Laser Directed Energy Deposition of an AlMgScZr-Alloy in High-Speed Process Regimes

Aluminum-magnesium-scandium-zirconium (AlMgScZr) alloys need to be rapidly cooled from the liquid state to obtain a high degree of solute supersaturation that helps to exploit the precipitation hardening potential of the material. While AlMgScZr alloys have been successfully used in laser powder bed fusion (LPBF) processes, there has been little research in the field of laser directed energy deposition (DED) of the material. The limited previous studies have shown that the performance of AlMgScZr parts fabricated with DED only reached about 60% of that of the parts fabricated with LPBF. In view of breaking through the limitation associated with the process conditions of conventional DED, this work demonstrates the DED of AlMgScZr alloys in high-speed process regimes and elucidates the mechanism of enhancing the hardness and tensile strength of AlMgScZr alloys by increasing the cooling rate by one to two orders of magnitudes, as well as reducing the track overlapping and the porosity of the specimens during the process. A maximum average hardness of nearly 150 HV0.1 and a max. tensile strength of 407 MPa are obtained by using an energy per unit length of 5400 J/m and a powder feed rate per unit length of 0.25 g/m

Source Discrimination in Adults with Attention Deficit Hyperactivity Disorder

<p>Objectives: The context of memory experiences is referred to as source memory and can be distinguished from the content of episodic item memory. Source memory represents a crucial part of biographic events and elaborate memory experiences. Whereas individuals with attention deficit hyperactivity disorder (ADHD) were shown to have inefficient item memory, little is known about the context of memory experiences.</p><p>Methods: The present study compared 37 adult patients with a diagnosed ADHD with 40 matched healthy participants on a word list paradigm. Memory functions of encoding, retention and source discrimination were assessed. Furthermore, standardized measures of memory and executive control were applied in order to explore a qualitative differentiation of memory components.</p><p>Results: Adult patients with ADHD showed impaired performance in encoding of new information whereas the retention of encoded items was found to be preserved. The most pronounced impairment of patients with ADHD was observed in source discrimination. Regression models of cognitive functions on memory components supported some qualitative differentiation.</p><p>Conclusions: Data analysis suggests a differential pattern of memory impairment in adults suffering from ADHD with a particular deficit in source discrimination. Inefficient source discrimination in adults with ADHD can affect daily functioning by limiting biographic awareness and disturbing general cognitive processes.</p>

Autopercepção da saúde bucal e impacto na qualidade de vida do idoso: uma abordagem quanti-qualitativa Self-perception of oral health and impact on quality of life among the elderly: a quantitative-qualitative approach

Este estudo, de abordagem quanti-qualitativa, objetivou aprofundar o entendimento das relações entre autopercepção, impacto na qualidade de vida e condições bucais de idosos. Exame clínico e entrevista gravada contendo questões objetivas e discursivas foram realizados com 45 idosos. Conduziu-se análise descritiva quantitativa das questões objetivas e referentes ao exame clínico e à análise de conteúdo das questões discursivas de abordagem qualitativa. Imagens fotográficas do estado bucal foram relacionadas a trechos das entrevistas. A análise quantitativa evidenciou: 4,8 dentes em média; CPOD (número de dentes cariados, perdidos e obturados) médio de 29,9; 57,7% eram desdentados, 60% acreditavam não necessitar tratamento, 75% sofriam impacto na qualidade de vida devido às condições bucais, apesar de 67% perceberem positivamente sua saúde bucal. Na análise qualitativa constatou-se subestimação de sintomas, falta de esperança e resignação frente às limitações impostas pelo precário estado clínico. Muitos encararam as limitações como conseqüência do envelhecimento e não como problema que mereça ser corrigido. O que mais incomodou foram as relações de dependência e a proximidade com a morte, minimizando outros problemas. A população idosa foi informada de que poderia modificar sua autopercepção, conscientizando-a que esta realidade pode ser modificada.<br>A qualitative-quantitative approach was used in this study to obtain a clearer understanding of the relationship between self-perception, impact on quality of life and oral health among the elderly. Clinical examination and recorded interviews with objective and discursive questions were conducted with 45 institutionalized elderly people. Descriptive analyses of quantitative data were made. The interviews were transcribed and a systematic reading of the interviews was carried out selecting the components related to the categories under analysis. Photographic images of the oral clinical status were correlated with participants' speech. Quantitative analysis revealed: an average of 4.8 teeth; DMFT were 29.9; 57.7 % were toothless; 60% believed they did not need dental care; 75% suffered a great impact on quality of life due to oral health conditions, despite the fact that 67% evaluated their oral health positively. Underestimation of symptoms, lack of hope and resignation due to limitations regarding poor clinical status were detected. Most elderly people viewed such limitations as a consequence of aging and not as a problem that may be solved. This reality can be changed through information and guidance for elderly people