9,301 research outputs found
Surface Superconductivity in Presence of Corners
We consider an extreme type-II superconducting wire with non-smooth cross
section, i.e., with one or more corners at the boundary, in the framework of
the Ginzburg-Landau theory. We prove the existence of an interval of values of
the applied field, where superconductivity is spread uniformly along the
boundary of the sample. More precisely the energy is not affected to leading
order by the presence of corners and the modulus of the Ginzburg-Landau
minimizer is approximately constant along the transversal direction. The
critical fields delimiting this surface superconductivity regime coincide with
the ones in absence of boundary singularities.Comment: 20 pages, pdfLaTex, 2 figure
Nuclear Track Detectors for Environmental Studies and Radiation Monitoring
Several improvements were made for Nuclear Track Detectors (NTDs) used for
environmental studies and for particle searches. A new method was used to
determine the bulk etch rate of CR39 and Makrofol NTDs. It is based on the
simultaneous measurement of the diameter and of the height of etch-pit cones
caused by relativistic heavy ions (158 A GeV Pb(82+) and In(49+) ions) and
their fragments. The use of alcohol in the etching solution improves the
surface quality of NTDs and it raises their thresholds. The detectors were used
for the determination of nuclear fragmentation cross sections of Iron and
Silicon ions of 1.0 and 0.41 GeV/nucleon. These measurements are important for
the determination of doses in hadron therapy and for doses received by
astronauts. The detectors were also used in the search of massive particles in
the cosmic radiation, for the determination of the mass spectrum of cosmic rays
and for the evaluation of Po(210) alpha decay and of natural radon
concentrations.Comment: 7 pages, 5 EPS figures. Presented at the 10th Topical Seminar on
Innovative Particle and Radiation Detectors, 1-5 October 2006, Siena, Ital
Iatrogenic Cushing syndrome due to drug interaction between inhaled fluticasone and cobicistat
In this paper we report a case of iatrogenic Cushing syndrome due to a pharmacological interaction between fluticasone and cobicistat. Inhaled corticosteroids were previously thought to be safe, but increasing numbers of cases of iatrogenic Cushing syndrome are being reported, especially in patients taking cytochrome P450 inhibitors, including cobicistat. Although the drug interaction between cobicistat and fluticasone has been described elsewhere, to our knowledge we present one of the first descriptions of iatrogenic Cushing syndrome due to this pharmacological interaction
Meaurement of Cosmic Ray elemental composition from the CAKE balloon experiment
CAKE (Cosmic Abundances below Knee Energies) was a prototype balloon
experiment for the determination of the charge spectra and of abundances of the
primary cosmic-rays (CR) with Z10. It was a passive instrument made of
layers of CR39 and Lexan nuclear track detectors; it had a geometric acceptance
of 0.7 msr for Fe nuclei. Here, the scanning and analysis strategies,
the algorithms used for the off-line filtering and for the tracking in
automated mode of the primary cosmic rays are presented, together with the
resulting CR charge distribution and their abundances.Comment: 5 pages, 8 figure
Search for nuclearites with the SLIM detector
We discuss the properties of cosmic ray nuclearites, from the point of view
of their search with large nuclear track detector arrays exposed at different
altitudes, in particular with the SLIM experiment at the Chacaltaya high
altitude lab (5290 m a.s.l.). We present calculations concerning their
propagation in the Earth atmosphere and discuss their possible detection with
CR39 and Makrofol nuclear track detectors.Comment: 11 pages, 6 figure
Bulk Etch Rate Measurements and Calibrations of Plastic Nuclear Track Detectors
New calibrations of CR39 and Makrofol nuclear track detectors have been
obtained using 158 A GeV Pb (82+) and In (49+) ions; a new method for the bulk
etch rate determination, using both cone height and base diameter measurements
was developed. The CR39 charge resolution based on the etch-pit base area
measurement is adequate to identify nuclear fragments in the interval 7 <=
Z/beta <= 49. For CR39 the detection threshold is at REL~50 MeV cm^2/g,
corresponding to a nuclear fragment with Z/beta~7. Base cone area distributions
for Makrofol foils exposed to Pb (82+) ions have shown for the first time all
peaks due to nuclear fragments with Z > 50; the distribution of the etched cone
heights shows well separated individual peaks for Z/beta = 78 - 83 (charge
pickup). The Makrofol detection threshold is at REL 2700 MeV cm^2/g,
corresponding to a nuclear fragment with Z/beta~50.Comment: 11 pages, 5 EPS figures. Submitted to Nucl. Instr. Meth.
Building blocks of the human heart
Cardiomyocytes derived from human pluripotent stem cells
(hPSC-CMs) are arguably the best in vitro system for studying human cardiac
developmental processes and mechanisms underlying cardiac diseases. However,
hPSC-CMs are functionally immature compared to CMs in the adult heart.
Additionally, the heart is organized as a complex three-dimensional (3D)
organ composed of multiple cell types that are not isolated from one another
but instead constantly communicate with each other to ensure proper cardiac
function. By considering the heart as a collection of individual
building-blocks, protocols were developed in this thesis to differentiate all
of these multiple cardiac cell types from common hPSC-cardiac mesoderm
progenitors and subsequently mixing them in different combinations to
generate miniaturized 3D models of the heart that we termed “cardiac
microtissues”.
The research described in this thesis as well as its publications was supported by the following grants: European Research Council (ERCAdG 323182 STEMCARDIOVASC) and Transnational Research Project on Cardiovascular Diseases (JTC2016_FP-40-021 ACM-HF).
Financial support by the Dutch Heart Foundation for the publication of this thesis is gratefully acknowledged.LUMC / Geneeskund
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