Curriculum for the middle school

A book review of A Curriculum for the Middle School Years, by John H. Lounsbury and Gordon E. Vars

Promoting Moral Growth: From Piaget to Kohlberg

A review of Promoting Moral Growth: From Piaget to Kohlberg by Richard H. Hersh, Diana P. Paolitto and Joseph Reimer

Mathematical modelling of tissue-engineering angiogenesis

We present a mathematical model for the vascularisation of a porous scaffold following implantation in vivo. The model is given as a set of coupled non-linear ordinary differential equations (ODEs) which describe the evolution in time of the amounts of the different tissue constituents inside the scaffold. Bifurcation analyses reveal how the extent of scaffold vascularisation changes as a function of the parameter values. For example, it is shown how the loss of seeded cells arising from slow infiltration of vascular tissue can be overcome using a prevascularisation strategy consisting of seeding the scaffold with vascular cells. Using certain assumptions it is shown how the system can be simplified to one which is partially tractable and for which some analysis is given. Limited comparison is also given of the model solutions with experimental data from the chick chorioallantoic membrane (CAM) assay

Research Notes: Agriculture Canada

Nine flavonol glycosides occur in various soybean cultivars with gene t1 resulting in kaempferol and T1 controlling the presence of quercetin plus kaempferol (Buttery and Buzzell, 1973). The sugars of these glycosides have been identified and four flavonol glycoside genes have been studied (Buzzell and Buttery, 1973, and unpublished). A monoglucoside is the basic glycoside; it is present even when the four genes are recessive

Searching for Clusters of Galaxies with SUMSS

Statistical overdensities of radio sources in the NRAO VLA Sky Survey (NVSS) catalogue have proven to be signposts to high-redshift clusters of galaxies. A similar search for overdensities has been carried out in the Sydney University Molonglo Sky Survey (SUMSS), which is closely matched in resolution and frequency to the NVSS. Sixty potential southern-hemisphere clusters have been found in SUMSS

Power requirements for electron cyclotron current drive and ion cyclotron resonance heating for sawtooth control in ITER

13MW of electron cyclotron current drive (ECCD) power deposited inside the q = 1 surface is likely to reduce the sawtooth period in ITER baseline scenario below the level empirically predicted to trigger neo-classical tearing modes (NTMs). However, since the ECCD control scheme is solely predicated upon changing the local magnetic shear, it is prudent to plan to use a complementary scheme which directly decreases the potential energy of the kink mode in order to reduce the sawtooth period. In the event that the natural sawtooth period is longer than expected, due to enhanced alpha particle stabilisation for instance, this ancillary sawtooth control can be provided from > 10MW of ion cyclotron resonance heating (ICRH) power with a resonance just inside the q = 1 surface. Both ECCD and ICRH control schemes would benefit greatly from active feedback of the deposition with respect to the rational surface. If the q = 1 surface can be maintained closer to the magnetic axis, the efficacy of ECCD and ICRH schemes significantly increases, the negative effect on the fusion gain is reduced, and off-axis negative-ion neutral beam injection (NNBI) can also be considered for sawtooth control. Consequently, schemes to reduce the q = 1 radius are highly desirable, such as early heating to delay the current penetration and, of course, active sawtooth destabilisation to mediate small frequent sawteeth and retain a small q = 1 radius.Comment: 29 pages, 16 figure

P3_9 Scooby and Shaggy: Metabolic Miracles

In the cartoon `What's New Scooby-Doo?' the characters Shaggy and Scooby are seen to eat large volumesof food without gaining any weight. Their effective temperatures in order to radiate away the excess energywere calculated to be T_Sh ~ 97 ± 033 °C for Shaggy, and T_Sc ~ 140 ± 43 °C for Scooby. It was concludedthat under normal circumstances, the subjects would perish of extreme hyperthermia. It was also notedthat Shaggy could survive if he was able to sweat continuously at the maximum rate for a human

P3_1 On the feasibility of neutrino sails

In this paper we consider whether a neutrino sail, a sheet of material absorbing neutrinos and gaining thrust from their momentum change, is a viable method of spacecraft propulsion. We calculate the thrust that could be achieved per unit area and compare this to that possible using a photon solar sail. We also calculate the thickness of sail necessary assuming that there are no special conditions under which the cross section for neutrino interactions with nuclei can be increased. We find that a thickness of 34000 light years would be necessary if a sheet of osmium were used, whereas neutron star matter could achieve this at 189 km thickness. We conclude that a neutrino sail is not a practical method of propulsion