374 resultados para t-way testing


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Background Evolutionary biologists are often misled by convergence of morphology and this has been common in the study of bird evolution. However, the use of molecular data sets have their own problems and phylogenies based on short DNA sequences have the potential to mislead us too. The relationships among clades and timing of the evolution of modern birds (Neoaves) has not yet been well resolved. Evidence of convergence of morphology remain controversial. With six new bird mitochondrial genomes (hummingbird, swift, kagu, rail, flamingo and grebe) we test the proposed Metaves/Coronaves division within Neoaves and the parallel radiations in this primary avian clade. Results Our mitochondrial trees did not return the Metaves clade that had been proposed based on one nuclear intron sequence. We suggest that the high number of indels within the seventh intron of the β-fibrinogen gene at this phylogenetic level, which left a dataset with not a single site across the alignment shared by all taxa, resulted in artifacts during analysis. With respect to the overall avian tree, we find the flamingo and grebe are sister taxa and basal to the shorebirds (Charadriiformes). Using a novel site-stripping technique for noise-reduction we found this relationship to be stable. The hummingbird/swift clade is outside the large and very diverse group of raptors, shore and sea birds. Unexpectedly the kagu is not closely related to the rail in our analysis, but because neither the kagu nor the rail have close affinity to any taxa within this dataset of 41 birds, their placement is not yet resolved. Conclusion Our phylogenetic hypothesis based on 41 avian mitochondrial genomes (13,229 bp) rejects monophyly of seven Metaves species and we therefore conclude that the members of Metaves do not share a common evolutionary history within the Neoaves.

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This critical essay discusses the challenges and prospects for the reform of school-based literacy programs. It begins with an overview of the effects of a decade of test-driven accountability policy on research and teachers’ work, noting the continuing challenges of new demographics, cultures and technologies for literacy education. The case is made that whole school literacy programs can make a difference in improving the overall education of students and youth from low socioeconomic and cultural minority backgrounds. But this requires a strong emphasis on engagement with substantive readings of cultural, social and scientific worlds through talk, reading and writing. The key questions facing teachers, then, are not simply around basic skills instruction and acquisition, but about sustained, intellectually demanding and scaffolded talk around texts, print and multimodal.

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The globalized nature of modern society has generated a number of pressures that impact internationally on countries’ policies and practices of science education. Among these pressures are key issues of health and environment confronting global science, global economic control through multinational capitalism, comparative and competitive international testing of student science achievement, and the desire for more humane and secure international society. These are not all one-way pressures and there is evidence of both more conformity in the intentions and practices of science education and of a greater appreciation of how cultural differences, and the needs of students as future citizens can be met. Hence while a case for economic and competitive subservience of science education can be made, the evidence for such narrowing is countered by new initiatives that seek to broaden its vision and practices. The research community of science education has certainly widened internationally and this generates many healthy exchanges, although cultural styles of education other than Western ones are still insufficiently recognized. The dominance of English language within these research exchanges is, however, causing as many problems as it solves. Science education, like education as a whole, is a strongly cultural phenomenon, and this provides a healthy and robust buffer to the more negative effects of globalization

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Listening comprehension is the primary channel of learning a language. Yet of the four dominant macro-skills (listening, speaking, reading and writing), it is often difficult and inaccessible for second and foreign language learners due to its implicit process. The secondary skill, speaking, proceeds listening cognitively. Aural/oral skills precede the graphic skills, such as reading and writing, as they form the circle of language learning process. However, despite the significant relationship with other language skills, listening comprehension is treated lightly in the applied linguistics research. Half of our daily conversation and three quarters of classroom interaction are virtually devoted to listening comprehension. To examine the relationship of listening skill with other language skills, the outcome of 1800 Iranian participants undertaking International English Language Testing System (IELTS) in Tehran indicates the close correlation between listening comprehension and the overall language proficiency.

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Modern toxicology investigates a wide array of both old and new health hazards. Priority setting is needed to select agents for research from the plethora of exposure circumstances. The changing societies and a growing fraction of the aged have to be taken into consideration. A precise exposure assessment is of importance for risk estimation and regulation. Toxicology contributes to the exploration of pathomechanisms to specify the exposure metrics for risk estimation. Combined effects of co-existing agents are not yet sufficiently understood. Animal experiments allow a separate administration of agents which can not be disentangled by epidemiological means, but their value is limited for low exposure levels in many of today’s settings. As an experimental science, toxicology has to keep pace with the rapidly growing knowledge about the language of the genome and the changing paradigms in cancer development. During the pioneer era of assembling a working draft of the human genome, toxicogenomics has been developed. Gene and pathway complexity have to be considered when investigating gene–environment interactions. For a best conduct of studies, modern toxicology needs a close liaison with many other disciplines like epidemiology and bioinformatics.

