83,387 results on '"Aguilera, A"'
Search Results
2. "Beetles or Eagles?": Cultural Politics and the Comité Popular de Defensa Mexicana in Los Angeles, 1930-1936
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Aguilera, Andy Rafael
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- 2022
3. Multi-finger Manipulation via Trajectory Optimization with Differentiable Rolling and Geometric Constraints
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Yang, Fan, Power, Thomas, Marinovic, Sergio Aguilera, Iba, Soshi, Zarrin, Rana Soltani, and Berenson, Dmitry
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Computer Science - Robotics - Abstract
Parameterizing finger rolling and finger-object contacts in a differentiable manner is important for formulating dexterous manipulation as a trajectory optimization problem. In contrast to previous methods which often assume simplified geometries of the robot and object or do not explicitly model finger rolling, we propose a method to further extend the capabilities of dexterous manipulation by accounting for non-trivial geometries of both the robot and the object. By integrating the object's Signed Distance Field (SDF) with a sampling method, our method estimates contact and rolling-related variables and includes those in a trajectory optimization framework. This formulation naturally allows for the emergence of finger-rolling behaviors, enabling the robot to locally adjust the contact points. Our method is tested in a peg alignment task and a screwdriver turning task, where it outperforms the baselines in terms of achieving desired object configurations and avoiding dropping the object. We also successfully apply our method to a real-world screwdriver turning task, demonstrating its robustness to the sim2real gap.
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- 2024
4. Value-Enriched Population Synthesis: Integrating a Motivational Layer
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Aguilera, Alba, Albertí, Miquel, Osman, Nardine, and Curto, Georgina
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Computer Science - Multiagent Systems - Abstract
In recent years, computational improvements have allowed for more nuanced, data-driven and geographically explicit agent-based simulations. So far, simulations have struggled to adequately represent the attributes that motivate the actions of the agents. In fact, existing population synthesis frameworks generate agent profiles limited to socio-demographic attributes. In this paper, we introduce a novel value-enriched population synthesis framework that integrates a motivational layer with the traditional individual and household socio-demographic layers. Our research highlights the significance of extending the profile of agents in synthetic populations by incorporating data on values, ideologies, opinions and vital priorities, which motivate the agents' behaviour. This motivational layer can help us develop a more nuanced decision-making mechanism for the agents in social simulation settings. Our methodology integrates microdata and macrodata within different Bayesian network structures. This contribution allows to generate synthetic populations with integrated value systems that preserve the inherent socio-demographic distributions of the real population in any specific region.
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- 2024
5. Explosive neural networks via higher-order interactions in curved statistical manifolds
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Aguilera, Miguel, Morales, Pablo A., Rosas, Fernando E., and Shimazaki, Hideaki
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Condensed Matter - Disordered Systems and Neural Networks ,Condensed Matter - Statistical Mechanics ,Computer Science - Information Theory ,Nonlinear Sciences - Adaptation and Self-Organizing Systems ,Statistics - Machine Learning - Abstract
Higher-order interactions underlie complex phenomena in systems such as biological and artificial neural networks, but their study is challenging due to the lack of tractable standard models. By leveraging the maximum entropy principle in curved statistical manifolds, here we introduce curved neural networks as a class of prototypical models for studying higher-order phenomena. Through exact mean-field descriptions, we show that these curved neural networks implement a self-regulating annealing process that can accelerate memory retrieval, leading to explosive order-disorder phase transitions with multi-stability and hysteresis effects. Moreover, by analytically exploring their memory capacity using the replica trick near ferromagnetic and spin-glass phase boundaries, we demonstrate that these networks enhance memory capacity over the classical associative-memory networks. Overall, the proposed framework provides parsimonious models amenable to analytical study, revealing novel higher-order phenomena in complex network systems.
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- 2024
6. Delayed jet launching in binary neutron star mergers with realistic initial magnetic fields
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Aguilera-Miret, Ricard, Palenzuela, Carlos, Carrasco, Federico, Rosswog, Stephan, and Viganò, Daniele
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Astrophysics - High Energy Astrophysical Phenomena ,General Relativity and Quantum Cosmology - Abstract
We analyze a long-lived hyper-massive neutron star merger remnant (post-merger lifetime $>250$ ms) that has been obtained via large eddy simulations with a gradient subgrid-scale model. We find a clear helicoidal magnetic field structure that is governed by the toroidal component of the magnetic field. Although no jet emerges during the simulation time, we observe at late times a significant increase of the poloidal component of the magnetic field at all scales. We also compare with the results of several binary neutron star simulations with moderate resolution of $120$~m, that are evolved up to $50$~ms after the merger, which differ in terms of the initial topology and strength of the magnetic field. We find that the best choice is an isotropic small-scale magnetic field distribution that mimics the turbulent state that generically develops during the merger. This initial configuration reaches a closer agreement with our high-resolution simulation results than the purely dipolar large-scale fields that are commonly employed in these type of simulations. This provides a recipe to perform such simulations avoiding the computationally expensive grids required to faithfully capture the amplification of the magnetic field by Kelvin-Helmholtz instabilities., Comment: 13 pages, 11 figures
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- 2024
7. Re-description of Xyliphius barbatus (Siluriformes, Aspredinidae), with comments on osteology and distribution
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Terán, Guillermo E., Méndez-López, Alejandro, Benitez, Mauricio F., Serra, Wilson S., Bogan, Sergio, Aguilera, Gastón, and Pensoft Publishers
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Banjo catfish ,fossorial fishes ,La Plata River basin ,Morphology ,Osteology - Published
- 2024
8. Dynamical Mean-Field Theory of Self-Attention Neural Networks
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Poc-López, Ángel and Aguilera, Miguel
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Condensed Matter - Disordered Systems and Neural Networks ,Computer Science - Machine Learning - Abstract
Transformer-based models have demonstrated exceptional performance across diverse domains, becoming the state-of-the-art solution for addressing sequential machine learning problems. Even though we have a general understanding of the fundamental components in the transformer architecture, little is known about how they operate or what are their expected dynamics. Recently, there has been an increasing interest in exploring the relationship between attention mechanisms and Hopfield networks, promising to shed light on the statistical physics of transformer networks. However, to date, the dynamical regimes of transformer-like models have not been studied in depth. In this paper, we address this gap by using methods for the study of asymmetric Hopfield networks in nonequilibrium regimes --namely path integral methods over generating functionals, yielding dynamics governed by concurrent mean-field variables. Assuming 1-bit tokens and weights, we derive analytical approximations for the behavior of large self-attention neural networks coupled to a softmax output, which become exact in the large limit size. Our findings reveal nontrivial dynamical phenomena, including nonequilibrium phase transitions associated with chaotic bifurcations, even for very simple configurations with a few encoded features and a very short context window. Finally, we discuss the potential of our analytic approach to improve our understanding of the inner workings of transformer models, potentially reducing computational training costs and enhancing model interpretability.
