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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.
31

Radar multi-temporal and multi-sensor approach to characterise peat moorland burn scars and assess burn scar persistence in the landscape

Millin-Chalabi, Gail Rebecca January 2016 (has links)
Peat moorlands represent a nationally significant carbon store. Wildfires in peat moorlands release CO2 into the atmosphere, reducing the carbon store and burn into the seed bank preventing vegetation recovery. Burned areas of bare peat remain, known as ‘burn scars’ which are eroded by freeze thaw and desiccation, then weathered by precipitation and wind to cause discolouration of the water supply. A technique for the systematic monitoring of peat moorland burn scars is essential for informing land management and moorland restoration. Satellite data enables peat moorland burn scars to be monitored at the landscape scale for operational services e.g. European Forest Fire Information System (EFFIS). However, in the UK cloud is highly problematic for optical satellites and thermal data provides only a short window of opportunity for active fire detection. This thesis provides a unique line of enquiry by exploring the potential of Synthetic Aperture Radar (SAR) intensity and Interferometric Synthetic Aperture Radar (InSAR) coherence for burn scar characterisation and persistence, using a multi-temporal and multi-sensor approach for degraded peat moorland. The Peak District National Park (PDNP) was selected because it is a marginal moorland environment, which experiences high rates of peat erosion and will experience more wildfires, based on future projections of increased temperature, due to global warming. Initial SAR intensity results for the Bleaklow 2003 burn scar showed a clear post-fire increase of 7 dB for burned peat bog when acquired under wet conditions. Post-fire, dry − wet InSAR pairs were characterised by vegetation removal caused by combustion within the burn scar area, whereas wet − wet InSAR pairs characterised the burn scar, but also degraded peat moorland caused by previous wildfires blurring the new burn scar perimeter. Intensity differed significantly with slope for the PDNP 2003 wildfires, reducing the effectiveness of the technique for characterising burn scars on slopes facing away from the sensor, although these wildfires showed no significant difference on coherence for the inland bare ground class. When using coherence as a burn scar discriminator, this research found that it is essential to acquire InSAR pairs immediately post-fire with B⊥ < 550 m. Using a combination of intensity and coherence data a multi-difference colour composite was produced and an ISODATA classification applied. Results were reclassified to produce a burned area map with an overall map accuracy of 94% and Kappa Coefficient of 0.69 covering the Bleaklow and Kinder 2003 burn scars. Burn scars < 6 km2 provided a persistently higher burned area intensity signal for up to six months after the wildfire but only 2 − 3 months for coherence. The smaller Edale burn scar (0.10 km2) was characterised by 2 − 3 dB greater intensity for the burned area over a year after the wildfire. The Edale 2008 case study showed that L-band PALSAR data is less sensitive to characterising peat moorland burn scars compared to C-band data. This study therefore strongly recommends C-band data for peat moorland burn scar characterisation and monitoring. Future research will explore the new C-band Sentinel-1 data which offers improved spatial resolution and repeat-pass time.
32

Written in scars : stories of recovery from self harm

Shaverin, Lisa January 2013 (has links)
This study sought to hear the narratives of individuals that have recovered from self-harming, with the intention of bearing witness to both the narratives and remaining scars in order to better understand and inform clinical practice. A purposive sample of seven individuals was recruited. Participants were asked to photograph their scars and bring them to an interview. Narratives were generated and explored through a relatively unstructured individual interview. Both the images and narratives were analysed using a narrative approach exploring content, performance and structural aspects, emphasising researcher reflexivity throughout. Findings were understood through psychoanalytic theory and highlighted a theme of validation and ‘being seen’, evidenced in stories of past invalidation that had been internalised into the self-structure and defended against by presenting a ‘defended’ self. Self-harm enabled this ‘unseen self’ to be expressed, validated and contained. Recovery was storied in terms of internalising experiences of validation, which enabled integration of the invalidated parts of the self. Many of the participants highlighted how their scars told a story of discovery; of becoming, coping and surviving. In the healing of scars this recovery is evident, but they may also continue to convey the unseen and unspoken experiences of pain, incoherence and invalidation. Self-harm and remaining scars may be understood as connecting, containing and re-embodying the internalised invalidation and ‘unseen’ aspects of the self. These findings are discussed with reference to the clinical implications, strengths and limitations of the methodology and directions for future research.
33

