Showing papers by "University of Antwerp published in 2022"

Global maps of soil temperature

Abstract: Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

Notes on the role of metapragmatic awareness in language use

Abstract: Against the background of a general theory of pragmatics, reflections are formulated on the central role of metapragmatic awareness as a specific manifestation of salience, the status of processes of meaning generation in language use in relation to the cognitive apparatus. First the notions of metalanguage and metapragmatics, as used in linguistics, are discussed. Then metalinguistic and metapragmatic phenomena are presented as reflections of metapragmatic awareness. Two ways in which indicators of metapragmatic awareness function in language use are distinguished: Their functioning as anchoring devices locating linguistic form in relation to context, and their functioning as signals of the language users’ reflexive interpretations of the activities they are engaged in. Finally, some social implications of metapragmatic functioning are discussed, in particular in relation to language ideologies and identity construction.

The European clinical research response to optimise treatment of patients with COVID-19: lessons learned, future perspective, and recommendations

Abstract: Clinicians have worked feverishly to treat patients with COVID-19 while also carrying out clinical research studies. We discuss how the clinical research community responded to the pandemic in Europe, what lessons were learned, and provide recommendations for future clinical research response during pandemics. We focused on two platform trials: RECOVERY and REMAP-CAP. Both trials were able to enrol patients very rapidly during the beginning of the pandemic because of pre-established structures and procedures, and because they share simple execution and flexibility to adjust when evidence emergences. However, contracting, regulatory hurdles, and competition with (often inadequately designed or underpowered) national trials was a major challenge in several EU countries. We recommend the creation of structures and partnerships that facilitate prioritisation of clinical research, simplification of clinical trial delivery, development of digital models and procedures for data collection and sharing, development of a mechanism to rapidly leverage pandemic funding and to connect EU funding with national funding, and investment in clinical trial networks, platform trials, and master protocols. Finally, the future pandemic clinical research response of the EU should be embedded in the global response. We believe that globally connected clinical trial networks will be essential to respond more effectively to future infectious diseases outbreaks.

On the road again! An economic and environmental break-even and hotspot analysis of reclaimed asphalt pavement and rejuvenators

Abstract: Using reclaimed asphalt pavement (RAP) can help the asphalt industry to lessen its environmental and economic impact. Although literature shows that rejuvenators are needed for high RAP rates, limited information is known about the economic and environmental impact of rejuvenators. The first objective of this research was to determine the relative service life (SL) to break even economically and environmentally when using RAP and rejuvenators. If 40% asphalt binder replacement (ABR) is considered as the benchmark for surface layers, the SL without recycling should be 27% longer to result in economic and environmental benefits. Adding a rejuvenator to 40% ABR has a limited effect on the economic impact. Conversely, when adding a rejuvenator to the benchmark, the SL should increase by 9% (SMA 10 mix) or 21% (AC 10 mix) to environmentally break even. If 70% ABR is the benchmark for base layers, the SL with no RAP should be 66% longer to yield the same economic and environmental impact. Adding rejuvenators to 70% ABR requires a 13% extension in SL to environmentally break even with the benchmark. The second objective was to identify the main contributors to the economic and environmental impact to streamline further efforts to reduce the impact of asphalt pavements. The results showed that 45% to 76% of the NPV is allocated to bitumen, plant operation, aggregates, and raw material transport. Regarding environmental impact, three processes account for 44% to 72% of the impact: bitumen, raw material transport and energy consumption during asphalt production.

Development of an analytical method based on solid-phase extraction and LC-MS/MS for the monitoring of current-use pesticides and their metabolites in human urine

