Good Applications for Crummy Entity Linkers? The Case of Corpus Selection in Digital Humanities

Over the last decade we have made great progress in entity linking (EL) systems, but performance may vary depending on the context and, arguably, there are even principled limitations preventing a "perfect" EL system. This also suggests that there may be applications for which current "imperfect" EL is already very useful, and makes finding the "right" application as important as building the "right" EL system. We investigate the Digital Humanities use case, where scholars spend a considerable amount of time selecting relevant source texts. We developed WideNet; a semantically-enhanced search tool which leverages the strengths of (imperfect) EL without getting in the way of its expert users. We evaluate this tool in two historical case-studies aiming to collect a set of references to historical periods in parliamentary debates from the last two decades; the first targeted the Dutch Golden Age, and the second World War II. The case-studies conclude with a critical reflection on the utility of WideNet for this kind of research, after which we outline how such a real-world application can help to improve EL technology in general.Comment: Accepted for presentation at SEMANTiCS '1

Unsupervised out-of-distribution detection for safer robotically-guided retinal microsurgery

Purpose: A fundamental problem in designing safe machine learning systems is identifying when samples presented to a deployed model differ from those observed at training time. Detecting so-called out-of-distribution (OoD) samples is crucial in safety-critical applications such as robotically-guided retinal microsurgery, where distances between the instrument and the retina are derived from sequences of 1D images that are acquired by an instrument-integrated optical coherence tomography (iiOCT) probe. Methods: This work investigates the feasibility of using an OoD detector to identify when images from the iiOCT probe are inappropriate for subsequent machine learning-based distance estimation. We show how a simple OoD detector based on the Mahalanobis distance can successfully reject corrupted samples coming from real-world ex-vivo porcine eyes. Results: Our results demonstrate that the proposed approach can successfully detect OoD samples and help maintain the performance of the downstream task within reasonable levels. MahaAD outperformed a supervised approach trained on the same kind of corruptions and achieved the best performance in detecting OoD cases from a collection of iiOCT samples with real-world corruptions. Conclusion: The results indicate that detecting corrupted iiOCT data through OoD detection is feasible and does not need prior knowledge of possible corruptions. Consequently, MahaAD could aid in ensuring patient safety during robotically-guided microsurgery by preventing deployed prediction models from estimating distances that put the patient at risk.Comment: Accepted at IPCAI 202

Control of an air pressure actuated disposable bioreactor for cultivating heart valves

Tissue-engineered heart valves, cultured from human stem cells, are a possible alternative for replacing failing aortic heart valves, where nowadays biological and mechanical heart valves are used. Growing and conditioning is done by mechanically stimulating the tissue in a bioreactor. The disposable injection molded bioreactor [24] uses flexible membranes and steering valves to mimic a physiological heart cycle. In this work, an air pressure actuation control system for this bioreactor is designed. One membrane is position controlled to achieve a desired flow through the heart valve, while another membrane controls the aortic pressure. A third actuator controls a steering valve used to impose a resistance on the flow back to the first membrane, in order to control the heart valve closing pressure. Due to the repetitive character of the setpoints, iterative learning controllers are implemented. A high position tracking performance is achieved and pressure setpoints are mimicked successfully, but the main focus is on preventing large pressure oscillations and other events that could be damaging for the tissue heart valve. The control system allows full adjustability of operating conditions needed for the growing, conditioning and testing phases

Synthesis of Tetrapeptides Containing Dehydroalanine, Dehydrophenylalanine and Oxazole as Building Blocks for Construction of Foldamers and Bioinspired Catalysts

The incorporation of dehydroamino acid or fragments of oxazole into peptide chain is accompanied by a distorted three-dimensional structure and additionally enables the introduction of non-typical side-chain substituents. Thus, such compounds could be building blocks for obtaining novel foldamers and/or artificial enzymes (artzymes). In this paper, effective synthetic procedures leading to such building blocks—tetrapeptides containing glycyldehydroalanine, glycyldehydrophenylalanine, and glycyloxazole subunits—are described. Peptides containing serine were used as substrates for their conversion into peptides containing dehydroalanine and aminomethyloxazole-4-carboxylic acid while considering possible requirements for the introduction of these fragments into long-chain peptides at the last steps of synthesis

Ex-vivo experiments with a microrobotic surgical system for vitreo-retinal surgery

Purpose:Developments in vitreo-retinal eye surgery are limited by human capabilities. To improve current vitreo-retinal surgical procedures and to enable new procedures, a robotic system has been developed, extending human capabilities. Methods:A compact, lightweight, easy to setup robotic master-slave system has been realized to perform vitreo-retinal eye surgery (Slave see Figure 1, Master see Figure 2). The system’s reach covers the major part of the vitreous cavity (up to the peripheral region). A combination of advanced mechanical and control design facilitates high accuracy

Assessing the Added Value of Global Mobility Versus Local Experience: A Case Study

Although the data for this study were collected some time ago, the recent publication of the Erasmus Impact Study (European Commission, 2014) has made it worthwhile reflecting on results from this research to add to the body of knowledge on the impact of study abroad on the development of a young individual (see also Brandenburg et al, this volume)

The effect of cryotherapy on postural stabilization assessed by standardized horizontal perturbations of a movable platform

Background: Cryotherapy is a frequently used therapy in the acute treatment of sports injuries, although it has possible negative effects on dynamic postural stabilization. Research question: What is the effect of cryotherapy on the postural stabilization assessed by imposed platform perturbations? Methods: Twenty-four healthy participants (15 male, 9 female) performed 2 test sessions (before and after cryotherapy) consisting of 4 trials each. Each trial included 30 s single leg stance (SLS) on both legs and 4 testing blocks (2 for each leg) of 30 s for the dynamic testing. A single testing block comprised 4 perturbations. After the first session, cryotherapy was applied to the right leg by placing it in ice water at a temperature between 10 °C and 12 ° for 20 min. Outcome measures: We assessed the Center of Pressure speed (CoPs) and the mean force variation for both static and dynamic tests. Additionally, the Time To Stability (TTS) was calculated for the perturbations. Results: In the static trials there was an interaction between leg and session present for the mean force variation (p = 0.01) with a large η2 of 0.24, which shows higher variation of vertical force after application of the cryotherapy on the right leg. During the dynamic trials we found an interaction between leg and session for the TTS suggesting increase of the TTS due to the cryotherapy (p = 0.04), with a large η2 of 0.17. No interaction effect was present for the CoPs in the mediolateral and anteroposterior direction (p = 0.62 and p = 0.12, respectively). Significance: Cryotherapy applied to the lower extremity results in a worse postural stabilization when assessed by platform perturbations. This might be the result of an altered balance strategy, due to impaired proprioception from the affected body part. More research is needed to examine the duration of this effect. Level of evidence: Level 3, associative stud