Differences between younger and older adults in the structure of suicidal intent and its correlates

OBJECTIVE: To analyze differences in the variables associated with severity of suicidal intent and in the main factors associated with intent when comparing younger and older adults. DESIGN: Observational, descriptive cross-sectional study. SETTING: Four general hospitals in Madrid, Spain. PARTICIPANTS: Eight hundred seventy suicide attempts by 793 subjects split into two groups: 18-54 year olds and subjects older than 55 years. MEASUREMENTS: The authors tested the factorial latent structure of suicidal intent through multigroup confirmatory factor analysis for categorical outcomes and performed statistical tests of invariance across age groups using the DIFFTEST procedure. Then, they tested a multiple indicators-multiple causes (MIMIC) model including different covariates regressed on the latent factor "intent" and performed two separate MIMIC models for younger and older adults to test for differential patterns. RESULTS: Older adults had higher suicidal intent than younger adults (z = 2.63, p = 0.009). The final model for the whole sample showed a relationship of intent with previous attempts, support, mood disorder, personality disorder, substance-related disorder, and schizophrenia and other psychotic disorders. The model showed an adequate fit (chi²[12] = 22.23, p = 0.035; comparative fit index = 0.986; Tucker-Lewis index = 0.980; root mean square error of approximation = 0.031; weighted root mean square residual = 0.727). All covariates had significant weights in the younger group, but in the older group, only previous attempts and mood disorders were significantly related to intent severity. CONCLUSIONS: The pattern of variables associated with suicidal intent varies with age. Recognition, and treatment of geriatric depression may be the most effective measure to prevent suicidal behavior in older adults.

The effect of participation in a ``Greening the BCC Curriculum'' workshop series on the environmental literacy of a community college faculty

The purpose of this study was to develop a series of workshops designed to raise the environmental literacy of a community college faculty and facilitate infusion of an environmental perspective into the courses they teach. Data was gathered on the effect of the workshops on the level of environmental literacy of the participants as well as the persistence of any observed effect. How faculty infused an environmental perspective into their courses was also explored.^ The workshop model was developed by reviewing adult learning and change theories, case studies of workshops at other colleges, environmental education research, and results of a pilot study. Content, organization, and delivery methods from these sources were selected and integrated to create the 14 components of the model employed by the workshops in this study.^ Forty-two faculty from the North Campus of Broward Community College participated in the study. The 20 workshop participants from seven academic departments attended seven two hour workshops during the fall term of 1996, and implemented projects to infuse environmental topics into their courses the following term. A quasi-experimental pretest-posttest-delayed posttest nonequivalent control group design was employed in which the 22 members of the control group who did not attend the workshops were administered the Wisconsin Environmental Survey at the same time as the workshop participants (immediately before the first workshop, immediately following the last workshop, and four months following the completion of the workshop series). This instrument, an adaption of the Wisconsin High School Student Environmental Survey, yielded three measures of environmental literacy: Affective, Behavior, and Cognitive Subscale scores.^ The repeated measures MANOVA performed using the scores of the two groups on the three administrations of WES revealed a significant interaction for group by time, so repeated measures ANOVA were performed for each of the three subscales to investigate the interaction. Tukey-HSD post hoc comparisons indicated that for all three subscale scores, the two groups were not significantly different on the pretest, but on the posttest and the delayed posttest, the workshop participants demonstrated significantly higher levels of environmental literacy. All statistical tests were performed at $\alpha$ =.05. ^

Intercollegiate athletics and college rankings: An analysis of the relationship between athletic success and the U.S. News and World Report college rankings

