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1.
Rev. lasallista investig ; 19(1): 216-234, ene.-jun. 2022. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1423983

ABSTRACT

Resumen Introducción: la teoría del caos se usa para explicación de fenómenos complejos, cuya naturaleza no responde a comportamientos lineales y que a su vez no permite determinar con exactitud medidas y cálculos, pero que a pesar de ello se han logrado avances significativos en la ciencia, pudiéndose expandir además hasta las explicaciones de fenómenos sociales, siendo en este caso la violencia. Materiales y Métodos: se emplearon expresiones matemáticas para validar un modelo de realidad que describa aproximadamente índices de violencia a partir de datos reales. Resultados: se obtuvieron relaciones matemáticas que describen el comportamiento caótico, las cuales dependiendo de la tasa de violencia define si el valor tiende a cero, a un valor constante o un comportamiento caótico. Conclusiones: se obtuvo una relación matemática que describe el comportamiento entrópico de la violencia en sociedad, cuya tendencia caótica describe aproximadamente índices de violencia reales.


Abstract Introduction: chaos theory is used to explain complex phenomena, whose nature does not respond to linear behavior and which in turn does not allow exact measurements and calculations to be determined, but despite this, significant advances have been made in science, being able to also expand to the explanations of social phenomena, in this case being violence. Materials and Methods: mathematical expressions are used to validate the reality, which describes rates of violence from real data in Colombia. Results: mathematical relationships describing chaotic behavior were obtained, which, depending on the rate of violence, define whether the value tends to zero, a constant value or chaotic behavior. Conclusions: a mathematical relationship was obtained that describes the entropic behavior of violence in society, whose chaotic trend approximately describes real violence values.


Resumo Introdução: a teoria do caos é utilizada para explicar fenômenos complexos, cuja natureza não responde ao comportamento linear e que por sua vez não permite determinar medidas e cálculos exatos, mas apesar disso, avanços significativos foram feitos na ciência, expandindo para as explicações de fenômenos sociais, neste caso a violência. Materiais e Métodos: foram utilizadas expressões matemáticas para validar um modelo de realidade que descreve aproximadamente as taxas de violência a partir de dados reais. Resultados: foram obtidas relações matemáticas que descrevem o comportamento caótico, que, dependendo da taxa de violência, definem-se o valor que tende a zero, um valor constante ou um comportamento caótico. Conclusões: obteve-se uma relação matemática que descreve o comportamento entrópico da violência na sociedade, cuja tendência caótica descreve de forma aproximada os índices reais de violência.

2.
Rev. CES psicol ; 15(1): 1-23, ene.-abr. 2022. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1376227

ABSTRACT

Resumen El objetivo de este trabajo es aportar nuevas evidencias de calidad psicométrica para la adaptación argentina de la versión reducida del Cuestionario de Personalidad de Eysenck (EPQ-RS). Participaron 1136 personas de población general (52.5% femenino, edad media = 29.6 años, DE = 11.9) residentes en Buenos Aires, Argentina. La adaptación argentina se compone de 42 ítems con formato de respuesta dicotómica. Se realizó un análisis factorial confirmatorio a partir de la matriz de correlaciones tetracóricas. Esto permitió replicar la estructura propuesta por Eysenck para el modelo PEN (Psicoticismo-Extraversión-Neuroticismo) y la escala Sinceridad. Posteriormente, se ajustó el modelo logístico de dos parámetros por separado para los ítems de cada escala. Los ítems no mostraron funcionamiento diferencial según género. La discriminación de los ítems resultó moderada-alta. Los parámetros b se localizaron en rangos acotados de cada uno de los rasgos medidos, lo que originó que la precisión de las escalas varíe en el recorrido de los continuos. La escala Neuroticismo aporta más información en niveles medios del rasgo, Psicoticismo en los medio-bajos y Extraversión en los medio-altos. La escala Sinceridad mostró una función de información relativamente plana en todo el recorrido del rasgo. Se brindan evidencias de validez basadas en la relación con otras pruebas que miden facetas del neuroticismo y sintomatología. Las evidencias de validez y confiabilidad obtenidas ofrecen garantías de calidad suficientes para la aplicación de este instrumento en el contexto local y confirman la vigencia del modelo teórico que operacionaliza el EPQ-RS.


Abstract The aim of this work is to provide new evidence of psychometric quality for the Argentinean adaptation of the brief version of the Eysenck Personality Questionnaire (EPQ-RS). 1136 people from the general population (52.5% female, mean age = 29.6 years, SD = 11.9) residing in Buenos Aires, Argentina participated. The Argentinean adaptation consists of 42 items with dichotomous response format. A confirmatory factor analysis was performed from the tetrachoric correlation matrix. This allowed replicating the structure proposed by Eysenck for the PEN model (Psychoticism - Extroversion - Neuroticism) and the Lie scale. Subsequently, the two-parameter logistic model was adjusted separately for the items of each scale. The items did not show differential functioning by gender. Items discrimination was moderate-high. Parameters b were located in narrow ranges of each one of the measured traits, which caused the precision of the scales to vary along the trait continuums. The Neuroticism scale provides more information at medium levels of the trait, Psychoticism in the medium-low and Extraversion in the medium-high. The Lie scale showed a relatively flat information function throughout the trait. Evidence of validity based on the relationship with other tests that measure facets of neuroticism and symptomatology is provided. The evidence of validity and reliability obtained offers sufficient quality guarantees for the application of this instrument in the local context and confirms topicality of the theoretical model that operationalizes the EPQ-RS.

