Effects of Voice Compression on the Operation of aN-ISDN/B-ISDN IWF

The significant widespread of N-ISD , which has recently gained momentum, will make it hard for the emerging B-ISD whether to ignore its presence or to phase it out and replace it in the near foreseen future. Consequently, the ATM of the interoperability specification CES-IS V2.0 (af-vtoa-0078.000), which defines emulation standards for circuit characteristics of constant bit-rate (CBR) traffic within ATM. A critical attribute of a circuit emulation service (CES) is to achieve a performance comparable to that are still pending will be addressed. Special interest will be given to devising methods that will enable voice, which is a size able component of the current N-ISD traffic, to be carried efficiently over ATM network. First, a multiplexing technique for voice sources will be presented. Then, assuming that speech silence detection is being used, a technique for dealing with the partially filled cells wil be suggested, analyzed, and then simulated. The results will be then presented and analyzed, followed by conclusions and suggestions

Self-similarity and stationarity of increments in VBR video

AbstractAs self-similarity trail is being detected in many types of traffic, and the Markovian models failing to represent some statistical behaviors, the tools being used for traffic testing are still complex. Our study here is related to VBR video. Its self-similarity and long-range dependence aspects will be tested using a wavelet-based tool. As the test tool requires stationarity of the increments of the traces, a novel testing technique will be suggested for this aim. Then, the degree of self-similarity will be related to both the traces time scale and its statistical measures of spreading

CIITA-induced MHC class II expression in tumor cells: a novel universal strategy of anti-tumor vaccination.

Priming and activation of CD4+ T helper (TH) cells against tumor associated antigens can be achieved after their recognition on antigen presenting cells (APC) only within the context of MHC class II (MHC-II) molecules. We previously reported successful triggering of TH-specific long lasting anti-tumor immune response in H-2d haplotype BALB/c mice using tumor cells genetically modified to express endogenous MHC-II genes (I-A and I-E) after transfection with CIITA (MHC-II transactivator). Now, we investigated the pertinence of this approach in H-2b haplotype C57BL/6 mice that only express I-A molecules due to a defect in their I-E\u3b1 gene. MC38 colon carcinoma cells of the H-2b haplotype were stably transfected with CIITA. Selected MHC-II positive clones were injected into C57BL/6 mice. Complete rejection or significant growth retardation as compared to MHC-II negative parental tumor was obtained. Subsequent challenge of the protected mice with parental tumor proved that the CIITA-transfected tumor engendered efficient anti-tumor vaccination. Then, adoptive cell transfer from the vaccinated mice to na\uefve recipients demonstrated that CD4+ TH cells orchestrate the anti-tumor protection. Finally, the use of CD11c.DTR transgenic mice in which conditional deletion of dendritic cells (DC) can be performed, and the use of Liposomal Clodronate as a depletion agent for macrophages, proved that CIITA-driven MHC-II positive tumor cells act as surrogate APC for priming and activating CD4+ TH cells, without the need of either DC or macrophages. These results demonstrate the validity of CIITA-driven MHC-II+ tumor cells as anti-tumor vaccination tool in mouse models of different haplotypes. Moreover, they prove that expression of a single MHC-II restriction element in tumor cells is sufficient to trigger anti-tumor CD4+ TH cells and, more importantly, demonstrate for the first time that CIITA-driven MHC-II expressing tumor cells can act as professional APCs in vivo to prime na\uefve tumor-specific CD4+ TH cells

The critical exponent for an ordinary fractional differential problem

AbstractWe consider the Cauchy problem for an ordinary fractional differential inequality with a polynomial nonlinearity with variable coefficient. A nonexistence result is proved and the critical exponent separating existence from nonexistence is found. This is proved in the absence of any regularity assumptions

Caracterisation Physico-Chimique Du Lixiviat De La Decharge Sauvage De Meknes

Solid and urban waste produced by the municipality of Meknes amounts to more than 185.103 tons annually. Since 2002 they have been transported to a landfill controlled, wild of an area of 23 hectares on the outskirts of the Commune. This discharge is unfortunately devoid of a leachate treatment device (brownish liquid effluent, produced under the combined action of rainwater and fermentation of buried waste). This study aims to make a physico-chemical characterization and evaluate the states mineral and organic of this leachate. It should be noted that this physicochemical characterization is arbitrary because this discharge will soon be equipped with a waste disposal and recovery center (CEV) using Evalixm as a treatment method. Since 2014, the company '' SUEZ ''Environment began to put in place under control this discharge. For the realization of this characterization, we carried out a series of sampling leachate from June 2014 to June 2015. During this period, the physico-chemical analyzes carried out on these samples, revealed: - low levels of nitrates (NO3 - max = 18,1 mg / L) and phosphates (PO4 3- max = 0,38mg / L) - high levels of ammonium (NH4 + max = 54,13 mg / L) and nitrites (NO 2 - , max = 27,67mg / L). This mineral concentration is translated by a high electrical conductivity which has reached a maximum value of 7.35 10 3 μS / cm. Organic pollution estimated by the pollutant load is important; the values of the Calculated DCO from 1205 to 9207 mg O2 / L with an average of 4808 mg O2 / L, those of DBO are between 53 and 386 mg O2/ L for an average of 157 mg O2 / L. The values of the ratio DBO5 / DCO oscillate between 0.01 and 0.08 with an average of 0.04. This which testifies to the anaerobic character that prevails at the level of the discharge and a probable contamination of the water table. The hydrogen variant (pH) between 6,42 and 8,99 is an annual average of 8,42 which shows that the leachate produced by the landfill is basic. The pH value shows a stagnation (8.42 and 8.23) from one year to the next, reflecting its stability and agin