979 resultados para Leak locations


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Batches of glasshouse-grown flowering sorghum plants were placed in circular plots for 24 h at two field sites in southeast Queensland, Australia on 38 occasions in 2003 and 2004, to trap aerial inoculum of Claviceps africana. Plants were located 20-200 m from the centre of the plots. Batches of sorghum plants with secondary conidia of C. africana on inoculated spikelets were placed at the centre of each plot on some dates as a local point source of inoculum. Plants exposed to field inoculum were returned to a glasshouse, incubated at near-100% relative humidity for 48 h and then at ambient relative humidity for another week before counting infected spikelets to estimate pathogen dispersal. Three times as many spikelets became infected when inoculum was present within 200 m of trap plants, but infected spikelets did not decline with increasing distance from local source within the 200 m. Spikelets also became infected on all 10 dates when plants were exposed without a local source of infected plants, indicating that infection can occur from conidia surviving in the atmosphere. In 2005, when trap plants were placed at 14 locations along a 280 km route, infected spikelets diminished with increasing distance from sorghum paddocks and infection was sporadic for distances over 1 km. Multiple regression analysis showed significant influence of moisture related weather variables on inoculum dispersal. Results suggest that sanitation measures can help reduce ergot severity at the local level, but sustainable management will require better understanding of long-distance dispersal of C. africana inoculum.

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A 5' Taq nuclease assay specific for Avibacterium paragallinarum was designed and optimized for use in diagnosing infectious coryza. The region chosen for assay design was one of known specificity for Av. paragallinarum. The assay detected Av. paragallinarum reference strains representing the three Page and the eight Kume serovars, and field isolates from diverse geographical locations. No cross-reactions were observed with other Avibacterium species, with other bacteria taxonomically related to Av. paragallinarum nor with bacteria and viruses likely to be present in swabs collected from suspected infectious coryza cases. The detection limit for the assay was 6 to 60 colony-forming units per reaction. Twenty-two out of 53 swabs collected from sick birds reacted in the 5' Taq nuclease assay, whereas Av. paragallinarum was not isolated from any of the swabs. All of the 22 swabs yielded other bacteria in culture. The presence of Av. paragallinarum in the swabs was also demonstrated by sequencing, thereby confirming the ability of the assay to detect Av. paragallinarum in the presence of other bacteria. The ability to quantify bacterial load in the swabs using the 5' Taq nuclease assay was demonstrated.

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Population substructure and hybridization, among other factors, have the potential to cause erroneous associations in linkage disequilibrium (LD) mapping. Two closely related spotted gum eucalypts, Corymbia variegata and C. henryi (Myrtaceae) occur in sympatry in the east coast of Australia and potentially interbreed. They are morphologically similar but are distinguished as separate species based on capsule and foliage size. To determine whether they hybridize in nature and its implications for LD mapping, we investigated the level of molecular divergence between the two species at two sympatric locations separated by 300 kilometres. Very few individuals of intermediate morphology were identified, despite the two species occurring only metres apart. Analysis of genetic structure using 12 microsatellite loci showed that genetic differentiation between populations of the same species at different locations (FST = 0.07 for both species; p = 0.0001) was significantly higher than that observed between species at each location (mean FST = 0.02 and 0.04 for Cherry tree and Bunyaville respectively; p = 0.0001; all Mann-Whitney U-test p ≤ 0.01). No species-specific alleles or significant allele frequency differences were detected within a site, suggesting recurrent local gene flow between the two species. The lack of significant allele frequency differences implies no population stratification along taxonomic lines. This suggested that there is little concern for cryptic hybridization when sampling from sites of sympatry for LD mapping.

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This paper presents the site classification of Bangalore Mahanagar Palike (BMP) area using geophysical data and the evaluation of spectral acceleration at ground level using probabilistic approach. Site classification has been carried out using experimental data from the shallow geophysical method of Multichannel Analysis of Surface wave (MASW). One-dimensional (1-D) MASW survey has been carried out at 58 locations and respective velocity profiles are obtained. The average shear wave velocity for 30 m depth (Vs(30)) has been calculated and is used for the site classification of the BMP area as per NEHRP (National Earthquake Hazards Reduction Program). Based on the Vs(30) values major part of the BMP area can be classified as ``site class D'', and ``site class C'. A smaller portion of the study area, in and around Lalbagh Park, is classified as ``site class B''. Further, probabilistic seismic hazard analysis has been carried out to map the seismic hazard in terms spectral acceleration (S-a) at rock and the ground level considering the site classes and six seismogenic sources identified. The mean annual rate of exceedance and cumulative probability hazard curve for S. have been generated. The quantified hazard values in terms of spectral acceleration for short period and long period are mapped for rock, site class C and D with 10% probability of exceedance in 50 years on a grid size of 0.5 km. In addition to this, the Uniform Hazard Response Spectrum (UHRS) at surface level has been developed for the 5% damping and 10% probability of exceedance in 50 years for rock, site class C and D These spectral acceleration and uniform hazard spectrums can be used to assess the design force for important structures and also to develop the design spectrum.