3.
Rev. bras. cir. cardiovasc ; 37(1): 1-6, Jan.-Feb. 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1365542

ABSTRACT

Abstract Introduction: Coronary artery bypass grafting (CABG) performed with and without cardiopulmonary bypass (CPB) support has been widely discussed in the literature. However, little is known about the outcomes of those techniques in Brazil. This study aims at exploring 30-day mortality and morbidity outcomes of on- and off-pump isolated CABG in a large sample from Southern Brazil. Methods: A single-center cohort with 1,767 patients undergoing isolated CABG (January 2013 - December 2018) was initially evaluated. Patients undergoing off-pump (N=397) and on-pump (N=1,370) CABG were identified. To obtain two completely homogeneous study groups, propensity score matching was used. The paired groups were compared by descriptive and univariate analyses. Then, logistic regression was used to verify the effects of on- and off-pump CABG on 30-day mortality. Results: None of the baseline characteristics showed significant difference between the groups (P>0.05). None of the analyzed morbidity outcomes showed any difference between the groups, including acute myocardial infarction (3.0% vs. 1.5%; P=0.192), stroke (2.4% vs. 4.2%; P=0.193), and major reoperation (0.6% vs. 0.3%; P=1.000), as well as the major adverse cardiovascular and cerebrovascular events composite outcome (6.3% vs. 7.5%; P=0.541). Mortality also did not differ (1.5% vs. 2.4%; P=0.401), and CPB support was not an independent predictor of risk for 30-day mortality (odds ratio: 2.052; 95% confidence interval: 0,609-6.913; P=0.246). Conclusion: After matching by propensity analyses, similar rates of on- and off-pump 30-day mortality and other major outcomes were observed. In addition, the use of CPB support was not an independent predictor of risk for the occurrence of 30-day mortality.

4.
International Journal of Surgery ; (12): 15-23,F3, 2022.
Article in Chinese | WPRIM | ID: wpr-929962

ABSTRACT

Objective:Based on Logistic regression and XGBoost algorithm, the prediction model of malignant brain edema (MBE) after vascular recanalization of anterior circulation acute great vessel occlusive stroke (ALVOS) was constructed, and the prediction performance was compared.Methods:A retrospective selection of 382 patients with anterior circulation ALVOS who underwent early endovascular treatment (EVT) in our hospital from March 2014 to June 2020 and successfully recanalized the occluded blood vessel was selected. The patients were divided into the training group ( n=267) and the test group ( n=115) according to the ratio of 7∶3 by the random number table method. According to whether the patients had MBE after successful recanalization of the occluded blood vessels, the training group was divided into the MBE group ( n=41) and non-MBE group ( n=226). The baseline data, treatment and brain computed tomography perfusion(CTP) results of MBE group and non-MBE group in training group and test group were compared respectively, including age, admission score of National Institutes of Health Stroke Scale (NIHSS), grade of cerebral collateral circulation, cerebral blood volume, and so on. Logistic regression model and XGBoost algorithm model were used to screen the predictors of MBE in ALVOS patients with occluded vessels successfully recanalized, and the discrimination and calibration of the two models were compared. The measurement data conforming to the normal distribution were expressed as mean ± standard deviation ( ± s), and the independent sample t test was used for comparison between the two groups. Non-normally distributed measurement data were represented by M ( Q1, Q3), using independent sample Mann-Whitney U test. The chi-square test was used to compare the count data between groups. Results:There was no significant difference in baseline data, treatment status, and cranial computed tomography perfusion (CTP) imaging results of the training group and the test group ( P>0.05). The age, admission systolic blood pressure, admission NIHSS score, proportion of hypertension, proportion of cerebral collateral circulation 0-2, proportion of thrombus removal times> 3 times, time from onset to recanalization, and cerebral blood volume (CBV) of MBE group were (68.95±8.04) years old, (146.71±22.73) mmHg, 17(13, 21) min, 87.80%, 82.93%, 68.29%, (365.64±87.83) min, (32.56±5.73) mL/100 g, obvious higher than the non-MBE group [(60.27±7.13) years old, (137.92±19.58) mmHg, 14(10, 18) points, 73.01%, 60.62%, 2.65%, (307.59±74.05) min, (27.49±5.46) mL/100 g] ( P<0.05). The results of Logistic regression model showed that age, NIHSS on admission, grade of cerebral collateral circulation, times of thrombectomy and time from onset to recanalization were the predictors of MBE after successful recanalization of occluded vessels after EVT in patients with anterior circulation ALVOS ( P<0.05). The top five important feature scores of XGBoost algorithm model were cerebral collateral circulation classification 34, embolectomy times 27, onset to vascular recanalization time 25, admission NIHSS score 22, age 16.In the training set, the area under the curve of the Logistic regression model was 0.816(95% CI: 0.749-0.883), and the Hosmer-Lemeshow test showed that χ2=1.547, P=0.438. The area under the curve of the XGBoost algorithm model was 0.856(95% CI: 0.799-0.913), and the Hosmer-Lemeshow test showed that χ2=1.021, P=0.998. Conclusion:Logistic regression model and XGBoost algorithm model had similar prediction performance for MBE after successful recanalization of occluded vessels after EVT in patients with anterior circulation ALVOS, and collateral circulation classification, number of thrombolysis, time from onset to recanalization, NIHSS score on admission, and age could be used as predictors.

5.
Braz. arch. biol. technol ; 65: e22210620, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364451

ABSTRACT

Abstract: Processes producing sigmoid curves are common in many areas such as biology, agrarian sciences, demography and engineering. Several mathematical functions have been proposed for modeling sigmoid curves. Some models such as the logistic, Gompertz, Richards and Weibull are widely used. This work introduces the Gudermannian function as an option for modeling sigmoid growth curves. The original function was transformed and the resulting equation was called the "Gudermannian growth model." This model was applied to four sets of experimental growth data to illustrate its practical application. The results were compared with those obtained by the logistic and Gompertz models. Since all these models are nonlinear in the parameters, the statistical properties of the least squares estimators were evaluated using measures of nonlinearity. For each experimental data set, the Akaike's corrected information criterion was utilized to discriminate among the models. In general, the Gudermannian model fitted better to the experimental data than the logistic and Gompertz models. The results showed that the Gudermannian model can be a good alternative to the classical sigmoid models.

