Association of Urinary and Blood Concentrations of Heavy Metals with Measures of Bone Mineral Density Loss: a Data Mining Approach with the Results from the National Health and Nutrition Examination Survey.

Osteoporosis and its consequence of fragility fracture represent a major public health problem. Human exposure to heavy metals has received considerable attention over the last decades. However, little is known about the influence of co-exposure to multiple heavy metals on bone density. The present study aimed to examine the association between exposure to metals and bone mineral density (BMD) loss. Blood and urine concentrations of 20 chemical elements were selected from 3 cycles (2005-2010) NHANES (National Health and Nutrition Examination Survey), in which we included white women over 50 years of age and previously selected for BMD testing (N = 1892). The bone loss group was defined as participants having T-score < - 1.0, and the normal group was defined as participants having T-score ≥ - 1.0. We developed classification models based on support vector machines capable of determining which factors could best predict BMD loss. The model which included the five-best features-selected from the random forest were age, body mass index, urinary concentration of arsenic (As), cadmium (Cd), and tungsten (W), which have achieved high scores for accuracy (92.18%), sensitivity (90.50%), and specificity (93.35%). These data demonstrate the importance of these factors and metals to the classification since they alone were capable of generating a classification model with a high prediction of accuracy without requiring the other variables. In summary, our findings provide insight into the important, yet overlooked impact that arsenic, cadmium, and tungsten have on overall bone health.

Recent applications of multivariate data analysis methods in the authentication of rice and the most analyzed parameters: A review.

Rice is one of the most important staple foods around the world. Authentication of rice is one of the most addressed concerns in the present literature, which includes recognition of its geographical origin and variety, certification of organic rice and many other issues. Good results have been achieved by multivariate data analysis and data mining techniques when combined with specific parameters for ascertaining authenticity and many other useful characteristics of rice, such as quality, yield and others. This paper brings a review of the recent research projects on discrimination and authentication of rice using multivariate data analysis and data mining techniques. We found that data obtained from image processing, molecular and atomic spectroscopy, elemental fingerprinting, genetic markers, molecular content and others are promising sources of information regarding geographical origin, variety and other aspects of rice, being widely used combined with multivariate data analysis techniques. Principal component analysis and linear discriminant analysis are the preferred methods, but several other data classification techniques such as support vector machines, artificial neural networks and others are also frequently present in some studies and show high performance for discrimination of rice.

Prediction of course completion by students of a university in Brazil / Predição de conclusão de curso por estudantes de uma universidade no Brasil / Predicción de conclusión de la carrera por estudiantes de una Universidad de Brasil

The conclusion of the undergraduate course by university students in the time predicted by the curriculum is desirable for young people and for society. The aim was to verify the reliability, sensitivity and specificity of a broad set of predictors for academic performance of university students, who completed the undergraduate course within the time predicted by the curricula, through data mining methodology, provided by the Support Vector Machines algorithm. A simple approach is proposed for the prediction of course completion by students in a university in Brazil. The dataset has 170 students who finished the course and 117 who did not finish. With the proposed methodology, it was possible to predict the course completion by students with an accuracy of 79.5% when using the 19 original variables. An accuracy of 75% was found using only 05 variables: Course, year of the course, gender, initial and final academic performance. (AU)

A conclusão do curso de graduação por estudantes universitários no tempo previsto pelo currículo é desejável para os jovens e para a sociedade. O objetivo foi verificar a confiabilidade, sensibilidade e especificidade de um amplo conjunto de indicadores sobre o desempenho acadêmico de estudantes universitários, que completaram o curso de graduação dentro do tempo previsto pelo currículo, por meio de metodologia de mineração de dados, fornecida pelo algoritmo Vector Machines Suporte. Uma abordagem simples é proposta para a previsão da conclusão do curso por estudantes de uma universidade no Brasil. O conjunto de dados tem 170 alunos que concluíram o curso e 117 que não terminaram. Com a metodologia proposta, foi possível prever a conclusão do curso pelos alunos com uma precisão de 79,5% quando se utiliza as 19 variáveis originais. Uma precisão de 75% foi encontrada usando apenas cinco variáveis: curso, ano do curso, o sexo, o desempenho inicial e final acadêmico. (AU)

La conclusión del curso de graduación de los estudiantes universitarios en el tiempo previsto por el plan de estudios es deseable para los jóvenes y para la sociedad. El objetivo fue verificar confianza, sensibilidad y especificidad de un amplio conjunto de indicadores sobre el desempeño académico de los estudiantes universitarios, que completaron el curso de graduación dentro del tiempo previsto por los planes de estudio, a través de la metodología de minería de datos, proporcionada por el algoritmo Vector Machines Suporte. Se propone un abordaje simple para previsión de la finalización de la carrera por estudiantes en una Universidad de Brasil. El conjunto de datos tiene 170 estudiantes que concluyeron la carrera y 117 que no terminaron. Con la metodología propuesta, fue posibe prever la finalización de la carrera por los estudiantes con una precisión de 79,5% cuando se utilizan las 19 variables originales. Una precisión de 75% fue encontrada usando apenas 5 variables: Curso, duración de la carrera, sexo, desempeño inicial y final académico. (AU)

Using Cluster Analysis and ICP-MS to Identify Groups of Ecstasy Tablets in Sao Paulo State, Brazil.

The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty-five elements were determined by ICP-MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K-means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave-one-out cross-validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.

The use of decision trees and naïve Bayes algorithms and trace element patterns for controlling the authenticity of free-range-pastured hens' eggs.

This article aims to evaluate 2 machine learning algorithms, decision trees and naïve Bayes (NB), for egg classification (free-range eggs compared with battery eggs). The database used for the study consisted of 15 chemical elements (As, Ba, Cd, Co, Cs, Cu, Fe, Mg, Mn, Mo, Pb, Se, Sr, V, and Zn) determined in 52 eggs samples (20 free-range and 32 battery eggs) by inductively coupled plasma mass spectrometry. Our results demonstrated that decision trees and NB associated with the mineral contents of eggs provide a high level of accuracy (above 80% and 90%, respectively) for classification between free-range and battery eggs and can be used as an alternative method for adulteration evaluation.