The purpose of this study was to gain a greater understanding of the relationship between athletic success of football and men's basketball and the U.S. News and World Report (USNWR) college rankings. There has been consistent debate among researchers who study institutional quality about whether intercollegiate athletics enhances reputation. This study is similar to other studies attempting to measure the relationship between athletic success and possible indirect benefits to the university from athletics, such as increased admissions applications and increased alumni donations and giving. This study offered a more nuanced model for measuring athletic success, a concept that has been difficult to measure quantitatively. The method used here also measured change over time (in this case, from year-to-year over an eleven year period). The research questions for this study were (a) is there a correlation between athletic success and the USNWR college ranking; and (b) is there a correlation in the change from year-to-year in athletic success with the change from year-to-year in the USNWR college rankings? Spearman Rho correlation and ANOVA tests were used to answer these research questions. The results from the statistical tests demonstrated little correlation between athletic success, whether in football or men's basketball, with the USNWR college rankings. Although the relationships were weak, men's basketball success consistently demonstrated a stronger relationship than football success. This finding differed from what is most often found in the literature, which often favors football success. The ANOVA test results did reveal some results that suggest athletic participation is a factor in the USNWR college rankings. As the debate continues about whether intercollegiate athletics enhances reputation, and as colleges and universities continue spending enormously on athletics, a keener understanding about the possible indirect benefits to the university from athletic programs is needed. The "advertising" provided by spectator sports such as football and men's basketball is often assumed by university leaders to present substantial indirect benefits for the university. However, the existing research along with this study provides little evidence of such opportunities.

A research platform for artificial neural networks with applications in pediatric epilepsy

This dissertation established a state-of-the-art programming tool for designing and training artificial neural networks (ANNs) and showed its applicability to brain research. The developed tool, called NeuralStudio, allows users without programming skills to conduct studies based on ANNs in a powerful and very user friendly interface. A series of unique features has been implemented in NeuralStudio, such as ROC analysis, cross-validation, network averaging, topology optimization, and optimization of the activation function’s slopes. It also included a Support Vector Machines module for comparison purposes. Once the tool was fully developed, it was applied to two studies in brain research. In the first study, the goal was to create and train an ANN to detect epileptic seizures from subdural EEG. This analysis involved extracting features from the spectral power in the gamma frequencies. In the second application, a unique method was devised to link EEG recordings to epileptic and nonepileptic subjects. The contribution of this method consisted of developing a descriptor matrix that can be used to represent any EEG file regarding its duration and the number of electrodes. The first study showed that the inter-electrode mean of the spectral power in the gamma frequencies and its duration above a specific threshold performs better than the other frequencies in seizure detection, exhibiting an accuracy of 95.90%, a sensitivity of 92.59%, and a specificity of 96.84%. The second study yielded that Hjorth’s parameter activity is sufficient to accurately relate EEG to epileptic and non-epileptic subjects. After testing, accuracy, sensitivity and specificity of the classifier were all above 0.9667. Statistical tests measured the superiority of activity at over 99.99 % certainty. It was demonstrated that (1) the spectral power in the gamma frequencies is highly effective in locating seizures from EEG and (2) activity can be used to link EEG recordings to epileptic and non-epileptic subjects. These two studies required high computational load and could be addressed thanks to NeuralStudio. From a medical perspective, both methods proved the merits of NeuralStudio in brain research applications. For its outstanding features, NeuralStudio has been recently awarded a patent (US patent No. 7502763).

Predictors of adolescent sexual intentions and behavior: Attitudes, parenting, and neighborhood risk

The current study was a cross-sectional examination of data collected during an HIV risk reduction intervention in south Florida. The purpose of the study was to explore the relationships between neighborhood stress, parenting, attitudes, and adolescent sexual intentions and behavior. The Theory of Planned Behavior was used as a model to guide variable selection and propose an interaction pathway between predictors and outcomes. Potential predictor variables measured for adolescents ages 13–18 (n=196) included communication about sex, parent-family connectedness, parental presence, parent-adolescent activity participation, attitudes about sex and condom use, neighborhood disorder, and exposure to violence. Outcomes were behavioral intentions and sexual behavior for the previous eight months. Neighborhood data was supplemented with ZIP Code level data from regional sources and included median household income, percentage of minority and Hispanic residents, and number of foreclosures. Statistical tests included t-tests, Pearson's correlations, and hierarchical linear regressions. Results showed that males and older adolescents reported less positive behavioral intentions than females and adolescents younger than 16. Intentions were associated with condom attitudes, sexual attitudes, and parental presence; unprotected sexual behavior was associated with parental presence. The best fit model for intentions included gender, sexual attitudes, condom attitudes, parental presence, and neighborhood disorder. The unsafe sexual behavior model included whether the participant lived with both natural parents in the previous year, and the percent of Hispanic residents in the neighborhood. Study findings indicate that more research on adolescent sexual behavior is warranted, specifically examining the differentials between variables that affect intentions and those that affect behavior. A focus on gender and age differences during intervention development may allow for better targeting and more efficacious interventions. Adding peer and media influences to the framework of attitudes, parenting, and neighborhood may offer more insight into patterns of adolescent sexual behavior risk.