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Surgical treatment of lumbar spinal stenosis (LSS) is a treatment option for those patients who remain severely symptomatic after a course of conservative treatment. Majority of the patients treated surgically enjoy good-to-excellent outcomes with respect to pain alleviation and functional recovery. However, between 20% and 40% of the patients who have surgery for LSS do not benefit from it. The knowledge of the psychological factors associated with recovery and treatment outcome is still scarce. The aim of this study was to assess LSS patients selected for surgical treatment. Specifically, the study assessed the prevalence of depression (Beck Depression Inventory, BDI) before surgical treatment and three months after the treatment. Also preoperative life satisfaction (four-item Life Satisfaction scale) of the LSS patients was studied. Furthermore, the patients satisfaction with surgery outcome at the three months postoperative stage was studied. One-fifth (20%) of the LSS-patients were found to have depression preoperatively. The patients assessments of the pain intensity or location were not associated with depression. The factors that did associate with depression were subjective disability of everyday living and poor life satisfaction. In addition to this, low sense of coherence and poor life satisfaction were associated with depression in logistic regression models. Significant associations were seen between preoperative depression and postoperative high disability scores, high symptom severity scores and higher pain intensity ratings. The patients with continuous depression (60% of the patients who had preoperative depression) showed less improvement in symptom severity, disability, pain and walking capacity than the patients who did not experience depression at any stage. In those patients who recovered from depression (35% of the patients with preoperative depression), the postoperative improvement was rather similar to the improvement seen in the normal mood group. One-fourth (25%) of the preoperative patients with LSS were found to be dissatisfied with life. The dissatisfied patients were significantly younger and had more self-reported somatic comorbidity. The dissatisfied patients had also elevated subjective disability scores and more extensive pain locations. Also lower coping resources and higher BDI scores were associated with life dissatisfaction. Younger age and somatic comorbidity were associated with life dissatisfaction in regression models. Two-thirds (66%) of the patients were at least clearly satisfied with the surgery outcome at three months postoperative stage. In group comparisons, the lack of physical, functional and emotional well-being was associated with the patients dissatisfaction with the surgery outcome. Younger age, postoperative symptom severity, disability and depression were independently associated with dissatisfaction with the surgery outcome. The results show that depression and psychological well-being are important factors with respect to LSS patients functional ability and recovery both before and three months after surgical treatment. Therefore, the clinical practice recommendations should include an assessment of depression

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Grain produced from doubled-haploid (DH) wheat lines, developed from a hard- and a soft-grained wheat cultivar, were bulked according to Pinb (puroindoline b) genotypes for an assessment of Chinese fresh noodle texture by a trained taste panel. Each DH line was designated as 'soft' or 'hard' grained, based on a PCR amplification of the wildtype, soft allele, or the mutant, hard allele. Theoretically, the soft and hard grain bulks represented respective Pinb alleles and an independent assortment of unlinked alleles from the parents, Sunco and Chuanyu 12. Grains from the parents and DH lines were grown at 2 locations in Queensland, Australia, and one in Sichuan, China. The grains were milled and processed for a taste panel evaluation in Chengdu, Sichuan. Results suggest the Pinb alleles had a significant effect on noodle softness and explained 30% of the variation; the 'soft' Pinb allele conferred a softer noodle texture. Location had a significant effect on noodle smoothness; wheat grain grown at Biloela, Queensland, produced a smoother noodle texture than grain grown in Sichuan. The effect of location confirms the importance of environment as a variable for this quality character. This investigation exemplifies the utility of Pinb markers for specifically altering Chinese Fresh Noodle texture.

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Root-lesion nematode (Pratylenchus thornei) is a serious pathogen of wheat in many countries. The International Triticeae Mapping Initiative (ITMI) population of recombinant inbred lines (RILs) was assessed for resistance to P. thornei to determine the chromosome locations of the resistance genes. The ITMI population is derived from a cross between the resistant synthetic hexaploid wheat W-7984 and a susceptible bread wheat cultivar Opata 85. Two years of phenotypic data for resistance to P. thornei were obtained in replicated glasshouse trials. Quantitative trait locus (QTL) analysis was performed using available segregation and map data for 114 RILs. A QTL on chromosome 6DS showed consistent effects for reduced nematode numbers (partial resistance) across years and accounted for 11% and 23% of the phenotypic variation. A second QTL for P. thornei resistance on chromosome 2BS accounted for an additional 19% and 5%. Restriction fragment length polymorphism (RFLP) and simple sequence repeat (SSR) markers associated with the QTLs are physically located in regions rich in major genes at the distal ends of the short chromosome arms of 6D and 2B. SSR markers with potential for marker-assisted selection of P. thornei resistance effective in different genetic backgrounds have been identified.

