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1. Configuration Interaction Guided Sampling with Interpretable Restricted Boltzmann Machine

Author

Hernandez-Martinez, Jorge I., Rodriguez-Hernandez, Gerardo, and Mendez-Vazquez, Andres

Subjects
Computer Science - Machine Learning, Physics - Computational Physics
Abstract

We propose a data-driven approach using a Restricted Boltzmann Machine (RBM) to solve the Schr\"odinger equation in configuration space. Traditional Configuration Interaction (CI) methods, while powerful, are computationally expensive due to the large number of determinants required. Our approach leverages RBMs to efficiently identify and sample the most significant determinants, accelerating convergence and reducing computational cost. This method achieves up to 99.99\% of the correlation energy even by four orders of magnitude less determinants compared to full CI calculations and up to two orders of magnitude less than previous state of the art works. Additionally, our study demonstrate that the RBM can learn the underlying quantum properties, providing more detail insights than other methods . This innovative data-driven approach offers a promising tool for quantum chemistry, enhancing both efficiency and understanding of complex systems., Comment: Preprint to be submitted to Computer Physics Communications

Published
2024

3. Pre-processing of the Text of ECU 911 Emergency Calls

Author

Orellana, Marcos, Molina Pinos, Pablo Andres, García-Montero, Patricio Santiago, Zambrano-Martinez, Jorge Luis, Ghosh, Ashish, Editorial Board Member, Berrezueta-Guzman, Santiago, editor, Torres, Rommel, editor, Zambrano-Martinez, Jorge Luis, editor, and Herrera-Tapia, Jorge, editor

Published
2025
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4. Automatic Parking Space Segmentation Using K-Means Clustering and Image Processing Techniques

Author

Romero Gonzalez, Anthony Xavier, Campoverde Ambrosi, Kevin Sebastian, Ramon Celi, Patricio Eduardo, Bermeo, Alexandra, Orellana, Marcos, Zambrano-Martinez, Jorge Luis, García-Montero, Patricio Santiago, Ghosh, Ashish, Editorial Board Member, Berrezueta-Guzman, Santiago, editor, Torres, Rommel, editor, Zambrano-Martinez, Jorge Luis, editor, and Herrera-Tapia, Jorge, editor

Published
2025
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5. Evoking stable and precise tactile sensations via multi-electrode intracortical microstimulation of the somatosensory cortex

Author

Greenspon, Charles M., Valle, Giacomo, Shelchkova, Natalya D., Hobbs, Taylor G., Verbaarschot, Ceci, Callier, Thierri, Berger-Wolf, Ev I., Okorokova, Elizaveta V., Hutchison, Brianna C., Dogruoz, Efe, Sobinov, Anton R., Jordan, Patrick M., Weiss, Jeffrey M., Fitzgerald, Emily E., Prasad, Dillan, Van Driesche, Ashley, He, Qinpu, Liu, Fang, Kirsch, Robert F., Miller, Jonathan P., Lee, Ray C., Satzer, David, Gonzalez-Martinez, Jorge, Warnke, Peter C., Ajiboye, Abidemi B., Graczyk, Emily L., Boninger, Michael L., Collinger, Jennifer L., Downey, John E., Miller, Lee E., Hatsopoulos, Nicholas G., Gaunt, Robert A., and Bensmaia, Sliman J.

Published
2024
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7. Dynamic modeling and predictive control of a microfluidic system

Author

Martinez, Jorge Vicente, Ramirez-Laboreo, Edgar, and Gil, Pablo Calderon

Subjects
Electrical Engineering and Systems Science - Systems and Control
Abstract

Microfluidics, the study of fluids in microscopic channels, has led to important advances in fields as diverse as microelectronics, biotechnology and chemistry. Microfluidic research is primarily based on the use of microfluidic chips, low-cost devices that can be used to perform laboratory experiments using small amounts of fluid. These systems, however, require advanced control mechanisms in order to accurately achieve the flow rates and pressures required in the experiments. In this paper, we present the design of a model predictive controller intended to regulate the fluid flows in one of these systems. The results obtained, both through simulations and real experiments performed on the device, show that predictive control is an ideal technique to control these systems, especially taking into account all the existing constraints., Comment: 12 pages, 17 figures. This is an author-approved English translation of a paper accepted for publication (see Related DOI)

