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Published peer review reports have higher informative content than unpublished reports
No full textAlthough publishing peer review reports increases editorial transparency, little is known about the differences in terms of information content, readability and similarity between open and unpublished peer review reports across journals. We compared 140,844 published and 117,250 unpublished peer review reports from 233 medical journals published by Elsevier and Springer Nature between 2016 and 2021 using natural language processing. Our results showed that published peer review reports were longer and had more informative content, with the greatest difference found in the number of “suggestion and solution” sentences. Published peer review reports were also more readable and more similar to each other in terms of content structure. Reports by women had higher information scores and were more readable than reports by men, while reports by reviewers from non-Western institutions had lower information scores and were less readable than reports by reviewers from Western institutions. Our results suggest that increasing the transparency of review reports could lead to more detailed reports focusing on suggestions for improving manuscript
ANTIFUNGAL ACTIVITY OF NATURAL AND NATURAL-INSPIRED BIOACTIVE COMPOUNDS TO CONTROL THE RICE BLAST FUNGUS
No full textFungal pathogens pose a major threat to global agriculture and food security, with
intensive monoculture and resistance to single-site fungicides exacerbating the challenge
of effective crop protection. Among these pathogens, Pyricularia oryzae, the causal agent
of rice blast and of other cereals, is particularly devastating due to its rapid spread and
ability to infect multiple cereal crops. This thesis explores the discovery and development
of natural and nature-inspired compounds as multitarget biofungicides, aiming to interfere
with essential cellular processes and fungal virulence mechanisms.
A series of natural stilbenoids, including monomeric (deoxyrhapontigenin, pinostilbene,
DMHS) and dimeric compounds were synthesized and evaluated against both wild-type
and strobilurin-resistant P. oryzae strains. Deoxyrhapontigenin exhibited the highest
inhibitory activity on mycelial growth (60–80%), demonstrating potential as an
environmentally friendly antifungal agent. Stilbene derivatives merged with strobilurin
pharmacophores showed activity comparable to commercial fungicides, though their low
efficacy against resistant strains suggested retention of strobilurin-like mechanisms.
Ferroptosis, an iron-dependent form of regulated cell death, was investigated for its role in
appressorium maturation. A series of benzamides containing chelating catechol moieties
effectively suppressed appressorium formation, with activity partially reversible by adding
exogenous Fe
3
+, highlighting the critical link between iron homeostasis and fungal
virulence.
Additionally, phenylamides (PAs) derived from ferulic acid were synthesized and assessed
for antimicrobial potential. While these compounds modestly inhibited fungal growth, they
significantly impaired P. oryzae appressorium formation (up to 94%) and exhibited
antibacterial activity against foodborne pathogens, suggesting a dual role in plant
protection and food safety.
Phlorotannins, polyphenolic compounds from brown algae, were synthesized and
evaluated as antifungal agents. Polymethylated diphenyl ether derivatives showed
moderate mycelial growth inhibition (20–45%) across multiple fungal strains, indicating
that structural features such as methylation patterns influence bioactivity.
In vivo and in vitro studies of the most promising compounds—stilbenoids
(deoxyrhapontigenin, DMHS), siderophores (16a), phenylamides (feruloyl-agmatine 3f,
feruloyl-tyramine 3b), and phlorotannins (15)—demonstrated their capacity to impair
spore germination, appressorium formation, and fungal infection. Confocal microscopy
revealed that feruloyl-agmatine 3f partially inhibited autophagy-mediated nuclear
degradation, a process essential for appressorium maturation.
