288 research outputs found
Effect of pH and level of concentrate in the diet on the production of biohydrogenation intermediates in a dual-flow continuous culture
Milk fat depression in cows fed high-grain diets has been related to an increase in the concentration of trans-10 C-18:1 and trans-10, cis-12 conjugated linoleic acid (CLA) in milk. These fatty acids (FA) are produced as a result of the alteration in rumen biohydrogenation of dietary unsaturated FA. Because a reduction in ruminal pH is usually observed when high-concentrate diets are fed, the main cause that determines the alteration in the biohydrogenation pathways is not clear. The effect of pH (6.4 vs. 5.6) and dietary forage to concentrate ratios (F:C; 70:30 F:C vs. 30:70 F:C) on rumen microbial fermentation, effluent FA profile, and DNA concentration of bacteria involved in lipolysis and biohydrogenation processes were investigated in a continuous culture trial. The dual-flow continuous culture consisted of 2 periods of 8 d (5 d for adaptation and 3 d for sampling), with a 2 x 2 factorial arrangement of treatments. Samples from solid and liquid mixed effluents were taken for determination of total N, ammonia-N, and volatile fatty acid concentrations, and the remainder of the sample was lyophilized. Dry samples were analyzed for dry matter, ash, neutral and acid detergent fiber, FA, and purine contents. The pH 5.6 reduced organic matter and fiber digestibility, ammonia-N concentration and flow, and crude protein degradation, and increased nonammonia and dietary N flows. The pH 5.6 decreased the flow of C-18:0, trans-11 C-18:1 and cis-9, trans-11 CLA, and increased the flow of trans-10 C-18:1, C18:2n-6, C18:3n-3, trans-11, cis-15 C-18:2 and trans-10, cis-12 CLA in the 1 h after feeding effluent. The pH 5.6 reduced Anaerovibrio lipolytica (32.7 vs. 72.1 pg/10 ng of total DNA) and Butyrivibrio fibrisolvens vaccenic acid subgroup (588 vs. 1,394 pg/10 ng of total DNA) DNA concentrations. The high-concentrate diet increased organic matter and fiber digestibility, nonammonia and bacterial N flows, and reduced ammonia-N concentration and flow. The high-concentrate diet reduced trans-11 C-18:1 and trans-10 C-18:1, and increased C18:2n-6, C18:3n-3 and trans-10, cis-12 CLA proportions in the 1 h after feeding effluent. The increase observed in trans-10, cis-12 CLA proportion in the 1 h after feeding effluent due to the high-concentrate diet was smaller that that observed at pH 5.6. Results indicate that the pH is the main cause of the accumulation of trans-10 C-18:1 and trans-10, cis-12 CLA in the effluent, but the trans-10, cis-12 CLA proportion can be also affected by high levels of concentrate in the diet
Adaptation Framework and Strategy Part 3: an adaptation strategy for agriculture in Ningxia, Northwest China
Phase-Covariant Quantum Benchmarks
We give a quantum benchmark for teleportation and quantum storage experiments
suited for pure and mixed test states. The benchmark is based on the average
fidelity over a family of phase-covariant states and certifies that an
experiment can not be emulated by a classical setup, i.e., by a
measure-and-prepare scheme. We give an analytical solution for qubits, which
shows important differences with standard state estimation approach, and
compute the value of the benchmark for coherent and squeezed states, both pure
and mixed.Comment: 4 pages, 2 figure
Adaptation Framework and Strategy Part 2: application of the adaptation framework - a case study of Ningxia, Northwest China
Desarrollo de un simulador de explotaciones lecheras para valorar el efecto de diferentes estrategias productivas sobre el rendimiento técnico y económico
publishedTomo I . Sección: Sistemas Ganaderos-Economía y Gestión. Sesión: Producción de leche. Ponencia nº 2
The Impacts of Climate Change on Chinese Agriculture - Phase II National Level Study final report
High-fidelity entanglement swapping with fully independent sources
Entanglement swapping allows to establish entanglement between independent
particles that never interacted nor share any common past. This feature makes
it an integral constituent of quantum repeaters. Here, we demonstrate
entanglement swapping with time-synchronized independent sources with a
fidelity high enough to violate a Clauser-Horne-Shimony-Holt inequality by more
than four standard deviations. The fact that both entangled pairs are created
by fully independent, only electronically connected sources ensures that this
technique is suitable for future long-distance quantum communication
experiments as well as for novel tests on the foundations of quantum physics.Comment: added technical details and extended introduction and conclusion,
slightly modified the abstract, corrected a mistake in the affiliation
Future cereal production in China: Modelling the interaction of climate change, water availability and socio-economic scenarios. The Impacts of Climate Change on Chinese Agriculture – Phase II Final Report
Conditional beam splitting attack on quantum key distribution
We present a novel attack on quantum key distribution based on the idea of
adaptive absorption [calsam01]. The conditional beam splitting attack is shown
to be much more efficient than the conventional beam spitting attack, achieving
a performance similar to the, powerful but currently unfeasible, photon number
splitting attack. The implementation of the conditional beam splitting attack,
based solely on linear optical elements, is well within reach of current
technology.Comment: Submitted to Phys. Rev.
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