Effect of headphone position on absolute threshold measurements

International audiencePure-tone audiometry (measurement of absolute thresholds using pure tones) is the main test for the diagnosis of hearing loss. The aim of the present study is to determine whether the headphone placement over a listener’s ears has an influence on pure-tone audiometric tests, for a large frequency range, for Sennheiser HD600 and Telephonics TDH39 headphones. Audiograms (with 1 dB step, and including 10 frequencies up to 14 kHz) were performed several times on normal-hearing subjects, for different – or not different – headphone positions (allowing to dissociate between effects of headphone position and cognitive factors). Globally, the results seem to indicate that the reliability without headphone removing was quite close to the one observed with removing. The influence of removing did not appear more crucial for high frequencies. The rare frequencies for which a removing effect was seen seem to be function of the headphone model. Finally the results were quite different among the subjects

Influence of headphone position in pure-tone audiometry

International audiencePure-tone audiometry (measurement of absolute thresholds using pure tones) is the main test for the diagnosis of hearing loss. It can be achieved by using either air conduction (with headphones or loudspeakers) or bone conduction (by placing a vibrator on the mastoid bone behind the ear). The HeadPhone Transfer Function (HPTF) describes both the headphone response and the coupling to a listener's ear. Recent papers indicated that modifications of headphone position can lead to changes in HPTF, and that these spectral modifications can be audible. The aim of the present study is to determine whether the headphone placement over a listener's ears has an influence on pure-tone audiometric tests. Audiograms were performed several times on normal-hearing subjects, for different headphone positions (obtained by placing/removing the headphone over the listener's ears), the absolute thresholds measurements being repeated for each headphone position. The dispersions of absolute thresholds with and without modification of the headphone position were compared in order to determine whether the headphone positioning is an issue for audiometric tests

Microstructure evolution of gold thin films under spherical indentation for micro switches contact applications

RF MEMS (Radio Frequency Micro Electro Mechanical System) switches are promising devices but their gold-on-gold contacts, assimilated for this work to a sphere / plane contact, represent a major reliability issue. A first step towards failure mechanism understanding is the investigation of the contact metal microstructure evolution under static and cyclic loading. After static and cyclic loading of sputtered gold thin films under spherical indentation, high resolution Electron Back Scatter Diffraction (EBSD) is used to investigate contact area. Grain rotation against {111} fiber texture of 1 μm thick sputtered gold thin film is a signature of plastic deformation. Grain rotation is observed above 1.6 mN under static loading by a spherical diamond indenter with 50 μm tip radius. A heterogeneity in grain rotation is observed corresponding to a more important plastic deformation in the middle of the indent than at the edge. A 30° Grain rotation is observed for a half million mechanical cycles under 300 μN load by a spherical gold tip (20 μm radius) due to cyclic work hardening. The same test in hot switching mode induces a grain growth in the contact area. Therefore thermal effects occurring during hot switching are underline

The "SAPIN" Legislation and its Effects on Tendering and Competition in Public Transport in France

Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

Réduction des charges alimentaires des cobayes (Cavia porcellus L.) par un régime fourrager supplémenté par la farine de poisson et/ou du maïs-grain durant le cycle de reproduction

La supplémentation de Panicum maximum Jacq par l'aliment concentré granulé pour lapin a l'avantage d'induire une meilleure productivité des cobayes (Cavia porcellus L.) et a pour inconvénient d'être relativement coûteux. Afin de réduire le coût de production des cobayes, quatre régimes alimentaires que sont : Panicum maximum et Euphorbia heterophylla associé au maïs-grain (PEM), ou associé à la farine de poisson (PEF), ou associé au grain de maïs et à la farine de poisson (PEMF) et Panicum maximum associé au granulé pour lapin (PG; régime témoin), ont été distribués ad libitum à 24 cobayes femelles multipares durant la gestation et l’allaitement. Les valeurs moyennes du taux de fécondité, des poids à la naissance et des croissances journalières des cobayes au cours de la lactation ont été 83, 100, 167 et 200% ; 71±14, 88±18, 98±17 et 104±10 g ; et 5±1, 6±1, 7±1 et 8±1 g.j-1 respectivement pour PEM, PEF, PEMF et PG. Les résultats obtenus dans cette étude montrent que le régime constitué de Panicum maximum, Euphorbia heterophylla et de farine de poisson (PEF) semble être une solution optimale en milieu rural, avec une réduction de 55% des charges liées à l'alimentation en comparaison à PGMots clés : Cobaye, fourrage, Euphorbia heterophylla, Panicum maximum, farine de poisson, économie

Which drugs are best when aggressive Alzheimer's patients need medication?

