We examined the effect of the perceived classroom environment on math self-efficacy and the effect of math self-efficacy on standardized math test performance. Upper elementary school students (n = 1163) provided self-reports of their perceived math selfefficacy and the degree to which their math classroom environment was masteryoriented, challenging, and caring. Individual student scores on the California Standards Test for Mathematics were also collected. A series of two-level models revealed that students who perceived their classroom environments as more caring, challenging, and mastery-oriented had significantly higher levels of math efficacy, and higher levels of math efficacy positively predicted math performance. Analysis of the indirect effects of classroom variables on math performance indicated a small significant mediating effect of self-efficacy. Implications for research on self-efficacy and the perceived classroom environment are discussed.Math Self-efficacy 3 Does Math Self-efficacy Mediate the Effect of the Perceived Classroom Environment on Standardized Math Test Performance?In the current high-stakes testing environment, any attribute of a student that positively influences achievement is of interest. The degree to which a student believes that he/she is capable of performing specific tasks, referred to as self-efficacy, is particularly relevant given that self-efficacy has been argued to have powerful effects on achievement behavior (Bandura, 1986). Those with higher self-efficacy are proposed to have higher aspirations, stronger commitments to their goals, and recover more quickly from setbacks than those lower in self-efficacy. Beliefs in one's efficacy can vary across academic subjects (e.g. reading vs. writing) and self-efficacy for mathematics has received close attention. Students with higher math self-efficacy persist longer on difficult math problems and are more accurate in math computations than those lower in math self-efficacy (Collins, 1982; Hoffman & Schraw, 2009). Math self-efficacy is also a stronger predictor of math performance than either math anxiety or previous math experience ( Pajares & Miller, 1994; Pajares & Miller, 1995, respectively) and influences math performance as strongly as overall mental ability (Pajares & Kranzler, 1995).The demonstrated importance of self-efficacy in academic achievement has provoked widespread interest in specific factors that affect a student's self-efficacy beliefs. Bandura's (1997) social-cognitive theory proposed that self-efficacy is most strongly affected by one's previous performance and research largely supports this (Chen & Zimmerman, 2007). His theory also suggests that self-efficacy is affected by observing others (e.g. watching peers succeed at a task), verbal persuasion (e.g. encouragement from parents and teachers), and interpretation of physiological states (e.g. Math Self-efficacy 4 lack of anxiety may be a signal that one possesses skills). Although several studies indicate that manipulating features of learning...

The compounds synthesized in this research were designed with the goal of establishing a new paradigm for mixed-base-pair DNA sequence-specific recognition. The design scheme starts with a cell-permeable heterocyclic cation that binds to AT base pair sites in the DNA minor groove. Modifications were introduced in the original compound to include an H-bond accepting group to specifically recognize the G-NH that projects into the minor groove. Therefore, a series of heterocyclic cations substituted with an azabenzimidazole ring has been designed and synthesized for mixed-base-pair DNA recognition. The most successful compound, 12a, had an azabenzimidazole to recognize G and additional modifications for general minor groove interactions. It binds to the DNA site −AAAGTTT– more strongly than the −AAATTT– site without GC and indicates the design success. Structural modifications of 12a generally weakened binding. The interactions of the new compound with a variety of DNA sequences with and without GC base pairs were evaluated by thermal melting analysis, circular dichroism, fluorescence emission spectroscopy, surface plasmon resonance, and molecular modeling.

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Structural results with minor groove binding agents, such as netropsin, have provided detailed, atomic level views of DNA molecular recognition. Solution studies, however, indicate that there is complexity in the binding of minor groove agents to a single site. Netropsin, for example, has two DNA binding enthalpies in isothermal titration calorimetry (ITC) experiments that indicate the compound simultaneously forms two thermodynamically different complexes at a single AATT site. Two proposals for the origin of this unusual observation have been developed: (i) two different bound species of netropsin at single binding sites and (ii) a netropsin induced DNA hairpin to duplex transition. To develop a better understanding of DNA recognition complexity, the two proposals have been tested with several DNAs and the methods of mass spectrometry (MS), polyacrylamide gel electrophoresis (PAGE) and nuclear magnetic resonance spectroscopy in addition to ITC. All of the methods with all of the DNAs investigated clearly shows that netropsin forms two different complexes at AATT sites, and that the proposal for an induced hairpin to duplex transition in this system is incorrect.