3,516 research outputs found

    Business Value Is not only Dollars - Results from Case Study Research on Agile Software Projects

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    Business value is a key concept in agile software development. This paper presents results of a case study on how business value and its creation is perceived in the context of agile projects. Our overall conclusion is that the project participants almost never use an explicit and structured approach to guide the value creation throughout the project. Still, the application of agile methods in the studied cases leads to satisfied clients. An interesting result of the study represents the fact that the agile process of many projects differs significantly from what is described in the agile practitioners’ books as best practices. The key implication for research and practice is that we have an incentive to pursue the study of value creation in agile projects and to complement it by providing guidelines for better client’s involvement, as well as by developing structured methods that will enhance the value-creation in a project

    Graphene oxide sheets-based platform for induced pluripotent stem cells culture: toxicity, adherence, growth and application

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    It was prepared the graphene oxide (GO) sheets by suspension of GO in ultrapure deionized water or in Pluronic F-68 using a ultrasonicator bath. Total characterization of GO sheets was carried out. The results on suspension of GO in water showed excellent growth and cell adhesion. GO/Pluronic F-68 platform for the growth and adhesion of adipose-derived stem cells (ASCs) that exhibits excellent properties for these processes. GO in water suspension exhibited an inhibition of the cell growth over 5 mu g/mL In vivo study with GO suspended in water (100 g/mL) on Fisher 344 rats via i.p. administration showed low toxicity. Despite GO particle accumulates in the intraperitoneal cavity, this fact did not interfere with the final absorption of GO. The AST (aspartate aminotransferase) and ALT (alanine aminotransferase) levels (liver function) did not differ statistically in all experimental groups. Also, creatinine and urea levels (renal function) did not differ statistically in all experimental groups. Taking together, the data suggest the great potential of graphene oxide sheets as platform to ACSs, as well as, new material for treatment several urological diseases6174th International Conference on Safe Production and Use of Nanomaterials (Nanosafe

    Determination of electromagnetic medium from the Fresnel surface

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    We study Maxwell's equations on a 4-manifold where the electromagnetic medium is described by an antisymmetric (22)2\choose 2-tensor κ\kappa. In this setting, the Tamm-Rubilar tensor density determines a polynomial surface of fourth order in each cotangent space. This surface is called the Fresnel surface and acts as a generalisation of the light-cone determined by a Lorentz metric; the Fresnel surface parameterises electromagnetic wave-speed as a function of direction. Favaro and Bergamin have recently proven that if κ\kappa has only a principal part and if the Fresnel surface of κ\kappa coincides with the light cone for a Lorentz metric gg, then κ\kappa is proportional to the Hodge star operator of gg. That is, under additional assumptions, the Fresnel surface of κ\kappa determines the conformal class of κ\kappa. The purpose of this paper is twofold. First, we provide a new proof of this result using Gr\"obner bases. Second, we describe a number of cases where the Fresnel surface does not determine the conformal class of the original (22)2\choose 2-tensor κ\kappa. For example, if κ\kappa is invertible we show that κ\kappa and κ1\kappa^{-1} have the same Fresnel surfaces.Comment: 23 pages, 1 figur
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