Analyses spectroscopiques du liquide céphalo-rachidien de rat en ex vivo et du noyau du raphé dorsal in vivo

Les propriétés d'absorption et de fluorescence du liquide céphalo-rachidien (LCR) ponctionné au niveau de la cisterna magna du rat, sont analysées puis comparées à l'émission mesurée in situ dans le noyau du raphe dorsal du rat libre de tous mouvements. Les mesures de fluorescence en ex vivo du LCR et in vivo du noyau raphé dorsal, ont été réalisées par la mise en œuvre d'un microcapteur à fibre optique (FOCS). La fluorescence mesurée in vivo sous excitation à 337 nm, présente 2 pics d'émission situés vers 410 et 460 nm. Les spectres d'absorption, d'émission en fluorescence statique et en fluorescence induite par laser sont rapportés. Avec des domaines de longueur d'onde d'excitation de 300-315 nm, 320-355 nm et 360-470 nm, les spectres d'émission du LCR en ex vivo montrent respectivement des pics centrés vers 340 nm, 390 nm et 530 nm. Malgré les limites liées aux différences de localisation anatomique, ces approches ainsi que celles de la littérature permettent de suggérer que le signal de fluorescence mesuré in vivo à 460nm pourrait dépendre pour une grande partie du NADH intracellulaire

Effects of diet supplementation with clove and rosemary essential oils and protected oils (eugenol, thymol and vanillin) on animal performance, carcass characteristics, digestibility, and ingestive behavior activities for Nellore heifers finished in feedlot

This study was carried out to evaluate the influence of essential oils and their blends on animal performance, feed intake, in situ digestibility, ingestive behavior activities, and carcass characteristics for heifers finished in feedlot on a high-grain diet (~65% corn, 25% corn silage, 10% soybean meal). Forty Nellore heifers (initial body weight 297.6 ± 31.2 kg) were used in the experiment and distributed randomly among individual pens. Dietary treatments based on essential oil additives included: CON – Without essential oil; ROS – Rosemary essential oil; BLE – Protected blend of eugenol, thymol, and vanillin; BCL – Protected blend + clove essential oil; and BRC – Protected blend + rosemary essential oil + clove essential oil. There were no diet effects on initial and final body weights. However, average daily gains, dry matter intakes (kg/d), and dry matter intakes (%BW) were greater (P < 0.05) in heifers fed with BLE, BCL, and BRC diets than in heifers fed with ROS diets. Feed efficiency (gain to feed) was greater (P < 0.0001) in heifers fed the BCL and BRC diets when compared to heifers fed the ROS diet. There were no diet effects on carcass characteristics. In situ digestibility of dry matter and neutral detergent fiber were greater (P < 0.0001) in heifers fed the three blended diets when compared to heifers fed the ROS diet. The addition of essential oils to the diets of heifers did not alter the muscle, fat, or bone percentages in the carcass. For ingestive behavior activities, data on rumination and idleness tended to be altered by diet with increased rumination in heifers fed BRC diet. The addition of 4 g/animal/d of a blend of essential oils to the diets of Nellore heifers improved average daily gain, dry matter intake, feed efficiency, and ingestive behavior activities

Sodium reduction by hyposodic salt on quality and chemical composition of hamburgers

This work evaluated the effect of NaCl reduction on the quality and sensorial attributes of hamburgers. Three treatments were tested: control (CON), 100% NaCl; reduction of 25% NaCl (T25), and one with 50% NaCl (T50). The pH, color, lipid oxidation, cooking losses, and texture were analyzed during 120 days of freezing storage. Chemical composition and sensory analyses were performed. The chemical composition was similar for all treatments. The pH value remained within acceptable limits throughout storage. The color, lipid oxidation, cooking losses, and texture were not influenced by the sodium replacement and freezing storage. Sensorial acceptability was also not influenced by sodium reduction. Thus, the results indicated that up to 50% replacement of NaCl by KCl could be carried out in hamburger production without altering the quality and sensorial acceptability

Essential oils in the diet of young bulls: Effect on animal temperament.

Plant extracts and essential oils can be alternative products to antibiotics, because several plants produce secondary metabolites with antimicrobial properties. Additionally, they may act on the olfactory system, which sends signals to the central nervous system releasing endorphins that may affect the feeling of an animal''s welfare while altering an animal''s temperament. This study was conducted to evaluate the animal temperament of 40 young crossbred bulls (one-half Brown Swiss and one-half Nellore) 10 ± 2.2 mo old with an average BW of 219 ± 11.7 kg. Young bulls were randomly assigned to 1 of 5 diets: control, which had no clove or cinnamon; clove leaf included to supply 3, 500 mg/animal per day; clove leaf included to supply 7, 000 mg/animal per day; essential oil of leaf cinnamon to supply 3, 500 mg/animal per day; or essential oil of leaf cinnamon to supply 7, 000 mg/animal per day. The animal temperament was evaluated by calculating the chute score, exit score, and temperament score for periods (each 28 d during 6 periods) and among diets. The data were submitted to an ANOVA using GLM procedures with SAS version 9.0. The diet and period were considered fixed effects, whereas the animals were considered a random effect. Differences between means were evaluated using a Tukey test of 5% of significance. The addition of clove or cinnamon essential oils did not alter (P > 0.05) animal temperament. The analysis of temperament score (P = 0.55), chute score (P = 0.71), and exit score (P = 0.06) did not show significant differences among the diets. The exit score was similar among the 6 periods (1.57, 1.80, 2.98, 2.02, 2.73, and 2.66, respectively); however, chute score and temperament score were greater (P < 0.001) in the first period compared with other periods. The values for chute score were 1.85, 1.40, 1.35, 1.33, 1.20, 1.17, respectively, and the values for temperament score were 2.31, 1.81, 1.67, 1.69, 1.50, and 1.56, respectively, for periods 1 to 6. The results of this study suggest that clove and cinnamon essential oils can be added as an additive in high-grain finished diets without changing the animal temperament

