Reduction of toxic effects of aflatoxin B1 by using baker yeast (Saccharomyces cerevisiae) in growing broiler chicks diets

This study was carried out to investigate the effects of adding baker yeast (BY), chlortetracycline (CTC) and both BY + CTC to a control diet containing 200 ng/g of aflatoxin B1 (C + AFB1) on performance, serum parameters and pathologyc alterations of broilers. A total 100 chicks (Ross PM 3) were divided into five groups in individual cages and each containing 20 animals. BY, a rich source of protein and vitamin B complex, was mixed into the diets at 2.0 %, CTC was mixed into the diet at 2.5 ng/g. Feed consumption, body weight and feed efficiency were recorded weekly. Serum parameters and pathologyc alterations were determined at the end of the study. Dead animals were recorded daily. Liver changes were clearly apparent in the C+AFB1and C+ AFB1+CTC most of the livers were enlarged, yellow and had pethecial hemorrhages. Canalicula cholestosis was absent in group C+AFB1 and C+ AFB1+CTC, but not others. When compared to the control (C) group, alkaline phosphatase (ALP), appear to be significantly increased in the C+AFB1 and C+CTC+ AFB1 groups. Serum glutamic oxalacetic transaminase (GOT)was increased in C+AFB1 birds. Serum alphaphetoprotein was not affected by the treatments. Feed consumption and body weight were significantly reduced in group AFB1. Birds receiving BY + AFB1, CTC + AFB1 and BY + CTC + AFB1 had a significantly higher body weight than group C+AFB1. Feed efficiency was better in group CTC + AFB1 than the others. The findings of this research suggest tha BY (2%) can partly counteract some of the toxic effects of AFB1

Experimental design and statistical modeling methodology for wind tunnel aerodynamics of an agile missile to improve the simulation accuracy and performance

© 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Wind tunnel testing is an essential procedure to investigate the aerodynamics forces and moments. In this paper, a methodology is presented to perform such test in an efficient way. Experimental design process is carried out before the testing in order to cover the flight regime as much as possible with the least possible number of tests. After the determination of the test matrix and conducting the wind-on tests, the modeling of the data is the next step. On that matter, two nonlinear modeling techniques are presented and compared with each other. First technique is the well-known Artificial Neural Networks (ANN) and the second one is relatively lesser known but a powerful modeling algorithm Multivariate Adaptive Regression Splines (MARS). After the data is modeled using both approaches, their statistical metrics are compared and the models are integrated into a high fidelity 6DoF equations of motion model. Since all this effort is to improve the simulation accuracy and performance, 6DoF simulations are performed using three different flight scenarios that cover the flight regime of the missile. Afterwards, obtained trajectory and flight parameters are compared. Finally, various flight conditions are produced and the models are evaluated in batch mode to see their performances in terms of computational speed