VictorJuiz/thesis huggingface dataset:
The Effect of Using Bioflocculants as Conditioners on Dewatering of Biosludge
Keywords: Bio-flocculant
Biosludge
Dewatering
Pulp Paper
Wastewater

Chemical conditioning by biopolymers, as an alternative for petroleum-based synthetic polymers, for improving the dewatering of biosludge from pulp and paper mills is a growing interest. There are limited studies on the application of biopolymers for enhancing the dewaterability of biosludge and the underlying mechanisms in this process. This thesis explored the possibility of employing biopolymers such as hemoglobin (Hb), lignin-based flocculants (LBFs), and protamine to enhance the dewaterability.Cationic polymers improve the dewaterability of sludge by neutralizing the negative charge of the biosludge particles. Biopolymers such as hemoglobin and lignin do not possess high charge density naturally. As a result, they only exhibit a positive effect on dewaterability after modification through different processes. Hemoglobin from animal blood was methylated to replace the hydrogen carboxyl groups in its structure to become more positively charged. Lignin from pulp manufacturing processes was also modified via free radical polymerization with acrylate-based monomers. Dewaterability was assessed based on the dry solids content after treatment and pressing by Crown press. Capillary suction time (CST) was also used as water separation rate indicator. Only after modification, by using 10% of methylated hemoglobin, the dry solids content of biosludge increased by 5%. Similarly, LBFs considerably decreased the CST by nearly 50 seconds from 73s to 23s and increased the dry solids content by 7% with a relatively high dose of 7.5%. The potential of using dual conditioning method by combining cationic biopolymers such as protamine and LBFs with a small amount of a synthetic anionic polyacrylamide (APAM) was also investigated to lower the dosage required for biopolymers. Dual conditioning provided significant synergistic effect resulting in increasing the solids content of biosludge by 9% and lowering the amount of protamine addition substantially to 2%. In a similar way for LBFs, the biopolymer demand decreased from 7.5% to around 3% by using a dual conditioning system. The cationic biopolymer reduced the negative charge on the particles, allowing smaller particles to agglomerate and provided a positively charged framework for the addition of the APAM. Significant floc-bridging occurred after the addition of APAM, allowing smaller flocs to aggregate into larger flocs.
Developing predictive stream fish productivity models using the metabolic theory of ecology and a size-based approach
Keywords: Fish ecology
Metabolic theory of ecology
Productivity
Size spectra
Stream fish

Secondary production reflects the amount of energy available to higher trophic levels and can provide insight into the dynamics of energy transfer within an ecosystem. Fish production incorporates a wide range of key response metrics such as abundance, biomass, growth, and reproduction, into one quantitative metric but requires resource-intensive data for empirical estimation. While many studies have investigated fish productivity, few have evaluated different methods of estimating production or investigated the key drivers of productivity in riverine ecosystems. Additionally, size spectrum modeling reflects the negative scaling relationship between abundance and body size and has commonly been applied to lake and marine ecosystems to understand trophic dynamics and the transfer of energy for communities and ecosystems. In my thesis, I investigate different approaches to predict the biomass production of stream fish assemblages using the metabolic theory of ecology and size spectrum modeling. By testing the metabolic theory of ecology and published standard production model, I show that precise estimates of total stream fish productivity can be obtained from biomass and body size data. To ensure that fish data are unbiased and accurately represent fish assemblage, I developed a capture probability model using a hierarchical Bayesian framework that corrects the size bias associated with electrofishing removal samples. I then used variance partitioning and model selection to investigate how a combination of abiotic and biotic variables are related to stream fish productivity in wadeable streams. Finally, I investigated the parameterization of size spectrum models at various spatial scales to determine whether site aggregation is a suitable approach for riverine size spectrum modeling. My findings indicate that fish size spectra align better approximate theoretical expectations when multiple sites are aggregated together. Overall, my thesis demonstrates that published standard fish production models can be used to estimate productivity, that productivity is better predicted by biotic than abiotic variables, and that size spectra models at broader spatial scales can be used to investigate the movement of energy at higher trophic levels in river ecosystems.
Under Surveillance: A Study of the Securitization of Somali Men in Canada
Keywords: Auto-ethnography
Islamophobia
Muslims
Securitization
Somali
Surveillance

