1,593 research outputs found

    Critical Repetition Rates for Perceptual Segregation of Time-Varying Auditory, Visual and Vibrotactile Stimulation

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    What sound quality has led to exclude infrasound from sound in the conventional hearing range? We examined whether temporal segregation of pressure pulses is a distinctive property and evaluated this perceptual limit via an adaptive psychophysical procedure for pure tones and carriers of different envelopes. Further, to examine across-domain similarity and individual covariation of this limit, here called the critical segregation rate (CSR), it was also measured for various periodic visual and vibrotactile stimuli. Results showed that sequential auditory or vibrotactile stimuli separated by at least ~80‒90 ms (~11‒12-Hz repetition rates), will be perceived as perceptually segregated from one another. While this limit did not statistically differ between these two modalities, it was significantly lower than the ~150 ms necessary to perceptually segregate successive visual stimuli. For the three sensory modalities, stimulus periodicity was the main factor determining the CSR, which apparently reflects neural recovery times of the different sensory systems. Among all experimental conditions, significant within- and across-modality individual CSR correlations were observed, despite the visual CSR (mean: 6.8 Hz) being significantly lower than that of both other modalities. The auditory CSR was found to be significantly lower than the frequency above which sinusoids start to elicit a tonal quality (19 Hz; recently published for the same subjects). Returning to our initial question, the latter suggests that the cessation of tonal quality — not the segregation of pressure fluctuations — is the perceptual quality that has led to exclude infrasound (sound with frequencies < 20 Hz) from the conventional hearing range

    Scissors resonance in the quasi-continuum of Th, Pa and U isotopes

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    The gamma-ray strength function in the quasi-continuum has been measured for 231-233Th, 232,233Pa and 237-239U using the Oslo method. All eight nuclei show a pronounced increase in gamma strength at omega_SR approx 2.4 MeV, which is interpreted as the low-energy M1 scissors resonance (SR). The total strength is found to be B_SR = 9-11 mu_N^2 when integrated over the 1 - 4 MeV gamma-energy region. The SR displays a double-hump structure that is theoretically not understood. Our results are compared with data from (gamma, gamma') experiments and theoretical sum-rule estimates for a nuclear rigid-body moment of inertia.Comment: 11 pages, 9 figure

    Phylogenetic analyses and toxigenic profiles of Fusarium equiseti and Fusarium acuminatum isolated from cereals from Southern Europe

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    Fusarium equiseti and Fusarium acuminatum are toxigenic species that contaminate cereal crops from diverse climatic regions. They are common in Spanish cereals. The information available on their phylogenetics and toxigenic profiles is, however, insufficient to assist risk evaluation. In this work, phylogenetic analyses were performed using partial sequences of the translation elongation factor gene (EF-1a) of F. equiseti and F. acuminatum strains isolated from barley and wheat from Spain and other countries. The Northern and Southern European F. equiseti strains largely separated into two phylogenetically distinct clusters. This suggests the existence of two distinct populations within this species, explaining its presence in these regions of markedly different climate. Production of type A and B trichothecenes by the Spanish strains, examined in wheat cultures using a multitoxin analytical method, indicated that F. equiseti could produce deoxynivalenol and nivalenol and other trichothecenes, at concentrations that might represent a significant risk of toxin contamination for Southern European cereals. F. acuminatum showed low intraspecific genetic variability and 58% of the strains could produce deoxynivalenol at low level. Neither species was found to produce T-2 or HT-2 toxins. The present results provide important phylogenetic and toxigenic information essential for the accurate prediction of toxigenic risk

