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Politics and power in the global tennis circuit
No full textLike most global sports, professional tennis is eager to claim that politics has no place on its playing field. On closer investigation, however, this ‘myth of autonomy’ soon cracks. In addition to adding tennis as a much-needed case to the study of sport and international affairs, this article develops the concept of ‘the circuit’ to approach phenomena that criss-cross traditional levels of analysis in international relations. In its first part, the article zooms in on the practice of writing celebratory messages onto the lenses of TV cameras as an example of the power relations that exist in and around professional tennis courts today. In its second part, it zooms out to map the themes and questions that have framed tennis as a political activity around the world and over time. The analysis identifies and characterizes the global tennis circuit as a site within which many of the most pressing political questions of our time are contained, focusing on the prestigious tournaments which make up the Grand Slam, and the elite athletes that participate in them.<br/
Planlægning og eksempler på biodiversitet og grøn omstilling – set gennem et udvalg af bøger
No full textLandskabets grønne omstilling og biodiversitet har sat mange tanker i gang i Europa. Et udpluk af bøger, der er udgivet de seneste år, viser nogle tendenser, som også har stor betydning for forholdene i Danmark.Landskabets grønne omstilling og biodiversitet har sat mange tanker i gang i Europa. Et udpluk af bøger, der er udgivet de seneste år, viser nogle tendenser, som også har stor betydning for forholdene i Danmark
Befolkningens syn på naturnationalparker
No full textEt nyt dansk naturforvaltningskoncept – naturnationalparker – vil i følge de eksisterende planer komme til at omfatte knap 15 % af de statsligt ejede skov- og naturarealer. 15 parker er blevet udpeget. En spørgeskema-undersøgelse har sat fokus på befolkningens syn på naturnationalparkerne.Et nyt dansk naturforvaltningskoncept – naturnationalparker – vil i følge de eksisterende planer komme til at omfatte knap 15 % af de statsligt ejede skov- og naturarealer. 15 parker er blevet udpeget. En spørgeskema-undersøgelse har sat fokus på befolkningens syn på naturnationalparkerne
Optimizing cleaning strategies for biofouling in reverse osmosis membrane systems:A comparative study using a self-formed instrument
No full textMembrane biofouling poses a serious challenge in reverse osmosis (RO) plants used for water recovery, which cannot be addressed by traditional chlorine-based cleaning agents. To accommodate this problem and enhance membrane performance while maintaining high-quality water production, various cleaning strategies have been applied. It remains however challenging to identify optimal cleaning agents, as tests require discontinuation of production to evaluate the effect. This study introduces a self-formed instrument that mimics industrial RO plants on a small scale to compare the cleaning agents in a fast, affordable and feasible approach. The setup was demonstrated using three cells operating in parallel and a thorough comparison of these. Specifically, the online cleaning efficiency of a typical biofouling cleaner, a solution of NaOH/sodium dodecyl sulfate (SDS), and the commonly used non-oxidizing biocide, 2,2-dibromo-3-nitrilopropionamide, were compared to validate the system performance when fed with membrane bioreactor effluent. The effectiveness of the cleaning process was evaluated using a combination of hydrodynamic operation and membrane autopsy to estimate the biofoulant amount and composition. During a 7-day operating period, it was observed that treated membranes demonstrated higher flux rates compared to untreated membranes. The normalized flux increased more than double in the membrane after it had been cleaned with NaOH/SDS solution. CLSM analysis clearly showed the distinct effects of the two cleaning solutions on the amount and spatial structure of the biofilm layer. Cleaning with DBNPA was able to reduce the load of living bacteria, but not necessarily remove the biofilm components completely. Comparative analyses of membranes revealed that NaOH/SDS exhibited the highest cleaning efficiency during the online cleaning operation mode. This benchmark highlights the versatility of the system, which can be assembled at relevant sites and assist in the identification of efficient and eco-friendly agents that promote the lifespan of membranes. With the distribution of this instrument, it will be possible to accelerate the investigation of multiple cleaning strategies and also analyze interactions among cleaning agents in an attempt to reduce water shortage.</p
Inelastic neutron scattering study of the magnetic field dependence of the quantum dipolar garnet Yb<sub>3</sub>Ga<sub>5</sub>O<sub>12</sub>
No full textDynamical Lensing Tomography of Black Hole Ringdowns
No full textStrong gravitational lensing occurs when photons pass through the vicinity of a black hole. We investigate this phenomenon in the context of a gravitational-wave event, specifically when a black hole is settling into its final state. The deflection angle of photons mimics the ringdown pattern of the gravitational wave at intermediate times. At late times it has an inverse cubic dependence on observation time. The deviation angle increases exponentially as photons approach the photon ring orbit, reflecting its unstable nature. Our findings are directly applicable to imaging scenarios involving stars against the background of compact binaries or circumbinary accretion disks, particularly during the merger of two black holes.</p
Probing Hilbert space fragmentation with strongly interacting Rydberg atoms
No full textHilbert space fragmentation provides a mechanism to break ergodicity in closed many-body systems. Here, we propose a feasible scheme to explore this exotic paradigm on a Rydberg quantum simulator. We show that the Rydberg Ising model in the large detuning regime can be mapped to a generalized folded XXZ model featuring a strongly fragmented Hilbert space. The emergent Hamiltonian, however, displays distinct timescales for the transport of a magnon and a hole excitation. This interesting property facilitates a continuous tuning of the Krylov-subspace ergodicity, from the integrable regime, to the Krylov-restricted thermal phase, and eventually to the statistical bubble localization region. By further introducing nonlocal interactions, we find that both the fragmentation behavior and the ergodicity of the Krylov subspace can be significantly enriched. We also examine the role of atomic position disorders, and we identify a symmetry-selective many-body localization transition. We demonstrate that these phenomena manifest themselves in quench dynamics, which can be readily probed in state-of-the-art Rydberg array setups.</p
