Paul Scherrer Institute

About: Paul Scherrer Institute is a facility organization based out in Villigen, Switzerland. It is known for research contribution in the topics: Neutron & Large Hadron Collider. The organization has 9248 authors who have published 23984 publications receiving 890129 citations. The organization is also known as: PSI.

Cerebral blood flow, blood volume and oxygen utilization. Normal values and effect of age.

Abstract: Regional cerebral blood flow (CBF), oxygen extraction ratio (OER), oxygen utilization (CMRO2) and blood volume (CBV) were measured in a group of 34 healthy volunteers (age range 22–82 yrs) using the 15O steady-state inhalation method and positron emission tomography. Between subjects CBF correlated positively with CMRO2, although the interindividual variability of the measured values was large. OER was not dependent on CMRO2, but highly negatively correlated with CBF. CBV correlated positively with CBF. When considering the values of all the regions of interest within a single subject, a strict coupling between CMRO2 and CBF, and between CBF and CBV was found, while OER was constant and independent of CBF and CMRO2. In ‘pure’ grey and white matter regions CMRO2, CBF and CBV decreased with age approximately 0.50% per year. In other regions the decline was less evident, most likely due to partial volume effects. OER did not change or showed a slight increase with age (maximum in the grey matter region 0.35%/yr). The results suggest diminished neuronal firing or decreased dendritic synaptic density with age.

Lasing in direct-bandgap GeSn alloy grown on Si

Abstract: Lasing is experimentally demonstrated in a direct bandgap GeSn alloy, grown directly onto Si(001). The authors observe a clear lasing threshold as well as linewidth narrowing at low temperatures.

Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmions at room temperature.

Abstract: Facing the ever-growing demand for data storage will most probably require a new paradigm. Nanoscale magnetic skyrmions are anticipated to solve this issue as they are arguably the smallest spin textures in magnetic thin films in nature. We designed cobalt-based multilayered thin films in which the cobalt layer is sandwiched between two heavy metals and so provides additive interfacial Dzyaloshinskii-Moriya interactions (DMIs), which reach a value close to 2 mJ m(-2) in the case of the Ir|Co|Pt asymmetric multilayers. Using a magnetization-sensitive scanning X-ray transmission microscopy technique, we imaged small magnetic domains at very low fields in these multilayers. The study of their behaviour in a perpendicular magnetic field allows us to conclude that they are actually magnetic skyrmions stabilized by the large DMI. This discovery of stable sub-100 nm individual skyrmions at room temperature in a technologically relevant material opens the way for device applications in the near future.

Tracking the ends: a dynamic protein network controls the fate of microtubule tips

Abstract: Microtubule plus-end tracking proteins (+TIPs) are a diverse group of evolutionarily conserved cellular factors that accumulate at the ends of growing microtubules. They form dynamic networks through the interaction of a limited set of protein modules, repeat sequences and linear motifs that bind to each other with moderate affinities. +TIPs regulate different aspects of cell architecture by controlling microtubule dynamics, microtubule interactions with cellular structures and signalling factors, and the forces that are exerted on microtubule networks.