Editorial: Essential Biomolecules Caught in the Food Web?

Peer Reviewe

Reversal of density dependence of juvenile Littorina littorea (Gastropoda) growth in response to periphyton nutrient status

Experimental periphyton communities were grown in aquaria receiving media of differently enriched seawater (fully enriched, without Si enrichment, without N and P enrichment) and supplied differently with medium (batch and weekly replacement). Periphyton was subject to grazing by 1-6 individuals of juvenile Littorina littorea. Periphyton biomass was higher in the replacement aquaria than in the batch aquaria and higher in the full and the -Si medium than in the -NP medium. The N:C ratio of the periphyton increased with Littorina number in the batch aquaria and was unaffected by Littorina number in the replacement aquaria. Diatoms were most dominant in the -NP treatments and rarest in the -Si treatments. Chlorophytes were dominant in the -Si and the fully enriched treatments, but also Cyanobacteria contributed significantly to periphyton biomass in those treatments under nutrient replacement. Somatic growth of Littorina was negatively correlated to Littorina density in the replacement aquaria and positively density dependent in the batch aquaria. The latter is explained by improved food quality under stronger grazing pressure

Modelling the extreme storm surge in the western Baltic Sea on November 13, 1872, revisited

Die Küste, 92 - Online First - 1872 - An exceptional storm surge in the Balti

Charmonium - Pion Cross Section from QCD Sum Rules

The $J/\psi \pi\to \bar{D} D^*, \bar{D} D$, ${\bar D}^* D^*$ and ${\bar D} D^*$ cross sections as a function of $\sqrt{s}$ are evaluated in a QCD sum rule calculation. We study the Borel sum rule for the four point function involving pseudoscalar and vector meson currents, up to dimension four in the operator product expansion. We find that our results are smaller than the $J/\psi \pi\to {charmed mesons}$ cross sections obtained with models based on meson exchange, but are close to those obtained with quark exchange models.Comment: revised version accepted for publication in Phys. Lett.

New disease on red flowering horse chestnut (Aesculus x carnea Hayne) and the molecular identification of the involved pathogens

In dieser Studie wurde eine in Nord-West Deutschland bisher nicht bekannte Krankheit der Rotblühenden Rosskastanie (Aesculus × carnea Hayne) untersucht. Die Krankheit ist durch Fruchtkörper der Weißfäulepilze Flammulina velutipes (Curtis) Singer und Pleurotus ostreatus (Jacq. ex Fr.) Kummer, die Stämmlings- und Astabbrüche verur­sachen, einer Infektion mit Pseudomonas syringae pv. aesculi und Rindenrisse charakterisiert. Um die Hauptverursacher der Krankheit zu identifizieren, wurden vier Stammscheiben von zwei erkrankten Rotblühenden Rosskastanien untersucht und über den Querschnitt in Probenbereiche aufgeteilt. Die Untersuchung der einzelnen Gewebebereiche ermöglicht es, die Schadorganismen ihrer Rolle im Schadverlauf zuzuordnen. Durch die Sequenzierung der ITS Region der rDNA wurden vier Weißfäule­pilze F. velutipes, P. ostreatus, sowie Bjerkandera adusta (Willd. ex Fr.) Karst. und Chondrostereum purpureum (Pers. ex Fr.) Pouzar und einige Ascomyceten identifiziert. Die Verteilung der Pilze über den Querschnitt der Stammscheiben lässt es zu, diese als die Hauptverursacher des Schadens zu charakterisieren und diesen als Komplexkrankheit zu beschreiben.In dieser Studie gelang der Nachweis von mehreren Basidiomyceten in einem Gewebe, was die Komplexität der Krankheit unterstreicht. Zudem wird F. velutipes zum ersten Mal molekular als Parasit an der Rotblühenden Rosskastanie beschrieben und Pseudomonas syringae pv. aesculi erstmals sowohl im inneren Phloem als auch im sekundären Xylem von natürlich infizierten Rotblühenden Rosskastanien nachgewiesen. DOI: 10.5073/JfK.2014.12.03, https://doi.org/10.5073/JfK.2014.12.03A so far unknown disease which is found on red flowering horse chestnut (Aesculus × carnea Hayne) in the north-west of Germany has been investigated. It is characterized by the presence of fruiting bodies of Flammulina velutipes (Curtis) Singer and Pleurotus ostreatus (Jacq. ex Fr.) Kummer, able to cause breakage of branches and stems by white rot. Additional infection by Pseudomonas syringae pv. aesculi, and cracks of the bark are found.To get detailed knowledge of the disease, samples were taken from cross sections of four decayed red flowering horse chestnut stems. The investigation of individual tissues across the stem enables the assignment of the pathogens to the new disease. Sequencing of the rDNA-ITS identified F. velutipes and P. ostreatus, Bjerkandera adusta (Willd. ex Fr.) Karst. and Chondrostereum purpureum (Pers. ex Fr.) Pouzar, four white rot fungi, as main pathogens and some ascomycetes in the infected and decaying stem tissues.Our studies revealed the co-appearance of different basidiomycetes and ascomycetes in decaying tissue zones which emphasizes the complexity of the disease. It is also the first proof of involvement of F. velutipes as a parasite on red flowering horse chestnut. In addition, for the first time, Pseudomonas syringae pv. aesculi was detected in the inner bark and within the secondary xylem of natural infected red flowering horse chestnut. DOI: 10.5073/JfK.2014.12.03, https://doi.org/10.5073/JfK.2014.12.0

