12 research outputs found
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Registered replication report: a large multilab cross-cultural conceptual replication of Turri, Buckwalter, & Blouw (2015)
According to the Justified True Belief account of knowledge (JTB), a person can only truly know something if they have a belief that is both justified and true (i.e., knowledge is justified true belief). This account was challenged by Gettier (1963), who argued that JTB does not explain knowledge attributions in certain situations, later called Gettier-type cases, wherein a protagonist is justified in believing something to be true, but their belief was only correct due to luck. Lay people may not attribute knowledge to protagonists with justified but only luckily true beliefs. While some research has found evidence for these so-called Gettier intuitions (e.g., Machery et al., 2017a), Turri et al. (2015) found no evidence that participants attributed knowledge in a counterfeit-object Gettier-type case differently than in a matched case of justified true belief. In a large-scale, cross-cultural conceptual replication of Turri and colleaguesâ (2015) Experiment 1 (N = 4,724) using a within-participants design and three vignettes across 19 geopolitical regions, we did find evidence for Gettier intuitions; participants were 1.86 times more likely to attribute knowledge to protagonists in standard cases of justified true belief than to protagonists in Gettier-type cases. These results suggest that Gettier intuitions may be detectable across different scenarios and cultural contexts. However, the size of the Gettier intuition effect did vary by vignette, and the Turri et al. (2015) vignette produced the smallest effect, which was similar in size to that observed in the original study. Differences across vignettes suggest epistemic intuitions may also depend on contextual factors unrelated to the criteria of knowledge, such as the characteristics of the protagonist being evaluated
NanoLuc Complementation Reporter Optimized for Accurate Measurement of Protein Interactions in Cells
Protein-fragment
complementation assays (PCAs) are widely used
for investigating protein interactions. However, the fragments used
are structurally compromised and have not been optimized nor thoroughly
characterized for accurately assessing these interactions. We took
advantage of the small size and bright luminescence of NanoLuc to
engineer a new complementation reporter (NanoBiT). By design, the
NanoBiT subunits (i.e., 1.3 kDa peptide, 18 kDa polypeptide) weakly
associate so that their assembly into a luminescent complex is dictated
by the interaction characteristics of the target proteins onto which
they are appended. To ascertain their general suitability for measuring
interaction affinities and kinetics, we determined that their intrinsic
affinity (<i>K</i><sub>D</sub> = 190 ÎŒM) and association
constants (<i>k</i><sub>on</sub> = 500 M<sup>â1</sup> s<sup>â1</sup>, <i>k</i><sub>off</sub> = 0.2 s<sup>â1</sup>) are outside of the ranges typical for protein interactions.
The accuracy of NanoBiT was verified under defined biochemical conditions
using the previously characterized interaction between SME-1 ÎČ-lactamase
and a set of inhibitor binding proteins. In cells, NanoBiT fusions
to FRB/FKBP produced luminescence consistent with the linear characteristics
of NanoLuc. Response dynamics, evaluated using both protein kinase
A and ÎČ-arrestin-2, were rapid, reversible, and robust to temperature
(21â37 °C). Finally, NanoBiT provided a means to measure
pharmacology of kinase inhibitors known to induce the interaction
between BRAF and CRAF. Our results demonstrate that the intrinsic
properties of NanoBiT allow accurate representation of protein interactions
and that the reporter responds reliably and dynamically in cells
Raising the value of research studies in psychological science by increasing the credibility of research reports: the transparent Psi Project
The low reproducibility rate in social sciences has produced hesitation among researchers in accepting published findings at their face value. Despite the advent of initiatives to increase transparency in research reporting, the field is still lacking tools to verify the credibility of research reports. In the present paper, we describe methodologies that let researchers craft highly credible research and allow their peers to verify this credibility. We demonstrate the application of these methods in a multi-lab replication of Bemâs Experiment 1 (2011) on extrasensory perception (ESP), which was co-designed by a consensus panel including both proponents and opponents of Bemâs original hypothesis. In the study we applied direct data deposition in combination with born-open data and real-time research reports to extend transparency to protocol delivery and data collection. We also used piloting, checklists, laboratory logs and video documented trial sessions to ascertain as-intended protocol delivery, and external research auditors to monitor research integrity. We found 49.89% successful guesses, while Bem reported 53.07% success rate, with the chance level being 50%. Thus, Bemâs findings were not replicated in our study. In the paper we discuss the implementation, feasibility, and perceived usefulness of the credibility-enhancing methodologies used throughout the project
Correction to: âRaising the value of research studies in psychological science by increasing the credibility of research reports: The Transparent Psi Projectâ (2023) by Kekecs et al.
