In this paper we discuss abundance ratios and their relation to stellar nucleosynthesis and other parameters of chemical evolution models, reviewing and clarifying the correct use of the observed abundance ratios in several astrophysical contests. In particular, we start from the well known fact that abundance ratios depend on stellar yields, initial mass function and stellar lifetimes and we s...

The spectral region around the lambda4172 A resonance line of gallium has been synthesized at disk positions mu = 1.0, 0.5, and 0.3. The center-limb variation can be reproduced by Elste's semiempirical model if a macroturbulent smearing of the emergent spectrum due to mass motions with mean velocity decreasing with altitude are introduced. The abundance of Ga derived from disk position mu = 1 i...

We consider the set PHω(M) of volume preserving partially hyperbolic diffeomorphisms on a compact manifold having 1-dimensional center bundle. We show that the volume measure is ergodic, and even Bernoulli, for any C2 diffeomorphism in an open and dense subset of PHω(M). This solves a conjecture of Pugh and Shub, in this setting. Mathematics Subject Classification (2000). 37D30.

Fisheries scientists face a challenge in that virtually all methods of fish capture or observation are selective. Further, most fish capture methods can be applied to only a fraction of the entire area of interest. Thus, measures such as catch per unit effort (C/f) or catch per area can only be regarded, at best, as being proportional to the true population abundance (see Chapter 7). The method...

We construct an abundance of Hilbertian domains: Let O be a countable separably Hilbertian domain with a qoutient eld K and let e 2 be an integer. Let L be an abelian extension of K such that ford(a) j a 2 G(L=K)g is unbounded, and let O L be the integral closure of O in L. Then, for almost all 2 G(K) e , each ring between O L and L K s () is separably Hilbertian.

There is a practically unlimited amount of natural language data available. Still, recent work in text comprehension has focused on datasets which are small relative to current computing possibilities. This article is making a case for the community to move to larger data and is offering the BookTest dataset as a step in that direction.

the morphological diversity of arbuscular mycorrhizal fungi (amf) at the anguran zn and pb mining region (zanjan province, iran) were studied along a transect from the mine to 4500 m away. within each plot, a composite sample of root and rhizospheric soil from a dominant indigenous plant was collected. the soil samples were analyzed for their physico-chemical characteristics. spores were extrac...

encouraging natural enemies by growing attractive plants is considered an effective method of pest control in organic farming. however, it is important to identify which flowers best attract beneficial insects. in this study, relative attractiveness of 16 species of flowering plants to adult hoverflies was assessed by conducting timed observations of feeding-visit frequencies. the experiments w...