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The effect of breed and diet on insulin response to glucose challenge and its relation to intra-muscular fat deposition was determined in 36 steers with 12 each of greater than 87% Wagyu (referred to as Wagyu), Wagyu x Limousin, and Limousin breeds. Weaned steers were blocked by weight into heavy, medium, and light calves and placed in six pens with two pens per weight type and with two steers of each breed per pen. Three pens with steers from each weight class were fed backgrounding and finishing diets for 259 d, while the other three pens were fed the same diets where 6% of the barley grain was replaced with sunflower oil. Prior to initiation of the finishing phase of the study the intravenous glucose tolerance test (IVGTT) was conducted in all steers. Once steers were judged as carrying adequate 12th-rib fat, based on weight and days on feed, they were harvested and graded and samples of the longissimus muscle were procured for determination of fat content and fatty acid composition. Dietary oil improved (P = 0.011; 0.06) ADG and feed conversion efficiency of steers during the latter part of backgrounding and only ADG during early part of the finishing period. Generally percent kidney, pelvic, and heart fat was the only adiposity assessment increased (P = 0.003) by dietary oil. The IYGTT results indicated that insulin response to intravenous glucose was lower in Limousin steers than in Wagyu steers. Dietary oil decreased (P = 0.052) fasting plasma insulin concentration in Wagyu steers compared with Limousin steers. The correlation coefficients among the IVGTT measures and intramuscular fat content or marbling score were less than 0.4, and only a negative trend existed between fasting insulin and USDA marbling scores. However, the carcasses of the Wagyu steers graded US Choice, and 66% of the Wagyu carcasses graded US Prime, which were substantially better than the quality grades obtained for the carcasses from the other breed types. Dietary oil did not affect muscle fat content but increased (P = 0.01) conjugated linoleic acid (CLA) concentrations by 339%. Results indicated that IVGTT measures were not appropriate indices of marbling potential in cattle and that dietary oil can enhance CLA content of beef. Key Words: Carcass Quality, Conjugated Linoleic Acid, Dietary Fat, Glucose, Insulin

Abstract: The production of hydrogen from ethanol steam reforming with Cu–Ni catalysts supported on MgO- and CaO-modified silica has been studied. Two promoting effects have been found: reduction of the metallic Cu–Ni particles size and strengthening of the metal–support interaction. Moreover, Mg- and Ca-promoted catalysts favour the formation of defective carbon, which is more reactive and thermodynamically easier to be removed during the ethanol steam reforming process. Consequently, higher hydrogen production and lower coke formation are achieved when Cu–Ni catalysts are supported on Mg- or Ca-modified silica in comparison to unmodified Cu–Ni/SiO2 catalyst. The highest hydrogen selectivity (84.8mol%) is reached with a Cu–Ni/Mg–SiO2 catalyst containing 10wt% Mg, while the incorporation of 10wt% Ca into Cu–Ni/SiO2 catalyst reduces considerably the amount of coke deposited from 58.4 to 26.3wt%, after 3h of time on stream. [Copyright &y& Elsevier]

The effect of breed and diet on insulin response to glucose challenge and its relation to intramuscular fat deposition was determined in 36 steers with 12 each of greater than 87% Wagyu (referred to as Wagyu), Wagyu × Limousin, and Limousin breeds. Weaned steers were blocked by weight into heavy, medium, and light calves and placed in six pens with two pens per weight type and with two steers of each breed per pen. Three pens with steers from each weight class were fed backgrounding and finishing diets for 259 d, while the other three pens were fed the same diets where 6% of the barley grain was replaced with sunflower oil. Prior to initiation of the finishing phase of the study the intravenous glucose tolerance test (IVGTT) was conducted in all steers. Once steers were judged as carrying adequate 12th-rib fat, based on weight and days on feed, they were harvested and graded and samples of the longissimus muscle were procured for determination of fat content and fatty acid composition. Dietary oil improved (P = 0.011; 0.06 ) ADG and feed conversion efficiency of steers during the latter part of backgrounding and only ADG during early part of the finishing period. Generally percent kidney, pelvic, and heart fat was the only adiposity assessment increased (P = 0.003) by dietary oil. The IVGTT results indicated that insulin response to intravenous glucose was lower in Limousin steers than in Wagyu steers. Dietary oil decreased (P = 0.052) fasting plasma insulin concentration in Wagyu steers compared with Limousin steers. The correlation coefficients among the IVGTT measures and intramuscular fat content or marbling score were less than 0.4, and only a negative trend existed between fasting insulin and USDA marbling scores. However, the carcasses of the Wagyu steers graded US Choice, and 66% of the Wagyu carcasses graded US Prime, which were substantially better than the quality grades obtained for the carcasses from the other breed types. Dietary oil did not... [ABSTRACT FROM AUTHOR]

Abstract: Ethanol steam reforming is an interesting alternative for hydrogen production since ethanol can be renewably obtained. Use of lamellar double hydroxides (LDHs) as precursors of nickel catalysts leads to highly dispersed metal particles in an aluminium structure. In this sense, a Ni(II)Al(III) catalyst was synthesized from a LDH precursor and tested in ethanol steam reforming. Although this catalyst presents high stability, acidity of alumina promotes carbon deposition from ethylene through ethanol dehydration. For this reason, in order to neutralize acid sites, a series of catalysts was prepared by Mg addition to LDH precursors varying Mg/Ni ratio. The effect of Mg/Ni ratio in the catalyst on coke formation during ethanol steam reforming was studied, resulting in significant reduction of the amount of deposited carbon for Mg/Ni ratio higher than 0.1. Moreover, Mg addition increases the catalytic activity due to lower ethylene formation, which competes with ethanol for the same Ni active sites. [Copyright &y& Elsevier]

Electroless Pore-Plated (ELP-PP) membranes were successfully incorporated for the first time into a membrane reactor to produce hydrogen by acetic acid steam reforming (AASR), exhibiting adequate resistance against harsh operating conditions. Membranes were prepared onto tubular PSS supports modified with Pd/CeO 2 particles and scaled-up around four times in length with high reproducibility respect previous studies. H 2 permeances from 4.49 to 5.67·10−4 mol m−2 s−1 Pa-0.5 were found for pure H 2 at 350–450 °C, decreasing for mixtures due to concentration-polarization at higher pressures but also certain inhibition caused by CO 2 at pressures below 50 Pa0.5. The combination of membranes with Ni/SBA-15 catalysts in packed-bed membrane reactors (PBMR) evidenced the simultaneous improvement of acetic acid conversion and hydrogen yield respect to analogous experiments in traditional packed-bed reactors (PBR). A very similar product distribution was obtained for both configurations, PBR and PBMR, when using fresh catalysts, although marked deviations were found in case of regenerating the catalysts. Then, higher selectivity towards coke reached for PBMR, which lead to around 30% for the most elevated pressure under investigation. However, even at these harsh conditions, the mechanical integrity of ELP-PP membranes was maintained. Thus, the benefits of combining catalysts and ELP-PP membranes in a PBMR for AASR were demonstrated. • Successful scale-up of an ELP-PP membrane with Pd/CeO 2 barrier to 110 mm in length. • Pd thickness around 15 μm with no marked differences along the axial direction. • H 2 permeances from 4.49 to 5.67·10−4 mol·m−2·s−1·Pa-0.5 for pure H 2 at 350–450 °C. • Noticeably inhibition caused by CO 2 was found in permeation tests with mixtures. • Mechanical integrity of ELP-PP membrane in PBMR and improvement of H 2 production. [ABSTRACT FROM AUTHOR]