Algorithm-oriented design of efficient many-core architectures applied to dense matrix multiplication

Recent integrated circuit technologies have opened the possibility to design parallel architectures with hundreds of cores on a single chip. The design space of these parallel architectures is huge with many architectural options. Exploring the design space gets even more difficult if, beyond performance and area, we also consider extra metrics like performance and area efficiency, where the designer tries to design the architecture with the best performance per chip area and the best sustainable performance. In this paper we present an algorithm-oriented approach to design a many-core architecture. Instead of doing the design space exploration of the many core architecture based on the experimental execution results of a particular benchmark of algorithms, our approach is to make a formal analysis of the algorithms considering the main architectural aspects and to determine how each particular architectural aspect is related to the performance of the architecture when running an algorithm or set of algorithms. The architectural aspects considered include the number of cores, the local memory available in each core, the communication bandwidth between the many-core architecture and the external memory and the memory hierarchy. To exemplify the approach we did a theoretical analysis of a dense matrix multiplication algorithm and determined an equation that relates the number of execution cycles with the architectural parameters. Based on this equation a many-core architecture has been designed. The results obtained indicate that a 100 mm(2) integrated circuit design of the proposed architecture, using a 65 nm technology, is able to achieve 464 GFLOPs (double precision floating-point) for a memory bandwidth of 16 GB/s. This corresponds to a performance efficiency of 71 %. Considering a 45 nm technology, a 100 mm(2) chip attains 833 GFLOPs which corresponds to 84 % of peak performance These figures are better than those obtained by previous many-core architectures, except for the area efficiency which is limited by the lower memory bandwidth considered. The results achieved are also better than those of previous state-of-the-art many-cores architectures designed specifically to achieve high performance for matrix multiplication.

GPU implementation of a hyperspectral coded aperture algorithm for compressive sensing

This paper presents a new parallel implementation of a previously hyperspectral coded aperture (HYCA) algorithm for compressive sensing on graphics processing units (GPUs). HYCA method combines the ideas of spectral unmixing and compressive sensing exploiting the high spatial correlation that can be observed in the data and the generally low number of endmembers needed in order to explain the data. The proposed implementation exploits the GPU architecture at low level, thus taking full advantage of the computational power of GPUs using shared memory and coalesced accesses to memory. The proposed algorithm is evaluated not only in terms of reconstruction error but also in terms of computational performance using two different GPU architectures by NVIDIA: GeForce GTX 590 and GeForce GTX TITAN. Experimental results using real data reveals signficant speedups up with regards to serial implementation.

GPU implementation of the simplex identification via split augmented Lagrangian

Hyperspectral imaging can be used for object detection and for discriminating between different objects based on their spectral characteristics. One of the main problems of hyperspectral data analysis is the presence of mixed pixels, due to the low spatial resolution of such images. This means that several spectrally pure signatures (endmembers) are combined into the same mixed pixel. Linear spectral unmixing follows an unsupervised approach which aims at inferring pure spectral signatures and their material fractions at each pixel of the scene. The huge data volumes acquired by such sensors put stringent requirements on processing and unmixing methods. This paper proposes an efficient implementation of a unsupervised linear unmixing method on GPUs using CUDA. The method finds the smallest simplex by solving a sequence of nonsmooth convex subproblems using variable splitting to obtain a constraint formulation, and then applying an augmented Lagrangian technique. The parallel implementation of SISAL presented in this work exploits the GPU architecture at low level, using shared memory and coalesced accesses to memory. The results herein presented indicate that the GPU implementation can significantly accelerate the method's execution over big datasets while maintaining the methods accuracy.

Parallel GPU architecture for hyperspectral unmixing based on augmented Lagrangian method

