7 research outputs found

    Analysis of analog sampled data circuits

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    Synthesis of novel asymmetrically substituted phthalocyanines

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    Phthalocyanines are among the more promising second generation photosensitizers for photodynamic therapy. Our research group has consistently shown that the more amphiphilic of these compounds display improved biological properties as photosensitizers for photodynamic therapy. However, synthetic approaches towards such asymmetrically substituted amphiphilic phthalocyanines are quite limited. As such, we have examined different methodologies for imparting amphiphilicity to phthalocyanine-based photosensitizers. Boron subphthalocyanines are the lower homologs of phthalocyanines and the reactivity of boron subphthalocyanines allows them to react with 1,3-diiminoisoindolines in a Kobayashi ring expansion reaction to give 3:1 asymmetrically substituted phthalocyanines. While several literature examples demonstrate that this protocol can lead to a mixture of substituted phthalocyanine products, the ring expansion reaction of halogenated boron subphthalocyanines in the current study has proven to proceed smoothly to selectively produce the desired 3:1 asymmetrically substituted products. Fluorinated photosensitizers have been previously demonstrated to have interesting properties for PDT and a series of 3:1 asymmetrically substituted dodecafluorinated phthalocyanines have been synthesized by the Kobayashi ring expansion reaction of (dodecafluorosubphthalocyaninato)boron(III) bromide. The asymmetry in these lipophilic compounds improves the photodynamic efficiency of these photosensitizers compared to previously examined symmetrically substituted fluorinated phthalocyanine derivatives. The chemical versatility of aryl iodides, in particular towards palladium-catalyzed reactions, allows for the controlled addition of novel functionality to 3:1 asymmetrically substituted iodinated phthalocyanines prepared by the Kobayashi ring expansion reaction of iodinated boron subphthalocyanines. Palladium-catalyzed reactions have thus been employed in the preparation of new amphiphilic anionic and cationic water-soluble photosensitizers. These compounds should have interesting properties for photodynamic therapy. Lastly, boron subnaphthalocyanines absorb light at a wavelength around 660-680 nm. Their cone-shaped structure prevents aggregation and may impart amphiphilicity to the molecule depending on the nature of the substituents on the subnaphthalocyanine macrocycle and the axial ligand on the central boron. A series of boron subnaphthalocyanines has been synthesized and this class of photosensitizers has been shown to effectively generate singlet oxygen in an aqueous, biologically relevant environment while undergoing rapid photobleaching

    Addiction in context

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    The dissertation provides a comprehensive exploration of the interplay between social and cultural factors in substance use, specifically focusing on alcohol use disorder (AUD) and cannabis use disorder (CUD). It begins by introducing the concept of social plasticity, which posits that adolescents' susceptibility to AUD is influenced by their heightened sensitivity to their social environment, but this sensitivity increases the potential for recovery in the transition to adulthood.A series of studies delves into how social cues impact alcohol craving and consumption. One study using functional magnetic resonance imaging (fMRI) investigated social alcohol cue reactivity and its relationship to social drinking behavior, revealing increased craving but no significant change in brain activity in response to alcohol cues. Another fMRI study compared social processes in alcohol cue reactivity between adults and adolescents, showing age-related differences in how social attunement affects drinking behavior. Shifting focus to cannabis, this dissertation discusses how cultural factors, including norms, legal policies, and attitudes, influence cannabis use and processes underlying CUD. The research presented examined various facets of cannabis use, including how cannabinoid concentrations in hair correlate with self-reported use, the effects of cannabis and cigarette co-use on brain reactivity, and cross-cultural differences in CUD between Amsterdam and Texas. Furthermore, the evidence for the relationship between cannabis use, CUD, and mood disorders is reviewed, suggesting a bidirectional relationship, with cannabis use potentially preceding the onset of bipolar disorder and contributing to the development and worse prognosis of mood disorders and mood disorders leading to more cannabis use

    Simulating urban soil carbon decomposition using local weather input from a surface model

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    Non peer reviewe

    Proceedings of the 19th Sound and Music Computing Conference

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    Proceedings of the 19th Sound and Music Computing Conference - June 5-12, 2022 - Saint-Étienne (France). https://smc22.grame.f
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