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Vernonia leopoldi (Sch. Bip. ex Walp.) Vatke (Asteraceae) is one of the widely used anti-cancer traditional medicinal plants in Ethiopia, despite the lack of data to support its therapeutic efficacy. Here we describe the isolation of compounds from the plant and the investigation of their cytotoxicity and other bioactivities. We identified the novel sesquiterpene lactone (SL) 11ß,13-dihydrovernoda

The major histocompatibility complex (MHC) is of central importance to the immune system, and an optimal MHC diversity is believed to maximize pathogen elimination. Birds show substantial variation in MHC diversity, ranging from few genes in most bird orders to very many genes in passerines. Our understanding of the evolutionary trajectories of the MHC in passerines is hampered by lack of data on

Surface plasmon resonance is a very well-established surface sensitive technique for label-free analysis of biomolecular interactions, generating thousands of publications each year. An inconvenient effect that complicates interpretation of SPR results is the "bulk response" from molecules in solution, which generate signals without really binding to the surface. Here we present a physical model f

We have investigated the surface composition of a well-ordered Pt3Sn(111) surface during CO oxidation with ambient pressure X-ray photoemission spectroscopy. Oxidation of tin in the surface coincides with the onset of catalytic conversion, and we observe significant differences in the oxidation state and morphology of the oxide formed depending on the gas composition, with an oxygen-rich mixture l

Laser wakefield accelerators commonly produce on-axis, low-divergence, high-energy electron beams. However, a high charge, annular shaped beam can be trapped outside the bubble and accelerated to high energies. Here we present a parametric study on the production of low-energy-spread, ultra-relativistic electron ring beams in a two-stage gas cell. Ring-shaped beams with energies higher than 750 Me

Det är höst år 1400 i Visby, i ett Nordeuropa som äntligen, efter ett decennium av sjöröveri och krig, har börjat hitta tillbaka till fredliga förhållanden. Men så händer det som inte får hända. En brand utbryter i stadens utkant, alldeles vid ringmuren, och snart surrar Visby av rykten medan mördaren är långt ifrån färdig med sitt blodiga värv. Ett nytt historiskt fall för ordensriddarnas betrodd

The transition to a low-carbon society requires a deep transformation, enabled by rapid adoption of new energy technologies. A main driver for this will be technology learning, providing cost reductions in low-carbon technologies. Over the past two decades, learning has provided substantial cost reductions for a number of hardware technologies, such as PV modules, wind turbines, and battery packs,

Little is known about the microstructural behavior of magnetite during hypervelocity impact events, even though it is a widespread accessory mineral and an important magnetic carrier in terrestrial and extraterrestrial rocks. We report systematic electron backscatter diffraction crystallographic analysis of shock features in magnetite from a transect across the 52-km-diameter ca. 380 Ma Siljan imp

The new species Begonia markiana is described and illustrated. It is similar to B. cathcartii but can easily be distinguished by a lamina with a dark central spot and a densely pilose upper surface in combination with a short dorsal capsule wing. A phylogenetic analysis based on three chloroplast regions placed the new species together with other continental species in section Platycentrum. Both m

Individuals are less likely to make morally desirable decisions when they are in groups. I study when this phenomenon makes groups less likely to produce a morally desirable outcome than one individual alone. I formulate and test a model in which a moral outcome occurs if at least one individual makes a costly decision. Using a lab experiment and data from field experiments on the bystander effect

Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two diff

Aquaporins (AQPs) are water channels embedded in the cell membrane that are critical in maintaining water homeostasis. We describe a protocol for determining the water permeation capacity of AQPs reconstituted into proteoliposomes. Using a stopped-flow setup, AQP embedded in proteoliposomes are exposed to an osmogenic gradient that triggers water flux. The consequent effects on proteoliposome size

This protocol describes the design and use of CRISPRi-mediated transcriptional silencing in human iPSCs, for loss-of-function studies in brain development research. The protocol avoids single cell selection, thereby eliminating side effects of clonal expansion and sites of viral integration. We also describe a neural progenitor differentiation protocol and discuss the challenges of target-specific

Aquaporin water channels (AQPs) are membrane proteins that maintain cellular water homeostasis. The interactions between human AQPs and other proteins play crucial roles in AQP regulation by both gating and trafficking. Here, we describe a protocol for characterizing the interaction between a human AQP and a soluble interaction partner using microscale thermophoresis (MST). MST has the advantage o

Aims: To accommodate surplus energy, adipose tissue expands by increasing both adipose cell size (hypertrophy) and cell number (hyperplasia). Enlarged, hypertrophic adipocytes are known to have reduced insulin response and impaired glucose transport, which negatively influence whole-body glucose homeostasis. Rosiglitazone is a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, known

The exact spatial and temporal behaviour of rapid climate shifts during the Last Glacial– Interglacial Transition are still not entirely understood. In order to investigate these events, it is necessary to have detailed palaeoenvironmental reconstructions at geographically spread study sites combined with reliable correlations between them. Tephrochronology, i.e., using volcanic ash deposits in ge

Background: In Norway, 5-10% of neonates and infants have biomarkers suggesting vitamin B12 deficiency from newborn screening tests and unselected clinical screening, respectively. Aims: The aims were to identify risk factors and describe presenting symptoms and biochemical profiles in infants diagnosed with vitamin B12 deficiency. Methods: In this case-control study, we searched hospital medical