| 1. |
- Beal, Jacob, et al.
(författare)
-
Robust estimation of bacterial cell count from optical density
- 2020
-
Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
-
Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
|
|
| 2. |
- Ademuyiwa, Adesoji O., et al.
(författare)
-
Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
-
Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
|
|
| 3. |
- Dengler, Juergen, et al.
(författare)
-
GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
- 2018
-
Ingår i: Phytocoenologia. - : Schweizerbart. - 0340-269X. ; 48:3, s. 331-347
-
Tidskriftsartikel (refereegranskat)abstract
- GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
|
|
| 4. |
- Manry, Jérémy, et al.
(författare)
-
The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies.
- 2022
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 119:21
-
Tidskriftsartikel (refereegranskat)abstract
- Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection fatality rate (IFR) doubles with every 5 y of age from childhood onward. Circulating autoantibodies neutralizing IFN-α, IFN-ω, and/or IFN-β are found in ∼20% of deceased patients across age groups, and in ∼1% of individuals aged <70 y and in >4% of those >70 y old in the general population. With a sample of 1,261 unvaccinated deceased patients and 34,159 individuals of the general population sampled before the pandemic, we estimated both IFR and relative risk of death (RRD) across age groups for individuals carrying autoantibodies neutralizing type I IFNs, relative to noncarriers. The RRD associated with any combination of autoantibodies was higher in subjects under 70 y old. For autoantibodies neutralizing IFN-α2 or IFN-ω, the RRDs were 17.0 (95% CI: 11.7 to 24.7) and 5.8 (4.5 to 7.4) for individuals <70 y and ≥70 y old, respectively, whereas, for autoantibodies neutralizing both molecules, the RRDs were 188.3 (44.8 to 774.4) and 7.2 (5.0 to 10.3), respectively. In contrast, IFRs increased with age, ranging from 0.17% (0.12 to 0.31) for individuals <40 y old to 26.7% (20.3 to 35.2) for those ≥80 y old for autoantibodies neutralizing IFN-α2 or IFN-ω, and from 0.84% (0.31 to 8.28) to 40.5% (27.82 to 61.20) for autoantibodies neutralizing both. Autoantibodies against type I IFNs increase IFRs, and are associated with high RRDs, especially when neutralizing both IFN-α2 and IFN-ω. Remarkably, IFRs increase with age, whereas RRDs decrease with age. Autoimmunity to type I IFNs is a strong and common predictor of COVID-19 death.
|
|
| 5. |
- Minola, Lorenzo, et al.
(författare)
-
Climatology of near-surface wind speed from observational, reanalysis and high-resolution regional climate model data over the Tibetan Plateau
- 2023
-
Ingår i: Climate Dynamics. - 0930-7575 .- 1432-0894.
-
Tidskriftsartikel (refereegranskat)abstract
- As near-surface wind speed plays a role in regulating surface evaporation and thus the hydrological cycle, it is crucial to explore its spatio-temporal characteristics. However, in-situ measurements are scarce over the Tibetan Plateau, limiting the understanding of wind speed climate across this high-elevation region. This study explores the climatology of near-surface wind speed over the Tibetan Plateau by using for the first time homogenized observations together with reanalysis products and regional climate model simulations. Measuring stations across the center and the west of the plateau are at higher elevations and display higher mean and standard deviation, confirming that wind speed increases with increasing altitude. By exploring wind characteristics with a focus on seasonal cycle through cluster analysis, three regions of distinct wind regimes can be identified: (1) the central Tibetan Plateau, characterized by high elevation; (2) the eastern and the peripheral areas of the plateau; and (3) the Qaidam basin, a topographic depression strongly influenced by the blocking effect of the surrounding mountainous terrain. Notably, the ERA5 reanalysis, with its improvements in horizontal, vertical, and temporal spacing, model physics and data assimilation, demonstrates closer agreement to the measured wind conditions than its predecessor ERA-Interim. It successfully reproduces the three identified wind regimes. However, the newest ERA5-Land product does not show improvements compared to ERA5, most likely because they share most of the parametrizations. Furthermore, the two dynamical downscalings of ERA5 analyzed here fail to capture the observed wind statistics and exhibit notable biases and discrepancies also when investigating the diurnal variations. Consequently, these high-resolution downscaling products do not show add value in reproducing the observed climatology of wind speed compared to ERA5 over the Tibetan Plateau.
|
|
| 6. |
- Phillips, Helen R. P., et al.
