Effects of grain type on growth and performance of steers limit-fed grain-based diets

Five hundred fifty two steers were used in a growth experiment designed to evaluate the use of grain sorghum in a limit-feeding program. Dry-rolled corn, dry-rolled grain sorghum, steam-flaked grain sorghum, or combinations of grains totaled 70% (dry matter basis) of the diet. Daily intakes were restricted to 2% of body weight (dry matter basis). Cattle were fed their assigned diet for 95 days followed by a 5- day period on a common diet to compensate for differences in gut fill. Steam-flaked grain sorghum and dry-rolled corn yielded similar gain efficiencies and average daily gains. Dry-rolled grain sorghum, however, had 71% the value of dry-rolled corn and 72% the value of steamflaked grain sorghum. These values became 80% and 83% when the 5 days on a common diet were considered. No significant associative effects were observed for the combinations of grains. The data clearly indicate that grains that are slowly fermented (i.e. dry-rolled grain sorghum) are less desirable in a limit-feeding program. Differences among grains observed in full-fed, finishing diets will likely be as great or greater with high-grain, limit-fed diets. Consequently, extensive processing of grain sorghum would be as beneficial in a limit-fed ration for growing cattle as it is perceived to be in a fullfed, finishing diet

Performance of growing heifers fed prairie hay and supplemented with alfalfa and(or) cooked molasses blocks of different protein concentrations

Crossbred heifers (683 lb; n = 175; 30 pens) were used to evaluate alfalfa and cooked molasses block supplementation to prairie hay. Treatments were arranged in a 2×3 factorial with the factors being 0 or 5 lbs of alfalfa supplementation, and supplementation with no block or with low or high protein blocks (analyzed to contain 14.4 and 27.5% crude protein, respectively). Heifers had ad libitum access to prairie hay and salt. The experiment was 89 days, with heifers fed blocks for 84 days. During days 5 to 19, heifers had ad libitum access to blocks. Thereafter, access was restricted to 4 hours daily. No significant interactions occurred between alfalfa and blocks for intake or gain. Supplementation with alfalfa increased total forage intake by 49% (18.4 vs. 12.3 lb/day), and gains from –.39 lb/day to +.95 lb/day. Intake of the blocks was lower when alfalfa was supplemented (.76 vs. .98 lb/day). Heifers fed the high-protein block gained more weight (.46 lb/day) than those fed the lowprotein block (.25 lb/day) or no block (.12 lb/day). Heifers fed the high-protein block ate more forage (16.1 lb/day) than those fed the low-protein block (14.8 lb/day), with heifers fed no block (15.3 lb/day) being intermediate. Intake of block was greater for the high-protein (.93 lb/day) than for the low-protein block (.81 lb/day). Differences in forage intake accounted for much of the differences in performance among treatments

A coherent kinetic model of sensing and response in halobacterium salinarium phototaxis based on the mechanism of flagellar motor switching

Halobacterium salinarium shows a qualitatively different swimming behavior than E. coli, what demands a different mechanism of flagellar motor switching. In this study we postulate general properties of the switching mechanism in Halobacteria, derived from experimental findings and present a detailed model that quantitatively reproduces various different experimental results with the same set of parameters. Even seemingly paradox findings are accomplished by the presented model

Modular modeling of cellular systems with ProMoT/Diva

Motivation: Need for software to setup and analyze complex mathematical models for cellular systems in a modular way, that also integrates the experimental environment of the cells. Results: A computer framework is described which allows the building of modularly structured models using an abstract, modular and general modeling methodology. With this methodology, reusable modeling entities are introduced which lead to the development of a modeling library within the modeling tool ProMot. The simulation environment Diva is used for numerical analysis and parameter identification of the models. The simulation environment provides a number of tools and algorithms to simulate and analyze complex biochemical networks. The described tools are the first steps towards an integrated computer-based modeling, simulation and visualization environment. © Oxford University Press 2003 [accessed 2014 February 13th

Wave front sensor for highly accurate characterization of flatness on wafer surfaces

Semiconductor manufacturing processes start on bare silicon substrates having excellent surface flatness. In the subsequent process chain of manufacturing of integrated circuits, it is crucial to maintain this initial surface flatness. New lithography technologies, as for example immersion lithography and Extreme Ultra Violet (EUV), require high flatness of the exposure surfaces as e.g. the depth of focus is impacted. Integrated device manufacturers use different technologies involving materials such as metals, semiconductors, and isolators to build three-dimensional structures on the wafer. The miscellaneousness of materials on the surface of wafers with highly integrated circuits limits the use of metrology developed for flatness analysis of bare silicon wafers. Nevertheless, it is essential for semiconductor manufacturing to measure and control the topography of wafer surfaces at nanometer scale. Wave front sensing was developed to characterize topography on bare and patterned wafer surfaces. Post processing of the acquired data applied 2 D Gaussian high pass filters to obtain the flatness data. The standard deviation of the flatness data after filtering was almost independent with respect to the lateral resolution. On bare wafer surfaces, the standard deviation was found to be below 1 nm, on patterned surfaces to be below 10 nm. Both, changes in reflectivity and filtering were found to impact and limit the accuracy of the determination of flatness. The accuracy of flatness measurement was found to be better than 20 nm. The results were validated by using a wavefront sensor according to the method of Makyoh. The technique has a high potential to provide high speed, contactless, and local inspection of flatness on bare and patterned wafer surfaces

Modular modeling of cellular systems with ProMoT/Diva

Motivation: Need for software to setup and analyze complex mathematical models for cellular systems in a modular way, that also integrates the experimental environment of the cells. Results: A computer framework is described which allows the building of modularly structured models using an abstract, modular and general modeling methodology. With this methodology, reusable modeling entities are introduced which lead to the development of a modeling library within the modeling tool ProMot. The simulation environment Diva is used for numerical analysis and parameter identification of the models. The simulation environment provides a number of tools and algorithms to simulate and analyze complex biochemical networks. The described tools are the first steps towards an integrated computer-based modeling, simulation and visualization environment