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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Revisão sistemática do gênero Celeus Boie, 1831 (Aves: Piciformes: Picidae) / Systematic review of the genus Celeus Boie, 1831 (Aves: Piciformes: Picidae)

Firme, Daniel Honorato 15 January 2016 (has links)
O gênero Celeus compreende um número variável de espécies distribuídas por toda a região Neotropical. No que diz respeito à sistemática do gênero, poucas modificações taxonômicas foram feitas desde sua última grande revisão em 1982. Em relação às hipóteses de relacionamento das espécies incluídas no gênero, as poucas propostas disponíveis baseiam-se em dados moleculares, não existindo nenhuma baseada em dados morfológicos e bioacústicos. Dessa forma, os objetivos do presente estudo foram revisar a taxonomia do gênero Celeus, definir o número de espécies que o compõem, descrever eventuais variações morfológicas existentes nos táxons analisados e propor uma hipótese de relacionamento entre suas espécies, por meio da análise de caracteres morfológicos (plumagem, morfometria e osteologia) e vocais. Para isso foram analisados 1998 espécimes taxidermizados, 92 esqueletos e 200 arquivos sonoros testando sua aplicabilidade na sistemática do grupo, sob a ótica do conceito de espécie filogenética. Foi constatada a existência de uma grande variação individual nos caracteres de plumagem em praticamente todos os táxons analisados, o que provavelmente levou a descrições de várias espécies e subespécies, que demonstraram não ser válidas. Ao contrário dos caracteres de plumagem, os caracteres vocais demonstraram uma grande estabilidade, variando apenas entre as espécies. Os caracteres osteológicos também se mostraram úteis na sistemática de Celeus, apesar da grande variação individual observada. Ao final, C. obrieni, C. subflavus, C. tinnunculus, C. ochraceus e C. multifasciatus, antes tratadas como subespécies, foram validadas como espécies, além da inclusão de C. galeatus. O monofiletismo do gênero foi recuperado, corroborando estudos moleculares recentes, diferindo quanto ao posicionamento de C. galeatus em relação às demais espécies do gênero. Dentre os doze clados fortemente suportados, alguns corroboram os resultados das propostas moleculares disponíveis, como a relação de espécies-irmãs entre C. spectabilis e C. obrieni. Com a validação dessas cinco espécies e a confirmação do posicionamento de C. galeatus no gênero, Celeus passa a contar com 16 espécies (C. galeatus, C. spectabilis, C. obrieni, C. flavus, C. subflavus, C. loricatus, C. torquatus, C. tinnunculus, C. lugubris, C. flavescens, C. ochraceus, C. elegans, C. castaneus, C. grammicus, C. undatus e C. multifasciatus), o que representa um aumento de 62,5% no número de espécies segundo a última grande revisão taxonômica do gênero. / The genus Celeus encompasses a variable number of species distributed throughout the Neotropics. Regarding its systematic arrangement, few changes have been made since its lastest major review in 1982. As to its phylogenetic relationships, the few proposals available are based on molecular data, lacking a morphological and bioacustic hypothesis. Thus, the goals of this study were to conduct a taxonomic review of the genus Celeus, establish the number of species within it, describe any existing morphological variation in these taxa and propose a hypothesis of relationship among its species through the analysis of morphological characters (plumage, morphometry and osteology) and bioacustics. A total of 1998 study skins, 92 skeletons and 200 sound files were analyzed, testing its applicability in the systematics of the genus, under the perspective of the phylogenetic species concept. A great individual variation in plumage characters in almost all analyzed taxa has been verified. This variation may be seen as the reason that led former authors to describe many of the taxa here considered invalid. Unlike plumage, the vocal characters demonstrated a great stability, varying only between species. The osteological characters also proved its usefulness in the systematics of Celeus, despite its individual variation. Ultimately, C. obrieni, C. subflavus, C. tinnunculus, C. ochraceus and C. multifasciatus, taxa previously treated as subspecies, have been proved to be valid species. The monophyly of Celeus was recovered, as well as the placement of C. galeatus as a member of this genus, agreeing with recent molecular studies, but differing, as already remarked, in the placement of C. galeatus in respect to other species of the genus. Among the twelve strongly supported clades, some corroborate the results of the molecular studies available, such as the sister relationship between C. spectabilis and C. obrieni. The validation of these five taxa and the placement of C. galeatus in the genus, Celeus which now has 16 species (C. galeatus, C. spectabilis, C. obrieni, C. flavus, C. subflavus, C. loricatus, C. torquatus, C. tinnunculus, C. lugubris, C. flavescens, C. ochraceus, C. elegans, C. castaneus C. grammicus, C. undatus and C. multifasciatus), representing an increase of 62.5% in species number according to the latest major revision of the genus.
62