Hyperspectral imaging has become one of the main topics in remote sensing applications, which comprise hundreds of spectral bands at different (almost contiguous) wavelength channels over the same area generating large data volumes comprising several GBs per flight. This high spectral resolution can be used for object detection and for discriminate between different objects based on their spectral characteristics. One of the main problems involved in hyperspectral analysis is the presence of mixed pixels, which arise when the spacial resolution of the sensor is not able to separate spectrally distinct materials. Spectral unmixing is one of the most important task for hyperspectral data exploitation. However, the unmixing algorithms can be computationally very expensive, and even high power consuming, which compromises the use in applications under on-board constraints. In recent years, graphics processing units (GPUs) have evolved into highly parallel and programmable systems. Specifically, several hyperspectral imaging algorithms have shown to be able to benefit from this hardware taking advantage of the extremely high floating-point processing performance, compact size, huge memory bandwidth, and relatively low cost of these units, which make them appealing for onboard data processing. In this paper, we propose a parallel implementation of an augmented Lagragian based method for unsupervised hyperspectral linear unmixing on GPUs using CUDA. The method called simplex identification via split augmented Lagrangian (SISAL) aims to identify the endmembers of a scene, i.e., is able to unmix hyperspectral data sets in which the pure pixel assumption is violated. The efficient implementation of SISAL method presented in this work exploits the GPU architecture at low level, using shared memory and coalesced accesses to memory.

Parallel hyperspectral unmixing method via split augmented lagrangian on GPU

One of the main problems of hyperspectral data analysis is the presence of mixed pixels due to the low spatial resolution of such images. Linear spectral unmixing aims at inferring pure spectral signatures and their fractions at each pixel of the scene. The huge data volumes acquired by hyperspectral sensors put stringent requirements on processing and unmixing methods. This letter proposes an efficient implementation of the method called simplex identification via split augmented Lagrangian (SISAL) which exploits the graphics processing unit (GPU) architecture at low level using Compute Unified Device Architecture. SISAL aims to identify the endmembers of a scene, i.e., is able to unmix hyperspectral data sets in which the pure pixel assumption is violated. The proposed implementation is performed in a pixel-by-pixel fashion using coalesced accesses to memory and exploiting shared memory to store temporary data. Furthermore, the kernels have been optimized to minimize the threads divergence, therefore achieving high GPU occupancy. The experimental results obtained for the simulated and real hyperspectral data sets reveal speedups up to 49 times, which demonstrates that the GPU implementation can significantly accelerate the method's execution over big data sets while maintaining the methods accuracy.

Descending pain modulation in a Kaolin-induced hydrocephalus rat model

Pain transmission at the spinal cord is modulated by descending actions that arise from supraspinal areas which collectively form the endogenous pain control system. Two key areas involved of the endogenous pain control system have a circunventricular location, namely the periaqueductal grey (PAG) and the locus coeruleus (LC). The PAG plays a crucial role in descending pain modulation as it conveys the input from higher brain centers to the spinal cord. As to the LC, it is involved in descending pain inhibition by direct noradrenergic projections to the spinal cord. In the context of neurological defects, several diseases may affect the structure and function of the brain. Hydrocephalus is a congenital or acquired disease characterized by an enlargement of the ventricles which leads to a distortion of the adjacent tissues, including the PAG and LC. Usually, patients suffering from hydrocephalus present dysfunctions in learning and memory and also motor deficits. It remains to be evaluated if lesions of the periventricular brain areas involved in pain control during hydrocephalus may affect descending pain control and, herein, affect pain responses. The studies included in the present thesis used an experimental model of hydrocephalus (the rat injected in the cisterna magna with kaolin) to study descending modulation of pain, focusing on the two circumventricular regions referred above (the PAG and the LC). In order to evaluate the effects of kaolin injection into the cisterna magna, we measured the degree of ventricular dilatation in sections encompassing the PAG by standard cytoarquitectonic stanings (thionin staining). For the LC, immunodetection of the noradrenaline-synthetizing enzyme tyrosine hydroxylase (TH) was performed, due to the noradrenergic nature of the LC neurons. In general, rats with kaolin-induced hydrocephalus presented a higher dilatation of the 4th ventricle, along with a tendency to a higher area of the PAG. Due to the validated role of detection the c-fos protooncogene as a marker of neuronal activation, we also studied neuronal activation in the several subnuclei which compose the PAG, namely the dorsomedial, dorsolateral, lateral and ventrolateral (VLPAG) parts. A decrease in the numbers of neurons immunoreactive for Fos protein (the product of activation of the c-fos protooncogene) was detected in rats injected with kaolin, whereas the remaining PAG subnuclei did not present changes in Fos-immunoreactive nuclei. Increases in the levels of TH in the LC, namely at the rostral parts of the nucleus, were detected in hydrocephalic animals. The following pain-related parameters were measured, namely 1) pain behavioural responses in a validated pain inflammatory test (the formalin test) and 2) the nociceptive activation of spinal cord neurons. A decrease in behavioral responses was detected in rats with kaolin-induced hydrocephalus was detected, namely in the second phase of the test (inflammatory phase). This is the phase of the formalin test in which the motor behaviour is less important, which is important since a semi-quantitative analysis of the motor performance of rats injected with kaolin indicates that these animals may present some motor impairments. Collectively, the results of the behavioral studies indicate that rats with kaolin-induced hydrocephalus exhibit hypoalgesia. A decrease in Fos expression was detected at the superficial dorsal layers of the spinal cord in rats with kaolin-induced hydrocephalus, further indicating that hydrocephalus decreases nociceptive responses. It remains to be ascertained if this is due to alterations in the PAG and LC in the rats with kaolin-induced hydrocephalus, which may affect descending pain modulation. It remains to be evaluated what are the mechanisms underlying the increased pain inhibition at the spinal dorsal horn in the hydrocephalus rats. Regarding the VLPAG, the decrease in neuronal activity may impair descending modulation. Since the LC has higher levels of TH in rats with kaolininduced hydrocephalus, which also appears to increase the noradrenergic innervation in the spinal dorsal horn, it is possible that an increase in the release of noradrenaline at the spinal cord accounts for pain inhibition. Our studies also determine the need to study in detail patients with hydrocephalus namely in what concerns their thresholds to pain and to perform imaging studies focused on the structure and function of pain control areas in the brain.

