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Hyperacusis is known as a reduced tolerance to sounds perceived as normal to the majority of the population. There is currently no agreed definition, diagnostic tool, or objective measure of its occurrence. The purpose of this review is to catalogue the research to date on the use of auditory evoked potentials (AEP) to assess hyperacusis.A step-by-step methodology was conducted following guidelines. Four databases were searched. A total of 3343 papers were identified. A final yield of 35 articles were retained for analysis.The analysis identified four types of aetiologies to describe the hyperacusic population in AEP studies; developmental disorders (The results of this review revealed the potential use of electrophysiological measures for further understanding the mechanisms of hyperacusis. However, according to the disparity of concepts to define hyperacusis, definitions and populations need to be clarified before biomarkers specific to hyperacusis can be identified.

International audience; Thermoelectric performance largely depends on the reduction of lattice thermal conductivity (κL). The study of the thermal conductivity (κ) of a Sb2Te3/graphite nanocomposite system demonstrates ∼40% reduction in κL with graphite incorporation. A plausible explanation of intrinsic low κL observed in Sb2Te3 based system is presented by modeling experimental specific heat (Cp) data. Raman spectroscopy measurement combined to X-Ray diffraction data confirms the presence of graphite as separate phase in the composite sample. It is found that phonon scattering dominates heat transport mechanism in the nanostructured Sb2Te3/graphite composite. Large reduction in κL is accomplished by intensifying scattering rate of phonons via various sources. Graphite introduces effective scattering sources, i.e., defects of different dimensionalities in synthesized nanocomposite sample. Furthermore, graphite mediates phonon-phonon coupling and enhances lattice anharmonicity, which causes an intrinsic scattering of phonons with all frequencies in the Sb2Te3/graphite nanocomposite sample. Dislocation density and phonon anharmonicity of the synthesized samples are estimated from in depth analysis of temperature dependent synchrotron powder diffraction and Raman spectroscopic data. κL value as low as 0.8 W m−1K−1 at 300 K, achieved with graphite dispersion in Sb2Te3 based composite system makes the present comprehensive study an interesting concept to be developed in thermoelectric materials.

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International audience; A Co9S8 dense ceramic sintered by spark plasma sintering has been characterized by X-ray powder diffraction and transmission electron microscopy (diffraction and high resolution). This allowed magnetic, electronic, and thermal transport measurements to be made for a cubic (a = 9.927(2)Å) Co9S8 sample free of impurities and structural defects. The magnetic susceptibility and magnetic field dependence of the magnetization point toward an antiferromagnetic state, whereas the four-probe resistivity reveals a very metallic behavior with ρ300 K = 80 μΩ.cm described by a classical electron phonon model. When compared to CoS2, even if Co9S8 exhibits lower ρ values associated with the lack of ferromagnetic fluctuations existing in the former, the Co9S8 thermoelectric power factor, negative as in CoS2, is smaller, nonetheless leading to a power factor (PF) reaching PF ≈ 0.5 mW m–1 K–2 at 300 K. In Co9S8, with its low ρ going with a very high electronic part of the thermal conductivity κ, the lattice part of κ is smaller than that of CoS2 (∼2 W m–1 K–1 for Co9S8 at 300 K) suggesting that the more complex structure of Co9S8, with two different types of CoSn polyhedra, plays an important role.

International audience; The thermal conductivity of crystalline materials cannot be arbitrarily low, as the intrinsic limit depends on the phonon dispersion. We used complementary strategies to suppress the contribution of the longitudinal and transverse phonons to heat transport in layered materials that contain different types of intrinsic chemical interfaces. BiOCl and Bi2O2Se encapsulate these design principles for longitudinal and transverse modes, respectively, and the bulk superlattice material Bi4O4SeCl2 combines these effects by ordering both interface types within its unit cell to reach an extremely low thermal conductivity of 0.1 watts per kelvin per meter at room temperature along its stacking direction. This value comes within a factor of four of the thermal conductivity of air. We demonstrated that chemical control of the spatial arrangement of distinct interfaces can synergically modify vibrational modes to minimize thermal conductivity.

