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Red-shifted circularly polarised luminescence from helically chiral N,N,O,O-boron chelated dipyrromethenes through synthetically facile meso-CF3 modification
Get PDFIn the search for red-shifted small molecule emitters of circularly polarized light, a helically chiral N,N,O,O-boron chelated dipyrromethene (BODIPY) is described containing a meso-CF3 group, prepared in only two synthetic steps. The incorporation of an electron deficient substituent at the meso-position of a helically chiral BODIPY results in significant (∼50 nm) red-shift of both the absorption (615 → 669 nm) and emission maxima (635 → 686 nm) in comparison to the parent compound, whilst maintaining a high extinction coefficient (83,000 mol−1 cm−1) and reasonable fluorescence quantum yield (0.30). Enantiomers were resolved by chiral stationary phase HPLC and absolute configuration assigned by the comparison of the experimental and calculated ECD spectra (∣gabs∣ = 3.6 × 10−3). A luminescence dissymmetry factor (∣glum∣ = 2.3 × 10−3) is reported, well supported by calculation (∣glum(calc)∣ = 2 × 10−3), resulting in an overall CPL brightness (BCPL = 29 M−1 cm−1) that is consummate with similar helically chiral monomeric BODIPYs. This work demonstrates the use electron deficient meso-CF3 groups in the development of red-shifted circularly polarised luminescent small organic molecules (CPL-SOMs), whilst maintaining their key chiroptical properties
Thermal response of heterolithic deposits in flooded coal mines: implication for heat storage potential
Get PDFHeat transfer rates are critical to underground heat storage recovery potential and sustainability of thermal abstraction for heating and cooling buildings. A 17-day heat injection – abstraction experiment into a flooded, disused mine working was conducted at the UK Geoenergy Observatory in Glasgow. Analysis of the thermal response of different lithologies intersected by an injection borehole during and after a heat injection experiment is used to quantify the heat exchange between rock mass and circulating mine water. The monitoring data from Distributed Temperature Sensing (DTS) has been analysed and numerical models using COMSOL Multiphysics were developed to characterise the rates and controls on thermal processes during heat injection and recovery. The results suggest the key control of the borehole construction on the temperature change in the first 10 hour of heat injection. In the long term, the thermal response mainly depends on the thermal conductivity of the lithologies. The radial heat transfer reaches a steady charging rate of 23 W/m2 and 16 W/m2 in the sandstone and clay intervals, respectively, and a maximum of 14 W/m2 and 10 W/m2 at the start of recovery. This is accompanied by upward heat diffusion/convection from the mine working. This study demonstrates the ability of DTS to identify lithological heterogeneities at a high resolution, and the importance of considering the overburden structure and lithology for thermal storage applications
Structure and Dynamics of the Deprotonated Demethoxycurcumin and Bisdemethoxycurcumin Anions
Get PDFThe curcuminoids are polyphenols found in the spice turmeric, where its principal polyphenol, curcumin, has been attributed with many of turmeric’s beneficial therapeutic properties. However, as curcumin has a low bioavailability, other curcuminoids, which have fewer terminal methoxy substituents and have been reported to have a higher bioavailability, have been investigated as possible therapeutics. In this article, we report the results of the first gas-phase ion spectroscopy study of the deprotonated anionic forms of two prevalent curcuminoids: demethoxycurcumin and bisdemethoxycurcumin. The results indicate that the deprotonated curcuminoid anions have an electronic structure very similar to that of the deprotonated curcumin anion, with one bound electronically excited state and two low-lying anion resonances. Furthermore, all of the deprotonated curcuminoid anions have similar adiabatic detachment energies and show clear evidence of internal conversion following photoexcitation. Therefore, the curcuminoids studied here may be expected to perform a similar biological and/or therapeutic role to curcumin, given their similar electronic structure and energy transfer dynamics
Generalised Fisher Information in Defective Fokker-Planck Equations
Get PDFThe goal of this work is to introduce and investigate a generalised Fisher Information in the setting of linear Fokker-Planck equations. This functional, which depends on two functions instead of one, exhibits the same decay behaviour as the standard Fisher information, and allows us to investigate different parts of the Fokker-Planck solution via an appropriate decomposition. Focusing almost exclusively on Fokker-Planck equations with constant drift and diffusion matrices, we will use a modification of the well established Bakry-Emery method with this newly defined functional to provide an alternative proof to the sharp long time behaviour of relative entropies of solutions to such equations when the diffusion matrix is positive definite and the drift matrix is defective. This novel approach is different to previous techniques and relies on minimal spectral information on the Fokker-Planck operator, unlike the one presented in [6] where powerful tools from spectral theory were needed
Mediatization: Adopting Media Logics in Arts Marketing
Get PDFThis chapter examines how media logics have been adopted in arts marketing. We argue that marketing practices in what have historically been called ‘the arts’ have borrowed and adapted media logics from popular culture, leading to a mediatization of the arts and the breaking down of boundaries between what were once called arts, popular culture, and craft. We begin with an overview of how the relationship between the arts, the market, and marketing has developed throughout recent history. This is then followed by a reflection on new ways of thinking about arts marketing, inclusive of a wide range of art forms, both existing and those emerging from the proliferation of new media. To illustrate these points, we conclude the chapter with a case study of the ShantyTok phenomenon on TikTok, which Scottish musician Nathan Evans’ ignited with his acapella rendition of the old New Zealand whaling song, “Soon May the Wellerman Come”
A novel analytical formulation for obtaining solitary wave solutions with a focus on gravity-driven liquid films
