Influence of fungal pathogens and environmental conditions on disease severity, flower fall and desiccation of harvested Geraldton waxflower - 2. Studies with commercial packages

Relationships were examined between environmental conditions mediated by packaging and handling and the deterioration of harvested Geraldton waxflower cv. 'Fortune Cookie'. Disease severity plus flower and leaf drop caused by inoculation with Botrytis cinerea were reduced by lowering handling temperatures to 0, 5 or 5/20 degreesC alternated daily, versus 20 degreesC. They were also reduced by inhibition of ethylene action with a silver thiosulfate pulse pretreatment. Additionally, treatments that enhanced water loss, such as packing dry, keeping forced air-cooling holes open and strategic placement of extra ventilation holes may also reduce disease severity and flower plus leaf fall. Inclusion of KMnO4-based Bloomfresh ethylene scrubbing sachets in packages did not reduce disease severity or lessen flower plus leaf fall. Thus, deterioration of waxflower packaged in commercial cartons can be minimised by keeping temperatures low, packing plant material dry, use of cartons with strategically placed ventilation holes and/or pretreatment with silver thiosulfate.

Habitat requirements for the conservation of arboreal marsupials in dry sclerophyll forests of Southeast Queensland, Australia

The habitat requirements of arboreal marsupials were investigated in the dry sclerophyll forests of southeast Queensland, Australia. Species richness and abundance of arboreal marsupials was correlated to the proportion of total stand basal area occupied by lemon-scented gum (Corymbia citriodora), the height of the tallest trees, and density of hollow-bearing trees. The first two factors suggested that the most productive forests were also the most suitable habitats for arboreal marsupials. Importantly, the number of hollow-bearing trees was a significant factor in determining species richness and abundance of arboreal marsupials in this study, with the maximum number of species reached at sites containing greater than or equal to4 hollow-bearing trees/ha, and maximum abundance occurring at sites with :6 hollow-bearingtrees/ha. The proportion of C. citriodora was significant for the presence of the common brushtail possum (Trichosurus vulpecula), greater glider (Petauroides volans), and the yellow-bellied glider (Petaurus australis), while understory Acacia sp. density was important for the presence of the sugar glider (Petaurus breviceps). The yellow-bellied glider was also affected by two other variables: the density of hollow-bearing trees >50 cm diameter at breast height (dbh), and the time since the last logging. Current Codes of Practice regulating the density of hollow-bearing trees and silvicultural practices in state-owned timber production forests appear to provide adequate protection for arboreal marsupials, but the recently introduced increase in timber extraction rates within state forests may be detrimental to the animals. Also, protective prescriptions do not apply to the privately owned and leasehold estates, which contain the majority of the dry sclerophyll forests in southeast Queensland.

Mapping glider habitat in dry eucalypt forests for Montreal Process indicator 1.1: Fragmentation of forest types

Accurate habitat mapping is critical to landscape ecological studies such as required for developing and testing Montreal Process indicator 1.1e, fragmentation of forest types. This task poses a major challenge to remote sensing, especially in mixedspecies, variable-age forests such as dry eucalypt forests of subtropical eastern Australia. In this paper, we apply an innovative approach that uses a small section of one-metre resolution airborne data to calibrate a moderate spatial resolution model (30 m resolution; scale 1:50 000) based on Landsat Thematic Mapper data to estimate canopy structural properties in St Marys State Forest, near Maryborough, south-eastern Queensland. The approach applies an image-processing model that assumes each image pixel is significantly larger than individual tree crowns and gaps to estimate crown-cover percentage, stem density and mean crown diameter. These parameters were classified into three discrete habitat classes to match the ecology of four exudivorous arboreal species (yellowbellied glider Petaurus australis, sugar glider P. breviceps, squirrel glider P. norfolcensis , and feathertail glider Acrobates pygmaeus), and one folivorous arboreal marsupial, the greater glider Petauroides volans. These species were targeted due to the known ecological preference for old trees with hollows, and differences in their home range requirements. The overall mapping accuracy, visually assessed against transects (n = 93) interpreted from a digital orthophoto and validated in the field, was 79% (KHAT statistic = 0.72). The KHAT statistic serves as an indicator of the extent that the percentage correct values of the error matrix are due to ‘true’ agreement verses ‘chance’ agreement. This means that we are able to reliably report on the effect of habitat loss on target species, especially those with a large home range size (e.g. yellow-bellied glider). However, the classified habitat map failed to accurately capture the spatial patterning (e.g. patch size and shape) of stands with a trace or sub-dominance of senescent trees. This outcome makes the reporting of the effects of habitat fragmentation more problematic, especially for species with a small home range size (e.g. feathertail glider). With further model refinement and validation, however, this moderateresolution approach offers an important, cost eff e c t i v e advancement in mapping the age of dry eucalypt forests in the region.

