44227 research outputs found
Sort by
Accurate, Precise, and Verifiable Photoluminescence Efficiency of Colloidal Quantum Dots Sols by Photothermal Threshold Quantum Yield Analysis
No full textColloidal quantum dots (QDs) have become multipurpose luminophores that combine a broad excitation with a narrow emission spectrum. Applications in displays, lighting, or solar-energy conversion, however, require quantum dots that have a photoluminescent quantum yield (PLQY) approaching unity. This need makes the accurate, precise, and verifiable determination of the photoluminescence efficiency of QDs of utmost importance for the field. Here, we describe photothermal threshold quantum yield as a calorimetric method for measuring the PLQY of QDs in liquid dispersions. Taking the example of InP-based core/shell QDs, we detail the principles behind the analysis, and we benchmark results relative to the spectroscopic determination using an absolute PLQY measurement with an integrating sphere. We argue that the accuracy of the method for highly efficient emitters, and the simplicity of the data and the data analysis make photothermal threshold quantum yield well suited for certifying the photoluminescence efficiency of QDs.P.S. acknowledges VLAIO (O&O ReQLED2020) and FWOVlaanderen (12A9123N) for research funding. Z.H. acknowledges the FWO-Vlaanderen (research project G0B2921N), Ghent University (BOF-GOA 01G02124) and Catalisti (cSBO NaPoly) for research funding. S.M. and KV acknowledge the European Research Council (ERC, grant agreement 864625) and Hasselt University (BOF19OWB15)
Processing and optimizing polyhydroxyalkanoates: circular materials of the future for use as innovative food packaging material
No full text1. Polyhydroxyalkanoates are promising circular plastics 2. Nanocomposite materials for use as active packaging materials 3. Strategies to enhance PHA nanocomposite processing and properties 4. Safe use of biodegradable nanocomposite material
Parasites warning us on ecosystem changes. The case study of fish parasites in anthropogenically impacted Lake Victoria
No full textHow parasites are affected by global change is largely unknown, despite their ubiquity and crucial role for ecosystem
health in maintaining complexity and contributing to ecosystem robustness. Human-induced environmental changes
are expected to alter parasite abundance and host-parasite interactions (e.g. spillovers), but the direction of such
changes is unclear, as its consequences for ecosystem health. Lake Victoria, the youngest of the African Great Lakes,
is a biodiversity hotspot that experienced simultaneous drastic anthropogenic changes, the main being: Nile perch
invasions and eutrophication. We compared gill macroparasite communities of 13 cichlid fish species 20 years before
and after the onset of these anthropogenic perturbations, using historical and recent fish collections. We observed a
decline in parasite abundance, biodiversity indices, and co-infections. The host-parasite network rearranged, some
parasites disappeared from some host species and colonized few new ones, in a way that reduces ecosystem stability.
This highlights the need to preserve parasites and their ecosystem services in face of global change. We also
disentangled the cause of such changes, by comparing parasite communities between lake ecosystems similar and close
to Lake Victoria but differing in perturbation types. This space-for-time approach revealed that the observed changes
in parasite communities in Lake Victoria are not due to natural fluctuations, but rather result from the effect of both
studied perturbations. Since changes that have occurred in Lake Victoria are also occurring in other ecosystems, we
can use parasites as sentinel for ecosystem health, which might contribute to better strategies for linking conservation
and ecosystem health
The complex interplay between mechanical forces, tissue response and individual susceptibility to pressure ulcers
No full textObjective: The most recent edition of the International Clinical Practice Guideline for the Prevention and Treatment of Pressure Ulcers/Injuries was released in 2019. Shortly after, in 2020, the first edition of the SECURE Prevention expert panel report, focusing on device-related pressure ulcers/injuries, was published as a special issue in the Journal of Wound Care. A second edition followed in 2022. This article presents a comprehensive summary of the current understanding of the causes of pressure ulcers/injuries (PU/Is) as detailed in these globally recognised consensus documents. Method: The literature reviewed in this summary specifically addresses the impact of prolonged soft tissue deformations on the viability of cells and tissues in the context of PU/Is related to bodyweight or medical devices. Results: Prolonged soft tissue deformations initially result in cell death and tissue damage on a microscopic scale, potentially leading to development of clinical PU/Is overtime. That is, localised high tissue deformations or mechanical stress concentrations can cause microscopic damage within minutes, but it may take several hours of continued mechanical loading for this initial