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Higher-order Laplacian renormalization
No full textThe renormalization group is a pillar of the theory of scaling, scale invariance and universality in physics. Recently, this tool has been adapted to complex networks with pairwise interactions through a scheme based on diffusion dynamics. However, as the importance of polyadic interactions in complex systems becomes more evident, there is a pressing need to extend the renormalization group methods to higher-order networks. Here we fill this gap and propose a Laplacian renormalization group scheme for arbitrary higher-order networks. At the heart of our approach is the introduction of cross-order Laplacians, which generalize existing higher-order Laplacians by allowing the description of diffusion processes that can happen on hyperedges of any order via hyperedges of any other order. This approach enables us to probe higher-order structures, define scale invariance at various orders and propose a coarse-graining scheme. We validate our approach on controlled synthetic higher-order systems and then use it to detect the presence of order-specific scale-invariant profiles of real-world complex systems from multiple domains.</p
Does Dietary Supplementation With Quercetin or Rutin Impact Growth, Stress, and Immunity in Pikeperch (Sander lucioperca) and the Water Microbial Community in Recirculating Aquaculture?
No full textPikeperch Sander lucioperca is a species mainly reared in recirculating aquaculture systems (RASs), but it remains very sensitive to stress and handling. Plant phenolic compounds such as quercetin or rutin are frequently investigated as feed additives to improve the growth and well-being of fish reared in RAS, but their impact on pikeperch and RAS microbial communities has never been studied. Our objectives were to (i) test the effect of quercetin or rutin addition to feed (2.2 g kg−1 diet) on the growth, stress, and innate immunity of pikeperch reared in RAS and (ii) assess the consequence of those additives on the RAS water microbial communities. Pikeperch of 307 (±45) g starting weight were reared in nine experimental RAS (n = 3) and fed for 84 days on a diet enriched or not (control treatment) with quercetin or rutin (feeding rate: 1.5%). Considering the start (T0) and the end (T84) of the experiment, we compare the fish growth, feed conversion ratio (FCR), morphoanatomical and physiological status, and the water microbial diversity and composition through a metabarcoding approach performed on the 16S rRNA gene. Whereas no effect on fish was recorded with quercetin (624.0 ± 21.9 g final weight), rutin (558.0 ± 10.7 g final weight) reduced pikeperch growth (0.54 vs. 0.69%–0.64% day−1), and increased FCR (1.70 vs. 1.2–1.4) compared to control (622.0 ± 16.8 g final weight) and quercetin treatments, respectively. No effect was observed on all fish physiological parameters analyzed separately, but a multifactorial analysis reveals that fish fed with rutin have a different overall physiological state. Quercetin induced a shift in the microbial community structure and composition, whereas there was no effect of treatments on microbial richness or evenness. A dietary supplementation with quercetin or rutin has no or a negative impact on pikeperch growth and physiology and modifies the microbial diversity in RAS. Effects of additives being species-dependent, precautions must be taken when formulating feed supplements, which must be based on precise studies.</p
Cancer-treatment-induced accelerated aging in older adult cancer survivors:A call for actions for future perspectives in geriatric oncology
No full textCancer treatment has significantly improved survival rates, but older adult cancer survivors remain at risk of cancer-treatment-induced late effects such as cardiac complications and second primary cancers. A new hypothesis emerged in the literature suggesting that such late effects can indeed be the manifestation of an accelerated aging process induced by cancer treatments. The cancer-treatment-induced accelerated aging could first arise from clinical and biological manifestations such as frailty, sarcopenia, cognitive impairments, cellular senescence, telomere attrition, and chronic inflammation, paralleling hallmarks of aging. Older adult cancer survivors frequently demonstrated early-onset frailty, sarcopenia, osteoporosis, cognitive impairments, diminished physical function, and increased levels of aging biomarkers compared to cancer-free age-matched older adults. However, existing studies are limited by their narrow focus on specific cancers, the use of single aging outcome measures, and short follow-up durations. A holistic research approach, incorporating comprehensive geriatric assessments and aging biomarkers, is crucial for describing the induced health burden and the mechanisms underlying these induced aging vulnerabilities. Addressing these gaps through large-scale longitudinal studies could lead to personalized interventions, improved treatment protocols, and supportive care strategies in older adult cancer survivors. Such efforts will enhance quality of life, promote healthy aging trajectories, and mitigate societal and economic burdens. To this end, concrete actions, such as establishing international consortia that include patient advocacy, are encouraged. Efforts should also include developing a centralized, registry-based repository for clinical and biological aging outcomes
Semi-dry transfer of CVD graphene on Si surface morphology and electronic properties
No full textTo expand the possible applications, chemical vapor deposition grown graphene needs to be transferred to appropriate substrates such as a silicon wafer. Although enormous efforts have been devoted to transfer graphene to various substrates using many different methods, the quality of the final product is still insufficient. We develop a new process named semi-dry transfer, which combines wet etching and dry transfer to obtain graphene with a clean interface with the substrate. For this purpose, an adhesive tape is attached to a sacrificial polymer deposited on the synthesized graphene, which allows the graphene to be easily manipulated so that it can be carefully cleaned before being precisely transferred onto target substrates, here silicon (Si) surfaces. We used this technique to transfer up to 4 × 4 cm2 of graphene onto SiO2/Si substrates. Using various analysis techniques such as low energy electron diffraction, scanning electron microscopy, scanning tunneling microscopy/spectroscopy, Raman, Auger electron and X-ray photoelectron spectroscopies, we demonstrate that our transferred graphene on Si is continuous, clean and that it is very promising for device fabrication. Graphene transistors show transport properties comparable with the state-of-the-art
Légiférer le numérique en période de pandémie:quand la maladie révèle les péchés capitaux du législateur
No full textUn environnement cashless au bout du smartphone, ou comment les services privés essentiels se digitalisent et discriminent
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PyFCG:Fluid Construction Grammar in Python
Get PDFWe present PyFCG, an open source software library that ports Fluid Construction Grammar (FCG) to the Python programming language. PyFCG enables its users to seamlessly integrate FCG functionality into Python programs, and to use FCG in combination with other libraries within Python's rich ecosystem. Apart from a general description of the library, this paper provides three walkthrough tutorials that demonstrate example usage of PyFCG in typical use cases of FCG: (i) formalising and testing construction grammar analyses, (ii) learning usage-based construction grammars from corpora, and (iii) implementing agent-based experiments on emergent communication
Unlocking the Acidity-Reactivity Correlation of Metal(IV)-Doped Silica Nanotubes in the Conversion of Ethyl Levulinate
No full textMetal-doped hollow silica nanotubes (M-NT, where M = Ti, Zr, Hf) were successfully synthesized via a straightforward impregnation of pristine hollow silica nanotubes with M-acetylacetonate solutions. After their characterization, the materials were tested as heterogeneous catalysts for the conversion of ethyl levulinate (EL) into γ-valerolactone (GVL) revealing highly promising activity for the target reaction. Special emphasis was given on disclosing the influence of the nature of the acid sites (Lewis or Brønsted) and their strength on the catalytic performances. Ammonia temperature programmed desorption (NH3-TPD), 31P solid-state nuclear magnetic resonance (31P-ssNMR) of trimethylphosphine and FT-IR of adsorbed ammonia, were the key techniques to evaluate the structure–activity correlation. The best solid exceeds the activity of other reference catalysts reported in the literature and tested under similar reaction conditions. The efficient recyclability of the best catalyst of the series was evaluated as well. The low E-factor obtained further confirmed the overall sustainability of the process.</p