Condition-Based Diagnosis of Mechatronic Systems Using a Fractional Calculus Approach

While fractional calculus (FC) is as old as integer calculus, its application has been mainly restricted to mathematics. However, many real systems are better described using FC equations than with integer models. FC is a suitable tool for describing systems characterised by their fractal nature, long-term memory and chaotic behaviour. It is a promising methodology for failure analysis and modelling, since the behaviour of a failing system depends on factors that increase the model’s complexity. This paper explores the proficiency of FC in modelling complex behaviour by tuning only a few parameters. This work proposes a novel two-step strategy for diagnosis, first modelling common failure conditions and, second, by comparing these models with real machine signals and using the difference to feed a computational classifier. Our proposal is validated using an electrical motor coupled with a mechanical gear reducer.

Detrimental role of prolonged sleep deprivation on adult neurogenesis

Adult mammalian brains continuously generate new neurons, a phenomenon called adult neurogenesis. Both environmental stimuli and endogenous factors are important regulators of adult neurogenesis. Sleep has an important role in normal brain physiology and its disturbance causes very stressful conditions, which disrupt normal brain physiology. Recently, an influence of sleep in adult neurogenesis has been established, mainly based on sleep deprivation studies. This review provides an overview on how rhythms and sleep cycles regulate hippocampal and subventricular zone neurogenesis, discussing some potential underlying mechanisms. In addition, our review highlights some interacting points between sleep and adult neurogenesis in brain function, such as learning, memory, and mood states, and provides some insights on the effects of antidepressants and hypnotic drugs on adult neurogenesis.

Fractional State Space Analysis of Temperature Time Series

Atmospheric temperatures characterize Earth as a slow dynamics spatiotemporal system, revealing long-memory and complex behavior. Temperature time series of 54 worldwide geographic locations are considered as representative of the Earth weather dynamics. These data are then interpreted as the time evolution of a set of state space variables describing a complex system. The data are analyzed by means of multidimensional scaling (MDS), and the fractional state space portrait (fSSP). A centennial perspective covering the period from 1910 to 2012 allows MDS to identify similarities among different Earth’s locations. The multivariate mutual information is proposed to determine the “optimal” order of the time derivative for the fSSP representation. The fSSP emerges as a valuable alternative for visualizing system dynamics.