The effects of exercise-based interventions on repetitive autistic behaviors : A Systematic Literature Review

Ion, Andreea Diana January 2019 (has links)
Repetitive behaviors are a core symptom of autism spectrum disorders. They represent a major barrier to learning and social adaptation, affect levels of engagement in life situations, communication, social interactions and sustain social connections. Repetitive behaviors are often managed using exercise-based interventions which have been suggested to reduce repetitive behaviors and benefit mental health and behavioral functioning of individuals with ASD. The purpose of this systematic review was to explore and critically review the findings of previous studies examining effects of various exercise-based interventions on reducing autistic repetitive behaviors in children with autism spectrum disorder. Searches were limited to peer-reviewed studies written in English and published between Jan.2008- Jan. 2019. Only studies focusing on physical exercise-based interventions aiming to decrease repetitive behaviors as a symptom of an autistic spectrum disorder were included. Quality of articles included in the review was assessed using the Joanna Briggs checklists. Two researchers were involved in the quality assessment process, and any discrepancies were resolved through discussion. 5 studies were included in the final review. All studies examined the effects of short term exercise interventions on repetitive behaviors in children with ASD. There was no consistency across studies regarding types or duration of interventions, sample sizes or demographics of participants. However, the findings of the studies examined in this review provide a moderate to strong evidence that exercise-based interventions decrease repetitive behaviors. The studies reviewed included clinically relevant findings that can be used and adapted to fit different needs of children in future interventions. However, additional research using stronger and more varied designs, would be needed to determine the most beneficial types of exercise- based interventions for decreasing repetitive behaviors.
63

Influência dos fatores locais, sistêmicos e relativos ao cirurgião na osseointegração de implantes dentais: uma análise sistemática das evidências científicas / Influence of local, systemic and surgeon related factors in dental implants osseointegration

Daniel Isaac Sendyk 25 May 2017 (has links)
Os fatores que possam promover e incrementar a osseointegração, ou prejudicar o processo biológico, aumentando o índice de falhas, têm sido cada vez mais investigados com o objetivo de ampliar indicações e as taxas de sobrevivência dos implantes dentais assim como controlar fatores adversos. O objetivo desta tese foi identificar, analisar e sintetizar as evidências científicas quanto a influência das estatinas, do envelhecimento e da experiência do cirurgião no processo osseointegração e na sobrevivência de implantes dentais. Este volume apresenta um compilado de três revisões sistemáticas orientadas pelas recomendações PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). O processo de revisão foi realizado por meio de uma busca sistemática em cinco bases de dados eletrônicas (PubMed, Scopus, Web of Science, Embase e Cochrane Library), além de busca manual nas referências bibliográficas dos estudos incluídos. A meta-análise, quando cabível, foi realizada com o auxílio do software Review Manager (RevMan, Versão 5.3). O grau de heterogeneidade entre os estudos foi verificado por meio do teste Q de Cochran e I2. O viés das publicações foi avaliado com o auxílio das escalas Newcasttle-Ottawa e Cochrane Collaboration\'s Tool. A síntese dos dados permitiu a publicação de três artigos científicos dispostos nesta tese. / Factors that may promote and enhance osseointegration, or impair the biological process, have been increasingly investigated in order to expand the indications and survival rates of dental implants and control the adverse factors. The aim of this thesis is to identify and summarize the scientific evidence of statins, ageing and surgeon related factors that can influence osseointegration and survival of dental implants. This volume presents a compilation of three systematic reviews structured by PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The review process was carried out through a systematic search in five electronic databases (PubMed, Scopus, Web of Science, Embase and Cochrane Library) and bibliographical references of the included studies. Meta-analyses, when appropriate, were performed using the software Review Manager (RevMan version 5.3). The degree of heterogeneity in the studies was verified by Q Cochran test and I2. The bias of the publications was assessed with the assistance of Newcastle-Ottawa Scale and Cochrane Collaboration Tool\'s. The synthesis of the data was included in three papers prepared for this thesis.
64

Systematic review and meta-analysis of the effects of treatment and immunization against schistosomiasis

