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Surface morphology characterization of industrial zinc electrodeposits as a function of chemical additives using atomic force microscopy and scaling analysis
Get PDFThe influence of chemical additive and deposition time on the morphology of short-time zinc electrodeposits was studied using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and scaling analysis. SEM and AFM were utilized to capture high-resolution images of zinc samples produced between 10 and 90 minutes of deposition from an electrolyte with a composition similar to that being used in the industry. Scaling analysis of the 3D AFM images was used to quantify surface roughness including root-mean-squared (rms) roughness, feature widths, roughness to width ratios, and their rates of change. Insight on the growth mechanism for these short-term deposits was achieved using scaling analysis. Within the deposition conditions studied, results showed that zinc deposit morphology is influenced by the relative proportions of bone glue, sodium silicate and licorice additives
Markov blanket: efficient strategy for feature subset selection method for high dimensionality microarray cancer datasets
No full textCurrently, feature subset selection methods are very important, especially in areas of application for which
datasets with tens or hundreds of thousands of variables (genes) are available. Feature subset selection
methods help us select a small number of variables out of thousands of genes in microarray datasets for a
more accurate and balanced classification. Efficient gene selection can be considered as an easy computational hold of the subsequent classification
task, and can give subset of gene set without the loss of classification performance. In classifying
microarray data, the main objective of gene selection is to search for the genes while keeping the maximum
amount of relevant information about the class and minimize classification errors. In this paper, explain the
importance of feature subset selection methods in machine learning and data mining fields. Consequently,
the analysis of microarray expression was used to check whether global biological differences underlie
common pathological features in different types of cancer datasets and identify genes that might anticipate
the clinical behavior of this disease. Using the feature subset selection model for gene expression contains
large amounts of raw data that needs analyzing to obtain useful information for specific biological and
medical applications. One way of finding relevant (and removing redundant ) genes is by using the
Bayesian network based on the Markov blanket [1]. We present and compare the performance of the
different approaches to feature (genes) subset selection methods based on Wrapper and Markov Blanket
models for the five-microarray cancer datasets. The first way depends on the Memetic algorithms (MAs)
used for the feature selection method. The second way uses MRMR (Minimum Redundant Maximum
Relevant) for feature subset selection hybridized by genetic search optimization techniques and afterwards
compares the Markov blanket model’s performance with the most common classical classification
algorithms for the selected set of features. For the memetic algorithm, we present a comparison between two embedded approaches for feature subset
selection which are the wrapper filter for feature selection algorithm (WFFSA) and Markov Blanket
Embedded Genetic Algorithm (MBEGA). The memetic algorithm depends on genetic operators (crossover,
mutation) and the dedicated local search procedure. For comparisons, we depend on two evaluations
techniques for learning and testing data which are 10-Kfold cross validation and 30-Bootstraping. The
results of the memetic algorithm clearly show MBEGA often outperforms WFFSA methods by yielding
more significant differentiation among different microarray cancer datasets. In the second part of this paper, we focus mainly on MRMR for feature subset selection methods and the
Bayesian network based on Markov blanket (MB) model that are useful for building a good predictor and
defying the curse of dimensionality to improve prediction performance. These methods cover a wide range
of concerns: providing a better definition of the objective function, feature construction, feature ranking,
efficient search methods, and feature validity assessment methods as well as defining the relationships
among attributes to make predictions. We present performance measures for some common (or classical) learning classification algorithms (Naive
Bayes, Support vector machine [LiBSVM], K-nearest neighbor, and AdBoostM Ensampling) before and
after using the MRMR method. We compare the Bayesian network classification algorithm based on the
Markov Blanket model’s performance measure with the performance of these common classification
algorithms. The result of performance measures for classification algorithm based on the Bayesian network
of the Markov blanket model get higher accuracy rates than other types of classical classification algorithms
for the cancer Microarray datasets.