Published
2024
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8. Potentiation of cortico-spinal output via targeted electrical stimulation of the motor thalamus

Author

Ho, Jonathan C., Grigsby, Erinn M., Damiani, Arianna, Liang, Lucy, Balaguer, Josep-Maria, Kallakuri, Sridula, Tang, Lilly W., Barrios-Martinez, Jessica, Karapetyan, Vahagn, Fields, Daryl, Gerszten, Peter C., Hitchens, T. Kevin, Constantine, Theodora, Adams, Gregory M., Crammond, Donald J., Capogrosso, Marco, Gonzalez-Martinez, Jorge A., and Pirondini, Elvira

Published
2024
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11. Robot path planning using deep reinforcement learning

Author

Quinones-Ramirez, Miguel, Rios-Martinez, Jorge, and Uc-Cetina, Victor

Subjects
Computer Science - Robotics, Computer Science - Artificial Intelligence
Abstract

Autonomous navigation is challenging for mobile robots, especially in an unknown environment. Commonly, the robot requires multiple sensors to map the environment, locate itself, and make a plan to reach the target. However, reinforcement learning methods offer an alternative to map-free navigation tasks by learning the optimal actions to take. In this article, deep reinforcement learning agents are implemented using variants of the deep Q networks method, the D3QN and rainbow algorithms, for both the obstacle avoidance and the goal-oriented navigation task. The agents are trained and evaluated in a simulated environment. Furthermore, an analysis of the changes in the behaviour and performance of the agents caused by modifications in the reward function is conducted.

Published
2023

12. Enhanced Recovery Protocol Decreases Postoperative Opioid Use after Penile Inversion Vaginoplasty

Author

Maria V. Rios Sanchez, MPH, Nicole Sanchez Figueroa, MD, Eugene Zheng, MD, Dan Sotelo Leon, MD, Jorys Martinez-Jorge, MD, and Vahe Fahradyan, MD

Subjects
Surgery, RD1-811
Abstract

Background:. Penile inversion vaginoplasty (PIV) entails considerable soft-tissue dissection to the perineal region and involves complex tissue rearrangement. This study examines the role of an enhanced recovery after surgery (ERAS) pathway after PIV in reducing opioid use and controlling postoperative pain. Methods:. A retrospective study of 50 transfemale patients who underwent PIV at a single institution from June 2021 to January 2023 was completed. The study compared 2 groups of patients who were given different postoperative pain management regimens: group A received standard postoperative analgesics and group B received ERAS. Variables such as postoperative pain scores on the numeric pain rating scale (0–10), use of opioid medication, length of hospital stay, and patient comorbidities were recorded and compared across the 2 groups. Results:. The average hospital stay length was 4.92 (±0.85) days. Group A had a slightly longer average stay compared with group B. The average pain level in both groups was 4.25 (SD ±1.51). Group A exhibited a slightly higher average pain level of 4.31 (±1.53), whereas group B exhibited 4.16 (SD±1.51) (P = 0.77). Although pain levels did not significantly vary between the 2 groups, there was a statistically significant decrease in the amount of opioid medication used in group B with a P value of 0.009. Conclusions:. ERAS protocol is effective in decreasing opioid usage in the immediate postoperative setting after PIV.

Published
2024
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14. Pathology of submeasures and $F_\sigma$ ideals

Author

Martínez, Jorge, Meza-Alcántara, David, and Uzcátegui, Carlos

Subjects
Mathematics - Functional Analysis, Mathematics - General Topology, Mathematics - Logic
Abstract

We address some phenomena about the interaction between lower semicontinuous submeasures on $\mathbb{N}$ and $F_{\sigma}$ ideals. We analyze the pathology degree of a submeasure and present a method to construct pathological $F_\sigma$ ideals. We give a partial answers to the question of whether every nonpathological tall $F_\sigma$ ideal is Kat\v{e}tov above the random ideal or at least has a Borel selector. Finally, we show a representation of nonpathological $F_\sigma$ ideals using sequences in Banach spaces., Comment: arXiv admin note: substantial text overlap with arXiv:2111.10598

