Biomechanical characterization of the passive response of the thoracic aorta in chronic hypoxic newborn lambs using an evolutionary strategy

AbstractThe present study involves experiments and modelling aimed at characterizing the passive structural mechanical behavior of the chronic hypoxic lamb thoracic aorta, whose gestation, birth and postnatal period were carried at high altitude (3600 masl). To this end, the mechanical response was studied via tensile and pressurization tests. The tensile and pressurization tests measurements were used simultaneously to calibrate the material parameters of the Gasser–Holzapfel–Ogden (GHO) hyperelasctic anisotropic constitutive model through an analytical-numerical optimization procedure solved with an evolutionary strategy that guarantees a stable response of the model. The model and procedure of calibration adequately adjust to the material behavior in a wide deformation range with an appropriate physical description. The results of this study predict the mechanical response of the lamb thoracic aorta under generalized loading states like those that can occur in physiological conditions and/or in systemic arterial hypertension. Finally, the novel use of the evolutionary strategy, together with the set of experiments and tools used in this study, provide a robust alternative to validate biomechanical characterizations.

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Identification and characterization of diverse OTU deubiquitinases in bacteria

10.1101/2020.03.28.013474 ◽

2020 ◽

Author(s):

Alexander F. Schubert ◽

Justine V. Nguyen ◽

Tyler G. Franklin ◽

Paul P. Geurink ◽

Cameron G. Roberts ◽

...

Keyword(s):

Immune Response ◽

Ovarian Tumor ◽

Pathogenic Bacteria ◽

Evolutionary Strategy ◽

The Novel ◽

Viral Pathogens ◽

Biochemical Assays ◽

Host Signaling ◽

Identification And Characterization

ABSTRACTManipulation of host ubiquitin signaling is becoming an increasingly apparent evolutionary strategy among bacterial and viral pathogens. By removing host ubiquitin signals, for example, invading pathogens can inactivate immune response pathways and evade detection. The Ovarian Tumor (OTU) family of deubiquitinases regulates diverse ubiquitin signals in humans. Viral pathogens have also extensively co-opted the OTU fold to subvert host signaling, but the extent to which bacteria utilize the OTU fold was unknown. We have predicted and validated a set of OTU deubiquitinases encoded by several classes of pathogenic bacteria. Biochemical assays highlight the ubiquitin and polyubiquitin linkage specificities of these bacterial deubiquitinases. By determining the ubiquitin-bound structures of two examples, we demonstrate the novel strategies that have evolved to both thread an OTU fold and to recognize a ubiquitin substrate. With these new examples, we perform the first cross-kingdom structural analysis of the OTU fold that highlights commonalities among distantly-related OTU deubiquitinases.

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Construction of plastic contact deformation maps on ceramics: a case study on aluminum nitride

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165641 ◽

1996 ◽

Vol 54 ◽

pp. 636-637

Author(s):

D. L. Callahan

Keyword(s):

Plastic Deformation ◽

Aluminum Nitride ◽

Mechanical Response ◽

Three Dimensional ◽

Bright Field Image ◽

Perfectly Plastic ◽

Contrast Analysis ◽

Deformation Patterns

Modern polishing, precision machining and microindentation techniques allow the processing and mechanical characterization of ceramics at nanometric scales and within entirely plastic deformation regimes. The mechanical response of most ceramics to such highly constrained contact is not predictable from macroscopic properties and the microstructural deformation patterns have proven difficult to characterize by the application of any individual technique. In this study, TEM techniques of contrast analysis and CBED are combined with stereographic analysis to construct a three-dimensional microstructure deformation map of the surface of a perfectly plastic microindentation on macroscopically brittle aluminum nitride.The bright field image in Figure 1 shows a lg Vickers microindentation contained within a single AlN grain far from any boundaries. High densities of dislocations are evident, particularly near facet edges but are not individually resolvable. The prominent bend contours also indicate the severity of plastic deformation. Figure 2 is a selected area diffraction pattern covering the entire indentation area.

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Characterization of the novel aspartic proteinases, BACE and BACE2

Neuroscience Research ◽

10.1016/s0168-0102(00)81592-8 ◽

2000 ◽

Vol 38 ◽

pp. S124

Author(s):

S Kametaka

Keyword(s):

The Novel ◽

Aspartic Proteinases

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Characterization of the novel HLA‐C *07:944 allele by next‐generation sequencing

HLA ◽

10.1111/tan.14281 ◽

2021 ◽

Author(s):

Maria Loginova ◽

Olga Makhova ◽

Daria Smirnova ◽

Igor Paramonov ◽

Maksim Zarubin

Keyword(s):

Next Generation Sequencing ◽

The Novel ◽

Next Generation ◽

Generation Sequencing

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Characterization of the novel HLA‐B *51:296 allele by next‐generation sequencing

HLA ◽

10.1111/tan.14074 ◽

2020 ◽

Author(s):

Steve Genebrier ◽

Vincent Elsermans ◽

Emeric Texeraud ◽

Gerald Bertrand ◽

Virginie Renac

Keyword(s):

Next Generation Sequencing ◽

The Novel ◽

Next Generation ◽

Generation Sequencing

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Characterization of the novel HLA‐DRB1*11:282 allele by sequencing‐based typing

HLA ◽

10.1111/tan.14308 ◽

2021 ◽

Author(s):

Marine Cargou ◽

Vincent Elsermans ◽

Isabelle Top ◽

Laura Blouin ◽

Jonathan Visentin

Keyword(s):

The Novel

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Isolation and Characterization of Salmonella Jumbo-Phage pSal-SNUABM-04

Viruses ◽

10.3390/v13010027 ◽

2020 ◽

Vol 13 (1) ◽

pp. 27

Author(s):

Jun Kwon ◽

Sang Guen Kim ◽

Hyoun Joong Kim ◽

Sib Sankar Giri ◽

Sang Wha Kim ◽

...

Keyword(s):

Morphological Traits ◽

Open Reading Frames ◽

Genome Comparison ◽

The Novel ◽

Promising Alternative ◽

Isolation And Characterization ◽

Global Issue ◽

Reading Frames ◽

Predicted Function

The increasing emergence of antimicrobial resistance has become a global issue. Therefore, many researchers have attempted to develop alternative antibiotics. One promising alternative is bacteriophage. In this study, we focused on a jumbo-phage infecting Salmonella isolated from exotic pet markets. Using a Salmonella strain isolated from reptiles as a host, we isolated and characterized the novel jumbo-bacteriophage pSal-SNUABM-04. This phage was investigated in terms of its morphology, host infectivity, growth and lysis kinetics, and genome. The phage was classified as Myoviridae based on its morphological traits and showed a comparatively wide host range. The lysis efficacy test showed that the phage can inhibit bacterial growth in the planktonic state. Genetic analysis revealed that the phage possesses a 239,626-base pair genome with 280 putative open reading frames, 76 of which have a predicted function and 195 of which have none. By genome comparison with other jumbo phages, the phage was designated as a novel member of Machinavirus composed of Erwnina phages.

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Material parametrization of natural rubber based compound and characterization of crack propagation under consideration of dissipative effects

Journal of Rubber Research ◽

10.1007/s42464-021-00094-8 ◽

2021 ◽

Author(s):

Dan Pornhagen ◽

Konrad Schneider ◽

Markus Stommel

Keyword(s):

Energy Dissipation ◽

Crack Propagation ◽

Natural Rubber ◽

Experimental Tests ◽

Material Behavior ◽

Prony Series ◽

Material Forces ◽

Cracking Behavior ◽

Dissipative Effects

AbstractMost concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.

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