1000 resultados para Southern Spectrophotometric Standards


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Drug Analysis without Primary Reference Standards: Application of LC-TOFMS and LC-CLND to Biofluids and Seized Material Primary reference standards for new drugs, metabolites, designer drugs or rare substances may not be obtainable within a reasonable period of time or their availability may also be hindered by extensive administrative requirements. Standards are usually costly and may have a limited shelf life. Finally, many compounds are not available commercially and sometimes not at all. A new approach within forensic and clinical drug analysis involves substance identification based on accurate mass measurement by liquid chromatography coupled with time-of-flight mass spectrometry (LC-TOFMS) and quantification by LC coupled with chemiluminescence nitrogen detection (LC-CLND) possessing equimolar response to nitrogen. Formula-based identification relies on the fact that the accurate mass of an ion from a chemical compound corresponds to the elemental composition of that compound. Single-calibrant nitrogen based quantification is feasible with a nitrogen-specific detector since approximately 90% of drugs contain nitrogen. A method was developed for toxicological drug screening in 1 ml urine samples by LC-TOFMS. A large target database of exact monoisotopic masses was constructed, representing the elemental formulae of reference drugs and their metabolites. Identification was based on matching the sample component s measured parameters with those in the database, including accurate mass and retention time, if available. In addition, an algorithm for isotopic pattern match (SigmaFit) was applied. Differences in ion abundance in urine extracts did not affect the mass accuracy or the SigmaFit values. For routine screening practice, a mass tolerance of 10 ppm and a SigmaFit tolerance of 0.03 were established. Seized street drug samples were analysed instantly by LC-TOFMS and LC-CLND, using a dilute and shoot approach. In the quantitative analysis of amphetamine, heroin and cocaine findings, the mean relative difference between the results of LC-CLND and the reference methods was only 11%. In blood specimens, liquid-liquid extraction recoveries for basic lipophilic drugs were first established and the validity of the generic extraction recovery-corrected single-calibrant LC-CLND was then verified with proficiency test samples. The mean accuracy was 24% and 17% for plasma and whole blood samples, respectively, all results falling within the confidence range of the reference concentrations. Further, metabolic ratios for the opioid drug tramadol were determined in a pharmacogenetic study setting. Extraction recovery estimation, based on model compounds with similar physicochemical characteristics, produced clinically feasible results without reference standards.

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The purpose of the present study was to explore the associations between good self-rated health and economic and social factors in different regions among ageing people in the Päijät-Häme region in southern Finland. The data of this study were collected in 2002 as part of the research and development project Ikihyvä 2002 2012 (Good Ageing in Lahti region GOAL project). The baseline data set consisted of 2,815 participants born in 1926 30, 1936 40, and 1946 50. The response rate was 66 %. According to the previous studies, trust in other people and social participation as the main aspects of social capital are associated with self-rated health. In addition, socioeconomic position (SEP) and self-rated health are associated, but all SEP indicators do not have identical associations with health. However, there is a lack of knowledge of the health associations and regional differences with these factors, especially among ageing people. Regarding these questions, the present study gives new information. According to the results of this study, self-perceived adequacy of income was significantly associated with good self-rated health, especially in the urban areas. Similar associations were found in the rural areas, though education was also considered an important factor. Adequacy of income was an even stronger predictor of good health than the actual income. Women had better self-rated health than men only in the urban areas. The youngest respondents had quite equally better self-rated health than the others. Social participation and access to help when needed were associated with good self-rated health, especially in the urban area and the sparsely populated rural areas. The result was comparable in the rural population centres. The correlation of trust with self-rated health was significant in the urban area. High social capital was associated with good self-rated health in the urban area. The association was quite similar in the other areas, though it was statistically insignificant. High social capital consisted of co-existent high social participation and high trust. The association of traditionalism (low participation and high trust) with self-rated health was also substantial in the urban area. The associations of self-rated health with low social capital (low participation and low trust) and the miniaturisation of community (high participation and low trust) were less significant. From the forms of single participation, going to art exhibitions, theatre, movies, and concerts among women, and studying and self-development among men were positively related to self-rated health. Unexpectedly, among women, active participation in religious events and voluntary work was negatively associated with self-rated health. This may indicate a coping method with ill-health. As a whole, only minor variations in self-rated health were found between the areas. However, the significance of the factors associated with self-rated health varied according to the areas. Economic factors, especially self-perceived adequacy of income was strongly associated with good self-rated health. Also when adjusting for economic and several other background factors social factors (particularly high social capital, social participation, and access to help when needed) were associated with self-rated health. Thus, economic and social factors have a significant relation with the health of the ageing, and improving these factors may have favourable effects on health among ageing people.

