An Analytical Assessment of NASA's N+1 Subsonic Fixed Wing Project Noise Goal

The Subsonic Fixed Wing Project of NASA's Fundamental Aeronautics Program has adopted a noise reduction goal for new, subsonic, single-aisle, civil aircraft expected to replace current 737 and A320 airplanes. These so-called 'N+1' aircraft - designated in NASA vernacular as such since they will follow the current, in-service, 'N' airplanes - are hoped to achieve certification noise goal levels of 32 cumulative EPNdB under current Stage 4 noise regulations. A notional, N+1, single-aisle, twinjet transport with ultrahigh bypass ratio turbofan engines is analyzed in this study using NASA software and methods. Several advanced noise-reduction technologies are analytically applied to the propulsion system and airframe. Certification noise levels are predicted and compared with the NASA goal

Meta-analysis of genome-wide association studies for cattle stature identifies common genes that regulate body size in mammals

Stature is affected by many polymorphisms of small effect in humans1. In contrast, variation in dogs, even within breeds, has been suggested to be largely due to variants in a small number of genes2,3. Here we use data from cattle to compare the genetic architecture of stature to those in humans and dogs. We conducted a meta-analysis for stature using 58,265 cattle from 17 populations with 25.4 million imputed whole-genome sequence variants. Results showed that the genetic architecture of stature in cattle is similar to that in humans, as the lead variants in 163 significantly associated genomic regions (P < 5 7 10 128) explained at most 13.8% of the phenotypic variance. Most of these variants were noncoding, including variants that were also expression quantitative trait loci (eQTLs) and in ChIP\u2013seq peaks. There was significant overlap in loci for stature with humans and dogs, suggesting that a set of common genes regulates body size in mammals

BIOPROCESS DEVELOPMENT FOR SERINE ALKALINE PROTEASE PRODUCTION: A REVIEW

This work is the result of the convergence of the research in biochemical reaction engineering and metabolic flux analysis for serine alkaline protease (SAP) production. The genus Bacillus includes a variety of industrially important species that are known to secrete a large number of extracellular proteases and are used among many species as producer of SAP enzyme. Therefore, in the first part of the present article an overview to serine alkaline protease and regulation of its synthesis and secretion in Bacillus is presented. In the second part, a detailed review of the published information on the bioprocess medium design and bioreactor operation parameters are discussed in relation to the concentrations of the byproducts, i.e. neutral protease, amylase, amino acids, organic acids and alcohols. In the third part, papers on metabolic flux analysis for SAP are reviewed with the emphasis on SAP overproduction potential of the Bacillus licheniformis, the effect of oxygen transfer on the bioreaction-network fluxes and the need for oxygen transfer strategies. The metabolic bottlenecks and strategies for increasing the yield and selectivity of SAP fermentation process are discussed