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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,

Maternal cancer and congenital anomalies in children ± a Danish nationwide cohort study

Several studies on pregnancy-Associated cancers have suggested an association with congenital anomalies in offspring. Previous studies have included maternal cancers diagnosed up to 2 years after pregnancy; however, long latency periods of some cancers mean that cancers diagnosed many years postpartum might have been present during pregnancy in a preclinical state. This paper considers the associa

Tillitsbaserad styrning : Ett ramverk

Detta PM föreslår ett första ramverk för begreppet tillitsbaserad styrning. En teoretisk och en praktisk definition av tillitsbaserad styrning föreslås. Baserat på en klassisk modell från den internationella tillitsforskningen antas tilliten utgå från en bedömning av tillitsvärdigheten hos motparten, givet dennes förmåga (kunskap, m.m.), dennes integritet och dennes hjälpvillighet. Det slås vidare

Cytohesin 1 regulates homing and engraftment of human hematopoietic stem and progenitor cells

Adhesion is a key component of hematopoietic stem cell regulation mediating homing and retention to the niche in the bone marrow. Here, using an RNA interference screen, we identify cytohesin 1 (CYTH1) as a critical mediator of adhesive properties in primary human cord blood-derived hematopoietic stem and progenitor cells (HSPCs). Knockdown of CYTH1 disrupted adhesion of HSPCs to primary human mes

An 'alpha-beta' of pancreatic islet microribonucleotides

MicroRNAs (miRNAs) are cellular, short, non-coding ribonucleotides acting as endogenous posttranscriptional repressors following incorporation in the RNA-induced silencing complex. Despite being chemically and mechanistically very similar, miRNAs exert a multitude of different cellular effects by acting on mRNA species, whose gene-products partake in a wide array of processes.Here, the aim was to

Estimating prevalence of avian haemosporidians in natural populations : A comparative study on screening protocols

Background: Birds harbour an astonishing diversity of haemosporidian parasites. Renewed interest in avian haemosporidians as a model system has placed a greater emphasis on the development of screening protocols to estimate parasite prevalence and diversity. Prevalence estimates are often based on the molecular or blood-smear microscopy techniques. However, variation in diagnostic sensitivity amon

Precipitation drives global variation in natural selection

Climate change has the potential to affect the ecology and evolution of every species on Earth. Although the ecological consequences of climate change are increasingly well documented, the effects of climate on the key evolutionary process driving adaptation - natural selection - are largely unknown. We report that aspects of precipitation and potential evapotranspiration, along with the North Atl

Coevolution with bacteria drives the evolution of aerobic fermentation in Lachancea kluyveri

The Crabtree positive yeasts, such as Saccharomyces cerevisiae, prefer fermentation to respiration, even under fully aerobic conditions. The selective pressures that drove the evolution of this trait remain controversial because of the low ATP yield of fermentation compared to respiration. Here we propagate experimental populations of the weak-Crabtree yeast Lachancea kluyveri, in competitive co-c

Bioaccumulation and trophodynamics of the antidepressants sertraline and fluoxetine in laboratory-constructed, 3-level aquatic food chains

Although reports of pharmaceutical bioconcentration in aquatic organisms are increasing, less is known about trophic transfer in aquatic food webs. The bioaccumulation and trophodynamics of sertraline and fluoxetine, 2 selective serotonin reuptake inhibitors (SSRIs) frequently detected in aquatic environments, were tested by exposing constructed aquatic food chains to SSRIs under controlled labora