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Question: How does reproductive timing in annual social insects evolve under intraspecific exploitation competition and in response to a changing environment? The latter includes shifts in resource abundance, mortality, season length, and resource peak timing, factors often associated with climate change. Background: Climate and land use are changing. Evolutionary ecology must learn to predict how

Metal carbides have shown great promise in a wide range of applications due to their unique catalytic, electrocatalytic and magnetic properties. However, the scalable production of dispersible metal carbide nanoparticles remains a challenge. Here, we report a simple and scalable route to dispersible iron carbide (Fe3C) nanoparticles. This uses MgO nanoparticles as a removable 'cast' to synthesize

Historisk översikt över professorshemmens roll som studentbostäder under främst 1600- och 1700-talen men även med senare exempel.

We explore magnetic order in the quantum spin chain compound SrCo2V2O8 up to 14.9 T and down to 50 mK, using single-crystal neutron diffraction. Upon cooling in zero-field, commensurate antiferromagnetic (C-AFM) order with modulation vector=(0, 0, 1) develops below T N≃5.0K. Applying an external magnetic field (H∥c axis) destabilizes this C-AFM order, leading to an order-disorder transition betwee

Aim: Self-efficacy for writing is an important motivational factor and considered to predict writing performance. Self-efficacy for narrative writing has been sparsely studied, and few studies focus on the effects of writing intervention on self-efficacy. Additionally, there is a lack of validated measures of self-efficacy for elementary school students. In a previous study, we found that a traine

In spite of the fact that negation has been the focus of many studies, the way it is processed in human communication still eludes us. Previous studies of negation using event-related potentials (ERPs) have reported inconclusive results as to whether or not negation poses difficulties for processing. While some have found that negation is initially ignored and incongruities in negated sentences do

Introduction: School-based bullying is an omnipresent problem, but is less frequent when bystanders are inclined to defend victims. This makes it important to focus on motivation to intervene in bullying. Methods: 202 students (Mage=16.44 years, 52% boys) from public Swedish high schools participated in a vignette experiment. Students were randomized to one of two vignettes (victim belonging to/no

The distribution of the neuropeptides methionine‐ and leucine‐enkephalins, substance P, FMRFamide, neuropeptide Y, and vasoactive intestinal peptide, as well as the biogenic amine serotonin was studied in the optic tectum of the Atlantic salmon by means of immunocytochemistry. Peroxidase‐antiperoxidase and indirect immunofluorescence methods were used to compare the differential laminar distributi

Immunocytochemistry using antibodies against Met-enkephalin and Leu-enkephalin has demonstrated a group of large enkephalin-immunoreactive neurons in the nucleus of the rostral mesencephalic tegmentum (mRMT) of two teleost fish, Salmo gairdneri and Salmo salar. Injections of cobalt-lysine in the medial optic tectum retrogradely labeled the above group of tegmental neurons. Tegmental neurons were l

A parapineal organ was found to be present in 21 teleost fishes belonging to 20 different families, but was absent in poecilids and cyprinodontids. The parapineal organ was situated on the left side of the brain and sent a nerve tract to the left habenular nucleus, except in Gadus, where a “parapineal organ” appeared to send a nerve tract into the pineal stalk. The parapineal organ of adult Gaster

With the aid of specific antisera to the retinal proteins S‐antigen and α‐transducin and to the rhodopsin apoprotein opsin, we have labeled various cell populations in the pineal organ, parapineal organ, habenular nucleus, and subcommissural organ in two teleost species: the rainbow trout and the European minnow. Although these proteins are associated with photoreceptor functions, not only photore

A key task in the ESMERALDA project dealt with identifying appropriate case studies to test the ‘flexible methodology’ in its different stages of development. Case studies consist of working examples in which mapping and assessment of ecosystem services were applied to address specific decision-making problems. Testing is understood as an iterative process of co-learning that involves project part

Under lång tid var Ingemar Ståhl en välkänd nationalekonom i vårt land. Han presenterade nya perspektiv inom forskning, debatt och undervisning. På områ- den som bostäder, försvarsekonomi, energipolitik, finansiell ekonomi, industri- politik, högre utbildning, löntagarfonder, rättsekonomi, sjukvårdsekonomi och skatter lämnade han avtryck. Han förespråkade ett public choice-perspektiv, vilket han a

The minimum weighted edge dominating set problem (MWEDS) generalizes both the weighted vertex cover problem and the problem of covering the edges of graph by a minimum cost set of both vertices and edges. In this paper, we propose a meta heuristic approach based on genetic algorithm and local search to solve the MWEDS problem. Therefore, the proposed method is considered as a memetic search algori

The role of developmental bias and plasticity in evolution is a central research interest in evolutionary biology. Studies of these concepts and related processes are usually conducted on extant systems and have seen limited investigation in the fossil record. Here, I identify plasticity-led evolution (PLE) as a form of developmental bias accessible through scrutiny of paleontological material. I

Most giant exoplanets discovered by radial velocity surveys have much higher eccentricities than those in the solar system. The planet-planet scattering mechanism has been shown to match the broad eccentricity distribution, but the highest-eccentricity planets are often attributed to Kozai-Lidov oscillations induced by a stellar companion. Here we investigate whether the highly eccentric exoplanet