Analysis of antepartum cardiotocography based on S/k proportions and probability in 20 minutes / Análisis de la cardiotocografía anteparto mediante las relaciones S/k y la probabilidad en 20 minutos

Abstract Objectives: although mortality and perinatal asphyxia in newborns have been considerably reduced, there are still deficiencies in screening and diagnosis methods for intrapartum fetal well being that aim to detect its early alterations. Therefore, the purpose of this research was to apply a methodology based on probability and entropy and confirm its capacity to detect normal and abnormal fetal cardiac dynamics from 20-minute cardiotocographic tracings. Methods: 80 cardiotocographic tracings of pregnant women in the last trimester were collected, of which the minimum and maximum fetal heart rate were evaluated every 10 seconds, as well as its repetitions along with their probability and the diagnostic S/k ratio. Finally, the statistical analysis was carried out to establish the diagnostic capacity of the method concerning the clinical evaluation and interpretation of the cardiotocographic tracing, taken as the Gold Standard. Results: it was confirmed that S/k ratio values differentiated normal from abnormal fetal cardiac dynamics with sensitivity and specificity values of 100% and a Kappa coefficient of 1. Conclusion: the applicability of a diagnostic mathematical method of cardiotocography was confirmed, which suggests its implementation in the clinical context to detect alterations in fetal well-being in 20 minutes.

Resumo Objetivos: aunque se ha logrado reducir considerablemente la mortalidad y asfixia perinatal en neonatos, aún hay deficiencias en los métodos de tamizaje y diagnóstico del bienestar fetal intraparto que detecten sus alteraciones tempranas. Por lo anterior, el propósito de esta investigación fue aplicar una metodología basada en la probabilidad y la entropía y confirmar su capacidad para diagnosticar la dinámica cardíaca fetal normal de la anormal a partir de trazados cardiotocográficos de 20 minutos. Métodos: se recolectaron 80 trazados cardiotocográficos de gestantes en el último trimestre, de los cuales se evaluaron frecuencia cardíaca fetal mínima y máxima cada 10 segundos al igual que sus repeticiones, su probabilidad y la proporción S/k diagnóstica. Finalmente, se realizó un análisis estadístico para establecer la capacidad diagnóstica del método con respecto a la interpretación el trazado cardiotocográfico y la evaluación clínica, tomadas como Gold Standard. Resultados: se confirmó que los valores de la proporción S/k diferenciaron las dinámicas cardíacas fetales normales de las anormales con valores de sensibilidad y especificidad del 100% y un coeficiente Kappa de 1. Conclusión: se confirmó la aplicabilidad de un método matemático diagnóstico de la cardiotocografía, lo cual sugiere que su implementación en la clínica para detectar alteraciones del bienestar fetal en 20 minutos.

A heart sound classification method based on complete ensemble empirical modal decomposition with adaptive noise permutation entropy and support vector machine / 生物医学工程学杂志

Heart sound signal is a kind of physiological signal with nonlinear and nonstationary features. In order to improve the accuracy and efficiency of the phonocardiogram (PCG) classification, a new method was proposed by means of support vector machine (SVM) in which the complete ensemble empirical modal decomposition with adaptive noise (CEEMDAN) permutation entropy was as the eigenvector of heart sound signal. Firstly, the PCG was decomposed by CEEMDAN into a number of intrinsic mode functions (IMFs) from high to low frequency. Secondly, the IMFs were sifted according to the correlation coefficient, energy factor and signal-to-noise ratio. Then the instantaneous frequency was extracted by Hilbert transform, and its permutation entropy was constituted into eigenvector. Finally, the accuracy of the method was verified by using a hundred PCG samples selected from the 2016 PhysioNet/CinC Challenge. The results showed that the accuracy rate of the proposed method could reach up to 87%. In comparison with the traditional EMD and EEMD permutation entropy methods, the accuracy rate was increased by 18%-24%, which demonstrates the efficiency of the proposed method.