This study uses an autoethnographic approach as a Somali, Black, Muslim, Woman living in Canada. Drawing on my lived experiences, I look at the ramifications and direct material consequences of islamophobia and anti-blackness on the Somali Toronto community. In addition, this also utilizes a Critical Discourse Analysis Approach to study anti-terrorism policy and countering violent extremism programs in Canada; it critically examines 10 key government documents that focus on radicalization and national security. A critical examination of these documents reveals anti-Islamic, Islamophobic, and Orientalist discourses embedded within national security policies. The findings show a clear contradiction between the Charter Rights and Freedoms and the current anti-terrorism policies, which have directly caused an increase in racial profiling and racialization of Muslims. The key arguments presented in this study show that the current approaches to address ‘terrorism’ stem largely from Orientalist ideas about the East and the fear of the ‘enemy.’ I emphasize the need for a multi-centric depiction of Muslims that disrupts the common monolithic construction of the violent, intolerant, Muslim Male. The response to 9/11 resulted in discourses and constructions of Muslim men as potentially dangerous and a threat to democratic values, which has contributed to the continual surveillance and securitization of Muslim communities in Canada. This study contributes to the broader discussions surrounding national security, Islamophobia, and securitization in Canada. I utilize an anti-racist, Foucauldian, and intersectional approach to look at the existing barriers Canadian Somali men face. Through situating the dual oppressions Canadian Somali men face, I argue a need for an anti-racist approach to countering violent extremism, and the importance of a multi-centric understanding of Islam. I introduce an integrative anti-framework approach that addresses the systemic barriers Somali men face in Canada.
“The Scars Remain.” Power, Solidarity, and Punishment in an Atypical Latin American Prison
Keywords: global south
leadership
prisoners participation
prisons
punishment

This dissertation presents an ethnographic research study of “Punta de Rieles,” an atypical Latin American prison where over 600 male prisoners coexist with a significant degree of autonomy in a relatively peaceful environment that resembles a poor neighbourhood. Unlike other experiences in the region, the atmosphere of this prison is a direct consequence of the prison authorities’ decision to promote responsibilization, prisoners' participation, and solidarity. The study explores this prison on its own social, geographical, and political terms, examining the discourses and rationalities that shape the warden's practices and leadership style. It describes how prisoners actively adapt and engage with the penal environment, shaping it through individual and collective participation. In this way, the penal environment, the governmental practices, the surveillance network, and the level of order are defined by the authorities and influenced by the prisoners. This study dialogues with prison sociology studies from the Global North and the Global South and sheds light on the fragility of penal regimes based on strong leadership, the impact of real subjects in defining penal scenarios, the limitations of responsibilization, the complex power assemblages that define punishment, the contradictions that arise when conflicting rationalities interact, the role of prisoner participation in establishing order, and the relationship between domination and space and time carceral configurations.
Role of Intracellular Calcium Stores and Calcium-Permeable AMPARs in Functional and Structural Plasticity in Mouse Hippocampal Slices
Keywords: Calcium
Calcium-permeable AMPA-receptor
Long-term potentiation
Protein synthesis-dependent plasticity
Synaptic tag and capture
Two-photon imaging

Memories are internal representations of life that can last in the order of minutes to years, and are largely experience-dependent. For example, the memory of an inconsequential event typically fades, unless they are closely related to a novel event, succinctly explained by the synaptic tag and capture (STC) hypothesis. The formation of short (STM)- or long - term memories (LTM) involve several biochemical changes that either increase or decrease synaptic efficacy. These changes are commonly referred to as Long-term potentiation (LTP) or depression (LTD). LTP can be differentiated into two forms based on their dependence (LTP2) or independence (LTP1) on protein synthesis (PS) and are hypothesized to be analogous to LTM and STM respectively. In both forms of LTP, calcium (Ca2+) signaling plays a vital role. However, Ca2+ has a number of different sources, the relative importance of which is poorly understood. Here I have investigated the role of calcium-permeable (CP)- AMPARs and Ca2+ release from intracellular stores. Using theta burst stimulation (TBS) of varied strength and patterning, I was able to selectively induce LTP1 (wTBS or cTBS) or a combination of LTP1 and 2 (sTBS). Combining these induction protocols with pharmacological agents, I have confirmed the role of CP-AMPARs and demonstrated that intracellular Ca2+ stores are required specifically for LTP2. To investigate STC, I delivered LTP 2 and LTP1 to independent inputs, which resulted in an enhancement of LTP1 due to STC. I confirmed the role of CP-AMPARs and demonstrated the importance of Ca2+ release from intracellular stores during the induction of LTP2 in STC. Furthermore, to address the question of the association between functional and structural plasticity under physiological conditions, I developed a method to monitor both simultaneously using field potential recordings and two-photon imaging, respectively. I found that functional plasticity induced by sTBS is associated with structural plasticity and that the structural plasticity is entirely dependent on the activation of CP-AMPARs. In conclusion, my findings provide novel insights to the synaptic basis of memory formation and highlight the importance of CP-AMPARs and calcium release from intracellular stores in this process.
Sperm Motion in Viscous Environments with Applications in Microfluidics-based Selection
Keywords: fertility
microfluidics
sperm

