The bacteria associated with contamination of ready-to-eat (RTE) cooked rice in Lagos, Nigeria were studied using standard microbiological methods. The objective of this study was to investigate the distribution of pathogenic bacteria recovered from RTE cooked rice in Lagos, assess bacteria load in the contaminated RTE cooked rice and evaluate their microbial quality. The microbial load of the RTE cooked rice ranged from 1.5 ± 0.29x 10 4 -4.8 ± 0.46x 10 6 cfu/g for three markets. A further test revealed that the average bacteria counts at Ketu was significantly different from those at Yaba and Odogunyan. However it was found that counts at Yaba and Odogunyan were not significantly different. Based on the specification by the International Microbiological Standard limits for Foods (IMSF), the levels of contamination of the total samples that were above and below microbiological acceptable limit were 91.7% and 8.3% respectively. The predominant pathogenic bacteria associated with contamination of the RTE cooked rice samples were identified as Staphylococcus aureus, Brahamella sp, Enterobacter aerogenes and Salmonella typhi. Out of a total of 36 RTE cooked rice samples analyzed, Enterobacter aerogenes 36 (100%) had the highest occurrence followed in descending order by Staphylococcus aureus 33 (91.7%), Brahamella sp. 29 (80.6%) and Salmonella sp. 25(69%). The results indicated that most of the RTE cooked rice samples examined in this study did not meet bacteriological quality standards. These findings suggest that the presence of food pathogens in RTE rice hawked in our local markets may pose serious potential health risks to the consumers in the public.

This study focuses on fostering students' cognitive achievement using students-concept maps and demonstration in chemistry. A pre-test, post-test control groups 3 x 3 x 2 factorial design was employed. A total of two hundred and forty eight senior secondary two students drawn from three public secondary schools in Ogun state of Nigeria participated in the study. Stratified random sampling technique was used in drawing the schools. Intact classes of students were used for the study. Three research questions and three hypotheses guided the study. Treatment that lasted for four weeks involved teaching redox reaction concepts to experimental groups using students-directed concept mapping, demonstration while the control group was taught using lecture method. Test of Knowledge in Redox Reaction (TKRR) was the instrument for data collection. Mean and standard deviation were used to answer the research questions while the hypotheses were tested with Analysis of covariance (ANCOVA). Results revealed that there was significant difference in the cognitive achievement of students taught using students-directed concept mapping, demonstration and lecture method. Experimental groups' achievement was significantly better than those taught using lecture method. Also ability level is significant factor on students' cognitive achievement in Redox reaction. However, no significant difference was found on the effect of gender on cognitive achievement. Based on the findings, the use of students-directed concept mapping and demonstration strategies to foster cognitive achievement in difficult concept like Redox reaction in chemistry was recommended to chemistry teachers.

The bacteria associated with contamination of ready-to-eat (RTE) fruit salad samples obtained from four markets namely Yaba, Ikeja, Mushin and Oyingbo in Lagos, Nigeria were studied using standard microbiological methods. The objective of this study was to investigate the distribution of pathogenic bacteria recovered from RTE fruit salad in Lagos and assess bacteria load. The total aerobic and fecal coliform counts ranged from 1.50±0.5 x 10 5 cfu/g to 1.52±0.04 x 10 9 cfu/g and 5.0±0.5 x 10 4 cfu/g to 1.49±0.09x10 8 cfu/g respectively. The isolates were identified using morphological and biochemical tests. The results were analyzed using the one-way-ANOVA test. The test revealed that the average bacteria and coliform counts were not significantly different for the four markets, respectively. A further pairwise test also revealed that there was no significant difference between the markets. The predominant pathogenic bacteria associated with contamination of the RTE fruit salad were identified as E.coli (WO1); Klebisella sp (WO2); Proteus sp (WO3); Pseudomonas sp (WO4); Morganella morganni (WO5); Enterobacter sp (WO6); Staphylococcus aureus (coagulase +) (WO7) and Staphylococcus sp (coagulase-) (WO8). The presence of coliform and other bacteria in numbers exceeding the recommended microbiological standard is a reflection of unwholesome product, hence the need for proper microbiological safety analysis of fruit salad samples prepared for human consumption.

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