Research on Q-markers of Polygoni Perfoliati Herba based on analytic hierarchy process-entropy weight method and fingerprints / 中国中药杂志

The potential quality markers(Q-markers) of Polygoni Perfoliati Herba were studied based on analytic hierarchy process(AHP)-entropy weight method(EWM), network pharmacology, and spectrum-effect relationship analysis. The AHP-EWM was used for quantitative identification of the Q-markers. To be specific, AHP was applied for the weight analysis of the validity, testability, and specificity of the first-level indexes, and EWM for the analysis of the second-level indexes supported by literature and experimental data. Based on literature and network pharmacology, the validity analysis was to study the component-target-disease-efficacy network, and select the components with the strongest correlation with the efficacy of clearing heat and removing toxin, diuresis and alleviating edema, and relieving cough. For the testability analysis, the high performance liquid chromatography(HPLC) and literature research were used to determine the 10 components in Polygoni Perfoliati Herba, and the fingerprints of Polygoni Perfoliati Herba were established at the same time. The specificity analysis was based on the statistics of the number of plants in which the components existed. Thereby, the 11 compounds: quercetin, oleanolic acid, ellagic acid, gallic acid, kaempferol, rutin, esculetin, quercetin-3-O-glucuronide, ursolic acid, protocatechuic acid, and ferulic acid, were identified as potential Q-markers. The 11 compounds were identified to have high anti-inflammatory activity, indicating that the 11 Q-markers may be the functional material basis. The result in this study is expected to serve as a reference for the quality control of Polygoni Perfoliati Herba.

Research progress and application of transfer entropy algorithm / 生物医学工程学杂志

In recent years, exploring the physiological and pathological mechanisms of brain functional integration from the neural network level has become one of the focuses of neuroscience research. Due to the non-stationary and nonlinear characteristics of neural signals, its linear characteristics are not sufficient to fully explain the potential neurophysiological activity mechanism in the implementation of complex brain functions. In order to overcome the limitation that the linear algorithm cannot effectively analyze the nonlinear characteristics of signals, researchers proposed the transfer entropy (TE) algorithm. In recent years, with the introduction of the concept of brain functional network, TE has been continuously optimized as a powerful tool for nonlinear time series multivariate analysis. This paper first introduces the principle of TE algorithm and the research progress of related improved algorithms, discusses and compares their respective characteristics, and then summarizes the application of TE algorithm in the field of electrophysiological signal analysis. Finally, combined with the research progress in recent years, the existing problems of TE are discussed, and the future development direction is prospected.

Quantifying the state of cell differentiation based on the gene networks entropy / 生物工程学报

Studies of cellular dynamic processes have shown that cells undergo state changes during dynamic processes, controlled mainly by the expression of genes within the cell. With the development of high-throughput sequencing technologies, the availability of large amounts of gene expression data enables the acquisition of true gene expression information of cells at the single-cell level. However, most existing research methods require the use of information beyond gene expression, thus introducing additional complexity and uncertainty. In addition, the prevalence of dropout events hampers the study of cellular dynamics. To this end, we propose an approach named gene interaction network entropy (GINE) to quantify the state of cell differentiation as a means of studying cellular dynamics. Specifically, by constructing a cell-specific network based on the association between genes through the stability of the network, and defining the GINE, the unstable gene expression data is converted into a relatively stable GINE. This method has no additional complexity or uncertainty, and at the same time circumvents the effects of dropout events to a certain extent, allowing for a more reliable characterization of biological processes such as cell fate. This method was applied to study two single-cell RNA-seq datasets, head and neck squamous cell carcinoma and chronic myeloid leukaemia. The GINE method not only effectively distinguishes malignant cells from benign cells and differentiates between different periods of differentiation, but also effectively reflects the disease efficacy process, demonstrating the potential of using GINE to study cellular dynamics. The method aims to explore the dynamic information at the level of single cell disorganization and thus to study the dynamics of biological system processes. The results of this study may provide scientific recommendations for research on cell differentiation, tracking cancer development, and the process of disease response to drugs.

Diagnóstico matemático del infarto agudo de miocardio y de la falla cardiaca mediante la entropía proporcional / Mathematical Diagnosis of Acute Myocardial Infarction and Failure Using Proportional Entropy

Introducción: Las teorías físicas y matemáticas han permitido el desarrollo de nuevas metodologías diagnósticas de la dinámica cardiaca. Entre estas se encuentra la evaluación de las proporciones de la entropía proporcional para diferenciar la normalidad de la enfermedad cardiaca, aunque su capacidad diagnóstica debe comprobarse en escenarios clínicos críticos específicos, como en la falla cardiaca y el infarto agudo de miocardio. Objetivo: Describir evaluaciones diagnósticas de la dinámica cardiaca en pacientes con infarto agudo de miocardio o falla cardiaca aguda. Métodos: En un estudio a doble ciegos con 20 Holter, 5 normales, 8 con falla cardiaca aguda y 7 con infarto agudo de miocardio, se aplicó un método fundamentado en las proporciones de la entropía tomando los valores máximos y mínimos de la frecuencia cardiaca y el número total de latidos por hora, en un mínimo de 18 horas, generando un atractor numérico. Se evaluó cada dinámica con base en la entropía y sus proporciones. Finalmente, se comparó la precisión diagnóstica del método matemático con respecto al diagnóstico clínico convencional. Resultados: Se diferenciaron matemáticamente los casos normales y patológicos mediante la evaluación en 18 horas con el método descrito, encontrando valores de sensibilidad y especificidad del 100 por ciento y un coeficiente Kappa de uno, indicando una concordancia diagnóstica perfecta del método matemático con respecto al diagnóstico clínico. Conclusiones: Las proporciones de la entropía permiten establecer diagnósticos objetivos de la dinámica cardiaca, diferenciando matemáticamente dinámicas normales de aquellas que presentan infarto agudo de miocardio y falla cardiaca aguda(CU)

