In this paper we give characterizations of essential left ideals of a C*-algebra A in terms of their properties as operator A-modules. Conversely, we seek C*-algebraic characterizations of those ideals J in A such that A is an essential extension of J in various categories of operator modules. In the case of two-sided ideals, we prove that all the above concepts coincide. We obtain results, ana...

Background and Objectives: Listeria monocytogenes is an emerging foodborne pathogen which may be transmitted through meat and dairy products to humans. In this study, effects of Cuminum cyminum essential oil (CCEO) and Biarum carduchcorum water extract (BCWE) and a combination of the two compounds on growth of L. monocytogenes and physicochemical, textural and sensory properties of lambs were i...

Jaw morphogenesis depends on the growth of Meckel's cartilage during embryogenesis. However, the cell types and signals that promote chondrocyte proliferation for Meckel's cartilage growth are poorly defined. Here we show that neural crest cells (NCCs) and their derivatives provide an essential source of the vascular endothelial growth factor (VEGF) to enhance jaw vascularization and stabilize ...

The study assessed the perceived effectiveness of agricultural extension methods used to disseminate improved technologies to rice farmers in kogi state, Nigeria. The specific objectives were to describe the socio – economic characteristics of the rice farmers, to assessed farmers level of contact with extension agents, perceived level of competence of extension agents to perform agricultural e...

The purpose of this study was to assess the process of extension program development in Iranian Agricultural Extension System (IAES). The research instrument was a structural questionnaire with close-ended questions which its validity and reliability was confirmed by using expert panel and Cranach’s alpha test, respectively. The target population of this research included all extension managers...

The limited audio bandwidth of narrowband telephone speech degrades the speech quality. This paper proposes a method that extends the bandwidth of telephone speech to the frequency range 0–300 Hz. The lowest harmonics of voiced speech are generated using sinusoidal synthesis. The energy in the extension band is estimated from spectral features using a Gaussian mixture model. The amplitudes and ...