Dissertations / Theses on the topic 'Local disorder'

In recent years, doped ceria compounds have attracted increasing attention as electrolytes for application in Solid Oxide Fuel Cell devices, thanks to their high performance at intermediate temperature. In cerium oxide, ionic conductivity is driven by the presence of oxygen vacancies, introduced for charge balance after doping with a lower valent cation. With increasing doping concentration the oxygen diffusion is impeded, probably because of the formation of aggregates that trap oxygen vacancies. Their nature is though still under debate. Owing to the close interplay between transport properties and local structure, an accurate description of the defects on the atomic scale is of the utmost importance for understanding the mechanisms at work in doped ceria. In this study we propose to unveil the complex disorder in doped ceria with a combined powder diffraction study. On the one hand, X-ray and Neutron powder diffraction are joint to couple their potentialities; on the other hand, two different crystallographic approaches are exploited. The conventional crystallographic methods allow to study the long range structure modifications that occur with doping. The Pair Distribution Function is instead employed to study the local structure, in terms of deviations from the long range atomic ordering. The goal of the thesis is to provide a crystallographic description of the atomic rearrangements induced by doping, looking for a relationship between the local structure and the transport properties.

Background – Previous reports of abnormal auditory N2 and P3 event-related potentials (ERPs) suggest impaired discrimination, evaluation or context updating for infrequent target stimuli in post-traumatic stress disorder (PTSD). This study examines each of these processes by investigating high-resolution ERP topography during target detection for visual word stimuli. Method – ERPs were recorded at 124 electrodes from 10 PTSD patients and 10 matched controls. Target detection tasks comprised blocks of equally probable red and blue words, with low probability target events. Detection of fixed target words in one color provided the basis for measurement of selective attention for color, stimulus evaluation and target detection processing. Alternative task instructions, with the same stimuli, required detection of any consecutive word repeats in an attended color, which demands working memory updating for nontarget words. Comparison of attended non-target words from each task indicates the extra activity for updating working memory representations of target attributes. Thus, specific condition comparisons provide measures of stimulus discrimination and evaluation, working memory updating and target detection. Results – PTSD patients had slower and less accurate motor responses in both tasks, with greater inaccuracy during the variable target task. There was abnormal ERP activity in PTSD at 200-300 ms in the left posterior temporal region during stimulus discrimination and target recognition. During evaluation of attended non-target words, PTSD patients demonstrate deficits in frontal and parietal regions at 400-500 ms. During working memory updating, at 400-600 ms, there was a delay in frontal activation, followed by smaller activity in parietal areas in PTSD. During target word recognition, PTSD patients demonstrate deficits in frontal activity, with greater occipital and parietal activity. Conclusions – These findings indicate impaired evaluation and integration of new information in working memory. In particular, the results suggest failure in frontal executive systems, with greater dependence on visual processing for effective target detection. The current findings are consistent with neuropsychology studies that identify deficits of attention and memory for verbal information in PTSD. This study provides insight into the temporal components of attention and working memory in PTSD. It is proposed that working memory deficits arise from disruption to synchronized activity in distributed networks engaged in working memory processes.

We illustrate self-assembly with several systems which aim to harness the process of assembly to create new functional structures. The concept of kinetic trapping preventing assembly and the importance of reversibility, breaking as well as making bonds, for avoiding such traps are introduced. We aim to identify how reversible systems are, with the aim of aecting the prediction, control and design of new systems. In four systems a lattice gas model, and three models based upon patchy particle schemes, a yield is dened and used to identify optimal assembly at a given time. Three measurements relevant to reversibility are described, applied, and compared with the results of similar studies. The rst simply counts the bonding and un-bonding events, or kinks, over the whole assembly process and compares the total number of events with the net bonding events. We measure values of 100 􀀀 1000kinks per bond in crystal systems, and 60 􀀀 200 for closed structures. In analogy with a toy model the values can be related to a `forgivingness', a ratio of bad bonding sites, to good ones. We then turn to measurements at early times which allow for the prediction of when assembly will occur. These include rate measurements of kinks which provide an instant measure of reversibility and comparison of correlation and response functions with the equilibrium uctuation dissipation theory. These methods examine the dynamics of the assembly process while our third approach examines the structures during assembly. We examine how each of the measurements provide information about the assembly process and how it relates to the particles, their interactions and the nal structure. The possibility of using the methods in combination is shown to be relevant to the prediction of assembly and how they might be used to implement design and control schemes to improve assembly.

