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    Our plenary speaker this morning was Thomas Holme, of Iowa State University, speaking to us about the standardized assessments in chemistry.  Sounds boring, but he raised some interesting and insightful thoughts about assessment.

    He started out by describing the fine line he has to walk as an instructor:

    “Teaching is inherently personal and inescapably corporate.  The corporate interests are largely articulated in terms of assessment.”

    “Assessment” has typically been equated with “accountability,” he pointed out, making it somewhat unppuar as a topic.  This is unfortunate, since assessments are so useful on many levels.

    The American Chemical Society (ACS) develops validated exams for use in courses every year, which I found astounding.  Back in 1921 the Division of Chemical Education decided to construct objective tests for use by the education community.  These exams are written by committee, which over a course of meetings set the content coverage, write the items, edit the items, do trial testing in classes, look at the item stats, and then set the exams.

    They’ve written a variety of instruments, the full-year chemistry exam, first and second term exams, conceptual exams, and brief exams.  A new exam is added every year.  There is a bit of an issue with publishing average, however; they invite users to send them their course averages.  However, there is a strong self-selection effect, since teachers often don’t send in poor scores.  When they published their pilot test averages, they found that there was a “Lake Woebegone” effect – nobody would send them scores that were below that average.  However, the averages are helpful for instructors because they can use that to set the grade point average for the exam.  (Unfortunately, I missed their solution to this problem).

    The process seems quite well thought-out, including content validity, psychometrics,  etc etc.   Good stuff.  And more, of course, than we could expect an individual instructor to do.  This is a grassroots process, he says – ACS isn’t telling anybody how to teach.  They hope the exams will be used in 15-20% of classes.  Hundreds of volunteers put in time to write the exams.  Interestingly, the ACS doesn’t actually fund the test — they make their money from actually selling the test for use by instructors.

    “I’m simultaneously jealous that ACS is doing this,” commented Noah Finkelstein, “and happy that APS isn’t doing it because then I’d have to do it.”

    Still, we’ve noticed in PER that instructors aren’t using research-based assessments, and typically rely on exams and HW to identify whether their instruction is working.  If they’re not using instruments like the FCI, I wonder if we could develop such research-based assessments to provide instructors  meaningful feedback on student performance, that is also valued by the administration?  But how would we avoid the K12 dilemma of “teaching to the test” and assessing instructors overly on student performance?

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    The inexpensive tests that look for hidden blood in a person’s stool are effective for colon cancer screening, a study out Tuesday confirms. The findings, reported in the Canadian Medical Association Journal, give some extra weight to fecal occult blood testing (FOBT) as a valid option for early detection of colon cancer. Experts generally recommend that people at average risk of colon cancer start screening tests for the disease at age 50. And they can pick from a number of tests that have all been found to cut the risk of dying from colon cancer.
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    P Aggarwal, S SaxenaIndian Journal of Cancer 2011 48(2):211-215Objectives: The present study was undertaken to detect and compare the pattern of collagen fibers in odontogenic cysts and also to find out if this methodology could be used to predict the aggressive nature of odontogenic cysts by comparing with the odontogenic tumors. Materials and Methods: The collagen in the wall of 11 odontogenic keratocysts, 14 dentigerous cysts and 14 radicular cysts was studied histochemically by staining sections with picrosirius red and examining under polarizing microscope. This was compared to 10 cases of odontogenic tumors using Z test of proportion at 1% and 5%. Results: In dentigerous cysts, odontogenic keratocysts and odontogenic tumors, the predominant color of collagen fibers birefringence was found to be orangish red, whereas in radicular cysts the collagen fiber was of green color. Conclusions: Similar birefringence pattern of collagen fibers between dentigerous cysts, odontogenic keratocysts and odontogenic tumors may indicate that these lesions have a common histogenesis with a broad spectrum of biological behavior and belong to the same group, i.e., are developmental in origin. Different patterns of radicular cysts suggest different biological behavior and a positive role of inflammation on polarization color of collagen fibers.
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    P Singh, JD Wig, R Srinivasan, BD RadotraIndian Journal of Cancer 2011 48(2):170-174Background: Smad4, Smad6 and Smad7 are important molecules in TGF-beta pathway, which plays an important role in pancreatic ductal adenocarcinoma (PDAC) biology. Aims : This study examined the expression profiles of Smad4, Smad6 and Smad7 mRNA in patient samples of PDAC and their relationship to Smad protein expression, SMAD4 gene mutations, clinicopathological parameters and patient survival. Settings and Design: Surgically resected, paired normal and tumor tissues of 25 patients of PDAC were studied. Materials and Methods: Protein and mRNA levels were assessed by immunohistochemistry and RT-PCR, respectively. Statistical Methods: Statistical analysis was done using Student's t-test, Pearson's chi-square test, Spearman's Rank Correlation, Pearson's Correlation test and Kaplan-Meier Logrank test. Results: While there was a highly significant difference in the protein levels of all three Smads in tumor as compared to normal samples, mRNA levels were significantly different only for Smad4. Protein levels did not correlate significantly with mRNA levels for any of the three Smads. The mRNA levels of Smad4 and Smad6, Smad4 and Smad7, and Smad6 and Smad7 in tumor samples showed a significant positive correlation. The relationship of Smad4 mRNA expression to SMAD4 gene status and Smad4 protein expression was discordant and there was no significant correlation between mRNA expression and clinicopathological parameters and patient survival. Conclusion : The absence of concordance between SMAD4 gene status, mRNA expression and Smad4 protein expression suggests the presence of other regulatory mechanisms in Smad4 transcription and translation in PDAC.
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    Test your 3rd grade general science knowledge with this fun multiple choice quiz. chemistry.about.com


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