6.
Rev. bras. estud. popul ; 39: e0182, 2022. tab
Article in Portuguese | LILACS | ID: biblio-1357049

ABSTRACT

A presente nota de pesquisa estima o impacto das mortes por Covid-19 sobre a esperança de vida no Brasil e regiões para os primeiros seis meses de 2020. Com base nos dados do Datasus e nas tábuas de vida com decremento simples, estimou-se que as mortes por Covid-19 ocorridas até 18 de agosto de 2020 tiveram impacto estatisticamente negativo na esperança de vida ao nascer, tanto masculina (-1,05 ano) quanto feminina (-0,85 ano). Em termos regionais, a maior perda em anos de vida é estimada no Norte (-1,65 ano para homens e -1,48 ano para mulheres), enquanto o Sul foi a região com menor impacto (-0,5 ano para homens e -0,36 para mulheres). Os resultados do modelo logístico para o país apontam que a mortalidade por Covid-19 tende a ser maior entre a população com mais de 65 anos, homens, pretos e de baixa instrução. As comorbidades aumentam a chance de desfecho morte, especialmente doença hepática e renal crônica. Tais análises foram ainda desagregadas por grandes regiões brasileiras.


This research note estimates the impact of deaths by Covid-19 on life expectancy in Brazil and the Regions for the first six months of 2020. Based on data from Datasus and the decreasing life tables, it was estimated that deaths by Covid-19 that occurred until August 18, 2020 had a statistically negative impact on life expectancy at birth, both male (-1.05 years) and female (-0.85 years). In regional terms, the greatest loss in years of life is estimated in the North (-1.65 years for men and -1.48 years for women), while in the South it was -0.5 year for men and -0.36 for women. The results of the logistic model for the country show that Covid-19 mortality tends to be higher among males, blacks, people with low education level and people over 65 years old. Comorbidities increase the chance of death, especially liver disease and chronic kidney disease. Such analyzes were further disaggregated by large Brazilian regions.


Esta nota de investigación estima el impacto de las muertes por Covid-19 en la esperanza de vida en Brasil y sus regiones durante los primeros seis meses de 2020. Con base en los datos de Datasus y de las tablas de vida decrecientes, se estimó que las muertes por Covid-19 que ocurrieron hasta el 18 de agosto de 2020 tuvieron un impacto estadísticamente negativo en la esperanza de vida al nacer, tanto en hombres (−1,05 años) como en mujeres (−0,85 año). En términos regionales, la mayor pérdida en años de vida se estima en el Norte (−1,65 año para los hombres y −1,48 años para las mujeres), mientras que en el Sur fue de −0,5 años para los hombres y −0,36 para las mujeres. Los resultados del modelo logístico para el país muestran que la mortalidad por Covid-19 tiende a ser mayor entre la población mayor de 65 años, hombres, afrobrasileros y de bajo nivel educativo. Las comorbilidades aumentan la probabilidad de muerte, especialmente la enfermedad hepática y la enfermedad renal crónica. Dichos análisis se desglosaron aun más por grandes regiones brasileñas.


Subject(s)
Humans , Socioeconomic Factors , Brazil , Mortality , Life Tables , COVID-19/mortality , Life Expectancy , Pandemics
7.
Asian Pacific Journal of Tropical Medicine ; (12): 356-363, 2021.
Article in Chinese | WPRIM | ID: wpr-951088

ABSTRACT

Objective: To identify the predictors of mortality among in-hospital melioidosis patients. Methods: A total of 453 patients in Hospital Sultanah Bahiyah, Kedah, and Hospital Tuanku Fauziah, Perlis with culture-confirmed melioidosis were retrospectively included in the study. Advanced multiple logistic regression was used to obtain the final model of predictors of mortality from melioidosis. The analysis was performed using STATA/SE 14.0. Results: A total of 50.11% (227/453) of the patients died at the hospital, and a majority (86.75%, 393/453) of cases were bacteremic. The logistic regression estimated that the bacteremic type of melioidosis, low platelet count, abnormal white blood cell counts, and increased urea value were predictors of mortality. The results showed that bacteremic melioidosis increased the risk of death by 4.39 times (OR 4.39, 95% CI 1.83-10.55, P=0.001) compared to non-bacteremic melioidosis. Based on laboratory test, the adjusted ORs from the final model showed that all three blood investigations were included as the associated factors of mortality for the disease [high white blood cell (>10×109/L): OR 2.43, 95% CI 1.41-4.17, P7 800 μmol/L): OR 5.53, 95% CI 2.50-12.30, P<0.001; and low level of urea (<2 500 μmol/L): OR 3.52, 95% CI 1.71-7.23, P=0.001). Conclusions: Routine blood investigations during a hospital admission can early identify predictors of mortality in melioidosis patients.

8.
Ciênc. rural (Online) ; 51(2): e20190990, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1142751

ABSTRACT

ABSTRACT: The objective of this study was to compare non-linear models fitted to the growth curves of quail to determine which model best describes their growth and check the similarity between models by analyzing parameter estimates.Weight and age data of meat-type European quail (Coturnix coturnix coturnix) of three lines were used, from an experiment in a 2 × 4 factorial arrangement in a completely randomized design, consisting of two metabolizable energy levels, four crude protein levels and six replicates. The non-linear Brody, Von Bertalanffy, Richards, Logistic and Gompertz models were used. To choose the best model, the Adjusted Coefficient of Determination, Convergence Rate, Residual Mean Square, Durbin-Watson Test, Akaike Information Criterion and Bayesian Information Criterion were applied as goodness-of-fit indicators. Cluster analysis was performed to check the similarity between models based on the mean parameter estimates. Among the studied models, Richards' was the most suitable to describe the growth curves. The Logistic and Richards models were considered similar in the analysis with no distinction of lines as well as in the analyses of Lines 1, 2 and 3.