Male infertility is a major global concern and is defined by an ejaculate that’s function is hindered by insufficient sperm counts and/or low-quality sperm that obscure fertilization success. Assisted reproduction techniques (ARTs) are used to treat infertility and focus on the selection of viable sperm from the sample for fertilization in vitro. However, conventional selection methods fail to recover the top sperm candidates, thereby limiting ARTs success. The concerns of infertility and challenges in its treatment techniques indicate the necessity of sperm analysis and selection methods to resolve the mechanisms mediating fertilization success and to improve ARTs. Biomimicry-based models supporting key properties of the in vivo microenvironment are required – and microfluidics has emerged as a promising tool to meet this demand. This thesis develops clinically-driven microfluidic approaches for sperm selection and investigates sperm behaviour in relevant rheological environments. A sperm selection-in-a-dish platform is developed, integrating the clinically established petri dish with a microchannel array that selects high-quality sperm directly from semen by way of a one-stage processing protocol that is representative of the clinical setup for fertilization in vitro (Chapter 3). Clinical tests with human sperm show a 63% improvement in selected sperm DNA integrity over that of the standard methods. In the course of clinical test development, an unexpected cooperative behaviour among human sperm is discovered within a microfluidic setup mimicking the viscous contrasts in the female tract. Sperm with high DNA integrity cooperate by attaching at the head region to migrate faster as a group through highly viscous conditions to potentially outcompete rival sperm for fertilization. This new mode presents a revision on the knowledge of motion of human sperm – some of the most studied human cells – and became the focus of the second half of the Ph.D. (Chapter 4). The cooperative swimming mode preferentially involves sperm with high DNA integrity and capacitation functionality, and can be an essential mechanism dictating fertilization success and for incorporation in selection processes in ARTs. Collectively, these contributions advance the field of male fertility by providing new methods for sperm selection in vitro, and new understanding of how sperm navigate in vivo.
Visual Learning Using Synthetic Data
Keywords: Adversarial Learning
Computer Vision
Deep Learning
Domain Adaptation
Synthetic Data

Deep learning has revolutionized several fields, including computer vision. Yet, creating computer vision datasets to train deep neural networks using supervised learning is time-consuming and expensive, typically involving collecting and annotating large amounts of sensor data. This collection and annotation process becomes more complex and costly if the task demands risky events, highly precise annotation, or expert knowledge. Using synthetic data generated with graphics simulators for training deep neural networks is an alternative solution. We can obtain an infinite number of perfectly labeled training samples with synthetic data, including long-tail rare events and safety-critical scenarios, and those humans might annotate noisily. However, the generalization performance in complex real-world scenes of synthetic-data-trained models frequently degrades. This thesis presents a collection of work toward overcoming this issue. Our core idea interprets learning from data generated with graphics simulators as a domain adaptation problem and develops novel adaptation techniques that improve the transfer performance in real-world datasets. The underpinning of our proposed algorithms lies in aligning synthetic and real-world data distributions using a novel adversarial framework that minimizes a chosen f-divergence and is both practical and theoretically motivated. We also show how to deal with complications arising in this framework, such as complex optimization dynamics and label-distribution mismatch. We demonstrate the effectiveness of our methods in both controlled settings using standard datasets and in more practical scenarios using an open-source self-driving simulator with multi-sensor data. Finally, I conclude the thesis by summarizing the key contributions of my work and discussing directions for future research.
Expressive Virtuosity on Accordion: The Performance Techniques of Joseph Macerollo, O.C.
Keywords: Accordion
Draugsvoll
Jacomucci
Macerollo
Performance
Technique

Since the 1970s, Joseph Macerollo’s accordion teaching has attracted hundreds of students from at least 18 countries, and he has given hundreds of world premieres with an emphasis on contemporary chamber music. A pioneer of using accordion in a contemporary music landscape, Macerollo developed a multitude of precise body techniques for integrating the accordion’s sound into diverse musical environments. His techniques incorporate all parts of the upper body (and occasionally the legs) to achieve superior versatility and awareness in the performer’s production of tone, phrasing, articulation, projection, and the ability to alter how ‘time’ is perceived by the listener—all of which I call collectively Expressive Virtuosity. Macerollo summarizes his method in a four-point model—Time, Tone, Flow, and Space. Examples of his unconventional techniques include playing the left hand ahead of the right, using multi- dimensional bellowing motions, creating rhythmic points using combinations of finger, bellows, and body techniques, and moving around the instrument. These techniques have the potential to revolutionize how accordion is taught at the university level, and the central goal of this thesis is to document and explain Macerollo’s unconventional techniques. To offer additional perspectives on Expressive Virtuosity, I also conducted interviews with renowned Professors Geir Draugsvoll and Claudio Jacomucci, including in-depth discussions of performing as an orchestral soloist and using the Alexander Technique on accordion. The recent rise in articles related to accordion performance and pedagogy shows that the academic accordion community is searching for new techniques that will inspire greater creativity in relationships with composers, within pedagogy, and on the concert stage. After a lifetime of performance experience and teaching, Macerollo’s techniques will help raise concert accordion playing to the next level and acknowledge Canada’s most important contribution to date in this field.
Decoding and Reconstructing Orthographic Information from Visual Perception and Mental Imagery Using EEG and fMRI
Keywords: Decoding
EEG
fMRI
Reconstruction
Visual recognition

