47 research outputs found
Parameterized maximum likelihood method (PML): application to space-time radar localization
We present a maximum likelihood method for the localization of sources with known waveforms . It's a joint space time
radar localization which is a generalisation of recent methods to coherent signal . The obtained results are usefull in wireless
communications for the identification of propagation channel with a pilot signal . An exact maximum likelihood method is presented .
Variances of estimation and related Cramer Rao Bound are established . Simulations results illustrate the behaviour of the algorithm.Nous prĂ©sentons une technique du maximum de vraisemblance qui localise des sources dont les formes d'ondes sont identiques et connues. Il s'agit d'une localisation radar conjointe direction-retard qui est une extension aux cas de signaux cohĂ©rents des mĂ©thodes actuellement utilisĂ©es et exploitant la connaissance des signaux Ă©mis. Les rĂ©sultats obtenus s'appliquent de la mĂȘme maniĂšre aux cas des communications mobiles pour lesquelles on veut identifier le canal de propagation Ă l'aide d'un signal connu. Un estimateur exact du maximum de vraisemblance est prĂ©sentĂ©. Les variances d'estimation ainsi que les bornes de Cramer-Rao sont Ă©tablies. Des rĂ©sultats de simulations viennent illustrer le comportement des algorithmes pour lesquels les performances sont comparĂ©es Ă la borne de Cramer-Rao
Resveratrol inhibits nonalcoholic fatty liver disease in rats
<p>Abstract</p> <p>Background</p> <p>The prevalence of nonalcoholic fatty liver disease (NAFLD) is high. NAFLD is linked to obesity, diabetes mellitus, and hypertriglyceridemia. Approximately 20% of patients with NAFLD will eventually develop cirrhosis. Our purpose was to investigate whether resveratrol decreased hepatic steatosis in an animal model of steatosis, and whether this therapeutic approach resulted in a decrease in tumor necrosis factor α (TNF-α) production, lipid peroxidation and oxidative stress.</p> <p>Methods</p> <p>Male Wistar CRL: Wi (Han) (225 g) rats were randomized into three groups. A control group (n = 12) was given free access to regular dry rat chow for 4 weeks. The steatosis (n = 12) and resveratrol (n = 12) groups were given free access to feed (a high carbohydrate-fat free modified diet) and water 4 days per week, and fasted for the remaining 3 days for 4 weeks. Rats in the resveratrol group were given resveratrol 10 mg daily by the oral route. All rats were killed at 4 weeks and assessed for fatty infiltration and bacterial translocation. Levels of TNF-α in serum, hepatic malondialdehyde (MDA), oxidative stress (superoxide dismutase, glutathione peroxidase, catalase and nitric oxide synthase) and biochemical parameters were measured.</p> <p>Results</p> <p>Fat deposition was decreased in the resveratrol group as compared to the steatosis group (Grade 1 vs Grade 3, P < 0.05). TNF-α and MDA levels were significantly increased in the steatosis group (TNF-α; 33.4 ± 5.2 vs 26.24 ± 3.47 pg/ml and MDA; 9.08 ± 0.8 vs 3.17 ± 1.45 ΌM respectively, <it>P </it>< 0.05). This was accompanied by increased superoxide dismutase, glutathione peroxidase and catalase and decreased nitric oxide synthase in the liver of resveratrol group significantly (<it>P </it>< 0.05 vs steatosis group). Bacterial translocation was not found in any of the groups. Glucose levels were decreased in the group of rats given resveratrol (<it>P </it>< 0.05).</p> <p>Conclusion</p> <p>Resveratrol decreased NAFLD severity in rats. This effect was mediated, at least in part, by TNF-α inhibition and antioxidant activities.</p
Structure of Dark Triad Dirty Dozen Across Eight World Regions
The Dark Triad (i.e., narcissism, psychopathy, Machiavellianism) has garnered intense attention over the past 15 years. We examined the structure of these traitsâ measureâthe Dark Triad Dirty Dozen (DTDD)âin a sample of 11,488 participants from three W.E.I.R.D. (i.e., North America, Oceania, Western Europe) and five non-W.E.I.R.D. (i.e., Asia, Middle East, non-Western Europe, South America, sub-Saharan Africa) world regions. The results confirmed the measurement invariance of the DTDD across participantsâ sex in all world regions, with men scoring higher than women on all traits (except for psychopathy in Asia, where the difference was not significant). We found evidence for metric (and partial scalar) measurement invariance within and between W.E.I.R.D. and non-W.E.I.R.D. world regions. The results generally support the structure of the DTDD
Data for: Extremely long-term memory and familiarity after 12 years
## RESULTS
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Task1: Forced-choice for TEST participants: filename: classeur'x'_set'y'Choix_forcé_pp_'z'_TESTMarseille.xlsx
Forced-choice for CONTROL participants: filename: classeur'x'_set'y'Choix_forcé_pp_'z'_CTRL.xlsx
Task2: Yes/No for TEST participants: filename: Oui_Non_pp'z'_TESTMarseille.xlsx
## MATERIAL
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# BINDERS
A binder was used for each participant including three different sets.
