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PASS-based multi-user communications: capacity characterization and configuration strategy
No full textThe fundamental capacity limits of pinching-antenna systems (PASS)-based multi-user communication network are investigated. Two practical pinching-antenna configuration strategies are considered, namely multiple-time discrete activation and one-off continuous sliding. For each strategy, the capacity and rate regions are characterized under the non-orthogonal multiple access (NOMA) and orthogonal multiple access (OMA) schemes, respectively. 1) For NOMA, the capacity region achieved by the discrete activation is first characterized. In particular, the ideal case with the infinite number of activation times is considered, where the optimal PA activation and resource allocation scheme is derived. It is shown that different user groups or decoding orders are served via time-sharing. Inspired by this result, an inner bound of capacity region is obtained for the practical case with a finite number of activation times. Then, for the continuous sliding case, the inner bound of capacity region is characterized by alternately optimizing the resource allocation and PAs’ continuous positions. 2) For OMA, the rate region is first obtained for the discrete activation case. It is unveiled that multiple users are successively served. Then, by alternately optimizing the resource allocation and PAs’ continuous positions, the inner bound of rate region is obtained for the continuous sliding case. Numerical results demonstrate that i) PASS can significantly improve the capacity performance compared with the conventional fixed-antenna systems; ii) the capacity gain can be further enhanced by using the proposed PA activation and sliding and resource allocation schemes; and iii) the continuous sliding has the potential to outperform the discrete activation in NOMA, whereas the latter performs better in OMA
Dynamic knowledge distillation for climate-driven diarrhoea incidence prediction
No full textDiarrhoeal disease remains a significant public health burden in Vietnam, with incidence strongly influenced by climatic variability. Accurate short- and long-term forecasts are essential for effective early warning systems (EWS) to enable timely interventions. We propose a Dynamic Knowledge Distillation Ensemble (DKDE) framework for provincial-scale diarrhoea incidence forecasting that integrates local climate predictors with spatially informed neighbour-incidence data. DKDE dynamically selects the most relevant teacher models for each province and forecast horizon, adaptively combining their predictions into a compact student model through a data-driven distillation process. Using monthly diarrhoea surveillance data from 55 provinces (1997-2017) and corresponding climate records, we evaluate DKDE against state-of-the-art deep learning models (PatchTST, LSTM, CNN, Transformer variants) and the best-known method on the same dataset, the Dynamic Weighted Ensemble (DWE). Across six forecast horizons, DKDE consistently outperforms all baselines, achieving its largest gains in short-term prediction—reducing average 1-month RMSE from 16.74 (DWE) to 16.57—while maintaining superior accuracy at longer horizons. Comprehensive ranking and performance-gap analyses demonstrate DKDE's robustness and stability across spatial and temporal scales.<br/
Role of blanket bog condition in stream dissolved organic carbon export
No full textThe degradation of peatlands across the UK and Ireland has led to rising concentrations of dissolved organic carbon (DOC) in surface waters. This can have implications for the treatment of water supplies. While catchment management strategies to improve water quality, such as peatland restoration, aim to reverse these trends and thereby reduce treatment costs, relationships between DOC generation and land use require further clarification. DOC levels recorded in discharge from relatively intact areas can be used to establish realistic restoration targets. To investigate the relationships between DOC concentrations in streams draining intact areas and adjacent disturbed areas, a year-long integrated hydrological and water quality monitoring program was conducted along a 2.2 km stretch of a first-order stream draining a blanket peat-covered catchment in the Ox Mountains, Co. Sligo, Ireland. Groundwater level monitoring operated continuously at 15 catchment locations in contrasting hydrological settings. Combining the results of continuous stream discharge measurements with groundwater level monitoring permitted event-based water quality sampling at three locations along the stream’s course; this allowed assessment of how changes in DOC concentrations and fluxes varied with land use, moving from the stream’s headwaters, downstream. Data from five water quality sampling events distributed over the course of one-year (December 2023 to November 2024) revealed that DOC fluxes draining the 107 ha catchment of the stream’s headwaters varied between 8.7 mg/m2 and 144 mg/m2. By contrast, DOC fluxes rose consistently going downstream. Results from the final 21 ha interval, (reflecting a substantially more degraded area) showed that fluxes from a formerly afforested peatland ranged from 27 mg/m2 to 907 mg/m2. The results indicated that DOC fluxes are affected by both peatland condition and seasonal variation
ATOMIUM: Continuum emission and evidence of dust enhancement from binary motion
No full textContext. Low- and intermediate-mass stars on the asymptotic giant branch (AGB) account for a significant portion of the dust and chemical enrichment in their host galaxy. Understanding the dust formation process of these stars and their more massive counterparts, the red supergiants, is essential for quantifying galactic chemical evolution. Aims. To improve our understanding of the dust nucleation and growth process, we aim to better constrain stellar properties at millimetre wavelengths. To characterise how this process varies with the mass-loss rate and pulsation period, we studied a sample of oxygen-rich and S-type evolved stars. Methods. Here we present ALMA observations of the continuum emission around a sample of 17 stars from the ATOMIUM survey. We analysed the stellar parameters at 1.24 mm and the dust distributions at high angular resolutions. Results. From our analysis of the stellar contributions to the continuum flux, we find that the semi-regular variables all have smaller physical radii and fainter monochromatic luminosities than the Mira variables. Comparing these properties with pulsation periods, we find a positive trend between the stellar radius and period only for the Mira