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Multilayer networks describing urban interactions for building the digital twins of five cities in Spain
No full textNetworks specifying who interacts with whom are crucial for mathematical models of epidemic spreading. In the context of emerging diseases, these networks have the potential to encode multiple interaction contexts where non-pharmaceutical interventions can be introduced, allowing for proper comparisons among different intervention strategies in a plethora of contexts. Consequently, a multilayer network describing interactions in a population and detailing their contexts in different layers constitutes an appropriate tool for such descriptions. These approaches however become challenging in large-scale systems such as cities, particularly in a framework where data protection policies are enhanced. In this work, we present a methodology to build such multilayer networks and make those corresponding to five Spanish cities available. Our work uses approaches informed by multiple available datasets to create realistic digital twins of the citizens and their interactions and provides a playground to explore different pandemic scenario in realistic settings for better preparedness
Efficient topography simulation for freeform surfaces in 5-axis CNC milling
No full textAccurate prediction of surface micro-topography in 5-axis CNC milling is essential for achieving high-quality finishes in aerospace, biomedical, and precision engineering components. Traditional simulation methods like the Classical Z-Map often suffer from high computational cost and limited applicability to freeform surfaces. This paper presents RMAP, a fast and vectorized algorithm that enhances the Classical Z-Map by projecting cutter edge points in a locally transformed coordinate system aligned with the surface normal. The method supports arbitrary machining strategies exported from CAM software and is compatible with both ideal and realistic cutter edge geometries. Simulations were performed on a hyperbolic paraboloid surface using tool paths generated in NX CAM and validated experimentally on aluminum. RMAP achieved speedups up to 100x compared to Classical Z-Map, with relative errors below 6\% for key areal experimental parameters Sa and Sq. Notably, simulations incorporating realistic cutter edge imperfections, modeled with a stochastic distribution, accurately reproduced short-wavelength directional features observed in experimental measurements. The algorithm proved robust across multiple strategies, including 3-axis and 5-axis configurations with variable feed rates. By maintaining accuracy on complex freeform geometries and significantly reducing computation times, RMAP enables reliable and scalable topography simulation
Full Winter Season Measurement of Snowpack Height and Backscattering Coefficient Using a 120-GHz Ultrawideband FMCW Radar
No full textIn this article, we present a 120-GHz ultrawideband (3.3 GHz) frequency-modulated continuous wave (FMCW) radar, designed using a millimeter-wave (mmWave) transceiver, and its application to the measurement of snowpack height over two full winter seasons. This system achieves 2 cm accuracy across the diverse snowpack and environmental conditions encountered during the winter season. Its main advantages over conventional measurement techniques are good performance during heavy snowfall, correct detection of fresh fallen snow, spatial averaging, and low temperature dependence. Furthermore, our system is able to measure the backscattering coefficient of the snowpack, which is predominantly influenced by the liquid water content (LWC) of its surface layer. This relationship is confirmed by experimental measurements and numerical simulations, and could enable noninvasive first layer LWC estimations. Hence, we prove mmWave radar to be a reliable technology for snowpack monitoring under different environmental and snowpack conditions, with a wide range of applications in hydrological forecasting, avalanche risk assessment, and environmental monitoring
Life cycle assessment and multi-objective optimization of biogas upgrading using chitosan based composite membranes
No full textBiopolymer membranes, hybridized by non-toxic or renewable fillers are gaining attention on the preparation of membranes for CO2 separation, providing their flux and mechanical endurance is improved to provide environmental and economic viability as real alternatives in the decarbonization of the chemical industry. Cellulose acetate is the most commonly found natural biopolymer but its preparation needs organic solvents and it is prone to plasticization. Chitosan biopolymer can be produced from fish waste, but its mechanical resistance is limited due to its high hydrophilicity. In this work, chitosan was blended with cellulose acetate or starch, which can also be obtained from biowaste. The membranes were characterized by single N2, CH4 and CO2 gas permeation and also CO2/CH4 mixture separation. The CO2 permeance of CS:ST membranes was closer to commercial PDMS