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Comparing acoustic and digital piano actions: data analysis and key insights
No full textThe acoustic piano and its sound production mechanisms have been extensively studied in the field of acoustics. Similarly, digital piano synthesis has been the focus of numerous signal processing research studies. However, the role of the piano action in shaping the dynamics and nuances of piano sound has received less attention, particularly in the context of digital pianos. Digital pianos are well-established commercial instruments that typically use weighted keys with two or three sensors to measure the average key velocity-this being the only input to a sampling synthesis engine. In this study, we investigate whether this simplified measurement method adequately captures the full dynamic behavior of the original piano action. After a brief review of the state of the art, we describe an experimental setup designed to measure physical properties of the keys and hammers of a piano. This setup enables high-precision readings of acceleration, velocity, and position for both the key and hammer across various dynamic levels. Through extensive data analysis, we examine their relationships and identify the optimal key position for velocity measurement. We also analyze a digital piano key to determine where the average key velocity is measured and compare it with our proposed optimal timing. We find that the instantaneous key velocity just before let-off correlates most strongly with hammer impact velocity, indicating a target for improved sensing; however, due to the limitations of discrete velocity sensing this optimization alone may not suffice to replicate the nuanced expressiveness of acoustic piano touch. This study represents the first step in a broader research effort aimed at linking piano touch, dynamics, and sound production
Genomic diversity in time and space in the toxic diatom Pseudo-nitzschia multistriata
No full textUnderstanding the origin and maintenance of genetic diversity is crucial to elucidate population dynamics of unicellular microalgae, their microevolutionary history and their adaptive ability. The planktonic, domoic acid- producing diatom Pseudo-nitzschia multistriata has a ubiquitous distribution in the world oceans and past population genetics studies, based on few genomic loci, have shown a clear temporal structure over different years in the Gulf of Naples (Italy). Despite the ecological and toxicological importance of this organism, detailed information on its diversity across the whole genome and at the population level is still lacking. We collected P. multistriata strains in the Gulf of Naples in five different years, obtained strains from the Adriatic Sea, the Gulf of Mexico and New Zealand coasts, and resequenced the whole genomes of a total of 28 strains at high coverage. While strains from the first three geographical areas were capable of producing the toxin domoic acid, the New Zealand strains had been reported to be non-toxic. A comparison of the domoic acid biosynthetic (dab) genes sequences between toxic and non-toxic strains showed very little variation among the strains, and no disrupting mutation was found in the dab genes in the non-toxic strains. On the other hand, the dab genes showed higher levels of expression in toxic strains than in non-toxic strains, suggesting that, in this species, absence of toxicity is explained by gene regulation rather than dab sequence divergence. Variant analysis showed stronger spatial than temporal genetic structuring and a clear separation was observed between the New Zealand strains and the others, the former having a greater content of genes under selection. Overall, the genomes of the different groups, including strains from a clonal bloom, did not appear to contain major rearrangements. Our findings contribute to enlarging our understanding of diatom diversity, a key factor underlying diatom success, and provide novel data on the longstanding problem of Pseudo-nitzschia toxicity
Flow-interruption experiments to quantify trace elements leaching from a shallow saline aquitard
No full textSalinity from reclaimed lands in coastal deltaic areas is of upcoming concern throughout the world due to the ongoing climatic change and the associated water resources overexploitation. Sub-irrigation in salinized deltaic soils can promote the transport of major and trace elements (TE) in groundwater. In this study, experiments on flow interruption in columns have been conducted for salinized peaty aquitard from the Po Delta using synthetic rainwater to replicate sub-irrigation practices and their effect on TE leaching. Non-equilibrium transport and cation exchange phenomena were assessed using a NaCl tracer test. This latter was also simulated via CXTFIT 2.0 to quantify sorption and physical non-equilibrium processes. Pre and post experiment sequential extraction allowed for the evaluation of geochemical alterations caused by the injection of the synthetic rainwater and the tracer solution into the reducing sediments. Results from the flow interruptions showed peaks of As, Mn, Pb, and Ni exceeding the World Health Organization standards for drinking water, indicating that irrigation periods are marked by the diffusion of trace elements hosted in exchange sites and solid phases. The employment of NaCl as a tracer resulted in a significant elution of trace elements due to Na+ exchange from clays and organic matter and retardation of Cl− due to diffusion into the osmotic membranes of organic fragments. The partial oxidation of pyrite and arsenopyrite to Fe(III) oxides contributes to the prolonged release of TE. These results highlight how alternating sub-irrigation in a peaty reducing environment can trigger the mobilization of TE in deltaic contexts. The findings of this study are of relevance, as similar hydrogeological settings are widespread globally. Indeed, in real-world scenarios, such as agricultural systems with intermittent irrigation or aquifer restoration strategies, flow interruptions are commonly utilized worldwide
