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    Sterol preservation in hypersaline microbial mats 

    Shen, Yan; Thiel, Volker; Suarez-Gonzalez, Pablo; Rampen, Sebastiaan W.; Reitner, Joachim
    Biogeosciences 2020; 17(3) p.649-666
    Microbial mats are self-sustaining benthic ecosystems composed of highly diverse microbial communities. It has been proposed that microbial mats were widespread in Proterozoic marine environments, prior to the emergence of bioturbating organisms at the Precambrian–Cambrian transition. One characteristic feature of Precambrian biomarker records is that steranes are typically absent or occur in very low concentrations. This has been explained by low eukaryotic source inputs, or degradation of primary produced sterols in benthic microbial mats (“mat-seal effect”). To better understand the preservational pathways of sterols in microbial mats, we analyzed freely extractable and carbonate-bound lipid fractions as well as decalcified extraction residues in different layers of a recent calcifying mat (∼1500 years) from the hypersaline Lake 2 on the island of Kiritimati, central Pacific. A variety of C27–C29 sterols and distinctive C31 4α-methylsterols (4α-methylgorgosterol and 4α-methylgorgostanol, biomarkers for dinoflagellates) were detected in freely extractable and carbonate-bound lipid pools. These sterols most likely originated from organisms living in the water column and the upper mat layers. This autochthonous biomass experienced progressive microbial transformation and degradation in the microbial mat, as reflected by a significant drop in total sterol concentrations, up to 98 %, in the deeper layers, and a concomitant decrease in total organic carbon. Carbonate-bound sterols were generally low in abundance compared to the freely extractable portion, suggesting that incorporation into the mineral matrix does not play a major role in the preservation of eukaryotic sterols in this mat. Likewise, pyrolysis of extraction residues suggested that sequestration of steroid carbon skeletons into insoluble organic matter was low compared to hopanoids. Taken together, our findings argue for a major mat-seal effect affecting the distribution and preservation of steroids in the mat studied. This result markedly differs from recent findings made for another microbial mat growing in the nearby hypersaline Lake 22 on the same island, where sterols showed no systematic decrease with depth. The observed discrepancies in the taphonomic pathways of sterols in microbial mats from Kiritimati may be linked to multiple biotic and abiotic factors including salinity and periods of subaerial exposure, implying that caution has to be exercised in the interpretation of sterol distributions in modern and ancient microbial mat settings.
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    Electrochemical Access to Aza-Polycyclic Aromatic Hydrocarbons: Rhoda-Electrocatalyzed Domino Alkyne Annulations 

    Kong, Wei-Jun; Shen, Zhigao; Finger, Lars H.; Ackermann, Lutz
    Angewandte Chemie International Edition(59) p.1-7
    Nitrogen-doped polycyclic aromatic hydrocarbons (aza-PAHs) have found broad applications in material sciences. Herein, a modular electrochemical synthesis of aza-PAHs was developed via a rhodium-catalyzed cascade C-H activation and alkyne annulation. A multifunctional O-methylamidoxime enabled the high chemo- and regioselectivity. The isolation of two key rhodacyclic intermediates made it possible to delineate the exact order of three C-H activation steps. In addition, the metalla-electrocatalyzed multiple C-H transformation is characterized by unique functional group tolerance, including highly reactive iodo and azido groups.
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    Generic parameters of first-order kinetics accurately describe soil organic matter decay in bare fallow soils over a wide edaphic and climatic range 

    Menichetti, Lorenzo; Ågren, Göran I.; Barré, Pierre; Moyano, Fernando; Kätterer, Thomas
    Scientific Reports 2019; 9(1): Art. 20319
    The conventional soil organic matter (SOM) decay paradigm considers the intrinsic quality of SOM as the dominant decay limitation with the result that it is modelled using simple first-order decay kinetics. This view and modelling approach is often criticized for being too simplistic and unreliable for predictive purposes. It is still under debate if first-order models can correctly capture the variability in temporal SOM decay observed between different agroecosystems and climates. To address this question, we calibrated a first-order model (Q) on six long-term bare fallow field experiments across Europe. Following conventional SOM decay theory, we assumed that parameters directly describing SOC decay (rate of SOM quality change and decomposer metabolism) are thermodynamically constrained and therefore valid for all sites. Initial litter input quality and edaphic interactions (both local by definition) and microbial efficiency (possibly affected by nutrient stoichiometry) were instead considered site-specific. Initial litter input quality explained most observed kinetics variability, and the model predicted a convergence toward a common kinetics over time. Site-specific variables played no detectable role. The decay of decades-old SOM seemed mostly influenced by OM chemistry and was well described by first order kinetics and a single set of general kinetics parameters.
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    Microtiming Deviations and Swing Feel in Jazz 