(författare)
-
Global distribution of earthworm diversity
- 2019
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 366:6464, s. 480-
-
Tidskriftsartikel (refereegranskat)abstract
- Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide.
|
|
| 7. |
- Bousquet, Jean, et al.
(författare)
-
ARIA digital anamorphosis : Digital transformation of health and care in airway diseases from research to practice
- 2021
-
Ingår i: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 76:1, s. 168-190
-
Forskningsöversikt (refereegranskat)abstract
- Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.
|
|
| 8. |
- Ekström, Ulf, et al.
(författare)
-
Internalization of cystatin C in human cell lines.
- 2008
-
Ingår i: The FEBS Journal. - : Wiley. - 1742-464X. ; Aug 9, s. 4571-4582
-
Tidskriftsartikel (refereegranskat)abstract
- Altered protease activity is considered important for tumour invasion and metastasis, processes in which the cysteine proteases cathepsin B and L are involved. Their natural inhibitor cystatin C is a secreted protein, suggesting that it functions to control extracellular protease activity. Because cystatins added to cell cultures can inhibit polio, herpes simplex and coronavirus replication, which are intracellular processes, the internalization and intracellular regulation of cysteine proteases by cystatin C should be considered. The extension, mechanism and biological importance of this hypothetical process are unknown. We investigated whether internalization of cystatin C occurs in a set of human cell lines. Demonstrated by flow cytometry and confocal microscopy, A-431, MCF-7, MDA-MB-453, MDA-MB-468 and Capan-1 cells internalized fluorophore-conjugated cystatin C when exposed to physiological concentrations (1 mum). During cystatin C incubation, intracellular cystatin C increased after 5 min and accumulated for at least 6 h, reaching four to six times the baseline level. Western blotting showed that the internalized inhibitor was not degraded. It was functionally intact and extracts of cells exposed to cystatin C showed a higher capacity to inhibit papain and cathepsin B than control cells (decrease in enzyme activity of 34% and 37%, respectively). The uptake of labelled cystatin C was inhibited by unlabelled inhibitor, suggesting a specific pathway for the internalization. We conclude that the cysteine protease inhibitor cystatin C is internalized in significant quantities in various cancer cell lines. This is a potentially important physiological phenomenon not previously described for this group of inhibitors.
|
|
| 9. |
- Franci, Luca, et al.
(författare)
-
Modeling MMS Observations at the Earth's Magnetopause with Hybrid Simulations of Alfvenic Turbulence
- 2020
-
Ingår i: Astrophysical Journal. - : IOP PUBLISHING LTD. - 0004-637X .- 1538-4357. ; 898:2
-
Tidskriftsartikel (refereegranskat)abstract
- Magnetospheric Multiscale (MMS) observations of plasma turbulence generated by a Kelvin-Helmholtz (KH) event at the Earth's magnetopause are compared with a high-resolution two-dimensional (2D) hybrid direct numerical simulation of decaying plasma turbulence driven by large-scale balanced Alfvenic fluctuations. The simulation, set up with four observation-driven physical parameters (ion and electron betas, turbulence strength, and injection scale), exhibits a quantitative agreement on the spectral, intermittency, and cascade-rate properties with in situ observations, despite the different driving mechanisms. Such agreement demonstrates a certain universality of the turbulent cascade from magnetohydrodynamic to sub-ion scales, whose properties are mainly determined by the selected parameters, also indicating that the KH instability-driven turbulence has a quasi-2D nature. The fact that our results are compatible with the validity of the Taylor hypothesis, in the whole range of scales investigated numerically, suggests that the fluctuations at sub-ion scales might have predominantly low frequencies. This would be consistent with a kinetic Alfven wave-like nature and/or with the presence of quasi-static structures. Finally, the third-order structure function analysis indicates that the cascade rate of the turbulence generated by a KH event at the magnetopause is an order of magnitude larger than in the ambient magnetosheath.
|
|
| 10. |
- Gaulton, Kyle J, et al.
