172,827 research outputs found
Leaf metabolome in arbuscular mycorrhizal symbiosis
No full textSchweiger R, Müller C. Leaf metabolome in arbuscular mycorrhizal symbiosis. Current Opinion in Plant Biology. 2015;26:120-126
Arbuscular mycorrhiza-induced shifts in foliar metabolism and photosynthesis mirror the developmental stage of the symbiosis and are only partly driven by improved phosphate uptake
No full textSchweiger R, Baier MC, Müller C. Arbuscular mycorrhiza-induced shifts in foliar metabolism and photosynthesis mirror the developmental stage of the symbiosis and are only partly driven by improved phosphate uptake. Molecular Plant-Microbe Interactions. 2014;27(12):1403-1412
Impact of growth and uptake patterns of arbuscular mycorrhizal fungi on plant phosphorus uptake—a modelling study
No full textIn this paper we present a mathematical model for estimating external mycelium growth of arbuscular mycorrhizal fungi and its effect on root uptake of phosphate (P). The model describes P transport in soil and P uptake by both root and fungi on the single root scale. We investigate differences in soil P depletion and overall P influx into a mycorrhizal root by assuming that different spatial regions of mycelia are active in P uptake.When all external hyphae contribute to P uptake, overall uptake is dominated by the fungus and the most effective growth pattern appears to be the one using a high level of anastomosis. The same is true when only the proportion of external hyphae assumed to be active contributes to uptake. When uptake is restricted to the tips, hyphal contribution to overall P uptake is less dominant; the most effective growth pattern appears to be the one characterised by nonlinear branching where branching stops at a given maximal hyphal tip density. Comparison to measured P depletion in the literature suggests that the scenario where active hyphae are contributing to P uptake is likely to fit the data best. These quantitative predictions promote our understanding of the mycorrhizal symbiosis and its role in plant P nutrition
Glaphyrus (Glaphyrus) cinnaberinus SCHWEIGER 1949
No full text<i>Glaphyrus</i> (<i>Glaphyrus</i>) <i>cinnaberinus</i> SCHWEIGER, 1949 <p>D i s t r i b u t i o n i n I r a n: Kermanshan(SCHWEIGER 1949; NIKODÝM & KEITH 2007).</p> <p>G e n e r a l d i s t r i b u t i o n: Endemic to Iran (NIKODÝM & BEZDEK 2016).</p> <p>C o m m e n t s: This species is known only upon the original description and assigned on the basis of it.</p>Published as part of <i>Ghahari, Hassan, Nikodým, Milan & M, Pygopleurus, 2018, An annotated checklist of Glaphyridae (Coleoptera: Scarabaeidae) of Iran, pp. 1171-1193 in Linzer biologische Beiträge 50 (2)</i> on page 1184, DOI: <a href="http://zenodo.org/record/5174099">10.5281/zenodo.5174099</a>
Significant links between photosynthetic capacity, atmospheric CO₂ and the diversification of C₃ plants during the last 80 million years
No full textChanging CO₂ concentrations will continue to affect plant growth with consequences for ecosystem functioning. The adaptive capacity of C₃ photosynthesis to changing CO₂ concentrations is, however, insufficiently investigated so far. Here, we focused on the phylogenetic dynamics of maximum carboxylation rate (Vcmax) and maximum electron transport rate (Jmax)—two key determinants of photosynthetic capacity in C₃ plants—and their relation to deep-time dynamics in species diversification, speciation and atmospheric CO₂ concentrations during the last 80 million years. We observed positive relationships between photosynthetic capacity and species diversification as well as speciation rates. We furthermore observed a shift in the relationships between photosynthetic capacity, evolutionary dynamics and prehistoric CO₂ fluctuations about 30 million years ago. From this, we deduce strong links between photosynthetic capacity and evolutionary dynamics in C₃ plants. We furthermore conclude that low CO₂ environments in prehistory might have changed adaptive processes within the C₃ photosynthetic pathway
Kollektivbiographik
No full textHarders L, Schweiger H. Kollektivbiographik. In: Klein C, ed. Handbuch Biographie. Methoden, Traditionen, Theorien. Stuttgart, Weimar: Metzler; 2009: 194-198
Poverty in Graeco-Roman Philosophy
No full textAncient Greek philosophers mainly dealt with poverty from two different perspectives. The first regards poverty as a form of destitution (ptocheia), an individual condition that is usually beneficial to the path of philosophical research, virtue, and happiness. This perspective dates back to Socrates and it strongly influenced Hellenistic philosophers, in particular the Cynics. The second perspective considers poverty as a form of penia (i.e., the necessity of working to earn a living) and thus a political problem, inasmuch as it represents a threat to social harmony and the political stability of the state. This view regards poverty as closely associated with wealth and wealth distribution within the polis. Philosophers such as Plato and Aristotle (but also some of the Pre-Socratics, such as Archytas of Tarentum) dealt with the problem of the conflictual relations between the rich and the poor. They offered different solutions, including redistribution of property (leading to economic egalitarianism), a regular practice of giving by the wealthy to the poor, regulation of access to offices based on wealth, and even exclusion of the poor from political rule. By contrast, poverty finds only scanty attention in the works of Roman philosophers
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
High specificity in plant leaf metabolic responses to arbuscular mycorrhiza
No full textSchweiger R, Baier M, Persicke M, Müller C. High specificity in plant leaf metabolic responses to arbuscular mycorrhiza. Nature Communications. 2014;5(3886): 3886
- …
