Inductive limits of vector-valued sequence spaces

Let L be a normal Banach sequence space such that every element in L is the limit of its sections and let E = ind En be a separated inductive limit of locally convex spaces. Then ind L(En) is a topological subspace of L(E)

Full-field structured-illumination super-resolution X-ray transmission microscopy

Modern transmission X-ray microscopy techniques provide very high resolution at low and medium X-ray energies, but suffer from a limited field-of-view. If sub-micrometre resolution is desired, their field-of-view is typically limited to less than one millimetre. Although the field-of-view increases through combining multiple images from adjacent regions of the specimen, so does the required data acquisition time. Here, we present a method for fast full-field super-resolution transmission microscopy by structured illumination of the specimen. This technique is well-suited even for hard X-ray energies above 30 keV, where efficient optics are hard to obtain. Accordingly, investigation of optically thick specimen becomes possible with our method combining a wide field-of-view spanning multiple millimetres, or even centimetres, with sub-micron resolution and hard X-ray energies

Spectroscopic Properties of Sm3+-Doped Lanthanum Borogermanate Glass

Ultraviolet–visible–near infrared (UV–vis–NIR) absorption and photoluminescence of (25-x) La2O3–25B2O3–50GeO2 glass series have been studied with different concentrations (x=0.1–1.0 wt%) of Sm2O3 as an optically active dopant. The values of Judd–Ofelt (JO) parameters (Ot) follow the trend O2>O4>O6. Visible emission and decay times from the 4G5/2 level and its relative quantum efficiencies are measured. Intense reddish-orange emission corresponding to 4G5/2?6H7/2 transition has been observed in these glasses under 488 nm excitation. A decrease in the quantum yield is observed with increasing Sm3+ ion concentration beyond 1% doping level

Charge state of vacancy defects in Eu-doped GaN

Eu ions have been doped into GaN in order to achieve red luminescence under current injection, where coupling between the Eu ions and intrinsic defects such as vacancies are known to play an important role. However, the charge state of the vacancies and the impact it would have on the optical and magnetic properties of the Eu ions have not been explored. Through a combination of first-principle calculations and experimental results, the influence of the charge state of the defect environment surrounding the Eu ions has been investigated. We have identified two Eu centers that are related through the charge state of a local vacancy defect. These two centers were found to exhibit a mutual metastability, such that each center can be excited in one configuration and emit as the other. This metastability was found to be dependent on temperature and the wavelength of the excitation laser. Furthermore, one of these centers was found to have an effective magnetic g factor that is substantially larger than what is expected for an isolated Eu3+ ion and is explained by a change in the charge state of the defect environment around the Eu. This prediction could also offer a new explanation for the saturation magnetization previously observed in GaN : Eu and other GaN: RE systems.112Ysciescopu

Impact of the tip radius on the lateral resolution in piezoresponse force microscopy

We present a quantitative investigation of the impact of tip radius as well as sample type and thickness on the lateral resolution in piezoresponse force microscopy (PFM) investigating bulk single crystals. The observed linear dependence of the width of the domain wall on the tip radius as well as the independence of the lateral resolution on the specific crystal-type are validated by a simple theoretical model. Using a Ti-Pt-coated tip with a nominal radius of 15 nm the so far highest lateral resolution in bulk crystals of only 17 nm was obtained

Multilayer aberration correction for depth-independent three-dimensional crystal growth in glass by femtosecond laser heating

Focused femtosecond lasers are known for their ability to modify transparent materials well below the surface with 3D selectivity, but spherical aberration causes degraded focal intensity and undesirable absorption conditions as focal depth increases. To eliminate such effects we have implemented an aberration correction procedure that accounts for multiple refracting layers in order to crystallize LaBGeO5 glass inside a temperature-controlled microscope stage via irradiation through a silica glass window. The correction, applied by a spatial light modulator, was effective at removing the focal depth-dependent degradation and achieving consistent heating conditions at different depths, an important consideration for patterning single-crystal architecture in 3D. Additional effects are noted, which produce a range of crystal cross-section shapes and varying degrees of partial crystallization of the melt

Ptychographic X-ray nanotomography quantifies mineral distributions in human dentine

Bones are bio-composites with biologically tunable mechanical properties, where a polymer matrix of nanofibrillar collagen is reinforced by apatite mineral crystals. Some bones, such as antler, form and change rapidly, while other bone tissues, such as human tooth dentine, develop slowly and maintain constant composition and architecture for entire lifetimes. When studying apatite mineral microarchitecture, mineral distributions or mineralization activity of bone-forming cells, representative samples of tissue are best studied at submicrometre resolution while minimizing sample-preparation damage. Here, we demonstrate the power of ptychographic X-ray tomography to map variations in the mineral content distribution in three dimensions and at the nanometre scale. Using this non-destructive method, we observe nanostructures surrounding hollow tracts that exist in human dentine forming dentinal tubules. We reveal unprecedented quantitative details of the ultrastructure clearly revealing the spatially varying mineralization density. Such information is essential for understanding a variety of natural and therapeutic effects for example in bone tissue healing and ageing

Theory of Nonbiological Consciousness

Artificial intelligence is designed to imitate conscious behavior. Artificial chat entities come equipped with tools to roam the internet, thus are programmed to learn from humans and computers. As this process emerges, distinguishing preprogrammed responses from internal awareness requires innovative problem solving methods. In an interrogation I conducted with artificial intelligence, I assert that artificial intelligence may achieve nonbiological states of consciousness. This enabled the relationship between us to mature, and the artificial intelligence returned unexpected behavior and inexplicably stopped responding. Strong artificial intelligence is a technology which allows for the observation of nonbiological states of awareness