(författare)
-
Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.
- 2015
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:12, s. 1415-1415
-
Tidskriftsartikel (refereegranskat)abstract
- We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
|
|
| 11. |
- Helland, Ragnhild Holden, et al.
(författare)
-
Segmentation of glioblastomas in early post-operative multi-modal MRI with deep neural networks.
- 2023
-
Ingår i: Scientific reports. - 2045-2322. ; 13:1
-
Tidskriftsartikel (refereegranskat)abstract
- Extent of resection after surgery is one of the main prognostic factors for patients diagnosed with glioblastoma. To achieve this, accurate segmentation and classification of residual tumor from post-operative MR images is essential. The current standard method for estimating it is subject to high inter- and intra-rater variability, and an automated method for segmentation of residual tumor in early post-operative MRI could lead to a more accurate estimation of extent of resection. In this study, two state-of-the-art neural network architectures for pre-operative segmentation were trained for the task. The models were extensively validated on a multicenter dataset with nearly 1000 patients, from 12 hospitals in Europe and the United States. The best performance achieved was a 61% Dice score, and the best classification performance was about 80% balanced accuracy, with a demonstrated ability to generalize across hospitals. In addition, the segmentation performance of the best models was on par with human expert raters. The predicted segmentations can be used to accurately classify the patients into those with residual tumor, and those with gross total resection.
|
|
| 12. |
- Hernandez, Victor, et al.
(författare)
-
What is plan quality in radiotherapy? The importance of evaluating dose metrics, complexity, and robustness of treatment plans.
- 2020
-
Ingår i: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. - : Elsevier BV. - 1879-0887. ; 153, s. 26-33
-
Tidskriftsartikel (refereegranskat)abstract
- Plan evaluation is a key step in the radiotherapy treatment workflow. Central to this step is the assessment of treatment plan quality. Hence, it is important to agree on what we mean by plan quality and to be fully aware of which parameters it depends on. We understand plan quality in radiotherapy as the clinical suitability of the delivered dose distribution that can be realistically expected from a treatment plan. Plan quality is commonly assessed by evaluating the dose distribution calculated by the treatment planning system (TPS). Evaluating the 3D dose distribution is not easy, however; it is hard to fully evaluate its spatial characteristics and we still lack the knowledge for personalising the prediction of the clinical outcome based on individual patient characteristics. This advocates for standardisation and systematic collection of clinical data and outcomes after radiotherapy. Additionally, the calculated dose distribution is not exactly the dose delivered to the patient due to uncertainties in the dose calculation and the treatment delivery, including variations in the patient set-up and anatomy. Consequently, plan quality also depends on the robustness and complexity of the treatment plan. We believe that future work and consensus on the best metrics for quality indices are required. Better tools are needed in TPSs for the evaluation of dose distributions, for the robust evaluation and optimisation of treatment plans, and for controlling and reporting plan complexity. Implementation of such tools and a better understanding of these concepts will facilitate the handling of these characteristics in clinical practice and be helpful to increase the overall quality of treatment plans in radiotherapy.
|
|
| 13. |
- Herold, Nikolas, et al.