Dry matter production and boron concentrations of vegetative and reproductive tissues of canola and sunflower plants grown in nutrient solution

Canola (Brassica napus L.) and sunflower (Helianthus annuus L.), two important oilseed crops, are sensitive to low boron (B) supply. Symptoms of B deficiency are often more severe during the reproductive stage, but it is not known if this is due to a decreased external B supply with time or an increased sensitivity to low B during this stage. Canola and sunflower were grown for 75 days after transplanting (DAT) in two solution culture experiments using Amberlite (IRA-743) B-specific resin to maintain constant B concentration in solution over the range 0.6 - 53 muM. Initially, the vegetative growth of both crops was good in all treatments. With the onset of the reproductive stage, however, severe B deficiency symptoms developed and growth of canola and sunflower was reduced with less than or equal to 0.9 and less than or equal to 0.7 muM B, respectively. At these concentrations, reproductive parts failed to develop. The critical B concentration (i.e. 90% of maximum shoot dry matter yield) in the youngest opened leaf was 18 mg kg(-1) in canola and 25 mg kg(-1) in sunflower at 75 DAT. The results of this study indicate that the reproductive stage of these two oilseed crops is more sensitive than the vegetative stage to low B supply.

Beneficial effects of air inclusions on the performance of ethylene vinyl acetate (EVA) mouthguard material

Objective: To investigate the impact characteristics of an ethylene vinyl acetate (EVA) mouthguard material with regulated air inclusions, which included various air cell volumes and wall thickness between air cells. In particular, the aim was to identify the magnitude and direction of forces within the impacts. Method: EVA mouthguard material, A mm thick and with and without air inclusions, was impacted with a constant force impact pendulum with an energy of 4.4 J and a velocity of 3 m/s. Transmitted forces through the EVA material were measured using an accelerometer, which also allowed the determination of force direction and magnitude within the impacts. Results: Statistically significant reductions in the transmitted forces were observed with all the air inclusion materials when compared with EVA without air inclusions. Maximum transmitted force through one air inclusion material was reduced by 32%. Force rebound was eliminated in one material, and reduced second force impulses were observed in all the air inclusion materials. Conclusion: The regulated air inclusions improved the impact characteristics of the EVA mouthguard material, the material most commonly used in mouthguards world wide.

Effect of ethylene vinyl acetate (EVA) closed cell foam on transmitted forces in mouthguard material

Objectives: To compare transmitted forces through ethylene vinyl acetate (EVA) mouthguard material and the same EVA material with gas inclusions in the form of a closed cell foam. Method: EVA mouthguard materials with and without foam gas inclusions and 4 mm thick were impacted with a constant force from an impact pendulum. Various porosity levels in the foam materials were produced by 1%, 5%, and 10% by weight foaming agent. The forces transmitted through the EVA after energy absorption by the test materials were measured with a force sensor and compared. Results: Only minor non-significant differences in transmitted forces through the EVA with and without foam were shown. Conclusions: The inclusion of gas in the form of a closed cell foam in 4 mm thick EVA mouthguard materials did not improve the impact performance of the EVA mouthguard material.

A design method for superconducting MRI magnets with ferromagnetic material

The emphasis of this work is on the optimal design of MRI magnets with both superconducting coils and ferromagnetic rings. The work is directed to the automated design of MRI magnet systems containing superconducting wire and both `cold' and `warm' iron. Details of the optimization procedure are given and the results show combined superconducting and iron material MRI magnets with excellent field characteristics. Strong, homogeneous central magnetic fields are produced with little stray or external field leakage. The field calculations are performed using a semi-analytical method for both current coil and iron material sources. Design examples for symmetric, open and asymmetric clinical MRI magnets containing both superconducting coils and ferromagnetic material are presented.

Rapid field calculations for the effect of ferromagnetic material in MRI magnet design

Magnetic resonance imaging (MRI) magnets have very stringent constraints on the homogeneity of the static magnetic field that they generate over desired imaging regions. The magnet system also preferably generates very little stray field external to its structure, so that ease of siting and safety are assured. This work concentrates on deriving, means of rapidly computing the effect of 'cold' and 'warm' ferromagnetic material in or around the superconducting magnet system, so as to facilitate the automated design of hybrid material MR magnets. A complete scheme for the direct calculation of the spherical harmonics of the magnetic field generated by a circular ring of ferromagnetic material is derived under the conditions of arbitrary external magnetizing fields. The magnetic field produced by the superconducting coils in the system is computed using previously developed methods. The final, hybrid algorithm is fast enough for use in large-scale optimization methods. The resultant fields from a practical example of a 4 T, clinical MRI magnet containing both superconducting coils and magnetic material are presented.