variables with periods of more than 300 days, and we find and a positive trend between the period and the monochromatic luminosity only for the red supergiants and the most extreme AGB stars with periods of more than 500 days. We find that the continuum emission at 1.24 mm can be classified into four groups; (i) ‘featureless’ continuum emission is confined to the (unresolved) regions close to the star for five stars in our sample, (ii) relatively uniform extended flux is seen for four stars, (iii) tentative elongated features are seen for three stars, and (iv) the remaining five stars have unique or unusual morphological features in their continuum maps. These features can be explained by the fact that 10 of the 14 AGB stars in our sample have binary companions. Conclusions. Based on our results, we conclude that there are two modes of dust formation: well-established pulsation-enhanced dust formation and our newly proposed companion-enhanced dust formation. If the companion is located close to the AGB star, in the wind acceleration region, then additional dust formed in the wake of the companion can increase the amount of mass lost through the dust-driven wind. This explains the different dust morphologies seen around our stars and partly accounts for the large scatter in literature mass-loss rates, especially among semi-regular stars with small pulsation periods.</p
Programmable mesophilic argonaute-triggered SERS biosensor promotes amplification-free and multiplexed nucleic acid detection
No full textSimultaneous on-site identification of multiple nucleic acids with rapidity and accuracy has consistently posed a significant challenge in the analytical chemistry field. This is primarily because current methods predominantly rely on nucleic acid amplification while lacking high-resolution multi-signal output strategies. Inspired by that argonaute (Ago) endonuclease coupled with guide DNA (gDNA) can specifically cleave nucleic acid target and exhibit stepwise endonuclease activity for signal amplification, as well as the ultrasensitive detection capability and high-resolution signal differentiation of surface-enhanced Raman scattering (SERS), we proposed a novel programmable mesophilic Clostridium perfringens argonaute (CpAgo)-triggered SERS sensing platform (CpAgo-SERS) for amplification-free and multiplexed nucleic acid detection. In this platform, two-round continuous cleavage mediated by CpAgo/gDNA ensures both specific DNA recognition and efficient signal amplification. To further enhance the detection sensitivity, controllable polystyrene (PS) nanoparticles, with high loading capacity for signal molecules, were utilized to encapsulate Raman reporters to further amplify signal after target activated cleavage of CpAgo. Besides, the optimal functioning of mesophilic CpAgo at room temperature promotes the development of on-site detection techniques. Through these designs, this platform was capable of sensitively and simultaneously identifying multiple nucleic acids in one tube, achieving a limit of detection (LOD) of 0.497 ng/μL without any pre-amplification. Subsequently, we applied this method to animal-derived food authentication, which poses severe challenges to trace target detection due to complex matrices. The proposed strategy demonstrated satisfactory feasibility, indicating its great potential as a versatile toolbox for nucleic acid screening even in complex sample matrices
Effects of exposure to phthalates and a phthalate substitute on food sensitization in children in China: evidence from a population study
No full textBackgroundPhthalates are among the most ubiquitous environmental pollutants and endocrine disruptors. However, the effect of phthalates exposure on food allergies remains unclear.ObjectivesThis study examined the relationship between exposure to phthalates and a phthalate substitute and food sensitization in children.MethodsA study was conducted including 198 children with self-reported food allergy and 202 healthy children. Specific immunoglobulin E (sIgE) test and skin prick test were applied to evaluate the susceptibility to food sensitization. Urine samples were analyzed for 17 metabolites of phthalates and a phthalate substitute. Logistic regression and weighted quantile sum regression models were used to examine the correlations between exposure and food sensitization. Bayesian benchmark dose models were established to calculate benchmark dose values for these metabolites.ResultsIn single compound models, mono-2-ethyl-5-hydroxyhexyl terephthalate (MEHHTP) was associated with increased sensitization to almond, crab, shrimp, and total foods, and mono-2-methyl-2-hydroxypropyl phthalate (MHiBP) was associated with positive skin prick tests for wheat, peanut, and blue mussel (all p < 0.05). Mixed exposure only increased susceptibility for total foods sensitization with higher levels of sIgE (Odds Ratio = 1.25, 95 % confidence intervals: 1.01–1.56, p = 0.04), and MEHHTP had the dominant contribution.ConclusionPhthalates exposure is linked to a higher risk of food sensitization in children in China. Further studies are warranted to confirm these findings and the role of phthalate substitutes
Safety and efficacy of a feed additive consisting of Kieselguhr (diatomaceous earth) for all animal species (Imerys France)
No full textFollowing a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Kieselguhr (diatomaceous earth, three forms: natural, purified calcined and purified flux-calcined) as a technological additive (functional group: anticaking and binder) for all animal species. Kieselguhr is predominantly amorphous silica (non-crystalline silicon dioxide (SiO2)). Based on the information submitted, Kieselguhr natural, purified calcined and purified flux-calcined are safe when used at 5000 mg/kg of complete feed in all terrestrial animals. No conclusions can be reached on the safety of its use in aquatic animals. The use of Kieselguhr natural, purified calcined and purified flux-calcined in animal nutrition under the proposed conditions of use is safe for the consumer and the environment. Kieselguhr natural and purified flux-calcined are not irritant to the skin. All the three forms of the additive are irritant to the eyes and should be considered dermal and respiratory sensitisers. Any exposure is considered a risk. The FEEDAP Panel concluded that the additive is effective as a pellet binder. Kieselguhr is efficacious as an anticaking agent at a minimum concentration of 15,000 mg/kg.</p
Safety and efficacy of a feed additive consisting of vermiculite for all poultry and ornamental birds, all porcine species, equines, leporids, camelids, pets and other non-food-producing animals (Regal B.V.)
