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Joint sensing and covert communications in RIS-NOMA systems
No full textA reconfigurable intelligent surface (RIS)-assisted non-orthogonal multiple access (NOMA) system is investigated, where the transmitter (Alice) is a dual-functional radar-communication (DFRC) base station (BS) that aims to sense the location of a potential warden (Willie), while simultaneously transmitting public and covert signals to the legitimate users, Carol and Bob, respectively. Both cases of known and unknown Willie locations are considered. For the known-location case, assuming perfect channel state information (CSI) at Willie, a covert rate maximization is formulated with the joint optimization of active and passive beamforming, which is solved using successive convex approximation (SCA), penalty method, and semidefinite relaxation (SDR). For the unknown-location case, we propose to estimate Willie’s location via radar sensing and develop a sensing-based imperfect CSI model. In particular, the CSI error uncertainty is bounded by the sensing accuracy, which is characterized by the Cramér-Rao bound (CRB). Subsequently, a robust communication rate maximization problem is formulated under the constraints on quality-of-service (QoS) of Carol, sensing accuracy, and covertness level. The Schur complement and S-procedure are employed to handle the non-convex constraints. Numerical results compare the system performance under the two cases, and demonstrate the significant covert performance superiority of the sensing-based imperfect CSI model and NOMA over the general norm-bounded imperfect CSI model and the orthogonal multiple access scheme. Furthermore, the dual yet contradictory effects of sensing on covert communications are revealed. It is also found that Alice primarily utilizes Carol’s signal for sensing, while allocating almost all of Bob’s signal for communication
A viscosity-type Tseng's extragradient algorithm for bilevel split hierarchical variational inequalities with multiple output sets
No full textIn this paper, we introduce and study a new class of split inverse problems called bilevel split hierarchical variational inequality problem with multiple output sets in the framework of real Hilbert spaces. We propose a viscosity-type Tseng's extragradient method for solving this problem when the cost operators are pseudomonotone. Under mild conditions, we obtain a strong convergence result for the proposed algorithm. Finally, we present numerical experiments to illustrate the applicability of our method
Prognostic factors for age-related macular degeneration progression: An overview of systematic reviews
No full textAge-related macular degeneration (AMD) is a progressive and irreversible degenerative disease of the retina. Slowing progression to late AMD is the only way to prevent vision loss. Given that AMD treatments are noncurative, understanding the personal characteristics associated with progression is of critical importance for people with increased AMD risk. We conducted an overview of systematic reviews and meta-analyses (SRMAs) to assess the scope of the existing literature on prognostic factors (PFs) for AMD progression. We included all systematic reviews of PFs for the progression of AMD from early or intermediate to late. We used the Cochrane Eyes and Vision Database of Systematic Reviews (current to September, 2024). We identified 64 potentially relevant studies in the database and included 17 SRMAs, which most commonly studied functional or structural ocular (10/17), lifestyle (7/17), and intervention-related factors (7/17). Across all reviews, 218 PFs were reported. We extracted 79 and grouped these into 20 distinct types of PFs across 8 categories. The modifiable PFs with most evidence for slowing progression were increased dietary supplementation with antioxidants and multivitamins and reduced smoking. Most PFs were non modifiable. Although most PFs may not be targetable, by integrating high-risk optical coherence tomography findings, monitoring relevant comorbidities, and considering individual lesion characteristics, clinicians may better predict disease trajectories and support patients in slowing progression and preserving vision. Notably, no reviews studied social determinants as potential PFs for AMD progression, representing a critical gap in the evidence base. Future reviews should investigate social, systemic, and AI-identified biomarkers to provide a more comprehensive understanding of AMD progression
Lessons on multicellular two- (2D) and three-dimensional (3D) culture in parasitology: Insights, challenges and future directions
