The poverty trap with high fertility rates

The aim of this paper is to clarify the causes of the poverty trap resulting from a negative correlation between income and fertility, in a manner that is consistent with the data across and within countries. This paper points out that a higher fertility rate is the cause of the poverty trap, because of its educational cost aspect.educational cost

Higher homotopy commutativity and cohomology of finite H-spaces

We study connected mod p finite A_p-spaces admitting AC_n-space structures with n<p for an odd prime p. Our result shows that if n is greator than (p-1)/2, then the mod p Steenrod algebra acts on the mod p cohomology of such a space in a systematic way. Moreover, we consider A_p-spaces which are mod p homotopy equivalent to product spaces of odd dimensional spheres. Then we determine the largest integer n for which such a space admits an AC_n-space structure compatible with the A_p-space structure.Comment: This is the version published by Geometry & Topology Monographs on 29 January 200

Differences in the escape response of a grapsid crab in the field and in the laboratory

Escape behaviours of prey animals are frequently used to study the neural control of behaviour. Escape responses are robust, fast, and can be reliably evoked under both field and laboratory conditions. Many escape responses are not as simple as previously suggested, however, and are often modulated by a range of contextual factors. To date it has been unclear to what extent behaviours studied in controlled laboratory experiments are actually representative of the behaviours that occur under more natural conditions. Here we have used the model species, Neohelice granulata, a grapsid crab, to show that there are significant differences between the crabs' escape responses in the field compared to those previously documented in laboratory experiments. These differences are consistent with contextual adjustments such as the availability of a refuge and have clear consequences for understanding the crabs' neural control of behaviour. Furthermore, the methodology used in this study mirrors the methodology previously used in fiddler crab research, allowing us to show that the previously documented differences in escape responses between these grapsid species are real and substantial. Neohelice's responses are delayed and more controlled. Overall, the results highlight the adaptability and flexibility of escape behaviours and provide further evidence that the neural control of behaviour needs to be address in both the laboratory and field context.Fil: Hemmi, J. M.. University of Western Australia; AustraliaFil: Tomsic, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentin

A nonexterior Hopf algebra and loop spaces

AbstractLet A be the Hopf algebra over Zp for a prime p given by A = Λ(xi, yi ¦ 0 ⩽ i ⩽ p − 2) ⊗ (Zp[z](zp)) (deg xi = 2(p + 1)i + 3, deg yi = 2(p + 1)(i + 1) − 1, deg z = 2(p + 1)). Kane showed that A is a minimum candidate for the mod p cohomology of a simply connected mod p finite loop space with p-torsion. In fact, if p = 2, 3, 5, then for X = G2, F4, E8, we have H∗(X; Zp) ≅ A. We prove that if p ⩾ 7, then there are no such loop spaces X

フクラガエル属におけるmtDNAの分子進化 : 脊椎動物で2番目に巨大なミトコンドリアゲノムの発見とその発生要因

広島大学(Hiroshima University)博士(理学)Doctor of Sciencedoctora