973 resultados para mixed-stock analysis


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Background
Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lepidopteran species in the Old and New Worlds respectively. Separation of H. armigera and H. zea is difficult and is usually only achieved through morphological differences in the genitalia. They are capable of interbreeding to produce fertile offspring. The single species status of H. armigera has been doubted, due to its wide distribution and plant host range across the Old World. This study explores the global genetic diversity of H. armigera and its evolutionary relationship to H zea.

Results
We obtained partial (511 bp) mitochondrial DNA (mtDNA) Cytochrome Oxidase-I (COI) sequences for 249 individuals of H. armigera sampled from Australia, Burkina Faso, Uganda, China, India and Pakistan which were associated with various host plants. Single nucleotide polymorphisms (SNPs) within the partial COI gene differentiated H. armigera populations into 33 mtDNA haplotypes. Shared haplotypes between continents, low F-statistic values and low nucleotide diversity between countries (0.0017 – 0.0038) suggests high mobility in this pest. Phylogenetic analysis of four major Helicoverpa pest species indicates that H. punctigera is basal to H. assulta, which is in turn basal to H. armigera and H. zea. Samples from North and South America suggest that H. zea is also a single species across its distribution. Our data reveal short genetic distances between H. armigera and H. zea which seem to have been established via a founder event from H. armigera stock at around 1.5 million years ago.

Conclusion
Our mitochondrial DNA sequence data supports the single species status of H. armigera across Africa, Asia and Australia. The evidence for inter-continental gene flow observed in this study is consistent with published evidence of the capacity of this species to migrate over long distances. The finding of high genetic similarity between Old World H. armigera and New World H. zea emphasises the need to consider work on both pests when building pest management strategies for either.

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Mixed mode stationary phases utilize secondary retention mechanisms to add a dimensionality to the surface of high performance liquid chromatography (HPLC) adsorbents. This approach was used by several authors to improve the separation performance of single dimension separations. We explored the magnitude of these secondary interactions by performing an off-line two-dimensional (2D)-HPLC separation with a Scherzo SM-C18 column of a β-lactoglobulin tryptic digest with a mobile phase pH of 7 in the first dimension and 2 in the second. Mechanism divergence was determined using the peak capacity and a geometric approach to factor analysis, to measure the correlation. This separation was repeated with a C18 stationary phase as a control. It was found that the C18 column had a correlation coefficient of 0.784, smaller than the mixed mode column, 0.884. This indicated that the retention mechanisms of the C18 column were more divergent under these two pH environments than the mixed mode column. However, the SM-C18 still provided alternative selectivity of the peptides to that of the C18 and could be considered as a good alternative for further 2D-HPLC separations.

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This paper responds to the problem of how Practice-Based Research (PBR) can be usefully incorporated into a cross-disciplinary, Mixed Method project design, by considering a non-conventional use of the NVivo qualitative analysis software package. NVivo also proves valuable in maximising the creative-arts practice interdisciplinary potential within PBR itself. The ensuing discussion centres around Deakin University’s ‘Flows and Catchments’ research and teaching initiative.

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Efficient management of chronic diseases is critical in modern health care. We consider diabetes mellitus, and our ongoing goal is to examine how machine learning can deliver information for clinical efficiency. The challenge is to aggregate highly heterogeneous sources including demographics, diagnoses, pathologies and treatments, and extract similar groups so that care plans can be designed. To this end, we extend our recent model, the mixed-variate restricted Boltzmann machine (MV.RBM), as it seamlessly integrates multiple data types for each patient aggregated over time and outputs a homogeneous representation called "latent profile" that can be used for patient clustering, visualisation, disease correlation analysis and prediction. We demonstrate that the method outperforms all baselines on these tasks - the primary characteristics of patients in the same groups are able to be identified and the good result can be achieved for the diagnosis codes prediction.

