The aim of this study is to examine the relationships between chemistry laboratory anxiety, chemistry attitudes, and self-efficacy. Participants were 395 university students. Participants completed the Chemistry Laboratory Anxiety Scale, the Chemistry Attitudes Scale, and the Self-efficacy Scale. Results showed that chemistry laboratory anxiety was correlated negatively to chemistry attitudes and to self-efficacy. On the other hand, chemistry attitudes were found to be positively associated with self-efficacy. The path model showed that self-efficacy predicted chemistry laboratory anxiety in a negative way. Also, self-efficacy has a direct and positive effect on chemistry attitudes which in turn affects chemistry laboratory anxiety. Finally, chemistry laboratory anxiety was explained negatively by chemistry attitudes. Results were discussed in the light of literature.

Carbonic anhydrase inhibitors (CAIs) are a class of pharmaceuticals used as anti-glaucoma agents, diuretics and anti-epileptics. We report here the inhibitory capacities of benzenesulphonamides, cyclitols and phenolic compounds 1-11 against three human CA isozymes (hCA I, hCA II and hCA VI) and bovine skeletal muscle carbonic anhydrase III (bCA III). The four isozymes showed quite diverse inhibition profiles with K(i) values ranging from low micromolar to millimolar concentrations against all isoenzymes. Compound 5 and 6 had more powerful inhibitory action against hCA I and very similar action against hCA II and hCA VI as compared with acetazolamide (AZA) and sulphapyridine (SPD), specific CAIs. Probably the inhibition mechanism of the tested compounds is distinct of the sulphonamides with RSO(2)NH(2) groups and similar to that of the coumarins/lacosamide, i.e. binding to a distinct part of the active site than that where sulphonamides bind. These data may lead to drug design campaigns of effective CAIs possessing a diverse inhibition mechanism compared to other sulphonamide/sulphamate inhibitors.

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The present study deals with the production of citric acid from a ram horn peptone (RHP) by Aspergillus niger NRRL 330. A medium from RHP and a control medium (CM) were compared for citric acid production using A. niger in a batch culture. For this purpose, first, RHP was produced. Ram horns were hydrolyzed by treatment with acids (6 N H(2)SO(4), 6 N HCl) and neutralizing solutions. The amounts of protein, nitrogen, ash, some minerals, total sugars, total lipids and amino acids of the RHP were determined. RHP was compared with peptones with a bacto-tryptone from casein and other peptones. The results from RHP were similar to those of standard peptones. The optimal concentration of RHP for the production of citric acid was found to be 4% (w/w). A medium prepared from 4% RHP was termed ram horn peptone medium (RHPM). In comparison with CM, the content of citric acid in RHPM broth (84 g/l) over 6 days was 35% higher than that in CM broth (62 g/l). These results show that citric acid can be produced efficiently by A. niger from ram horn.

This study is aimed at comparing the success of programmed instruction with the conventional teaching approach on teaching stereochemistry, and whether gender has any effect on student success. Forty chemistry teacher trainees attending the same class in the Department of Chemistry Education in a large state university in eastern Turkey were the subjects of the study. Of the forty trainees twenty were selected as the experimental group and the other twenty as the control group. The study was implemented in a total of sixteen lecture hours (each 50 min) in four weeks (four lecture hours per week). The subject, stereochemistry in organic chemistry, was taught to the experimental group by the researcher through 'programmed instruction' and the control group was taught by the course lecturer through traditional teaching. The data collection tools were: Stereochemistry Achievement Test (SAT), programmed stages (frames), and the views of the students. An ANCOVA (Analysis of CoVariance) showed that there was a statistically significant difference between programmed instruction and conventional teaching approach on the success level of students' learning in stereochemistry. In addition, it was found that female students were more successful than their male counterparts in the experimental group. The findings suggest that programmed learning could be considered as a better alternative to conventional lecturing in teaching stereochemistry. [Chem. Educ. Res. Pract., 2006, 7 (1), 13-21]

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