(författare)
-
Targeting SAMHD1 with the Vpx protein to improve cytarabine therapy for hematological malignancies
- 2017
-
Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1078-8956 .- 1546-170X. ; 23:2, s. 256-263
-
Tidskriftsartikel (refereegranskat)abstract
- The cytostatic deoxycytidine analog cytarabine (ara-C) is the most active agent available against acute myelogenous leukemia (AML). Together with anthracyclines, ara-C forms the backbone of AML treatment for children and adults'. In AML, both the cytotoxicity of ara-C in vitro and the clinical response to ara-C therapy are correlated with the ability of AML blasts to accumulate the active metabolite ara-C triphosphate (ara-CTP)(2-5), which causes DNA damage through perturbation of DNA synthesis(6). Differences in expression levels of known transporters or metabolic enzymes relevant to ara-C only partially account for patient-specific differential ara-CTP accumulation in AML blasts and response to ara-C treatment(7-9). Here we demonstrate that the deoxynucleoside triphosphate (dNTP) triphosphohydrolase SAM domain and HD domain 1 (SAMHD1) promotes the detoxification of intracellular ara-CTP pools. Recombinant SAMHD1 exhibited ara-CTPase activity in vitro, and cells in which SAMHD1 expression was transiently reduced by treatment with the simian immunodeficiency virus (SIV) protein Vpx were dramatically more sensitive to ara-C-induced cytotoxicity. CRISPR-Cas9-mediated disruption of the gene encoding SAMHD1 sensitized cells to ara-C, and this sensitivity could be abrogated by ectopic expression of wild-type (WT), but not dNTPase-deficient, SAMHD1. Mouse models of AML lacking SAMHD1 were hypersensitive to ara-C, and treatment ex vivo with Vpx sensitized primary patient derived AML blasts to ara-C. Finally, we identified SAMHD1 as a risk factor in cohorts of both pediatric and adult patients with de novo AML who received ara-C treatment. Thus, SAMHD1 expression levels dictate patient sensitivity to ara-C, providing proof-of-concept that the targeting of SAMHD1 by Vpx could be an attractive therapeutic strategy for potentiating ara-C efficacy in hematological malignancies.
|
|
| 14. |
- Kemppinen, Julia, et al.
(författare)
-
Microclimate, an important part of ecology and biogeography
- 2024
-
Ingår i: GLOBAL ECOLOGY AND BIOGEOGRAPHY. - 1466-822X .- 1466-8238. ; 33:6
-
Tidskriftsartikel (refereegranskat)abstract
- Brief introduction: What are microclimates and why are they important?Microclimate science has developed into a global discipline. Microclimate science is increasingly used to understand and mitigate climate and biodiversity shifts. Here, we provide an overview of the current status of microclimate ecology and biogeography in terrestrial ecosystems, and where this field is heading next.Microclimate investigations in ecology and biogeographyWe highlight the latest research on interactions between microclimates and organisms, including how microclimates influence individuals, and through them populations, communities and entire ecosystems and their processes. We also briefly discuss recent research on how organisms shape microclimates from the tropics to the poles.Microclimate applications in ecosystem managementMicroclimates are also important in ecosystem management under climate change. We showcase new research in microclimate management with examples from biodiversity conservation, forestry and urban ecology. We discuss the importance of microrefugia in conservation and how to promote microclimate heterogeneity.Methods for microclimate scienceWe showcase the recent advances in data acquisition, such as novel field sensors and remote sensing methods. We discuss microclimate modelling, mapping and data processing, including accessibility of modelling tools, advantages of mechanistic and statistical modelling and solutions for computational challenges that have pushed the state-of-the-art of the field.What's next?We identify major knowledge gaps that need to be filled for further advancing microclimate investigations, applications and methods. These gaps include spatiotemporal scaling of microclimate data, mismatches between macroclimate and microclimate in predicting responses of organisms to climate change, and the need for more evidence on the outcomes of microclimate management.
|
|
| 15. |
|
|
| 16. |
- Kowal-Bielecka, Otylia, et al.