Overall, this thesis identifies natural and synthetic compounds that target multiple aspects
of P. oryzae pathogenicity, including spore germination and mycelial growth, or processes
indispensable for appressorium formation and maturation, such as ferroptosis and
autophagy. The findings provide a foundation for the development of environmentally
friendly biofungicides with novel molecular targets that interfere with until now little
explored biological processes involved in pathogenesis, and highlight innovative strategies
for durable rice blast management, offering significant potential for enhancing agricultural
productivity and food security
Beyond Water: Mapping Sediment Bars to Enhance Satellite Monitoring of River Dynamics
No full textUnvegetated sediment bars are central to river morphodynamics but are rarely used as indicators
of channel dynamicity in satellite‐based studies. Linking sediment dynamics and river lateral mobility requires
monitoring sustained changes in both water and sediment—the active channel (AC)—to avoid stage‐dependent
noise. Yet, such monitoring remains rare. We introduce an automated, globally applicable approach that detects
and quantifies activation (erosion) and deactivation (vegetation colonization) by tracking multi‐year sustained
AC directional shifts from Sentinel‐2 imagery. Applied to the Po River (Italy), this approach captures
trajectories across different morphologies, distinguishing lateral mobility, widening, and narrowing from
changes caused by stage‐dependent hydrological forcing. Results identify the exposed sediment‐to‐water ratio
as a strong predictor of AC dynamicity, with sediment‐rich reaches showing greater instability and
responsiveness to hydrological variations. Our findings demonstrate that incorporating sediment areas alongside
the water channel improves understanding of river dynamics, with implications for river restoration and risk
mitigation
Designing Surface Wettability for Enhanced Interfacial Phenomena
No full textModified wettability allows significant performance enhancements in materials and devices without changing their bulk composition, making it an attractive and cost-effective strategy for optimizing device efficiency. This work aims to modify the wettability of carbon materials, ranging from hydrophilic to superhydrophobic states, to enhance the performance of catalysts for Oxygen Reduction Reaction (ORR).
The studied carbons were Vulcan XC72 (Cabot Corporation), Acetylene Black Y70 and Acetylene Black YS (Orion Engineered Carbons). The properties of the powders were investigated through Dynamic Light Scattering (DLS) and Brunauer-Emmett-Teller analysis (BET). The wettability behaviour of the samples was studied on tablets, through the application and improvement of a literature kinetic model, and on films with different solvents. The influence of Nafion in the deposition was also studied.
Cyclic Voltammetry was used to study ORR using Rotating Ring Disk Electrode loaded with carbon. The electrochemical tests also included Double Layer Capacitance determination, H2O2 unwanted production and kinetic study with the application of Levich equation. The results highlighted that improved performances can be obtained with hydrophobic materials.
As final step, the properties of bare Vulcan XC72 and Pt/Vulcan XC72 at different wettability were evaluated with Zeta-potential, DLS and electrochemical tests
Antimicrobial Resistance: How Can We Overcome the Problem?
No full textAntimicrobials are common drugs used to treat and prevent infectious diseases in plants,
animals, and humans. Since their discovery in the mid-20th century, their use has dramati-
cally increased for the benefit of humanity, and also for animal care. However, antimicrobial
resistance soon appeared, which, according to the WHO, will limit or impede their use at the
horizon of 2050. Indeed, antimicrobial resistance (AMR), which is a natural phenomenon
in bacteria increased dramatically over the last 3 decades mainly due to the overuse and
misuse of antibiotics in humans, animals, and plants. Apart from affecting human health,
drug-resistant diseases also adversely affect plant and animal health, reduce agricultural
productivity, and threaten food security. AMR affects all countries, regardless of economic
status, and imposes high costs on health systems and national economies. Therefore, an-
timicrobial resistance should be studied and analyzed under the One Health paradigm. In
mind of the One Health paradigm, to reduce and overcome AMR, we must take at least 3
complementary and integrated actions: (i) monitoring the resistome; (ii) developing protec-
tive strategies against antibiotic resistance; (iii) taking curative actions by designing new
and original treatments. Moreover, the three actions must be conducted simultaneously
due to the continuous adaptation of bacteria
The role of fibration symmetries in geometric deep learning