Bayesian networks clearly depend on relationships among attributes to make predictions. The Bayesian
network based on the Markov blanket (MB) classification method of classifying variables provides all
necessary information for predicting its value. In this paper, we recommend the Bayesian network based on the Markov blanket for learning and classification processing, which is highly effective and efficient on
feature subset selection measures
The 0 -1 multiple knapsack problem
No full textIn operation research, the Multiple Knapsack Problem (MKP) is classified as a
combinatorial optimization problem. It is a particular case of the Generalized Assignment
Problem. The MKP has been applied to many applications in naval as well as financial
management. There are several methods to solve the Knapsack Problem (KP) and
Multiple Knapsack Problem (MKP); in particular the Bound and Bound Algorithm
(B&B). The bound and bound method is a modification of the Branch and Bound
Algorithm which is defined as a particular tree-search technique for the integer linear
programming. It has been used to obtain an optimal solution. In this research, we provide
a new approach called the Adapted Transportation Algorithm (ATA) to solve the KP and
MKP. The solution results of these methods are presented in this thesis. The Adapted
Transportation Algorithm is applied to solve the Multiple Knapsack Problem where the unit profit of the items is dependent on the knapsack. In addition, we will show the link
between the Multiple Knapsack Problem (MKP) and the multiple Assignment Problem
(MAP). These results open a new field of research in order to solve KP and MKP by
using the algorithms developed in transportation
La reconnaissance des expressions faciales émotionnelles chez les enfants : traitement par traits ou holistique
No full textLes recherches démontrent que les adultes reconnaissent certaines expressions faciales émotionnelles telles que la joie, la colère, la tristesse, le dégout, la peur et la surprise à des niveaux supérieurs à ceux attribuables au hasard. Toutefois, le taux de reconnaissance varie en fonction de l’émotion. De plus, certains travaux suggèrent que la reconnaissance implique un processus holistique lors du traitement de l’expression faciale alors que d’autres suggèrent un processus par traits. Beaudry et al. (2014) démontrent que chez les adultes, la bouche est nécessaire et suffisante pour la reconnaissance de la joie et les yeux et les sourcils le sont pour la tristesse. La peur nécessite un traitement holistique alors que les processus sont moins clairs pour les autres émotions. Chaque enfant est exposé à 5 conditions (le visage complet, le visage complet avec les yeux et les sourcils cachés, le visage complet avec la bouche cachée, les yeux et les sourcils seulement et la bouche seulement) et doit reconnaître l’émotion. Pour la reconnaissance des visages complets, les enfants de 10 ans sont meilleurs que les enfants de 5 ans à reconnaître le dégout et la surprise. Lorsqu’on présente seulement les yeux et les sourcils, les enfants de 10 ans sont meilleurs que les enfants de 5 ans à reconnaître la joie et la surprise. Pour la condition d’un visage complet avec les yeux et les sourcils cachés, les enfants de 10 ans sont meilleurs que les enfants de 5 ans à reconnaître le dégout, la peur et la surprise. Pour la condition d’un visage complet avec la bouche cachée, seule la joie est plus reconnue pour les enfants de 10 ans. Ces résultats suggèrent une évolution développementale dans le traitement et la reconnaissance des expressions faciales émotionnelles.Undergraduate These
Characterization of the relationship between two RBM5 family members
No full textRNA binding proteins (RBPs) control all aspects of RNA metabolism, and a single RBP can
have numerous downstream effects. Alterations to their expression and/or function can,
therefore, have remarkable consequences. For instance, decreased levels of the RNA binding
motif domain (RBM) protein RBM5 are associated with increased risk of a number of cancer
types, and RBM10 mutations can be lethal. Although these consequences are quite severe, little is
known regarding the range of processes and events influenced by these two homologous RBPs.