Abstract: Pyrethroids, organophosphorus pesticides and fipronil have been listed as priority chemicals in human biomonitoring studies because of their wide use and potential health effects in humans. The determination of 13 pesticides, including pyrethroids (deltamethrin, cypermethrin, permethrin, cyfluthrin, bifenthrin), organophosphorus (chlorpyrifos, chlorpyrifos-methyl, and malathion), fipronil, neonicotinoids (imidacloprid, acetamiprid and thiacloprid) and triazole (prothioconazole), together with 13 corresponding metabolites in human urine samples was achieved by solid-phase extraction and analysis by liquid chromatography coupled to tandem mass spectrometry. All targeted compounds, except malathion dicarboxylic acid, were measured with a mean within-accuracy (n = 5) of 71%–114% (RSD: 1%–14%) and between-run (n = 15) accuracy of 80%–118% (RSD: 2%–14%). Limits of quantitation of the targeted analytes ranged from 0.1 to 16 pg/mL. The detection result of urine samples from 25 volunteers indicated that the detection frequencies of 3,5,6-trichloro-2-pyridinol (median: 448 pg/mL), 6-chloropyridine-3-carboxylic acid (median: 193 pg/mL), 2-methyl-3-phenylbenzoic acid (median: 181 pg/mL), 3-phenoxybenzoic acid (median: 99 pg/mL), 2-isopropyl-6-methyl-4-pyrimidinol (median: 77 pg/mL), cyfluthrin (median: 59 pg/mL), cis-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (cis-DCCA, median: 53 pg/mL), trans-DCCA (median: 25 pg/mL), prothioconazole (median: 21 pg/mL), imidacloprid (median: 7 pg/mL), and prothioconazole-desthio (median: 1 pg/mL) were > 50%. The obtained results show that the validated method is suitable for the human biomonitoring of these current-use pesticides and their metabolites.

The Roles of Unrecognized Mpox Cases, Contact Isolation and Vaccination in Determining Epidemic Size in Belgium: A Modeling Study

Abstract: Abstract We used a network model to simulate a mpox epidemic among men who have sex with men. Our findings suggest that unrecognized infections have an important impact on the epidemic, and that vaccination of individuals at highest risk of infection reduces epidemic size more than post-exposure vaccination of sexual partners.

Sclerostin Protects Against Vascular Calcification Development in Mice

Abstract: Sclerostin is a negative regulator of the Wnt/β-catenin signaling and is, therefore, an important inhibitor of bone formation and turnover. Because ectopic vascular calcification develops in a similar way to bone formation, one might reasonably attribute a role to sclerostin in this pathological process. Ectopic calcification, especially vascular calcification, importantly contributes to mortality in elderly and patients with diabetes, osteoporosis, chronic kidney disease (CKD), and hypertension. The central players in this ectopic calcification process are the vascular smooth muscle cells that undergo dedifferentiation and thereby acquire characteristics of bonelike cells. Therefore, we hypothesize that depletion/deactivation of the Wnt/β-catenin signaling inhibitor sclerostin may promote the development of ectopic calcifications through stimulation of bone-anabolic effects at the level of the arteries. We investigated the role of sclerostin (encoded by the Sost gene) during vascular calcification by using either Sost-/- mice or anti-sclerostin antibody. Sost-/- and wild-type (WT) mice (C57BL/6J background) were administered an adenine-containing diet to promote the development of CKD-induced vascular calcification. Calcifications developed more extensively in the cardiac vessels of adenine-exposed Sost-/- mice, compared to adenine-exposed WT mice. This could be concluded from the cardiac calcium content as well as from cardiac tissue sections on which calcifications were visualized histochemically. In a second experiment, DBA/2J mice were administered a warfarin-containing diet to induce vascular calcifications in the absence of CKD. Here, warfarin exposure led to significantly increased aortic and renal tissue calcium content. Calcifications, which were present in the aortic medial layer and renal vessels, were significantly more pronounced when warfarin treatment was combined with anti-sclerostin antibody treatment. This study demonstrates a protective effect of sclerostin during vascular calcification. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Targeting hedgehog signaling in pancreatic ductal adenocarcinoma

Abstract: Pancreatic ductal adenocarcinoma (PDAC) remains a leading cause of cancer related death. The urgent need for effective therapies is highlighted by the lack of adequate targeting. In PDAC, hedgehog (Hh) signaling is known to be aberrantly activated, which prompted the pathway as a possible target for effective treatment for PDAC patients. Unfortunately, specific targeting of upstream molecules within the Hh signaling pathway failed to bring clinical benefit. This led to the ongoing debate on Hh targeting as a therapeutic treatment for PDAC patients. Additionally, concurrent non-canonical activation routes also result in translocation of Gli transcription factors into the nucleus. Therefore, different downstream targets of the Hh signaling pathway were identified and evaluated in preclinical and clinical research. In this review we summarize the variety of Hh signaling antagonists in different preclinical models of PDAC. Furthermore, we discuss published and ongoing clinical trials that evaluated Hh antagonists and point out the current hurdles and future perspectives in the light of redesigning Hh-targeting therapies for the treatment of PDAC patients.