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Building on a habitat mapping project completed in 2011, Deakin University was commissioned by Parks Victoria (PV) to apply the same methodology and ground-truth data to a second, more recent and higher resolution satellite image to create habitat maps for areas within the Corner Inlet and Nooramunga Marine and Coastal Park and Ramsar area. A ground-truth data set using in situ video and still photographs was used to develop and assess predictive models of benthic marine habitat distributions incorporating data from both RapidEye satellite imagery (corrected for atmospheric and water column effects by CSIRO) and LiDAR (Light Detection and Ranging) bathymetry. This report describes the results of the mapping effort as well as the methodology used to produce these habitat maps.

Overall accuracies of habitat classifications were good, with error rates similar to or better than the earlier classification (>73 % and kappa values > 0.58 for both study localities). The RapidEye classification failed to accurately detect Pyura and reef habitat classes at the Corner Inlet locality, possibly due to differences in spectral frequencies. For comparison, these categories were combined into a ‘non-seagrass’ category, similar to the one used at the Nooramunga locality in the original classification. Habitats predicted with highest accuracies differed from the earlier classification and were Posidonia in Corner Inlet (89%), and bare sediment (no-visible seagrass class) in Nooramunga (90%). In the Corner Inlet locality reef and Pyura habitat categories were not distinguishable in the repeated classification and so were combined with bare sediments. The majority of remaining classification errors were due to the misclassification of Zosteraceae as bare sediment and vice versa. Dominant habitats were the same as those from the 2011 classification with some differences in extent. For the Corner Inlet study locality the no-visible seagrass category remained the most extensive (9059 ha), followed by Posidonia (5,513 ha) and Zosteraceae (5,504 ha). In Nooramunga no-visible seagrass (6,294 ha), Zosteraceae (3,122 ha) and wet saltmarsh (1,562 ha) habitat classes were most dominant.

Change detection analyses between the 2009 and 2011 imagery were undertaken as part of this project, following the analyses presented in Monk et al. (2011) and incorporating error estimates from both classifications. These analyses indicated some shifts in classification between Posidonia and Zosteraceae as well as a general reduction in the area of Zosteraceae. Issues with classification of mixed beds were apparent, particularly in the main Posidonia bed at Nooramunga where a mosaic of Zosteraceae and Posidonia was seen that was not evident in the ALOS classification. Results of a reanalysis of the 1998-2009 change detection illustrating effects of binning of mixed beds is also provided as an appendix.

This work has been successful in providing baseline maps at an improved level of detail using a repeatable method meaning that any future changes in intertidal and shallow water marine habitats may be assessed in a consistent way with quantitative error assessments. In wider use, these maps should also allow improved conservation planning, advance fisheries and catchment management, and progress infrastructure planning to limit impacts on the Inlet environment.

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Objectives:
To report if there is a difference in costs from a societal perspective between adults receiving rehabilitation in an inpatient rehabilitation setting versus an alternative setting. If there are cost differences, to report whether opting for the least expensive program setting adversely affects patient outcomes.

Data Sources:
Electronic databases from the earliest possible date until May 2011. All languages were included.

Study Selection
Multiple reviewers identified randomized controlled trials with a full economic evaluation that compared adult inpatient rehabilitation with an alternative. There were 29 included trials with 6746 participants.

Data Extraction
Multiple observers extracted data independently. Trial appraisal included a risk of bias assessment and a checklist to report the strength of the economic evaluation.

Data Synthesis:
Results were synthesized using standardized mean differences (SMDs) and meta-analyses for the primary outcome of cost. The Grading of Recommendations Assessment, Development, and Evaluation was applied to assess for risk of bias across studies for meta-analyses. There was high-quality evidence that cost was significantly reduced for rehabilitation in the home versus inpatient rehabilitation in a meta-analysis of 732 patients poststroke (pooled SMD [δ]=−.28; 95% confidence interval [CI], −.47 to −.09), without compromise to patient outcomes. Results of individual trials in other patient groups (orthopedic, rheumatoid arthritis, and geriatric) receiving rehabilitation in the home or community were generally consistent with the meta-analysis. There was moderate quality evidence that cost was significantly reduced for inpatient rehabilitation (stroke unit) versus general acute care in a meta-analysis of 463 patients poststroke (δ=.31; 95% CI, .15–.48), with improvement to patient outcomes. These results were not replicated in 2 individual trials with a geriatric and a mixed cohort, where costs did not differ between general acute care and inpatient rehabilitation. Three of the 4 individual trials, inclusive of a stroke or orthopedic population, reported less cost for an intensive inpatient rehabilitation program compared with usual inpatient rehabilitation. Sensitivity analysis included a health service perspective and varied inflation rates with no change to the significant findings of the meta-analyses.