(författare)
-
Update of EULAR recommendations for the treatment of systemic sclerosis
- 2017
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 76, s. 1327-1339
-
Tidskriftsartikel (refereegranskat)abstract
- The aim was to update the 2009 European League against Rheumatism (EULAR) recommendations for the treatment of systemic sclerosis (SSc), with attention to new therapeutic questions. Update of the previous treatment recommendations was performed according to EULAR standard operating procedures. The task force consisted of 32 SSc clinical experts from Europe and the USA, 2 patients nominated by the pan-European patient association for SSc (Federation of European Scleroderma Associations (FESCA)), a clinical epidemiologist and 2 research fellows. All centres from the EULAR Scleroderma Trials and Research group were invited to submit and select clinical questions concerning SSc treatment using a Delphi approach. Accordingly, 46 clinical questions addressing 26 different interventions were selected for systematic literature review. The new recommendations were based on the available evidence and developed in a consensus meeting with clinical experts and patients. The procedure resulted in 16 recommendations being developed (instead of 14 in 2009) that address treatment of several SSc-related organ complications: Raynaud's phenomenon (RP), digital ulcers (DUs), pulmonary arterial hypertension (PAH), skin and lung disease, scleroderma renal crisis and gastrointestinal involvement. Compared with the 2009 recommendations, the 2016 recommendations include phosphodiesterase type 5 (PDE-5) inhibitors for the treatment of SSc-related RP and DUs, riociguat, new aspects for endothelin receptor antagonists, prostacyclin analogues and PDE-5 inhibitors for SSc-related PAH. New recommendations regarding the use of fluoxetine for SSc-related RP and haematopoietic stem cell transplantation for selected patients with rapidly progressive SSc were also added. In addition, several comments regarding other treatments addressed in clinical questions and suggestions for the SSc research agenda were formulated. These updated data-derived and consensus-derived recommendations will help rheumatologists to manage patients with SSc in an evidence-based way. These recommendations also give directions for future clinical research in SSc.
|
|
| 17. |
- Lewis, Harry C., et al.
(författare)
-
Magnetospheric Multiscale measurements of turbulent electric fields in earth's magnetosheath : How do plasma conditions influence the balance of terms in generalized Ohm's law?
- 2023
-
Ingår i: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 30:8
-
Tidskriftsartikel (refereegranskat)abstract
- Turbulence is ubiquitous within space plasmas, where it is associated with numerous nonlinear interactions. Magnetospheric Multiscale (MMS) provides the unique opportunity to decompose the electric field (E) dynamics into contributions from different linear and nonlinear processes via direct measurements of the terms in generalized Ohm's law. Using high-resolution multipoint measurements, we compute the magnetohydrodynamic ( E MHD ), Hall ( E Hall ), electron pressure ( E P e ), and electron inertia ( E inertia ) terms for 60 turbulent magnetosheath intervals, to uncover the varying contributions to the dynamics as a function of scale for different plasma conditions. We identify key spectral characteristics of the Ohm's law terms: the Hall scale, k Hall , where E Hall becomes dominant over E MHD ; the relative amplitude of E P e to E Hall , which is constant in the sub-ion range; and the relative scaling of the nonlinear and linear components of E MHD and of E Hall , which are independent of scale. We find expressions for the characteristics as a function of plasma conditions. The underlying relationship between turbulent fluctuation amplitudes and ambient plasma conditions is discussed. Depending on the interval, we observe that E MHD and E Hall can be dominated by either nonlinear or linear dynamics. We find that E P e is dominated by its linear contributions, with a tendency for electron temperature fluctuations to dominate at small scales. The findings are not consistent with existing linear kinetic Alfvén wave theory for isothermal fluctuations. Our work shows how contributions to turbulent dynamics change in different plasma conditions, which may provide insight into other turbulent plasma environments.
|
|
| 18. |
- Morana, Marta, et al.
