165 resultados para journal ranking
Resumo:
Background: Transthoracic echocardiography (TTE) during extra corporeal membrane oxygenation (ECMO) is important but can be technically challenging. Contrast-specific TTE can improve imaging in suboptimal studies. These contrast microspheres are hydrodynamically labile structures. This study assessed the feasibility of contrast echocardiography (CE) during venovenous (VV) ECMO in a validated ovine model. Method: Twenty-four sheep were commenced on VV ECMO. Parasternal long-axis (Plax) and short-axis (Psax) views were obtained pre- and postcontrast while on VV ECMO. Endocardial definition scores (EDS) per segment were graded: 1 = good, 2 = suboptimal 3 = not seen. Endocardial border definition score index (EBDSI) was calculated for each view. Endocardial length (EL) in the Plax view for the left ventricle (LV) and right ventricle (RV) was measured. Results: Summation EDS data for the LV and RV for unenhanced TTE (UE) versus CE TTE imaging: EDS 1 = 289 versus 346, EDS 2 = 38 versus 10, EDS 3 = 33 versus 4, respectively. Wilcoxon matched-pairs rank-sign tests showed a significant ranking difference (improvement) pre- and postcontrast for the LV (P < 0.0001), RV (P < 0.0001) and combined ventricular data (P < 0.0001). EBDSI for CE TTE was significantly lower than UE TTE for the LV (1.05 ± 0.17 vs. 1.22 ± 0.38, P = 0.0004) and RV (1.06 ± 0.22 vs. 1.42 ± 0.47, P = 0.0.0006) respectively. Visualized EL was significantly longer in CE versus UE for both the LV (58.6 ± 11.0 mm vs. 47.4 ± 11.7 mm, P < 0.0001) and the RV (52.3 ± 8.6 mm vs. 36.0 ± 13.1 mm, P < 0.0001), respectively. Conclusions: Despite exposure to destructive hydrodynamic forces, CE is a feasible technique in an ovine ECMO model. CE results in significantly improved EDS and increased EL.
Resumo:
Purpose – Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that it is difficult to measure with accuracy. Various wear measuring techniques have been used where out-of-roundness was found to be the most reliable method of measuring small wear quantities in journal bearings. This technique was further developed to achieve higher accuracy in measuring small wear quantities. The method proved to be reliable as well as inexpensive. The paper aims to discuss these issues. Design/methodology/approach – In an experimental study, the effect of antiwear additives was studied on journal bearings lubricated with oil containing solid contaminants. The test duration was too long and the wear quantities achieved were too small. To minimise the test duration, short tests of about 90 min duration were conducted and wear was measured recording changes in variety of parameters related to weight, geometry and wear debris. The out-of-roundness was found to be the most effective method. This method was further refined by enlarging the out-of-roundness traces on a photocopier. The method was proved to be reliable and inexpensive. Findings – Study revealed that the most commonly used wear measurement techniques such as weight loss, roughness changes and change in particle count were not adequate for measuring small wear quantities in journal bearings. Out-of-roundness method with some refinements was found to be one of the most reliable methods for measuring small wear quantities in journal bearings working in hydrodynamic lubrication regime. By enlarging the out-of-roundness traces and determining the worn area of the bearing cross-section, weight loss in bearings was calculated, which was repeatable and reliable. Research limitations/implications – This research is a basic in nature where a rudimentary solution has been developed for measuring small wear quantities in rotary devices such as journal bearings. The method requires enlarging traces on a photocopier and determining the shape of the worn area on an out-of-roundness trace on a transparency, which is a simple but a crude method. This may require an automated procedure to determine the weight loss from the out-of-roundness traces directly. This method can be very useful in reducing test duration and measuring wear quantities with higher precision in situations where wear quantities are very small. Practical implications – This research provides a reliable method of measuring wear of circular geometry. The Talyrond equipment used for measuring the change in out-of-roundness due to wear of bearings indicates that this equipment has high potential to be used as a wear measuring device also. Measurement of weight loss from the traces is an enhanced capability of this equipment and this research may lead to the development of a modified version of Talyrond type of equipment for wear measurements in circular machine components. Originality/value – Wear measurement in hydrodynamic bearings requires long duration tests to achieve adequate wear quantities. Out-of-roundness is one of the geometrical parameters that changes with progression of wear in a circular shape components. Thus, out-of-roundness is found to be an effective wear measuring parameter that relates to change in geometry. Method of increasing the sensitivity and enlargement of out-of-roundness traces is original work through which area of worn cross-section can be determined and weight loss can be derived for materials of known density with higher precision.
