The application of adaptive partitioned random search in feature selection problem

Feature selection is one of important and frequently used techniques in data preprocessing. It can improve the efficiency and the effectiveness of data mining by reducing the dimensions of feature space and removing the irrelevant and redundant information. Feature selection can be viewed as a global optimization problem of finding a minimum set of M relevant features that describes the dataset as well as the original N attributes. In this paper, we apply the adaptive partitioned random search strategy into our feature selection algorithm. Under this search strategy, the partition structure and evaluation function is proposed for feature selection problem. This algorithm ensures the global optimal solution in theory and avoids complete randomness in search direction. The good property of our algorithm is shown through the theoretical analysis.

Detection of Spinal Muscular Atrophy Carriers in a Sample of the Brazilian Population

Background: Spinal muscular atrophy is a common autosomal recessive neuromuscular disorder caused by mutations in the SMN1 gene. Identification of spinal muscular atrophy carriers has important implications for individuals with a family history of the disorder and for genetic counseling. The aim of this study was to determine the frequency of carriers in a sample of the nonconsanguineous Brazilian population by denaturing high-performance liquid chromatography (DHPLC). Methods: To validate the method, we initially determined the relative quantification of DHPLC in 28 affected patients (DHPLC values: 0.00) and 65 parents (DHPLC values: 0.49-0.69). Following quantification, we studied 150 unrelated nonconsanguineous healthy individuals from the general population. Results: Four of the 150 healthy individuals tested (with no family history of a neuromuscular disorder) presented a DHPLC value in the range of heterozygous carriers (0.6-0.68). Conclusions: Based on these results, we estimated there is a carrier frequency of 2.7% in the nonconsanguineous Brazilian population, which is very similar to other areas of the world where consanguineous marriage is not common. This should be considered in the process of genetic counseling and risk calculations. Copyright (C) 2011 S. Karger AG, Basel

Nocturnal awakening with headache and its relationship with sleep disorders in a population-based sample of adult inhabitants of Sao Paulo City, Brazil

Our aim was to estimate the prevalence of nocturnal awakening with headache (NAH) in the population of Sao Paulo City according to gender, age (20-80 years old) and socioeconomic classes and its relationship to sleep disorders, sleep parameters, anxiety, depression, fatigue, life quality and obesity. We used a population-based survey with a representative three-stage cluster sample. Questionnaires and scales were applied face-to-face, and polysomnography was performed in 1101 volunteers, aged 42 +/- 14 years, 55% women. The complaint of NAH occurring at least once a week had a prevalence of 8.4%, mostly in women, obese subjects and those aged 50-59 years-old. We observed associations of NAH with insomnia, restless leg syndrome (RLS), nightmares and bruxism, but not obstructive sleep apnea syndrome. In a logistics regression model, risk factors for NAH were female gender, odds ratio (OR) (95% confidence interval [CI]) 4.5 (2.8-7.3); obesity, OR 1.9 (1.1-3.3); age between 50 and 59 years, OR 2.4 (1.2-4.7); severe anxiety, OR 8.1 (3.6-18.1); RLS, 2.7 (1.2-5.6); and nightmares, 2.2 (1.3-3.7). Our study shows that NAH was highly prevalent in the population of Sao Paulo and suggests that this phenomenon has specific characteristics with specific risk factors: obesity, RLS and nightmares.

Study of the Discriminative Validity of the PHQ-9 and PHQ-2 in a Sample of Brazilian Women in the Context of Primary Health Care

PURPOSE. This study aimed to assess the discriminative validity of the Brazilian version of the Patient Health Questionnaire (PHQ-9) and of its reduced version (PHQ-2). DESIGN AND METHODS. The sample consisted of 177 women (60 cases of depression and 117 noncases). The SCID-IV was used as the gold standard. FINDINGS. For the PHQ-9, a cutoff score equal to or higher than 10 proved to be the most adequate for the screening of depression, whereas the best cutoff score for the PHQ-2 was found to lie between 3 and 4. PRACTICE IMPLICATIONS. The systematic use of these instruments in nursing and in the context of primary health care could favor the early detection of depression.

Expanded protocol of orofacial myofunctional evaluation with scores: Validity and reliability