RESUMO: Objetivou-se, neste estudo, comparar modelos não lineares ajustados às curvas de crescimento de codornas para determinar qual modelo que melhor descreve o crescimento de codornas e verificar a similaridade dos modelos analisando as estimativas dos parâmetros. Para as análises foram utilizados os dados peso e idade de codornas européias de corte (Coturnix coturnix coturnix) proveniente de três linhagens, em um esquema fatorial 2x4, instalado em um delineamento inteiramente casualizado, com dois níveis de energia metabolizável e quatro níveis de proteína bruta, com seis repetições. Os modelos não lineares utilizados foram: Brody, Von Bertalanffy, Richards, Logístico e Gompertz. Para a escolha do melhor modelo utilizou-se o Coeficiente de Determinação Ajustado, o Percentual de Convergência, o Quadrado Médio do Resíduo, o Teste de Durbin-Watson, o Critério de informação Akaike e o Critério de informação Bayesiano como avaliadores da qualidade do ajuste. Utilizou-se a análise de agrupamento para verificar, baseado nas estimativas médias dos parâmetros, a similaridades entre os modelos. Entre os modelos estudados, o Richard foi o mais adequado para descrever as curvas de crescimento. Os modelos Logístico e Richards foram considerados similares nas análises sem distinção de linhagem, bem como nas análises das Linhagem 1, 2 e 3.

9.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1778-1788, Sept.-Oct. 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1131564

ABSTRACT

Length growth as a function of time has a non-linear relationship, so nonlinear equations are recommended to represent this kind of curve. We used six nonlinear models to calculate the length gain of rainbow trout (Oncorhynchus mykiss) during the final grow-out phase of 98 days under three different feed types in triplicate groups. We fitted the von Bertalanffy, Gompertz, Logistic, Brody, Power Function, and Exponential equations to individual length-at-age data of 900 fish. Equations were fitted to the data based on the least square method using the Marquardt iterative algorithm. Accuracy of the fitted models was evaluated using a model performance metrics combining mean squared residuals (MSR), mean absolute error (MAE) and Akaike's Information Criterion corrected for small sample sizes (AICc). All models converged in all cases tested. Evaluation criteria for the Logistic model indicated the best overall fit (0.67 of combined metric MSR, MAE and AICc) under all different feeding types, followed by the Exponential model (0.185), and the von Bertalanffy and Brody model (0.074, respectively). Additionally, ∆AICc results identify the Logistic and Gompertz models as being substantially supported by the data in 100% of cases. The logistic model can be suggested for length growth prediction in aquaculture of rainbow trout.(AU)


O crescimento em comprimento em função do tempo tem uma relação não linear; por isso, funções não lineares são recomendáveis para descrever essa relação. Seis modelos não lineares foram usados para calcular o ganho em comprimento de truta-arco-íris (Oncorhynchus mykiss) durante 98 dias, na fase final da engorda, submetidas a três dietas diferentes em grupos triplicados. Foram ajustadas as equações de von Bertalanffy, Gompertz, logístico, Brody, função potencial e exponencial a dados individuais de comprimento-idade de 900 peixes. O ajuste foi feito pelo método dos mínimos quadrados, usando-se o algoritmo iterativo de Marquardt. A precisão do ajuste foi avaliada pelo uso de critérios combinados de ajuste: quadrado médio do resíduo (QMR), erro médio absoluto (EMA) e o critério de informação de Akaike corrigido para tamanhos amostrais pequenos (AICc). Todos os modelos atingiram a convergência para cada caso avaliado. Os critérios de avaliação do modelo logístico indicaram o melhor ajuste geral (0,67 vez dos critérios combinados MSR, MAE e AICc) para cada grupo de peixe avaliado, seguido pelo modelo exponencial (0,185) e os modelos von Bertalanffy e Brody, com 0,074, respectivamente. Similarmente, os resultados de ΔAICc identificaram-se ao modelo logístico e ao de Gompertz, com grande suporte das informações em 100% dos casos. Por fim, o modelo logístico pode ser sugerido na predição do crescimento em comprimento de truta-arco-íris cultivada.(AU)


Subject(s)
Animals , Oncorhynchus mykiss/growth & development , Nonlinear Dynamics , Aquaculture/methods , Logistic Models
10.
Ciênc. rural (Online) ; 50(3): e20190408, 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1089551

ABSTRACT

ABSTRACT: Assessing sugarcane (Saccharum spp.) stalk growth helps to adequately manage the phenological stages of the crop. The aim of this study was to describe the height-growth curve of four sugarcane varieties (RB92579, RB93509, RB931530 and SP79-1011), in irrigated plant-cane and ratoon cane plantations, using the Logistic and Gompertz nonlinear models, while considering all deviations from assumptions. The model parameters were estimated based on the least squares method using the Gauss-Newton algorithm. To select the most suitable model, nonlinear measures, adjusted coefficient of determination (R2 adj), residual standard deviation (RSD), and corrected Akaike information criterion (AICc) were used. Based on the best models, stalk height growth rates and crop phenological stages were determined using critical points. All tests were performed in the free software environment for statistical computing and graphics, R. In general, the Logistic and Gompertz models without AR(1) better described the plant-cane and ratoon cane stalk height, respectively. All varieties showed early growth, and the RB92579 variety presented higher rates in both cycles.


RESUMO: A avaliação do crescimento dos colmos de cana-de-açúcar (Saccharum spp.) ajuda a adequar o manejo com as fases fenológicas da cultura. Objetivou-se com este trabalho descrever a curva de crescimento da altura de quatro variedades de cana-de-açúcar (RB92579, RB93509, RB931530 e SP79-1011), nos cultivos de cana planta e cana soca irrigados, utilizando os modelos não lineares Logístico e Gompertz, e considerando eventuais desvios de pressupostos. A estimação dos parâmetros dos modelos foi feita com base no método dos mínimos quadrados utilizando o Algoritmo de Gauss-Newton. Para selecionar o modelo mais adequado foram utilizadas as medidas de não linearidade, o coeficiente de determinação ajustado (R2 aj), o desvio padrão residual (DPR) e o critério de informação de Akaike corrigido (AICc). Com base nos melhores modelos foram determinadas as taxas de crescimento da altura dos colmos e as fases fenológicas da cultura por meio dos pontos críticos. Todas as análises foram realizadas no software estatístico R. No geral, os modelos Logístico e Gompertz sem AR(1) descreveram melhor a altura dos colmos em cana planta e cana soca, respectivamente. Todas as variedades apresentaram crescimento precoce, a variedade RB92579 apresentou maiores taxas em ambos os ciclos.

