Dose- and substrate-dependent reduction of enteric methane and ammonia by natural additives in vitro

Ruminants contribute to global warming by emitting greenhouse gasses, particularly methane (CH4) which is a product of rumen fermentation. The use of feed additives able to modulate rumen fermentation is a promising strategy to reduce enteric CH4 and ammonia (NH3) emissions. Among the various strategies investigated, plant secondary metabolites (PSMs) have attracted attention due to their apparent potential to reduce enteric CH4 and NH3 emissions, and it would be possible to use such compounds as feed additives in organic production systems. In an in vitro system simulating rumen fermentation, we have tested the impact of different classes of naturally occurring PSMs; catechin and quercetin (flavonoids), salicylic acid (phenolic acid) and tannic acid (hydrolysable tannin). The PSMs were added to two different basal feeds (maize and grass silages) at three inclusion doses 1.5, 3 and 6% of the feed dry matter (DM). CH4 production was significantly lowered upon addition of quercetin to two basal feeds at doses of 3 and 6%, and this without changes in concentrations of total volatile fatty acid (VFA) produced during fermentation. Quercetin, as the only tested additive, reduced CH4 production, and when added to maize silage and grass silage, the reduction increased linearly with increasing dose, ie., by 51 and 43%, respectively, at a dose of 3% of feed DM and by 86 and 58%, respectively, at a dose of 6% of feed DM. Moreover, quercetin significantly reduced NH3 concentration by >12% at doses of 3 and 6% in feed DM irrespective of the basal feed used as compared to when the basal feeds were incubated alone. Although none of the other additives affected CH4 formation, several additives had significant impacts on concentrations of NH3 and VFAs in the incubated fluid after fermentation. This study demonstrated a dose-dependent ability of quercetin to reduce CH4 emission from rumen fermentation, however, the magnitude of the suppression of CH4 depended on the basal feed. Furthermore, quercetin reduced NH3 concentration irrespective of the basal feed type. These findings encourage to in vivo studies to verify whether quercetin can reduce CH4 emission also in cows

Obesity-Related Metabolome and Gut Microbiota Profiles of Juvenile Göttingen Minipigs—Long-Term Intake of Fructose and Resistant Starch

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Tuning and Tracking of Coherent Shear Waves in Molecular Films

We have determined the time-dependent displacement fields in molecular sub-micrometer thin films as response to femtosecond and picosecond laser pulse heating by time-resolved X-ray diffraction. This method allows a direct absolute determination of the molecular displacements induced by electron–phonon interactions, which are crucial for, for example, charge transport in organic electronic devices. We demonstrate that two different modes of coherent shear motion can be photoexcited in a thin film of organic molecules by careful tuning of the laser penetration depth relative to the thickness of the film. The measured response of the organic film to impulse heating is explained by a thermoelastic model and reveals the spatially resolved displacement in the film. Thereby, information about the profile of the energy deposition in the film as well as about the mechanical interaction with the substrate material is obtained

Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project

The dissociation of molecules, even the most simple hydrogen molecule, cannot be described accurately within density functional theory because none of the currently available functionals accounts for strong on-site correlation. This problem led to a discussion of properties that the local Kohn-Sham potential has to satisfy in order to correctly describe strongly correlated systems. We derive an analytic expression for the nontrivial form of the Kohn-Sham potential in between the two fragments for the dissociation of a single bond. We show that the numerical calculations for a one-dimensional two-electron model system indeed approach and reach this limit. It is shown that the functional form of the potential is universal, i.e., independent of the details of the two fragments.We acknowledge funding by the Spanish MEC (Grant No. FIS2007-65702-C02-01), “Grupos Consolidados UPV/EHU del Gobierno Vasco” (Grant No. IT-319-07), and the European Community through e-I3 ETSF project (Grant Agreement No. 211956).Peer reviewe

Dose- and substrate-dependent reduction of enteric methane and ammonia by natural additives in vitro

Ruminants contribute to global warming by emitting greenhouse gasses, particularly methane (CH4) which is a product of rumen fermentation. The use of feed additives able to modulate rumen fermentation is a promising strategy to reduce enteric CH4 and ammonia (NH3) emissions. Among the various strategies investigated, plant secondary metabolites (PSMs) have attracted attention due to their apparent potential to reduce enteric CH4 and NH3 emissions, and it would be possible to use such compounds as feed additives in organic production systems. In an in vitro system simulating rumen fermentation, we have tested the impact of different classes of naturally occurring PSMs; catechin and quercetin (flavonoids), salicylic acid (phenolic acid) and tannic acid (hydrolysable tannin). The PSMs were added to two different basal feeds (maize and grass silages) at three inclusion doses 1.5, 3 and 6% of the feed dry matter (DM). CH4 production was significantly lowered upon addition of quercetin to two basal feeds at doses of 3 and 6%, and this without changes in concentrations of total volatile fatty acid (VFA) produced during fermentation. Quercetin, as the only tested additive, reduced CH4 production, and when added to maize silage and grass silage, the reduction increased linearly with increasing dose, ie., by 51 and 43%, respectively, at a dose of 3% of feed DM and by 86 and 58%, respectively, at a dose of 6% of feed DM. Moreover, quercetin significantly reduced NH3 concentration by >12% at doses of 3 and 6% in feed DM irrespective of the basal feed used as compared to when the basal feeds were incubated alone. Although none of the other additives affected CH4 formation, several additives had significant impacts on concentrations of NH3 and VFAs in the incubated fluid after fermentation. This study demonstrated a dose-dependent ability of quercetin to reduce CH4 emission from rumen fermentation, however, the magnitude of the suppression of CH4 depended on the basal feed. Furthermore, quercetin reduced NH3 concentration irrespective of the basal feed type. These findings encourage to in vivo studies to verify whether quercetin can reduce CH4 emission also in cows

The Master/iSlave Dialectic: Post (Hegelian) Phenomenology and the Ethics of Technology

In part one of this paper I turn to Don Ihde to show how a technological object can occupy the role that “the other” plays for Hegel in his phenomenology as the structural features of Hegel's analyses of self-other relations can be found in Ihde's analyses of human-technology relations. I then turn to Singer's Wired for War and Gertz's Philosophy of War and Exile. Using these texts I show how the way soldiers treat robots by naming them, protecting them, and by even risking their lives to save them, illustrates Hegel's central claim: ethical life develops based on the process of discovering that to recognize others (whether human or technological) is to recognize ourselves and that to misrecognize others is to misrecognize ourselves. I conclude by offering suggestions as to how this understanding of ethical life as based on recognition and misrecognition can be applied to design ethics