In fact, previous RBM5 and RBM10 functional studies were largely focused only on their
abilities to promote two processes; apoptosis and cell cycle arrest. Potentially by control of these
processes, RBM5 and RBM10 were shown to influence one event: differentiation. The objectives
of this study were to identify all cellular processes and events enriched by changes in RBM5
and/or RBM10 expression in a particular cultured cell line, and to determine the extent of
functional overlap for RBM5 and RBM10 in these cells. Towards these goals, a list of RBM5 and
RBM10 mRNA targets and differentially expressed genes was determined using next generation
sequencing techniques. Our data suggest that RBM5 and RBM10 do influence a wide range of
cellular processes and events. Although there is overlap in RBM5 and RBM10 mRNA targets and
differentially expressed genes, these RBPs can have antagonistic functions; for example our data
suggest that RBM5 prevents the transformed state, whereas RBM10 actually promotes it in an
RBM5-null environment. Furthermore, we present a working model by which RBM5 may
regulate RBM10’s protransformatory function. Finally, we demonstrate a relationship between
RBM5 and RBM10 in non-transformed cells. The results presented herein provide insight not
only into the roles and regulation of RBM5 and RBM10, but of RBPs in general. Taken together,
the results presented in the four papers included in this thesis expand the knowledge base of
RBM5 and RBM10, which provides insight into the disease states associated with their disrupted
expression or function. Our findings are thus relevant to a wide range of scientific fields
including molecular, developmental and cancer biology
Self-reported eating behaviour, physical activity, and learning engagement of Grade 3 and 6 students during the school day.
No full textBackground: The school environment is an important contributor to children’s health. This thesis
assessed student perceptions of physical activity, eating behaviors, and learning engagement
throughout the school day.
Methods: Surveys were distributed in grades 3 and 6: three schools using the Balanced School
Day (BSD) schedule, and three using the Traditional School Day (TSD) schedule. Students selfreported
physical activity, eating behavior, and learning engagement, at key times in the school
day. Student perceptions by grade, gender, and schedule were examined. Data were expressed as
frequencies and percentages and the variables were cross-tabulated and analyzed using Chi-
Square analyses.
Results: In total, 173 students participated in this study (response rate of 54%). Girls self reported being less physically active than boys at recess. Grade 3 students experienced hunger
more frequently than grade 6 students. There were no significant hunger or physical activity differences
between schedule types. All students reported high hunger and lower learning engagement
at the end of the school day.
Conclusion: We recommended age/gender specific schedule modifications to reduce hunger, and increase physical activity and learning engagement at school
Investigation into the cause(s) of a mass mortality of a long-lived species in a Provincial Park and an evaluation of recovery strategies.
No full textMass mortality events (MMEs) are rapidly occurring and localized events, and have been
reported to remove up to 90% of individuals in a population. MMEs can be especially damaging
to population persistence for long-lived species, such as chelonians. While MMEs have been
regarded as rare events, they are predicted to occur with increased frequency as environmental
stochasticity associated with climate change increases. Unfortunately, a limited understanding of
the causes and consequences of MMEs remains. In the current thesis, I investigated the potential
causes of an acute MME of at-risk Blanding’s turtles (Emydoidea blandingii) at Misery Bay
Provincial Park on Manitoulin Island, Ontario in which approximately 50% of the population
succumbed to mortality, and used population viability analyses (PVAs) to examine strategies to
recover the population. Because the park includes relatively pristine habitat in which most of the regular anthropogenic threats to turtles are absent, the hypotheses I tested to explain the mortality
considered natural threats, including disease, failed overwintering, and predation in the winter
and active seasons. I determined that the most likely cause of death was a large-scale predation
event, which received support from several lines of evidence, including the presence of predators
within the park, a failed predation attempt on a live Blanding’s turtle, and the meticulous
destruction of a turtle decoy stationed where carcasses were found. The recovery strategies
examined included nest protection, introduction of juveniles, introduction of adults, and a nest
protection plus introduction of juvenile combination strategy. PVAs determined that the most effective recovery strategy for this population would be a combination of nest protection and the
annual introduction of 25 two-year-old females for a period of 50 years. The information gained
through my study has led to the recommendation of appropriate conservation strategies for this
population, and will aid in the management of future MMEs elsewhere
La promotion de la santé mentale par le biais du développement des compétences psychosociales: le cas des adolescents franco-ontariens de l’École secondaire catholique Champlain
No full textLa question de la santé mentale des adolescents de 14 à 18 ans fréquentant
l’école secondaire retient l’attention de plusieurs, dont les conseils scolaires, les
directions d’écoles, les professionnels, les parents et le grand public.
