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International audience; The scale-dependent turbulent convection velocity of streamwise velocity fluctuations resolved by large eddy simulation is investigated for the first time across the whole profile of a zero-pressure-gradient spatially developing smooth flat plate boundary layer at Re_θ = 13 000. The high Reynolds number and streamwise heterogeneity constraints motivate the derivation of a dedicated new method to assess the frequency-dependent convection velocity from time signals and their local streamwise derivative, using estimates of power spectral densities (PSDs). This method is inspired by del Álamo & Jiménez (J. Fluid Mech., vol. 640, 2009, pp. 5–26), who treated a lower Reynolds number channel flow with a method suited to spectral direct numerical simulations of streamwise homogeneous flows. Reconstruction of the streamwise spectrum from the time spectrum using the scale-dependent convection velocity is illustrated and compared with classical strategies. The new method inherently includes not only the assessment of the validity of Taylor’s hypothesis, whose trend is remarkably consistent with theoretical predictions by Lin (Q. Appl. Maths, vol. X(4), 1953, 154–165), but also the definition of a global convection velocity accounting for any arbitrary frequency band. This global velocity is shown to coincide with a correlation-based method widely used in experiments. In addition to the mathematical least-squares definition of this velocity, new interpretations based on the flow physics and turbulent micro time scales are presented. Further, the group velocity is assessed and its relation to convection is discussed.

International audience; A method inspired by del Alamo et al. [1] is derived to assess the wavelength-dependent convection velocity in a zero pressure gradient spatially developing flat plate turbulent boundary layer at Retheta = 13 000 for all wavelengths and all wall distances, using only estimates of the time power spectral density of the streamwise velocity and of its local spatial derivative. The resulting global convection velocity has a least-squares interpretation and is easily related to the wavelength-dependent convection velocity. The method intrinsically provides an estimation of the validity of Taylor’s hypothesis by a correlation coefficient identical to the one from [1]. The results reveal some similarities between the convection of the superstructures, the hairpin packets and the near-wall structures. The convection velocity of the superstructures is isolated by restricting the global convection velocity to the largest wavelengths. The spatial spectrum is estimated from the temporal spectrum using the frequency-dependent convection velocity. The results are consistent with a classical correlation-based evaluation.1. del Alamo, J.C., Jimenez, J.: Estimation of turbulent convection velocities and corrections to Taylor’s approximation. Journal of Fluid Mechanics 640, 5–26 (2009)

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Apocrine adenocarcinoma of the skin is a rare and, most of the time, clinically misdiagnosed malignant adnexal tumour. A 66-year-old female patient presented with an asymptomatic swelling of the left nipple that on pathological evaluation was confirmed as an apocrine adenocarcinoma. Surgery is to be considered as the mean treatment for such a lesion and the diagnosis is always difficult to establish. To our best knowledge, this is only the second reported apocrine adenocarcinoma arising from a nipple and the first presenting with Paget's phenomenon.

Anthracycline-based regimens are among the most active but also with greater risk of both acute and long-term side effects, namely cardiotoxicity. Predictive markers of response to anthracyclines are therefore essential. Topoisomerase-IIalpha (topo-II) is the target of anthracyclines and preliminary data suggest its promising role as a predictive marker of sensitivity to these drugs. After screening a population of about 350 patients with locally advanced or metastatic breast cancer, two subgroups were selected for the present analysis: a study group (31 patients), composed of 14 complete responders (CR-a) and 17 true non-responders (PD-a) to anthracycline-based CT, and a control group (28 patients), composed of 7 CR (CR-t) and 21 true non-responders (PD-t) to taxane-based CT. True non-responders were defined as progressive disease (PD) within the first three cycles of CT. Archival tumor samples of these patients were collected, biological markers evaluated and their status correlated with response to therapy. HER-2 and topo-II gene status were evaluated by FISH (Vysis multi-color probe-positivity cut-off:/=2 ratio for HER-2 and/=1.5 for topo-II), topo-II protein was evaluated by IHC (positivity cut-off10%). All cases in which HER-2 gene was non-amplified did not show topo-II gene aberrations. No association was found between HER-2 gene amplification and response to anthracyclines (5/14 (36%) CR and 5/17 (29%) PD to anthracycline-based CT were HER-2+). The topo-II gene was amplified in 3/14 (21%) CR but only in 1/17 (6%) PD to anthracyclines. Amplification of the topo-II gene was seen in 1/7 (14%) CR and in 3/21 (14%) PD to a taxane-based CT. Topo-II protein was overexpressed in 6/11 (55%) CR and in 2/17 (12%) PD to anthracyclines, while in the control group, overexpression was seen in 5/7 (71%) CR and 8/20 (40%) PD.i) HER-2 gene amplification did not seem to be correlated with response to anthracyclines. ii) Both topo-II gene amplification and protein overexpression seem to correlate with response to anthracyclines, although other factors, such as p53 and cell proliferation, are most likely to be involved. iii) The role of combined evaluation of several relevant markers and of potential 'molecular signatures' are currently being evaluated in prospective randomized clinical trials.

*INRA Unite Regionale de Documentation B.V. 1540 21034 Dijon Cedex (FRA) Diffusion du document : INRA Unite Regionale de Documentation B.V. 1540 21034 Dijon Cedex (FRA) Diplôme : Maîtrise