919 resultados para Systematic Development


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In previous chapters of this volume, various authors describe the development of herbaceous legumes for pastures on clay soils in Queensland until about the 1980s. Emphasis is on the collection and evaluation of the genus Desmanthus, given its relatively recent addition to agriculture and considerable potential for providing useful pasture legumes for clay soils, particularly in the seasonally dry areas of northern Australia. Other genera are also discussed, including early assessments of herbaceous legumes that were later developed for clay soils (Clitoria, Macroptilium and Stylosanthes). This chapter provides a summary of the development of herbaceous legumes for clay soils in Queensland from these earlier assessments until present. Beef cattle farming is the principal agricultural enterprise in seasonally dry areas of northern Australia, including large areas of clay soils in Queensland. Sown and naturally occurring grasses provide the key feed resource, and the inclusion of sown legumes can significantly improve live-weight gain and reproductive performance per unit area. Queensland has been the centre of development for legumes for clay soils in tropical and subtropical areas of Australia, mostly through assessing and developing plants held in the Australian Tropical Forages Genetic Resource Collection (ATFGRC) (now a component of the Australia Pastures Genebank (APG)). The systematic appraisal of genetic material for clay soils was a focus of well-resourced government research up to the early to mid-1990s, but declined thereafter as sown pasture research teams were dismantled and funding to maintain the ATFGRC declined. Cultivar development is now conducted by small government, private enterprise and university research teams that collaborate where possible. In recent studies the use of experienced researcher knowledge and old plant evaluation sites has been particularly valuable for identifying potentially useful material. Cultivars for long- and short-term pastures on clay soils have been developed to the level of commercial seed production for Desmanthus (five cultivars from four species with two cultivars (one composite) in current use), Clitoria ternatea (one cultivar), Macroptilium bracteatum (two) and Stylosanthes seabrana (two). Other potential cultivars of these species are currently in various stages of development. Each species has different production niches depending on climate, clay soil type and grazing strategy. Adoption of these cultivars is occurring but has variously been impeded by limited promotion, mismatch of seed supply and demand, and difficulty establishing legumes in pastures of some key grass species. Recent renewed investment by the Australian Beef Industry has seen revived government research into pasture legumes in Queensland and rejuvenation of the APG.

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Background: Body composition is affected by diseases, and affects responses to medical treatments, dosage of medicines, etc., while an abnormal body composition contributes to the causation of many chronic diseases. While we have reliable biochemical tests for certain nutritional parameters of body composition, such as iron or iodine status, and we have harnessed nuclear physics to estimate the body’s content of trace elements, the very basic quantification of body fat content and muscle mass remains highly problematic. Both body fat and muscle mass are vitally important, as they have opposing influences on chronic disease, but they have seldom been estimated as part of population health surveillance. Instead, most national surveys have merely reported BMI and waist, or sometimes the waist/hip ratio; these indices are convenient but do not have any specific biological meaning. Anthropometry offers a practical and inexpensive method for muscle and fat estimation in clinical and epidemiological settings; however, its use is imperfect due to many limitations, such as a shortage of reference data, misuse of terminology, unclear assumptions, and the absence of properly validated anthropometric equations. To date, anthropometric methods are not sensitive enough to detect muscle and fat loss. Aims: The aim of this thesis is to estimate Adipose/fat and muscle mass in health disease and during weight loss through; 1. evaluating and critiquing the literature, to identify the best-published prediction equations for adipose/fat and muscle mass estimation; 2. to derive and validate adipose tissue and muscle mass prediction equations; and 3.to evaluate the prediction equations along with anthropometric indices and the best equations retrieved from the literature in health, metabolic illness and during weight loss. Methods: a Systematic review using Cochrane Review method was used for reviewing muscle mass estimation papers that used MRI as the reference method. Fat mass estimation papers were critically reviewed. Mixed ethnic, age and body mass data that underwent whole body magnetic resonance imaging to quantify adipose tissue and muscle mass (dependent variable) and anthropometry (independent variable) were used in the derivation/validation analysis. Multiple regression and Bland-Altman plot were applied to evaluate the prediction equations. To determine how well the equations identify metabolic illness, English and Scottish health surveys were studied. Statistical analysis using multiple regression and binary logistic regression were applied to assess model fit and associations. Also, populations were divided into quintiles and relative risk was analysed. Finally, the prediction equations were evaluated by applying them to a pilot study of 10 subjects who underwent whole-body MRI, anthropometric measurements and muscle strength before and after weight loss to determine how well the equations identify adipose/fat mass and muscle mass change. Results: The estimation of fat mass has serious problems. Despite advances in technology and science, prediction equations for the estimation of fat mass depend on limited historical reference data and remain dependent upon assumptions that have not yet been properly validated for different population groups. Muscle mass does not have the same conceptual problems; however, its measurement is still problematic and reference data are scarce. The derivation and validation analysis in this thesis was satisfactory, compared to prediction equations in the literature they were similar or even better. Applying the prediction equations in metabolic illness and during weight loss presented an understanding on how well the equations identify metabolic illness showing significant associations with diabetes, hypertension, HbA1c and blood pressure. And moderate to high correlations with MRI-measured adipose tissue and muscle mass before and after weight loss. Conclusion: Adipose tissue mass and to an extent muscle mass can now be estimated for many purposes as population or groups means. However, these equations must not be used for assessing fatness and categorising individuals. Further exploration in different populations and health surveys would be valuable.