Dry matter production and allocation in Eucalyptus cloeziana and Eucalyptus argophloia seedlings in response to soil water deficits

Effects of soil water availability on seedling growth, dry matter production and allocation were determined for Gympie ( humid coastal) and Hungry Hills ( dry inland) provenances of Eucalyptus cloeziana F. Muell. and for E. argophloia Blakely ( dry inland) species. Seven-month-old seedlings were subjected to well-watered (100% field capacity, FC), moderate (70% FC) and severe (50% FC) soil water regimes in a glasshouse environment for 14 wk. There were significant differences in seedling growth, biomass production and allocation patterns between species. E. argophloia produced twice as much biomass at 100% FC, and more than three times as much at 70% and 50% FC than did either E. cloeziana provenance. Although the humid provenance of E. cloeziana had a greater leaf area at 100% FC conditions than did the dry provenance, total biomass production did not differ significantly. Both E. cloeziana provenances were highly sensitive to water deficits. E. argophloia allocated 10% more biomass to roots than did E. cloeziana. Allometric analyses indicated that relative biomass allocation patterns were significantly affected by genotype but not by soil water availability. These results have implications for taxon selection for cultivation in humid and subhumid regions.

The characteristics of six species of living hollow-bearing trees and their importance for arboreal marsupials in the dry sclerophyll forests of southeast Queensland, Australia

Six species of trees located in the dry sclerophyll forests of southeast Queensland were studied to ascertain which was most suitable to be retained as hollow-bearing trees for nesting and denning by arboreal marsupials. Generally for all tree species, the number of entrances to hollows was positively correlated with the diameter at breast height (DBH) and the growth stage, and entrance diameters also increased in trees with a larger DBH. However, there were differences between the species; Corymbia citriodora had few hollows until the individuals were very large while Eucalyptus crebra had low numbers of hollows throughout its entire size range. It was concluded that a mixture of tree species provided a range of hollow sizes and positions that would be suitable for nesting and denning by arboreal marsupials in those forests. There were large differences between tree species in the relationship between tree size and estimated age. Five of the tree species took between 186 and 230 years to begin to produce hollows while E. crebra took up to 324 years. This suggests that tree species other than E. crebra may be the most preferred for retention in areas where hollow-bearing tree densities are lower than the prescribed level. Other data also suggests there are likely to be enough trees in larger size classes that would begin to form hollows within the next 50 years to compensate for an expected loss of hollow-bearing stags during that same period. In terms of forest operation, the retention of six hollow-bearing trees/ha would represent an estimated loss of 7.3-15% wood production. (C) 2003 Elsevier Science B.V. All rights reserved.

Faeces as a source of DNA for molecular studies in a threatened population of great bustards

With recent advances in molecular biology, it is now possible to use the trace amounts of DNA in faeces to non-invasively sample endangered species for genetic studies. A highly vulnerable population of approximately 100 great bustards (Otis tarda) exists in Morocco necessitating the use of non-invasive protocols to study their genetic structure. Here we report a reliable silica-based method to extract DNA from great bustard faeces. We found that successful extraction and amplification correlated strongly with faeces freshness and composition. We could not extract amplifiable DNA from 30% of our samples as they were dry or contained insect material. However 100% of our fresh faecal samples containing no obvious insect material worked, allowing us to assess the levels of genetic variation among 25 individuals using a 542 bp control region sequence. We were able to extract DNA from four out of five other avian species, demonstrating that faeces represents a suitable source of DNA for population genetics studies in a broad range of species.

Caixas receptoras de correspond??ncias confeccionadas com material recicl??vel

Os Correios t??m como miss??o facilitar as rela????es pessoais e empresariais mediante a oferta de servi??os de correios com ??tica, competitividade, lucratividade e responsabilidade social. Fundamentada em objetivos estrat??gicos, como o de obter padr??es de qualidade e produtividade requeridos pelas partes interessadas e aumentar a percep????o da sociedade em rela????o ?? atua????o da ECT como empresa socialmente respons??vel, a Ag??ncia de Conchas/DR/SPI implantou a????o socioambiental e educacional com a comunidade: a instala????o de caixas receptoras de correspond??ncia em suas resid??ncias, utilizando materiais recicl??veis. O projeto proporcionou ganhos significativos para a Ag??ncia e para os mun??cipes na presta????o de um servi??o com maior qualidade e agilidade a partir da melhoria gradativa das condi????es de entrega nos novos bairros atendidos pelo servi??o, al??m da satisfa????o e do reconhecimento da sociedade com a a????o de inclus??o social

Curso de administra????o de material

O material abrange os seguintes t??picos: t??cnicas modernas de administra????o de materiais;estrutura; funcionamento e desenvolvimento do organismo de material da Administra????o P??blica Federal

Mesa-redonda de pesquisa-a????o em gest??o por compet??ncias: material do participante

A Escola Nacional de Administra????o P??blica, ENAP, em parceria com a Canada School of Public Service, CSPS, vem implementando novas metodologias de abordagem de temas importantes para a melhoria da administra????o p??blica. Em 09 de novembro de 2004 foi instalada a primeira Mesa-redonda de Pesquisa-A????o, ferramenta de pesquisa que tem por objetivo reunir profissionais e especialistas para encontrar solu????es para os desafios enfrentados no servi??o p??blico. O resultado dos debates ?? a publica????o de um material que possa ser ??til a servidores e dirigentes no desempenho de tarefas ou na implementa????o de novas ferramentas de trabalho. A ENAP, cumprindo seu papel de auxiliar na difus??o de conhecimentos no setor p??blico federal, pretende realizar novas mesas periodicamente.