Weakly Solvating Electrolytes for Lithium and Post-Lithium Rechargeable Batteries: Progress and Outlook
No full textIn the rapidly evolving global landscape of renewable energy sources, there is an increasing demand for high-energy-density rechargeable batteries essential for energy storage. Simultaneously, there is a growing emphasis on developing high-stability electrolytes. The concepts of high concentration electrolytes (HCEs) and localized high concentration electrolytes (LHCEs) have emerged, with notable progress achieved by altering cation-solvent and cation-anion solvation coordination environments. However, challenges persist, including high costs and low ionic conductivity. A recent development is the introduction of the weakly solvating electrolyte (WSE), which offers a new perspective on the design of stable electrolytes at conventional or low concentrations. This approach enables high-performance rechargeable batteries by modulating the coordination structure of electrolytes to generate a unique anion-driven interphase reaction chemistry. This review outlines the design principles of WSEs and their operating mechanisms when applied to rechargeable lithium and post-lithium batteries. An outlook is also presented on the future research directions of WSE, coupled with an analysis of the technological challenges
AIDEAS Smart Retrofit Solution: Architecture for Industrial Machines Interoperability
No full textIn the era of Industry 4.0, Smart Retrofit emerges as a pivotal strategy for enhancing industrial infrastructure efficiency, competitiveness, and sustainability. The presented Smart Retrofit solution developed for the AIDEAS project involves integrating hardware, software, and communication innovations into existing machinery to extend their lifespan and improve performance. The modular approach facilitates data collection, analysis, and performance optimization, enhancing industrial processes’ overall agility, sustainability, and resilience. Particularly relevant for Small and Medium Enterprises, this solution offers a cost-effective alternative to purchasing new equipment, allowing them to leverage their existing resources, retain invaluable internal expertise, and smoothly transition into the Industry 4.0 landscape. Key components of Smart Retrofit action encompass the implementation of Artificial Intelligence algorithms for data analysis, the incorporation of new sensors and technologies for data acquisition, and the development of user-friendly interfaces and security protocols
Ocean warming, marine heatwaves and phytoplankton biomass: long-term trends in the Northern Adriatic Sea
No full textIn the present study, we investigated the trends of Sea Surface Temperature (SST), marine heatwaves (MHWs) and phytoplankton biomass, in terms of chlorophyll-a (chl-a), in the Northern Adriatic Sea (NAS), and the potential effects of ocean warming onto chl-a. Deseasonalized trends, calculated to assess the general tendencies without the effect of seasonality, showed a general increase of SST, and a decrease of chlorophyll-a concentration in almost the entire NAS. The strongest increase in SST was found along the eastern coast and in offshore areas, whereas the most pronounced decrease in chl-a was observed along the western coast, especially near the Po River delta. Seasonally, these trends were generally more marked in spring and summer. Spatial and seasonal variability in MHWs mean values and trends were also observed across the basin. A different response of chl-a to SST anomalies was highlighted over time, with negative correlations spreading throughout the NAS at subsequent time (one month later), together with positive correlations in eutrophic lagoonal areas. Different case studies and cluster analysis were used to assess the effects of ocean warming, also related to MHWs, on phytoplankton biomass. The relationships varied based on the background trophic conditions: in oligotrophic regions, marine heatwaves and extreme heat conditions led to reduced chlorophyll-a concentrations, while the same conditions in eutrophic areas, such as the western coast and lagoons, caused an increase in phytoplankton biomass. Our results indicated that MHWs and SST increases, are among the factors that are affecting the phytoplankton communities of the NAS
Monitoring cellular dynamics upon infection using a holotomography-based approach