The magnetism, magnetotransport, and Seebeck coefficients $(S)$ for three ruthenates ${\mathrm{Ba}}_{1\ensuremath{-}\ensuremath{\delta}}{M}_{2+x}{\mathrm{Ru}}_{4\ensuremath{-}x}{\mathrm{O}}_{11}$ $(\ensuremath{\delta}=0.06;$ $M=\mathrm{Mn}, \mathrm{Co}; x=0.4)$ and ${\mathrm{Sr}}_{1\ensuremath{-}\ensuremath{\delta}}{M}_{2+x}{\mathrm{Ru}}_{4\ensuremath{-}x}{\mathrm{O}}_{11}$ $(\ensuremath{\delta}=0.02; M=\mathrm{Fe}; x=0.7)$ compositions have been studied. Their crystallographic structures contain three metal sites, edge-sharing octahedra forming kagome lattices, face-shared octahedra with the shortest $\mathrm{Ru}(M)\text{\ensuremath{-}}\mathrm{Ru}(M)$ distance, and ${M\mathrm{O}}_{5}$ trigonal bipyramids. These three compositions have been selected for their transport behavior exhibiting small resistivity values (\ensuremath{\sim}m\ensuremath{\Omega} cm) together with a complex ferrimagnetic behavior, with localization increasing from $M=\mathrm{Co}$ to $M=\mathrm{Fe}$. This enabled the thermopower to be measured in hexagonal ruthenates in which the conducting kagome layers are more or less diluted by three different magnetic cations substituted for Ru. The positive Seebeck coefficient of the three compounds is found to increase up to 750 K to values in the range of 22 to $35\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{V}\phantom{\rule{4pt}{0ex}}{\mathrm{K}}^{\text{--}1}$. Such values, similar to those of perovskite ruthenates, reveal a Seebeck coefficient dominated by the Ru network at high temperature whatever the foreign magnetic cation is. In addition, below about 50 K, the values of $S$ are very small for $M=\mathrm{Mn}$ and Co, and the $S(T)$ curves of the ${\mathrm{Ba}}_{1\ensuremath{-}\ensuremath{\delta}}{M}_{2.4}{\mathrm{Ru}}_{3.6}{\mathrm{O}}_{11}$ compounds exhibit similarities with that of ruthenium metal. This is interpreted by shorter Ru-Ru distances as compared with perovskite ruthenates allowing a metallic direct exchange. The ferrimagnetism associated with the $M$ cation does not seem to play a major role in transport, as there is almost no impact of the magnetic ordering on thermopower and electrical resistivity and the values of magnetoresistance remain very small, reaching at most \ensuremath{-}1% in 9 T at 5 K for $M=\mathrm{Mn}$, and \ensuremath{-}0.4% at ${T}_{\mathrm{C}}$ for $M=\mathrm{Co}$. The present results obtained in these phases containing hexagonal Ru networks show that Hund's metal model developed to describe the thermopower of perovskite ruthenates with a Ru square lattice can have a broader range of validity.

International audience; Magneto-caloric materials offer the possibility to design environmentally friendlier thermal management devices compared to the widely used gas-based systems. The challenges to develop this solid-state based technology lie in the difficulty of finding materials presenting a large magneto-caloric effect over a broad temperature span together with suitable secondary appli-cation parameters such as low heat capacity and high thermal conductivity. A series of compounds derived from the PbFCl structure is investigated using a combination of computational and experimental methods focusing on the change of cell volume in magnetic and non-magnetic ground states. Scaling analysis of the magnetic properties determines that they are second order phase transition ferromagnets and that the magnetic entropy change is driven by the coupling of magneto-elastic strain in the square-net through the magnetic transition determined from neutron and synchrotron X-ray diffraction. The primary and secondary application related properties are measured experimentally, and the c/a parameter is identified as an accurate proxy to control the magnetic transition. Chemical substitution on the square-net affords tuning of the Curie temperature over a broad temperature span between 252 and 322 K. A predictive machine learning model for the c/aparameter is developed to guide future exploratory synthesis.

Neutron diffraction and x-ray pair distribution function experiments were performed to investigate the magnetic and local crystal structures of ${\mathrm{Ba}}_{2}\mathrm{FeSb}{\mathrm{Se}}_{5}$ and to compare them with the average (i.e., long range) structural model previously obtained by single-crystal x-ray diffraction. Changes in the local crystal structure (i.e., in the second coordination sphere) are observed upon cooling from 295 to 95 K, resulting in deviations from the average (i.e., long range) crystal structure. In this paper, we demonstrate that these observations cannot be explained by local or long-range magnetoelastic effects involving Fe-Fe correlations. Instead, we found that the observed differences between local and average crystal structure can be explained by Sb-$5s$ lone pair dynamics. We also find that, below the N\'eel temperature $({T}_{N}=58\phantom{\rule{0.16em}{0ex}}\mathrm{K})$, the two distinct magnetic ${\mathrm{Fe}}^{3+}$ sites order collinearly, such that a combination of antiparallel and parallel spin arrangements along the $b$ axis results. The nearest-neighbor arrangement $({J}_{1}=6\phantom{\rule{0.16em}{0ex}}\AA{})$ is fully antiferromagnetic, while next-nearest-neighbor interactions are ferromagnetic in nature.

In this chapter, I address the topic of tinnitus in the context of the patient's trajectory of care, with special attention to psychological comorbidities. Although most patients will cope with tinnitus and need no more than information and reassurance from professionals, a proportion of patients will need more supportive management. Assessment of psychological comorbidities is important to determine how urgent they should be seen in the clinic and their specific needs. The most frequent complaints are stress, depression, and anxiety. Although the direction of this relationship is still unclear (are comorbidities at the origin of tinnitus or are they a consequence of it), it is evident that the more serious comorbidities are at the onset of tinnitus, the worse the prognosis. Therefore, an assessment at the initial visit in the clinic is of utmost importance. There are valid and reliable psychometric tools to quickly draw a portrait of the psychological state of patients that can be used by audiologists, psychologists, or doctors. Therapeutic avenues can then be discussed with the patients to ensure them the best support possible.