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Background: Post-discharge mortality is a frequent but poorly recognized contributor to child mortality in resource limited countries. The identification of children at high risk for post-discharge mortality is a critically important first step in addressing this problem. Objectives: The objective of this project was to determine the variables most likely to be associated with post-discharge mortality which are to be included in a prediction modelling study. Methods: A two-round modified Delphi process was completed for the review of a priori selected variables and selection of new variables. Variables were evaluated on relevance according to (1) prediction (2) availability (3) cost and (4) time required for measurement. Participants included experts in a variety of relevant fields. Results: During the first round of the modified Delphi process, 23 experts evaluated 17 variables. Forty further variables were suggested and were reviewed during the second round by 12 experts. During the second round 16 additional variables were evaluated. Thirty unique variables were compiled for use in the prediction modelling study. Conclusion: A systematic approach was utilized to generate an optimal list of candidate predictor variables for the incorporation into a study on prediction of pediatric post-discharge mortality in a resource poor setting.

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Mechanistic models used for prediction should be parsimonious, as models which are over-parameterised may have poor predictive performance. Determining whether a model is parsimonious requires comparisons with alternative model formulations with differing levels of complexity. However, creating alternative formulations for large mechanistic models is often problematic, and usually time-consuming. Consequently, few are ever investigated. In this paper, we present an approach which rapidly generates reduced model formulations by replacing a model’s variables with constants. These reduced alternatives can be compared to the original model, using data based model selection criteria, to assist in the identification of potentially unnecessary model complexity, and thereby inform reformulation of the model. To illustrate the approach, we present its application to a published radiocaesium plant-uptake model, which predicts uptake on the basis of soil characteristics (e.g. pH, organic matter content, clay content). A total of 1024 reduced model formulations were generated, and ranked according to five model selection criteria: Residual Sum of Squares (RSS), AICc, BIC, MDL and ICOMP. The lowest scores for RSS and AICc occurred for the same reduced model in which pH dependent model components were replaced. The lowest scores for BIC, MDL and ICOMP occurred for a further reduced model in which model components related to the distinction between adsorption on clay and organic surfaces were replaced. Both these reduced models had a lower RSS for the parameterisation dataset than the original model. As a test of their predictive performance, the original model and the two reduced models outlined above were used to predict an independent dataset. The reduced models have lower prediction sums of squares than the original model, suggesting that the latter may be overfitted. The approach presented has the potential to inform model development by rapidly creating a class of alternative model formulations, which can be compared.

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Background Systematic reviews followed by ameta-analysis are carried out in medical research to combine the results of two or more related studies. Stroke trials have struggled to show beneficial effects and meta-analysis should be used more widely throughout the research process to either speed up the development of useful interventions, or halt more quickly research with hazardous or ineffective interventions. Summary of review. This review summarises the clinical research process and illustrates how and when systematic reviews may be used throughout the development programme. Meta-analyses should be performed after observational studies, preclinical studies in experimental stroke, and after phase I, II, and III clinical trials and phase IV clinical surveillance studies. Although meta-analyses most commonly work with summary data, they may be performed to assess relationships between variables (meta-regression) and, ideally, should utilise individual patient data. Meta-analysis techniques may alsoworkwith ordered categorical outcome data (ordinal meta-analysis) and be used to perform indirect comparisons where original trial data do not exist. Conclusion Systematic review/meta-analyses are powerful tools in medical research and should be used throughout the development of all stroke and other interventions