A Research Platform for Artificial Neural Networks with Applications in Pediatric Epilepsy

This dissertation established a state-of-the-art programming tool for designing and training artificial neural networks (ANNs) and showed its applicability to brain research. The developed tool, called NeuralStudio, allows users without programming skills to conduct studies based on ANNs in a powerful and very user friendly interface. A series of unique features has been implemented in NeuralStudio, such as ROC analysis, cross-validation, network averaging, topology optimization, and optimization of the activation function’s slopes. It also included a Support Vector Machines module for comparison purposes. Once the tool was fully developed, it was applied to two studies in brain research. In the first study, the goal was to create and train an ANN to detect epileptic seizures from subdural EEG. This analysis involved extracting features from the spectral power in the gamma frequencies. In the second application, a unique method was devised to link EEG recordings to epileptic and non-epileptic subjects. The contribution of this method consisted of developing a descriptor matrix that can be used to represent any EEG file regarding its duration and the number of electrodes. The first study showed that the inter-electrode mean of the spectral power in the gamma frequencies and its duration above a specific threshold performs better than the other frequencies in seizure detection, exhibiting an accuracy of 95.90%, a sensitivity of 92.59%, and a specificity of 96.84%. The second study yielded that Hjorth’s parameter activity is sufficient to accurately relate EEG to epileptic and non-epileptic subjects. After testing, accuracy, sensitivity and specificity of the classifier were all above 0.9667. Statistical tests measured the superiority of activity at over 99.99 % certainty. It was demonstrated that 1) the spectral power in the gamma frequencies is highly effective in locating seizures from EEG and 2) activity can be used to link EEG recordings to epileptic and non-epileptic subjects. These two studies required high computational load and could be addressed thanks to NeuralStudio. From a medical perspective, both methods proved the merits of NeuralStudio in brain research applications. For its outstanding features, NeuralStudio has been recently awarded a patent (US patent No. 7502763).

