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Cognitive Heterogeneous Network (CHN) is a network that provides heterogeneous services on a cognitive radio basis. The existence of such heterogeneous services introduces a syndrome of concurrent problems. Handling each problem separately may result in more consequences. This paper aims to mitigate the combined effects of noise uncertainty and asynchronous primary user occurrence within the sensing interval of the secondary user in cognitive heterogeneous network. The paper proposes a double threshold energy detection method based on unequal scale sampling criteria. An analytic formula is deduced for both thresholds employing the power scaling criteria. Simulation results show a complete agreement with the performance expectations in terms of increased probability of detection while keeping the false alarm probability within the required limits, which is guaranteed by plotting the ROC curves. Moreover, an optimal threshold is formulated to minimize the overall detection errors, that led to further enhancements in performance as illustrated also via simulations.

Colchicine alone or following praziquantel was given to mice infected with Schistosoma mansoni either 6 or 10 weeks post infection. Praziquantel increased body weight gain, histologically reduced number, diameter and cellularity of granuloma and improved liver function parameters. Early praziquantel therapy decreased hepatic collagen content as detected by the colorimetric method and the serum procollagen propeptide (PIIIP), while later treatment at the 10th week of infection increased hepatic collagen content and serum PIIIP. Colchicine therapy significantly decreased body weight gain with significant weight loss after early treatment. Colchicine did not change the histologic picture of schistosomal liver fibrosis; it induced a detectable hepatocytic injury recorded ultrastructurally and histologically with excitation of the inflammatory reaction in the granuloma and in portal tracts after early treatment. Excess pigmentation in macrophages and Kupffer cells, binucleation and large sized hepatocytic nuclei were evident after colchicine therapy. Colchicine increased hepatic collagen content microgram/mg protein, raised globulin and total serum protein and normalized the raised serum PIIIP of infected mice, but had no effect on PIIIP of normal mice. Early cessation of schistosomal infection evidently minimized the adverse effects of colchicine.