Fukushige, Mizuho January 2016 (has links)
Schistosomiasis is a water-borne parasitic disease of great public health importance mainly in sub-Saharan African countries. The majority of current control programmes use the antihelminthic drug praziquantel to reduce disease burden in endemic areas. Praziquantel treatment has been reported to accelerate the development of protective immunity against re-infection that otherwise takes years to develop. To date, there is no licensed vaccine for schistosomiasis in humans but an attenuated schistosome parasite vaccine has been tested in animal models. Employing systematic review and meta-analysis approaches, my PhD research has four main objectives relating to attenuated schistosome vaccine and praziquantel treatment: 1) to identify predictors that determine protection levels after treatment with attenuated Schistosoma mansoni vaccines in the mouse model, 2) to quantify the influence of host and schistosome parasite species on attenuated parasite vaccine efficacy, 3) to explore the direction of change (increase/decrease) in schistosome parasite-specific antibody isotypes after praziquantel treatment in humans, 4) to identify predictors of praziquantel efficacy in humans. My analyses revealed three factors that have an influence on the protection levels provided by attenuated schistosome parasite vaccines: increasing numbers of immunizing parasites had a positive effect on the levels of protection whereas increasing the radiation dose and the time to challenge infection had negative effects. Analyses showed that the attenuated schistosome vaccine has the potential to achieve protection levels as high as 79% after a single dose in mice. Alongside this, baboon studies consistently reported protective effects of attenuated schistosome vaccines against re-infection. These results show there is a high potential for an attenuated schistosome parasite vaccine to be effective in humans. A meta-analysis of the influence of praziquantel treatment on the direction of change in schistosome-specific antibody isotypes was conducted. The analysis revealed considerable variability in the antibodies’ direction of change among populations. The results also demonstrated an increase of anti-worm IgA and IgE in the majority of studies. These antibodies have been reported to have a protective effect against re-infection. The combination of age and infection intensity, and the number of days after treatment were identified as influential predictors for some antibody isotypes, but there was no single predictor that consistently affected all antibody isotypes in the same way. Praziquantel efficacy levels in humans were investigated and the analyses revealed that cure rates for schistosomiasis increase with praziquantel dose, and were affected by the identity of the schistosome parasite species (S. mansoni vs. S. haematobium) and the age of the participants (children: 0-19 years old vs. adults: ≥ 20 years old). There has been no clear efficacy level reduction over the treatment years (1979-2013) suggesting that praziquantel is still effective in the treatment of schistosomiasis despite concerns about possible resistance. The development of a schistosome vaccine will benefit from a closer investigation into the mechanisms through which protection is acquired in attenuated schistosome parasite vaccine studies showing high potential efficacy in animal models. Nevertheless, it will take time to develop a schistosome vaccine for human use. The uptake of the vaccine will be made even more challenging by the lack of adequate infrastructure in schistosomiasis endemic areas. In the meantime, close monitoring of praziquantel efficacy levels is necessary to confirm the effectiveness of schistosomiasis control in endemic areas.
65

Bone grafting and its effect on stablilty of the jaw on extraction patients: a systematic review

Megalaa, Alexmena R. 24 July 2018 (has links)
Tooth extraction is necessary when there is advanced decay, significance trauma or injury to the oral cavity, misalignment associated with crowded teeth or even, poor eruption of third molars. Typically, during extraction procedures, bone grafting material is inserted to minimize bone loss. Bone grafting has become a standard procedure in dentistry and an essential component in modern medicine. The practice started nearly 350 years ago when a Dutch doctor in 1668 performed the first and successful bone grafting operation. Currently, research studies are ongoing to enhance the success and viability of dental reconstruction. This thesis examines the effect of varying dental graft techniques and methodology on the stability and long-term effect on the jawbone. These techniques include five primary bone grafting methods, onlay, inlay, ridge expansion, distracted osteogenesis and guided bone regeneration (GBR) have been approved to enhance the outcome of dental implants. The review has presented the documented limitations and viability of each method. In this paper, the alternatives to bone grafting have also been elaborated. Based on the findings depicted in this research, the following recommendations will assist in achieving the best jawbone outcomes in long-term and short-term assessments. These recommendations are as follows, a proper evaluation of each patient to determine their health condition. The nature of the infection, injury, and trauma that led to the extraction of the tooth should be well documented. The selection of technique pertaining to dental restoration, functionality, and aesthetic needs are of primary factors considered. A proper clinical follow-up and monitoring of recovery process is an essential part that contributes to valid results. Finally, patient awareness is essential as well. The study found out that although some of the bone grafting techniques have shown a high survival rate, significant alveolar bone quality and quantity, and success of the implants, several reports that the use of bone grafts and implants is a practice that will still dominate dental surgery and attract more clinical assessments.
66