Introduction: Physical and mathematical theories have allowed the development of new diagnostic methodologies of cardiac dynamics, as one based on the evaluation of entropy proportions to differentiate normality from cardiac disease, although its diagnostic capacity must be yet determined in specific critical scenarios as acute heart failure and acute myocardial infarction Objective: To describe diagnostic evaluations of cardiac dynamics in patients diagnosed with acute myocardial infarction or acute heart failure. Methods: A blind study was developed with 20 Holter registries; 5 normal, 8 with acute cardiac failure and 7 with acute myocardial infarction. Then, a method based on the proportions of the entropy of the numerical attractors was applied. The maximum and minimum values of the heart rate and the total number of beats per hour were taken for at least 18 hours, with which numerical attractors were generated, which measure the probability of consecutive heart rate pairs. An evaluation of all dynamics was made based on the entropy and its proportions. Finally, a comparison between the diagnostic precision of the mathematical method with respect to the conventional clinical diagnosis was performed. Results: Normal cases were mathematically differentiated from the pathological ones through the evaluation of Holter registries for 18 hours, achieving values of sensitivity and specificity of 100 percent as well as a Kappa coefficient of 1, indicating a perfect diagnostic concordance between the mathematical method to diagnose the cardiac dynamics with respect to the clinical diagnosis. Conclusions: The proportions of entropy allow to establish objective diagnoses of cardiac dynamics, mathematically differentiating normal dynamics from those with acute myocardial infarction and with acute cardiac failure(AU)

Performance Appraisal of Select Nations in Mitigation of COVID-19 Pandemic using Entropy based TOPSIS Method / Avaliação de desempenho de nações selecionadas na mitigação de pandemia de COVID-19 usando método TOPSIS baseado em entropia

Abstract The present study was an effort to assess the mitigation interventions carried out, so far, by the nations to fight the pandemic COVID-19. The novelty of the study was that it had considered the issue of pandemic mitigation strategy as a decision making problem. The performances of the twenty nations were to be ranked. The problem considered in the study was essentially a Multi-Criteria Decision Analysis (MCDA) problem. The available alternatives were the 20 countries and the 8 traits were the criteria. The Technique of Order Preference Similarity to the Ideal Solution (TOPSIS) was used in the present study. The study used Entropy method for assignment of weights to all the criteria. The performance score obtained in respect of the countries considered in the study and the corresponding ranks indicated the relative performances of the countries in their efforts to mitigate the COVID-19 pandemic. The results show that New Zealand is the best performing country and India is the worst one. Brazil ranked 17th, while the rank of UK was 15. The performance of the USA stood at 18th position.

Resumo O presente estudo foi um esforço para avaliar as intervenções de mitigação realizadas, até o momento, pelas nações para combater a pandemia COVID-19. A novidade do estudo é que considerou a questão da estratégia de mitigação da pandemia como um problema de tomada de decisão. As performances das vinte nações deveriam ser classificadas. O problema considerado no estudo era essencialmente um problema de Análise de Decisão Multi-Critério (MCDA). As alternativas disponíveis eram os 20 países e as 8 características eram os critérios. A Técnica de Similaridade de Preferência de Pedido com a Solução Ideal (TOPSIS) foi utilizada no presente estudo. O estudo utilizou o método da Entropia para atribuição de pesos a todos os critérios. A pontuação de desempenho obtida em relação aos países considerados no estudo e as classificações correspondentes indicaram os desempenhos relativos dos países em seus esforços para mitigar a pandemia COVID-19. Os resultados mostram que a Nova Zelândia é o país com melhor desempenho e a Índia o pior. O Brasil ficou em 17º, enquanto o Reino Unido ficou em 15. O desempenho dos EUA ficou na 18ª posição.