Kritické zhodnocení metody tapingu se zaměřením na jeho účinky / Critical evaluation of taping methods with focus on its effects

Šolcová, Veronika January 2011 (has links)
Title: Critical evaluation of taping methods with focus on its effects. Objectives: Purpose of this diploma thesis is critical evaluation of taping methods with concentration on its effects. Evaluation, comparison of contradictory statements and obtained information will be done based on a study and analysis of literature and scientific studies regarding taping methods and its efficiencies. On this base, final conclusions about real efficiency of taping will be made. Methods: In this diploma thesis, which is a critical review, document studies method will be used, along with analysis of professional scientific sources and their comparison. Results: The sport tapes (solid and elastic) and the kinesio tapes may participate on the possible mechanisms of the taping method effect. The various kinds of the tapes are different in the consequences of its effects. For lack of good scientific studies we can not clearly objectify the method of the taping. Keywords: taping, taping methods, taping efficiency, knesio taping, benefits of taping, prevention, critical review, proprioception, scars.
34

CICATRIZES ABERTAS PELOS RISCOS RODRIGUEANOS.

Aguiar, Daura Maria Guimarães 03 December 2013 (has links)
Made available in DSpace on 2016-08-10T11:07:13Z (GMT). No. of bitstreams: 1 DAURA MARIA GUIMARAES AGUIAR.pdf: 1153241 bytes, checksum: d9ba967a6b63ae403a7d9451aa7aba89 (MD5) Previous issue date: 2013-12-03 / This paper conducts a study of the work Cicatrizes do Risco ou Crepúsculo das Luzes, by Cida Rodrigues , published in 2001, dealing with themes that relate to the fragmentation of human being in time and space, his reminiscences of childhood and distressing obsession with writing. The act of writing is a kind of exorcism of what will be inside this moment that speaks for itself, through the first person of the verb and, sometimes, is shown by an omniscient narrator, capable of stripping the most covert thoughts of this character not shown in full and not allowed to touch. Other times, shown by the lyrical voice of the fragments that make up the "Moments " (chapters) that make up the work, the corpus of this work. This dissertation also is an attempt to reveal the estrangement caused at the outset, the "Moments" that open each part of the work under study, as well as a typical writing postmodernity, marked by the mixture of literary genres moving freely between prose and poetry, and these are presented in many different ways, making the result of the trial set of literary writing. / O presente trabalho realiza um estudo da obra Cicatrizes do Risco ou Crepúsculo das Luzes, de Cida Rodrigues, publicada em 2001, tratando de temas que se relacionam à fragmentação do ser no tempo e no espaço, suas reminiscências da infância e a angustiante obsessão pela escrita. O ato de escrever representa uma espécie de exorcismo do que vai por dentro deste ser que ora fala por si mesma, através da primeira pessoa do verbo e, ora, é mostrada por um narrador onisciente, capaz de desnudar os mais encobertos pensamentos desta personagem que não se mostra por inteiro e não se deixa tocar. Outras vezes, revela-se pela voz do eu lírico nos fragmentos que compõem os Instantes (capítulos) que constituem a obra, corpus deste trabalho. Esta dissertação é, ainda, uma tentativa de revelar o estranhamento provocado, logo de início, pelos Instantes que abrem cada parte da obra em estudo, bem como por uma escrita típica da pós-modernidade, marcada pela mistura de gêneros literários transitando livremente entre a prosa e a poesia, sendo que estas se apresentam das mais variadas formas, fazendo configurar o resultado da experimentação da escrita literária.
35