Development of an analytical method based on solid-phase extraction and LC-MS/MS for the monitoring of current-use pesticides and their metabolites in human urine

Abstract: Pyrethroids, organophosphorus pesticides and fipronil have been listed as priority chemicals in human biomonitoring studies because of their wide use and potential health effects in humans. The determination of 13 pesticides, including pyrethroids (deltamethrin, cypermethrin, permethrin, cyfluthrin, bifenthrin), organophosphorus (chlorpyrifos, chlorpyrifos-methyl, and malathion), fipronil, neonicotinoids (imidacloprid, acetamiprid and thiacloprid) and triazole (prothioconazole), together with 13 corresponding metabolites in human urine samples was achieved by solid-phase extraction and analysis by liquid chromatography coupled to tandem mass spectrometry. All targeted compounds, except malathion dicarboxylic acid, were measured with a mean within-accuracy (n = 5) of 71%-114% (RSD: 1%-14%) and between-run (n = 15) accuracy of 80%-118% (RSD: 2%-14%). Limits of quantitation of the targeted analytes ranged from 0.1 to 16 pg/mL. The detection result of urine samples from 25 volunteers indicated that the detection frequencies of 3,5,6-trichloro-2-pyridinol (median: 448 pg/mL), 6-chloropyridine-3-carboxylic acid (median: 193 pg/mL), 2-methyl-3-phenylbenzoic acid (median: 181 pg/mL), 3-phenoxybenzoic acid (median: 99 pg/mL), 2-isopropyl-6-methyl-4-pyrimidinol (median: 77 pg/mL), cyfluthrin (median: 59 pg/mL), cis-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (cis-DCCA, median: 53 pg/mL), trans-DCCA (median: 25 pg/mL), prothioconazole (median: 21 pg/mL), imidacloprid (median: 7 pg/mL), and prothioconazole-desthio (median: 1 pg/mL) were > 50%. The obtained results show that the validated method is suitable for the human biomonitoring of these current-use pesticides and their metabolites.

Nanopore Sequencing for Mycobacterium tuberculosis: a Critical Review of the Literature, New Developments, and Future Opportunities

Abstract: The next-generation, short-read sequencing technologies that generate comprehensive, whole-genome data with single nucleotide resolution have already advanced tuberculosis diagnosis, treatment, surveillance, and source investigation. Their high costs, tedious and lengthy processes, and large equipment remain major hurdles for research use in high tuberculosis burden countries and implementation into routine care. The portable next-generation sequencing devices developed by Oxford Nanopore Technologies (ONT) are attractive alternatives due to their long-read sequence capability, compact low-cost hardware, and continued improvements in accuracy and throughput. A systematic review of the published literature demonstrated limited uptake of ONT sequencing in tuberculosis research and clinical care. Of the 12 eligible articles presenting ONT sequencing data on at least one Mycobacterium tuberculosis sample, four addressed software development for long-read ONT sequencing data with potential applications for M. tuberculosis. Only eight studies presented results of ONT sequencing of M. tuberculosis, of which five performed whole-genome and three did targeted sequencing. Based on these findings, we summarize the standard processes, reflect on the current limitations of ONT sequencing technology, and the research needed to overcome the main hurdles. The low capital cost, portable nature and continued improvement in the performance of ONT sequencing make it an attractive option for sequencing for research and clinical care, but limited data are available on its application in the tuberculosis field. Important research investment is needed to unleash the full potential of ONT sequencing for tuberculosis research and care.

Rock Fragmentation Prediction Using an Artificial Neural Network and Support Vector Regression Hybrid Approach

Abstract: While empirical rock fragmentation models are easy to parameterize for blast design, they are usually prone to errors, resulting in less accurate fragment size prediction. Among other shortfalls, these models may be unable to accurately account for the nonlinear relationship that exists between fragmentation input and output parameters. Machine learning (ML) algorithms are potentially able to better account for the nonlinear relationship. To this end, we assess the potential of the multilayered artificial neural network (ANN) and support vector regression (SVR) ML techniques in rock fragmentation prediction. Using geometric, explosives, and rock parameters, we build ANN and SVR models to predict mean rock fragment size. Both models yield satisfactory results and show higher performance when compared with the conventional Kuznetsov model. We further demonstrate an automated means of analyzing a varied number of hidden layers for an ANN using Bayesian optimization in the Keras Python library.

Harmonic-binomial Euler-like sums via expansions of $$(\arcsin x)^p$$ ( arcsin x ) p

Abstract: In this paper we evaluate Euler-like sums involving harmonic/odd harmonic numbers and central binomial coefficients by using the expansion for powers of the inverse sine function. We also evaluate a number of integrals which in turn give rise to new central binomial coefficient and harmonic number identities.