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The goal of the Program is to contribute to economic growth in the Philippines through increased income and improved livelihoods of tropical fruit growers in southern Philippines. The purpose of the Program is to improve the smallholder and industry profitability and export competitiveness of selected tropical fruits industries in the southern Philippines. Fruit crops to be targeted are mango, papaya, durian and jackfruit. The primary audience for the outcomes of this Program are medium to large scale commercial fruit growers and farmers predominantly in the regions of Leyte (VIII), northern Mindanao/Cagayan de Oro (X) and southern Mindanao/Davao (XI).

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The farming systems and agribusinesses of the inland Burnett and southern coastal cropping regions of Queensland are becoming increasingly interlinked as grain legume crops, a key component of dryland cropping systems, become more firmly entrenched in the coastal sugarcane cropping areas. Soybeans, peanuts and possibly winter cereals like barley have a real and demonstrated role in sugarcane rotations, and assistance with the integration of those crops into viable and sustainable cropping systems with sugarcane will be critical to the futuer development of these industries.

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Competency standards document the knowledge, skills, and attitudes required for competent performance. This study develops competency standards for dietitians in order to substantiate an approach to competency standard development. Focus groups explored the current and emerging purpose, role, and function of the profession, which were used to draft competency standards. Consensus was then sought using two rounds of a Delphi survey. Seven focus groups were conducted with 28 participants (15 employers/practitioners, 5 academics, 8 new graduates). Eighty-two of 110 invited experts participated in round one and 67 experts completed round two. Four major functions of dietitians were identified: being a professional, influencing the health of individuals, groups, communities, and populations through evidence-based nutrition practice, and working collaboratively in teams. Overall there was a high level of consensus on the standards: 93% achieved agreement by participants in round one and all revised standards achieved consensus on round 2. The methodology provides a framework for other professions wishing to embark on competency standard review or development.

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Aim: The requirement for an allied health workforce is expanding as the global burden of disease increases internationally. To safely meet the demand for an expanded workforce of orthotist/prosthetists in Australia, competency based standards, which are up-to-date and evidence-based, are required. The aims of this study were to determine the minimum level for entry into the orthotic/prosthetic profession; to develop entry level competency standards for the profession; and to validate the developed entry-level competency standards within the profession nationally, using an evidence-based approach. Methods: A mixed-methods research design was applied, using a three-step sequential exploratory design, where step 1 involved collecting and analyzing qualitative data from two focus groups; step 2 involved exploratory instrument development and testing, developing the draft competency standards; and step 3 involved quantitative data collection and analysis – a Delphi survey. In stage 1 (steps 1 and 2), the two focus groups – an expert and a recent graduate group of Australian orthotist/prosthetists – were led by an experienced facilitator, to identify gaps in the current competency standards and then to outline a key purpose, and work roles and tasks for the profession. The resulting domains and activities of the first draft of the competency standards were synthesized using thematic analysis. In stage 2 (step 3), the draft-competency standards were circulated to a purposive sample of the membership of the Australian Orthotic Prosthetic Association, using three rounds of Delphi survey. A project reference group of orthotist/prosthetists reviewed the results of both stages. Results: In stage 1, the expert (n = 10) and the new graduate (n = 8) groups separately identified work roles and tasks, which formed the initial draft of the competency standards. Further drafts were refined and performance criteria added by the project reference group, resulting in the final draft-competency standards. In stage 2, the final draft-competency standards were circulated to 56 members (n = 44 final round) of the Association, who agreed on the key purpose, 6 domains, 18 activities, and 68 performance criteria of the final competency standards. Conclusion: This study outlines a rigorous and evidence-based mixed-methods approach for developing and endorsing professional competency standards, which is representative of the views of the profession of orthotist/prosthetists.

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Three species of Australian endemic catsharks (grey spotted catshark Asymbolus analis, orange spotted catshark A. rubiginosus and Australian sawtail shark Figaro boardmani) were collected from the trawl grounds of a highly seasonal commercial fishery off southern Queensland, Australia. Specimens were collected on the mid to outer continental shelf at depths between 78 and 168 m. This study provides the first information on the reproductive biology of these three poorly-known species. Mature female and male A. analis were observed from 455 mm total length (TL), mature female A. rubiginosus from 410 mm TL, mature male A. rubiginosus from 405 mm TL, mature female F. boardmani from 402 mm TL and mature male F. boardmani from 398 mm TL (although a lack of immature specimens precluded more accurate assessments of size at maturity). The reproductive mode of all species was confirmed as single oviparous (carrying only one egg case in each uterus at a time). Ovarian fecundity (the number of vitellogenic follicles) ranged from 7-20 in A. analis, 5-23 in A. rubiginosus and 9-13 in F. boardmani. Several indicators suggest that Asymbolus catsharks off southern Queensland are reproductively active year-round. The proportion of female A. rubiginosus carrying egg cases was highest in spring (60%), intermediate in autumn (50%) and lowest in winter (44%).

