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Effects of oil and oil burn residues on seabird feathers

It is well known, that in case of oil spill, seabirds are among the groups of animals most vulnerable. Even small amounts of oil can have lethal effects by destroying the waterproofing of their plumage, leading to loss of insulation and buoyancy. In the Arctic these impacts are intensified. To protect seabirds, a rapid removal of oil is crucial and in situ burning could be an efficient method. In

Cognitive abnormalities and cerebral perfusion defects in a community-dwelling cohort of elderly men with MMSE within the normal range

Objectives: Mini Mental State Examination’s (MMSE’s) sensitivity in its upper level is questioned, hence we investigated cognitive abnormalities and defects in regional cerebral blood flow (rCBF) in elderly with MMSE scores ≥24. Methods: One hundred and four men at age 81 with MMSE scores ≥24 (mean 28.4 ± 1.7), no dementia or stroke, were examined with neuropsychological test battery, and their rC

Migration and wintering of a declining seabird, the thick-billed murre Uria lomvia, on an ocean basin scale : Conservation implications

Pelagic seabirds are exposed to an array of potential threats during the non-breeding period, and effective management of these threats on a large scale requires knowledge of which populations winter where. Thick-billed murres (Uria lomvia) are emblematic of this conservation challenge, since they breed widely in the circumpolar Arctic, with many declining populations in the Atlantic. Threats faci

Arthroscopically assisted anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft without wound drainage : Short- to middle-term outcome

Introduction: Several studies have suggested that anterior cruciate ligament reconstruction (ACLR) without wound drainage has no impact on long-term follow-up. Aim: To investigate a prospective patient series as measured by the patient-administered disease-specifc questionnaire Knee injury and Osteoarthritis Outcome Score (KOOS). Material and methods: The study included 101 consecutive patients (7

Observations on normal EEG activity in different brain regions of the unrestrained swine

This methodological and electrophysiological study was undertaken with the aim of obtaining possibilities for evaluating objectively the ethical value of using high concentration CO2 inhalation as pre-slaughter anaesthesia for swine. A technique for implantation of recording electrodes into the porcine neocortex and limbic system is described, as are results of EEG recording from these brain regio

Thresholds and noise limitations of colour vision in dim light

Colour discrimination is based on opponent photoreceptor interactions, and limited by receptor noise. In dim light, photon shot noise impairs colour vision, and in vertebrates, the absolute threshold of colour vision is set by dark noise in cones. Nocturnal insects (e.g. moths and nocturnal bees) and vertebrates lacking rods (geckos) have adaptations to reduce receptor noise and use chromatic visi

The remarkable visual capacities of nocturnal insects : Vision at the limits with small eyes and tiny brains

Nocturnal insects have evolved remarkable visual capacities, despite small eyes and tiny brains. They can see colour, control flight and land, react to faint movements in their environment, navigate using dim celestial cues and find their way home after a long and tortuous foraging trip using learned visual landmarks. These impressive visual abilities occur at light levels when only a trickle of p

Stellar performance : Mechanisms underlying milky way orientation in dung beetles

Nocturnal dung beetles (Scarabaeus satyrus) are currently the only animals that have been demonstrated to use the Milky Way for reliable orientation. In this study, we tested the capacity of S. satyrus to orient under a range of artificial celestial cues, and compared the properties of these cues with images of the Milky Way simulated for a beetle’s visual system. We find that the mechanism that p

Comparative system identification of flower tracking performance in three hawkmoth species reveals adaptations for dim light vision

Flight control in insects is heavily dependent on vision. Thus, in dim light, the decreased reliability of visual signal detection also prompts consequences for insect flight. We have an emerging understanding of the neural mechanisms that different species employ to adapt the visual system to low light. However, much less explored are comparative analyses of how low light affects the flight behav