Engineered Luciferase Reporter from a Deep Sea Shrimp Utilizing a Novel Imidazopyrazinone Substrate
Bioluminescence methodologies have been extraordinarily
useful
due to their high sensitivity, broad dynamic range, and operational
simplicity. These capabilities have been realized largely through
incremental adaptations of native enzymes and substrates, originating
from luminous organisms of diverse evolutionary lineages. We engineered
both an enzyme and substrate in combination to create a novel bioluminescence
system capable of more efficient light emission with superior biochemical
and physical characteristics. Using a small luciferase subunit (19
kDa) from the deep sea shrimp <i>Oplophorus gracilirostris</i>, we have improved luminescence expression in mammalian cells âŒ2.5
million-fold by merging optimization of protein structure with development
of a novel imidazopyrazinone substrate (furimazine). The new luciferase,
NanoLuc, produces glow-type luminescence (signal half-life >2 h)
with
a specific activity âŒ150-fold greater than that of either firefly
(<i>Photinus pyralis</i>) or <i>Renilla</i> luciferases
similarly configured for glow-type assays. In mammalian cells, NanoLuc
shows no evidence of post-translational modifications or subcellular
partitioning. The enzyme exhibits high physical stability, retaining
activity with incubation up to 55 °C or in culture medium for
>15 h at 37 °C. As a genetic reporter, NanoLuc may be configured
for high sensitivity or for response dynamics by appending a degradation
sequence to reduce intracellular accumulation. Appending a signal
sequence allows NanoLuc to be exported to the culture medium, where
reporter expression can be measured without cell lysis. Fusion onto
other proteins allows luminescent assays of their metabolism or localization
within cells. Reporter quantitation is achievable even at very low
expression levels to facilitate more reliable coupling with endogenous
cellular processes
Engineered Luciferase Reporter from a Deep Sea Shrimp Utilizing a Novel Imidazopyrazinone Substrate
Bioluminescence methodologies have been extraordinarily
useful
due to their high sensitivity, broad dynamic range, and operational
simplicity. These capabilities have been realized largely through
incremental adaptations of native enzymes and substrates, originating
from luminous organisms of diverse evolutionary lineages. We engineered
both an enzyme and substrate in combination to create a novel bioluminescence
system capable of more efficient light emission with superior biochemical
and physical characteristics. Using a small luciferase subunit (19
kDa) from the deep sea shrimp <i>Oplophorus gracilirostris</i>, we have improved luminescence expression in mammalian cells âŒ2.5
million-fold by merging optimization of protein structure with development
of a novel imidazopyrazinone substrate (furimazine). The new luciferase,
NanoLuc, produces glow-type luminescence (signal half-life >2 h)
with
a specific activity âŒ150-fold greater than that of either firefly
(<i>Photinus pyralis</i>) or <i>Renilla</i> luciferases
similarly configured for glow-type assays. In mammalian cells, NanoLuc
shows no evidence of post-translational modifications or subcellular
partitioning. The enzyme exhibits high physical stability, retaining
activity with incubation up to 55 °C or in culture medium for
>15 h at 37 °C. As a genetic reporter, NanoLuc may be configured
for high sensitivity or for response dynamics by appending a degradation
sequence to reduce intracellular accumulation. Appending a signal
sequence allows NanoLuc to be exported to the culture medium, where
reporter expression can be measured without cell lysis. Fusion onto
other proteins allows luminescent assays of their metabolism or localization
within cells. Reporter quantitation is achievable even at very low
expression levels to facilitate more reliable coupling with endogenous
cellular processes
Engineered Luciferase Reporter from a Deep Sea Shrimp Utilizing a Novel Imidazopyrazinone Substrate
Bioluminescence methodologies have been extraordinarily
useful
due to their high sensitivity, broad dynamic range, and operational