Contribution à l'analyse des facteurs déterminant les fibroses graves du foie (bilharziose) et de la peau (tissus chéloïdes) / Contribution to the analysis of genetics factors of liver (bilharziasis) and skin (keloids) severe fibrosis

Duflot, Nicolas 21 December 2018 (has links)
Les fibroses anormales sont responsables de plus de 40% des décès pour raison médicale ; elles se développent suite à une inflammation chronique. Les fibroses hépatiques causées par les schistosomes et par le virus HCV sont en grande partie déterminées par la génétique du malade. Notre thèse a consisté à poursuivre le travail de caractérisation du déterminisme génétique des fibroses hépatiques et cutanées.La première partie de notre thèse, est l’étude informatique et statistique des données de génotypage GWAS de Brésiliens qui présentent une fibrose hépatique bilharzienne grave sur plus de 2,5 millions de SNPs. 180 SNPs qui montraient une association suggestive avec les fibroses graves ont été sélectionnés, dont certains affectent les gènes des voies Wnt. Ces SNPs ont été testés sur une cohorte de 460 pêcheurs ougandais exposés à S.mansoni et nous avons confirmé l’association avec la fibrose de 4 SNPs.La deuxième partie de notre thèse est l’analyse transcriptômique (RNA-Seq) des mécanismes responsables des fibroses anormales de la peau de sujets affectés par des fibroses chéloïdes de 20 tissus chéloïdes, 7 tissus sains et 7 tissus affectés par des cicatrices hypertrophiques. Cette analyse montre que le développement des chéloïdes est la conséquence d’une stimulation anormale des voies de la cicatrisation en partie due à l’activation de la voie Wnt βcatenin et Wnt PCP. Pour conforter cette proposition, nous avons effectué une analyse génétique de la voie Wnt dans deux cohortes indépendantes. L’analyse statistique montre que des SNPs dans 6 gènes de la voie Wnt βcatenin contribuent au développement des fibroses chéloïdes. / Abnormal fibrosis is responsible for more than 40% of medical deaths. They develop as a result of chronicinflammation. Hepatic fibroses caused by schistosomes andHCV virus are largely determined by the genetic background of the patient. Our thesis consisted of continuing thework of characterizing the genetic determinism of liver and skin fibrosis.The first part of our thesis is the computer and statistical study of GWAS genotyping data of Brazilians whohave severe bilharzeal liver fibrosis on more than 2.5 million SNPs. 180 SNPs that showed suggestive associationwith severe fibrosis were selected, some of which affect the Wnt pathway. These SNPs were then tested on a cohortof 460 Ugandan fishers exposed to S.mansoni and the results confirmed the association of 4 SNPs with fibrosis.The second part of our thesis is the genomic analysis (transcriptome and genetics) of the mechanismsresponsible for the abnormal skin fibrosis with subjects affected by keloid scars. We performed an analysis of genes(RNASeq) expressed differently between 20 keloids, 7 healthy tissues and 7 tissues affected by hypertrophic scars.This analysis shows that the development of keloids is the consequence of an abnormal stimulation of cicatrizationpathways with strong activation of the Wnt βcatenin and Wnt PCP pathway. To support this proposal, we performeda genetic analysis of the Wnt pathway in two independant cohorts.The statistical analysis of the results shows that polymorphisms in 6 genes of the Wnt βcatenin pathway contributeto the development of keloid fibrosis.
36

