1000 resultados para sample range


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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670 p. Capítulos de introducción, metodología, discusión y conclusiones en castellano e inglés.

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Terahertz pulse imaging (TPI) is a novel noncontact, nondestructive technique for the examination of cultural heritage artifacts. It has the advantage of broadband spectral range, time-of-flight depth resolution, and penetration through optically opaque materials. Fiber-coupled, portable, time-domain terahertz systems have enabled this technique to move out of the laboratory and into the field. Much like the rings of a tree, stratified architectural materials give the chronology of their environmental and aesthetic history. This work concentrates on laboratory models of stratified mosaics and fresco paintings, specimens extracted from a neolithic excavation site in Catalhoyuk, Turkey, and specimens measured at the medieval Eglise de Saint Jean-Baptiste in Vif, France. Preparatory spectroscopic studies of various composite materials, including lime, gypsum and clay plasters are presented to enhance the interpretation of results and with the intent to aid future computer simulations of the TPI of stratified architectural material. The breadth of the sample range is a demonstration of the cultural demand and public interest in the life history of buildings. The results are an illustration of the potential role of TPI in providing both a chronological history of buildings and in the visualization of obscured wall paintings and mosaics.

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Lectrides varians (Mosely) is a large, ecologically-important, caddisfly found in perennial and intermittent streams throughout much of eastern Australia. We conducted a population genetic analysis to investigate the dispersal potential of L. varians, building on previous works that have assessed life-history traits associated with drought resistance. Genetic analyses of L. varians from the Grampians region of Victoria, based on mitochondrial DNA sequence data, revealed extensive gene flow and a lack of genetic structure across the sample range (ΦST = 0.04). This suggests that the species is a strong disperser and is likely to be resilient to increased drying and habitat fragmentation under climate change considering other known resistance traits. However, during this study, two divergent genotypes were identified, indicating a potential species complex. A comprehensive phylogenetic analysis of L. varians across its current range was subsequently performed, confirming the species is indeed paraphyletic, consisting of one lineage that is restricted to the Grampians National Park and the other being widespread throughout south-eastern Australia. Further analyses revealed consistent morphological differences between these lineages supporting the notion that L. varians is a species complex. We discuss the implications of these findings with regard to conservation and taxonomy of this important invertebrate group.

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The aim of this study was to compare standard plaster models with their digital counterparts for the applicability of the Index of Complexity, Outcome, and Need (ICON). Generated study models of 30 randomly selected patients: 30 pre- (T(0)) and 30 post- (T(1)) treatment. Two examiners, calibrated in the ICON, scored the digital and plaster models. The overall ICON scores were evaluated for reliability and reproducibility using kappa statistics and reliability coefficients. The values for reliability of the total and weighted ICON scores were generally high for the T(0) sample (range 0.83-0.95) but less high for the T(1) sample (range 0.55-0.85). Differences in total ICON score between plaster and digital models resulted in mostly statistically insignificant values (P values ranging from 0.07 to 0.19), except for observer 1 in the T(1) sample. No statistically different values were found for the total ICON score on either plaster or digital models. ICON scores performed on computer-based models appear to be as accurate and reliable as ICON scores on plaster models.

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Late Cretaceous (Maastrichtian)-Quaternary summary biostratigraphies are presented for Ocean Drilling Program (ODP) Leg 189 Sites 1168 (West Tasmanian Margin), 1170 and 1171 (South Tasman Rise), and 1172 (East Tasman Plateau). The age models are calibrated to magnetostratigraphy and integrate both calcareous (planktonic foraminifers and nannofossils) and siliceous (diatoms and radiolarians) microfossil groups with organic walled microfossils (organic walled dinoflagellate cysts, or dinocysts). We also incorporate benthic oxygen isotope stratigraphies into the upper Quaternary parts of the age models for further control. The purpose of this paper is to provide a summary age-depth model for all deep-penetrating sites of Leg 189 incorporating updated shipboard biostratigraphic data with new information obtained during the 3 yr since the cruise. In this respect we provide a report of work to November 2003, not a final synthesis of the biomagnetostratigraphy of Leg 189, yet we present the most complete integrated age model for these sites at this time. Detailed information of the stratigraphy of individual fossil groups, paleomagnetism, and isotope data are presented elsewhere. Ongoing efforts aim toward further integration of age information for Leg 189 sites and will include an attempt to correlate zonation schemes for all the major microfossil groups and detailed correlation between all sites.