simplicity. These capabilities have been realized largely through
incremental adaptations of native enzymes and substrates, originating
from luminous organisms of diverse evolutionary lineages. We engineered
both an enzyme and substrate in combination to create a novel bioluminescence
system capable of more efficient light emission with superior biochemical
and physical characteristics. Using a small luciferase subunit (19
kDa) from the deep sea shrimp <i>Oplophorus gracilirostris</i>, we have improved luminescence expression in mammalian cells âŒ2.5
million-fold by merging optimization of protein structure with development
of a novel imidazopyrazinone substrate (furimazine). The new luciferase,
NanoLuc, produces glow-type luminescence (signal half-life >2 h)
with
a specific activity âŒ150-fold greater than that of either firefly
(<i>Photinus pyralis</i>) or <i>Renilla</i> luciferases
similarly configured for glow-type assays. In mammalian cells, NanoLuc
shows no evidence of post-translational modifications or subcellular
partitioning. The enzyme exhibits high physical stability, retaining
activity with incubation up to 55 °C or in culture medium for
>15 h at 37 °C. As a genetic reporter, NanoLuc may be configured
for high sensitivity or for response dynamics by appending a degradation
sequence to reduce intracellular accumulation. Appending a signal
sequence allows NanoLuc to be exported to the culture medium, where
reporter expression can be measured without cell lysis. Fusion onto
other proteins allows luminescent assays of their metabolism or localization
within cells. Reporter quantitation is achievable even at very low
expression levels to facilitate more reliable coupling with endogenous
cellular processes
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The revised Approved Instructional Resources score: An improved quality evaluation tool for online educational resources
BackgroundFree Open-Access Medical education (FOAM) use among residents continues to rise. However, it often lacks quality assurance processes and residents receive little guidance on quality assessment. The Academic Life in Emergency Medicine Approved Instructional Resources tool (AAT) was created for FOAM appraisal by and for expert educators and has demonstrated validity in this context. It has yet to be evaluated in other populations.ObjectivesWe assessed the AAT's usability in a diverse population of practicing emergency medicine (EM) physicians, residents, and medical students; solicited feedback; and developed a revised tool.MethodsAs part of the Medical Education Translational Resources: Impact and Quality (METRIQ) study, we recruited medical students, EM residents, and EM attendings to evaluate five FOAM posts with the AAT and provide quantitative and qualitative feedback via an online survey. Two independent analysts performed a qualitative thematic analysis with discrepancies resolved through discussion and negotiated consensus. This analysis informed development of an initial revised AAT, which was then further refined after pilot testing among the author group. The final tool was reassessed for reliability.ResultsOf 330 recruited international participants, 309 completed all ratings. The Best Evidence in Emergency Medicine (BEEM) score was the component most frequently reported as difficult to use. Several themes emerged from the qualitative analysis: for ease of use-understandable, logically structured, concise, and aligned with educational value. Limitations include deviation from questionnaire best practices, validity concerns, and challenges assessing evidence-based medicine. Themes supporting its use include evaluative utility and usability. The author group pilot tested the initial revised AAT, revealing a total score average measure intraclass correlation coefficient (ICC) of moderate reliability (ICC = 0.68, 95% confidence interval [CI] = 0 to 0.962). The final AAT's average measure ICC was 0.88 (95% CI = 0.77 to 0.95).ConclusionsWe developed the final revised AAT from usability feedback. The new score has significantly increased usability, but will need to be reassessed for reliability in a broad population