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Polarons in DPP Polymers – How Glycol Side Chains and Elongated Conjugated Backbone Influence the Formation and Transport
Get PDFUnderstanding polaron formation in conjugated polymers is critical for advancing solid‐state organic electronics. Here, we investigate diketopyrrolopyrrole (DPP)‐based polymers with tailored side chains to elucidate the impact of glycolation on charge transport and polaron formation. We demonstrate that glycol side chains enhance p‐type character and charge carrier density, while backbone elongation improves planarity and mobility. Electrochemical doping using a semicrystalline solid‐state ionic liquid (SSIL) can increase conductivity by four orders of magnitude. In situ field‐dependent Raman spectroscopy probes polaron formation, showing increased π‐electron redistribution in glycolated DPP. Polaron formation of the DPPT‐T conjugated backbone shows a more localised polaron with structural changes to the thiophene donor unit. Backbone elongation results in greater polaron delocalisation with lower reorganisation energy. Finally, ion‐gel gated organic synaptic transistors (IGOSTs) demonstrate significant performance gains for glycolated polymers with gDPPT‐T and gDPPT‐TVT exhibiting strong excitatory post‐synaptic currents. The more facile polaron formation pathway for gDPPT‐TVT offers a significant advantage in the dynamics of ion migration and retention. This work provides molecular‐level insight into the incorporation of glycol side chains to high‐performance conjugated polymers for solid‐state applications
DNA Hypermethylation of the ZNF382 Promoter Region and Low mRNA Expression of ZNF382 Promote Diffuse Large B‐Cell Lymphoma Occurrence and Progression
Get PDFBackground: The pathogenesis of diffuse large B‐cell lymphoma (DLBCL) remains unclear. Zinc finger protein 382 (ZNF382) expression is significantly downregulated in DLBCL, which is associated with poor prognosis. However, the underlying mechanisms remain unknown. Aims: To investigate the association between DNA methylation of the promoter region of ZNF382 and ZNF382 expression with the occurrence and progression of DLBCL and to analyze the clinical significance of ZNF382 in DLBCL. Methods and Results: DLBCL cell lines and reactive hyperplastic lymph node tissues were used as the experimental subjects. Methylation‐specific polymerase chain reaction and reverse‐transcription polymerase chain reaction analyses revealed significantly higher methylation of the promoter region of ZNF382 (p < 0.0001), whereas ZNF382 mRNA expression was significantly lower (p < 0.01) in DLBCL cells compared with those in reactive hyperplastic lymph node tissues. Cells were treated with the demethylating agent decitabine (DAC), and the methylation status of the promoter and expression levels of ZNF382 were determined. ZNF382 promoter methylation was significantly reduced (p < 0.01) in DLBCL cells, whereas ZNF382 mRNA expression was significantly increased (p < 0.01) compared with those in the control cells. Furthermore, compared with that in the blank control group, the apoptosis rate of DLBCL cells was significantly increased following DAC intervention (p < 0.01). A cell model of ZNF382 overexpression was constructed, and its proliferation, migration, and clonogenic capacities were detected using CCK‐8, Transwell, and soft agar assays, respectively. Compared with those of the vector control group, the cell proliferation, migration, and clone formation abilities of the ZNF382 overexpression group were significantly inhibited (p < 0.01). Conclusion: DNA hypermethylation in the promoter region of ZNF382 and low ZNF382 mRNA expression are closely related to the occurrence and progression of DLBCL. Moreover, ZNF382 overexpression significantly increased apoptosis and inhibited cell proliferation, migration, and clone formation. Therefore, ZNF382 has potential as a therapeutic target in the treatment of DLBCL
stGCL: a versatile cross-modality fusion method based on multi-modal graph contrastive learning for spatial transcriptomics
Get PDFAdvances in spatial transcriptomics have enabled high-resolution mapping of tissue architecture at the molecular level, yet integrating its multi-modal data remains challenging. Here, we present stGCL, a framework for accurate and robust integration of gene expression, spatial coordinates, and histological features. stGCL employs a histology-based Vision Transformer to extract morphological features and a multi-modal graph autoencoder with contrastive learning for cross-modal fusion. In addition, we introduce a spatial coordinate correction and registration strategy to support multi-slice integration. We demonstrate that stGCL reliably identifies spatial domains, integrates vertical and horizontal tissue slices, and highlight its generalizability across platforms and resolutions
Paradigms of water governance: a systematic review
