Multiple shoot formation in lentil (Lens culinaris) seeds

A protocol based on seed culture was developed for efficient in vitro propagation of lentil (Lens culinaris Medik). Benzyladenine (BA), thidiazuron (TDZ), and kinetin all induced multiple shoot formation. In terms of the number of long shoots (>2.0 cm) produced per seed, BA and TDZ at optimum concentrations (0.2-0.4 and 0.1 mg/litre, respectively) had similar efficiency, whereas kinetin produced less shoots. Murashige and Skoog (MS) salt composition was better than that of Gamborge (B5) for shoot induction. Increasing calcium (Ca) concentration was necessary to overcome shoot-tip necrosis. For shoot elongation, fresh medium of the same composition of shoot induction medium could be used for stumps from medium with low BA (

Identification of a digalactosyl ononitol from seeds of adzuki bean (Vigna angularis)

A digalactosyl ononitol was isolated from seeds of adzuki bean (Vigna angularis [Willd.] Ohwi et Ohasi). Analysis of hydrolysis products and NMR spectroscopy established its structure as O-alpha-D-galactopyranosyl-(1-->6)-O-alpha-D-galactopyranosyl-(1-->3)-O-methyl- D-myo-inositol. (C) 2003 Elsevier Ltd. All rights reserved.

Using the tax system to collect fines

In this article we consider the possibility that fines could be collected through the tax and social welfare systems in the same way as higher education contributions and child support payments are currently administered. We argue that the existing system of fine collection and enforcement leads to high default rates and reduces the usefulness of fines as a sanction. We consider a range of models for the implementation of an income-related fine collection system, and discuss their possible implications for issues including judicial independence, the time taken to repay fines and aggregate fine revenue.

The seeds of lotus japonicus lines transformed with sense, antisense, and sense/antisense galactomannan galactosyltransferase constructs have structually altered galactomannan in their endosperm cell walls

Galactomannan biosynthesis in legume seed endosperms involves two Golgi membrane-bound glycosyltransferases, mannan synthase and galactomannan galactosyltransferase (GMGT). GMGT specificity is an important factor regulating the distribution and amount of (1-->6)-alpha-galactose (Gal) substitution of the (1-->4)-beta-linked mannan backbone. The model legume Lotus japonicus is shown now to have endospermic seeds with endosperm cell walls that contain a high-Gal galactomannan (mannose [Man]/Gal = 1.2-1.3). Galactomannan biosynthesis in developing L. japonicus endosperms has been mapped, and a cDNA encoding a functional GMGT has been obtained from L. japonicus endosperms during galactomannan deposition. L. japonicus has been transformed with sense, antisense, and sense/antisense ("hairpin loop") constructs of the GMGT cDNA. Some of the sense, antisense, and sense/antisense transgenic lines exhibited galactomannans with altered (higher) Man/Gal values in their (T-1 generation) seeds, at frequencies that were consistent with posttranscriptional silencing of GMGT. For T-1 generation individuals, transgene inheritance was correlated with galactomannan composition and amount in the endosperm. All the azygous individuals had unchanged galactomannans, whereas those that had inherited a GMGT transgene exhibited a range of Man/Gal values, up to about 6 in some lines. For Man/Gal values up to 4, the results were consistent with lowered Gal substitution of a constant amount of mannan backbone. Further lowering of Gal substitution was accompanied by a slight decrease in the amount of mannan backbone. Microsomal membranes prepared from the developing T-2 generation endosperms of transgenic lines showed reduced GMGT activity relative to mannan synthase. The results demonstrate structural modification of a plant cell wall polysaccharide by designed regulation of a Golgi-bound glycosyltransferase.

Can we learn more from fewer seeds?

The vital role that 'design of experiment' (DOE) plays when investigating dormancy, germination and potentially influential factors is discussed. The Taguchi analysis, developed by Dr. Genichi Taguchi, is a special application and analysis of the fractional factorial aimed at achieving maximum information from minimum effort and resources.

