| 1. |
- Pawłowski, P., et al.
(författare)
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Neutrons from projectile fragmentation at 600 MeV/nucleon
- 2023
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Ingår i: Physical Review C. - 2469-9993 .- 2469-9985. ; 108:4
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Tidskriftsartikel (refereegranskat)abstract
- The neutron emission in projectile fragmentation at relativistic energies was studied with the Large-Area-Neutron-Detector LAND coupled to the ALADIN forward spectrometer at the GSI Schwerionen-Synchrotron (SIS). Stable Sn124 and radioactive Sn107 and La124 beams with an incident energy of 600 MeV/nucleon were used to explore the N/Z dependence of the identified neutron source. A cluster-recognition algorithm is applied for identifying individual particles within the hit distributions registered with LAND. The obtained momentum distributions are extrapolated over the full phase space occupied by the neutrons from the projectile-spectator source. The mean multiplicities of spectator neutrons reach values of up to about 11 and depend strongly on the isotopic composition of the projectile. An effective source temperature of T≈2-5 MeV, monotonically increasing with decreasing impact parameter, is deduced from the transverse momentum distributions. For the interpretation of the data, calculations with the statistical multifragmentation model were performed. The variety of excited projectile spectators assumed to decay statistically is represented by an ensemble of excited sources with parameters determined previously from the fragment production observed in the same experiments. The obtained agreement is very satisfactory for more peripheral collisions where, according to the model, neutrons are mainly emitted during the secondary decays of excited fragments. The neutron multiplicity in more central collisions is underestimated, indicating that other sources besides the modeled statistical breakup contribute to the observed neutron yield. The choice made for the symmetry-term coefficient of the liquid-drop description of produced fragments has a weak effect on the predicted neutron multiplicities.
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| 2. |
- Sagova-Mareckova, M., et al.
(författare)
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Expanding ecological assessment by integrating microorganisms into routine freshwater biomonitoring
- 2021
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Ingår i: Water Research. - : Elsevier. - 0043-1354 .- 1879-2448. ; 191
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Forskningsöversikt (refereegranskat)abstract
- Bioindication has become an indispensable part of water quality monitoring in most countries of the world, with the presence and abundance of bioindicator taxa, mostly multicellular eukaryotes, used for biotic indices. In contrast, microbes (bacteria, archaea and protists) are seldom used as bioindicators in routine assessments, although they have been recognized for their importance in environmental processes. Recently, the use of molecular methods has revealed unexpected diversity within known functional groups and novel metabolic pathways that are particularly important in energy and nutrient cycling. In various habitats, microbial communities respond to eutrophication, metals, and natural or anthropogenic organic pollutants through changes in diversity and function. In this review, we evaluated the common trends in these changes, documenting that they have value as bioindicators and can be used not only for monitoring but also for improving our understanding of the major processes in lotic and lentic environments. Current knowledge provides a solid foundation for exploiting microbial taxa, community structures and diversity, as well as functional genes, in novel monitoring programs. These microbial community measures can also be combined into biotic indices, improving the resolution of individual bioindicators. Here, we assess particular molecular approaches complemented by advanced bioinformatic analysis, as these are the most promising with respect to detailed bioindication value. We conclude that microbial community dynamics are a missing link important for our understanding of rapid changes in the structure and function of aquatic ecosystems, and should be addressed in the future environmental monitoring of freshwater ecosystems. (c) 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/ )
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| 3. |
- Gaytán, Álvaro, 1988-, et al.
