Verdaulichkeit und Abbaubarkeit von Ganzpflanzensilagen aus Getreide und Erbsen

Mischungen aus unreifen Protein- und Getreideganzpflanzen benötigen nur wenig Arbeits- und Pflegeaufwand und können bei Futtermangel für einen Vorrat sorgen. Um bei der Nährwertschätzung das Additivitätsprinzip zu prüfen, wurden in vivo Verdaulichkeitsversuche und in sacco Abbaubarkeitsversuche mit Silagen zweier verschiedener Mischungen mit unterschiedlich hohen Anteilen an Proteinpflanzen durchgeführt. Die Mischung mit tiefem Erbsengehalt, ERBS-t war folgendermassen zusammengesetzt: 60 % Triticale, 28 % Hafer und 13 % Erbsen. Die Mischung mit einem hohen Erbsenanteil, ERBS-h enthielt 35 % Triticale, 24 % Hafer und 41 % Erbsen. Dieselben Versuche wurden ebenfalls mit den drei Komponenten der Mischungen (Triticale, Hafer und Futtererbsen) durchgeführt. Von den beiden Mischungen erzielte ERBS-h die höchsten Verdaulichkeiten (für organische Substanz 76,5 vs. 61,9 %). Hinsichtlich der ruminalen Rohproteinabbaubarkeit unterschieden sich die beiden Mischungen nicht. Die errechneten Nährwerte lagen für ERBS-h bei 6,4 MJ Nettoenergie Laktation (NEL) pro kg Trockensubstanz (TS) und für ERBS-t lediglich bei 4,9 MJ NEL / kg TS. Die in der Futterkrippe aus Reinsilagen rekonstituierten Mischungen erzielten ähnliche Werte wie die ausgesäten Mischungen. Die Additivitätshypothese, bei welcher für die Schätzung der Nährwerte der Mischungen die Einzelkomponenten additiv zusammengerechnet werden, erwies sich für die getreidedominierte Mischung ERBS-t als gut, wohingegen die Werte für ERBS-h stark unterschätzt wurden

In situ electrochemical cells to study the oxygen evolution reaction by near ambient pressure x-ray photoelectron spectroscopy

In this contribution, we report the development of in situ electrochemical cells based on proton exchange membranes suitable for studying interfacial structural dynamics of energy materials under operation by near ambient pressure X-ray photoelectron spectroscopy. We will present both the first design of a batch-type two-electrode cell prototype and the improvements attained with a continuous flow three-electrode cell. Examples of both sputtered metal films and carbon-supported metal nanostructures are included demonstrating the high flexibility of the cells to study energy materials. Our immediate focus was on the study of the oxygen evolution reaction, however, the methods described herein can be broadly applied to reactions relevant in energy conversion and storage devices

Are Au nanoparticles on oxygen free supports catalytically active?

Gold nanoparticles Au NPs on oxygen free supports were examined using near ambient pressure X ray photoelectron spectroscopy NAP XPS under CO oxidation conditions, and ex situ using scanning electron microscopy SEM and transmission electron microscopy TEM . Our observations demonstrate that Au NPs supported on carbon materials are inactive, regardless of the preparation method. Ozone O3 treatment of carbon supports leads oxygen functionalization of the supports. When subsequently exposed to a CO feed, CO is oxidized by the functionalized sites of the carbon support via a stoichiometric pathway. Microscopy reveals that the reaction with CO does not change the morphology of the Au NPs. In situ XPS reveals that the O3 treatment gives rise to additional Au 4f and O 1s peaks at binding energies of 85.25 85.6 eV and 529.4 530 eV, respectively, which are assigned to the presence of Au oxide. A surface oxide phase is formed during the activation of Au NPs supported on Au foil by O3 treatment. However, this phase decomposes in vacuum and the remaining low coordinative atoms do not have sufficient catalytic properties to oxidize CO, so the size reduction of Au NPs and or oxidation of Au NPs is not sufficient to activate A

Operando spectroscopy study of the carbon dioxide electro-reduction by iron species on nitrogen-doped carbon

The carbon–carbon coupling via electrochemical reduction of carbon dioxide represents the biggest challenge for using this route as platform for chemicals synthesis. Here we show that nanostructured iron (III) oxyhydroxide on nitrogen-doped carbon enables high Faraday efficiency (97.4%) and selectivity to acetic acid (61%) at very-low potential (−0.5 V vs silver/silver chloride). Using a combination of electron microscopy, operando X-ray spectroscopy techniques and density functional theory simulations, we correlate the activity to acetic acid at this potential to the formation of nitrogen-coordinated iron (II) sites as single atoms or polyatomic species at the interface between iron oxyhydroxide and the nitrogen-doped carbon. The evolution of hydrogen is correlated to the formation of metallic iron and observed as dominant reaction path over iron oxyhydroxide on oxygen-doped carbon in the overall range of negative potential investigated, whereas over iron oxyhydroxide on nitrogen-doped carbon it becomes important only at more negative potentials

