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A case of acute intestinal anisakiasis has been reported; a nematode larva being found in the submucosa of the ileum of a woman in Jaén (Spain). The source of infection was the ingestion of raw MATERIALS AND METHODSWe have studied a new case of acute intestinal anisakiasis in Spain. On 28 November 1998, a 46-year-old Spanish woman, lifelong resident of Jaén, was admitted to the emergency room at the Hospital Ciudad de Jaén, where her clinical, radiological and analytical report was compatible with acute appendicitis. She had had during two days acute abdominal pain, diarrhea, meteorism, selective pain palpatation in the right ileum fossa, no nausea, vomit or fever and Blumberg sign negative. The laboratory data showed leukocytosis (13.780/mm 3 ), neutrophilia (80%) and 4% of eosinophils. The rest of the red series, white and biochemical, were normal. Plain radiographs of the abdomen and an electrocardiogram were within normal limits. The clinical diagnosis was acute appendicitis. After a McBurney incision, the appendix was found to be normal, with abundant intraperitoneal exudate and inflammatory induration located in the terminal ileum, which showed a microperforation. A prophylactic appendectomy was performed, followed by a wedge resection of the indurated intestinal zone. The layers of the abdominal wall were cleaned and closed. The indurated zone was opened and, in the submucosa of the terminal ileum, a nematode of 2.5 cm in length was found. The neighbouring tissues were analyzed, and the caecal appendix was found with submucosal sclerolipmatosis, and the inflamed ileum was infiltrated with abundant eosinophils.The removed larva, still moving, were placed in saline solution and fixed in 2.5% (v/v) buffered glutaraldehyde (pH 7.2), and examined first under an optical microscope and later processed and examinded under a scanning electron microscope.+ Corresponding

Experimental results for instabilities present in a rotating Hagen-Poiseuille flow are reported in this study through fluid flow visualization. First, we found a very good agreement between the experimental and the theoretical predictions for the onset of convective hydrodynamic instabilities. Our analysis in a space-time domain is able to obtain quantitative data, so the wavelengths and the frequencies are also estimated. The comparison of the predicted theoretical frequencies with the experimental ones shows the suitability of the parallel, spatial and linear stability analysis, even though the problem is spatially developing. Special attention is focused on the transition from convective to absolute instabilities, where we observe that the entire pipe presents wavy patterns, and the experimental frequencies collapse with the theoretical results for the absolute frequencies. Thus, we provide experimental evidence of absolute instabilities in a pipe flow, confirming that the rotating pipe flow may be absolutely unstable for moderate values of Reynolds numbers and low values of the swirl parameter.

In this study, a comprehensive inviscid temporal stability analysis of a compressible round jet is performed for Mach numbers ranging from 1 to 10. We show that in addition to the Kelvin–Helmholtz instability modes, there exist for each azimuthal wavenumber three other types of modes (counterflow subsonic waves, subsonic waves and supersonic waves) whose characteristics are analysed in detail using a WKBJ theory in the limit of large axial wavenumber. The theory is constructed for any velocity and temperature profile. It provides the phase velocity and the spatial structure of the modes and describes qualitatively the effects of base-flow modifications on the mode characteristics. The theoretical predictions are compared with numerical results obtained for an hyperbolic tangent model and a good agreement is demonstrated. The results are also discussed in the context of jet noise. We show how the theory can be used to determine a priori the impact of jet modifications on the noise induced by instability.