No full textMany intracellular bacteria interfere with mitochondrial dynamics or target other organelles, thereby inducing a specific cellular response that could emerge as a strategy of the pathogen to ensure its survival, or as a form of defense employed by the host cell to restrict dissemination. In this context, the concomitant monitoring of both pathogen migration and (intra)cellular dynamics in live cells emerges as a pivotal aspect for the comprehension of the infection sequence and to visualize the pathogen-mediated remodeling that could occur to the entire cellular system. Holotomographic microscopy can be used to achieve this goal, allowing the simultaneous analysis of both bacterial movement and intracellular alteration for extended periods of time, with high spatial resolution and avoiding side-effects due to phototoxicity. Here we provide a holotomography-based approach to detect Listeria monocytogenes dynamics and its effects on the entire cellular system at morphological level
Novel gait phases recognition framework leveraging the temporal structure of the myoelectric activity
No full textObjective. Reliable control of lower limb prostheses during gait using surface electromyography requires robust decoding of myoelectric signals to ensure safety and efficiency. Conventional myoelectric pattern recognition (PR) methods, which classify features extracted from each window, often yield inaccurate and unstable output, limiting their practical use. Approach. To deal with these issues, two novel temporal myoelectric-based gait phase recognition frameworks are presented. Temporal activation profile (TAP) considers a sequence of features extracted from consecutive windows, and dual activation shots (DAS) using features extracted from the current and a specific preceding window. These methods were tested on (1) publicly available SIAT-LLMD dataset of 40 healthy subjects under different locomotion conditions, and (2) two subjects with transfemoral amputation during normal walking. Main results. TAP and DAS significantly outperformed conventional PR methods, achieving accuracies of 88.50% and 87.97%, respectively, in healthy subjects during normal walking. TAP achieved optimal performance using features extracted from consecutive windows spanning 240 ms in the past, whereas DAS performed best when leveraging features from the current window combined with those from a window 160 ms prior. No significant differences were observed between TAP and DAS under optimal conditions. Both approaches effectively enhanced gait phase recognition performance when applied to transfemoral amputee gait data. The TAP framework achieved the highest performance, surpassing 87.80% accuracy with extended temporal context requirement, and outperforming the DAS approach (82.32%) under pathological conditions. Significance. Both TAP and DAS are robust solutions for gait phase recognition as they stabilize the decision output and reduce classification errors. DAS is more practically feasible due to lower temporal and computational demands, while TAP is more effective in the case of altered neuromuscular activation patterns. The findings of this paper highlight the potential of integrating these methods into real-time prosthetic controllers, ensuring safe and reliable use for patients
Celebrating the fifth edition of the International Symposium on Fungal Stress – ISFUS, a decade after its 2014 debut
No full textThe Fifth International Symposium on Fungal Stress (ISFUS) brought together in Brazil many of the leaders in the field of fungal stress responses, from fourteen countries, for four days of outstanding science ranging from basic research to studies with agricultural, medical, industrial, and environmental significance. In addition to the excellent oral and poster presentations, the Symposium organisers ensured that all participants had ample opportunity to engage, socialise, and network to exchange ideas and share research. The conference was enhanced by the world-class venue near Iguazu Falls, probably the greatest natural phenomenon in South America
Quantum Computational Methods for Higher Order Modes Detection in Transmission Lines
No full textThe efficient computation of higher-order modes in multiconductor transmission lines is crucial, as these modes alter the distribution of TEM modes and increase cross-talk, affecting electromagnetic compatibility and signal integrity in high-frequency circuits. Traditional numerical methods face challenges in handling large-scale eigenvalue problems due to increasing computational complexity. Quantum computing offers a promising alternative by leveraging quantum principles such as superposition and entanglement to solve large eigenvalue problems more efficiently than classical solvers. In this work, we explore the variational quantum eigensolver as a quantum-assisted method for waveguide modal analysis. Starting from the Helmholtz equation for TM modes, we discretize the system using the finite difference method, map the Hamiltonian onto the Pauli basis, and implement the VQE with a hardware-efficient ansatz optimized via BFGS on the Qiskit statevector simulator of IBM [1]. As a test case, we analyze a shielded stripline. The quantum eigensolver successfully computes the first two TM modes and their cutoff frequencies while reconstructing the Ez and Ex field distributions at 1 GHz. This preliminary study shows the feasibility of quantum algorithms for solving large eigenvalue problems in computational electromagnetics where classical computing can fail, opening new possibilities for the efficient analysis of shielded multiconductor transmission lines, where higher-order modes significantly impact cross-talk and signal integrity. Future work will focus on scaling this approach to analyze multiconductor propagation in complex transmission-line structures