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- 2024
9. DSig: Breaking the Barrier of Signatures in Data Centers
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Aguilera, Marcos K., Burgelin, Clément, Guerraoui, Rachid, Murat, Antoine, Xygkis, Athanasios, and Zablotchi, Igor
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Computer Science - Cryptography and Security ,Computer Science - Distributed, Parallel, and Cluster Computing - Abstract
Data centers increasingly host mutually distrustful users on shared infrastructure. A powerful tool to safeguard such users are digital signatures. Digital signatures have revolutionized Internet-scale applications, but current signatures are too slow for the growing genre of microsecond-scale systems in modern data centers. We propose DSig, the first digital signature system to achieve single-digit microsecond latency to sign, transmit, and verify signatures in data center systems. DSig is based on the observation that, in many data center applications, the signer of a message knows most of the time who will verify its signature. We introduce a new hybrid signature scheme that combines cheap single-use hash-based signatures verified in the foreground with traditional signatures pre-verified in the background. Compared to prior state-of-the-art signatures, DSig reduces signing time from 18.9 to 0.7 us and verification time from 35.6 to 5.1 us, while keeping signature transmission time below 2.5 us. Moreover, DSig achieves 2.5x higher signing throughput and 6.9x higher verification throughput than the state of the art. We use DSig to (a) bring auditability to two key-value stores (HERD and Redis) and a financial trading system (based on Liquibook) for 86% lower added latency than the state of the art, and (b) replace signatures in BFT broadcast and BFT replication, reducing their latency by 73% and 69%, respectively, Comment: To appear in the proceedings of OSDI '24. Authors listed in alphabetical order
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- 2024
10. Magnetocaloric effect for a $Q$-clock type system
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Aguilera, Michel, Pino-Alarcón, Sergio, Peña, Francisco J., Vogel, Eugenio E., and Vargas, Patricio
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Condensed Matter - Statistical Mechanics ,Quantum Physics - Abstract
In this work, we study the magnetocaloric effect applied to a magnetic working substance corresponding to a square lattice of spins with $Q$ possible orientations known as the ``$Q$-state clock model" where for $Q\geq 5$, the systems present the famous Berezinskii-Kosterlitz-Thouless phase (BKT). Thermodynamic quantities are obtained in exact form for a small lattice size of $L \times L$ with $L=3$ and by the mean-field approximation and Monte Carlo simulations for $Q$ pairs between 2 and 8 with $L = 3, 8, 16, 32$ with free boundary conditions, and magnetic fields varying between $B = 0$ and $1$ in natural units of the system. By obtaining the entropy, it is possible to quantify the caloric effect through an isothermal process in which the external magnetic field on the spin system is varied. In particular, we find the values of $Q$ that maximize the effect depending on the lattice size and the magnetic phase transitions related to maximizing the caloric phenomena. These indicate that in a small lattice (up to $\sim 7\times 7$), when $Q\geq 5$, the transition that maximizes the effect is related to ferromagnetic to BKT type. In contrast, transitioning from BKT to paramagnetic type increases the system's caloric response when we work with a larger lattice size.
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- 2024
11. Uniaxial strain effects on the Fermi surface and quantum mobility of the Dirac nodal-line semimetal ZrSiS
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Lorenz, J. P., Linnartz, J. F., Kool, A., van Delft, M. R., Guo, W., Aguilera, I., Singha, R., Schoop, L. M., Hussey, N. E., Wiedmann, S., and de Visser, A.
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Condensed Matter - Materials Science - Abstract
ZrSiS has been identified as an exemplary Dirac nodal-line semimetal, in which the Dirac band crossings extend along a closed loop in momentum space. Recently, the topology of the Fermi surface of ZrSiS was uncovered in great detail by quantum oscillation studies. For a magnetic field along the tetragonal $c$ axis, a rich frequency spectrum was observed stemming from the principal electron and hole pockets, and multiple magnetic breakdown orbits. In this work we use uniaxial strain as a tuning parameter for the Fermi surface and the low energy excitations. We measure the magnetoresistance of a single crystal under tensile (up to 0.34 %) and compressive (up to -0.28 %) strain exerted along the $a$ axis and in magnetic fields up to 30 T. We observe a systematic weakening of the peak structure in the Shubnikov-de Haas frequency spectrum upon changing from compressive to tensile strain. This effect may be explained by a decrease in the effective quantum mobility upon decreasing the $c/a$ ratio, which is corroborated by a concurrent increase in the Dingle temperature., Comment: 18 pages, 11 figures, to be published in Physical Review B
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- 2024
12. Dynamics of spatial phase coherence in a dissipative Bose-Hubbard atomic system
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Vatré, Rémy, Bouganne, Raphaël, Aguilera, Manel Bosch, Ghermaoui, Alexis, Beugnon, Jérôme, Lopes, Raphael, and Gerbier, Fabrice
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Condensed Matter - Quantum Gases - Abstract
We investigate the loss of spatial coherence of one-dimensional bosonic gases in optical lattices illuminated by a near-resonant excitation laser. Because the atoms recoil in a random direction after each spontaneous emission, the atomic momentum distribution progressively broadens. Equivalently, the spatial correlation function (the Fourier-conjugate quantity of the momentum distribution) progressively narrows down as more photons are scattered. Here we measure the correlation function of the matter field for fixed distances corresponding to nearest-neighbor (n-n) and next-nearest-neighbor (n-n-n) sites of the optical lattice as a function of time, hereafter called n-n and n-n-n correlators. For strongly interacting lattice gases, we find that the n-n correlator $C_1$ decays as a power-law at long times, $C_1\propto 1/t^{\alpha}$, in stark contrast with the exponential decay expected for independent particles. The power-law decay reflects a non-trivial dissipative many-body dynamics, where interactions change drastically the interplay between fluorescence destroying spatial coherence, and coherent tunnelling between neighboring sites restoring spatial coherence at short distances. The observed decay exponent $\alpha \approx 0.54(6) $ is in good agreement with the prediction $\alpha=1/2$ from a dissipative Bose-Hubbard model accounting for the fluorescence-induced decoherence. Furthermore, we find that the n-n correlator $C_1$ controls the n-n-n correlator $C_2$ through the relation $C_2 \approx C_1^2$, also in accordance with the dissipative Bose-Hubbard model., Comment: published in the special issue of Comptes Rendus Physique dedicated to Jean Dalibard's CNRS Gold Medal. Details of calculations, included as an appendix in the published article, are available in the ancillary file
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- 2024
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13. Quantum algorithms for N-1 security in power grids
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Neumann, Niels M. P., van der Linde, Stan, de Kok, Willem, Leijnse, Koen, Boschero, Juan, Aguilera, Esteban, Berg, Peter Elias-van den, Koppen, Vincent, Jaspers, Nikki, and Zwetsloot, Jelte
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Quantum Physics - Abstract
In recent years, the supply and demand of electricity has significantly increased. As a result, the interconnecting grid infrastructure has required (and will continue to require) further expansion, while allowing for rapid resolution of unforeseen failures. Energy grid operators strive for networks that satisfy different levels of security requirements. In the case of N-1 security for medium voltage networks, the goal is to ensure the continued provision of electricity in the event of a single-link failure. However, the process of determining if networks are N-1 secure is known to scale polynomially in the network size. This poses restrictions if we increase our demand of the network. In that case, more computationally hard cases will occur in practice and the computation time also increases significantly. In this work, we explore the potential of quantum computers to provide a more scalable solution. In particular, we consider gate-based quantum computing, quantum annealing, and photonic quantum computing.