Visuospatial abilities are considered essential to our interaction with the environment and are involved in many every-day activities (Hegarty & Waller, 2005; Jansen, Wiedenbauer, & Hahn, 2010). A useful way to approach this neuropsychological domain is the global-local paradigm, according to which, people may attend an event using a global processing style, in which they consider the gestalt of a set of stimuli, or a local processing style, in which they focus on details (Förster & Dannenberg, 2010; Navon, 1977; Schooler, 2002). An abundance of research on global versus local processing has revealed preferential processing styles (with a global or local bias) in specific neurodevelopmental disorders, particularly as concerns Autism Spectrum Disorders (ASD) (Caron, Mottron, Dawson, Bertiaume, & Dawson, 2006; Kuschner, Bodner, & Minshew, 2009). Conflicting findings have often emerged in the literature (see for example Van der Hallen, Evers, Brewaeys, Van den Noortgate, & Wagemans, 2015), however, showing that participants with different developmental disorders can process both global and local information, depending on the task requirements and the cognitive domain involved, but in different and atypical ways (Dukette & Stiles, 2001). These results prevent possible generalizations and need to be further explored. Differently, global and local processing styles have never been studied in children with other neurodevelopmental disorders, such as Nonverbal Learning Disabilities (NLD), even though there is evidence to suggest that the issue could be relevant in individuals with NLD as well (Chow & Skuy, 1999). For this reason, cross-task and cross-syndrome comparisons are suggested as the best way to analyze these processing abilities and reveal similarities and differences in global and local processing styles in neurodevelopmental disorders (D’Souza, Booth, Connolly, Happé, & Karmiloff-Smith, 2016). The main aim of this PhD dissertation is to improve our understanding of the role of global and local visuospatial processing in the neuropsychological profile of specific neurodevelopmental disorders, using cross-task and cross-disorder comparisons. Children with ASD without intellectual disability (ID) or NLD were tested in terms of their performance in different domains of visuospatial skills, comparing them with each other and with children who had other neurodevelopmental disorders, such as dyslexia or Attention Deficit Hyperactivity Disorder (ADHD). The assessment focused on visuospatial processing speed, visuo-perceptual and visuo-constructive abilities, visuospatial working memory (VSWM), and their interplay with local and global processing. Based on the modified Block Design Task (BDT) paradigm (Caron et al., 2006), new tasks and stimuli have been devised in order to assess the previously mentioned visuospatial abilities, and four studies have been carried out. Study I aimed to make a cross-task comparison on global-local visuospatial processing in two groups of participants with ASD without ID – with and without a visuospatial peak (–P and –NP) – comparing them with matched typically developing (TD) individuals. The results helped us to clarify the visuospatial profile of the two groups of individuals with ASD, demonstrating the importance of taking specific factors into account (i.e. the visuospatial domains examined and the perceptual reasoning abilities). Participants with ASD-NP performed poorly in all domains, revealing weaker spatial integration abilities in the visuo-perceptual domain and a diminished sensitivity to perceptual coherence in the VSWM, while the ASD-P group used both global and local processing effectively according to the task, and a local bias only emerged in the visuo-constructive task. In agreement with D’Souza and coauthors (2016), our results support the conviction that labelling individuals with ASD as ‘local processors’ is restrictive. They may use both local and global processing styles depending on the demands of the task in hand, the visuospatial domain involved and their cognitive visuospatial functioning. Study II (Chapter 3) aimed to investigate global and local visuospatial processing in children with symptoms of NLD comparing them with children with symptoms of dyslexia and with TD controls. The results showed that children with symptoms of NLD were less accurate in visuo-constructive tasks, while children with symptoms of dyslexia were only slightly impaired in a visuo-constructive task, but clearly slower in the perceptual task. Children with symptoms of NLD were less able to benefit from different levels of coherence of the stimuli, probably as a consequence of their less flexible and efficient visuospatial processes (Mammarella, & Cornoldi, 2005). In particular, the global dominance mechanism (Navon, 1977) made it more complicated for the group with symptoms of NLD to switch from a global to a local processing, which was needed to complete the visuo-constructive task correctly. After investigating the issue of global and local visuospatial processing separately for ASD without ID and NLD, the aim of Study III (Chapter 4) was to draw a cross-disorders comparison, highlighting similarities and differences across three clinical profiles - ASD without ID, NLD and ADHD - as compared with TD controls. Our results revealed different visuospatial profiles for the groups considered, and suggested the utility of manipulating the coherence of stimuli to investigate visuospatial skills. Marked deficit in all the visuospatial domains emerged for the group with NLD, confirming that impairments in the visuospatial domain are core and distinctive symptoms of this disorder (Cornoldi, Mammarella, & Fine, 2016; Semrud-Clikeman, Walkowiak, Wilkinson, & Christopher, 2010). In addition, difficulty in integrating local configurations in a coherent whole emerged for the visuo-perceptual domain. A heterogeneous profile emerged for children with ADHD, which showed, consistently with previous studies, impairment in the visuospatial processing speed domain and in VSWM (Martinussen, Hayden, Hogg-Johnson, & Tannock, 2005; Weigard & Huang-Pollock, 2017). Moreover, these participants presented some difficulties in visuo-constructive abilities when they had to deal with global configurations, while they performed normally in visuo-perceptual task. Differently, participants with ASD performed normally in all the examined domains, using effectively both global and local visuospatial processes, with the sole exception of the visuo-constructive task in which this group showed slower response times and a diminished sensitivity to perceptual coherence (Caron et al., 2006; Shah & Frith, 1993). Finally, since individuals with NLD and those with High Functioning Autism or Asperger Syndrome (DSM-IV TR, American Psychiatric Association [APA], 2000) are often confused, Study IV (Chapter 5) included a further comparison between ASD and NLD. Visuo-constructive abilities and VSWM were investigated in a subgroup of participants with ASD without ID and without a visuospatial peak (ASD-NP) and in a group with NLD. Thus, Study IV aimed to analyze whether ASD-NP – though not representative of the ASD without ID population as a whole– shared any characteristics with the NLD group. Once again, our results differentiate the visuospatial profile of children with NLD from that of children with ASD. The former group showed an impaired performance in all the domains examined affecting both global and local levels of processing. The ASD group had a more heterogeneous profile, with normal performance in VSWM and in the drawing of a complex figure, slower response times in the segmented condition of visuoconstructive BDT and a more local and fragmented drawing style in the recall of a complex figure. Here again, local bias affected the performance of participants with ASD in tasks demanding visuoconstructive skills that specifically involved combining parts to form a single whole (Simic, Khan, & Rovet, 2013). General conclusions derived from the main findings of the four studies, and both clinical and educational implications will be thus highlighted in the final chapter of this dissertation. To conclude, investigating visuospatial abilities and global-local processing in individuals with neurodevelopmental disorders offer crucial insight for the analysis of the strengths and weaknesses of the clinical profiles examined and for their differential diagnosis. There is still space for further research on the domains of visuospatial abilities, and on the general neuropsychological functioning of children with different neurodevelopmental disorders. This dissertation was an effort to raise and clarify some points, however other questions remain open and will require further studies.
Le abilità visuospaziali sono un insieme di abilità considerate essenziali nell’interazione con l’ambiente e sono coinvolte in numerose attività quotidiane (Hegarty & Waller, 2005; Jansen, Wiedenbauer, & Hahn, 2010). Il paradigma di elaborazione globale-locale (Navon, 1977) costituisce un utile approccio per studiare questo dominio neuropsicologico. Secondo tale paradigma le persone possono percepire un evento usando uno stile di elaborazione globale, per cui considerano la gestalt di un insieme di stimoli, o uno stile di elaborazione locale, per cui si focalizzano sui dettagli (Förster & Dannenberg, 2010; Navon, 1977; Schooler, 2002). Numerose ricerche sull’elaborazione globale-locale hanno rivelato l’uso preferenziale di uno stile di elaborazione (con un bias globale o locale) in specifici disturbi del neurosviluppo, in particolare riguardo al disturbo dello spettro dell’autismo (ASD) (Caron, Mottron, Dawson, Bertiaume, & Dawson, 2006; Kuschner, Bodner, & Minshew, 2009). Tuttavia, risultati conflittuali sono spesso emersi in letteratura (vedi Van der Hallen, Evers, Brewaeys, Van den Noortgate, & Wagemans, 2015) e mostrano come i partecipanti con differenti disturbi dello sviluppo possono elaborare sia informazioni locali che globali, a seconda delle richieste del compito e del dominio cognitivo coinvolto, ma in modi differenti e atipici (Dukette & Stiles, 2001). Questi risultati prevengono possibili generalizzazioni e necessitano di essere ulteriormente esplorati. Al contrario, gli stili di elaborazione globale-locale non sono mai stati studiati in bambini con altri disturbi del neurosviluppo, come il disturbo dell’apprendimento nonverbale (NLD), nonostante evidenze abbiano suggerito che questi aspetti possano essere rilevanti anche nell’NLD (Chow & Skuy, 1999). Per tale ragione, confronti tra differenti disturbi del neurosviluppo e attraverso l’uso di diversi compiti vengono suggeriti come il metodo migliore per analizzare queste abilità ed evidenziare similitudini o differenze nell’uso degli stili di elaborazione (D’Souza, Booth, Connolly, Happé, & Karmiloff-Smith, 2016). L'obiettivo principale della presente tesi di Dottorato è quello di migliorare la nostra comprensione del ruolo dell’elaborazione visuospaziale globale-locale nel profilo neuropsicologico di specifici disturbi del neurosviluppo, attraverso la comparazione di diversi disturbi e l’uso di prove differenti. Sono state indagate le prestazioni di partecipanti con ASD senza disabilità intellettiva (ID) o NLD in diversi domini di abilità visuospaziali, confrontandoli tra loro e con bambini aventi altri disturbi del neurosviluppo, come la dislessia o il deficit di attenzione/iperattività (ADHD). L’assessment si è concentrato sull’indagine della velocità di elaborazione visuospaziale, delle abilità visuo-percettive, visuo-costruttive e di memoria di lavoro visuospaziale (VSWM). È stata inoltre indagata l’interazione tra le performance in questi domini e l'elaborazione globale-locale. Sulla base del paradigma modificato di disegno con cubi (BDT) (Caron et al., 2006), sono stati elaborati nuovi compiti e stimoli per valutare le abilità visuospaziali menzionate. In particolare, sono stati condotti quattro studi. Lo Studio I ha indagato gli stili di elaborazione visuospaziale globale-locale in due gruppi di partecipanti con ASD senza ID - con e senza un picco visuospaziale (-P e -NP) - confrontandoli con individui a sviluppo tipico (TD). I risultati hanno permesso di chiarire il profilo visuospaziale dei due gruppi di partecipanti con ASD, dimostrando l’importanza di tenere in considerazione fattori specifici (come i domini di abilità visuospaziali esaminati e le abilità di ragionamento percettivo dei partecipanti). I partecipanti con ASD-NP hanno ottenuto scarsi risultati in tutti i domini, mostrando inferiori capacità di integrazione spaziale nel dominio visuo-percettivo e una ridotta sensibilità alla coerenza percettiva nella VSWM, mentre il gruppo ASD-P ha utilizzato entrambe le strategie di elaborazione globale e locale in modo efficace in base al compito e un bias locale è emerso solo nel compito visuo-costruttivo. In accordo con D'Souza et al. (2016), i nostri risultati sostengono la convinzione che etichettare gli individui con ASD come "local processors" sia restrittivo. Infatti, essi possono utilizzare entrambi gli stili di elaborazione locale e globale a seconda delle richieste del compito, del dominio visuospaziale coinvolto e del loro funzionamento cognitivo di tipo visuospaziale. Lo studio II (Capitolo 3) ha indagato l'elaborazione visuospaziale globale-locale nei bambini con sintomi di NLD confrontandoli con bambini con sintomi di dislessia e con TD. I risultati hanno mostrato un’accuratezza inferiore per i bambini con sintomi di NLD nel compito visuo-costruttivo, mentre i bambini con sintomi di dislessia hanno mostrato lievi difficoltà nel compito visuo-costruttivo e una chiara lentezza in quello viuso-percettivo. Inoltre, i bambini con sintomi di NLD si sono mostrati meno in grado di beneficiare dei diversi livelli di coerenza degli stimoli, probabilmente come conseguenza dei loro processi visuospaziali meno flessibili ed efficienti (Mammarella & Cornoldi, 2005). In particolare, il meccanismo di dominanza globale (Navon, 1977) ha reso più complicato per il gruppo con sintomi di NLD il passaggio dall’elaborazione globale a quella locale, necessario per completare correttamente il compito visuo-costruttivo. Dopo aver esaminato l’elaborazione visuospaziale globale-locale separatamente per ASD senza ID e NLD, lo scopo dello Studio III (Capitolo 4) era quello di effettuare un confronto tra disturbi, evidenziando somiglianze e differenze tra tre profili clinici - ASD senza ID, NLD e ADHD - rispetto ai TD. I nostri risultati hanno rivelato diversi profili visuospaziali per i gruppi considerati e suggerito l'utilità di manipolare la coerenza degli stimoli per l’indagine di tali abilità. Per il gruppo con NLD è emerso un deficit marcato in tutti i domini visuospaziali, a conferma che le difficoltà in tale dominio costituiscono sintomi fondamentali e distintivi di questo disturbo (Cornoldi, Mammarella & Fine, 2016, Semrud-Clikeman, Walkowiak, Wilkinson e Christopher, 2010). Inoltre, per il dominio visuo-percettivo è emersa la difficoltà di integrare le configurazioni locali in un insieme coerente. Per il gruppo con ADHD si è evidenziato un profilo eterogeneo, i partecipanti con tale diagnosi hanno mostrato, in linea con gli studi precedenti, un deficit nel dominio di velocità di elaborazione visuospaziale e nella VSWM (Martinussen, Hayden, Hogg-Johnson & Tannock, 2005, Weigard & Huang-Pollock, 2017). Inoltre, questi partecipanti hanno presentato alcune difficoltà nelle abilità viso-costruttive quando dovevano ricostruire configurazioni globali, mentre sono emerse abilità visuo-percettive in norma. Diversamente, i partecipanti con ASD hanno mostrato prestazioni in norma in tutti i domini esaminati, utilizzando efficacemente processi visuospaziali globali e locali, con l'unica eccezione del compito visuo-costruttivo in cui questo gruppo ha mostrato tempi di risposta più lenti e una sensibilità ridotta alla coerenza percettiva (Caron et al., 2006; Shah & Frith, 1993). Infine, considerato che i profili di individui con NLD e con autismo ad alto funzionamento o sindrome di Asperger (DSM-IV TR, American Psychiatric Association [APA], 2000) sono spesso confusi, nello Studio IV (Capitolo 5) è stato proposto un ulteriore confronto tra ASD e NLD. Le abilità visuo-costruttive e la VSWM sono state studiate in un sottogruppo di partecipanti con ASD senza ID e senza picco visuospaziale (ASD-NP) e in partecipanti con NLD. Lo scopo era quello di analizzare se il gruppo con ASD-NP - sebbene non rappresentativo dell'intera popolazione con ASD senza ID – condividesse o meno caratteristiche con il gruppo NLD. Ancora una volta, i nostri risultati hanno permesso di differenziare il profilo visuospaziale dei bambini con NLD da quello dei bambini con ASD. Il primo gruppo ha mostrato prestazioni deficitarie in tutti i domini esaminati sia per il livello di elaborazione locale sia per quello globale. Il gruppo con ASD ha mostrato invece un profilo più eterogeneo, con prestazioni in norma nella VSWM e nel disegno di una figura complessa, tempi di risposta più lenti nella condizione segmentata della prova visuo-costruttiva e uno stile di disegno locale e frammentato nel disegno a memoria di una figura complessa. Anche qui, il bias locale ha influenzato le prestazioni dei partecipanti con ASD in compiti che richiedevano competenze visuo-costruttive e nello specifico di combinare le parti per formare un unico insieme (Simic, Khan, & Rovet, 2013). Infine, le conclusioni generali derivate dai principali risultati dei quattro studi e le loro implicazioni cliniche ed educative sono state evidenziate nel capitolo conclusivo della presente tesi. Per concludere, l'analisi delle capacità visuospaziali e l'elaborazione globale-locale in individui con disturbi del neurosviluppo offrono una visione cruciale per l'analisi dei punti di forza e di debolezza dei profili clinici esaminati e per la loro diagnosi differenziale. C'è ancora molto spazio per ulteriori ricerche sulle capacità visuospaziali e sul funzionamento neuropsicologico generale dei bambini con diversi disturbi del neurosviluppo. La presente tesi ha avuto l’obiettivo di sollevare e chiarire alcuni punti, ma altre domande restano aperte e richiederanno ulteriori studi.

In this paper we have obtained expression for the contribution to DOS with the help of the method of the temperature Green functions. Multiple elastic electron scattering by impurities and structural inhomogeneities in graphene on a substrate, has been taken into account. The resulting expression for the contribution to DOS depends on temperature, concentration of impurities and the type of short-range order (structural heterogeneity). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35212

Concomitantly with lattice disorder, there is a discrepancy between local and global scales in relaxor ferroelectrics, in that structural distortions occurring at the local scale are not reflected in the average global structure which remains cubic. There is an absence of direct implementation of the local symmetry in the modeling of relaxors, despite its considerable, but often unacknowledged, ability to encode local features. Central to the thesis is an explicit account for local gauge symmetry within the first-principles-derived effective Hamiltonian approach. The thesis thus aims to consider how an extended symmetry allowing independent transformations at different points in space can effectively bridge local features and macroscopical properties. An underlying question the thesis also seeks to answer is whether the disorder-induced non-trivial interplay between local and global scales can be described from a topological point of view

Multiferroics are currently intensely investigated because the coexistence and coupling of ferroic arrangements brings about new physical effects and, for the few room-temperature examples, interesting prospects for applications in various fields. This interest is illustrated by the recent publication of several articles on multiferroics in high impact reviews over the last five years. The main goal of the thesis was to look for new multiferroics by exploiting overlooked and original polar and magnetic arrangements. We more precisely investigated compounds based on lead iron tungsten PbFe2/3W1/3O3 (PFW) and lead zirconate PbZrO3 (PZO) oxides. PFW displays long- and short-range both polar and magnetic orders (ferroelectric-relaxor and antiferromagnetic-spin-glass) while PZO is antiferroelectric with antiferrodistorsivity (oxygen tilts) and existence of ferroelectric instabilities. Combining various techniques from synthesis to electric, magnetic and structural characterizations, we demonstrated that it is possible to get a multiferroic compound (50%PFW-50%PZO) with coexistence of multiple ferroic and structural arrangements with room temperature properties of practical interest. This work opens new prospects in this rich field of multiferroics in peculiar by using antiferroelectrics.