(författare)
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Changes in the foliar fungal community between oak leaf flushes along a latitudinal gradient in Europe
- 2022
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 49:12, s. 2269-2280
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Leaves support a large diversity of fungi, which are known to cause plant diseases, induce plant defences or influence leaf senescence and decomposition. To advance our understanding of how foliar fungal communities are structured and assembled, we assessed to what extent leaf flush and latitude can explain the within- and among-tree variation in foliar fungal communities.Location: A latitudinal gradient spanning c. 20 degrees in latitude in Europe.Taxa: The foliar fungal community associated with a foundation tree species, the pedunculate oak Quercus robur.Methods: We examined the main and interactive effects of leaf flush and latitude on the foliar fungal community by sampling 20 populations of the pedunculate oak Quercus robur across the tree's range. We used the ITS region as a target for characterization of fungal communities using DNA metabarcoding.Results: Species composition, but not species richness, differed between leaf flushes. Across the latitudinal gradient, species richness was highest in the central part of the oak's distributional range, and foliar fungal community composition shifted along the latitudinal gradient. Among fungal guilds, the relative abundance of plant pathogens and mycoparasites was lower on the first leaf flush, and the relative abundance of plant pathogens and saprotrophs decreased with latitude.Conclusions: Changes in community composition between leaf flushes and along the latitudinal gradient were mostly a result of species turnover. Overall, our findings demonstrate that leaf flush and latitude explain 5%–22% of the small- and large-scale spatial variation in the foliar fungal community on a foundation tree within the temperate region. Using space-for-time substitution, we expect that foliar fungal community structure will change with climate warming, with an increase in the abundance of plant pathogens and mycoparasites at higher latitudes, with major consequences for plant health, species interactions and ecosystem dynamics.
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| 4. |
- Lenart-Bugla, Marta, et al.
(författare)
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What Do We Know about Social and Non-Social Factors Influencing the Pathway from Cognitive Health to Dementia? A Systematic Review of Reviews
- 2022
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Ingår i: Brain Sciences. - : MDPI AG. - 2076-3425. ; 12:9
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Forskningsöversikt (refereegranskat)abstract
- The heterogeneous and multi-factorial nature of dementia requires the consideration of all health aspects when predicting the risk of its development and planning strategies for its prevention. This systematic review of reviews provides a comprehensive synthesis of those factors associated with cognition in the context of dementia, identifying the role of social aspects and evidencing knowledge gaps in this area of research. Systematic reviews and meta-analyses from 2009–2021 were searched for within Medline, PsycINFO, CINAHL Complete, Cochrane, and Epistemonikos. Reviewers independently screened, reviewed, and assessed the records, following the PRISMA-2020 guidelines. From 314 included studies, 624 cognitive-related factors were identified, most of them risk factors (61.2%), mainly belonging to the group of ‘somatic comorbidities’ (cardiovascular disease and diabetes) and ‘genetic predispositions’. The protective factors (20%) were mainly related to lifestyle, pointing to the Mediterranean diet, regular physical activity, and cognitively stimulating activities. Social factors constituted 9.6% of all identified factors. Research on biological and medical factors dominates the reviewed literature. Greater social support and frequent contact may confer some protection against cognitive decline and dementia by delaying its onset or reducing the overall risk; however, overall, our findings are inconsistent. Further research is needed in the fields of lifestyle, psychology, social health, and the protective factors against cognitive decline and dementia.
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| 5. |
- van Dijk, Laura J. A., 1990-, et al.
(författare)
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Single, but not dual, attack by a biotrophic pathogen and a sap-sucking insect affects the oak leaf metabolome
- 2022
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Ingår i: Frontiers in Plant Science. - : Frontiers Media S.A.. - 1664-462X. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Plants interact with a multitude of microorganisms and insects, both below- and above ground, which might influence plant metabolism. Despite this, we lack knowledge of the impact of natural soil communities and multiple aboveground attackers on the metabolic responses of plants, and whether plant metabolic responses to single attack can predict responses to dual attack. We used untargeted metabolic fingerprinting (gas chromatography-mass spectrometry, GC-MS) on leaves of the pedunculate oak, Quercus robur, to assess the metabolic response to different soil microbiomes and aboveground single and dual attack by oak powdery mildew (Erysiphe alphitoides) and the common oak aphid (Tuberculatus annulatus). Distinct soil microbiomes were not associated with differences in the metabolic profile of oak seedling leaves. Single attacks by aphids or mildew had pronounced but different effects on the oak leaf metabolome, but we detected no difference between the metabolomes of healthy seedlings and seedlings attacked by both aphids and powdery mildew. Our findings show that aboveground attackers can have species-specific and non-additive effects on the leaf metabolome of oak. The lack of a metabolic signature detected by GC-MS upon dual attack might suggest the existence of a potential negative feedback, and highlights the importance of considering the impacts of multiple attackers to gain mechanistic insights into the ecology and evolution of species interactions and the structure of plant-associated communities, as well as for the development of sustainable strategies to control agricultural pests and diseases and plant breeding.