Special states in quantum many-body spectra of low dimensional systems

Nagara Srinivasa Prasanna, Srivatsa 06 September 2021 (has links)
Strong quantum correlations between many particles in low dimensions lead to emergence of interesting phases of matter. These phases are often studied through the properties of the many-body eigenstates of an interacting quantum many-body system. The folklore example of topological order in the ground states is the fractional quantum Hall (FQH) effect. With the current developments in the field of ultracold atoms in optical lattices, realizing FQH physics on a lattice and being able to create and braid anyons is much awaited from the view point of fault tolerant quantum computing. This thesis contributes to the field of FQH effect and anyons in a lattice setting. Conformal field theory has been useful to build interesting lattice FQH models which are few-body and non-local. We provide a general scheme of truncation to arrive at tractable local models whose ground states have the desired topological properties. FQH models are known to host anyons, but, it is a hard task when it comes to braiding them on small sized lattices with edges. To get around this problem, we demonstrate that one can squeeze the anyons and braid them successfully within a smaller area by crawling them like snakes on modest sized open lattices. As a numerically cheap approach to detect topological quantum phase transitions, we again resort to anyons that are only well defined in a topological phase. We create defects and study a simple quantity such as the charge of the defect to test whether the phase supports anyons or not. On the other hand, with the advent of many-body localization (MBL) and quantum many-body scars, interesting eigenstate phases which were otherwise only known to occur in ground states have been identified even at finite energy densities in the many-body spectra of generic systems. This thesis also contributes to the field of non-equilibrium physics by portraying models that display interesting non-ergodic phases and also quantum many-body scars. For instance, we show that an emergent symmetry in a disordered model can be used as a tool to escape MBL in a single eigenstate while not preventing the rest of the states from localizing. This can lead to an interesting situation of weakly broken MBL phase where a non-MBL state lives in the spectrum of MBL like states. We also demonstrate the emergence of a non-ergodic, but also a non-mbl phase in a non-local model with SU(2) symmetry. We provide two constructions of rather different models with quantum many-body scars with chiral and non-chiral topological order.
37

Berechnung von STM-Profilkurven und von Quantenbillards endlicher Wandhoehe

Sbosny, Hartmut 20 October 1995 (has links)
Die Arbeit befasst sich mit zweierleiZum einen wird der STM-Abbildungsprozess simuliert, indem Probe und Spitze durch zweidimensionale Sommerfeld-Metalle frei waehlbarer Geometrie beschrieben werden und der Tunnelstrom im Transfer-Hamiltonian-Formalismus bestimmt wird. Die Berechnung der Eigenzustaende der Elektroden erfolgt numerisch durch Diskretisierung der Schroedingergleichung im Differenzenverfahren. Ueber die geometrische Entfaltung der erhaltenen Konstantstromprofile mit der Spitzengeometrie werden der Vergleich zum geometrischen (mechanischen) Abtasten gezogen und Moeglichkeiten einer Vermessung von Spitze und Probe diskutiert. Zum anderen wird durch Berechnung von Eigenzustaenden in grossen zweidimensionalen Potentialkaesten (Quantenbillards) endlicher Wandhoehe der Frage nachgegangen, welchen Einfluss klassisch verbotene Gebiete (Aussenraum, Tunnelbarriere) auf Eigenfunktionen in semiklassisch grossen Systemen haben. Betrachtet wird insbesondere ein Gesamtsystem bestehend aus zwei Potentialkaesten, die ueber eine Tunnelbarriere koppeln (¨Quantenbillards endlicher Wandhoehe im Tunnelkontakt¨). Bei einer Reihe von Zustaenden zeigen sich Scars, die aus der Barriere austreten und in diese zuruecklaufen. Das Gesamtsystem ist in hohem Masse nichtintegrabel, ¨sichtbar¨ wird dieses aber nur fuer Bahnen entweder des Kontinuums oder fuer komplexe Orbits. Eine semiklassische Beschreibung dieses Phaenomens mit der gegenwaertigen, auf klassischen Orbits fussenden Theorie periodischer Bahnen ist nicht mehr moeglich. Die Einbeziehung komplexer Orbits oder Bahnen des Kontinuums (¨ungebundener Orbits¨) wird durch diese Ergebnisse angemahnt.
38

Historic Fire Regimes on Eastern Great Basin (USA) Mountains Reconstructed from Tree Rings