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A 10Be/9Be-based chronostratigraphy has been determined for ODP 181, Site 1121 sediment core, recovered from the foot of the Campbell Plateau, Southwest Pacific Ocean. This core was drilled through the Campbell 'skin drift' in ca. 4500 m water depth on the mid-western margin of the extensive Campbell Nodule Field, beneath the flow of the major cold-water Deep Western Boundary Current (DWBC). In the absence of detailed biostratigraphy, beryllium isotopes have provided essential time information to allow palaeo-environmental interpretation to be undertaken on the upper 7 m of the core. Measured 10Be/9Be ratios of sediment, and of ferromanganese nodules entrapped in the sediment, decrease systematically with depth in the core, in accordance with radioactive decay. However, the 10Be/9Be data diverge from ca. 3 m below the seafloor (mbsf) to the top of the core, giving rise to several possible geochronological models. The preferred model assumes that the measured 10Be/9Be ratios of the nodule rims reflect initial 10Be/9Be ratios equivalent to contemporary seawater, and that these can be used to derive the true age of the sediment where the nodules occur. The nodule rim ages can be then used to interpret the sediment 10Be/9Be data, which indicate an overall age to ca. 7 mbsf of ca. 17.5 Ma. The derived chronology is consistent with diatom biostratigraphy, which indicates an age of 2.2-3.6 Ma at 1 mbsf. Calculated sedimentation rates range from 8 to 95 cm m.y.**-1, with an overall rate to 7 mbsf of ca. 39 cm m.y.**-1. The lowest rates generally coincide with the occurrence of entrapped nodules, and reflect periods of increased bottom current flow causing net sediment loss. Growth rates of individual nodules decrease towards the top of the sediment core, similar to the observed decrease in growth rate from core to rim of seafloor nodules from the Campbell Nodule Field. This may be related to an overall increase in the vigour of the DWBC from ca. 10 Ma to the present.

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INTRODUCTION: Acute myeloid leukemia (AML) is a heterogeneous clonal disorder often associated with dismal overall survival. The clinical diversity of AML is reflected in the range of recurrent somatic mutations in several genes, many of which have a prognostic and therapeutic value. Targeted next-generation sequencing (NGS) of these genes has the potential for translation into clinical practice. In order to assess this potential, an inter-laboratory evaluation of a commercially available AML gene panel across three diagnostic centres in the UK and Ireland was performed.

METHODS: DNA from six AML patient samples was distributed to each centre and processed using a standardised workflow, including a common sequencing platform, sequencing chips and bioinformatics pipeline. A duplicate sample in each centre was run to assess inter- and intra-laboratory performance.

RESULTS: An average sample read depth of 2725X (range 629-5600) was achieved using six samples per chip, with some variability observed in the depth of coverage generated for individual samples and between centres. A total of 16 somatic mutations were detected in the six AML samples, with a mean of 2.7 mutations per sample (range 1-4) representing nine genes on the panel. 15/16 mutations were identified by all three centres. Allelic frequencies of the mutations ranged from 5.6 to 53.3 % (median 44.4 %), with a high level of concordance of these frequencies between centres, for mutations detected.

CONCLUSION: In this inter-laboratory comparison, a high concordance, reproducibility and robustness was demonstrated using a commercially available NGS AML gene panel and platform.

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High-resolution (R approximate to 40 000) echelle spectroscopic observations of 13 high-latitude early-type stars are presented. These stars comprise the final part of a complete magnitude range limited sample based on low-resolution spectroscopy of targets drawn from the Palomar-Green survey. The magnitude range under consideration is 13 less than or equal to B-PG less than or equal to 14.6, corresponding to an approximate distance limit for main-sequence B-type objects of 5 less than or equal to d less than or equal to 40 kpc. Three stars are found to be apparently normal, young stars, based on their positions on the (T-eff, log g) diagram, normal abundance patterns and relatively large projected rotational velocities. A further star, PG 1209+263, was found to belong to the chemically peculiar (CP) silicon star class of objects. The remainder are evolved subluminous stars lying on post- horizontal branch (post-HB) tracks, with the exception of PG 2120+062, which appears to be in a post-asymptotic giant branch evolutionary stage. For the young stars in the sample, we have derived distance and age estimates through comparison of the atmospheric parameters with recent theoretical evolutionary models. We discuss formation scenarios by comparing times-of- flight and evolutionary time-scales. It is found that all stars could have formed in the Galactic disc and been ejected from there soon after their birth, with the exception of PG 1209+263. The adopted proper motion is found to be a crucial factor in the kinematical analysis. We also present some number densities for young B-type halo stars, which indicate that they are extremely scarce objects.