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- 2024
14. The Pristine Inner Galaxy Survey (PIGS) IX. The largest detailed chemical analysis of very metal-poor stars in the Sagittarius dwarf galaxy
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Sestito, Federico, Vitali, Sara, Jofre, Paula, Venn, Kim A., Aguado, David S., Aguilera-Gómez, Claudia, Ardern-Arentsen, Anke, Silva, Danielle de Brito, Carlberg, Raymond, Eldridge, Camilla J. L., Gran, Felipe, Hill, Vanessa, Jablonka, Pascale, Kordopatis, Georges, Martin, Nicolas F., Matsuno, Tadafumi, Rusterucci, Samuel, Starkenburg, Else, and Viswanathan, Akshara
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
The most metal-poor stars provide valuable insights into the early chemical enrichment history of a system, carrying the chemical imprints of the first generations of supernovae. The most metal-poor region of the Sagittarius dwarf galaxy remains inadequately observed and characterised. To date, only $\sim4$ stars with [Fe/H]~$<-2.0$ have been chemically analysed with high-resolution spectroscopy. In this study, we present the most extensive chemical abundance analysis of 12 low-metallicity stars with metallicities down to [Fe/H]~$=-3.26$ and located in the main body of Sagittarius. These targets, selected from the Pristine Inner Galaxy Survey, were observed using the MIKE high-resolution spectrograph at the {\it Magellan-Clay} telescope, which allowed us to measure up to 17 chemical species. The chemical composition of these stars reflects the imprint of a variety of type~II supernovae (SNe~II). A combination of low- to intermediate-mass high-energy SNe and hypernovae ($\sim10-70\msun$) is required to account for the abundance patterns of the lighter elements up to the Fe-peak. The trend of the heavy elements suggests the involvement of compact binary merger events and fast-rotating (up to $\sim300\kms$) intermediate-mass to massive metal-poor stars ($\sim25-120\msun$) that are the sources of rapid and slow processes, respectively. Additionally, asymptotic giant branch stars contribute to a wide dispersion of [Ba/Mg] and [Ba/Eu]. The absence of an $\alpha-$knee in our data indicates that type Ia supernovae did not contribute in the very metal-poor region ([Fe/H]~$\leq-2.0$). However, they might have started to pollute the interstellar medium at [Fe/H]~$>-2.0$, given the relatively low [Co/Fe] in this metallicity region., Comment: Accepted for publication in A&A. New plot on [Eu/Mg]. Some refs updated
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- 2024
15. Efficient 6-dimensional phase space reconstruction from experimental measurements using generative machine learning
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Roussel, Ryan, Gonzalez-Aguilera, Juan Pablo, Edelen, Auralee, Wisniewski, Eric, Ody, Alex, Liu, Wanming, Kim, Young-Kee, and Power, John
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Physics - Accelerator Physics - Abstract
Next-generation accelerator concepts which hinge on the precise shaping of beam distributions, demand equally precise diagnostic methods capable of reconstructing beam distributions within 6-dimensional position-momentum spaces. However, the characterization of intricate features within 6-dimensional beam distributions using conventional diagnostic techniques necessitates hundreds of measurements, using many hours of valuable beam time. Novel phase space reconstruction techniques are needed to substantially reduce the number of measurements required to reconstruct detailed, high-dimensional beam features in order to resolve complex beam phenomena, and as feedback in precision beam shaping applications. In this study, we present a novel approach to reconstructing detailed 6-dimensional phase space distributions from experimental measurements using generative machine learning and differentiable beam dynamics simulations. We demonstrate that for a collection of synthetic beam distribution test cases that this approach can be used to resolve 6-dimensional phase space distributions using basic beam manipulations and as few as 20 2-dimensional measurements of the beam profile, without the need for prior data collection or model training. We also demonstrate an application of the reconstruction method in an experimental setting at the Argonne Wakefield Accelerator, where it is able to reconstruct the beam distribution and accurately predict previously unseen measurements 75x faster than previous methods.
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- 2024
16. FLEX: FLEXible Federated Learning Framework
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Herrera, Francisco, Jiménez-López, Daniel, Argente-Garrido, Alberto, Rodríguez-Barroso, Nuria, Zuheros, Cristina, Aguilera-Martos, Ignacio, Bello, Beatriz, García-Márquez, Mario, and Luzón, M. Victoria
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Computer Science - Cryptography and Security ,Computer Science - Artificial Intelligence - Abstract
In the realm of Artificial Intelligence (AI), the need for privacy and security in data processing has become paramount. As AI applications continue to expand, the collection and handling of sensitive data raise concerns about individual privacy protection. Federated Learning (FL) emerges as a promising solution to address these challenges by enabling decentralized model training on local devices, thus preserving data privacy. This paper introduces FLEX: a FLEXible Federated Learning Framework designed to provide maximum flexibility in FL research experiments. By offering customizable features for data distribution, privacy parameters, and communication strategies, FLEX empowers researchers to innovate and develop novel FL techniques. The framework also includes libraries for specific FL implementations including: (1) anomalies, (2) blockchain, (3) adversarial attacks and defences, (4) natural language processing and (5) decision trees, enhancing its versatility and applicability in various domains. Overall, FLEX represents a significant advancement in FL research, facilitating the development of robust and efficient FL applications., Comment: Submitted to Information Fusion
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- 2024
17. Stochastic modeling of Random Access Memories reset transitions
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Aguilera-Morillo, M Carmen, Aguilera, Ana M, Jiménez-Molinos, Francisco, and Roldán, Juan B
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Statistics - Methodology ,Computer Science - Emerging Technologies ,Mathematics - Statistics Theory - Abstract
Resistive Random Access Memories (RRAMs) are being studied by the industry and academia because it is widely accepted that they are promising candidates for the next generation of high density nonvolatile memories. Taking into account the stochastic nature of mechanisms behind resistive switching, a new technique based on the use of functional data analysis has been developed to accurately model resistive memory device characteristics. Functional principal component analysis (FPCA) based on Karhunen-Loeve expansion is applied to obtain an orthogonal decomposition of the reset process in terms of uncorrelated scalar random variables. Then, the device current has been accurately described making use of just one variable presenting a modeling approach that can be very attractive from the circuit simulation viewpoint. The new method allows a comprehensive description of the stochastic variability of these devices by introducing a probability distribution that allows the simulation of the main parameter that is employed for the model implementation. A rigorous description of the mathematical theory behind the technique is given and its application for a broad set of experimental measurements is explained.
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- 2024
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18. Multi-class classification of biomechanical data: A functional LDA approach based on multi-class penalized functional PLS
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Aguilera-Morillo, M Carmen and Aguilera, Ana M
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Statistics - Methodology ,Mathematics - Statistics Theory - Abstract
A functional linear discriminant analysis approach to classify a set of kinematic data (human movement curves of individuals performing different physical activities) is performed. Kinematic data, usually collected in linear acceleration or angular rotation format, can be identified with functions in a continuous domain (time, percentage of gait cycle, etc.). Since kinematic curves are measured in the same sample of individuals performing different activities, they are a clear example of functional data with repeated measures. On the other hand, the sample curves are observed with noise. Then, a roughness penalty might be necessary in order to provide a smooth estimation of the discriminant functions, which would make them more interpretable. Moreover, because of the infinite dimension of functional data, a reduction dimension technique should be considered. To solve these problems, we propose a multi-class approach for penalized functional partial least squares (FPLS) regression. Then linear discriminant analysis (LDA) will be performed on the estimated FPLS components. This methodology is motivated by two case studies. The first study considers the linear acceleration recorded every two seconds in 30 subjects, related to three different activities (walking, climbing stairs and down stairs). The second study works with the triaxial angular rotation, for each joint, in 51 children when they completed a cycle walking under three conditions (walking, carrying a backpack and pulling a trolley). A simulation study is also developed for comparing the performance of the proposed functional LDA with respect to the corresponding multivariate and non-penalized approaches.
