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Multi-frequency channel measurements and modeling for RIS-assisted MIMO communications
No full textReconfigurable intelligent surface (RIS)-enabled systems have been widely considered as one of the revolutionary technologies for the new generation of communications. In particular, RIS-assisted multiple-input multiple-output (MIMO) communications have come at the forefront of research, yet there is still lack of supportive channel measurements and modeling in real environments. Against this background, this paper conducts multi-frequency and multi-scenario channel measurements and channel modeling for RIS-assisted MIMO communication systems. Utilizing a temporal autocorrelation-based channel sounder and the fabricated RISs, the virtual RIS-assisted MIMO channels are realized by successively moving the transceiver antennas on movable rotary tables. The channel realizations are collected in indoor hotspot (InH) and urban microcellular (UMi) scenarios at sub-6 GHz and millimeter-wave (mmWave) frequency bands, respectively, where various communication states, different coding schemes of the RIS, as well as with and without RIS deployment are fully considered. Based on the measured channel realizations, critical channel metrics including the signal power, effective rank, spectral efficiency (SE), root-mean-square delay-spread (RMS DS), Ricean K-factor (KF), spatial correlation, etc., are illustrated and compared under different coding schemes, communication states, deployment scenarios, and frequency bands. The measurement results indicate that the coding scheme of the RIS significantly impacts the channel performance, while the capability of RIS to customize the channel is strongly related to the power intensity it provides. Deploying an RIS with energy-focused coding can provide significant signal power gains for non-line-of-sight (NLoS) links and spatial multiplexing gains for line-of-sight (LoS) and obstructed-line-of-sight (OLoS) links, thereby greatly improving the SE. Moreover, it is found that under different communication states, such as RIS-assisted NLoS/LoS/OLoS links, the influence imposed by RIS on the channel metrics could be completely opposite, especially for the KF, RMS DS, and effective rank. In addition, after the RIS deployment with a beamforming mode, the spatial correlation in the NLoS and LoS MIMO channels significantly increases and decreases, respectively. Furthermore, it is verified that the Weichselberger model can provide a satisfactory prediction accuracy on the SE of RIS-assisted MIMO channels, while the Kronecker model underestimates it
Constraints on the progenitor and explosion of SN 2024ggi in harmony with preexplosion detection and hydrodynamic simulations
No full textSupernova (SN) 2024ggi is a nearby Type II SN discovered by the Asteroid Terrestrial-impact Last Alert System, showing early flash-ionization features. The preexplosion images reveal a red supergiant progenitor with an initial mass of 10–17 M⊙. In the present work, we perform detailed hydrodynamic modeling to refine and put robust constraints on the progenitor and explosion parameters of SN 2024ggi. Among the progenitor models in our study, the pre-SN properties of the 11 M⊙ match the preexplosion-detected progenitor well. However, we find it difficult to completely rule out the 10 and 12 M⊙ models. Thus, we provide a constraint of 11 −1+1 M⊙ on the initial mass of the progenitor. To match the observed bolometric light curve and velocity evolution of SN 2024ggi, the favored model with an initial mass of 11 M⊙has a pre-SN radius of 800 R⊙. This model requires an explosion energy of [0.7–0.8] × 1051 erg, nickel mass of 0.049 M⊙, ejecta mass of 9.1 M⊙, and an amount of ∼ 0.5 M⊙ of steady-wind circumstellar medium (CSM) extended up to ∼1.2 × 1014 cm resulting from an eruptive mass-loss rate of 1.0 M⊙ yr−1. We also incorporate the accelerated-wind CSM scenario, which suggests a mass-loss rate of 1.0 × 10−2 M⊙ yr−1 and a CSM mass of ∼0.7 M⊙extended up to ∼1.1 × 1014 cm. This mass-loss rate falls within the range constrained observationally. Additionally, due to the constraint of 11 −1+1 M⊙ on the initial mass, the range of pre-SN radius and ejecta mass would be [690–900] R⊙ and [8.2–9.6] M⊙, respectively
Towards a theory of change to guide a new politics and economics: the need to reclaim politics from growth and vested interests, in part through a shared vision of equity, democracy and ecological limits
No full textOur governments have, for decades, failed to address the housing crisis, crisis of inequality, climate and nature crisis and the wider cultural malaise. Changing which party is in power does not seem enough to address this. Some say this is because our politics is ‘broken’, but what if it is just doing exactly what it is intended to do, for those it serves?Simply doing our best may not be good enough. Our politics and campaigning should be informed be sufficient strategies, or ‘ theories of change’ . That is plans that can reset politics and economics such that it is able to deal with the crises of inequality and lack participation at the very same time as curbing our overproduction and overconsumption that risks both political and planetary breakdown.Recognising and then closing the gap between our mounting inequality and worsening planetary crises requires us to extract our society from the current dominant economic worldviews and the way this works with (liberal/representative) democracy to block this from happening. Bringing about sufficient change must include rethinking politics