Signaling mediated by Notch receptors and their ligands is essential in cell differentiation and morphogenesis in metazoans. As both receptors and ligands are cell-surface expressed proteins, Notch signaling is restricted to nearby interacting cells. The five human ligands of Notch receptors are all single-pass, type I transmembrane proteins consisting of an extracellular region involved in receptor binding and of a 100-150 residue intracellular tail. One of these ligands, Delta-like 4 (DLL4) is a human homologue of Drosophila Delta protein, and plays an important role in the development of blood vessels. The intracellular region of DLL4 (DLL4_IC) is required for receptor/ligand endocytosis, undergoes regulated intra-membrane proteolysis and, through its C-terminal PDZ binding motif, mediates the interaction of DLL4 with Dlg-1, a protein involved in the organization of cell-cell junctions. The sequence of DLL4_IC is very well conserved through evolution but does not encode any domain of known structure. Using a recombinant purified protein expressed from a codon-optimized synthetic gene, we demonstrate through various biophysical methods such as circular dichroism, size-exclusion chromatography, and NMR that DLL4_IC is globally disordered in solution, but can form inter-convertible local secondary structures in response to specific variations in the physico-chemical milieu, as well as in the presence of its target PDZ domain. Most of these conformational changes occur in the functionally relevant C-terminal segment. A computational study on the incidence and location of protein intrinsic disorder in 369 human receptors of the same transmembrane class of DLL4 provides evidence that disorder concentrates in the cytoplasmic tail of these proteins and represents a general phenomenon. In light of these findings, we propose that global disorder in the cytoplasmic tail, in concert with local pre-organization, may play a role in the function of DLL4 as well as in that of other single-pass transmembrane proteins.

Two prominent theories of perceptual functioning in autism were tested. WCC theory maintains that individuals with autism spectrum disorder (ASD) preferentially attend to local elements. EPF model, on the other hand, maintains that persons with ASD can attend to either the local or the global elements and that they are sensitive to small changes in environmental contingencies. Individuals with ASD and typically developing individuals (TD) performed both the selective attention task, which employed instructions about which level of the hierarchical figure to attend, and the divided attention task, which employed implicit contingencies to bias to which level of the stimulus to attend. A global advantage and global interference were found for both groups. Furthermore, ASD persons demonstrated sensitivity to the contingencies relative to TD persons. This supports the EPF model indicating that individuals with ASD perform as TD individuals for global forms but can more flexibly modify their default level of selection according to changes in environmental contingencies.
Deux théories perceptuels ont été testé. WCC clâme que les personnes qui présentent un trouble envahissant du développement (TED) montrent une inclination aux traitement locaux. EPF dit que les personnes avec TED peuvent traiter les niveau global ou local, et qu'ils sont sensibles aux petites différences dans les éventualités de l'environnement. Les personnes avec TED et le groupe de développement typique (DT) ont exécuté la tâche d'attention sélective, qui a employé des instructions duquel le niveau être présent, et la tâche d'attention divisée, qui a employé des éventualités implicites. Un avantage global et une interférence globale ont été trouvés pour les deux groupes. De plus, seulement les personnes avec TED ont démontré la sensibilité aux éventualités. Ces résultats soutiennent le compte d'EPF, et indiquent que les individus avec TED peuvent performer d'une manière caractéristique la tâche des formes globales, et peuvent modifier leur niveau implicite selon les changements subtils dans l'environnement.

Ab-initio results of the core-level shift and the distribution about the average for the 3d_5/2 electrons of Ag, Pd and 2p_3/2 of Cu are presented for the face-centered-cubic AgPd and CuPd random alloys. The complete screening model, which includes both initial and final states effects in the same scheme, has been used in the investigations.

The alloys have been modeled with a supercell containing 256 atoms. Density-functional theory calculations are carried out using the locally self consistent Green's function approach.

Results from the calculations clearly shows that the core-level shift distributions characteristic is Gaussian, but the components reveals a substantial difference in the FWHM (Full-Width at Half-Maximum). Comparison between the experimental and the calculated broadening shows a remarkable agreement.

Many children can find it difficult to adjust to the social and curriculum differences they encounter when they begin secondary school. For some children — particularly children with a special educational need (SEN) — a difficult transition from primary to secondary school undermines educational, social and emotional outcomes. Children diagnosed with an autism spectrum disorder (ASD) are known to be especially vulnerable at the time of secondary transition. It is well recognised amongst practitioners that these children have a profile of needs, including difficulties in social communication, problems coping with the sensory environment, and anxiety difficulties, which can potentially make changing schools particularly difficult. Despite this knowledge, there is a paucity of academic research that has focused specifically on this group of children at the time of secondary transition. This study aimed, for the first time, to examine the factors that both support and hinder a successful transition from primary to secondary school for children with an ASD in one local authority. Adopting an eco-systemic perspective and utilising a mixed methodology, this study investigated which potential intrinsic characteristics of the child and wider systemic factors influenced the secondary transition process for 15 children with an ASD. Children were seen twice in the space of 3 months — once before the process of changing school and once the move to secondary school was made. This longitudinal design enabled the examination of any possible changes in the views and perspectives of children, parents, and teachers during the transition process, in addition to the impact of systemic factors on the process. It also allowed for investigation of the possible pre-transition predictors — the intrinsic needs of the child with ASD — of a successful transition. Specifically, it was expected that children with better verbal ability, fewer autistic symptoms, fewer sensory issues, and reduced anxiety levels would experience a smoother transition. Unexpectedly, this study found no significant associations between pre-transition intrinsic ASD child characteristics and overall transition success. Nevertheless, it identified several systemic factors, including the child's identity, tensions over school choice, delay in placement decisions, lack of primary preparation and in-reach, which were found to have a strong influence on the process of secondary transition for the children and their families. Intriguingly, the children who transitioned from mainstream to specialist provisions were identified as experiencing particular difficulties coping with their new secondary school. These findings have important implications for the role of educational psychologists in the transition process.

Nowadays BaTiO3 is considered as one of the most relevant environmental-friend ferroelectric and, thank to the chemical substitutions at the Ba2+ and/or Ti4+ sites, its properties are usually tailor to meet a big variety of devices and performance requirements. A classical example is the solid solution BaTi1-xMIVxO3, where M could be Sn, Zr, Hf, Ce etc., whose ferroelectric behavior shows an almost continuous variation with composition. The study of these compounds is then essential to improve their characteristics and make their suitable in more applications. Considering that their properties are deeply linked to the structure and especially to structural defects, average and local structural analyses are essential to better understand the origins of different polar behaviours and to have a real control on these materials. Despite this need, only BaTi1-xZrxO3 (BTZ) system, which is one of the most popular dielectrics used in multilayer ceramic capacitors, has been investigated in some detail. Although the similarity to BTZ suggests that BaTi1-xCexO3 (BTC) may be promising as lead free actuator materials, studies on this solid solution are almost limited. Thus in this research the BTC solid solution has been structurally investigated in order to provide knowledge lacks. Different ceramic samples with different doping amounts and different polar behaviours (from normal ferroelecric to relaxor via diffuse phase transition) have been investigated at different temperatures. In addition, taking into account the current tendency in miniaturized devices required in microelectronics, also chemical equivalent nano powders have been considered to explore not only doping effects, but also that of size. Pair Distribution Function (PDF) with different type of approaches (as carbox, biphasic and so on) has been employed coupled with TEM analysis and Raman spectroscopy. A complete description of that BaTi1-xCexO3 materials is given underlining links between polar behaviours, temperature, doping and size effects.

Mestrado em Engenharia Alimentar - Processamento de Alimentos - Instituto Superior de Agronomia
In this study correlations between Rocha pear quality attributes and the incidence of internal browning (IB) were performed in order to know the major factors which determine different susceptibility of the fruit. Fruits under study were previously stored in dynamic controlled atmosphere (four months) and from three geographical origins (west region). The fruit incidence of IB showed to be dependent on geographical production localization. Fruits from Mafra and Lourinhã with 28 and 43% of IB, respectively, versus Alcobaça, where no symptoms were detected (0% IB). Fruits from Alcobaça showed the highest contents of ascorbic acid (AA) (4,8 mg/100 g) and of total phenolic compounds (CFT) (111,0 mg CAE/100 g), with increases of 20% and 40%, respectively, in comparison to the others, representing these the most distinctive quality factors. It was found that fruits with more calcium content, lesser potassium content and higher antioxidant capacity are more resistant to IB. By other side, the symptoms incidence is bigger in advanced post-harvest ripeness stages and minor AA content. The effects of AA content of the fruit on IB incidence were inconclusive. However, in the fruit core tissues the presence of similar AA contents between fruits, with and without IB, along with significant differences in CFT, could suggest that phenolic compounds are involved as a stress response to internal browning disorders mechanisms. Full ripening capacity was achieved in 4 days (room temperature) regardless fruits origin. However, fruits with higher internal browning incidence showed lesser storage ability (5 C), as a fresh-cut product

Thesis (Ph.D.)--Kent State University, 2008.
Title from PDF t.p. (viewed Sept. 28, 2009). Advisor: Stan Wearden. Keywords: journalism; trauma; broadcasting; reporting; television; posttraumatic stress; compassion fatigue. Includes bibliographical references (p. 164-184).

Theoretical investigations of spectroscopic and magnetic properties of metallic systems in the bulk, as well as in nanostructured materials, have been performed within the density functional theory. The major part of the present work studies the differences between binding energies of electrons tightly bound to the atoms, the so-called core electrons (in contrast with the valence electrons), that is, core-level binding energy shift (CLS).

By comparison between corresponding elemental core-levels for atoms situated in different chemical environments we obtain fundamental understanding of bonding properties of materials. The method of choice was the complete screening picture, which includes initial and final state effects on the same footing. The usefulness of CLS stems from that it is sensitive to differences in the chemical environment of an atom, which can be affected on one hand by the global composition of e.g. disordered materials, surfaces and interfaces, and on the other hand by the very local environment around an atom. Here CLSs have been obtained for both components in the fcc random alloys AgPd, CuPd, CuNi, CuPt, CuAu, PdAu, NiPd and NiPt. Moreover the model was extended to the Auger kinetic energy shift for the LMM Auger transition in AgPd alloys. Studies were also applied to the near surface and interface regions of PdMn nano structures on Pd(100), thin CuPd and AgPd films on inert Ru(0001), and at interfaces. The disorder broadening on CLS due to local environment effects was calculated in selected alloys.

