio signals and the association of specular multipath components (MPCs) with geometric features. Especially in indoor scenarios, robust localization from radio signals is challenging due to diffuse multipath propagation, unknown MPC-feature association, and limited visibility of features. In our approach, specul

Numerical Optimization of Compression Ratio for a PPC Engine running on Methanol

Partially premixed combustion (PPC) has shown to produce high gross indicated efficiencies while yielding lower pollutant emissions, such as oxides of nitrogen and soot, than conventional diesel combustion. Gasoline fuels with a research octane number (RON) of 60-70 have been proposed as optimal for PPC as they balance the trade-off between ensuring good combustion stability at low engine loads an

Benchmarking the PreSPEC@GSI experiment for Coulex-multipolarimetry on the π(p3/2) → π(p1/2) spin-flip transition in 85Br

A first performance test of the Coulomb excitation multipolarimetry (Coulex-multipolarimetry) method is presented. It is based on a 85Br πp3/2 → πp1/2 spin-flip experiment performed as part of the PreSPEC-AGATA campaign at the GSI Helmholtzzentrum für Schwerionenforschung (GSI). Via determination of background levels around the expected 85Br excitations as well as measured 197Au excitations, an up

The Surgeon's Role in the Opioid Crisis : A Narrative Review and Call to Action

Over the past two decades, there has been a sharp rise in the use of prescription opioids. In several countries, most notably the United States, opioid-related harm has been deemed a public health crisis. As surgeons are among the most prolific prescribers of opioids, growing attention is now being paid to the role that opioids play in surgical care. While opioids may sometimes be necessary to pro

Globalization, the jobs ladder and economic mobility

Globalization affects the mix of jobs available in an economy and the rate at which workers gain skills. We develop a model in which firms differ in terms of productivity and workers differ in skills, and use the model to examine how globalization affects the wage distribution and the career path of workers as they move up the jobs ladder. We calibrate the model using many of the same parameters a

X-ray absorption spectroscopy principles and practical use in materials analysis

The X-ray Absorption Fine Structure (XAFS) with its subregions X-ray Absorption Near-edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) is a powerful tool for the structural analysis of materials, which is nowadays a standard component of research strategies in many fields. This review covers a wide range of topics related to its measurement and use: the origin of the fine