34 research outputs found

    European Mixed Forests: definition and research perspectives

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    peer-reviewedAim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) briefly review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material and methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any developmental stage, sharing common resources (light, water, and/or soil nutrients). The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used for specific objectives. A variety of structures and patterns of mixtures can occur, and the interactions between the component species and their relative proportions may change over time. The research perspectives identified are (i) species interactions and responses to hazards, (ii) the concept of maximum density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields of research indicate that gradient studies, experimental design approaches, and model simulations are key topics providing new research opportunities.The networking in this study has been supported by COST Action FP1206 EuMIXFOR

    Three Dimensional Structure of the MqsR:MqsA Complex: A Novel TA Pair Comprised of a Toxin Homologous to RelE and an Antitoxin with Unique Properties

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    One mechanism by which bacteria survive environmental stress is through the formation of bacterial persisters, a sub-population of genetically identical quiescent cells that exhibit multidrug tolerance and are highly enriched in bacterial toxins. Recently, the Escherichia coli gene mqsR (b3022) was identified as the gene most highly upregulated in persisters. Here, we report multiple individual and complex three-dimensional structures of MqsR and its antitoxin MqsA (B3021), which reveal that MqsR:MqsA form a novel toxin:antitoxin (TA) pair. MqsR adopts an α/ÎČ fold that is homologous with the RelE/YoeB family of bacterial ribonuclease toxins. MqsA is an elongated dimer that neutralizes MqsR toxicity. As expected for a TA pair, MqsA binds its own promoter. Unexpectedly, it also binds the promoters of genes important for E. coli physiology (e.g., mcbR, spy). Unlike canonical antitoxins, MqsA is also structured throughout its entire sequence, binds zinc and coordinates DNA via its C- and not N-terminal domain. These studies reveal that TA systems, especially the antitoxins, are significantly more diverse than previously recognized and provide new insights into the role of toxins in maintaining the persister state

    Autoantibodies against type I IFNs in patients with life-threatening COVID-19

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    Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men

    Lichens and allied fungi of two Regional Parks in Vilnius area (Lithuania)

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    T wo Regional Parks – Verkiai and Pavilniai are situated in Vilnius city area comprising territories both of the city itself and Vilnius district and are under strong anthropogenic influence. During the present study 172 species of lichens, lichenicolous and saprobic fungi were revealed in Verkiai RP and 92 species – in Pavilniai RP. Three lichen species – Absconditella pauxilla, Thelenella pertusariella (in Verkiai RP), Bacidia caligans (in Pavilniai RP) and one saprobic fungus – Chaenothecopsis debilis (in Verkiai RP) are reporded for the first time in Lithuania. Seven lichen species of Lithuanian Red Data Book were recorded, all of them only in Verkiai RP; this indicates less strong anthropogenic impact and better conditions for biodiversity in this Park

    Porosty sƂabo poznanych siedlisk na niĆŒu Europy ƚrodkowo - Wschodniej i Wschodniej

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    Situation of lichens of aquatic and transient habitats in Eastern and East-Central European lowlands is discussed basing on example of several selected species: Leptogium biatorinum, Sarcosagium campestre, Steinia geophana, Verrucaria aquatilis, V. hydrela, V. praetermissa, V. xyloxena. Both habitat types are generally very much neglected in the region and all species show large spatial gaps in recording, which makes it difficult to judge both about their true distribution limits and spreading dynamics. On the other hand, targeted search through the suitable habitats and abundance of such indicate that many of these lichens are probably not uncommon in the region.W pracy przedstawiono rozmieszczenie, frekwencję i stopieƄ zbadania porostĂłw siedlisk wodnych i krĂłtkotrwaƂych w obrębie strefy leƛnej niĆŒu Europy ƚrodkowo-Wschodniej i Wschodniej: Polski, Litwy, Ɓotwy, Estonii i BiaƂorusi oraz Ukrainy i europejskiej częƛci Rosji. Oba typy siedlisk są bardzo sƂabo rozpoznane w tej częƛci Europy. Zagadnienie to omĂłwiono na przykƂadzie wybranych gatunkĂłw efemerycznych: Leptogium biatorinum, Sarcosagium campestre, Steinia geophanai Verrucaria xyloxenaoraz wodnych: Verrucaria aquatilis, V. hydrala i V. praetermissa. W skali wielkoprzestrzennej widoczne są luki w rozmieszczeniu badanych gatunkĂłw (Figs 1-7). Ustalenie ich rzeczywistego rozmieszczenia i dynamiki rozprzestrzenienia jest, jak na razie, trudne. Celowe poszukiwanie odpowiednich siedlisk i charakterystycznych im gatunkĂłw sygnalizuje, ĆŒe mogą one być nawet częste w regionie
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