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| 6. |
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| 7. |
- Lasota, Dorota, et al.
(författare)
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Alcohol and the Risk of Railway Suicide
- 2020
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Ingår i: International journal of environmental research and public health. - : MDPI AG. - 1660-4601. ; 17:19
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Tidskriftsartikel (refereegranskat)abstract
- Suicide is one of the ten most common causes of death in the world. Of all deaths from suicide, 22% can be attributed to the use of alcohol, which means that every fifth suicide would not occur if alcohol were not consumed by the population. People under the influence of alcohol choose more radical and effective methods of dying by suicide, e.g., throwing themselves under a moving vehicle, such as a train. The presented analysis aimed to determine important risk factors affecting railway suicide in Poland and their relation to the state of alcohol intoxication of the victims, and the relationship between ethyl alcohol consumption and the phenomenon of suicide. Documentation obtained from the Department of Forensic Medicine at the Medical University of Warsaw, in the form of death registers and forensic medical records concerning examination and autopsy, was analyzed. This made it possible to identify suicide victims from among pedestrian victims of railway accidents recorded during the period under study. The research was carried out using unidimensional and multidimensional statistical analyses with IBM SPSS Statistics, version 25. Sober suicide victims were statistically significantly older than victims under the influence of alcohol; alcohol concentration was correlated with the age of the victims-the older the victims were, the higher the alcohol concentration. A significantly higher number of deaths attributed to suicide by sober victims was observed in autumn compared to other seasons. Multidimensional analysis showed a statistically significant effect of age and season on the probability of dying by suicide under the influence of alcohol-this probability decreases with the age of the victims and is also significantly lower in autumn. The observed relationship between age and the presence of alcohol in suicide victims can be the cause of railway suicides. Knowledge of the mechanisms of seasonal variability of suicidal behavior can help to develop effective strategies to prevent railway suicides. It is necessary to improve the system of reporting railway suicides, as only reliable statistics provide the possibility of assessing both the scale of the problem and the effectiveness of actions taken.
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| 8. |
- Lüscher, Bernhard, et al.
(författare)
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ADP-ribosyltransferases, an update on function and nomenclature
- 2022
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Ingår i: The FEBS Journal. - : John Wiley & Sons. - 1742-464X .- 1742-4658. ; 289:23, s. 7399-7410
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Tidskriftsartikel (refereegranskat)abstract
- ADP-ribosylation, a modification of proteins, nucleic acids, and metabolites, confers broad functions, including roles in stress responses elicited, for example, by DNA damage and viral infection and is involved in intra- and extracellular signaling, chromatin and transcriptional regulation, protein biosynthesis, and cell death. ADP-ribosylation is catalyzed by ADP-ribosyltransferases (ARTs), which transfer ADP-ribose from NAD+ onto substrates. The modification, which occurs as mono- or poly-ADP-ribosylation, is reversible due to the action of different ADP-ribosylhydrolases. Importantly, inhibitors of ARTs are approved or are being developed for clinical use. Moreover, ADP-ribosylhydrolases are being assessed as therapeutic targets, foremost as antiviral drugs and for oncological indications. Due to the development of novel reagents and major technological advances that allow the study of ADP-ribosylation in unprecedented detail, an increasing number of cellular processes and pathways are being identified that are regulated by ADP-ribosylation. In addition, characterization of biochemical and structural aspects of the ARTs and their catalytic activities have expanded our understanding of this protein family. This increased knowledge requires that a common nomenclature be used to describe the relevant enzymes. Therefore, in this viewpoint, we propose an updated and broadly supported nomenclature for mammalian ARTs that will facilitate future discussions when addressing the biochemistry and biology of ADP-ribosylation. This is combined with a brief description of the main functions of mammalian ARTs to illustrate the increasing diversity of mono- and poly-ADP-ribose mediated cellular processes.