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The fruit is one of the most complex and important structures produced by flowering plants, and understanding the development and maturation process of fruits in different angiosperm species with diverse fruit structures is of immense interest. In the work presented here, molecular genetics and genomic analysis are used to explore the processes that form the fruit in two species: The model organism Arabidopsis and the diploid strawberry Fragaria vesca. One important basic question concerns the molecular genetic basis of fruit patterning. A long-standing model of Arabidopsis fruit (the gynoecium) patterning holds that auxin produced at the apex diffuses downward, forming a gradient that provides apical-basal positional information to specify different tissue types along the gynoecium’s length. The proposed gradient, however, has never been observed and the model appears inconsistent with a number of observations. I present a new, alternative model, wherein auxin acts to establish the adaxial-abaxial domains of the carpel primordia, which then ensures proper development of the final gynoecium. A second project utilizes genomics to identify genes that regulate fruit color by analyzing the genome sequences of Fragaria vesca, a species of wild strawberry. Shared and distinct SNPs among three F. vesca accessions were identified, providing a foundation for locating candidate mutations underlying phenotypic variations among different F. vesca accessions. Through systematic analysis of relevant SNP variants, a candidate SNP in FveMYB10 was identified that may underlie the fruit color in the yellow-fruited accessions, which was subsequently confirmed by functional assays. Our lab has previously generated extensive RNA-sequencing data that depict genome-scale gene expression profiles in F. vesca fruit and flower tissues at different developmental stages. To enhance the accessibility of this dataset, the web-based eFP software was adapted for this dataset, allowing visualization of gene expression in any tissues by user-initiated queries. Together, this thesis work proposes a well-supported new model of fruit patterning in Arabidopsis and provides further resources for F. vesca, including genome-wide variant lists and the ability to visualize gene expression. This work will facilitate future work linking traits of economic importance to specific genes and gaining novel insights into fruit patterning and development.

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Doutoramento em Engenharia do Ambiente - Instituto Superior de Agronomia - UL

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This dissertation aimed to investigate the development of motor competence in childhood and adolescence. As a starting point, a systematic review was conducted to investigate the instruments used for the evaluation of motor competence. This review identified a gap in the literature regarding the existence of an instrument to assess motor competence based on the three theoretical constructs (stability, locomotor, manipulative). In an attempt to fill this gap, a valid quantitative instrument was proposed. To meet this purpose, 584 children, between 6 and 14 years of age, were evaluated in nine motor tasks, three for each construct. The final instrument comprised two motor tasks for each construct (stability, locomotor, manipulative) and presented very good fit indexes. This instrument was used to analyse the motor competence behaviour by gender in different age groups, indicating that generally boys outperformed girls and both genders increased their performance across age groups. However, different motor competence growth rates appear in both genders across age groups. In addition, children with high and low motor competence were compared regarding some of their health related fitness variables. We found that, regardless of age and gender, the group with better motor proficiency always showed better results in health related fitness. We found positive moderate to high correlations between motor competence and the variables of cardiovascular fitness and muscular fitness, and an inverse correlation with body composition across the four age groups. We also found that motor competence explained 75% of the variance of the health related fitness for the total sample, with locomotion as the primary predictor. However, when analysing the four age groups, stability skills seem to play an important role in health related fitness in the transition from childhood to adolescence. In conclusion, educational and health policies should consider the development of motor competence as an essential strategy to promote healthy development throughout life.