Published
2022

16. Abstract 4143739: Enhancing Care for Patients with ACS in Mexico: Impact of the Get With The Guidelines®-Coronary Artery Disease Mexico Project at the National Institute of Cardiology

Author

Najera-Rojas, Andrea, Robles-Ledesma, Mariana, De Los Rios, Manuel, Lugo Gavidia, Leslie Marisol, Leiva, Jose Luis, De los ríos Arce, Luis Fernando, Gopar-Nieto, Rodrigo, Sierra Lara Martinez, Jorge Daniel, González Pacheco, Héctor, Arias-Mendoza, Alexandra, and Araiza, Diego

Published
2024
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18. Abstract 4136498: Analysis of Cardiovascular Events in Cancer Survivors: A Comparative Study of Solid Tumors and Hematologic Malignancies at a Tertiary Cardiovascular Center

Author

Amaro Palomo, Eder Jonathan, Latapi Ruiz Esparza, Ximena, Adib Gracia, Anna Elisa, Garate Togo, Javier, Sierra Lara Martinez, Jorge Daniel, Hernandez Pastrana, Sarai, Gonzalez Macedo, Eder, Santiago Hernández, Alberto, Neri Bale, Raul Rodrigo, Cortes Flores, Claudia Galilea, Diaz, Braiana, Araiza, Diego, Arias-Mendoza, Alexandra, and MARTINEZ RIOS, MARCO ANTONIO

Published
2024
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20. Text Mining Techniques and Pre-trained Models Applied to the Issues in Pictograms: A Systematic Literature Review

Author

Patiño-León, Andrés, Zambrano-Martinez, Jorge Luis, Orellana, Marcos, Serrano, María Verónica, Ramón, Daniel, Cedillo, Priscila, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Vizuete, Marcelo Zambrano, editor, Tobar, Miguel Botto, editor, Casillas, Sonia, editor, Toro, Miguel Naranjo, editor, Basantes Andrade, Andrea, editor, Carrasco, Francisco Pérez, editor, and Durakovic, Benjamin, editor

Published
2024
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23. SparksAIR: A Low-Cost IoT Solution to Manage Air Pollution in Urban Areas

Author

Zamora, Willian, Zambrano-Martinez, Jorge Luis, Calafate, Carlos T., Ponce-Jara, Marcos, Machuca, Mike, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Botto-Tobar, Miguel, editor, Zambrano Vizuete, Marcelo, editor, Montes León, Sergio, editor, Torres-Carrión, Pablo, editor, and Durakovic, Benjamin, editor

Published
2024
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24. Adaptive Sharing of IoT Resources Through SDN-Based Microsegmentation of Services Using Mininet

Author

Martínez, Angely, Padrón, José D., Zambrano-Martinez, Jorge Luis, Calafate, Carlos T., Akan, Ozgur, Editorial Board Member, Bellavista, Paolo, Editorial Board Member, Cao, Jiannong, Editorial Board Member, Coulson, Geoffrey, Editorial Board Member, Dressler, Falko, Editorial Board Member, Ferrari, Domenico, Editorial Board Member, Gerla, Mario, Editorial Board Member, Kobayashi, Hisashi, Editorial Board Member, Palazzo, Sergio, Editorial Board Member, Sahni, Sartaj, Editorial Board Member, Shen, Xuemin, Editorial Board Member, Stan, Mircea, Editorial Board Member, Jia, Xiaohua, Editorial Board Member, Zomaya, Albert Y., Editorial Board Member, Guisado-Lizar, José-Luis, editor, Riscos-Núñez, Agustín, editor, Morón-Fernández, María-José, editor, and Wainer, Gabriel, editor

Published
2024
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26. Automatic Assessment of Canine Trainability Using Heart Rate Responses to Positive and Negative Emotional Stimuli

Author

Ospina-De la Cruz, Cristian A., Pérez-Espinosa, Humberto, Urbina-Escalante, Mariel, Reyes-Meza, Verónica, Ríos-Martínez, Jorge, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Calvo, Hiram, editor, Martínez-Villaseñor, Lourdes, editor, and Ponce, Hiram, editor

Published
2024
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30. On the Integration of Acoustics and LiDAR: a Multi-Modal Approach to Acoustic Reflector Estimation

Author

Riemens, Ellen, Martínez-Nuevo, Pablo, Martinez, Jorge, Møller, Martin, and Hendriks, Richard C.

