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Search Results: 1 - 10 of 19383 matches for " Miguel Angel Guevara "
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EEGcorco: a computer program to simultaneously calculate and statistically analyze EEG coherence and correlation  [PDF]
Miguel Angel Guevara, Marisela Hernández-González, Araceli Sanz-Martin, Claudia Amezcua
Journal of Biomedical Science and Engineering (JBiSE) , 2011, DOI: 10.4236/jbise.2011.412096
Abstract: EEGcorco is a computer program designed to analyze the degree of synchronization between two electroencephalographic signals (EEG) by mean the analysis of correlation and coherence index. The correlation and coherence values permit the quantitative determination of the similarity among EEG signals from homologous areas of the cerebral hemispheres (interhemispheric), and among localized areas within one cerebral hemisphere (intrahemispheric). EEG coherence is a function of frequency; thus it is commonly presented in a spectral manner (coherence values in every frequency of the spectrum), in contrast, the correlation function has been employed mainly to search periodic components of bioelectrical signals, and normally appears as punctual values defined in time, hence it is not common calculate correlation spectra. EEGcorco offers an easy and novel way to calculate correlation spectra by mean the application of the Fast Fourier Transformation (FFT) to digitized EEG signals. Both, correlation and coherence spectra are obtained in both independent frequencies and frequencies grouped in wide bands. Moreover, the program applies parametric statistical analyses to those coherence and correlation spectra also, for each individual frequency and for the frequencies grouped in bands. The program functions on any PC-compatible computer equipped with a Pentium or superior processor and a minimum of 512 Mb of RAM memory (though the higher the capacity the better). The space required on the hard disk depends on the signals to be analyzed, as the output takes the form of files in text format that occupy very little space. The program has been elaborated completely in the Delphi environment for the Windows operating system. The efficacy and versatility of EEGcorco allow it to be easily adapted to different experimental and clinical needs.
EEGbands: A Computer Program to Statistically Analyze Parameters of Electroencephalographic Signals  [PDF]
Miguel Angel Guevara, Araceli Sanz-Martin, Marisela Hernández-González
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.47032
Abstract: The quantitative analysis of electroencephalographic activity (EEG) is a useful tool for the study of changes in brain electrical activity during cognitive and behavioral functions in several experimental conditions. Their recording and analysis are currently carried out primarily through the use of computer programs. This paper presents a computerized program (EEGbands) created for Windows operating systems using the Delphi language, and designed to analyze EEG signals and facilitate their quantitative exploration. EEGbands applies Rapid Fourier Transformation to the EEG signals of one or more groups of subjects to obtain absolute and relative power spectra. It also calculates both interhemispheric and intrahemispheric correlation and coherence spectra and, finally, applies parametrical statistical analysis to these spectral parameters calculated for wide frequency EEG bands. Unlike other programs, EEGbands is simple and inexpensive, and rapidly and precisely generates results files with the corresponding statistical significances. The efficacy and versatility of EEGbands allow it to be easily adapted to different experimental and clinical needs.
RompecPC: A computerized program to create and solve jigsaw puzzles  [PDF]
Miguel Angel Guevara, Marai Pérez Hernández, Marisela Hernández González, Araceli Sanz-Martin, Sonia Ramírez Zapata
Journal of Biomedical Science and Engineering (JBiSE) , 2013, DOI: 10.4236/jbise.2013.67088
Abstract: RompecPC is a computerized program designed to create and assemble jigsaw puzzles. The program automatically records the solver’s responses as the number of pieces positioned correctly, the number of correct and incorrect movements, the number of times that she/he attempts to move a piece to the same place (perseverations), and the latency and place to which each piece is moved or attempted to be moved. These features facilitate the implementation and evaluation of puzzles while also reducing human error. Therefore, RompePC is a useful tool for the neuropsychological assessment of visuospatial skills in both clinical and experimental research.
