Needle Tip Force Estimation using an OCT Fiber and a Fused convGRU-CNN Architecture

Needle insertion is common during minimally invasive interventions such as biopsy or brachytherapy. During soft tissue needle insertion, forces acting at the needle tip cause tissue deformation and needle deflection. Accurate needle tip force measurement provides information on needle-tissue interaction and helps detecting and compensating potential misplacement. For this purpose we introduce an image-based needle tip force estimation method using an optical fiber imaging the deformation of an epoxy layer below the needle tip over time. For calibration and force estimation, we introduce a novel deep learning-based fused convolutional GRU-CNN model which effectively exploits the spatio-temporal data structure. The needle is easy to manufacture and our model achieves a mean absolute error of 1.76 +- 1.5 mN with a cross-correlation coefficient of 0.9996, clearly outperforming other methods. We test needles with different materials to demonstrate that the approach can be adapted for different sensitivities and force ranges. Furthermore, we validate our approach in an ex-vivo prostate needle insertion scenario.Comment: Accepted for Publication at MICCAI 201

Heterozygous Loss-of-Function Mutations in DLL4 Cause Adams-Oliver Syndrome.

Adams-Oliver syndrome (AOS) is a rare developmental disorder characterized by the presence of aplasia cutis congenita (ACC) of the scalp vertex and terminal limb-reduction defects. Cardiovascular anomalies are also frequently observed. Mutations in five genes have been identified as a cause for AOS prior to this report. Mutations in EOGT and DOCK6 cause autosomal-recessive AOS, whereas mutations in ARHGAP31, RBPJ, and NOTCH1 lead to autosomal-dominant AOS. Because RBPJ, NOTCH1, and EOGT are involved in NOTCH signaling, we hypothesized that mutations in other genes involved in this pathway might also be implicated in AOS pathogenesis. Using a candidate-gene-based approach, we prioritized DLL4, a critical NOTCH ligand, due to its essential role in vascular development in the context of cardiovascular features in AOS-affected individuals. Targeted resequencing of the DLL4 gene with a custom enrichment panel in 89 independent families resulted in the identification of seven mutations. A defect in DLL4 was also detected in two families via whole-exome or genome sequencing. In total, nine heterozygous mutations in DLL4 were identified, including two nonsense and seven missense variants, the latter encompassing four mutations that replace or create cysteine residues, which are most likely critical for maintaining structural integrity of the protein. Affected individuals with DLL4 mutations present with variable clinical expression with no emerging genotype-phenotype correlations. Our findings demonstrate that DLL4 mutations are an additional cause of autosomal-dominant AOS or isolated ACC and provide further evidence for a key role of NOTCH signaling in the etiology of this disorder

Inrichtingsplan Rijnwaardense Uiterwaarden: ruimte voor water en natuur bij Lobith

Grootschalige, riviergebonden natuurontwikkeling wordt in dit uiterwaarden-inrichtingsplan, dat onderdeel is van het (natuur)ontwikkelingsgebied De Gelderse Poort, gecombineerd met een veilige verwerking van hoogwaterafvoeren van de Rijn volgens de nieuwe aangescherpte eisen, waardoor dit plan zowel ruimte voor water als natuur schept

Cloud photogrammetry with dense stereo for fisheye cameras

We present a novel approach for dense 3-D cloud reconstruction above an area of 10 × 10 km2 using two hemispheric sky imagers with fisheye lenses in a stereo setup. We examine an epipolar rectification model designed for fisheye cameras, which allows the use of efficient out-of-the-box dense matching algorithms designed for classical pinhole-type cameras to search for correspondence information at every pixel. The resulting dense point cloud allows to recover a detailed and more complete cloud morphology compared to previous approaches that employed sparse feature-based stereo or assumed geometric constraints on the cloud field. Our approach is very efficient and can be fully automated. From the obtained 3-D shapes, cloud dynamics, size, motion, type and spacing can be derived, and used for radiation closure under cloudy conditions, for example. Fisheye lenses follow a different projection function than classical pinhole-type cameras and provide a large field of view with a single image. However, the computation of dense 3-D information is more complicated and standard implementations for dense 3-D stereo reconstruction cannot be easily applied. Together with an appropriate camera calibration, which includes internal camera geometry, global position and orientation of the stereo camera pair, we use the correspondence information from the stereo matching for dense 3-D stereo reconstruction of clouds located around the cameras. We implement and evaluate the proposed approach using real world data and present two case studies. In the first case, we validate the quality and accuracy of the method by comparing the stereo reconstruction of a stratocumulus layer with reflectivity observations measured by a cloud radar and the cloud-base height estimated from a Lidar-ceilometer. The second case analyzes a rapid cumulus evolution in the presence of strong wind shear