No full textThis work extends the current framework of Geometric Deep Learning to incorporate local symmetries, specifically fibration symmetries, which are more commonly found in real-world data. By introducing these local symmetries, we improve the expressiveness and computational efficiency of Graph Neural Networks, which are widely used in machine learning for tasks involving structured data. This mathematical framework has implications that extend beyond graphs, providing a foundation for models of more complex structures, such as manifolds and grids. Our results provide insights that could enhance the generalization ability of machine learning models, making them more robust for diverse scientific applications. Geometric Deep Learning (GDL) unifies a broad class of machine learning techniques from the perspectives of symmetries, offering a framework for introducing problem-specific inductive biases like Graph Neural Networks (GNNs). However, the current formulation of GDL is limited to global symmetries. We propose to relax GDL to allow for local symmetries, specifically fibration symmetries, which only require isomorphic input trees—a property that is much more common in real-world graphs. We show that GNNs apply the inductive bias of fibration symmetries and derive a tighter upper bound for their expressive power. Additionally, by identifying symmetries in networks, we compress network nodes, thereby increasing their computational efficiency during both inference and training of deep neural networks. The mathematical extension introduced here applies beyond graphs to manifolds, bundles, and grids for the development of models with inductive biases induced by local symmetries that can lead to better generalization
Early hominins from Morocco basal to the Homo sapiens lineage
No full textPalaeogenetic evidence suggests that the last common ancestor of present-day humans, Neanderthals and Denisovans lived around 765-550 thousand years ago (ka)1. However, both the geographical distribution and the morphology of these ancestral humans remain uncertain. The Homo antecessor fossils from the TD6 layer of Gran Dolina at Atapuerca, Spain, dated between 950 ka and 770 ka (ref. 2), have been proposed as potential candidates for this ancestral population3. However, all securely dated Homo sapiens fossils before 90 ka were found either in Africa or at the gateway to Asia, strongly suggesting an African rather than a Eurasian origin of our species. Here we describe new hominin fossils from the Grotte & agrave; Hominid & eacute;s at Thomas Quarry I (ThI-GH) in Casablanca, Morocco, dated to around 773 ka. These fossils are similar in age to H. antecessor, yet are morphologically distinct, displaying a combination of primitive traits and of derived features reminiscent of later H. sapiens and Eurasian archaic hominins. The ThI-GH hominins provide insights into African populations predating the earliest H. sapiens individuals discovered at Jebel Irhoud in Morocco4 and provide strong evidence for an African lineage ancestral to our species. These fossils offer clues about the last common ancestor shared with Neanderthals and Denisovans
The Pseudomonas aeruginosa sirB2 gene is a fitness determinant of anaerobic growth and its inactivation affects virulence and rugose small colony variants emergence
No full textPseudomonas aeruginosa is the leading cause of death in cystic fibrosis (CF) patients, yet the genetic mechanisms driving its fitness in the host remain poorly defined. Previously collected transcriptomic data of clinical samples showed that expression of the gene PA14_RS04555 (sirB2) is stimulated in the CF lung environment. In this work, we show that sirB2 is regulated by the global transcriptional regulators Vfr and AmrZ. Loss of sirB2 markedly enhanced P. aeruginosa pathogenicity, increasing virulence in Galleria mellonella, and promoting bacterial translocation and biofilm formation in a differentiated airway epithelial infection model. Deletion of sirB2 triggered the emergence of biofilm-proficient rugose small colony variants (RSCVs), driven by elevated c-di-GMP and increased Pel polysaccharide production when cultures were grown in static conditions. The RSCV phenotype depends on suppressor mutations in the wsp operon, possibly as a response to redox imbalance caused by the lack of sirB2 under oxygen-limited conditions. Indeed, the sirB2 mutant exhibited impaired fitness during anaerobic respiration when nitrate was the sole electron acceptor, in a manner independent of the ubiquinone pool. Our findings show that sirB2 inactivation promotes RSCV emergence and identify sirB2 as a novel genetic determinant of metabolic fitness under host-relevant conditions, thereby underscoring the role of redox balance in chronic CF infections
A Protoplanet Candidate in the PDS 66 Disk Indicated by Silicon Sulfide Isotopologues
No full textDespite observational progress in planet formation, the stage in which planetesimals grow into planets remains
poorly understood. During this phase, protoplanets may develop gaseous envelopes that are warmer than the
surrounding disk gas, potentially providing observable signatures through molecules otherwise depleted in cold
regions. In this Letter, we report the detection of the silicon sulfide isotopologues 28SiS J = 16−15 and
30SiS J = 18−17 in the protoplanetary disk around PDS 66 (MP Mus) at a significance of ∼5σ−6σ, using the
Atacama Large Millimeter/submillimeter Array. These constitute the second and first detections of 28SiS and
30SiS in a protoplanetary disk, respectively. The emission appears as a compact source at r = 60 au in the
southwestern region of the disk, unresolved with a0 . 5 beam, and shows a velocity consistent with Keplerian
rotation, suggesting a protoplanetary origin. By modeling the line fluxes, we constrain the emitting radius to ∼0.5
−4 au and estimate a SiS mass of 1022–1023 g, corresponding to at least ∼10% of the silicon contained in local
dust grains. Because complete sublimation of a substantial fraction of dust grains by local processes is difficult to
achieve, this result instead implies an accumulation of silicon from a larger region. We propose that a
circumplanetary envelope surrounding a low-mass protoplanet, where pebble accretion and subsequent
sublimation of grains may enhance gaseous silicon abundance with respect to observable dust grains around it,
can account for the observed characteristics