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103. Toward next-generation primate neuroscience: A collaboration-based strategic plan for integrative neuroimaging

Author

Milham, Michael, primary, Petkov, Chris, additional, Belin, Pascal, additional, Ben Hamed, Suliann, additional, Evrard, Henry, additional, Fair, Damien, additional, Fox, Andrew, additional, Froudist-Walsh, Sean, additional, Hayashi, Takuya, additional, Kastner, Sabine, additional, Klink, Chris, additional, Majka, Piotr, additional, Mars, Rogier, additional, Messinger, Adam, additional, Poirier, Colline, additional, Schroeder, Charles, additional, Shmuel, Amir, additional, Silva, Afonso C., additional, Vanduffel, Wim, additional, Van Essen, David C., additional, Wang, Zheng, additional, Roe, Anna Wang, additional, Wilke, Melanie, additional, Xu, Ting, additional, Aarabi, Mohammad Hadi, additional, Adolphs, Ralph, additional, Ahuja, Aarit, additional, Alvand, Ashkan, additional, Amiez, Celine, additional, Autio, Joonas, additional, Azadi, Reza, additional, Baeg, Eunha, additional, Bai, Ruiliang, additional, Bao, Pinglei, additional, Basso, Michele, additional, Behel, Austin K., additional, Bennett, Yvonne, additional, Bernhardt, Boris, additional, Biswal, Bharat, additional, Boopathy, Sethu, additional, Boretius, Susann, additional, Borra, Elena, additional, Boshra, Rober, additional, Buffalo, Elizabeth, additional, Cao, Long, additional, Cavanaugh, James, additional, Celine, Amiez, additional, Chavez, Gianfranco, additional, Chen, Li Min, additional, Chen, Xiaodong, additional, Cheng, Luqi, additional, Chouinard-Decorte, Francois, additional, Clavagnier, Simon, additional, Cléry, Justine, additional, Colcombe, Stan J., additional, Conway, Bevil, additional, Cordeau, Melina, additional, Coulon, Olivier, additional, Cui, Yue, additional, Dadarwal, Rakshit, additional, Dahnke, Robert, additional, Desrochers, Theresa, additional, Deying, Li, additional, Dougherty, Kacie, additional, Doyle, Hannah, additional, Drzewiecki, Carly M., additional, Duyck, Marianne, additional, Arachchi, Wasana Ediri, additional, Elorette, Catherine, additional, Essamlali, Abdelhadi, additional, Evans, Alan, additional, Fajardo, Alfonso, additional, Figueroa, Hector, additional, Franco, Alexandre, additional, Freches, Guilherme, additional, Frey, Steve, additional, Friedrich, Patrick, additional, Fujimoto, Atsushi, additional, Fukunaga, Masaki, additional, Gacoin, Maeva, additional, Gallardo, Guillermo, additional, Gao, Lixia, additional, Gao, Yang, additional, Garside, Danny, additional, Garza-Villarreal, Eduardo A., additional, Gaudet-Trafit, Maxime, additional, Gerbella, Marzio, additional, Giavasis, Steven, additional, Glen, Daniel, additional, Ribeiro Gomes, Ana Rita, additional, Torrecilla, Sandra Gonzalez, additional, Gozzi, Alessandro, additional, Gulli, Roberto, additional, Haber, Suzanne, additional, Hadj-Bouziane, Fadila, additional, Fujimoto, Satoka Hashimoto, additional, Hawrylycz, Michael, additional, He, Quansheng, additional, He, Ye, additional, Heuer, Katja, additional, Hiba, Bassem, additional, Hoffstaedter, Felix, additional, Hong, Seok-Jun, additional, Hori, Yuki, additional, Hou, Yujie, additional, Howard, Amy, additional, de la