Subjective equivalence of steering wheel vibration and sound

The subjective equivalence between steering wheel vibration and sound was investigated in two experiments. In each experiment, 20 subjects were presented 64 pairs of simultaneous sound and vibration stimuli in a simulator which reproduced a realistic driving posture. The first used stimuli measured in an automobile when driving over a coarse asphalt road surface, while the second used data obtained by driving over a 1.0 cm square metal bar. In both experiments, the acceleration time histories were scaled to eight root mean square (r.m.s.) levels from 0.5 to 4.0 m/s2 and the sound pressure time histories were scaled to eight levels from 85 to 106 dB sound pressure level (SPL). Test subjects were asked to indicate which stimuli, the sound or the vibration, was felt to be the “more unpleasant”. Regression expressions of subjective equivalence were developed for both stimuli types, in both the unweighted (decibel versus r.m.s. acceleration) and the frequency-weighted (decibel(A) versus VDV) forms. Regression slopes were found to be in the range from 23.8 to 26.8, similar to values for whole-body vibration exposures. Subjective equivalence was, however, found to be 5–15 dB(A) lower for the coarse asphalt stimuli and 15–25 dB(A) lower for the square metal bar stimuli. All other conditions remain equal, the human response to the vibration was found to increase in relative importance with respect to the sound in the case of short duration, transient, square metal bar stimuli

Structural and properties of Zn-Al2O3-SiC nano-composite coatings by direct electrolytic process

In this paper, Zn-SiC and Zn-Al2O3-SiC composite coating were fabricated by electrodeposition technique from sulfates bath. The resulting composite coating was carried out by adding Al2O3/SiC particulate to a zinc-containing bath. The properties of the composite coating were investigated by SEM equipped with EDS, XRD, and AFM. The electrochemical behavior of the coating alloy was evaluated in 3.65 % NaCl with linear polarization technique and mechanically examined by durascan microhardness tester. The morphology of the thermal treated coatings at 400 °C in 6 h was viewed with high optical microscope (OPM). The results show hardness, thermal stability, and anti-corrosion properties of Zn-Al2O3-SiC were improved significantly as against Zn- SiC coating matrixes. This was attributed to dispersive strengthening effect and grain induced effort of Al2O3/SiC particulate. The decrease in corrosion and thermal stability at 15 g/L of SiC concentration may be as a result of agglomeration and the superimposed particle in the plating bath

<i>Gaia</i> Data Release 1. Summary of the astrometric, photometric, and survey properties

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release. Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue. Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues – a realisation of the Tycho-Gaia Astrometric Solution (TGAS) – and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of ∼3000 Cepheid and RR-Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr−1 for the proper motions. A systematic component of ∼0.3 mas should be added to the parallax uncertainties. For the subset of ∼94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr−1. For the secondary astrometric data set, the typical uncertainty of the positions is ∼10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to ∼0.03 mag over the magnitude range 5 to 20.7. Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data

A systematic review of clinical trials of pharmacological interventions for acute ischaemic stroke (1955-2008) that were completed, but not published in full

<p>Abstract</p> <p>Background</p> <p>We assessed the prevalence, and potential impact of, trials of pharmacological agents for acute stroke that were completed but not published in full. Failure to publish trial data is to be deprecated as it sets aside the altruism of participants' consent to be exposed to the risks of experimental interventions, potentially biases the assessment of the effects of therapies, and may lead to premature discontinuation of research into promising treatments.</p> <p>Methods</p> <p>We searched the Cochrane Stroke Group's Specialised Register of Trials in June 2008 for completed trials of pharmacological interventions for acute ischaemic stroke, and searched MEDLINE and EMBASE (January 2007 - March 2009) for references to recent full publications. We assessed trial completion status from trial reports, online trials registers and correspondence with experts.</p> <p>Results</p> <p>We identified 940 trials. Of these, 125 (19.6%, 95% confidence interval 16.5-22.6) were completed but not published in full by the point prevalence date. They included 16,058 participants (16 trials had over 300 participants each) and tested 89 different interventions. Twenty-two trials with a total of 4,251 participants reported the number of deaths. In these trials, 636/4251 (15.0%) died.</p> <p>Conclusions</p> <p>Our data suggest that, at the point prevalence date, a substantial body of evidence that was of relevance both to clinical practice in acute stroke and future research in the field was not published in full. Over 16,000 patients had given informed consent and were exposed to the risks of therapy. Responsibility for non-publication lies with investigators, but pharmaceutical companies, research ethics committees, journals and governments can all encourage the timely publication of trial data.</p