11.
Chinese Pharmaceutical Journal ; (24): 1099-1103, 2019.
Article in Chinese | WPRIM | ID: wpr-857977

ABSTRACT

OBJECTIVE: To study the algorithm of four-parameter logistic regression and apply the model in the potency calibration of bacterial endotoxin standard. METHODS: The potency of endotoxin reference standard was estimated by a novel monocyte activation test,HL60-IL6 assay.The endotoxin national standard was set as standard, while the endotoxin working standard was set as test. The four-parameter logistic model was fitted by the method of nonlinear least squares when observations of standard or sample solutions were plotted against endotoxin concentration. The algorithm was performed by C Language, the RESULTS: of which were compared by those of softmax, R Language as well as Microsoft Office Excel. RESULTS The estimated parameters as well as estimated potency were parallel between the four statistical tools. The goodness-of-fit were all over 0.99.The variance was within 0.1%. CONCLUSION: The four-parameter logistic model can be established by the four statistical tools. Researchers can select a suitable tool according to demands.

12.
Acta bioquím. clín. latinoam ; 52(3): 339-345, set. 2018. graf, tab
Article in Spanish | LILACS | ID: biblio-973458

ABSTRACT

La determinación del nivel de anticuerpos por medio de ensayos ELISA exige construir una curva de calibración según el modelo logístico de 4 parámetros (4PL); no obstante, es común que el bioquímico realice estimaciones y ajuste los datos de calibración con modelos alternativos. Se buscó determinar para un ensayo ELISA semicuantitativo el modelo que mejor ajusta los datos de calibración y cuál de los modelos alternativos explorados genera menor error relativo porcentual (ERP) al predecir las concentraciones de los calibradores. Para esto se empleó un ELISA indirecto y se ajustaron las densidades ópticas (DO) de los calibradores según los modelos i) exponencial ii) Boltzmann iii) Boltzmann semi log iv) Deming v) regresión lineal vi) 4PL vii) cuadrático. Se encontró que el mejor ajuste lo proveen los modelos v) (R2=0,9914), i) (R2=0,9652) y iii) (R2=0,9650). Sin embargo, los modelos i) y iii) tienen mejor desempeño en el procedimiento de ajuste inverso: el ERP se mantuvo ≤20% en el rango cubierto por los 6 calibradores (0-100 UI/mL). Los modelos lineales iv) y v) presentaron ERP elevados en el rango testeado. En resumen, el ajuste exponencial i) y el ajuste de Boltzmann iii), combinan valores de R2 y ERP comparables al modelo 4PL, por lo cual es inapropiado cualquier tipo de ajuste lineal.


Determination of the levels of specific antibodies by semiquantitative ELISAs requires the construction of a 4 parameter logistic regression (4PL) calibration curve. However, alternative models are often employed to adjust and estimate calibration data. The aims of this work were to determine the model that best adjusts calibration data, and which alternative model generates a lower relative percentage error (RPE) in the prediction of calibrator concentrations. An IgA anti-gliadin ELISA was used. The optical density values (OD) of calibrators were adjusted with the following mathematical models: i) Exponential, ii) Boltzmann, iii) Boltzmann semilog, iv) Deming, v) Linear regression, vi) 4PL, and vii) Quadratic. Results indicated that the best adjustment is given by models v) (R2=0.9914), i) (R2=0.9652) and iii) (R2=0.9650). However, models i) and iii) performed better in the reciprocal adjustment procedure: RPE values were ≤20% for all the calibrator levels analyzed (0-100 IU/mL). The linear models iv) and v) had high RPE values. To sum up, the exponential (i) and Boltzmann (iii) adjustments present R2 and RPE values similar to those of the 4PL, the use of any linear adjustment being inappropriate.


A determinação do nível de anticorpos por meio de ELISA requer a construção de uma curva de calibração de acordo com o modelo logístico de 4 parâmetros (4PL); no entanto, é comum o bioquímico fazer estimativas e ajustar os dados de calibração com modelos alternativos. Procurou-se determinar para um ensaio ELISA de modelo semiquantitativo o modelo que melhor se ajusta os dados de calibração e qual dos modelos alternativos explorados gera menor erro relativo percentual (ERP) ao prever as concentrações dos calibradores. Para isso, um ELISA indireto foi utilizado e se ajustaram as densidades ópticas (DO) dos calibradores segundo os modelos i) exponencial ii) Boltzmann iii) Boltzmann semi log iv) Deming v) regressão lineal iv) 4PL vii) quadrático. Verificou-se que o melhor ajuste é fornecido pelos modelos v) (R2= 0,9914), vi) (R2= 0,9652) e iii) (R2= 0,9650). No entanto, os modelos i) e iii) têm melhor desempenho no procedimento de ajuste inverso: o ERP permaneceu ≤20% na faixa coberta pelos 6 calibradores (0-100 UI/mL). Os modelos lineares iv) e v) apresentaram alto ERP na faixa testada. Em resumo, o ajuste exponencial i) e o ajuste de Boltzmann iii) combinam valores de R2 e ERP comparáveis ao modelo de 4PL, sendo inadequado qualquer tipo de ajuste linear.


