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Sensitivity to sounds is one frequent symptom of a sport-related concussion, but its assessment rarely goes beyond a single question. Here we examined sensitivity to sounds using psychoacoustic and psychometric outcomes in athletes beyond the acute phase of injury. Fifty-eight college athletes with normal hearing who either had incurred one or more sport-related concussions (N = 28) or who had never suffered head injury (N = 30) participated. Results indicated that the Concussed group scored higher on the Hyperacusis questionnaire and displayed greater sensitivity to sounds in psychoacoustic tasks compared to the Control group. However, further analyses that separated the Concussed group in subgroups with Sound sensitivity symptom (N = 14) and Without sound sensitivity symptom (N = 14) revealed that athletes with the sound complaint were the ones responsible for the effect: Concussed athletes with self-reported sound sensitivity had lower Loudness Discomfort Thresholds (LDLs), higher Depression and Hyperacusis scores, and shifted loudness growth functions compared to the other subgroup. A simple mediation model disclosed that LDLs exert their influence both directly on Hyperacusis scores as well as indirectly via depressive symptoms. We thus report a new clinical presentation of hyperacusis and discuss possible mechanisms by which it could arise from concussion.

We report on the resistivity (ρ), thermoelectric power (S for Seebeck) and magnetic measurements of the series Pr1-xCaxCrO3 (x=0.0–0.5). These orthochromites exhibit a T independent, large and positive S, from 100 K to 700 K which follows the Cr4+ concentration. Upon Ca2+ for Pr3+ substitution, a concomitant decrease of the resistivity and S values is found. The evolution of S as a function of hole concentration (Cr4+) can be nicely fitted by the modified Heikes formula which takes into account the orbital degeneracy associated to Cr3+/Cr4+. This is in good agreement with the model previously calculated by Marsh and Parris, in the case of weak magnetic coupling [Phys. Rev. B 54, 7720 (1996)]. The magnetic susceptibility measurements support the assumption of a weak magnetic coupling since the antiferromagnetic ordering TN values are found to be lower than 250 K. For Pr0.7Ca0.3CrO3, the power factor PF= S2/ρ measured at 700 K is equal to 1.9×10-4 W m-1K-2. The present system, chemically stable in air up to T > 1000 °C, is promising for thermoelectric application at very high temperature.

The substitution of 1%-Ce4 + for La3 + in LaCoO3 is found to change the sign of the Seebeck coefficient at room temperature. This demonstrates that not only holes but also electrons can be created in LaCoO3. The result is compatible with the Heikes formula for doping levels close to the “pure” trivalent Co3 + state. Nonetheless, the physical properties such as magnetic susceptibility, magnetization, thermal conductivity and resistivity are found to be asymmetric for hole and electron-doped LaCoO3. Such a different behaviour is ascribed to the very different spin-states of Co4 + (low-spin, t 2g 5 e g 0) and Co2 + (high-spin, t 2g 5 e g 2).

The magnetic properties of a polycrystalline Sr3NiIrO6 sample have been investigated by means of susceptibility and magnetization measurements. On the one hand, it is found that this compound, made of magnetic chains on a triangular lattice, behaves very similarly to Ca3CoRhO6 and Ca3CoIrO6. In particular, at low temperature ( T < T 2 ( = 21 K)), a frozen state, characterized by a very slow spin dynamic, is evidenced. On the other hand, for T 2 < T < T 1 ( = 70 K), this phase exhibits magnetization values, smaller than the expected ones, with a 1/3 plateau reminiscent of the ferrimagnetic state of Ising spins on a triangular lattice. Nonetheless, the absence of saturation in 35 T and the low magnetization values are consistent with an antiferromagnetic intrachain coupling between Ir4+ (S = 1/2) and Ni2+ (S = 1). Sr3NiIrO6 can be viewed as made of antiferromagnetically coupled ferrimagnetic chains on a triangular lattice. On the basis of these results, a magnetic (H, T) phase diagram is proposed.

The low temperature magnetic and transport properties of the Pr0.5Ca0.5Mn1-xNixO3 manganites ( 0≤x≤0.1) have been investigated. The presence of Ni hinders the charge and orbital ordering observed in Pr0.5Ca0.5MnO3 and favors the creation of ferromagnetic regions, leading to phase separation. The ferromagnetic fractions induced by the Ni substitution have been estimated from magnetization measurements, they are large and reach 40% for 4% of Ni. Steps are observed in the M(H) and ρ(H) curves of all the samples at T < 5 K. They are similar to the steps observed in Pr0.5Ca0.5Mn1-xMxO3, where M is a non magnetic cation (Mg2+, Ga3+,...), and for which the ferromagnetic fractions are very small (less than 2%), however, their appearance is restricted to lower temperatures (T < 5 K) with Ni dopant than with non magnetic cations. This study shows that steps can be observed in a wide range of phase-separated systems, even when the ferromagnetic fraction is very large.

