1,746 research outputs found
Stable Magnetostatic Solitons in Yttrium Iron Garnet Film Waveguides for Tilted in-Plane Magnetic Fields
The possibility of nonlinear pulses generation in Yttrium Iron Garnet thin
films for arbitrary direction between waveguide and applied static in-plane
magnetic field is considered. Up to now only the cases of in-plane magnetic
fields either perpendicular or parallel to waveguide direction have been
studied both experimentally and theoretically. In the present paper it is shown
that also for other angles (besides 0 or 90 degrees) between a waveguide and
static in-plane magnetic field the stable bright or dark (depending on
magnitude of magnetic field) solitons could be created.Comment: Phys. Rev. B (accepted, April 1, 2002
Super-resolving multi-photon interferences with independent light sources
We propose to use multi-photon interferences from statistically independent
light sources in combination with linear optical detection techniques to
enhance the resolution in imaging. Experimental results with up to five
independent thermal light sources confirm this approach to improve the spatial
resolution. Since no involved quantum state preparation or detection is
required the experiment can be considered an extension of the Hanbury Brown and
Twiss experiment for spatial intensity correlations of order N>2
Depressed and excluded: Do depressive symptoms moderate recovery from ostracism?
Background. Prior studies show that depressed individuals react with more immediate reflexive need threat to ostracism than healthy controls. However, it remains unclear whether the observed difference between depressed individuals and healthy controls is caused by ostracism. To find out, the exclusion condition needs to be compared to a baseline condition: inclusion. Methods. We assessed depressive symptoms in N = 426 participants in an experimental study. Participants were included or excluded in Cyberball and indicated both their immediate reflexive need satisfaction level and their reflective need satisfaction level several minutes later to assess recovery. Results. Being excluded decreased reflexive need satisfaction levels for all participants. At the same time, the strength of depressive symptoms negatively predicted reflexive and reflective need satisfaction and was associated with slower recovery. Importantly, no moderation was observed: individuals with more depressive symptoms reported reduced need satisfaction levels regardless of being included or excluded in Cyberball. Limitations. The present findings were obtained with one paradigm only, albeit the most commonly used one: Cyberball. Depressive symptoms were assessed as self-report; future studies may wish to replicate the effects using structured clinical interviews. Conclusions. Depressive symptoms come with lowered need satisfaction levels, irrespective of whether individuals are socially excluded or included. Clinical practitioners should be aware of the relationship between chronic need threat and depression in order to help their patients overcome it
Progress in Developing Hybrid RPCs: GEM-like Detectors with Resistive Electrodes
We have recently developed an innovative detector of photons and charged
particles: a GEM-like gaseous amplification structure with resistive electrodes
instead of commonly used metallic ones. This novel detector combines the best
property of GEMs- the capability to operate in a cascaded mode and in poorly
quenched gases - and of RPC: the protection against sparks. In this paper will
shortly review our latest achievements in this direction, however the main
focus will be given on a new advanced design that allows to build large area
detectors manufactured by a screen printing technology. The proposed detector,
depending on the applications, can operate either in a GEM mode (electron
multiplications through holes only) or as a hybrid RPC with simultaneous
amplifications in the drift region and in the holes. The possible applications
of this new detector will be discussed
The development of experimental chamber and methodological approach for gas-phase hydrogen permeation study
In this work, the development of an experimental chamber and a technique for conducting experiments to study the permeation of hydrogen through metal membranes using an automated complex Gas Reaction Controller are realized. This complex makes it possible to carry out experiments to study the hydrogen permeation with the following parameters: hydrogen inlet pressure up to 50 atmospheres; the temperature in the chamber is from -30 °С to 1000 °С. The sample size is limited to 10 mm. The procedure for calculating the diffusion coefficient, based on the Fick equation, is presented in work. The study of the hydrogen permeation in a titanium alloy Ti-6Al-4V is presented in this research
Criteria for the differentiation between young and old Onchocerca volvulus filariae
Drugs exist that show long-lasting inhibition of embryogenesis and microfilaria production or macrofilaricidal activity against Onchocerca volvulus. Therefore, the patients have to be followed-up for several years. Clinical drug trials have to be performed in areas with ongoing transmission to assess the efficacy on younger worms. In addition, future vaccine trials may also require demonstrating efficacy against establishment of new worms. For the evaluation of the efficacy, it is necessary to differentiate between older worms, which were exposed to the drug, and younger worms newly acquired after drug treatment or vaccination. Here, we describe criteria for the differentiation between young and old filariae based on histological studies of worms with a known age from travellers, or from children, or patients living in areas with interrupted transmission in Burkina Faso, Ghana or Uganda. Older worms were larger and presented degenerated tissues. Gomori's iron stain showed that the worms accumulated more iron with increasing age, first in the gut and later in other organs. Using an antibody against O. volvulus lysosomal aspartic protease, the gut of young worms was stained only weakly; whereas, it was stronger labelled in older worms, accompanied by additional staining of hypodermis and epithelia. Using morphological and immunohistological criteria, it was possible to differentiate young (1–3 years old) from older females and to identify young males
Thermodynamics of quantum Brownian motion with internal degrees of freedom: the role of entanglement in the strong-coupling quantum regime
We study the influence of entanglement on the relation between the
statistical entropy of an open quantum system and the heat exchanged with a low
temperature environment. A model of quantum Brownian motion of the
Caldeira-Leggett type - for which a violation of the Clausius inequality has
been stated by Th.M. Nieuwenhuizen and A.E. Allahverdyan [Phys. Rev. E 66,
036102 (2002)] - is reexamined and the results of the cited work are put into
perspective. In order to address the problem from an information theoretical
viewpoint a model of two coupled Brownian oscillators is formulated that can
also be viewed as a continuum version of a two-qubit system. The influence of
an additional internal coupling parameter on heat and entropy changes is
described and the findings are compared to the case of a single Brownian
particle.Comment: 10 pages, 11 figure
Expressing Measurement Uncertainty in OCL/UML Datatypes
Uncertainty is an inherent property of any measure or estimation performed in any physical setting, and therefore it needs to
be considered when modeling systems that manage real data. Although several modeling languages permit the representation of measurement uncertainty for describing certain system attributes, these aspects are not normally incorporated into their type systems. Thus, operating with uncertain values and propagating uncertainty are normally cumbersome processes, di cult to achieve at the model level. This paper proposes an extension of OCL and UML datatypes to incorporate data uncertainty coming from physical measurements or user estimations into the models, along with the set of operations de ned for the values of these types.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Great Sumatra Earthquake Registers on Electrostatic Sensor
Strong electrical signals that correspond to
the Mw = 9.3 earthquake of 26 December 2004,
which occurred at 0058:50.7 UTC
off the west coast of northern Sumatra, Indonesia,
were recorded by an electrostatic sensor
(a device that detects short-term variations in
Earth’s electrostatic fi eld) at a seismic station
in Italy, which had been installed to study the
infl uence of local earthquakes on a new landslide
monitoring system.
Electrical signals arrived at the station practically
instantaneously and were detected up
to several hours before the onset of the Sumatra
earthquake (Figure 1) as well as before
local quakes. The corresponding seismic signals
(p-waves) arrived 740 seconds after the
start of the earthquake. Because the electrical
signals travel at the speed of light, electrical
monitoring for the global detection of very
strong earthquakes could be an important
tool in signifi cantly increasing the hazard
alert window
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