Iglesia-Vaya, Maria, additional, Ikeda, Takuro, additional, Jankovic-Rapan, Lucija, additional, Jaramillo, Jorge, additional, Jedema, Hank P., additional, Jin, Hecheng, additional, Jiang, Minqing, additional, Jung, Benjamin, additional, Kagan, Igor, additional, Kahn, Itamar, additional, Kiar, Gregory, additional, Kikuchi, Yuki, additional, Kilavik, Bjørg, additional, Kimura, Nobuyuki, additional, Klatzmann, Ulysse, additional, Kwok, Sze Chai, additional, Lai, Hsin-Yi, additional, Lamberton, Franck, additional, Lehman, Julia, additional, Li, Pengcheng, additional, Li, Xinhui, additional, Li, Xinjian, additional, Liang, Zhifeng, additional, Liston, Conor, additional, Little, Roger, additional, Liu, Cirong, additional, Liu, Ning, additional, Liu, Xiaojin, additional, Liu, Xinyu, additional, Lu, Haidong, additional, Loh, Kep Kee, additional, Madan, Christopher, additional, Magrou, Loïc, additional, Margulies, Daniel, additional, Mathilda, Froesel, additional, Mejia, Sheyla, additional, Meng, Yao, additional, Menon, Ravi, additional, Meunier, David, additional, Mitchell, A.J., additional, Mitchell, Anna, additional, Murphy, Aidan, additional, Mvula, Towela, additional, Ortiz-Rios, Michael, additional, Ortuzar Martinez, Diego Emanuel, additional, Pagani, Marco, additional, Palomero-Gallagher, Nicola, additional, Pareek, Vikas, additional, Perkins, Pierce, additional, Ponce, Fernanda, additional, Postans, Mark, additional, Pouget, Pierre, additional, Qian, Meizhen, additional, Ramirez, Julian “Bene”, additional, Raven, Erika, additional, Restrepo, Isabel, additional, Rima, Samy, additional, Rockland, Kathleen, additional, Rodriguez, Nadira Yusif, additional, Roger, Elise, additional, Hortelano, Eduardo Rojas, additional, Rosa, Marcello, additional, Rossi, Andrew, additional, Rudebeck, Peter, additional, Russ, Brian, additional, Sakai, Tomoko, additional, Saleem, Kadharbatcha S., additional, Sallet, Jerome, additional, Sawiak, Stephen, additional, Schaeffer, David, additional, Schwiedrzik, Caspar M., additional, Seidlitz, Jakob, additional, Sein, Julien, additional, Sharma, Jitendra, additional, Shen, Kelly, additional, Sheng, Wei-an, additional, Shi, Neo Sunhang, additional, Shim, Won Mok, additional, Simone, Luciano, additional, Sirmpilatze, Nikoloz, additional, Sivan, Virginie, additional, Song, Xiaowei, additional, Tanenbaum, Aaron, additional, Tasserie, Jordy, additional, Taylor, Paul, additional, Tian, Xiaoguang, additional, Toro, Roberto, additional, Trambaiolli, Lucas, additional, Upright, Nick, additional, Vezoli, Julien, additional, Vickery, Sam, additional, Villalon, Julio, additional, Wang, Xiaojie, additional, Wang, Yufan, additional, Weiss, Alison R., additional, Wilson, Charlie, additional, Wong, Ting-Yat, additional, Woo, Choong-Wan, additional, Wu, Bichan, additional, Xiao, Du, additional, Xu, Augix Guohua, additional, Xu, Dongrong, additional, Xufeng, Zhou, additional, Yacoub, Essa, additional, Ye, Ningrong, additional, Ying, Zhang, additional, Yokoyama, Chihiro, additional, Yu, Xiongjie, additional, Yue, Shasha, additional, Yuheng, Lu, additional, Yumeng, Xin, additional, Zaldivar, Daniel, additional, Zhang, Shaomin, additional, Zhao, Yuguang, additional, and Zuo, Zhanguang, additional

