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Sport is important internationally; but in Australia, it is part of the national identity. The enjoyment of public open space for sport is, therefore, an assumed community right. We interviewed key staff from inner Sydney councils about management issues associated with public open space. The greatest concern was sporting fields – formal and informal – which were considered to have exceeded carrying capacity mainly because of the unintended outcomes of government programmes/policies spanning; (1) ‘healthy lifestyles’ which increased public open space use; (2) ‘urban consolidation’ increased inner-city population density with associated increased usage and loss of open space; (3) ‘temporal water restriction’ during drought (not ‘water budgets’) which intensify management issues; and (4) ‘building the education revolution’, meaning that public open space lost from schools results in increased pressure on public open space. Consequences have increased human pressure on public open space without commensurate consideration for the management and/or expansion of these areas.  相似文献   
2.
The use of different types of phenolic binding agents (PBA) in conjunction with the in vitro gas production technique for the assessment of phenolic related antinutritive factors in browse were compared. During a grazing trial by goats, three fractions, grazed leaves (GL), ungrazed leaves (UL) or stems of ungrazed leaves (US) of Robinia pseudoacacia, together with three harvests of leaves of Cistus incanus and a summer harvest of Fraxinus ornus or Carpinus duinensis were analysed for total extractable phenols (TEPH), total extractable tannins (TETa), condensed tannins (vanillin–HCl) (TECTa) and extractable and total proanthocyanidins (TEPAs and TOPAs). Gas production from the samples with or without adding insoluble polyvinylpolypyrrolidone (IPVP), soluble PVP or polyethylene glycol of different molecular weights was measured. The kinetics of gas production were determined using the equation p=a+b (1-ect). The effects of addition of the PBAs were assessed as percentage changes in the rate and volume of gas production or concentration of volatile fatty acids (VFA). Levels (mg g−1 DM) of TEPH varied from 4·9 to 100·4, TETa from 0·6 to 58·0, TECTa from 1·0 to 64·6, and TEPas or TOPAs from 5·7 to 283·0 and from 12·4 to 331·4. Except for PVP360 which depressed fermentation, addition of 200–500 mg of the other PBAs to rumen liquor/buffer or a tannin free hay, did not affect (P>0·05) fermentation. The highest increase in gas production was achieved with PEG4, PEG8 and PEG10 followed by PVP10, PVP40 and IPVP after 12–24 h incubation. The percentage increase in gas production as a result of adding the PEGs was best associated (r=0·83–0·96; P<0·01) with the higher concentrations of total VFAs after 96 h incubation and was also best related (r=0·89–0·91; P<0.01) to the levels of extractable condensed tannins (TECTa and TEPAs) in the browse. It was concluded that PEGs were more effective than PVPs in eliminating phenolic related antinutritive factors and would be preferred for use in conjunction with the gas technique for the assessment of phenolic related antinutritive factors in feeds.  相似文献   
3.
Bovine postpartum uterine disease, metritis, affects about 40% of animals and is widely considered to have a bacterial aetiology. Although the gamma-herpesvirus bovine herpesvirus 4 (BoHV-4) has been isolated from several outbreaks of metritis or abortion, the role of viruses in endometrial pathology and the mechanisms of viral infection of uterine cells are often ignored. The objectives of the present study were to explore the interaction, tropism and outcomes of BoHV-4 challenge of endometrial stromal and epithelial cells. Endometrial stromal and epithelial cells were purified and infected with a recombinant BoHV-4 carrying an enhanced green fluorescent protein (EGFP) expression cassette to monitor the establishment of infection. BoHV-4 efficiently infected both stromal and epithelial cells, causing a strong non-apoptotic cytopathic effect, associated with robust viral replication. The crucial step for the BoHV-4 endometriotropism appeared to be after viral entry as there was enhanced transactivation of the BoHV-4 immediate early 2 gene promoter following transient transfection into the endometrial cells. Infection with BoHV-4 increased cyclooxygenase 2 protein expression and prostaglandin estradiol secretion in endometrial stromal cells, but not epithelial cells. Bovine macrophages are persistently infected with BoHV-4, and co-culture with endometrial stromal cells reactivated BoHV-4 replication in the persistently infected macrophages, suggesting a symbiotic relationship between the cells and virus. In conclusion, the present study provides evidence of cellular and molecular mechanisms, supporting the concept that BoHV-4 is a pathogen associated with uterine disease.  相似文献   
4.
This work reports a microstructural analysis of S-rich CuIn(S,Se)2 layers produced by electrodeposition of CuInSe2 precursors followed by annealing at 500 °C under sulphurising conditions, as function of the annealing time (tann). The characterisation of the layers by Raman scattering (RS) and Scanning Electron Microscopy (SEM) techniques has allowed to observe a strong dependence of the layer microstructure and the secondary phases synthesised during the sulphurising step on the annealing parameters. The experimental data show the existence of two distinct regimes: For tann < 20 min, increasing tann leads to a significant improvement of the crystalline quality of the absorbers. For longer annealing times, the changes observed in the frequency of the main CuIn(S,Se)2 A1 mode in the Raman spectra have been attributed to a higher incorporation of S in the chalcopyrite lattice. The characterisation of devices fabricated with these absorbers has allowed to analyse the impact of the microstructural features on the parameters of the solar cells, observing the existence of a strong correlation between the solar cell parameters and the spectral features of the main Raman mode.  相似文献   
5.
Chalcopyrite thin film solar cells by electrodeposition   总被引:3,自引:0,他引:3  
This paper reviews the state of the art in using electrodeposition to prepare chalcopyrite absorber layers in thin film solar cells. Most of the studies deal with the direct preparation of Cu(In,Ga)Se2 films, and show that the introduction of gallium in the films is now becoming possible from single bath containing all the elements. Electrodeposition can also be used to form precursor films with stacked layer structures, of pure elements or of combinations with binary or even ternary films. Thermal annealing treatments are of dramatic importance to provide suitable electronic quality to the layers. They are often done in the presence of a chalcogen (selenium or sulfur) over pressure and there is a tendency to use rapid thermal processes. Less studies are devoted to complete solar cell formation. Significant progresses have been made in the recent period with several groups achieving cell efficiencies around 8–10% on different substrates. A record efficiency of 11.3% is reported for a cell with an absorber presenting a band gap of 1.47 eV. First results on the manufacturability of the corresponding process to large areas are presented.  相似文献   
6.
The objective of this study was to characterise the volatile organic compounds (VOCs) profile of plant species, bulk forage grazed by sheep and produced milk at different mountainous areas of Greece. The most abundant plant species of vegetation at 800 m (hill‐land) and 1300 m (highland) altitude, bulk forage and milk samples, were collected. The VOCs profiles of the plant species and milk varied. Common VOCs in milk from both areas were identified, whereas others were discriminatory for each area. Overall, the VOCs composition of mountainous milk could provide a basis for Feta cheese identification with its region.  相似文献   
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