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Background: Total immunoglobulin A in saliva (s-IgA) is normally assayed using an enzyme-linked immunosorbent assay. We have investigated methodological issues relating to the use of particle-enhanced nephelometric immunoassay (PENIA)
to measure s-IgA in whole unstimulated saliva and determine its reference range.

Methods: Whole unstimulated resting saliva was collected to determine sample stability (temperature, time, effect of a protease inhibitor), limit of quantitation (LOQ), assay precision and analytical variation. The reference range for 134 healthy adults was determined.

Results: Linearity was excellent (4–10.3 mg L21, P, 0.001; R2 ¼ 0.997) and without significant bias (mean of 20.7%). The lowest intra- and inter-analytical coefficients of variation were 1.8% and 7.5% and LOQ was 1.4 mg L21. The concentration of s-IgA is stable at room temperature for up to 6 h, at 48C for 48 h, at 248C for two weeks and at 2808C for up to 1.3 yr. There is no evidence that a protease inhibitor increases the stability or that repeated freeze–thawing cycles degrade sample quality. The reference ranges for s-IgA concentration, s-IgA secretion, s-IgA:albumin and s-IgA:osmolality were 15.9–414.5 mg L21, 7.2–234.9 mg min21, 0.4–19 and 0.6–8.9, respectively.

Conclusion:
Automated PENIA assay of s-IgA is precise and accurate. High stability of collected saliva samples and the ease and speed of the assay make this an ideal method for use in athletic and military training situations. The convenience of measuring albumin and IgA on the same analytical platform adds to the practicability of the test.

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It has been proposed that body image disturbance is a form of cognitive bias wherein schemas for self-relevant information guide the selective processing of appearancerelated information in the environment. This threatening information receives disproportionately more attention and memory, as measured by an Emotional Stroop and incidental recall task. The aim of this thesis was to expand the literature on cognitive processing biases in non-clinical males and females by incorporating a number of significant methodological refinements. To achieve this aim, three phases of research were conducted. The initial two phases of research provided preliminary data to inform the development of the main study. Phase One was a qualitative exploration of body image concerns amongst males and females recruited through the general community and from a university. Seventeen participants (eight male; nine female) provided information on their body image and what factors they saw as positively and negatively impacting on their self evaluations. The importance of self esteem, mood, health and fitness, and recognition of the social ideal were identified as key themes. These themes were incorporated as psycho-social measures and Stroop word stimuli in subsequent phases of the research. Phase Two involved the selection and testing of stimuli to be used in the Emotional Stroop task. Six experimental categories of words were developed that reflected a broad range of health and body image concerns for males and females. These categories were high and low calorie food words, positive and negative appearance words, negative emotion words, and physical activity words. Phase Three addressed the central aim of the project by examining cognitive biases for body image information in empirically defined sub-groups. A National sample of males (N = 55) and females (N = 144), recruited from the general community and universities, completed an Emotional Stroop task, incidental memory test, and a collection of psycho-social questionnaires. Sub-groups of body image disturbance were sought using a cluster analysis, which identified three sub-groups in males (Normal, Dissatisfied, and Athletic) and four sub-groups in females (Normal, Health Conscious, Dissatisfied, and Symptomatic). No differences were noted between the groups in selective attention, although time taken to colour name the words was associated with some of the psycho-social variables. Memory biases found across the whole sample for negative emotion, low calorie food, and negative appearance words were interpreted as reflecting the current focus on health and stigma against being unattractive. Collectively these results have expanded our understanding of processing biases in the general community by demonstrating that the processing biases are found within non-clinical samples and that not all processing biases are associated with negative functionality