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Dairy farms located in the subtropical cereal belt of Australia rely on winter and summer cereal crops, rather than pastures, for their forage base. Crops are mostly established in tilled seedbeds and the system is vulnerable to fertility decline and water erosion, particularly over summer fallows. Field studies were conducted over 5 years on contrasting soil types, a Vertosol and Sodosol, in the 650-mm annual-rainfall zone to evaluate the benefits of a modified cropping program on forage productivity and the soil-resource base. Growing forage sorghum as a double-crop with oats increased total mean annual production over that of winter sole-crop systems by 40% and 100% on the Vertosol and Sodosol sites respectively. However, mean annual winter crop yield was halved and overall forage quality was lower. Ninety per cent of the variation in winter crop yield was attributable to fallow and in-crop rainfall. Replacing forage sorghum with the annual legume lablab reduced fertiliser nitrogen (N) requirements and increased forage N concentration, but reduced overall annual yield. Compared with sole-cropped oats, double-cropping reduced the risk of erosion by extending the duration of soil water deficits and increasing the time ground was under plant cover. When grown as a sole-crop, well fertilised forage sorghum achieved a mean annual cumulative yield of 9.64 and 6.05 t DM/ha on the Vertosol and Sodosol, respectively, being about twice that of sole-cropped oats. Forage sorghum established using zero-tillage practices and fertilised at 175 kg N/ha. crop achieved a significantly higher yield and forage N concentration than did the industry-standard forage sorghum (conventional tillage and 55 kg N/ha. crop) on the Vertosol but not on the Sodosol. On the Vertosol, mean annual yield increased from 5.65 to 9.64 t DM/ha (33 kg DM/kg N fertiliser applied above the base rate); the difference in the response between the two sites was attributed to soil type and fertiliser history. Changing both tillage practices and N-fertiliser rate had no affect on fallow water-storage efficiency but did improve fallow ground cover. When forage sorghum, grown as a sole crop, was replaced with lablab in 3 of the 5 years, overall forage N concentration increased significantly, and on the Vertosol, yield and soil nitrate-N reserves also increased significantly relative to industry-standard sorghum. All forage systems maintained or increased the concentration of soil nitrate-N (0-1.2-m soil layer) over the course of the study. Relative to sole-crop oats, alternative forage systems were generally beneficial to the concentration of surface-soil (0-0.1 m) organic carbon and systems that included sorghum showed most promise for increasing soil organic carbon concentration. We conclude that an emphasis on double-or summer sole-cropping rather than winter sole-cropping will advantage both farm productivity and the soil-resource base.

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Field studies were conducted over 5 years on two dairy farms in southern Queensland to evaluate the impacts of zero-tillage, nitrogen (N) fertiliser and legumes on a winter-dominant forage system based on raingrown oats. Oats was able to be successfully established using zero-tillage methods, with no yield penalties and potential benefits in stubble retention over the summer fallow. N fertiliser, applied at above industry-standard rates (140 vs. 55 kg/ha.crop) in the first 3 years, increased forage N concentration significantly and had residual effects on soil nitrate-N at both sites. At one site, crop yield was increased by 10 kg DM/ha. kg fertiliser N applied above industry-standard rates. The difference between sites in fertiliser response reflected contrasting soil and fertiliser history. There was no evidence that modifications to oats cropping practices (zero-tillage and increased N fertiliser) increased surface soil organic carbon (0-10 cm) in the time frame of the present study. When oats was substituted with annual legumes, there were benefits in improved forage N content of the oat crop immediately following, but legume yield was significantly inferior to oats. In contrast, the perennial legume Medicago sativa was competitive in biomass production and forage quality with oats at both sites and increased soil nitrate-N levels following termination. However, its contribution to winter forage was low at 10% of total production, compared with 40% for oats, and soil water reserves were significantly reduced at one site, which had an impact on the following oat production. The study demonstrated that productive grazed oat crops can be grown using zero tillage and that increased N fertiliser is more consistent in its effect on N concentration than on forage yield. A lucerne ley provides a strategy for raising soil nitrate-N concentration and increasing overall forage productivity, although winter forage production is reduced.