    Datseris, George; Ziereis, Annika; Albrecht, Thorsten; Hagmayer, York; Priesemann, Viola; Geisel, Theo
    Scientific Reports 2019; 9(1): Art. 19824
    Jazz music that swings has the fascinating power to elicit a pleasant sensation of flow in listeners and the desire to synchronize body movements with the music. Whether microtiming deviations (MTDs), i.e. small timing deviations below the bar or phrase level, enhance the swing feel is highly debated in the current literature. Studies on other groove related genres did not find evidence for a positive impact of MTDs. The present study addresses jazz music and swing in particular, as there is some evidence that microtiming patterns are genre-specific. We recorded twelve piano jazz standards played by a professional pianist and manipulated the natural MTDs of the recordings in systematic ways by quantizing, expanding and inverting them. MTDs were defined with respect to a grid determined by the average swing ratio. The original and manipulated versions were presented in an online survey and evaluated by 160 listeners with various musical skill levels and backgrounds. Across pieces the quantized versions (without MTDs) were rated slightly higher and versions with expanded MTDs were rated lower with regard to swing than the original recordings. Unexpectedly, inversion had no impact on swing ratings except for two pieces. Our results suggest that naturally fluctuating MTDs are not an essential factor for the swing feel.
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    FXD-CSD-GUI : a graphical user interface for the X-ray-diffraction-based determination of crystallite size distributions 

    Neher, Sigmund H.; Klein, Helmut; Kuhs, Werner F.
    Journal of Applied Crystallography 2019; 52(6) p.1437-1439
    Bragg intensities can be used to analyse crystal size distributions in a method called FXD-CSD, which is based on the fast measurement of many Bragg spots using two-dimensional detectors. This work presents the Python-based software and its graphical user interface FXD-CSD-GUI. The GUI enables user-friendly data handling and processing and provides both graphical and numerical crystal size distribution results.
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    The Unfolded Protein Response Regulates Pathogenic Development of Ustilago maydis by Rok1-Dependent Inhibition of Mating-Type Signaling 

    Schmitz, Lara; Schwier, Melina Ayaka; Heimel, Kai
    Scientific Reports 2019; 10(6): Art. 20319
    The conventional soil organic matter (SOM) decay paradigm considers the intrinsic quality of SOM as the dominant decay limitation with the result that it is modelled using simple first-order decay kinetics. This view and modelling approach is often criticized for being too simplistic and unreliable for predictive purposes. It is still under debate if first-order models can correctly capture the variability in temporal SOM decay observed between different agroecosystems and climates. To address this question, we calibrated a first-order model (Q) on six long-term bare fallow field experiments across Europe. Following conventional SOM decay theory, we assumed that parameters directly describing SOC decay (rate of SOM quality change and decomposer metabolism) are thermodynamically constrained and therefore valid for all sites. Initial litter input quality and edaphic interactions (both local by definition) and microbial efficiency (possibly affected by nutrient stoichiometry) were instead considered site-specific. Initial litter input quality explained most observed kinetics variability, and the model predicted a convergence toward a common kinetics over time. Site-specific variables played no detectable role. The decay of decades-old SOM seemed mostly influenced by OM chemistry and was well described by first order kinetics and a single set of general kinetics parameters.
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    Two new ant species (Formicidae: Dorylinae, Ponerinae) from New Caledonia 

    Ramage, Thibault; Jouault, Corentin; Schmidt, Alexander R.; Seyfullah, Leyla J.; Perrichot, Vincent
    European Journal of Taxonomy(589) p.1-14
    Two new species of ants (Hymenoptera: Formicidae) collected from New Caledonia are described and figured based on worker specimens: Leptogenys loarelae Ramage sp. nov. (Ponerinae, Ponerini) and Lioponera neocaledonica Jouault, Ramage & Perrichot sp. nov. (Dorylinae, Cerapachyini). All specimens were collected from the South Province of Grande Terre. These two new species are primarily distinguished from the other New Caledonian relatives by the size and shape of petiole for L. loarelae Ramage sp. nov. and by the presence of dorsolateral margins on the mesosoma for L. neocaledonica Jouault, Ramage & Perrichot sp. nov. Keys to New Caledonian Leptogenys and Lioponera are provided.
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    A numerical sensitivity study of how permeability, porosity, geological structure, and hydraulic gradient control the lifetime of a geothermal reservoir 

