University of Johannesburg

About: University of Johannesburg is a education organization based out in Johannesburg, South Africa. It is known for research contribution in the topics: Population & Tourism. The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.

A critical review of resilience theory and its relevance for social work

Abstract: As resilience theory gains traction as a theoretical framework for research in social work, it is important to engage with it critically. This article provides a critical review of resilience theory, drawing on an array of key authors, dating back fifty years. The review addresses three aspects of resilience theory: its definition, the construction of adversity and outcomes, and the nature and scope of resilience processes. The relevance of resilience theory for social work in South Africa is evaluated according to three criteria: the research questions it generates, its contribution to indigenous knowledge and decolonisation, and its contribution to social development

A multi-crystal method for extracting obscured crystallographic states from conventionally uninterpretable electron density.

Abstract: In macromolecular crystallography, the rigorous detection of changed states (for example, ligand binding) is difficult unless signal is strong. Ambiguous (‘weak’ or ‘noisy’) density is experimentally common, since molecular states are generally only fractionally present in the crystal. Existing methodologies focus on generating maximally accurate maps whereby minor states become discernible; in practice, such map interpretation is disappointingly subjective, time-consuming and methodologically unsound. Here we report the PanDDA method, which automatically reveals clear electron density for the changed state—even from inaccurate maps—by subtracting a proportion of the confounding ‘ground state’; changed states are objectively identified from statistical analysis of density distributions. The method is completely general, implying new best practice for all changed-state studies, including the routine collection of multiple ground-state crystals. More generally, these results demonstrate: the incompleteness of atomic models; that single data sets contain insufficient information to model them fully; and that accuracy requires further map-deconvolution approaches. Building a ligand into a weak region of an electron density map of a protein is a subjective process. Here, the authors present a new method to obtain a clear electron density for a bound ligand based on multi-crystal experiments and 3D background correction.