305 research outputs found

    Achieving Specificity in Selected and Wild-Type N Peptide−RNA Complexes: The Importance of Discrimination against Noncognate RNA Targets

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    The boxB RNA pentaloops from the P22 and λ phages each adopt a GNRA tetraloop fold upon binding their cognate arginine-rich N peptides. The third loop base in P22 boxB (3-out) and the fourth in λ boxB (4-out) are excluded to accommodate this structure. Previously, we selected a pool of λ N sequences with random amino acids at loop contacting positions 13−22 for binding to either of these two GNRA-folded pentaloops or a canonical GNRA tetraloop and isolated a class of peptides with a new conserved arginine (R15). Here, we characterize the binding of λ N and these R15 peptides using fluorescent titrations with 2-aminopurine labeled versions of the three GNRA-folded loops and circular dichroism spectrometry. All peptides preferentially bind the λ boxB RNA loop. λ N and R15 peptide specificity against the P22 loop arises from the cost of rearranging its loop into the 4-out GNRA structure. Modeling indicates that the interaction of R8 with an additional loop phosphate in the 4-out GNRA pentaloop selectively stabilizes this complex relative to the tetraloop. R15 peptides gain additional discrimination against the tetraloop because their arginine also preferentially interacts with the 4-out GNRA pentaloop phosphate backbone, whereas K14 and W18 of λ N contribute equal affinity when binding the tetraloop. Nonspecific electrostatic interactions by basic residues near the C-termini of these peptides create significantly steeper salt dependencies in association constants for noncognate loops, aiding discrimination at high salt concentrations. Our results emphasize the importance of considering specificity against noncognate as well as nonspecific targets in the combinatorial and rational design of biopolymers capable of macromolecular recognition

    Achieving Specificity in Selected and Wild-Type N Peptide−RNA Complexes: The Importance of Discrimination against Noncognate RNA Targets

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    The boxB RNA pentaloops from the P22 and λ phages each adopt a GNRA tetraloop fold upon binding their cognate arginine-rich N peptides. The third loop base in P22 boxB (3-out) and the fourth in λ boxB (4-out) are excluded to accommodate this structure. Previously, we selected a pool of λ N sequences with random amino acids at loop contacting positions 13−22 for binding to either of these two GNRA-folded pentaloops or a canonical GNRA tetraloop and isolated a class of peptides with a new conserved arginine (R15). Here, we characterize the binding of λ N and these R15 peptides using fluorescent titrations with 2-aminopurine labeled versions of the three GNRA-folded loops and circular dichroism spectrometry. All peptides preferentially bind the λ boxB RNA loop. λ N and R15 peptide specificity against the P22 loop arises from the cost of rearranging its loop into the 4-out GNRA structure. Modeling indicates that the interaction of R8 with an additional loop phosphate in the 4-out GNRA pentaloop selectively stabilizes this complex relative to the tetraloop. R15 peptides gain additional discrimination against the tetraloop because their arginine also preferentially interacts with the 4-out GNRA pentaloop phosphate backbone, whereas K14 and W18 of λ N contribute equal affinity when binding the tetraloop. Nonspecific electrostatic interactions by basic residues near the C-termini of these peptides create significantly steeper salt dependencies in association constants for noncognate loops, aiding discrimination at high salt concentrations. Our results emphasize the importance of considering specificity against noncognate as well as nonspecific targets in the combinatorial and rational design of biopolymers capable of macromolecular recognition

    Conscientiousness in the Classroom: A Process Explanation

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    Although the research literature has established that Conscientiousness predicts task performance across a variety of achievement contexts (e.g., Barrick & Mount, 1991; OメConnor & Paunonen, 2007), comparatively less is known about the processes that underlie these relations. To the latter end, the current research examines effortful strategies and achievement goals as mediating factors that might explain why people with higher levels of Conscientiousness are predicted to reach higher levels of academic performance. In a longitudinal study, 347 college students completed measures of personality and achievement goals at the beginning of the class, followed by measures of effortful strategies multiple times throughout the semester. Results support the hypothesis that effortful strategies mediate the association between Conscientiousness and academic performance. Moreover, the statistical effects of Conscientiousness were generally independent of achievement goals, but a small portion of the effect was mediated through approach, not avoidance, achievement goals. These results highlight the importance of examining mediating processes between personality and outcomes, and in the case of Conscientiousness, our results suggest that effortful strategies might serve as a useful target for performance-enhancing interventions. Intelligence and hard work are often viewed as two essential ingredients for success in achievement contexts such as school and work. Consistent with this intuition, there is a well-established literature focusing on the connections between intelligence and performance (e.g., Judge, Higgins, Thoresen, & Barrick, 1999; Schmidt & Hunter, 1998), and a more recent history of research has pointed to the importance of Conscientiousness as a predictor of job performance that is relatively independent of intelligence (e.g., Barrick & Mount, 1991; Judge et al.,1999; Judge, Klinger, Simon, & Yang, 2008; Noftle & Robins, 2007; Roberts, Kuncel, Shiner, Caspi, & Goldberg, 2007). Turning to the academic context, a recent meta-analysis found that Conscientiousness, in fact, was the only practically significant personality predictor of postsecondary performance (OメConnor & Paunonen, 2007). Additional research is now required to understand why Conscientiousness predicts outcomes by identifying and modeling the mediating mechanisms between Conscientiousness and academic performance outcomes. In the current study, we propose that Conscientiousness is related to the types of goals, study strategies, and work habits that in turn promote success in academic contexts. We test this proposed process-based explanation using longitudinal data collected from college students. Our perspective is informed by McAdams and Pals's (2006) integrative personality framework, which identifies three major levels of personality. The first level, dispositional traits, is probably the most dominant approach in contemporary personality psychology. This level captures モbroad individual differences in behavior, thought, and feeling that account for general consistencies across situations and over timeヤ (p. 212). The second level, characteristic adaptations, incorporates social-cognitive variables such as goals that are モcontextualized in time, situations, and social rolesヤ (p. 212). The third and most fine-grained level addresses life narratives, or the construction of life stories and the development of individual identities. Our investigation focuses on the first two levels, in that we use constructs from the achievement goal literature to help explain how Conscientiousness (a dispositional or trait construct) is linked with academic outcomes. Formulating process models that bridge these two levels provides an opportunity to develop a more integrative understanding by moving beyond the study of simple trait-to-outcome correlations in the domains of personality and educational research

