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The principle of an optical technique for simultaneous velocity, size, and concentration in suspension measurements of spherical droplets and cylindrical jets is proposed. This technique is based on phase Doppler anemometry working in the dual burst technique configuration. The particle size and velocity are deduced from the reflected signal phase and frequency, whereas the amplitude ratio between the refracted and the reflected signals is used for measuring the concentration of small scatterers inside the particles. Numerical simulations, based on geometrical optics and a Monte Carlo model, and an experimental validation test on cylindrical jets made of various suspensions, are used to validate the principle of the proposed technique. It is believed that this new technique could be useful in investigating processes in which liquid suspensions are sprayed for surface coating, drying, or combustion applications.

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An optical device for measuring high particle concentrations is presented. The sensor consists of two optical fibers used for the emission and reception of the light scattered by particles in suspension. To describe the light path in this medium, we developed a Monte Carlo calculation including a mean free path, a phase function for particle scattering, and an absorption rate. A similarity law links concentration variations to a homothetic space transformation. A comparison between our calculation and experimental data is given for well-stirred, dense suspensions of silica particles with different sizes. A good fit is found when the model parameters (mean free path and phase function) are chosen according to the data given by a particle sizer.

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Ano-rectal myectomy, described by B. Duhamel in 1965, is the logical therapy of rectoanal achalasia; an experience of 117 cases is reported. Clinical examination and radiological investigations have been made prior to surgery. This surgical procedure is simple, without complication. Three kinds of rectoanal achalasia are described: achalasia with structural change of the internal sphincter (fibrosis, sclerosis); achalasia with a functional sphincteric disorder (with normal histology); achalasia with intrinsic innervation abnormality. Excellent results have been observed in the two first groups but more variable successful results in the third group which concerns short segments of Hirschsprung's disease.

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Eighty-five patients with nodular lymphoma diagnosed between 1968 and 1975 were followed up for long periods and were treated by either conventional methods (local radiotherapy and single drug chemotherapy) or by more intensive therapeutic regimens, such as initial combined M.O.P.P. therapy and maintenance treatment with chlorambucil with or without further courses of M.O.P.P. Long-term follow-ups have brought to light some interesting points concerning the prognosis. Dissemination of the disease and large-cell histological pattern were, as already known, unfavourable factors. Neither age nor sex, nor bone-marrow involvement seemed to have any influence. Obtaining complete remissions improved the prognosis, but intensifying the initial and maintenance treatments proved disappointing: the survival rate remained the same, and the incidence of drug induced leukaemias was high. Indeed, relapses appeared to be less responsive to treatment when the patient had initially received multiple chemotherapy. However, in view of the high death rate of the disease (one-third of the patients in this series died within the first 5 years), trying new therapeutic regimens in the hope of obtaining better results, as has been done in Hodgkin's disease, would be fully justified.

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Formation of nitrosamines, after absorption of nitrite and secondary or tertiary amines in the gastro-intestinal tract, is used as a chemical test of carcinogenicity in the Rat. We have confirmed the carcinogenic power of a tertiary amine association: aminophenazone, and sodium nitrite giving dimethyl-nitrosamine in Sprague Dawley rats: both substances are administered at low and high concentrations in drinking water. We have studied simultaneously, the propyphenazone/sodium nitrite association in the same experimental conditions without carcinogenic power: --treatment duration: thirty weeks, --study duration: two years with observation of carcinogenic reactions, --verification of data: control and substances given independently.

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84 bone marrow biopsies were analysed by quantification methods with Classimat. The initial diagnosis was: idiopathic myelofibrosis with splenomegaly. A previous study divided the patients among three categories, according to the classification in three progressive stages of the bone marrow disease. The quantitative lecture was done after reticulin coloration, "in blind", and on several biopsies from the same patient. The results show good correlation with classical histologic methods. The quantitative measure of fibrosis is already important as soon as the first stages of the disease. Correlations with prognosis are more difficult to define.

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84 bone marrow biopsies were analysed by quantification methods with Classimat. The initial diagnosis was: idiopathic myelofibrosis with splenomegaly. A previous study divided the patients among three categories, according to the classification in three progressive stages of the bone marrow disease. The quantitative lecture was done after reticulin coloration, "in blind", and on several biopsies from the same patient. The results show good correlation with classical histologic methods. The quantitative measure of fibrosis is already important as soon as the first stages of the disease. Correlations with prognosis are more difficult to define.

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