The Impact of Economic Factors and Acquisition Reforms on the Cost of Defense Weapon Systems

Cost overruns in weapon system purchases have plagued the Department of Defense (DoD) throughout its history and have resulted in schedule delays and potentially reduced combat capability. This thesis created an empirical model that begins to explain those cost overruns. The model describes how changes in defense budgets, consolidation of the defense industry, acquisition reform, war, and cost estimating error are related to cost overruns. The cost performance of 186 major weapon system programs managed by the Air Force, Army, and Navy from 1970 to 2002 was described using a panel regression model. This research found that funding instability resulting from changing levels of defense budgets accounted for an increase of over $13.3 billion in weapon system costs since 1970. This research also found that the defense industry consolidation of the 1990s did not result in significant savings to the DoD. Finally, this research found that contrary to past studies, several acquisition reforms are correlated with a decrease in weapon system cost overruns. In particular, reforms resulting from the Nunn-McCurdy Act of 1982, the Packard Commission Recommendations of 1986 and the Federal Acquisition Streamlining Act (FASA) of 1994 resulted in savings of almost$124 billion since 1982

Synthetic metabolons for metabolic engineering.

Journal ArticleResearch Support, Non-U.S. Gov'tReviewThis is a pre-copyedited, author-produced PDF of an article accepted for publication in Journal of Experimental Botany following peer review. The definitive publisher-authenticated version J. Exp. Bot. (2014) 65 (8) pp. 1947-1954 is available online at: http://jxb.oxfordjournals.org/content/65/8/1947It has been proposed that enzymes can associate into complexes (metabolons) that increase the efficiency of metabolic pathways by channelling substrates between enzymes. Metabolons may increase flux by increasing the local concentration of intermediates, decreasing the concentration of enzymes needed to maintain a given flux, directing the products of a pathway to a specific subcellular location or minimizing the escape of reactive intermediates. Metabolons can be formed by relatively loose non-covalent protein-protein interaction, anchorage to membranes, and (in bacteria) by encapsulation of enzymes in protein-coated microcompartments. Evidence that non-coated metabolons are effective at channelling substrates is scarce and difficult to obtain. In plants there is strong evidence that small proportions of glycolytic enzymes are associated with the outside of mitochondria and are effective in substrate channelling. More recently, synthetic metabolons, in which enzymes are scaffolded to synthetic proteins or nucleic acids, have been expressed in microorganisms and these provide evidence that scaffolded enzymes are more effective than free enzymes for metabolic engineering. This provides experimental evidence that metabolons may have a general advantage and opens the way to improving the outcome of metabolic engineering in plants by including synthetic metabolons in the toolbox

Use of Geotechnical Design Summary Report as a Management Tool for Resolving Disputes on Underground Construction Projects

The Los Angeles Metro Rail Subway project is initially planned for 30 km (18 mi) of twin, 6-m (20-ft) diameter bored tunnels under city streets and a total of 16 stations. This paper describes briefly the history of the project, the geologic setting, and the challenges encountered during design or anticipated during construction. It also introduces, as part of contract documentation, an interpretive geotechnical baseline report which establishes the basis for identification and recognition of site condition baselines . In so doing, this report (known as a GDSR ) has proven to be an effective tool for ameliorating contractual problems and facilitating conflict resolution

Characterizing Multi-Scale Self-Similar Behavior and Non-Statistical Properties of Financial Time Series

We make use of wavelet transform to study the multi-scale, self similar behavior and deviations thereof, in the stock prices of large companies, belonging to different economic sectors. The stock market returns exhibit multi-fractal characteristics, with some of the companies showing deviations at small and large scales. The fact that, the wavelets belonging to the Daubechies' (Db) basis enables one to isolate local polynomial trends of different degrees, plays the key role in isolating fluctuations at different scales. One of the primary motivations of this work is to study the emergence of the $k^{-3}$ behavior \cite{hes5} of the fluctuations starting with high frequency fluctuations. We make use of Db4 and Db6 basis sets to respectively isolate local linear and quadratic trends at different scales in order to study the statistical characteristics of these financial time series. The fluctuations reveal fat tail non-Gaussian behavior, unstable periodic modulations, at finer scales, from which the characteristic $k^{-3}$ power law behavior emerges at sufficiently large scales. We further identify stable periodic behavior through the continuous Morlet wavelet.Comment: 11 pages, 8 figures, bibliography updated, conclusion added, minor changes in the manuscrip

Intraspecfic variation in cold-temperature metabolic phenotypes of Arabidopsis lyrata ssp petraea

Atmospheric temperature is a key factor in determining the distribution of a plant species. Alongside this, plant populations growing at the margin of their range may exhibit traits that indicate genetic differentiation and adaptation to their local abiotic environment. We investigated whether geographically separated marginal populations of Arabidopsis lyrata ssp. petraea have distinct metabolic phenotypes associated with exposure to cold temperatures. Seeds of A. petraea were obtained from populations along a latitudinal gradient, namely Wales, Sweden and Iceland and grown in a controlled cabinet environment. Mannose, glucose, fructose, sucrose and raffinose concentrations were different between cold treatments and populations, especially in the Welsh population, but polyhydric alcohol concentrations were not. The free amino acid compositions were population specific, with fold differences in most amino acids, especially in the Icelandic populations, with gross changes in amino acids, particularly those associated with glutamine metabolism. Metabolic fingerprints and profiles were obtained. Principal component analysis (PCA) of metabolite fingerprints revealed metabolic characteristic phenotypes for each population and temperature. It is suggested that amino acids and carbohydrates were responsible for discriminating populations within the PCA. Metabolite fingerprinting and profiling has proved to be sufficiently sensitive to identify metabolic differences between plant populations at different atmospheric temperatures. These findings show that there is significant natural variation in cold metabolism among populations of A. l. petraea which may signify plant adaptation to local climates

