The composition of phosphate granules in the digestive glands of marine prosobranch gastropods: variation in relation to taxonomy

The composition of some 1150 phosphate granules in the digestive glands of over 40 species of marine prosobranch gastropods has been surveyed using a simple preparation technique and semiquantitative SEM x-ray microanalysis. Spectral peaks for Mg, K, Ca, Mn, Fe and Zn were compared to that of P. Four major types of phosphate granule can be recognised, each generally characteristic of a taxonomic grouping: high Mg in archaeogastropods and littorinids, multiple metal in higher mesogastropods, and, in neogastropods, Mg-Ca in muricoideans and high Zn in buccinoideans. At least one Conus species (C. ventricosus) has high-Mg granules. Some causes of variation in granule composition are discussed: speculatively, it is suggested a palaeoenvironmental influence seems possible.info:eu-repo/semantics/publishedVersio

Information-theoretic determination of ponderomotive forces

From the equilibrium condition $\delta S=0$ applied to an isolated thermodynamic system of electrically charged particles and the fundamental equation of thermodynamics ($dU = T dS-(\mathbf{f}\cdot d\mathbf{r})$) subject to a new procedure, it is obtained the Lorentz's force together with non-inertial terms of mechanical nature. Other well known ponderomotive forces, like the Stern-Gerlach's force and a force term related to the Einstein-de Haas's effect are also obtained. In addition, a new force term appears, possibly related to a change in weight when a system of charged particles is accelerated.Comment: 10 page

Spiral diffusion of rotating self-propellers with stochastic perturbation

Translationally diffusive behavior arising from the combination of orientational diffusion and powered motion at microscopic scales is a known phenomenon, but the peculiarities of the evolution of expected position conditioned on initial position and orientation have been neglected. A theory is given of the spiral motion of the mean trajectory depending upon propulsion speed, angular velocity, orientational diffusion and rate of random chirality reversal. We demonstrate the experimental accessibility of this effect using both tadpole-like and Janus sphere dimer rotating motors. Sensitivity of the mean trajectory to the kinematic parameters suggest that it may be a useful way to determine those parameters

Pedagogies of inclusion: a critical exploration of small-group teaching practice in higher education

This paper provides a critical examination of inclusion as a pedagogic principle through a practice-based interrogation of contemporary ‘good practice’ strategies for encouraging inclusion in small-group teaching. It reflects on our experiences of delivering four classroom exercises that are frequently proposed as strategies for increasing inclusion, and borrows insight from critical intersectional feminist pedagogy to interrogate normative discourses of inclusion in HE. We argue that both the terms of inclusion, and the assumption that (verbal) participation is itself a measure of improving inclusion in classroom spaces, require interrogation. This article thus responds to the proliferation of inclusion discourses in contemporary UK HE, by identifying some of the potential pitfalls of measuring inclusion through the limited scope of participatio

Generalized Phase Rules

For a multi-component system, general formulas are derived for the dimension of a coexisting region in the phase diagram in various state spaces.Comment: In the revised manuscript, physical meanings of D's are explained by adding three figures. 10 pages, 3 figure

Pulping characteristics of Pinus caribaea from Fiji: The effect of rate of growth

Samples of Pinus caribaea Mor. var hondurensis Barr. and Golf. from Drasa and Seaqaqa in Fiji were sub-divided so that they represented the fastest and slowest growth rate on each site. It was found that the fast growing trees yielded approximately twice the volume of wood yielded by the slow growing trees. There were no significant differences in apparent wood density or chemical composition, in pulp yield or ease of digestion by the sulphate process or in the characteristics of the unbleached pulp. In the absence of better information on which to base a selection programme, the limited evidence of this trial indicates that the best policy for the forester producing pulp wood is to adopt methods and to make selections to obtain high volume production

