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In this article we present a general approach not relying on item response theory models (non-IRT) to detect differential item functioning (DIF) in dichotomous items with presence of guessing. The proposed nonlinear regression (NLR) procedure for DIF detection is an extension of method based on logistic regression. As a non-IRT approach, NLR can be seen as a proxy of detection based on the three-parameter IRT model which is a standard tool in the study field. Hence, NLR fills a logical gap in DIF detection methodology and as such is important for educational purposes. Moreover, the advantages of the NLR procedure as well as comparison to other commonly used methods are demonstrated in a simulation study. A real data analysis is offered to demonstrate practical use of the method. [ABSTRACT FROM AUTHOR]

The solubilization of targeted compounds represents key criteria in the sophisticated field of medical chemistry but also in technical applications like scale removal. Especially, the simultaneous dissolution of two chemically different compounds remains challenging. Herein, macromolecular solubilizers are introduced for the simultaneous dissolution and encapsulation of poorly water‐soluble cholesterol and hydroxyapatite. The peptide‐based, amphiphilic block copolymers possess physicochemically disparate segments combined in one polymer chain as binding sites for hydrophobic as well as ionic materials. Small polymer libraries are synthesized and screened for structure–property relationships. Complementary analytical techniques suggest polymeric self‐assembly into spherical adaptive nanoparticles with the fundamental ability to passively absorb significant amounts of hydrophobic cholesterol up to 33 wt%. Furthermore, the additional incorporation of acidic domains enables the simultaneous dissolution of hydrophobic compounds and mineral phases such as hydroxyapatite. Ultimately, those nontoxic block copolymers can be used to solubilize and absorb other lipophilic and ionic compounds such as Sudan III dye and calcium ions. Such multifunctional nanomaterials have a wide range of direct application for simultaneous dissolution or delivery of hydrophobic molecules and cations resp. minerals for instance in the field of atherosclerosis. [ABSTRACT FROM AUTHOR]