Optimized multi-scale entropy to localize epileptogenic hemisphere of temporal lobe epilepsy based on resting-state functional magnetic resonance imaging / 生物医学工程学杂志

Entropy model is widely used in epileptic electroencephalogram (EEG) analysis, but there are few reports on how to objectively select the parameters to compute the entropy model in the analysis of resting-state functional magnetic resonance imaging (rfMRI). Therefore, an optimization algorithm to confirm the parameters in multi-scale entropy (MSE) model was proposed, and the location of epileptogenic hemisphere was taken as an example to test the optimization effect by supervised machine learning. The rfMRI data of 20 temporal lobe epilepsy (TLE) patients with hippocampal sclerosis, positive on structural magnetic resonance imaging, were divided into left and right groups. Then, the parameters in MSE model were optimized by the receiver operating characteristic curves (ROC) and area under ROC curve (AUC) values in sensitivity analysis, and the entropy value of the brain regions with statistically significant difference between the groups were taken as sensitive features to epileptogenic hemisphere lateral. The optimized entropy values of these bio-marker brain areas were considered as feature vectors input into the support vector machine (SVM). Finally, combining optimized MSE model with SVM could accurately distinguish epileptogenic hemisphere in TLE at an average accuracy rate of 95%, which was higher than the current level. The results show that the MSE model parameter optimization algorithm can accurately extract the functional imaging markers sensitive to the epileptogenic hemisphere, and achieve the purpose of objectively selecting the parameters for MSE in rfMRI, which provides the basis for the application of entropy in advanced technology detection.

Research on Q-markers of Eupatorium lindleyanum based on analytic hierarchy process-entropy weight method and network pharmacology / 中国中药杂志

The potential quality markers( Q-markers) of Eupatorium lindleyanum were studied with analytic hierarchy process(AHP)-entropy weight method(EWM) and network pharmacological method. Based on the concept of Q-markers of traditional Chinese medicine, AHP-EWM was employed to quantitatively identify the Q-markers of E. lindleyanum. AHP method was applied to the weight analysis of the validity, testability, and specificity of the first-level indexes, and EWM method was used to analyze the secondlevel indexes supported by literature and experimental data. At the same time, based on the theory and method of network pharmacology, the component-target-disease-efficacy network of E. lindleyanum was built, and the components most closely related to the efficacy of resolving phlegm and relieving cough and asthma were screened out. Through the integrated analysis of the results obtained with AHP-EWM and network pharmacological method, 13 compounds including rutin, quercetin, nepetin, cirsiliol, luteolin, hyperoside,isoquercitrin, kaempferol, caffeic acid, eupalinolide K, eupalinolide A, eupalinolide B, and eupalinolide C were comprehensively identified as the potential Q-markers of E. lindleyanum. The results provide a basis for the quality control of E. lindleyanum.

Comparative analysis and research on composition of mulberry-sourced medicinal materials by fingerprint division total statistical moment method and information entropy / 中国中药杂志

The present work is to analyze the HPLC fingerprints of mulberry-sourced materials(Mori Ramulus, Mori Folium, Muri Cortex, Mori Fructus) using the fingerprint division total statistical moment method and information entropy, and to study the diffe-rences of the chemical components and the overall characteristics of the imprinting template in different parts of mulberry-sourced medicinal materials, so as to provide the basis for finding the effective substances in response to "homologous and different effect" of mulberry(Morus alba). The fingerprints of 24 batches of mulberry-related materials, such as Mori Ramulus, Mori Folium, Muri Cortex, Mori Fructus, were established, and the similarities and differences of the fingerprints were analyzed by calculating the division total statistical moment parameters and information entropy. The AUC_T, MCRT_T, VCRT_T and H values of 24 batches of mulberry-sourced materials were less than 0.05, with significant difference. Among them, all samples showed absorption peaks within 3-11, and 20-24 min, indicating that the four types had the identical or similar chemical composition in the same time period. After 34 min, none of the four types showed absorption peaks. Greater VCRT_T value of the fingerprints of the four kinds was observed at the retention time ranges of 3-4, 16-18, 25-27, and 31-32 min, indicating that the components of the four kinds were significantly different in these time periods; and VCRT_T value of the mulberry was significantly higher than that of the other three kinds of medicinal materials at the retention time windows of 3-4 and 15-17 min; the VCRT_T value of the mulberry white skin was significantly higher at the time windows of 8-10 and 28-30 min; the VCRT_T value of all four kinds was significantly higher within 21-23 min, indicating that the four herbs contain the same or similar components in the chromatogram during this period, but there may be significant differences between the content and the proportion. In addition, the information entropy of mulberry branches is the largest at 7-12, 23-27 min, and that of mulberry fruits is the largest at 2-8 min, which indicates that the components of mulberry branches and mulberry fruits respond greatly in the corresponding period of time, which is also the main peak period of their chemical components. For the chemical components and corresponding efficacy here. The results showed that there are significant differences in the components and contents of mulberry-sourced medicinal materials. The division total statistical moment and information entropy of the total amount of segments can be used to analyze the differences in the components of "homology and different effects", which could provide a more comprehensive analysis method for the determination of quality markers.