O Papel da Memória de Trabalho na Perturbação do Desenvolvimento da Coordenação, em Crianças Com Diagnóstico de Perturbação de Hiperatividade e Défice de Atenção

Este estudo pretende (1) encontrar a prevalência da Perturbação do Desenvolvimento da Coordenação (PDC) em crianças com Perturbação de Hiperatividades e Défice de Atenção (PHDA); (2) analisar qual a prevalência de défices de memória de trabalho verbal e não-verbal, em crianças com PHDA e comparar o desempenho entre as crianças que só apresentam PHDA e aquelas que apresentam também PDC; (3) verificar se a ocorrência de PDC é agravada, de acordo com a presença ou ausência de alterações de memória de trabalho e se estas podem ser consideradas fatores de risco ou de proteção para a manifestação de PDC, enquanto comorbilidade de PHDA. Foram selecionadas 37 crianças com diagnóstico de PHDA, com idades compreendidas entre os 7 e os 14 anos. A componente motora foi avaliado com a versão curta do Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) e o Questionário de Perturbação do Desenvolvimento da Coordenação 2007 (DCDQ’07); a memória de trabalho foi avaliada através da Figura Complexa de Rey, Trail Making Test - parte B e Memória de Dígitos – sentido inverso. Para determinar o impacto da memória de trabalho na componente motora, recorreu-se a uma regressão logística. Encontrou-se uma prevalência de PDC de 51% e de défices ao nível da memória de trabalho verbal e não-verbal de 60% e 80%, respetivamente, para a amostra total de crianças com PHDA. A terapêutica farmacológica para a PHDA revelou-se fator protetor para a manifestação de PDC, principalmente quando a primeira se encontra associada com o nascimento de termo. Um mau desempenho no teste Memória de Dígitos – sentido inverso é fator de risco para a manifestação de PDC, em crianças com PHDA. Este estudo permitiu verificar que crianças com PHDA+PDC apresentam défices motores genuínos, característicos de manifestação de PDC. Parecem também existir relações bastante complexas entre a memória de trabalho e os mecanismos de controlo motor na PHDA, sendo que estes podem ser distintos quando está presente uma comorbilidade de PDC.

Data-centric concurrency control on the java programming language

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Avaliação clínica na disfunção fronto-estriatal : movimento e cognição