Avaliação da qualidade da assistência à mulher e ao filho durante o parto normal

The practices developed in the everyday life of obstetric services are sometimes out of step with the recommendations of the public health policies. Accordingly, this research had the objective of assessing the quality of the care provided to women and children during cases of natural childbirth in municipal public maternity wards of the city of Natal/RN, Brazilian Northeast. We developed a cross-sectional and quantitative study in two maternity wards that provide care actions to pregnant women at regular risk (maternity wards A and B). The participants were 314 puerperal women who were treated during the period between April and July 2014, whose children were born alive, through transpelvic way, with spontaneous or induced beginning of labor and that showed physical and emotional conditions to respond to the proposed questions. The data collection instrument was constructed on the basis of the recommendations of the World Health Organization focused on the care of normal childbirth and validated by skilled judges, and the final version has obtained optimum agreement (k = 0,96; IVC = 0,99). Associated with these recommendations, we used three indicators: percentage of women with induced labor or subjected to elective cesarean section (Indicator A); percentage of women served by a qualified health professional during labor and childbirth (Indicator B); and Bologna Index (Indicator C). The research obtained a favorable opinion of the Research Ethics Committee from the Federal University of Rio Grande do Norte, under the nº 562.313 and Certificate of Presentation for Ethics Appreciation: 25958513.0.0000.5537. The analysis of categories related to the recommendations of the World Health Organization was conducted by means of absolute and relative frequency and the Chi-square Pearson’s and Fisher’s exact tests made the comparison of the differences observed between the two maternity wards. Furthermore, we calculated the percentage of the indicators A and B and with the results of the Indicator C, the quality was assessed as follows: the closer to 5, the better will be the quality, and the closer to 0, the worst will be the quality, and the Mann-Whitney U test was used to compare the differences of the obtained averages. The significance level of 5% was considered in all statistical tests. The differences between the maternity wards were identified with regard to the provision of liquids orally (p=0,018), stimulus for non-supine positions (p=0,002), existence of partograph (p=0,001), support or welcoming by health professionals (p= 0,047), intravenous infusion (p<0,001), supine position (p<0,001), use of oxytocin (p<0,001), food and liquid restriction (p= 0,002) and, lastly, the fact of the touch is performed by more than 1 examiner (p=0,011). The indicators A and B showed percentages of 13,09% and 100%, respectively. The overall average of the Indicator C was equal to 2,07 (± 0,74). There was a statistically significant difference between the averages of the maternity wards (p<0,001). The care actions provided during the process of labor and childbirth is inappropriate, especially in the maternity ward B. It is necessary to implement improvements and redesign the obstetric model in force

Análise comparativa da imunoexpressão do IMP-3 e Ki-67 em queilites actínicas e carcinoma epidermóide de lábio inferior

Epithelial changes observed in actinic cheilitis (AC) and squamous cell carcinoma of the lower lip (LLSCC) are mainly caused by chronic exposure to ultraviolet rays (UV) and are studied using different immunohistochemical markers trying to evaluate the process of carcinogenesis. The objective of this study was to comparatively evaluate the expression of Ki-67 proteins and IMP-3 in AC and LLSCC to contribute with additional information on carcinogenesis in lower lip. A total of 33 cases of AC and 33 cases of LLSCC were studied, analyzed the clinical and pathological features and immunostaining of Ki-67 and IMP-3. Immunohistochemical analysis of Ki-67 was made through the determination of the proliferation index (PI) and subsequent classification of the cases according to the scores: 0 (0% positive cells) +1 (≤30%) + 2 (> 30% and ≤60%) and +3 (> 60%). For statistical tests cases were classified as unmarked (score 0), low expression (score +1) and high expression (scores +2 and +3). For the expression of IMP-3, the percentage of immunostained epithelial cells was established, and assigned scores: 0 (corresponding to 0%), +1 (up to 30% of positive cells); +2 (From 30% to 60% of immunostained cells) and +3 (over 60% of positive cells). Statistical tests chi-square test, Mann-Whitney and Wilcoxon were used. The significance level was 5%. Most AC chaos was male (78.8%) with mean age of 50 years and cases of LLSCC also were male (69.89%) with an average of 62 years. The Ki-67 was expressed in all cases of AC and in cases of LLSCC, predominantly in the two injuries the score 2, corresponding to 81.8% of cases in ACs and 54.5% in the CELI. The expression of IMP-3 in ACs occurred in 72.7% of cases, predominantly in 36.3% of LLSCC cases score 1. Already in the IMP-3 was expressed in 60.6% of cases, especially in 27.3% of the score of the cases 3. These results allow us to conclude that the expression of IMP3 and proliferative activity are early events in carcinogenesis independently lower lip state of change.

Análise de tendência e caracterização sazonal e interanual da evapotranspiração de referência para o sudoeste da amazônia brasileira: Acre, Brasil

