335 research outputs found
Ătude du procĂ©dĂ© d'Ă©vaporation des extraits de canneberge et bleuet sur la base des rendements Ă©nergĂ©tiques et de leur qualitĂ©
Le projet vise lâoptimisation de lâĂ©vaporation industrielle sous vide des extraits liquides de petits fruits, phase du procĂ©dĂ© de production dâextraits nutraceutiques, afin dâaugmenter son efficacitĂ© Ă©nergĂ©tique, tout en conservant une grande qualitĂ© de produit. Nous avons Ă©tudiĂ© lâimpact de la tempĂ©rature dâĂ©vaporation (55, 65 et 75 (C) sur trois paramĂštres : la consommation Ă©nergĂ©tique, le dĂ©bit dâĂ©vaporation et la qualitĂ© des extraits. La consommation a Ă©tĂ© calculĂ©e par diffĂ©rentes mesures sur lâĂ©tat du systĂšme et du produit. Les dĂ©bits ont Ă©tĂ© mesurĂ©s par des diffĂ©rentiels de niveaux de rĂ©servoirs puis la qualitĂ© Ă©valuĂ©e selon la mĂ©thode Folin-Ciocalteu. Au niveau de la consommation, celle-ci passe de 0,358 Ă 0,373 kWh/l en passant de 55 Ă 75°C. Pour les dĂ©bits, ceux-ci augmentent de 462 l/h Ă 902 l/h en passant de 55 Ă 75 (C. En ce qui a trait Ă la qualitĂ©, aucun extrait ne prĂ©sente de signes de dĂ©tĂ©rioration.The objective of this project is to optimize the evaporation of small fruit liquid extracts, a crucial step in the transformation process of nutraceutical extract production in order to increase its energetic efficiency while keeping a good product quality. The impact of temperature (55, 65 and 75°C) was studied over 3 main parameters; the energetic consumption, the vaporization rate and the extract quality. Its consumption was calculated based on measurements made on the state of the system and on the product. The vaporization rates were measured with level differentials on retention tanks and the product quality evaluation was based on the Folin-Ciocalteu method. For the energetic consumption, they increase from 0.358 to 0.373 kWh/l when passing from 55 to 75 °C. For the vaporization rates, they increase from 462 l/h to 902 l/h when passing from 55 to 75 °C. As for the quality, none of the extracts presents signs of deterioration
Fourfold oscillations and anomalous magnetic irreversibility of magnetoresistance in the non-metallic regime of Pr1.85Ce0.15CuO4
Using magnetoresistance measurements as a function of applied magnetic field
and its direction of application, we present sharp angular-dependent
magnetoresistance oscillations for the electron-doped cuprates in their
low-temperature non-metallic regime. The presence of irreversibility in the
magnetoresistance measurements and the related strong anisotropy of the field
dependence for different in-plane magnetic field orientations indicate that
magnetic domains play an important role for the determination of electronic
properties. These domains are likely related to the stripe phase reported
previously in hole-doped cuprates.Comment: 11 pages, 5 figure
Venir de (+ infinitive):an immediate anteriority marker in French
This paper deals with the grammaticalization of venir into aspectual auxiliary of immediate anteriority, against the traditional approach (Gougenheim 1929/1971) according to which venir de + inf., would express recent past and so would be a temporal auxiliary. On the basis of the (revised) Reichenbachian model, it shows that venir de + inf. bears upon the relationship between R and E (aspect) and not on the relationship between R and S (time). This analysis allows explain why venir, in this periphrasis, is defective (i.e. why venir cannot be conjugated in the passé simple or in any compound tense)
Establishment and analysis of a reference transcriptome for Spodoptera frugiperda
International audienceBackground Spodoptera frugiperda (Noctuidae) is a major agricultural pest throughout the American continent. The highly polyphagous larvae are frequently devastating crops of importance such as corn, sorghum, cotton and grass. In addition, the Sf9 cell line, widely used in biochemistry for in vitro protein production, is derived from S. frugiperda tissues. Many research groups are using S. frugiperda as a model organism to investigate questions such as plant adaptation, pest behavior or resistance to pesticides.ResultsIn this study, we constructed a reference transcriptome assembly (Sf_TR2012b) of RNA sequences obtained from more than 35âS. frugiperda developmental time-points and tissue samples. We assessed the quality of this reference transcriptome by annotating a ubiquitous gene family - ribosomal proteins - as well as gene families that have a more constrained spatio-temporal expression and are involved in development, immunity and olfaction. We also provide a time-course of expression that we used to characterize the transcriptional regulation of the gene families studied.ConclusionWe conclude that the Sf_TR2012b transcriptome is a valid reference transcriptome. While its reliability decreases for the detection and annotation of genes under strong transcriptional constraint we still recover a fair percentage of tissue-specific transcripts. That allowed us to explore the spatial and temporal expression of genes and to observe that some olfactory receptors are expressed in antennae and palps but also in other non related tissues such as fat bodies. Similarly, we observed an interesting interplay of gene families involved in immunity between fat bodies and antennae
Myosin heavy chain and physiological adaptation of the rat diaphragm in elastase-induced emphysema
