Uncertainty in techno-economic estimates of cellulosic ethanol production due to experimental measurement uncertainty.

Background: Cost-effective production of lignocellulosic biofuels remains a major financial and technical challenge at the industrial scale. A critical tool in biofuels process development is the techno-economic (TE) model, which calculates biofuel production costs using a process model and an economic model. The process model solves mass and energy balances for each unit, and the economic model estimates capital and operating costs from the process model based on economic assumptions.

Ovarian activity and reproductive performance of dairy cows fed different amounts of phosphorus.

Fifty-four multiparous Holsteins were utilized to determine the effect of dietary P on ovarian activity and reproductive performance. Cows were assigned at calving to diets containing 0.35 or 0.

Ovarian follicular activity in lactating Holstein cows supplemented with monensin.

The objective of this study was to determine effects of monensin on ovarian follicular development and reproductive performance in postpartum dairy cows. Forty-eight multiparous Holstein cows were randomly assigned to receive either a control total mixed ration (n = 24) or the same diet plus 22 mg of monensin/kg (n = 24) from 21 d before anticipated calving until cows were either confirmed pregnant or were >180 d postpartum. Monensin had no effect on development of the first dominant follicle postpartum or the numbers of class 1 (3 to 5 mm), 2 (6 to 9 mm), or 3 (10 to 15 mm) follicles.

Utilization of phosphorus in lactating cows fed varying amounts of phosphorus and forage.

The objective of this study was to determine the effect of dietary forage proportion and P content on fecal P excretion. Four dietary treatments were formed in a 2 x 2 factorial arrangement. The P content was 0.

Expression of luteinizing hormone genes in bovine conceptuses.

RT-PCR analysis demonstrated that bovine conceptuses at days 16, 23 and 30 expressed LH-beta-like and glycoprotein hormone alpha-like transcript sequences; adult kidney, liver and brain produced predominantly unspliced products. Sequencing of the LH-beta-like fragment (from conceptuses at day 30) indicated complete homology with the published sequence. In addition, ribonuclease protection assay of RNA samples from bovine conceptuses at day 30 with a bovine LH-beta probe revealed the presence of protected molecules that appeared to be full length.