From Midden to Sieve: The Impact of Differential Recovery and Quantification Techniques on Interpretations of Shellfish Remains in Australian Coastal Archaeology

Experimental mechanical sieving methods are applied to samples of shellfish remains from three sites in southeast Queensland, Seven Mile Creek Mound, Sandstone Point and One-Tree, to test the efficacy of various recovery and quantification procedures commonly applied to shellfish assemblages in Australia. There has been considerable debate regarding the most appropriate sieve sizes and quantification methods that should be applied in the recovery of vertebrate faunal remains. Few studies, however, have addressed the impact of recovery and quantification methods on the interpretation of invertebrates, specifically shellfish remains. In this study, five shellfish taxa representing four bivalves (Anadara trapezia, Trichomya hirsutus, Saccostrea glomerata, Donax deltoides) and one gastropod (Pyrazus ebeninus) common in eastern Australian midden assemblages are sieved through 10mm, 6.3mm and 3.15mm mesh. Results are quantified using MNI, NISP and weight. Analyses indicate that different structural properties and pre- and postdepositional factors affect recovery rates. Fragile taxa (T. hirsutus) or those with foliated structure (S. glomerata) tend to be overrepresented by NISP measures in smaller sieve fractions, while more robust taxa (A. trapezia and P. ebeninus) tend to be overrepresented by weight measures. Results demonstrate that for all quantification methods tested a 3mm sieve should be used on all sites to allow for regional comparability and to effectively collect all available information about the shellfish remains.

Rich task implementation: modernism meets postmodernism

School renewal', 'productive pedagogies', 'rich tasks', 'New Basics', 'key learning areas'--these are some of the discourses of change in selected Queensland schools. This paper will report on teaching as an insider/outsider in a school's Health and Physical Education department during a time of intense pressure for structural, curriculum and pedagogical shifts. As a teacher/researcher, I spent ten weeks in a government secondary school attempting to implement rich tasks as well as collect data using formal and informal interviews, field note, and document analyses, with a focus upon teachers', students' and administrators' sense of change processes and outcomes. It is suggested that the processes of, and barriers to, curriculum change in this context are best explained in terms of tensions between modernist and postmodernist phenomena.

An improved seeded region growing algorithm

Recently Adams and Bischof (1994) proposed a novel region growing algorithm for segmenting intensity images. The inputs to the algorithm are the intensity image and a set of seeds - individual points or connected components - that identify the individual regions to be segmented. The algorithm grows these seed regions until all of the image pixels have been assimilated. Unfortunately the algorithm is inherently dependent on the order of pixel processing. This means, for example, that raster order processing and anti-raster order processing do not, in general, lead to the same tessellation. In this paper we propose an improved seeded region growing algorithm that retains the advantages of the Adams and Bischof algorithm fast execution, robust segmentation, and no tuning parameters - but is pixel order independent. (C) 1997 Elsevier Science B.V.

Desiccation tolerance of three moss species from continental Antarctica

Tolerance of desiccation was examined in three species of moss, Grimmia antarctici Card., Ceratodon purpureus (Hedw.) Brid. and Bryum pseudotriquetrum (Hedw.) Gaertn., Meyer et Scherb. collected from two sites of contrasting water availability in the Windmill Islands, continental Antarctica. Physiological tolerance to desiccation was measured using chlorophyll fluorescence in plugs of moss during natural drying in the laboratory. Differences in relative water content, rate of drying and the response of photosynthesis to desiccation were observed among the three species and between sites. Of the three species studied, G. antarctici showed the lowest capacity to sustain photosynthetic processes during desiccation, B. pseudotriquetrum had an intermediate response and showed the greatest plasticity and C. purpureus showed the greatest capacity to sustain photosynthesis during desiccation. These results fit well with the known distribution of the three species with G. antarctici being limited to relatively wet sites, C. purpureus being common in the driest sites and B. pseudotriquetrum showing a wide distribution between these two extremes. Levels of soluble carbohydrates were also measured in these samples following desiccation and these indicate the presence of stachyose, an oligosaccharide known to be important in desiccation tolerance in seeds, in B. pseudotriquetrum. Both gross morphology and carbohydrate content are likely to contribute to differences in desiccation tolerance of the moss species. These results indicate that if the Casey region continues to dry out, as a result of local geological uplifting or global climate change, we would expect to see not only reductions in the moss community but also changes in community composition. G. antarctici is likely to become more limited in distribution as C. purpureus and B. pseudotriquetrum expand into drying areas.