Resumo:
Aim Determining how ecological processes vary across space is a major focus in ecology. Current methods that investigate such effects remain constrained by important limiting assumptions. Here we provide an extension to geographically weighted regression in which local regression and spatial weighting are used in combination. This method can be used to investigate non-stationarity and spatial-scale effects using any regression technique that can accommodate uneven weighting of observations, including machine learning. Innovation We extend the use of spatial weights to generalized linear models and boosted regression trees by using simulated data for which the results are known, and compare these local approaches with existing alternatives such as geographically weighted regression (GWR). The spatial weighting procedure (1) explained up to 80% deviance in simulated species richness, (2) optimized the normal distribution of model residuals when applied to generalized linear models versus GWR, and (3) detected nonlinear relationships and interactions between response variables and their predictors when applied to boosted regression trees. Predictor ranking changed with spatial scale, highlighting the scales at which different species–environment relationships need to be considered. Main conclusions GWR is useful for investigating spatially varying species–environment relationships. However, the use of local weights implemented in alternative modelling techniques can help detect nonlinear relationships and high-order interactions that were previously unassessed. Therefore, this method not only informs us how location and scale influence our perception of patterns and processes, it also offers a way to deal with different ecological interpretations that can emerge as different areas of spatial influence are considered during model fitting.
Resumo:
Aims/hypothesis Diabetic retinopathy is a serious complication of diabetes mellitus and can lead to blindness. A genetic component, in addition to traditional risk factors, has been well described although strong genetic factors have not yet been identified. Here, we aimed to identify novel genetic risk factors for sight-threatening diabetic retinopathy using a genome-wide association study. Methods Retinopathy was assessed in white Australians with type 2 diabetes mellitus. Genome-wide association analysis was conducted for comparison of cases of sight-threatening diabetic retinopathy (n = 336) with diabetic controls with no retinopathy (n = 508). Top ranking single nucleotide polymorphisms were typed in a type 2 diabetes replication cohort, a type 1 diabetes cohort and an Indian type 2 cohort. A mouse model of proliferative retinopathy was used to assess differential expression of the nearby candidate gene GRB2 by immunohistochemistry and quantitative western blot. Results The top ranked variant was rs3805931 with p = 2.66 × 10−7, but no association was found in the replication cohort. Only rs9896052 (p = 6.55 × 10−5) was associated with sight-threatening diabetic retinopathy in both the type 2 (p = 0.035) and the type 1 (p = 0.041) replication cohorts, as well as in the Indian cohort (p = 0.016). The study-wide meta-analysis reached genome-wide significance (p = 4.15 × 10−8). The GRB2 gene is located downstream of this variant and a mouse model of retinopathy showed increased GRB2 expression in the retina. Conclusions/interpretation Genetic variation near GRB2 on chromosome 17q25.1 is associated with sight-threatening diabetic retinopathy. Several genes in this region are promising candidates and in particular GRB2 is upregulated during retinal stress and neovascularisation.
Resumo:
Welcome to this special edition of the Journal of Learning Design which focuses on legal education and curriculum renewal in law. At the outset ,we would like to thank the editors of the Journal, Margaret Lloyd and Nan Bahr for agreeing to host this special edition. The special edition is timely as legal education in Australia is enjoying a lively period of renewal.
