By the Von Neumann regular graph of R, we mean the graph that its vertices are all elements of R such that there is an edge between vertices x,y if and only if x+y is a von Neumann regular element of R, denoted by G_Vnr (R). For a commutative ring R with unity, x in R is called Von Neumann regular if there exists x in R such that a=a2 x. We denote the set of Von Neumann regular elements by V nr...

THE classical cataract section, either by a von Graefe knife or by a keratome and scissors, is essentially a section in which the cornea is sliced (Fig. 1). An enormous number of techniques has been developed which incorporate this slicing section; these usually involve direct suturing either of the cornea after its section, or of the corneo-scleral margin with or without a flap to cover the in...

DAVIEL (1753) described the first satisfactory method of cataract extraction before the Academie Royale de Chirurgie in 1752. He opened the eye with an instrument similar to the modern keratome and enlarged the incision with scissors. This method gradually displaced the ancient practice of couching until von Graefe described his cataract knife for making the incision in 1865. Von Graefe's catar...

die direktreduktion von eisenerzen zu eisenschwamm mittels erdgas wird iiberall dort verwendet wo einmal die notwendtigen rohstoffe und besonders der metallurgische koks zu wirtschaftlischen bedingungen fehlen. andereseirs wiederum miissen erdgasrerven in geniigenden mengen und qualitat zu verfugung stehen, urn die direktredution mit gutem wirkungsgrad durchfuhren zu konnen. in dieser arbeit wi...

NOTWITHSTANDING the vast literature, a complete and satisfactory definition of the clinical picture of amblyopia in strabismus has not yet been produced, and some symptoms are often confused with those of other forms of functional amblyopia. Bangerter (1953) and many other authors embrace in the term " amblyopia ex anopsia" the amblyopia observed in anisometropia, in high ametropia, and in nyst...

We study topological von Neumann regularity and principal von Neumann regularity of Banach algebras. Our main objective is comparing these two types of Banach algebras and some other known Banach algebras with one another. In particular, we show that the class of topologically von Neumann regular Banach algebras contains all $C^*$-algebras, group algebras of compact abelian groups and ...

Abstract Background and Aims:‎ Von Willebrand disease is a bleeding disorder caused by quantitative or functional defects in von Willebrand factor. The disease is found in up to 1 percent of the population. The most common symptom is mucocutaneous bleeding. Recently, studies conducted on healthy people showed that the H817Q mutation that previously known to cause von Willebrand...