Quality evaluation of Saposhnikoviae Radix based on QAMS combined with information entropy-response surface method / 中国中药杂志

This research was used with high performance liquid chromatography(HPLC), combined with information entropy-response surface method(RSM) to investigate the ethanol concentration, extraction time, liquid-to-material ratio. Taking the content of four chromogens as evaluation indexes, the weight coefficients of each index were given, and the comprehensive score was calculated to optimize the extraction process. Then, prim-O-glucosylcimifugin was used as the reference, the relative calibration factors(RCFs) of cimifugin, 4'-O-β-D-glucosyl-5-O-methylvisamminol and sec-O-glucosylhamaudo to prim-O-glucosylcimifugin were calculated respectively. The contents of four components in Saposhnikoviae Radix were determined by both external standard method(ESM)and quantitative analysis of multi-components by single marker(QAMS) method, and the results were compared. At last, combined with principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) to evaluate the quality of the Saposhnikoviae Radix in different production areas. The optimal extraction process parameter of the Saposhnikoviae Radix was as follows: liquid-to-material ratio is 60∶1(mL·g~(-1)), extraction time is 35 min, and ethanol concentration is 70%. The repeatability of the RCFs was perfect, and the results calculated by the QAMS were consistent with the results from the ESM. The stoichiometric results indicate that there are obvious differences in the distribution of Saposhnikoviae Radix in different production areas, and cimifugin and prim-O-glucosylcimifugin are the characteristic compounds that cause this difference. In this study, the optimal extraction process is stable and feasible, and the method of QAMS is accurate and reliable. From the perspective of four chromogens, there are differences in the quality of the Saposhnikoviae Radix in different production areas. Therefore, the established extraction process combined with the method of QAMS can be used to evaluate the quality of Saposhnikoviae Radix and provide a scientific basis for the quality control of Saposhnikoviae Radix.

Identification of quality markers of Qixuehe Capsules based on analytic hierarchy process and entropy weight methods / 中国中药杂志

Qixuehe Capsules is a compound Chinese patent medicine developed for treating the disorder of Qi and blood(a common etiology of gynecological disease), which has remarkable effects on smoothing liver and regulating Qi, activating blood circulation, and relieving pain. However, due to its complex prescriptions(15 herbs) and multiple effects, the quality control of Qixuehe Capsules has always been a bottleneck problem limiting its sustainable development. Therefore, this study adopted the traditional Chinese medicine Q-markers quantitative identification system established previously by our research group based on the combination of analytic hierarchy process and entropy weight methods. With the different effects of Qixuehe Capsules as the entry point, the comprehensive scores of chemical ingre-dients in Qixuehe Capsules under the items of effectiveness(smoothing liver and regulating qi, activating blood circulation, and relieving pain), testability and specificity were calculated and integrated, respectively. Subsequently, through the analysis of compatibility relationship of Qixuehe Capsules, 15 active ingredients with high comprehensive scores were found to be the top Q-mar-kers of Qixuehe Capsules, including ferulic acid, quercetin, caffeic acid, kaempferol, rutin, Z-ligustilide, senkyunolide Ⅰ, vanillic acid, protocatechuic acid, chlorogenic acid, rosmarinic acid, senkyunolide A, gallic acid, tetrahydropalmatine and eugenol. Collectively, this study not only provided scientific evidence for further research on the improvement and standardization of quality standards of Qixuehe Capsules but also provided methodological references for the quantitative identification of Q-markers of multi-effect traditional Chinese medicine formulae.