Published
2022
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119. Dopamine is signaled by mid-frequency oscillations and boosts output-layers visual information in visual cortex

Author

Zaldivar, Daniel, Goense, Jozien, Lowe, Scott C., Logothetis, Nikos K., and Panzeri, Stefano

Abstract

Neural oscillations are ubiquitously observed in cortical activity, and are widely believed to be crucial for mediating transmission of information across the cortex. Yet, the neural phenomena contributing to each oscillation band, and their effect on information coding and transmission, are largely unknown. Here, we investigated whether individual frequency bands specifically reflect changes in the concentrations of dopamine, an important neuromodulator, and how dopamine affects oscillatory information processing. We recorded the local field potential (LFP) at different depths of primary visual cortex (V1) in anesthetized monkeys (Macaca mulatta) during spontaneous activity and during visual stimulation with Hollywood movie clips while pharmacologically mimicking dopaminergic neuromodulation by systemic injection of L-DOPA (a metabolic precursor of dopamine). We found that dopaminergic neuromodulation had marked effects on both spontaneous and movie-evoked neural activity. During spontaneous activity, dopaminergic neuromodulation increased the power of the LFP specifically in the [19–38 Hz] band, suggesting that the power of endogenous visual cortex oscillations in this band can be used as a robust marker of dopaminergic neuromodulation. Moreover, dopamine increased visual information encoding over all frequencies during movie stimulation. The information increase due to dopamine was prominent in the supragranular layers of cortex that project to higher cortical areas and in the gamma [50–100 Hz] band that has been previously implicated in mediating feedforward information transfer. These results thus individuate new neural mechanisms by which dopamine may promote the readout of relevant sensory information by strengthening the transmission of information from primary to higher areas.

Published
2018

120. Improved Unsupervised Color Segmentation Using a Modified HSV Color Model and a Bagging Procedure in K-Means++ Algorithm

Author

Chavolla, Edgar, Valdivia, Arturo, Diaz, Primitivo, Zaldivar, Daniel, Cuevas, Erik, and Perez, Marco A.

Subjects
Article Subject, lcsh:TA1-2040, lcsh:Mathematics, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, lcsh:Engineering (General). Civil engineering (General), lcsh:QA1-939
Abstract

Accurate color image segmentation has stayed as a relevant topic between the researches/scientific community due to the wide range of application areas such as medicine and agriculture. A major issue is the presence of illumination variations that obstruct precise segmentation. On the other hand, the machine learning unsupervised techniques have become attractive principally for the easy implementations. However, there is not an easy way to verify or ensure the accuracy of the unsupervised techniques; so these techniques could lead to an unknown result. This paper proposes an algorithm and a modification to the HSV color model in order to improve the accuracy of the results obtained from the color segmentation using the K-means++ algorithm. The proposal gives better segmentation and less erroneous color detections due to illumination conditions. This is achieved shifting the hue and rearranging the H equation in order to avoid undefined conditions and increase robustness in the color model.

Published
2018

124. Learning classical and metaheuristic optimization techniques by using an educational platform based on LEGO robots.

Author

Zaldivar, Daniel, Cuevas, Erik, Maciel, Oscar, Valdivia, Arturo, Chavolla, Edgar, and Oliva, Diego

Subjects
*METAHEURISTIC algorithms, *MATHEMATICAL optimization, *ENGINEERING students, *ROBOTS, *LEARNING
Abstract

Optimization is a very important issue to efficiently solve engineering problems. The clear comprehension of the elements and processes of optimizer algorithms is fundamental to ensure that engineer students are capable to apply, tune, and design new algorithms. This paper presents an educational platform based on LEGO© EV3 and MATLAB to assist the learning of the principles of classical and metaheuristic optimization algorithms at undergraduate level, by providing a simple and easy-to-follow teaching setup. The proposed study aims to accompany students through the learning of optimization fundamentals by building hands-on robotic experiments. The proposed educational platform has been successfully applied to several undergraduate courses within the Electronics Department at the University of Guadalajara. The description of each experiment and the evaluation of their impact in the student performance are both provided in the paper. [ABSTRACT FROM AUTHOR]

Published
2021
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130. In vivo characterization of the downfield part of 1H MR spectra of human brain at 9.4 T: Magnetization exchange with water and relation to conventionally determined metabolite content.