    An Efficient Ligation Method in the Making of an in vitro Virus for in vitro Protein Evolution

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    The “in vitro virus” is a molecular construct to perform evolutionary protein engineering. The “virion (=viral particle)” (mRNA-peptide fusion), is made by bonding a nascent protein with its coding mRNA via puromycin in a test tube for in vitro translation. In this work, the puromycin-linker was attached to mRNA using the Y-ligation, which was a method of two single-strands ligation at the end of a double-stranded stem to make a stem-loop structure. This reaction gave a yield of about 95%. We compared the Y-ligation with two other ligation reactions and showed that the Y-ligation gave the best productivity. An efficient amplification of the in vitro virus with this “viral genome” was demonstrated

    Energy's role in the extraversion (dis)advantage: How energy ties and task conflict help clarify the relationship between extraversion and proactive performance

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordWhile academic and practitioner literatures have proposed that extraverts are at an advantage in team‐based work, it remains unclear exactly what that advantage might be, how extraverts attain such an advantage, and under which conditions. Theory highlighting the importance of energy in the coordination of team efforts helps to answer these questions. We propose that extraverted individuals are able to develop more energizing relationships with their teammates and as a result are seen as proactively contributing to their team. However, problems in coordination (i.e., team task conflict) can reverse this extraversion advantage. We studied 27 project‐based teams at their formation, peak performance, and after disbandment. Results suggest that when team task conflict is low, extraverts energize their teammates and are viewed by others as proactively contributing to the team. However, when team task conflict is high, extraverts develop energizing relationships with fewer of their teammates and are not viewed as proactively contributing to the team. Our findings regarding energizing relationships and team task conflict clarify why extraversion is related to proactive performance and in what way, how, and when extraverts may be at a (dis)advantage in team‐based work

    The Maunakea Spectroscopic Explorer Book 2018

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    (Abridged) This is the Maunakea Spectroscopic Explorer 2018 book. It is intended as a concise reference guide to all aspects of the scientific and technical design of MSE, for the international astronomy and engineering communities, and related agencies. The current version is a status report of MSE's science goals and their practical implementation, following the System Conceptual Design Review, held in January 2018. MSE is a planned 10-m class, wide-field, optical and near-infrared facility, designed to enable transformative science, while filling a critical missing gap in the emerging international network of large-scale astronomical facilities. MSE is completely dedicated to multi-object spectroscopy of samples of between thousands and millions of astrophysical objects. It will lead the world in this arena, due to its unique design capabilities: it will boast a large (11.25 m) aperture and wide (1.52 sq. degree) field of view; it will have the capabilities to observe at a wide range of spectral resolutions, from R2500 to R40,000, with massive multiplexing (4332 spectra per exposure, with all spectral resolutions available at all times), and an on-target observing efficiency of more than 80%. MSE will unveil the composition and dynamics of the faint Universe and is designed to excel at precision studies of faint astrophysical phenomena. It will also provide critical follow-up for multi-wavelength imaging surveys, such as those of the Large Synoptic Survey Telescope, Gaia, Euclid, the Wide Field Infrared Survey Telescope, the Square Kilometre Array, and the Next Generation Very Large Array.Comment: 5 chapters, 160 pages, 107 figure

    Complex relationships among personality traits, job characteristics, and work behaviors

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    The aim of the study was to investigate the additive, mediating, and moderating effects of personality traits and job characteristics on work behaviors. Job applicants (N = 161) completed personality questionnaires measuring extraversion, neuroticism, achievement motivation, and experience seeking. One and a half years later, supervisors rated the applicants' job performance, and the job incumbents completed questionnaires about skill variety, autonomy, and feedback, work stress, job satisfaction, work self-efficacy, and propensity to leave. LISREL was used to test 15 hypotheses. Perceived feedback mediated the relationship between achievement motivation and job performance. Extraversion predicted work self-efficacy and job satisfaction. Work stress mediated the relationship between neuroticism and job satisfaction. Job satisfaction and experience seeking were related to propensity to leave. Autonomy, skill variety, and feedback were related to job satisfaction

    Conscientiousness, Career Success, and Longevity: A Lifespan Analysis

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    Markers of executive functioning, such as prudent planning for the future and impulse control, are related to conscientiousness and may be central to both occupational success and health outcomes. The aim of the study was to examine relations among conscientiousness, career success, and mortality risk across a 65-year period. Using data derived from 693 male participants in the Terman Life Cycle Study, we examined associations among childhood personality, midlife objective career success, and lifelong mortality risk through 2006. Conscientiousness and career success each predicted lower mortality risk (N = 693, relative hazard (rh) = 0.82 [95% confidence interval = 0.74, 0.91] and rh = 0.80 [0.71, 0.91], respectively), with both shared and unique variance. Importantly, childhood personality moderated the success–longevity link; conscientiousness was most relevant for least successful individuals. Conscientiousness and career success predicted longevity, but not in a straightforward manner. Findings highlight the importance of lifespan processes
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