Subject(s)
Calibration , Enzyme-Linked Immunosorbent Assay , Immunoassay , Methods , Immunoglobulin A , Linear Models , Logistic Models , Efficiency , Allergy and Immunology , Reference Standards , Gliadin , Antibodies
13.
Chinese Journal of Geriatrics ; (12): 984-987, 2018.
Article in Chinese | WPRIM | ID: wpr-709400

ABSTRACT

Objective To investigate the practical value of a logistic regression model of serum indexes in distinguishing between geriatric depression and geriatric depressive state. Methods A total of 160 patients were recruited from the outpatient department from January 2013 to January 2016 ,and were divided into a depression group (n= 80)and a depressive state group (n= 80) ,with retrospective diagnoses based on the Chinese Classification of Mental Disorders-Third-Edition(CCMD-3).Serum samples were collected and enzyme linked immunosorbent assays (ELISA)were used to determine the concentrations of brain-derived neurotrophic factor (BDNF ) ,glial cell line-derived neurotrophic factor(GDNF) ,fibroblast growth factor 2(FGF-2) ,vascular endothelial growth factor (VEGF) ,interleukin-1β(IL-1β) ,interleukin-6 (IL-6) ,interleukin-10 (IL-10) ,tumor necrosis factor-α(TNF-α) ,cortisol (CORT ) ,and platelet-derived growth factor (PDGF).Binary logistic regression analysis was used to establish the regression model ,and the ROC curve was drawn to explore its value of differentiating geriatric depression from depressive state. Results The levels of serum BDNF , GDNF and VEGF in the depression group were lower than those in the depressive state group (BDNF :208.7 ± 41.4 vs.262.9 ± 84.6 ng/L ,GDNF :92.3 ± 18.6 vs. 101.4 ± 30.9 ng/L ,VEGF :223.1 ± 98.2 vs. 257.8 ± 77.2ng/L) ,while the levels of IL-1βand CORT in the depression group were higher than in the depressive group(IL-1β:27.0 ± 4.9 vs.19.6 ± 5.7 μg/L ,CORT :96.3 ± 16.7 vs.83.0 ± 17.3 nng/L).In multivariate logistic regression analysis ,BDNF(OR = 0.987 ,P = 0.001) ,IL-1β(OR =1.29 ,P = 0.000)and CORT (OR = 1.065 ,P = 0.000)were selected to build the regression model. The regression equation was P=1/[1+e-(- 8.546 - 0.013(BDNF)+ 0.258(IL -1β)+ 0.063(CORT)) ]and the area under the ROC curve was 0.966.Compared with retrospective diagnoses made two weeks later ,the correct diagnosis rate of the logistic model was 90.47%. Conclusions The Logistic regression model of serum indexes can further differentiate between geriatric depression and depressive state which also offers additional benefits for the diagnosis ,differential diagnosis ,and treatment of depression.

14.
CoDAS ; 30(4): e20170071, 2018. tab, graf
Article in English | LILACS | ID: biblio-890844

ABSTRACT

ABSTRACT Purpose : This study was conducted to identify variables associated with mouth breathing diagnosis in children, based on multidisciplinary domains. Methods 119 children, six to 12 years old, underwent anamnesis, speech therapy (orofacial structures and stomatognathic functions), otorhinolaryngologic (OTRL) with clinical and endoscopic examinations, dental (occlusion) and physiotherapy (body posture and nasal patency) assessments. Nasal patency was evaluated using Peak Nasal Inspiratory Flow (PNIF) and the Nasal Obstruction Symptom Evaluation (NOSE) scale. A multiple logistic regression was performed considering breathing mode as the dependent variable and the co-variables from each multidisciplinary assessment as associated variables. Results Association with MB diagnosis was found in each professional domain with: nasal obstruction report (Odds ratio - OR=5.55), time of pacifier use (OR=1.25), convex facial type (OR=3.78), obtuse nasal angle (OR=4.30), half-open or open lip posture (OR=4.13), tongue position on the mouth floor (OR=5.88), reduced hard palate width (OR=2.99), unexpected contraction during mastication (OR=2.97), obstructive pharyngeal tonsils (OR=8.37), Angle Class II malocclusion (OR=10.85) and regular gingival maintenance (OR=2.89). Conclusion We concluded that a multidisciplinary diagnosis is important, given that each evaluation domain, including OTRL, dental and speech therapy, presented variables associated with MB diagnosis. Body posture and nasal patency variables were not associated with MB.


RESUMO Objetivo Este estudo foi conduzido para identificar as variáveis associadas ao diagnóstico de respiração oral em crianças, baseado nos domínios multidisciplinares. Método Cento e dezenove crianças, de seis a 12 anos, realizaram uma avaliação abrangente composta por uma anamnese e exames fonoaudiológico (estruturas orofaciais e funções estomatognáticas), otorrinolaringológico (avaliação clínica e endoscópica), odontológico (conservação oral e oclusão) e fisioterapêutico (postura corporal e permeabilidade nasal). A permeabilidade nasal foi aferida utilizando-se o Pico de Fluxo Inspiratório Nasal (PFIN) e a escala NOSE (Nasal Obstruction Symptom Evaluation). Foi realizada uma regressão logística múltipla, considerando o modo respiratório como variável dependente e as covariáveis de cada avaliação multidisciplinar como variáveis associadas. Resultados Foi encontrada uma associação do diagnóstico de respiração oral com variáveis de cada domínio profissional: relato de obstrução nasal (Odds ratio - OR=5,55), tempo de uso de chupeta (OR=1,25), tipo facial convexo (OR=3,78), ângulo nasolabial obtuso (OR=4,30), postura de lábios entreabertos e abertos (OR=4,13), postura de língua no assoalho oral (OR=5,88), largura do palato duro reduzida (OR=2,99), contrações inesperadas durante a mastigação (OR=2,97), tonsilas faríngeas obstrutivas (OR=8,37), má oclusão classe II de Angle (OR=10,85) e estado gengival regular (OR=2,89). Conclusão Concluiu-se que o diagnóstico multidisciplinar é importante, uma vez que as avaliações dos domínios fonoaudiológico, otorrinolaringológico e odontológico obtiveram variáveis associadas ao diagnóstico de respiração oral. As variáveis relacionadas à postura corporal e permeabilidade nasal não foram associadas ao diagnóstico de respiração oral.