Objective: Clinical evaluation of the stomatognathic system is indispensable for the diagnosis of orofacial myofunctional disorders. In order to obtain a more precise diagnosis, the protocol of orofacial myofunctional evaluation with scores (OMES protocol) (Int. J. Pediatr. Otorhinolaryngol. 72 (2008) 367-375) was expanded in terms of number of items and scale amplitude. The proposal of this study is to describe the expanded OMES protocol (OMES-E) for the evaluation of children. Validity of the protocol, reliability of the examiners and agreement between them were analyzed, as also were the sensitivity, specificity and predictive values of the instrument. Methods: The sample consisted of videorecorded images of 50 children, 25 boys (mean age = 8.4 years, SD = 1.8) and 25 girls (mean age = 8.2 years, SD = 1.7) selected at random from 200 samples. Three speech therapists prepared for orofacial myofunctional evaluation participated as examiners (E). The OMES and OMES-E protocols were used for evaluation on different days. E1 evaluated all images, E2 analyzed children with recordings from 1 to 25 and E3 analyzed children with recordings from 26 to 50. The validity of OMES-E was analyzed by comparing the instrument to the OMES protocol using the Pearson correlation test complemented with the split-half reliability test (p < 0.05). The linear weighted Kappa coefficient of agreement (Kw`), the sensitivity, specificity and predictive values and the prevalence of OMD were calculated. Results: There was a statistically significant correlation between the OMES and OMES-E protocols (0.79 > r < 0.94, p < 0.01) and a significant test-retest correlation with the OMES-E (0.75 > r < 0.86, p < 0.01), with a reliability range of 0.86-0.93. The correlation and reliability coefficients between examiners were: E1 x E2 (r = 0.74, 0.84), E1 x E3 (r = 0.70, 0.83) (p < 0.01). Kw` coefficients with moderate and good strength predominated. The OMES-E protocol presented mean sensitivity = 0.91, specificity = 0.77, positive predictive value = 0.87 and negative predictive value = 0.85. The mean prevalence of OMD was 0.58. Conclusion: The OMES-E protocol is valid and reliable for orofacial myofunctional evaluation. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Prognostic factors and survival analysis in a sample of oral squamous cell carcinoma patients

Objectives. The aims of this report were to describe the 5-year overall survival (OS) in a group of oral squamous cell carcinoma (OSCC) patients and to investigate the effects of age, gender, anatomic localization, tumor evolution time, smoking and alcohol intake, nodal status, tumoral recurrences, histologic classification, p53 and p63 immunoexpression, human papillomavirus DNA presence, and treatment on the prognostic outcome. Study design. Survival curves were generated using Kaplan-Meier method, and univariate and multivariate analyses were made using the log rank test and Cox regression, respectively. Results. The 5-year OS was 28.6%, and the univariate analysis showed significant results for p53 and p63 immunoexpression, age, and anatomic localization. The Cox regression demonstrated poor OS for tumors with p53 immunoexpression and for patients aged over 60 years. There were also significant differences in survival depending on the anatomic localizations. Conclusion. These results highlight the influence of p53 immunoexpression, age, and anatomic localization in OSCC evolution. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008; 106: 685-95)

The role of surface sealants in the roughness of composites after a simulated toothbrushing test

Objectives: To evaluate the influence of two surface sealants (BisCover/Single Bond) and three application techniques (unsealed/conventional/co-polymerization) on the roughness of two composites (Filtek Z250/Z350) after the toothbrushing test. Methods: Seventy-two rectangular specimens (5 mm x 10 mm x 3 mm) were fabricated and assigned into 12 groups (n = 6). Each sample was subjected to three random roughness readings at baseline, after 100,000 (intermediate), and 200,000 (final) toothbrushing strokes. Roughness (R) at each stage was obtained by the arithmetic mean of the reading of each specimen. Sealant removal was qualitatively examined (optical microscope) and classified into scores (0-3). Data were analyzed by Student`s paired t-test, two-way ANOVA/Tukey`s test, and by Wilcoxon, Kruskal-Wallis and Miller`s test (alpha = 0.05). Results: Z250 groups at baseline did not differ statistically from each other. Unsealed Z350 at baseline had lower R values. All the unsealed groups presented gradual decrease in R from baseline to final brushing. From baseline to the inter-mediate stage, Z250 co-polymerized groups presented a significant reduction in R (score 3). Conventionally sealed groups had no significant changes in R (scores 2-0.8). From baseline to the intermediate stage, the conventionally sealed Z350 Single Bond group had an increase in R (score 1.5). In the final stage, all the conventionally sealed groups presented a reduction in R (scores 0.7-0). Co-polymerized Single Bond groups had a significant reduction in R (scores 2.5-2.7), and co-polymerized BisCover groups an increase in R (scores 2.8-3). Conclusions: At any brushing stage, sealed composites presented superior performance when compared with unsealed composites. (C) 2009 Elsevier Ltd. All rights reserved.

