Type IV pili are ubiquitous bacterial motors that power surface motility. In peritrichously piliated species, it is unclear how multiple pili are coordinated to generate movement with directional persistence. Here we use a combined theoretical and experimental approach to test the hypothesis that multiple pili of Neisseria gonorrhoeae are coordinated through a tug-of-war. Based on force-dependent unbinding rates and pilus retraction speeds measured at the level of single pili, we build a tug-of-war model. Whereas the one-dimensional model robustly predicts persistent movement, the two-dimensional model requires a mechanism of directional memory provided by re-elongation of fully retracted pili and pilus bundling. Experimentally, we confirm memory in the form of bursts of pilus retractions. Bursts are seen even with bundling suppressed, indicating re-elongation from stable core complexes as the key mechanism of directional memory. Directional memory increases the surface range explored by motile bacteria and likely facilitates surface colonization.

Many organizations are currently combining information technology outsourcing strategies with agile software development practices. The resulting agile global outsourced software development (AGOSD) projects involve joint virtual client vendor teams that apply agile development methods for delivering software, and are specifically challenging in terms of appropriate communication. Therefore, our study provides insights on this topic by evaluating agile communication practices for the usage within AGOSD projects. Our study (1) empirically identifies formerly unknown agile communication practices and (2) provides a practical relevance ranking of communication practices for the usage within AGOSD projects. With our results, we shed light on the as-of-yet under-researched topic of communication practices within AGOSD projects and therefore provide important knowledge for both theory and practice.

Software development is increasingly heading in the direction of combining agile software development practices and outsourcing software development to external vendors worldwide. The resulting agile global outsourced software development (AGOSD) projects are characterized by applying agile methods to distributed environments, which results in several problems for collaboration and coordination. Specifically, communication between the project participants has been found to be a major challenge in distributed environment. Therefore, our study investigates the problem of improving communication in distributed settings by identifying suitable communication practices for usage within AGOSD projects. Based on an extensive literature review, our study (1) provides an overview of adequate practices for usage in AGOSD and (2) points out differences to traditional communication practices of agile software development (ASD) projects used in collocated, non-distributed environments. research question guides our study: "How do communication practices for agile software development differ from communication practices for usage within agile global outsourced software development projects?"To answer our research question, we conducted a structured and comparative literature review on communication practices within ASD and AGOSD projects based on the guidelines of Webster and Watson [15] and Levy [16]. We analyzed the existing literature on both ASD and AGOSD projects and identified a total set of 42 communication practices for usage within both ASD and AGOSD. After identifying and analyzing the practices, we conducted

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The outsourcing of information technology to external providers has been a phenomenon for organizations around the world since decades. The main reasons for this trend are, for example, cost reductions through scaling, the temporary inclusion of specific skills in the own organization as well as the joint development of innovative solutions with an external partner. The client organization ''RetBa,'' a major private insurance company, was facing serious quality and performance issues in the delivery of the workplace services. Hence, in 2005 they decided for an outsourcing solution aiming at moving the responsibility for managing IT workplace services for over 50,000 seats worldwide to the external service provider ''EuTu.'' Over the years, the outsourcing project faced several problems due to the lack of performance and delayed delivery of services by the service provider EuTu. To solve these quality issues and avoid further failures, in 2011 RetBa appointed Scaleit Consulting, a third-party advisor. Scaleit Consulting had the responsibility to identify the causes for these issues, revise the workplace strategy, and support RetBa in the communication with the service provider.