A part of the thesis concern investigations related to the magnetic ordering in Invar alloys, including the influence of local environment effects. A study was made for the dependence of effective exchange parameter on the electron concentration, volume and local chemical composition.

The aim of this research is to gain the perspectives of key stakeholders involved in the process of identification, assessment, diagnosis and accessing of support for children with Autism Spectrum Disorder (ASD) in one Local Authority where concerns have arisen about increased prevalence rates. The present study is particularly concerned about the experiences of low socioeconomic status families that have children with ASD, at a time when inequalities across the Borough appear to be widening. The views of key stakeholders; parents, Educational Psychologists, Clinical Psychologists, Paediatrician, Psychiatrist, Speech and Language Therapists and Special Educational Needs Co-ordinators were sought in order to provide an insight into parental support needs and to inform thinking about how future service provision could be improved for low SES parents. The present study incorporates semi-structured interviews which were transcribed and analysed using thematic analysis. In total there were twenty one participants, comprising ten parents and ten professionals. The thematic analysis of the interviews identified a number of factors that impact on the identification, assessment, diagnosis and accessing of support for ASD. These are discussed under three main headings; parental support needs, perceptions of ASD within families and local communities and improving ASD service and provision. For parental support needs the key issues identified include; entitlement to support, support for families at home, financial implications, working in partnership, school provision, support groups and language barriers English as an additional language (EAL). With regard to perceptions of ASD within families and local communities, the key issues identified were family stress and perception of ASD within local communities. Finally, as part of improving ASD service and provision, key issues identified were the need for centralised information, the need for a multi-disciplinary team which make diagnoses, communicating diagnosis to family and the review process as part of an improved parent-professional partnership. The findings of the present study highlight the acute challenges that many low SES families may experience and further raise practical implications about improving ASD service provision and practice for this LA in the future.

Rappel de généralités sur l'analyse de la diffusion diffuse dans le cas d'un alliage binaire. Description détaillée de l'appareillage. Présentation des résultats des mesures de diffusion diffuse sur l'échantillon Au(70)Cu(30) recuit près de la température de transition ordre-désordre. Mesures de la résistivité et de l'allongement sous contrainte axiale, par diffusion diffuse. Etudes à partir de ces mesures, des cinétiques de mise en ordre local dans les alliages Au(75)Cu(25), Au(70)Cu(30) et Au(65)Cu(35). Analyse du rôle des lacunes.

L’incertitude est un processus cognitif communément expérimenté lors d’une prise de décision. Dansle trouble obsessionnel-compulsif (TOC), il est excessif et compromet les capacités décisionnelles del'individu.Ce travail avait comme objectif une meilleure compréhension des aspects physiologiques etphysiopathologiques de l’incertitude, au travers d'une double approche, comportementale etélectrophysiologique. Dans un premier temps, nous avons construit une tâche originale qui permetd'exprimer son incertitude au cours d'une prise de décision. Avec cette "tâche d’incertitude", nousavons exploré les relations entre mémoire de travail et incertitude. Nous avons montré que lescapacités de mémoire de travail prédisaient la propension à l'incertitude chez les volontaires sains alorsque l'incertitude était suivie d'une dégradation des performances mnésiques chez les patients TOC.Puis, nous avons trouvé une relation entre capacités mnésiques et incertitude dans une population depatients épileptiques caractérisée par des déficits mnésiques, confirmant ainsi le rôle des capacitésmnésiques dans la survenue de l'incertitude physiologique.Pour l'étude des corrélats neuronaux, nous avons mesuré l'activité électrophysiologique intracérébraledes régions impliquées dans la prise de décision au cours de la tâche d'incertitude, chez des patientsépileptiques pour les structures corticales et chez des patients TOC pour les structures sous-corticales.Nous avons montré que l'incertitude était associée à : 1/ une diminution d’amplitude des potentielsévoqués des régions préfrontales et prémotrices ; 2/ une moindre synchronisation des bandes defréquence alpha et bêta en temps-fréquence ; 3/ une augmentation de l'amplitude des potentielsévoqués dans le noyau sous-thalamique. Nos résultats suggèrent un défaut d'engagement des structurescorticales impliquées dans la prise de décision au cours de l'incertitude. Enfin, notre travail tend àconfirmer le rôle du noyau sous-thalamique dans la physiopathologie du TOC et dans les mécanismessous-tendant l’incertitude pathologique
Uncertainty is a cognitive process that frequently influences our decisions in everyday life. Inobsessive-compulsive disorder (OCD), the high level of uncertainty usually alters the decision-makingprocess.This work aimed to a better understanding of physiological and pathophysiological aspects ofuncertainty, by exploring its relationships with working memory abilities and its neural correlates. Anoriginal task derived from a delayed matching-to-sample task was created with the possibility toexpress felt uncertainty during decision-making. With this "uncertainty task", we demonstrated thatbaseline working memory abilities predicted the occurrence of uncertainty in healthy individualswhereas uncertainty was followed by a decrease in working memory abilities in OCD patients. Therole of working memory abilities in the occurrence of uncertainty was further confirmed in a clinicalpopulation of epileptic patients suffering from baseline working memory impairments.For the study of the neural correlates of uncertainty, we measured intracerebral local field potentials(LFPs) in regions involved in decision-making during the uncertainty task. Cortical and subcorticalLFPs were obtained in epileptic and OCD patients, respectively. We showed that uncertainty wasassociated with: 1/ a decreased amplitude of evoked responses in cortical prefrontal and premotorregions, 2/ a reduced synchronization of alpha-beta frequency bands in time-frequency analyses, 3/ anincreased amplitude of evoked responses in the subthalamic nucleus. Our findings suggested adiminished cortical activation in uncertain decision-making and confirmed the role of the subthalamicnucleus in OCD pathophysiology and in the mechanisms underlying the occurrence of pathologicaluncertainty

Dans une première partie nous explorerons les effets d'impuretés désordonnées et paramagnétiques sur l'effet spin-Hall intrinsèque dans un gaz d'électrons bi-dimensionnel avec un couplage spin-orbite de Rashba. A faible désordre, la conductivité de spin-Hall reste proche de sa valeur d'échantillon pur, comme le montrent un calcul analytique de réponse linéaire et une étude numérique. De fortes fluctuations sont toutefois observées, elles augmentent avec l'importance du désordre. Pour caractériser la dynamique d'un paquet d'onde sur un réseau, nous mesurons sa taille, le taux de participation inverse, et sa dimension de corrélation. Le système subit une transition de localisation à une valeur critique du désordre. Dans le régime localisé, la densité locale d'états n'est plus uniforme et ne coïncide plus avec la densité totale d'états. Une corrélation antiferromagnétique entre les impuretés et les électrons de conduction est observée. Après la transition de localisation, la conductivité de spin augmente significativement. La première correction quantique dans le formalisme de réponse linéaire, contribue positivement à la conductivité de spin-Hall. Dans une seconde partie, le modèle de Hubbard avec double échange avec corrélations électroniques est étudié par la méthode du champ moyen dynamique (DMFT) dans l'approximation de non-croisement pour la résolution du problème d'impureté (NCA). Autour du quart remplissage, un polaron orbital est observé et décrit à l'aide d'un Hamiltonien effectif. Le double échange dans les semi-conducteurs magnétiques dilués est étudié dans l'approximation du potentiel cohérent (CPA)
Spintronics is a research area that is concerned with the storage and transfer of information by means of electron spins. In the first part we investigated the intrinsic spin Hall effect in the presence of disordered magnetic impurities in a paramagnetic state in a two dimensional electron gas with Rashba spin-orbit coupling. In the presence of weak magnetic disorder the spin Hall conductivity stays close to its universal (clean system) value, as shown by analytical linear response calculations and numerical simulations. Heavy spin conductivity fluctuations are observed, that increase with disorder strength. To investigate the spreading of a wavepacket on a lattice we measure the wavepacket width, the inverse participation ratio and the (2)-fractal dimension. It is shown the system undergoes a localization transition at a critical disorder strength. In the localized regime the local density of states is not uniform anymore. An anti-ferromagnetic correlation between electron spins and impurity magnetic moments is observed. Beyond the localization transition the spin conductivity increases significantly. The first quantum (Cooperon) corrections in the linear response formalism are shown to contribute positively to the spin Hall conductivity. In the second part the double exchange Hubbard model for correlated electron systems is studied using dynamical mean field theory (DMFT) with the non-crossing approximation (NCA). Around quarter filling an orbital polaron is observed, numerically and in an effective Hamiltonian. Double exchange in dilute magnetic semiconductors is studied using the coherent potential approximation (CPA)

This thesis was motivated by the hypothesis that a continuum of cognitive style may exist in the general population, from strong to weak coherence. On this conceptualisation, individuals with autism spectrum disorder (ASD) are proposed to lie at the extreme weak coherence or detail-focused end of the continuum. A battery of 14 coherence measures was administered to over 200 typically developing (Tn) individuals, 31 individuals with ASD, and 31 age- and IQ-matched control participants. The pervasiveness of central coherence was tested across visuo-spatial and auditory/verbal domains, and high- and lowlevels of processing. Age and IQ were typically related to task performance in the TD group, but a large proportion of variance remained unexplained and may reflect cognitive style. Low-level tasks were associated within and across visual and auditory domains, suggesting some consistency in individual differences. High-level tasks did not show such consistency, suggesting that executive/strategic processes may have greater effect on task performance than local-global processing style. Males showed greater detail-focus and stronger developmental effects (more global with age) than females on several measures. Weak coherence was demonstrated in ASD by local processing bias and lack of global bias. Local and good global processing appeared to be more in trade-off in the ASD group than in TD and control groups. Good local processing related to IQ in TD and controls, but less so in ASD suggesting local bias is more automatic to individuals with ASD. Subgroups were determined on the basis of performance across the battery, according to whether local or global processing was dominant, or whether an individual adapted well or poorly to the demands of the task. A consistent local processing style was more common in the ASD group than in the control group, but was not universal The implications of these findings for weak central coherence theory of ASD are discussed.

