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Background The criteria for the diagnosis of kidney disease outlined in the Kidney Disease: Improving Global Outcomes guidelines are based on a patient’s current, historical, and baseline data. The diagnosis of acute kidney injury, chronic kidney disease, and acute-on-chronic kidney disease requires previous measurements of creatinine, back-calculation, and the interpretation of several laboratory values over a certain period. Diagnoses may be hindered by unclear definitions of the individual creatinine baseline and rough ranges of normal values that are set without adjusting for age, ethnicity, comorbidities, and treatment. The classification of correct diagnoses and sufficient staging improves coding, data quality, reimbursement, the choice of therapeutic approach, and a patient’s outcome. Objective In this study, we aim to apply a data-driven approach to assign diagnoses of acute, chronic, and acute-on-chronic kidney diseases with the help of a complex rule engine. Methods Real-time and retrospective data from the hospital’s clinical data warehouse of inpatient and outpatient cases treated between 2014 and 2019 were used. Delta serum creatinine, baseline values, and admission and discharge data were analyzed. A Kidney Disease: Improving Global Outcomes–based SQL algorithm applied specific diagnosis-based International Classification of Diseases (ICD) codes to inpatient stays. Text mining on discharge documentation was also conducted to measure the effects on diagnosis. Results We show that this approach yielded an increased number of diagnoses (4491 cases in 2014 vs 11,124 cases of ICD-coded kidney disease and injury in 2019) and higher precision in documentation and coding. The percentage of unspecific ICD N19-coded diagnoses of N19 codes generated dropped from 19.71% (1544/7833) in 2016 to 4.38% (416/9501) in 2019. The percentage of specific ICD N18-coded diagnoses of N19 codes generated increased from 50.1% (3924/7833) in 2016 to 62.04% (5894/9501) in 2019. Conclusions Our data-driven method supports the process and reliability of diagnosis and staging and improves the quality of documentation and data. Measuring patient outcomes will be the next step in this project.

As opposed to the recent tendency in Responsible Research and Innovation and in some approaches of Technology Assessment (like Vision Assessment) to reduce the role of socio-technical visions and s...

Most of the clinical outcome studies dealing with ACL repair are from the developer’s perspective. It is a fact that these developer-initiated studies tend to interpret the results rather in favour than against their developed technique or product. Hence, it was the purpose of the present independent investigator-initiated study to investigate the clinical and radiological outcomes as well as failure rate of patients who underwent an ACL suture using dynamic intraligamentary stabilisation device in a specialised independent knee clinic. A retrospective study was performed on prospectively collected data of 26 patients (28 ± 9 years, range 18–50 years; male/female = 17:9) who underwent biologically augmented ACL suture using dynamic intraligamentary stabilisation. Mean time from ACL injury was 15 ± 5 days (range 4–25 days). In addition, in seven (27%) patients a medial meniscus refixation and in four (15%) patients a lateral meniscus refixation was done for associated meniscal lesions. All patients were clinically and radiologically followed up at 6 weeks, 3 and 12 months after ACL surgery using the Tegner and Lysholm score as well as IKDC score. Adverse events such as ACL failure, arthrofibrosis, pain > 3 on a visual analogue scale as well as the need and type of revision surgery were noted. Four patients (15%) suffered from an ACL retear due to another adequate trauma during follow-up time. In six patients (23%), an arthrofibrosis (extension deficit of > 10° or flexion deficit > 20°) was noted. In five of those six patients, an arthroscopic arthrolysis was performed. Three patients also complained about pain VAS > 3. In nine (35%) patients, superfluous ACL scar tissue and the DIS device including the polyethylene suture and the DIS screw were removed, and in another two (8%) patients, the DIS screw only was removed. In two patients, a partial meniscectomy was performed due to a non-healed meniscal suture. The median Tegner score was 8 (range 6–10) before injury and 7 (range 3–10) at last follow-up (p

Summary: To safeguard runaway reactions in industrial scale, qualified methods have to be used. While mechanical safety devices are usually installed, their design may be problematic as the runaway kinetics must be known. This may not be the case for many processes due to the required flexibility and possible unanticipated deviations from recipes. It is shown that runaway kinetics can be very fast and can lead to high conversions. Therefore, a method is proposed that does not depend on kinetics but limits the amounts of unreacted monomer in the reactor by monitoring the conversion and by quantitatively determining the hazardous potential. If a potential violation is observed, feeds to the reactor are interrupted.