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- 2024
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19. Linear-Phase-Type probability modelling of functional PCA with applications to resistive memories
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Ruiz-Castro, Juan E., Acal, Christian, Aguilera, Ana M., Aguilera-Morillo, M. Carmen, and Roldán, Juan B.
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Statistics - Methodology - Abstract
Functional principal component analysis based on Karhunen Loeve expansion allows to describe the stochastic evolution of the main characteristics associated to multiple systems and devices. Identifying the probability distribution of the principal component scores is fundamental to characterize the whole process. The aim of this work is to consider a family of statistical distributions that could be accurately adjusted to a previous transformation. Then, a new class of distributions, the linear-phase-type, is introduced to model the principal components. This class is studied in detail in order to prove, through the KL expansion, that certain linear transformations of the process at each time point are phase-type distributed. This way, the one-dimensional distributions of the process are in the same linear-phase-type class. Finally, an application to model the reset process associated with resistive memories is developed and explained.
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- 2024
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20. Homogeneity problem for basis expansion of functional data with applications to resistive memories
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Aguilera, Ana M, Acal, Christian, Aguilera-Morillo, M Carmen, Jiménez-Molinos, Francisco, and Roldán, Juan B.
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Statistics - Methodology - Abstract
The homogeneity problem for testing if more than two different samples come from the same population is considered for the case of functional data. The methodological results are motivated by the study of homogeneity of electronic devices fabricated by different materials and active layer thicknesses. In the case of normality distribution of the stochastic processes associated with each sample, this problem is known as Functional ANOVA problem and is reduced to test the equality of the mean group functions (FANOVA). The problem is that the current/voltage curves associated with Resistive Random Access Memories (RRAM) are not generated by a Gaussian process so that a different approach is necessary for testing homogeneity. To solve this problem two different parametric and nonparametric approaches based on basis expansion of the sample curves are proposed. The first consists of testing multivariate homogeneity tests on a vector of basis coefficients of the sample curves. The second is based on dimension reduction by using functional principal component analysis of the sample curves (FPCA) and testing multivariate homogeneity on a vector of principal components scores. Different approximation numerical techniques are employed to adapt the experimental data for the statistical study. An extensive simulation study is developed for analyzing the performance of both approaches in the parametric and non-parametric cases. Finally, the proposed methodologies are applied on three samples of experimental reset curves measured in three different RRAM technologies.
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- 2024
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21. The health benefits of reducing micro-heat islands: A 22-year analysis of the impact of urban temperature reduction on heat-related illnesses in California's major cities
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Lasky, Emma, Costello, Sadie, Ndovu, Allan, Aguilera, Rosana, Weiser, Sheri D, and Benmarhnia, Tarik
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Geomatic Engineering ,Engineering ,Clinical Research ,Climate Action ,Climate change ,Extreme heat events ,Health ,Heat related illness ,Urban ,Urban heat islands ,Environmental Sciences - Abstract
This study investigates the relationship between temporal changes in temperatures characterizing local urban heat islands (UHIs) and heat-related illnesses (HRIs) in seven major cities of California. UHIs, which are a phenomenon that arises in the presence of impervious surfaces or the lack of green spaces exacerbate the effects of extreme heat events, can be measured longitudinally using satellite products. The two objectives of this study were: (1) to identify temperature trends in local temperatures to characterize UHIs across zip code tabulation areas (ZCTAs) in the seven observed cities over a 22-year period and (2) to use propensity score and inverse probability weighting to achieve exchangeability between different types of ZCTAs and assess the difference in hospital admissions recorded as HRIs attributable to temporal changes in UHIs. We use monthly land surface temperature data derived from MODIS Terra imagery from the summer months (June-September) from 2000 to 2022. We categorized ZCTAs (into three groups) based on their monthly land surface temperature trends. Of the 216 ZCTAs included in this study, the summertime land surface temperature trends of 43 decreased, while 161 remained unchanged, and 12 increased. Los Angeles had the greatest number of decreased ZCTAs, San Diego and San Jose had the highest number of increased ZCTAs. To analyze the number of monthly HRI attributable to changes in UHI, we used inverse probability of treatment weighting to analyze the difference in HRI between the years of 2006 and 2017 which were two major extreme heat events over the entire State. We observed an average reduction of 3.2 (95 % CI: 0.5; 5.9) HRIs per month and per ZCTAs in decreased neighborhoods as compared to unchanged. This study emphasizes the importance of urban climate adaptation strategies to mitigate the intensity and prevalence of UHIs to reduce health risks related to heat.
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- 2024
22. Developing Messaging Content for a Physical Activity Smartphone App Tailored to Low-Income Patients: User-Centered Design and Crowdsourcing Approach
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Pathak, Laura Elizabeth, Aguilera, Adrian, Williams, Joseph Jay, Lyles, Courtney Rees, Hernandez-Ramos, Rosa, Miramontes, Jose, Cemballi, Anupama Gunshekar, and Figueroa, Caroline Astrid
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Information technology ,T58.5-58.64 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundText messaging interventions can be an effective and efficient way to improve health behavioral changes. However, most texting interventions are neither tested nor designed with diverse end users, which could reduce their impact, and there is limited evidence regarding the optimal design methodology of health text messages tailored to low-income, low–health literacy populations and non-English speakers. ObjectiveThis study aims to combine participant feedback, crowdsourced data, and researcher expertise to develop motivational text messages in English and Spanish that will be used in a smartphone app–based texting intervention that seeks to encourage physical activity in low-income minority patients with diabetes diagnoses and depression symptoms. MethodsThe design process consisted of 5 phases and was iterative in nature, given that the findings from each step informed the subsequent steps. First, we designed messages to increase physical activity based on the behavior change theory and knowledge from the available evidence. Second, using user-centered design methods, we refined these messages after a card sorting task and semistructured interviews (N=10) and evaluated their likeability during a usability testing phase of the app prototype (N=8). Third, the messages were tested by English- and Spanish-speaking participants on the Amazon Mechanical Turk (MTurk) crowdsourcing platform (N=134). Participants on MTurk were asked to categorize the messages into overarching theoretical categories based on the capability, opportunity, motivation, and behavior framework. Finally, each coauthor rated the messages for their overall quality from 1 to 5. All messages were written at a sixth-grade or lower reading level and culturally adapted and translated into neutral Spanish by bilingual research staff. ResultsA total of 200 messages were iteratively refined according to the feedback from target users gathered through user-centered design methods, crowdsourced results of a categorization test, and an expert review. User feedback was leveraged to discard unappealing messages and edit the thematic aspects of messages that did not resonate well with the target users. Overall, 54 messages were sorted into the correct theoretical categories at least 50% of the time in the MTurk categorization tasks and were rated 3.5 or higher by the research team members. These were included in the final text message bank, resulting in 18 messages per motivational category. ConclusionsBy using an iterative process of expert opinion, feedback from participants that were reflective of our target study population, crowdsourcing, and feedback from the research team, we were able to acquire valuable inputs for the design of motivational text messages developed in English and Spanish with a low literacy level to increase physical activity. We describe the design considerations and lessons learned for the text messaging development process and provide a novel, integrative framework for future developers of health text messaging interventions.
