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The problem of timing recovery in wireless mobile receiver systems is critical. This is partly because timing recovery functions must follow rapid parameter changes inherent in mobile systems and partly because both bandwidth and power must be conserved in low signal to noise ratio communication channels. The ultimate goal is therefore to achieve a low bit error rate on the recovered information for improving QoS provisioning to terminal mobile users. Traditional timing recovery methods have over-relied on phase-locked loops for timing information adjustment. However, associated schemes do not exploit code properties. This leads to synchronization difficulties in digital receivers separated from transmitters by lossy channels. In this paper we present a soft timing phase estimation algorithm for wireless mobile receivers in low signal to noise ratios. In order to develop a bandwidth and power efficient timing recovery method for wireless mobile receivers, a raised cosine filter and a multilevel phase shift keying modulation scheme are implemented and no clock signals are transmitted to the receiver. In the proposed method, the receiver exploits the soft decisions computed at each turbo decoding iteration to provide reliable estimates of a soft timing signal, which in turn, improves the decoding time. The derived method, based on sequential minimization techniques, approaches the theoretical Cramer-Rao bound with unbiased estimates within a few iterations.Key Words: discrete polyphase matched filters, maximum likelihood estimators, iterative turbo receivers, log-MAP ba

Nasal obstruction is a frequent symptom of consultation in paediatric otorhinolaryngology. Usually, adenoid hypertrophy is the cause. Sometimes the examination reveals the presence of polyps in the nose. The antrochoanal polyp of Killian is particularly frequent in childhood. The obstruction is usually unilateral, but the posterior extension of a bulky polyp to the oropharynx can cause a major discomfort, sometimes a respiratory distress. We report the observation of a 10-year-old patient presenting a bulky polyp of Killian, visible in the oropharynx and then discuss the features of this polyp in the literature.

Annales Francaises d'Oto-Rhino-Laryngologie et de pathologie cervico-faciale - Vol. 122 - N° 3 - p. 127-133

Background: Primary adenocarcinomas of the small intestine are rare, and the genetic mechanisms involved in their carcinogenesis remain unclear. Aim: To examine the expression of candidate proteins in small intestinal adenocarcinomas by immunohistochemistry performed on tissue microarrays (TMAs). Methods: Twenty seven primary sporadic small intestinal adenocarcinomas were analysed. The TMA technique was validated by comparing immunohistochemical labelling of hMLH1 and hMSH2 on TMAs and the tissue sections they derived from. The expression of Smad4, hMSH6, β catenin, and p53 was investigated and results compared with those obtained in 14 malignant ampullary tumours. Results: TMA technology with threefold redundancy adequately represented the immunohistochemical pattern of small intestinal adenocarcinomas. Loss of hMLH1 expression, but not hMSH2 or hMSH6, was seen in two of 27 small intestinal adenocarcinomas. All ampullary tumours showed nuclear staining for hMSH2 and hMSH6. One case showed lack of immunostaining for hMLH1. Smad4 expression was absent in five small intestinal adenocarcinomas and two ampullary tumours. Overexpression of p53 was detected in the nuclei of 14 of the 27 small intestinal adenocarcinomas, and five of the 14 ampullary tumours. Nuclear or cytoplasmic expression of β catenin was present in all specimens. Conclusion: Inactivation of the SMAD4/DPC4 gene seems to be involved in small intestinal adenocarcinoma tumorigenesis. Overexpression of p53 and abnormal expression of β catenin are two common events, unlike the loss of expression of the DNA mismatch repair proteins (hMLH1, hMSH2, and hMSH6). The carcinogenetic process appears to be similar in small intestinal adenocarcinomas and malignant ampullary tumours.

INTRODUCTION There are two types of autoimmune haemolytic anemia, idiopathic or associated to other disorders (infections, thyroidal diseases, cancer.). The treatment of this particular anemia depends on the primary or secondary feature. EXEGESIS We report the case of a 76-year old woman, presenting an autoimmune haemolytic anemia with a positive direct Coombs test in IgG. The corticodependance of this anemia after 6 months of treatment had indicated a splenectomy. During surgery, a gastric stromal tumor was discovered. After removal of the tumor and splenectomy, the haematological symptomatology quickely disappeared and induced the negativation of the Coombs test within a post operative period going from 7 to 14 months, without any immunosuppressor treatment. CONCLUSION Splenectomy does not induce the negativation of a Coombs test in an autoimmune haemolytic anemia, someaning that there is a link between the anemia and the tumor. This observation is completed by a review the literature.