Subjects
Electrical Engineering and Systems Science - Audio and Speech Processing, Electrical Engineering and Systems Science - Signal Processing
Abstract

Having knowledge on the room acoustic properties, e.g., the location of acoustic reflectors, allows to better reproduce the sound field as intended. Current state-of-the-art methods for room boundary detection using microphone measurements typically focus on a two-dimensional setting, causing a model mismatch when employed in real-life scenarios. Detection of arbitrary reflectors in three dimensions encounters practical limitations, e.g., the need for a spherical array and the increased computational complexity. Moreover, loudspeakers may not have an omnidirectional directivity pattern, as usually assumed in the literature, making the detection of acoustic reflectors in some directions more challenging. In the proposed method, a LiDAR sensor is added to a loudspeaker to improve wall detection accuracy and robustness. This is done in two ways. First, the model mismatch introduced by horizontal reflectors can be resolved by detecting reflectors with the LiDAR sensor to enable elimination of their detrimental influence from the 2D problem in pre-processing. Second, a LiDAR-based method is proposed to compensate for the challenging directions where the directive loudspeaker emits little energy. We show via simulations that this multi-modal approach, i.e., combining microphone and LiDAR sensors, improves the robustness and accuracy of wall detection., Comment: 5 pages, 9 figures, to be published in EUSIPCO 2022

Published
2022

31. Highlights From the Annual Meeting of the American Epilepsy Society 2022

Author

Valencia, Ignacio, Alexander, Allyson L, Andrade, Danielle M, Arevalo-Astrada, Miguel, Rubiños, Clio, Auer, Nancy, Bainbridge, Jacquelyn L, Baxendale, Sallie A, Bartolomei, Fabrice, Becker, Danielle A, Berg, Anne T, Bernasconi, Andrea, Bernasconi, Neda, Bernhardt, Boris, Bhatnagar, Shivani, Blümcke, Ingmar, Blumenfeld, Hal, Buchanan, Gordon F, Burdette, David E, Burneo, Jorge G, Busch, Robyn M, Chauvel, Patrick, Chin, Jeannie, Clifford, Lisa, Conner, Kelly R, Cook, Mark J, Conway, Jeannine, Diaz-Arastia, Ramon, Drees, Cornelia, French, Jacqueline A, Ganguly, Taneeta Mindy, Gelfand, Michael A, Glauser, Tracy A, Gleichgerrcht, Ezequiel, Goldman, Alica M, Gonzalez-Martinez, Jorge, Gotman, Jean, Grinspan, Zachary, Guilfoyle, Shanna, Gupta, Gita, Hammer, Michael, Hartman, Adam L, Hentges, Katie, Hogan, R Edward, Huh, Linda, Hyslop, Ann, Jobst, Barbara, Josephson, Colin B, Kelley, Sarah A, Knupp, Kelly, Koepp, Matthias, Kothare, Sanjeev V, Krook-Magnuson, Esther, Kwasa, Jasmine, La Vega-Talbott, Maite, Lam, Alice D, Lee, Jong Woo, Lowenstein, Daniel H, Maturu, Sarita, Mayor, Luis Carlos, McDonald, Carrie, McKee, Heather R, McKhann, Guy M, Meador, Kimford J, Mefford, Heather C, Michael, Elizabeth H, Mikati, Mohamad A, Millichap, John J, Mitchell, James W, Myers, Leah S, Naritoku, Dean, Neville, Kerri L, Noebels, Jeffrey, O’Brien, Terence J, Oluigbo, Chima O, Patel, Anup D, Pavlova, Milena K, T. Paz, Jeanne, Pennell, Page B, Perry, M Scott, Perucca, Piero, Pitkänen, Asla, Plueger, Madona, Pugh, Mary Jo, Quigg, Mark, Reddy, Shilpa B, Ryan, Christopher, Reynolds, Tamara S, Sajatovic, Martha, Santana-Gomez, Cesar, Schommer, Linsday, Schuele, Stephan, Shellhaas, Renée A, Shrey, Daniel W, Singh, Rani K, Sperling, Michael R, Suleman, Saher, Templer, Jessica W, Thom, Maria, and Trinka, Eugen

