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Flow dynamics research is involved in all branches of science and technology: civil and chemical engineering, the automotive industry, energy, etc. Flow dynamics are even more central to aeronautics technology because they provide air lift to planes (non-reacting flow dynamics) as well as the moving impetus through combustion (reacting flow dynamics). The great challenges of flow dynamics require the validation of physical models with relevant lengths ranges spanning a dozen of orders of magnitude, from a few Angstroms, at which atoms and molecules collide and bond (particularly in combustion), to a meter range (the size of a combustion chamber or a wing). Thanks to their non-invasive character, their spectrocopic and imaging possibilities, optical diagnostics are unsurpassed for addressing this enormous challenge., Journal Aerospace Lab, Issue 1, December 2009; ISSN: 2107-6596

This paper deals with lidar systems applied to airflow measurements. The properties of the two main light scattering processes, Rayleigh and Mie scattering, are presented and correlated to general but important rules for lidar design. The Rayleigh lidar developed at Onera for short-range wind speed measurements is also presented, and the Doppler analysis technique using Michelson fringe imagery is briefly discussed., Journal Aerospace Lab, Issue 1, December 2009; ISSN: 2107-6596

For ten years now, Onera has been developing lidar tools for wake vortex detection and studies. Since 2003, new developments based on 1.5 μm fibered laser sources have been achieved in parallel with extensive research work on the laser sources themselves. Three innovative lidars have been developed and are presented in this paper: 1) A mini-lidar, based on a CW (continuous-wave) 2 W / 1.5 μm laser source, for aircraft model wake vortex characterization in a catapult facility. A self-triangulation technique allows the vortex core position to be found with 10 cm error, and the circulation error is 10 %. 2) A pulsed 1.5 μm lidar, based on a 50 μJ / 15 kHz MOPA (Master Oscillator Power Amplifier) source, for lateral wake vortex monitoring at airports. The range is 400 m, the core position error is about ± 2 m and the circulation error is about 10 %. 3) A pulsed 1.5 μm lidar, based on a 120 μJ / 12 kHz MOPA source, for onboard axial wake vortex detection. Ground based lidar tests at Orly airport have demonstrated wake vortex detection up to 1.2 km., Journal Aerospace Lab, Issue 1, December 2009; ISSN: 2107-6596

LEKTI is a 15-domain serine proteinase inhibitor whose defective expression underlies the severe autosomal recessive ichthyosiform skin disease, Netherton syndrome. Here, we show that LEKTI is produced as a precursor rapidly cleaved by furin, generating a variety of single or multidomain LEKTI fragments secreted in cultured keratinocytes and in the epidermis. The identity of these biological fragments (D1, D5, D6, D8-D11, and D9-D15) was inferred from biochemical analysis, using a panel of LEKTI antibodies. The functional inhibitory capacity of each fragment was tested on a panel of serine proteases. All LEKTI fragments, except D1, showed specific and differential inhibition of human kallikreins 5, 7, and 14. The strongest inhibition was observed with D8-D11, toward KLK5. Kinetics analysis revealed that this interaction is rapid and irreversible, reflecting an extremely tight binding complex. We demonstrated that pH variations govern this interaction, leading to the release of active KLK5 from the complex at acidic pH. These results identify KLK5, a key actor of the desquamation process, as the major target of LEKTI. They disclose a new mechanism of skin homeostasis by which the epidermal pH gradient allows precisely regulated KLK5 activity and corneodesmosomal cleavage in the most superficial layers of the stratum corneum.

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Adult T-cell leukemia/lymphoma (ATL) is a malignant proliferation of activated CD4+ T lymphocytes. The disease is almost exclusively found in patients living in retrovirus HTLV-1 endemic areas.In ATL, monoclonal HTLV-1 provirus is integrated into atypical lymphocytes, called clover-leaf lymphocytes. The pathogenic mechanism leading to HTLV-1-induced leukemogenesis remains obscure. The disease generally occurs after a long latency period.The diversity of the clinical presentation has led to the classification of ATL into four subtypes: acute or prototype, lymphoma, chronic, and painless. In the acute form of ATL there is a tumor syndrome associated with paraneoplastic hypercalcemia and a high rate of opportunistic infections due to the immunodepression predominated by cellular immunity.Prognosis is poor for the acute and lymphomatous forms with a median survival of 6 and 10 months respectively. Infectious episodes are frequent, often caused by Pneumocystis carinii, and require systematic prophylaxis. Screening for anguilulosis and prophylaxis is also necessary.

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Pseudomonas aeruginosa elastase was used for peptide-bond synthesis with benzyloxycarbonylalanine and amino acid amides as nucleophilic substrates. Dipeptide-bond synthesis was observed only for hydrophobic amino acid amides. The rate of peptide synthesis, measured by h.p.l.c., was in the decreasing order: PheLeuTyrVal, IleAla, which is consistent with the decreasing order of hydrolysis rates of the corresponding tetrapeptides Ala-Ala-Xaa-Ala. In contrast with thermolysin, Ps. aeruginosa elastase permits the synthesis of tyrosine-containing peptides with tyrosine in the P'1 position. Furthermore, the rates of synthesis for other hydrophobic amino acid amides are higher with elastase than with thermolysin.