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In DS-WCDMA mobile systems such the UMTS, asynchronous cell site operation,assigning different long spreading code to each cell, yields the advantageof flexible system deployment. We can design an indoor system basedon an outdoor one. However, in general, much longer search time isrequired in asynchronous operation than in synchronous. This paperproposes three techniques to take decisions about synchronizationbased on observation of correlated signals. Classical decision criterialike maximum and threshold criterion are presented. A new decisioncriteria that we call Threshold&Max combined decision criteriais analyzed. The results of this new introduced technique is comparedwith the classical ones.  相似文献   
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PURPOSE: A low pregnancy rate in in vitro fertilization (IVF) patients of advanced maternal age may be caused by aneuploidies originating from non disjunction in the first or second meiotic divisions. We introduced genetic testing of oocytes by sampling and fluorescent in situ hybridization (FISH) analysis of the first and second polar bodies, to avoid fertilization and transfer of aneuploid oocytes in IVF patients of advanced maternal age. METHODS: Three hundred and sixty-three IVF patients 34 years and older participated in the study. Using micromanipulation procedures, the first and second polar bodies were removed following their extrusion from the oocytes and studied by FISH, using probes specific for chromosomes 13, 18, and 21 to detect oocytes with common aneuploidies. RESULTS: Of a total of 538 IVF cycles, 3250 oocytes were available for FISH analysis, with conclusive FISH results in 2742 oocytes (84.3%). As many as 1102 (40%) of oocytes were predicted to be aneuploid and not transferred. Of 1640 embryos predicted to be normal, 1145 were transferred in 467 treatment cycles, resulting in 107 pregnancies (23%), from which 67 healthy children have been born, 32 pregnancies spontaneously aborted, and 15 pregnancies are ongoing after being confirmed normal by prenatal diagnosis. CONCLUSIONS: Preimplantation diagnosis by first- and second-polar body FISH analysis allows us to avoid the age-related risk of common aneuploidies in IVF patients of advanced maternal age.  相似文献   
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The mainlobe energy of a member from the class of symbol waveforms with null derivatives at zero crossings is maximized. Thus, a bandlimited pulse shape without intersymbol interference, robust against jitter and timing errors, is obtained. Comparisons to known pulses show advantages for these signals at the expense of bandwidth, which linearly increases with the number of null derivatives  相似文献   
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Laboratory cultures of house dust mites Dermatophagoides pteronyssinus (Trouessart, 1897) and Dermatophagoides farinae Hughes, 1961 were used to study the population dynamics of the mites and the kinetics of antigen appearance. The analysis of extracts obtained after different incubation periods, carried out by SDS-PAGE, immunoblotting, and enzyme-linked immunosorbent assay, allows for the definition of 3 different growth phases: the latency phase (F1); the exponential growth phase (F2) during which the allergenic proteins, including the Der 1 and Der 2 major allergens, were expressed more intensely and in larger quantities; and a final phase (F3), death, in which the lowest rates of allergenic components with a clearly different pattern were seen. The data obtained from this work demonstrates that mite cultures during the maximum growth phase (F2) contain the largest amount of allergenic components as well as the highest major allergen concentrations.  相似文献   
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