Electroencephalographic Correlates of Sexual Arousal Induced by Sexually-Explicit Reading in Human Females  [PDF]
Miguel Angel Guevara, Carolina Gómez-Navarro, Claudia Amezcua-Gutiérrez, Marisela Hernández-González, Anders ?gmo
Journal of Behavioral and Brain Science (JBBS) , 2018, DOI: 10.4236/jbbs.2018.811037
Abstract: This study explored the cortical functionality in young women while reading a sexually-explicit text. Electroencephalographic activity (EEG) was recorded in heterosexual women while reading either a sexually-explicit text or one with neutral content. Absolute power (AP) and the degree of EEG synchronization among the prefrontal, temporal and parietal cortices were analyzed for the different EEG bands. To evaluate sexual arousal, valence and general activation, Likert-type and Manikin scales were applied. Subjects scored the sexually-explicit text as more pleasurable, and reported greater general activation and sexual arousal than while reading the neutral one. During reading of the sexually-explicit text only, they showed a higher AP in the beta and gamma bands in temporal areas in both hemispheres, and in the theta band in parietal ones, with a lower degree of EEG synchronization between prefronto-temporal areas in the fast bands. Results show that both hemispheres were activated in these sexually-aroused women. The low bilateral synchronization between prefrontal and temporal regions indicates the independent functionality of these cortices, which could be a requirement for inducing and maintaining sexual arousal during reading of sexually-explicit texts in women. These data should broaden our knowledge of the cortical mechanisms that underlie sexual arousal in women.
Ethanol Effects on Cortical EEG Correlation and Sexual Behavior in Male Rats  [PDF]
Miguel Angel Guevara, Marisela Hernández-González, Mayra Linné Almanza-Sepúlveda, Diego Radberto Chapa García Abascal, Pilar Durán, Carolina Sotelo Tapia, Fabricio Luna Torres
Journal of Behavioral and Brain Science (JBBS) , 2014, DOI: 10.4236/jbbs.2014.42012
Abstract: Ethanol affects sexual behavior drastically, as much as its execution as well as its motivation. Ethanol is a central nervous system depressant and the prefrontal cortex (PFC) is one of the cortical areas most sensitive to its effects. This prefrontal area participates in the modulation of the cognitive control, and furthermore, by mean of connections with the parietal cortex (PC) plays an important role in the processing of sexually relevant stimuli. Considering that it has been reported that the ethanol affects the proper functioning of these cortical areas, particularly decreasing the degree of electroencephalographic (EEG) coupling or correlation between them, the aim of this study was to characterize the effect of a low dose of ethanol on EEG correlation, as well determining if this effect is associated with impaired sexual behavior in male rats. Nine male rats unilaterally implanted were simultaneously recorded the EEG from the PFC and PC to calculate the degree of EEG synchronization (correlation, r) between both cortices during the first 40 minutes post administration of 0.75 g/kg of ethanol. At the end of the EEG recording, the males were submitted to copulatory behavior with a receptive female rat. The ethanol administration was associated with a decreased intrahemispheric correlation of the fast bands between PFC and PC, as well as with an increased mount and intromission latency. This data showed that ethanol in moderate doses decreased the coupling degree between cortices. It is likely that this functional disconnection between the PFC and PC after the ethanol administration could be associated with the difficulty in discriminating incentive value of the sexual stimuli so that decreased the sexual motivation but not the performance of the copulatory parameters in the male rat.
Prefrontal-Parietal Correlation during Performance of a Visuospatial Working Memory Task in Children, Adolescents and Young Adults  [PDF]
Miguel Angel Guevara, Jorge Carlos Hevia-Orozco, Araceli Sanz-Martin, Lucía Ester Rizo-Martínez, Marisela Hernández-González, Mayra Linné Almanza-Sepúlveda
Journal of Behavioral and Brain Science (JBBS) , 2015, DOI: 10.4236/jbbs.2015.510043
Abstract: Development of the prefrontal cortex and its connectivity with different cortical areas has strong implications for the improvement of working memory. The aim of this research was to characterize the interhemispheric (INTER) prefrontal and hemispheric (INTRA) frontopolar-dorsolateral prefrontal and dorsolateral prefrontal-parietal correlation (r) in children, adolescents and adults during performance of a visuospatial working memory task (VSWM). INTERr and INTRAr of 36 different aged male participants (11 - 13, 18 - 20 and 26 - 30 years old) were calculated during performance of the Corsi Block-Tapping task, which assessed VSWM. On this task, children showed lower correct responses than adolescents and adults. Adults also showed lower total execution times than children and adolescents, with a more efficient performance. On the EEGs, the older groups showed both higher interfrontal correlations and left and right prefronto-parietal correlations than children. According to our results, the progressive efficiency in VSWM is related to differences in EEG patterns among children, adolescents and adults.