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- 2021
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23. Conducting Internet-Based Visits for Onboarding Populations With Limited Digital Literacy to an mHealth Intervention: Development of a Patient-Centered Approach
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Hernandez-Ramos, Rosa, Aguilera, Adrian, Garcia, Faviola, Miramontes-Gomez, Jose, Pathak, Laura Elizabeth, Figueroa, Caroline Astrid, and Lyles, Courtney Rees
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Medicine - Abstract
BackgroundThe COVID-19 pandemic has propelled patient-facing research to shift to digital and telehealth strategies. If these strategies are not adapted for minority patients of lower socioeconomic status, health inequality will further increase. Patient-centered models of care can successfully improve access and experience for minority patients. ObjectiveThis study aims to present the development process and preliminary acceptability of altering in-person onboarding procedures into internet-based, remote procedures for a mobile health (mHealth) intervention in a population with limited digital literacy. MethodsWe actively recruited safety-net patients (English- and Spanish-speaking adults with diabetes and depression who were receiving care at a public health care delivery system in San Francisco, United States) into a randomized controlled trial of text messaging support for physical activity. Because of the COVID-19 pandemic, we modified the in-person recruitment and onboarding procedures to internet-based, remote processes with human support. We conducted a preliminary evaluation of how the composition of the recruited cohort might have changed from the pre–COVID-19 period to the COVID-19 enrollment period. First, we analyzed the digital profiles of patients (n=32) who had participated in previous in-person onboarding sessions prior to the COVID-19 pandemic. Next, we documented all changes made to our onboarding processes to account for remote recruitment, especially those needed to support patients who were not very familiar with downloading apps onto their mobile phones on their own. Finally, we used the new study procedures to recruit patients (n=11) during the COVID-19 social distancing period. These patients were also asked about their experience enrolling into a fully digitized mHealth intervention. ResultsRecruitment across both pre–COVID-19 and COVID-19 periods (N=43) demonstrated relatively high rates of smartphone ownership but lower self-reported digital literacy, with 32.6% (14/43) of all patients reporting they needed help with using their smartphone and installing apps. Significant changes were made to the onboarding procedures, including facilitating app download via Zoom video call and/or a standard phone call and implementing brief, one-on-one staff-patient interactions to provide technical assistance personalized to each patient’s digital literacy skills. Comparing recruitment during pre–COVID-19 and COVID-19 periods, the proportion of patients with digital literacy barriers reduced from 34.4% (11/32) in the pre–COVID-19 cohort to 27.3% (3/11) in the COVID-19 cohort. Differences in digital literacy scores between both cohorts were not significant (P=.49). ConclusionsPatients of lower socioeconomic status have high interest in using digital platforms to manage their health, but they may require additional upfront human support to gain access. One-on-one staff-patient partnerships allowed us to provide unique technical assistance personalized to each patient’s digital literacy skills, with simple strategies to troubleshoot patient barriers upfront. These additional remote onboarding strategies can mitigate but not eliminate digital barriers for patients without extensive technology experience. Trial RegistrationClinicaltrials.gov NCT0349025, https://clinicaltrials.gov/ct2/show/NCT03490253
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- 2021
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24. CXCL12+ dermal fibroblasts promote neutrophil recruitment and host defense by recognition of IL-17
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Cavagnero, Kellen J, Li, Fengwu, Dokoshi, Tatsuya, Nakatsuji, Teruaki, O’Neill, Alan M, Aguilera, Carlos, Liu, Edward, Shia, Michael, Osuoji, Olive, Hata, Tissa, and Gallo, Richard L
- Subjects
Biomedical and Clinical Sciences ,Infectious Diseases ,Inflammatory and immune system ,Mice ,Animals ,Humans ,Interleukin-17 ,Neutrophil Infiltration ,Staphylococcus aureus ,Skin ,Fibroblasts ,Chemokine CXCL12 ,Medical and Health Sciences ,Immunology ,Biomedical and clinical sciences ,Health sciences - Abstract
The skin provides an essential barrier for host defense through rapid action of multiple resident and recruited cell types, but the complex communication network governing these processes is incompletely understood. To define these cell-cell interactions more clearly, we performed an unbiased network analysis of mouse skin during invasive S. aureus infection and revealed a dominant role for CXCL12+ fibroblast subsets in neutrophil communication. These subsets predominantly reside in the reticular dermis, express adipocyte lineage markers, detect IL-17 and TNFα, and promote robust neutrophil recruitment through NFKBIZ-dependent release of CXCR2 ligands and CXCL12. Targeted deletion of Il17ra in mouse fibroblasts resulted in greatly reduced neutrophil recruitment and increased infection by S. aureus. Analogous human CXCL12+ fibroblast subsets abundantly express neutrophil chemotactic factors in psoriatic skin that are subsequently decreased upon therapeutic targeting of IL-17. These findings show that CXCL12+ dermal immune acting fibroblast subsets play a critical role in cutaneous neutrophil recruitment and host defense.
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- 2024
25. Can Poverty Be Reduced by Acting on Discrimination? An Agent-based Model for Policy Making
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Aguilera, Alba, Montes, Nieves, Curto, Georgina, Sierra, Carles, and Osman, Nardine
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Computer Science - Multiagent Systems ,Computer Science - Artificial Intelligence - Abstract
In the last decades, there has been a deceleration in the rates of poverty reduction, suggesting that traditional redistributive approaches to poverty mitigation could be losing effectiveness, and alternative insights to advance the number one UN Sustainable Development Goal are required. The criminalization of poor people has been denounced by several NGOs, and an increasing number of voices suggest that discrimination against the poor (a phenomenon known as \emph{aporophobia}) could be an impediment to mitigating poverty. In this paper, we present the novel Aporophobia Agent-Based Model (AABM) to provide evidence of the correlation between aporophobia and poverty computationally. We present our use case built with real-world demographic data and poverty-mitigation public policies (either enforced or under parliamentary discussion) for the city of Barcelona. We classify policies as discriminatory or non-discriminatory against the poor, with the support of specialized NGOs, and we observe the results in the AABM in terms of the impact on wealth inequality. The simulation provides evidence of the relationship between aporophobia and the increase of wealth inequality levels, paving the way for a new generation of poverty reduction policies that act on discrimination and tackle poverty as a societal problem (not only a problem of the poor).
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- 2024
26. Four-Dimensional Phase-Space Reconstruction of Flat and Magnetized Beams Using Neural Networks and Differentiable Simulations
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Kim, Seongyeol, Gonzalez-Aguilera, Juan Pablo, Piot, Philippe, Chen, Gongxiaohui, Doran, Scott, Kim, Young-Kee, Liu, Wanming, Whiteford, Charles, Wisniewski, Eric, Edelen, Auralee, Roussel, Ryan, and Power, John
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Physics - Accelerator Physics - Abstract
Beams with cross-plane coupling or extreme asymmetries between the two transverse phase spaces are often encountered in particle accelerators. Flat beams with large transverse-emittance ratios are critical for future linear colliders. Similarly, magnetized beams with significant cross-plane coupling are expected to enhance the performance of electron cooling in hadron beams. Preparing these beams requires precise control and characterization of the four-dimensional transverse phase space. In this study, we employ generative phase space reconstruction (GPSR) techniques to rapidly characterize magnetized and flat-beam phase-space distributions using a conventional quadrupole-scan method. The reconstruction technique is experimentally demonstrated on an electron beam produced at the Argonne Wakefield Accelerator and successfully benchmarked against conventional diagnostics techniques. Specifically, we show that predicted beam parameters from the reconstructed phase-space distributions (e.g. as magnetization and flat beam emittances) are in excellent agreement with those measured from the conventional diagnostic methods.