    Bauer, Johanna F.; Krumbholz, Michael; Luijendijk, Elco; Tanner, David C.
    Solid Earth 2019; 10(6) p.2115-2135
    Geothermal energy is an important and sustainable resource that has more potential than is currently utilized. Whether or not a deep geothermal resource can be exploited, mostly depends on, besides temperature, the utilizable reservoir volume over time, which in turn largely depends on petrophysical parameters. We show, using over 1000 (n=1027) 4-D finite-element models of a simple geothermal doublet, that the lifetime of a reservoir is a complex function of its geological parameters, their heterogeneity, and the background hydraulic gradient (BHG). In our models, we test the effects of porosity, permeability, and BHG in an isotropic medium. Furthermore, we simulate the effect of permeability contrast and anisotropy induced by layering, fractures, and a fault. We quantify the lifetime of the reservoir by measuring the time to thermal breakthrough, i.e. how many years pass before the temperature of the produced fluid falls below the 100 ∘C threshold. The results of our sensitivity study attest to the positive effect of high porosity; however, high permeability and BHG can combine to outperform the former. Particular configurations of all the parameters can cause either early thermal breakthrough or extreme longevity of the reservoir. For example, the presence of high-permeability fractures, e.g. in a fault damage zone, can provide initially high yields, but it channels fluid flow and therefore dramatically restricts the exploitable reservoir volume. We demonstrate that the magnitude and orientation of the BHG, provided permeability is sufficiently high, are the prime parameters that affect the lifetime of a reservoir. Our numerical experiments show also that BHGs (low and high) can be outperformed by comparatively small variations in permeability contrast (103) and fracture-induced permeability anisotropy (101) that thus strongly affect the performance of geothermal reservoirs.
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    What Difference Does Public Participation Make? An Alternative Futures Assessment Based on the Development Preferences for Cultural Landscape Corridor Planning in the Silk Roads Area, China 

    Xu; Plieninger; Zhao; Primdahl
    Sustainability 2019; 11(22): Art. 6525
    Landscape corridor planning (LCP) has become a widespread practice for promoting sustainable regional development. This highly complex planning process covers many policy and planning issues concerning the local landscape, and ideally involves the people who live in the area to be developed. In China, regional planners and administrators encourage the development of landscape corridor planning. However, the current LCP process rarely considers ideas from local residents, and public participation is not recognized as beneficial to planning outcomes. We use a specific Chinese case of LCP to analyze how citizen involvement may enrich sustainable spatial planning in respect to ideas considered and solutions developed. To this end, we compare a recently approved landscape corridor plan that was created without public participation with alternative solutions for the same landscape corridor, developed with the involvement of local residents. These alternatives were then evaluated by professional planners who had been involved in the initial planning process. We demonstrate concrete differences between planning solutions developed with and without public participation. Further, we show that collaborative processes can minimize spatial conflicts. Finally, we demonstrate that public participation does indeed contribute to innovations that could enrich the corridor plan that had been produced exclusively by the decision-makers. The paper closes with a discussion of difficulties that might accompany the involvement of local residents during sustainable LCP in China.
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    Impact Assessment of Timber Harvesting Operations for Enhancing Sustainable Management in a Secondary Atlantic Forest 

