Mixed micelles of the phospholipid dimyristoylphosphatidylcholine (DMPC) and bile salts of sodium deoxycholate (NaDC) were investigated by a combination of techniques, including time-resolved fluorescence quenching (TRFQ), electron spin resonance (ESR), viscometry, pulsed-gradient spin-echo NMR (PGSE-NMR), and surface tensiometry. Aggregation numbers, and bimolecular collision rate constants of guest molecules confined in the micelles (by TRFQ), interfacial hydration index and microviscosity, (by ESR), axial ratio (from solution viscosity), micelle self-diffusion coefficient (by PGSE-NMR), and the critical micelle concentrations (from surface tension) were determined for various molar compositions defined by the ratio R identical with [NaDC]/[DMPC] and concentrations ([NaDC]+[DMPC]). The data interpretation showed the micelles to be polydisperse rods. Aggregate properties depend on the ratio, R and reveal behavior unlike that in micelles of surfactants with aliphatic nonpolar chains. With increase in concentration from [NaDC] = 0.010 M to [NaDC] = 0.200 M, the hydration index and the aggregation number exhibit non-monotonic variations. Formulation of a polar shell model for cylindrical micelles yielded a set of nonlinear equations for the structural features of the micelle. The solutions give the microstructural description of the mixed micelle that includes the length, diameter, number of water molecules in the hydration shell, and the monomer organization in the micelle.

Grounded theory (GT) has established itself as a rigorous process that allows in-depth analysis. The popularity of GT demands that implementation process be made easy to understand and adopt especially for novice grounded theorists. This article, therefore, introduces an analytic instrument to enable grounded theorists to organize handling of data and coding in a sophisticated manner with productive results. The Ünlü-Qureshi instrument, an analytic tool for grounded theorists, comprises four steps: code, concept, category, and theme. Each step helps in understanding, interpreting, and organizing the data in a way that leads toward theory emerging from the data. The Ünlü-Qureshi instrument was used in two studies using GT: one where students’ feedback was examined and other where mentoring patterns were studied. Both studies found the Ünlü-Qureshi instrument a useful tool. This article explains the GT steps and implementation of Ünlü-Qureshi instrument for grounded theorists, especially novice researchers.

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The three Grounded Theory (GT hereafter) schools, Classic, Straussian, and Constructivist GT, differ from each other based on their paradigmatic perspectives. The major difference is in terms of the data analysis procedure. Common features exist among the three GT traditions such as constant comparison method, simultaneous data collection and analysis, memos, theoretical sensitivity, theoretical sampling, and theoretical saturation. Among these features, theoretical saturation acts as a key factor that initiates each coding stage of GT while ending the preceding one. This paper focuses on Theoretical Saturation in GT and evaluates how different GT paradigms approach the concept of Theoretical Saturation. Additionally, facilitating novice GT researchers, the paper suggests the Q-Ü Theoretical Saturation instrument to offer possible solutions to overcome the paradigm-related and practical challenges.

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