membrane, and the CO2/CH4 selectivity of CS:CA membranes was in the range of selective polymer membranes for this application. A sustainability assessment of the membrane fabrication was performed using Life Cycle Assessment with three environmental impact categories (ReCiPe midpoint method): Global warming, energy and materials depletion. A multi-objective optimization model was applied to optimize the process conditions in the simultaneous CO2 and CH4 recovery from model biogas feed stream optimal mass and energy balances. The optimized energy consumption for the separation was utilized on the evaluation of the cradle-to-gate environmental performance for the membranes attaining 90 % purity and recovery in CO2 and CH4 in the permeate and retentate outlet streams, respectively
Serum lncRNAs NEAT1, PVT1 and H19 as novel biomarkers for sarcopenia diagnosis and treatment response
No full textSarcopenia, the loss of muscle mass and function generally associated to age, leads to increased dependence and mortality in older adults. Despite its clinical significance, unclear molecular mechanisms hinder the development of universal diagnostic and therapeutic monitoring methods. Recent research suggests long non-coding RNAs (lncRNAs) as potential biomarkers for muscle damage and sarcopenia. This study investigates the role of six specific lncRNAs as biomarkers for diagnosing and monitoring sarcopenia following physical training. For this purpose, an initial cohort of participants was divided into two experiments: Trial 1, a cross-sectional study comprising 54 sarcopenic patients and 29 robust controls, both including men and women; Trial 2, a non-randomized controlled trial, where the same sarcopenic patients from Trial 1 were divided in two groups: a Control Group (CG, n = 15); and a Trained Group (TG, n = 22). RNA was extracted from serum samples for all the participants, and the expression of 6 lncRNA (PVT1, HOTAIR, MALAT1, NEAT1, GAS5, H19), selected from the literature, was quantified by RT-PCR and compared between the different groups. Statistical evaluation uncovered four lncRNAs with significantly distinct expression in Trial 1: PVT1 (LOG2FC = 1.194), GAS5 (LOG2FC = 0.8224), NEAT1 (LOG2FC = 1.497) and H19 (LOG2FC = −0.9958) and three lncRNA significantly different between TG and CG in Trial 2 (PVT1 (LOG2FC = −1.796), MALAT1 (LOG2FC = 2.834) and H19 (LOG2FC = 1.355). Among them, NEAT 1 stands aout as promissing diagnostic marker ans PVT1 and H19 may serve as both diagnosis and treatment monitoring, altough further validation in larger cohorts is needed to confirm these results
Decomposition of CH3NH2: Implications for CHx/NHy radical–radical reactions
No full textExperiments on methylamine () decomposition in shock tubes, flow reactors, and batch reactors have been re‐examined to improve the understanding of hydrocarbon/amine interactions and constrain rate constants for + reactions. In high‐temperature shock tube experiments, the rapid thermal dissociation of provides a fairly clean source of and radicals, allowing an assessment of reactions of with and NH. At the lower temperatures in batch and flow reactors, is mostly consumed by reaction with H to form + ; these results are useful in determining the fate of the radical. Interpretation of these data, along with flow reactor data for the /H system at lower temperature, indicates that at temperatures up to about 1400 K at atmospheric pressure and above 2000 K at 100 atm, the + reaction forms mainly methylamine. At sufficiently high temperature, H‐abstraction to form + NH and addition–elimination to form + H become competitive. The + NH reaction, with a rate constant close to collision frequency, forms + H, also leading into the hydrocarbon amine pool. Thus, methylamine can be expected to be an important intermediate in co‐combustion of natural gas and ammonia, and more work on the chemistry of is desirable
Unveiling the magnetic structure of BaFeO3-y: Shedding light on the elusive magnetic behavior
Get PDFThis work provides a comprehensive examination of the structural and magnetic properties of 6H-BaFeO2.96 over a wide temperature range (10 K < T < 300 K) using neutron and synchrotron X-ray diffraction. Additionally, the local oxidation state of iron is examined using electron energy loss spectroscopy. No structural changes that could indicate a charge-order transition are observed in spite of a reported possible charge disproportionation of Fe4+ into Fe(4+δ)+ and Fe(4-δ)+ phenomenon at low temperature. According to the magnetic characterization, BaFeO2.96 orders antiferromagnetically at TN=156 K. The application of external magnetic fields strongly influences the magnetic behavior; the transition temperature shifts to lower values with the applied magnetic field and the long-range magnetic order melts with an applied field of 14 T. The magnetocaloric effect clearly shows at TN a change from negative to positive magnetic entropy. The Rietveld refinement of the neutron powder diffraction data collected at 10 K, gives a magnetic ordering with propagation vector [0, 0, ½] and three magnetically distinct sites for the Fe atoms. This magnetic structure consists of ferromagnetic Fe-sheets perpendicular to the c-axis with the magnetic moments along the [110] direction coupled both ferromagnetic and antiferromagnetically along the c-axis. The magnetic moment values of the three Fe ions are very different evidencing a delicate equilibrium of competing magnetic interactions