Conclusions:
Based on this systematic review and meta-analyses, a single rehabilitation service may not provide health economic benefits for all patient groups and situations. For some patients, inpatient rehabilitation may be the most cost-effective method of providing rehabilitation; yet, for other patients, rehabilitation in the home or community may be the most cost-effective model of care. To achieve cost-effective outcomes, the ideal combination of rehabilitation services and patient inclusion criteria, as well as further data for nonstroke populations, warrants further research.

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In this paper we propose a cross-sectional model of the determinants of asset price bubbles. Using 589 firms listed on the NYSE, we find conclusive evidence that trading volume and share price volatility have statistically significant effects on asset price bubbles. However, evidence from sector-based stocks is mixed. We find that for firms belonging to electricity, energy, financial, and banking sectors, and for the smallest size firms, trading volume has a statistically significant and positive effect on bubbles. We do not discover any robust evidence of a statistically significant effect of share price volatility on bubbles at the sector-level.

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Background:
To describe the frequency of mixed specifier as proposed in DSM-5 in bipolar I patients with manic episodes, and to evaluate the effect of mixed specifier on symptom severity and treatment outcome.

Methods:
This post-hoc analysis used proxies for DSM-5 mixed features specifier by using MADRS or PANSS items.

Results:
Of the 960 patients analysed, 34%, 18% and 4.3% of patients, respectively, had ≥3 depressive features with mild (score ≥1 for MADRS items and ≥2 for PANSS item), moderate (score ≥2 MADRS, ≥3 PANSS) and severe (score ≥3 MADRS, ≥4 PANSS) symptoms. In patients with ≥3 depressive features and independent of treatment: MADRS remission (score ≤12) rate decreased with increasing severity (61–43%) and YMRS remission (score ≤12) was similar for mild and moderate patients (36–37%), but higher for severe (54%). In asenapine-treated patients, the MADRS remission rate was stable regardless of baseline depressive symptom severity (range 64–67%), whereas remission decreased with increasing severity with olanzapine (63–38%) and placebo (49–25%). Reduction in YMRS was significantly greater for asenapine compared with placebo at day 2 across the 3 severity cut-offs and continued to decrease throughout the treatment period. The difference between olanzapine and placebo was statistically significant in mild and moderate patients.

Limitations:
Results are from post-hoc analyses.

Conclusions:
These analyses support the validity of proposed DSM-5 criteria. They confirm that depressive features are frequent in bipolar patients with manic episodes. With increasing baseline severity of depressive features, treatment outcome was poorer with olanzapine and placebo, but remained stable with asenapine.

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A highly sensitive and simple analytical method was developed for analyzing the binary mixed pesticides of prometryne and acetochlor in soil–water system by gas chromatography/mass spectrometry (GC/MS). The sample solution was first purified by C18 solid-phase extraction column, which was leached by acetone. The leachate was enriched to 1.0 mL by pressure blowing concentrator and then analyzed by GC/MS. The linear calibration curves were showed in the range of 1–15 μg/mL with a correlation coefficient of 0.9991. The average recoveries (n = 5) were between 95.3 and 115.7%, with relative standard deviations ranged from 1.71 and 7.95%. The limits of detection of Prometryne/Acetochlor were up to 0.06 and 0.17 μg/mL, respectively. This method provides a reliable approach to examine and evaluate the residues of prometryne and acetochlor in the soil–water system.