Comprehensive antioxidant and anti-inflammatory activity of alcohol extracts from Chrysanthemum indicum in different areas based on entropy weight and TOPSIS methodology / 中国中药杂志

The study is aiming at investigating the application of entropy weight TOPSIS method in the comparison of the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) of Chrysanthemum indicum. The DPPH, ABTS, salicylic acid and spectrophotometry were used to determine the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) of Ch. indicum from 31 different areas in vitro. Take the half inhibition rate of as the evaluation index, two principal components were extracted by the principal component analysis, and their cumulative contribution rate reached at 92.4%. The different areas of Ch. indicum could be divided into Dabei Mountain and Qinling-Taihang Mountain by use principal component to analysis. The entropy weight TOPSIS method was used to objectively assign weights to five indexes, calculate the weight of each index and set up the best and worst scheme of the evaluation object, and the relative proximity(C_i) was used as the measure to construct the multi-index comprehensive evaluation model of Ch. indicum. And then sort with the relative proximity value. The results showed that the relative proximity was between 0.098 and 0.983 which represents there were significant differences in the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) between extracts of Ch. indicum from different areas. The Ch. indicum from Dabie Mountain area have a relatively high relative degree of measurement and high-quality ranking. Taken together, the quality of Ch. indicum.from the Dabie Mountain area is better. The index weight coefficient and the classification result of producing area are basically consistent with the result of principal component analysis. The results show that the TOPSIS method based on entropy weight method can be used to evaluate the comprehensive quality of Ch. indicum.

Variability of anesthetic depth in total intravenous anesthesia vs balanced anesthesia using entropy indices: a randomized, crossover, controlled clinical trial / Variabilidad de la profundidad anestésica en anestesia total intravenosa vs. anestesia general balanceada usando índices de entropía. Un ensayo clínico aleatorizado, cruzado y controlado

Abstract Introduction: Total intravenous anesthesia (TIVA) and balanced anesthesia (BA) are the most commonly used anesthetic techniques. The differences are the variability of the depth of anesthesia between these techniques that might predict which one is safer for patients and presents a lower risk of intraoperative awakening. Objective: To determine whether a difference exists in the variability of depth of anesthesia obtained by response entropy (RE). Methods: A crossover clinical trial was conducted on 20 healthy patients receiving upper or lower limb ambulatory orthopedic surgery. Patients were randomly assigned to (a) target-controlled infusion of propofol using the Schnider model at a target concentration of 2.5 µg/mL for 15 minutes and a 10-minute washout, followed by sevoflurane administration at 0.8 minimal alveolar concentration (MAC) for the reminder of the surgery, or (b) the reverse sequence. Differences in the variability of the depth of anesthesia using RE were evaluated using paired t-test. Results: The treatment effect showed no significant difference in the average values of RE, during TIVA = 97.23 vs BA 97.04 (P = 0.39). Carry Over (-4.98 vs 4.08) and Period (100.3 vs 94.68) effects were not significantly different. Conclusion: The present study suggests that both anesthetic techniques are equivalent in terms of the stability of the depth of anesthesia. It is important to keep testing the determinants of the efficacy of different populations because the individual behaviors of patients might ultimately tip the scale.

Resumen Introducción: La anestesia total intravenosa (TIVA, por sus siglas en inglés) y la anestesia balanceada (AB) son las técnicas anestésicas más comúnmente utilizadas. La diferencia está en la variabilidad de la profundidad de la anestesia entre estas dos técnicas, lo cual pudiera predecir cuál es más segura para los pacientes y representar un menor riesgo de despertar intraoperatorio. Objetivo: Determinar si existe alguna diferencia en la variabilidad de la profundidad de la anestesia obtenida según los índices de entropía de respuesta (ER). Métodos: Se llevó a cabo un estudio clínico cruzado en 20 pacientes sanos que se sometieron a cirugía ortopédica ambulatoria de miembros superiores o inferiores. Los pacientes se asignaron aleatoriamente así: a) infusión controlada por objetivo (TCI, por sus siglas en inglés) de propofol, utilizando el modelo Schnider a una concentración objetivo de 2,5 µg/mL durante 15 min y un período de lavado de 10 minutos, seguido de la administración de sevoflurano a 0,8 de concentración alveolar mínima (CAM) durante el tiempo restante de la cirugía; o b) la secuencia inversa. Las diferencias en la variabilidad de la profundidad de la anestesia utilizando entropía de respuesta se evaluaron utilizando la prueba t pareada. Resultados: El efecto del tratamiento no mostró ninguna diferencia significativa en los valores promedio de entropía de respuesta (ER) durante TIVA = 97,23 vs. AB 97,04 (P = 0,39). Los efectos de arrastre (-4,98 vs. 4,08) y período (100,3 vs. 94,68) no fueron significativamente diferentes. Conclusiones: El presente estudio sugiere que ambas técnicas anestésicas son equivalentes en términos de estabilidad de la profundidad de la anestesia. Es importante continuar probando los factores determinantes de eficacia en las distintas poblaciones, ya que el comportamiento individual de cada paciente pudiera finalmente inclinar la balanza.