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Purpose – This mixed-method study aims to determine the extent to which the career paths of senior managers conform with the traditional versus protean elements described in the careers literature and whether these paths vary by gender. Design/methodology/approach – A total of 15 senior managers (seven women and eight men) in a large public sector agency in Australia were interviewed about their career trajectories to date. Data were coded according to four major areas which characterise and distinguish between traditional and protean careers: development, orientation of the employee, definition of success, and organisational environment. A total of 81 managers (34 women and 47 men) from the same organisation were also surveyed. Variables of interest were those that could be triangulated with qualitative data such as the availability of career opportunities. Findings – Results suggest that, contrary to much existing literature which proposes that all careers have been fundamentally altered, the traditional career which relies on length of service, geographic mobility and a steady climb up the corporate ladder, is still the dominant model in some organisations. However, the trend towards protean careers is evident and is more pronounced for women than for men. Research limitations/implications – The specific nature of the organisation (large, male-dominated, public sector) may limit the generalisability of results. Practical implications – The framework used to explore career paths according to traditional/ protean elements in this study may assist human resource practitioners to develop appropriate strategies which maximise the professional development of employees. Originality/value – The results of this research challenge the universality of change in the nature of careers, particularly in public sector environments.

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Traditional recommendation methods offer items, that are inanimate and one way recommendation, to users. Emerging new applications such as online dating or job recruitments require reciprocal people-to-people recommendations that are animate and two-way recommendations. In this paper, we propose a reciprocal collaborative method based on the concepts of users' similarities and common neighbors. The dataset employed for the experiment is gathered from a real life online dating network. The proposed method is compared with baseline methods that use traditional collaborative algorithms. Results show the proposed method can achieve noticeably better performance than the baseline methods.

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Total hip arthroplasty (THA) has a proven clinical record for providing pain relief and return of function to patients with disabling arthritis. There are many successful options for femoral implant design and fixation. Cemented, polished, tapered femoral implants have been shown to have excellent results in national joint registries and long-term clinical series. These implants are usually 150mm long at their lateral aspect. Due to their length, these implants cannot always be offered to patients due to variations in femoral anatomy. Polished, tapered implants as short as 95mm exist, however their small proximal geometry (neck offset and body size) limit their use to smaller stature patients. There is a group of patients in which a shorter implant with a maintained proximal body size would be advantageous. There are also potential benefits to a shorter implant in standard patient populations such as reduced bone removal due to reduced reaming, favourable loading of the proximal femur, and the ability to revise into good proximal bone stock if required. These factors potentially make a shorter implant an option for all patient populations. The role of implant length in determining the stability of a cemented, polished, tapered femoral implant is not well defined by the literature. Before changes in implant design can be made, a better understanding of the role of each region in determining performance is required. The aim of the thesis was to describe how implant length affects the stability of a cemented, polished, tapered femoral implant. This has been determined through an extensive body of laboratory testing. The major findings are that for a given proximal body size, a reduction in implant length has no effect on the torsional stability of a polished, tapered design, while a small reduction in axial stability should be expected. These findings are important because the literature suggests that torsional stability is the major determinant of long-term clinical performance of a THA system. Furthermore, a polished, tapered design is known to be forgiving of cement-implant interface micromotion due to the favourable wear characteristics. Together these findings suggest that a shorter polished, tapered implant may be well tolerated. The effect of a change in implant length on the geometric characteristics of polished, tapered design were also determined and applied to the mechanical testing. Importantly, interface area does play a role in stability of the system; however it is the distribution of the interface and not the magnitude of the area that defines stability. Taper angle (at least in the range of angles seen in this work) was shown not to be a determinant of axial or torsional stability. A range of implants were tested, comparing variations in length, neck offset and indication (primary versus cement-in-cement revision). At their manufactured length, the 125mm implants were similar to their longer 150mm counterparts suggesting that they may be similarly well tolerated in the clinical environment. However, the slimmer cement-in-cement revision implant was shown to have a poorer mechanical performance, suggesting their use in higher demand patients may be hazardous. An implant length of 125mm has been shown to be quite stable and the results suggest that a further reduction to 100mm may be tolerated. However, further work is required. A shorter implant with maintained proximal body size would be useful for the group of patients who are unable to access the current standard length implants due to variations in femoral anatomy. Extending the findings further, the similar function with potential benefits of a shorter implant make their application to all patients appealing.

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This practice-led study explores different ways the subject of sustain-ability can be addressed within an Interactive Media Arts practice. The exploration encompasses three creative projects, Charmed, Distracted and e. Menura superba. Grounded in an ecological philosophy inspired by vegetarianism and the critical design philosophy of defuturing, the work shows how such a philosophical position can guide the redirection of practice. The concern for sustain-ability within my practice, and more generally the question of Interactive Media Arts and sustain-ability, I refer to as a problématique. The objective of this study is not one of finding an answer or a truth to an instrumentally posed question, but to explore the complexities of the problématique through a program of practice and intellectual investigation. The aim being to redirect my practice and to find a renewed raison d’être for practice through a process of opening up, encountering, and discovering otherwise unknown possibilities for practice. In the context of sustain-ability, this opening up of possibilities can be considered a form of futuring. A futuring I argue is only possible if the things we take for granted as integral aspects of our being, practices and life worlds, are revealed in ways that estrange them, rendering them visible in ways that allow questioning and change.

