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This paper reports on the use of continuous assessment in a statistics course for social scientists, in which assignments are open‐ended and use real data. The students' performance in the assignments and a formal examination are compared, and it is found that when students are assessed by a combination of continuous assessment and examination, those students who carry out the majority of the assignments score higher examination marks than do the rest.  相似文献   
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A systematic comparison between the grafting‐to (convergent) and grafting‐from (divergent) synthetic routes leading to cyclic peptide–polymer conjugates is described. The reversible addition–fragmentation chain transfer (RAFT) process was used to control the polymerizations and the couplings between cyclic peptide and polymer or RAFT agent were performed using N‐hydroxysuccinimide (NHS) active ester ligation. The kinetics of polymerization and polymer conjugation to cyclic peptides were studied for both grafting‐to and grafting‐from synthetic routes, using N‐acryloyl morpholine as a model monomer. The cyclic peptide chain transfer agent was able to mediate polymerization as efficiently as a traditional RAFT agent, reaching high conversion in the same time scale while maintaining excellent control over the molecular weight distribution. The conjugation of polymers to cyclic peptides proceeded to high conversion, and the nature of the carbon at the α‐position to the NHS group was found to play a crucial role in the reaction kinetics. The study was extended to a wider range of monomers, including hydrophilic and temperature responsive acrylamides, hydrophilic and hydrophobic acrylates, and hydrophobic and pH responsive methacrylates. Both approaches lead to similar peptide–polymer conjugates in most cases, while some exceptions highlight the advantages of one or the other method, thereby demonstrating their complementarity. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1003–1011  相似文献   
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Apparently solvent-mediated and not through-bond photoinduced electron transfer (ET) takes place from the porphyrin (P) unit to the methylviologen (MV2+) unit in the rigid U-shaped molecules 1 (i.e., kTSET>kTBET; TS=through-solvent, TB=through-bond). The ratio of the rates of charge separation to charge recombination is greater than 1400:1.  相似文献   
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