Subjects
Biomedical and Clinical Sciences, Neurosciences, Epilepsy, Neurodegenerative, Brain Disorders, Neurological, Good Health and Well Being, epilepsy, annual meeting, American Epilepsy Society, Biological psychology
Abstract

With more than 6000 attendees between in-person and virtual offerings, the American Epilepsy Society Meeting 2022 in Nashville, felt as busy as in prepandemic times. An ever-growing number of physicians, scientists, and allied health professionals gathered to learn a variety of topics about epilepsy. The program was carefully tailored to meet the needs of professionals with different interests and career stages. This article summarizes the different symposia presented at the meeting. Basic science lectures addressed the primary elements of seizure generation and pathophysiology of epilepsy in different disease states. Scientists congregated to learn about anti-seizure medications, mechanisms of action, and new tools to treat epilepsy including surgery and neurostimulation. Some symposia were also dedicated to discuss epilepsy comorbidities and practical issues regarding epilepsy care. An increasing number of patient advocates discussing their stories were intertwined within scientific activities. Many smaller group sessions targeted more specific topics to encourage member participation, including Special Interest Groups, Investigator, and Skills Workshops. Special lectures included the renown Hoyer and Lombroso, an ILAE/IBE joint session, a spotlight on the impact of Dobbs v. Jackson on reproductive health in epilepsy, and a joint session with the NAEC on coding and reimbursement policies. The hot topics symposium was focused on traumatic brain injury and post-traumatic epilepsy. A balanced collaboration with the industry allowed presentations of the latest pharmaceutical and engineering advances in satellite symposia.

Published
2023

34. Changes in entire acute bronchiolitis seasons before, during, and after the COVID-19 pandemic in Spain

Author

Rius-Peris, J.M., Maraña Pérez, A.I., Valiente Armero, A., Guardia Nieto, L., Torrecilla Cañas, J., Cueto Calvo, E.M., Marcilla Vázquez, C., Pareja León, M., Roda Martínez, N., Molini Menchón, N., Felipe Almira, E., Párraga Cifuentes, A., Sequí-Canet, J.M., Olmos García, J.M., Martínez Bayo, A., Escrivá Tomás, P., Povo Martín, S., Pantoja-Martínez, J., Caballero Mora, F.J., García Maset, L., Coret Sinisterra, A., Castillo Ochando, F., Garrido Sánchez, M.J., Edo Tena, A., Vázquez Álvarez, L., Rabasco Álvarez, L., Moya Díaz-Pintado, M.T., Cardete Pascual, I., García Candel, S., Amat Madramany, A., Moreno López, M., Pons Morales, S., Vicent Castelló, M.C., Rivera Figueiras, A.M., Herrero Galiana, A., González de Dios, J., Domingo Pla, A., Gil Piquer, R., Rius-Peris, Juan Manuel, Vicent Castelló, María del Carmen, Pareja León, Marta, Pons Morales, Sara, Amat Madramany, Ana, Pantoja-Martínez, Jorge, Gil Piquer, Raquel, Roda Martínez, Nuria, Coret Sinisterra, Alicia, Castillo Ochando, Francisca, Caballero Mora, Francisco Javier, and Moya Díaz-Pintado, María Teresa

Published
2024
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38. A randomized trial of antithrombotic therapy in patients with acute coronary syndrome and coronary ectasia