Gaia Data Release 1: Testing parallaxes with local Cepheids and RR Lyrae stars

Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims. In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, which involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity (M V -[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS. Methods. Classical Cepheids were carefully selected in order to discard known or suspected binary systems. The final sample comprises 102 fundamental mode pulsators with periods ranging from 1.68 to 51.66 days (of which 33 with σ Ω /Ω < 0.5). The Type II Cepheids include a total of 26 W Virginis and BL Herculis stars spanning the period range from 1.16 to 30.00 days (of which only 7 with σ Ω /Ω < 0.5). The RR Lyrae stars include 200 sources with pulsation period ranging from 0.27 to 0.80 days (of which 112 with σ Ω /Ω < 0.5). The new relations were computed using multi-band (V,I,J,K s ) photometry and spectroscopic metal abundances available in the literature, and by applying three alternative approaches: (i) linear least-squares fitting of the absolute magnitudes inferred from direct transformation of the TGAS parallaxes; (ii) adopting astrometry-based luminosities; and (iii) using a Bayesian fitting approach. The last two methods work in parallax space where parallaxes are used directly, thus maintaining symmetrical errors and allowing negative parallaxes to be used. The TGAS-based PL,PW,PLZ, and M V - [Fe/H] relations are discussed by comparing the distance to the Large Magellanic Cloud provided by different types of pulsating stars and alternative fitting methods. Results. Good agreement is found from direct comparison of the parallaxes of RR Lyrae stars for which both TGAS and HST measurements are available. Similarly, very good agreement is found between the TGAS values and the parallaxes inferred from the absolute magnitudes of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink method. TGAS values also compare favourably with the parallaxes inferred by theoretical model fitting of the multi-band light curves for two of the three classical Cepheids and one RR Lyrae star, which were analysed with this technique in our samples. The K-band PL relations show the significant improvement of the TGAS parallaxes for Cepheids and RR Lyrae stars with respect to the Hipparcos measurements. This is particularly true for the RR Lyrae stars for which improvement in quality and statistics is impressive. Conclusions. TGAS parallaxes bring a significant added value to the previous Hipparcos estimates. The relations presented in this paper represent the first Gaia-calibrated relations and form a work-in-progress milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia Data Release 2 (DR2) in 2018. © ESO, 2017

Gaia Data Release 1: Open cluster astrometry: performance, limitations, and future prospects

Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric Solution (TGAS). This is a subset of about 2 million stars for which, besides the position and photometry, the proper motion and parallax are calculated using Hipparcos and Tycho-2 positions in 1991.25 as prior information.Aims. We investigate the scientific potential and limitations of the TGAS component by means of the astrometric data for open clusters.Methods. Mean cluster parallax and proper motion values are derived taking into account the error correlations within the astrometric solutions for individual stars, an estimate of the internal velocity dispersion in the cluster, and, where relevant, the effects of the depth of the cluster along the line of sight. Internal consistency of the TGAS data is assessed.Results. Values given for standard uncertainties are still inaccurate and may lead to unrealistic unit-weight standard deviations of least squares solutions for cluster parameters. Reconstructed mean cluster parallax and proper motion values are generally in very good agreement with earlier HIPPARCOS-based determination, although the Gaia mean parallax for the Pleiades is a significant exception. We have no current explanation for that discrepancy. Most clusters are observed to extend to nearly 15 pc from the cluster centre, and it will be up to future Gaia releases to establish whether those potential cluster-member stars are still dynamically bound to the clusters.Conclusions. The Gaia DR1 provides the means to examine open clusters far beyond their more easily visible cores, and can provide membership assessments based on proper motions and parallaxes. A combined HR diagram shows the same features as observed before using the HIPPARCOS data, with clearly increased luminosities for older A and F dwarfs

The Gaia mission

Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page. http://www.cosmos.esa.int/gai

Epilepsia do lobo temporal: Relato de um paciente intacto após 26 anos de evolução sem tratamento Temporal lobe epilepsy: report of an intact patient 26 years after onset, without treatment

Apresentamos o caso de um paciente de 36 anos de idade com quadro clínico de epilepsia do lobo temporal, com crises tônico-clônicas desde os 10 anos de idade e parciais complexas desde os 30 anos, que nunca havia recebido tratamento. O diagnóstico foi feito clinicamente e com apoio do eletrencefalograma. A tomografia computadorizada de crânio foi normal. Foi realizado estudo das funções cognitivas com métodos validados em população de pacientes com epilepsia, da mesma origem social e geográfica que o paciente; os resultados foram semelhantes aos obtidos para a população de controle. O paciente também não mostrava alterações aos exames clínico geral, neurológico e das funções mentais. Ele tinha desempenho normal na sociedade, com estrutura familiar estável composta de esposa e filhos, e com emprego estável.<br>We present the case of a 36 years old man with temporal lobe epilepsy since 10 years old without treatment, and daily complex partial seizures and weekly tonic-clonic seizures. The diagnosis was made by clinical aspects and electroencephalographic findings. CT scan was normal. Cognitive functions were tested and showed no alterations. The patient had normal clinic, neurologic and mental exam

The Wada test with propofol in a patient with epilepsy Teste de Wada com propofol em uma paciente com epilepsia

The usual drug used in the Wada test is amobarbital, but it is not available in Brazil. Propofol was already used by Bazin et al. in 1998, and in their report the test resulted good in the absence of any adverse effect. We report the use of propofol as the anesthetic for the Wada test. The test was carried out in a 26 years old woman with temporal medial lobe epilepsy refractory to medical treatment. Language functions and memory were tested after injection in both hemispheres by three procedures (Seattle, Montreal and Interview procedures). Propofol showed to be good to carry on the Wada test.<br>O amobarbital é a droga usada no teste de Wada, mas não é disponível em nosso pais. O propofol, usado por Bazin et al. em 1998, foi útil e sem efeitos adversos. Relatamos o uso do propofol como anestésico no teste de Wada. Este foi realizado como parte da avaliação pre-cirúrgica, em uma mulher de 26 anos com epilepsia do lobo temporal mesial, em uso de carbamazepina e ácido valpróico sem controle de suas crises. As funções da linguagem e memória foram testadas após injeção em ambos hemisférios separadamente por três procedimentos (Seattle, Montreal e Entrevista). O propofol mostrou-se eficaz para a realização do teste de Wada