Applying laboratory methods for durability assessment of vitrified material to archaeological samples

Laboratory testing used to assess the long-term chemical durability of nuclear waste forms may not be applicable to disposal because the accelerated conditions may not represent disposal conditions. To address this, we examine the corrosion of vitrified archeological materials excavated from the near surface of a ~1500-year old Iron Age Swedish hillfort, Broborg, as an analog for the disposal of vitrified nuclear waste. We compare characterized site samples with corrosion characteristics generated by standard laboratory durability test methods including the product consistency test (PCT), the vapor hydration test (VHT), and the EPA Method 1313 test. Results show that the surficial layer of the Broborg samples resulting from VHT displays some similarities to the morphology of the surficial layer formed over longer timescales in the environment. This work provides improved understanding of long-term glass corrosion behavior in terms of the thickness, morphology, and chemistry of the surficial features that are formed

RELAP/FRAP-T6 analysis of seized and sheared shaft accidents. [PWR]

Argonne National Laboratory (ANL) performed audit calculations of a Reactor Coolant Pump (RCP) seized/sheared shaft transient for the Westinghouse Seabrook Plant using RELAP5/MOD 1.5 (Cycle 32) and FRAP-T6. The objective was to determine the effect of time of loss of offsite power and other single component failures on the peak clad temperature. The RCP shaft seizure event was modeled in RELAP5 by using the pump model shaft stop option. In modeling the sheared shaft failure, the faulted pump was replaced with a branch component having no flow losses. In general, the RELAP5-predicted system response for the seized shaft transient was very comparable to the results presented in the Seabrook FSAR, although the Reactor Coolant System (RCS) pressure response was somewhat different. The RELAP5 sheared-shaft analysis results were very similar to those for the seized shaft

Thrombospondin-1 as a Regulator of Corneal Inflammation and Lymphangiogenesis: Effects on Dry Eye Disease and Corneal Graft Immunology

Thrombospondin-1 (TSP-1) is a matricellular glycoprotein that belongs to a family of evolutionary highly conserved calcium-binding proteins consisting of 5 members (TSP-1-TSP-5). In the eye, TSP-1 is expressed by several ocular cell types and is also detectable in the aqueous humor and the vitreous body. So far, TSP-1 is one of the major activators of TGF beta, suggesting a strong influence on various important cellular functions and interactions such as differentiation, migration, and wound healing. TSP-1 is also a key endogenous inhibitor of hem- and lymphangiogenesis. Several lines of evidence indicate a crucial role of TSP-1 in maintaining the ocular immune and angiogenic privilege, for example, by regulating T lymphocytes and the tolerance-promoting properties of ocular antigen-presenting cells. This review discusses the role of TSP-1 in dry eye disease and corneal graft rejection through its effects on hem- and lymphangiogenesis, as well as on the underlying immune responses. Recent work will be reviewed showing by which molecular mechanism TSP-1 modulates inflammatory processes during ocular diseases. This opens potential new treatment avenues in inflammatory and (lymph)angiogenic ocular diseases