and releasing it from the grip of growthist economics. A completely different worldview is required to inspire and be brought forward by hope-fuelled political activism. This is explored through the two linked parts of this paper. The first part explores why the current democratic political system is insufficient to address the crises that we face, let alone realise the multiple benefits possible from doing so realistically and democratically.The second part explores why a completely different way to frame ‘climate justice’ is needed for our economic system. We will not secure a decent quality of life for all within climate and nature limits unless that is what we prioritise. Sufficient climate action is not possible without addressing growing inequality – and that in turn is not possible without sufficient climate action.We do not make these points lightly but honestly, based on our realistic assessment of our predicament and how we might best respond in ways that increase democracy, justice and freedom
Long-term low-dose aspirin promotes laser-induced choroidal neovascularization through suppressing TSP-1 expression
No full textPurpose: To investigate the impact of low-dose, long-term aspirin use on neovascular age-related macular degeneration (nAMD).Methods: Adult C57BL/6J or Thbs-1–/– mice were treated with daily aspirin (1.25 mg/kg) for 8 weeks before being subjected to laser-induced choroidal neovascularization (CNV). The animals were left for 7–10 days with continued aspirin use before the eyes were collected for further investigations. Bone marrow-derived macrophages (BMDMs) and primary retinal pigment epithelial (RPE) cells were treated with different concentrations of aspirin (1, 10, 100 μM) for two days before being subjected to LPS+IFNγ for 16 h. The expression of cytokine genes was evaluated by qRT-PCR. The concentrations of thrombospondin-1 (TSP-1) were measured by ELISA.Results: Aspirin treatment did not affect circulating immune cell profiles in normal mice but significantly increased CD11b+ cells in laser-induced CNV mice. The treatment significantly increased the severity of laser-induced CNV and reduced serum levels of TSP-1. In vitro aspirin treatment upregulated Tnfa and Ccl22, down-regulated Thbs-1 mRNA expression, and reduced TSP-1 production in LPS+IFNγ-treated M1 BMDMs but not RPE cells. Thbs-1–/– mice developed severe laser-induced CNV, which was not affected by aspirin intervention. nAMD patients had significantly lower serum levels of TSP-1 than healthy controls, although no significant difference was found between nAMD patients with and without aspirin use.Conclusion: Low-dose long-term aspirin use promoted the severity of laser-induced CNV by down-regulating TSP-1. Lower serum levels of TSP-1 may be a risk factor for nAMD. The long-term ocular safety of aspirin should be validated in prospective cohorts.<br/
ATLAS photometry of interstellar object 3I/ATLAS
No full textWe present calibrated Asteroid Terrestrial-impact Last Alert System (ATLAS) photometry of the interstellar comet 3I/ATLAS (C/2025 N1) from March 28 through 2025 August 29, obtained with the five-site, robotic ATLAS network in the c (420–650 nm), o (560–820 nm), and Teide w (420–720 nm) bands. Stacked difference images yield reliable light curves measured in four fixed apertures that capture the evolving coma. We observe 3I/ATLAS transitioning in color from red (c − o) ≈ 0.7 before MJD 60860 to near-solar (c − o) ≈ 0.3 after MJD 60870, coincident with the appearance of a prominent antisolar tail. The absolute magnitude curve H(t) shows a slope break near MJD 60890 at r ∼ 3.3 au from −0.035 to −0.012 mag day−1, or in terms of coma cross section as a function of heliocentric distance, r−3.9 to r−1.1. We release the aperture photometry with geometry and uncertainties to enable cross-instrument synthesis of 3I/ATLAS activity and color evolution
Consideration of oral health within guidelines and policy documents focused on nutritional status and dietary intake for older adults in care homes in the UK: a scoping review
No full textIntroductionOlder care home residents are particularly vulnerable to both malnutrition and chronic dental diseases, such as caries and periodontal disease. While high-sugar oral nutritional supplements and fortified foods are commonly used to prevent undernutrition, excessive sugar intake increases the risk of dental caries. Despite the well-established interplay between nutrition and oral health, existing guidelines and policy documents tend to address these aspects separately, resulting in fragmented care. This study aims to examine how oral health is considered within guidelines and policy documents focused on nutritional status and dietary intake for care home residents in the United Kingdom.MethodsA scoping review was conducted using Arksey and O'Malley's framework. A systematic search identified UK and Irish based guidelines and policy documents addressing both nutrition and oral health in care homes. Documents exclusively covering either nutrition or oral health were excluded. Data were extracted, reviewed and analysed thematically.ResultsTwelve documents were included: five nutritional documents incorporating oral health and seven oral health documents referencing dietary intake. Nutritional documents acknowledged sugar-related oral health risks but lacked practical caries prevention strategies. Oral health documents emphasised sugar restriction and hygiene but provided limited guidance on balancing nutritional adequacy with oral health preservation.ConclusionCurrent guidelines and policy documents insufficiently integrate oral health and nutrition, resulting in fragmented care. Future policies should adopt an interdisciplinary approach, incorporating evidence-based dietary and oral health strategies to improve care home residents' well-being.<br/