In this chapter, I address the topic of tinnitus in the context of the patient's trajectory of care, with special attention to psychological comorbidities. Although most patients will cope with tinnitus and need no more than information and reassurance from professionals, a proportion of patients will need more supportive management. Assessment of psychological comorbidities is important to determine how urgent they should be seen in the clinic and their specific needs. The most frequent complaints are stress, depression, and anxiety. Although the direction of this relationship is still unclear (are comorbidities at the origin of tinnitus or are they a consequence of it), it is evident that the more serious comorbidities are at the onset of tinnitus, the worse the prognosis. Therefore, an assessment at the initial visit in the clinic is of utmost importance. There are valid and reliable psychometric tools to quickly draw a portrait of the psychological state of patients that can be used by audiologists, psychologists, or doctors. Therapeutic avenues can then be discussed with the patients to ensure them the best support possible.

Investigation into the thermoelectric properties of oxides in the last 20 years has shown that optimization of thermoelectric power depends on original parameters that cannot be simply described by Boltzmann transport equations, as the entropy part of the Seebeck coefficient (S) plays a major role. The optimization of S strongly depends on carrier doping and also on the specific orbital filling of these carriers, on the presence of electronic correlations, and on carrier spins and magnetic exchanges between them. The peculiarities observed mostly in p-type oxides are presented here, and the Seebeck coefficient in different ruthenium oxides will be discussed. In these ruthenates with different crystallographic structures and electronic and magnetic ground states, and for which spin-orbit coupling plays a major role, the Seebeck coefficient is shown to converge toward a common value at very high temperatures, which depends on the spin entropy only. This highlights the dominant role of entropy in these p-type oxides, and demonstrates how spin and magnetism can strongly affect the thermopower of oxides. Recent results have shown that apart from oxides, magnetism can also be a tuning parameter in other chalcogenides such as sulfides.

This volume has highlighted the many recent advances in tinnitus theory, models, diagnostics, therapies, and therapeutics. But tinnitus knowledge is far from complete. In this chapter, contributors to the Behavioral Neuroscience of Tinnitus consider emerging topics and areas of research needed in light of recent findings. New research avenues and methods to explore are discussed. Issues pertaining to current assessment, treatment, and research methods are outlined, along with recommendations on new avenues to explore with research.

Tinnitus and hyperacusis are two debilitating conditions that are highly comorbid. It has been postulated that they may originate from similar pathophysiological mechanisms such as an increase in central gain. Interestingly, sound stimulation has been shown to reduce central gain and is currently used for the treatment of both conditions. This study investigates the effect of sound stimulation on both tinnitus and hyperacusis in the same patients. Two distinct series of tinnitus participants were tested: one with normal or near-normal hearing (n = 16) and one with hearing loss (n = 14). A broadband noise shaped to cover most of the tinnitus frequency spectrum was delivered through hearing aids using the noise generator feature (no amplification) and verified through real-ear measurements. Participants received sound stimulation for 3 weeks and were tested before (at baseline), then after 1 week and at the end of the 3 weeks of sound stimulation. There was also a 1-month follow-up after the end of the stimulation protocol. The measurements included self-reported measures of tinnitus and hyperacusis (VAS), validated questionnaires (THI, HQ) and psychoacoustic measurements (tinnitus battery and loudness functions). On both self-assessment (VAS of sound tolerance and tinnitus loudness) and psychoacoustic measures (loudness function and tinnitus loudness in dB), about 50% of tinnitus participants had a synchronous (either a decrease or an increase) modulation of hyperacusis and tinnitus loudness after 1 week and 3 weeks of acoustic stimulation and up to about 70% of participants at 1-M follow-up. The decrease of hyperacusis and tinnitus loudness was more prevalent in normal-hearing participants. There was a significant increase in tinnitus loudness during and following the stimulation in the group with hearing loss. Hyperacusis improvement as assessed by loudness function was significantly correlated with the intensity level of the acoustic stimulation (dB level of the noise produced by the noise generator) in tinnitus participants with normal/near-normal hearing thresholds. Our study partly supports the central gain hypothesis by showing synchronous modulation of hyperacusis and tinnitus loudness. It also shows beneficial effects of acoustic stimulation in some tinnitus individuals, in particular those with normal or near-normal hearing, while highlighting the importance of a careful fitting of sound generators to prevent increase. Since the amplification feature was not turned on in our study, future work should determine whether amplification alone, or in addition to acoustic stimulation (sound generators), would benefit to those with hearing loss.

The results showed a trend of increased post-gap amplitudes and reduced gap salience; however, the small number of articles yield and limited consensus prohibit any conclusions for clinical use. Nevertheless, gap-induced EPs may be further explored as a potential tool for tinnitus detection.