New variable separation approach: application to nonlinear diffusion equations

The concept of the derivative-dependent functional separable solution, as a generalization to the functional separable solution, is proposed. As an application, it is used to discuss the generalized nonlinear diffusion equations based on the generalized conditional symmetry approach. As a consequence, a complete list of canonical forms for such equations which admit the derivative-dependent functional separable solutions is obtained and some exact solutions to the resulting equations are described.Comment: 19 pages, 2 fig

The role of the copper oxidation state in the electrocatalytic reduction of CO2 into valuable hydrocarbons

Redox-active copper catalysts with accurately prepared oxidation states (Cu0, Cu+ and Cu2+) and high selectivity to C2 hydrocarbon formation, from electrocatalytic cathodic reduction of CO2, were fabricated and characterized. The electrochemically prepared copper-redox electro-cathodes yield higher activity for the production of hydrocarbons at lower oxidation state. By combining advanced X-ray spectroscopy and in situ micro-reactors it was possible to unambiguously reveal the variation in the complex electronic structure that the catalysts undergo at different stages (i.e. during fabrication and electrocatalytic reactions). It was found that the surface, sub-surface and bulk properties of the electrochemically prepared catalysts are dominated by the formation of copper carbonates on the surface of cupric-like oxides, which prompts catalyst deactivation by restraining effective charge transport. Furthermore, the formation of reduced or partially-reduced copper catalysts yields the key dissociative proton-consuming reactive adsorption of CO2 to produce CO, allowing the subsequent hydrogenation into C2 and C1 products by dimerization and protonation. These results yield valuable information on the variations in the electronic structure that redox-active copper catalysts undergo in the course of the electrochemical reaction, which, under extreme conditions are mediated by thermodynamics but, critically, kinetics dominate near the oxide/metal phase transitions

Possible Fruit Protein Effects on Primate Communities in Madagascar and the Neotropics

The ecological factors contributing to the evolution of tropical vertebrate communities are still poorly understood. Primate communities of the tropical Americas have fewer folivorous but more frugivorous genera than tropical regions of the Old World and especially many more frugivorous genera than Madagascar. Reasons for this phenomenon are largely unexplored. We developed the hypothesis that Neotropical fruits have higher protein concentrations than fruits from Madagascar and that the higher representation of frugivorous genera in the Neotropics is linked to high protein concentrations in fruits. Low fruit protein concentrations in Madagascar would restrict the evolution of frugivores in Malagasy communities.We reviewed the literature for nitrogen concentrations in fruits from the Neotropics and from Madagascar, and analyzed fruits from an additional six sites in the Neotropics and six sites in Madagascar. Fruits from the Neotropical sites contain significantly more nitrogen than fruits from the Madagascar sites. Nitrogen concentrations in New World fruits are above the concentrations to satisfy nitrogen requirements of primates, while they are at the lower end or below the concentrations to cover primate protein needs in Madagascar.Fruits at most sites in the Neotropics contain enough protein to satisfy the protein needs of primates. Thus, selection pressure to develop new adaptations for foods that are difficult to digest (such as leaves) may have been lower in the Neotropics than in Madagascar. The low nitrogen concentrations in fruits from Madagascar may contribute to the almost complete absence of frugivorous primate species on this island

Knock Down of Heat Shock Protein 27 (HspB1) Induces Degradation of Several Putative Client Proteins

Hsp27 belongs to the heat shock protein family and displays chaperone properties in stress conditions by holding unfolded polypeptides, hence avoiding their inclination to aggregate. Hsp27 is often referenced as an anti-cancer therapeutic target, but apart from its well-described ability to interfere with different stresses and apoptotic processes, its role in non-stressed conditions is still not well defined. In the present study we report that three polypeptides (histone deacetylase HDAC6, transcription factor STAT2 and procaspase-3) were degraded in human cancerous cells displaying genetically decreased levels of Hsp27. In addition, these proteins interacted with Hsp27 complexes of different native size. Altogether, these findings suggest that HDAC6, STAT2 and procaspase-3 are client proteins of Hsp27. Hence, in non stressed cancerous cells, the structural organization of Hsp27 appears to be a key parameter in the regulation by this chaperone of the level of specific polypeptides through client-chaperone type of interactions