Nonlinear modal interactions in clamped-clamped mechanical resonators

A theoretical and experimental investigation is presented on the intermodal coupling between the flexural vibration modes of a single clamped-clamped beam. Nonlinear coupling allows an arbitrary flexural mode to be used as a self-detector for the amplitude of another mode, presenting a method to measure the energy stored in a specific resonance mode. Experimentally observed complex nonlinear dynamics of the coupled modes are quantitatively captured by a model which couples the modes via the beam extension; the same mechanism is responsible for the well-known Duffing nonlinearity in clamped-clamped beams.Comment: 5 pages, 3 figure

Fibre-reinforced polymer strengthening of substandard lap-spliced reinforced concrete members: A comprehensive survey

Externally bonded Fibre Reinforced Polymer (FRP) confinement is extensively used to improve the bond strength of substandard lap spliced steel bars embedded in reinforced concrete (RC) components. However, the test results from bond tests on such bond-deficient components are not fully conclusive, which is reflected in the few design guidelines available for FRP strengthening. For the first time, this article presents a comprehensive survey on FRP strengthening of substandard lap-spliced RC members, with emphasis on the adopted experimental methodologies and analytical approaches developed to assess the effectiveness of FRP in controlling bond-splitting failures. The main findings and shortcomings of previous investigations are critically discussed and further research needs are identified. This review contributes towards the harmonisation of testing procedures so as to facilitate the development of more accurate predictive models, thus leading to more cost-effective strengthening interventions

Noninfectious sternal wound inflammation after coronary artery bypass grafting in a patient with myelodysplastic syndrome: A no‐touch approach

Pyoderma gangrenosum (PG) is a rare, chronic inflammatory noninfectious dermatosis. It is associated with underlying systemic or hematological diseases such as myelodysplastic syndrome (MDS) and can be triggered after surgery. Recognition and diagnosis of PG can be difficult as it can mimic a wound infection. Misdiagnosis could lead to invasive procedures which worsen the disease and have possible disastrous aftermath. A 74‐year‐old male with a history of MDS presents with an atypical sternal wound inflammation. Diagnosis confirmed PG after skin biopsy. No surgical or invasive procedures were performed and the patient was treated on an outpatient basis with prednisolone, clobetasol cream, and cyclosporine. This case shows the importance of a rapid diagnosis of the disease. Awareness is required for the diagnosis of PG in a wound with pronounced livid borders, without improvement after antibiotic treatment or worsening after debridement. Rapid diagnosis and treatment reduce high healthcare costs, morbidity, and mortality

De zoekende ondernemer; Een studie naar het netwerken in de agrosector

Het doel van het project 'het ontwikkelen en toetsen van interventietrajecten om het ondernemerschap in de agrarische sector te versterken, met speciale aandacht voor de versterking van netwerkcompetenties' is in vier stappen uitgewerkt. Allereerst is een theoretische verkenning uitgevoerd rond ondernemerschap(scompetenties), strategisch management en het netwerken. Vervolgens zijn diepte-interviews gehouden en is een uitgebreide interventiestudie uitgevoerd. Ten slotte zijn de ervaringen bij de opzet en uitvoering èn de bevindingen bediscussieerd met vertegenwoordigers van adviesorganisaties en kennisinstellingen. The aim of the project 'the development and testing of intervention trajectories aimed at strengthening entrepreneurship in the agricultural sector, with special focus on strengthening networking competences' was developed in four steps. First of all, a theoretical study was conducted into entrepreneurship and entrepreneurial competences, strategic management and networking activities. This was followed by in-depth interviews and a detailed intervention study. Finally, the experiences in setting up and implementing the project as well as the findings were discussed with representatives of advisory organisations and educational institutions

Characterisation of the TBR1 interactome: variants associated with neurodevelopmental disorders disrupt novel protein interactions

TBR1 is a neuron-specific transcription factor involved in brain development and implicated in a neurodevelopmental disorder (NDD) combining features of autism spectrum disorder (ASD), intellectual disability (ID) and speech delay. TBR1 has been previously shown to interact with a small number of transcription factors and co-factors also involved in NDDs (including CASK, FOXP1/2/4 and BCL11A), suggesting that the wider TBR1 interactome may have a significant bearing on normal and abnormal brain development. Here we have identified approximately 250 putative TBR1-interaction partners by affinity purification coupled to mass spectrometry. As well as known TBR1-interactors such as CASK, the identified partners include transcription factors and chromatin modifiers, along with ASD- and ID-related proteins. Five interaction candidates were independently validated using bioluminescence resonance energy transfer assays. We went on to test the interaction of these candidates with TBR1 protein variants implicated in cases of NDD. The assays uncovered disturbed interactions for NDD-associated variants and identified two distinct protein-binding domains of TBR1 that have essential roles in protein–protein interaction

Design of simple synthetic RNA thermometers for temperature-controlled gene expression in Escherichia coli

RNA thermometers are thermosensors that regulate gene expression by temperature-induced changes in RNA conformation. Naturally occurring RNA thermometers exhibit complex secondary structures which are believed to undergo a series of gradual structural changes in response to temperature shifts. Here, we report the de novo design of considerably simpler RNA thermometers that provide useful RNA-only tools to regulate bacterial gene expression by a shift in the growth temperature. We show that a single small stem-loop structure containing the ribosome binding site is sufficient to construct synthetic RNA thermometers that work efficiently at physiological temperatures. Our data suggest that the thermometers function by a simple melting mechanism and thus provide minimum size on/off switches to experimentally induce or repress gene expression by temperature