998 resultados para Morrison, Maynard


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Improved sequencing technologies offer unprecedented opportunities for investigating the role of rare genetic variation in common disease. However, there are considerable challenges with respect to study design, data analysis and replication. Using pooled next-generation sequencing of 507 genes implicated in the repair of DNA in 1,150 samples, an analytical strategy focused on protein-truncating variants (PTVs) and a large-scale sequencing case-control replication experiment in 13,642 individuals, here we show that rare PTVs in the p53-inducible protein phosphatase PPM1D are associated with predisposition to breast cancer and ovarian cancer. PPM1D PTV mutations were present in 25 out of 7,781 cases versus 1 out of 5,861 controls (P = 1.12 × 10-5), including 18 mutations in 6,912 individuals with breast cancer (P = 2.42 × 10-4) and 12 mutations in 1,121 individuals with ovarian cancer (P = 3.10 × 10-9). Notably, all of the identified PPM1D PTVs were mosaic in lymphocyte DNA and clustered within a 370-base-pair region in the final exon of the gene, carboxy-terminal to the phosphatase catalytic domain. Functional studies demonstrate that the mutations result in enhanced suppression of p53 in response to ionizing radiation exposure, suggesting that the mutant alleles encode hyperactive PPM1D isoforms. Thus, although the mutations cause premature protein truncation, they do not result in the simple loss-of-function effect typically associated with this class of variant, but instead probably have a gain-of-function effect. Our results have implications for the detection and management of breast and ovarian cancer risk. More generally, these data provide new insights into the role of rare and of mosaic genetic variants in common conditions, and the use of sequencing in their identification.

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Background Exposure to air pollutants, including diesel particulate matter, has been linked to adverse respiratory health effects. Inhaled diesel particulate matter contains adsorbed organic compounds. It is not clear whether the adsorbed organics or the residual components are more deleterious to airway cells. Using a physiologically relevant model, we investigated the role of diesel organic content on mediating cellular responses of primary human bronchial epithelial cells (HBECs) cultured at an air-liquid interface (ALI). Methods Primary HBECs were cultured and differentiated at ALI for at least 28 days. To determine which component is most harmful, we compared primary HBEC responses elicited by residual (with organics removed) diesel emissions (DE) to those elicited by neat (unmodified) DE for 30 and 60 minutes at ALI, with cigarette smoke condensate (CSC) as the positive control, and filtered air as negative control. Cell viability (WST-1 cell proliferation assay), inflammation (TNF-α, IL-6 and IL-8 ELISA) and changes in gene expression (qRT-PCR for HO-1, CYP1A1, TNF-α and IL-8 mRNA) were measured. Results Immunofluorescence and cytological staining confirmed the mucociliary phenotype of primary HBECs differentiated at ALI. Neat DE caused a comparable reduction in cell viability at 30 or 60 min exposures, whereas residual DE caused a greater reduction at 60 min. When corrected for cell viability, cytokine protein secretion for TNF-α, IL-6 and IL-8 were maximal with residual DE at 60 min. mRNA expression for HO-1, CYP1A1, TNF-α and IL-8 was not significantly different between exposures. Conclusion This study provides new insights into epithelial cell responses to diesel emissions using a physiologically relevant aerosol exposure model. Both the organic content and residual components of diesel emissions play an important role in determining bronchial epithelial cell response in vitro. Future studies should be directed at testing potentially useful interventions against the adverse health effects of air pollution exposure.

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Genome-wide association studies (GWASs) have been successful at identifying single-nucleotide polymorphisms (SNPs) highly associated with common traits; however, a great deal of the heritable variation associated with common traits remains unaccounted for within the genome. Genome-wide complex trait analysis (GCTA) is a statistical method that applies a linear mixed model to estimate phenotypic variance of complex traits explained by genome-wide SNPs, including those not associated with the trait in a GWAS. We applied GCTA to 8 cohorts containing 7096 case and 19 455 control individuals of European ancestry in order to examine the missing heritability present in Parkinson's disease (PD). We meta-analyzed our initial results to produce robust heritability estimates for PD types across cohorts. Our results identify 27% (95% CI 17-38, P = 8.08E - 08) phenotypic variance associated with all types of PD, 15% (95% CI -0.2 to 33, P = 0.09) phenotypic variance associated with early-onset PD and 31% (95% CI 17-44, P = 1.34E - 05) phenotypic variance associated with late-onset PD. This is a substantial increase from the genetic variance identified by top GWAS hits alone (between 3 and 5%) and indicates there are substantially more risk loci to be identified. Our results suggest that although GWASs are a useful tool in identifying the most common variants associated with complex disease, a great deal of common variants of small effect remain to be discovered. © Published by Oxford University Press 2012.

