Tweeting Facts,Facebooking Lives: The Influence of Language Use and Modality on Online Source Credibility

The present study examines how language use (e.g., personalized vs. depersonalized language) and modality (e.g., tweets vs. Facebook status updates) influence source credibility interdependently. A total of 257 participants read personalized or depersonalized health messages embedded in mock-up tweets or Facebook status updates. The results show that users perceive depersonalized tweets as more credible than depersonalized status updates posted on Facebook. On the other hand, personalized status updates on Facebook generate higher credibility judgments than personalized tweets. The findings are discussed in light of the MAIN model as well as the preconceived user expectations and communication norms of social media.     

What's in It for Me? Incentives,Learning, and Completion in Massive Open Online Courses

This study investigated the distribution of incentives (e.g., certificates, badges) for massive open online course (MOOC) completion, and relationships between incentives and MOOC outcomes. Participants were 779 MOOC students internationally who participated in at least 303 different MOOCs offered by at least 12 providers. MOOC participants most commonly intended to receive, and in actuality received, free and paid course certificates of completion; other incentives (e.g., digital badges, postsecondary credits) were far less common. In addition, MOOC participants' intentions to receive both free and paid certificates were consistently and positively related to perceived learning and course completion, net other factors. (Keywords: massive open online courses, MOOCs, motivation, incentives, microcredentials, certificates of completion)     

A comparison between two different automated total 25-hydroxyvitamin D immunoassay methods using liquid chromatography-tandem mass spectrometry

Introduction

Total 25-hydroxyvitamin D [25(OH)D] is the most reliable indicator of vitamin D status. In this study, we compared two automated immunoassay methods, the Abbott Architect 25-OH Vitamin D assay and the Roche Cobas Vitamin D total assay, with the liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Materials and methods

One hundred venous blood samples were randomly selected from routine vitamin D tests. Two of the serum aliquots were analyzed at the Abbott Architect i2000 and the Roche Cobas 6000’s module e601 in our laboratory within the same day. The other serum aliquots were analyzed at the LC-MS/MS in different laboratory. Passing-Bablok regression analysis and Bland-Altman plot were used to compare methods. Inter-rater agreement was analyzed using kappa (κ) analysis.

Results

The Roche assay showed acceptable agreement with the LC-MS/MS based on Passing-Bablok analysis (intercept: -5.23 nmol/L, 95% CI: -8.73 to 0.19; slope: 0.97, 95% CI: 0.77 to 1.15). The Abbott assay showed proportional (slope: 0.77, 95% CI: 0.67 to 0.85) and constant differences (intercept: 17.08 nmol/L; 95% CI: 12.98 to 21.39). A mean bias of 15.1% was observed for the Abbott and a mean bias of -14.1% was observed for the Roche based on the Bland-Altman plots. We found strong to nearly perfect agreement in vitamin D status between the immunoassays and LC-MS/MS. (κ: 0.83 for Abbott, κ: 0.93 for Roche) using kappa analysis.

Conclusion

Both immunoassays demonstrated acceptable performance, but the Roche Cobas assay demonstrated better performance than the Abbott Architect in the studied samples.Key words: 25-Hydroxyvitamin D, chromatography, immunoassay, methods, tandem mass spectrometry     

Middle School Science Teachers’ Discursive Purposes and Talk Moves in Supporting Students’ Experiments

Science & Education - The paper reports qualitative findings from a study about how science teachers enacted discursive purposes and talk moves to support the students’ experiments....     

Characterization of two-dimensional cellular automata over ternary fields

The set of papers [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999) deals with the behavior of the uniform two-dimensional cellular automata over binary fields (Z₂). Some structural properties and precise mathematical models using matrix algebra over the field Z₂ are reported for characterizing the behavior of two-dimensional nearest neighborhood linear cellular automata with null and periodic boundary conditions [3], [4], [6] and [7] (Chattopadhyay et al., 1999; Dihidar and Choudhury, 2004; Khan et al., 1997, 1999). In this paper, we characterize two-dimensional linear cellular automata transformations by using matrix algebra built on Z₃. We analyze some results for two-dimensional CA with rule numbers 2460N and 2460P. Finally, we investigate the dimension of the kernel of two-dimensional cellular automata defined by the rule number 2460N.     

The process of supervision in the turkish educational system: purpose, structure, operation

The aim of this study is to provide information on the purposes, structure and operation of the process of supervision in the Turkish educational system. In this paper, the historical development of supervision services in the Turkish educational system, as well as the purposes and principles of educational supervision in Turkey and the structure of supervision in the Turkish educational system are defined. Moreover, the organization of sub-systems of the Ministry of National Education and that of supervision at elementary schools, hiring supervisors, their training, duties and responsibilities as well as working principles are presented. In addition, a detailed analysis of the supervision of institutions and teachers by supervisors is included.