RESUMO: Os circuitos fronto-estriatais constituem um sistema em ansa fechada que une diversas regiões do lobo frontal aos gânglios da base, participando, com outras áreas cerebrais, no controlo do movimento, cognição e comportamento. As Distonias Primárias, a Doença de Parkinson e a Hidrocefalia de Pressão Normal, são doenças do movimento caracterizadas por disfunção do circuito fronto-estriatal motor. A conectividade funcional entre as diversas ansas do sistema fronto-estriatal, permite prever que as doenças do movimento possam também acompanhar-se de sintomas da esfera cognitiva e comportamental, cuja avaliação seria importante no manejo diagnóstico e terapêutico dos doentes. Objectivos Os nossos objectivos foram avaliar, por estudos clínicos, a relação entre sintomas motores, cognitivos e comportamentais em três doenças do movimento com fisiopatologias diversas - distonias Primárias, Doença de Parkinson e Hidrocefalia de Pressão Normal - analisando os dados sob a perspectiva teórica fornecida pelo conhecimentos dos vários circuitos frontoestriatais. Os nossos objectivos específicos para cada doença foram: a) Distonias Primárias: avaliação de disfunção executiva em doentes com Distonia Primária e relação com a gravidade dos sintomas motores b) Doença de Parkinson: 1. avaliação breve das funções mentais nas fases iniciais da doença, incluindo análise longitudinal para determinação de factores preditivos para declínio cognitivo; 2. relação entre a função motora e cognitiva e a Perturbação do Comportamento do sono REM, incluindo análise longitudinal; 3.avaliação de sintomas psiquiátricos, de um ponto de vista global e especificamente com incidência sobre as Perturbações do Controlo do Impulso (PCI). c) Hidrocefalia de Pressão Normal: 1. caracterização das alterações da marcha, incluindo comparação com a Doença de Parkinson; 2. caracterização das alterações cognitivas e da relação entre estas e a disfunção da marcha; 3. estudo evolutivo das alterações da marcha e cognitiva em doentes submetido a cirurgia e doentes não submetidos a cirurgia. Métodos: A Distonia Primária, a Doença de Parkinson e a Hidrocefalia de Pressão Normal foram diagnosticadas segundo critérios clínicos validados. Sempre que justificado, foram recrutados grupos de controlo, com indivíduos sem doença, emparelhados para idade, sexo e grau de escolaridade. Os doentes foram avaliados com instrumentos de aplicação clinica directa, incluindo escalas de função motora, testes neuropsicológicos globais e dirigidos às funções executivas e escalas de avaliação psiquiátrica. Testes aplicados nas Distonias Primárias: Unified Dystonia Rating Scale, Wisconsin Card Sorting Test, teste de Stroop, teste de cubos da WAIS, Teste de Retenção Visual de Benton; na Doença de Parkinson: Unified Parkinson's Disease Rating Scale, Frontal Assessment Battery (FAB), Mini-Mental State Examination (MMSE), REM-sleep behaviour disorder Questionnaire; Symptom Chek-list 90-R, Brief Psychiatric Rating Scale, FAS (fluência verbal lexical) Nomeação de Animais (Fluência verbal semântica), prova de repetição de dígitos (WAIS), Rey auditory verbal learning test, teste de Stroop, matrizes progressivas de Raven, Questionnaire for Impulsive-Compulsive Disorders; na HPN: prova cronometrada de marcha,MMSE, prova de memória imediata da WAIS, prova de repetição de dígitos (WAIS), FAB, desenho complexo de Rey, teste de Stroop, cancelamento de letras, teste Grooved Pegboard. Os doentes com HPN foram também submetidos a estudo imagiológico. A avaliação estatística foi adaptada às características de cada um dos estudos.Resultados Distonias Primárias: encontrámos défices de função executiva, envolvendo dificuldade na mudança entre sets cognitivos, bem como correlação significativa entre as pontuações nos testes cronometrados e a gravidade dos sintomas motores. Doença de Parkinson: os doentes com DP obtiveram pontuações significativamente inferiores na FAB e em sub-testes do MMSE (memória e função visuo-espacial). A pontuação no MMSE encontrava-se significativamente correlacionada com itens da função motora não relacionados com o tremor. A disfunção da marcha, a disartria, o fenótipo não tremorígeno, a presença de alucinações e pontuação abaixo do ponto de corte na MMSE, foram factores preditivos de demência na avaliação longitudinal. A rigidez e a disartria foram factores preditivos de declínio nas funções frontais. A disfunção frontal foi factor preditivo de declínio na pontuação do MMSE. Encontrámos uma prevalência elevada de RBD nas fases iniciais da DP, que o estudo longitudinal mostrou ser factor preditivo de declínio motor, nomeadamente por agravamento da bradicinésia. Encontrámos também uma prevalência elevada de sintomas psiquiátricos, nomeadamente psicose, depressão, ansiedade, somatização e sintomas obsessivo-compulsivos. As PCI não se encontravam relacionadas com o fenótipo motor, com as complicações motoras do tratamento dopaminérgico ou com a disfunção cognitiva. HPN: os doentes com HPN e os DP apresentaram um padrão disfunção da marcha semelhante, caraterizado por passos curtos, lentidão e dificuldades de equilíbrio, sendo os sintomas mais graves