166 research outputs found
Heron Visualisation Engine. Visualisation and dissemination of semantic cultural heritage data
Over the past two decades, there has been a proliferation of software to create great 3D models of archaeological sites and objects, and there has been plenty of thought and discussion on data models for finds. The results of those efforts have been made public through institutional websites and specific portals, but now, a further step is necessary: the cultural heritage data and (meta)data need to be taken into the semantic web. The Heritage Online Visualisation Engine (further: Heron VE) provides tools for documenting, visualising and disseminating the semantic relations between sites, objects, documentation and narratives. Heron VE is scalable: it can be used to tell the story of a particular archaeological complex, but it can also illustrate relations between sites and objects which are widely separated in both time and space. With Heron VE, dissemination of (meta)data can take many different forms: Heron VE contains modules for presenting and reporting on data, but it can also be used to provide data only, for example in several XML-formats or in N-triples. The designer of Heron VE has 25 years of experience with cultural heritage data in the field of archaeology, museums and libraries and has been working on the structured dissemination of cultural heritage data, first in the semantic web and now within the framework of linked data. This paper will illustrate the journey towards Heron VE, including considerations regarding the adoption, adaptation or rejection of existing data models and ontologies. It will also contain examples. These will mainly be based on data regarding sites of former castles and stately homes in the Netherlands, but it will become very clear that the Heron VE can be applied to many different cultural heritage datasets, including those regarding ancient urban areas
Een eenzaam staatsman. Dirk de Geer, 1870 - 1960
Biografie van politicus Dirk de
Geer. Hij behoorde met Colijn en Ruijs de Beerenbrouck tot de
toonaangevende Nederlandse politici in het interbellum. Behalve Kamerlid
was hij minister van financiën en minister-president. In die laatste
functie besloot hij om in 1940 na de inval door de Duitse leger uit te
wijken met zijn kabinet naar Londen. Daar dwong koningin Wilhelmina hem
tot aftreden en keerde hij terug naar Nederland. Vervolgens schreef hij
een brochure waarin hij pleitte voor samenwerking met het Duitse regime.
Hiervoor werd hij in 1947 strafrechtelijk verooordeeld.LEI Universiteit LeidenTrias Europea: de verhoudingen tussen de overheidsmachten in de EU en de lidstaten in een bewegend constitutioneel landscha
Characterization of the starch-acting MaAmyB enzyme from Microbacterium aurum B8.A representing the novel subfamily GH13_42 with an unusual, multi-domain organization
The bacterium Microbacterium aurum strain B8.A degrades granular starches, using the multi-domain MaAmyA α-amylase to initiate granule degradation through pore formation. This paper reports the characterization of the M. aurum B8.A MaAmyB enzyme, a second starch-acting enzyme with multiple FNIII and CBM25 domains. MaAmyB was characterized as an α-glucan 1,4-α-maltohexaosidase with the ability to subsequently hydrolyze maltohexaose to maltose through the release of glucose. MaAmyB also displays exo-activity with a double blocked PNPG7 substrate, releasing PNP. In M. aurum B8.A, MaAmyB may contribute to degradation of starch granules by rapidly hydrolyzing the helical and linear starch chains that become exposed after pore formation by MaAmyA. Bioinformatics analysis showed that MaAmyB represents a novel GH13 subfamily, designated GH13_42, currently with 165 members, all in Gram-positive soil dwelling bacteria, mostly Streptomyces. All members have an unusually large catalytic domain (AB-regions), due to three insertions compared to established α-amylases, and an aberrant C-region, which has only 30% identity to established GH13 C-regions. Most GH13_42 members have three N-terminal domains (2 CBM25 and 1 FNIII). This is unusual as starch binding domains are commonly found at the C-termini of α-amylases. The evolution of the multi-domain M. aurum B8.A MaAmyA and MaAmyB enzymes is discussed
Monitoring LVAD parameters to detect flow-and power-impacting complications: A proof-of-concept
The number of patients on left ventricular assist device (LVAD) support increases due to the growing number of patients with end-stage heart failure and the limited number of donor hearts. Despite improving survival rates, patients frequently suffer from adverse events such as cardiac arrythmia and major bleeding. Telemonitoring is a potentially powerful tool to early detect deteriorations and may further improve outcome after LVAD implantation. Hence, we developed a personalized algorithm to remotely monitor HeartMate3 (HM3) pump parameters aiming to early detect unscheduled admissions due to cardiac arrythmia or major bleeding. The source code of the algorithm made publicly available. The algorithm was optimized and tested retrospectively using HM3 power and flow data of 120 patients, including 29 admissions due to cardiac arrythmia and 14 admissions due to major bleeding. Using a true alarm window of 14 days prior to the admission date, the algorithm detected 59% and 79% of unscheduled admissions due to cardiac arrythmia and major bleeding, respectively, with a false alarm rate of 2%. The proposed algorithm showed that the personalized algorithm is a viable approach to early identify cardiac arrythmia and major bleeding by monitoring HM3 pump parameters. External validation is needed and integration with other clinical parameters could potentially improve the predictive value. In addition, the algorithm can be further enhanced using continuous data
Circadian rhythms in pump parameters of patients on contemporary left ventricular assist device support
