660 research outputs found
L'expérience esthétique de l'environnement : une tension sociopolitique entre l'ordinaire et l'extraordinaire ?
Concernant la dimension esthétique des relations des hommes à leur environnement, deux lectures dominent la littérature scientifique : d'un côté, une esthétique qui serait l'apanage d'un regard distancié, associée à l'idée d' « extraordinaire » ; de l'autre côté, une esthétique qui, à force de puiser dans l'ordinaire, finirait par s'y dissoudre au profit d'autres valeurs dominantes utilitaires. À partir d'une analyse d'expériences de villégiature dans des contextes très différents, nous exposons que la dimension esthétique des relations des hommes à leur environnement peut être appréhendée comme une manifestation de la mise en tension entre ordinaire et extraordinaire. Une telle position permet de prendre toute la mesure de la dimension politique de l'esthétique, que l'expérience esthétique se fonde sur l'exclusion « d'autres » ou qu'elle se nourrisse « d'autres » et des liens sociaux qui les unissent. / When we consider aesthetics in human relationships with the physical environment as addressed in scientific literature, two leading approaches emerge. On the one hand aesthetics would appear to be the prerogative of a distanciated look and linked to the notion of extraordinary. On the other, aesthetics would be so immersed in "ordinary life" that if finally dissolves in it and vanishes behind other leading values, such as utilitarian ones. That is particularly obvious in studies of local people's aesthetical experiences. In this paper, we argue that there could be a third way between these two approaches to understanding the aesthetical dimension of human relationships with the environment. We analysed semi-directive interviews with people in two contrasted situations: mountain hikers in the Pyrénées and holiday-makers in the Sensée marshes of northern France. We point out that aesthetics in people's relationships with their physical environment may be seen as manifesting the tension between ordinary and extraordinary. This enables us to perceive the importance of the political dimension of aesthetics, whether visible (experience of a place explicitly incorporates the social relationships that take place in it), or concealed behind an aesthetical experience that appears to be very direct, material and autonomous
The strategic turn of Organic Farming in Europe : a resource based approach of Organic Marketing Initiatives
International audienceThis paper explores the Organic farming " s development potential in Europe by analysing the enterprises capacities to reach a workable structure of the supply chains, in order to market good products at reasonable prices. This study has been carried out in the framework of the OMIaRD project, which aimed to assess the impact of the Organic Marketing Initiatives on Rural Development. The results show that, after a growing phase, most of the OMIs meet strategic problems linked to their ability to face an increasing of collected, processed and marketed volumes. This strategic turn point leads them to take decisions together with their stakeholders, so as the economical and ethical goals are not questioned by the changes to be implemented
Bipolar pulse coding for enhanced performance in Brillouin distributed optical fiber sensors
We propose and experimentally demonstrate the possibility to use a pump signal based on bipolar pulse sequences using single-sideband suppressed-carrier (SSB-SC) modulation in Brillouin optical time-domain analysis (BOTDA) sensors. The SSB-SC modulated pump makes a sequential use of the Brillouin gain and loss spectra, increasing the intensity contrast of the measurements. The method is demonstrated using bipolar Golay codes along a 50 km sensing fiber and 2 m spatial resolution. Results indicate that the use of bipolar sequences provides a higher SNR enhancement and stronger robustness to pump depletion in comparison to BOTDA systems employing conventional unipolar sequences
Bipolar optical pulse coding for performance enhancement in BOTDA sensors
A pump signal based on bipolar pulse coding and single-sideband suppressed-carried (SSB-SC) modulation is proposed for Brillouin optical time-domain analysis (BOTDA) sensors. Making a sequential use of the Brillouin gain and loss spectra, the technique is experimentally validated using bipolar complementary-correlation Golay codes along a 100 km-long fiber and 2 m spatial resolution, fully resolving a 2 m hot-spot at the end of the sensing fiber with no distortion introduced by the decoding algorithm. Experimental results, in good agreement with the theory, indicate that bipolar Golay codes provide a higher signal-to-noise ratio enhancement and stronger robustness to pump depletion in comparison to optimum unipolar pulse codes known for BOTDA sensing
Controlling the Frequency-Temperature Sensitivity of a Cryogenic Sapphire Maser Frequency Standard by Manipulating Fe3+ Spins in the Sapphire Lattice
To create a stable signal from a cryogenic sapphire maser frequency standard,
the frequency-temperature dependence of the supporting Whispering Gallery mode
must be annulled. We report the ability to control this dependence by
manipulating the paramagnetic susceptibility of Fe3+ ions in the sapphire
lattice. We show that the maser signal depends on other Whispering Gallery
modes tuned to the pump signal near 31 GHz, and the annulment point can be
controlled to exist between 5 to 10 K depending on the Fe3+ ion concentration
and the frequency of the pump. This level of control has not been achieved
previously, and will allow improvements in the stability of such devices.Comment: 17 pages, 10 figure
Time/frequency coding for Brillouin distributed sensors
In this paper, we propose a novel coding for long range Brillouin Optical Time Analysis (BOTDA) distributed sensors based on a combination of time and frequency pulses, resulting in an additional coding gain of √2 with respect to traditional intensity-modulated codes. The generation of frequency-chirped pseudo-arbitrary pulses in return-to-zero (RZ) format with a Direct-Digital Synthesizer (DDS) is presented and the coding gain is experimentally verified, perfectly matching its theoretical value
Deciphering the infectious process of Colletotrichum lupini in lupin through transcriptomic and proteomic analysis
The fungal phytopathogen Colletotrichum lupini is responsible for lupin anthracnose, resulting in significant yield losses worldwide. The molecular mechanisms underlying this infectious process are yet to be elucidated. This study proposes to evaluate C. lupini gene expression and protein synthesis during lupin infection, using, respectively, an RNAseq-based transcriptomic approach and a mass spectrometry-based proteomic approach. Patterns of differentially-expressed genes in planta were evaluated from 24 to 84 hours post-inoculation, and compared to in vitro cultures. A total of 897 differentially-expressed genes were identified from C. lupini during interaction with white lupin, of which 520 genes were predicted to have a putative function, including carbohydrate active enzyme, effector, protease or transporter-encoding genes, commonly described as pathogenicity factors for other Colletotrichum species during plant infection, and 377 hypothetical proteins. Simultaneously, a total of 304 proteins produced during the interaction were identified and quantified by mass spectrometry. Taken together, the results highlight that the dynamics of symptoms, gene expression and protein synthesis shared similarities to those of hemibiotrophic pathogens. In addition, a few genes with unknown or poorly-described functions were found to be specifically associated with the early or late stages of infection, suggesting that they may be of importance for pathogenicity. This study, conducted for the first time on a species belonging to the Colletotrichum acutatum species complex, presents an opportunity to deepen functional analyses of the genes involved in the pathogenicity of Colletotrichum spp. during the onset of plant infection
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