Ecology suitability study of Polygonatum cyrtonema / 中国中药杂志

Using the 260 geographical distribution records of Polygonatum cyrtonema in China, combined with 53 environmental factors, the maximum entropy modeling(MaxEnt) was used to study the ecological factors affecting the suitability distribution of P. cyrtonema. The ArcGIS software was used to predict the potential distribution of the population of P. cyrtonema. The dominant factors were chosen by using the Jackknife test and the Receiver Operating Characteristic(ROC) curve was used to evaluate the simulation. The results showed that high value of area under curve(AUC) denoted good results, which significantly differed from random predictions. Based on the evaluation criterion, the accuracies of the predictions of P. cyrtonema potential distribution in the current periods were excellent. The main environmental factors affecting the suitable growth of P. cyrtonema were the monthly precipitation, the wettest monthly precipitation, the annual average temperature range and the precipitation of November, March, February, April, May and October. There are 9 environmental factors in soil type. The potential fitness of P. cyrtonema in China is high, mainly concentra-ted in Hunan, western Hubei, Guangdong, northeastern Guangxi, southeastern Guizhou, Jiangxi, southwestern Anhui, Fujian, Zhejiang, Shaanxi, southwestern Henan and Chongqing. The growth distribution of the potential distribution area of P. cyrtonema was divided, and the zoning map of the growth suitability of P. cyrtonema was formed. Through the comparative analysis of the potential distribution range based on MaxEnt and the distribution range of literature records, the understanding of the distribution range of P. cyrtonema was expanded.

Multi-index optimization of extraction process of Fengyin Decoction based on BAS-GA-BP neural network combined with entropy weight method / 中国中药杂志

To optimize the ethanol extraction technology parameters of Fengyin Decoction by orthogonal experiment combined with beetle antennae search(BAS)-genetic algorithm(GA)-back propagation neural network(BPNN). Based on single factor investigation, the extraction temperature, ethanol volume, extraction time, and ethanol concentration were used as orthogonal experiment factors, and entropy weight method was used to calculate the comprehensive scores of aloe-emodin, glycyrrhizic acid ammonium salt, rhein, emodin, chrysophanol, physcion, cinnamaldehyde, 6-gingerol, extraction ratio and fingerprint similarity. BAS-BPNN model was established, and then, GA was used to predict the optimal extraction process. The results showed that BAS-BPNN was optimized to obtain the optimal ethanol extraction process of Fengyin Decoction as follows: extraction temperature of 87 ℃, adding 9 times of 75 % ethanol, and extracting for 47 minutes, with a comprehensive score of 1.052 9. Meanwhile, the optimal process parameters obtained by orthogonal design were as follows: the extraction temperature of 80 ℃, adding 10 times of 75% ethanol, extracting for 30 minutes, with a comprehensive score of 1.003 7. The comprehensive score of the process obtained from the BAS-BPNN model was slightly better than that from the orthogonal test, indicating that the optimized process from BAS-BPNN model was more ideal, so it was finally determined as the best extraction process for Fengyin Decoction. The process of Fengyin Decoction obtained from BAS-GA-BPNN has high extraction efficiency and good stability, which provides reference for the subsequent development and quality control.

Application research of entropy weight-based grey systematic theory in quality evaluation of Angelicae Sinensis Radix slices / 中国中药杂志

In order to discuss the "entropy weight method" for weighting various indicators in the comprehensive evaluation of Angelicae Sinensis Radix slices(ASR), the quality of ASR was comprehensively evaluated by entropy weight-based gray systematic theory and cluster analysis. In this study, the contents of ferulic acid, volatile oil, polysaccharide, alcohol extract, water extract, moisture, total ash and acid-insoluble ash in 44 batches of ASR from different sources were determined. The entropy weight method was used for objective weighting. With relative correlation(r_i) as a measure, a multi-index comprehensive evaluation model was constructed for the quality of ASR. The results showed that the relative correlation value of 44 batches of ASR ranged from 0.301 9 to 0.662 9. There were certain differences in the quality of ASR from different sources. The ASR S1-S8, traceable and standardized in processing techno-logy, showed a high relative correlation degree and high quality ranking, indicating that the implementation of systemic management of the production chain of Chinese herbal pieces was beneficial to the quality control of ASR. The quality evaluation results of 44 batches of ASR were consistent with those of traditional geo-authentic habitats for ASR and the mainstream varieties of ASR on market, and basically consistent with the results of cluster analysis. This study suggests that the gray systematic theory based on the entropy weighting method can be used for the quality evaluation of ASR. The objective weighting of the entropy weight method improves the reliability of the gray correlation method and the scientificity of ASR quality evaluation.

