966 resultados para Aquatic plants management
Resumo:
Two putative promoters from Australian banana streak badnavirus (BSV) isolates were analysed for activity in different plant species. In transient expression systems the My (2105 bp) and Cv (1322 bp) fragments were both shown to have promoter activity in a wide range of plant species including monocots (maize, barley, banana, millet, wheat, sorghum), dicots (tobacco, canola, sunflower, Nicotiana benthamiana, tipu tree), gymnosperm (Pinus radiata) and fern (Nephrolepis cordifolia). Evaluation of the My and Cv promoters in transgenic sugarcane, banana and tobacco plants demonstrated that these promoters could drive high-level expression of either the green fluorescent protein (GFP) or the beta -glucuronidase (GUS) reporter gene (uidA) in vegetative plant cells. In transgenic sugarcane plants harbouring the Cv promoter, GFP expression levels were comparable or higher (up to 1.06% of total soluble leaf protein as GFP) than those of plants containing the maize ubiquitin promoter (up to 0.34% of total soluble leaf protein). GUS activities in transgenic in vitro-grown banana plants containing the My promoter were up to seven-fold stronger in leaf tissue and up to four-fold stronger in root and corm tissue than in plants harbouring the maize ubiquitin promoter. The Cv promoter showed activities that were similar to the maize ubiquitin promoter in in vitro-grown banana plants, but was significantly reduced in larger glasshouse-grown plants. In transgenic in vitro-grown tobacco plants, the My promoter reached activities close to those of the 35S promoter of cauliflower mosaic virus (CaMV), while the Cv promoter was about half as active as the CaMV 35S promoter. The BSV promoters for pregenomic RNA represent useful tools for the high-level expression of foreign genes in transgenic monocots.
Resumo:
The financial and personal burden of chronic cardiac disease is high. Costs are likely to increase over the next few decades. Promising applications of telehealth have appeared in the diagnosis and management of cardiac disease and there are indications that telehealth services can improve the management of chronic cardiac disease as well as extend services to remote and rural populations. Telehealth has been applied to the capture of symptoms of cardiac disease with electrocardiography and echocardiography, to the management and rehabilitation of recently discharged patients, and in peer-to-peer consultation where remote expertise can facilitate diagnosis. Telehealth promises cost reductions in service delivery, although there is a need for properly controlled cost-effectiveness trials to underpin telehealth with a firm evidence base.
Resumo:
Increased nitrogen loading has been implicated in eutrophication occurrences worldwide. Much of this loading is attributable to the growing human population along the world's coastlines. A significant component of this nitrogen input is from sewage effluent, and delineation of the distribution and biological impact of sewage-derived nitrogen is becoming increasingly important. Here, we show a technique that identifies the source, extent and fate of biologically available sewage nitrogen in coastal marine ecosystem. This method is based on the uptake of sewage nitrogen by marine plants and subsequent analysis of the sewage signature (elevated delta N-15) in plant tissues. Spatial analysis is used to create maps of delta N-15 and establish coefficient of variation estimates of the mapped values. We show elevated delta N-15 levels in marine plants near sewage outfalls in Moreton Bay, Australia, a semi-enclosed bay receiving multiple sewage inputs. These maps of sewage nitrogen distribution are being used to direct nutrient reduction strategies in the region and will assist in monitoring the effectiveness of environmental protection measures. (C) 2001 Elsevier Science Ltd. All rights reserved.
Resumo:
We conducted a randomised, controlled field trial during 1998/1999 to evaluate the hypothesis that improved piglet management would improve the reproductive performance of smallholder sows. Simple changes were introduced into the treatment herds including the construction of a heated piglet-separation pen, vitamin injections, creep feeding and early weaning. The control herds were unchanged. Data were collected from all sows in each enrolled herd over two farrowings. We enrolled 176 sows, including 170 (96 treatment and 74 control) sows that remained throughout the study period. Significant differences in the reproductive performance of treatment and control sows were recorded for interfarrowing interval (median 176 versus 220 days), average number liveborn over 2 litters (11 versus 12), and average preweaning mortality over 2 litters (0 versus 37%). Based on a discount rate of 17%, the benefit-cost ratio of the treatment was 11.1 and 12.1 over 3 and 5 years, respectively. (C) 2001 Elsevier Science B.V. All rights reserved.
Resumo:
Mesenchymal hamartomas of the chest wall are rare benign lesions usually discovered in infancy. The authors present their experience with 3 cases. All of these cases were managed initially conservatively, although 1 child required a thoracotomy and partial tumour resection at 5 months of age because of respiratory compromise. The other 2 children have now reached 5 and 6 years of age with the tumors becoming less prominent. The authors believe many cases can be managed conservatively because malignant change has not been reported, and the lesions often become relatively smaller as the child grows. J Pediatr Surg 36:1346-1349, Copyright (C) 2001 by W.B. Saunders Company.
Resumo:
Nest use, home-range characteristics and nightly movements by the northern bettong (Bettongia tropica) were examined before and after a low- to moderate-intensity fire in sclerophyll woodland in north-eastern Australia using radio-telemetry. In all, 23 animals were radio-tracked at three-month intervals between February 1995 and May 1996. During November 1995 a low- intensity experimental fire burned the entire home range of most animals. The northern bettong appeared fairly catholic in choice of nest site, with a variety of nest locations and nesting materials used. Prior to the fire, nests were generally located in areas of dense cover, such as the skirts of grass trees (46%) or grass close to a log (29%). After fire removed most ground cover in the nesting areas of most animals, bettongs used remaining shelter such as boulder piles (45%), recently fallen trees (8%) and patches of unburnt vegetation (21%). Nest areas (10.1 ha) of males were significantly larger than those of females (5.4 ha). Home ranges of both sexes were large (59 ha) and most ranges lacked distinct core areas, suggesting that bettongs used all parts of their home ranges equally. High mean rates of nightly movement by the northern bettong indicated that large distances were moved within home ranges during nightly foraging. No significant fire-related changes were detected in home-range size, home-range location, nest-area location or mean rates of nightly movement, suggesting that the northern bettong is well adapted to the low- and medium-intensity fires that characterise its habitat.