Psychological factors and psychological treatment for Cluster C personality disorders : a research portfolio

Honeyman, Victoria January 2015 (has links)
Background: There is a paucity of research into Cluster C personality disorders, however there is increasing recognition that they are highly prevalent, associated with significant distress and frequently present alongside co-occurring axis I disorders. Research has led to significant progress in the understanding of the psychological mechanisms and has guided the development of evidence based treatment for borderline personality disorder and therefore it is likely that increased focus on Cluster C personality disorders may lead to similar developments. This thesis aimed to examine and evaluate current research on psychological interventions for the treatment of Cluster C personality disorders. It also sought to explore psychological factors involved in the development and maintenance of cluster C personality disorder. Method: A systematic literature review examining the effectiveness of psychological treatments for cluster C personality disorder identified 16 studies. The empirical study recruited individuals identified by clinicians as meeting criteria for Cluster C personality disorders. Participants completed a range of self-report measures of personality psychopathology, interpersonal problems and axis I disorders and a series of interviews exploring adult attachment style, reflective function, autobiographical memories. These were completed at 2 time points, 4 months apart. Participants also provided responses to a semi-structured qualitative interview to gain insight into their beliefs about their difficulties. Additional information was also gained through participants’ psychiatric notes. Results: The systematic review results indicate that psychological interventions are effective in the treatment of cluster C personality disorders however studies generally focused on cognitive behavioural or psychodynamic approaches. There is a lack of clarity over which treatment components are most effective in treating particular features of cluster C personality disorders. The empirical paper identifies no significant changes in personality psychopathology, anxiety and depressive symptoms, interpersonal problems, reflective function and autobiographical memory across time. Participants demonstrated insecure adult attachment styles. Conclusions: Results from the systematic review and empirical study identify a need for more research to explore the complexity of personality psychopathology and co-occurring axis I and axis II disorders. It is also necessary for research to identify psychological factors involved in the development and maintenance of Cluster C personality disorders in order to guide evidence based treatments. The systematic review highlights the need for research to identify the most effective psychological treatments for cluster C personality disorders and to establish which components of treatment are most effective in targeting particular symptoms associated with cluster C personality disorder.
67

Does vitamin D supplementation alter plasma adipokines concentrations? A systematic review and meta-analysis of randomized controlled trials.

Dinca, Madalina, Serban, Maria-Corina, Sahebkar, Amirhossein, Mikhailidis, Dimitri P, Toth, Peter P, Martin, Seth S, Blaha, Michael J, Blüher, Matthias, Gurban, Camelia, Penson, Peter, Michos, Erin D, Hernandez, Adrian V., Jones, Steven R, Banach, Maciej 30 March 2016 (has links)
We aimed to elucidate the role of vitamin D supplementation on adipokines through a systematic review and a meta-analysis of randomized placebo-controlled trials (RCTs). The search included PUBMED, Scopus, Web of Science and Google Scholar through July 1st, 2015. Finally we identified 9 RCTs and 484 participants. Meta-analysis of data from 7 studies did not find a significant change in plasma adiponectin concentrations following vitamin D supplementation (mean difference [MD]: 4.45%, 95%CI: -3.04, 11.93, p=0.244; Q=2.18, I(2)=0%). In meta-regression, changes in plasma adiponectin concentrations following vitamin D supplementation were found to be independent of treatment duration (slope: 0.25; 95%CI: -0.69, 1.19; p=0.603) and changes in serum 25-hydroxy vitamin D [25(OH)D] levels (slope: -0.02; 95%CI: -0.15, 0.12; p=0.780). Meta-analysis of data from 6 studies did not find a significant change in plasma leptin concentrations following vitamin D supplementation (MD: -4.51%, 95%CI: -25.13, 16.11, p=0.668; Q=6.41, I(2)=21.97%). Sensitivity analysis showed that this effect size is sensitive to one of the studies; removing it resulted in a significant reduction in plasma leptin levels (MD: -12.81%, 95%CI: -24.33, -1.30, p=0.029). In meta-regression, changes in plasma leptin concentrations following vitamin D supplementation were found to be independent of treatment duration (slope: -1.93; 95%CI: -4.08, 0.23; p=0.080). However, changes in serum 25(OH)D were found to be significantly associated with changes in plasma leptin levels following vitamin D supplementation (slope: 1.05; 95%CI: 0.08, 2.02; p=0.033). In conclusion, current data did not indicate a significant effect of vitamin D supplementation on adiponectin and leptin levels. / Revisión por pares
68