Joint searches between gravitational-wave interferometers and high-energy neutrino telescopes: science reach and analysis strategies

Many of the astrophysical sources and violent phenomena observed in our Universe are potential emitters of gravitational waves (GWs) and high-energy neutrinos (HENs). A network of GW detectors such as LIGO and Virgo can determine the direction/time of GW bursts while the IceCube and ANTARES neutrino telescopes can also provide accurate directional information for HEN events. Requiring the consistency between both, totally independent, detection channels shall enable new searches for cosmic events arriving from potential common sources, of which many extra-galactic objects.Comment: 4 pages. To appear in the Proceedings of the 2d Heidelberg Workshop: "High-Energy Gamma-rays and Neutrinos from Extra-Galactic Sources", Heidelberg (Germany), January 13-16, 200

Validation of photographs usage to evaluate meat visual acceptability of young bulls finished in feedlot fed with or without essential oils

Forty ½ Brown Swiss × ½ Nellore crossbred bulls were distributed into three experimental groups: CON – diet without addition of essential oils; CLO – diet with average 5, 000 mg/animal/day of clove essential oils and CIN – diet with average 5, 000 mg/animal/day of cinnamon essential oils to evaluate three methodologies of visual acceptability: with steaks directly in Trays and Sequential and Random photos. Seventeen consumers evaluated visual appearance of meat using a 9-point structured hedonic scale. CON group presented higher shelf-life than essential oils groups. Trays and Sequential scores were similar in the majority of days; thus digital images could be used to evaluate colour evolution. However, Random photos resulted in lower scores and slower acceptability decrease than Trays and Sequential photos (p < 0.05) among the second and fifth day of display. Random photos presented a lower and more constant standard deviation than Trays and Sequential photos (p < 0.01) indicating that this methodology promoted a higher standard situation for meat colour evaluation

Optimal generalization of power filters for gravitational wave bursts, from single to multiple detectors

Searches for gravitational wave signals which do not have a precise model describing the shape of their waveforms are often performed using power detectors based on a quadratic form of the data. A new, optimal method of generalizing these power detectors so that they operate coherently over a network of interferometers is presented. Such a mode of operation is useful in obtaining better detection efficiencies, and better estimates of the position of the source of the gravitational wave signal. Numerical simulations based on a realistic, computationally efficient hierarchical implementation of the method are used to characterize its efficiency, for detection and for position estimation. The method is shown to be more efficient at detecting signals than an incoherent approach based on coincidences between lists of events. It is also shown to be capable of locating the position of the source.Comment: 16 pages, 5 figure

CHARMM Force Field Parameterization of Peroxisome Proliferator-Activated Receptor γ Ligands

The peroxisome proliferator-activated receptor γ (PPARγ) ligands are important therapeutic drugs for the treatment of type 2 diabetes, obesity and cardiovascular diseases. In particular, partial agonists and non-agonists are interesting targets to reduce glucose levels, presenting few side effects in comparison to full agonists. In this work, we present a set of CHARMM-based parameters of a molecular mechanics force field for two PPARγ ligands, GQ16 and SR1664. GQ16 belongs to the thiazolidinedione class of drugs and it is a PPARγ partial agonist that has been shown to promote the “browning” of white adipose tissue. SR1664 is the precursor of the PPARγ non-agonist class of ligands that activates PPARγ in a non-classical manner. Here, we use quantum chemical calculations consistent with the CHARMM protocol to obtain bonded and non-bonded parameters, including partial atomic charges and effective torsion potentials for both molecules. The newly parameterized models were evaluated by examining the behavior of GQ16 and SR1664 free in water and bound to the ligand binding pocket of PPARγ using molecular dynamics simulations. The potential parameters derived here are readily transferable to a variety of pharmaceutical compounds and similar PPARγ ligands

Noise parametric identification and whitening for LIGO 40-meter interferometer data

We report the analysis we made on data taken by Caltech 40-meter prototype interferometer to identify the noise power spectral density and to whiten the sequence of noise. We concentrate our study on data taken in November 1994, in particular we analyzed two frames of data: the 18nov94.2.frame and the 19nov94.2.frame. We show that it is possible to whiten these data, to a good degree of whiteness, using a high order whitening filter. Moreover we can choose to whiten only restricted band of frequencies around the region we are interested in, obtaining a higher level of whiteness.Comment: 11 pages, 15 figures, accepted for publication by Physical Review

On line power spectra identification and whitening for the noise in interferometric gravitational wave detectors

In this paper we address both to the problem of identifying the noise Power Spectral Density of interferometric detectors by parametric techniques and to the problem of the whitening procedure of the sequence of data. We will concentrate the study on a Power Spectral Density like the one of the Italian-French detector VIRGO and we show that with a reasonable finite number of parameters we succeed in modeling a spectrum like the theoretical one of VIRGO, reproducing all its features. We propose also the use of adaptive techniques to identify and to whiten on line the data of interferometric detectors. We analyze the behavior of the adaptive techniques in the field of stochastic gradient and in the Least Squares ones.Comment: 28 pages, 21 figures, uses iopart.cls accepted for pubblication on Classical and Quantum Gravit