The Gap Prepulse Inhibition of the Acoustic Startle Reflex (GPIAS) is a paradigm used to assess auditory temporal processing in both animals and humans. It consists of the presentation of a silent gap embedded in noise and presented a few milliseconds before a startle sound. The silent gap produces the inhibition of the startle reflex, a phenomenon called gap-prepulse inhibition (GPI). This paradigm is also used to detect tinnitus in animal models. The lack of inhibition by the silent gaps is suggested to be indicative of the presence of tinnitus "filling-in" the gaps. The current research aims at improving the GPIAS technique by comparing the GPI produced by monaural versus binaural silent gaps in 29 normal-hearing subjects. Two gap durations (5 or 50 ms), each embedded in two different frequency backgrounds (centered around 500 or 4 kHz). Both low- and high- frequency narrowband noises had a bandwidth of half an octave. Overall, the startle magnitude was greater for the binaural versus the monaural presentation, which might reflect binaural loudness summation. In addition, the GPI was similar between the monaural and the binaural presentations for the high-frequency background noise. However, the GPI was greater for the low-frequency background noise for the binaural, compared to the monaural, presentation. These findings suggest that monaural GPIAS might be more suited to detect tinnitus compared to the binaural presentation.

The dynamic and static magnetic properties of Ga0.99Yb0.01FeO3 are studied in detail using ac susceptibility and dc magnetization measurements. The study shows that the compound undergoes a spin-glass freezing at T g ≈ 213 K . The dynamic scaling analysis of ac susceptibility data reveals typical features characteristic of canonical spin-glasses, i.e., relaxation time τ ∗ ∼ 10 - 14 s , critical exponent ν z = 4.1 ± 0.2 , and frequency sensitivity parameter δ f ∼ 10 - 3 within three frequency decades. The analysis of the critical behaviour of the static nonlinear susceptibility yields the critical exponents γ = 4.3 ± 0.1 , β = 1.0 ± 0.1 , and δ = 5.5 ± 0.5 , which lie between those typical of three-dimensional (3D) weakly anisotropic Heisenberg and Ising spin glasses. The analysis of the field-cooled and zero-field-cooled magnetization data allows to define two characteristic temperatures depending on the applied magnetic field. The upper one, T irr H , is the threshold temperature corresponding to the appearance of weak irreversibility, whereas the lower one, T s H , marks the onset of strong irreversibility. The resulting field-temperature phase diagram turns out to be in good quantitative agreement with the mean-field predictions for 3D Heisenberg spin-glass with random magnetic anisotropy, and appears consistent with the chiral driven freezing scenario.

We have studied the electronic structure of ${\mathrm{BaCoO}}_{3}$ using soft x-ray absorption spectroscopy at the Co ${L}_{2,3}$ and O $K$ edges, magnetic circular dichroism at the Co ${L}_{2,3}$ edges, and valence band hard x-ray photoelectron spectroscopy. The quantitative analysis of the spectra established that the Co ions are in the formal low-spin tetravalent $3{d}^{5}$ state and that the system is a negative charge transfer Mott insulator. The spin-orbit coupling also plays an important role for the magnetism of the system. At the same time, a trigonal crystal field is present with sufficient strength to bring the $3{d}^{5}$ ion away from the ${J}_{\mathrm{eff}}=1/2$ state. The sign of this crystal field is such that the ${a}_{1g}$ orbital is doubly occupied, explaining the absence of a Peierls transition in this system, which consists of chains of face-sharing ${\mathrm{CoO}}_{6}$ octahedra. Moreover, with one hole residing in ${e}_{g}^{\ensuremath{\pi}}$, the presence of an orbital moment and strong magnetocrystalline anisotropy can be understood. Yet we also infer that crystal fields with lower symmetry must be present to reproduce the measured orbital moment quantitatively, thereby suggesting the possibility for orbital ordering to occur in ${\mathrm{BaCoO}}_{3}$.