Structure-preserving formulations for data-driven analysis of coupled multi-physics systems
Get PDFWe develop a novel methodology for data-driven simulation of coupled multi-physics systems. The result of the method is a learned numerical integrator of the coupled system dynamics. In order to preserve the fundamental physics of the coupled systems, and thus preserve the geometrical properties of the governing equations—even if they may be completely unknown—we impose a port-metriplectic structure on the system evolution, i.e., a combination of a symplectic evolution for the system energy with a gradient flow for the entropy of each system, which can be exchanged through predefined ports. The resulting method guarantees by construction the satisfaction of the laws of thermodynamics for open systems, leading to accurate predictions of the future states of their dynamics. Examples are given for systems of varying complexity, based on synthetic as well as experimental data
Numerical analysis of solidification of paraffin-type PCMs by using customary fixed-grid methods
Get PDFA numerical study is conducted to predict temperature measurements during the solidification of a commercial paraffin-type PCM in a vertical cylinder under T-history conditions. Two fixed-grid techniques are implemented: the enthalpy-porosity formulation and the Apparent Heat Capacity (AHC) method. As it is known, the first, originally devised for metals and alloys, raises questions about its applicability to other materials. Additionally, there may be uncertainties surrounding the assignment of internal parameters when representing the transitional “mushy” region. On the other side, there are limited publications that utilize the AHC method, and even fewer have addressed and compared both methods. Phase-change properties of the paraffin material are determined through the use of differential scanning calorimetry (DSC): phase change temperature range, latent heat, and specific heat capacity vs. temperature curve (). Results show that there is significant disagreement between measurements and simulation results for both methods. The enthalpy-porosity technique may not be entirely suitable for accurately modeling phase changes in paraffin-type PCM. Furthermore, while the AHC method can effectively predict the initial and final stages of solidification, it tends to struggle with accurately simulating the mushy zone. An interesting observation is that in the AHC method, the cooling rate is a critical factor influencing the accuracy of solidification simulations and results depend very much on the DSC curve introduced, determined under a constant cooling rate, which is indeed variable during the experimen
The emergence of resistance to the antiparasitic selamectin in Mycobacterium smegmatis is improbable and contingent on cell wall integrity
Get PDFTuberculosis remains the deadliest infectious disease of the 21st century. New antimicrobials are needed to improve treatment outcomes and enable therapy shortening. Drug repurposing is an alternative to the traditional drug discovery process. The avermectins are a family of macrocyclic lactones with anthelmintic activity active against Mycobacterium tuberculosis. However, their mode of action in mycobacteria remains unknown. In this study, we employed traditional mutant isolation approaches using Mycobacterium smegmatis, a non-pathogenic M. tuberculosis surrogate. We were only able to isolate mutants with decreased susceptibility to selamectin using the ∆nucS mutator M. smegmatis strain. This phenotype was caused by mutations in mps1 and mmpL11. Two of these mutants were used for a second experiment in which high-level selamectin-resistant mutants were isolated; however, specific mutations driving the phenotypic change to high-level resistance could not be identified. The susceptibility to selamectin in these mutants was restored to the basal level by subinhibitory concentrations of ethambutol. The selection of ethambutol resistance in a high-level selamectin-resistant mutant also resulted in multiple colonies becoming susceptible to selamectin again. These colonies carried mutations in embB, suggesting that the integrity of the cell envelope is a prerequisite for selamectin resistance. The absence of increased susceptibility to selamectin in an embB deletion strain demonstrated that the target of selamectin is not cytosolic. Our data show that the concurrence of specific multiple mutations and complete integrity of the mycobacterial envelope are necessary for selamectin resistance. Our studies provide first-time insights into the antimycobacterial mode of action of the antiparasitic avermectins