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Odour emission rates were measured for seven different anaerobic ponds treating piggery wastes at six to nine discrete locations across the surface of each pond on each sampling occasion over a thirteen month period. Significant variability in emission rates were observed for each pond. Measurement of a number of water quality variables in pond liquor samples collected at the same time and from the same locations as the odour samples indicated that the composition of the pond liquor was also variable. The results indicated that spatial variability was a real phenomenon and could have a significant impact on odour assessment practices. Considerably more odour samples would be required to characterise pond emissions than currently recommended by most practitioners, or regulatory agencies.

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Odour emission rates were measured for seven different anaerobic ponds treating piggery wastes at six to nine discrete locations across the surface of each pond on each sampling occasion over a 14-month period. Emission rate values varied between ponds, between seasons for the same pond and even for the same pond on different days of a sampling week. Average seasonal emission rates ranged from 7.9 to 46.5 OU/m2 s, while average emission rates ranged from 16.0 to 29.0 OU/m2 s. Factors potentially responsible for the variability in emission rates were investigated, including air and pond liquor temperatures, time of day of sample collection, season and the impact of a prolonged drought.

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The most common explanation for species diversity increasing towards the tropics is the corresponding increase in habitats (spatial heterogeneity). Consequently, a monoculture (like cotton in Australia) which is grown along a latitudinal gradient, should have the same degree of species diversity throughout its range. We tested to see if diversity in a dominant cotton community (spiders) changed with latitude, and if the community was structurally identical in different parts of Australia. We sampled seven sites extending over 20 degrees of latitude. At each site we sampled 1-3 fields 3-5 times during the cotton growing season using pitfall traps and beatsheets, recording all the spiders collected to family. We found that spider communities in cotton are diverse, including a large range of foraging guilds, making them suitable for a conservation biological control programme. We also found that spider diversity increased from high to low latitudes, and the communities were different, even though the spiders were in the same monocultural habitat. Spider beatsheet communities around Australia were dominated by different families, and responded differently to seasonal changes, indicating that different pest groups would be targeted at different locations. These results show that diversity can increase from high to low latitudes, even if spatial heterogeneity is held constant, and that other factors external to the cotton crop are influencing spider species composition. Other models which may account for the latitudinal gradient, such as non-equilibrium regional processes, are discussed.

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Linear mixed models were used to test the null hypothesis that there were no differences between seasons and locations in the reproductive potential of female eastern king prawns, Melicertus plebejus along the east coast of Australia. Three samples were collected in each season between autumn 1991 and winter 1992 (inclusive). Females capable of spawning were found at all locations but proportions were greater in lower than higher latitudes. Females capable of spawning were not found at the southern (highest latitude) most location in all seasons. There was a significant interaction in reproductive potential between seasons and locations suggesting that patterns among seasons differed between locations and vice versa. Reproductive potential was greatest amongst the northern (lower latitudes) most locations and was greatest in autumn at these locations. Seasonal patterns were less pronounced further south (higher latitudes). The length composition of females in catches differed between locations with more larger prawns found in samples from northern locations. The challenge that remains is to quantify the oceanic sources of larvae that contribute to recruitment in each nursery area and the estuarine sources of juveniles that contribute adults back to the effective spawning stock. Maintaining the effective spawning stock and important nursery areas are crucial to the sustainability of this resource.

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Different strategies for functionalization of the core region and periphery of core-shell type hyperbranched polymers (HBP) using the ``click'' reaction have been explored. For achieving periphera functionalization, an AB(2) + A-R-1 + A-R-2 type copolymerization approach was used, where A-R-1 is heptaethylene glycol monomethyl ether (HPEG-M) and A-R-2 is tetraethylene glycol monopropargyl ether (TEG-P). A very small mole fraction of the propargyl containing monomer, TEG-P, was used to ensure that the water-solubility of the hyperbranched polymer is minimally affected. Similarly, to incorporate propargyl groups in the core region, a new propargyl group bearing B-2-typ monomer was designed and utilized in an AB(2) + A(2) + B-2 + A-R-1 type copolymerization, such that the total mole fraction of B-2 + A(2) is small and their mole-ratio is 1: 1. Further, using a combination of both the above approaches, namely AB(2) + A(2) + B-2 + A-R-1 + A-R-2, hyperbranched structures that incorporate propargyl groups both at theperiphery and within the core were synthesized. Since the AB(2) monomer carries a hexamethylene spacer (C-6) and the periphery is PEGylated all the derivatized polymers form core-shell type structures in aqueous solutions. Attempts were made to ascertain and probe the location of the propargyl groups in these HBP's, by ``clicking'' azidomethylpyrene, onto them. However, the fluorescence spectra of aqueous solutions of the pyrene derivatized polymers were unable to discriminate between the various locations, possibly because the relatively hydrophobic pyrene units insert themselves into the core region to minimize exposure to water.