Mondialement, il a été reconnu par l’Organisation mondiale de la santé (OMS,
2014) que la première cause de maladie est la dépression tandis que le suicide
représente la troisième causant le décès pour les 10 à 19 ans. Quoique
préoccupantes, ces statistiques ne doivent pas pour autant faire ombrage aux
formidables potentiels de ces jeunes en considérant les nombreux changements
biopsychologiques auxquels ils sont confrontés.
La promotion et la prévention en santé mentale restent un levier des plus
importants pour favoriser le mieux-être des jeunes. À cet effet, un programme
d’intervention de petit groupe sur les compétences psychosociales auprès des
élèves de 10e année fut conçu conformément au programme ministériel Stratégie
ontarienne globale de santé mentale et de lutte contre les dépendances avec
son 3e objectif : repérer très tôt les problèmes en santé mentale et de
dépendance afin d’intervenir précocement.
Ce programme sur les compétences psychosociales a été créé pour une
clientèle adolescente ayant des problèmes d’estime de soi et de socialisation,
mais il peut être utilisé pour d’autres problématiques. En résumé, les
interventions sur les CPS ont démontré leur efficacité dans l’intervention de petit
groupe pour prévenir des troubles de comportements et de santé mentale,
d’adaptation, d’empowerment, d’isolement, d’estime de soi, de relations
interpersonnelles, de consommation, etc.aitrise en service socia
“Mother first, student second”: challenging adversity and balancing identity in the pursuit of university-level education as First Nations mothers in Northeastern Ontario
No full textThe literature surrounding the educational experiences of Indigenous Peoples is an ever-growing and diverse area of research in Canada. However, within this field, the voices of First Nations mothers attending post-secondary needs further development. Through a decolonizing methodology and the use of autoethnography and Indigenous storytelling, this project was designed to explore and better understand our experiences as First Nations student-mothers during the pursuit of university-level education while caring for our children. I argue that Canada’s oppressive history of colonialism and the resulting intergenerational trauma have had specific implications on the post-secondary experiences of the First Nations mothers who participated in this research. The First Nations student- mothers from Laurentian University in Sudbury, Ontario, Canada who contributed to this research tell diverse stories about their experiences however, our narratives intersect in several ways. Areas of interest that emerged from the collected narratives include: (1) how we, as First Nations student-mothers have overcome obstacles, including what difficulties arose for us in the decision to pursue post-secondary education; what motivators contribute to our ongoing success, and how we experience self-doubt and internalized oppression despite our achievements and (2) how we, as First Nations student-mothers have blended our identities as First Nations women, mothers, and students within the university experience. Ultimately, this project aimed to contribute to continued efforts towards decolonization while furthering Indigenous-led research which hopes to improve the educational outlook for future generations of First Nations mothers
Experimental and correlational evidence that biological systems are influenced by intensity and variation of geomagnetic fields
No full textFluctuations in the Earth’s geomagnetic environment have been implicated in numerous biological processes as small as ion transport across a cellular membrane to as gross as the activity and behaviour of an individual. Treatment of demyelinated planaria with a six minute exposure to a magnetic field which simulates the onset of a geomagnetic storm resulted in a reduction of atypical behaviours that mimics observations of planaria not treated with a demyelinating agent. There was also a strong correlation observed between the North/South component of the Earth’s geomagnetic field and the prevalence of multiple sclerosis around the world. Increases in the local geomagnetic field strength due to geomagnetic disturbances can also influence the electrophysiological and negatively impact the sporting performance of athletes. These results indicate that biological systems are heavily influenced by changes in their geomagnetic environment, and certain disease acquisition and progression may be intrinsically tied to these energies