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We performed a genome-wide association study (GWAS) in 1705 Parkinson's disease (PD) UK patients and 5175 UK controls, the largest sample size so far for a PD GWAS. Replication was attempted in an additional cohort of 1039 French PD cases and 1984 controls for the 27 regions showing the strongest evidence of association (P < 10 4). We replicated published associations in the 4q22/SNCA and 17q21/MAPT chromosome regions (P < 10 10) and found evidence for an additional independent association in 4q22/SNCA.A detailed analysis of the haplotype structure at 17q21 showed that there are three separate risk groups within this region. We found weak but consistent evidence of association for common variants located in three previously published associated regions (4p15/BST1, 4p16/GAK and 1q32/PARK16). We found no support for the previously reported SNP association in 12q12/LRRK2. We also found an association of the two SNPs in 4q22/SNCA with the age of onset of the disease. © The Author 2010. Published by Oxford University Press.

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This paper is an extension of Talking Green in Red States: Stories from the Great Plains (Gibson et al., 2014) that examined the communication strategies of planners involved in sustainability planning initiatives in the U.S. Great Plains. We expand these narratives beyond the Great Plains to Queensland, Australia by interviewing planners about their experiences when communicating and deliberating about issues of sustainability. Using a semi-formal structure, interviews are conducted as casual “coffee talks” (Maynard-Moody & Musheno, 2003). Together, these collected stories help us to understand how planners are “talking green” in conservative political atmospheres, across vastly differing geographies using an international comparative framework described by Reimer et al. (2014). The paper presents comparisons between the collected narratives, concerning similarities and differences in regard to the nuances of sustainability planning dialog. We relate the lessons learned about communication strategies of planners working in sustainability in Kansas and Queensland to the broader discourse of planning and politics, communicative planning and planning as storytelling, as they relate to sustainability planning in challenging situations. From this paper, the audience will better understand how: 1) to discuss environmental and sustainable planning in communities that have varying levels of distrust and suspicion towards these concepts; 2) to develop strategies to work around these planning communication issues, and; 3) international context affects these communication challenges.

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Purpose To determine whether melanopsin expressing intrinsically photosensitive Retinal Ganglion Cell (ipRGC) inputs to the pupil light reflex (PLR) are affected in early age-related macular degeneration (AMD). Methods The PLR was measured in 40 participants (20 early AMD and 20 age-matched controls) using a custom-built Maxwellian-view pupillometer. Sinusoidal stimuli (0.5 Hz, 11.9 s duration, 35.6° diameter) were presented to the study eye and the consensual pupil response was measured for stimuli with high melanopsin excitation (464nm; blue) and with low melanopsin excitation (638 nm; red) that biased activation to the outer retina. Two melanopsin PLR metrics were quantified: the Phase Amplitude Percentage (PAP) during the sinusoidal stimulus presentation and the Post-Illumination Pupil Response (PIPR). The PLR during stimulus presentation was analyzed using latency to constriction, transient pupil response and maximum pupil constriction metrics. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curves. Results The blue PIPR was significantly less sustained in the early AMD group (p<0.001). The red PIPR was not significantly different between groups (p>0.05). The PAP and blue stimulus constriction amplitude were significantly lower in the early AMD group (p < 0.05). There was no significant difference between groups in the latency or transient amplitude for both stimuli (p>0.05). ROC analysis showed excellent diagnostic accuracy for the blue PIPR metrics (AUC>0.9). Conclusions This is the initial report that the melanopsin controlled PIPR is dysfunctional in early AMD. The non-invasive, objective measurement of the ipRGC controlled PIPR has excellent diagnostic accuracy for early AMD.