Get PDFWater resources face critical challenges globally, and the current water crisis is often described as a crisis of governance, meaning that ideas about water governance matter greatly. We argue that so-called water governance paradigms play crucial roles in shaping policy agendas, influencing decision-making processes, and ultimately determining the success or failure of water management strategies. However, why, how, and where policy paradigms matter remains unclear. To address this research gap, we performed a systematic review of studies focused on water governance paradigms, examining (1) the characteristics of this literature and (2) how and which aspects of these paradigms are studied. An analysis of 100 studies reveals that the “integrated approach to governing/managing water” paradigm is a central concern in academic literature. The role of governmental actors in promoting and implementing paradigms, as well as the existence of imbalances in water governance debates, also features prominently. The studies we analyze highlight a discrepancy between the promoted paradigms and the contextual realities, compounded by the problem of institutional layering, whereby older paradigms persist and influence actual levels of change. Finally, our results show that although many studies adopt a critical perspective, few provide empirical evidence of paradigms’ effects, and there is a lack of common terminology. Overall, this review underscores the importance of problematizing water governance paradigms, which serve as a source code for governance arrangements. It also emphasizes the need to consider contextual nuances when engaging with these paradigms
Silicosis and the state: valuing life and labour in contemporary India
No full textThis thesis is an ethnography of a state welfare scheme for communities affected by silicosis, a lung disease caused by hazardous working conditions, in Rajasthan, India. It examines the different normative frameworks and political logics that have informed the creation, everyday operations of, and people’s experiences of the government compensation programme for occupational disease. Based on sixteen months of participant observation in a stone-carvers’ trade union and an NGO-run health clinic, this thesis provides an account of how activists, trade unionists, workers, bureaucrats, and doctors understand and negotiate state recompense for silicosis. The first part of this thesis traces the moral reasonings that underpin different forms of monetary restitution to injured workers. In the second part, this thesis shows how moral and political logics shape how people experience social protection programmes, and demonstrates that moral values are also vehicles through which activists can contest the limitations of state welfare for informal workers. This thesis challenges understandings of welfare that focus solely on how such programmes are constituted and designed, by drawing attention to the moral values and political contestations through which welfare is given meaning. It argues that while the opaque and inaccessible nature of the programme constrained activists and claimants, it also generated a fertile ground within which informal workers organising in trade unions could mobilise. It shows how informal workers and activists leveraged their position to make expansive demands for the regulation of factories, to contest medical determinations of their illness, and to craft relations of mutual aid among workers of diverse castes and tribes. This threads the underlying moral logics of welfare together with the aspirations of activists seeking to exceed bureaucratic rationalities and make wider claims for justice
Beginning again in heroics: the waste of rhetoric in Centlivre’s The Busy Body
No full textIn this essay, I argue that Susanna Centlivre’s The Busy Body (1709) actively concerns itself with the very distinctions between literature and theater, art and entertainment, mind and body, and the verbal and the visual that would ultimately result in Centlivre’s cultural eclipse. What became apparent to me while working on the play with a company of professional actors was not only the different registers of the comedy’s theatrical language—we might almost say its different genres—but also the manner in which the recurrent and bathetic discordances between these competing registers work to disclose their varying orientation to the body’s capacities and presence. Its comedy unfolds through the repeated ludic collision of, on the one hand, an ornate and avowedly male rhetoric that seeks chiefly to advertise its own virtuosity, and, on the other, the inventive, practical, and somatically centered mode of interacting and reacting consummately modelled by the play’s heroine. The Busy Body may not exhibit the kinds of word play so often (and problematically) regarded as the quintessence of Restoration comedy and indeed the basis of its literary value, but it does play with words and the very idea of what they do or don’t do. In short, it is a play about what we have come to call “literariness.