BACKGROUND: Several physiological adaptations occur in the respiratory muscles in rodent models of elastase-induced emphysema. Although the contractile properties of the diaphragm are altered in a way that suggests expression of slower isoforms of myosin heavy chain (MHC), it has been difficult to demonstrate a shift in MHCs in an animal model that corresponds to the shift toward slower MHCs seen in human emphysema. METHODS: We sought to identify MHC and corresponding physiological changes in the diaphragms of rats with elastase-induced emphysema. Nine rats with emphysema and 11 control rats were studied 10 months after instillation with elastase. MHC isoform composition was determined by both reverse transcriptase polymerase chain reaction (RT-PCR) and immunocytochemistry by using specific probes able to identify all known adult isoforms. Physiological adaptation was studied on diaphragm strips stimulated in vitro. RESULTS: In addition to confirming that emphysematous diaphragm has a decreased fatigability, we identified a significantly longer time-to-peak-tension (63.9 ± 2.7 ms versus 53.9 ± 2.4 ms). At both the RNA (RT-PCR) and protein (immunocytochemistry) levels, we found a significant decrease in the fastest, MHC isoform (IIb) in emphysema. CONCLUSION: This is the first demonstration of MHC shifts and corresponding physiological changes in the diaphragm in an animal model of emphysema. It is established that rodent emphysema, like human emphysema, does result in a physiologically significant shift toward slower diaphragmatic MHC isoforms. In the rat, this occurs at the faster end of the MHC spectrum than in humans
First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data
Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of
continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a
fully coherent search, based on matched filtering, which uses the position and rotational parameters
obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto-
noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch
between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have
been developed, allowing a fully coherent search for gravitational waves from known pulsars over a
fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of
11 pulsars using data from Advanced LIGOâs first observing run. Although we have found several initial
outliers, further studies show no significant evidence for the presence of a gravitational wave signal.
Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of
the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for
the first time. For an additional 3 targets, the median upper limit across the search bands is below the
spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried
out so far
Membrane-mediated interactions
Interactions mediated by the cell membrane between inclusions, such as
membrane proteins or antimicrobial peptides, play important roles in their
biological activity. They also constitute a fascinating challenge for
physicists, since they test the boundaries of our understanding of
self-assembled lipid membranes, which are remarkable examples of
two-dimensional complex fluids. Inclusions can couple to various degrees of
freedom of the membrane, resulting in different types of interactions. In this
chapter, we review the membrane-mediated interactions that arise from direct
constraints imposed by inclusions on the shape of the membrane. These effects
are generic and do not depend on specific chemical interactions. Hence, they
can be studied using coarse-grained soft matter descriptions. We deal with
long-range membrane-mediated interactions due to the constraints imposed by
inclusions on membrane curvature and on its fluctuations. We also discuss the
shorter-range interactions that arise from the constraints on membrane
thickness imposed by inclusions presenting a hydrophobic mismatch with the
membrane.Comment: 38 pages, 10 figures, pre-submission version. In: Bassereau P., Sens
P. (eds) Physics of Biological Membranes. Springer, Cha
A Standard Siren Measurement of the Hubble Constant from GW170817 without the Electromagnetic Counterpart
We perform a statistical standard siren analysis of GW170817. Our analysis does not utilize knowledge of NGC 4993 as the unique host galaxy of the optical counterpart to GW170817. Instead, we consider each galaxy within the GW170817 localization region as a potential host; combining the redshifts from all of the galaxies with the distance estimate from GW170817 provides an estimate of the Hubble constant, H 0. Considering all galaxies brighter than as equally likely to host a binary neutron star merger, we find km sâ1 Mpcâ1 (maximum a posteriori and 68.3% highest density posterior interval; assuming a flat H 0 prior in the range km sâ1 Mpcâ1). We explore the dependence of our results on the thresholds by which galaxies are included in our sample, and we show that weighting the host galaxies by stellar mass or star formation rate provides entirely consistent results with potentially tighter constraints. By applying the method to simulated gravitational-wave events and a realistic galaxy catalog we show that, because of the small localization volume, this statistical standard siren analysis of GW170817 provides an unusually informative (top 10%) constraint. Under optimistic assumptions for galaxy completeness and redshift uncertainty, we find that dark binary neutron star measurements of H 0 will converge as , where N is the number of sources. While these statistical estimates are inferior to the value from the counterpart standard siren measurement utilizing NGC 4993 as the unique host, km sâ1 Mpcâ1 (determined from the same publicly available data), our analysis is a proof-of-principle demonstration of the statistical approach first proposed by Bernard Schutz over 30 yr ago
Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light
Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometerâs dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1ââdB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%â8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded
Quantum Backaction on kg-Scale Mirrors: Observation of Radiation Pressure Noise in the Advanced Virgo Detector
The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise
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