We propose that the indirect adatom-adatom interaction mediated by the conduction electrons of a metallic surface is responsible for the sqrt[3]xsqrt[3]<==>3x3 structural phase transitions observed in Sn/Ge (111) and Pb/Ge (111). When the indirect interaction overwhelms the local stress field imposed by the substrate registry, the system suffers a phonon instability, resulting in a structural p...

The existence of ancient rocks in present mid-ocean ridges have long been observed but received less attention. Here we report the discovery of zircons with both reasonably young ages of about 5 Ma and abnormally old ages of approximate 180 Ma from two evolved gabbroic rocks that were dredged from the Southwest Indian Ridge (SWIR) in the Gallieni fracture zone. U-Pb and Lu-Hf isotope analyses o...

Introduction Let C be a convex bounded body in the n-dimensional Euclidean space E, and let B be its boundary. We use Busemann's notations: E(a,b) for the segment {(1 — p)a + pb: 0 < p ^ 1} from a to b, and S(z, p) for the sphere {x: \\z — x\\ = p). We now recall the definition of Hammer's associated bodies C(r). Let Cb(r) be the set obtained from C by a similitude transformation with a ratio r...

mRNA accumulation is tightly regulated by diverse molecular pathways. The identification and characterization of enzymes and regulatory proteins involved in controlling the fate of mRNA offers the possibility to broaden our understanding of posttranscriptional gene regulation. Processing bodies (P bodies, PB) are cytoplasmic protein complexes involved in degradation and translational arrest of ...

Travel by commercial jet aircraft is a popular, expeditious, safe and generally affordable mode of transportation. Millions of passengers fly all over the world every year. A proportion of them are disabled, or have experienced recent injury or illness. Despite the comfort and convenience of modern commercial aircraft, there are environmental factors that may affect some persons, particularly t...

This paper evaluates the role of minor component polybenzoxazine (PB) on shape-memory properties of polyurethanes (PU) with glassy and crystalline soft segments. The polymer compounds were prepared in two steps. In the first step, benzoxazine, polyurethane pre-polymer, and chain extender butanediol (BD) were mixed into a solution followed by chain-extension of the pre-polymer with BD. In the se...

Shoot biomass production, alkaloid content and composition as influence by cadmium, manganese, nickel and lead at uniform dose of 5 mM were investigated in Catharanthus roseus plants grown in sand culture. Treatment with Mn, Ni, and Pb significantly enhanced total root alkaloid accumulation. Cd and Ni treatment resulted in two-fold where as Pb treatment resulted in three fold increase in serpen...

Plants, in general, are put to various kinds of stress, biotic and abiotic, both natural and manmade. Infestation by insect pests and diseases, and extreme conditions such as salinity, temperature, etc., as well as heavy metal contamination affect their growth performance. Here, we studied the impact of salinity and heavy metal pollution on the growth performance of Indian Mustard Brassica junc...

abstract nowadays, environmental pollution by heavy metals is one of the most serious threats of the world which needs effective remediation actions. the aim of this study was to investigate the potential use of atriplex [atriplex verucifera], salicornia [salicornia europaea] and chenopodium album in simultaneous uptake and accumulation of na and cd or pb in two calcareous soils with different ...