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A composite sample of FeAl2O3were synthesized by using mixture of paraffin wax and a powder of Al2O3 (0.07gm.) with iron granular Fe (0.01 gm.) of different particle sizes (63μm, 73μm, 212μm and 300μm). Where paraffin wax was melted using a temperature source (heater) with 328 K, then the granular volume of composite FeAl2O3 powder was added to paraffin wax by manual mixing until the mixture was homogeneous and then deposited on slices of aluminum in laboratory conditions. The Characteristics of (current- voltage) were measured to various particle sizes. The electrical conductivity was estimated as a function of various temperature range. The conductivity values of this composite doped of FeAl2O3 increasing with temperature increases. Also, the activation energies Ea for the composite samples have been found (4.1x10-4 –2.9x10-4) eV. Beside that the mechanisms of electrical conductivity were studied and identified in support of Schottky and Frankel effect mechanisms.

Background: The association of diabetes mellitus, nighttime blood pressure dipping and nonarteritic ischemic optic neuropathy is inconclusive. There has been no study to test this association among Arab Patients. Objectives: This study aims to test the association between diabetes mellitus, nighttime blood pressure dipping and nonarteritic ischemic optic neuropathy among cohort of patients from Basrah, Southern Iraq. Methods: This was a cross-sectional study on patients with nonarteritic ischemic optic neuropathy conducted at the ophthalmology clinic at Faiha Teaching Hospital in 2018. Patients with nonarteritic ischemic optic neuropathy were screened for diabetes mellitus. Ambulatory blood pressure monitor was attached to some of the participants for 24 hours. Nighttime blood pressure dipping was classified into 4 categories:  normal, blunted, severe and reverse. Results: A total of 74 patients with nonarteritic ischemic optic neuropathy were included. Females constituted 64.9 % of the cases. Forty patients (53.3%) were found to have diabetes mellitus. While 41 participants (55.5 %) were hypertensive. Nocturnal dipping of blood pressure was measured in 38 patients. Only 6 (15.7%) of them had severe dipping. Conclusions: There may be an association between diabetes mellitus but not nighttime blood pressure dipping with nonarteritic ischemic optic neuropathy.  

Thick films of composites of iron–aluminium oxide (FeAl2O3) were prepared by mixing paraffin wax with a powder of aluminium oxide (Al2O3) and iron granular (Fe) (600 μm in size). The current–voltage (I-V) characteristic was measured at different temperatures (293– 328 K). The electrical conductivity was also measured at those temperature levels. It was noted that an increase in temperature leads to an increase in electrical conductivity. The activation energies (Ea) were determined to be 0.357–0.125 ev; the electrical conductivity mechanism was identified as the Schottky and Poole–Frenkel effects.