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Additions to the aggregate housing stock are a broad measure of the state of an economy and overall level of confidence in a particular region over a designated period. This is due to the direct and indirect effect (e.g. employment in the housing construction industry) upon on the local economy and is linked to the confidence of local households in the future direction of housing investment, the level of housing affordability by households as related to employment levels and the relationship between supply and demand in each region. Another consideration is the ability of the government to monitor and successfully intervene in the operation of the household market (e.g. mortgage interest rates) with the intent of restricting an over-supply situation which may take years to fully recover. The analysis in this section examines new housing commencements for Scotland, Australia, USA and Canada over an extended time period with the specific focus placed on the periods before, during and after the high profile global financial crisis in 2007-2008. The graph in Figure 1 was adapted from data sourced from The Scottish Government (2013) and covers the 15-year period between 1998 and 2012. With the exception of 1999 there were been relatively few years with substantial additions to the housing market. However, the effect of the GFC can clearly be observed post 2007 although by 2012 there was relatively change from the previous year.

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The teaching rhetorical structure of various academic genres has been recognized as a practical, pedagogical tool in both ESL and EFL academic settings. However, assigning a unitary structure for different fields of study might poses problems for novice writers. In this study, the rhetorical structure of 120 abstracts (ninety ‘masters’ theses and thirty ‘doctoral’ dissertations) from six disciplines were investigated. In this exploratory study, four rhetorical structures were found: IMRC/D, CARS, Mixed, and None (which means the texts lack any rhetorical structure). The conclusion is that nonnative speakers require more than grammatical knowledge at the clause level. They need to be familiarized with the discourse grammar with the functional tokens attached to it in order to be successful in their academic writing.

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In this paper we evaluate the intertemporal pricing performance of stock return determinants over the periods surrounding, and outside of, financial crises. The analysis focuses on the variables of size, book-to-market ratio, momentum, liquidity, and higher-order systematic co-moments. The evidence reveals that over non-crisis periods the market beta plays an important role in determining the cross-section of stock returns. Size, value, momentum, and liquidity also exhibit associations with the cross-section of stock returns. However, over crisis periods most of the variables we examined lose their explanatory power, suggesting that their usefulness is limited for investment purposes when financial markets experience crises. There is some evidence of coskewness pricing surrounding market crashes. Practitioners may consider coskewness over crisis periods.

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Through analysis of the dynamics between science and decision-making, we argue that diagnosing fit-for purpose approaches to linking science and decision-making may be possible. Such diagnosis should enable identification of appropriate processes, institutions, objects (e.g. tools, information products) and relationships that can facilitate outcomes. We begin the paper by unsettling the traditional constructions that science must distance itself from debates about values and what is at stake, and so from policy making. Then, drawing from mixed methods case studies in coastal South-eastern Australia, we describe how scientific research has had a bearing on decisions affecting society and the environment. These analyses suggest that the willingness and capacity of research organisations, programmes or projects to actively reflect on and participate in the evolution of the 'operating environment' for their research is integral to their ability to inform outcomes through science. © 2014 Elsevier Ltd.

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This paper describes an ePortfolio implementation strategy at Federation University Australia, Victoria (formerly the University of Ballarat). The authors combined a personal and practical viewpoint to elicit pitfalls, challenges, and recommendations for improvement. The paper is divided into three main areas in order to outline the experiments that occurred. The first section provides a standard literature review around ePortfolio adoption as well as a research-based analysis of available ePortfolio software at Australian universities. The second part depicts the University’s ePortfolio implementation strategy that focused on “test-to-production” and technology dissemination phases. This section is based on the authors’ personal viewpoint of ePortfolio adoption at a university where a “top-down management decision making model” (Slade, Murfin, & Readman, 2013, p. 178) was used. Third, the evaluation strategy is reported, which was based on similar research conducted at Australian universities (Hallam & Creagh, 2010; Hallam, Harper, Hauville, Creagh, & McAllister, 2009). This part is offered as a modest-scoped, mixed methods evaluation process. The paper extends on ePortfolio implementation strategies (Bell & White, 2013; Coffey & Ashford-Rowe, 2014; Jarrott & Gambrel, 2011; Lambert & Corrin, 2007; Ring & Ramirez, 2012; Slade et al., 2013) and software analysis (ACODE, 2011; Slade et al., 2013). Recommendations are made for the careful integration of pre- and post-rollout of ePortfolio programs with face-to-face ePortfolio tutor support, offering online resources and alternative portfolio-making options for students with poor broadband access.