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The differentiation of naive CD8+ T cells into effector cells is important for establishing immunity. However, the effect of heterogeneous naive CD8+ T cell populations is not fully understood. Here, we demonstrate that steady-state naive CD8+ T cells are composed of functionally heterogeneous subpopulations that differ in their ability to differentiate into type 17 cytotoxic effector cells (Tc17) in a context of murine inflammatory disease models, such as inflammatory bowel disease and graft-versus-host disease. The differential ability of Tc17 differentiation is not related to T-cell receptor (TCR) diversity and antigen specificity but is inversely correlated with self-reactivity acquired during development. Mechanistically, this phenomenon is linked to differential levels of intrinsic TCR sensitivity and basal Suppressor of Mothers Against Decapentaplegic 3 (SMAD3) expression, generating a wide spectrum of Tc17 differentiation potential within naive CD8+ T cell populations. These findings suggest that developmental self-reactivity can determine the fate of naive CD8+ T cells to generate functionally distinct effector populations and achieve immense diversity and complexity in antigen-specific T-cell immune responses.

This study examined the effects of thermomechanical processing and subsequent conventional heat treatment on microstructure and fatigue in AISI 52100 steel. The thermomechanical processing techniques are essentially those described by Sherby and his co-workers at Stanford University. Previous research by that group and at the Naval Postgraduate School has demonstrated that a wide range of ferrite matrix grain sizes and carbide particle distributions can be obtained in this steel. Studies parallel with this are examining the subsequent heat treatment response of these structures and also the fracture toughness attainable. In this study on fatigue, it was found that both the fatigue life at a given cyclic stress and the endurance limit were improved by processing to produce an ultra-fine grained ferrite-carbide microstructure prior to heat treatment. Improvement in fatigue resistance was especially pronounced when the material was heat treated to fine Bainitic, rather than Martensitic microstructures . These improvements are postulated to result from changes in crack propagation mode and improved resistance to fatigue crack propagation., http://archive.org/details/theinfluenceofrm1094518761, This thesis prepared in conjunction with research supported in part by the Naval Sea Systems Command under work request N0002479-WR9G078., Commander, Republic of Korea Navy, Approved for public release; distribution is unlimited.

There has been a good deal of interest in the potential of marine vegetation as a sink for anthropogenic C emissions (“Blue Carbon”). Marine primary producers contribute at least 50% of the world’s carbon fixation and may account for as much as 71% of all carbon storage. In this paper, we analyse the current rate of harvesting of both commercially grown and wild-grown macroalgae, as well as their capacity for photosynthetically driven CO2 assimilation and growth. We suggest that CO2 acquisition by marine macroalgae can represent a considerable sink for anthropogenic CO2 emissions and that harvesting and appropriate use of macroalgal primary production could play a significant role in C sequestration and amelioration of greenhouse gas emissions.

There has been a good deal of interest in the potential of marine vegetation as a sink for anthropogenic C emissions (“Blue Carbon”). Marine primary producers contribute at least 50% of the world’s carbon fixation and may account for as much as 71% of all carbon storage. In this paper, we analyse the current rate of harvesting of both commercially grown and wild-grown macroalgae, as well as their capacity for photosynthetically driven CO2 assimilation and growth. We suggest that CO2 acquisition by marine macroalgae can represent a considerable sink for anthropogenic CO2 emissions and that harvesting and appropriate use of macroalgal primary production could play a significant role in C sequestration and amelioration of greenhouse gas emissions.

This study examined the effects of thermomechanical processing and subsequent conventional heat treatment on microstructure and fatigue in AISI 52100 steel. The thermomechanical processing techniques are essentially those described by Sherby and his co-workers at Stanford University. Previous research by that group and at the Naval Postgraduate School has demonstrated that a wide range of ferrite matrix grain sizes and carbide particle distributions can be obtained in this steel. Studies parallel with this are examining the subsequent heat treatment response of these structures and also the fracture toughness attainable. In this study on fatigue, it was found that both the fatigue life at a given cyclic stress and the endurance limit were improved by processing to produce an ultra-fine grained ferrite-carbide microstructure prior to heat treatment. Improvement in fatigue resistance was especially pronounced when the material was heat treated to fine Bainitic, rather than Martensitic microstructures. These improvements are postulated to result from changes in crack propagation mode and improved resistance to fatigue crack propagation. (Author)

This study examined the effects of thermomechanical processing and subsequent conventional heat treatment on microstructure and fatigue in AISI 52100 steel. The thermomechanical processing techniques are essentially those described by Sherby and his co-workers at Stanford University. Previous research by that group and at the Naval Postgraduate School has demonstrated that a wide range of ferrite matrix grain sizes and carbide particle distributions can be obtained in this steel. Studies parallel with this are examining the subsequent heat treatment response of these structures and also the fracture toughness attainable. In this study on fatigue, it was found that both the fatigue life at a given cyclic stress and the endurance limit were improved by processing to produce an ultra-fine grained ferrite-carbide microstructure prior to heat treatment. Improvement in fatigue resistance was especially pronounced when the material was heat treated to fine Bainitic, rather than Martensitic microstructures . These improvements are postulated to result from changes in crack propagation mode and improved resistance to fatigue crack propagation.

This study examined the effects of thermomechanical processing and subsequent conventional heat treatment on microstructure and fatigue in AISI 52100 steel. The thermomechanical processing techniques are essentially those described by Sherby and his co-workers at Stanford University. Previous research by that group and at the Naval Postgraduate School has demonstrated that a wide range of ferrite matrix grain sizes and carbide particle distributions can be obtained in this steel. Studies parallel with this are examining the subsequent heat treatment response of these structures and also the fracture toughness attainable. In this study on fatigue, it was found that both the fatigue life at a given cyclic stress and the endurance limit were improved by processing to produce an ultra-fine grained ferrite-carbide microstructure prior to heat treatment. Improvement in fatigue resistance was especially pronounced when the material was heat treated to fine Bainitic, rather than Martensitic microstructures . These improvements are postulated to result from changes in crack propagation mode and improved resistance to fatigue crack propagation.