SCRIPTORIUM (Université de Moncton)
Not a member yet
2550 research outputs found
Sort by
A Novel Framework for Classification of Different Alzheimer's Disease Stages Using CNN Model
No full textBackground: Alzheimer’s, the predominant formof dementia, is a neurodegenerative brain disorder with no known cure. With the lack of innovative findings to diagnose and treat Alzheimer’s, the number of middle-aged people with dementia is estimated to hike nearly to 13 million by the end of 2050. The estimated cost of Alzheimer’s and other related ailments is USD321 billion in 2022 and can rise above USD1 trillion by the end of 2050. Therefore, the early prediction of such diseases using computer-aided systems is a topic of considerable interest and substantial study among scholars. The major objective is to develop a comprehensive framework for the earliest onset and categorization of different phases of Alzheimer’s. Methods: Experimental work of this novel approach is performed by implementing neural networks (CNN) on MRI image datasets. Five classes of Alzheimer’s disease subjects are multi-classified. We used the transfer learning determinant to reap the benefits of pre-trained health data classification models such as the MobileNet. Results: For the evaluation and comparison of the proposed model, various performance metrics are used. The test results reveal that the CNN architectures method has the following characteristics: appropriate simple structures that mitigate computational burden, memory usage, and overfitting, as well as offering maintainable time. The MobileNet pre-trained model has been fine-tuned and has achieved 96.6 percent accuracy for multi-class AD stage classifications. Other models, such as VGG16 and ResNet50 models, are applied tothe same dataset whileconducting this research, and it is revealed that this model yields better results than other models. Conclusion: The study develops a novel framework for the identification of different AD stages. The main advantage of this novel approach is the creation of lightweight neural networks. MobileNet model is mostly used for mobile applications and was rarely used for medical image analysis; hence, we implemented this model for disease detection andyieldedbetter results than existing models.udemauteur: Habib Hama
Analyses of Response Time Data in the Same-Different Task
No full textThe Same–Different task presents two stimuli in close succession and participants must indicate whether they are completely identical or if there are any attributes that differ. While the task is simple, its results have proven difficult to explain. Notably, response times are characterized by a fast-same effect whereby Same responses are faster than Different responses even though identical stimuli should be exhaustively processed to be accurate. Herein, we examine a little more than a quarter million response times (N = 255,744) obtained from 327 participants who participated in one of 14 variants of the task involving minor changes in the stimuli or their durations. We performed distribution fitting and analyzed estimated parameters stemming from the ex-Gaussian, lognormal, and Weibull distributions to infer the cognitive processing characteristics underlying this task. The results exclude serial processing of the stimuli and do not support dual-route processing. The fast-same effect appears only through a shift of the entire response time distributions, a feature impossible to detect solely with mean response time analyses. An attentionmodulated process driven by entropy may be the most adequate model of the fast-same effect.udemauteur: Bradley Hardin
English Emotional Voice Conversion Using StarGAN Model
No full textThe StarGANv2-VC model is a many-to-many non-parallel generative adversarial network (GAN) voice conversion (VC) model that has proven effective in style conversion tasks. This study aimed to investigate the scalability and diversity of the model for English emotional voice conversion (EVC) across different speakers and emotions. We carried out many experiments using an Emotional Speech Database (ESD), comprising a single speaker-multi-emotion experiment, a multi-speakers-multi-emotions experiment (gender-dependent), and a multi-speakers-multi-emotions experiment (gender-independent). We also assessed the effect of training set size and compared the performance of the StarGANv2-VC model with a CycleGAN model. Our study found that the StarGANv2-VC model accurately converted the pitch of the voice across all four emotions (neutral, happy, sad, and angry). However, the model's efficiency in converting multi-emotions to multi-speakers was not as high as its efficiency in voice conversion for multi-speakers. Further research is needed in this area. We objectively assessed the quality of the converted speech using Mel-frequency cepstral distortion (MCD) and root-mean-square error (RMSE) for spectrum and prosody, respectively. Additionally, we conducted cross-emotion recognition using a convolutional recurrent neural network (CRNN).udemauteur: Sid Ahmed Selouan
Range-wide whole-genome resequencing of the brown bear reveals drivers of intraspecies divergence
