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Pattern formation driven by differential strain in constrained elastic systems is a common motif in many technological and biological systems. Here we introduce a biologically motivated case of elastic patterning that allows us to explore the conditions for the existence of local puckering and global wrinkling patterns: a soft growing composite ring adhered elastically to a constraining rigid ring. We explore how differential growth of the soft ring and the elastic resistance to shear and stretching deformations induced by soft adherence lead to a range of phenomena that include uniform aperture-like modes, localized puckers that are Nambu–Goldstone-like modes and global wrinkles in the system. Our analysis combines computer simulations of a discrete rod model with a nonlinear stability analysis of the differential equations in the continuum limit. We provide phase diagrams and scaling relations that reveal the nature and extent of the deformation patterns. Overall, our study reveals how geometry and mechanics conspire to yield a rich phenomenology that could serve as a guide to the design of programmable localized elastic deformations while being relevant for the mechanical basis of biological morphogenesis. [ABSTRACT FROM AUTHOR]

Dendritic spines are small membranous structures that protrude from the neuronal dendrite. Each spine contains a synaptic contact site that may connect its parent dendrite to the axons of neighboring neurons. Dendritic spines are markedly distinct in shape and size, and certain types of stimulation prompt spines to evolve, in fairly predictable fashion, from thin nascent morphologies to the mushroom-like shapes associated with mature spines. It is well established that the remodeling of spines is strongly dependent upon the actin cytoskeleton inside the spine. A general framework that details the precise role of actin in directing the transitions between the various spine shapes is lacking. We address this issue, and present a quantitative, model-based scenario for spine plasticity validated using realistic and physiologically relevant parameters. Our model points to a crucial role for the actin cytoskeleton. In the early stages of spine formation, the interplay between the elastic properties of the spine membrane and the protrusive forces generated in the actin cytoskeleton propels the incipient spine. In the maturation stage, actin remodeling in the form of the combined dynamics of branched and bundled actin is required to form mature, mushroom-like spines. Importantly, our model shows that constricting the spine-neck aids in the stabilization of mature spines, thus pointing to a role in stabilization and maintenance for additional factors such as ring-like F-actin structures. Taken together, our model provides unique insights into the fundamental role of actin remodeling and polymerization forces during spine formation and maturation. [ABSTRACT FROM AUTHOR]

ABSTRACT Currently used software process improvement methods such as the Capability Maturity Model Integration (CMMI) rely in their process assessments on information, which is gathered during interviews, in oral audit sessions, and from quality manuals and process standard reviews. Although valuable information about software processes can be gained in these assessments, the resulting data quality can be improved upon. This paper investigates the potential of process mining to support current software process assessment and improvement approaches. Based on an analysis of CMMI from a process mining perspective, particular CMMI model components are identified for which it is in principle possible to apply process mining techniques. Subsequently, criteria have been defined to select, with respect to these particular CMMI components, software processes for which process mining has an added value. These criteria have been applied in the selection of a particular 'minable' software process, that is, a change control process. Subsequently, the results of a case study from industrial practice, on the process mining of a change control board process, are used to illustrate that process mining can provide CMMI assessors with relevant information. This information reflects the actual or 'real' software processes in practice, and as such, it offers an excellent basis to support assessors in understanding the 'actual' software processes. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper describes an experimental approach towards the definition of a metric for integration test effort based on enterprise resource planning (ERP) system logs. By nature, ERP systems are complex. After implementing an ERP-system, it is typically subjected to many, and often concurrent, changes. On the one hand, these factors that cause the effort, which is to be invested in integration testing, become exceptionally hard to predict. On the other hand, the effect of invested integration test effort can seldom be determined for the same reasons. To show how aspects of effort can be distilled from the flow of changes, we propose a change stream reconstruction process based on SAP R/3 (SAP AG, Walldorf, Germany) system logs. Next, we introduce sampling methods yielding multivariate datasets, which bring the following results. The number of carriers of the change and their testing lead-time correlate moderately. The number of objects comprising the system's code and configuration, which have been touched during the change process, and lapsed testing lead-time are not correlated. Six independent cases are subjected to two distinct lines of investigation. [ABSTRACT FROM AUTHOR]

This paper considers the phenomenon of waiting lists in a healthcare setting, which is characterised by limitations on the national expenditure, to explore the potentials of an operations management perspective. A reference framework for waiting list management is described, distinguishing different levels of planning in healthcare--national, regional, hospital and process--that each contributes to the existence of waiting lists through managerial decision making. In addition, different underlying mechanisms in demand and supply are distinguished, which together explain the development of waiting lists. It is our contention that within this framework a series of situation specific models should be designed to support communication and decision making. This is illustrated by the modelling of the demand for cataract treatment in a regional setting in the south-eastern part of the Netherlands. An input-output model was developed to support decisions regarding waiting lists. The model projects the demand for treatment at a regional level and makes it possible to evaluate waiting list impacts for different scenarios to meet this demand. [ABSTRACT FROM AUTHOR]

BackgroundModern health care focuses on shared decision making (SDM) because of its positive effects on patient satisfaction, therapy compliance, and outcomes. Patients’ knowledge about their illness and available treatment options, gained through medical education, is one of the key drivers for SDM. Current patient education relies heavily on medical consultation and is known to be ineffective. ObjectiveThis study aimed to determine whether providing patients with information in a subdivided, categorized, and interactive manner via an educational app for smartphone or tablet might increase the knowledge of their illness. MethodsA surgeon-blinded randomized controlled trial was conducted with 213 patients who were referred to 1 of the 6 Dutch hospitals by their general practitioner owing to knee complaints that were indicative of knee osteoarthritis. An interactive app that, in addition to standard care, actively sends informative and pertinent content to patients about their illness on a daily basis by means of push notifications in the week before their consultation. The primary outcome was the level of perceived and actual knowledge that patients had about their knee complaints and the relevant treatment options after the intervention. ResultsIn total, 122 patients were enrolled in the control group and 91 in the intervention group. After the intervention, the level of actual knowledge (measured on a 0-36 scale) was 52% higher in the app group (26.4 vs 17.4, P

The article offers information on the report on Autosomal dominant polycystic kidney disease (ADPKD). Topics discussed include information on the characterization of the ADPKD by the presence of multiple cysts residing in the kidneys and liver; discussions on the study reveals that pharmacokinetic suitability of ciprofloxacin for treatment of hepatic cyst infections; and the information on the study on cyst infection, confirmed by cyst fluid culture for E. coli and Klebsiella pneumoniae.