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Establishing normative values for 18-35 years age in neuropsychological tests used with head and brain injury patients during cognitive rehabilitation: Benton Visual Retention Test and National Adult Reading Test
The Benton Visual Retention Test (BVRT) is a neuropsychological assessment of visuo-spatial and visuo-memory ability. Claims of high reliability and validity are based on solitary samples representative of a wide age range. This study validated theBVRTagainst the National Adult Reading Test (NART), a highly validated and reliable test of estimated pre-morbid IQ in an age-specific group of participants (18-35 years).
Using Between-subjects factorial design, fifty-three participants (24 female, 29 male) aged 18-35 years (inclusive) were administered the NART and 3 administrations of the BVRT.
Significant positive correlations were found betweenBVRTError scores and NART Error scores for administrations B and C of theBVRTwhich is when presented stimuli are followed by a short time delay before allowing respondents to recall. Significant negative correlations were found over these administrations forBVRTCorrect scores and NART Error scores. No significant relationship was found between depression and performance on theBVRT. However, a weak, non-significant relationship was found between anxiety andBVRTperformance.
The BVRTis a well-validated and highly reliable neuropsychological test of visuo-spatial and visuo-memory abilities. Findings provide new data for the 18-35 years age group as well as providing a cautionary note on the possible influence of anxiety on performance levels in light of the frequent occurrence of anxiety post-neurological injury
Haze in the Mars atmosphere as revealed by the Mariner 4 television data
Photometric investigation of haze in Mars atmosphere revealed by Mariner 4 television dat
Diurnal variation in harbour porpoise detection – potential implications for management
Peer reviewedPublisher PD
Spectral Line Broadening and Angular Blurring due to Spacetime Geometry Fluctuations
We treat two possible phenomenological effects of quantum fluctuations of
spacetime geometry: spectral line broadening and angular blurring of the image
of a distance source. A geometrical construction will be used to express both
effects in terms of the Riemann tensor correlation function. We apply the
resulting expressions to study some explicit examples in which the fluctuations
arise from a bath of gravitons in either a squeezed state or a thermal state.
In the case of a squeezed state, one has two limits of interest: a coherent
state which exhibits classical time variation but no fluctuations, and a
squeezed vacuum state, in which the fluctuations are maximized.Comment: 21 pages, 2 figures. Dedicated to Raphael Sorkin on the occasion of
his 60th birthday. (v2: several references added and some minor errors
corrected
Millipeds (Arthropoda: Diplopoda) of the Ark - La - Tex. VI. New Geographic Distributional Records from Select Counties of Arkansas
We continue to report, in the sixth of a series of papers, new geographic records for millipeds of the state, including noteworthy records for some taxa collected from Crowley’s Ridge in eastern Arkansas. This contribution documents 47 new co. records and includes records for 19 species within 9 families and 5 orders. More uncommon millipeds found included Okliulus carpenteri (Parajulidae), Eurymerodesmus newtonus (Eurymerodesmidae), Pseudopolydesmus minor (Polydesmidae) and undescribed species of Ethojulus (Parajulidae) and Nannaria (Xystodesmidae). Undoubtedly, additional records will be reported in the future as several gaps in the distribution of Arkansas millipeds remain
The Fourier coefficients of Eisenstein series newforms
In this article, we study the Fourier coefficients of Eisenstein series newforms. We obtain a sharp refinement of the strong multiplicity-one theorem by showing that the density of primes p for which the pth Hecke eigenvalues of two distinct Eisenstein series newforms differ is of the form 1/n for some n ≥ 2. Additionally, we show that if f is an Eisenstein series newform whose Fourier coefficients af (n) are real then there is a constant δ > 0 such that the sequence (af (n))n≤x has at least δx sign changes
Start to end simulations of the ERL prototype at Daresbury Laboratory
Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that will serve as a research and development facility for the study of beam dynamics and accelerator technology important to the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives of the ERLP are the demonstration of energy recovery and of energy recovery from a beam disrupted by an FEL interaction as supplied by an infrared oscillator system. In this paper we present start-to-end simulations of the ERLP including such an FEL interaction. The beam dynamics in the highbrightness injector, which consists of a DC photocathode Gun and a superconducting booster, have been modelled using the particle tracking code ASTRA. After the booster the particles have been tracked with the code elegant. The 3D code GENESIS 1.3 was used to model the FEL interaction with the electron beam at 35 MeV. A brief summary of impedance and wakefield calculations for the whole machine is also given
Electrodynamics of Magnetars IV: Self-Consistent Model of the Inner Accelerator, with Implications for Pulsed Radio Emission
We consider the voltage structure in the open-field circuit and outer
magnetosphere of a magnetar. The standard polar-cap model for radio pulsars is
modified significantly when the polar magnetic field exceeds 1.8x10^{14} G.
Pairs are created by accelerated particles via resonant scattering of thermal
X-rays, followed by the nearly instantaneous conversion of the scattered photon
to a pair. A surface gap is then efficiently screened by e+- creation, which
regulates the voltage in the inner part of the circuit to ~10^9 V. We also
examine the electrostatic gap structure that can form when the magnetic field
is somewhat weaker, and deduce a voltage 10-30 times larger over a range of
surface temperatures. We examine carefully how the flow of charge back to the
star above the gap depends on the magnitude of the current that is extracted
from the surface of the star, on the curvature of the magnetic field lines, and
on resonant drag. The rates of different channels of pair creation are
determined self-consistently, including the non-resonant scattering of X-rays,
and collisions between gamma rays and X-rays. We find that the electrostatic
gap solution has too small a voltage to sustain the observed pulsed radio
output of magnetars unless i) the magnetic axis is nearly aligned with the
rotation axis and the light of sight; or ii) the gap is present on the closed
as well as the open magnetic field lines. Several properties of the radio
magnetars -- their rapid variability, broad pulses, and unusually hard radio
spectra -- are consistent with a third possibility, that the current in the
outer magnetosphere is strongly variable, and a very high rate of pair creation
is sustained by a turbulent cascade.Comment: 32 pages, submitted to the Astrophysical Journa
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