Resumo:
Document clustering is one of the prominent methods for mining important information from the vast amount of data available on the web. However, document clustering generally suffers from the curse of dimensionality. Providentially in high dimensional space, data points tend to be more concentrated in some areas of clusters. We take advantage of this phenomenon by introducing a novel concept of dynamic cluster representation named as loci. Clusters’ loci are efficiently calculated using documents’ ranking scores generated from a search engine. We propose a fast loci-based semi-supervised document clustering algorithm that uses clusters’ loci instead of conventional centroids for assigning documents to clusters. Empirical analysis on real-world datasets shows that the proposed method produces cluster solutions with promising quality and is substantially faster than several benchmarked centroid-based semi-supervised document clustering methods.
Resumo:
Commercial environments may receive only a fraction of expected genetic gains for growth rate as predicted from the selection environment This fraction is the result of undesirable genotype-by-environment interactions (G x E) and measured by the genetic correlation (r(g)) of growth between environments. Rapid estimates of genetic correlation achieved in one generation are notoriously difficult to estimate with precision. A new design is proposed where genetic correlations can be estimated by utilising artificial mating from cryopreserved semen and unfertilised eggs stripped from a single female. We compare a traditional phenotype analysis of growth to a threshold model where only the largest fish are genotyped for sire identification. The threshold model was robust to differences in family mortality differing up to 30%. The design is unique as it negates potential re-ranking of families caused by an interaction between common maternal environmental effects and growing environment. The design is suitable for rapid assessment of G x E over one generation with a true 0.70 genetic correlation yielding standard errors as low as 0.07. Different design scenarios were tested for bias and accuracy with a range of heritability values, number of half-sib families created, number of progeny within each full-sib family, number of fish genotyped, number of fish stocked, differing family survival rates and at various simulated genetic correlation levels
Resumo:
Nahhas, Wolfe, and Chen (2002, Biometrics 58, 964-971) considered optimal set size for ranked set sampling (RSS) with fixed operational costs. This framework can be very useful in practice to determine whether RSS is beneficial and to obtain the optimal set size that minimizes the variance of the population estimator for a fixed total cost. In this article, we propose a scheme of general RSS in which more than one observation can be taken from each ranked set. This is shown to be more cost-effective in some cases when the cost of ranking is not so small. We demonstrate using the example in Nahhas, Wolfe, and Chen (2002, Biometrics 58, 964-971), by taking two or more observations from one set even with the optimal set size from the RSS design can be more beneficial.
Resumo:
The music business is one of the most international of all the cultural industries. Music, industry practices, and people travel easily across country borders and the major music companies are dominating national music markets across the globe. However, at the same time the music industries in different countries are very idiosyncratic. Music is an ingrained part of a country’s history, its culture and heritage. One aspect of this idiosyncrasy is related to how creatives, audiences and music organizations are affected by and is able to take advantage of the ongoing digitization of society.
Resumo:
- Problem Climate change is affecting the world in numerous ways such as increased temperatures, sea level rise, and increased droughts and floods. Governments worldwide, especially in the most vulnerable countries, are urged to seek better solutions for sustainable development. The construction industry and buildings have enormous impacts on humans and the environment, meaning green building must be one of the solutions. Government involvement is widely considered as one of the essential and most effective ways to promote green building and drive the construction market towards sustainability. This paper will review green building policy of the Pacific-Rim countries that are most vulnerable to climate change according to the recent Standard and Poor’s ranking, including: Cambodia, Vietnam, Fiji, Philippines, Papua New Guinea and Indonesia. Methodology: This paper will review policy related publications including journal and conference papers, portal websites of governments, legislation documents and reports of international organisations. It will focus on the policies and governmental instruments that support the adoption of green building practices. - Findings All six governments have launched climate change adaptation policies, showing a great concern regarding the damages caused by the phenomenon. All countries except Papua New Guinea have promulgated energy efficiency policy and programs which indirectly promote the adoption of green building practices. The comparison study shows that Philippines and Indonesia motivate the adoption of renewable energy generation, energy efficiency and green building through either financial or advocacy instruments, while other four countries tend to implement regulatory tools to mandate energy conservation. Through comparison, Cambodia and Vietnam – the two countries providing vision to develop green building - can learn from Philippines and Indonesia’s policy and instruments. - Research limitations Language differences between the countries and limit of formal sources may pose difficulties in searching for information. While much English language literature exists, sources from Cambodia, Philippines and Indonesia are less accessible. - Takeaway for practice As the paper provides more understanding about the supportive policy of those countries, it will introduce more opportunities for green property developers to invest in construction markets of those Pacific-Rim countries. - Originality There is little research reviewing green building supportive policies of developing and less-wealthy countries that are forecasted to be most vulnerable and most impacted by climate change. The originality of this paper lies in its investigation on how those countries intend to respond to this phenomenon and whether and to what extent they support the green building market by using policy tools.