Temporariness in architectural regeneration

The previous chapters have considered regeneration as a long term investment in an area through securing the future of buildings and places of architectural and communal significance. This chapter expounds the temporal dimension of regeneration and specifically focuses on short term or time bound interventions, considering their longer term implications for architectural regeneration in the context of the economic and social sustainability of places. Temporary structures have always been a fixture of urban and rural places, allowing spaces to be used for different functions, such as weekly markets or seasonal festivals. In rural areas temporary structures provide accommodation for seasonal agricultural workers, while entire towns are temporarily constructed to house pilgrims (Mehrotra and Vera 2015). In many parts of the world, temporary street vendors contribute to diversification of the retail offer and activate public spaces in the urban realm. There are also a host of other temporary activities that combine the need for an activity or use with a space that is permanently or temporarily redundant and vacant. These types of temporary interventions, some of which are trendily referred to as ‘pop-ups’ are emerging as a recognised component in the process of urban regeneration in the UK and across Europe (Bishop and Williams 2012; St Hill 2015). Pop-up architecture has become a regular thematic focus of design events, including the Venice Architecture Biennale since 2016. The trend is epitomised by images of re-purposed shipping containers, street food outlets and other functions that are prefixed with the word ‘pop-up’ (St Hill 2015). Often initiated by grass roots movements and/or young entrepreneurs, pop-ups generally involve the temporary use of a redundant space for a commercial, semi-commercial or charitable/community function. Temporary interventions come in multitudes of size, shape and duration and can be characterised by their function, type of space they occupy, intended purpose, instigators or duration and longevity. Temporary, locally initiated (and sourced) interventions are often viewed as a commitment to a locality. From an urbanism perspective, they highlight the dynamic nature of the built environment and its accompanying social fabric, where change and innovation are inseparably incorporated into everyday rhythms of daily life. Temporary interventions are being actively encouraged as part of urban regeneration in the spirit of co-creation, a shared activity of place making between planners and users (Fernandez 2015). Nonetheless, temporary activities, especially those with commercial purpose, can spearhead new opportunities but also represent conditions of precarity. While the flexible nature of a temporary venture can support the development of new products and services and test their viability, temporality can also be linked to the hand-to-mouth nature of the less permanent business model. The purpose of this chapter is to examine the characteristics and implications of a growing trend of temporary and short term approaches being adopted in architectural regeneration. In doing so the chapter will explore the condition of temporariness and its implications for the urban environment, evaluate the roles various actors take on in the processes of temporary urbanism, and reflect on the physical, socio-economic, political and cultural implications in the context of architectural regeneration

Static species distribution models in the marine realm: The case of baleen whales in the Southern Ocean

Aim Information on the spatio-temporal distribution of marine species is essential for developing proactive management strategies. However, sufficient information is seldom available at large spatial scales, particularly in polar areas. The Southern Ocean (SO) represents a critical habitat for various species, particularly migratory baleen whales. Still, the SO’s remoteness and sea ice coverage disallow obtaining sufficient information on baleen whale distribution and niche preference. Here, we used presence-only species distribution models to predict the circumantarctic habitat suitability of baleen whales and identify important predictors affecting their distribution. Location The Southern Ocean (SO). Methods We used Maxent to model habitat suitability for Antarctic minke, Antarctic blue, fin and humpback whales. Our models employ extensive circumantarctic data and carefully prepared predictors describing the SO’s environment and two spatial sampling bias correction options. Species-specific spatial-block cross-validation was used to optimize model complexity and for spatially independent model evaluation. Results Model performance was high on cross-validation, with generally little predicted uncertainty. The most important predictors were derived from sea ice, particularly seasonal mean and variability of sea ice concentration and distance to the sea ice edge. Main conclusions Our models support the usefulness of presence-only models as a cost-effective tool in the marine realm, particularly for studying the migratory whales’ distribution. However, we found discrepancies between our results and (within) results of similar studies, mainly due to using different species data quality and quantity, different study area extent and methodological reasons. We further highlight the limitations of implementing static distribution models in the highly dynamic marine realm. Dynamic models, which relate species information to environmental conditions contemporaneous to species occurrences, can predict near-real-time habitat suitability, necessary for dynamic management. Nevertheless, obtaining sufficient species and environmental predictors at high spatio-temporal resolution, necessary for dynamic models, can be challenging from polar regions