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Antecedentes: El chocolate tiene propiedades especiales que ayudan a proteger el cuerpo humano de enfermedades cardiovasculares, incrementa el colesterol HDL y reduce la presión sanguínea. El consumo de chocolate también ayuda a reducir el estrés, eleva el ´animo y reduce el cansancio. El propósito de esta revisión es identificar, seleccionar, organizar y resumir estudios que investiguen el chocolate en relación con la salud, las características sensoriales y las actitudes de las personas. Este artículo es parte de la tesis de maestría: Is there a need for “healthy” chocolate? Systematic literature review and consumer research in Belgium and in Denmark (Es necesario el chocolate “saludable”? Revisión sistemática de la literatura y estudio al consumidor en Bélgica y Dinamarca), presentada por la autora en Junio del 2015 a la Universidad de Aalborg en Copenhague. Métodos: Este estudio presenta tres áreas relacionadas con el chocolate: Chocolate y su relación con la salud; características sensoriales y aceptación del chocolate; y actitudes hacia el chocolate. Una revisión sistemática de la literatura fue realizada para identificar, seleccionar, organizar y resumir estudios que investiguen al chocolate en relación con estas tres áreas. Cuatro bases de datos fueron escogidas: PubMed, Science Direct, Scopus y Web of Science por sus extensiones y porque superponen investigaciones interdisciplinarias.Resultados: Se obtuvieron un total de 2062 hits en las cuatro bases de datos. Un total de sesenta artículos cumplieron los criterios y fueron identificados como relevantes. Los artículos fueron clasificados de acuerdo a las tres áreas incluidas en el estudio. En relación a la salud, se ha indicado en muchos estudios que los polifenoles en el chocolate pueden mejorar la salud, especialmente en enfermedades cardiovasculares. De acuerdo a las características sensoriales y aceptación del chocolate, se ha dicho que la forma del chocolate tiene una influencia en la percepción del mismo. Los polifenoles causan astringencia y amargor al chocolate, haciéndolo no muy apetecido para los consumidores; sin embargo, por razones de salud, los polifenoles deben ser conservados. Acerca de las actitudes hacia el chocolate, hay muchos factores que llevan al deseo incontrolable de consumir chocolate. El chocolate es el alimento más apetecido en Norte América, éste influencia el estado anímico y crea una sensación de saciedad. Conclusión: Con base en esta revisión se puede concluir que un chocolate “saludable” puede ser parte de una dieta saludable, a la gente le gusta disfrutar del chocolate, mujeres más que hombres. La literatura respalda las propiedades saludables que tiene el consumo del chocolate, por esto es necesario trabajar en el desarrollo de productos de chocolate.

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It is suggested here that the ultimate accuracy of DFT methods arises from the type of hybridization scheme followed. This idea can be cast into a mathematical formulation utilizing an integrand connecting the noninteracting and the interacting particle system. We consider two previously developed models for it, dubbed as HYB0 and QIDH, and assess a large number of exchange-correlation functionals against the AE6, G2/148, and S22 reference data sets. An interesting consequence of these hybridization schemes is that the error bars, including the standard deviation, are found to markedly decrease with respect to the density-based (nonhybrid) case. This improvement is substantially better than variations due to the underlying density functional used. We thus finally hypothesize about the universal character of the HYB0 and QIDH models.

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Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2016-07-21 14:22:50.954

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The overarching aim of this thesis was to develop an intervention to support patient-centred prescribing in the context of multimorbidity in primary care. Methods A range of research methods were used to address different components of the Medical Research Council, UK (MRC) guidance on the development and evaluation of complex interventions in health care. The existing evidence on GPs’ perceptions of the management of multimorbidity was systematically reviewed. In qualitative interviews, chart-stimulated recall was used to explore the challenges experienced by GPs when prescribing for multimorbid patients. In a cross-sectional study, the psychosocial issues that complicate the management of multimorbidity were examined. To develop the complex intervention, the Behaviour Change Wheel (BCW) was used to integrate behavioural theory with the findings of these three studies. A feasibility study of the new intervention was then conducted with GPs. Results The systematic review revealed four domains of clinical practice where GPs experienced difficulties in multimorbidity. The qualitative interview study showed that GPs responded to these difficulties by ‘satisficing’. In multimorbid patients perceived as stable, GPs preferred to ‘maintain the status quo’ rather than actively change medications. In the cross-sectional study, the significant association between multimorbidity and negative psychosocial factors was shown. These findings informed the development of the ‘Multimorbidity Collaborative Medication Review and Decision-making’ (MY COMRADE) intervention. The intervention involves peer support: two GPs review the medications prescribed to a complex multimorbid patient together. In the feasibility study, GPs reported that the intervention was appropriate for the context of general practice; was widely applicable to their patients with multimorbidity; and recommendations for optimising medications arose from all collaborative reviews. Conclusion Applying theory to empirical data has led to an intervention that is implementable in clinical practice, and has the potential to positively change GPs’ behaviour in the management of medications for patients with multimorbidity.