Late Eocene to middle Miocene (33 to 13 million years ago) vegetation and climate development on the North American Atlantic Coastal Plain (IODP Expedition 313, Site M0027)

ArticleWe investigated the palynology of sediment cores from Site M0027 of IODP (Integrated Ocean Drilling Program) Expedition 313 on the New Jersey shallow shelf to examine vegetation and climate dynamics on the east coast of North America between 33 and 13 million years ago and to assess the impact of over-regional climate events on the region. Palynological results are complemented with pollen-based quantitative climate reconstructions. Our results indicate that the hinterland vegetation of the New Jersey shelf was characterized by oak–hickory forests in the lowlands and conifer-dominated vegetation in the highlands from the early Oligocene to the middle Miocene. The Oligocene witnessed several expansions of conifer forest, probably related to cooling events. The pollen-based climate data imply an increase in annual temperatures from ∼11.5 °C to more than 16 °C during the Oligocene. The Mi-1 cooling event at the onset of the Miocene is reflected by an expansion of conifers and mean annual temperature decrease of ∼4 °C, from ∼16 °C to ∼12 °C around 23 million years before present. Relatively low annual temperatures are also recorded for several samples during an interval around ∼20 million years before present, which may reflect the Mi-1a and the Mi-1aa cooling events. Generally, the Miocene ecosystem and climate conditions were very similar to those of the Oligocene. Miocene grasslands, as known from other areas in the USA during that time period, are not evident for the hinterland of the New Jersey shelf, possibly reflecting moisture from the proto-Gulf Stream. The palaeovegetation data reveal stable conditions during the mid-Miocene climatic optimum at ∼15 million years before present, with only a minor increase in deciduous–evergreen mixed forest taxa and a decrease in swamp forest taxa. Pollen-based annual temperature reconstructions show average annual temperatures of ∼14 °C during the mid-Miocene climatic optimum, ∼2 °C higher than today, but ∼1.5 °C lower than preceding and following phases of the Miocene. We conclude that vegetation and regional climate in the hinterland of the New Jersey shelf did not react as sensitively to Oligocene and Miocene climate changes as other regions in North America or Europe due to the moderating effects of the North Atlantic. An additional explanation for the relatively low regional temperatures reconstructed for the mid-Miocene climatic optimum could be an uplift of the Appalachian Mountains during the Miocene, which would also have influenced the catchment area of our pollen record.We thank the entire IODP Expedition 313 Scientific Party for input, and the IODP staff for support. We thank M. Drljepan, R. Zanatta, V. Menke, K. Reichel, and S. Namyslo for their assistance with preparing and processing the samples, and during photographing. Discussions with C. Bjerrum, J. Browning, T. Donders, L. Fang, M. Katz, Y. Milker, K. Miller, and P. Sugarman are gratefully acknowledged. Input from K. Dybkjær and anonymous reviewers was very much appreciated and contributed to a significant condensing of the manuscript. The German Science Foundation supported the research (DFG project KO 3944/3-1 to U. Kotthoff). Funding was also provided by NSERC Discovery Grants to F. M. G. McCarthy and to D. R. Greenwood respectively. NERC supported work by S. P. Hesselbo. This research used samples and/or data provided by the Integrated Ocean Drilling Program (IODP)