Potential Health Risks of Lead Exposure from Early Life through Later Life: Implications for Public Health Education.

Lead (Pb) exposure has been a serious environmental and public health problem throughout the world over the years. The major sources of lead in the past were paint and gasoline before they were phased out due to its toxicity. Meanwhile, people continue to be exposed to lead from time to time through many other sources such as water, food, soil and air. Lead exposure from these sources could have detrimental effects on human health, especially in children. UNICEF reported that approximately 800 million children have blood lead levels (BLLs) at or above 5 micrograms per deciliter (µg/dL) globally. This paper reports on the potential risks of lead exposure from early life through later life. The articles used in this study were searched from databases such as Springer, Science Direct, Hindawi, MDPI, Google Scholar, PubMed and other academic databases. The levels of lead exposure in low income and middle-income countries (LMICs) and high-income countries (HICs) were reported, with the former being more affected. The intake of certain nutrients could play an essential role in reducing (e.g., calcium and iron) or increasing (e.g., high fat foods) lead absorption in children. Elevated blood lead levels may disturb the cells' biological metabolism by replacing beneficial ions in the body such as calcium, magnesium, iron and sodium. Once these ions are replaced by lead, they can lead to brain disorders, resulting in reduced IQ, learning difficulties, reduced attention span and some behavioral problems. Exposure to lead at an early age may lead to the development of more critical problems later in life. This is because exposure to this metal can be harmful even at low exposure levels and may have a lasting and irreversible effect on humans. Precautionary measures should be put in place to prevent future exposure. These will go a long way in safeguarding the health of everyone, most especially the young ones.

Learning styles and approaches to learning mathematics of students majoring in elementary education: a three-year study.

The goal of this 3-yr. study was to explore the learning styles and approaches to learning mathematics of elementary education majors. Two questionnaires, the Learning Style Inventory and the Approaches to Learning Mathematics Questionnaire, were administered to 149 women and 32 men (M = 20.1 yr., SD. = 2.1; range = 18-31). All were in their first or second years of college and enrolled in Mathematics for Elementary School Teachers at a Midwestern U.S. university. Results on the Learning Style Inventory indicated that a majority scored as either Accommodators, i.e., they primarily followed learning modes involving Active Experimentation and Concrete Experience, or as Divergers, i.e., approaching learning by focusing on Concrete Experience and Reflective Observation. A weak but statistically significant association was observed on the Approaches questionnaire between the Surface Approach and Reflective Observation.

Differences in university students' attitudes and anxiety about statistics.

The Statistics Anxiety Rating Scale and the Attitudes Toward Statistics questionnaire were administered to 226 university of technology students. The former scale measures anxiety about learning statistics in terms of Worth of Statistics, Interpretation Anxiety, Test and Class Anxiety, Computational Self-concept, Fear of Asking for Help, and Fear of Statistics Teachers. The latter measures attitudes toward use of statistics and statistics course for which a student was registered. These African students were enrolled in Taxation, Marketing, or Accounting. Participants took a required course in statistics intended to improve statistical skills. There were 150 women and 57 men, chosen because they had no previous mathematics learning. Students' ages ranged between 16 and 26 years (M = 20.1, SD = 2.0). There were no statistically significant sex differences on attitudes and anxiety toward statistics, but there were significant differences among areas of study programs.

Exploring high school science students' perceptions of parental involvement in their education.

This exploratory study describes high school students' perceptions of their parents' involvement in their education and in relation to school achievement. A new 12-item Parental Involvement Scale was used to measure parents' involvement in curricular and extracurricular activities and using exploratory analyses to estimate the scale's properties. Exploratory analysis resulted in the reduction of the 12 items to 8, with an internal consistency (Cronbach alpha) .82. Grade 12 science students indicated that their less educated parents were involved in activities pertaining to their learning; however, high perceived parental involvement in curricular activities was related to low achievement. It is recommended that further exploratory analyses be undertaken to examine the reported two-dimensional model of the Parental Involvement Scale.

Combining reliability coefficients: toward reliability generalization of the conceptions of mathematics questionnaire.

The combined coefficient alpha from studies reporting the reliability of scores using the Conceptions of Mathematics Questionnaire were computed. Five studies comprising 898 participants were evaluated. A test of differences among the independent coefficients alpha was statistically significant (chi42= 10.38, p = .04) for the Fragmented and (chi42 = 11.58, p = .02) for the Cohesive subscales. Post hoc comparisons showed the difference (F129,299 = 1.50, p=.003) was between Australia and Nigeria for the former and (F155,157 = 1.54, p= .004) between South Africa and the United States for the latter alpha values. A one-way analysis of variance, testing for homogeneity among means within each subscale, indicated that these were homogeneous because the measure of the strength of association accounted for 10% of variability. As reliability coefficients were from homogeneous samples and alpha values were not different, the combined reliability is the best estimate of the population reliability for each subscale.

Attitudes of university precalculus students toward mathematics.

To investigate the attitudes of 200 university students (83% freshmen) toward mathematics, a questionnaire was administered to report on their attitudes toward mathematics. Analysis indicated that students studying precalculus had a somewhat positive attitude toward mathematics.

Nigerian undergraduate education majors' conceptions of mathematics.

The Conceptions of Mathematics Questionnaire by Crawford, et al. was administered to 130 southwest Nigerian undergraduate education majors who took mathematics. Coefficient alphas of .86 and .84 for the Fragmented and Cohesive subscales were similar to prior values. There were no statistically significant mean differences between men and women or between undergraduates taking mathematics with science and nonscience topics.

Psychometric characteristics of the Science Teaching Efficacy Belief Inventory in South Africa.

The psychometric properties of the Science Teaching Efficacy Belief Inventory are reported, based on responses of 200 (88 men and 112 women) elementary science teachers in the Eastern Cape, South Africa. Previous factor analytic studies of this inventory have identified a two-factor solution but this has not been investigated in a South African context. The reliability estimated as internal consistency (Cronbach alpha) was .87. Principal components analysis with varimax rotation indicated a two-factor solution accounting for 38.1% of variance, with Cronbach alphas of .92 and .73 for the Personal Science Teaching Efficacy Belief subscale (Factor 1) and the Science Teaching Outcome Expectancy subscale (Factor 2), respectively. Principal components analysis of the Science Teaching Efficacy Belief Inventory yielded two conceptually meaningful components, similar to those reported in literature. Although one item did not meet the conditions for acceptance, this inventory may be useful in understanding science teachers' efficacy beliefs in South Africa. These particular findings are preliminary but hopeful. Studies using confirmatory analysis to address the cross-national invariance of this inventory are needed.

Sex differences in self-efficacy beliefs of elementary science teachers.

The Science Teaching Efficacy Belief Inventory developed by Riggs and Enoch was administered to 88 men and 112 women, elementary science teachers in the Eastern Cape, South Africa. Significant mean sex differences (t=4.55, p<.01) were observed on the Personal subscale but not on the General subscale. This result has major implications for education planners and administrators employing female teachers whose cultural and educational experiences may not have prepared them as well as their male peers for teaching science. It is concluded that female teachers need support to change their beliefs about self-efficacy regarding teaching science. The discussion also suggests possible directions for research.