Author

Fichtner, Nicole D., Giapitzakis, Ioannis‐Angelos, Avdievich, Nikolai, Mekle, Ralf, Zaldivar, Daniel, Henning, Anke, and Kreis, Roland

Abstract

Purpose: To perform exchange‐rate measurements on the in vivo human brain downfield spectrum (5–10 ppm) at 9.4 T and to compare the variation in concentrations of the downfield resonances and of known upfield metabolites to determine potential peak labels. Methods: Non‐water‐suppressed metabolite cycling was used in combination with an inversion transfer technique in two brain locations in healthy volunteers to measure the exchange rates and T1 values of exchanging peaks. Spectra were fitted with a heuristic model of a series of 13 or 14 Voigt lines, and a Bloch–McConnell model was used to fit the exchange rate curves. Concentrations from non‐water‐inverted spectra upfield and downfield were compared. Results: Mean T1 values ranged from 0.40 to 0.77 s, and exchange rates from 0.74 to 13.8 s−1. There were no significant correlations between downfield and upfield concentrations, except for N‐acetylaspartate, with a correlation coefficient of 0.63 and P < 0.01. Conclusions: Using ultrahigh field allowed improved separation of peaks in the 8.2 to 8.5 ppm amide proton region, and the exchange rates of multiple downfield resonances including the 5.8‐ppm peak, previously tentatively assigned to urea, were measured in vivo in human brain. Downfield peaks consisted of overlapping components, and largely missing correlations between upfield and downfield resonances—although not conclusive—indicate limited contributions from metabolites present upfield to the downfield spectrum. Magn Reson Med 79:2863–2873, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Published
2018
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137. Computer vision using MatLAB and the toolbox of image processing

Author

Cuevas, Erik, Zaldivar, Daniel, and Rojas, Raul

Subjects
000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

During the implementation of computer vision algorithms the manipulation of pointers, memory administration and some other resources are expensive in time even for friendly programming language. All these problems can be resolved if the implementation test is carried out in MatLAB using its toolbox of image processing with it the time of implementation becomes the minimum with the trust of using algorithms scientifically proven and robust. In this work we show the form in which can be used matlab and its toolboxes to solve common problems of computer vision efficiently.

Published
2005

138. Kalman filter for vision tracking

Author

Cuevas, Erik V., Zaldivar, Daniel, and Rojas, Raúl

Subjects
ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, ComputerApplications_COMPUTERSINOTHERSYSTEMS, 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

The Kalman filter has been used successfully in different prediction applications or state determination of a system. One important field in computer vision is the object tracking. Different movement conditions and occlusions can hinder the vision tracking of an object. In this report we present the use of the Kalman filter in the vision tracking. We consider the capacity of the Kalman filter to allow small occlusions and also the use of the extended Kalman filter (EKF) to model complex movements of objects.

Published
2005

139. Particle filter in vision tracking

Author

Cuevas, Erik V., Zaldivar, Daniel, and Rojas, Raúl

Subjects
lcsh:Social Sciences, lcsh:H, Computer Science::Robotics, Computer Science::Systems and Control, lcsh:Q, 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik, lcsh:Science
Abstract

El filtro de Kalman ha sido usado exitosamente en diferentes aplicaciones de predicción o determinación del estado de un sistema. Un campo importante en la visión por computadora es el seguimiento de objetos. Diferentes tipos de movimiento así como el ocultamiento de objetos a seguir pueden obstaculizar la labor de seguimiento. En este trabajo, se presenta el uso del filtro de Kalman para el seguimiento de objetos. Además se considera tanto la capacidad del filtro para tolerar pequeños ocultamientos del objeto así como el uso del filtro de Kalman extendido para el modelaje de movimientos complejos.

Published
2005

140. Bipedal robot description

Author

Cuevas, Eric, Zaldivar, Daniel, and Rojas, Raùl

Subjects
000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

This work report the electronic and mechanical for a bipedal robot prototype. The objective of this project is build a platform to study the dynamic walking and to prove some intelligent control techniques. This work highlighted the fact that mechanical design is equally, if not more important, than the control method used. All the elec- tronic was implemented in a low cost PIC16F873 microcontroller. The robot designed has 9 degree of freedom (DOF) and each joint is driven by a DC servo motor. A gait program besides a control algorithm who read a gyroscope and force sensors are used to equilibrate the robot at walking.