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Many forces are driving the global demand for assurance that fruit and vegetables are safe to eat and of the right quality, and are produced and handled in a manner that does not cause harm to the environment and the health, safety and welfare of workers. The impact of these driving forces is that retailer requirements for suppliers to comply with Good Agricultural Practice (GAP) is increasing and governments are strengthening legal requirements for food safety, environmental protection, and worker health, safety and welfare. The implementation of GAP programs currently within the ASEAN (Association of South East Asian Nations) region varies, with some countries having government certified systems and others beginning the journey with awareness programs for farmers. Under a project funded by the ASEAN Australia Development Cooperation Program, a standard for ASEAN GAP has been developed to harmonise GAP Programs in the region. The goal is to facilitate trade between ASEAN countries and to global markets, improve viability for farmers, and help sustain a safe food supply and the environment. ASEAN GAP is an umbrella standard that individual member countries will benchmark their national programs against to gain equivalence. The scope of ASEAN GAP covers the production, harvesting and postharvest handling of fresh fruit and vegetables on farm and postharvest handling in locations where produce is packed for sale. ASEAN GAP consists of four modules covering food safety, environmental management, worker health, safety and welfare, and produce quality. Each module can be used alone or in combination with other modules. This enables progressive implementation of ASEAN GAP, module by module based on individual country priorities.

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The amount and timing of early wet-season rainfall are important for the management of many agricultural industries in north Australia. With this in mind, a wet-season onset date is defined based on the accumulation of rainfall to a predefined threshold, starting from 1 September, for each square of a 1° gridded analysis of daily rainfall across the region. Consistent with earlier studies, the interannual variability of the onset dates is shown to be well related to the immediately preceding July-August Southern Oscillation index (SOI). Based on this relationship, a forecast method using logistic regression is developed to predict the probability that onset will occur later than the climatological mean date. This method is expanded to also predict the probabilities that onset will be later than any of a range of threshold dates around the climatological mean. When assessed using cross-validated hindcasts, the skill of the predictions exceeds that of climatological forecasts in the majority of locations in north Australia, especially in the Top End region, Cape York, and central Queensland. At times of strong anomalies in the July-August SOI, the forecasts are reliably emphatic. Furthermore, predictions using tropical Pacific sea surface temperatures (SSTs) as the predictor are also tested. While short-lead (July-August predictor) forecasts are more skillful using the SOI, long-lead (May-June predictor) forecasts are more skillful using Pacific SSTs, indicative of the longer-term memory present in the ocean.

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Pratylenchus thornei and P. neglectus are two species of root-lesion nematode that cause substantial yield losses in wheat. No commercially available wheat variety has resistance to both species. A doubled-haploid population developed from a cross between the synthetic hexaploid wheat line CPI133872 and the bread wheat Janz was used to locate and tag quantitative trait loci (QTLs) associated with resistance to both P. thornei and P. neglectus. Wheat plants were inoculated with both species of nematode in independent replicated glasshouse trials repeated over 2 years. Known locations of wheat microsatellite markers were used to construct a framework map. After an initial single-marker analysis to detect marker-trait linkages, chromosome regions associated with putative QTLs were targetted with microsatellite markers to increase map density in the chromosome regions of interest. In total, 148 wheat microsatellite markers and 21 amplified fragment length polymorphism markers were mapped. The codominant microsatellite marker Xbarc183 on the distal end of chromosome 6DS was allelic for resistance to both P. thornei and P. neglectus. The QTL were designated QRlnt.lrc-6D.1 and QRlnn.lrc-6D.1, for the 2 traits, respectively. The allele inherited from CPI133872 explained 22.0-24.2% of the phenotypic variation for P. thornei resistance, and the allele inherited from Janz accounted for 11.3-14.0% of the phenotypic variation for P. neglectus resistance. Composite interval mapping identified markers that flank a second major QTL on chromosome 6DL (QRlnt.lrc-6D.2) that explained 8.3-13.4% of the phenotypic variation for P. thornei resistance. An additional major QTL associated with P. neglectus resistance was detected on chromosome 4DS (QRlnn.lrc-4D.1) and explained a further 10.3-15.4% of the phenotypic variation. The identification and tagging of nematode resistance genes with molecular markers will allow appropriate allele combinations to be selected, which will aid the successful breeding of wheat with dual nematode resistance.