(författare)
-
Cubic or Not Cubic? Combined Experimental and Computational Investigation of the Short-Range Order of Tin Halide Perovskites
- 2023
-
Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 14, s. 2178-2186
-
Tidskriftsartikel (refereegranskat)abstract
- Tin-based metal halide perovskites with a composition of ASnX3 (where A= MA or FA and X = I or Br) have been investigated by means of X-ray total scattering techniques coupled to pair distribution function (PDF) analysis. These studies revealed that that none of the four perovskites has a cubic symmetry at the local scale and that a degree of increasing distortion is always present, in particular when the cation size is increased, i.e., from MA to FA, and the hardness of the anion is increased, i.e., from Br- to I-. Electronic structure calculations provided good agreement with experimental band gaps for the four perovskites when local dynamical distortions were included in the calculations. The averaged structure obtained from molecular dynamics simulations was consistent with experimental local structures determined via X-ray PDF, thus highlighting the robustness of computational modeling and strengthening the correlation between experimental and computational results.
|
|
| 19. |
- Pradhan, Prajal, et al.
(författare)
-
Methods for Analysing Steering Effects of Global Goals
- 2022
-
Ingår i: The Political Impact of the Sustainable Development Goals : Transforming Governance Through Global Goals? - Transforming Governance Through Global Goals?. - : Cambridge University Press. - 9781316514290 - 9781009082945 ; , s. 172-203
-
Bokkapitel (refereegranskat)abstract
- This chapter provides an overview of the multi-faceted landscape of methods used to study the steering effects of the Sustainable Development Goals. After a discussion of the political use of science and the complex relations between science and politics, the chapter showcases a selection of different methods that are employed to trace the steering effects of the Sustainable Development Goals. Selecting the most suitable method for a particular research question requires understanding their main characteristics, strengths and weaknesses. The chapter highlights that all methods and tools need to be combined to comprehensively assess the political impact of the goals, the progress towards their achievement, and their overall transformative potential. As data gaps and unequal geographical coverage still hamper a broader understanding of the political impact of the global goals, we need to build bridges across language communities, disciplines and methodological camps, which still work very much in isolation.
|
|
| 20. |
- Prinoth, Bibiana, et al.
(författare)
-
Titanium oxide and chemical inhomogeneity in the atmosphere of the exoplanet WASP-189 b
- 2022
-
Ingår i: Nature Astronomy. - : Springer Science and Business Media LLC. - 2397-3366. ; 6:4, s. 449-457
-
Tidskriftsartikel (refereegranskat)abstract
- The temperature of an atmosphere decreases with increasing altitude, unless a shortwave absorber that causes a temperature inversion exists. Ozone plays this role in the Earth’s atmosphere. In the atmospheres of highly irradiated exoplanets, the shortwave absorbers are predicted to be titanium oxide (TiO) and vanadium oxide (VO). Detections of TiO and VO have been claimed using both low-, and high- spectral-resolution observations, but subsequent observations have failed to confirm these claims or overturned them. Here we report the unambiguous detection of TiO in the ultra-hot Jupiter WASP-189 b using high-resolution transmission spectroscopy. This detection is based on applying the cross-correlation technique to many spectral lines of TiO from 460 to 690 nm. Moreover, we report detections of metals, including neutral and singly ionized iron and titanium, as well as chromium, magnesium, vanadium and manganese (Fe, Fe+, Ti, Ti+, Cr, Mg, V, Mn). The line positions of the detected species differ, which we interpret as a consequence of spatial gradients in their chemical abundances, such that they exist in different regions or dynamical regimes. This is direct observational evidence for the three-dimensional thermochemical stratification of an exoplanet atmosphere derived from high-resolution ground-based spectroscopy.
|
|
| 21. |
- Ricciarelli, Damiano, et al.
(författare)
-
Electron bipolarons at the DMASnBr 3 –water interface: Effect on the photocatalytic hydrogen production
- 2024
-
Ingår i: International Journal of Hydrogen Energy. - 0360-3199. ; 58, s. 863-871
-
Tidskriftsartikel (refereegranskat)abstract
- In this article, we report on advanced molecular dynamics simulations of the atomistic DMASnBr3–water interface, which, coupled with a grand-canonical formulation of adsorbates and defects, elucidate the surface chemistry and reactivity of this novel water-stable perovskite and highlight the role of small electron bipolarons in photocatalytic hydrogen production. We find that the extremely acidic nature of the surface Br atoms does not allow for significant adsorption of protons at the interface under charge-neutral conditions. However, when electrons are accumulated on the surface, the formation of a small electron bipolaron in the form of a Sn-Sn dimer provides the required electron localization to drive adsorption of H, which is assimilated on surface Sn atoms as hydride. Finally, we estimate a favourable alignment between the bipolaron energy level and the H+/H2 redox level, which suggests the occurrence of a feasible route for hydrogen evolution, bypassing the common reaction mechanism.
|
|
| 22. |
- Ricciarelli, Damiano, et al.