Background: Algorithms to monitor pump parameters are needed to further improve outcomes after left ventricular assist device (LVAD) implantation. Previous research showed a restored circadian rhythm in pump parameters in patients on HeartWare (HVAD) support. Circadian patterns in HeartMate3 (HM3) were not studied before, but this is important for the development of LVAD monitoring algorithms. Hence, we aimed to describe circadian patterns in HM3 parameters and their relation to patterns in heart rate (HR). Methods: 18 HM3 patients were included in this study. HM3 data were retrieved at a high frequency (one sample per 1 or 2 h) for 1–2 weeks. HR was measured using a wearable biosensor. To study overall patterns in HM3 parameters and HR, a heatmap was created. A 24-h cosine was fitted on power and HR separately. The relationship between the amplitude of the fitted cosines of power and HR was calculated using Spearman correlation. Results: A lower between patient variability was found in power compared with flow and PI. 83% of the patients showed a significant circadian rhythmicity in power (p < 0.001–0.04), with a clear morning increase. All patients showed significant circadian rhythmicity in HR (p < 0.001–0.02). The amplitudes of the circadian rhythm in power and HR were not correlated (Spearman correlation of 0.32, p = 0.19). Conclusions: A circadian rhythm of pump parameters is present in the majority of HM3 patients. Higher frequency pump parameter data should be collected, to enable early detection of complications in the future development of predictive algorithms
Dilemmas concerning heart procurement in controlled donation after circulatory death
With an expanding population at risk for heart failure and the resulting increase in patients admitted to the waiting list for heart transplantation, the demand of viable organs exceeds the supply of suitable donor hearts. Use of hearts after circulatory death has reduced this deficit. Two primary techniques for heart procurement in circulatory death donors have been described: direct procurement and perfusion and thoraco-abdominal normothermic regional perfusion. While the former has been accepted as an option for heart procurement in circulatory death donors, the latter technique has raised some ethical questions in relation to the dead donor rule. In this paper we discuss the current dilemmas regarding these heart procurement protocols in circulatory death donors.</p
Circadian rhythms in pump parameters of patients on contemporary left ventricular assist device support
Aspergillus niger genome-wide analysis reveals a large number of novel alpha-glucan acting enzymes with unexpected expression profiles
The filamentous ascomycete Aspergillus niger is well known for its ability to produce a large variety of enzymes for the degradation of plant polysaccharide material. A major carbon and energy source for this soil fungus is starch, which can be degraded by the concerted action of α-amylase, glucoamylase and α-glucosidase enzymes, members of the glycoside hydrolase (GH) families 13, 15 and 31, respectively. In this study we have combined analysis of the genome sequence of A. niger CBS 513.88 with microarray experiments to identify novel enzymes from these families and to predict their physiological functions. We have identified 17 previously unknown family GH13, 15 and 31 enzymes in the A. niger genome, all of which have orthologues in other aspergilli. Only two of the newly identified enzymes, a putative α-glucosidase (AgdB) and an α-amylase (AmyC), were predicted to play a role in starch degradation. The expression of the majority of the genes identified was not induced by maltose as carbon source, and not dependent on the presence of AmyR, the transcriptional regulator for starch degrading enzymes. The possible physiological functions of the other predicted family GH13, GH15 and GH31 enzymes, including intracellular enzymes and cell wall associated proteins, in alternative α-glucan modifying processes are discussed
Mixed Reality in Modern Surgical and Interventional Practice: Narrative Review of the Literature
BACKGROUND
Mixed reality (MR) and its potential applications have gained increasing interest within the medical community over the recent years. The ability to integrate virtual objects into a real-world environment within a single video-see-through display is a topic that sparks imagination. Given these characteristics, MR could facilitate preoperative and preinterventional planning, provide intraoperative and intrainterventional guidance, and aid in education and training, thereby improving the skills and merits of surgeons and residents alike.
OBJECTIVE
In this narrative review, we provide a broad overview of the different applications of MR within the entire spectrum of surgical and interventional practice and elucidate on potential future directions.
METHODS
A targeted literature search within the PubMed, Embase, and Cochrane databases was performed regarding the application of MR within surgical and interventional practice. Studies were included if they met the criteria for technological readiness level 5, and as such, had to be validated in a relevant environment.
RESULTS
A total of 57 studies were included and divided into studies regarding preoperative and interventional planning, intraoperative and interventional guidance, as well as training and education.
CONCLUSIONS
The overall experience with MR is positive. The main benefits of MR seem to be related to improved efficiency. Limitations primarily seem to be related to constraints associated with head-mounted display. Future directions should be aimed at improving head-mounted display technology as well as incorporation of MR within surgical microscopes, robots, and design of trials to prove superiority
A Systematic Comparison Identifies an ATP-Based Viability Assay as Most Suitable Read-Out for Drug Screening in Glioma Stem-Like Cells
Serum-free culture methods for patient-derived primary glioma cultures, selecting for glioma stem-like cells (GSCs), are becoming the gold standard in neurooncology research. These GSCs can be implemented in drug screens to detect patient-specific responses, potentially bridging the translational gap to personalized medicine. Since numerous compounds are available, a rapid and reliable readout for drug efficacies is required. This can be done using approaches that measure viability, confluency, cytotoxicity, or apoptosis. To determine which assay is best suitable for drug screening, 10 different assays were systematically tested on established glioma cell lines and validated on a panel of GSCs. General applicability was assessed using distinct treatment modalities, being temozolomide, radiation, rapamycin, and the oncolytic adenovirus Delta24-RGD. The apoptosis and cytotoxicity assays did not unequivocally detect responses and were excluded from further testing. The NADH- and ATP-based viability assays revealed comparable readout for all treatments; however, the latter had smaller standard deviations and direct readout. Importantly, drugs that interfere with cell metabolism require alternative techniques such as confluency monitoring to accurately measure treatment effects. Taken together, our data suggest that the combination of ATP luminescence assays with confluency monitoring provides the most specific and reproducible readout for drug screening on primary GSCs
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