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- 2024
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27. Video-Based Autism Detection with Deep Learning
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Serna-Aguilera, M., Nguyen, X. B., Singh, A., Rockers, L., Park, S., Neely, L., Seo, H., and Luu, K.
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Computer Science - Computer Vision and Pattern Recognition - Abstract
Individuals with Autism Spectrum Disorder (ASD) often experience challenges in health, communication, and sensory processing; therefore, early diagnosis is necessary for proper treatment and care. In this work, we consider the problem of detecting or classifying ASD children to aid medical professionals in early diagnosis. We develop a deep learning model that analyzes video clips of children reacting to sensory stimuli, with the intent of capturing key differences in reactions and behavior between ASD and non-ASD participants. Unlike many recent studies in ASD classification with MRI data, which require expensive specialized equipment, our method utilizes a powerful but relatively affordable GPU, a standard computer setup, and a video camera for inference. Results show that our model effectively generalizes and understands key differences in the distinct movements of the children. It is noteworthy that our model exhibits successful classification performance despite the limited amount of data for a deep learning problem and limited temporal information available for learning, even with the motion artifacts., Comment: Poster Abstract. Accepted into 2024 IEEE Green Technologies Conference
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- 2024
28. The Logic of Correct Models
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Aguilera, Juan Pablo and Pakhomov, Fedor
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Mathematics - Logic ,03B45, 03E99 - Abstract
For each $n\in\mathbb{N}$, let $[n]\phi$ mean "the sentence $\phi$ is true in all $\Sigma_{n+1}$-correct transitive sets." Assuming G\"odel's axiom $V = L$, we prove the following graded variant of Solovay's completeness theorem: the set of formulas valid under this interpretation is precisely the set of theorems of the linear provability logic GLP.3. We also show that this result is not provable in ZFC, so the hypothesis V = L cannot be removed. As part of the proof, we derive (in ZFC) the following purely modal-logical results which are of independent interest: the logic GLP.3 coincides with the logic of closed substitutions of GLP, and is the maximal non-degenerate, normal extension of GLP., Comment: 20 pages, 4 figures
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- 2024
29. Non-equilibrium theory of the linear viscoelasticity of glass and gel forming liquids
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Peredo-Ortiz, R., Joaquín-Jaime, O., López-Flores, L., Medina-Noyola, M., and Elizondo-Aguilera, L. F.
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Condensed Matter - Soft Condensed Matter ,Condensed Matter - Materials Science ,Physics - Applied Physics - Abstract
We propose a first-principles theoretical approach for the description of the aging of the linear viscoelastic properties of a colloidal liquid after a sudden quench into a dynamically arrested (glass or gel) state. Specifically, we couple a general expression for the time-evolving shear-stress relaxation function $\eta(\tau;t)$ (whose $\tau$-integral is the instantaneous viscosity $\eta(t)$), written in terms of the non-equilibrium structure factor $S(k;t)$ and intermediate scattering function $F(k,\tau;t)$, with the equations that determine $S(k;t)$ and $F(k,\tau;t)$, provided by the non-equilibrium self-consistent generalized Langevin equation (NE-SCGLE) theory. In this manner, we obtain a closed theoretical scheme that directly connects inter-particle forces with experimentally accessible rheological properties of non-equilibrium amorphous states of matter. The predictive capability of the resulting theoretical formalism is illustrated here with its concrete application to the Weeks-Chandler-Andersen (WCA) model of a soft-sphere fluid.
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- 2024
30. Functional ANOVA approaches for detecting changes in air pollution during the COVID-19 pandemic
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Acal, Christian, Aguilera, Ana M., Sarra, Annalina, Evangelista, Adelia, Di Battista, Tonio, and Palermi, Sergio
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Statistics - Applications ,Mathematics - Statistics Theory - Abstract
Faced with novel coronavirus outbreak, the most hard-hit countries adopted a lockdown strategy to contrast the spread of virus. Many studies have already documented that the COVID-19 control actions have resulted in improved air quality locally and around the world. Following these lines of research, we focus on air quality changes in the urban territory of Chieti-Pescara (Central Italy), identified as an area of criticality in terms of air pollution. Concentrations of NO2, PM10, PM2.5 and benzene are used to evaluate air pollution changes in this Region. Data were measured by several monitoring stations over two specific periods: from 1st February to 10 th March 2020 (before lockdown period) and from 11st March 2020 to 18 th April 2020 (during lockdown period). The impact of lockdown on air quality is assessed through functional data analysis. Our work makes an important contribution to the analysis of variance for functional data (FANOVA). Specifically, a novel approach based on multivariate functional principal component analysis is introduced to tackle the multivariate FANOVA problem for independent measures, which is reduced to test multivariate homogeneity on the vectors of the most explicative principal components scores. Results of the present study suggest that the level of each pollutant changed during the confinement. Additionally, the differences in the mean functions of all pollutants according to the location and type of monitoring stations (background vs traffic), are ascribable to the PM10 and benzene concentrations for pre-lockdown and during-lockdown tenure, respectively. FANOVA has proven to be beneficial to monitoring the evolution of air quality in both periods of time. This can help environmental protection agencies in drawing a more holistic picture of air quality status in the area of interest.
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- 2024
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31. logitFD: an R package for functional principal component logit regression
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Escabias, Manuel, Aguilera, Ana M., and Acal, Christian
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Statistics - Methodology ,Mathematics - Statistics Theory - Abstract
The functional logit regression model was proposed by Escabias et al. (2004) with the objective of modeling a scalar binary response variable from a functional predictor. The model estimation proposed in that case was performed in a subspace of L2(T) of squared integrable functions of finite dimension, generated by a finite set of basis functions. For that estimation it was assumed that the curves of the functional predictor and the functional parameter of the model belong to the same finite subspace. The estimation so obtained was affected by high multicollinearity problems and the solution given to these problems was based on different functional principal component analysis. The logitFD package introduced here provides a toolbox for the fit of these models by implementing the different proposed solutions and by generalizing the model proposed in 2004 to the case of several functional and non-functional predictors. The performance of the functions is illustrated by using data sets of functional data included in the fda.usc package from R-CRAN.
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- 2024
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32. Basis expansion approaches for functional analysis of variance with repeated measures
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Acal, Christian and Aguilera, Ana M.
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Statistics - Methodology ,Mathematics - Statistics Theory - Abstract
The methodological contribution in this paper is motivated by biomechanical studies where data characterizing human movement are waveform curves representing joint measures such as flexion angles, velocity, acceleration, and so on. In many cases the aim consists of detecting differences in gait patterns when several independent samples of subjects walk or run under different conditions (repeated measures). Classic kinematic studies often analyse discrete summaries of the sample curves discarding important information and providing biased results. As the sample data are obviously curves, a Functional Data Analysis approach is proposed to solve the problem of testing the equality of the mean curves of a functional variable observed on several independent groups under different treatments or time periods. A novel approach for Functional Analysis of Variance (FANOVA) for repeated measures that takes into account the complete curves is introduced. By assuming a basis expansion for each sample curve, two-way FANOVA problem is reduced to Multivariate ANOVA for the multivariate response of basis coefficients. Then, two different approaches for MANOVA with repeated measures are considered. Besides, an extensive simulation study is developed to check their performance. Finally, two applications with gait data are developed.
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- 2024
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33. Memristor variability and stochastic physical properties modeling from a multivariate time series approach
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Alonso, Francisco J., Maldonado, David, Aguilera, Ana M., and Roldán, Juan B.