Simple connections between structure and optical response empower us with essential intuition to engineer complex optical functionalities. In this thesis, I study photonic crystals, quasicrystals and amorphous materials to quantify the structural properties that give rise to photonic band gaps (PBGs). Along the way, I develop two novel perspectives on the optical analysis of arbitrarily-structured media: generalised photonic band structure and local self-uniformity (LSU). Generalised photonic band structures reproduce the Bloch-wave band structure of photonic crystals but, crucially, also yield naturally unfolded complete dispersion relations for aperiodic materials. Using generalised band structures, I demonstrate that the overall form of a material's dispersion relation is determined by the non-zero momentum transfers of its structure factor. I observe in great detail the fractal-like PBG spectra of a pair of Penrose photonic quasicrystals. Here, I demonstrate that, in most cases, the Penrose PBGs form through a mechanism of Bragg scattering-induced standing wave formation. The fundamental gap of each structure, however, is attributed to spatially localised scattering resonances. I also fabricate and characterise hyperuniform gold metasurfaces. Fluorescence emission characterisation reveals a statistically isotropic distribution of momentum states within the light cone; this property is shown to result from the metasurface structure factor. In the second part of this thesis I introduce LSU as a continuous measure of the extent to which a network possesses an optimal PBG-forming structure. Specifically, LSU measures the geometrical and topological similarities of the local vertex environments in a network of uniform valency. I demonstrate that both known optimal photonic crystal structures and disordered PBG-forming networks possess significant LSU. Further, I produce the first known designs of amorphous gyroid networks. Amorphous gyroids possess significant LSU and can exhibit a sizeable complete PBG; these PBGs are validated experimentally by performing microwave transmission experiments on centimetre-scale alumina prototypes (εr = 9:5 ± 0.3 at 22 GHz). Using ensembles of both amorphous gyroids and planar hyperuniform networks, I demonstrate the striking correlation between LSU and PBG-forming ability. I rationalise the success of LSU by advancing a picture of photonic tight binding in high index connected networks. This picture explains the origin of PBGs in both ordered and disordered connected networks, and suggests why the diamond architecture possesses the largest known PBG. To conclude, I explore the possibility that amorphous gyroids exist in the wing scales of butteries. I reveal that the microstructure in the scales of Pseudolycaena marsyas possesses substantial amorphous gyroid character and demonstrate that the buttery's reflectance spectrum can be effectively reproduced by amorphous gyroid microstructures.

Mucoadhesive drug delivery systems which are being used from 1980’s to avoid first pass metabolism of drugs, commercially exist for only systemic drug delivery with fast erosion times (15-60 min), that may not be appropriate for local oral disorders. The goal of this research was to develop and characterize mucoadhesive films with flexibility of carrying different drugs and proteins and provide sustained release for local treatment of oral disorders. Mucoadhesive films composed of polyvinylpyrrolidone (PVP) and carboxymethlycellulose (CMC) were formulated with imiquimod, an immune response modifier. Problems such as solubilization of imiquimod to increase drug loading, uniformity in films and total amount of drug released into supernatants were addressed by use of acetate buffer after investigating multiple methods. Subsequently, other relevant properties of mucoadhesive systems, such as adhesion (shear, pull-off), tensile properties, swelling profiles, transport kinetics, and subsequent changes in release profiles as a function of film composition were characterized. The potential of the system for local retention of imiquimod, determined in oral mucosa of hamsters showed time dependent decrease in imiquimod amount through 12 hours, with no traces of drug in blood. Further testing in humans revealed that the residence time of the mucoadhesive films depended on the application site, increasing in the order of tongue < cheek < gingiva. In parallel, mucoadhesive films loaded with epidermal growth factor (EGF) were developed to promote treatment of oral mucosal wounds. Bioactivity was tested in vitro on buccal tissues by creating a wound followed by application of films. Although EGF-loaded films did not accelerate wound healing, but rather elicited a hyperparakeratotic response. In vitro buccal tissues may not be appropriate for testing the effects of EGF in wound healing without incorporation of other biochemical factors. Overall, a mucoadhesive system capable of delivering bioactive small molecules and proteins in sustained manner was developed in this work. A thorough understanding of the system properties was achieved to further tune for future applications. In vitro studies and in vivo studies in hamsters and humans clearly showed the potential and usefulness of the system to translate in to clinic for treatment of oral precancerous lesions.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 148-158).
Many neurological disorders are now classified as circuit disorders, in which the underlying pathology arises from a failure in dynamic communication between anatomically distinct regions of the brain. Systemic therapies are often not effective due to their untargeted nature. The injectrode is a multifunctional probe designed to treat neurological disorders through targeted chemical and electrical stimulation directly to a focal point within the implicated neural circuit. This thesis details the characterization and biocompatibility of the injectrode for the treatment of neurological disorders on chronic timescales. In vitro and in vivo infusion tests were conducted to validate the ability to deliver nanoliter scale volumes (10-1000 n1) of drug to targeted brain structures over the course of an eight week implantation period. Muscimol was delivered to deep brain structures to demonstrate effective modulation of neural activity and behavior. These findings highlight the utility of a local chemical delivery approach to treat circuit diseases of the brain. Glial scar is a major barrier to neural probe function. A main objective of this thesis is focused on understanding the process of glial scar formation from a materials perspective. Micromotion and mechanical mismatch are thought to be key drivers of scar formation. This hypothesis was investigated using a novel 3D in vitro glial scar model, which replicates the magnitude and frequency of micromotions that are observed in vivo. Astrocytes were found to have a significant increase in cellular area and perimeter in response to micromotion compared to static control wells. These findings were applied to improve the biocompatibility of the injectrode. Hydrogel coatings, with moduli matched to brain tissue, were formed to mitigate the effects of micromotion. These coatings were found to reduce local strain by up to 70%. In vivo studies were conducted to explore the impact that implant diameter and modulus have on scar formation. Hydrogel coated implants (E=1 1.6 kPa) were found to significantly reduce scarring at 8 weeks post implantation, compared to uncoated implants (E=70 GPa). Size effects from increasing the overall implant diameter were also observed, highlighting the importance of considering both mechanical and geometric factors when designing chronic neural implants.
by Kevin C. Spencer.
Ph. D.

Mise en evidence, a temperature ambiante, de la substitution de rb**(+) a toute concentration. Determination par diffraction de neutrons sur poudre de la structure moyenne des cristaux mixtes : resultats en accord avec les resultats rpe. Puis, etude a basse temperature de l'ordre du sous-reseau des ions nh::(4)**(+) pour 0 ou= 0,25. Mise en evidence de l'apparition de domaines antiphase et determination de la distance moyenne entre les discommensurations. Enfin, interpretation du comportement a basse temperature de ce systeme d'ising axial aleatoire dans le cadre du verre de "pseudo-spin" structural

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Universidade Federal de Sao Carlos
Background: Musculoskeletal disorders have been recognized as a worldwide health problem. One of the measures for controlling these disorders is workplace exercise, either at the workstation or in a separate environment within the company. However, there is controversy regarding the effectiveness and means of applying these interventions. Objectives: To assess and provide evidence of the effectiveness of workplace exercise in controlling musculoskeletal pain. Methods: The following databases were searched: PubMed, MEDLINE, Embase, Cochrane, PEDro and Web of Science. Two independent reviewers selected the elegible studies. Possible disagreements were solved by consensus. All randomized controlled clinical trials that evaluated exercise interventions in the workplace musculoskeletal pain relief were included. The PEDro scale (range=0-10 points) was used to rate the quality of the studies included in this review. Results and Conclusion: The electronic search yielded a total of 8680 references published in English. At the end of the selection process, 18 studies were included. Strong evidence was found to support the effectiveness of physical exercise in controlling neck pain among workers who performed sedentary tasks in offices or administrative environments, while moderate evidence was found for low back pain relief among healthcare and industrial workers who performed heavy physical tasks. These positive results were reported when the training periods were longer than 10 weeks, the exercises were performed against some type of resistance and the sessions were supervised. None of the studies evaluating sedentary workers reported positive results for controlling musculoskeletal shoulder pain. Further randomized controlled trials are needed to comparatively evaluate, among other aspects, the effects of light and heavy training for shoulder pain relief.
As disfunções musculoesqueléticas representam um problema de saúde mundial. Dentre o conjunto de medidas para controle dessas alterações está a prática de exercício físico em ambiente ocupacional, que pode ser realizada no próprio setor de trabalho ou em ambientes à parte, mas dentro da empresa. Entretanto, há controvérsias quanto à efetividade e à forma de aplicação desse tipo de intervenção.Objetivos: Avaliar a efetividade e fornecer evidências a respeito da prática de exercício físico no ambiente ocupacional para o controle da dor musculoesquelética. Métodos: As seguintes bases bibliográficas foram consultadas: PubMed, MEDLINE, Embase, Cochrane, PEDro e Web of Science. Dois revisores independentes selecionaram os estudos pertinentes, e as eventuais discordâncias foram solucionadas por consenso. Foram incluídos no estudo os ensaios clínicos randomizados controlados que realizaram intervenção no local de trabalho envolvendo exercício e avaliaram a dor musculoesquelética. A escala PEDro, que tem pontuação de 0-10, foi utilizada para avaliação da qualidade dos estudos incluídos nesta revisão. Resultados e Conclusões: A busca eletrônica resultou em um total de 8680 referências publicadas em inglês. Ao final do processo de seleção, 18 estudos foram incluídos. Forte evidência foi encontrada para a efetividade do exercício físico no controle de dor cervical em trabalhadores que realizavam atividades em escritórios ou setores administrativos, descritos como sedentários enquanto evidência moderada foi encontrada para a região lombar daqueles que realizavam atividades envolvendo manuseio de pacientes ou materiais na indústria, desde que os treinamentos fossem aplicados por períodos superiores a dez semanas, incluíssem exercícios realizados com algum tipo de resistência e fossem supervisionados. Nenhum estudo avaliando trabalhadores sedentários relatou resultados positivos para o controle da dor musculoesquelética em ombros. Novos estudos randomizados controlados são necessários para avaliar, dentre outros aspectos, o efeito comparado de treinos leves e pesados para ombros.

Orientador: Eduardo Miranda
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin.
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Resumo: O objetivo deste trabalho é estudar os efeitos da desordem nas proximidades da transição metal-isolante de Mott. Para tanto, utilizamos o modelo de Hubbard desordenado em duas dimensões. A teoria que aplicamos para estudar esse modelo é a Teoria Estatística Dinâmica de Campo Médio, que trata de maneira não-trivial os efeitos de desordem e interação elétron-elétron. A aproximação básica da teoria consiste em descrever os efeitos de interação de maneira local. Nela mapeamos o nosso problema original em vários problemas de uma impureza de Anderson, embebidos em banhos que são determinados através de uma condição de autoconsistência. Esses problemas são resolvidos no nosso trabalho aplicando o método do Monte Carlo Quântico, algoritmo Hirsch-Fye, que faz cálculos em temperatura finita. No nosso estudo conseguimos observar a coexistência de soluções metálicas ruins e isolantes ruins num mesmo sistema, para temperaturas um pouco maiores do que a que determina o ponto crítico da transição de Mott. Relacionamos a condutividade local com as energias locais desordenadas, observando que essas energias funcionam como um potencial químico dependente do sítio que altera localmente a dopagem do sistema. Finalmente, verificamos o aumento do valor da interação crítica com a desordem. Esse trabalho é a primeira implementação numérica da Teoria Estatística Dinâmica de Campo Médio com Monte Carlo Quântico, que é o estado da arte de cálculos de sistemas de uma impureza única. Nesse sentido, nosso trabalho representa um importante primeiro passo na implementação do método e fornece um paradigma inicial do seu poder e das suas limitações.
Abstract: The main goal of this work is to study the effects of disorder in the proximity of a Mott metal-insulator transition. For that, we use the disordered Hubbard model in two dimensions. The theory we aply to study this model is the Statistical Dynamical Mean Field Theory, which treats the effects of disorder and electron-electron interactions in a non-trivial fashion. The basic aproximation of that theory is to describe the effects of interactions in a local way. In this theory we map the original system in several Anderson single-impurity problems, embebbed in baths that are determined through a self-consistency condition. These problems are solved in our work through the Quantum Monte Carlo method, with the Hirsch-Fye algorithm, at finite temperature. In our study, we found the coexistence of bubbles of bad metal and bad insulator in the same system, for temperatures a little higher than that which determines the critical point of the Mott transition. We could relate the local conducting properties with the local disordered energies, finding that these energies work like a site-dependent chemical potential which changes locally the doping of the system. Finally, we verified the enhancement of the critical interaction by disorder. This work is the first numerical implementation of the Statistical Dynamical Mean Field Theory with the Quantum Monte Carlo, which is the state of art for calculations of single-impurity systems. In this sense, our work is an important first step in the implementation of the method and sets a preliminary benchmark of its power and limitations.
Mestrado
Física da Matéria Condensada
Mestre em Física

