Stabilisation of precipitates of pedogenic dissolved organic matter by multivalent cations

Purpose Precipitation of dissolved organic matter (DOM) by multivalent cations is important for biogeochemical cycling of organic carbon. We investigated to which extent cation bridges are involved in DOM precipitation and how cross-links by cations and water molecule bridges (WaMB) stabilise the matrix of precipitated DOM. Materials and methods DOM was precipitated from the aqueous extract of a forest floor layer adding solutions of Ca(NO3)2, Al(NO3)3 and Pb(NO3)2 with different initial metal cation/C (Me/C) ratios. Precipitates were investigated by differential scanning calorimetry before and after ageing to detect cation bridges, WaMB and restructuring of supramolecular structure. Results and discussion Twenty-five to sixty-seven per cent of the dissolved organic carbon was precipitated. The precipitation efficiency of cations increased in the order Ca < Al < Pb, while the cation content of precipitates increased in the order Pb < Ca < Al. The different order and the decrease in the WaMB transition temperature (T*) for Al/C > 3 is explained by additional formation of small AlOOH particles. Thermal analysis indicated WaMB and their disruption at T* of 53–65 °C. Like cation content, T* increased with increasing Me/C ratio and in the order Ca < Pb < Al for low Me/C. This supports the general assumption that cross-linking ability increases in the order Ca < Pb < Al. The low T* for high initial Me/C suggests less stable and less cross-linked precipitates than for low Me/C ratios. Conclusions Our results suggest a very similar thermal behaviour of OM bound in precipitates compared with soil organic matter and confirms the relevance of WaMB in stabilisation of the supramolecular structure of cation-DOM precipitates. Thus, stabilisation of the supramolecular structure of the DOM precipitates is subjected to dynamics in soils.

Der Blitz : Oper in drei Aufzügen

Musik von Halevy. Nach dem Franz. von Friederike Elmenreich

Der Kreuzritter in Egypten : heroische Oper in 2 Aufzügen

Musik von Mayerbeer. Nach dem Italien. von Friederike Elmenreich

Amino Acid Export in Developing Arabidopsis Seeds Depends on UmamiT Facilitators

Essential amino acids cannot be synthesized by humans and animals. They often are limiting in plant-derived foods and determine the nutritional value of a given diet [1]. Seeds and fruits often represent the harvestable portion of plants. In order to improve the amino acid composition of these tissues, it is indispensable to understand how these substrates are transported within the plant. Amino acids result from nitrogen assimilation, which often occurs in leaves, the source tissue. They are transported via the vasculature, the xylem, and the phloem into the seeds, the so-called sink tissue, where they are stored or consumed. In seeds, several tissues are symplasmically isolated [2, 3], i.e., not connected by plasmodesmata, channels in the cell walls that enable a cytoplasmic continuum in plants [4]. Consequently, amino acids must be exported from cells into the apoplast and re-imported many times to support seed development. Several amino acid importers are known, but exporters remained elusive [5, 6]. Here, we characterize four members of the plant-specific UmamiT transporter family from Arabidopsis, related to the amino acid facilitator SIAR1 and the vacuolar auxin transporter WAT1 [7, 8]. We show that the proteins transport amino acids along their (electro)chemical potential across the plasma membrane. In seeds, they are found in tissues from which amino acids are exported. Loss-of-function mutants accumulate high levels of free amino acids in fruits and produce smaller seeds. Our results strongly suggest a crucial role for the UmamiTs in amino acid export and possibly a means to improve yield quality.

Cognitive effects of masculine generics in German. An overview of empirical findings

This article presents a series of experiments which were conducted among native speakers of German to determine the influence of different types of German generics on the cognitive inclusion of women. Results indicate that the inclusion of women is higher with ‘non-sexist’ alternatives than with masculine generics, a tendency which was consistent across different studies. The different alternatives, however, showed different effects which also varied depending on the context. These results are discussed with regard to their practical consequences in situations such as nominating women and men for awards or political offices.

Name your favorite musician: Effects of masculine generics and of their alternatives in German

Feminist linguists claim that masculine forms used in a generic sense (e.g. he referring to a doctor irrespective of sex) facilitate the cognitive representation of men compared to women and make women less visible. A number of experimental studies have confirmed this assumption with regard to the English language. Concerning other languages, however, this question has been addressed only in very few studies, although gender is a much more pervasive grammatical category and masculine generics are more prominent in languages such as French, Spanish or German. This paper reports three experiments with native speakers of German which were conducted to determine the influence of different types of German generics on the cognitive inclusion of women. Results indicate that inclusion of women is higher with 'non-sexist' alternatives than with masculine generics, a tendency which was consistent over studies. But the different alternative forms show different effects which also vary depending on the context. These results are discussed with regard to their practical consequences in situations such as nominating women and men for awards, political offices etc.

