Search results for "SCOPE"
showing 10 items of 2420 documents
Synthesis, electron microscopy and X-ray characterization of oxymagnesite, MgO·2MgCO3, formed from amorphous magnesium carbonate
2014
At present, the peculiar compound called oxymagnesite, MgO·2MgCO3, an intermediate formed during thermal decomposition of hydrated magnesium carbonates, has only been described a handful of times without a distinct description of its formation or morphology. In the current work we present the first scanning and transmission electron microscopy images of an oxymagnesite crystal together with its crystallographic data. Oxymagnesite was synthesized in a controlled manner via decomposition of amorphous magnesium carbonates (AMCs) subjected to varying relative humidity. We show that oxymagnesite is formed only when AMC is hydrated above a certain level, which we attribute to structural inequival…
Ultrastructural causes of rupture of hand tendons in patients with rheumatoid arthritis. A transmission and scanning electron microscopic study.
1993
To identify the cause of rupture of hand tendons in patients with rheumatoid arthritis, we studied the underlying ultrastructural changes of the collagenous fibril systems. Samples of the flexor digitorum superficialis (n = 12) and the extensor digitorum communis (n = 20) were taken during tenosynovectomy. Tendons dissected at necropsy (n = 30) served as controls. Specimens were analysed by transmission and scanning electron microscopy. Interfibrillar dysplastic fibrils, "Luse bodies", and intracellular collagen were found in rheumatoid tissues. The diameters of collagen fibrils were significantly reduced compared with the control group (p0.01). The duration of the disease usually correlate…
Use of accelerometers and gyros for hip and knee angle estimation
2013
In this paper a wearable sensor system, consisting of accelerometers and gyros, has been studied to estimate hip and knee angles. The proposed algorithm, developed in order to avoid the error accumulation due to gyroscopes drift, has been tested on angle measurement of the hip and knee of a commercial device for assisted gait. The results have shown a good accuracy of the angles estimation, also in high angle rate movement
Three-Dimensional Superconducting Nanohelices Grown by He
2019
Novel schemes based on the design of complex three-dimensional (3D) nanoscale architectures are required for the development of the next generation of advanced electronic components. He+ focused-ion-beam (FIB) microscopy in combination with a precursor gas allows one to fabricate 3D nanostructures with an extreme resolution and a considerably higher aspect ratio than FIB-based methods, such as Ga+ FIB-induced deposition, or other additive manufacturing technologies. In this work, we report the fabrication of 3D tungsten carbide nanohelices with on-demand geometries via controlling key deposition parameters. Our results show the smallest and highest-densely packed nanohelix ever fabricated s…
3D Printing Neuron Equivalent Circuits: An Undergraduate Laboratory Exercise.
2018
The electrical equivalent circuit for a neuron is composed of common electrical components in a configuration that replicates the passive electrical properties and behaviors of the neural membrane. It is a powerful tool used to derive such fundamental neurophysiological equations as the Hodgkin-Huxley equations, and it is also the basis for well-known exercises that help students to model the passive (Ohmic) properties of the neuronal membrane. Unfortunately, as these exercises require basic knowledge of electronics, they are generally not physically conducted in biomedical courses, but remain merely conceptual exercises in a book or simulations on a computer. In such manifestations, they l…
Numerical studies on neutrino oscillation physics in long baseline experiments
2018
This thesis examines the prospects of future long baseline neutrino oscillation experiments. Using computer simulation techniques, we calculate the experimental sensitivities for two experimental configurations in a set of important questions which are all relevant for modern day neutrino physics. First, we set focus on the determination of the θ23 octant, where the aim is to find whether the atmospheric neutrino mixing angle θ23 lies in the high octant, θ23 > 45◦, or in the low octant, θ23 < 45◦. On the other hand, we study how well the long baseline experiments could test the limits of the Standard Model by seeking deviations from the oscillation patterns that follow from the standard three…
Search for a diffuse flux of high-energy ¿µ with the ANTARES neutrino telescope
2011
A search for a diffuse flux of astrophysical muon neutrinos, using data collected by the ANTARES neutrino telescope is presented. A $(0.83\times 2\pi)$ sr sky was monitored for a total of 334 days of equivalent live time. The searched signal corresponds to an excess of events, produced by astrophysical sources, over the expected atmospheric neutrino background. The observed number of events is found compatible with the background expectation. Assuming an $E^{-2}$ flux spectrum, a 90% c.l. upper limit on the diffuse $\nu_\mu$ flux of $E^2\Phi_{90%} = 5.3 \times 10^{-8} \ \mathrm{GeV\ cm^{-2}\ s^{-1}\ sr^{-1}} $ in the energy range 20 TeV - 2.5 PeV is obtained. Other signal models with differ…
Search for Gravitational Waves Associated with Gamma-Ray Bursts Detected by Fermi and Swift during the LIGO-Virgo Run O3a
2022
Abbott, R., et al. (LIGO and VIRGO Collaboration)
Inference of proto-neutron star properties from gravitational-wave data in core-collapse supernovae
2021
The eventual detection of gravitational waves from core-collapse supernovae (CCSN) will help improve our current understanding of the explosion mechanism of massive stars. The stochastic nature of the late post-bounce gravitational wave signal due to the non-linear dynamics of the matter involved and the large number of degrees of freedom of the phenomenon make the source parameter inference problem very challenging. In this paper we take a step towards that goal and present a parameter estimation approach which is based on the gravitational waves associated with oscillations of proto-neutron stars (PNS). Numerical simulations of CCSN have shown that buoyancy-driven g-modes are responsible …
Modification of a commercial atomic force microscopy for low-noise, high-resolution frequency-modulation imaging in liquid environment.
2011
A key issue for high-resolution frequency-modulation atomic force microscopy imaging in liquids is minimizing the frequency noise, which requires a detailed analysis of the corresponding noise contributions. In this paper, we present a detailed description for modifying a commercial atomic force microscope (Bruker MultiMode V with Nanoscope V controller), aiming at atomic-resolution frequency-modulation imaging in ambient and in liquid environment. Care was taken to maintain the AFMs original stability and ease of operation. The new system builds upon an optimized light source, a new photodiode and an entirely new amplifier. Moreover, we introduce a home-built liquid cell and sample holder …