    Britto, Pedro C.; Jaeger, Dirk; Hoffmann, Stephan; Robert, Renato C. G.; Vibrans, Alexander C.; Fantini, Alfredo C.
    Sustainability 2019; 11(22): Art. 6272
    Conservation and management of forest ecosystems are currently largely conflicting goals in the Brazilian Atlantic Forest biome. At present, all parts of the Atlantic Forest are protected and commercial logging is highly restricted. However, sustainable forest management systems can offer significant income opportunities for landholders, and thereby actively support the process of ecosystem rehabilitation and protection of the Atlantic Forest. This research is intended to contribute to enhancing the development of environmentally sound forest management alternatives in the Atlantic Forest biome. Through a case study, the harvesting impact of a conventional harvesting method (CM) was evaluated and compared with an alternative and improved harvesting method (AM), performed by a well-trained professional chainsaw operator experienced in reduced impact logging techniques, and included the use of a snatch block and a skidding cone. Following a full pre-harvest inventory, 110 different tree species were identified. The harvesting impact on the residual stand was classified and evaluated through a successive post-harvest inventory. Damage maps were developed based on interpolation of tree damage intensities with the triangular irregular networks (TIN) methodology. Our results showed noticeable high rates of tree hang-ups, observed for both harvesting methods. Furthermore, the harvesting damaged trees mainly in the lower diameter at breast height (DBH) classes. In comparison to winching, the felling process caused most of the damage to remnant trees for both methods, at 87% (CM) and 88% (AM). The number of damaged trees (above 11.9 cm DBH) per harvested tree, for CM, ranged from 0.8 trees to 2.5 trees and, for AM, ranged from 0.6 trees to 2.2 trees. Improvements of the AM method (operator skills, skidding cone and snatch block) over CM allowed for a reduction of the damaged basal area, a reduction of the “high damaged area” per plot, and a reduction of the winching disturbed ground area. Nonetheless, a suitable harvesting system should consider further improvements in the felling technique, and additionally integrate the local knowledge of CM regarding forest and tree species with the technical improvements of AM.
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    Effects of political instability on the volatility of Palestinian food prices 

    Ihle, Rico; El-Jafari, Mahmoud Khader; von Cramon-Taubadel, Stephan
    New Medit 2019; 18(3) p.59-76
    Political instabilities and violent political conflict have in recent years risen substantially throughout the world. Especially in the Middle East and North Africa they have grown to decisive factors permanently challenging the livelihoods of millions. We assess whether and to what extent varying intensities of conflict impact economic activity in Palestine which has been subject to substantial violent political conflict for decades. In particular, we analyse the relationship between various intensity levels of political instability measured by conflict-caused fatalities and uncertainty of weekly food prices in the West Bank between 2004 and 2011 using a GARCH model. We consider four food commodities covering vegetables, fruits and animal products. Banana and milk prices are found not to show clustered volatility while onion and pear prices do. The impact of varying conflict intensities on weekly average prices appears to be modest. This might suggest that effects happen on a temporally and geographically more disaggregated scale.
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    Insect conservation in agricultural landscapes: An outlook for policy-relevant research 

    Mupepele, Anne-Christine; Böhning-Gaese, Katrin; Lakner, Sebastian; Plieninger, Tobias; Schoof, Nicolas; Klein, Alexandra-Maria
    GAIA - Ecological Perspectives for Science and Society 2019; 28(4) p.342-347
    Insect populations decline, particularly in intensively managed agricultural landscapes. Insect communities are influenced by current agricultural practices, which are themselves determined by the economic, political and social frameworks. We highlight these direct and indirect drivers affecting insect communities, raise key research questions and discuss options for action to encourage a transformative change towards an economic, political and social system protecting biodiversity.
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    Evolutionary transitions toward pair living in nonhuman primates as stepping stones toward more complex societies 

    Kappeler, Peter M.; Pozzi, Luca
    Science Advances 2019; 5(12): Art. eaay1276
    Nonhuman primate societies vary tremendously in size and composition, but how and why evolutionary transitions among different states occurred remains highly controversial. In particular, how many times pair living evolved and the social states of the ancestors of pair- and group-living species remains contentious. We examined evolutionary transitions in primate social evolution by using new, independent categorizations of sociality and different phylogenetic hypotheses with a vastly expanded dataset. Using Bayesian phylogenetic comparative methods, we consistently found the strongest support for a model that invokes frequent transitions between solitary ancestors and pair-living descendants, with the latter giving rise to group-living species. This result was robust to systematic variation in social classification, sample size, and phylogeny. Our analyses therefore indicate that pair living was a stepping stone in the evolution of structurally more complex primate societies, a result that bolsters the role of kin selection in social evolution.
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    How to Achieve Tax Compliance by the Wealthy: A Review of the Literature and Agenda for Policy 

    Gangl, Katharina; Torgler, Benno
    Social Issues and Policy Review 2019; 14(1) p.108-151
    Tax compliance by the wealthy is relevant not only because their contributions are essential to maintain public budgets and social equality, but because their (non)compliance behavior and the perceived (un)fairness of their contributions can fuel social unrest. In this article, after giving a brief history of taxing the wealthy, we review the existing theoretical, empirical, and policy literature on their tax compliance. We discuss how and why the wealthy differ from less affluent taxpayers because of specific interrelated political, social, and psychological conditions. Understanding the psychological mechanisms that determine the tax compliance of the wealthy can provide policy insights on how to better integrate the wealthy in the tax system. Therefore, the present review is also a starting point for new policy approaches to increase tax compliance and tax morale among the wealthy.
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    Invasive lumbricid earthworms in North America—Different life histories but common dispersal? 