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This study examined the psychometric properties of an expanded version of the Algase Wandering Scale (Version 2) (AWS-V2) in a cross-cultural sample. A cross-sectional survey design was used. Study subjects were 172 English-speaking persons with dementia (PWD) from long-term care facilities in the USA, Canada, and Australia. Two or more facility staff rated each subject on the AWS-V2. Demographic and cognitive data (MMSE) were also obtained. Staff provided information on their own knowledge of the subject and of dementia. Separate factor analyses on data from two samples of raters each explained greater than 66% of the variance in AWS-V2 scores and validated four (persistent walking, navigational deficit, eloping behavior, and shadowing) of five factors in the original scale. Items added to create the AWS-V2 strengthened the shadowing subscale, failed to improve the routinized walking subscale, and added a factor, attention shifting as compared to the original AWS. Evidence for validity was found in significant correlations and ANOVAs between the AWS-V2 and most subscales with a single item indicator of wandering and with the MMSE. Evidence of reliability was shown by internal consistency of the AWS-V2 (0.87, 0.88) and its subscales (range 0.88 to 0.66), with Kappa for individual items (17 of 27 greater than 0.4), and ANOVAs comparing ratings across rater groups (nurses, nurse aids, and other staff). Analyses support validity and reliability of the AWS-V2 overall and for persistent walking, spatial disorientation, and eloping behavior subscales. The AWS-V2 and its subscales are an appropriate way to measure wandering as conceptualized within the Need-driven Dementia-compromised Behavior Model in studies of English-speaking subjects. Suggestions for further strengthening the scale and for extending its use to clinical applications are described.

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Exercise offers the potential to improve circulation, wound healing outcomes, and functional and emotional wellbeing for adults experiencing venous leg ulceration. Individuals with chronic leg ulcers typically have multiple comorbidities such as arthritis, asthma, chronic obstructive airways disease, cardiac disease or neuromuscular disorders, which would also benefit from regular exercise. The aim of this review is to highlight the relationships between the calf muscle pump and venous return and range of ankle motion for adults with venous leg ulcers. The effect of exercise will also be considered in relation to the healing rates for adults experiencing venous leg ulceration. The findings suggest there is evidence that exercises which engage the calf muscle pump improve venous return. Ankle range of motion, which is crucial for complete activation of the calf muscle pump, can also be improved with simple, home-based exercise programs. However, observational studies still report that venous leg ulcer patients are less physically active than age-matched controls. Therefore, the behavioural reasons for not exercising must be considered. Only two studies, both underpowered, have assessed the effect of exercise on the healing rates of venous leg ulcers. In conclusion, exercise is feasible with this patient population. However, future studies with larger sample sizes are needed to provide stronger evidence to support the therapeutic benefit of exercise as an adjunct therapy in wound care.

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Reviews into teacher education and reform measures, such as implementing professional standards for teachers, are designed to raise the quality of education. Such reviews and reforms also target preservice teachers; hence universities examine their teacher education programs to address these issues, including developing programs that are current with the literature. Over the past fifteen years, concerns have arisen about Australian early adolescents and their disengagement from the schooling system, their “at risk” behaviour and their need for social, emotional and academic support. These concerns have prompted a middle schooling movement in Australia with the literature recognising a need for specialised middle school teachers. As a result, various universities have responded by developing courses specifically designed to graduate teachers who possess the theoretical and pedagogical knowledge for engaging early adolescent learners. This mixed-method study analysed the responses of preservice teachers from three universities across two states in Australia near the completion of their middle years teacher preparation program. The three aims of the study were to: (1) investigate final-year preservice teachers’ perceptions of their confidence to teach in the middle years of schooling; (2) analyse the experiences included in their teacher preparation course that made them feel confident; and (3) describe strategies for enhancing middle schooling teacher education preparation. Data were gathered from final-year preservice teachers (n=142) using a survey that was developed in response to middle schooling literature and the Professional Standards for Queensland Teachers (Queensland College of Teachers, 2006). A questionnaire collected extended information about the participants’ (n=142) experiences that made them feel confident. It also gathered information about strategies for enhancing middle years teacher preparation. One-to-one, 45-minute interviews (n=10) were conducted to elicit in-depth responses aligned with the research aims. Quantitative results indicated that the majority of preservice teachers (n=142) claimed confidence associated with survey items relating to creating a positive classroom environment (range: 70-97%), developing positive relationships for teaching (71-98%), pedagogical knowledge for teaching (72-95%), and implementation of teaching (70-91%). Qualitative findings suggested that the experiences that assisted them to be confident for teaching were practicum and associated field studies coursework, a positive mentor teacher, specifically designed middle years subjects, the pedagogical approaches of university staff, and other real-world experiences such as volunteering in schools and participating in professional development alongside their mentors. This study demonstrated that universities presenting middle years teacher preparation need to consider: the quality of the practicum experience; the suitability of mentor teachers; the significance and practicalities of middle years subjects; university lecturers’ modelling of pedagogical practices; and the inclusion of real-world learning experiences. Although the findings of this study provided evidence as to how preservice teacher confidence for teaching has been influenced by their middle schooling teacher preparation, further research is required to investigate how confidence translates into practice within their first years of teaching.