Vision plays a crucial role in reading by supporting the processing of visual-orthographic representations, which are essential for social interactions and daily activities. In recent years, there has been a lot of interest in investigating such processes across multiple methodological domains, including electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). For instance, studies have shown the importance of the visual word form area (vWFA) in reading, but its exact role remains unclear. On the other hand, mental imagery is a unique form of visual experience where, in contrast to perception, no external stimuli are present. The current thesis aims to investigate the neural representational structure of visual-orthographic information in both visual perception and mental imagery by considering both EEG and fMRI signals during word recognition and by applying state-of-the-art pattern analysis techniques to such signals. Specifically, Chapter 2 established the feasibility of decoding and reconstructing whole-word images from EEG data. The examination of the time course of decoding provided insight into the temporal dynamics of early word processing, identifying critical time points for word recognition. Chapter 3 examined the relative contribution of different time points from different EEG channels, revealing time and frequency features that underlie decoding for words and faces. Chapter 4 investigated the neural representational structure of words in mental imagery using fMRI and successfully decoded and reconstructed whole words from activity patterns in both vWFA and early visual cortex. These findings provide a deeper understanding of the neural mechanisms underlying visual perception and mental imagery of orthographic information. They demonstrate the feasibility of retrieving fine-grained visual features from neural signals that support the distinction of within-category exemplars, which offers considerable potential benefits for the development of new communication methods for individuals with communication impairments.
Statistics of the Synchrosqueezing Transform
Keywords: complex gaussian noise
synchrosqueezing
time-frequency analsis

We investigate the synchrosqueezing transform applied to complex gaussian white noise, as well as signals consisting of a single harmonic component contaminated with complex gaussian white noise. First, this involves analyzing the reassignment rule, which is built from a quotient of improper, correlated complex gaussians. We provide a new formula for the general density of said quotient and use this to carefully clarify the decay rate of the covariance of the reassignment rule. Next, for a fixed time $t$, we analyze the synchrosqueezing integrand $Y_{\alpha,\eta}$ at different frequencies $\eta$ and resolutions $\alpha$. A detailed asymptotic analysis of the covariance between $Y_{\alpha,\eta}$ and $Y_{\alpha,\eta'}$ is provided. By appealing to an $M$-dependent approximation argument, we obtain a central-limit theorem for the synchrosqueezing transform at time $t=0$ and fixed frequency $\xi$ and give an interpretation within the context of kernel regression. Finally, we provide a number of open problems whose resolution may lend themselves to further results in the vein of this work.
Crossroads in Digital Gaming: Metaplay, Communication, Interaction
Keywords: Canada Suburban play
Gaming capital
Metagame
Metaplay
Paratexts
Pokemon

This dissertation conducts a qualitative study in a region in Canada, anonymized as “the District”, which sits outside of a major city, focusing on adult players of the main series of Pokémon games. The District encompasses different geographic areas, characterized by suburban growth in a rural context with limited urban areas, with a significant industrial sector that comes with a working class demographic. By interviewing players who began playing Pokémon at different points in time, ranging from the first generation of players in 1998 to those who played their first Pokémon games in the mid-to-late 2000s, the dissertation captures a snapshot of changing play practices that came alongside the deployment of high-speed and more accessible Internet in the mid 2000s. Since the debut of Pokémon in North America in 1998, Pokémon play is now significantly more complex owing to an intricate network of gaming practices and communication, contextualized by play practice developments over time, changes in hardware, and information communication technology (ICT) infrastructure in local communities. This dissertation argues the best means of engaging digital play today is the framework of metaplay, derived from Bateson’s theories of meta-action and meta-communication (1956), supported by the components of metagame (Donaldson, 2016), paratexts, and gaming capital (Consalvo, 2007). Through this framework, the study reveals inequities in Pokémon play in the District, demonstrating the impact of infrastructure and perceptions of play for adult players in regions like the District, while also demonstrating a desire for local play cultures and how ICTs impact the complicated relationship local players have with global play cultures and practices.