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Purpose Melanopsin-expressing retinal ganglion cells (mRGCs) have non-image forming functions including mediation of the pupil light reflex (PLR). There is limited knowledge about mRGC function in retinal disease. Initial retinal changes in age-related macular degeneration (AMD) occur in the paracentral region where mRGCs have their highest density, making them vulnerable during disease onset. In this cross-sectional clinical study, we measured the PLR to determine if mRGC function is altered in early stages of macular degeneration. Methods Pupil responses were measured in 8 early AMD patients (AREDS 2001 classification; mean age 72.6 ± 7.2 years, 5M, and 3F) and 12 healthy control participants (mean age 66.6 ± 6.1 years, 8M and 4F) using a custom-built Maxwellian-view pupillometer. Stimuli were 0.5 Hz sinewaves (10 s duration, 35.6° diameter) of short wavelength light (464nm, blue; retinal irradiance = 14.5 log quanta.cm-2.s-1) to produce high melanopsin excitation and of long wavelength light (638nm, red; retinal irradiance = 14.9 log quanta.cm-2.s-1), to bias activation to outer retina and provide a control. Baseline pupil diameter was determined during a 10 s pre-stimulus period. The post illumination pupil response (PIPR) was recorded for 40 s. The 6 s PIPR and maximum pupil constriction were expressed as percentage baseline (M ± SD). Results The blue PIPR was significantly less sustained (p<0.01) in the early AMD group (75.49 ± 7.88%) than the control group (58.28 ± 9.05%). The red PIPR was not significantly different (p>0.05) between the early AMD (84.79 ± 4.03%) and control groups (82.01 ± 5.86%). Maximum constriction amplitude in the early AMD group for blue (43.67 ± 6.35%) and red (48.64 ± 6.49%) stimuli were not significantly different to the control group for blue (39.94 ± 3.66%) and red (44.98 ± 3.15%) stimuli (p>0.05). Conclusions These results are suggestive of inner retinal mRGC deficits in early AMD. This non-invasive, objective measure of pupil responses may provide a new method for quantifying mRGC function and monitoring AMD progression.

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In his 2013 three-minute speech on unacceptable behaviour in the workplace, Lieutenant General David Morrison makes the above insightful statement. While the context of the speech is the defence force, the meaning of the powerful message holds true for perioperative nursing. Perioperative nurses are part of a profession. Professions Australia, a national organisation of professional associations which aims to advance and promote professionalism for the benefit of the community, provides us with a definition of a profession2 and perioperative nurses meet this definition. Perioperative nurses possess special knowledge and skills grounded in a widely recognised body of discipline knowledge derived from research, education and high-level training. We control and regulate our own boundaries of work. We adhere to ethical and professional standards and values. Specialty professional practice standards define perioperative nurses as a community of professionals — assisting perioperative nurses when advocating for consistency in quality patient care3. It is an imperative for every professional perioperative nurse to model practice underpinned by the ACORN Standards throughout their workplace. Hence, Lieutenant General Morrison’s profound statement is a mantra each perioperative nurse could readily adopt and model in their practice environment...

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This thesis presents an interdisciplinary analysis of how models and simulations function in the production of scientific knowledge. The work is informed by three scholarly traditions: studies on models and simulations in philosophy of science, so-called micro-sociological laboratory studies within science and technology studies, and cultural-historical activity theory. Methodologically, I adopt a naturalist epistemology and combine philosophical analysis with a qualitative, empirical case study of infectious-disease modelling. This study has a dual perspective throughout the analysis: it specifies the modelling practices and examines the models as objects of research. The research questions addressed in this study are: 1) How are models constructed and what functions do they have in the production of scientific knowledge? 2) What is interdisciplinarity in model construction? 3) How do models become a general research tool and why is this process problematic? The core argument is that the mediating models as investigative instruments (cf. Morgan and Morrison 1999) take questions as a starting point, and hence their construction is intentionally guided. This argument applies the interrogative model of inquiry (e.g., Sintonen 2005; Hintikka 1981), which conceives of all knowledge acquisition as process of seeking answers to questions. The first question addresses simulation models as Artificial Nature, which is manipulated in order to answer questions that initiated the model building. This account develops further the "epistemology of simulation" (cf. Winsberg 2003) by showing the interrelatedness of researchers and their objects in the process of modelling. The second question clarifies why interdisciplinary research collaboration is demanding and difficult to maintain. The nature of the impediments to disciplinary interaction are examined by introducing the idea of object-oriented interdisciplinarity, which provides an analytical framework to study the changes in the degree of interdisciplinarity, the tools and research practices developed to support the collaboration, and the mode of collaboration in relation to the historically mutable object of research. As my interest is in the models as interdisciplinary objects, the third research problem seeks to answer my question of how we might characterise these objects, what is typical for them, and what kind of changes happen in the process of modelling. Here I examine the tension between specified, question-oriented models and more general models, and suggest that the specified models form a group of their own. I call these Tailor-made models, in opposition to the process of building a simulation platform that aims at generalisability and utility for health-policy. This tension also underlines the challenge of applying research results (or methods and tools) to discuss and solve problems in decision-making processes.