Author

Araiza-Garaygordobil, Diego, Gopar-Nieto, Rodrigo, Sierra-Lara Martínez, Jorge Daniel, Mullasari, Ajit S, Belderrain-Morales, Nallely, Nájera-Rojas, Nitzha Andrea, Diaz-Herrera, Braiana Angeles, Sarabia-Chao, Vianney, Alfaro-Ponce, Diana Laura, Briseño-De la Cruz, Jose Luis, Ruiz-Beltrán, Maximiliano, Martínez-Ríos, Marco Antonio, Piña-Reyna, Yigal, Latapi-Ruiz Esparza, Ximena, Grimaldo-Gomez, Flavio Adrian, Cortina-De la Rosa, Evelyn, Romero-Arroyo, María Oliva, Sierra-Gonzalez de Cossio, Alejandro, González-Pacheco, Héctor, and Arias-Mendoza, Alexandra

Published
2025
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40. Jalisco's multiclass land cover analysis and classification using a novel lightweight convnet with real-world multispectral and relief data

Author

Quevedo, Alexander, Sánchez, Abraham, Nancláres, Raul, Montoya, Diana P., Pacho, Juan, Martínez, Jorge, and Moya-Sánchez, E. Ulises

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Artificial Intelligence
Abstract

The understanding of global climate change, agriculture resilience, and deforestation control rely on the timely observations of the Land Use and Land Cover Change (LULCC). Recently, some deep learning (DL) methods have been adapted to make an automatic classification of Land Cover (LC) for global and homogeneous data. However, most of these DL models can not apply effectively to real-world data. i.e. a large number of classes, multi-seasonal data, diverse climate regions, high imbalance label dataset, and low-spatial resolution. In this work, we present our novel lightweight (only 89k parameters) Convolution Neural Network (ConvNet) to make LC classification and analysis to handle these problems for the Jalisco region. In contrast to the global approaches, the regional data provide the context-specificity that is required for policymakers to plan the land use and management, conservation areas, or ecosystem services. In this work, we combine three real-world open data sources to obtain 13 channels. Our embedded analysis anticipates the limited performance in some classes and gives us the opportunity to group the most similar, as a result, the test accuracy performance increase from 73 % to 83 %. We hope that this research helps other regional groups with limited data sources or computational resources to attain the United Nations Sustainable Development Goal (SDG) concerning Life on Land., Comment: 12 pages

Published
2022

48. Widespread ripples synchronize human cortical activity during sleep, waking, and memory recall

Author

Dickey, Charles W, Verzhbinsky, Ilya A, Jiang, Xi, Rosen, Burke Q, Kajfez, Sophie, Stedelin, Brittany, Shih, Jerry J, Ben-Haim, Sharona, Raslan, Ahmed M, Eskandar, Emad N, Gonzalez-Martinez, Jorge, Cash, Sydney S, and Halgren, Eric

Subjects
Clinical Research, Behavioral and Social Science, Basic Behavioral and Social Science, Sleep Research, Mental Health, Neurosciences, Underpinning research, 1.1 Normal biological development and functioning, Neurological, Cerebral Cortex, Electrocorticography, Hippocampus, Humans, Memory Consolidation, Mental Recall, Sleep, Wakefulness, ripples, cortex, hippocampus, non-rapid eye movement sleep, waking
Abstract

Declarative memory encoding, consolidation, and retrieval require the integration of elements encoded in widespread cortical locations. The mechanism whereby such "binding" of different components of mental events into unified representations occurs is unknown. The "binding-by-synchrony" theory proposes that distributed encoding areas are bound by synchronous oscillations enabling enhanced communication. However, evidence for such oscillations is sparse. Brief high-frequency oscillations ("ripples") occur in the hippocampus and cortex and help organize memory recall and consolidation. Here, using intracranial recordings in humans, we report that these ∼70-ms-duration, 90-Hz ripples often couple (within ±500 ms), co-occur (≥ 25-ms overlap), and, crucially, phase-lock (have consistent phase lags) between widely distributed focal cortical locations during both sleep and waking, even between hemispheres. Cortical ripple co-occurrence is facilitated through activation across multiple sites, and phase locking increases with more cortical sites corippling. Ripples in all cortical areas co-occur with hippocampal ripples but do not phase-lock with them, further suggesting that cortico-cortical synchrony is mediated by cortico-cortical connections. Ripple phase lags vary across sleep nights, consistent with participation in different networks. During waking, we show that hippocampo-cortical and cortico-cortical coripples increase preceding successful delayed memory recall, when binding between the cue and response is essential. Ripples increase and phase-modulate unit firing, and coripples increase high-frequency correlations between areas, suggesting synchronized unit spiking facilitating information exchange. co-occurrence, phase synchrony, and high-frequency correlation are maintained with little decrement over very long distances (25 cm). Hippocampo-cortico-cortical coripples appear to possess the essential properties necessary to support binding by synchrony during memory retrieval and perhaps generally in cognition.