Power point file of the binders: classeur'x'_set'y'.pptx
# STIMULI
PNG file starting by "C_": stimuli seen at least 3 times in the initial DMS-48
PNG file starting by "D1_": stimuli seen once in the initial DMS-48 during the first recognition test performed 3 min after the incidental encoding
PNG file starting by "D2_": stimuli seen once in the initial DMS-48 during the second recognition test performed 1h after the incidental encoding
PNG file starting by "LC_", "LD1_" and "LD2_" : the lures of the respective stimuli that are found in the precedent folders
Application of model-based spectral analysis to wind-profiler radar observations
International audienceA classical way to reduce a radar's data is to compute the spectrum using FFT and then to identify the different peak contributions. But in case an overlapping between the different echoes (atmospheric echo, clutter, hydrometeor echo. . . ) exists, Fourier-like techniques provide poor frequency resolution and then sophisticated peak-identification may not be able to detect the different echoes. In order to improve the number of reduced data and their quality relative to Fourier spectrum analysis, three different methods are presented in this paper and applied to actual data. Their approach consists of predicting the main frequency-components, which avoids the development of very sophisticated peak-identification algorithms. The first method is based on cepstrum properties generally used to determine the shift between two close identical echoes. We will see in this paper that this method cannot provide a better estimate than Fourier-like techniques in an operational use. The second method consists of an autoregressive estimation of the spectrum. Since the tests were promising, this method was applied to reduce the radar data obtained during two thunder-storms. The autoregressive method, which is very simple to implement, improved the Doppler-frequency data reduction relative to the FFT spectrum analysis. The third method exploits a MUSIC algorithm, one of the numerous subspace-based methods, which is well adapted to estimate spectra composed of pure lines. A statistical study of performances of this method is presented, and points out the very good resolution of this estimator in comparison with Fourier-like techniques. Application to actual data confirms the good qualities of this estimator for reducing radar's data
Rheological monitoring of tau protein polymerisation with acoustic waves sensor
International audienceAmong acoustic waves sensors, the thickness shear mode resonator presents high sensitivity for the measurement of liquid viscoelastic properties, enabling the monitoring of the shear moduli, GâČ Gâł, by using a suitable physical model. The development of an instrumental system for detecting the tau protein involved in Alzheimer's disease is proposed which will aid in understanding the mechanisms of this disease. The tau protein is present in complex products such as blood and cerebrospinal fluid. The experimental results show that the acoustic wave system allows to differentiate between tau protein solutions with different states of polymerisation
CaracterizaciĂłn de cepas de Escherichia coli O157 no productoras de toxina Shiga aisladas de perros
Fil: Bentancor, Adriana. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. MicrobiologĂa; Argentina.Fil: Vilte, D. A. Instituto Nacional de TecnologĂa Agropecuaria. Instituto de BiotecnologĂa. Instituto de PatobiologĂa; Argentina.Fil: Moje Rumi, MarĂa. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. MicrobiologĂa; Argentina.Fil: Carbonari, Carolina C. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Servicio de Fisiopatogenia; Argentina.Fil: Chinen, Isabel. ANLIS Dr.C.G.MalbrĂĄn. Instituto Nacional de Enfermedades Infecciosas. Servicio de Fisiopatogenia; Argentina.Fil: Larzabal, M. Instituto Nacional de TecnologĂa Agropecuaria. Instituto de BiotecnologĂa. Instituto de PatobiologĂa; Argentina.Fil: Cataldi, A. Instituto Nacional de TecnologĂa Agropecuaria. Instituto de BiotecnologĂa. Instituto de PatobiologĂa; Argentina.Fil: Mercado, E. C. Instituto Nacional de TecnologĂa Agropecuaria. Instituto de BiotecnologĂa. Instituto de PatobiologĂa; Argentina.Shiga toxin-negative Escherichia coli O157 strains of various H types have been associated with diarrhea in children and are considered potentially pathogenic for humans. In this study, we describe non-Shiga toxin-producing E. coli O157 E. coli strains previously obtained from dogs in Argentina. Different E. coli phylogenetic lineages corresponding to flagellar types H16, H29 and H45 were identified. E. coli serotypes O157:H16 and O157:H45 contained intimin subtypes e and a1, respectively. Serotype O157:H45 carried the bfp gene encoding the bundle-forming pilus. Localized adherence-like patterns to HEp-2 cells were observed in O157:H16 strains, while O157:H45 adhered in a typical localized pattern. A total of eight different XbaI-pulse field electrophoresis patterns with more than 74 % similarity were identified among the nine E. coli O157:H16 strains. Our data emphasized the fact that dogs may harbor human pathogenic E. coli O157 which do not correspond to Shiga toxin-producing strains and whose potential human health hazard should not be underestimated