Oil cooling system for a gas turbine engine

A gas turbine engine fuel delivery and control system is provided with means to recirculate all fuel in excess fuel control requirements back to the aircraft fuel tank. This increases the fuel pump heat sink and decreases the pump temperature rise without the addition of valving other than normally employed. A fuel/oil heat exchanger and associated circuitry is provided to maintain the hot engine oil in heat exchange relationship with the cool engine fuel. Where anti-icing of the fuel filter is required, means are provided to maintain the fuel temperature entering the filter at or above a minimum level to prevent freezing thereof. In one embodiment, a divider valve is provided to take all excess fuel from either upstream or downstream of the fuel filter and route it back to the tanks, the ratio of upstream to downstream extraction being a function of fuel pump discharge pressure

Non-Linear Asset Valuation on Markets with Frictions

This paper provides a non-linear pricing rule for the valuation of assets on financial markets with intermediaries.The non-linearity arises from the fact that dealers charge a price for their intermediation between buyer and seller. The pricing rule we propose is an alternative for the wellknown no-arbitrage pricing on markets without frictions.The price of an asset equals the signed Choquet integral of its discounted payo with respect to a concave signed capacity.We show that this pricing rule is consistent with equilibrium. Furthermore, equilibria are shown to satisfy a notion of constrained Pareto optimality.game theory;duopoly

Finding nondestructive parameters for root-to-shoot ratios in douglas-fir, grand fir, and redwood saplings in Northwest California for biomass and carbon storage estimates

ABSTRACT FINDING NONDESTRUCTIVE PARAMETERS FOR ROOT-TO-SHOOT RATIOS IN DOUGLAS-FIR, GRAND FIR, AND REDWOOD SAPLINGS IN NORTHWEST CALIFORNIA FOR BIOMASS AND CARBON STORAGE ESTIMATES Walter A. Kast There is a need for better understanding of how woody biomass is allocated above and belowground and how this allocation might differ among tree species. In this field of research, investigators face challenges such as the laborious task of removing trees from the soil with destructive sampling, and the cleaning, drying, and weighing of belowground biomass (BGB). Therefore, researchers and practitioners most often rely on existing models to predict BGB from easily-measurable aboveground variables such as stem diameter and height. Such models have been developed for many tree species, but commonly these models require inputs of diameter at breast height (dbh) and are not designed to make predictions for younger saplings (i.e., below 5 cm dbh). To fill knowledge gaps in young conifer BGB allocation, we studied three conifers native to the north coast of California: coast redwood (Sequoia sempervirens), coast Douglas-fir (Pseudotsuga menziesii var menziesii), and grand fir (Abies grandis). We sought to determine: (i) Does the root-to-shoot ratio differ between the three species Douglas-fir, grand fir, and coast redwood in afforestation plots? (ii) Does the root-to-shoot ratio of the three species differ according to age (i.e. sampling across a span of three years?) (iii) Does the competing flora alter the root-to-shoot ratio of any of the three species? (iv) What are the best “easily-measurable” aboveground variables to be included in prediction equations for BGB in the three tree species? Experimental plots were planted in 2008/09, and another in 2009/10 at the L. W. Schatz Demonstration Tree Farm located in Humboldt County, CA. Five species were planted: coast redwood, coast Douglas-fir, grand fir, red alder (Alnus rubra), and black cottonwood (Populus balsamifera). Redwood, Douglas-fir, and grand fir were destructively sampled for BGB measurement. A random sample of these three species were excavated by hand, and separated into three sections: stems, roots and branches. Each species had 24 trees sampled across the 3 years of data collection for a total of 72 trees. The sapling biomass components were weighed, dried in an oven, and re-weighed to determine bone dry weight and root-to-shoot biomass ratios. Before final root-to-shoot ratios and BGB models were created, auxiliary models were developed to predict the weight of any roots that were broken off during the excavation of the saplings. Models for severed root weight were tested against sapling height, average crown width, lower crown base height, and stem diameter. Results showed high correlation between root weight and stem diameter at ground line (caliper, mm). Exponential models made the best predictions of weight of individual pieces of broken root for all three species: Douglas-fir (R2= 0.86), grand fir (R2= 0.91), and redwood (R2= 0.79). After missing root weights had been predicted for each broken root on the root system of each sample tree, summed, and added to the overall root mass, equations to predict BGB were developed and tested. Multivariable models were tested for all three species, but showed no statistical significance. Bivariate regressions of BGB as function of tree height (cm), average crown width (cm), lower crown base height (cm), stem diameter (mm), year, and percent cover of competing flora were tested. In species-specific bivariate regressions, tree height, average crown width, and stem diameter were all found to be statistically significant predictors of BGB for all three species. Douglas-fir BGB was best predicted with a linear model utilizing caliper as the explanatory variable (R2= 0.77). Grand fir BGB was also predicted well by a linear model with caliper as the explanatory variable (R2= 0.92). Redwood BGB exhibited an exponential relationship with caliper (R2= 0.91). Root-to-shoot ratios for the three species averaged between 0.27 and 0.46. All variables tested for BGB were also tested as predictor of root-to-shoot ratios, however for Douglas-fir and grand fir, no significant relationships between root-to-shoot ratio and the candidate predictor variables were found. For redwood, stem diameter, average crown width, and sapling height all were significant predictors of root-to-shoot ratio. Redwood sapling height was the best predictor of root-to-shoot ratio (R2= 0.37). For all three species, ANOVA tested for differences in root-to-shoot ratios among sample ages. The youngest Douglas-fir saplings (three years old) had higher root-to-shoot ratio than the five and seven year old trees. Grand fir showed no differences in root-to-shoot ratios according to age. Redwood root-to-shoot ratios were significantly different between ages three and four, between ages four and five, and between ages four and six years old