Subject(s)
Humans , Male , Female , Child , Mouth Breathing/diagnosis , Nasal Obstruction/complications , Nasal Obstruction/diagnosis , Rhinitis , Anthropometry , Cross-Sectional Studies , Regression Analysis , Mouth Breathing/etiology , Mouth Breathing/physiopathology
15.
Ciênc. rural (Online) ; 48(1): e20161097, 2018. tab, graf
Article in English | LILACS | ID: biblio-1044972

ABSTRACT

ABSTRACT: The goal of this study was to elucidate the growth and development of the Asian pear fruit, on the grounds of length, diameter and fresh weight determined over time, using the non-linear Gompertz and Logistic models. The specifications of the models were assessed utilizing the R statistical software, via the least squares method and iterative Gauss-Newton process (DRAPER & SMITH, 2014). The residual standard deviation, adjusted coefficient of determination and the Akaike information criterion were used to compare the models. The residual correlations, observed in the data for length and diameter, were modeled using the second-order regression process to render the residuals independent. The logistic model was highly suitable in demonstrating the data, revealing the Asian pear fruit growth to be sigmoid in shape, showing remarkable development for three variables. It showed an average of up to 125 days for length and diameter and 140 days for fresh fruit weight, with values of 72mm length, 80mm diameter and 224g heavy fat.


RESUMO: Este trabalho teve por objetivo descrever o crescimento e desenvolvimento de frutos de pereira asiática, com base no comprimento, diâmetro e peso fresco obtidos ao longo do tempo, pelos modelos não lineares Gompertz e Logístico. Os parâmetros dos modelos foram estimados utilizando rotinas no software R, pelo método de mínimos quadrados e processo iterativo de Gauss-Newton (DRAPER & SMITH, 2014). Os modelos foram comparados utilizando o desvio padrão residual, coeficiente de determinação ajustado e o critério de informação de Akaike. A correlação residual presente nos dados de comprimento e diâmetro foi modelada por processo auto-regressivo de segunda ordem, tornando os resíduos independentes. O modelo Logístico mostrou-se mais adequado para descrever os dados, comprovando o caráter sigmoidal do crescimento da pera asiática com desenvolvimento acentuado das três variáveis, com até 125 dias para o comprimento e diâmetro e 140 dias para o peso fresco dos frutos, estabilizando-se, em média, com 72mm de comprimento, 80mm de diâmetro e 224g de peso fresco.

16.
rev. udca actual. divulg. cient ; 20(2): 363-374, jul.-dic. 2017. ilus
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1094685

ABSTRACT

El tomate (Solanum lycopersicum L.) es una de las hortalizas más consumidas en el mundo y es atacada por numerosas enfermedades, entre las cuales, está la marchitez vascular, causada por Fusarium oxysporum f. sp. lycopersici. El patógeno, por ser habitante del suelo, es difícil de manejar. Una vez el suelo se infesta puede permanecer con el patógeno por tiempo indefinido. Debido al cultivo sucesivo de tomate en el mismo lugar, la población del hongo aumenta y, por ende, la incidencia de la enfermedad. Aún no se han establecido umbrales de daño económico ni sistemas de predicción, pero se conocen algunas condiciones del suelo, que pueden disminuir la incidencia de la enfermedad, como pH alto o una población alta de microorganismos antagonistas. Se han reportado numerosas prácticas de manejo enfocadas, especialmente hacia el suelo; sin embargo, son pocos los reportes acerca del manejo integrado de la enfermedad. Para la preparación de este documento, se revisó la literatura mundial y se analizó la naturaleza del patógeno, su ciclo de vida y diseminación, conocimiento primordial para realizar un manejo adecuado de la enfermedad; también las diferentes prácticas de manejo y, finalmente, la combinación de estas prácticas. El objetivo de esta revisión fue reunir la información más relevante generada en los últimos años, en torno al manejo integrado de F. oxysporum f. sp. lycopersici, enfocando cada práctica dentro del modelo logístico de Van der Plank, que permite darles una interpretación cuantitativa.


Tomato (Solanum lycopersicum L.) is one of the most consumed vegetables in the world and is attacked by numerous diseases, including the vascular wilt, caused by Fusarium oxysporum f. sp. lycopersici. The pathogen, being an inhabitant of the soil is difficult to manage. Once the soil is infested, it can remain with the pathogen indefinitely. Due to the successive cultivation of tomato in the same field the population of the fungus increases and, consequently, the incidence of the disease. No thresholds for economic damage or prediction systems have yet been established, but some soil conditions are known to reduce the incidence of the disease, such as high pH or a high population of antagonistic microorganisms. Numerous management practices have been reported, especially focused toward the soil; however, there are few articles on integrated management of the disease. For the preparation of this document, the world literature was reviewed and addressed the nature of the pathogen, its life cycle and dissemination, essentials to carry out an adequate management of the disease; also, the different management practices and finally the combination of these practices. The objective of this review was to gather the most relevant information generated in recent years on the integrated management of F. oxysporum f. sp. lycopersici, focusing each practice within the logistic model of Van der Plank, which allows giving to each one a quantitative interpretation.

17.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1537024

ABSTRACT

La siembra del cultivo de moringa con semillas gámicas tiene ventajas sobre la propagación vegetativa con estacas, por la buena disponibilidad de semillas, rapidez en la fase de semillero, facilidad de trasplante, economía en las labores y mejor anclaje definitivo; sin embargo, se ha reportado que las semillas maduras presentan bajo porcentaje de germinación, por lo cual, se hizo una investigación en la Universidad de Córdoba, Colombia, con el objetivo de establecer el efecto de la imbibición de semillas en agua sobre el porcentaje de germinación. Se hizo un bioensayo con semillas extraídas de un árbol de un año de edad, sembrado en el campo experimental de cultivos de hortalizas. El diseño experimental utilizado fue completamente al azar y se aplicaron tres tratamientos: semillas embebidas en agua 24h, semillas embebidas en agua 48h y semillas embebidas en agua 72h, teniendo como testigo semillas sin imbibición en agua. Los datos de porcentaje de germinación PG se ajustaron al modelo logístico y se obtuvieron la velocidad absoluta de germinación VAG y velocidad relativa de germinación VRG. De acuerdo con los resultados, se estableció que, a mayor tiempo de imbibición de las semillas, se disminuyó el porcentaje de germinación, desde 66 hasta 29% y la velocidad absoluta de germinación, desde 29 semillas∙día-1 hasta 7 semillas∙día-1.


