1,721,131 research outputs found
Creativity and psychopathology: higher rates of psychosis proneness and nonright-handedness among creative artists compared to same age and gender peers
No full textCreative people have been found to score higher on psychopathologic scales in standardized tests, particularly on the scales that measure traits of psychoticism, and to be more likely to report an excess of nonright handedness compared with controls. However, results are inconsistent across surveys and methodologies, and the contribution of substance abuse has rarely been measured. In this study, 80 creative artists were compared with 80 matched noncreative controls on the Annett Hand Preference Questionnaire (HPQ), the Peters et al. Delusions Inventory, and the General Health Questionnaire. Creative artists were statistically more likely to admit the use of the left hand on the HPQ, with more widespread left hand use reported by artists involved in the creative activities traditionally associated with the right hemisphere (music and painting). They also scored higher on the Peters et al. Delusions Inventory independently from the level of psychopathology (measured with the General Health Questionnaire), from their laterality score (measured with the HPQ), and from their higher use of both licit and illicit drugs
Relationship between field line resonance at low geomagnetic latitudes and solar wind structures
No full textThe link between the pulsation activity in the local resonant band at a low latitude station and the macroscale structure of the interplanetary medium has been investigated. The experimental results show a clear dependence of the amplitude of the local resonant events on the interplanetary magnetic field magnitude and a preferable occurrence in correspondence of the compression regions preceding the high velocity solar wind streams. These features appear consistent with an upstream wave source for these events
Maximum entropy spectral analysis of artificial sinusoidal signals
No full textThe Burg's algorithm was applied to the spectral analysis of a signal that is the sum of 11 sinusoids as intermixed with different noise levels. Particular attention was paid to those features that for single sinusoids represent the crucial point of this technique and it was found that, for a multicomponent signal, the frequency shiftings are smaller than for single sinusoids and the splitting phenomena tend to occur at much higher orders of the prediction error filter. For a noise power smaller than 17% of the power of the lowest amplitude component, all the expected peaks were easily identified and most of the power was concentrated in very narrow ranges of frequency
Some theoretical aspects of the two-level magnetovariational method
No full textWe discuss some theoretical aspects of the two-level magnetovariational method for the determination of the underground electrical structure. The properties of two new apparent resistivity functions, respectively depending on gain and phase of the transfer function of the horizontal magnetic field variations between the Earth's surface and a given depth, are examined for two-layer Earth models. The effects of a finite wavelength of the source field are also investigated. It is shown that the measurement of the attenuation of the magnetic vertical component generated by an inhomogeneous source field can provide further information on the vertical distribution of the Earth's conductivity. In particular, it is shown that the measurement of the transfer function of both vertical and horizontal components between two levels can be used to estimate the average conductivity of the interlying medium.JCR Journalope
An analysis of solar wind fluctuations between 1 and 10 AU
No full textA cross-correlation analysis between different parameters of the solar wind plasma based on Voyager 1 and 2 data from 1 to 9.5 AU evidences, as a predominant feature of the microscale structure of the solar wind, a persistent presence of time periods characterized by high anticorrelation between the magnetic field magnitude and the proton density. These events are present at least 25% of the total time, and their frequency of occurrence progressively increases with increasing heliocentric distance. These results have been satisfactorily interpreted as being due to the presence of nonpropagating structures with internal pressure balance and characteristic time scale of ≲10 hours. Alfvénic fluctuations are confirmed to dominate the microscale at 1–2 AU, but they seem to become less important at larger heliocentric distances
Remote sensing of magnetospheric plasma mass density by ULF field line resonances: effects of using different magnetic field models
No full textA new meridional magnetometer array in middle-south Europe for monitoring dynamic processes in the coupled system plasmasphere-ionosphere
No full textPlasmasphere Refilling after the 1 June 2013 Geomagnetic Storm
Get PDFPlasma content and distribution are key parameters in the dynamics of the inner magnetosphere. The plasmasphere contributes, for the most part, to the plasma mass density, and its properties are very dependent on the history of the magnetosphere and geomagnetic activity. In this work, we investigated plasmasphere dynamics and plasmasphere–ionosphere coupling, focusing on the refilling process that followed the geomagnetic storm that occurred on 1 June 2013. The equatorial plasma mass density used to evaluate the refilling rates was remotely sensed by observation of the field line resonance (FLR) frequencies of the geomagnetic field, driven by ultra-low-frequency magnetic waves. The FLR frequencies were retrieved by performing an analysis of signals detected by several station pairs of the European quasi-Meridional Magnetometer Array. We estimated the rate at which the refilling process occurred, concentrating on both the diurnal and the day-to-day refilling rates. The estimated contraction rate during the main phase of the storm was higher than ∼3.5 REd−1, while the average expansion rate was ∼0.4 REd−1. We investigated the radial dependence of the refilling rates, using a novel approach based on fit plasma mass density profiles, and we related their variation to the plasmasphere boundary layer and the zero-energy Alfvén boundary. We found evidence supporting the idea that flux tubes mapping in the region between these two boundaries experience an enhanced refilling process
Comparison of equatorial plasma mass densities deduced from field line resonances observed at ground for dipole and IGRF models
No full textThe technique to remotely sense the plasma mass density in magnetosphere using field line resonance (FLR) frequencies detected by ground-based magnetometers has become more and more popular in the last few years. In this paper we examine the error that would be committed at low and middle latitudes (L < 4) in estimating the equatorial plasma mass density if dipole field lines are assumed instead of the more realistic representation given by IGRF field lines. It is found that the use of the centered dipole model may result in an error in the inferred density appreciably larger than what is usually assumed. In particular it has a significant longitudinal dependence being, for example, greater than +30% in the atlantic sector and about -30% at the opposite longitude sector for field lines extending to a geocentric distance of 2 Earth radii. This may result in an erroneous interpretation of the longitudinal variation in plasmaspheric density when comparing results from ground-based arrays located at different longitudes. We also propose simple modifications of the standard technique, such as the use of an effective dipole moment or the eccentric dipole model, which allow to keep using the dipole field geometry but with a significant error reduction
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