Postnatal depression in African mothers

Gardner, Philippa January 2012 (has links)
Paper one is a systematic review aimed at improving our understanding of the culturally determined risk factors of postnatal depression (PND) within 'Sub-Saharan Africa', by integrating evidence from quantitative and qualitative studies. A mixed-method systematic review approach was employed, nine quantitative and three qualitative studies were quality assessed, synthesised, and integrated. Stressful life events, adhering to cultural values and traditions, the effects of negative cultural perceptions and difficulties within the African extended family system were found to be risk factors for the development and maintenance of PND in Sub-Saharan Africa. The objective of paper two was to explore the lived experience of postnatal depression in West African mothers living in the UK. A qualitative design using semi-structured interviews with six West African mothers (Nigeria = 3; Ghana = 3) who were experiencing low mood in the postnatal period was undertaken. Participants were recruited from mother and baby groups within the National Health Service. Interpretative Phenomenological Analysis was used to explore and analyse the data. Five overarching themes emerged: (1) conceptualiszing PND, (2) isolation, (3) loss of identity, (4) issues of trust and (5) relationships as a protective factor. Each theme consisted of a number of subthemes. Women exhibited symptoms of PND but did not regard it as an illness, with the name 'depression'. They viewed their emotional distress as a result of social stress, and described feelings of isolation, loss of identity and relationship difficulties. Women's cultural background influenced their help-seeking behaviour; participants often avoided talking about their feelings and kept their distress to themselves. The findings have clinical implications in how services should be designed to meet the needs of African communities. Paper three reflects on the process of developing culturally competent research through the development of the current thesis. Suggestions for future research and reflections on the strengths and limitations of the research process are embedded throughout. Clinical implications are discussed with reference to a community psychology model.
69

Is mentalising ability associated with mental health difficulties in adolescents? : a systematic review ; Understanding the construct of mentalising in adolescence and its association with mental health : a structural equation model

Battersby, Shona January 2018 (has links)
Mentalising is an "imaginative mental activity that enables us to perceive and interpret human behaviour in terms of internal mental states (e.g. needs, desires, feelings, beliefs, goals, purposes and reasons)" (Bateman & Fonagy, 2012; page 4). While this has been studied within an adult population, there has been a lack of research in understanding this construct in adolescence and its associations with mental health. This thesis aimed to systematically review the literature to establish if there was an association between mentalising difficulties and mental health disorders in adolescence. It further aimed to empirically investigate using a questionnaire-based study with adolescents, the constructs of mentalising and their associations with mental wellbeing. The review found a negative association, indicating that low mentalising skills were a risk factor for mental health difficulties. However, there was a lack of research in this area and methodological and conceptual concerns about the measurement of mentalising. The empirical study found that the theoretical model of mentalising did not fit for adolescents. This was discussed in relation to the need for further adolescent specific research to understand this developing construct. In addition, a refined model that was hypothesised to be 'self-awareness' was suggested that was found to predict the mental wellbeing outcomes, indicating a potential risk factor for mental health difficulties in adolescence.
70

Service engagement in psychosis : the role of psychological variables

Reid, Caroline January 2018 (has links)
INTRODUCTION: In psychosis, low engagement with mental health services is both prevalent and frequently associated with negative outcome. The overarching objective of this thesis was to investigate the role of psychological variables in service engagement in people with psychosis. A systematic review was conducted to examine the evidence for clinical and psychological correlates of engagement. An empirical study sought to investigate the association between engagement and psychological variables of a relational nature (i.e. mentalizing and interpersonal functioning). METHODS: A systematic search strategy across four electronic databases yielded seventeen journal articles. For the empirical study, forty-two people with multiple-episode psychosis completed self-report measures of service engagement, symptoms, mentalizing and interpersonal functioning, within a cross-sectional design. RESULTS: The review found relatively robust evidence supporting the association between engagement and numerous clinical variables. Eleven psychological variables were revealed as significant correlates of service engagement, encompassing developmental, individual and relational factors. Assessment of quality and risk of bias highlighted a number of limitations within included studies. In the empirical study, greater cognitive/disorganization symptomology was predictive of lower service engagement. Service engagement was significantly correlated with mentalizing, but not with interpersonal functioning. The relationship between cognitive/disorganized symptomology and engagement was not mediated by mentalizing performance. CONCLUSION: Numerous psychological variables are associated with service engagement, which has the potential to inform clinical practice in view of enhancing engagement. Qualitative and longitudinal studies with both service user and provider samples are required to capture the contextual information surrounding fluctuations in levels of engagement.

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