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Foundation Coursework in Undergraduate Inorganic Chemistry: Results from a National Survey of Inorganic Chemistry Faculty
No full textA national survey of inorganic chemists explored the self-reported topics covered in foundation-level courses in inorganic chemistry at the postsecondary level the American Chemical Society\u27s Committee on Professional Training defines a foundation course as one at the conclusion of which, a student should have mastered the vocabulary, concepts, and skills required to pursue in-depth study in that area. Anecdotal evidence suggested that more than one type of Inorganic Chemistry Foundation course was offered in the undergraduate chemistry curriculum. Cluster analysis confirmed this evidence, revealing four distinct foundation courses, each with unique profiles of topics covered. Faculty reported changes in content coverage over the past five years that mirror the evolving foci of inorganic chemistry research. These results potentially complicate how graduate programs evaluate incoming students\u27 understanding of inorganic chemistry and the design of national assessments of undergraduate inorganic chemistry courses
The Fiction About Past: History, Memory And Space-time In The Contemporary Oceanian Fiction
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(alpha,gamma) cross section measurements in the region of light p nuclei
No full textThe Zr-90(alpha,gamma) Mo-94, Zr-92(alpha,gamma) Mo-96, and Ge-74(alpha,gamma) Se-78 reaction cross sections were measured for the first time in an effort to expand the existing experimental database for (alpha,gamma) reactions relevant for the production of p nuclei in the universe. In particular, the Zr-90(alpha,gamma) Mo-94 reaction was identified by a sensitivity study for its potential impact on the gamma-process mass flow in the region of light p nuclei. The measurements were performed for energies E-alpha = 9.5-12.0 MeV at the University of Notre Dame using the SuN detector and the gamma-summing technique. The results are compared to theoretical calculations from the TALYS and NON-SMOKER nuclear reaction codes, and it is shown that the data greatly reduce the uncertainty in the cross section for the measured energies. The TALYS parameters that provide the best description of the experimental data are reported
Cautions About The Reliability Of Pairwise Gene Correlations Based On Expression Data
No full textBackground: Rapid growth in the availability of genome-wide transcript abundance levels through gene expression microarrays and RNAseq promises to provide deep biological insights into the complex, genome-wide transcriptional behavior of single-celled organisms. However, this promise has not yet been fully realized. Results: We find that computation of pairwise gene associations (correlation mutual information) across a set of 2782 total genome-wide expression samples from six diverse bacteria produces unexpectedly large variation in estimates of pairwise gene association regardless of the metric used, the organism under study, or the number and source of the samples. We pinpoint the cause to sampling bias. In particular, in repositories of expression data (e.g., Gene Expression Omnibus, GEO), many individual genes show small differences in absolute gene expression levels across the set of samples. We demonstrate that these small differences are due mainly to noise instead of signal attributable to environmental or genetic perturbations. We show that downstream analysis using gene expression levels of genes with small differences yields biased estimates of pairwise association. Conclusions: We propose flagging genes with small differences in absolute, RMA-normalized, expression levels (e.g., standard deviation less than 0.5), as potentially yielding biased pairwise association metrics. This strategy has the potential to substantially improve the confidence in genome-wide conclusions about transcriptional behavior in bacterial organisms. Further work is needed to further refine strategies to identify genes with small difference in expression levels prior to computing gene-gene association metrics
The Anchor, Volume 129.07: October 21, 2015
Get PDFThe Anchor began in 1887 and was first issued weekly in 1914. Covering national and campus news alike, Hope College’s student-run newspaper has grown over the years to encompass over two-dozen editors, reporters, and staff. For much of The Anchor\u27s history, the latest issue was distributed across campus each Wednesday throughout the academic school year (with few exceptions). In recent years The Anchor moved to monthly print issues and a more frequently updated website. The Anchor is now published in print twice per academic semester. Occasionally, the volume and/or issue numbering is irregular
The Anchor, Volume 128.21: April 8, 2015
Get PDFThe Anchor began in 1887 and was first issued weekly in 1914. Covering national and campus news alike, Hope College’s student-run newspaper has grown over the years to encompass over two-dozen editors, reporters, and staff. For much of The Anchor\u27s history, the latest issue was distributed across campus each Wednesday throughout the academic school year (with few exceptions). In recent years The Anchor moved to monthly print issues and a more frequently updated website. The Anchor is now published in print twice per academic semester. Occasionally, the volume and/or issue numbering is irregular
Building And Testing Correlations For The Estimation Of One-electron Reduction Potentials Of A Diverse Set Of Organic Molecules
Get PDFWe describe and evaluate a method for computationally predicting reduction potentials of a diverse group of organic molecules by linearly correlating calculated lowest unoccupied molecular orbital energies with ground state reduction potentials measured in acetonitrile. The approach is shown to provide a unique combination of extreme computational simplicity and excellent accuracy across a diverse range of organic structures and a wide window of reduction potentials. A disparate set of molecules (74 compounds belonging to six distinct structural families, comprised of molecules containing C, H, N, O, F, Cl, and Br, with functional groups including esters, ketones, halides, nitriles, quinones, alkenes, arenes, heteroarenes, and pyridinium and higher benzologs, all containing conjugated pi systems, spanning a 3.5-V range of reduction potentials) was used to build the correlations. This methodology was found to be computationally inexpensive compared with other approaches and to permit the useful prediction of reduction potentials of additional molecules of diverse structural types not included in the families used to determine the correlation parameters. The effects of varying the basis set used in the B3LYP electronic structure calculations and including solvent (compared with calculations in gas phase) were also examined. It was found that the inclusion of a continuum solvent model in the calculations was required for accurate results, particularly when including cationic species in the correlations (although when only neutral molecules were examined, reasonable results could even be obtained in vacuo). Several of the best correlations were used to predict the reduction potentials of seven much larger and structurally diverse chromophores that were not included in the correlation data set. Strong correlations (r2 values \u3e 0.99) with very good predictive abilities (root mean square deviation \u3c 60 mV) were found. This extremely simple and computationally efficient entirely closed-shell methodology is proven robust and useful for the design of new molecules capable of participating in redox processes, including electron transfer reactions. Copyright © 2015 John Wiley & Sons, Ltd