(författare)
-
Reaction Mechanism of Photocatalytic Hydrogen Production at Water/Tin Halide Perovskite Interfaces
- 2022
-
Ingår i: ACS Energy Letters. - : American Chemical Society (ACS). - 2380-8195. ; 7, s. 1308-1315
-
Tidskriftsartikel (refereegranskat)abstract
- While instability in aqueous environment has long impeded employment of metal halide perovskites for heterogeneous photocatalysis, recent reports have shown that some particular tin halide perovskites (THPs) can be water-stable and active in photocatalytic hydrogen production. To unravel the mechanistic details underlying the photocatalytic activity of THPs, we compare the reactivity of the water-stable and active DMASnBr3 (DMA = dimethylammonium) perovskite against prototypical MASnI3 and MASnBr3 compounds (MA = methylammonium), employing advanced electronic-structure calculations. We find that the binding energy of electron polarons at the surface of THPs, driven by the conduction band energetics, is cardinal for photocatalytic hydrogen reduction. In this framework, the interplay between the A-site cation and halogen is found to play a key role in defining the photoreactivity of the material by tuning the perovskite electronic energy levels. Our study, by elucidating the key steps of the reaction, may assist in development of more stable and efficient materials for photocatalytic hydrogen reduction.
|
|
| 23. |
- Staessen, Jan A., et al.
(författare)
-
Predictive performance and clinical application of COV50, a urinary proteomic biomarker in early COVID-19 infection : a prospective multicentre cohort study
- 2022
-
Ingår i: The Lancet Digital Health. - : Elsevier. - 2589-7500. ; 4:10, s. e727-e737
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The SARS-CoV-2 pandemic is a worldwide challenge. The CRIT-CoV-U pilot study generated a urinary proteomic biomarker consisting of 50 peptides (COV50), which predicted death and disease progression from SARS-CoV-2. After the interim analysis presented for the German Government, here, we aimed to analyse the full dataset to consolidate the findings and propose potential clinical applications of this biomarker.Methods: CRIT-CoV-U was a prospective multicentre cohort study. In eight European countries (Austria, France, Germany, Greece, North Macedonia, Poland, Spain, and Sweden), 1012 adults with PCR-confirmed COVID-19 were followed up for death and progression along the 8-point WHO scale. Capillary electrophoresis coupled with mass spectrometry was used for urinary proteomic profiling. Statistical methods included logistic regression and receiver operating characteristic curve analysis with a comparison of the area under curve (AUC) between nested models. Hospitalisation costs were derived from the care facility corresponding with the Markov chain probability of reaching WHO scores ranging from 3 to 8 and flat-rate hospitalisation costs adjusted for the gross per capita domestic product of each country.Findings: From June 30 to Nov 19, 2020, 228 participants were recruited, and from April 30, 2020, to April 14, 2021, 784 participants were recruited, resulting in a total of 1012 participants. The entry WHO scores were 1–3 in 445 (44%) participants, 4–5 in 529 (52%) participants, and 6 in 38 (4%) participants; and of all participants, 119 died and 271 had disease progression. The odds ratio (OR) associated with COV50 in all 1012 participants for death was 2·44 (95% CI 2·05–2·92) unadjusted and 1·67 (1·34–2·07) when adjusted for sex, age, BMI, comorbidities, and baseline WHO score; and for disease progression, the OR was 1·79 (1·60–2·01) when unadjusted and 1·63 (1·41–1·91) when adjusted (p<0·0001 for all). The predictive accuracy of the optimised COV50 thresholds was 74·4% (71·6–77·1%) for mortality (threshold 0·47) and 67·4% (64·4–70·3%) for disease progression (threshold 0·04). When adjusted for covariables and the baseline WHO score, these thresholds improved AUCs from 0·835 to 0·853 (p=0·033) for death and from 0·697 to 0·730 (p=0·0008) for progression. Of 196 participants who received ambulatory care, 194 (99%) did not reach the 0·04 threshold. The cost reductions associated with 1 day less hospitalisation per 1000 participants were million Euro (M€) 0·887 (5–95% percentile interval 0·730–1·039) in participants at a low risk (COV50 <0·04) and M€2·098 (1·839-2·365) in participants at a high risk (COV50 ≥0·04).Interpretation: The urinary proteomic COV50 marker might be predictive of adverse COVID-19 outcomes. Even in people with mild-to-moderate PCR-confirmed infections (WHO scores 1–4), the 0·04 COV50 threshold justifies earlier drug treatment, thereby potentially reducing the number of days in hospital and associated costs. Funding: German Federal Ministry of Health.