Textual interpretation of transient image classifications from large language models
No full textModern astronomical surveys deliver immense volumes of transient detections, yet distinguishing real astrophysical signals (for example, explosive events) from bogus imaging artefacts remains a challenge. Convolutional neural networks are effectively used for real versus bogus classification; however, their reliance on opaque latent representations hinders interpretability. Here we show that large language models (LLMs) can approach the performance level of a convolutional neural network on three optical transient survey datasets (Pan-STARRS, MeerLICHT and ATLAS) while simultaneously producing direct, human-readable descriptions for every candidate. Using only 15 examples and concise instructions, Google's LLM, Gemini, achieves a 93% average accuracy across datasets that span a range of resolution and pixel scales. We also show that a second LLM can assess the coherence of the output of the first model, enabling iterative refinement by identifying problematic cases. This framework allows users to define the desired classification behaviour through natural language and examples, bypassing traditional training pipelines. Furthermore, by generating textual descriptions of observed features, LLMs enable users to query classifications as if navigating an annotated catalogue, rather than deciphering abstract latent spaces. As next-generation telescopes and surveys further increase the amount of data available, LLM-based classification could help bridge the gap between automated detection and transparent, human-level understanding
Antitumor activity of death receptor 5-targeted camptothecin-loaded nanoparticles in murine syngeneic models
No full textDeath receptor 5 (DR5) is a key mediator of the extrinsic apoptotic pathway that is often upregulated in tumors, rendering it an attractive target for cancer therapy. Activation of DR5 requires oligomerization, which can be achieved through multivalent presentation of DR5 ligands on nanoparticles. DR5-targeted nanoparticles can efficiently agonize DR5 to inhibit the growth of human xenografts, although it remains unclear whether these effects would translate to a syngeneic tumor model with an immunocompetent microenvironment. Here, we develop camptothecin-loaded polymeric nanoparticles coated with the murine DR5 antibody MD5–1 and demonstrate their pro-apoptotic effects in murine cell lines in vitro. Moreover, we show that these nanoparticles inhibit the growth of MC38 colorectal allografts in vivo by >90% relative to control nanoparticles. Collectively, our work confirms that the antitumor efficacy of DR5-targeted nanoparticles extends to syngeneic models, paving the way for future studies to explore their impact on tumor immunity and the surrounding microenvironment.<br/
EMTReK model for advance care planning in long-term care: qualitative findings from mySupport Study
No full textBackground/Objectives: Conversations about end-of-life care or advance care planning are often difficult and emotionally challenging to initiate. Tailoring messages to the specific audiences can make these sensitive discussions more manageable and effective. The Evidence-based Model for the Transfer and Exchange of Research Knowledge (EMTReK), compromising six core components (message, stakeholders, processes, context, facilitation, and evaluation) offers a structured framework for research dissemination and knowledge transfer in palliative and long-term care settings. Knowledge translation bridges research and practice, with its effectiveness depending on stakeholder engagement, tailored communication, and systematic application of evidence in policy and practice. This study explores stakeholder perspectives on a dementia care intervention, using EMTReK as an analytical framework to examine how knowledge transfer and exchange (KTE) actions were implemented across long-term care settings. Methods: A qualitative analysis was conducted on primary data comprising case narratives from multinational research groups involved in the “Caregiver Decision Support” (mySupport) study (2019–2023). Teams from Canada, the Czech Republic, Ireland, Italy, the Netherlands, and the United Kingdom evaluated the mySupport intervention through interviews, with analysis guided by components of the EMTReK model. Results: Facilitated Family Care Conferences were found to be effective mechanisms for supporting knowledge transfer and intervention uptake in dementia care across nursing homes in Europe and Canada. Despite challenges posed by the COVID-19 pandemic, Family Care Conferences adapted through stakeholder engagement, interactive learning, and innovative communication methods. Using EMTReK as an analytical framework, the research team identified key elements that contributed to successful implementation, including the importance of flexibility to accommodate local contexts.Conclusions: The transnational application of the EMTReK model for advance care planning in long-term dementia care highlights the importance of tailored, culturally relevant knowledge translation strategies, which, despite challenges from the COVID-19 pandemic, were successfully implemented through local adaptations and diverse dissemination methods, emphasising the need for further research on their impact on resident and family outcomes