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At least 379 records · Page 21

Genome Sequences of Frankineae sp. Strain MT45 and Jatrophihabitans sp. Strain GAS493, Two Actinobacteria Isolated from Forest Soil

Frankiaceae are bacterial endosymbionts that are also found free-living in soil. Here, we present the genome sequences of two novel bacterial members of the order Frankiales , class Actinobacteria , isolated from temperate terrestrial forest soils. The genomes for MT45 and GAS493 indicate a genetic capacity for carbohydrate degradation but not nitrogen fixation.

DeAngelis, Kristen M.↗

Progress Summary: Simulating stochastic and additively manufactured foams at large strains and high strain rates

Motivation: Understanding the mechanical response of polymer foams is essential in developing system material models and in designing replacements for legacy pads and cushions. Simulations can help elucidate structure-property relationships and compare local stress distributions to understand aging behavior and improve designs. In many applications,these materials experience significant loadings and computations need the capability to reproduce those conditions. Significance: In designing the compressive and shear response of additively manufactured foams, we expect the curvature of the substrate to influence their mechanical behavior. Progress:We have the capability of mapping planar structures to arbitrary curved surfaces and are currently developing the software and procedures to translate the mapped pattern into a geometrical model that can be imported to either finite element or material point software to evaluate the mechanical response. Figure 1 depicts a four-layer face-centered tetragonal pattern (FCT) mapped to a hemispherical surface. Because the mapping cannot exactly preserve both distances and angles, we expect some local variation in mechanical properties and porosity. These models will help determine the sensitivity of these variations to structure and curvature, optimize the mapping procedure, and inform the design of foams for non-planar surfaces.

36 MATERIALS SCIENCE↗

Simulating stochastic and additively manufactured foams at large strains and high strain rates

Understanding the mechanical response of polymer foams is essential in developing system material models and in designing replacements for legacy pads and cushions. Simulations can help elucidate structure-property relationships and compare local stress distributions to understand aging behavior and improve designs. In many applications, these materials experience significant loadings and computations need the capability to reproduce those conditions. We are applying are previously developed material point method (MPM) simulation capability to understand the aging properties of loaded direct ink write (DIW) resins.

36 MATERIALS SCIENCE↗

Simulating stochastic and additively manufactured foams at large strains and high strain rates (Progress Summary)

Understanding the mechanical response of polymer foams is essential in developing system material models and in designing replacements for legacy pads and cushions. Simulations can help elucidate structure-property relationships and compare local stress distributions to understand aging behavior and improve designs. In many applications, these materials experience significant loadings and computations need the capability to reproduce those conditions. We are applying are previously developed material point method (MPM) simulation capability to understand the aging properties of loaded direct ink write resins. Significant particle loading of a stiffer material in siloxane networks exhibit different compression set behavior than unloaded specimens. We are applying our computational mechanics capabilities to understand this difference at the continuum level. Figure 1 highlights preliminary results, depicting renderings of an unloaded DIW filament alongside one containing a 20% volume loading of spherical particles. Also, the stress distribution of a neat filament at 20% compression is shown. We are planning to study this behavior for a range of loading fractions, particle sizes, and material stiffness ratios. We will explore the sensitivity of the stress response to these variables which could inform aging models of these materials.

36 MATERIALS SCIENCE↗

Simulating stochastic and additively manufactured foams at large strains and high strain rates

Understanding the mechanical response of polymer foams is essential in developing system material models and in designing replacements for legacy pads and cushions. Simulations can help elucidate structure-property relationships and compare local stress distributions to understand aging behavior and improve designs. In many applications, these materials experience significant loadings and computations need the capability to reproduce those conditions.

36 MATERIALS SCIENCE↗

Genome sequence of the orange-pigmented seawater bacterium Owenweeksia hongkongensis type strain (UST20020801 T )

Owenweeksia hongkongensis Lau et al. 2005 is the sole member of the monospecific genus Owenweeksia in the family Cryomorphaceae, a poorly characterized family at the genome level thus far. This family comprises seven genera within the class Flavobacteria. Family members are known to be psychrotolerant, rod-shaped and orange pigmented (β-carotene), typical for Flavobacteria. For growth, seawater and complex organic nutrients are necessary. The genome of O. hongkongensis UST20020801 T is only the second genome of a member of the family Cryomorphaceae whose sequence has been deciphered. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,000,057 bp long chromosome with its 3,518 protein-coding and 45 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

orange-pigmented sea water↗

Genome sequence of the free-living aerobic spirochete Turneriella parva type strain (H T ), and emendation of the species Turneriella parva

Turneriella parva Levett et al. 2005 is the only species of the genus Turneriella which was established as a result of the reclassification of Leptospira parva Hovind-Hougen et al. 1982. Together with Leptonema and Leptospira, Turneriella constitutes the family Leptospiraceae, within the order Spirochaetales. Here we describe the features of this free-living aerobic spirochete together with the complete genome sequence and annotation. This is the first complete genome sequence of a member of the genus Turneriella and the 13(th) member of the family Leptospiraceae for which a complete or draft genome sequence is now available. The 4,409,302 bp long genome with its 4,169 protein-coding and 45 RNA genes is part of the G enomic E ncyclopedia of Bacteria and Archaea project.

59 BASIC BIOLOGICAL SCIENCES↗