The lives of machines and screens: modern technical artefacts among the Yagua people in northwestern Amazonia
Get PDFThis thesis explores how modern technical artefacts alter the wider relational ecology of the Yagua people in northwestern Amazonia. Based on ethnographic fieldwork conducted between 2021 and 2023 in different Yaguan communities along the Orosa and Atacuari Rivers in Peru, it provides a detailed examination of the provenance, meanings, and ramifications of modern technical artefacts among the Yagua people. The thesis highlights in particular how modern technical artefacts are creatively integrated into Yaguan mythologies, ontologies, and everyday lives and shows that machines and screens – like other beings – are among the Yagua animated by plural, complex, and potentially ubiquitous life forces. It constitutes the first major anthropological study of the Yagua in the twenty-first century.With modern technical artefacts proliferating at a rapid pace across Amazonia, it offers a pertinent contribution to the wider anthropological literature on the political economy and developmental trajectory of lowland South America. As the thesis shows, machines and screens self-perpetuate through the transformation of human needs, hopes, and desires, and their spread fosters structures of dependency, reinforces an exploitative capitalist system, and disrupts existing relational ecologies comprising human and non-human beings. The thesis concludes by suggesting that the Yaguan adoption of modern technical artefacts parallels their domestication of wild animals
Harder-Narasimhan filtrations of persistence modules
Get PDFMultiparameter persistence modules are central objects in Topological Data Analysis. Unlike ordinary persistence modules, they do not admit a complete discrete invariant such as the barcode. This thesis explores the use of Harder-Narasimhan theory as a way to devise discrete invariants of multiparameter persistence modules that are discriminating, computable, stable and interpretable.Harder-Narasimhan types are a family of discrete invariants of persistence modules over finite posets. We first study their discriminating power in several settings arising in Topological Data Analysis. We then use Harder-Narasimhan types to define the skyscraper invariant, a novel discrete invariant of multiparameter persistence modules. We show that this invariant is strictly more discriminating than the rank invariant and is stable with respect to the interleaving distance
Oxidized LDL Induces Pro‐Inflammatory Transcriptomic and Epigenomic Responses in Human CD4 + T Cells
Get PDFElevated circulating low‐density lipoprotein cholesterol (LDL‐C) is a key risk factor for coronary artery disease (CAD). The pathogenesis of CAD is multifactorial, driven by heritable and lifestyle‐related risk factors. Although CD4+ T cells are one of the main cell types in atherosclerotic lesions, their interaction with atherogenic oxidized LDL (ox‐LDL) remains poorly understood. Therefore, we sought to characterize the transcriptomic and epigenomic consequences of ox‐LDL on activated human CD4+ T cells. We find that ox‐LDL causes a shift towards a pro‐inflammatory, cytokine‐producing CD4+ T cell transcriptomic state. Concurrently, ox‐LDL induces genome‐wide changes in chromatin accessibility, notably in promoter regions. By integrating our multiomic data, we identify the NRF1 and SP1 transcription factors as likely mediators of ox‐LDL‐induced changes in gene expression. In contrast, the influence of AP‐1 related factors over CD4+ T cell gene expression decreases following ox‐LDL stimulation. We leveraged our multiomic data to investigate the disease relevance of ox‐LDL exposure, by investigating genomic locations where CAD‐associated single nucleotide polymorphisms were found within dynamic ox‐LDL‐regulated accessible chromatin regions. Together, we demonstrate a disease‐relevant role for ox‐LDL in atherogenic conditioning of CD4+ T cells. Understanding such cell‐type specific interactions with CAD risk factors may facilitate the development of targeted therapies for CAD
Investigating the asymmetric electrochemical, structural and electronic properties of Mn-rich Li(Mn,Fe)PO 4 electrode materials
Get PDFOlivine-type phosphates LiMnxFe1−xPO4 are attracting increasing interest as positive electrode materials for lithium-ion batteries due to their low cost and good electrochemical performance. However, the effects of the mixed Mn/Fe composition on lithium intercalation and ion transport are not fully characterised, especially in Mn-rich compositions. In this study, the electrochemical, structural and ion transport properties of Mn-rich LiMnxFe1−xPO4 (x = 0.6, 0.7, 0.8) (LMFP) are investigated using a combination of experimental and materials modelling techniques. Considerable asymmetry in charge/discharge profiles is found, which highlights the complexity of the mixed-metal system. An intricate lithium intercalation mechanism is observed, including both solid solution and two-phase regions. While the Fe/Mn cation disorder causes the oxidation to proceed mostly via a solid solution mechanism, the Mn plateau remains associated with a two-phase process. Ab initio simulations indicate that Li+ diffusion occurs along one-dimensional channels parallel to the crystallographic b-axis following a curved trajectory, and find favourable Li/Fe and Li/Mn anti-site defect formation. Analysing the band gaps of the lithiated and delithiated phases revealed that Mn substitution of Fe can improve the electronic conductivity, suggesting asymmetric electronic behaviour