Get PDFA potential-based, first-integral formulation of the Navier–Stokes equations is used as the platform for modelling solitary waves in the context of gravity-driven film flow on planar surfaces, resulting in a nonlinear partial differential equation (PDE), in complex form. Its subsequent modal decomposition, leading to an infinite set of ordinary differential equations (ODEs), followed by a bimodal approximation and elimination of unknowns, results in just two coupled ODEs to be solved. The latter is achieved both analytically and numerically using a Ritz–Galerkin methodology. Illustrative solitary wave results are provided, which exhibit the expected internal recirculating flow pattern and the corresponding pronounced hump-shaped, free-surface displacement typically observed in related experiments and consistent with other analytical/numerical results in the literature. Despite the numerous approximations involved in arriving at such a minimalist model, the same is capable of providing valid predictions apropos solitary waves; namely, regarding the existence of multiple solutions for a given film thickness and effective inclination angle, with different size and propagation speed, as demonstrated by the parameter study undertaken. Another remarkable feature is the paired occurrence of solitary wave and anti-wave solutions
Trait procrastination and future time orientation: Multi-sample tests of the stress orientation hypothesis
Get PDFTheory and research characterise habitual procrastination as a temporal trait that is associated with difficulties in mood regulation and future-oriented thinking. Yet the reason why trait procrastination is linked to thinking less about the future have not been fully investigated. Guided by the stress orientation hypothesis, the current study aimed to test the role of stress in the link between procrastination and future time orientation (FTO). Across 11 samples (Total N = 4193) we meta-analysed the unadjusted and adjusted (controlling for the contributions of stress) associations between procrastination and FTO, and tested the influence of demographic, methodological, and conceptual moderators. Consistent with theory, trait procrastination was significantly and negatively associated with FTO and stress, and stress was negatively associated with FTO. When the contribution of perceived stress was accounted for, the pooled effect size was reduced from medium-to-large-sized (r avg = −0.373) to small-tomedium-sized (r avg = −0.224), suggesting an explanatory role for stress. Both sets of effects were influenced by the FTO measure and the proportion of females in the sample. These findings provide robust evidence that the stress associated with chronically procrastinating contributes to difficulties with future-oriented thinking, suggesting that stress management may have benefits for FTO
Modeling, Capacity Studies, Antenna and System Designs for 6G/B6G 3-D Continuous-Space Radio Channels Enabled by Electromagnetic Information Theory
Get PDFChannel theory is a fundamental theory of wireless communications. The sixth generation (6G) and beyond 6G (B6G) wireless communication networks are expected to provide space-air-ground-sea global coverage. Base stations and users tend to move in three dimensional (3D) continuous spaces, while antennas and propagation environments can be tightly coupled. The underlying channels show an evolutionary trend to 3D continuous-space radio channels that combine antennas and wireless propagation channels, in comparison to discrete local-space wireless propagation channels in previous generations. This introduces new challenges for channel modeling, channel capacity analysis, antenna design, system design, etc. To address these challenges, this paper performs a comprehensive study on 3D continuous-space radio channels in 6G/B6G with the aid of electromagnetic information theory (EIT) that integrates electromagnetic theory, information theory, wireless propagation channel modeling theory, and antenna theory. We start by revealing the connections and gaps between these four fundamental theories. Then, an in-depth investigation on the four major research thrusts of 3D continuous-space radio channels is provided: 1) channel measurements and modeling, 2) channel capacity analysis, 3) general antenna design, and 4) wireless system design. We aim to explore the intrinsic relationships between antenna parameters, channel parameters, channel characteristics, channel capacity, and communication system performance. Finally, future research directions and challenges for 3D continuous-space radio channels are outlined. Our study endeavors to establish a fundamental framework for 3D continuous-space radio channels, with the potential to catalyze breakthroughs in 6G/B6G theories
Neurodiversity and the Contemporary in the 21st-Century Novel
No full textOffering a provocative analysis of neurodivergent and twenty-first-century perspectives on time and some of its cultural expressions, this open access book is the first comparative study of the intersections between neurodiversity and the evolving field of Contemporary Studies.Blending literary close reading and sociological discourse analysis, the book turns to fiction for the strategic insights it can offer into cultural imaginaries of neurodiversity and time. With a focus on twenty-first-century novels from authors such as Jonathan Safran Foer, Lisa Genova, John Wray, and Julie Dachez, it interrogates the entanglements between categories of crip time and the contemporary, examines the processes of exclusion governing neurodivergence construction, and advocates for a new vocabulary demonstrating the role of contemporary neuroinclusive perspectives in twenty-first-century epistemological processes
Neither from Within nor from Without: How States Securitize Diasporas
No full textDiasporas and their transnational ties to their homelands and various other networks raise heightened suspicion in their countries of residence. Diasporas are perceived as non-state actors that form transnational and non-transparent ties with their homelands, foster long-distance nationalism, and create potential dual loyalties. Moreover, they are perceived as a potential source of tension due to the possibility of transporting homeland conflicts, leading to public unrest and security issues in the transnational space. Countries of origin often share similar concerns. While harnessing the potential of diasporas has become a trend in the international arena, home states also, at times, perceive diasporas as conflict perpetuators, regime destabilizers or dissidents that need to be tamed and controlled. Both perspectives define diaspora members based on presumed geographic, racial, cultural, ethnic and religious origins; whether they embrace diasporas or treat them as potential threats, they still act to protect the cultural and political unity of the nation-state as we know it. This article explores how diasporas, especially from conflict areas, are constructed as security threats by various actors, while acknowledging a recent trend that celebrates diasporas as agents of peace. It argues that the securitization of diasporas remains prevalent across borders, and these policies serve a vital function for both host and home countries by affirming internal accountability and securing national unity by guarding against external threats to the state
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