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Despite international protection of white sharks (Carcharodon carcharias), important conservation parameters such as abundance, population structure and genetic diversity are largely unknown. The tissue of 97 predominately juvenile white sharks sampled from spatially distant eastern and southwestern Australian coastlines was sequenced for the mitochondrial DNA (mtDNA) control region and genotyped with six nuclear-encoded microsatellite loci. MtDNA population structure was found between the eastern and southwestern coasts (FST = 0.142, p < 0.001), implying female natal philopatry. This concords with recent satellite and acoustic tracking findings which suggest the sustained presence of discrete east coast nursery areas. Furthermore, population subdivision was found between the same regions with biparentally inherited microsatellite markers (FST = 0.009, p <0.05), suggesting that males may also exhibit some degree of reproductive philopatry. Five sharks captured along the east coast had mtDNA haplotypes that resembled western Indian Ocean sharks more closely than Australian/New Zealand sharks, suggesting that transoceanic dispersal or migration resulting in breeding may occur sporadically. Our most robust estimate of contemporary genetic effective population size was low and below the threshold at which adaptive potential may be lost. For a variety of reasons, these contemporary estimates were at least one, possibly two orders of magnitude below our historical effective size estimates. Further population decline could expose these genetically isolated populations to detrimental genetic effects. Regional Australian white shark conservation management units should be implemented until genetic population structure, size and diversity can be investigated in more detail. Reference: Blower, D. C., Pandolfi, J. M., Gomez-Cabrera, M. del C., Bruce, B. D. & Ovenden, J. R. (In press - April 2012). Population genetics of Australian white sharks reveals fine-scale spatial structure, transoceanic dispersal events and low effective population sizes. Marine Ecology Progress Series.

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Certain bacteria present on frog skin can prevent infection by the pathogenic fungus Batrachochytrium dendrobatidis (Bd), conferring disease resistance. Previous studies have used agar-based in vitro challenge assays to screen bacteria for Bd-inhibitory activity and to identify candidates for bacterial supplementation trials. However, agar-based assays can be difficult to set up and to replicate reliably. To overcome these difficulties, we developed a semi-quantitative spectrophotometric challenge assay technique. Cell-free supernatants were prepared from filtered bacterial cultures and added to 96-well plates in replicated wells containing Bd zoospores suspended in tryptone-gelatin hydrolysate-lactose (TGhL) broth medium. Plates were then read daily on a spectrophotometer until positive controls reached maximum growth in order to determine growth curves for Bd. We tested the technique by screening skin bacteria from the Australian green-eyed tree frog Litoria serrata. Of bacteria tested, 31% showed some degree of Bd inhibition, while some may have promoted Bd growth, a previously unknown effect. Our cell-free supernatant challenge assay technique is an effective in vitro method for screening bacterial isolates for strong Bd-inhibitory activity. It contributes to the expanding field of bioaugmentation research, which could play a significant role in mitigating the effects of chytridiomycosis on amphibians around the world.

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Southern Hemisphere plantation forestry has grown substantially over the past few decades and will play an increasing role in fibre production and carbon sequestration in future. The sustainability of these plantations is, however, increasingly under pressure from introduced pests. This pressure requires an urgent and matching increase in the speed and efficiency at which tools are developed to monitor and control these pests. To consider the potential role of semiochemicals to address the need for more efficient pest control in Southern Hemisphere plantations, particularly by drawing from research in other parts of the world. Semiochemical research in forestry has grown exponentially over the last 40 years but has been almost exclusively focussed on Northern Hemisphere forests. In these forests, semiochemicals have played an important role to enhance the efficiency of integrated pest management programmes. An analysis of semiochemical research from 1970 to 2010 showed a rapid increase over time. It also indicated that pheromones have been the most extensively studied type of semiochemical in forestry, contributing to 92% of the semiochemical literature over this period, compared with research on plant kairomones. This research has led to numerous applications in detection of new invasions, monitoring population levels and spread, in addition to controlling pests by mass trapping or disrupting of aggregation and mating signals. The value of semiochemicals as an environmentally benign and efficient approach to managing forest plantation pests in the Southern Hemisphere seems obvious. There is, however, a lack of research capacity and focus to optimally capture this opportunity. Given the pressure from increasing numbers of pests and reduced opportunities to use pesticides, there is some urgency to develop semiochemical research capacity.