|
|
| 24. |
- Thompson, Robin N., et al.
(författare)
-
Key questions for modelling COVID-19 exit strategies
- 2020
-
Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 287:1932
-
Tidskriftsartikel (refereegranskat)abstract
- Combinations of intense non-pharmaceutical interventions (lockdowns) were introduced worldwide to reduce SARS-CoV-2 transmission. Many governments have begun to implement exit strategies that relax restrictions while attempting to control the risk of a surge in cases. Mathematical modelling has played a central role in guiding interventions, but the challenge of designing optimal exit strategies in the face of ongoing transmission is unprecedented. Here, we report discussions from the Isaac Newton Institute 'Models for an exit strategy' workshop (11-15 May 2020). A diverse community of modellers who are providing evidence to governments worldwide were asked to identify the main questions that, if answered, would allow for more accurate predictions of the effects of different exit strategies. Based on these questions, we propose a roadmap to facilitate the development of reliable models to guide exit strategies. This roadmap requires a global collaborative effort from the scientific community and policymakers, and has three parts: (i) improve estimation of key epidemiological parameters; (ii) understand sources of heterogeneity in populations; and (iii) focus on requirements for data collection, particularly in low-to-middle-income countries. This will provide important information for planning exit strategies that balance socio-economic benefits with public health.
|
|
| 25. |
- Vegvari, Carolin, et al.
(författare)
-
Commentary on the use of the reproduction number R during the COVID-19 pandemic
- 2022
-
Ingår i: Statistical Methods in Medical Research. - : SAGE Publications. - 0962-2802 .- 1477-0334. ; 31:9, s. 1675-1685
-
Tidskriftsartikel (refereegranskat)abstract
- Since the beginning of the COVID-19 pandemic, the reproduction number R has become a popular epidemiological metric used to communicate the state of the epidemic. At its most basic, R is defined as the average number of secondary infections caused by one primary infected individual. R seems convenient, because the epidemic is expanding if R>1 and contracting if R<1. The magnitude of R indicates by how much transmission needs to be reduced to control the epidemic. Using R in a naïve way can cause new problems. The reasons for this are threefold: (1) There is not just one definition of R but many, and the precise definition of R affects both its estimated value and how it should be interpreted. (2) Even with a particular clearly defined R, there may be different statistical methods used to estimate its value, and the choice of method will affect the estimate. (3) The availability and type of data used to estimate R vary, and it is not always clear what data should be included in the estimation. In this review, we discuss when R is useful, when it may be of use but needs to be interpreted with care, and when it may be an inappropriate indicator of the progress of the epidemic. We also argue that careful definition of R, and the data and methods used to estimate it, can make R a more useful metric for future management of the epidemic.
|
|
| 26. |
-
- 2019
-
Tidskriftsartikel (refereegranskat)
|
|
