Assessing evaluative measures for Internet-based courseware

Although there is a consensus in th~ literature on the many uses of the Internet in education, as well as the unique features of the Internet for presenting facts and information, there is no consensus on a standardized method for evaluating Internetbased courseware. Educators rarely have the opportunity to participate in the development of Internet-based courseware, yet they are encouraged to use the technology in their learning environments. This creates a need for summative evaluation methods for Internet-based health courseware. The purpose ofthis study was to assess evaluative measures for Internet-based courseware. Specifically, two entities were evaluated within the study: a) the outcome of the Internet-based courseware, and b) the Internet-based courseware itself. To this end, the Web site www.bodymatters.com was evaluated using two different approaches by two different cohorts. The first approach was a performance appraisal by a group of endusers. A positive, statistically significant change in the students performance was observed due to the intervention ofthe Web site. The second approach was a productoriented evaluation ofthe Web site with the use of a criterion-based checklist and an open-ended comments section. The findings indicate that a summative, criterion-based evaluation is best completed by a multidisciplinary team. The findi~gs also indicated that the two different cohorts reported different product-oriented appraisals of the Web site. The current research confirmed previous research that found that experts returning a poor evaluation of a Web site did not have a relationship to whether or not the end-users performance improved due to the intervention of the Web site.

The versatility and utilization of phosphorus based compounds in classic carbon-carbon bond forming and esterification reactions

The phosphonium salt room temperature ionic liquid tetradecyltrihexylphosphonium chloride (THPC) has been employed as an efficient reusable media for the palladium catalyzed Suzuki cross-coupling reaction of aryl halides, including aryl chlorides, under mild conditions. The cross-coupling reactions were found to proceed in THPC containing small amounts ofwater and toluene (single phase) using potassium phosphate and 1% Pd2(dba)3'CHCI3. Variously substituted iodobenzenes, including electron rich derivatives, reacted efficiently in THPC with a variety of arylboronic acids and were all complete within 1 hour at 50°C. The corresponding aryl bromides also reacted under these conditions with the addition of a catalytic amount of triphenylphosphine that allowed for complete conversion and high isolated yields. The reactions involving aryl chlorides were considerably slower, although the addition of triphenylphosphine and heating at 70°C allowed high conversion of electron deficient derivatives. Addition of water and hexane to the reaction products results in a triphasic system, from which the catalyst was then recycled by removing the top (hexanes) and bottom (aqueous) layers and adding the reagents to the ionic liquid which was heated again at 50°C; resulting in complete turnover of iodobenzene. Repetition of this procedure gave the biphenyl product in 82-97% yield (repeated five times) for both the initial and recycled reaction sequences. IL ESTERIFICATIONREACTION A new class oftrialkylphosphorane has been prepared through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence oftriethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a subtle interplay involving basicity of the reaction media, solvent, and tuning the electronic and steric nature of the carboxylic acid and stenc nature of the phosphorane employed. A coherent mechanism is postulated to explain these observations involving reaction via an initial acyloxyphosphonium ion.