The $\mathrm{N}{\mathrm{i}}_{1\ensuremath{-}x}\mathrm{C}{\mathrm{u}}_{x}{\mathrm{S}}_{2}$ pyrite ($x\ensuremath{\le}0.07$) is a model material where the impact of electron filling on a half-filled ${e}_{\mathrm{g}}$ band system can be separated from changes in the bandwidth, since the unit cell volume does not change with $x$. This contrasts with the $\mathrm{Ni}{\mathrm{S}}_{2\ensuremath{-}x}\mathrm{S}{\mathrm{e}}_{x}$ system where the size difference between ${\mathrm{S}}^{2\ensuremath{-}}$ and $\mathrm{S}{\mathrm{e}}^{2\ensuremath{-}}$ makes the bandwidth vary at constant band filling. Our magnetic measurements show that there exists a clear relation between the presence of the antiferromagnetic phase developing below ${T}_{\mathrm{N}2}=29.75\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ and charge localization. With the addition of Cu in $\mathrm{N}{\mathrm{i}}_{1\ensuremath{-}x}\mathrm{C}{\mathrm{u}}_{x}{\mathrm{S}}_{2}$, the ground state evolves towards a metallic paramagnetic state. These findings are discussed with the scenario based on charge ordering at low temperature in the charge transfer insulator $\mathrm{Ni}{\mathrm{S}}_{2}$ pyrite, and also considering possible conducting surface states at low temperatures. At 300 K, the thermal conductivity decreases by 2.5 as $x$ increases from 0.00 to 0.07, even though the latter is much more electrically conductive than the former. This considerably extends the range of values for the thermal conductivity of the $\mathrm{M}{\mathrm{S}}_{2}$ pyrites, from the largest in $\mathrm{Fe}{\mathrm{S}}_{2}$ to the lowest in the present $\mathrm{N}{\mathrm{i}}_{1\ensuremath{-}x}\mathrm{C}{\mathrm{u}}_{x}{\mathrm{S}}_{2}$ samples.

Polycrystalline Sr2Fe1+xRe1-xO6 samples have been synthesized and structurally characterized by X-ray powder diffraction, transmission electron microscopy and X-ray absorption spectroscopy. Resistivity strongly increases with x, but a large and negative magnetoresistance persists up to x = 0.33. This is discussed considering the charge delocalization in iron and rhenium t2g orbitals. Fil: Maignan, Antoine. Ecole Nationale Superieure D'ingenieurs de Caen; Francia Fil: Martin, Christine. Ecole Nationale Superieure D'ingenieurs de Caen; Francia Fil: Lebedev, Oleg. Ecole Nationale Superieure D'ingenieurs de Caen; Francia Fil: Sottmann, Jonas. Ecole Nationale Superieure D'ingenieurs de Caen; Francia Fil: Nataf, Lucie. Soleil Synchrotron; Francia Fil: Baudelet, François. Soleil Synchrotron; Francia Fil: Hébert, Sylvie. Soleil Synchrotron; Francia Fil: Carbonio, Raul Ernesto. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina

Polycrystalline Sr2Fe1+xRe1-xO6 samples have been synthesized and structurally characterized by X-ray powder diffraction, transmission electron microscopy and X-ray absorption spectroscopy. Resistivity strongly increases with x, but a large and negative magnetoresistance persists up to x = 0.33. This is discussed considering the charge delocalization in iron and rhenium t2g orbitals.

International audience; Magnetic structure of CaFe5O7 ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: TM=125 K and TN=360 K. The latter corroborates the structural monoclinic-orthorhombic transition previously reported by transmission electron microscopy techniques and X-ray thermodiffractometry. Complementary heat capacity measurements have confirmed this first order transition with a sharp peak at 360 K. Interestingly, this large study has revealed a second magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe2O3 hematite at TM=260 K.

Background: Aphasia challenges the functional communication abilities that people use for everyday social interaction. People with non-fluent aphasia struggle to express themselves when speaking, yet they have been shown to better pronounce words when singing familiar songs or novel songs in a choral context. Choral singing and familiar songs are at the core of choir practice, a recreational activity that has long been offered in aphasic associations. Beneficial effects of this activity have been suggested for aphasia rehabilitation but have never been tested in a randomised controlled trial (RCT).Aim: Our study addressed whether the process of such a study is feasible and aimed to provide the first controlled trial of the effects of choir practice on aphasia rehabilitation.Methods: We piloted a three armed-prospective, randomised, parallel-group, open-label, blinded end point (PROBE) pragmatic study with a 1:1:1 allocation ratio and stratification for aphasia severity. The primary outcome was imp...

We present a study of the thermal transport in thin single crystals of iron-intercalated titanium disulphide, ${\mathrm{Fe}}_{x}{\mathrm{TiS}}_{2}$, for $0\ensuremath{\le}x\ensuremath{\le}0.20$. We determine the distribution of intercalants using high-resolution crystallographic and magnetic measurements, confirming the insertion of Fe without long-range ordering. We find that iron intercalation perturbs the lattice very little, and suppresses the tendency of ${\mathrm{TiS}}_{2}$ to self-intercalate with excess Ti. We observe trends in the thermal conductivity that are compatible with our ab initio calculations of thermal transport in perfectly stoichiometric ${\mathrm{TiS}}_{2}$.