cell and tissue damage to become visible and clinically noticeable. Superficial tissue damage primarily stems from excessive shear loading on fragile or vulnerable skin. In contrast, deeper PU/Is, known as deep tissue injuries, typically arise from stress concentrations in soft tissues at body regions over sharp or curved bony prominences, or under stiff medical devices in prolonged contact with the skin. Conclusion: This review promotes deeper understanding of the pathophysiology of PU/Is, indicating that their primary prevention should focus on alleviating the exposure of cells and tissues to stress concentrations. This goal can be achieved either by reducing the intensity of stress concentrations in soft tissues, or by decreasing the exposure time of soft tissues to such stress concentrations. Declaration of interest: The author has no conflicts of interest
Organic Electrochemical Transistor Channel Materials: Copolymerization Versus Physical Mixing of Glycolated and Alkoxylated Polymers
No full textOrganic electrochemical transistors (OECTs) feature a polymer channel capable of conducting both ions and electronic charges. The choice of the channel material is critical for OECT performance. Many efforts have focused on improving performance via the chemical tunability of conjugated polymers - through backbone, side chain, and molar mass engineering - leading to useful design principles for accumulation-mode OECT materials. However, tuning the chemical structure of conjugated polymers often requires time-consuming optimization of the synthesis route. Meanwhile, variations in molar mass, dispersity, structural defects, and metal content present challenges when attempting to analyze the detailed effects of structural modifications, as multiple performance-determining factors are often (unintentionally) changed at the same time. Therefore, this study explores blended channel materials obtained by physically mixing glycolated and alkoxylated polymers in different ratios, and compares their OECT performance with the corresponding statistical copolymers. It is shown that mixing two well-performing materials creates blends that enable rational tuning of the transistor properties without compromising on performance. Thus, channels based on blends of alkoxylated and glycolated polymers hold promise for OECT technology with tailored response, as only two materials are needed to achieve any desired side chain ratio, simplifying the optimization of OECT characteristics.This project received funding from the European Union’s Horizon 2020 Research and Innovation Program under grant agreement no. 964677 (MITICS). W.M., K.V., L.B., J.V., and A.G. thank the FWO Vlaanderen for
financial support (WEAVE project G025922N and Ph.D. grants 1S70122N and 1S50820N). K.Z., N.B., and D.T. acknowledge the Swiss National Science Foundation (grant 200021E_205216) and the University of Bern for funding. We also thank O. Bardagot for helpful discussions on OECT measurements and data analysis. Use of the Stanford Synchrotron Radiation Light source, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515
Normative data for instrumented posturography: a systematic review and meta-analysis
No full textPostural control is a multisensory adaptive system performing predictive (anticipatory) and/or reactive (compensatory) actions, with varying degrees of accuracy, to maintain balance in a changing environmental context. Common instrumentation to evaluate balance includes static and dynamic force platforms; added sway-referenced perturbations on the dynamic platform constitute its main advantage. Clinical applications notwithstanding, normative data are needed for interpretation in clinical settings. Posturography norms are used to compare a reference group (healthy individuals) and a specific patient population. This work, to the best of our knowledge, represents the first attempt to synthesize the literature on normative data for computerized posturography using a combined mixed method. The search strategy resulted in the retrieval of 1,244 articles from PubMed, Web of Science, and Science Direct. After deduplication, 689 articles were screened based on title and abstract. One hundred and seven articles met the criteria after the first screening. In-depth, full-text screening resulted in the inclusion of 44 studies for the systematic review and 17 studies for the meta-analyses. The main findings of the systematic review are (1) extensive heterogeneity was found in methodological characteristics, (2) there was insufficient risk of bias mitigation, (3) the majority of tasks evaluated less than four components of the systems framework for postural control (SFPC), and (4) studies mostly used distance domain sway parameters and did not report the influence of other variables on postural sway. Based on the multilevel meta-analyses, females appeared to outperform males in eyes closed (EC) conditions significantly. Based on the network meta-analyses, we found that younger children swayed more than those aged between 8 and 14 years both in eyes open (EO) conditions and EC conditions significantly. The results also revealed a significant difference