Insect photoreceptor adaptations to night vision

Night vision is ultimately about extracting information from a noisy visual input. Several species of nocturnal insects exhibit complex visually guided behaviour in conditions where most animals are practically blind. The compound eyes of nocturnal insects produce strong responses to single photons and process them into meaningful neural signals, which are amplified by specialized neuroanatomical

The dual rod system of amphibians supports colour discrimination at the absolute visual threshold

The presence of two spectrally different kinds of rod photoreceptors in amphibians has been hypothesized to enable purely rod-based colour vision at very low light levels. The hypothesis has never been properly tested, so we performed three behavioural experiments at different light intensities with toads (Bufo) and frogs (Rana) to determine the thresholds for colour discrimination. The thresholds

Labor market consequences of growing up with a sibling with type 1-diabetes

Economic research on child health and future labor market outcomes has mainly focused on children with impaired health themselves, and only recently begun to assess spillover effects for siblings. Yet, the challenge to accommodate a family's routines within the requirements of a complex and time-consuming disease is most likely to spillover on siblings. While the burden of ill health and managing

Migration and integration on the Baltic island of Öland in the Iron Age

This study explores a bi-isotopic approach to migration, adding δ18O values to samples with 87Sr/86Sr values for 109 individuals from the Iron Age (500 BCE–1050 CE) on the island of Öland, Sweden. Determining a local baseline for 87Sr/86Sr was complicated due to the wide range of variation in faunal samples so we divided the human values into three groups: local, non-local and undetermined. The ad

Unveiling the excited state energy transfer pathways in peridinin-chlorophyll a-protein by ultrafast multi-pulse transient absorption spectroscopy

Time-resolved multi-pulse methods were applied to investigate the excited state dynamics, the interstate couplings, and the excited state energy transfer pathways between the light-harvesting pigments in peridinin-chlorophyll a-protein (PCP). The utilized pump-dump-probe techniques are based on perturbation of the regular PCP energy transfer pathway. The PCP complexes were initially excited with a

Capillary stability of vapor-liquid-solid crystallization processes and their comparison to Czochralski and Stepanov growth methods

Epitaxial semiconductor nanowires grown with vapor-liquid-solid crystallization processes are very attractive nanoscale objects for many different applications. Despite extensive studies of the growth mechanism, there is still a lack of understanding of the growth process; in particular, the stability of the vapor-liquid-solid crystallization process has not previously been studied. Here we examin

Origins of inhabitants from the 16th century Sala (Sweden) silver mine cemetery – A lead isotope perspective

Historical documents record the operation of a silver mine from the 16th century AD located near the former village of Salberget in central Sweden. The historical record describes several categories of inhabitants, including local families, workers and miners, foreign engineers and mining specialists, as well as war captives and criminals used as forced labor in the mines. A church yard in the vic

Global isoprene and monoterpene emissions under changing climate, vegetation, CO2 and land use

Plants emit large quantities of isoprene and monoterpenes, the main components of global biogenic volatile organic compound (BVOC) emissions. BVOCs have an important impact on the atmospheric composition of methane, and of short-lived radiative forcing agents (e.g. ozone, aerosols etc.). It is therefore necessary to know how isoprene and monoterpene emissions have changed over the past and how fut

An introduction to the special issue : Ontological securities in world politics

The research community of ontological security scholars is vibrant and wide-ranging, defined by a conceptual core and by the themes through which scholars register their disagreements. In this special issue we have collected some of the work that has been produced or inspired by discussions and meetings during the last few years. The goal is to showcase some of the breadth of insights and possibil

Wurtzite (Ga,Mn)As nanowire shells with ferromagnetic properties

(Ga,Mn)As having a wurtzite crystal structure was coherently grown by molecular beam epitaxy on the {1100} side facets of wurtzite (Ga,In)As nanowires and further encapsulated by (Ga,Al)As and low temperature GaAs. For the first time, a truly long-range ferromagnetic magnetic order is observed in non-planar (Ga,Mn)As, which is attributed to a more effective hole confinement in the shell containing