International audience; The magnetic and transport properties of two hollandites, Sr1.5Ru6.1Cr1.9O16 and Ba1.5Ru6.1Cr1.9O16, crystallizing in the I4/m space group, have been investigated. The structural study shows a lack of cation ordering, and the mixed Cr and Ru occupation in the edge shared MO6 octahedra is responsible for magnetic and electrical transport properties dominated by the localized nature of the carriers, in clear contrast with the metallic and Pauli magnetism observed in ruthenium hollandites. In particular, a complex magnetic behavior together with a cluster-glass behavior and semi-conducting resistivity are observed. Interestingly, both compounds exhibit negative magneto-resistance, reaching −18.6% at 5 K and 9 T in Ba1.5Ru6.1Cr1.9O16, and −4% in Sr1.5Ru6.1Cr1.9O16. This magneto-resistance is directly associated with the variable-range hopping nature of transport and hence with the existence of localized carriers induced by the Cr for Ru substitution. In contrast, the thermopower at high temperature shows a behavior dominated by the Ru cation network, with S ∼ 30 μV K−1, consistent with those measured for other ruthenates such as SrRuO3 and CaCu3Ru4O12 quadruple perovskites, or in the KRu4O8 hollandite. The comparison of these two hollandites with the KRu4O8 hollandite enables a direct investigation of the impact of localization on the thermopower in these materials.

Objectives It is well recognized that tinnitus can severely interfere with important aspects of life such as sleep, concentration abilities, social activities, and mood. However, the impact of tinnitus may vary greatly from one individual to another, with some being severely affected and others only experiencing a slight handicap. Information from participants' experiences with tinnitus could help explain such variability. The full experience of living with tinnitus from a patient's perspective has been under-investigated, especially in comparison with the large and extensive body of qualitative research on hearing loss. This study aims to contribute to fill this gap and assess participants' experience of living with tinnitus. Design As part of a larger mixed design study, this inquiry used qualitative analyses to investigate participant's experiences with tinnitus. Twenty-seven tinnitus participants of different ages, sexes, audiometric profiles, and tinnitus severities were invited to discuss their tinnitus through semistructured interviews and journal entries. The interviews took place 1 month after participants completed a 3-week trial period with tinnitus maskers. Results The findings were grouped into three main themes: participants' appraisal of their tinnitus, factors modulating tinnitus experience, and consequences of tinnitus. Regarding participants' appraisal of their tinnitus, a dissociation between the tinnitus sensation (pitch, loudness) and tinnitus experience (annoyance/distress) was reported. Factors modulating tinnitus experience were classified as environmental factors and individual-specific factors, which were further divided into soundscape and other environmental factors for the former and attentional focus, stress level, physical state, fatigue, and auditory effort for the latter. Consequences of tinnitus included distraction, disrupted mental health and mood, headaches, fatigue, sleep disturbances, hearing difficulties, disrupted social life, and frustration. Conclusions Two of the main themes (participants' appraisal of their tinnitus and consequences of tinnitus) were consistent with findings from a few previous qualitative studies. Factors modulating tinnitus experience also emerged as a prominent theme. Indeed, participants described a plethora of factors that affected their experiences of tinnitus. On the basis of these findings, an attentional model is proposed to account for how these factors might modulate the effects of tinnitus.

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.

The gap-prepulse inhibition of the acoustic startle (GPIAS) paradigm is the primary test used in animal research to identify gap detection thresholds and impairment. When a silent gap is presented shortly before a loud startling stimulus, the startle reflex is inhibited and the extent of inhibition is assumed to reflect detection. Here, we applied the same paradigm in humans. One hundred and fifty-seven normal-hearing participants were tested using one of five gap durations (5, 25, 50, 100, 200 ms) in one of the following two paradigms-gap-embedded in or gap-following-the continuous background noise. The duration-inhibition relationship was observable for both conditions but followed different patterns. In the gap-embedded paradigm, GPIAS increased significantly with gap duration up to 50 ms and then more slowly up to 200 ms (trend only). In contrast, in the gap-following paradigm, significant inhibition-different from 0--was observable only at gap durations from 50 to 200 ms. The finding that different patterns are found depending on gap position within the background noise is compatible with distinct mechanisms underlying each of the two paradigms.

International audience; We report a new synthesis route towards polycrystalline Ba(2)FePnSe(5) (Pn = Sb, Bi) chalcogenides based on ball milling and subsequent spark plasma sintering. The polycrystalline samples were characterized by transmission electron microscopy and powder X-ray diffraction. We discovered that both compounds undergo rapid, radiation induced phase changes between a crystalline and an amorphous phase. Thin layers of amorphous Ba(2)FePnSe(5) (Pn = Sb, Bi) were obtained by applying 0.3 ms laser pulses (lambda = 1064 nm) on the surface of polycrystalline samples. By using a series of subsequent laser pulses at room temperature the surface of Ba2FeBiSe5 can be reversibly changed between amorphous and crystalline states. The thermal conductivity can be used to follow the amorphization and recrystallization processes as a function of laser pulses. Resistivity measurements and calculations of the electronic structure revealed band gaps of 1.04 eV (Pn = Bi) and 1.14 eV (Pn = Sb). We found anomalies in the thermal conductivity of Ba(2)FePnSe(5) (Pn = Sb, Bi) at the Neel temperature due to the antiferromagnetic ordering of the Fe spins. We also show that the distortion of the PnSe(6) octahedra is caused by stereoactive 5s(2) and 6s(2) lone pairs of Sb and Bi. (C) 2017 Elsevier B.V. Ail rights reserved.