Recent years have seen an increasing interest in materiality in social research. Some might say that materiality is now back on the agenda of social research. The challenges of bringing materiality back have spurred lively debates about material agency, most of which, however, are leveled at the largely dematerialized theories of the social in the social sciences, for example, in material culture studies (Appadurai 1986; Miller 1998) as well as science and technology studies (Latour 1988; Law/Mol 1995). Since the turn of the century, a marked shift towards the material has emerged (cf. Hicks 2010), ranging from questions concerning nature (Grundmann/Stehr 2000) and everyday objects (Molotch 2003; Costall/Dreier 2006; Miller 2010) to issues of cultural theory (Reckwitz 2002), post-phenomenology (Verbeek 2005), ethnography (Henare et al. 2007), distributed cognition (Hutchins 1995), and materiality in general (Dant 2005; Miller 2005; Knappett/Malafouris 2008). A perspective on materiality is now being developed in diverse fields such as archaeology (Meskell 2005), economic sociology (Pinch/Swedberg 2008), political science (Bennett 2010; Coole/Frost 2010), and organization studies (Carlile et al. 2013). Yet the status of the material remains debated in the evolving fields of various “new” materialisms (cf. Lemke 2015).

The extraction and display of iso-surfaces is a standard method for the visualization of volume data sets. In this paper we present a novel approach that utilizes a hierarchy on both the input and the output data. For the generation of a coarse base mesh, we construct a hierarchy of volumes and extract an iso-surface from the coarsest resolution with a standard Marching Cubes algorithm. We additionally apply a simple mesh decimation algorithm to improve the shape of the triangles. We iteratively fit this mesh to the iso-surface at the finer volume levels. To be able to reconstruct fine detail of the iso-surface we thereby adaptively subdivide the mesh. To evenly distribute the vertices of the triangle mesh over the iso-surface and generate a triangle mesh with evenly shaped triangles, we have integrated a mesh smoothing algorithm into the fitting process. The advantage of this approach is that it generates a mesh with subdivision connectivity which can be utilized by several multiresolution algorithms such as compression and progressive transmission. As applications of our method we show how to reconstruct the surface of archeological artifacts and the reconstruction of the brain surface for the simulation of the brain shift phenomenon.

The implementation of direct search schemes for the design of multi-level diffractive optical elements is investigated. In particular, simulated annealing with an estimated temperature is shown to yield improvements in iteration time over simple simulated annealing. A cost function for the formation of greylevel diffraction patterns is suggested. An efficient method of finding an appropriate initial temperature for simulated annealing is presented.

Excimer lasers are well known for their ability to machine features on the micron scale. Recently, they have been used to fabricate diffractive optical elements (DOEs). These elements are patterns of pixels machined to the depth required, in order that a reconstructed pattern is formed in the image plane when the DOE is illuminated by a coherent source. The patterns are designed using computer phase retrieval code. These designs are used to create XY co-ordinate data files for conversion to machining routines where the pixels are machined individually. The laser used is an ArF excimer operating at 193 nm. We describe research undertaken on the fabrication and testing of some typical DOEs. The measurements include efficiency of reconstruction as well as the measurements of profile and surface roughness. The work compares the reconstruction results with the topographical measurements made on the DOE for 2, 4 and 8 phase-level designs. Newly developed simulation code was used to generate reconstructions without machining imperfections.

We report the fabrication and characterization of wavelength-scale diffractive optical elements etched directly on the surface of red (660 nm) vertical-cavity surface-emitting lasers. The structures were fabricated by focused ion beam etching. Linear and two-dimensional (2-D) grating configurations were investigated. Each showed excellent suppression of the zeroth-order diffracted beam. Compared to the power from an unetched laser, /spl sim/22% of the emission was coupled into the first order for linear gratings and 12% for the 2-D structures. Polarization was independent of grating orientation for grating pitches as small as 1/spl lambda/. Threshold current increases of 35%-40% were measured.