The objective of this research was to investigate monthly climatological, seasonal, annual and interdecadal of the reference evapotranspiration (ETo) in Acre state in order to better understand its spatial and temporal variability and identify possible trends in the region. The study was conducted with data from Rio Branco municipalities, the state capital, Tarauacá and Cruzeiro do Sul considering a 30-year period (1985-2014), from monthly data from weather stations surface of the National Institute of Meteorology. The methodology was held, first, the consistency of meteorological data. Thus, it was made the gap filling in the time series by means of multivariate techniques. Subsequently were performed statistical tests trend (Mann-Kendall) and homogeneity, by Sen's estimator of the magnitude of this trend is estimated, as well as computational algorithms containing parametric and non-parametric tests for two samples to identify from that year the trend has become significant. Finally, analysis of variance technique (ANOVA) was adopted in order to verify whether there were significant differences in average annual evapotranspiration between locations. The indirect method of Penman-Montheith parameterized by FAO was used to calculate the ETo. The results of this work through examination of the descriptive statistics showed that the ETo the annual average was 3.80, 2.92 and 2.86 mm day-1 year, to Rio Branco, Tarauacá and Cruzeiro do Sul, respectively. Featuring quite remarkable seasonal pattern with a minimum in June and a maximum in October, with Rio Branco to town one with the strongest signal (amplitudes) on the other hand, the Southern Cross presented the highest variability among the studied locations. By ANOVA it was found that the average annual statistically different for a significance level of 1% between locations, but the annual average between Cruzeiro do Sul and Tarauacá no statistically significant differences. For the three locations, the 2000s was the one with the highest ETo values associated with warmer waters of the North Atlantic basin and the 80s to lower values, associated with cooler waters of this basin. By analyzing the Mann-kendall and Sen estimator test, there was a trend of increasing the seasonal reference evapotranspiration (fall, winter and spring) on the order of 0.11 mm per decade and that from the years of 1990, 1996 and 2001 became statistically significant to the localities of Cruzeiro do Sul Tarauacá and Rio Branco, respectively. For trend analysis of meteorological parameters was observed positive trend in the 5% level of significance, for average temperature, minimum temperature and solar radiation.

Distribuição de derivados de petróleo por redes de polidutos: uma abordagem através de algoritmos evolucionários híbridos para um problema triobjetivo

An important problem faced by the oil industry is to distribute multiple oil products through pipelines. Distribution is done in a network composed of refineries (source nodes), storage parks (intermediate nodes), and terminals (demand nodes) interconnected by a set of pipelines transporting oil and derivatives between adjacent areas. Constraints related to storage limits, delivery time, sources availability, sending and receiving limits, among others, must be satisfied. Some researchers deal with this problem under a discrete viewpoint in which the flow in the network is seen as batches sending. Usually, there is no separation device between batches of different products and the losses due to interfaces may be significant. Minimizing delivery time is a typical objective adopted by engineers when scheduling products sending in pipeline networks. However, costs incurred due to losses in interfaces cannot be disregarded. The cost also depends on pumping expenses, which are mostly due to the electricity cost. Since industrial electricity tariff varies over the day, pumping at different time periods have different cost. This work presents an experimental investigation of computational methods designed to deal with the problem of distributing oil derivatives in networks considering three minimization objectives simultaneously: delivery time, losses due to interfaces and electricity cost. The problem is NP-hard and is addressed with hybrid evolutionary algorithms. Hybridizations are mainly focused on Transgenetic Algorithms and classical multi-objective evolutionary algorithm architectures such as MOEA/D, NSGA2 and SPEA2. Three architectures named MOTA/D, NSTA and SPETA are applied to the problem. An experimental study compares the algorithms on thirty test cases. To analyse the results obtained with the algorithms Pareto-compliant quality indicators are used and the significance of the results evaluated with non-parametric statistical tests.

Influência da paridade, do tipo de parto e do nível de atividade física sobre a musculatura do assoalho pélvico em mulheres na pós-menopausa