Published
2004
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141. Fuzzy segmentation applied to face segmentation

Author

Cuevas, Eric, Zaldivar, Daniel, and Rojas, Raùl

Subjects
000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

The segmentation of objects whose color-composition is not trivial represents a difficult task, due to the illumination and the appropriate threshold selection for each one of the object color-components. In this work we propose the Fuzzy C-Means algorithm application for the segmentation of such objects. It is chosen, by the characteristics that it represents the face segmentation. This technical report is organized in the following way: in section 1 a clustering techniques introduction are presented. In section 2 Fuzzy C-means algorithm is analysed and also showed with a simple example. In section 3 Matlab tools, that are used to code the fuzzy C-means algorithm are described. In section 4 the Fuzzy C-Means algorithm is implemented for the face segmentation. Finally in section 5 the results are presented and the possible improvements are proposed.

Published
2004
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144. Intelligent tracking

Author

Cuevas, Erik V., Zaldivar, Daniel, and Rojas, Raúl

Subjects
000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

In the robotics area, visual tracking is an important and difficult problem therefore is necessary to have a robust and efficient control algorithm which presents immunity characteristics to stochastic direction and speed changes of the object to be tracked. Also is important count with a segmentation algorithm which be able to tolerate changes in the intensity of light. We describe in this report the implementation of fuzzy controllers based on the fuzzy condensed algorithm and also the developed of a LVQ neural network to segment the image. For this work we used two fuzzy condensed algorithms running in a PC to control a robot’s head which tracks a human face. We describe the main lines of the fuzzy condensed algorithm as well as the LVQ neural networks architecture employed and the implementation, the fuzzy condensed controller performance in comparison to a PID controller and real time results.

Published
2003
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145. Competitive neural networks applied to face localization

Author

Cuevas, Erik V, Zaldivar, Daniel, and Rojas, Raúl

Subjects
ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, 000 Informatik, Informationswissenschaft, allgemeine Werke::000 Informatik, Wissen, Systeme::004 Datenverarbeitung, Informatik
Abstract

Color-segmentation is very sensitive to changes in the intensity of light. Many algorithms do not tolerate variations in color hue which correspond, in fact, to the same object. Learning Vector Quantization (LVQ) networks learn to recognize groups of similar input vectors in such a way that neurons physically near to each other in the neuron layer respond to similar input vectors. Learning is supervised, the inputs vectors into target classes are chosen by the user. In this work a new algorithm based on LVQ is presented. It involves neural networks that operate directly on the image pixels with a decision function. This algorithm has been applied to spotting and tracking human faces, and shows more robustness than other algorithms for the same task.

Published
2003
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146. Effects of lactate on the early visual cortex of non-human primates, investigated by pharmaco-MRI and neurochemical analysis

Author

Pföstl, Veronika von, Li, Juan, Zaldivar, Daniel, Goense, Jozien, Zhang, Xiaozhe, Serr, Nadine, Logothetis, Nikos K., Rauch, Alexander, Pföstl, Veronika von, Li, Juan, Zaldivar, Daniel, Goense, Jozien, Zhang, Xiaozhe, Serr, Nadine, Logothetis, Nikos K., and Rauch, Alexander

Abstract

In contrast to the limited use of functional magnetic resonance imaging (fMRI) in clinical diagnostics, it is currently a mainstay of neuroimaging in clinical and basic brain research. However, its non-invasive use in combination with its high temporal and spatial resolution would make fMRI a perfect diagnostic tool. We are interested in whether a pharmacological challenge imposed on the brain can be reliably traced by the blood oxygen level-dependent (BOLD) signal and possibly further exploited for diagnostics. We have chosen a systemic challenge with lactate and pyruvate to test whether the physiological formation of these monocarboxylic acids contributes to the BOLD signal and can be detected using fMRI. This information is also of interest because lactate levels in the cerebrospinal fluid rise concomitantly with reduced vascular responsiveness of the brain during the progression of Alzheimer disease (AD). We studied the BOLD response after a low-dose lactate challenge and monitored the induced plasma lactate levels in anesthetized non-human primates. We observed reliable lactate-induced BOLD responses, which could be confirmed at population and individual level by their strong correlation with systemic lactate concentrations. Comparable BOLD effects where observed after a slow infusion of pyruvate. We show here that physiological changes in lactate and pyruvate levels are indeed reflected in the BOLD signal, and describe the technical prerequisites to reliably trace a lactate challenge using BOLD-fMRI.

Published
2012

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