Specialist Resource Provisions (SRPs) are unique types of educational provision providing a specialist classroom environment with access to a mainstream school setting. This research was set up to investigate the SRPs for children with Autistic Spectrum Disorders (ASD) within a Local Authority. A literature review revealed there is limited research specifically looking at the effective inclusion of children with ASD in SRPs. Previous research around education and ASD has tended to focus on the mainstream versus special school debate and what factors led to effective inclusion in these separate settings. This research study sought to evaluate which factors facilitated the effective inclusion of pupils, what barriers were faced to inclusion, what were parental and pupil perspectives, what were the characteristics of pupils whose needs could not be meet in the current SRPs and how the SRPs could be developed further to meet a wider range of pupil needs. The research used an exploratory qualitative approach collecting data through a focus group, a semi-structured interview and questionnaires with different groups of stake holders. Data was analysed using a content analysis approach with the support ofMAXQDA to support the analysis process. The main findings showed that there is a need for: • effective communication and links with others • regular access to external support services • access to an academic and alternative curriculum • ongoing training for all staff and peers • an appropriate physical environment • flexible staffing and funding arrangements The pupil characteristics that were hardest to meet with an SRP environment related to: • emotional and behavioural difficulties 1 1 2 • sensory needs • severe learning difficulties • severe speech and language difficulties • severe interaction difficulties The results were discussed in relation to future developments for the SRPs and the role of the Educational Psychologist in supporting SRPs.

Syftet med denna studie var att jämföra tre års resultat av enbart lokalanestesi jämfört mot lokalanestesi ochspolning i käkledenpå patienter som lider av smärtande diskdisplacering utan reduktionStudien utfördes från 2003 till 2007 och 45 patienter valdes från sammanlagt 55 utvalda patienter för behandling av TMD till avdelningen för Klinisk bettfysiologi, Odontologiska fakulteten, Malmö högskola, Sverige.Frågeformulär och klinisk undersökning enligt Research Diagnostic Criteria(RDC/TMD), panorama röntgenbilder och magnetisk resonanstomografi utfördes vid start av studien. Tre år efter behandling, sändes ett frågeformulär till 37 patienter.Intensiteten av smärta, fysisk funktion, känslomässig funktion och global förbättring utvärderades.Tjugofyra patienter randomiserades till behandling med lokalanestesi och tjugo patienter randomiserades till behandling med lokalanestesi och spolning. Trettiofyra patienter besvarade enkäten vid 3-års uppföljningen. I en intention-to-treat analys visade det huvudsakliga resultatet att 28/45(62%) hade fått 30% smärtlindring vid uppföljningen. Inga signifikanta skillnader fanns mellan grupperna lokalanestesi och lokalanestesi och spolning avseende smärtlindring, fysisk funktion, känslomässig funktion och global förbättring. Det fanns signifikanta förbättringar (P< 0.05) inom båda grupperna avseendesmärtintensitet, fysisk funktion och emotionell funktion och global förändring vid uppföljning jämfört med start av studien.Eftersom det inte fanns någon skillnader mellan grupperna lokalanestesi och spolningoch enbart lokalanestesii käkleden tre år efter behandling av smärtsam diskdisplacering utan återgång, kan spolning av käkleden ifrågasätts.
The aim of this prospective and longitudinal study was to compare three-year outcomes of local anesthetics compared to anesthetics, arthrocentesis and lavage on patients suffering from painful jaw locking in the TMJThe study was performed from 2003 until 2007 and 45 patients were selected from altogether 55 eligible patients referred for the treatment for TMD to the Department of Stomatognathic Physiology, Faculty of Odontology, Malmö University, Sweden. History questionnaire and clinical examination according toResearch Diagnostic Criteria, panoramic radiographs and Magnetic Resonance Imaging were completed at baseline. A questionnaire was sent three years after treatment to 37 patients. Pain intensity, physical functioning, emotional functioning and global improvement were evaluated.Twenty-five patients were randomised to group anesthetics and 20 patients were randomised to group anesthetics, arthrocentesis and lavage. Thirty-four patients answered the questionnaire at the 3-year follow-up. In an intention-to-treat analysis the primary outcome, showing a ≥30% pain relief, was reported by 28 of 45(62%) patients at the follow-up. No significant differences in improvement were found between group local anesthetics and group anesthetics, arthrocentesis and lavage regarding pain relief, physical functioning, emotional functioning, and global improvement. Significant improvements(P<0.05) were found within both groups regarding pain intensity, physical functioning, emotional functioning and global changes at the follow-up compared to baseline.Since no differences were found between local anesthetics, arthrocentesis and lavage compared to local anesthetics alone of the TMJ three years after treatment of painful disc displacement without reduction, the use of arthrocentesis and lavage can be questioned.

Orientador: Keila Miriam Monteiro de Carvalho
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Objetivo: Avaliar os resultados da cirurgia monocular na correção de estrabismos horizontais de grande ângulo sob anestesia peribulbar. Métodos: Foram avaliados 92 pacientes submetidos à cirurgia monocular de estrabismo horizontal de grande ângulo (ângulo igual ou superior a 40 dioptrias prismáticas - DP) sob anestesia peribulbar no Hospital das Clínicas/UNICAMP. Os pacientes foram divididos em dois grupos: grupo 1 ¿ esotropias e grupo 2 ¿ exotropias. A cirurgia constava de retrocesso e ressecção dos retos horizontais no olho não dominante. O seguimento pós-operatório foi de 6 meses, quando foram avaliados o desvio residual e a movimentação ocular. Foi considerado como sucesso cirúrgico um desvio residual de até 15 DP. Em casos de desvios maiores que 15 DP, um segundo procedimento era indicado. Resultados: Em todos os pacientes com desvio de até 60 DP foi alcançado sucesso cirúrgico. Nos pacientes com desvio de 65 DP, a cirurgia teve sucesso em 1 de 3 pacientes do grupo 1 e em 5 de 9 pacientes do grupo 2 . Em desvios superiores a 65 DP, todos apresentaram desvios residuais maiores que 15 DP. Destes, 13 pacientes se submeteram a um segundo procedimento e, em todos, houve sucesso cirúrgico. A Análise da Curva ROC mostrou o ponto de corte do desvio pré-operatório para obter sucesso cirúrgico, que foi de 62,5 DP. Nenhum paciente apresentou limitação importante da movimentação ocular. Não houve complicações cirúrgicas ou anestésicas. Conclusões: A cirurgia monocular pode ser uma opção para correção de estrabismos horizontais de grande ângulo, sob anestesia peribulbar, até desvios entre 60 e 65 DP. Acima de 65 DP, a cirurgia monocular não foi suficiente para se obter sucesso pós-operatório
Abstract: Purpose: Evaluate the results of monocular surgery for large-angle horizontal strabismus under peribulbar anesthesia. Methods: Ninety-two patients submitted to monocular surgery under peribulbar anesthesia for large-angle horizontal strabismus (angle of 40 prism dioptre or greater) in Clinical Hospital of State University of Campinas were evaluated. The patients were divided into group 1 ¿ esotropias and group 2 - exotropias. The surgery consisted of recession and resection procedures of the horizontal rectus. The postoperative follow-up was of 6 months, when it was evaluated the resisual deviation and the ocular movement. A residual deviation until 15 PD was considered a successful result. In cases of residual deviation over 15 PD, a second procedure was indicated. Results: In all patients until 60 PD preoperative deviations, successful surgery results were achieved. In the patients with 65 PD preoperative deviations, successful surgery results were obtained in 1 of 3 patients in group 1 and in 5 of 9 patients in group 2. All patients with deviations over 65 PD presented residual deviation over 15 PD. Thirteen patients were submitted to a second procedure. Successful results were obtained in all of them. The ROC Curve Analysis showed the cut point to get a successful surgery result: 62,5 PD. No patient presented important limitation of the ocular movement. There were no complications from surgery or anesthesia. Conclusions: The monocular surgery can be an alternative for horizontal large-angle strabismus under peribulbar anesthesia until deviations between 60 and 65 PD. In the deviations over 65 PD, the monocular surgery did not achieve successful results
Mestrado
Oftalmologia
Mestre em Ciências Médicas

Mesoporous alumina (Al2O3) in the gamma (γ) phase is widely used as a support in catalytic applications because of its high surface area, large pore volume, acid-base characteristics, and thermal stability. To improve the thermal stability of gamma alumina, dopants such as lanthanum, magnesium, zirconia, and silica are often introduced. Current laboratory-based methods for synthesizing gamma alumina generally involve 10-15 steps and/or use toxic, expensive surfactants and solvents. Industrial methods, while simpler, lack control of pore properties and surface chemistry. In contrast, we have developed an innovative solvent deficient, one-step method that is able to synthesize a wide range of pure and silica-doped aluminas with high surface areas, pore volumes from 0.3 to 1.8 cm3/g, and pore diameters from 5 to 40 nm. More significantly, our silica-doped aluminas are stable up to temperatures as high as 1300<°>C, which is 200<°>C higher than other pure and doped gamma alumina materials.The usefulness of gamma-alumina as a catalyst support is dependent on its favorable combination of textural, thermal, structural, and chemical properties, yet the relationship between structure and these other properties is still not clearly understood due to the poorly crystallized nature of the material. In particular, the mechanism by which the gamma structure is stabilized thermally by so many dopants is still not well understood. Based on our previous PDF experiments on pure and La-doped alumina, we have developed a hypothesis regarding the mechanism by which dopants increase thermal stability. To validate or refute this hypothesis, we collected PDF data on a wider range of laboratory and industrial alumina samples. Herein, we have utilized PDF analysis to study the local to intermediate-range structure of a series of our pure and silica-doped aluminas calcined at 50<°>C intervals between 50 and 1300<°>C as well as pure and silica-doped aluminas from commercial sources and other synthetic methods. This thorough study of alumina local structure will allow us to separate general trends in the local structure from idiosyncrasies based on synthetic method/conditions, and it will help us identify the structural features responsible for improved thermal stability. Having access to these PDF experiments, we have validated our current hypothesis on the nature of stabilization afforded by dopants and, more generally, developed a better understanding of the role structure plays in the properties of aluminas.