Resumo:
Public private partnerships (PPP) are widely used for construction project procurement. However, the briefing stage of PPP projects has been largely overlooked, although it has a far-reaching influence throughout the project life cycle. In response, we rectify this by exploring the critical factors involved. A set of 15 procurement-related factors are first identified from the existing literature. Then the effects of four background variables on the factors are tested with Hong Kong government data by an exploratory factor analysis extracting four major dimensions. The relationships between these dimensions and background variables indicate the need to take the background variables into account when ranking the factors. The ranking of the factors is then obtained by considering their weighted importance. Finally, the final practical value of the results is discussed.
Resumo:
We perceive the epistemological boundaries of Critical Indigenous Studies as marked by analyses of contemporary colonising power in its multiple forms in different contexts. This first issue brings together a diverse group of international Indigenous scholars who are politically and intellectually engaged in theorising from their respective standpoints as well as spatial and geographic locations. As such these essays enable dialogue across and within different colonial power contexts addressing epistemological ethical and methodological concerns within the broad field of Indigenous studies. In each essay a connecting theme is the need for intercultural and comparative work and to import Indigenous agency in the writing of history...
Resumo:
Over the past two decades neo liberalism has shaped global economic activity. The international reach of the current economic crisis propelled by the subprime mortgage meltdown in the United States has affected Indigenous communities in different ways to those whose investments were depleted by the Wall Street activities of an unregulated corporate and banking sector. Throughout this roller coaster economic ride the low socio-economic position of Indigenous peoples continued in Canada, the United States of America, New Zealand, Hawaii and Australia. The logic, or illogic of capital, failed to extend the boom of the economic upturn to Indigenous peoples, but is poised to extend the repercussions of the current downturn deep into Indigenous lives. The consistency of the Indigenous socio-economic position across these countries, even where treaties exist, indicates that the phenomenon is based on a shared Indigenous reality. In this special edition, the commonality in the way in which Indigenous people are engaged in and positioned by market forces and regulation by their respective nation states is proposed as one of the foundation plates of that Indigenous positioning...
Resumo:
This edition of the International Critical Indigenous Studies Journal, our second for 2009 takes alternative understandings as its theme. All four articles in this edition attend to citizenship and Indigenous sovereignty though in different ways...
Resumo:
The articles in this edition of the International Journal of Critical Indigenous Studies engage collectively with how different epistemologies and cultural values inform power relations in different locations, situations and contemporary contexts. As a group, these articles demonstrate, over varying facets, how meaning, communicative intent and interpretive effect are constitutive of power relations between Indigenous people and non Indigenous people. Jackie Grey discusses the labour of belonging as played out in a dispute over Indigenous fishing rights in a small New England town of Aquinnah, located on Noepe Island the traditional lands of the Wampanoag in the United States of America. She reveals the ways in which the jurisdiction of non Indigenous belonging operates discursively and materially to preclude Indigenous rights and self determination. Grey's analysis highlights the incommensurability of Indigenous and non Indigenous belonging that are played out in power relations born of colonisation.