The post-menopause stage is characterized by hormonal and organic alterations of ovarian failure. One of the most important of these is muscles alterations of the pelvic floor (MPF). According to current literature, in young women gynecological and obstetric factors, as well as lifestyles and habits influence that loss of function. However, there is still uncertainty about the influence of those variables in the MPF functions in post-menopause women. Thus, this study aimed at seeing if there is an influence from number of births, the type of birth and the level of physical activity on the MPF of post-menopause women. Another objective of this study was to compare MPF force in women who had had vaginal births with those who had been subjected to cesarean sections, those with different levels of physical activity and those with artificial and natural menopause in the initial and latter stages. Furthermore, the test of muscular force was compared to perineometry. Using observational, analytical and transversal observations, 100 women in the post-menopausal stage of life, between the ages of 45 and 65, were examined. They were divided according to the menopausal stage into three groups: women who had undergone hysterectomies, those in the initial stages of postmenopause and those in the late stage of postmenpause. The patients were questioned about social, demographic, gynecological and obstetric factors. All the volunteers were submitted to a physical examination where their height and weight were measured to arrive at the corporal mass index and their waist measurements were taken. The evaluation of the pelvic floor was conducted with muscular force tests and perineometry. These results were analyzed with statistical description and ANOVA statistical tests, multiple regression and Kolmogorov-Smirnov evaluations. The results showed homogeneity with regard to social demographic and anthropometric characteristics among the women in the final test sample (n=85). It was also seen that most of the women in all three groups were married (p=0.51) and catholic (p=0.13). The average per capital income varied between $R585.47 (+/-466.67) and $R1,271.83 (+/-1,748.95), with no significant difference between the groups (p=0.05). The G>6 group presented an average age between 58.95 (+/-3.96) which was significantly greater that the G<6 group´s average age (53.21+/- 3.88) (p=0.000). There was no difference between the groups´ anthropometric characteristics of weight (p=0.32), height (p=0.72) and corporal mass index (p=0.34), nor in the waist measurements (p=0.33). Furthermore, no significant difference was noted in the MPF function of women who had had normal births, cesarean sections or a combination of the two (TFM p=0.897; perineum measurement p=0.502). Likewise, no differences were seen in the MPF function of women who had one, two to three or four or more births (TFM p=0.28, perineum measurement p=0.13). Finally, no difference was perceived among those with different levels of physical activity (TFM p=0.663; perineum measurement p=0.741). Therefore, we found that the type of delivery, number of births and physical activity had no influence on the muscular function of the pelvic floor among the women studied. It is believed that decline in muscular function in post-menopause women is fundamentally related to the process of aging.

Investigações sobre técnicas de arquivamento para otimizadores multiobjetivo

Multi-objective problems may have many optimal solutions, which together form the Pareto optimal set. A class of heuristic algorithms for those problems, in this work called optimizers, produces approximations of this optimal set. The approximation set kept by the optmizer may be limited or unlimited. The benefit of using an unlimited archive is to guarantee that all the nondominated solutions generated in the process will be saved. However, due to the large number of solutions that can be generated, to keep an archive and compare frequently new solutions to the stored ones may demand a high computational cost. The alternative is to use a limited archive. The problem that emerges from this situation is the need of discarding nondominated solutions when the archive is full. Some techniques were proposed to handle this problem, but investigations show that none of them can surely prevent the deterioration of the archives. This work investigates a technique to be used together with the previously proposed ideas in the literature to deal with limited archives. The technique consists on keeping discarded solutions in a secondary archive, and periodically recycle these solutions, bringing them back to the optimization. Three methods of recycling are presented. In order to verify if these ideas are capable to improve the archive content during the optimization, they were implemented together with other techniques from the literature. An computational experiment with NSGA-II, SPEA2, PAES, MOEA/D and NSGA-III algorithms, applied to many classes of problems is presented. The potential and the difficulties of the proposed techniques are evaluated based on statistical tests.

