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Logos, sin, and moral transformation in Origen’s De Principiis 3.1
Full text linkOrigen of Alexandria’s treatise on “self-determination” (De Principiis 3.1) has proven highly influential for subsequent theological and philosophical discussions of free will. There is still considerable debate about the finer points of Origen’s understanding of “self-determination” (to autexousion) and where his notion of it fits within the broader Ideengeschichte of free will. In this thesis I examine the free will treatise, but focus instead on the role of the Logos in his understanding of human freedom and moral transformation. In chapter one, I trace the historical development of the Logos concept from Heraclitus and the Stoics through Middle Platonism and the Biblical Platonists, particularly Philo and Clement of Alexandria, to provide a contextualization of Origen's doctrine. Then, on the basis of this contextualization, I argue (in chapters two and three) that Origen's Logos is not a neutral rational faculty but possesses a paraenetic quality, actively prompting moral agents toward virtuous action. By analyzing Origen's psychology of self-determination, especially his use of aphormē (“prompting”), I demonstrate how the Logos influences the moral choices of rational beings. In chapter four I articulate and motivate what I call the "problem of noetic sanctification" in Origen's theology, and in the fifth and final chapter I propose a solution to the problem on Origen’s behalf in which the Logos within each rational being provides a persistent, pre-cognitive motivation towards goodness, thereby facilitating noetic sanctification through interaction with Christ as the cosmic Logos and "light."May 202
Correction to: Scaling up access to antiretroviral treatment for HIV: lessons from a key populations program in Nigeria
Full text linkCorrection to: AIDS Research and Therapy (2025) 22:10 https://doi.org/10.1186/s12981-025-00711-
Salidroside protects against myocardial infarction via activating MIF-mediated mitochondrial quality control
Full text linkAbstract Background Salidroside is a potential therapeutic agent for myocardial infarction (MI), exerting therapeutic effects on macrophage migration inhibitory factor (MIF)-regulated mitochondrial quality control. Our aim was to explore the mechanism through which the MIF pathway regulates salidroside-mediated resistance to hypoxia-induced cardiomyocyte apoptosis. Methods Ligation surgery of the left anterior descending branch of the coronary artery was employed to establish a myocardial infarction mouse model. Salidroside at low and high doses was administered to the mice for 4 weeks after the surgery. Cardiac function was evaluated via echocardiography. Morphological changes, apoptosis, and mitochondrial damage in the myocardium were examined. For the cell experiments, cardiomyocytes were treated with salidroside under oxygen‒glucose deprivation (OGD) conditions and were either treated with recombinant MIF (rMIF) or transfected with Mif-siRNA. Subsequently, mitochondrial quality control and apoptosis were assessed. Results Salidroside enhanced mitochondrial quality control in MI model mice, mitigated apoptosis and improved cardiac dysfunction. Transmission electron microscopy indicated that there were fewer damaged mitochondria in the salidroside-treated mice compared with the control mice. MIF and downstream mitochondrial quality control pathways were activated in the mice treated with salidroside. Consistently, the cell experiments demonstrated that salidroside and rMIF alleviated apoptosis, improved impaired mitochondrial quality control in OGD-induced cells and activated MIF signaling in OGD-induced cells. However, these effects of salidroside were partially blocked by Mif-siRNA transfection. Conclusion Salidroside alleviated myocardial apoptosis and ameliorated cardiac dysfunction in MI model mice through the MIF pathway and downstream mitochondrial quality control
Rigidity properties of operator systems and partial order relations in the state space of C*-algebras
Full text linkArveson’s hyperrigidity conjecture concerns the unique extension property of *-representations of a C*-algebra with respect to a generating operator system. The maximal states in the dilation order fully encapsulate the cyclic representations of a C*-algebra with the unique extension property. A reformulation of the conjecture by Davidson and Kennedy raises the question whether the maximal measures in the dilation order are concentrated on a particular set. In this thesis, we address this question for general C*-algebras. We show the existence of a projection such that the dilation maximal states are precisely those states which are concentrated on the projection. We also reformulate the conjecture in terms of the non-commutative topological properties of this projection.