in sway between individuals of age range between 50 and 79 years old and younger individuals, with more instability observed in older participants both in EO conditions and in EC conditions. Thus, future studies need to ensure that enough information about participants is provided. Standardization of experimental conditions and sway parameters harmonization are still needed to ensure high-quality assessment (QA). Finally, evidence-based postural impairment management requires both age- and sex-related normative data. Systematic review registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023378144, identifier PROSPERO 2023 CRD42023378144.The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. AJ was funded by a PhD program under an Industrial Training by the Research (CIFRE) contract in partnership with the National Association Research-Technology (ANRT) and Virtualis SAS, grant number 2019/1807
Fast and efficient joint modelling of multivariate longitudinal data and time-to-event data with a pairwise-fitting approach
No full textIn empirical studies, multiple outcomes are often measured repeatedly over time, and interest frequently lies in studying the association between these longitudinal outcomes and a time-to-event outcome. Therefore, shared-parameter joint models for longitudinal and time-to-event outcomes have been developed. However, while such joint models in theory also allow for multiple longitudinal outcomes, they are often restricted to a limited number of outcomes due to computational complexity when fitting the models. To address this problem, we propose a new joint model, which is based on correlated instead of shared random effects, and for which a pairwise-modelling strategy can be used. In this approach, the longitudinal outcomes are modelled with (generalized) linear mixed models and the survival outcome with a Weibull proportional hazards frailty model. Instead of fitting the full joint model, this approach involves fitting all possible bivariate models, and inference is based on pseudo-likelihood theory. The main advantage of our approach is that there is no restriction on the number of longitudinally measured outcomes that are jointly modelled with the time-to-event outcome.The authors received no financial support for the research, authorship and/or publication of this article
Commentaar bij art. 496 oud BW
No full textAfdeling 3. ORGANISATIE VAN HET BEWIND 496. Iedere persoon voor wie geen rechterlijke beschermingsmaatregel bedoeld in artikel 492/1 werd genomen kan, ten overstaan van de vrederechter van zijn ver-blijfplaats of, bij gebrek daaraan, van zijn woonplaats of ten overstaan van een notaris een verklaring afleggen waarin hij zijn voorkeur te kennen geeft omtrent de aan te wijzen bewindvoerder of vertrouwenspersoon indien de vrederechter een rechterlijke beschermingsmaatregel zou bevelen. In dezelfde verklaring kunnen een aantal beginselen worden opgenomen die de bewindvoerder met een opdracht van vertegenwoordiging in acht moet nemen bij de uitoefening van zijn opdracht. Van deze verklaring wordt een authentieke akte opgesteld. De vrederechter met bijstand van de griffier kan zich op verzoek en op kosten van de verzoeker, zelfs buiten zijn kanton, naar diens verblijfplaats of woonplaats begeven om een verklaring op te nemen. Binnen vijftien dagen na het afleggen van voormelde verklaring laat de griffier of de notaris deze verklaring opnemen in een centraal register dat wordt bijge-houden door de Koninklijke Federatie van het Belgisch notariaat. De Koning bepaalt de nadere regels inzake oprichting, beheer en raadpleging van het centraal register. De Koning bepaalt welke overheden gratis toegang tot het centraal register hebben. De Koning bepaalt het tarief van de kosten voor de opneming van de verklaringen. […] De in het eerste lid bedoelde persoon kan op ieder moment op dezelfde wijze als bepaald in het eerste en tweede lid de verklaring herroepen en desgevallend een nieuwe voorkeur uitdrukken. Er wordt voorts gehandeld zoals bepaald in de vorige leden. De vrederechter of notaris voor wie de herroeping plaatsheeft, stelt de vrederechter of notaris voor wie de oorspronkelijke verklaring werd afgelegd, hiervan in kennis. Deze laatste vermeldt de herroeping op de gewijzigde akte. 496. Toute personne pour laquelle aucune mesure de protection judiciaire visée à l'article 492/1 n'a été prise peut déposer devant le juge de paix de sa résidence ou, à défaut, de son domicile ou devant un notaire une déclaration dans laquelle elle fait connaître sa préférence en ce qui con-cerne l'administrateur ou la personne de confiance à désigner si le juge de paix ordonnait une mesure de protection judiciaire. Cette même déclaration peut contenir plusieurs principes que l'administrateur chargé d'une mission de représentation doit respecter dans l'exercice de sa mission. Il est établi un acte authentique de cette déclaration. Le juge de paix assisté du greffier peut se rendre à la résidence ou au domicile du demandeur, même en dehors de son canton, à la de-mande et aux frais de ce dernier, afin d'enregistrer une déclaration. 91 Personen-en familierecht OPF-Afl. 105 (31 januari 2025