No full textPopulation-genomic studies can shed new light on the effect of past demographic processes on contemporary population structure. We reassessed phylogeographical patterns of a classic model species of postglacial recolonisation, the brown bear (Ursus arctos), using a range-wide resequencing dataset of 128 nuclear genomes. In sharp contrast to the erratic geographical distribution of mtDNA and Y-chromosomal haplotypes, autosomal and X-chromosomal multi-locus datasets indicate that brown bear population structure is largely explained by recent population connectivity. Multispecies coalescent based analyses reveal cases where mtDNA haplotype sharing between distant populations, such as between Iberian and southern Scandinavian bears, likely results from incomplete lineage sorting, not from ancestral population structure (i.e., postglacial recolonisation). However, we also argue, using forward-in-time simulations, that gene flow and recombination can rapidly erase genomic evidence of former population structure (such as an ancestral population in Beringia), while this signal is retained by Y-chromosomal and mtDNA, albeit likely distorted. We further suggest that if gene flow is male-mediated, the information loss proceeds faster in autosomes than in X chromosomes. Our findings emphasise that contemporary autosomal genetic structure may reflect recent population dynamics rather than postglacial recolonisation routes, which could contribute to mtDNA and Y-chromosomal discordances.udemauteur: Nicolas Lecomt
Représentations de la diversité chez des enseignantes d'arts visuels au Nouveau-Brunswick francophone
Get PDFL’inclusion scolaire est « [une] philosophie et [un] ensemble de pratiques pédagogiques qui permettent à chaque élève de se sentir valorisé, confiant et en sécurité de sorte qu’il puisse apprendre avec ses pairs dans un milieu d’apprentissage commun et réaliser son plein potentiel » (Ministère de l’Éducation et du Développement de la petite enfance [MEDPE], 2013, p.2). Malgré l’établissement de diverses lois et politiques prônant l’inclusion de tous (Province du Nouveau-Brunswick, 1986; MEDPE, 2013), la mise en place de pratiques pédagogiques inclusives qui tiennent compte de la diversité s’avère toujours un défi en milieu éducatif néo-brunswickois (Porter et AuCoin, 2012). En fait, un cadre conceptuel conçu au sein du Réseau de recherche et de valorisation de la recherche sur le bien-être et la réussite [RÉVERBÈRE] souligne qui lorsqu’une personne ne croit pas dans l’importance de l’inclusion ou possède une représentation plus normalisante de la diversité, cela devient une barrière qui freine la mise en place de pratiques plus inclusives (Borri-Anadon et al., 2021). Ainsi, la nécessité de mieux comprendre ces barrières personnelles en contexte d’inclusion, et plus particulièrement chez les enseignantes en arts visuels, nous a incités à poser les questions de recherche suivantes : quelles sont les représentations de la diversité chez des enseignantes d’arts visuels dans le contexte scolaire inclusif du Nouveau-Brunswick? En nous appuyant sur une méthode de recherche qualitative/interprétative, nous avons mené des entretiens semi-dirigés avec huit enseignantes d’arts visuels d’écoles secondaires et primaires œuvrant en milieux ruraux et urbains. En optant pour une analyse des données selon une logique inductive modérée ainsi que pour la mise en place de certains critères de rigueur afin d’assurer la validité des données obtenues, nous avons été en mesure d’émettre certains constats au sujet des représentations de la diversité chez les participantes. Ainsi, nous constatons que les enseignantes d’arts visuels semblent avoir une représentation assez restreinte de l’inclusion scolaire et de la diversité lorsque celle-ci est associée au contexte scolaire. En d’autres mots, les participantes semblent associer l’inclusion scolaire à certains élèves qui sont dits à besoins particuliers. De ce fait, cette association restreinte peut devenir une barrière à la prise en compte de la diversité des besoins de tous les élèves. À noter que le féminin est priorisé dans l’entièreté de ce texte étant donné que nous n’avons que des participantes. De plus, nous constatons que la grande majorité des personnes enseignant les arts visuels en milieu scolaire sont des enseignantes. Ainsi ce choix nous permet donc d’alléger les texte en évitant les doublons masculins et féminins
Microwave-Assisted Chemical Ablation (MA-CA): A novel microwave-assisted tissue ablation procedure - preliminary assessment of efficiency
No full textMicrowave (MW) ablation is becoming a routine technology in the interventional radiology field. A new approach combining MW ablation and chemical ablation is developed in this paper. The rationale for the development of this Microwave-Assisted Chemical Ablation (MA-CA) technology was to improve the utility of thermal ablation as a minimally invasive treatment for cancer. The experimental conditions for ex vivo bovine liver samples were: A—100 W (120 s) with no addition of ethanol; B—100 W (30 s), wait (60 s) (no power), and 100 W (90 s) with no addition of ethanol; C—100 W (30 s), wait (60 s), 100 W (30 s), and 100 W (60 s) with the addition of 5 mL ethanol; and D—100 W (30 s), wait (60 s), 100 W (30 s), 0 W (30 s) with the addition of 2.5 mL ethanol, and 100 W (60 s) with the addition of 5 mL ethanol (12,000 Joules Total). The results showed that with the use of ethanol, the ablation zone was enlarged and revealed improved sphericity. This novel combination has greater advantages than either technology individually. The objective is to increase the precision and efficiency of MW ablation and to broaden the range of tissues and pathologies that can be treated using this new approach, and to validate the benefits that arise from combining the advantages of MW and chemical ablation in a relevant setting.udemauteur: Gabriel Cormier; Delphine Fouche
Improved modelling and simulation of once‐through and reverse multi‐stage flash desalination configurations