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Background: Falls are common events in older people, which cause considerable morbidity and mortality. Non-pharmacological interventions are an important approach to prevent falls. There are a large number of systematic reviews of non-pharmacological interventions, whose evidence needs to be synthesized in order to facilitate evidence-based clinical decision making. Objectives: To systematically examine reviews and meta-analyses that evaluated non-pharmacological interventions to prevent falls in older adults in the community, care facilities and hospitals. Methods: We searched the electronic databases Pubmed, the Cochrane Database of Systematic Reviews, EMBASE, CINAHL, PsycINFO, PEDRO and TRIP from January 2009 to March 2015, for systematic reviews that included at least one comparative study, evaluating any non-pharmacological intervention, to prevent falls amongst older adults. The quality of the reviews was assessed using AMSTAR and ProFaNE taxonomy was used to organize the interventions. Results: Fifty-nine systematic reviews were identified which consisted of single, multiple and multi-factorial non-pharmacological interventions to prevent falls in older people. The most frequent ProFaNE defined interventions were exercises either alone or combined with other interventions, followed by environment/assistive technology interventions comprising environmental modifications, assistive and protective aids, staff education and vision assessment/correction. Knowledge was the third principle class of interventions as patient education. Exercise and multifactorial interventions were the most effective treatments to reduce falls in older adults, although not all types of exercise were equally effective in all subjects and in all settings. Effective exercise programs combined balance and strength training. Reviews with a higher AMSTAR score were more likely to contain more primary studies, to be updated and to perform meta-analysis. Conclusions: The aim of this overview of reviews of non-pharmacological interventions to prevent falls in older people in different settings, is to support clinicians and other healthcare workers with clinical decision-making by providing a comprehensive perspective of findings.

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Background: Alcohol is a leading cause of global suffering. Europe reports the uppermost volume of alcohol consumption in the world, with Ireland and the United Kingdom reporting the highest levels of binge drinking and drunkenness. Levels of consumption are elevated among university students. Thus, this literature review aims to summarise the current research on alcohol consumption among university students in the Republic of Ireland and the United Kingdom. Methods: MEDLINE, CINAHL, EMBASE and PsychInfo were systematically searched for literature from January 2002 until December 2014. Each database was searched using the following search pillars: alcohol, university student, Ireland or the United Kingdom and prevalence studies. Results: Two thousand one hundred twenty eight articles were retrieved from electronic database searching. These were title searched for relevance. 113 full texts were retrieved and assessed for eligibility. Of these, 29 articles were deemed to meet inclusion criteria for the review. Almost two thirds of students reported a hazardous alcohol consumption score on the AUDIT scale. Over 20 % reported alcohol problems over their lifetime using CAGE while over 20 % exceed sensible limits each week. Noteworthy is the narrowing of the gender gap throughout the past decade. Conclusion: This is the first review to investigate consumption patterns of university students in Ireland and the United Kingdom. A range of sampling strategies and screening tools are employed in alcohol research which preclude comparability. The current review provides an overview of consumption patterns to guide policy development.

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The overall aim was to investigate the quality of palliative care from the patient perspective, to adapt and psychometrically evaluate the Quality from Patients’ Perspective instrument specific to palliative care (QPP-PC) and investigate the relationship between the combination of person- and organization-related conditions and patients’ perceptions of care quality. Methods: In the systematic literature review (I), 23 studies from 6 databases and reference lists in 2014 were synthesized by integrative thematic analysis. The quantitative studies (II–IV) had cross-sectional designs including 191 patients (73% RR) from hospice inpatient care, hospice day care, palliative units in nursing homes and home care in 2013–2014. A modified version of QPP was used. Additionally, person- and organization-related conditions were assessed. Psychometric evaluation, descriptive and inferential statistics were used. Main findings: Patients’ preferences for palliative care included living a meaningful life and responsive healthcare personnel, care environment and organization of care (I). The QPP-PC was developed, comprising 12 factors (49 items), 3 single items and 4 dimensions: medical–technical competence, physical–technical conditions, identity–oriented approach, and socio-cultural atmosphere (II). QPP-PC measured patients’ perceived reality (PR) and subjective importance (SI) of care quality. PR differed across settings, but SI did not (III). All settings exhibited areas of strength and for improvement (II, III). Person-related conditions seemed to be related to SI, and person- and organization-related conditions to PR, explaining 18–30 and 22-29% respectively of the variance (IV). Conclusions: The patient perspective of care quality (SI and PR) should be integrated into daily care and improvement initiatives in palliative care. The QPP-PC can measure patients’ perceptions of care quality. Registered nurses and other healthcare personnel need awareness of person- and organization-related conditions to provide high-quality person-centred care.