This study investigated within and cross-language effects of morphological awareness on word reading among Spanish-speaking children who were English Language Learners. Participants were 97 Spanish-speaking children in grade 4 and grade 7. Morphological awareness in Spanish and in English was evaluated with two measures of derivational morphology. The results showed that Spanish morphological awareness contributed unique variance to Spanish word reading after controlling for other reading related variables. English morphological awareness also explained unique variance in English word reading. Cross-linguistic transfer of morphological awareness was observed from Spanish to English, but not from English to Spanish. These results suggest that morphological awareness is important for word reading in Spanish, a shallow orthography with a complex morphological system. They also suggest that morphological awareness developed in children's L1 is associated with word reading in English, their L2.

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This study examined compound awareness in relation to Chinese children's vocabulary acquisition and character reading. Two aspects of compound awareness were investigated: the ability to identify the head of a compound noun and the ability to construct a new compound word from familiar morphemes. The compound awareness tasks, along with rapid automatized naming (RAN) and phonological awareness tasks, were administered to 29 first graders and 30 second graders in Mainland China. Results show that (1) compound awareness develops relatively early among Chinese children and improves with age, (2) compound awareness explains unique variance in vocabulary and character reading, after controlling for age, RAN, and phonological awareness, and (3) the contribution made by compound awareness to vocabulary is much larger than the contribution made by phonological awareness. These results demonstrate that compound awareness plays a central role in Chinese children's literacy development, particularly in vocabulary acquisition.

The absolute pK a values of 24 representative amine compounds, including cocaine, nicotine, 10 neurotransmitters, and 12 anilines, in aqueous solution were calculated by performing first-principles electronic structure calculations that account for the solvent effects using four different solvation models, i.e. the surface and volume polarization for electrostatic interaction (SVPE) model, the standard polarizable continuum model (PCM), the integral equation formalism for the polarizable continuum model (IEFPCM), and the conductor-like screening solvation model (COSMO). Within the examined computational methods, the calculations using the SVPE model lead to the absolute pK a values with the smallest root-mean-square-deviation (RMSD) value (1.18). When the SVPE model was replaced by the PCM, IEFPCM, and COSMO, the RMSD value of the calculated absolute pK a values became 3.21, 2.72, and 3.08, respectively. All types of calculated pK a values linearly correlate with the experimental pK a values very well. With the empirical corrections using the linear correlation relationships, the theoretical pK a values are much closer to the corresponding experimental data and the RMSD values become 0.51 to 0.83. The smallest RMSD value (0.51) is also associated with the SVPE model. All of the results suggest that the first-principles electronic structure calculations using the SVPE model are a reliable approach to the pK a prediction for the amine compounds.

Catalytic mechanism for butyrylcholineserase (BChE)-catalyzed hydrolysis of acetylcholine (ACh) has been studied by performing pseudobond first-principles quantum mechanical/molecular mechanical-free energy (QM/MM-FE) calculations on both acylation and deacylation of BChE. It has been shown that the acylation with ACh includes two reaction steps including the nucleophilic attack on the carbonyl carbon of ACh and the dissociation of choline ester. The deacylation stage includes nucleophilic attack of a water molecule on the carboxyl carbon of substrate and dissociation between the carboxyl carbon of substrate and hydroxyl oxygen of Ser198 side chain. Notably, despite of the fact that acetylcholinesterase (AChE) and BChE are very similar enzymes, the acylation of BChE with ACh is rate-determining, which is remarkably different from AChE-catalyzed hydrolysis of ACh in which the deacylation is rate-determining. The computational prediction is consistent with available experimental kinetic data. The overall free energy barrier calculated for BChE-catalyzed hydrolysis of ACh is 13.8 kcal/mol, which is in good agreement with experimentally-derived activation free energy of 13.3 kcal/mol.

In this study, we aimed to examine mathematics teachers' daily lesson plans and associated practices and thinking in lesson plan development. By focusing on teachers' preparation for teaching fraction division, we collected and analyzed a sequence of four lesson plans from each of six mathematics teachers in six different elementary schools in China. Interviews with these teachers were also analyzed to support the lesson plan analysis and reveal teachers' thinking behind their practices. The results show that Chinese teachers placed a great consideration on several aspects of lesson planning, including content, process, and their students' learning. Teachers' lesson plans were similar in terms of some broad features, but differed in details and specific approaches used. While the textbook's influence was clearly evident in these teachers' lesson plans, lesson planning itself was an important process for Chinese teachers to transform textbook content into a script unique to different teachers and their students. Implications obtained from Chinese teachers' lesson planning practices and their thinking are then discussed in a broad context.

We have performed a series of first-principles electronic structure calculations to study competing reaction pathways and the corresponding free-energy barriers for the ester hydrolysis of intracellular second-messenger adenosine 3′,5′-cyclic monophosphate (cAMP) and related phosphodiesters including trimethylene phosphate (TMP). Reaction coordinate calculations show three fundamental reaction pathways for the ester hydrolysis, including (A) attack of a hydroxide ion at the P atom of the phosphate anion (an S N 2 process without a pentacoordinated phosphorus intermediate), (B) direct attack of a water molecule at the P atom of the anion (a three-step process), and (C) direct attack of a water molecule at the P atom of the neutral ester molecule (a two-step process). The calculated energy results show that for the reactions in the gas phase the freeenergy barrier for pathway A is the highest and the barrier for the rate-controlling step of pathway C is the lowest. However, for the reactions in aqueous solution, the free-energy barrier calculated for pathway A becomes the lowest, and the two main hydrolysis pathways are A and B. We also have demonstrated how the pK a of the ester and the pH of the reaction solution affect the relative contributions of different hydrolysis pathways to the total hydrolysis rate. Reaction pathway A should be dominant for the cAMP hydrolysis in neutral aqueous solution. However, the relative contribution of pathway A to the total hydrolysis rate should decrease with decreasing pH of the solution. For pH < ∼3.7, the contribution of pathway B is larger. For pH > ∼3.7, the contribution of pathway A is larger. The reliability of our theoretical predictions is supported by the excellent agreement of the calculated free-energy barrier with available experimental data for the hydrolysis of TMP in solution.

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