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
A powerful time series analysis modeling technique is presented to describe cycle-to-cycle variability in memristors. These devices show variability linked to the inherent stochasticity of device operation and it needs to be accurately modeled to build compact models for circuit simulation and design purposes. A new multivariate approach is proposed for the reset and set voltages that accurately describes the statistical data structure of a resistive switching series. Experimental data were measured from advanced hafnium oxide based devices. The models reproduce the experiments correctly and a comparison of the multivariate and univariate approaches is shown for comparison.
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- 2024
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34. Phase-type distributions for studying variability in resistive memories
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Acal, Christian, Ruiz-Castro, Juan E., Aguilera, Ana M., Jiménez-Molinos, Francisco, and Roldán, Juan B.
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
A new statistical approach has been developed to analyze Resistive Random Access Memory (RRAM) variability. The stochastic nature of the physical processes behind the operation of resistive memories makes variability one of the key issues to solve from the industrial viewpoint of these new devices. The statistical features of variability have been usually studied making use of Weibull distribution. However, this probability distribution does not work correctly for some resistive memories, in particular for those based on the Ni/HfO2/Si structure that has been employed in this work. A completely new approach based on phase-type modeling is proposed in this paper to characterize the randomness of resistive memories operation. An in-depth comparison with experimental results shows that the fitted phase-type distribution works better than the Weibull distribution and also helps to understand the physics of the resistive memories.
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- 2024
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35. Evaluation of Zadoff-Chu, Kasami and Chirp based encoding schemes for Acoustic Local Positioning Systems
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Murano, Santiago, Perez-Rubio, Carmen, Gualda, David, Alvarez, Fernando J., Aguilera, Teodoro, and de Marziani, Carlos
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Electrical Engineering and Systems Science - Signal Processing - Abstract
The task of determining the physical coordinates of a target in indoor environments is still a key factor for many applications including people and robot navigation, user tracking, location-based advertising, augmented reality, gaming, emergency response or ambient assisted living environments. Among the different possibilities for indoor positioning, Acoustic Local Positioning Systems (ALPS) have the potential for centimeter level positioning accuracy with coverage distances up to tens of meters. In addition, acoustic transducers are small, low cost and reliable thanks to the room constrained propagation of these mechanical waves. Waveform design (coding and modulation) is usually incorporated into these systems to facilitate the detection of the transmitted signals at the receiver. The aperiodic correlation properties of the emitted signals have a large impact on how the ALPS cope with common impairment factors such as multipath propagation, multiple access interference, Doppler shifting, near-far effect or ambient noise. This work analyzes three of the most promising families of codes found in the literature for ALPS: Kasami codes, Zadoff-Chu and Orthogonal Chirp signals. The performance of these codes is evaluated in terms of time of arrival accuracy and characterized by means of model simulation under realistic conditions and by means of experimental tests in controlled environments. The results derived from this study can be of interest for other applications based on spreading sequences, such as underwater acoustic systems, ultrasonic imaging or even Code Division Multiple Access (CDMA) communications systems.
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- 2024
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36. Multipath Compensation Algorithm for TDMA-Based Ultrasonic Local Positioning Systems
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Aguilera, Teodoro, Alvarez, Fernando J., Gualda, David, Villadangos, Jose M., Hernandez, Alvaro, and Urena, Jesus
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Electrical Engineering and Systems Science - Signal Processing - Abstract
This paper proposes a multipath compensation algorithm (MCA) to enhance the performance of an ultrasonic local positioning system under adverse multipath conditions. The proposed algorithm is based on the accurate estimation of the environment impulse response from which the corresponding line of sight for each channel is obtained. Experimental results in two different environments and with different conditions have been conducted in order to evaluate the performance of this proposal. In both environments, results confirm the expected improvements, even under severe multipath conditions where positioning errors have been reduced from 44 to 9 cm for the 95% of the measurements.
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- 2024
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37. Acoustic Local Positioning With Encoded Emission Beacons
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Urena, Jesus, Hernandez, Alvaro, Garcia, Juan Jesus, Villadangos, Jose Manuel, Perez, Maria del Carmen, Gualda, David, Alvarez, Fernando J., and Aguilera, Teodoro
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Electrical Engineering and Systems Science - Signal Processing ,Computer Science - Hardware Architecture ,Computer Science - Sound ,Electrical Engineering and Systems Science - Audio and Speech Processing - Abstract
Acoustic local positioning systems (ALPSs) are an interesting alternative for indoor positioning due to certain advantages over other approaches, including their relatively high accuracy, low cost, and room-level signal propagation. Centimeter-level or fine-grained indoor positioning can be an asset for robot navigation, guiding a person to, for instance, a particular piece in a museum or to a specific product in a shop, targeted advertising, or augmented reality. In airborne system applications, acoustic positioning can be based on using opportunistic signals or sounds produced by the person or object to be located (e.g., noise from appliances or the speech from a speaker) or from encoded emission beacons (or anchors) specifically designed for this purpose. This work presents a review of the different challenges that designers of systems based on encoded emission beacons must address in order to achieve suitable performance. At low-level processing, the waveform design (coding and modulation) and the processing of the received signal are key factors to address such drawbacks as multipath propagation, multiple-access interference, nearfar effect, or Doppler shifting. With regards to high-level system design, the issues to be addressed are related to the distribution of beacons, ease of deployment, and calibration and positioning algorithms, including the possible fusion of information. Apart from theoretical discussions, this work also includes the description of an ALPS that was implemented, installed in a large area and tested for mobile robot navigation. In addition to practical interest for real applications, airborne ALPSs can also be used as an excellent platform to test complex algorithms, which can be subsequently adapted for other positioning systems, such as underwater acoustic systems or ultrawideband radiofrequency (UWB RF) systems.
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- 2024
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38. From equilibrium to non-equilibrium statistical mechanics of liquids
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Joaquín-Jaime, O., Peredo-Ortiz, R., Medina-Noyola, M., and Elizondo-Aguilera, L. F.
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Condensed Matter - Statistical Mechanics ,Condensed Matter - Soft Condensed Matter - Abstract
Relevant and fundamental concepts of the statistical mechanical theory of classical liquids are ordinarily introduced in the context of the description of thermodynamic equilibrium states. This makes explicit reference to probability distribution functions of \emph{equilibrium} statistical ensembles (canonical, microcanonical, ...) in the derivation of general and fundamental relations between inter-particle interactions and measurable macroscopic properties of a given system. This includes, for instance, expressing the internal energy and the pressure as functionals of the radial distribution function, or writing transport coefficients (diffusion constant, linear viscosity, ...) in terms of integral relations involving both, static and dynamic auto-correlation functions (density-density, stress-stress, ...). Most commonly, however, matter is not in thermodynamic equilibrium, and this calls for the extension of these relations to out-of-equilibrium conditions with the aim of understanding, for example, the time-dependent transient states during the process of equilibration, or the aging of glass- and gel-forming liquids during the formation of non-equilibrium amorphous solid states. In this work we address this issue from both, a general perspective and an illustrative concrete application focused on the first principles description of rheological and viscoelastic properties of glass- and gel-forming liquids.