Background: Diffusion tensor imaging provides information about the location of white matter tracts within the human brain. For neurosurgery, this imaging technique is of major interest in order to minimize the risk of postoperative neurological deficits. In preoperative planning, fiber tracking algorithms based on streamline propagation are used in order to reconstruct major fiber tracts. The resulting streamline bundles approximate the course of the underlying white matter structures and indicate their shape and location in 3 dimensions as well as the spatial relation with respect to surrounding anatomy. However, for intraoperative application in combination with the neuronavigation system, these streamline representations are not adequate. Hulls encompassing the streamline bundles are necessary, since the boundary curves of hulls can be superimposed on the operating room (OR) microscope view for guidance in neurosurgery. Methods: In this work, we present a novel hull approach which is based on rasterization and isosurface extraction, combined with surface filtering techniques. The advantages of this approach are its robustness and the possibility to control the tightness of wrapping. Results: The approach makes it possible to generate precise hulls for different tract systems, which can be used as a basis for intraoperative visualization in the OR microscope. Distance measurements further confirm the accuracy of the hulls.

Diffusion tensor imaging provides information about structure and location of white matter tracts within the human brain which is of particular interest for neurosurgery. The reconstruction of neuronal structures from diffusion tensor data is commonly solved by tracking algorithms based on streamline propagation. These approaches generate streamline bundles that approximate the course of neuronal fibers. For medical application, a 3D representation of streamline bundles provides valuable information for pre-operative planning. However, for intra-operative visualization, surfaces wrapping eloquent structures are required for integration into the OR microscope. In order to provide hulls tightly encompassing the neuronal structures obtained from fiber tracking, we propose an approach based on tetrahedralization. This technique reuses the sampling points derived from fiber tracking and therefore provides precise hulls which serve as basis for intra-operative visualization.

We present the fabrication of phase only diffractive optical elements (DOEs) by contact prints using a novel technique. Phase only DOEs consist of a transparent slide with a surface profile that modulates the phase of an incident laser beam in the desired manner. This surface profile can be exploited to split or to shape the laser beam. In our process a Perspex sheet (PMMA) is exposed through a chrome-on-quartz mask that carries the DOE pattern. The UV light used in the exposure is generated by an ArF excimer laser (l=193nm). The high energy radiation causes photomodification and the phase pattern of the DOE is transferred to the PMMA. While the primary investigations concentrate on binary DOEs, which require one exposure only, we have also attempted to produce multilevel designs which need mask alignment and tighter control of the exposure. At the moment, we study the capability of the method to produce relatively large structures but it might also be possible to use it to manufacture finer structures.

We present a straightforward method to design multilevel phase-only diffractive optical elements with a locally improved signal-to-noise ratio in the reconstruction. The method is generally applicable to all unidirectional design schemes, such as direct search, simulated annealing, or genetic optimization. As the shape and the location of the desired low noise areas are supplied by a bit map file the method allows for the design of basically any two-dimensional low noise area. The improvement in the signal-to-noise ratio that may be achieved is considerable but also entails reduced diffraction efficiency. The suggested method is applied to different beam-splitter design examples. All examples are calculated with the scalar diffraction approximation in the far field.

We report on the design of small multilevel diffractive elements. The specific design problems that arise due to the limited size are discussed and it is shown that direct search and simulated annealing are appropriate tools to find a good solution. However, good convergence is only guaranteed if the algorithms are properly initialised.

Recently, viewpoint resolution methods which make conflicts productive have gained popularity in requirements engineering for organizational information systems. However, when extending such methods beyond organizational boundaries to social networks, sociological research indicates that a delicate balance of trust in individuals, confidence in the network as a whole, and watchful distrust becomes a key success factor. We capture these relationships in the so-called TCD (Trust-Confidence-Distrust) approach and demonstrate how this approach can be supported by a dynamic requirements engineering environment that combines the structural analysis of strategic dependencies and rationales, with the interaction between planning, tracing, and communicative action. An example drawn from an ongoing case study in entrepreneurship networks illustrates our approach.

In this paper we present a novel approach to iso-surface extraction which is based on a multiresolution volume data representation and hierarchically approximates the iso-surface with a semi-regular mesh. After having generated a hierarchy of volumes, we extract the iso-surface from the coarsest resolution with a standard Marching Cubes algorithm, apply a simple mesh decimation strategy to improve the shape of the triangles, and use the result as a base mesh. Then we iteratively fit the mesh to the iso-surface at the finer volume levels, thereby subdividing it adaptively in order to be able to correctly reconstruct local features. We also take care of generating an even vertex distribution over the iso-surface so that the final result consists of triangles with good aspect ratio. The advantage of this approach as opposed to the standard method of extracting the iso-surface from the finest resolution with Marching Cubes is that it generates a mesh with subdivision connectivity which can be utilized by several multiresolution algorithms. As an application of our method we show how to reconstruct the surface of archaeological items.