No full textAdvances in multicellular two-dimensional (2D) and three-dimensional (3D) cell culture systems are providing parasitologists with new tools to investigate host-parasite interactions in vitro. These models offer tissue-specific and, increasingly, host-specific alternatives to traditional 2D monoculture and animal systems, with applications across protozoan and helminth biology. Spheroids, organoids, and emerging assembloid platforms capture key aspects of tissue architecture and function, enabling co-culture of parasites and their products, including dynamic analysis of interactions at defined host interfaces. In recent years, these systems have been adapted to model infection processes, parasite development, immune modulation and tissue remodelling across a range of parasite taxa and tissue types, particularly of the gastrointestinal tract. This review outlines applications of multicellular 2D and 3D cell culture systems in parasitology, drawing on examples from both human and veterinary research. We highlight lessons learned from published works to date that have accelerated the uptake and refinement of these approaches. We also examine technical challenges, including issues of standardisation, scalability, model accessibility, and species representation, particularly for livestock hosts. Looking ahead, the integration of immune, stromal, and microbial components into these models, as well as advances in imaging and omics technologies, and CRISPR-Cas9-mediated engineering of host organoids, promise increasingly sophisticated platforms for studying parasite biology, host tissue responses and pathogenesis. With continued investment and cross-disciplinary collaboration, multicellular culture systems are poised to play a central role in reducing animal use, improving model predictiveness, and supporting the development of next-generation antiparasitic therapies and interventions, including drugs and vaccines
Mapping the landscape of rural cancer research: a global bibliometric analysis
No full textPurpose: Rural communities frequently experience inequalities in cancer care compared to urban counterparts. Despite growing academic interest, there has been no global bibliometric analysis of rural cancer publications. Increasingly, global policies focus on place-based health inequalities; it is critical to understand the current state and emerging trends of rural cancer research. This analysis focuses on publication trends, including authors, citations, geography, collaboration (extent and patterns) and target journals. Methods: Web of Science and Scopus were searched from inception to 25th February 2025. Bibliometric methodology examined citation counts, authorship and publication sources. Results were converted into bibliographic data frames using the bibliometrix R package. All analysis and visual illustrations were in R 4.4.2. Results: Fifteen thousand seven hundred and twenty two documents were analysed (mean age, 10.6 years; average, 25.5 citations per document (2.2 per year)). Annual publication growth was 4.6%, with a marked increase in rural cancer research outputs since 2006. Research output was concentrated in a small number of high-income countries and institutions, but citation analysis showed that some smaller countries produced high-impact work. Rural cancer research activity is shaped by national, regional and geopolitical collaborations. Thematic gaps were identified in early diagnosis. Cancer-specific journals have most outputs, with rural health and public health journals also contributing to the dissemination of rural cancer research. Conclusion: Rural cancer research is expanding but is geographically uneven. There is a need for increased investment in underrepresented regions and broader subject-specific coverage that is guided by intersectional and place-based approaches
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/
Retinal biomarkers for Alzheimer’s disease in the prodromal and preclinical population - The Deep and Frequent Phenotyping study
