In this paper, we will prove the following theorem, Let R be a ring with 1 having
a reverse derivation d ≠ 0 such that, for each x R, either d(x) = 0 or d(x) is
invertible in R, then R must be one of the following: (i) a division ring D, (ii) D 2 ,
the ring of 2×2 matrices over D, (iii) D[x]/(x ) 2
where char D = 2, d (D) = 0 and
d(x) = 1 + ax for some a in the center Z of D. Furthermore, if 2R ≠ 0 then R = D 2 is
possible if and only if D does not contain all quadratic extensions of Z, the center of
D.

this paper, we will prove the following theorem, Let R be a ring with 1 having
a reverse derivation d ≠ 0 such that, for each x R, either d(x) = 0 or d(x) is
invertible in R, then R must be one of the following: (i) a division ring D, (ii) D 2 ,
the ring of 2×2 matrices over D, (iii) D[x]/(x ) 2
where char D = 2, d (D) = 0 and
d(x) = 1 + ax for some a in the center Z of D. Furthermore, if 2R ≠ 0 then R = D 2 is
possible if and only if D does not contain all quadratic extensions of Z, the center of
D.

In this work, functionally graded materials were synthesized by centrifugal technique at different
volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T
= 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites
and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina
(Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength
occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value was
at 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the fu

Back ground: Hirschsprung`s disease is a common problem among pediatric population, many procedures had been implemented in the treatment with different results. In the last decades one stage transanal endorectal pullthrough (TEPT) had come into the stage as a minimal invasive choice for such condition with good results.
Objectives: To evaluate the feasibility and safety of TEPT procedure among pediatrics in a tertiary pediatric surgery center in Iraq.
Patients and Methods: A prospective study was conducted on 11 patients with Hirschsprung’s disease, attending Central Teaching Hospital of Pediatrics for the period from March 2007 till August 2014. Their ages were ranging from 1 month - 12 years. All cases had diverting colostomy

Background: perniosis is a common dermatological problem. Different modalities of treatment are available with conflicting results and no single effective therapy is universally accepted.
Objective: To evaluate the effectiveness of oral tadalafil and compare it with pentoxyfylline or prednisolone in treatment of perniosis
Patients and methods: This was a therapeutic comparative trial conducted in the department of Dermatology, Baghdad Teaching hospital, Baghdad, Iraq between November 2011 and March 2014.
Fifty eight patients with perniosis were enrolled in this study, and divided into 3 groups. Group (A) comprised 19 patients who received oral tadalafil (5 mg once daily); group (B) comprised 18 patients who received pentoxifylli

Currently, one of the topical areas of application of machine learning methods is the prediction of material characteristics. The aim of this work is to develop machine learning models for determining the rheological properties of polymers from experimental stress relaxation curves. The paper presents an overview of the main directions of metaheuristic approaches (local search, evolutionary algorithms) to solving combinatorial optimization problems. Metaheuristic algorithms for solving some important combinatorial optimization problems are described, with special emphasis on the construction of decision trees. A comparative analysis of algorithms for solving the regression problem in CatBoost Regressor has been carried out. The object of

The present work aimed to study the efficiency of nanofiltration (NF) and reverse osmosis (RO) process for treatment of heavy metals wastewater contains zinc. In this research, the salt of heavy metals were zinc chloride (ZnCl2) used as feed solution.Nanofiltration and reverse osmosis membranes are made from polyamide as spiral wound module. The parameters studied were: operating time (0 – 70 min), feed concentrations for zinc ions (10 – 300 mg/l), operating pressure (1 – 4 bar).The theoretical results showed, flux of water through membrane decline from 19 to 10.85 LMH with time. Flux decrease from 25.84 to 10.88 LMH with the increment of feed concentration. The raise of pressure, the flux increase for NF and RO membranes.The maximum

The purpose of this paper is to prove the following result : Let R be a 2-torsion free prime *-ring , U a square closed *-Lie ideal, and let T: RR be an additive mapping. Suppose that 3T(xyx) = T(x) y*x* + x*T(y)x* + x*y*T(x) and x*T(xy+yx)x* = x*T(y)x*2 + x*2T(y)x* holds for all pairs x, y  U , and T(u) U, for all uU, then T is a reverse *-centralizer.

     This study observed the formation of struvite crystals in wastewater using natural zeolite activated with Mg²⁺ ions. Mg²⁺ ions released from natural zeolite would react with PO₄^3- and NH₄⁺ ions from in wastewater to form struvite crystals. The results showed that at pH 8.5, the removal of PO₄^3- and NH₄⁺ ions was more effective using the modified zeolite than the natural zeolite. Adding 40 g/L Zeo-Mg (1) produced the best results, with PO4^3- (93.32%) and NH₄ (40%) adsorption. Meanwhile, 40g/L Zeo-Mg (2) adsorbed 81% PO₄^3- ions and 27.12% NH₄⁺ ions. The eqil

A new method presented in this work to detect the existence of hidden

data as a secret message in images. This method must be applyied only on images which have the same visible properties (similar in perspective) where the human eyes cannot detect the difference between them.

This method is based on Image Quality Metrics (Structural Contents

Metric), which means the comparison between the original images and stego images, and determines the size ofthe hidden data. We applied the method to four different images, we detect by this method the hidden data and  find exactly the same size of the hidden data.