Factors influencing fluoride ingestion from dentifrice by children

Objective: This study assessed the percentage of the amount of dentifrice loaded onto the toothbrush that is ingested by children, taking into account age, the amount of dentifrice used during toothbrushing, and the dentifrice flavor. Methods: The sample consisted of 155 children of both genders attending public kindergartens and schools in Bauru, Brazil, divided into 5 groups (n = 30-32) of children aged 2, 3, 4, 5 and 6 years old. The dentifrices used were Sorriso(TM) (1219 ppm F, peppermint-flavored) and Tandy(TM) (959 ppm F, tutti-frutti-flavored). The assessment of fluoride intake from dentifrices was carried out six times for each child, using 0.3, 0.6, and 1.2 g of each dentifrice, following a random, crossover distribution. Brushing was performed by the children or their parents/caregivers according to the home habits and under the observation of the examiner. Fluoride present in the expectorant and on toothbrush was analyzed with an ion-specific electrode after HMDS-facilitated diffusion. Fluoride ingestion was indirectly derived. Results were analyzed by 3-way repeated-measures anova and Tukey`s tests (P < 0.05) using the percent dentifrice ingested as response variable. Results: Age and percent dentifrice ingested for both dentifrices, and the three amounts used were inversely related (P < 0.0001). Percent dentifrice ingested was significantly higher after the use of Tandy(TM) under all conditions of the study when compared with Sorriso(TM) (P < 0.0001). Significant differences were observed when brushing with 0.3 g when compared with 1.2 g, for both dentifrices tested (P < 0.05). Conclusions: The results indicate that all variables tested must be considered in preventive measures aiming to reduce the amount of fluoride ingested by young children.

Risk factors for dental erosion in a group of 12- and 16-year-old Brazilian schoolchildren

Background. Dental erosion is a multifactorial disease and is associated with dietary habits in infancy and adolescence. Aim. To investigate possible associations among dental erosion and diet, medical history and lifestyle habits in Brazilian schoolchildren. Design. The sample consisted of a random single centre cluster of 414 adolescents (12- and 16-years old) of both genders from private and public schools in Bauru (Brazil). The O`Brien [Children`s Dental Health in the United Kingdom, 1993 (1994) HMSO, London] index was used for dental erosion assessment. Data on medical history, rate and frequency of food and drinks consumption, and lifestyle habits were collected by a self-reported questionnaire. Odds ratios with 95% confidence intervals were used to assess the univariate relationships between variables. Analysis of questionnaire items was performed by multiple logistic regression analysis. The statistical significance level was set at 5%. Results. The erosion present group comprised 83 subjects and the erosion absent group 331. There were no statistically significant correlations among dental erosion and the consumption of food and drinks, medical history, or lifestyle habits. Conclusion. The results indicate that there was no correlation between dental erosion and the risk factors analysed among adolescents in Bauru/Brazil and further investigations are necessary to clarify the multifactorial etiology of this condition.

Elastic moduli of model random three-dimensional closed-cell cellular solids

Most cellular solids are random materials, while practically all theoretical structure-property results are for periodic models. To be able to generate theoretical results for random models, the finite element method (FEM) was used to study the elastic properties of solids with a closed-cell cellular structure. We have computed the density (rho) and microstructure dependence of the Young's modulus (E) and Poisson's ratio (PR) for several different isotropic random models based on Voronoi tessellations and level-cut Gaussian random fields. The effect of partially open cells is also considered. The results, which are best described by a power law E infinity rho (n) (1<n<2), show the influence of randomness and isotropy on the properties of closed-cell cellular materials, and are found to be in good agreement with experimental data. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

Long-term survivor mixture model with random effects: application to a multi-centre clinical trial of carcinoma

A mixture model incorporating long-term survivors has been adopted in the field of biostatistics where some individuals may never experience the failure event under study. The surviving fractions may be considered as cured. In most applications, the survival times are assumed to be independent. However, when the survival data are obtained from a multi-centre clinical trial, it is conceived that the environ mental conditions and facilities shared within clinic affects the proportion cured as well as the failure risk for the uncured individuals. It necessitates a long-term survivor mixture model with random effects. In this paper, the long-term survivor mixture model is extended for the analysis of multivariate failure time data using the generalized linear mixed model (GLMM) approach. The proposed model is applied to analyse a numerical data set from a multi-centre clinical trial of carcinoma as an illustration. Some simulation experiments are performed to assess the applicability of the model based on the average biases of the estimates formed. Copyright (C) 2001 John Wiley & Sons, Ltd.

Prevalence of Adverse Life Events, Depression and Suicidal Thoughts and Behaviour among a Community Sample of Young People aged 15-24 Years

Objective: To provide prevalence data on several key mental health indicators for young people aged 15 to 24 years. Methods: A cross-sectional household survey, using telephone recruitment followed by a postal pencil-and-paper questionnaire. The overall response rate was 67.3%. Results: Difficulties with interpersonal relationships are common causes of distress for young people, in particular problems with parents, problems with friends and relationship break-ups. Depressive symptomatology is common among young people with approximately one in eight males and one in four females reporting current depressive symptomatology. One in three young people reported that they had had suicidal thoughts at some time in the past, 1.2% of young people reported that they had made a plan on how to kill themselves in the four-week period prior to completing the survey and 6.9% of young people reported that they had tried to kill themselves at some time during their life time (4.2% of males and 9.0% of females). Conclusions and implications: The prevalence figures for the various mental health indicators presented in this paper represent good baseline information upon which to examine the progress over time of interventions designed to improve the mental health of young people.