Cell contraction induces long-ranged stress stiffening in the extracellular matrix

Animal cells in tissues are supported by biopolymer matrices, which typically exhibit highly nonlinear mechanical properties. While the linear elasticity of the matrix can significantly impact cell mechanics and functionality, it remains largely unknown how cells, in turn, affect the nonlinear mechanics of their surrounding matrix. Here we show that living contractile cells are able to generate a massive stiffness gradient in three distinct 3D extracellular matrix model systems: collagen, fibrin, and Matrigel. We decipher this remarkable behavior by introducing Nonlinear Stress Inference Microscopy (NSIM), a novel technique to infer stress fields in a 3D matrix from nonlinear microrheology measurement with optical tweezers. Using NSIM and simulations, we reveal a long-ranged propagation of cell-generated stresses resulting from local filament buckling. This slow decay of stress gives rise to the large spatial extent of the observed cell-induced matrix stiffness gradient, which could form a mechanism for mechanical communication between cells

Context-aware and automatic configuration of mobile devices in cloud-enabled ubiquitous computing

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s00779-013-0698-3. Copyright @ Springer-Verlag London 2013.Context-sensitive (or aware) applications have, in recent years, moved from the realm of possibilities to that of ubiquity. One exciting research area that is still very much in the realm of possibilities is that of cloud computing, and in this paper, we present our work, which explores the overlap of these two research areas. Accordingly, this paper explores the notion of cross-source integration of cloud-based, context-aware information in ubiquitous computing through a developed prototypical solution. Moreover, the described solution incorporates remote and automatic configuration of Android smartphones and advances the research area of context-aware information by harvesting information from several sources to build a rich foundation on which algorithms for context-aware computation can be based. Evaluation results show the viability of integrating and tailoring contextual information to provide users with timely, relevant and adapted application behaviour and content

Protocol for Audiological Surveillance of Children at Risk for Permanent Hearing Loss

This document addresses procedures for the audiological surveillance of hearing of infants and young children at risk for late onset or progressive permanent hearing loss (PHL). It is closely linked with the Ontario Infant Hearing Program (IHP) Protocol for Universal Newborn Hearing Screening Auditory Brainstem Response Assessment (ABRA) Protocol, and the IHP protocol for Audiometric Assessment for Children Aged 6 to 60 Months with respect to risk indicators, hearing screening technology applied, screening bypass, and audiological assessment procedures

Everolimus as first line therapy for pancreatic neuroendocrine tumours: current knowledge and future perspectives

urpose Everolimus has been shown to be effective for advanced pancreatic neuroendocrine tumours (pNETs), but its positioning in the therapeutic algorithm for pNETs is matter of debate. Methods With the aim to shed light on this point, we performed an up-to-date critical review taking into account the results of both retrospective and prospective published studies, and the recommendations of international guidelines. In addition, we performed an extensive search on the Clinical Trial Registries databases worldwide, to gather information on the ongoing clinical trials related to this specific topic. Results We identified eight retrospective published studies, two prospective published studies, and five registered clinical trials. Moreover, we analyzed the content of four wide-spread international guidelines. Conclusions Our critical review confirms the lack of high-quality data to recommend everolimus as the first line therapy for pNETs. The ongoing clinical trials reported in this review will hopefully help clinicians, in the near future, to better evaluate the role of everolimus as the first line therapy for pNETs. However, at the moment, there is already enough evidence to recommend everolimus as the first line therapy for patients with symptomatic malignant unresectable insulin-secreting pNETs, to control the endocrine syndrome regardless of tumour growth