na HPN. Os doentes de Parkinson com maior duração de doença, maior dose de dopaminérgicos e fenótipo motor acinético-rígido apresentaram um padrão de disfunção da marcha de gravidade semelhante ao encontrado na HPN. As alterações vasculares da substância branca, em particular as encontradas na região frontal, encontravam-se negativamente correlacionadas com a melhoria da marcha após PL. O estudo das funções cognitivas mostrou um padrão de atingimento global, com valores mais baixos na cópia do desenho complexo de Rey. Os resultados nas provas de função cognitiva não se encontravam significativamente correlacionados com os resultados na prova da marcha. A progressão na disfunção da marcha encontrava-se relacionada com o tratamento não cirúrgico, idade superior na primeira avaliação, presença de lesões da substância branca, e presença de factores de risco vascular, ao passo que não foram encontrados factores que predissessem de modo significativo o agravamento da função cognitiva. Conclusões: Os resultados dos diversos estudos, evidenciam a presença de alterações cognitivas e comportamentais nas três doenças de movimento. O padrão destas alterações e o modo como estas se relacionaram com os sintomas motores variou de doença para doença. Nas Distonias primárias, a perseveração cognitiva poderá ser o sintoma correspondente à perseveração motora própria da doença, sugerindo disfunção no circuito dorso-lateral frontoestriatal. A correlação entre a gravidade motora da doença e o resultado nos testes cognitivos cronometrados, poderá ser o efeito da relação entre bradicinésia e bradifrenia. Na Doença de Parkinson, o espectro de alterações é mais acentuado, espelhando a disseminação do processo degenerativo no SNC. Para além dos sintomas de disfunção executiva, sugerindo disfunção das tês ansas não motoras, existem sinais de disfunção cognitiva global, estas com uma influência mais significativa no desenvolvimento da demência. A relação entre os diferentes sintomas motores e cognitivos é também complexa, embora se evidencie uma dissociação significativa entre o tremor, sem relação com os sintomas não motores, e os sintomas motores não tremorígenos, relacionados com o declínio cognitivo. Enquanto que a presença de RBD parece ser um factor preditivo de agravamento motor, os sintomas psiquiátricos, também muito frequentes, apresentam uma relação menos clara com a função motora. Destes, os sintomas obsessivo-compulsivos são aqueles que com mais frequência se atribuem a disfunção do sistema fronto-estriatal, nomeadamente da ansa orbito-frontal. As PCI também não mostraram ter relação com os sintomas motores ou cognitivos. Na HPN, é patente o carácter fronto-estriatal das alterações da marcha, demonstrado tanto na sua caracterização quanto no efeito deletério das lesões vasculares da substância branca do lobo frontal na recuperação da marcha após PL. As alterações cognitivas parecem ter um padrão mais difuso, o que talvez explique a falta de correlação com os sintomas motores - esta dissociação pode ser causada quer por diferença nos mecanismos fisiopatológicos quer por presença de comorbilidades cognitivas. --------- ABSTRACT: Fronto-striatal circuits constitute a closed loop system which connects different parts of the frontal lobes to the basal ganglia. They are engaged in motor, cognitive and behavioural control. Primary Dystonia, Parkinson's Disease and Normal-Pressure Hydrocephalus are movement disorders caused by disturbance of the motor fronto-striatal circuit. The existence of cognitive and behavioural dysfunction in these movement disorders is predictable, given the functional connectivity between the several distinct loops of the circuit. Evaluation of cognitive and behavioural dysfunction in these three disorders is thus both of clinical and theoretical relevance. Objectives Our objectives were to evaluate, by clinical means, the relation between motor, cognitive and behavioural symptoms in three movement disorders with different pathophysiological backgrounds - Primary Dystonia, Parkinson's Disease and Normal-Pressure Hydrocephalus - and to analyse the study results under the theoretical framework formed by present knowledge of the fronto-estriatal system. Specific objectives: a) Primary Dystonia: executive dysfunction assessment and correlation analysis with motor dysfunction severity; b) Parkinson's Disease: 1. brief cognitive assessment in the early stages of disease, including a longitudinal analysis for determination of predictive factors for cognitive decline; 2. to investigate the relation between RBD and cognitive and motor dysfunction, including a longitudinal analysis; 3. psychiatric symptom assessment, with particular incidence on Impulse Control Disorders; c) Normal-Pressure Hydrocephalus: 1. gait dysfunction characterization and comparison with Parkinson's Disease patients; 2. determination of cognitive dysfunction profile and its relation with gait dysfunction; 3. follow-up study of cognitive and motor outcome in patients submitted and not submitted to shunt surgery. Methods: Primary Dystonia, Parkinson's Disease and Normal Pressure Hydrocephalus were diagnosed