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The aim of this study was to evaluate, for the first time, the antiproliferative, apoptotic and diminishing effects of the anchored growth-independent capacity of an ethanol macerate extract from the Annona cherimola seed (EMCHS) in the human gastric cancer cell line SNU-1. The cells treated with EMCHS (20 µg/mL) significantly reduced the capacity to form clones of the tumor cell. Moreover, 50 µg/mL of EMCHS extract induced apoptosis, as was shown by the Annexin-V assay. UHPLC-MS/MS analysis detected two acetogenins (Annonacinone and Annonacin) in the EMCHS, which could be largely responsible for its selective antiproliferative effect. The identification of fatty acids by GC-FID showed the presence of eight fatty acids, among which was, oleic acid, which has recognized activity as an adjuvant in antitumor treatments. Taken together, our results indicate that the EMCHS seems promising for use as a natural therapy against gastric cancer disease.

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Distorted voltage supplied as unbalanced and/or non-constant frequency can be found in weak grids, such as microgrids, or systems working in islanding mode. These kinds of systems are more sensitive under load changes. Particularly, an unbalanced voltage supply may be produced for large, single-phase loads. On the other hand, the connection/disconnection of high current loads may lead to important frequency variation, especially in weak grids where the short circuit current capacity is reduced. These conditions make the control of the power converter a more difficult task, because of the variations in the frequency and unbalancing. To address these issues, this paper proposes a resonant control algorithm to deal with variations in the voltage amplitude as well as grid frequency when a distorted power supply is considered. The frequency variation is an important drawback for resonant control because the resonance must be tuned at the grid frequency. This issue is overcome by using a variable sampling frequency in order to avoid re-tuning the controller parameters. On the other hand, under unbalanced conditions, the proposed method relaxes the phase with lower voltage amplitude by taking more power from the other phases in order to help the stability of the grid supply. To corroborate the mathematical analysis and the proposed control, a stability study is performed, including experimental and simulated results.

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Internet of Things (IoT) technologies allow building a digital representation of people, objects, or physical phenomena to be available on the Internet. Thus, stakeholders can access this information from remote places or computational systems could analyze this data to find patterns, make decisions, or execute actions. For instance, a doctor could diagnose patients by analyzing the received data from an IoT system even when patients are located in a remote place. This article proposes an IoT system for monitoring electrocardiogram (ECG) signal and processing heart data in order to generate an alert when an arrhythmia is present. This system involves a Polar H10 heart sensor, machine-learning models to classify heart events, and communication technology to share and store patient's information. In the first place, the architecture of the IoT monitoring system and the communication between the components are described by discussing the designing criteria. Second, the experimentation process performs the training and the assessment of three classification algorithms, random forest, convolutional neural network, and k-nearest neighbors. The results show that k-nearest neighbor has the best accuracy percentage classifying the arrhythmias under study (premature ventricular contraction 94%, fusion of ventricular beat 81%, and supraventricular premature beat 82%); also, it is able to discern normal and unclassifiable beats with 93% and 97%, respectively.

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Annona cherimola is a tree belonging to the family Annonacea, whose fruit (cherimoya) is very desirable, but its seeds are considered waste. Present in these seeds are compounds that have been described as selective antiproliferative agents for cancer cells. The aim of this study was to evaluate the antiproliferative activity of ethanol macerate extract (EMCHS) obtained from A. cherimola seeds against the human stomach gastric adenocarcinoma (AGS) cell line and the normal human gastric epithelial cell line (GES-1). The EMCHS extract presented an IC50 of 80.43 µg/mL in AGS cells, and a selectivity index (SI) of 3.5-fold higher than that of cisplatin. In addition, the EMCHS extract showed apoptotic activity in AGS cells since 50 µg/mL. Overxpression of PUMA gene in both cells demonstrate that EMCHS activate the apoptotic route. Future studies should be carried out to elucidate anticancer activity of EMCHS in vivo. This work represents the first showing antiproliferative effects of crude extracts obtained from seeds of A. cherimola in AGS cells.

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Este estudio describe el comportamiento de la Variabilidad de la Frecuencia Cardíaca (VFC) en los dominios de tiempo y frecuencia con relaciónal nivel de Actividad Física, medido mediante el Cuestionario Mundial para Actividad Física (GPAQ). Se estudiaron 20 aprendices de género masculino, con promedios de edad 21,47 +3,36 años y peso 61,09 +7,30 Kg, categorizados en nivel de actividad física alto y moderado, según criterios de la Organización Mundial de la Salud, en un rango de peso normal, Índice de Masa Corporal de 21,18 +1,99 Kg/m2, no fumadores, a quienes se les realizó una historia clínica que descartó enfermedad aparente al examen clínico y se les midió la VFC en reposo. Se utilizaron Cardiofrecuenciómetros marca POLAR®. A través de la t-student y pruebas de correlación se realizó el tratamiento estadístico de los datos. Los resultados evidencian una co- rrelación significativa entre la VFC y el grupo de Actividad Física ALTA. La correlación más alta se encontró en el dominio de frecuencia, entre el logaritmo de Baja Frecuencia y el grupo Actividad Física ALTA (r=0,747). Las variables en dominio tiempo mostraron correlaciones moderadas (R-Ri r= 0,57, rMSSD r= 0,665), así como en el análisis no-lineal, la SD1 en la gráfica de Poincaré (r=0,665). Se concluye que la VFC es un instrumento útil, de bajo costo, no invasivo, de fácil aplicación y que tiene una significativa correlación con el nivel de actividad física en adultos jóvenes sanos. Son necesarios otros estudios para dilucidar los multivariados factores que inciden en la VFC.

This assay describes the Heart Rate Variability (VFC) behavioral in time and frequency domains related with de Physical Activity level, measured by means of the Global Physical Activity Questioner (GPAQ). Twenty male non smokers students were studied, with an average age of 21,47 + 3,36, an average weight of 61,09 + 7,30 Kg, with a Body Mass Rate of 21,18+ 1,99 Kg/m2, categorized in high, medium or low Physical Activity Level according to the GPAQ questioner. Evident illnesses were dismissed by a clinical exam, and the HRV was measured on rest. The equipments used were hearth rate monitors scale trademark POLAR. Parametric criteria were used for the data analysis, the t-student and correlation tests were applied. The results show a significant correlation between the (VFC) and the High Physical Activity group. The highest correlation was found in the frequency domain, between the logarithm of the Low Frequency (LnBF by its initials in Spanish) and the group High Physical Activity group (A.F.ALTA, by its initials in Spanish, r= 0,747). The variables in the domain showed moderated correlations (R-Ri r= 0,57, rMSSD r= 0,665), the same as the non-linear analysis, the SD1 in the Poincar‚ plot (r=0,665). In conclusion, the Heart Rate Variability (VFC) is a low cost useful tool, non invasive and of easy application, which has a significant correlation with the level of physical activity in young healthy and non obese adults. More studies are necessary in order to elucidate the diverse factors that fall upon the Heart Rate Variability.

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