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Abstract The emerging fluid antenna technology enables a high‐density position‐switchable antenna in a small space to obtain enormous performance gains for wireless communications. To understand the theoretical performance of fluid antenna systems, it is important to account for the strong spatial correlation over the different positions (referred to as ‘ports'). Previous works used a classical, generalised correlation model to characterise the channel correlation among the ports but were limited by the lack of degree of freedom of the model to imitate the correlation structures in an actual antenna. In this letter, it is proposed to use a common correlation parameter and to choose it by setting the correlation coefficient of any two ports to be the same as the average correlation coefficient of an actual fluid antenna taking up a linear space. A closed‐form expression for the spatial correlation parameter is first derived assuming that the number of ports is large, and it is illustrated that the correlation parameter depends only on the size of the fluid antenna but not the port density. Simpler expressions are then obtained for small and large sizes of fluid antenna. The resulting model is finally used to study the performance of fluid antenna systems. Simulation results based on the proposed model are provided to confirm the promising performance of fluid antenna in single and multiuser environments.

Societal Impact Statement Seagrass meadows are a globally important habitat subject to significant loss. As efforts to restore these sensitive habitats are hampered by their high cost and low levels of reliability, rigorous guidance is required to improve effectiveness and ensure they are cost‐effective. Here, we define 10 golden rules for how we can undertake seagrass restoration. We do this by considering that for seagrass restoration to be successful, it needs to take place with people and not against people. The framework we present aims to direct efforts for seagrass restoration that are holistic and achieve broad goals for people, biodiversity and the planet. Summary The world has lost a significant proportion of its seagrass, and although glimmers of hope for its recovery exist, losses and degradations continue. First and foremost, evidence highlights the need to put the world on a global pathway to seagrass net gain. Achieving this outcome requires that conservation of what remains is a priority, but reaching net gain requires seagrass coverage to increase at rates unlikely to be achieved naturally; large‐scale active restoration is required to fill this gap. Novel finance mechanisms aligned to the climate emergency and biodiversity crises are increasingly leading to larger scale restoration projects. However, no clear framework exists for developing or prioritising approaches. With seagrass restoration expensive and unreliable, rigorous guidance is required to improve effectiveness and ensure it is cost‐effective. Building on evidence from terrestrial and marine sources, here, we apply the ‘10 golden rules’ concept, first outlined for reforestation and later applied to coral reefs, to seagrass restoration. In doing so, we follow international standards for ecological restoration and view seagrass restoration in a broad context, whereby regeneration can be achieved either by planting or by enhancing and facilitating natural recovery. These rules somewhat differ from those on reforestation and coral reef restoration, principally due to the relative immaturity of seagrass restoration science. These 10 golden rules for seagrass restoration are placed within a coupled social‐ecological systems context, and we present a framework for conservation more broadly, to achieve multiple goals pertaining to people, biodiversity and the planet.

Abstract The lack of accurate information on the spatiotemporal variations of snow water equivalent (SWE) in mountain catchments remains a key problem in snow hydrology and water resources management. This is partly because there is no sensor to measure SWE beyond local scale. At Mt. Zugspitze, Germany, a superconducting gravimeter senses the gravity effect of the seasonal snow, reflecting the temporal evolution of SWE in a few kilometers scale radius. We used this new observation to evaluate two configurations of the Alpine3D distributed snow model. In the default run, the model was forced with meteorological station data. In the second run, we applied precipitation correction based on an 8 m resolution snow depth image derived from satellite observations (Pléiades). The snow depth image strongly improved the simulation of the snowpack gravity effect during the melt season. This result suggests that satellite observations can enhance SWE analyses in mountains with limited infrastructure.

Societal Impact Statement Seagrass ecosystems are of fundamental importance to our planet and wellbeing. Seagrasses are marine flowering plants, which engineer ecosystems that provide a multitude of ecosystem services, for example, blue foods and carbon sequestration. Seagrass ecosystems have largely been degraded across much of their global range. There is now increasing interest in the conservation and restoration of these systems, particularly in the context of the climate emergency and the biodiversity crisis. The collation of 100 questions from experts across Europe could, if answered, improve our ability to conserve and restore these systems by facilitating a fundamental shift in the success of such work. Summary Seagrass meadows provide numerous ecosystem services including biodiversity, coastal protection, and carbon sequestration. In Europe, seagrasses can be found in shallow sheltered waters along coastlines, in estuaries & lagoons, and around islands, but their distribution has declined. Factors such as poor water quality, coastal modification, mechanical damage, overfishing, land‐sea interactions, climate change and disease have reduced the coverage of Europe’s seagrasses necessitating their recovery. Research, monitoring and conservation efforts on seagrass ecosystems in Europe are mostly uncoordinated and biased towards certain species and regions, resulting in inadequate delivery of critical information for their management. Here, we aim to identify the 100 priority questions, that if addressed would strongly advance seagrass monitoring, research and conservation in Europe. Using a Delphi method, researchers, practitioners, and policymakers with seagrass experience from across Europe and with diverse seagrass expertise participated in the process that involved the formulation of research questions, a voting process and an online workshop to identify the final list of the 100 questions. The final list of questions covers areas across nine themes: Biodiversity & Ecology; Ecosystem services; Blue carbon; Fishery support; Drivers, Threats, Resilience & Response; Monitoring & Assessment; Conservation & Restoration; Governance, Policy & Management; and Communication. Answering these questions will fill current knowledge gaps and place European seagrass onto a positive trajectory of recovery.

