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Zebrafish as a Model Organism for Research in Rare Genetic Neuromuscular Diseases
No full textThe zebrafish (Danio rerio) has become one of the most popular and valuable model organisms for studying rare neuromuscular diseases. Its unique characteristics, including the high number of offspring produced with each mating, transparent eggs, rapid development, and genetic similarity to humans, make this small vertebrate ideal for investigating complex and rare disorders affecting the skeletal muscle, such as Duchenne Muscular Dystrophy (DMD), Limb Girdle Muscular Dystrophies (LGMDs), and Brody Myopathy (BM). Various zebrafish models, both natural mutants and genetically engineered strains, have been developed to study these conditions. These models enable the deciphering of pathogenetic mechanisms, the real-time monitoring of disease progression, high-throughput drug screening, and the testing of novel therapeutic approaches. As research progresses, zebrafish models are likely to play an increasingly crucial role in unravelling the complexities of rare neuromuscular diseases and developing targeted therapies, offering hope for affected patients
Observation of cortical state-based learning in infants in a functional near-infrared spectroscopy paradigm
No full textSignificance: Learning can be context-dependent, with better outcomes under some circumstances than others. Adult functional magnetic resonance imaging studies have shown that learning outcomes vary as a function of participants’ brain states—patterns of intrinsic neural activity—prior to the learning task. Whether this is also the case in young infants is currently unknown. We report the first functional near-infrared spectroscopy (fNIRS) study that shows prior brain state-dependent learning in a language task in 6.5-month-old infants. Babies whose functional connectivity was lower in the right hemisphere, but not in the left, during a 2-min period prior to the task learned better a grammatical regularity in an artificial grammar learning task. Aim: Adult neuroimaging studies have shown that variability in brain states immediately before specific learning tasks is correlated with variability in learning outcomes. Whether the developing infant brain also shows similar state-based learning is currently unknown. Approach: We have explored whether 6.5-month-old infants’ ability to learn artificial grammar was related to their brain state during a 2-min baseline period of rest prior to the grammar task. We have asked if functional connectivity, a global metric of the cortical brain state, as measured by fNIRS, is correlated with learning a non-adjacent regularity in the artificial grammar task. Results: We have found that the overall level of functional connectivity in the 2-min period immediately prior to the learning experience is negatively correlated with the fNIRS measure of learning in the right hemisphere but not in the left. Conclusions: We show for the first time that the cortical state of an infant immediately prior to a learning experience determines how well that infant learns and that this can account for some of the variability in learning outcomes
Evidence for Avalanche Operation in Sub-Micrometer Power GaN HEMTs with p-GaN Gate
No full textWe demonstrate the existence of sustainable avalanche operation on 100 V lateral- power GaN HEMT with submicrometer gate length. Results show that: (a) current-voltage IDS-VDS measurements carried out as a function of device geometry demonstrate a significant and repeatable increase in drain current for voltages around 160 V (for the standard device geometry), corresponding to sustainable breakdown operation. Such phenomenon is only observed in 'reference' pinch-off conditions (VGS=0V), i.e. when a small sub-threshold current can flow through the devices. On the other hand (b), in 'strong pinch-off' conditions (VGS=-7 V), sustainable breakdown is not present, and devices reach a catastrophic failure (at higher voltage), due to the breakdown of the dielectric between field plate and drain. c) electroluminescence measurements indicate the presence of band-to-band luminescence, ascribed to the recombination of the holes generated by impact ionization (i.i.) with electrons near the source. d) temperature-dependent measurements indicate a positive temperature coefficient of the avalanche voltage
Topological singularities arising from fractional-gradient energies
No full textWe prove that, on a planar regular domain, suitably scaled functionals of Ginzburg–Landau type, given by the sum of quadratic fractional Sobolev seminorms and a penalization term vanishing on the unitary sphere, -converge to vortex-type energies with respect to the flat convergence of Jacobians. The compactness and the - follow by comparison with standard Ginzburg–Landau functionals depending on Riesz potentials. The -, instead, is achieved via a direct argument by joining a finite number of vortex-like functions suitably truncated around the singularity
Partial replacement of fish meal with hydrolised feather meal in the diet of giant river prawn (Macrobrachium rosenbergii) during the nursery phase
No full textThis study evaluates the effects of hydrolysed feather meal (HFM) inclusion in giant river prawn (Macrobrachium rosenbergii) post larvae diets, assessing growth performance, digestive enzyme activity, antioxidant status, and whole-body composition. Hydrolysed feather meal inclusion up to 6% improved growth performance, feed conversion, and welfare in giant freshwater prawns without compromising digestive enzyme activity or antioxidant status. These findings suggest that HFM is a viable alternative protein source that supports efficient digestion and shrimp health. Additionally, its use promotes circularity also in crustacean aquaculture by valorising poultry by-products, reducing reliance on traditional protein sources, and enhancing the sustainability of prawn production
Emprical Insights into Enhanced PCM Cold Storage: Experimental Results from the ECHO Project for Sustainable Cooling
No full textEuclid preparation LX. The use of HST images as input for weak-lensing image simulations