Atypical antipsychotics are an effective short-term (6-12 weeks) treatment for aggressive behavior in patients with Alzheimer's disease because they consistently decrease aggression scores (strength of recommendation [SOR]: A, multiple randomized controlled trials [RCTs]). However, evidence of drug-related deaths in patients taking these drugs mandates weighing the benefits against the risks. SSRIs may be a safer, effective alternative (SOR: B, limited studies). Evidence for the efficacy of antiepileptic agents is conflicting (SOR: C, inconsistent patient-oriented evidence). Valproate is ineffective for treating aggression (SOR: C, very small RCT). No data exist to guide long-term medication use. All available studies lasted no longer than 12 weeks. Nonpharmacologic therapy should be the first-line treatment for aggression in patients with Alzheimer's disease. Consider drug therapy for patients who pose an imminent threat to themselves or others

Appetite Suppressants as Adjuncts for Weight Loss

Phentermine and diethylpropion are appetite suppressants approved for use in the United States as adjuncts in the treatment of obesity. These agents demonstrate a modest weight loss benefit when combined with dietary modifications and exercise. (Strength of Recommendation: B, based on a randomized trial and a meta-analysis.) No current evidence is available on the long-term risks and benefits of these medications, or the most appropriate time to initiate appetite suppressant therapy as part of a comprehensive weight management program

ADOLESCENTS IN TRANSITION TO YOUNG ADULTHOOD: EVOLUTION OF MENTAL HEALTH STATUS AND RISK FACTORS ASSOCIATED WITH DEPRESSIVE AND ANXIETY DISORDER

Background: In this paper we focus on adolescents in transition towards young adulthood (ATYA). We know from international studies that the transition process makes adolescents vulnerable to mental illness. However, little is known about Belgian ATYA mental-health status. Nor are risk factors associated with their mental illness understood, in particular with regard to depressive and anxiety disorder. The aim of this study is (1) to discuss evolution in time of prevalence of depressive disorder (DD) and anxiety disorder (AD) among Belgian ATYA and (2), to identify risk factors associated with these disorders among ATYA. Subjects and methods: Data was extracted from the Belgian Health Interview Survey (BHIS), which is a cross-sectional population survey, carried out in 2001, 2004, 2008, and 2013. Information about the population’s background characteristics, health services utilization, health behaviours and mental health status were extracted and statistically analyzed. Results: ATYA prevalence of DD and AD was higher in 2013 in comparison with previous years. These changes were significant only for DD (F=4.466, p=0.004). In contrast with younger adolescents, among ATYA odds of DD were 28.2% higher (OR 1.282, 95% CI 0.967-1.698, p=0.084) and, odds of AD were 55.2% higher (OR 1.552, 95% CI 1.137-2.119, p=0.006). For ATYA, a poor quality of social support was the most predictive factor of DD (OR 11.187, 95% CI 5.530-22.629, p<0.0001) and AD (OR 6.238, 95% CI 2.845-13.676, p<0.0001); whereas, having a paid job was the most protective factor with regard to DD (OR 0.282, 95% CI 0.169-0.470, p<0.0001) and AD (OR 0.552, 95% CI 0.330-0.924, p<0.024). Conclusion: Prevalence of mental illness among Belgian ATYA appears to worsen in time. In comparison with younger adolescents, ATYA are more vulnerable to anxiety disorders. Adverse and protective risk factors were identified and discussed in a way to improve access, continuity and mental healthcare pathways for Belgian ATYA

Quantification of mass transfers and mineralogical transformations in a thrust fault (Monte Perdido thrust unit, southern Pyrenees, Spain)

In fold-and-thrust belts, shortening is mainly accommodated by thrust faults which are preferential zones for recrystallisation and mass transfer. This study focuses on a detachment fault related to the emplacement of the Monte Perdido thrust unit in the southern Pyrenees. The studied fault zone consists of a 10 m thick intensively foliated phyllonite developed within the Millaris marls, of Eocene age. The lithological homogeneity of the hanging wall and footwall allows us to compare the Millaris marls outside the fault zone with the highly deformed marls located in the fault zone and to quantify the chemical, mineralogical and volumetric changes related to deformation processes along the fault. The Millaris marls are composed of detrital quartz, illite, chlorite, minor albite and pyrite, in a micritic calcite matrix. In the fault zone, the cleavage planes are marked by clay minerals and calcite ± chlorite veins attest to fluid–mineral interactions during deformation. The mineral proportions in all samples from both the fault zone and Millaris marls have been quantified by two methods: (1) X-ray diffraction and Rietveld refinement, and (2) bulk chemical analyses as well as microprobe analyses to calculate modal composition. The excellent agreement between the results of these two methods allows us to estimate mineralogical variations using a modification of the Gresens' equation. During fault activation, up to 45 wt% of calcite was lost while the amounts of quartz and chlorite remained unchanged. Illite content remained constant to slightly enriched. The mineralogical variations were coupled with a significant volume loss (up to 45%) mostly due to the dissolution of micritic calcite grains. Deformation was accompanied by pressure solution and phyllosilicates recrystallisation. These processes accommodated slip along the fault. They required fluids as catalyst, but they did not necessitate major chemical transfers