Abstract Leveraging the potential of virtual platforms in the post‐COVID‐19 era, the Infection and Pulmonary Vascular Diseases Consortium (iPVDc), with the support of the Pulmonary Vascular Research Institute (PVRI), launched a globally accessible educational program to highlight top‐notch research on inflammation and infectious diseases affecting the lung vasculature. This innovative virtual series has already successfully brought together distinguished investigators across five continents – Asia, Europe, South and North America, and Africa. Moreover, these open global forums have contributed to a comprehensive understanding of the complex interplay among immunology, inflammation, infection, and cardiopulmonary health, especially concerning pulmonary hypertension and related pulmonary disorders. These enlightening discussions have not only heightened awareness about the impact of various pathogenic microorganisms, including fungi, parasites, and viruses, on the onset and development of pulmonary vascular diseases but have also cast a spotlight on co‐infections and neglected illnesses like schistosomiasis ‐ a disease that continues to impose a heavy socioeconomic burden in numerous regions worldwide. Thus, the overall goal of this review article is to present the most recent breakthroughs from infectious PVDs as well as bring to light the scientific and educational insights from the 2023 iPVDc/PVRI virtual symposium series, shaping our understanding of these crucial health issues in this more than ever interconnected world.

Abstract Nickel stable isotopes (δ60Ni) provide insight to Ni biogeochemistry in the modern and past oceans. Here, we present the first Pacific Ocean high‐resolution dissolved Ni concentration and δ60Ni data, from the US GEOTRACES GP15 cruise. As in other ocean basins, increases in δ60Ni toward the surface ocean are observed across the entire transect, reflecting preferential biological uptake of light Ni isotopes, however the observed magnitude of fractionation is larger in the tropical Pacific than the North Pacific Subtropical Gyre. Such surface ocean fractionation by phytoplankton should accumulate isotopically lighter Ni in the deep Pacific, yet we find that North Pacific deep ocean δ60Ni is similar to previously reported values from the deep Atlantic. Finally, we find that seawater dissolved δ60Ni in regions with hydrothermal input can be either higher or lower than background deep ocean δ60Ni, depending on vent geochemistry and proximity.

Abstract Objective We aim to evaluate the safety and effectiveness of radiofrequency ablation (RFA) for benign thyroid nodules by ENT surgeons and to compare it to conventional hemithyroidectomy in the public healthcare, operating theater contained setting. Methods 50 patients who underwent a single session of RFA for symptomatic benign thyroid nodules in Prince of Wales Hospital and Tseung Kwan O Hospital in Hong Kong from 2020 to 2022 were evaluated. Objective outcomes including nodule volume, volume reduction rate (VRR) and complications were recorded. Subjective response in the form of a 0–10 point scale for patient symptoms including obstructive, cosmetic, pain and satisfaction scores were collected. Results Significant reduction in mean VRR was found at 3, 6 and 12 months post treatment, accompanied by a significant reduction in the mean obstructive and cosmetic symptom scores. Comparing with conventional hemithyroidectomy, the RFA group had a significantly shorter mean procedure time and lower rate of complications. Estimated cost to patient for RFA was found to be less than half of that of hemithyroidectomy. Conclusion RFA is a safe and effective treatment modality for benign thyroid nodules by ENT surgeons with advantages of being a scarless local anesthetic procedure with shorter procedure time, lower complication rate and lower cost to patient compared to hemithyroidectomy. In Hong Kong, where most of the population is treated in the public sector, there are limited resources, often with high caseload burden and long operation waiting times. Therefore, RFA is an office‐based treatment that serves as a valuable alternative to hemithyroidectomy for benign nodules, especially in lower resource settings. Level of evidence 3.

Bacterial biofilms are widely found in nature, and they can be a major factor in many local chronic infections inside the human body. To date, effective elimination of biofilms is intractable for conventional antibiotic therapies due to the existence of bacteria‐protecting extracellular polymeric substances. For biofilm eradication in tiny tubular structures, magnetic hydrogel micromachines (MHM) are designed that are capable of performing mechanical disruption of biofilms while releasing antibacterial agents in a controllable fashion. Two modes of motion controlled by external magnetic fields, namely planar rotation and wobbling modes, have been investigated to drive the micromachines to interact and destruct biofilms. In addition, the presented micromachines are composed of thermosensitive PNIPAm hydrogel that can load with the antibacterial agent (H2O2) and release them upon heating. The Fe3O4 nanoparticles embedded in the hydrogel matrix act as catalysts for the Fenton reaction, generating bacteria‐killing free radicals. The synergetic biofilm elimination effect has been experimentally demonstrated in well plates and small tubes. The presented MHMs may provide a new design to treat biofilm‐related infections in narrow and confined spaces.

Abstract Background and Aims This study aims to describe inequalities in health indicators according to gender, area of residence, and socioeconomic position among Brazilian adolescents. Methods Cross‐sectional study using data from a school‐based survey carried out in Brazil in 2019. Twelve health outcomes were evaluated. Dimensions of inequality assessed were gender, area of residence, wealth and subnational region. Results This study comprises a sample of 124,898 adolescents. The most prevalent outcome was physical inactivity (71.9%) followed by thinking life is worthless (52.6%) and bullying (51.8%). Gender inequalities were more marked for physical inactivity and thinking life is worthless with girls presenting a prevalence more than 20 p.p. higher than boys. In zero‐dose HPV, however, the prevalence in girls was 17.7 p.p. lower than in boys. Area of residence and wealth inequalities were smaller than gender disparities. Context presented a relevant role in inequality with analysis stratified by states of the country, revealing high variability in estimates. Conclusions We highlight the need for attention to disparities between subgroups of the adolescent population, especially for gender inequalities that were the most marked for this age group.