The doping of the manganese site by iridium (up to 15%) in the small A cation manganites Pr_{1-x}Ca_xMnO_3 (0.4 < x < 0.8), has been investigated as a new method to suppress charge-ordering and induce CMR effects. Ir doping leads to ferromagnetism and to insulator to metal transitions, with high transition temperatures reaching 180K and CMR ratio in 7T as large as 10^4. The efficiency with which iridium induces ferromagnetism and CMR is compared to previous results obtained with other substitutions (Ru, Rh, Ni, Cr, ...). The ionic radius of the foreign cations and their mixed-valencies are found to be the main parameters governing the ability to collapse the charge-ordered state., 9 pages, 5 figures, accepted for publication in Eur. Phys. J. B

To investigate the existence of a splay effect in Bi2Sr2CaCu2O8 (Bi-2212), vortex pinning has been studied in different configurations of strongly inclined columnar defects (75 ° from the c axis), installed by heavy-ion irradiation. It is shown that the symmetry of the track setting with respect to the field direction is a more influent parameter than the presence of a dispersion in the track directions. We claim that the enhanced pinning efficiency which is observed in some splayed configurations of columnar defects in Bi-2212 can be interpreted without invoking a splay effect.

Pinning properties of (Bi/Pb)-2223 textured ceramics have been improved by 6 GeV Pb ions irradiation. Two samples were irradiated at fluencesφt=5 × 1010 ions/cm2 and 2 × 1011 ions/cm2, respectively. The magnetic irreversibility is clearly improved in the intermediate range of temperature: (30–35) K

The notion that the melody (i.e., pitch structure) of familiar music is more recognizable than its accompanying rhythm (i.e., temporal structure) was examined with the same set of nameable musical excerpts in three experiments. In Experiment 1, the excerpts were modified so as to keep either their original pitch variations, whereas durations were set to isochrony (melodic condition) or their original temporal pattern while played on a single constant pitch (rhythmic condition). The subjects, who were selected without regard to musical training, were found to name more tunes and to rate their feeling of knowing the musical excerpts far higher in the melodic condition than in the rhythmic condition. These results were replicated in Experiment 2, wherein the melodic and rhythmic patterns of the musical excerpts were interchanged to create chimeric mismatched tunes. The difference in saliency of the melodic pattern and the rhythmic pattern also emerged with a music-title-verification task in Experiment 3, hence discarding response selection as the main source of the discrepancy. The lesser effectiveness of rhythmic structure appears to be related to its lesser encoding distinctiveness relative to melodic structure. In general, rhythm was found to be a poor cue for the musical representations that are stored in long-term memory. Nevertheless, in all three experiments, the most effective cue for music identification involved the proper combination of pitches and durations. Therefore, the optimal code of access to long-term memory for music resides in a combination of rhythm and melody, of which the latter would be the most informative.

Splayed configurations of columnar defects with different characteristic angles θi relative to the $$\vec c$$ have been achieved in single crystals of YBCO, (Tl,Bi)-1212 and Bi-2212. An increased pinning efficiency consistents with the splayed model of Hwa et al, has been observed with θi=10° for YBCO and (Tl,Bi)-1212. For the more anisotropic compound Bi-2212, higher angles up to θi=75° are necessary to obtain the same result, but these last results are more delicate to interpret.

This series of experiments dealt with discrimination between two temporal patterns differing only by the insertion of an additional silent gap. In Experiment 1, patterns varied in metric and figural structure. Metric structure is described as the sense of temporal regularity that may occur between subjectively accented tones. Figural structure is described as the grouping of temporally adjacent tones separated by silences. Standard patterns were either strongly or weakly metric; comparison patterns differed from the standards by the insertion of a silence that disrupted either the metric structure alone or both the metric and the figural structures. Experiment 1 provided support for the roles of both metric and figural structures and provided support for the clock-induction model of Povel and Essens (1985) as an account of metric processing. In Experiments 2-4, discrimination of patterns with differing metric structures but identical figural structures was examined more closely. Rate of presentation of the patterns was varied. Multiple regression indicated that, independent of rate variations, discrimination improved as the absolute (not relative) duration of the silent gap increased. We argue that an additional timing mechanism, independent of pattern structure, is operative in temporal pattern discrimination. All the results were replicated across levels of music training of the listeners.