Choquet order is a partial order defined on the set of regular Borel probability measures on a compact convex set. With the help of two equivalent characterizations of Choquet order, we define strong dilation relation and sub-division relation on the state space of a C*-algebra. The equivalence of the two relations is not known in general. We show that the strong dilation relation is stronger than the sub-division relation. Moreover, we show the equivalence of the strong dilation relation with a non-commutative sub-division relation. We also demonstrate that these relations can serve as valuable tools for investigating certain rigidity properties of a generating operator system of a C*-algebra.May 202
Encouraging robust oil spill planning, preparedness, and response in Chesterfield Inlet, Nunavut, Canada
Full text linkArea-based oil spill plans such as community oil spill plans are essential for Arctic regions. The outcome of this project is the creation of a series of policy briefing notes based on consideration of Canadian policy and programs alongside those in Arctic jurisdictions outside of Canada. The project’s objective was aimed at “creating a policy brief on oil spill planning, preparedness, and response for Canadian Arctic communities”. Given the results of the document and literature review, the briefing notes focused on the following areas: Background Area Information, Monitoring Regimes, Training Regimes, Local Involvement Requirements, and Framework for a Community Oil Spill Response Company. Recommendations in each of these areas are applicable to the Canadian Eastern Arctic community context. Some of the project’s main findings include the use of background information as a reference point/resource to inform area-based monitoring and training regimes. Regarding local involvement, it is suggested that a community advisory council/board would promote community-led oil spill planning, preparedness, and response tasks, such as risk assessments and knowledge exchange (oil spill response experience). A regional oil spill response company should be established that emphasizes community to community agreements (based on a hub structure). This would require ship/vessel owners to enter into response agreements with the company. The detailed briefing notes and recommendations are focused on local involvement and will help to inform Arctic communities, such as Chesterfield Inlet, and all levels of government about actions that are essential to improve the oil spill planning, preparedness, and response capabilities.May 202
Technology facilitated arts-based school counselling: a scoping review of the literature
Full text linkWith the rapid change in technology and the increasing mental health needs of children, school counsellors have had to adapt their practices accordingly (Bang et al., 2021). Combining creative arts interventions and technology may be a viable and effective adaptation for school counsellors to meet the needs of their 21st century students (Zubala et al., 2021; Zeevi, 2021) and may also enhance student motivation for engaging in the counselling process. Integrating arts-based technological interventions into the school counselling context is a way that students’ thoughts, emotions, and feelings may be accessed and/or expressed in different formats to assist school counsellors in supporting students’ mental health. Incorporating technological tools into arts-based interventions adds another dimension to the school counsellor’s role. To better understand how arts-based technological tools (ABTT) are being used by school counsellors, a scoping review was done to determine relevant themes in the existing research. Searches of APA PsycINFO, Web of Science and Scopus databases were done using keywords centering on school counsellors and interventions using the creative arts/arts-based interventions and technology. Supplementary articles were identified through reference lists and manual searching of relevant journals. 679 references were retrieved, with an additional 20 from handsearching other sources. 13 full-text articles met the inclusion and exclusion criteria. Findings of the scoping review indicated several benefits and challenges of ABTT, highlighting the need for professional development for school counsellors and an understanding of if and how an ABTT can really enhance their practice based on the students that they serve. Limitations of the review are identified as well as implications and future directions for research.Susan Williams Peet ScholarshipMay 202
A frequency-dependent virtual impedance approach to improving stability with grid-forming inverters
Full text linkGrid-forming inverters have gained significant attention for their ability to improve stability in weak and islanded power systems; however, the full extent of their potential benefits for the future bulk power system remains uncertain. One potential benefit is increasing stability margins in regions affected by inverter-driven instabilities, such as series-compensated areas within the ERCOT system. This thesis explores their potential in mitigating Wind Sub-Synchronous Control Oscillations (W-SSCI) in series-compensated systems with Type-3 wind plants when a grid-forming configured battery plant is co-located with the wind plant. A novel frequency-dependent virtual impedance (FDVI) controller is proposed to improve the performance of grid-forming battery energy storage systems (BESS). Comparative analyses of grid-forming and grid-following inverters are performed to evaluate their damping capabilities.
This thesis includes the development and verification of models in EMTDC/PSCAD, incorporates impedance scanning, eigenvalue analysis, and time-domain simulations, with the objective of quantifying the minimum capacity of grid-forming BESS needed to provide stability. The results indicate that grid-forming BESS can provide substantial damping to mitigate W-SSCI, even under severe series compensation scenarios. The FDVI controller further reduces the required BESS capacity by up to 45\%, demonstrating improved stability through targeted conductance tuning.