No full textData from the Euclid space telescope will enable cosmic shear measurements to be carried out with very small statistical errors, necessitating a corresponding level of systematic error control. A common approach to correct for shear biases involves calibrating shape measurement methods using image simulations with known input shear. Given their high resolution, galaxies observed with the Hubble Space Telescope (HST) can, in principle, be utilised to emulate Euclid observations of sheared galaxy images with realistic morphologies. In this work, we employ a GalSim-based testing environment to investigate whether uncertainties in the HST point spread function (PSF) model or in data processing techniques introduce significant biases in weak-lensing (WL) shear calibration. We used single Sérsic galaxy models to simulate both HST and Euclid observations. We then 'Euclidised' our HST simulations and compared the results with the directly simulated Euclid-like images. For this comparison, we utilised a moment-based shape measurement algorithm and galaxy model fits. Through the Euclidisation procedure, we e_ectively reduced the residual multiplicative biases in shear measurements to sub-percent levels. This achievement was made possible by employing either the native pixel scales of the instruments, utilising the Lanczos15 interpolation kernel, correcting for noise correlations, and ensuring consistent galaxy signal-to-noise ratios between simulation branches. Alternatively, a finer pixel scale can be employed alongside deeper HST data. However, the Euclidisation procedure requires further analysis on the impact of the correlated noise, to estimate calibration bias. We found that additive biases can be mitigated by applying a post-deconvolution isotropisation in the Euclidisation set-up. Additionally, we conducted an in-depth analysis of the accuracy of TinyTim HST PSF models using star fields observed in the F606W and F814W filters. We observe that F606W images exhibit a broader scatter in the recovered best-fit focus, compared to those in the F814W filter. Estimating the focus value for the F606W filter in lower stellar density regimes has allowed us to reveal significant statistical uncertainties
Vegetation changes the trajectory of river bends
No full textA primary axiom in geoscience is that the evolution of plants drove global changes in river dynamics. Notably, the apparent sinuosity of rivers, derived from the variance of sediment accretion direction measured in rocks, substantially increased when land plants evolved, around 425 million years ago. this led to the hypothesis that the rise of vegetation triggered river meandering. Recent studies of barren, meandering rivers challenge this notion, but the Paleozoic shift in the geometry of river deposits remains unexplained. Here, we suggest that it occurred because vegetation changes how river bends move through space. using satellite images to monitor river migration, we found that bank vegetation alters the orientation of point bar accretion, resulting in a 62% increase in the inferred variance of flow direction. these results explain why meandering rivers have been underrecognized in prevegetation stratigraphy
Modelli bioelettronici umani innovativi come alternativa alla validazione animale per una più efficace predizione del rischio cardiotossico e per la salvaguardia della biodiversità
No full textThe increasing need for effective drug safety evaluation preventing cardiotoxicity highlights the importance of developing physiologically relevant models. This study presents a novel concept of tissue-engineered myocardium, specifically conceived for in vitro cardiotoxicity risk prediction and generated with decellularized extracellular matrix (dECM) hydrogel scaffold derived from porcine ventricular myocardium and cardiomyocytes derived from the differentiation of human induced pluripotent stem cells (hiPSC-CMs). Optimized decellularization protocols, including automation, were designed to obtain acellular myocardial scaffolds, whose structural and biochemical components were preserved and supported subsequent hydrogel formation. This dECM hydrogel was shown to provide a cytocompatible 3D microenvironment for human bone marrow-derived mesenchymal stem cells, as demonstrated by cell proliferation over 10 days. These hosting properties were also demonstrated in combination with hiPSC-CM spheroids, allowing the manufacture of viable 3D engineered cardiac tissues. Thanks to a Multi-Electrode Array (MEA) platform, these engineered cardiac tissues were demonstrated to possess electrophysiological functionality and detectability, including stable field potential durations and conduction profiles. These findings emphasize the potential of this bioelectronic system to detect drug-induced arrhythmogenic risks and provide a reliable platform for cardiotoxicity testing, addressing critical gaps in preclinical drug development.
In addition, compared to traditional 2D and animal models, this in vitro 3D myocardial modeling concept offers a scalable, reproducible, and ethically superior alternative, reducing reliance on animal testing. By mimicking the native cardiac microenvironment and enabling high-throughput electrophysiological assessments, it represents a transformative tool for advancing cardiac drug safety evaluation and regenerative medicine. Future directions include further optimization for cardiomyocyte applications and clinical translation of its therapeutic potential, paving the way for its broader adoption in clinical and industrial settings
Soil policy principles and a policymaking framework using the soil security concept
No full textThere is a growing demand for more soil-centric policies to ensure sustainable land management and soil security. The concept of soil security enhances our understanding of soil multifunctionality as a comprehensive framework for soil protection. Utilising the soil security concept in policymaking can substantially improve the consistency and harmonisation of regional and global policies related to soil security. This paper reviews the fundamental aspects of the soil security concept, explores the diverse roles of soil, and proposes nine core principles for policymaking to guide the development of soil legislation. Comprehensive and effective soil policies should not only recognise these core principles but also encompass all dimensions of soil security. To illustrate this point, we analyse the current policy status and propose a policy framework for soil's role in climate change mitigation and adaptation, which is a prominent topic of environmental debate. Our approach demonstrates how the policy principles are reflected in the five dimensions of soil security, leading to a policymaking framework that is soil-centric, inclusive, and verifiable