Number theorists believe that primes play a central role in Number theory and that solving problems related to primes could lead to the resolution of many other unsolved conjectures, including the prime k-tuples conjecture. This paper aims to demonstrate the existence of this conjecture for admissible k-tuples in a positive proportion. The authors achieved this by refining the methods of “Goldston, Pintz and Yildirim” and “James Maynard” for studying bounded gaps between primes and prime k-tuples. These refinements enabled to overcome the previous limitations and restrictions and to show that for a positive proportion of admissible k-tuples, there is the existence of the prime k-tuples conjecture holding for each “k”. The sig

Throughout this paper S will be denote a monoids with zero. In this paper, we introduce the concept of En- prime subact, where a proper subact B of a right S- act As is called En- prime subact if for any endomorphism f of As and a As with f(a)S⊆ Bimplies that either a B or f(As) ⊆ B. The right S-act As is called En-prime if the zero subact of As is En-prime subact. Some various properties of En-prime subact are considered, and also we study some relationships between En-prime subact and some other concepts such as prime subact and maximal subact. 

      In this study, we prove that let N be a fixed positive integer and R be a semiprime -ring with extended centroid . Suppose that additive maps  such that  is onto,  satisfy one of the following conditions  belong to Г-N- generalized strong commutativity preserving for short; (Γ-N-GSCP) on R   belong to Г-N-anti-generalized strong commutativity preserving for short; (Γ-N-AGSCP)  Then there exists an element  and  additive maps  such that  is of the form  and   when condition (i) is satisfied, and     when condition (ii) is satisfied   

       Let R be a commutative ring with unity .M an R-Module. M is called coprime module     (dual notion of prime module) if ann M =ann M/N for every proper submodule N of M   In this paper we study coprime modules we give many basic properties of this concept. Also we give many characterization of it under certain of module.

Background: Use of magnetic resonance imaging (MRI) to calculate skeletal age is a novel idea. MRI provides excellent soft-tissue contrast and multiplanar cross-sectional imaging capability. It could be used as an alternative method of skeletal age determination.
Objectives: To study the value of MRI in estimating the age of healthy Iraqi adolescent males and to compare the obtained results with other countries records.
Population and methods: This cross sectional study was applied on 179 healthy adolescent males between the ages of 13 to18 years in MRI unit at radiology institute in medical city, Baghdad – Iraq. This study was carried out from November 2011 to December 2012. Magnetic resonance imaging of the left wrist was perfo

In this paper, we introduce and study the notion of the maximal ideal graph of a commutative ring with identity. Let R be a commutative ring with identity. The maximal ideal graph of R, denoted by MG(R), is the undirected graph with vertex set, the set of non-trivial ideals of R, where two vertices I₁ and I₂ are adjacent if I₁ I₂ and I₁+I₂ is a maximal ideal of R. We explore some of the properties and characterizations of the graph.

    We introduce in this paper the concept of approximaitly semi-prime submodules of unitary left -module  over a commutative ring  with identity as a generalization of a prime submodules and semi-prime submodules, also generalization of quasi-prime submodules and approximaitly prime submodules. Various basic properties of an approximaitly semi-prime submodules are discussed, where a proper submodule  of an -module  is called an approximaitly semi-prime submodule of  , if whenever , where ,  and , implies that . Furthermore the behaviors of approximaitly semi-prime submodule in some classes of modules are studied. On the other hand several characterizations of this concept are

            A spectrophotometric- reverse flow injection analysis (rFIA) method has been proposed for the   determination of Nitrazepam (NIT) in pure and pharmaceutical preparations. The method is based upon the coupling reaction of NIT with a new reagent O-Coumaric acid (OCA) in the presence of sodium periodate in an aqueous solution. The blue color product was measured at 632 nm. The variation (chemical and physical parameters) related with reverse flow system were estimated. The linearity was over the range 15 - 450 µg/mL of NIT with detection limits and limit of quantification of 3.425 and 11.417 µg mL^-1 NIT,respectively. The sample throughput of 28 samples

Background: Diabetes mellitus is a major risk factor for coronary artery disease, with a higher incidence of myocardial infarction and sudden death. Left ventricular dysfunction is difficult to diagnose and to differentiate into diastolic and systolic dysfunction on the basis of medical history, physical examination, electrocardiography (ECC) and chest radiography. Two-dimensional, M-mode, and Doppler echocardiography are excellent for diagnosing left ventricular dysfunction. M-mode echocardiography was used for diagnosing left ventricular systolic dysfunction, while Doppler echocardiography has become well accepted as a reliable, reproducible and practical noninvasive method for the diagnosis of left v