International audience; The transport properties of the thiospinel CuCrTiS4 have been investigated in detail, focusing on the possible interplay between charges and spins, and its consequence on transport, and more specifically on the thermoelectric properties. The chemical homogeneity of a CuCrTiS4 polycrystalline sample synthesized by a direct reaction of the constitutive elements has been carefully probed by X-ray diffraction and transmission electron microscopy techniques. This thiospinel exhibits below 75 K, in its paramagnetic regime, a variable range hopping (VRH) conduction, associated with a giant magnetoresistance (MR), which persists below the spin-glass transition temperature at 8K, reaching -95% in 9 T at 5K. All the MR data can be rescaled as a function of H/T and described using a Brillouin function with S = 3/2. This demonstrates that the paramagnetic fluctuations strongly impact the transport properties, and this is confirmed by the Seebeck coefficient which depends on the magnetic field at low temperature, with a large negative magnetothermopower (MTEP) effect of -26% at 20 K, i.e., the thermopower is reduced as the spin alignment reduces the spin entropy. This first report of MTEP in CuCrTiS4 shows that this thiospinel behaves rather similarly to strongly correlated oxides, with MR and MTEP enhanced in the case of VRH transport with paramagnetic spins, such as in cobalt misfits or colossal MR manganites. Published by AIP Publishing.

International audience; The crystal structure of single crystalline members of the solid solution series Tl(V1-xCrx)5Se8 (x = 0-1 and Δx = 0.2) was determined and the magnetic and thermoelectric properties of bulk TlV5Se8 were investigated. All compounds crystallize in the pseudo-hollandite-type structure (C2/m) with a nonlinear increase in the unit cell volume due to a simultaneous increase/decrease in the transition metal distances across the edge/face-sharing octahedra. A slight Tl deficiency was found for single crystalline TlV5Se8 and Tl(V0.8Cr0.2)5Se8 as well as for bulk TlV5Se8 according to Rietveld and single crystal structure refinements. The metallic character of bulk TlV5Se8 and its low electrical resistivity compared to poly- and single-crystalline TlCr5Se8 can probably be associated with this probable Tl deficiency. In TlV5Se8, anomalies in the low temperature Seebeck coefficient, i.e. a maximum at T ∼ 14 K and two sign changes at T ∼ 47 K and T ∼ 167 K, were found. Bulk TlV5Se8 is a highly frustrated (f = /TN ≈ 42 K) Curie-Weiss paramagnet ordering antiferromagnetically ( = -1287 K) below TN ≈ 31 K with an effective magnetic moment of μ = 2.68 μB corresponding to V3+. Low-field M(H) measurements revealed the existence of a small ferromagnetic component below TN in bulk TlV5Se8 and, despite the observed spin frustration, no spin glass phase was found in this compound. © 2015 The Royal Society of Chemistry.

A common method designed to identify if an animal hears tinnitus assumes that tinnitus “fills-in” silent gaps in background sound. This phenomenon has not been reliably demonstrated in humans. One test of the gap-filling hypothesis would be to determine if gap-evoked cortical potentials are absent or attenuated when measured within background sound matched to the tinnitus sensation. However the tinnitus sensation is usually of low intensity and of high frequency, and it is unknown if cortical responses can be measured with such “weak” stimulus properties. Therefore the aim of the present study was to test the plausibility of observing these responses in the EEG in humans without tinnitus. Twelve non-tinnitus participants heard narrowband noises centered at sound frequencies of 5 or 10 kHz at sensation levels of either 5, 15, or 30 dB. Silent gaps of 20 ms duration were randomly inserted into noise stimuli, and cortical potentials evoked by these gaps were measured by 64-channel EEG. Gap-evoked cortical responses were statistically identifiable in all conditions for all but one participant. Responses were not significantly different between noise frequencies or levels. Results suggest that cortical responses can be measured when evoked by gaps in sounds that mirror acoustic properties of tinnitus. This design can validate the animal model and be used as a tinnitus diagnosis test in humans.

Single-crystal and polycrystalline Ba

Les effets thermoelectriques permettent de transformer une difference de temperature ΔT en une difference de potentiel electrique ΔV via l’effet Seebeck, ou ΔV en ΔT via l’effet Peltier. Ces deux effets sont de bonnes sondes de la structure electronique des materiaux, et peuvent egalement etre utilises pour transformer la chaleur perdue en electricite (mode Seebeck) ou pour fabriquer des refroidisseurs (mode Peltier).Limitee pour le moment a des secteurs tres specialises comme le spatial, la thermo-electricite connait un regain d’interet depuis les annees 1990 – 2000, suite a differentes propositions visant a ameliorer les performances des materiaux thermoelectriques.