Sowing of the moringa crop with gamic seeds has advantages over vegetative propagation with stakes due to the good availability of seeds, rapidity in the nursery phase, ease of transplantation, economy in the work and best definitive anchorage. However, it has been reported that mature seeds have a low percentage of germination, therefore a research was made at the Universidad de Córdoba, Colombia, with the objective of establishing the effect of the imbibition of seeds in water on germination percentage. A bioassay with seeds extracted from a one year old tree, planted in the experimental field of vegetable crops was carried out. The experimental design used was completely randomized and three treatments were applied, seed imbibition in water during 24h, seed imbibition in water during 48h and seed imbibition in water during 72h having as control seeds without imbibition in water. The germination percentage GP data were adjusted to the logistic model and the absolute rate of germination ARG and relative rate of germination RRG were obtained. According to the results it was established that the GP decreased at a longer seed imbibition time and AGR decreased from 29 seeds∙day-1 to 7 seeds∙day-1.

18.
Chinese Journal of Epidemiology ; (12): 1073-1077, 2017.
Article in Chinese | WPRIM | ID: wpr-737777

ABSTRACT

Objective To analyze the influencing factors on condom use among 35-yearsor-older female sex workers (OFSWs) in Qingdao by using the three-level logistic model.Methods From March to June 2014,OFSWs were recruited in Qingdao,using respondent-driven sampling.Related information on OFSWs and their recent five sexual partners (not including husband) were obtained by conducting a questionnaire survey on OFSWs.A Three-level logistic regression model was conducted to analyze the influencing factors of condom use between OFSWs and their sexual partners.Results A total of 420 OFSWs participated the survey as well as information on 2 100 sexual partners.Results from the empty model showed that the use of condoms among OFSWs having an aggregation that related to the levels of working sites and their own behaviors.Results from the three-levels of logistic model analysis showed that,OFSWs that having had junior middle school education (OR=1.450,95%CI:1.054-1.994)/high school education or above (OR=2.264,95% CI:1.215-4.222),knowing the function of condom use (OR=2.004,95% CI:1.273-3.154) would have higher rates of condom use.OFSWs with higher score of attitude on condom use (OR=0.796,95%CI:0.745-0.849),having had syphilis infections in the past (OR=0.657,95% CI:0.478-0.902) would have lower rate of condom use.For the sexual partners,the rate of condom use among OFSWs' regular partners were higher than that of OFSWs' boyfriends (OR=15.291,95%CI:8.441-27.700;OR=29.032,95% CI:15.413-54.682).Conclusion Condom use of OFSWs was affected by behaviors of both OFSWs themselves and their sexual partners.Prevention and control programs should focus on OFSWs and their sexual partners at the same time.The key intervention contents should include target populations as:OFSWs with low level of education,having had infections of syphilis,those who do not use condoms with their trusted partners.

19.
Chongqing Medicine ; (36): 3073-3076, 2017.
Article in Chinese | WPRIM | ID: wpr-608816

ABSTRACT

Objective To study the diagnostic value of combined detection of serum CEA,CA199,CA125,AFP and fecal occult blood(FOB) in Dukes B stage colon carcinoma.Methods The above indicators in 56 patients with colon carcinoma (colon carcinoma group),35 patients with colonic polyp benign disease and 41 healthy individuals undergoing physical examination were measured.Then the sensitivity,and specificity of single index detection and their combined detection were analyzed.Results The levels and positive rates of CEA,CA199,CA125 and FOB in the colon cancer group were significantly higher than those in the colonic polyp group and healthy control group (P<0.05),but the AFP level and positive rate had no statistical difference compared with the colonic polyp group.Serum CEA,CA125,CA199 and FOB were selected into the Logistic regression equation.The corresponding areas under the curve (AUC) were 0.745,0.886,0.792 and 0.864 respectively;the positive detection rates were 48.2 %,35.7 %,39.3 % and 78.6 % respectively.The combined detection could increased the specificity,sensitivity and AUC to 87.5 %,92.1% and 0.957,which were more superior to that in the single index detection.Conclusion The combined detection of serum CEA,CA199,CA 125 and FOB can provide the powerful basis for early diagnosing colonic cancer.

20.
Chinese Journal of Epidemiology ; (12): 1073-1077, 2017.
Article in Chinese | WPRIM | ID: wpr-736309

ABSTRACT

Objective To analyze the influencing factors on condom use among 35-yearsor-older female sex workers (OFSWs) in Qingdao by using the three-level logistic model.Methods From March to June 2014,OFSWs were recruited in Qingdao,using respondent-driven sampling.Related information on OFSWs and their recent five sexual partners (not including husband) were obtained by conducting a questionnaire survey on OFSWs.A Three-level logistic regression model was conducted to analyze the influencing factors of condom use between OFSWs and their sexual partners.Results A total of 420 OFSWs participated the survey as well as information on 2 100 sexual partners.Results from the empty model showed that the use of condoms among OFSWs having an aggregation that related to the levels of working sites and their own behaviors.Results from the three-levels of logistic model analysis showed that,OFSWs that having had junior middle school education (OR=1.450,95%CI:1.054-1.994)/high school education or above (OR=2.264,95% CI:1.215-4.222),knowing the function of condom use (OR=2.004,95% CI:1.273-3.154) would have higher rates of condom use.OFSWs with higher score of attitude on condom use (OR=0.796,95%CI:0.745-0.849),having had syphilis infections in the past (OR=0.657,95% CI:0.478-0.902) would have lower rate of condom use.For the sexual partners,the rate of condom use among OFSWs' regular partners were higher than that of OFSWs' boyfriends (OR=15.291,95%CI:8.441-27.700;OR=29.032,95% CI:15.413-54.682).Conclusion Condom use of OFSWs was affected by behaviors of both OFSWs themselves and their sexual partners.Prevention and control programs should focus on OFSWs and their sexual partners at the same time.The key intervention contents should include target populations as:OFSWs with low level of education,having had infections of syphilis,those who do not use condoms with their trusted partners.

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