Investigações sobre técnicas de arquivamento para otimizadores multiobjetivo

Multi-objective problems may have many optimal solutions, which together form the Pareto optimal set. A class of heuristic algorithms for those problems, in this work called optimizers, produces approximations of this optimal set. The approximation set kept by the optmizer may be limited or unlimited. The benefit of using an unlimited archive is to guarantee that all the nondominated solutions generated in the process will be saved. However, due to the large number of solutions that can be generated, to keep an archive and compare frequently new solutions to the stored ones may demand a high computational cost. The alternative is to use a limited archive. The problem that emerges from this situation is the need of discarding nondominated solutions when the archive is full. Some techniques were proposed to handle this problem, but investigations show that none of them can surely prevent the deterioration of the archives. This work investigates a technique to be used together with the previously proposed ideas in the literature to deal with limited archives. The technique consists on keeping discarded solutions in a secondary archive, and periodically recycle these solutions, bringing them back to the optimization. Three methods of recycling are presented. In order to verify if these ideas are capable to improve the archive content during the optimization, they were implemented together with other techniques from the literature. An computational experiment with NSGA-II, SPEA2, PAES, MOEA/D and NSGA-III algorithms, applied to many classes of problems is presented. The potential and the difficulties of the proposed techniques are evaluated based on statistical tests.

Classificação de nódulos pulmonares em imagens tomográficas utilizando redes neurais artificiais em cascata

Lung cancer is the most common of malignant tumors, with 1.59 million new cases worldwide in 2012. Early detection is the main factor to determine the survival of patients affected by this disease. Furthermore, the correct classification is important to define the most appropriate therapeutic approach as well as suggest the prognosis and the clinical disease evolution. Among the exams used to detect lung cancer, computed tomography have been the most indicated. However, CT images are naturally complex and even experts medical are subject to fault detection or classification. In order to assist the detection of malignant tumors, computer-aided diagnosis systems have been developed to aid reduce the amount of false positives biopsies. In this work it was developed an automatic classification system of pulmonary nodules on CT images by using Artificial Neural Networks. Morphological, texture and intensity attributes were extracted from lung nodules cut tomographic images using elliptical regions of interest that they were subsequently segmented by Otsu method. These features were selected through statistical tests that compare populations (T test of Student and U test of Mann-Whitney); from which it originated a ranking. The features after selected, were inserted in Artificial Neural Networks (backpropagation) to compose two types of classification; one to classify nodules in malignant and benign (network 1); and another to classify two types of malignancies (network 2); featuring a cascade classifier. The best networks were associated and its performance was measured by the area under the ROC curve, where the network 1 and network 2 achieved performance equal to 0.901 and 0.892 respectively.

Supporting Metacognitive Development in Early Science Education: Exploring Elementary Teachers' Beliefs and Practices in Metacognition

Metacognition is the understanding and control of cognitive processes. Students with high levels of metacognition achieve greater academic success. The purpose of this mixed-methods study was to examine elementary teachers’ beliefs about metacognition and integration of metacognitive practices in science. Forty-four teachers were recruited through professional networks to complete a questionnaire containing open-ended questions (n = 44) and Likert-type items (n = 41). Five respondents were selected to complete semi-structured interviews informed by the questionnaire. The selected interview participants had a minimum of three years teaching experience and demonstrated a conceptual understanding of metacognition. Statistical tests (Pearson correlation, t-tests, and multiple regression) on quantitative data and thematic analysis of qualitative data indicated that teachers largely understood metacognition but had some gaps in their understanding. Participants’ reported actions (teaching practices) and beliefs differed according to their years of experience but not gender. Hierarchical multiple regression demonstrated that the first block of gender and experience was not a significant predictor of teachers' metacognitive actions, although experience was a significant predictor by itself. Experience was not a significant predictor once teachers' beliefs were added. The majority of participants indicated that metacognition was indeed appropriate for elementary students. Participants consistently reiterated that students’ metacognition developed with practice, but required explicit instruction. A lack of consensus remained around the domain specificity of metacognition. More specifically, the majority of questionnaire respondents indicated that metacognitive strategies could not be used across subject domains, whereas all interviewees indicated that they used strategies across subjects. Metacognition was integrated frequently into Ontario elementary classrooms; however, metacognition was integrated less frequently in science lessons. Lastly, participants used a variety of techniques to integrate metacognition into their classrooms. Implications for practice include the need for more professional development aimed at integrating metacognition into science lessons at both the Primary and Junior levels. Further, teachers could benefit from additional clarification on the three main components of metacognition and the need to integrate all three to successfully develop students’ metacognition.