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Compression with the Juxta reduction Kit (medi) in patients undergoing a total knee arthroplasty

Neural Bidirectional Texture Function Compression and Rendering

The recent success of Machine Learning encouraged research using artificial neural networks (NNs) in computer graphics. A good example is the bidirectional texture function (BTF), a data-driven representation of surface materials that can encapsulate complex behaviors that would otherwise be too expensive to calculate for real-time applications, such as self-shadowing and interreflections. We propose two changes to the state-of-the-art using neural networks for BTFs, specifically NeuMIP. These changes, suggested by recent work in neural scene representation and rendering, aim to improve baseline quality, memory footprint, and performance. We conduct an ablation study to evaluate the impact of each change. We test both synthetic and real data, and provide a working implementation within the Mitsuba 2 rendering framework. Our results show that our method outperforms the baseline in all these metrics and that neural BTF is part of the broader field of neural scene representation. Project website: https://traverse-research.github.io/NeuBTF/.

Experimental characterization of the axial behavior of traditional masonry wall metal tie connections in cavity walls

In recent years, the number of human-induced earthquakes in Groningen, a large gas field in the north of the Netherlands, has increased. The majority of the buildings are built by using unreinforced masonry (URM), most of which consists of cavity (i.e. two-leaf) walls, and were not designed to withstand earthquakes. Efforts to define, test and standardize the metal ties, which do play an important role, are valuable also from the wider construction industry point of view. The presented study exhibits findings on the behavior of the metal tie connections between the masonry leaves often used in Dutch construction practice, but also elsewhere around the world. An experimental campaign has been carried out at Delft University of Technology to provide a complete characterization of the axial behavior of traditional connections in cavity walls. A large number of variations was considered in this research: two embedment lengths, four pre-compression levels, two different tie geometries, and five different testing protocols, including monotonic and cyclic loading. The experimental results showed that the capacity of the connection was strongly influenced by the embedment length and the geometry of the tie, whereas the applied pre-compression and the loading rate did not have a significant influence.

Memes and the reactionary totemism of the theft of joy

(This is part III of a series of essays on meme theory, all published on this site. Part I is called They Say That We Can’t Meme: Politics of Idea Compression. Part II is entitled Rude Awakening: Memes as Dialectical Images)

Numerical modelling of cavity wall metal ties

The assessment of the out-of-plane response of unreinforced masonry (URM) buildings with cavity walls has been a popular topic in regions such as Central and Northern Europe, Australia, New Zealand, China and several other countries.Cavity walls are particularly vulnerable as the out-of-plane capacity of each individual leaf is significantly smaller than the one of a solid wall. In the Netherlands, cavity walls are characterized by an inner load-bearing leaf of calcium silicate bricks, and by an outer veneer of clay bricks that has only aesthetic and insulation functions. The two leaves are typically connected by means of metallic ties. This paper utilizes the results of an experimental campaign conducted by the authors to calibrate a hysteretic model that represents the axial cyclic response of cavity wall tie connections. The proposednumerical model uses zero-length elements implemented in OpenSees with the Pinching4 constitutive model to account for the compression-tension cyclic behaviour of the ties. The numerical model is able to capture important aspects of the tie response such as the strength degradation, the unloading stiffness degradation and the pinching behaviour. The numerical modelling approach in this paper can be easily adopted by practitioner engineers who aim to model the wall ties more accurately when assessing the structures against earthquakes.

Conventional chest physical therapy for obstructive lung disease

Chest physical therapy (CPT) is a widely used intervention for patients with airway diseases. The main goal is to facilitate secretion transport and thereby decrease secretion retention in the airways. Historically, conventional CPT has consisted of a combination of forced expirations (directed cough or huff), postural drainage, percussion, and/or shaking. CPT improves mucus transport, but it is not entirely clear which groups of patients benefit from which CPT modalities. In general, the patients who benefit most from CPT are those with airways disease and objective signs of secretion retention (eg, persistent rhonchi or decreased breath sounds) or subjective signs of difficulty expectorating sputum, and with progression of disease that might be due to secretion retention (eg, recurrent exacerbations, infections, or a fast decline in pulmonary function). The most effective and important part of conventional CPT is directed cough. The other components of conventional CPT add little if any benefit and should not be used routinely. Alternative airway clearance modalities (eg, high-frequency chest wall compression, vibratory positive expiratory pressure, and exercise) are not proven to be more effective than conventional CPT and usually add little benefit to conventional CPT. Only if cough and huff are insufficiently effective should other CPT modalities be considered. The choice between the CPT alternatives mainly depends on patient preference and the individual patient's response to treatment.