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- 2024
39. Modelling physical activity profiles in COPD patients: a fully functional approach to variable domain functional regression models
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Hernandez-Amaro, Pavel, Durban, Maria, Aguilera-Morillo, M. Carmen, Gonzalez, Cristobal Esteban, and Arostegui, Inmaculada
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Statistics - Methodology ,Mathematics - Statistics Theory ,Statistics - Applications - Abstract
Physical activity plays a significant role in the well-being of individuals with Chronic obstructive Pulmonary Disease (COPD). Specifically, it has been directly associated with changes in hospitalization rates for these patients. However, previous investigations have primarily been conducted in a cross-sectional or longitudinal manner and have not considered a continuous perspective. Using the telEPOC program we use telemonitoring data to analyze the impact of physical activity adopting a functional data approach. However, Traditional functional data methods, including functional regression models, typically assume a consistent data domain. However, the data in the telEPOC program exhibits variable domains, presenting a challenge since the majority of functional data methods, are based on the fact that data are observed in the same domain. To address this challenge, we introduce a novel fully functional methodology tailored to variable domain functional data, eliminating the need for data alignment, which can be computationally taxing. Although models designed for variable domain data are relatively scarce and may have inherent limitations in their estimation methods, our approach circumvents these issues. We substantiate the effectiveness of our methodology through a simulation study, comparing our results with those obtained using established methodologies. Finally, we apply our methodology to analyze the impact of physical activity in COPD patients using the telEPOC program's data. Software for our method is available in the form of R code on request at \url{https://github.com/Pavel-Hernadez-Amaro/V.D.F.R.M-new-estimation-approach.git}.
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- 2024
40. Exploring duality symmetries, multicriticality and RG flows at $c = 2$
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Damia, Jeremias Aguilera, Galati, Giovanni, Hulik, Ondrej, and Mancani, Salvo
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High Energy Physics - Theory - Abstract
In this work, we study the realization of non-invertible duality symmetries along the toroidal branch of the $c=2$ conformal manifold. A systematic procedure to construct symmetry defects is implemented to show that all Rational Conformal Field Theories along this branch enjoy duality symmetries. Furthermore, we delve into an in-depth analysis of two representative cases of multicritical theories, were the toroidal branch meets various orbifold branches. For these particular examples, the categorical data and the defect Hilbert spaces associated to the duality symmetries are obtained by resorting to modular covariance. Finally, we study the interplay between these novel symmetries and the various exactly marginal and relevant deformations, including some representative examples of Renormalization Group flows where the infrared is constrained by the non-invertible symmetries and their anomalies., Comment: 45 pages + appendices. Minor improvements, matches journal version
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- 2024
41. A Text Messaging Intervention for Coping With Social Distancing During COVID-19 (StayWell at Home): Protocol for a Randomized Controlled Trial
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Figueroa, Caroline Astrid, Hernandez-Ramos, Rosa, Boone, Claire Elizabeth, Gómez-Pathak, Laura, Yip, Vivian, Luo, Tiffany, Sierra, Valentín, Xu, Jing, Chakraborty, Bibhas, Darrow, Sabrina, and Aguilera, Adrian
- Subjects
Medicine ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
BackgroundSocial distancing is a crucial intervention to slow down person-to-person transmission of COVID-19. However, social distancing has negative consequences, including increases in depression and anxiety. Digital interventions, such as text messaging, can provide accessible support on a population-wide scale. We developed text messages in English and Spanish to help individuals manage their depressive mood and anxiety during the COVID-19 pandemic. ObjectiveIn a two-arm randomized controlled trial, we aim to examine the effect of our 60-day text messaging intervention. Additionally, we aim to assess whether the use of machine learning to adapt the messaging frequency and content improves the effectiveness of the intervention. Finally, we will examine the differences in daily mood ratings between the message categories and time windows. MethodsThe messages were designed within two different categories: behavioral activation and coping skills. Participants will be randomized into (1) a random messaging arm, where message category and timing will be chosen with equal probabilities, and (2) a reinforcement learning arm, with a learned decision mechanism for choosing the messages. Participants in both arms will receive one message per day within three different time windows and will be asked to provide their mood rating 3 hours later. We will compare self-reported daily mood ratings; self-reported depression, using the 8-item Patient Health Questionnaire; and self-reported anxiety, using the 7-item Generalized Anxiety Disorder scale at baseline and at intervention completion. ResultsThe Committee for the Protection of Human Subjects at the University of California Berkeley approved this study in April 2020 (No. 2020-04-13162). Data collection began in April 2020 and will run to April 2021. As of August 24, 2020, we have enrolled 229 participants. We plan to submit manuscripts describing the main results of the trial and results from the microrandomized trial for publication in peer-reviewed journals and for presentations at national and international scientific meetings. ConclusionsResults will contribute to our knowledge of effective psychological tools to alleviate the negative effects of social distancing and the benefit of using machine learning to personalize digital mental health interventions. Trial RegistrationClinicalTrials.gov NCT04473599; https://clinicaltrials.gov/ct2/show/NCT04473599 International Registered Report Identifier (IRRID)DERR1-10.2196/23592
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- 2021
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42. Mauricio Núñez Rodríguez, Silencios y recepciones: la novela de José Martí
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Aguilera, Osmar Sánchez
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- 2024
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43. Victoria Aranda Arribas, Las 'Novelas ejemplares' en el cine y la televisión
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Aguilera, Tania Padilla
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- 2024
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44. Winter mortality of freshwater fish associated with parasitic infection /Mortalidad invernal de peces de agua dulce asociada a infeccion parasitaria
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Hernandez, D.R., Aichino, D.R., Santinon, J.J., Ruiz Diaz, F.J., Aguilera, J.N., Roux, J.P., and Sanchez, S.
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- 2024
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45. Integrated insights into the cytological, histochemical, and cell wall composition features of Espinosa nothofagi (Hymenoptera) gall tissues: implications for functionality
- Author
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Guedes, Lubia María, Aguilera, Narciso, Kuster, Vinícius Coelho, da Silva Carneiro, Renê Gonçalves, and de Oliveira, Denis Coelho
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- 2024
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46. Dietary-Based Diabetes Risk Score and breast cancer: a prospective evaluation in the SUN project
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Aguilera-Buenosvinos, Inmaculada, Martínez-González, Miguel A., Romanos-Nanclares, Andrea, Sánchez-Bayona, Rodrigo, de Andrea, Carlos E., Domínguez, Ligia J., and Toledo, Estefania
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- 2024
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47. Assessment for acceleration and transformation of chronic lymphocytic leukemia/small lymphocytic lymphoma using histologic and immunohistochemical features: a case series
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Moore, Margaret E., Aguilera, Nadine S., Obiorah, Ifeyinwa, Williams, Eli, and Courville, Elizabeth
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- 2024
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48. Nationalist sentiments and the multinational enterprise: insights from organizational sociology
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Edman, Jesper, Cuypers, Ilya R. P., Ertug, Gokhan, and Aguilera, Ruth V.
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- 2024
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49. Standardization of Point-of-Care-Ultrasonography in Critical Care: Enhancing Quality and Efficiency
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Garcia, Yunuen Aguilera, Han, Jeong, Vidovic, Zora, and Luis Díaz-Gómez, José
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- 2024
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50. Antimicrobial resistance, virulence genes, and ESBL (Extended Spectrum Beta-Lactamase) production analysis in E. coli strains from the Rio Grande/Rio Bravo River in Tamaulipas, Mexico
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Requena-Castro, Rocío, Aguilera-Arreola, María Guadalupe, Martínez-Vázquez, Ana Verónica, Cruz-Pulido, Wendy Lizeth, Rivera, Gildardo, and Bocanegra-García, Virgilio
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- 2024
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