Differential geometry construction of anomalies and topological invariants in various dimensions

In the model of extended non-Abelian tensor gauge fields we have found new metric-independent densities: the exact (2n+3)-forms and their secondary characteristics, the (2n+2)-forms as well as the exact 6n-forms and the corresponding secondary (6n-1)-forms. These forms are the analogs of the Pontryagin densities: the exact 2n-forms and Chern-Simons secondary characteristics, the (2n-1)-forms. The (2n+3)- and 6n-forms are gauge invariant densities, while the (2n+2)- and (6n-1)-forms transform non-trivially under gauge transformations, that we compare with the corresponding transformations of the Chern-Simons secondary characteristics. This construction allows to identify new potential gauge anomalies in various dimensions.Comment: 27 pages, references added, matches published versio

Exposure Path Perceptions and Protective Actions in Biological Water Contamination Emergencies

This study extends the Protective Action Decision Model, developed to address disaster warning responses in the context of natural hazards, to “boil water” advisories. The study examined 110 Boston residents’ and 203 Texas students’ expectations of getting sick through different exposure paths for contact with contaminated water. In addition, the study assessed respondents’ actual implementation (for residents) or behavioral expectations (for students) of three different protective actions – bottled water, boiled water, and personally chlorinated water – as well as their demo-graphic characteristics and previous experience with water contamination. The results indicate that people distinguish among the exposure paths, but the differences are small (one-third to one-half of the response scale). Nonetheless, the perceived risk from the exposure paths helps to explain why people are expected to consume (or actually consumed) bottled water rather than boiled or personally chlorinated water. Overall, these results indicate that local authorities should take care to communicate the relative risks of different exposure paths and should expect that people will respond to a boil water order primarily by consuming bottled water. Thus, they should make special efforts to increase supplies of bottled water in their communities during water contamination emergencies

Investigating magmatic processes in the early Solar System using the Cl isotopic systematics of eucrites

Generally, terrestrial rocks, martian and chondritic meteorites exhibit a relatively narrow range in bulk and apatite Cl isotope compositions, with δ37Cl (per mil deviation from standard mean ocean chloride) values between − 5.6 and + 3.8 ‰. Lunar rocks, however, have more variable bulk and apatite δ37Cl values, ranging from ∼ − 4 to + 40 ‰. As the Howardite-Eucrite-Diogenite (HED) meteorites represent the largest suite of crustal and sub-crustal rocks available from a differentiated basaltic asteroid (4 Vesta), studying them for their volatiles may provide insights into planetary differentiation processes during the earliest Solar System history. Here the abundance and isotopic composition of Cl in apatite were determined for seven eucrites representing a broad range of textural and petrological characteristics. Apatite Cl abundances range from ∼ 25 to 4900 ppm and the δ37Cl values range from − 3.98 to + 39.2 ‰. Samples with lower apatite H2O contents were typically also enriched in 37Cl but no systematic correlation between δ37Cl and δD values was observed across samples. Modelled Rayleigh fractionation and a strong positive correlation between bulk δ66Zn and apatite δ37Cl support the hypothesis that Cl degassed as metal chlorides from eucritic magmas, in a hydrogen-poor environment. In the case of lunar samples, it has been noted that δ37Cl values of apatite positively correlate with bulk La/Yb ratio. Interestingly, most eucrites show a negative correlation with bulk La/Yb ratio. Recently, isotopically light Cl values have been suggested to record the primary solar nebular signature. If this is the case then 4 Vesta, which accreted rapidly and early in Solar System history, could also record this primary nebular signature corresponding to the lightest Cl values measured here. The significant variation in Cl isotope composition observed within the eucrites are likely related to degassing of metal chlorides

Core Formation and Mantle Differentiation on Mars

info:eu-repo/semantics/publishe