Pulping characteristics of Dicymbe altsoni from Guyana

A sample consisting of one tree of Dicymbe altsoni from Guyana was examined to determine its pulping characteristics. This sample was not large enough to produce definitive results, but it was considered that an indication could be obtained. Bark content, wood density, chemical analyses and fibre dimensions are reported. Sulphate cooks yielded 48.1% 9f screened pulp with a kappa number of 33.1 to 44.3% of pulp with a kappa number of 22.9. Bleaching trials by a four-stage sequence, using successive applications of chlorine, sodium hydroxide, sodium hypochlorite and chlorine dioxide, produced pulp with a brightness of 83% (absolute scale). It is believed that if D. altsoni was mixed with the six Guyanan species examined earlier, it would not make any major difference to the quantity or quality of the pulp

Pulping characteristics of three trees of Pinus caribaea with different densities grown in Jamaica

The pulping characteristics of three trees of Pinus caribaea var hondurensis with different densities grown in Jamaica were determined using the sulphate method. Ten trees, ten years old, had been selected at random from a single plantation in Jamaica and the first, fifth and ninth in order of density were pulped to assess the differences in pulping characteristics that might be due to density. Two digestions, one with 17.5% active alkali, one with 20% were made on each tree using otherwise identical conditions. At both alkali doses yields of pulp increased with increasing density of the wood and, unexpectedly, the Kappa numbers of the pulps from the medium density wood were higher than those of either of the others. The breaking lengths and bursting strengths decreased and the bulk increased with increasing density. When compared at equal digestion conditions, the tearing strengths increased but to a peak with medium density. This was influenced by the higher Kappa numbers of the pulps from medium density wood and, when compared at equal Kappa numbers, the tearing strength showed a marked increase as the wood density increased from low to medium, and a smaller increase as it increased from medium to high density. The same trends held in the case of bleached pulps. Because of the limited scale of this trial and the fact that the medium density sample yielded pulps with Kappa numbers completely out of line with the pulps from the other two samples, it is not possible to draw firm conclusions about the relationship between density and pulping characteristics, or the merit of density for predicting the quality of pulp. However, in this and in earlier similar work (Tropical Products Institute Report L25) it appears that low density trees can have the economic disadvantage of not only higher handling costs but also lower pulp yields per bone dry ton, and the technical disadvantage of giving the lowest tearing strength although with somewhat higher bonding strengths. The choice between medium and highest density is obscure. The conclusion might be different with trees at a different age and site conditions because both these affect the general level of pulp strength and they also affect the relationship between bonding and tearing strength

Pulping characteristics of Pinus oocarpa grown on Mountain Pine Ridge, Belize

A single sample of Pinus oocarpa from Mountain Pine Ridge, Belize was pulped by the sulphate process. The results of pulping and pulp evaluation, together with chemical analysis of the wood and fibre dimensions are reported. The sample consisted of twenty trees selected at random from a naturally regenerating forest. The average age of the trees was estimated as 30 years with a range of 20 to 46 years. Chemical analysis showed the wood to have an a-cellulose content of 48.9% and a lignin content of 28.7%. The fibres were 3.13 mm long, 49.8 micrometres wide and had walls 6.9 micrometres thick. Pulping by the sulphate process yielded between 38% and 44% of unbleached pulp. These yields were lower than usually found in pines. The pulp had strength characteristics generally similar to those of pulps from Southern Pines of the USA. Compared with pulps obtained from P. caribaea growing in the same area, it was found that P. oocarpa gave lower yields of marginally better pulps

The relationship between cognitive variables and offending behaviour in adults with intellectual disabilities : a systematic review

Background Interventions for offenders with intellectual disabilities (ID) have used cognitive variables as measures of treatment outcome. However, the relevance of cognitive variables to offending in people with intellectual disabilities is unclear. This review aimed to evaluate the evidence for a relationship between cognitive variables and offending in people with intellectual disabilities. Method A systematic search identified studies comparing offenders and non‐offenders with intellectual disabilities on an aspect of cognition. Seven cognitive variables were found and compared across 15 studies. These were appraised for their quality using an adapted quality appraisal checklist. The reliability and validity of cognitive measures were also considered. Results and conclusions Other than for cognitive distortions, the evidence for a relationship between cognitive variables and offending in people with intellectual disabilities is currently limited due to methodological weaknesses and the small number of studies assessing each variable. Clinicians are advised to focus on cognitive distortions until better evidence is available