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We present preliminary results on a study of the 2--850 micron SEDs of a sample of 30 FIRBACK galaxies selected at 170 micron. These sources are representative of the brightest ~10% of the Cosmic Infrared Background. They are a mixture of mostly local (z<~0.3) starforming galaxies, and a tail of ULIGs that extend up to z~1, and are likely to be a similar population to faint SCUBA sources. We use archival Spitzer IRAC and MIPS data to extend the spectral coverage to the mid-IR regime, resulting in an unprecended (for this redshift range) census of their infrared SEDs. This allows us to study in far greater detail this important population linking the near-IR stellar emission with PAH and thermal dust emission. We do this using a Markov Chain Monte Carlo method, which easily allows for the inclusion of ~6 free parameters, as well as an estimate of parameter uncertainties and correlations. Comment: 5 pages, 3 figures. Proceeding for the conference "Starbursts: From 30 Doradus to Lyman Break Galaxies", held in Cambridge (UK) in September, 2004

International audience; no abstract

International audience; In the context of the severe decrease in temperate eel abundance, understanding and control of eel maturation has strong interest for scientific and commercial purposes. Possible use of ultrasonography for improvement of sex determination and maturation monitoring in silver eel was investigated. Gonads of 96 Anguilla anguilla silver eels were observed using portable equipment associated to a 6-15MHz probe, and sex determination was tried before artificial induction of maturation. To estimate gonad mass and monitor individual gonadosomatic index (GSI) in females, cross-sectional images were captured at different times of maturation and gonad length was measured at scanning. Two methods were tried for ovary mass estimation using ultrasonography: one based on a linear model and another on calculating ovary volume from a representation of gonad shape. Ultrasonography resulted in 100% success in sex determination. Ovary mass estimated by ultrasonography was strongly correlated to true ovary mass (R2=0.97). The use of a linear model for gonad mass and then GSI estimation seemed more appropriate than the use of a representation of gonad shape. Evolution of GSI estimates during maturation supports possible detection of early inter-individual differences in maturation using ultrasonography in female silver eels. This non-invasive tool can then obviously be exploited to improve sex determination in silver eels caught in the wild and to monitor maturation at the individual level. Ultrasonography thus has great potential for use in eel both for conservation and aquaculture. To our knowledge, this is the first report on the use of ultrasonography on eels or any anguillid species.

We present a search for galaxy-scale strong gravitational lenses in the initial 2 500 square degrees of the Canada-France Imaging Survey (CFIS). We designed a convolutional neural network (CNN) committee that we applied to a selection of 2 344 002 exquisite-seeing $r$-band images of color-selected luminous red galaxies (LRGs). Our classification uses a realistic training set where the lensing galaxies and the lensed sources are both taken from real data, namely the CFIS $r$-band images themselves and the Hubble Space Telescope (HST). A total of 9 460 candidates obtain a score above 0.5 with the CNN committee. After a visual inspection of the candidates, we find a total of 133 lens candidates, of which 104 are completely new. The set of false positives mainly contains ring, spiral, and merger galaxies, and to a lesser extent galaxies with nearby companions. We classify 32 of the lens candidates as secure lenses and 101 as maybe lenses. For the 32 highest quality lenses, we also fit a singular isothermal ellipsoid mass profile with external shear along with an elliptical Sersic profile for the lens and source light. This automated modeling step provides distributions of properties for both sources and lenses that have Einstein radii in the range $0.5\arcsec<θ_E<2.5\arcsec$. Finally, we introduce a new lens and/or source single-band deblending algorithm based on auto-encoder representation of our candidates. This is the first time an end-to-end lens-finding and modeling pipeline is assembled together, in view of future lens searches in a single band, as will be possible with Euclid. 29 pages, 21 figures, accepted by A&A, in press

Finite element models (FEM) dedicated to vertebral fracture simulations rarely take into account the rate dependency of the bone material properties due to limited available data. This study aims to calibrate the mechanical properties of a vertebral body FEM using an inverse method based on experiments performed at slow and fast dynamic loading conditions. A detailed FEM of a human lumbar vertebral body (23,394 elements) was developed and tested under compression at 2,500 and 10 mm s⁻¹. A central composite design was used to adjust the mechanical properties (Young modulus, yield stress, and yield strain) while optimizing four criteria (ultimate strain and stress of cortical and trabecular bone) until the failure load and energy at failure reached experimental results from the literature. At 2,500 mm s⁻¹, results from the calibrated simulation were in good agreement with the average experimental data (1.5% difference for the failure load and 0.1% for the energy). At 10 mm s⁻¹, they were in good agreement with the average experimental failure load (0.6% difference), and within one standard deviation of the reported range of energy to failure. The proposed method provides a relevant mean to identify the mechanical properties of the vertebral body in dynamic loadings.

Review Methodology: We started off from existing reports on land degradation and ecosystem valuations [1, 2]. We also reviewed existing economic reviews by Nkonya et al. [3], Adhikari and Nadella [4], Requier-Desjardins [5] and Requier-Desjardins et al. [6]. In addition, we searched the following database and journals: Google Scholar, Land Degradation and Development, Journal of Agricultural and Resource Economics, Journal of Environmental Economics and Management, Environmental and Resource Economics, Ecological Economics (keyword search terms used: land degradation, cost of land degradation, economic valuation, economic valuation and developing country, payments for ecosystem services, payments for ecosystem services and developing countries). We used the references from the articles obtained by this method to check for additional relevant material. We also spoke to colleagues and checked for any upcoming studies not yet published. Land degradation has become a growing concern with the current increase in demand for arable land. Sustainable land management and land restoration practices are required in order to meet the demands to provide food and other services. Adoption of improved practices has, however, not been widespread partly because of a lack of clarity on the true economic value and setting of proper financial incentives. This review focuses on the economic costs of land degradation as a prelude to two ongoing initiatives involving the United Nations Convention to Combat Desertification (UNCCD). We review how ecosystem services derived from land have been economically valued to date. Economic valuation has mostly focused on the use value of provisioning services and cultural services, with limited valuation of non-use value of cultural services. Also, no unique valuation method has been applied following methodological developments, varying study objectives and data availability constraints. These factors impair coherent and consistent estimation of the total economic value of land degradation across countries. We identify a need to develop harmonized valuation methods to estimate total economic value under strong data and capacity constraints. We propose two alternative frameworks for harmonized total economic valuation of land degradation at country level to guide further research in making environmental valuation more relevant and practical under strong data and capacity constraints.

Electromagnetic bang gap (EBG) materials are periodic structures characterized by forbidden propagation of electromagnetic waves in their band-gap and by the ability to open localized modes inside the band-gap by introducing defects. Cylindrical electromagnetic band gap (CEBG) structures are radially and circularly periodic, and they present pass-band and stop-band to cylindrical electromagnetic waves. By applying a horn-shaped defect in these structures, it has been shown that a re-configurable directive pattern can be obtained. In (P. Ratasjack et al., 2004), experimental results for a reconfigurable CEBG-based antenna have been presented, whereas in (H. Boutayeb et al., 2006), an analysis of the transmission coefficient of CEBG structures and experimental results for a CEBG directive antenna have been proposed. In (H. Boutayeb et al., 2006), a new defect configuration has been proposed for reducing the power supply, but this solution leads to a narrower band. In this paper, new defect configurations are analyzed in order to reduce the number of active elements and the required power supply in CEBG-based agile antennas. The solution with the widest bandwidth is indicated.