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Approaches to manage for the sustainable use of natural and cultural resources in a landscape can have many different designs. One design is adaptive collaborative landscape management (ACLM) where research providers and users work closely together on projects to develop resources while adaptively managing to sustain or maintain landscapes in the long term. We propose that collaborative projects are more useful for achieving outcomes than integrative projects where participants merely join their separate contributions. To foster collaborative research projects to adaptively manage landscapes in northern Australia, a Tropical Savannas Cooperative Research Centre (TSCRC) was established in 1995. The TSCRC is a joint venture of major organizations involved in research and land management. This paper is our perspective on the four most important 'lessons learned' after using a ACLM-type approach for over 10 y. We learnt that collaboration (working in combination) not necessarily integration (combining parts into a whole) achieved sustainable outcomes. We found that integration across culturally diverse perspectives seldom achieved sustainable solutions because it devalued the position of the less empowered participants. In addition, positive outcomes were achieved when participants developed trust and respect for each other by embracing and respecting their differences and by sharing unifying concepts such as savanna health. Another lesson learned was that a collaborative organization must act as an honest broker by resisting advocacy of one view point over another. Finally, we recognized the importance of strongly investing in communication and networking so that people could adaptively learn from one another's experiences, understand each other's challenges and respect each other's choices. Our experience confirms the usefulness of the ACLM approach and highlights its role in the process of sustaining healthy landscapes.

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This article describes research designed to determine the molasses addition rates that can control ammonia and pH in eutrophic aquaculture ponds.

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To assess their utility for profitable wastewater bioremediation, banana prawns, Penaeus (Fenneropenaeus) merguiensis (de Man), were stocked at low densities (1 – 5 m-2) and grown without supplemental feeding in five commercial-prawn-farm settlement ponds (0.3 to 6.0 ha). The prawns free-ranged in the variously designed ponds for 160 to 212 days after stocking as PL15. Survival estimates ranged from 12% to 60% with production of 50 – 528 kg ha-1. Over 1150 kg of marketable product was produced in the study. Exceptional growth was monitored at one farm where prawns reached an average size of 17g in 80 days. Nutrients in water flowing into (8 - 40 ML d-1) and out of the settlement pond at that farm were assessed twice weekly along with routine water quality measurements. Only small differences in water qualities were detected between waters running into and out of this settlement pond. Total nitrogen levels gradually increased from 1 - 1.5 mg L-1 early in the season to over 3 mg L-1 towards the end of the season. Total phosphorus levels similarly rose from 0.1 - 0.2 mg L-1 to 0.3 - 0.4 mg L-1 in the middle of the season, but fell to 0.2 – 0.3 mg L-1 towards the end when approximately 12,000 prawns were harvested with a total weight of 175 kg. No significant differences (P > 0.05) were detected in the overall acceptability of prawns harvested from each of the 5 settlement ponds in small-scale consumer sensory analyses. The prawns from settlement ponds were rated similarly to banana prawns grown with commercial diets at two other establishments. Microbiological analyses of prawns from all farms showed bacterial levels to be well within food-grade standards and lower than prawns produced in a normal growout pond. These results demonstrate that high quality food grade banana prawns can be produced in these wastewater treatment systems.