The strong interplay between magnetism and transport can tune the thermoelectric properties in chalcogenides and oxides. In the case of ferromagnetic CoS 2 pyrite, it was previously shown that the power factor is large at room temperature, reaching 1 mW m −1 K −2 and abruptly increases for temperatures below the Curie transition ( T C ), an increase potentially due to a magnonic effect on the Seebeck ( S ) coefficient. The too large thermal conductivity approximately equal to 10.5 W m −1 K −1 at room temperature prevents this pyrite from being a good thermoelectric material. In this work, samples belonging to the Co 1− x Fe x S 2 pyrite family ( x = 0, 0.15 and 0.30) have thus been investigated in order to modify the thermal properties by the introduction of disorder on the Co site. We show here that the thermal conductivity can indeed be reduced by such a substitution, but that this substitution predominantly induces a reduction of the electronic part of the thermal conductivity and not of the lattice part. Interestingly, the magnonic contribution to S below T C disappears as x increases, while at high T , S tends to a very similar value (close to −42 µV K −1 ) for all the samples investigated. This article is part of a discussion meeting issue ‘Energy materials for a low carbon future’.

The transport properties of TlxCr5Se8 pseudo-hollandite have been investigated, from 2 up to 800 K. A semiconducting behavior is observed from 200 down to 2 K, with a transition observed at T ∼ 43 K, at the antiferromagnetic transition. Above 200 K, small values of ρ are obtained, close to 10 mΩ·cm at 800 K. The Seebeck coefficient continuously increases in this range of temperature, reaching 300 μV/K at 800 K. Moreover, the thermal conductivity of this low dimensional structure is small, leading to a figure of merit ZT = S2T/(ρκ) = 0.5 at 800 K. All the electronic transport properties can be fitted by a standard Boltzmann equation, with a large scattering parameter (r = 3/2, characteristic of diffusion by ionized impurities). The combination of small thermal conductivity, large scattering parameter, and low concentration of carriers (4.5 × 1019 cm–3) is at the origin of this large ZT.

Current clinical assessment of tinnitus relies mainly on self-report. Psychoacoustic assessment of tinnitus pitch and loudness are recommended but methods yield variable results. Herein we investigated the proposition that a previously validated fixed laboratory-based method (Touchscreen) and a newly developed clinically-relevant portable prototype (Stand-alone) yield comparable results in the assessment of psychoacoustic tinnitus pitch and loudness. Participants with tinnitus (N=15, 7 with normal hearing and 8 with hearing loss) and participants simulating tinnitus (Simulators, N=15) were instructed to rate the likeness of pure tones (250 – 16 kHz) to their tinnitus pitch and match their loudness using both methods presented in a counterbalanced order. Results indicate that simulators rated their “tinnitus” at lower frequencies and at louder at louder levels (~ 10 dB) compared to tinnitus participants. Tinnitus subgroups (with vs. without hearing loss) differed in their predominant tinnitus pitch (i.e., lower in the tinnitus with hearing loss subgroups) but not in their loudness matching in dB SL. Loudness at the predominant pitch was identified as a factor yielding significant sensitivity and specificity in discriminating between the two groups of participants. Importantly, despite differences in the devices’ physical presentations, likeness and loudness ratings were globally consistent between the two methods and, moreover, highly reproducible from one method to the other in both groups. All in all, both methods yielded robust tinnitus data in less than 12 minutes, with the Stand-alone having the advantage of not being dependent of learning effects, being user-friendly, and being adapted to the audiogram of each patient to further reduce testing time.

International audience; Single-crystal and polycrystalline Ba4Cu8Se13 were synthesized; the average crystal structure was solved by single-crystal X-ray diffraction, and the structural model was confirmed by a detailed electron microscopy study of polycrystalline Ba4Cu8Se13. The title compound can be rationalized as (Ba2+)(4)(Cu+)(8)(Se2-)(2)(Se-2(2-))(4)(Se-3(4-)) and crystallizes in a new structure type (space group C2/c with a = 9.171(8) angstrom, b = 9.146(8) angstrom, c = 27.35 (3) angstrom, beta = 93.21(3)degrees, and V = 2291 angstrom(3). It contains unprecedented Cu4Se9 fragments with planar Cu rectangles. These fragments form two-dimensional layers via regular (2c-2e) Se-Se bonds. Two of these layers are then connected in the third dimension via linear, hypervalent Se-3(4-) units, resulting in "sandwichlike", layered building blocks, which are stacked along c and separated by Ba. Ba4Cu5Se13 is the first example-where Se-2(2-) and Se-3(4-) groups coexist. We were able to visualize the crystal structure by recording HAADF images, which clearly reveal the Cu4Se9 fragments and linear Se-3(4-) units. The title compound is a charge-balanced semiconductor and possesses a large Seebeck coefficient (380 mu V K-1 at 200 K) and a low thermal conductivity (0.77 W m(-1) K-1 at 200 K) two requirements for efficient thermoelectric materials.

This contribution highlights the role of stress-related psychological conditions in tinnitus. Relevant psychological disorders such as mood and anxiety disorders are introduced, and their relation with stress is presented. Further, the incidence of psychological disorders among patients with tinnitus is presented and the clinical and therapeutic implications suggested.