    Klein, Andreas; Eisenhauer, Nico; Schaefer, Ina
    Journal of Biogeography p.1-12
    Aim: Lumbricid earthworms are invasive across northern North America, caus‐ ing notable changes in forest ecosystems. During their range expansion, they en‐ countered harsher climatic conditions compared to their native ranges in short time (~400 years). This study investigated if (a) dispersal barriers, (b) climatic selection or (c) anthropogenic activities, that is fishing bait disposal, structure the dispersal of free‐living earthworm populations. Location: North America, forest habitats along former Wisconsinan glaciation line. Taxon: Lumbricus terrestris, L. rubellus. Methods: Lumbricus terrestris and L. rubellus co‐occur in the same habitats but dif‐ fer in ecology and use as fishing bait. Both species were sampled in five transects ranging from the east to the west coast of northern North America, including major dispersal barriers, three different climate zones, and bait shops near sampling loca‐ tions. Genetic diversity and structure were compared between the two species, and the presence of free‐living bait shop genotypes was assessed using four markers (COI, 16S rDNA, 12S rDNA, and H3). Results: Populations of both species were genetically diverse with some geographic structure, which was more pronounced in L. terrestris than in L. rubellus. Common haplotypes were present in all regions, but locally restricted haplotypes also oc‐ curred. Furthermore, two distinct genetic clades of L. terrestris co‐occurred only in the two most distant transects (Alberta and Minnesota). Genotypes identical to bait individuals were omnipresent in field populations of L. terrestris. Main Conclusions: Genetic diversity was high in both species, and invasive popula‐ tions represented a genetic subset of European earthworms. Geographic and climatic dispersal barriers affected the less mobile species, L. terrestris, resulting in differ‐ ences in genetic structure between the two species. Our results indicate common long‐distance dispersal vectors and vectors affecting only L. terrestris. The roles of climate and anthropogenic activities are discussed, providing additional explanations of dispersal and new insights into establishment of invasive earthworm populations.
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    Time-evolution methods for matrix-product states 

    Paeckel, Sebastian; Köhler, Thomas; Swoboda, Andreas; Manmana, Salvatore R.; Schollwöck, Ulrich; Hubig, Claudius
    Annals of Physics 2019; 411: Art. 167998
    Matrix-product states have become the de facto standard for the representation of one-dimensional quantum many body states. During the last few years, numerous new methods have been introduced to evaluate the time evolution of a matrix-product state. Here, we will review and summarize the recent work on this topic as applied to finite quantum systems. We will explain and compare the different methods available to construct a time-evolved matrix-product state, namely the time-evolving block decimation, the MPO method, the global Krylov method, the local Krylov method and the one- and two-site time-dependent variational principle. We will also apply these methods to four different representative examples of current problem settings in condensed matter physics.
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    The number of k-mer matches between two DNA sequences as a function of k and applications to estimate phylogenetic distances 

    Röhling, Sophie; Linne, Alexander; Schellhorn, Jendrik; Hosseini, Morteza; Dencker, Thomas; Morgenstern, Burkhard
    PLOS ONE 2020; 15(2): Art. e0228070
    We study the number Nk of length-k word matches between pairs of evolutionarily related DNA sequences, as a function of k. We show that the Jukes-Cantor distance between two genome sequences—i.e. the number of substitutions per site that occurred since they evolved from their last common ancestor—can be estimated from the slope of a function F that depends on Nk and that is affine-linear within a certain range of k. Integers kmin and kmax can be calculated depending on the length of the input sequences, such that the slope of F in the relevant range can be estimated from the values F(kmin) and F(kmax). This approach can be generalized to so-called Spaced-word Matches (SpaM), where mismatches are allowed at positions specified by a user-defined binary pattern. Based on these theoretical results, we implemented a prototype software program for alignment-free sequence comparison called Slope-SpaM. Test runs on real and simulated sequence data show that Slope-SpaM can accurately estimate phylogenetic distances for distances up to around 0.5 substitutions per position. The statistical stability of our results is improved if spaced words are used instead of contiguous words. Unlike previous alignment-free methods that are based on the number of (spaced) word matches, Slope-SpaM produces accurate results, even if sequences share only local homologies.
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    Polyclad phylogeny persists to be problematic 