Apesar das lesões músculo-esqueléticas ligadas ao trabalho (LMELT) se encontrarem entre as doenças profissionais mais prevalentes nos higienistas orais (HO), não se conhece nenhum estudo que avalia esta problemática nos profissionais Portugueses. O presente estudo investigou a prevalência de sintomas de LMELT nos higienistas orais, procurando relações com as actividades mais frequentes. Um questionário de auto-preenchimento foi distribuído a 415 HO obtendo-se uma taxa de resposta de 61,2%. Os sintomas de LMELT mais referidas estão ao nível do pescoço (52%), punho/mão (47,8%), zona dorsal (45,2%), lombar (44,5%) e ombro (40,9%). Apesar de existirem algumas associações significativas ao nível da parte superior do corpo, somente a variável género apresentou associação significativa forte com a variável ―qualquer sintoma em qualquer localização‖ (p=0,001). Este estudo sugere que as LMELT são um problema entre os higienistas orais portugueses. Mais estudos serão necessários para melhor compreender esta problemática e estabelecer estratégias preventivas que ajudem a minimizar o seu impacto; ABSTRACT: Despite work-related musculoskeletal disorders (WRMSDs) are among the most prevalent occupational diseases between dental hygienists (DH), any known study have explored this problem in the Portuguese professionals. The present study investigated the prevalence of WRMSDs symptoms in dental hygiene professionals, looking for relationships with the most frequent activities. A self-reporting questionnaire was distributed to 415 DH from which a response rate of 61,2% was achieved. The WRMSDs symptoms most commonly reported are at the neck (52%), hand/wrist (47,8%), upper back (45,2%), lower back (44,5%) and shoulder (40,9%) regions. Although there are some significant associations in the upper body, only gender revealed a significant association with the presence of ―any symptom in any body location‖ (p=0,001). Overall, this study suggests that WRMSDs are a common problem among dental hygienists in Portugal. As such, further studies are required to better understand this problem and to establish preventive strategies that minimize its impact.

L'objectif de cette thèse est de mener une étude fondamentale et expérimentale des propriétés physiques des cristaux liquides discotiques colonnaires (CLDCs) confinés dans des matrices poreuses templates hautement ordonnées à l'échelle nanométrique. Les molécules des CLDCs de forme plane, composées de noyaux polyaromatiques rigides entourées de chaînes aliphatiques flexibles fonctionnalisables, sont susceptibles de s'auto-assembler dans des colonnes favorisant ainsi le recouvrement de leurs orbitales électroniques π. Ce qui fait de ces matériaux de véritables candidats pour des applications dans l'électronique moléculaire et la photovoltaïque grâce à la possibilité de migration des porteurs de charges le long de leurs colonnes. Cependant, ces applications nécessitent une bonne maîtrise des paramètres influant sur les mécanismes d'alignement dans les phases colonnaires, sur de grands monodomaines, et de préférence à température ambiante. Une méthode très prometteuse visant à optimiser les longueurs de diffusion des porteurs de charge a été récemment proposée, basée sur la formation de nanofils orientés de CLDCs par auto-assemblage dans des matrices dites " templates " (de moulage). Toutefois, les propriétés structurales, dynamiques et les effets de confinement sur ces technologies restent aujourd'hui mal connus et morcelés et pourraient constituer un véritable verrou scientifique pour leur réalisation. Notre étude s'est portée sur les CLDCs commerciaux (HPT) et le Py4CEH (moins connus) qui sont confinés dans des alumines poreuses (AAO) et du silicium poreux (Sip) de diamètres de pores de quelques dizaines de nm. Les diagrammes de phase ont été d'abord étudiés par DSC puis les effets structuraux ont été approfondis grâce à la diffusion de neutrons. Dans les géométries confinées, nous observons une dépression des températures de transition, un élargissement du domaine de stabilité de la phase colonnaire et l'ouverture d'une hystérèse amplifiée dans les pores de plus petite taille. Un ordre orientationnel très élevé a été trouvé dans les phases colonnaires bulk par la RMN du solide et la structure des systèmes confinés colonnaires, dominée par une distribution radiale avec un ancrage homéotrope a été déterminée. La dynamique moléculaire a été étudiée par diffusion quasiélastique de neutrons. Elle est affectée par le confinement : la dynamique de grande amplitude est fortement ralentie, tandis que la dynamique rapide locale devient régie par une distribution très large de temps caractéristiques.

Este estudo foi concebido com o objetivo de avaliar os efeitos de um programa de exercícios no local de trabalho sobre a flexibilidade e a percepção de dor musculoesquelética entre trabalhadores de escritório, e sua relação com a freqüência semanal de participação. Quarenta e nove funcionários de escritório de uma empresa do setor farmacêutico localizada na cidade de São Paulo foram distribuídos randomicamente em três grupos, de acordo com o número semanal de sessões propostas: duas (RG2), três (RG3) e cinco (RG5) vezes por semana, respectivamente. O programa incluiu sessões de exercícios de 10 minutos compostas por alongamento, resistência muscular localizada, automassagem, massagem e técnicas de relaxamento, por um período de seis meses. Durante o período do programa também foram realizadas três palestras para os participantes com informações sobre exercícios no local de trabalho, atividade física e postura corporal. Para avaliar a flexibilidade de punhos e coluna cervical foi utilizado um inclinômetro de dupla escala e o teste do Terceiro Dedo ao Chão para avaliar a flexibilidade da coluna lombar. A versão curta do Inventário para Dor de Wisconsin foi utilizada para avaliar a percepção de dor musculoesquelética. As avaliações foram realizadas no início do programa (M0) e após três (M3) e seis meses (M6). O teste de Kolmogorov-Smirnov foi aplicado para testar a normalidade das variáveis quantitativas. A ANOVA bifatorial com teste de Tukey foi utilizada como método de comparação múltipla para avaliar diferenças das distribuições normais. Estatísticas para o teste do Terceiro Dedo ao Chão e intensidade de dores corporais foram obtidas pela ANOVA de Friedman e teste de Wilcoxon, respectivamente. Após a análise dos dados verificouse que houve aumento significativo nos valores de flexibilidade de cervical e lombar e punhos para todos os grupos randomizados. O grupo RG5 apresentou a mais significante redução na intensidade de dor relatada. Este estudo demonstrou que a participação em um programa de bem estruturado de exercícios no local de trabalho pode contribuir para o aumento da flexibilidade e para a redução da intensidade de dores musculoesqueléticas.
This study was designed to evaluate the effects of a workplace exercise program on flexibility and perception of muscular pain among office workers, and their relationship with the weekly frequency of participation. Forty nine office employees from a pharmaceutical company in the city of Sao Paulo were randomized into three groups according to the number of proposed weekly sessions: twice (RG2), three (RG3) and five (RG5) times respectively). The program included 10 minutes exercise sessions of stretching, resistance training, self-massage, massage and relaxation techniques for a six-month period. Participants also took part in three short lectures during the period of the program. A dual-scale inclinometer was used to measure wrist and cervical spine flexibility and the fingertip-to-floor test was used to estimate the low back range of flexibility. The short version of the Wisconsin Brief Pain Questionnaire was used to assess muscular pain perception. Evaluations were carried out at Baseline (M0), and after 3 (M3) and 6 (M6) months. Kolmogorov- Smirnov test was applied to test normality of quantitative variables. TWO-WAY ANOVA with Tukeys test was used as a multiple comparison method to evaluate differences over time for normal distributions. Statistics for the fingertip-to-floor test and body pain intensity were obtained by ANOVA and Friedman and Wilcoxon test, respectively. Data demonstrated statistically significant improvement in flexibility of the cervical and lumbar spine and wrists in all groups of randomization. The RG5 presented the most significant decrease of reported pain intensity. This study demonstrated that participating in a well-structured workplace program of physical exercises may contribute to improve flexibility and decrease the musculoskeletal pain intensity.

Utiliser des milieux nanostructurés pour confiner la lumière permet d'augmenter l'interaction entre un émetteur et le rayonnement électromagnétique. Dans cette thèse, nous utilisons un formalisme classique (présenté au Chap. 1) pour décrire cette interaction dans différents contextes, qui peuvent être regroupés en deux parties (respectivement Parties II et III).
Dans un premier temps, nous étudions l'apparition de modes localisés en champ proche de structures complexes. Nous nous intéressons à deux différents types de structures: des nanoantennes d'or et des films d'or désordonnés. Nos résultats nous permettent de discerner les modes radiatifs et non-radiatifs. Nous introduisons le concept de Cross Density Of States (CDOS) pour décrire quantitativement la cohérence spatiale intrinsèque associée à la structure modale d'un milieu complexe. Nous démontrons ainsi une réduction de l'extention spatiale des modes au voisinage de la percolation électrique des films d'or désordonnés.
Nous nous intéressons ensuite à des milieux fortement diffusants. En éclairant de telles structures par une source cohérente, on obtient une figure d'intensité complexe appelée speckle. Nous utilisons une méthode diagrammatique pour démontrer une corrélation négative entre les figures de speckle réfléchie et transmise à travers une tranche dans le régime mésoscopique. Nous nous intéressons ensuite à la corrélation C0, qui apparait lorsque la source est enfouie dans le milieu. Nous proposons une démonstration générale de l'égalité entre la corrélation C0 et les fluctuations normalisées de la LDOS, et soulignons le rôle fondamental des interactions de champ proche. Finalement, nous observons numériquement le régime de couplage fort entre un diffuseur résonnant et un mode localisé d'Anderson au sein d'un milieu désordonné 2D.

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Introdução: O uso de álcool está relacionado a acidentes de trabalho e à piora na saúde do indivíduo por isso torna-se relevante investir em programas de prevenção no ambiente laboral. Objetivos: Avaliar os efeitos da IB no ambiente de trabalho para problemas relacionados ao consumo de álcool. Método: Trata-se de um ensaio clínico randomizado não controlado, com desenho quase experimental de natureza quantitativa. O estudo contou com 120 participantes que receberam diferentes estratégias de acordo com o AUDIT: Educação para o álcool (0 a 7 pontos); Aleatorização para os grupos 01 e 02 (08 a 19 pontos) – (O grupo 01 recebeu feedbacks e panfletos e o grupo 02 recebeu feedback, panfletos e a IB); Encaminhamento para especialistas (20 pontos ou mais). Houve follow up via telefone após três meses para os grupos 01 e 02. Resultados: Houve uma boa taxa de adesão a pesquisa, o grupo 02 (IB) mostrou diferenças significativas na redução do consumo de álcool e no grupo 01 estas diferenças não foram significativas apesar de os dois grupos sinalizarem tendências para a redução do consumo. Conclusão: A aplicação da IB no ambiente de trabalho foi viável, porém novas pesquisas são necessárias a fim de comprovar a eficácia e efetividade da IB no ambiente organizacional.
Introduction: The use of alcohol in workplace causes accidents and worsening health of the individual therefore is relevant to invest in prevention programs in the workplace. Objectives: Evaluate the effects of Brief Intervention in the workplace for problems related to alcohol consumption. Method: The research is a randomized clinical trial, not controlled, quasiexperiment and quantitative study. The study included a total of 120 participants. According to the AUDIT score were applied different strategies: Education for alcohol (0-7 points); Randomization for groups 01 and 02 (08-19 points) - The group 01 received feedback on the AUDIT score and brochures and the group 02 received feedback from the AUDIT, brochures and also BI. Were referred to a specialist employees who achieved a score between 20 and 40 points. There were follow up via phone after three months for groups 01 and 02. Results: There was a good research membership fee and the group 02 (BI) showed significant differences in the reduction of alcohol consumption and in group 01 these differences were not significant despite the two groups to signal trends to reduce consumption. Conclusion: The implementation of the BI in the workplace was feasible but further research is needed to prove efficiency and effectiveness of BI in the workplace.