No full textBACKGROUND: Recent challenges for disease-modifying therapies for Alzheimer's disease (AD) highlighted the need for biomarkers in the prodromal and preclinical stages. The Deep and Frequent Phenotyping (DFP) study aims to identify biomarkers for use in proof-of-concept trials. The DFP combines established AD markers with experimental approaches, including multimodal retinal imaging. Here, we report the baseline retinal vascular characteristics from ultra-widefield retinal images and retinal thickness measurements from Optical Coherence Tomography (OCT). METHOD: Participants were recruited aged ≥60 years with prodromal AD and control participants in a 4:1 ratio. Retinal vascular parameters (RVPs) were extracted from OPTOS ultrawide-field (UWF) images. Fractal dimension (FD), width gradient (WG), width intercept (WI), and tortuosity (TORT) were measured using the VAMPIRE software. OCT images were segmented with Heidelberg Eye Explorer (Heyex) to acquire the Retinal and Retinal Nerve Fibre Layer (RNFL) thickness. Associations between RVPs and AD risk factors (Family History of Dementia (FHD) and ApoE4 carrier status) were analysed in R, with results reported as medians and interquartile ranges. RESULT: FHD (n = 40) demonstrated significantly higher FD (1.13 [1.12, 1.15] vs 1.15 [1.13, 1.15], p <0.01) arterial WI (122μm [110, 132] vs 111μm [102, 129], p <0.05) alongside a lower arterial WG (-3.28μm/mm [-3.87, -2.74] vs -2.90μm/mm [-3.28, -2.35], p <0.05) compared to those without FHD (n = 51). ApoE4 carriers (n = 11) exhibited reduced arteriolar (100μm [94, 115] vs. 115μm [105, 121], p <0.05) and venular (131μm [121, 142] vs. 152μm [136, 159], p <0.05) WI compared to non-carriers (n = 80). No significant associations (p >0.05) were seen between TORT and FHD or ApoE4 status. FHD (n = 41) displayed a trend towards RNFL thickening in the Nasal (77μm [69, 87] vs 82μm [75, 90], p = 0.09) and inferotemporal (137μm [124, 148] vs 149μm [127, 158], p = 0.095) regions, compared to those without FHD (n = 48). No significant trends at baseline were observed between retinal thickness and FHD or ApoE4 status. CONCLUSION: These findings suggest that Retinal vascular parameters from OCT and UWF images may serve as non-invasive biomarkers for AD risk, offering a scalable early detection and monitoring method. Future work will focus on longitudinal data to assess trends and their role in tracking disease progression.</p
Policy design in zero-trust distributed networks: challenges and solutions
No full textTraditional security architectures are becoming more vulnerable to distributed attacks due to significant dependence on trust. This will further escalate when implementing agentic AI within the systems, as more components must be secured over a similar distributed space. These scenarios can be observed in consumer technologies, such as the dense Internet of things (IoT). Here, zero-trust architecture (ZTA) can be seen as a potential solution, which relies on a key principle of not giving users explicit trust, instead always verifying their privileges whenever a request is made. However, the overall security in ZTA is managed through its policies, and unverified policies can lead to unauthorized access. Thus, this paper explores challenges and solutions for ZTA policy design in the context of distributed networks, which is referred to as zero-trust distributed networks (ZTDN). This is followed by a case-study on formal verification of policies using UPPAAL. Subsequently, the importance of accountability and responsibility in the system’s security is discussed
Safety and efficacy of a feed additive consisting of 4-hydroxy-2,5-dimethylfuran-3(2H)-one for all animal species other than dogs and cats (ADISSEO France SAS, ADM International Sàrl, Laboratoires Phodé S.A.S., LUCTA S.A., Norel, S.A.)
No full textFollowing a request from the European Commission, EFSA was asked to deliver a scientific opinion on the authorisation of a feed additive consisting of 4-hydroxy-2,5-dimethylfuran-3(2H)-one for all animal species other than dogs and cats. 4-Hydroxy-2,5-dimethylfuran-3(2H)-one is currently authorised for use as a sensory additive (functional group: flavouring compounds) for cats and dogs at a recommended maximum content of 18 and 25 mg/kg complete feed, respectively. The FEEDAP Panel concludes that the use of the additive 4-hydroxy-2,5-dimethylfuran-3(2H)-one at the maximum use level proposed by the applicants (10 mg/kg complete feed) is safe for all animal species other than cats and dogs. 4-Hydroxy-2,5-dimethylfuran-3(2H)-one is safe for consumer and environment, however, it is irritant to skin, eyes and is a dermal and respiratory sensitiser. It should be considered irritant to the respiratory tract. Any exposure is considered a risk. 4-Hydroxy-2,5-dimethylfuran-3(2H)-one is used in food as a flavouring and its function in feed is essentially the same as that in food. Moreover, the Panel notes that the additive is already authorised in feed for cats and dogs. Therefore, no further demonstration of efficacy is necessary.</p