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Parents are at risk for inactivity; however, research into understanding parental physical activity (PA) is scarce. We integrated self-determined motivation, planning, and the theory of planned behavior (TPB) to better understand parental PA. Parents (252 mothers, 206 fathers) completed a main questionnaire assessing measures underpinning these constructs and a 1-week follow-up of PA behavior to examine whether self-determined motivation indirectly influenced intention via the TPB variables (i.e., attitude, subjective norm, and perceived behavioral control) and intention indirectly influenced behavior via planning. We found self-determined motivation on intention was fully mediated by the TPB variables and intention on behavior was partially mediated by the planning variables. In addition, slight differences in the model’s paths between the sexes were revealed. The results illustrate the range of important determinants of parental PA and provide support for the integrated model in explaining PA decision making as well as the importance of examining sex differences.

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This paper explores one of the ways in which the Somerset region in the United Kingdom, devastated by the foot and mouth epidemic in 2001, is trying to free itself from recurring negative representations and create more positive images of the area. After the epidemic projects were sought that would promote a more positive image and draw tourists back to the area. One of these projects drew on literary tourism to reinvigorate the site. A Walking and Bridle trail called the ‘Coleridge Way Walk’ has been implemented to take the images of the area from ones of disease and dirtiness to ones of Romantic longing. The Coleridge Way Walk uses past imaginings to re-energise the area. This energy, in part, comes from ‘re-imagining’ the site through past imaginings. The Coleridge Way Walk uses the past to create future direction for the once tainted area.

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Introduction: Delirium is a serious issue associated with high morbidity and mortality in older hospitalised people. Early recognition enables diagnosis and treatment of underlying cause/s, which can lead to improved patient outcomes. However, research shows knowledge and accurate nurse recognition of delirium and is poor and lack of education appears to be a key issue related to this problem. Thus, the purpose of this randomised controlled trial (RCT) was to evaluate, in a sample of registered nurses, the usability and effectiveness of a web-based learning site, designed using constructivist learning principles, to improve acute care nurse knowledge and recognition of delirium. Prior to undertaking the RCT preliminary phases involving; validation of vignettes, video-taping five of the validated vignettes, website development and pilot testing were completed. Methods: The cluster RCT involved consenting registered nurse participants (N = 175) from twelve clinical areas within three acute health care facilities in Queensland, Australia. Data were collected through a variety of measures and instruments. Primary outcomes were improved ability of nurses to recognise delirium using written validated vignettes and improved knowledge of delirium using a delirium knowledge questionnaire. The secondary outcomes were aimed at determining nurse satisfaction and usability of the website. Primary outcome measures were taken at baseline (T1), directly after the intervention (T2) and two months later (T3). The secondary outcomes were measured at T2 by participants in the intervention group. Following baseline data collection remaining participants were assigned to either the intervention (n=75) or control (n=72) group. Participants in the intervention group were given access to the learning intervention while the control group continued to work in their clinical area and at that time, did not receive access to the learning intervention. Data from the primary outcome measures were examined in mixed model analyses. Results: Overall, the effect of the online learning intervention over time comparing the intervention group and the control group were positive. The intervention groups‘ scores were higher and the change over time results were statistically significant [T3 and T1 (t=3.78 p=<0.001) and T2 and T1 baseline (t=5.83 p=<0.001)]. Statistically significant improvements were also seen for delirium recognition when comparing T2 and T1 results (t=2.58 p=0.012) between the control and intervention group but not for changes in delirium recognition scores between the two groups from T3 and T1 (t=1.80 p=0.074). The majority of the participants rated the website highly on the visual, functional and content elements. Additionally, nearly 80% of the participants liked the overall website features and there were self-reported improvements in delirium knowledge and recognition by the registered nurses in the intervention group. Discussion: Findings from this study support the concept that online learning is an effective and satisfying method of information delivery. Embedded within a constructivist learning environment the site produced a high level of satisfaction and usability for the registered nurse end-users. Additionally, the results showed that the website significantly improved delirium knowledge & recognition scores and the improvement in delirium knowledge was retained at a two month follow-up. Given the strong effect of the intervention the online delirium intervention should be utilised as a way of providing information to registered nurses. It is envisaged that this knowledge would lead to improved recognition of delirium as well as improvement in patient outcomes however; translation of this knowledge attainment into clinical practice was outside the scope of this study. A critical next step is demonstrating the effect of the intervention in changing clinical behaviour, and improving patient health outcomes.