Compound equation developed for postnatal growth of birds and mammals

Compound growth equation was developed in which the rate of this linear growth process is regarded as proportional to the mass already attained at any instant by an underlying Gompertz process. This compound growth model was fitted to the growth data of a variety of birds and mammals of both sexes

ENVIRONMENTAL POLICY ISSUES: CHAOS AND CONFUSION

Environmental Economics and Policy,

The industrial processing of unidirectional fiber prepregs

Progress made in the industrial processing of preimpregnated composites with unidirectional fibers is discussed, with particular emphasis on applications within the aerospace industry. Selection of industrial materials is considered. Attention is given to the conditions justifying the use of composites and the properties required of industrial prepregs. The hardening cycle is examined for the cases of nonmodified and polymer modified resins, with attention given to the stabilization of flow, the necessary changes of state, viscosity control, and the elimination of porosity. The tooling necessary for the fabrication of a laminated plate is illustrated, and the influence of fabrication and prepreg properties on the mechanical characteristics of a laminate are indicated. Finally, the types of prepregs available and the processing procedures necessary for them are summarized

Parent-child relationships and dyadic friendship experiences as predictors of behavior problems in early adolescence

This study focused on support and conflict in parent–child relationships and dyadic friendships as predictors of behavior problems in early adolescence (n¼182; M age¼12.9 years, 51% female, 45% African American, 74% two-parent homes). Support and conflict in one relationship context were hypothesized to moderate the effects of experiences in the other relationship context. Adolescent-reported antisocial behavior was low when either parent–child relationships or friendships were low in conflict, and adolescent-reported depressed mood was low when either friendship conflict was low or parental support was high. Parent-reported antisocial behavior was high when high levels of conflict were reported in either parent–child or friendship relationships and adolescent-reported depressed mood was high when either parental or friendship support was low. Associations appear to be similar for boys and girls as no interactions involving gender were significant.

Aid for Trade: Cool Aid or Kool-Aid?

Aid for Trade may alleviate some fears by developing countries about the social cost of trade reforms and hence help de-block the WTO negotiations. It may also help address critical supply-side issues and contribute to the achievement of the MDGs. However, there is wide divergence in views what is covered, what should be supported and how. There are concerns among developing countries that, despite promises, aid for trade may simply be a redistribution of existing funds, that it may not address development priorities, and that arduous, new conditions will be attached. For these reasons, developing countries that might be expected to have welcomed the possibility of aid for trade, have looked with some suspicion at the proposals, regarding aid for trade more as Kool-Aid, rather than cool aid!

Direct calculation of the crystal-melt interfacial free energies for continuous potentials: Application to the Lennard-Jones system

Extending to continuous potentials a cleaving wall molecular-dynamics simulation method recently developed for the hard-sphere system [Phys.Rev.Lett 85, 4751 (2000)], we calculate the crystal-melt interfacial free energies, $\gamma$, for a Lennard-Jones system as functions of both crystal orientation and temperature. At the triple point, T* = 0.617, the results are consistent with an earlier cleaving potential calculation by Broughton and Gilmer [J. Chem. Phys. {\bf 84}, 5759 (1986)], however, the greater precision of the current calculation allows us to accurately determine the anisotropy of $\gamma$. From our data we find that, at all temperatures studied, $\gamma_{111} < \gamma_{110} < \gamma_{100}$. Comparison is made to the results from our previous hard-sphere calculation and to recent results for Ni by Asta, Hoyt and Karma [Phys. Rev. B, 66 100101(R) (2002)].Comment: 7 pages, 3 figures, 2 table