Früherkennung und integrierte Versorgung von Jugendlichen und jungen Erwachsenen mit schweren psychotischen Erkrankungen

Prospektive 1-Jahres-Follow-up-Untersuchung in der kombinierte multidimensionale Früherkennung und alters- und fachübergreifende integrierte Versorgung (Interventionsbedingung, n = 120) mit einer Standardbehandlung (historische Kontrollgruppe, n = 105) bei Jugendlichen und jungen Erwachsenen in der frühen Phase einer psychotischen Störung verglichen wird. Daten bei Aufnahme in die Studie weisen auf eine hohe Komplexität und Schwere der Erkrankung hin. Primäres Zielkriterium ist die Rate einer 6-monatigen kombiniert symptomatischen und funktionalen Remission zum Studienendpunkt.

Occurrence of Brachyspira hyodysenteriae in multiplier pig herds in Switzerland

OBJECTIVE: This research was aimed to determine the occurrence of Brachyspira (B.) hyodysenteriae in Swiss multiplier pig herds. MATERIALS AND METHODS: In a pilot study a direct real-time polymerase chain reaction (PCR) method for B. hyodysenteriae was compared to culture followed by PCR on 106 samples from three herds. Subsequently 40 multiplier herds were epidemiologically characterized and analysed for the presence of B. hyodysenteriae using direct PCR on 1412 rectal swabs. For external validation 20 swabs obtained from two positive conventional herds were analysed. RESULTS: The comparison of direct PCR with culture followed by PCR resulted in a moderate agreement (kappa index: 0.58). In the two conventional herds, 35% of the samples (7/20) tested positive. Samples from 39 multipliers tested negative. In one multiplier herd, 25% (9/36) of the samples tested PCR positive. Risk factors in the multiplier herd may have been rodents or birds, but not pig purchase. CONCLUSION AND CLINICAL RELEVANCE: B. hyodysenteriae have been detected in a Swiss multiplier herd, which underlines the threat of potential spread by replacement pigs. Consequently, a Brachyspira monitoring programme was established for Swiss multiplier herds.

Effects of medetomidine and its active enantiomer dexmedetomidine on N-demethylation of ketamine in canines determined in vitro using enantioselective capillary electrophoresis.

Cytochrome P450 (CYP) enzymes catalyze the metabolism of both, the analgesic and anesthetic drug ketamine and the α2 -adrenergic receptor-agonist medetomidine that is used for sedation and analgesia. As racemic medetomidine or its active enantiomer dexmedetomidine are often coadministered with racemic or S-ketamine in animals and dexmedetomidine together with S- or racemic ketamine in humans, drug-drug interactions are likely to occur and have to be characterized. Enantioselective CE with highly sulfated γ-cyclodextrin as chiral selector was employed for analyzing in vitro (i) the kinetics of the N-demethylation of ketamine mediated by canine CYP3A12 and (ii) interactions occurring with racemic medetomidine and dexmedetomidine during coincubation with ketamine and canine liver microsomes (CLM), canine CYP3A12, human liver microsomes (HLM), and human CYP3A4. For CYP3A12 without an inhibitor, Michaelis-Menten kinetics was determined for the single enantiomers of ketamine and substrate inhibition kinetics for racemic ketamine. Racemic medetomidine and dexmedetomidine showed an inhibition of the N-demethylation reaction in the studied canine enzyme systems. Racemic medetomidine is the stronger inhibitor for CLM, whereas there is no difference for CYP3A12. For CLM and CYP3A12, the inhibition of dexmedetomidine is stronger for the R- compared to the S-enantiomer of ketamine, a stereoselectivity that is not observed for CYP3A4. Induction is observed at a low dexmedetomidine concentration with CYP3A4 but not with CYP3A12, CLM, and HLM. Based on these results, S-ketamine combined with dexmedetomidine should be the best option for canines. The enantioselective CE assay with highly sulfated γ-cyclodextrin as chiral selector is an effective tool for determining kinetic and inhibition parameters of metabolic pathways.

Mus Hs 353 - Jubel-Cantate : zur Feÿer des 50jährigen Regierungsantritts Sr Maj: des Königs von Sachsen ; den 20: Sept. 1818 ; oder Erndte-Cantate ; op: 58

Musik von Carl Maria von Weber. Gedicht von Friedrich Kind. Nach Friedrich Kinds Jubel Cantate gedichtet von A. Wendt

Gegen die Einzelhaft oder das Zellengefängniß

von Friederike Kempner

Neues Puppenkochbuch

hrsg. von Tante Friederike