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1.
Chinese Journal of Epidemiology ; (12): 1310-1313, 2019.
Article in Chinese | WPRIM | ID: wpr-796777

ABSTRACT

At present, traditional methods on statistics have limitations in controlling time- varying confounding. This paper introduces an analysis method, parametric g-formula, which would adjust time-varying confounding, and also exemplifies the steps of its implementation for purpose to provide a new reference for researchers to deal with long-term observational data.

2.
Journal of Biomedical Engineering ; (6): 518-523, 2018.
Article in Chinese | WPRIM | ID: wpr-687600

ABSTRACT

The directed functional connectivity in cerebral cortical is the key to understanding the pattern of the behavioral tissue. This process was studied to explore the directed functional network of rifle shooters at cerebral cortical rhythms from electroencephalogram (EEG) data, aiming to provide neurosciences basis for the future development of accelerating rifle skill learning method. The generalized orthogonalized partial directed coherence (gOPDC) algorithm was used to calculate the effective directed functional connectivity of the experts and novices in the pre-shot period. The results showed that the frontal, frontal-central, central, parietal and occipital regions were activated. Moreover, the more directed functional connections numbers in right hemispheres were observed compared to the left hemispheres. Furthermore, as compared to experts, novices had more activated regions, the stronger strength of connections and the lower value of the global efficiency during the pre-shot period. Those indirectly supported the conclusion that the novices needed to recruit more brain resources to accomplish tasks, which was consistent with "neural efficiency" hypothesis of the functional cerebral cortical in experts.

3.
Rev. biol. trop ; 64(2): 571-585, abr.-jun. 2016. tab, ilus
Article in English | LILACS | ID: biblio-843299

ABSTRACT

AbstractAnts have been considered useful for bioindication because of their ecological characteristics. Nonetheless, among the characteristics of a bioindicator group, there must be a consistent and replicable response to disturbance. In this sense, divergent reactions have been found, even between taxons narrowly related. The objective of this work was to compare the diversity of the ant communities in three different temperate forests with different levels of disturbance, and to correlate their abundance and diversity of species, with that found in other arthropod communities of the same forests. The work was carried out in three municipalities in the North of the State of Mexico, where three types of different forests were identified by their degree of disturbance. These types include: 1) primary forest (PF), with typical species of a conserved forest; 2) mixed forest (MF), with species of a conserved forest and a reforestation effort; and 3) reforested forest (RF), with species used in reforestation efforts and indicative of disturbance. In each sample, an area of 2 500 m2 was selected. Each area had 16 pitfalls apiece and they were placed 10 m away from each other. Samples were collected twice; one from February through March 2009 (dry season) and another from August through September 2010 (rainy season), which produced a total of 192 traps. Obtained specimens were identified at the most taxonomically specific level. All data captured was transformed to √n + 0.5 and diversity index levels of Shannon and Simpson were calculated, as well as richness of species for ants, beetles, grasshoppers, true bugs, and spiders. The values of richness, diversity, and abundance were correlated with the Pearson coefficient, and to evaluate possible causal relationships between these, a path analysis was performed. Results suggested an important influence of the site over ant communities, and values of richness, abundance and diversity were correlated with the communities of spiders, beetles, grasshoppers and true bugs, but not for all the sites studied. Responses to environmental changes are not only on the numeric proportions of abundance, richness and diversity, but also in the indirect and casual ecological interactions. Finally, the data seems to indicate that the responses of the ants to the environmental changes are not necessarily reflected on other organisms’ communities, so the ants’ role as bioindicators can be limited. Rev. Biol. Trop. 64 (2): 571-585. Epub 2016 June 01.


ResumenPor sus características ecológicas las hormigas se han considerado útiles para la bioindicación. Sin embargo, entre los rasgos de un grupo bioindicador, debe haber una respuesta consistente y repetible a la perturbación. En este sentido, se han encontrado respuestas divergentes, incluso entre taxones estrechamente relacionados. El objetivo de este trabajo fue comparar la diversidad de las comunidades de hormigas en tres tipos de bosque templado con diferente nivel de perturbación y correlacionar su abundancia, riqueza de especies y la diversidad con aquella que se encuentra en otras comunidades de artrópodos en los mismos bosques. El trabajo se realizó en tres localidades del norte del Estado de México donde fueron identificados tres tipos de bosque diferenciados por grado de disturbio: 1) bosque primario (PF), con especies típicas de un bosque conservado; 2) bosque mixto (MF) con especies de bosque conservado y propias de reforestación y 3) bosque reforestado (RF) con especies utilizadas en reforestación e indicadoras de pertubación. En cada tipo de bosque se seleccionó un área de 2 500 m2 donde fueron colocadas 16 trampas de caída con una separación de 10 m. Fueron realizadas dos recolectas una de febrero a marzo 2009 (estación seca) y otra de agosto a septiembre 2010 (estación lluviosa), lo que dio un total de 192 trampas. Los especímenes obtenidos fueron identificados al nivel taxonómico más específico posible. Todos los datos de las capturas fueron transformados a √n+0.5 y fueron calculados los índices de diversidad de Shannon y Simpson y riqueza de especies tanto para hormigas como para escarabajos, chapulines, chiches y arañas. Los valores de riqueza, diversidad y abundancia fueron correlacionados con el coeficiente de Pearson y para evaluar posibles relaciones causales entre estos se realizó un análisis de sendero. Los resultados sugieren una influencia importante del sitio sobre las comunidades de hormigas y sus valores de riqueza, abundancia y diversidad están correlacionadas con las comunidades de arañas, escarabajos, chapulines y chinches, pero no para todos los sitios estudiados. Las respuestas a los cambios ambientales no sólo están en las proporciones numéricas de la abundancia, riqueza y diversidad sino también en las interacciones ecológicas indirectas y causales. Los resultados sugieren que las respuestas de las hormigas a los cambios ambientales no necesariamente se reflejan sobre comunidades de otros organismos por lo que su papel como bioindicadores puede ser limitado.