No full textFollowing a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of vermiculite as a technological feed additive for all poultry and ornamental birds, all porcine species, equines, leporids, camelids, pets and other non-food-producing animals. The FEEDAP Panel concluded that vermiculite is considered safe at 10,000 mg/kg complete feed for the use in feed for chickens for fattening and reared for laying/breeding and laying hens, and at 5000 mg/kg complete feed for piglets and pigs for fattening. No conclusion can be drawn on the safety of the product for ornamental birds, equines, leporids, camelids, pets and other non-food-producing animals. The Panel concluded that the use of vermiculite is safe for consumer and the environment. The additive is considered a skin and respiratory sensitiser. Inhalation and dermal exposure are considered a risk. Due to the lack of data, the Panel could not conclude on the potential of the additive to be an eye irritant. The FEEDAP Panel concluded that vermiculite is efficacious as anticaking agent in feed, when used at 10,000 mg/kg complete feed.</p
Safety of a feed additive consisting of zeolites (≥ 50%) obtained from Neapolitan Yellow Tufa for poultry for fattening or reared for laying/reproduction (Italiana Zeoliti s.r.l.)
No full textFollowing a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety of a feed additive consisting of zeolites (≥ 50%) as a technological feed additive for poultry for fattening or reared for laying/reproduction. In 2024, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) delivered an opinion on the safety and efficacy of the same additive. The Panel concluded that the use of the additive containing zeolites (≥ 50%) in animal nutrition is safe for the consumers and for the environment, and efficacious as an anticaking agent in feed for all animal species. The additive was not considered skin irritant. No conclusion could be reached on the eye irritancy and the respiratory and dermal sensitisation. Due to the dusting potential and its crystalline silica content, the additive was considered a risk by inhalation. In the current assessment, analytical data provided suggests that the inclusion of zeolites (≥ 50%) in poultry feed may interfere with the determination of aflatoxin B1. Regarding the target species, no conclusion could be drawn for poultry for fattening or reared for laying/reproduction. Based on the tolerance studies in chickens for fattening evaluated in the current assessment, the Panel concluded that the inclusion of zeolites (≥ 50%) at 12,500 mg/kg complete feed is safe for chickens for fattening or reared for laying/reproduction. No conclusion could be established on other poultry for fattening or reared for laying/reproduction.</p
Safety and efficacy of a feed additive consisting of L-arginine produced with Escherichia coli CCTCC M 20231961 for all animal species (Kempex Holland B.V.)
No full textFollowing a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of L-arginine produced with a genetically modified strain of Escherichia coli (CCTCC M 20231961) as a nutritional feed additive for all animal species and categories. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the production strain E. coli CCTCC M 20231961 does not raise safety concerns. No viable cells or DNA of the production strain are detected in the final product. Therefore, the FEEDAP Panel concludes that the additive does not pose any safety concern regarding the production strain. The use of L-arginine produced by fermentation with E. coli CCTCC M 20231961 in feed is safe for the target species when supplemented in appropriate amounts to the diet according to the nutritional needs of the target species. The FEEDAP Panel has concerns on the use of L-arginine in water for drinking. The use of L-arginine produced by fermentation with E. coli CCTCC M 20231961 in animal nutrition is considered safe for the consumers and for the environment. The FEEDAP Panel cannot conclude on the potential of the additive to be irritant to skin and/or eyes and to be a potential dermal sensitiser. The feed additive consisting of L-arginine produced by fermentation with E. coli CCTCC M 20231961 is regarded as an efficacious source of the amino acid L-arginine for all non-ruminant species. For the supplemental L-arginine to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.</p