according to clinically validate criteria. Where warranted, we recruited control groups formed by healthy individuals, matched for age, sex and educational level. Patients were evaluated with instruments of direct clinical application, including motor function scales, neuropsychological tests aimed at global and executive functions and psychiatric rating scales. Tests used in Primary Dystonia: Unified Dystonia Rating Scale, Wisconsin Card Sorting Test, Stroop Test, Cube Assembly test (WAIS), Benton’s Visual Retention Test; in Parkinson's Disease: Unified Parkinson's Disease Rating Scale, Frontal Assessment Battery (FAB) , Mini-mental State Examination (MMSE), REM-sleep behavior disorder Questionnaire, Symptom Check-list 90- R, Brief Psychiatric Rating Scale, FAS (phonetic verbal fluency), semantic verbal fluency test, digit span test (WAIS), auditory verbal learning test,Stroop test, Raven's progressive Matrices, Questionnaire for Impulsive-Compulsive Disorders; in NPH: timed walking test, MMSE, immediate memory task (WAIS), digit span test (WAIS), FAB, Rey’s Complex Figure test, Stroop test, letter cancellation test, Perdue Pegboard test. NPH patients were also subjected to an imaging study. Statistics were adapted to the characteristics of each study.Results: Primary Dystonia: we found set-shifting deficits as well as significant correlation between timed neuropsychological tests and dystonia severity. Parkinson's Disease: PD patients had significantly lower scores on the FAB and on the memory and visuo-spatial tests of the MMSE; MMSE scores were significantly correlated to non-tremor motor scores; gait dysfunction and speech scores, non-tremor motor phenotype, hallucinations and scores bellow cut-off on the MMSE were predictive of dementia at follow-up; speech and rigidity scores were predictive of frontal type decline; frontal dysfunction was predictivy of decline in MMSE scores; RBD bradykinesia worsening; psychiatric symptoms were prevalent, particularly Psychosis, Depression, Anxiety, Somatisation and Obsessive-Compulsive Symptoms; Impulse Control Disorders were unrelated to motor phenotype,motor side effects of dopamine treatment and executive function; NPH: gait dysfunction was worse in NPH when compared to PD patients, although the pattern was similarly characterized by slowness, short steps and disequilibrium; PD patients whose gait disturbance was as severe as that of NPH patients were characterized by longer disease duration, predominance of non-tremor motor scores, more advanced disease stage and higher dopamine dose; frontal white matter lesions correlated negatively with improvement after LP; cognitive function assessment revealed wide spread deficits, with lower results on the drawing of the complex figure of Rey, which were not significantly correlated to gait dysfunction; older age, white matter lesions and the presence of vascular risk factors were predictive factors for motor but not cognitive function worsening. Conclusion: Results from our studies highlight the presence of cognitive and behavioural dysfunction in all three movement disorders. Symptom pattern and the relation with ovement derangement varied according to the disease. In Primary Dystonia, set-shifting difficulties could be the cognitive counterpart of motor perseveration characteristic of this disorder, suggesting dysfunction of the dorso-lateral circuit. The relation between timed tests and dystonia severity could suggest a relation between bradyphrenia and bradykinesia in Primary Dystonia. In Parkinson's Disease patients, the spectrum of non-motor symptoms is wider, probably reflecting the spread of neurodegeneration beyond the fronto-striatal circuits. While frontal type deficits predominate, suggestive of dorso-lateral and orbito-frontal dysfunction, non-frontal deficits were also apparent in the initial stages of disease, and were predictive of dementia at follow-up. The relationship between cognitive and motor symptoms is complex, although the results strongly suggest a dissociation between tremor symptoms, which bore no relation with non-motor symptoms, and non-tremor symptoms,whichwas frequent, and a predictive factor for which were related with cognitive decline. While RBD was found to be a predictive factor for bradykinesia worsening, psychiatric symptoms, which were also frequent, showed no apparent relation with motor dysfunction. Relevant to our theoretical consideration was the high prevalence of OCS, which have been attributed to orbito-frontal dysfunction. As to the particular case of ICD, we found no relation either with motor or cognitive dysfunction. The fronto-striatal nature of gait dysfunction in NPH is suggest by the clinical characterization study and by the effects of frontal white matter lesions on gait recovery after LP, whereas cognitive dysfunction presented a more diffuse pattern, which could explain the lack or relation with gait assessment results and also the different outcome on the longitudinal study - this dissociation could be caused by a real difference in pathophysiological mechanisms or, in alternative, be due to the existence of cognitive comorbidities.