Retinal Vessel Segmentation Based on Multiscale Matched Filtering / 中国医疗器械杂志

Retinal vascular function is complex, morphological structure varies from person to person, and is susceptible to vascular diseases and systemic vascular diseases. Its accurate segmentation is of great significance for disease diagnosis and identification. In this paper, a multi-scale matching filtering algorithm is proposed for the uneven size of retinal blood vessels. On the basis of the traditional singlescale Gaussian matching filter, multiscale Gaussian matched filters with two sizes are used to enhance grayscale images. Enhancement is performed, and the superimposed image is binarized using a twodimensional maximum entropy threshold segmentation algorithm. The algorithm is tested in the DRIVE database with sensitivity, specificity and accuracy of 0.803, 0.959, 0.981, respectively. Comparing with the traditional algorithm, the algorithm has high sensitivity, fast running speed and rich details of segmentation results.

Evaluation of cardiac autonomic modulation using symbolic dynamics after cardiac transplantation

Abstract Objective: To characterize the behavior of cardiac autonomic modulation in individuals with different times after orthotopic heart transplantation (HTx) using symbolic dynamics analysis. Methods: Sixty patients were evaluated after HTx. We recorded their instantaneous R-R intervals (RRi) by cardiac monitor Polar® RS800CX™ (Polar Electro Oy, Kempele, Finland) for 10 minutes. The same sequence of RRi with 256 consecutive beats was used to perform spectral analysis and symbolic dynamics analysis. We used hierarchical clustering to form groups. One-way analysis of variance (ANOVA) (with Holm-Sidak method) or one-way Kruskal-Wallis test (with Dunn´s post-hoc test) was used to analyze the difference between groups. Linear correlation analysis between variables was performed using Pearson's or Spearman's tests. P-value < 0.05 was considered statistically significant. Results: The 0V% index increased, the 2UV% index and the normalized complexity index decreased with an increase of HTx postoperative time. There were a negative correlation between complexity indexes and 0V% and a positive correlation between complexity indexes and 2UV%. Conclusion: Symbolic dynamics indexes were able to show a specific cardiac autonomic modulation pattern for HTx recipients with different postoperative times.

¿Por qué emplear el análisis estadístico implicativo en los estudios de causalidad en salud? / Why Use the Implicative Statistical Analysis in Studies of Health Causality?

El análisis estadístico implicativo es una técnica de minería de datos, surgida para resolver problemas de la didáctica de las matemáticas, se basa en la inteligencia artificial y el álgebra booleana, para modelar la casi implicación entre eventos y variables de un conjunto de datos. El objetivo de este ensayo es exponer las evidencias teóricas y prácticas que demuestran su utilidad para el estudio de la causalidad en la salud, para lo cual se realizó una revisión exhaustiva del tema en las bases de datos bibliográficas alojadas en Internet. Se presentan una serie de razones que justifican el uso de esta técnica en estudios de causalidad en medicina, en relación con el número de variables, el tamaño de la muestra, los supuestos requeridos para su aplicación y la naturaleza asimétrica de sus índices. También se identifican algunas ventajas con respecto a las técnicas estadísticas tradicionales, como la detección de eventos raros, que pasan inadvertidos a medidas como el apoyo y la confianza. Finalmente, se mencionan las investigaciones clínico-epidemiológicas donde se ha utilizado este análisis(AU)

Implicative statistical analysis is a technique of data mining, emerged to solve problems of the Didactic of mathematics, it is based on Artificial Intelligence and Boolean Algebra, to model the quasi-implication between events and variables of a data set. The objective of this essay is to expose the theoretical and practical evidences that demonstrate its utility for the study of causality in health, for which an exhaustive review of the subject was carried out in the bibliographic databases hosted on the internet. A series of reasons are presented that justify the use of this technique in causality studies in medicine, regarding the number of variables, the sample size, the assumptions required for its application and the asymmetric nature of its indices. Also some advantages are identified with respect to traditional statistical techniques such as detection of rare events, which would go unnoticed to measures such as support and trust. Finally, clinical-epidemiological investigations where this analysis has been used are mentioned(AU)