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Development and Photophysical Characterization of Bioinspired Materials
No full textPorphyrins are versatile aromatic macrocycles with unique photophysical properties that make them attractive for applications in light harvesting, photocatalysis, and sustainable energy conversion. Incorporating porphyrins into metal-organic frameworks (MOFs) offers a unique opportunity to modulate their photophysical behavior through spatial confinement and host–guest interactions. This thesis explores how structural modifications influence porphyrin excited-state behavior through a multi-stage investigation. The work begins by comparing the photophysical properties of two cationic porphyrins: tetra(N-methylpyridyl) porphyrin(TMPyP) and tetra(4-N,N,N-trimethylanilinium) porphyrin(4TANP). While TMPyP exhibits significant singlet–charge transfer (S₁–CT) state mixing due to charge delocalization onto peripheral pyridinium groups, 4TANP lacks comparable behavior. The localized nature of its anilinium substituents prevents effective CT state formation, as confirmed through steady-state spectroscopy and emission lifetime analysis. Building on these findings, 4TANP was encapsulated into a crystalline metal-organic framework (MOF), MOM-11, to probe the effect of spatial confinement on its photophysics. Structural analysis revealed distorted porphyrin conformations within the MOF cavities, and changes in emission profiles indicated perturbations in excited-state dynamics due to host–guest interactions. To further explore energy and electron transfer in confined systems, a mixed-bed MOF architecture was developed by co-encapsulating a ruthenium complex (RuBpy) as an energy donor and cobalt(III) tetra(4-sulfonatophenyl)porphyrin (Co4SP) as an electron-deficient acceptor within HKUST-1(Zn). Spectroscopic studies demonstrated spectral overlap conducive to Forster resonance energy transfer (FRET), and lifetime measurements showed dynamic quenching of RuBpy upon increasing Co4SP loading. Stern–Volmer analysis supported a reductive photoinduced electron transfer (PET) pathway with cavity-dependent efficiency, while FRET remained active over longer donor–acceptor distances. These findings collectively illustrate the importance of electronic structure, substituent design, and spatial confinement in modulating porphyrin photophysics. This work provides insights into the design of MOF–porphyrin hybrid materials for targeted applications in photocatalysis, molecular electronics, and artificial photosynthesis
Book Review: \u3cem\u3eResearch Handbook on the Punishment of Atrocity Crimes\u3c/em\u3e
No full textChuck Owen Oral History Interview
No full textFive-time Grammy nominated Jazz composer and longtime USF professor Chuck Owen as he reflects on his career building the university’s jazz studies program, working with renowned artists, and leading his ensemble, The Jazz Surge. He shares stories from decades in music, including a concert with Art Blakey halted by Blakey’s wife over a tape recorder and a dramatic studio evacuation during the recording of “Sparks Fly” when sparks were literally arcing on the roof. Owen discusses his band’s unique instrumentation—especially the inclusion of violinist Sara Caswell and two guitarists—and his pride in former students now succeeding across the music industry like Bob Thompson, President of Wise Music Group. He explains his creative process, emphasizing playfulness, reflection, and writing for the individual voices of musicians such as vocalist Kate McGarry. He recalls how his band has become a family and prefers to work with musicians like Andrea Bocelli’s bassist Mark Neuenschwande
Bronze Figure of Young Man
No full textWith his broad shoulders and narrow waist, as well as his neat hairstyle (short in the front, long in the back), this bronze figurine illustrates the influence of Greek sculptural art in Etruria. In Archaic Greece, the kouros (“youth”) reflected the ideal male beauty – nude, noble and athletic. Greek kouros-type sculpture, with its stiff pose – arms along the body, straight legs and left foot stepping slightly forward – was itself inspired by Egyptian artistic tradition. This charming bronze statuette is therefore an example of the interconnectedness of the ancient world.https://digitalcommons.usf.edu/etruscan/1012/thumbnail.jp
The Evolving Landscape of European Security: An Assessment of NATO’s Posture and Deterrence Strategies in Response to the Russia-Ukraine War
No full textThe Russia-Ukraine War has reshaped Europe’s security landscape, leading to NATO’s most significant transformation since the Cold War. This study explores how the conflict has prompted NATO to realign its deterrence and defence strategies in response to Russia’s violations of international norms and changing battlefield dynamics. Employing a qualitative analysis of academic literature, official documents and credible reports, this study argues that NATO has shifted from assurance to a more assertive deterrence approach, enhancing its forward presence, increasing defence spending, and adopting effective new technologies. Key findings reveal important lessons about modern warfare, particularly the roles of artillery, unmanned systems, and air defence. The study also addresses the economic and energy repercussions of the conflict, noting how sanctions have reshaped global energy markets and accelerated European energy diversification. Ultimately, it concludes that NATO’s strategic shift represents a lasting change in European security, regardless of the conflict’s outcome
Vestibule (18 a-b)
No full textThis large rectangular hall’s mosaic decoration depicts both an official and a service function. The design of the central image is intact only in the northeastern part. It is defined by the patchy polychrome emblem of the central area, bordered by a black and a white band with a red profile inside. The scene represents people wearing plant crowns, ceremonial clothes, and hairstyles from the tetrarchic age. They are divided into groups and arranged in rows corresponding to different shades of color. The upper group depicts higher-ranking figures, the middle is the lampadarius (or ceremonial master), and the bottom is almost completely lost. All are slightly turned towards the right side of the scene, where it is assumed that the dominus was represented on horseback.https://digitalcommons.usf.edu/idex_casale/1032/thumbnail.jp