Haptic robot-environment interaction for self-supervised learning in ground mobility

Dissertação para obtenção do Grau de Mestre em Engenharia Eletrotécnica e de Computadores

Necessidades de cuidados no idoso: comparação entre um Centro de Dia e um serviço de apoio domiciliário

RESUMO: Promover a qualidade de vida no envelhecimento implica responder às necessidades de cuidados dos mais velhos. Actualmente, muitos idosos permanecem no seu domicílio, o que exige a prestação adequada de cuidados informais e/ou formais nesse contexto. O presente estudo teve como objectivo identificar e comparar as necessidades de cuidados de utentes de um centro de dia e de um serviço de apoio domiciliário numa Instituição Particular de Solidariedade Social. A amostra foi constituída por 54 utentes idosos e pelos seus cuidadores informais. Os utentes foram avaliados com recurso a: Camberwell Assessment of Need for the Elderly, Geriatric Depression Scale, Mini Mental State Examination, Índice de Barthel e Escala de Lawton e Brody para as actividades de vida diária. Os respectivos cuidadores informais foram avaliados quanto a necessidades de cuidados e a sobrecarga familiar. As necessidades de cuidados mais frequentes na amostra estavam relacionadas com alimentação, companhia, saúde física e actividades diárias. Parte das necessidades estavam cobertas. Porém, muitas necessidades psicológicas e sociais, nomeadamente actividades diárias, companhia e memória, não estavam cobertas, em particular nos utentes de apoio domiciliário. Tal como esperado, foi encontrado um maior número de necessidades de cuidados em situações de dependência e de doenças neuropsiquiátricas. Comparativamente com os utentes de centro de dia, os utentes de apoio domiciliário apresentaram números superiores de necessidades de cuidados, necessidades não cobertas. Uma melhor identificação das necessidades de cuidados e dos factores associados a estas poderá ajudar a delinear intervenções adequadas em centros de dia e em serviços de apoio domiciliário.------------ABSTRACT: To promote quality of life in aging means responding to the health and social needs of older people. Today, elderly people tend to stay at home until later stages of disease, which requires the provision of adequate informal care, formal care or both. This study aimed to identify and compare the needs for care of users of a day centre and a domiciliary care service, in a nonprofit organization in Portugal. The sample consisted of 54 elderly users and of their informal caregivers. The users were assessed using the Camberwell Assessment of Need for the Elderly (CANE), the Geriatric Depression Scale, the Mini Mental State Examination, the Barthel Index and the Lawton and Brody Scale for activities of daily living. Informal caregivers were assessed using the CANE and the Zarit Burden Interview. The more frequent care needs were related to food, company, physical health and daytime activities. A proportion of needs were met. However, many psychological and social needs were unmet, namely daytime activities, company and memory, and this was so in particular concerning domiciliary care users.As expected, a higher number of needs was related to dependency and the presence of neuropsychiatric conditions. The domiciliary care users had more total needs and more unmet needs when compared with day centre users. The identification of needs for care and their associated factors can help in the planning of appropriate interventions in day centres and domiciliary care services.

Adaptation as a part of system resilience. insights from fish producers organizations in Portugal

Complex problems of globalized society challenge its adaptive capacity. However, it is precisely the nature of these human induced problems that provide enough evidence to show that adaptability may not be on a resilient path. This thesis explores the ambiguity of the idea of adaptation (and its practice) and illustrates the ways in which adaptability contributes to resilience of social ecological systems. The thesis combines a case study and grounded theory approach and develops an analytical framework to study adaptability in resource users’ organizations: from what it depends on and what the key challenges are for resource management and system resilience. It does so for the specific case of fish producers’ organizations (POs) in Portugal. The findings suggest that while ecological and market context, including the type of crisis, may influence the character of fishers’ adaptation within POs (i.e. anticipatory, maladaptive and reactively adaptive), it does not determine it. Instead, it makes agency even more crucial (i.e. leadership, trust and agent’s perceptions in terms of their impact on fishers’ motivation to learn from each other). In sum, it was found that internal adaptation can improve POs’ contribution to fishery management and resilience, but it is not a panacea and may, in some cases, increase system vulnerability to change. Continuous maladaptation of some Portuguese POs points at a basic institutional problem (fish market regime), which clearly reduces fisheries resilience as it promotes overfishing. However, structural change may not be sufficient to address other barriers to Portuguese fishers’ (PO members) adaptability, such as history (collective memory) and associated problematic self-perceptions. The agency (people involved in structures and practices) also needs to change. What and how institutional change and agency change build on one another (e.g. comparison of fisheries governance in Portugal and other EU countries) is a topic to be explored in further research.