Conversely, grid-following BESS inverters are found to be unsuitable for W-SSCI mitigation because of their low admittance at sub-synchronous frequencies and susceptibility to instability under high gains or large BESS ratings. The findings strongly support the adoption of grid-forming inverters as a cost-effective solution for stability-constrained regions, offering superior damping performance compared to conventional technologies.May 202
Optimization of in vitro RNA interference assays to reduce variability in target gene knockdown in the phytopathogen Sclerotinia sclerotiorum
No full textSclerotinia sclerotiorum is a broad host range fungal phytopathogen that is the causal agent of Sclerotinia stem rot in many crop plants, causing devastating yield losses worldwide. Sclerotinia is partially controlled using broad-spectrum chemical fungicides, but new, more species-specific fungicides, such as double-stranded RNAs, are being considered as safer alternatives. This study evaluated the effectiveness of long double-stranded RNAs (dsRNAs) and paperclip RNAs (pcRNAs) to induce gene silencing in two different fungal inoculants of S. sclerotiorum. The three different genes that were targeted in this study, SS1G_01703, SS1G_00005, SS1G_14116, are all involved in different aspects of S. sclerotiorum’s infection process i.e. pathogenicity, encoding 60S ribosomal unit and mycelial growth respectively. Initial dsRNA experiments using small fungal plugs collected from solid media generally resulted in highly variable levels of transcript knockdown, potentially arising from unequal hyphal amounts in treatment tubes. This led to the development of fungal slurries as the inoculum to provide a more uniform distribution of hyphae across all the samples. The slurry method resulted in significant transcript knockdowns using all three long dsRNAs at different doses, although some variability persisted. The variability using the slurry method was linked to potential differences in hyphal developmental stages, age of hyphae and differences in expression levels of each target gene. In contrast, structurally different and shorter in length pcRNAs failed to induce consistent transcript knockdown in both plug and slurry assays, despite earlier reports of their efficacy in reducing lesion sizes on canola leaves. This inefficacy may stem from pcRNAs' reliance on a single siRNA for gene targeting, potentially insufficient to overcome the structural complexity of target mRNAs. These findings highlighted the potential of long dsRNAs for gene knockdown in S. sclerotiorum using optimized slurry-based assays, while suggesting that pcRNAs require further modifications. Future work can explore alternative siRNA designs, increased pcRNA doses, and identifying accessible mRNA regions to improve knockdown efficiency. Additionally, optimizing the methods to assess hyphal developmental stages and minimizing variability during sample preparation are crucial for reproducibility and accuracy in RNAi-based studies.May 202
Exploring the attentional cycling model of mind wandering through the lens of time perception
No full textAttentional cycling is the adaptive system that allows for individuals to evaluate whether their thoughts, goals, and behaviors are aligned. However, the specific cognitive mechanisms behind controlling and monitoring the shifting of attentional states is largely unknown. The answer might rely on the mechanisms behind another aspect of cognition, time perception. Where the pacemaker-accumulator model of time perception proposes that there are pulses emitted by a pacemaker and that an accumulator counts the pulses and gives us our sense of time perception. These pulses might also serve as a trigger to switch an individual’s attentional focus. Therefore, it is important to investigate whether the same mechanisms that control time perception, also control mind wandering and attentional cycling. This was investigated through two experiments, with the first replicating and validating the starfield color tracking task, which was used to manipulate subjective time perception, and we will use the sustained attention to response task to measure mind wandering and see if there is any relationship(n=166). The second is an experimental approach where we adapt the starfield color tracking task to resemble more traditional attentional tasks while still manipulating time perception and measuring mind wandering in the same task (n=103). In experiment 1, we used linear mixed effects models to find that time perception was successfully manipulated through this task and that our sense of time duration was related to mind wandering. In Experiment 2, we used factorial ANOVAS to show that manipulated time perception was able to influence our off-task thoughts. We also find various relationships with trait-level measures, further strengthening the claim that they are connected somehow. Overall, these results imply that the mechanisms underlying time perception also influence our rates of mind wandering and off-task thoughts, but they do not specify which potential model of time perception is the correct one.February 202
Accelerating high-throughput proteomics with proteome-selective isolation chromatography (P-SLICY)
No full textProteomics is one of the most effective ways to study protein regulation including characterizing the changes in protein quantity as a result of biological perturbation. Liquid chromatography paired with tandem mass spectrometry (LC-MS/MS) is the most commonly used analytical technology in this field. After two decades of technological advancements, the quantitation of the total human proteome still precludes us. These advancements have allowed for high throughput quantitation of near tens of thousands of proteins in hours of analysis time. However, 30% of the proteome remain elusive in routine proteomic analysis. Current LC-MS/MS methods rely on increasing the number of peptides identified to yield more protein identifications. But it has been shown by Bekker-Jensen et al. that this is a logarithmic relationship with diminishing returns.
This diminishing return is because a majority of the peptides belong to high abundance or large proteins and are highly redundant. Prior peptide-centric approaches have shown promising improvements to proteome coverage by enriching a subset of peptides containing specific amino acids for analysis rather than analyzing the whole digested proteome. By reducing the number of peptides necessary to analyze and the overall protein identification redundancy, these approaches can potentially bypass the logarithmic relationship between peptide and protein identifications. We aim to develop a peptide-centric approach that can be generally applicable for a variety of sample types by enriching a subset of peptides that have a particular physicochemical property via chromatographic approaches. Therefore, our approach is named Proteome-Selective Isolation Chromatography (P-SLICY). In this thesis, we will describe the fundamental topics within proteomics, chromatography, and mass spectrometry and the innovations towards understanding peptide chromatography to develop P-SLICY.February 202