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| 9. |
- O'Brien, Phoebe A. J., 1995, et al.
(författare)
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Assessing the environmental quality of a historically-polluted fjord: a comparison of benthic foraminiferal eDNA and morphospecies proxy approaches
- 2023
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Ingår i: International Congress FORAMS2023, Perugia, Italy, 25-30th June, 2023. - : Micropress Europe & The Grzybowski Foundation.
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Konferensbidrag (refereegranskat)abstract
- Transitional environments present a unique challenge to Ecosystem Quality Status (EcoQS) assessment due to highly heterogenous conditions within the system, resulting in the “estuarine quality paradox”. Benthic foraminiferal assemblages provide high resolution environmental proxy records of the interaction between abiotic and biotic parameters in aqueous ecosystems. Fjords particularly have complex seabed topography which limits bottom water exchange and can result in hypoxia, and Idefjord on the Swedish Norwegian boarder is no exception. Although this oxygen decline is a natural occurrence which impairs fjord’s EcoQS, these ‘naturally stressed conditions’ complicate the definition of in-situ reference conditions if the system becomes subject to anthropogenic impact. At Idefjord the prolonged dumping of waste products from the paper and pulp manufacturing and bleaching industry, situated at the city of Halden, into the river Tista which feeds the fjord system, has led to a build-up of organic matter, sewage effluent and pollutant accumulation in the sediments. This study is the first assessment of foraminiferal diversity using sedimentary eDNA from one of the most polluted and anoxic fjords in Scandinavia, comparing the assemblage response reported by morphology-based and molecular ecosystem assessment techniques. Although index thresholds and genetic data processing decisions influence the EcoQS assessment category determined by each technique, both datasets report congruous responses in the benthic foraminiferal assemblages to pollution and environmental stress factors. Genetic methods tend to overestimate EcoQS at highly anoxic sites probably due to a presence of dormant propagules or extraorganismal DNA and suggesting that morphological methods are more suited to assessment in such conditions.
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| 10. |
- Park, Gina J., et al.
(författare)
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The mechanism of RNA capping by SARS-CoV-2
- 2022
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 609:7928, s. 793-800
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Tidskriftsartikel (refereegranskat)abstract
- The RNA genome of SARS-CoV-2 contains a 5′ cap that facilitates the translation of viral proteins, protection from exonucleases and evasion of the host immune response1–4. How this cap is made in SARS-CoV-2 is not completely understood. Here we reconstitute the N7- and 2′-O-methylated SARS-CoV-2 RNA cap (7MeGpppA2′-O-Me) using virally encoded non-structural proteins (nsps). We show that the kinase-like nidovirus RdRp-associated nucleotidyltransferase (NiRAN) domain5 of nsp12 transfers the RNA to the amino terminus of nsp9, forming a covalent RNA–protein intermediate (a process termed RNAylation). Subsequently, the NiRAN domain transfers the RNA to GDP, forming the core cap structure GpppA-RNA. The nsp146 and nsp167 methyltransferases then add methyl groups to form functional cap structures. Structural analyses of the replication–transcription complex bound to nsp9 identified key interactions that mediate the capping reaction. Furthermore, we demonstrate in a reverse genetics system8 that the N terminus of nsp9 and the kinase-like active-site residues in the NiRAN domain are required for successful SARS-CoV-2 replication. Collectively, our results reveal an unconventional mechanism by which SARS-CoV-2 caps its RNA genome, thus exposing a new target in the development of antivirals to treat COVID-19.
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