Kitchen, Stanley G. 08 March 2010 (has links) (PDF)
Management of natural landscapes requires knowledge of key disturbance processes and their effects. Fire and forest histories provide valuable insight into how fire and vegetation varied and interacted in the past. I constructed multi-century fire chronologies for 10 sites on six mountain ranges representative of the eastern Great Basin (USA), a region in which historic fire information was lacking. I also constructed tree recruitment chronologies for two sites. I use these chronologies to address three research foci. First, using fire-scar data from four heterogeneous sites, I assert that mean fire interval (MFI) values calculated from composite chronologies provide suitable estimates of point MFI (PMFI) when sample area size is ≈&frac; ha. I also suggest that MFI values for single trees can be used to estimate PMFI after applying a correction factor. Next, I infer climate effects on regional fire patterns using 10 site chronologies and tree-ring-based indices of drought and of El Niño Southern Oscillation (ENSO) and Pacific Decadal Oscillation ([PDO), Pacific Ocean surface temperature variability known to affect North American climate. Regional fire years (≥33% of recording sites) were synchronized by wet-dry cycles where the probability of occurrence was highest in the first year of drought following a wet phase and lowest when climate conditions transitioned from dry to wet. Regional fire probability was highest when ENSO and PDO were negative (Southwest pattern). Local fire years occurred under a broad range of conditions. Fire seasonality was bimodal with early and late-season fires dominant. I imply that Native American burning practices were responsible for differences in historic and modern fire seasonality. Lastly, I assess fire regime and tree recruitment variability within two fire-sheds. PMFI varied more than 10-fold within each site. A mixed-severity regime was dominant. A majority (>60%) of fires were small (<10 ha) but together accounted for a minor proportion of area burned. Recruitment pulses varied spatially from stand to landscape-scales and were often synchronous with multi-decade, fire-quiescent periods. I recommend that management strategies employ fire and fire-surrogate treatments to restore disturbance processes to these and similar landscapes at spatial and temporal scales consistent with the historic record.
39

Body mapping as an exploratory tool to enhance dialogue of life experiences with adolescent boys in a special youth centre

Pienaar, Marinda 11 1900 (has links)
This qualitative study explored the use of Body Mapping as a tool to enhance dialogue with sentenced adolescent boys in a Special Youth Centre. Their scars and tattoos were regarded as the key to unlocking their life stories. Body maps and unstructured interviews formed the main body of data. The paradigms of both Gestalt- and occupational therapy formed the basis of the conceptual framework and a literature control was done as “theory after” as well as a method of data triangulation. Themes extracted pointed to broken bonds and familial trauma which lead the adolescents to search for belonging and mastery in deviant peer groups and street- and Numbergangs. The tattoos provide graphic affirmation of identification and belonging to these groups. The mapping of their lesions and scars provided the opportunity to relate traumatic experiences. Conclusions were drawn and recommendations could be made as a result of the study. / Social Work / M. Diac. (Play Therapy)
40

Une contribution au chaos ondulatoire expérimental

Mortessagne, Fabrice 11 December 2006 (has links) (PDF)
Au travers d'une sélection d'articles, ce document propose de suivre le parcours de l'auteur dans le vaste et riche domaine du chaos ondulatoire. L'accent est en particulier mis sur les activités expérimentales dont il a été l'initiateur, et qu'il anime actuellement. Le lecteur parcourra ainsi plusieurs ordres de grandeur de longueurs d'onde : de quelques centaines de nanomètres à la dizaine de centimètres, et croisera des objets aussi simple, en apparence, qu'une boîte en cuivre, ou de plus haute technologie, comme une fibre optique amplificatrice à double cœur ! Il verra des comportements universels à l'œuvre, mais aussi des attitudes violemment atypiques, comme font montre les \emph{scars} et les \emph{modes localisés}. Et, si l'objectif du document est atteint, il sortira de sa lecture convaincu que les travaux menés par l'auteur concourent efficacement à un seul et même objectif : comprendre les mécanismes de propagation des ondes dans les milieux complexes.

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