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To experimentally investigate the effect of vertical artificial substrate and different densities of the banana prawn Penaeus (Fenneropenaeus) merguiensis on nutrient levels in prawn pond effluent, a time series experiment was conducted in a replicated tank system supplied periodically with discharge from a prawn production pond. Few differences (P>0.05) were detected between tanks without prawns, and tanks with low densities (5 prawns in 1700 litres) of prawns (10-12 g), in terms of nitrogen and phosphorus in the water column over the 28-day experimental period. Higher densities of prawns (starting at 25 or 50 per tank) caused an elevation of these macronutrients in the water column. This was partly due to prawn biomass losses from mortalities and weight reductions in the tank system. The survival and condition of prawns was significantly (P<0.05) reduced in tanks at these higher densities. The presence of artificial substrate (2 m2 tank-1) did not affect (P>0.05) the levels of nutrients in tank water columns, but significantly (P<0.05) increased the amount of nitrogen in tank residues left at the end of the trial when no prawns were present. The prawns had obviously been grazing on surfaces inside the tanks, and their swimming actions appeared to keep light particulate matter in suspension. Higher prawn densities increased microalgal blooms, which presumably kept ammonia levels low, and it is suggested that this association may provide the means for improved remediation of prawn farm effluent in the future.

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To experimentally investigate the potential of mixed species polycultures for bioremediation of nutrient rich prawn farm effluent, a series of experiments was performed with banana prawns Penaeus (Fenneropenaeus) merguiensis, sea mullet Mugil cephalus and rabbitfish Siganus nebulosus to determine their compatibilities during particular life stages. Rabbitfish demonstrated a high tendency to prey upon banana prawn juveniles when no other food was available. Mullet of various sizes did not appear to prey upon banana prawn postlarvae (PL16) or juveniles in a fed or unfed environment. The study confirms the good potential for mullet and banana prawn polycultures.

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To experimentally investigate the effect of the “SKIM” mechanical foam fractionator on suspended material and the nutrient levels in prawn farm effluent, a series of standardised short-term treatments were applied to various effluent types in a static 10,000-litre water body. Prawn pond effluents were characterised by watercolour and dominance of phytoplankton species. Three effluent types were tested, namely 1) particulate-rich effluent with little apparent phytoplankton, 2) green mircoalgal bloom predominately made up of single celled phytoplankton, and 3) brown microalgal bloom with higher prevalence of diatoms. The effluent types were similar (P>0.05) in non-volatile particulate material, and nitrate/nitrite but varied from each other in the following ways: 1) The particulate-rich effluents were lower (P<0.05) in volatile solids (compared to brown blooms), total Kjeldahl nitrogen, dissolved organic nitrogen, dissolved organic phosphorus and chlorophyll a (compared to both green and brown blooms). 2) The brown blooms were higher (P<0.05) in ammonia (compared to green blooms), total nitrogen and total phosphorus (compared to both green and particulate-rich effluent), but were lower (P<0.05) in inorganic phosphorus (compared to both green and particulate-rich effluent). 3) The green blooms were higher (P<0.05) in dissolved (both organic and inorganic) phosphorus (compared to both brown and particulate-rich effluents). Although the effluent types varied significantly in these aspects the effect of the Skim treatment was similar for all parameters measured except total phosphorus. Bloom type and Skim-treatment period significantly (P<0.05) affected total Kjeldahl phosphorus concentrations. For all effluent types there was a continuous significant reduction (P<0.05) in total Kjeldahl phosphorus during the initial 6-hour treatment period. Levels of total suspended solids and volatile suspended solids in all effluent types were significantly (P<0.05) reduced in the first 2 hours but not thereafter. Non-volatile suspended solids were also significantly (P<0.05) reduced in the first 2 hours (30 to 40 % reduction) and a further 40% reduction occurred in the particulate-rich effluent over the next 2 hours. Mean values for total ammonia, dissolved organic nitrogen, total Kjeldahl nitrogen, total nitrogen, chlorophyll a and dissolved organic or inorganic phosphorus levels were not significantly (P>0.05) affected by the Skim unit in any bloom type during the initial 6 hours of testing. Nevertheless, non-significant nitrogen reductions did occur. Foam production by the Skim unit varied with different blooms, resulting in different concentrate volumes and different end points for separate experiments. Concentrate volumes were generally high for the particulate-rich and green blooms (175 – 370 litres) and low for the brown blooms (25 – 80 litres). This was due to the low tendency of the brown bloom to produce foam. This generated higher nutrient concentrations in the associated condensed foam, but may have limited the treatment efficiency. The results suggest that in this application, the Skim unit did not remove micro-algae as effectively as was anticipated. However, it was effective at removing other suspended solids. Considering these attributes and the other uses of this machinery documented by the manufactures, the unit’s oxygenation mixing capacities coupled with inorganic solids removal may provide a suitable mechanism for construction of a continuously mixed bioreactor that utilises the filtration and profit making abilities of bivalves.