    Perceived quality of life and the specific physical activities by the elderly

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    Se analizaron indicadores de salud con respecto a la percepción de la calidad de vida (CVRS) mediante el cuestionario Short Form-36 Health Survey (SF-36) y parámetros cinemáticos manifestados en el movimiento press banca (12 kilos) como predictores de las adaptaciones neurofisiológicas que se producen con la actividad física. Se trataron valores de potencia, de velocidad, aceleraciones, fuerza y variables temporales. Se utilizaron dos grupos, uno activo, de práctica física habitual (12H, 6M, 68,4±5,6 años, 1,65±0,074m, 74,57±15,41kg, BMI 26,93±4,02; act/sem 4,5±1,65h.), y otro sedentario (16H, 7M, 69 ± 7,07 años, 1,67 ± 0,072m, 74,95 ± 7,4kg, BMI 26,84±2,78) Se encontraron diferencias significativas (p<0,05;gl=1,39;dz=0,5). El grupo considerado activo se percibe con mejor calidad de vida y manifiesta de manera más rápida y con mayor fuerza el movimiento solicitado. Las conclusiones son relevantes para posteriores estudios que se centren en la pérdida de propiedades neuromusculares acompañada a la falta de práctica y al efecto del envejecimiento.Quality of life related to health indicators (QLRH) were analyzed by means of the Short Form-36 Health Survey (SF-36) questionnaire and the specified kinetic parameters of the bench press movement (12 kg) as predictors of the neurophysiological adaptations produced by physical activity. These were the values of power, velocity, acceleration, strength and temporal variables. Two groups were studied: the first group was active, undertaking regular physical activity (12 male; 6 female; 68,4±5,6 years; 1,65±0,074m; 74,57±15,41kg; BMI 26,93±4,02; weekly activity 4,5±1,65h.); the second group was sedentary (16 male; 7 female; 69±7,07 years; 1,67±0,072m; 74,95±7,4kg; BMI 26,84±2,78). Significant differences were found (p<0,05;df=1,39;dz=0,5). The group regarded as active considered itself as having a better quality of life and was able to perform the requested movement with greater speed and strength. The conclusions are relevant for future studies that centre on the loss of neuromuscular properties accompanied by a lack of physical activity and the effects of aging

    Predictive value of hyperglycosylated human chorionic gonadotropin for pregnancy outcomes in threatened abortion in first-trimester viable pregnancies

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    Background. To investigate the value of a single determination of hyperglycosylated hCG (hCG-H) for predicting the clinical outcome of patients with threatened abortion in the first trimester of pregnancy. Methods. Prospective study performed on 86 consecutively selected women with a diagnosis of threatened abortion and viable intrauterine pregnancy in the first trimester of pregnancy, conducted in two tertiary care hospitals. All patients underwent a single blood sample to determine hCG-H and total hCG serum levels and a transvaginal ultrasound 12-24 hours after diagnosis. Patients were monitored to determine whether the outcome was a miscarriage before the 20th week of pregnancy. Results. Forty-three women (50%) had a miscarriage during the follow-up. We observed a very high correlation between hCG-H and total hCG (r=0.91, p<0.001). Median hCG-H and total hCG from pregnancies with normal outcome was significantly higher than those ending in abortion. hCG-H and total hCG were very similar predictors of pregnancy outcomes (AUC: 0.90 and 0.89, respectively). The ratio hCG-H / total hCG was a poor predictor (AUC:0.64). Conclusion. A single hCG-H assay is helpful for predicting pregnancy outcomes in women with first trimester threatened abortion and viable or potentially viable pregnancy at the time of presentation. However, hCG-H is not a better predictor than total hCG.Fundamento. Investigar el valor de una única determinación de hCG hiperglicosilada (hCG-H) para predecir el resultado clínico de pacientes con amenaza de aborto en el primer trimestre del embarazo. Métodos. Estudio prospectivo realizado en 86 mujeres, seleccionadas consecutivamente, con diagnóstico de amenaza de aborto y embarazo intrauterino viable en el primer trimestre de embarazo, realizado en dos hospitales de tercer nivel. A todas las pacientes se les realizó una única extracción sanguínea para determinar los niveles séricos de hCG-H y hCG total, y una ecografía transvaginal 12-24 horas después del episodio de sangrado. Se realizó seguimiento de las pacientes para determinar si el resultado fue un aborto espontáneo antes de la semana 20 de embarazo. Resultados. Cuarenta y tres mujeres (50%) sufrieron un aborto espontáneo durante el seguimiento. Se observó una correlación muy alta entre hCG-H y hCG total (r=0,91,p<0,001). La mediana de hCG-H y hCG total de los embarazos con resultado normal fue significativamente mayor que la de aquellos que terminaron en aborto. La hCG-H y la hCG total fueron predictores muy similares del resultado del embarazo (AUC: 0,90 y 0,89, respectivamente). La relación hCG-H / hCG total fue un mal predictor (AUC:0,64). Conclusión. La determinación única de hCG-H es útil para predecir el resultado del embarazo en mujeres con amenaza de aborto en el primer trimestre y embarazo viable en el momento de la presentación clínica. Sin embargo, la hCG-H no es mejor predictor que la hCG total

