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In principle, molecularly imprinted polymer science and technology provides a means for ready access to nano-structured polymeric materials of predetermined selectivity. The versatility of the technique has brought it to the attention of many working with the development of nanomaterials with biological or biomimetic properties for use as therapeutics or in medical devices. Nonetheless, the further evolution of the field necessitates the development of robust predictive tools capable of handling the complexity of molecular imprinting systems. The rapid growth in computer power and software over the past decade has opened new possibilities for simulating aspects of the complex molecular imprinting process. We present here a survey of the current status of the use of in silico-based approaches to aspects of molecular imprinting. Finally, we highlight areas where ongoing and future efforts should yield information critical to our understanding of the underlying mechanisms sufficient to permit the rational design of molecularly imprinted polymers.

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Visual representations are essential for communication and meaning‐making in chemistry, and thus the representational practices play a vital role in the teaching and learning of chemistry. One powerful contemporary model of classroom learning, the variation theory of learning, posits that the way an object of learning gets handled is another vital feature for the establishment of successful teaching practices. An important part of what lies behind the constitution of teaching practices is visual representational reasoning that is a function of disciplinary relevant aspects and educationally critical features of the aspects embedded in the intended object of learning. Little is known about teachers reasoning about such visual representational practices. This work addresses this shortfall in the area of chemical bonding. The data consist of semistructured interviews with 12 chemistry teachers in the Swedish upper secondary school system. The methodology uses a thematic analytic approach to capture and characterize the teachers’ reasoning about their classroom visual representational practices. The results suggest that the teachers’ reasoning tended to be limited. However, the teachers’ pay attention to the meaning‐making potential of the approaches for showing representations. The analysis presents these visualization approaches and the discussion makes theoretical links to the variation theory of learning.

The enantioselective reduction of 2-pentanone to (R)- and (S)-2-pentanol by Thermoanaerobacter (formerly Thermoanaerobium) brockii alcohol dehydrogenase (TBADH) in mixtures of water and water-miscible organic solvents was investigated. Significant enzymatic activity was retained in up to 87% methanol, ethanol and acetonitrile. The changes in enzyme activity as a function of organic solvent were correlated to structural alterations of TBADH with a series of spectroscopic studies (fluorescence, fluorescence quenching and circular dichroism (CD)). Interestingly, this study shows that the tetrameric form of TBADH is not critical for catalytic performance.

Since visual representations play a particularly important role in the teaching and learning of chemistry, the exploration described in this article focuses on them. This is an explorative study of the qualitatively different ways that visual representations can be unpacked by Swedish upper secondary school chemistry teachers dealing with intermolecular forces. Unpacking is characterized as the ways that visual representations get used to open up the possibility of having the critical aspects and features of an intended object of learning being brought into focal awareness, initially on their own and then simultaneously.The analysis, which combines a phenomenographic and a social semiotic approach, leads to the characterizations of five qualitatively different ways that visual representations may be unpacked. These outcome categories are presented in terms of a conceptual hierarchy, where two of these ways of unpacking are characterized as being teachercentered and the other three as student-centered. This leads to a case being made that if teachers use studentcentered ways of unpacking visual representations, then their students will be more likely to gain greater access to critical aspects and features of the enacted object of learning. We argue that in terms of making theoretical and This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

The inducible Mar phenotype of Escherichia coli is associated with increased tolerance to multiple hydrophobic antibiotics as well as some highly hydrophobic organic solvents such as cyclohexane, mediated mainly through the AcrAB/TolC efflux system. The influence of water miscible alcohols ethanol and 1-propanol on a Mar constitutive mutant and a mar deletion mutant of E. coli K-12, as well as the corresponding strains carrying the additional acrAB deletion, was investigated. In contrast to hydrophobic solvents, all strains were killed in exponential phase by 1-propanol and ethanol at rates comparable to the parent strain. Thus, the Mar phenotype does not protect E. coli from killing by these more polar solvents. Surprisingly, AcrAB does not contribute to an increased alcohol tolerance. In addition, sodium salicylate, at concentrations known to induce the mar operon, was unable to increase 1-propanol or ethanol tolerance. Rather, the toxicity of both solvents was increased in the presence of sodium salicylate. Collectively, the results imply that the resilience of E. coli to water miscible alcohols, in contrast to more hydrophobic solvents, does not depend upon the AcrAB/TolC efflux system, and suggests a lower limit for substrate molecular size and functionality. Implications for the application of microbiological systems in environments containing high contents of water miscible organic solvents, e.g., phage display screening, are discussed.