No full textAn improved model for multistage flash (MSF) structures is developed and used to assess the performance of a novel MSF configuration, termed as MSF reversal (RV-MSF) and consisting of reversing the brine circulation stream. The improved model determines the temperature distribution within the stages using heat balance equations while the simplified one, which is commonly used, is based on pre-specified, constant, and equal temperature distribution throughout the stages. The performance of the RV-MSF is investigated and compared with conventional MSF once-through (OT-MSF) with and without brine mixing using simplified and full models. It is found that the simplified model overestimates the required heat transfer specific area for both MSF configurations. Moreover, it underestimates the cooling water and energy requirements for the reversal configuration. Hence, the simplified model may be good for quick analysis but leads to inaccurate design specifications and economic analysis. When brine mixing is utilized, the simplified model still provides erroneous estimates of the heat transfer area for both MSF configurations. Nevertheless, for OT-MSF structure, the simple model can provide comparable predictions with that of the improved model in terms of recovery ratio, performance ratio, and specific energy consumption. For the RV-MSF structure, a mismatch in the two model predictions of surface area, cooling water, and energy requirements is observed. Furthermore, the temperature drop in the cooling system for RV-MSF has a significant influence on the specific surface area and cooling water requirements especially at low values. The different behaviour of the simplified model between the OT-MSF and RV-MSF configurations is attributed to the fact that brine recycling does not affect the feed temperature or the temperature distribution in the system.udemauteur: Mohammed Khennic
Social experience influences thermal sensitivity: Lessons from an amphibious mangrove fish
No full textUnderstanding the factors affecting the capacity of ectothermic fishes to cope with warming temperature is critical given predicted climate change scenarios. We know that a fish’s social environment introduces plasticity in how it responds to high temperature. However, the magnitude of this plasticity and the mechanisms underlying socially modulated thermal responses are unknown. Using the amphibious hermaphroditic mangrove rivulus fish Kryptolebias marmoratus as a model, we tested three hypotheses: (1) social stimulation affects physiological and behavioural thermal responses of isogenic lineages of fish; (2) social experience and acute social stimulation result in distinct physiological and behavioural responses; and (3) a desensitization of thermal receptors is responsible for socially modulated thermal responses. To test the first two hypotheses, we measured the temperature at which fish emerged from the water (i.e. pejus temperature) upon acute warming with socially naive isolated fish and with fish that were raised alone and then given a short social experience prior to exposure to increasing temperature (i.e. socially experienced fish). Our results did not support our first hypothesis as fish socially stimulated by mirrors during warming (i.e. acute social stimulation) emerged at similar temperatures to isolated fish. However, in support of our second hypothesis, a short period of prior social experience resulted in fish emerging at a higher temperature than socially naive fish suggesting an increase in pejus temperature with social experience. To test our third hypothesis, we exposed fish that had been allowed a brief social interaction and naive fish to capsaicin, an agonist of TRPV1 thermal receptors. Socially experienced fish emerged at significantly higher capsaicin concentrations than socially naive fish suggesting a desensitization of their TRPV1 thermal receptors. Collectively, our data indicate that past and present social experiences impact the behavioural response of fish to high temperature. We also provide novel data suggesting that brief periods of social experience affect the capacity of fish to perceive warm temperature.udemauteur: Simon Lamarr
Transformer for authenticating the source microphone in digital audio forensics
No full textIn recent years, digital audio has played a significant role in providing information used as evidence in criminal investigations. The authenticity of an audio recording must be proven for it to be admitted into evidence in a legal proceeding. In this paper, we propose a robust system based on transformer deep learning architecture for identifying the source microphone with high accuracy, which is applicable in digital audio forensics. To evaluate the proposed model, we use the Audio Forensic Dataset for Digital Multimedia Forensics (AF-DB) and the King Saud University speech database (KSU-DB) datasets. Experiments show that the proposed model achieves state-of-the-art classification accuracy on the two databases. The model achieves an overall accuracy of 94.18% and 84.19% for Inter-model and Intra-model microphone classification, respectively, for the AF-DB and 99.38% for the KSU-DB speech dataset.udemauteur: Sid Ahmed Selouan
Effets de la perméabilité du paysage et de la condition physique des individus sur le mouvement de parulines couronnées (seiurus aurocapilla) suivant une translocation expérimentale
No full text"Cette thèse visait à déterminer si la structure du paysage et la condition physique des individus ont un impact sur le taux de retour chez la Paruline couronnée (Seiurus aurocapilla) suite à une translocation expérimentale sur une distance de 24 à 27 km. Afin d'estimer la condition corporelle des individus, j'ai utilisé la méthode d'eau deutérée («hydrogen isotope-labeled water (D20)»). Cette technique consiste à injecter une quantité connue d'eau deutérée qui sera ensuite diluée par l'eau contenue dans l'oiseau, ce qui permet d'estimer l'eau corporelle totale, qui est elle-même étroitement liée à la masse maigre."