    Approaching the Gamow Window with Stored Ions : Direct Measurement of Xe 124 (p,γ) in the ESR Storage Ring

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    © 2019 American Physical Society. All rights reserved.We report the first measurement of low-energy proton-capture cross sections of Xe124 in a heavy-ion storage ring. Xe12454+ ions of five different beam energies between 5.5 and 8 AMeV were stored to collide with a windowless hydrogen target. The Cs125 reaction products were directly detected. The interaction energies are located on the high energy tail of the Gamow window for hot, explosive scenarios such as supernovae and x-ray binaries. The results serve as an important test of predicted astrophysical reaction rates in this mass range. Good agreement in the prediction of the astrophysically important proton width at low energy is found, with only a 30% difference between measurement and theory. Larger deviations are found above the neutron emission threshold, where also neutron and γ widths significantly impact the cross sections. The newly established experimental method is a very powerful tool to investigate nuclear reactions on rare ion beams at low center-of-mass energies.Peer reviewedFinal Published versio

    Detection of Aruco Markers Using the Quadrilateral Sum Conjuncture

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    Fiducial Markers are heavily used for pose estimation in many applications from robotics to augmented reality. In this paper we present an algorithm for the detection of aruco marker at larger distance. The algorithm uses the quadrilateral sum conjecture and analyzes the sum of the cosine of the internal angles to detect squares at larger distances. Experiments conducted showed that the developed solution was able to improve the detection distance when compared to other methods that use similar marker while keeping similar pose estimation precision.publishe

    MIPAS temperature from the stratosphere to the lower thermosphere: Comparison of vM21 with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and lidar measurements

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    We present vM21 MIPAS temperatures from the lower stratosphere to the lower thermosphere, which cover all optimized resolution measurements performed by MIPAS in the middle-atmosphere, upper-atmosphere and noctilucent-cloud modes during its lifetime, i.e., from January 2005 to April 2012. The main upgrades with respect to the previous version of MIPAS temperatures (vM11) are the update of the spectroscopic database, the use of a different climatology of atomic oxygen and carbon dioxide, and the improvement in important technical aspects of the retrieval setup (temperature gradient along the line of sight and offset regularizations, apodization accuracy). Additionally, an updated version of ESA-calibrated L1b spectra (5.02/5.06) is used. The vM21 temperatures correct the main systematic errors of the previous version because they provide on average a 1–2 K warmer stratopause and middle mesosphere, and a 6–10 K colder mesopause (except in high-latitude summers) and lower thermosphere. These lead to a remarkable improvement in MIPAS comparisons with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and the two Rayleigh lidars at Mauna Loa and Table Mountain, which, with a few specific exceptions, typically exhibit differences smaller than 1 K below 50 km and than 2 K at 50–80 km in spring, autumn and winter at all latitudes, and summer at low to midlatitudes. Differences in the high-latitude summers are typically smaller than 1 K below 50 km, smaller than 2 K at 50–65 km and 5 K at 65–80 km. Differences between MIPAS and the other instruments in the mid-mesosphere are generally negative. MIPAS mesopause is within 4 K of the other instruments measurements, except in the high-latitude summers, when it is within 5–10 K, being warmer there than SABER, MLS and OSIRIS and colder than ACE-FTS and SOFIE. The agreement in the lower thermosphere is typically better than 5 K, except for high latitudes during spring and summer, when MIPAS usually exhibits larger vertical gradients

    Evaporation residues produced in spallation of 208Pb by protons at 500A MeV

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    The production cross sections of fragmentation-evaporation residues in the reaction Pb+p at 500A MeV have been measured using the inverse-kinematics method and the FRS spectrometer (GSI). Fragments were identified in nuclear charge using ionisation chambers. The mass identification was performed event-by-event using the B-rho - TOF - Delta-E technique. Although partially-unresolved ionic charge states induced an ambiguity on the mass of some heavy fragments, production rates could be obtained with a high accuracy by systematically accounting for the polluting ionic charge states. The contribution of multiple reactions in the target was subtracted using a new, partly self-consistent code. The isobaric distributions are found to have a shape very close to the one observed in experiments at higher energy. Kinematic properties of the fragments were also measured. The total and the isotopic cross sections, including charge-pickup cross sections, are in good agreement with previous measurements. The data are discussed in the light of previous spallation measurements, especially on lead at 1 GeV
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