Published
2022

49. Human Spindle Variability.

Author

Gonzalez, Christopher, Jiang, Xi, Gonzalez-Martinez, Jorge, and Halgren, Eric

Subjects
Neurosciences, Basic Behavioral and Social Science, Behavioral and Social Science, Clinical Research, 1.1 Normal biological development and functioning, Underpinning research, Mental health, Electroencephalography, Female, Hippocampus, Humans, Male, Memory Consolidation, Sleep, Sleep Stages, cortex, hippocampus, intracranial, sleep, slow oscillation, spindle, Medical and Health Sciences, Psychology and Cognitive Sciences, Neurology & Neurosurgery
Abstract

In humans, sleep spindles are 10- to 16-Hz oscillations lasting approximately 0.5-2 s. Spindles, along with cortical slow oscillations, may facilitate memory consolidation by enabling synaptic plasticity. Early recordings of spindles at the scalp found anterior channels had overall slower frequency than central-posterior channels. This robust, topographical finding led to dichotomizing spindles as "slow" versus "fast," modeled as two distinct spindle generators in frontal versus posterior cortex. Using a large dataset of intracranial stereoelectroencephalographic (sEEG) recordings from 20 patients (13 female, 7 male) and 365 bipolar recordings, we show that the difference in spindle frequency between frontal and parietal channels is comparable to the variability in spindle frequency within the course of individual spindles, across different spindles recorded by a given site, and across sites within a given region. Thus, fast and slow spindles only capture average differences that obscure a much larger underlying overlap in frequency. Furthermore, differences in mean frequency are only one of several ways that spindles differ. For example, compared with parietal, frontal spindles are smaller, tend to occur after parietal when both are engaged, and show a larger decrease in frequency within-spindles. However, frontal and parietal spindles are similar in being longer, less variable, and more widespread than occipital, temporal, and Rolandic spindles. These characteristics are accentuated in spindles which are highly phase-locked to posterior hippocampal spindles. We propose that rather than a strict parietal-fast/frontal-slow dichotomy, spindles differ continuously and quasi-independently in multiple dimensions, with variability due about equally to within-spindle, within-region, and between-region factors.SIGNIFICANCE STATEMENT Sleep spindles are 10- to 16-Hz neural oscillations generated by cortico-thalamic circuits that promote memory consolidation. Spindles are often dichotomized into slow-anterior and fast-posterior categories for cognitive and clinical studies. Here, we show that the anterior-posterior difference in spindle frequency is comparable to that observed between different cycles of individual spindles, between spindles from a given site, or from different sites within a region. Further, we show that spindles vary on other dimensions such as duration, amplitude, spread, primacy and consistency, and that these multiple dimensions vary continuously and largely independently across cortical regions. These findings suggest that multiple continuous variables rather than a strict frequency dichotomy may be more useful biomarkers for memory consolidation or psychiatric disorders.

Published
2022

50. Finding an Integrated Ultraviolet Radiation Index Using Fuzzy Logic Techniques

Author

Huricocha Piedra, Juan Pablo, Orellana, Marcos, Cedillo, Priscila, Zambrano-Martinez, Jorge Luis, Lima, Juan-Fernando, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Maldonado-Mahauad, Jorge, editor, Herrera-Tapia, Jorge, editor, Zambrano-Martínez, Jorge Luis, editor, and Berrezueta, Santiago, editor

Published
2023
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