40,447 research outputs found
Measuring the Expansion of the Universe Through Changes in the CMB Photosphere
The expansion of the universe may be observed in ``realtime'' by measuring
changes in the patterns of the anisotropy in the CMB. As the universe ages, the
surface of decoupling--or the CMB photosphere--moves away from us and samples a
different gravitational landscape. The response of the CMB to this new
landscape results in a different pattern than we observe today. The largest
change occurs at l~900. We show that with an array of detectors that we may
envision having in a couple of decades, one can in principle measure the change
in the anisotropy with two high precision measurements separated by a century.Comment: 4 pages, 8 figures, submitted to Ap
Development of a real-time full-field range imaging system
This article describes the development of a full-field range imaging system employing a high frequency amplitude modulated light source and image sensor. Depth images are produced at video frame rates in which each pixel in the image represents distance from the sensor to objects in the scene.
The various hardware subsystems are described as are the details about the firmware and software implementation for processing the images in real-time. The system is flexible in that precision can be traded off for decreased acquisition time. Results are reported to illustrate this versatility for both high-speed (reduced precision) and high-precision operating modes
Special Issue "The Exposome in Immune Evolution, Health and Disease"
The exposome can be defined as the measure of all exposures of an individual in a lifetime, and how these relate to health. Therefore, the topic of immune health and development, from an exposome perspective, is a focus of increasing interest.
This Special Issue aims to collect state-of-the-art primary research studies and review articles from international experts and leading groups on roles of the exposome in immune evolution and disease mechanisms.
Prof. Sigrun Lange
Guest Edito
Extracellular Vesicles in Phylogeny
Extracellular vesicles (EVs) are cell-derived lipid vesicles in a size range of 20â1000 nm; often, these are classified as smaller and larger EVs in the literature or also commonly called small EVs (âexosomesâ) and medium/large EVs (âmicrovesiclesâ) [...
Surface anchoring on layers of grafted liquid-crystalline chain molecules: A computer simulation
By Monte Carlo simulations of a soft ellipsoid model for liquid crystals, we
study whether a layer of grafted liquid-crystalline chain molecules can induce
tilt in a nematic fluid. The chains are fairly short (four monomers) and made
of the same particles as the solvent. They are attached to a substrate which
favors parallel (planar) alignment. At low grafting densities, the substrate
dominates and we observe planar alignment. On increasing the grafting density,
we find a first order transition from planar to tilted alignment. Beyond the
transition, the tilt angle with respect to the surface normal decreases
continuously. The range of accessible anchoring angles is quite large.Comment: To appear in J. Chem. Phy
A family of Prym-Tyurin varieties of exponent 3
We investigate a family of correspondences associated to \'etale coverings of
degree 3 of hyperelliptic curves. They lead to Prym-Tyurin varieties of
exponent 3. We identify these varieties and derive some consequences.Comment: names of authors correcte
Electrochemical detection of the toxic dinoflagellate Alexandrium ostenfeldii with a DNA-biosensor
The steady rise of observations of harmful or toxic algal blooms throughout the world in the past decades constitute a menace for coastal ecosystems and human interests. As a consequence, a number of programs have been launched to monitor the occurrence of harmful and toxic algae. However, the identification is currently done by microscopic examination, which requires a broad taxonomic knowledge, expensive equipment and is very time consuming. In order to facilitate the identification of toxic algae, an inexpensive and easy-to-handle DNA-biosensor has been adapted for the electrochemical detection of the toxic dinoflagellate Alexandrium ostenfeldii. The detection of the toxic algae is based on a sandwich hybridisation, which is carried out on a disposable sensor chip. A set of two probes for the species specific identification of A. ostenfeldii was developed. The specificity of the probes could be shown in dot-blot hybridisation and with the DNA-biosensor. The sensitivity of the DNA-biosensor was optimised with respect to hybridisation temperature and NaCl-concentration and a significant increase of the sensitivity of the DNA-biosensor could be obtained by a fragmentation of the rRNA prior to the hybridisation and by adding a helper oligonucleotide, which binds in close proximity to the probes to the hybridisation
Stray light in the Infrared Astronomical Satellite (IRAS)
Changes made to the telescope and critical objects considered in modeling these changes into the APART program are described. The optical system was analyzed for scattered light, diffracted then scattered radiation, and thermally emitted radiation. The damaged area of the primary to mirror was also examined. Results are presented in tables and graphs
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