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Peatland dynamics in response to past and potential future climate change : A regional modelling approach

En majoritet av de nordliga torvmarkerna utvecklades under holocen som ett resultat av en positiv massbalans mellan nettoprimärproduktion och heterotrofa nedbrytningshastigheter. Sedan dess har de lagrat stora mängder kol i terrestra ekosystem. En betydande del av dessa områden sammanfaller också med regioner med underliggande permafrost och uppvisar olika ackumulationsmönster av torv. Således, föThe majority of the northern peatlands developed during the Holocene as a result of a positive mass balance between net primary productivity (NPP) and heterotrophic decomposition rates. Over that time they have sequestered a huge amount of carbon in terrestrial ecosystems. A significant proportion of these areas also coincides with areas underlain with permafrost and shows a diverse range of peat

Implications of cerebrovascular ATP-binding cassette transporter G1 (ABCG1) and apolipoprotein M in cholesterol transport at the blood-brain barrier

Impaired cholesterol/lipoprotein metabolism is linked to neurodegenerative diseases such as Alzheimer's disease (AD). Cerebral cholesterol homeostasis is maintained by the highly efficient blood-brain barrier (BBB) and flux of the oxysterols 24(S)-hydroxycholesterol and 27-hydroxycholesterol, potent liver-X-receptor (LXR) activators. HDL and their apolipoproteins are crucial for cerebral lipid tra

Core level photoelectron spectroscopy probed heterogeneous xenon/neon clusters

Binary rare gas clusters; xenon and neon which have a significant contrariety between sizes, produced by a co-expansion set up and have been studied using synchrotron radiation based x-ray photoelectron spectroscopy. Concentration ratios of the heterogeneous clusters; 1%, 3%, 5% and 10% were controlled. The core level spectra were used to determine structure of the mixed cluster and analyzed by co

Precambrian gold mineralization at Djamgyr in the Kyrgyz Tien Shan : Tectonic and metallogenic implications

The Djamgyr gold deposit is located within the Neoproterozoic basement of the Middle Tien Shan terrane immediately west of the Talas-Fergana fault. The deposit comprises a system of auriferous quartz veins cross-cutting the Beshtor plagiogranite. The veins are surrounded by hydrothermal alteration aureoles and are oriented parallel to the Talas-Fergana fault. The Beshtor granite sampled in the vic

Ductilization of aluminium alloy 6056 by friction stir processing

The ductility of Al alloys is dictated by the nucleation, growth and coalescence of small internal voids originating from intermetallic particle fracture and from the presence of pre-existing porosity. The ductility is degraded when intermetallic particles are large and clustered. A low ductility adversely impacts both forming operations and the integrity of structural components. Local stirring u

The origin of species richness patterns along environmental gradients : uniting explanations based on time, diversification rate and carrying capacity

Aims: Patterns of species richness, such as the remarkable biodiversity of tropical regions, have been documented and studied for centuries. However, their underlying evolutionary and ecological causes are still incompletely understood. A commonly stated paradigm in the literature is that high richness in some habitats is directly caused by one of three competing explanations: (1) greater time-for

The spatial variation of O3,NO,NO2and NOx and the relation between them in two Swedish cities

Ozone and nitrogen oxides (NOx) are air pollutants with known associations to adverse health effects on humans. Few studies have simultaneously measured ozone and nitrogen oxides with high spatial resolution. The main aim of this paper was to assess the levels and variation of ground-level ozone, NO2 and NOx in two Swedish cities. An additional aim was to describe the levels of these pollutants wi

Dietary 2-oxoglutarate prevents bone loss caused by neonatal treatment with maximal dexamethasone dose

Synthetic glucocorticoids (GCs) are widely used in the variety of dosages for treatment of premature infants with chronic lung disease, respiratory distress syndrome, allergies, asthma, and other inflammatory and autoimmune conditions. Yet, adverse effects such as glucocorticoid-induced osteoporosis and growth retardation are recognized. Conversely, 2-oxoglutarate (2-Ox), a precursor of glutamine,

Size and property bimodality in magnetic nanoparticle dispersions : single domain particles vs. strongly coupled nanoclusters

The widespread use of magnetic nanoparticles in the biotechnical sector puts new demands on fast and quantitative characterization techniques for nanoparticle dispersions. In this work, we report the use of asymmetric flow field-flow fractionation (AF4) and ferromagnetic resonance (FMR) to study the properties of a commercial magnetic nanoparticle dispersion. We demonstrate the effectiveness of bo

Direct nucleation, morphology and compositional tuning of InAs1-xSb x nanowires on InAs (111) B substrates

III-V ternary nanowires are interesting due to the possibility of modulating their physical and material properties by tuning their material composition. Amongst them InAs1-xSb x nanowires are good candidates for applications such as Infrared detectors. However, this material has not been grown directly from substrates, in a large range of material compositions. Since the properties of ternaries a

Formation of reverse vesicles in silicone surfactant systems

This study deals with the formation of reverse vesicles based on the phase behavior of silicone surfactants. The surfactants, polyoxyethylene–polydimethylsiloxane and polyoxyethylene–polyoxypropylene–polydimethylsiloxane copolymer, were found to form lamellar liquid crystal phases in three different types of silicone oil upon the addition of a certain amount of water. A conventional method in whic

Actogram analysis of free-flying migratory birds : new perspectives based on acceleration logging

The use of accelerometers has become an important part of biologging techniques for large-sized birds with accelerometer data providing information about flight mode, wing-beat pattern, behaviour and energy expenditure. Such data show that birds using much energy-saving soaring/gliding flight like frigatebirds and swifts can stay airborne without landing for several months. Successful acceleromete

The devil lies in the definition : competing approaches to fossil fuel subsidies at the IMF and the OECD

Fossil fuel subsidy reform has in recent years been addressed by international economic organizations including the International Monetary Fund (IMF) and the Organisation for Economic Co-operation and Development (OECD). The two organizations have differed significantly in how they define fossil fuel subsidies. The IMF’s definition constitutes a radical break with previous definitions by including

Local culture as a context for entrepreneurial activities

This paper examines how an industrial legacy leads to the formation of a distinct local culture and how the culture’s survival provides a context for the subsequent entrepreneurial activities in new local industries. The discussion about culture as a key driver of entrepreneurship and economic growth is well established in the academic debate. However, we know little about how culture is formed. T

Elevated miR-130a/miR130b/miR-152 expression reduces intracellular ATP levels in the pancreatic beta cell

MicroRNAs have emerged as important players of gene regulation with significant impact in diverse disease processes. In type-2 diabetes, in which impaired insulin secretion is a major factor in disease progression, dysregulated microRNA expression in the insulin-secreting pancreatic beta cell has been widely-implicated. Here, we show that miR-130a-3p, miR-130b-3p, and miR-152-3p levels are elevate

On the formation of inclusion complexes at the solid/liquid interface of anchored temperature-responsive PNIPAAM diblock copolymers with γ-cyclodextrin

The thermal responsive behavior of adsorbed layers of diblock copolymers of poly(N-isopropylacrylamide) (PNIPAAM) and poly((3-acrylamidopropyl)trimethylammonium chloride) (PAMPTMA(+)) with γ-cyclodextrin (γ-CD) at the solid/liquid interface has been investigated using three in situ techniques: null ellipsometry, quartz–crystal microbalance with dissipation monitoring, and neutron reflectometry. Th