Proteins are involved in numerous functions in the human body, including chemical transport, molecular recognition, and catalysis. To perform their function most proteins must adopt a specific structure (often referred to as the folded structure). A microscopic description of folding is an important prerequisite for elucidating the underlying basis of protein misfolding and rational drug design. However, protein folding occurs on heterogeneous length and time scales, presenting a grand challenge to both experiments and simulations. In computer simulations, challenges are generally mitigated by adopting coarse-grained descriptions of the physical environment, employing enhanced sampling strategies, and improving computing code and hardware. While significant advances have been made in these areas, for numerous systems a large spatiotemporal gap between experiment and simulations still exists, due to the limited time and length scales achieved by simulation, and the inability of many experimental techniques to probe fast motions and short distances. In this thesis, kinetic transition networks (KTNs) are constructed for various protein folding systems, via approaches based on the potential energy landscape (PEL) framework. By applying geometry optimisation techniques, the PEL is discretised into stationary points (i.e.~low-energy minima and the transition states that connect them). Essentially, minima characterise the low-lying regions of the PEL (thermodynamics) and transition states encode the motion between these regions (dynamics). Principles from statistical mechanics and unimolecular rate theory may then be employed to derive free energy surfaces and folding rates, respectively, from the KTN. Furthermore, the PEL framework can take advantage of parallel and distributed computing, since stationary points from separate simulations can be easily integrated into one KTN. Moreover, the use of geometry optimisation facilitates greater conformational sampling than conventional techniques based on molecular dynamics. Accordingly, this framework presents an appealing means of probing complex processes, such as protein folding. In this dissertation, we demonstrate the application of state-of-the-art theory, combining PEL analysis and KTNs to three diverse protein systems. First, to improve the efficiency of protein folding simulations, the intrinsic rigidity of proteins is exploited by implementing a local rigid body (LRB) approach. The LRB approach effectively integrates out irrelevant degrees of freedom from the geometry optimisation procedure and further accelerates conformational sampling. The effects of this approach on the underlying PEL are analysed in a systematic fashion for a model protein (tryptophan zipper\,1). We demonstrate that conservative local rigidification can reproduce the thermodynamic and dynamic properties for the model protein. Next, the PEL framework is employed to model large-scale conformational changes in proteins, which have conventionally been difficult to probe in silico. Methods based on geometry optimisation have proved useful in overcoming the broken ergodicity issue, which is associated with proteins that switch morphology. The latest PEL-based approaches are utilised to investigate the most extreme case of fold-switching found in the literature:~the α-helical hairpin to β-barrel transition of the C-terminal domain of RfaH, a bacterial transcription factor. PEL techniques are employed to construct the free energy landscape (FEL) for the refolding process and to discover mechanistic details of the transition at an atomistic level. The final part of the thesis focuses on modelling intrinsically disordered proteins (IDPs). Due to their inherent structural plasticity, IDPs are generally difficult to characterise, both experimentally and via simulations. An approach for studying IDPs within the PEL framework is implemented and tested with various contemporary potential energy functions. The cytoplasmic tail of the human cluster of differentiation 4 (CD4), implicated in HIV-1 infection, is characterised. Metastable states identified on the FEL help to unify, and are consistent with, several earlier predictions.

The temporomandibular myofascial pain presents a major challenge in the diagnosis of temporomandibular disorders. Due to the characteristics of this condition, intramuscular injection procedures are often needed for adequate control of symptoms and treatment. Thus, the aim of this study was to evaluate the effectiveness of injection with different substances or dry needling in temporomandibular myofascial pain. The study design consisted of a systematic review of randomized clinical trials and research databases consulted were: Pubmed, EMBASE, CENTRAL/Cochrane, Lilacs, Scopus and Web of Science until October 2014. The selection of studies was carried out by two independent reviewers, who applied eligibility criteria to obtain the final sample of primary studies. After application of the inclusion criteria were selected fifteen studies. Due to the heterogeneity of the primary studies it was not possible to perform a meta-analysis. The narrative analysis of the results showed that most of the studies had methodological limitations and biases that have compromised the quality of its findings. Thus, there is a need of conducting further randomized clinical trials, with follow-up and larger samples, to evaluate the real effectiveness of the technique and evaluated substances.
A dor miofascial temporomandibular apresenta um grande desafio diagnóstico dentro das Disfunções Temporomandibulares. Devido às características dessa condição, procedimentos de infiltração intramuscular muitas vezes são necessários para o adequado controle e tratamento dos sintomas. Assim, o objetivo desse estudo é avaliar a efetividade de infiltrações com diferentes substâncias ou agulhamento à seco em dor miofascial temporomandibular. O delineamento do estudo consistiu em uma revisão sistemática de ensaios clínicos randomizados e as bases de pesquisa consultadas foram: Pubmed, EMBASE, CENTRAL/Cochrane, Lilacs, Scopus e Web of Science no período até outubro de 2014. A seleção dos estudos foi realizada por dois avaliadores independentes, que aplicaram critérios de elegibilidade para a obtenção da amostra final de estudos primários. Após a aplicação dos critérios de inclusão quinze estudos foram selecionados. Devido à heterogeneidade dos estudos primários não foi possível realizar uma meta-análise. A análise narrativa dos resultados mostrou que a maioria dos estudos apresentava limitações metodológicas e vieses que comprometeram a qualidade de seus achados. Assim, existe a necessidade da condução de novos ensaios clínicos randomizados, com tempo de acompanhamento e amostras maiores, para avaliar a real efetividade da técnica e das substâncias avaliadas.

La surdité et les troubles vestibulaires sont des pathologies fréquentes, source de handicap et d’altération de la qualité de vie. Actuellement, il n’existe pas de traitement curatif pour ces pathologies. La thérapie génique utilisant les AAVr semble une alternative prometteuse notamment dans le traitement des surdités et troubles vestibulaires d’origine génétique. Cependant, de nombreux défis restent à relever avant d’envisager une application chez l’Homme. Dans ce travail, nous avons cherché à identifier les étapes clés à franchir pour une application clinique de la thérapie génique pour 2 surdités génétiques humaines, le syndrome USH1G et la surdité DFNB9, à l'aide des modèles murins correspondants, d'études chez le primate non-humain et d'un modèle d’explant d’organes vestibulaires humains. Nous avons pu montrer que la fenêtre thérapeutique était un facteur majeur à prendre en compte dans un objectif translationnel. Le stade de maturation de l’oreille interne influe grandement sur l’efficacité de la thérapie, d’autant plus lorsque la pathologie implique des anomalies de développement comme dans le syndrome USH1. Pourtant, nous avons pu apporter la preuve d’une extension de la fenêtre thérapeutique chez la souris Ush1g-/-, et montrer que la thérapie génique permettait une restauration à un niveau proche de la normale de la fonction vestibulaire et dans une moindre mesure de la fonction auditive après injection à un stade mature. Dans la surdité DFNB9 pour laquelle il n’existe pas d’anomalie de développement, nous avons pu montrer que la thérapie génique permettait une restauration complète de l’audition, et posé les fondements d’une future thérapie chez l’Homme
Deafness and vestibular disorders are frequent pathologies, and sources of disability and impaired quality of life. Deafness is the most common sensory disorder in humans, and 1 child is born deaf for every 700 births. Currently, there is no cure for these disorders. A promising therapeutic alternative is gene therapy using rAAV, and numerous preclinical studies have provided proof of its efficacy in the treatment of deafness and vestibular disorders of genetic origin. However, many challenges remain to be overcome before considering application in humans. In this work, we sought to identify the key steps to be taken for a clinical application of gene therapy for 2 human genetic causes of deafness, USH1G syndrome and DFNB9 deafness. We used the corresponding mouse models for this, as well as studies in non-human primates and an in vitro human vestibular organ explant model. We were able to show that the therapeutic window was a major factor to take into account in a translational objective. The stage of maturation of the inner ear greatly influences the effectiveness of therapy, especially when the pathology involves developmental abnormalities such as in USH1 syndrome. However, we were able to provide evidence of an extension of the therapeutic window in Ush1g-/- mice, and to show that viral gene therapy performed at a mature stage allowed vestibular function to be restored to a level close to normal, and to a lesser extent a restauration of hearing function. In DFNB9 deafness for which there is no developmental abnormality, we were able to show that gene therapy allowed a complete restoration of hearing, and laid the foundations for a future therapy in humans

Cette these est faite de deux parties independantes. La premiere partie traite les corrections quantiques a l'effet hall anormal. On peut montrer que les termes de l'anomalie coulombienne se compensent mutuellement en considerant la diffusion asymetrique des electrons de conduction par les moments magnetiques d'une couche metallique desordonnee. La contribution venant de la localisation faible est coupee par la diffusion asymetrique qui brise la coherence de phase. Les resultats sont en bon accord avec une experience recente sur des couches minces de fer desordonnees et ferromagnetiques. Dans la seconde partie, on etudie la formation de moments magnetiques localises dans des systemes comme des semiconducteurs dopes en phase metallique. Le calcul est base sur le modele de hubbard avec desordre hors-diagonal. En examinant le modele a une seule impurete faiblement rattachee au reseau, on trouve un moment magnetique localise, et cela meme dans l'approximation de hartree-fock pour la repulsion locale u. On associe a ce moment magnetique un effet kondo dont la nature et la dependance par rapport au desordre sont discutees. Les resultats sont compares a une experience recente mesurant le pouvoir thermoelectrique du si:p. La correspondance est satisfaisante

An ongoing debate is whether people with autism spectrum disorder (ASD) have a local processing bias and to what extent impaired contextual processing is associated with this bias. The set of experiments employed in this project examined global and local processing, shifts between global and local processing, and low- and high-level visual processing in an attempt to address this issue. This thesis tested the hypotheses that (1) a local processing bias is associated with impaired global processing in ASD individuals, and (2) atypical processing style is linked with ASD severity. Twenty ASD individuals and 20 IQ and age (15-30 years) matched normal controls were administered a novel embedded figures task (local processing advantageous), a novel form matching task and novel shape integration task (global processing advantageous), a local-global switching task (which assessed attention broadening and attention narrowing ability), and a local and global motion detection task. The Social Responsiveness Scale was used to assess ASD severity. The ASD group correctly detected significantly more embedded shapes than controls. Compared to controls, ASD participants were disproportionately slower on the shape integration task relative to the form perception task. No overall group differences were found in attention broadening or attention narrowing ability. In addition, no group differences were found in local or global motion perception. Results also revealed a significant correlation between ASD severity and (1) faster response time on the embedded figures test, (2) slower response time on the shape integration task, (3) reduced attention broadening ability, and (4) reduced global motion perception. These findings confirm previous reports of enhanced local visual processing in ASD, and suggest that while global form perception is intact in ASD, global integration is more problematic. There was no evidence of generalized attentional impairments or motion perception abnormalities in ASD participants, suggesting that lower-level perceptual functions may be spared in people with ASD. Perhaps most intriguing was the observed association between ASD severity and enhanced local perception and impaired global processing. This association suggests that both a local processing bias and impaired global processing may play a role in the behavioral aspects of ASD symptomatology.