    Dittmann, Isabel L.; Cuadrado, Daniel; Aguado, Maria Teresa; Noreña, Carolina; Egger, Bernhard
    Organisms Diversity & Evolution 2019; 19(4) p.585-608
    Two conflicting morphological approaches to polyclad systematics highlight the relevance of molecular data for resolving the interrelationships of Polycladida. In the present study, phylogenetic trees were reconstructed based on a short alignment of the 28S rDNA marker gene with 118 polyclad terminals (24 new) including 100 different polyclad species from 44 genera and 22 families, as well as on a combined dataset using 18S and 28S rDNA genes with 27 polyclad terminals (19 new) covering 26 different polyclad species. In both approaches, Theamatidae and Cestoplanidae were included, two families that have previously been shown to switch from Acotylea to Cotylea. Three different alignment methods were used, both with and without alignment curation by Gblocks, and all alignments were subjected to Bayesian inference and maximum likelihood tree calculations. Over all trees of the combined dataset, an extended majority-rule consensus tree had weak support for Theamatidae and Cestoplanidae as acotyleans, and also the cotylean genera Boninia, Chromyella and Pericelis appeared as acotyleans. With the most inclusive short 28S dataset, on the other hand, there is good support for the aforementioned taxa as cotyleans. Especially with the short 28S matrix, taxon sampling, outgroup selection, alignment method and curation, as well as model choice were all decisive for tree topology. Well-supported parts of the phylogeny over all trees include Pseudocerotoidea, Prosthiostomoidea, Stylochoidea, Leptoplanoidea and Cryptoceloidea, the latter three with new definitions. Unstable positions in the tree were found not only for Theamatidae, Cestoplanidae, Boninia, Chromyella and Pericelis, but also for Anonymus, Chromoplana and Cycloporus.
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    Back to the future: rethinking socioecological systems underlying high nature value farmlands 

    Lomba, Angela; Moreira, Francisco; Klimek, Sebastian; Jongman, Robert H. G.; Sullivan, Caroline; Moran, James; Poux, Xavier; Honrado, João P.; Pinto‐Correia, Teresa; Plieninger, Tobias; et al.
    McCracken, David I.
    Frontiers in Ecology and the Environment 2019; 18(1) p.36-42
    Farmlands are currently among the dominant uses of the land. When managed under low‐input farming systems, farmlands are associated with diverse cultural and natural heritages around the world. Known in Europe as high nature value (HNV) farmlands, these agricultural landscapes and their associated farming systems evolved as tightly coupled socioecological systems, and are essential to biodiversity conservation and the delivery of ecosystem services to society. However, HNV farmlands are vulnerable to socioeconomic changes that lead to either agricultural intensification or land abandonment. We present a range of plausible future scenarios for HNV farmlands, and discuss the related management options and expected socioecological outcomes for each scenario. We then provide recommendations for policy, practice, and research on how to best ensure the socioecological viability of HNV farming systems in the future.
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    Cytoplasmic retention and degradation of a mitotic inducer enable plant infection by a pathogenic fungus 

    Bardetti, Paola; Castanheira, Sónia Marisa; Valerius, Oliver; Braus, Gerhard H; Pérez-Martín, José
    eLife 2019; 8: Art. e48943
    In the fungus Ustilago maydis, sexual pheromones elicit mating resulting in an infective filament able to infect corn plants. Along this process a G2 cell cycle arrest is mandatory. Such as cell cycle arrest is initiated upon the pheromone recognition in each mating partner, and sustained once cell fusion occurred until the fungus enter the plant tissue. We describe that the initial cell cycle arrest resulted from inhibition of the nuclear transport of the mitotic inducer Cdc25 by targeting its importin, Kap123. Near cell fusion to take place, the increase on pheromone signaling promotes Cdc25 degradation, which seems to be important to ensure the maintenance of the G2 cell cycle arrest to lead the formation of the infective filament. This way, premating cell cycle arrest is linked to the subsequent steps required for establishment of the infection. Disabling this connection resulted in the inability of fungal cells to infect plants.
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