Computer processing support, volume 4

There are no author-identified significant results in this report

Non-Linear Asset Valuation on Markets with Frictions

This paper provides a non-linear pricing rule for the valuation of assets on financial markets with intermediaries.The non-linearity arises from the fact that dealers charge a price for their intermediation between buyer and seller. The pricing rule we propose is an alternative for the wellknown no-arbitrage pricing on markets without frictions.The price of an asset equals the signed Choquet integral of its discounted payo with respect to a concave signed capacity.We show that this pricing rule is consistent with equilibrium. Furthermore, equilibria are shown to satisfy a notion of constrained Pareto optimality.

ECHO user's guide

There are no author-identified significant results in this report

The NTPase activity of the double FYVE domain-containing protein 1 regulates lipid droplet metabolism.

Lipid droplets (LDs) are transient lipid storage organelles that can be readily tapped to resupply cells with energy or lipid building blocks and therefore play a central role in cellular metabolism. However, the molecular factors and underlying mechanisms that regulate the growth and degradation of LDs are poorly understood. It has emerged that proteins that establish contacts between LDs and the endoplasmic reticulum play a critical role in regulating LD metabolism. Recently, the autophagy-related protein, double FYVE domain-containing protein 1 (DFCP1/ZFYVE1) was shown to reside at the interface of the endoplasmic reticulum and LDs, however, little is known about the involvement of DFCP1 in autophagy and LD metabolism. Here, we show that DFCP1 is a novel NTPase that regulates free fatty acid metabolism. Specifically, we show that DFPC1-knockdown, particularly during starvation, increases cellular free fatty acids and decreases the levels of cellular TAGs, resulting in accumulated small LDs. Using selective truncations, we demonstrate that DFCP1 accumulation on LDs in cells and in vitro is regulated by a previously unknown NTPase domain. Using spectroscopic approaches, we show that this NTPase domain can dimerize and can hydrolyze both ATP and GTP. Furthermore, mutations in DFCP1 that either impact nucleotide hydrolysis or dimerization result in changes in the accumulation of DFCP1 on LDs, changes in LD density and size, and colocalization of LDs to autophagosomes. Collectively, our findings suggest that DFCP1 is an NTPase that modulates the metabolism of LDs in cells

Efficient introduction of aryl bromide functionality into proteins in vivo

Artificial proteins can be engineered to exhibit interesting solid state, liquid crystal or interfacial properties and may ultimately serve as important alternatives to conventional polymeric materials. The utility of protein-based materials is limited, however, by the availability of just the 20 amino acids that are normally recognized and utilized by biological systems; many desirable functional groups cannot be incorporated directly into proteins by biosynthetic means. In this study, we incorporate para-bromophenylalanine (p-Br-phe) into a model target protein, mouse dihydrofolate reductase (DHFR), by using a bacterial phenylalanyl-tRNA synthetase (PheRS) variant with relaxed substrate specificity. Coexpression of the mutant PheRS and DHFR in a phenylalanine auxotrophic Escherichia coli host strain grown in p-Br-phe-supplemented minimal medium resulted in 88% replacement of phenylalanine residues by p-Br-phe; variation in the relative amounts of phe and p-Br-phe in the medium allows control of the degree of substitution by the analog. Protein expression yields of 20–25 mg/l were obtained from cultures supplemented with p-Br-phe; this corresponds to about two-thirds of the expression levels characteristic of cultures supplemented with phe. The aryl bromide function is stable under the conditions used to purify DHFR and creates new opportunities for post-translational derivatization of brominated proteins via metal-catalyzed coupling reactions. In addition, bromination may be useful in X-ray studies of proteins via the multiwavelength anomalous diffraction (MAD) technique