Subject(s)
Animals , Ants/classification , Biodiversity , Sentinel Species/classification , Ants/physiology , Temperature , Forests , Sentinel Species/physiology , Mexico
4.
Journal of Practical Radiology ; (12): 1061-1065, 2015.
Article in Chinese | WPRIM | ID: wpr-461318

ABSTRACT

Objective To explore the causal influences between activated regions in executive control network when participants were performing attention network test (ANT)under passive hyperthermia using Granger causality analysis.Methods Thirty male healthy participants which were randomly divided into control group (n=1 5)and experimental group (n=1 5)performed ANT task during two thermal conditions:hyperthermic condition (50℃)and normothermic condition (20℃)during functional magnetic reso-nance imaging.The data processing was performed using statistical parametric mapping 8 (SPM8).Granger causality analysis was performed on the resulted activated regions,as well as the correlations of the GC values with the reaction time in both groups.Results Between-group comparisons on Granger causality analysis revealed significantly enhanced influences of anterior cingulate gyrus and right inferior parietal lobule on dorsolateral prefrontal cortex,and bidirectional influences between dorsolateral prefrontal cortex and right superior parietal lobule,but decreased influence between right superior parietal lobule and right inferior parietal lobule.The correlation analysis showed significant correlation between GC value of right superior parietal lobule to dorsolateral prefrontal cortex and the reaction time in control group (r=-0.558,P =0.031),but yet there was no significant correlation in experimental group (r=0.355,P =0.257).Conclusion Heat stress affected the causal influences within the executive control network,which subse-quently disrupted the executive control performance during passive hyperthermia.

5.
International Journal of Biomedical Engineering ; (6): 261-265,后插1, 2013.
Article in Chinese | WPRIM | ID: wpr-573167

ABSTRACT

Objective To lateralize epileptic foci in interictal electroencephalography (EEG) signal by using causal analysis method.Methods On the basis of frequency domain causal analysis,the adapted directed transfer function (ADTF),power spectrum weighted ADTF(psADTF) method was proposed by applying the power spectrum information in defined frequency band with normalized ADTF,to fit the frequency information features of different epileptic wave.EEG signals of two groups of 30 epilepsy patients were analyzed by psADTF.Group Ⅰ included 15 presurgical patients and 104 epilepsy spikes were picked from EEG signals.Group Ⅱ included 15 outpatient patients and 98 epilepsy spikes were picked from EEG signals.Results 96 of 104 spikes of group Ⅰ were lateralized properly by psADTF according to surgery sites,and the accuracy rate was 92%.94 of 98 spikes of group Ⅱ were lateralized properly by psADTF according to three technicians' judgments,with the accuracy rate of 96%.Conclusion Our results proves that the psADTF method over interictal EEG spikes can be a great help to clinical epileptic foci lateralization.

6.
China Journal of Traditional Chinese Medicine and Pharmacy ; (12)2005.
Article in Chinese | WPRIM | ID: wpr-679975

ABSTRACT

Objective:To analyze the cause of the blood heat syndrome in psoriasis.Methods: Made the investigation form about information of psoriatic patients through DME method and reference both Chinese and foreign documents,analyzed main component of data by SAS software.Results: The first main component of blood heat syndrome in psoriasis are infection,drinking,dietetic problem,and emotion;the second main component is family history;the third main component is dampness;the forth main component is the allergy to the food;the fifth is outside irritation.Through the corresponding investigation we found that food include hot food,beef,sheep and sea food,emotion problem include over work and stress,dampness include work and living in humid place for long time,outside stimulus meant chemical stimulus.Conclusion: The main cause of the blood heat syndrome in psoriasis are infection,drinking,dietetic problem,and emotion,family history,humidity,allergy to the food and chemical stimulus in order.

7.
China Pharmacy ; (12)2001.
Article in Chinese | WPRIM | ID: wpr-530374

ABSTRACT

OBJECTIVE: To establish the theory and method for the analysis of systematic hypothesis on adverse drugs events. METHODS: System of causal analysis of adverse drug events and analytical methods on systematic hypothesis were established by applying systematical and scientific thoughts; and the application of which in the quality analysis of oral solid preparations and injections were explained. RESULTS: The system of causal analysis consists of subsystems of drug standard deficits, problems of drugs quality, adverse drugs reactions, medication errors and drug abuse subsystems. The analysis on systematic hypothesis consisted of 4 steps: producing signal, raising the hypothesis, demonstrating, and drawing the conclusions. CONCLUSION: The causal analysis system of adverse drug events and analytical methods on systematic hypothesis combined not only reductionism with holism but also analysis with synthesis, which can help to solve the complicated matter in clinical medication.

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