Fiebre manchada de las monta?as rocosas: Informe de dos casos
Martínez-Medina, Miguel Angel;Padilla-Zamudio, Guillermo;Solís-Gallardo, Lilia Patricia;Guevara-Tovar, Marcela;
Gaceta médica de México , 2005,
Abstract: rocky mountain spotted fever (rmsf) is an acute febrile illness caused by infection with ricketsia rickettsii, characterized by the presence of petechial rash. even though the etiology, clinical characteristics and availability of effective antibiotics are known, rmsf related deaths have a prevalence of 4%. in its early stages rmfs can resemble many others infectious conditions and the diagnosis can be difficult. the present paper reports two patients with rmsf; these cases underscore the importance of prompt diagnosis and appropriate antimicrobial therapy, and consider rmsf as a differential diagnosis in any patient who develops fever and rash in an endemic area.
Senning operation for correction of the transposition of the great arteries, results, long-term outcome and quality of life  [PDF]
Miguel Angel Maluf
World Journal of Cardiovascular Diseases (WJCD) , 2012, DOI: 10.4236/wjcd.2012.23036
Abstract: Objective: Long-term results after the Senning operation for transposition of the great arteries are little known. Sinus node dysfunction and systemic ventricular dysfunction are crucial in patient survival. We evaluated the results, long term outcome and quality of life in a group of 39 patients. Methods: The study was a retrospective analysis, of 39 (39/40 = 97.5%) surgical surviving patients, submitted to Senning operation, with a mean follow-up time of 14.7 +/– 3.1 years. Electrocardiogram, echocardiogram, and chest radiograph series were performed every 6 months. Thirty six patients of this series underwent Holter study and ergometric test, to evaluate the physical capacity. Three patients living overseas were excluded. Results: There was only one late death (1/39) (late mortality = 2.5%): a 16 year-old patient had a no cardiac death. The actuarial survival was 95.0% (38/40) (simple or with little VSD, TGA). The probability of staying in sinus rhythm, in 39 surviving patients was 77.1% (30) or normal right ventricular function was 76.5% (29), 10 to 20 years after operation. The incidence of sinus node and right ventricular dysfunction increased gradually over time. No re-operations and pacemaker implantation, was performed. Functional class: I = 30 (85.7%) cases and functional class II = 5 (14.3%) cases. Conclusions: Patients with simple TGA submitted to Senning procedure in our experience, presented during late follow-up: 1—Low incidence of right ventricular dysfunction and active arrhythmias; 2—Low mortality and no sudden death recorded; 3—Good quality of life and 4—Satisfactory surgical results (free of re-operation or definitive pacemaker implantation).
The Accounting Analysis of Banking Company: The Case of CAM  [PDF]
Miguel Angel Perez Benedito
Modern Economy (ME) , 2015, DOI: 10.4236/me.2015.62015
Abstract: The measure of management risk has been a constant in Economy in the recent past. This issue is present on any kind of economic or financial activity. The solution adopted for international authorities, increasing liquidity of financial market and generating new indicators to support making decisions, means the continuity of applying the monetary theory as general criteria to solve the actual crisis. In this labyrinth, the manuscript uses the Accounting Methodology of Edgeworth’s Box as a new methodology to measure the management of Banking Companies and analyzes the acquisition of the CAM and Bank Sabadell, two Spanish banking companies. Finally, the manuscript analyzes the financial crisis in Spain through the behavior of listed banking companies in IBEX 35. The manuscript concludes that accounting can explain equilibrium in economy, and it only needs to know how they can be measured properly.
Accounting Analysis of Economic Policy of Spain (2012)  [PDF]
Miguel Angel Pérez Benedito
Theoretical Economics Letters (TEL) , 2014, DOI: 10.4236/tel.2014.43035
Abstract: The analysis of economic policy is made through a new methodology using the information provided by businesses to the Bank of Spain. The financial statements are the result of economic and financial transactions in a year and show a behavior that is likely to be measured by applying the Edgeworth’s box for analysis. This means that it is possible to measure the response of firms against market disruptions through an accounting interpretation of the information contained in the financial statements. The indicators obtained through this methodology measure a position taken in the Edgeworth’s box. Consequently, the observations obtained are random and therefore may explain the evolution of the economy of any country.
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