Rafidain Journal of Science

The pattern of anti-HCV titer was observed among 24 HCV positive patients for six months in a follow –up study. The study revealed an increase in the titer of HCV antibody of the 24 patients; in the first visit the number of patients with a titer of 1:3, 1:10, 1:100 and 1:300 were 12, 3, 6, 3 respectively, while in the fourth visit the number of patients with the above titers were found in 2,1.9 and 12 patients respectively. This finding reflected the importance of viremia level in the pathogenesis of HCV and its association with the existence of liver disease. The present work also revealed that the changes in the antibody level reflected variation of some liver function tests between first and fourth visit. From this study we can conclud that liver destruction in HCV positive patients can be followed by measuring both anti-HCV titer and variation in liver functions especially ALT level.

Preparation and characterization of new nickel (II) complexes with mixed ligands including salicylaldehyde thiosemicarbazone-STH2 and carboxylic acid-AH2 {salicylic acid-SH2 or anthranilic acid-AnH2 or phthalic acid-PH2} have been studied . The resulted complexes were characterized using different physico-chemical methods from which the general formulaes [Ni2(AH2)2(STH2)2(NO3)2](NO3)2 or [Ni2(AH2)2(STH2)2Xn] have been suggested in neutral medium . Whereas, in basic medium the formula [Ni2(AH)2(STH)2] have been proposed {where X = CO32- or CH3CO2- , n = 2 or 4} . The study suggested that the complexes had octahedral geometries forming dimer (binuclear complexes) .

The U.V. spectra of a series of cinnamylidene (mono and di-substituted) anilines have been studied in CCl4 with the shift reagent Ag(fod). A splitting of the main band into two bands was observed, which may be attributed to the complex formation with the Ag(fod). The equilibrium constant for the process was calculated using the method of Hartman. The U.V. spectra were measured at different temperatures (293-333 0K), the results showed a decrease in K values with increasing temperature. The thermodynamic parameters (AG, AH and AS) were obtained. Application of Skalski method showed that the interaction with Ag(fod) was 1:1.

The electrical conductivities of barium perchlorate [Ba(ClO4)2] in methanol, ethanol, n-propanol and n-butanol are measured at 298K and the conductivity parameters (Λo, KA and R) are calculated. Values of Λo are found to be in the order: MeOH > EtOH > n-Propanol > n-Butanol, but the order is reversed for the values of KA and R. This indicate the increase of ion-solvent interaction and formation of solvent separated ion-pair in the above order.

The concentration of major cations and anions and the total dissolved salt in Tigris and Euphrates Rivers were measured .The longer river course beside the extent and the lithological diversity of Euphrates River basin caused the Euphrates water to have relatively higher ionic contents than Tigris waters .The ionic concentrations of both rivers increase down stream. No appreciable changes in ionic concentration in Tigris and Euphrates waters were observed .Nevertheless,Ca+2 and SO4=exhibit sharp change in their concentrations, this is attributed to the geologic, Hydrogeologic and irrigation agents. According to the total hardness, the Euphrates may be divided into two groups ; hard at the upper reaches and very hard at the middle and lower reaches whereas Tigris water is hard.

In this paper we have investigated a self-scaling technique for the variable metric method to the increase its effectiveness for solving ill-problems. this technique is too effective in NOF;NOC;NOI and NOG, when compared with other established algorithms to solve standard constrained optimization problems .

The aim in this paper is to modify and obtain less execution time of the nonlinear shooting method which used to approximate the solution of the nonlinear boundary-value problems (BVPs) .
The modification is due to replacing single step method (Runge-Kutta for systems) by multi-step method (Adam predictor-corrector of order four for systems) which is used for solving the initial – value problems (IVPs) .