Identification of novel seed longevity genes related to oxidative stress and seed coat by genome wide association studies and reverse genetics

[EN] Seed longevity is a polygenic trait of relevance for agriculture and for understanding the effect of environment on the ageing of biological systems. In order to identify novel longevity genes, we have phenotyped the natural variation of 270 ecotypes of the model plant,Arabidopsis thaliana, for natural ageing and for three accelerated ageing methods. Genome-wide analysis, using publicly available single-nucleotide polymorphisms (SNPs) data sets, identified multiple genomic regions associated with variation in seed longevity. Reverse genetics of 20 candidate genes in Columbia ecotype resulted in seven genes positive for seed longevity (PSAD1,SSLEA,SSTPR,DHAR1,CYP86A8,MYB47andSPCH) and five negative ones (RBOHD,RBOHE,RBOHF,KNAT7andSEP3). In this uniform genetic background, natural and accelerated ageing methods provided similar results for seed-longevity in knock-out mutants. The NADPH oxidases (RBOHs), the dehydroascorbate reductase (DHAR1) and the photosystem I subunit (PSAD1) highlight the important role of oxidative stress on seed ageing. The cytochrome P-450 hydroxylase, CYP86A8, and the transcription factors, MYB47, KNAT7 and SEP3, support the protecting role of the seed coat during seed ageing.Ministerio de Ciencia, Innovacion y Universidades, Grant/Award Number: BIO2017-88898-PRenard, J.; Niñoles Rodenes, R.; Martínez-Almonacid, I.; Gayubas, B.; Mateos-Fernández, R.; Bissoli, G.; Bueso Rodenas, E.... (2020). Identification of novel seed longevity genes related to oxidative stress and seed coat by genome wide association studies and reverse genetics. Plant Cell & Environment. 43(10):2523-2539. https://doi.org/10.1111/pce.13822S25232539431

Deficiency of GDP-l-galactose phosphorylase, an enzyme required for ascorbic acid synthesis, reduces tomato fruit yield

This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this recordReduced GDP-L-galactose phosphorylase expression and deficiency of ascorbic acid content lead to decreased fruit set and yield in tomato plants. GDP-L-galactose phosphorylase (GGP) catalyzes the first step committed to ascorbic acid synthesis. The participation of GDP-L-galactose phosphorylase and ascorbate in tomato fruit production and quality was studied in this work using two SlGGP1 deficient EMS Micro-Tom mutants. The SlGGP1 mutants display decreased concentrations of ascorbate in roots, leaves, flowers, and fruit. The initiation of anthesis is delayed in ggp1 plants but the number of flowers is similar to wild type. The number of fruits is reduced in ggp1 mutants with an increased individual weight. However, the whole fruit biomass accumulation is reduced in both mutant lines. Fruits of the ggp1 plants produce more ethylene and show higher firmness and soluble solids content than the wild type after the breaker stage. Leaf CO2 uptake decreases about 50% in both ggp1 mutants at saturating light conditions; however, O2 production in an enriched CO2 atmosphere is only 19% higher in wild type leaves. Leaf conductance that is largely reduced in both mutants may be the main limitation for photosynthesis. Sink-source assays and hormone concentration were measured to determine restrictions to fruit yield. Manipulation of leaf area/fruit number relationship demonstrates that the number of fruits and not the provision of photoassimilates from the source restricts biomass accumulation in the ggp1 lines. The lower gibberellins concentration measured in the flowers would contribute to the lower fruit set, thus impacting in tomato yield. Taken as a whole these results demonstrate that ascorbate biosynthetic pathway critically participates in tomato development and fruit production.ANPCyTUniversidad Nacional de La Plata, Argentin

Light-driven chloride transport kinetics of halorhodopsin

Despite growing interest in light-driven ion pumps for use in optogenetics, current estimates of their transport rates span two orders of magnitude due to challenges in measuring slow transport processes and determining protein concentration and/or orientation in membranes in vitro. In this study, we report, to our knowledge, the first direct quantitative measurement of light-driven Cl transport rates of the anion pump halorohodopsin from Natronomonas pharaonis (NpHR). We used light-interfaced voltage clamp measurements on NpHR-expressing oocytes to obtain a transport rate of 219 (± 98) Cl /protein/s for a photon flux of 630 photons/protein/s. The measurement is consistent with the literature-reported quantum efficiency of ∼30% for NpHR, i.e., 0.3 isomerizations per photon absorbed. To reconcile our measurements with an earlier-reported 20 ms rate-limiting step, or 35 turnovers/protein/s, we conducted, to our knowledge, novel consecutive single-turnover flash experiments that demonstrate that under continuous illumination, NpHR bypasses this step in the photocycle