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Revisiting the coupling between NDVI trends and cropland changes in the Sahel drylands : A case study in western Niger

The impact of human activities via land use/cover changes on NDVI trends is critical for an improved understanding of satellite-observed changes in vegetation productivity in drylands. The dominance of positive NDVI trends in the Sahel, the so-called re-greening, is sometimes interpreted as a combined effect of an increase in rainfall and cropland expansion or agricultural intensification. Yet, th

Effect of coal mining on vegetation disturbance and associated carbon loss

Vegetation is an important part of the environment but may be subjected to disturbance in areas close to coal mines. This results in a slowing of the rate of biomass growth, which is caused by fading of vegetation. Simultaneously, carbon stored in vegetation is constantly released, weakening vegetation ability to act as a carbon sink. Indirect release of carbon during coal mining processes is diff

Neutron diffraction measurements on a reference metallic sample with a high-efficiency GEM side-on 10B-based thermal neutron detector

The upgraded version of the GEM side-on thermal neutron detector was successfully tested in a neutron diffraction experiment on a reference sample using the INES diffractometer at the ISIS spallation neutron source, UK. The performance of the new 10B4C-based detector is compared to that of a standard 3He tube, operating at the instrument as a part of the detectors assembly. The results show that t

Blood parasites shape extreme major histocompatibility complex diversity in a migratory passerine

Pathogens are one of the main forces driving the evolution and maintenance of the highly polymorphic genes of the vertebrate major histocompatibility complex (MHC). Although MHC proteins are crucial in pathogen recognition, it is still poorly understood how pathogen-mediated selection promotes and maintains MHC diversity, and especially so in host species with highly duplicated MHC genes. Sedge wa

Reduction of tree cover in West African woodlands and promotion in semi-arid farmlands

Woody vegetation in farmland acts as a carbon sink and provides ecosystem services for local people, but no macroscale assessments of the impact of management and climate on woody cover exist for drylands. Here we make use of very high spatial resolution satellite imagery to derive wall-to-wall woody cover patterns in tropical West African drylands. Our study reveals that mean woody cover in farml

Levels of retinal IAPP are altered in Alzheimer's disease patients and correlate with vascular changes and hippocampal IAPP levels

Islet amyloid polypeptide (IAPP) forms toxic aggregates in the brain of patients with Alzheimer's disease (AD). Whether IAPP also affects the retina in these patients is still unknown. Levels of IAPP in soluble and insoluble homogenate fractions of retina and hippocampus from AD patients and nondemented controls were analyzed using ELISA. Number of pericytes and vessel length were determined by an

Potato consumption and risk of pancreatic cancer in the HELGA cohort

Potatoes have been a staple food in many countries throughout the years. Potatoes have a high glycaemic index (GI) score, and high GI has been associated with several chronic diseases and cancers. Still, the research on potatoes and health is scarce and contradictive, and we identified no prospective studies that had investigated the association between potatoes as a single food and the risk of pa

A distributed solute model : An extended two-pore model with application to the glomerular sieving of ficoll

One of the many unresolved questions regarding the permeability of the glomerular filtration barrier is the reason behind the marked difference in permeability between albumin and polysaccharide probe molecules such as Ficoll and dextran of the same molecular size. Although the differences in permeability have been mainly attributed to charge effects, we have previously shown that this would requi

Cerebellar development and very preterm birth interactions with neonatal events

AbstractThe cerebellum is an important part of the brain and in very preterm infants the cerebellum is smaller at term equivalent age compared to that of infants born at term.Hypothesis and aims: The general hypothesis is that preterm birth per se causes cerebellar underdevelopment and that certain events following preterm birth, either complications or treatments, can aggravate the underdevelopme

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The genus Draba L. is a conspicuous element of the arctic flora, comprising about 350 species worldwide which mostly are arctic-alpine polyploids. Previously, it has mainly been Draba incana L., D. norvegica Gunn., D. nivalis Liljebl., D. alpina L., D. fladnizensis Wulf., D. daurica DC., D. lactea and D. cinerea Adams that have been considered as belonging to the Icelandic flora. In this paper we

Patterns of developmental plasticity in response to incubation temperature in reptiles

Early life environments shape phenotypic development in important ways that can lead to long-lasting effects on phenotype and fitness. In reptiles, one aspect of the early environment that impacts development is temperature (termed 'thermal developmental plasticity'). Indeed, the thermal environment during incubation is known to influence morphological, physiological, and behavioral traits, some o

Qualitative modelling of functional relationships in marine benthic communities

In order to better understand and predict the dynamics of benthic macroinvertebrate communities, we need to first define the functional components of benthic biodiversity and then provide a mechanistic description of how they interact with their abiotic environment, their basic resources and each other. These interactions should be largely controlled by readily available biological traits, making

Modeling the effects of abiotic and biotic factors on the depth distribution of Fucus vesiculosus in the Baltic Sea

The conspicuous retreat of the key species Fucus vesiculosus from the deeper parts of its former distribution area in the Baltic Sea has triggered extensive research on the factors that control its growth. Based on recently obtained knowledge on a large number of potential drivers, we developed a numerical model incorporating effects of abiotic factors on the physiological functions of photosynthe

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Dansk udtale kan give selv den mest ihærdige svensker grå hår i hovedet. Tre relativt simple konstruktioner som ordet er dit, der er røg i køkkenet, og de skal nå toget til Odense er givetvis lette at forstå i en sms eller mail, fordi de fleste af ordene er genkendelige, måske bortset fra nå (hinna). Men optræder de tre konstruktioner i en samtale, er de hverken lette at forstå eller lette at udta

Intra-annual variability of wood formation and delta C-13 in tree-rings at Hyytiala, Finland

Investigation of the relationship between tree-ring stable carbon isotope composition (δ13C) and environmental variables at the intra-seasonal scale can inform on the understanding of the environmental forcing affecting trees during the active period of radial growth. Recent progress in the measurement techniques for assessing the δ13C signature of tree rings at high spatial resolution provides an