4,146 research outputs found
Trait anxiety does not correlate with metacognitive confidence or reminder usage in a delayed intentions task
Setting external reminders provides a convenient way to reduce cognitive demand and ensure accurate retrieval of information for prospective tasks. Recent experimental evidence has demonstrated that the decision to offload cognitive information to external resources is guided by metacognitive belief, i.e. individuals’ confidence in their unaided ability. Other work has also suggested a relationship between metacognitive belief and trait anxiety. In the present study (N=300), we bridged these two areas by investigating whether trait anxiety correlated with metacognitive belief — and consequently — propensity to offload information in a delayed intentions paradigm. Participants received a financial reward based on their ability to remember targets. However, participants could take a reduced reward per target if they decided to use reminders. We replicated previous findings that participants were biased to use more reminders than would be optimal, and this bias was correlated with metacognitive judgements. However, we show no evidence that trait anxiety held a relationship with metacognitive belief or reminder usage. Indeed, Bayesian analyses strongly favoured the null. Therefore, variation in self-reported trait anxiety does not necessarily influence confidence and strategy when participants remember delayed intentions
The Cultures of Student Affairs and Academic Affairs Collaboration: An Examination of Typology in Higher Education Subcultures
This article reviews existing literature on the similarities and differences in personality and learning typologies of student affairs and academic affairs professionals and faculty. It discusses how knowledge of personality and learning typologies can be used to establish successful collaboration between institutional subcultures. Implications for building intercultural collaboration are presented
The Cultures of Student Affairs and Academic Affairs Collaboration: An Examination of Typology in Higher Education Subcultures
This article reviews existing literature on the similarities and differences in personality and learning typologies of student affairs and academic affairs professionals and faculty. It discusses how knowledge of personality and learning typologies can be used to establish successful collaboration between institutional subcultures. Implications for building intercultural collaboration are presented
Electron Acceleration and Time Variability of High Energy Emission from Blazars
Blazars are known to emit a broad band emission from radio to gamma-rays with
rapid time variations, particularly, in X- and gamma-rays. Synchrotron
radiation and inverse Compton scattering are thought to play an important role
in emission and the time variations are likely related to the acceleration of
nonthermal electrons. As simultaneous multiwavelength observations with
continuous time spans are recently available, some characteristics of electron
acceleration are possibly inferred from the spectral changes of high energy
emission. In order to make such inferences, we solve the time-dependent kinetic
equations of electrons and photons simultaneously using a simple model for
electron acceleration. We then show how the time variations of emission are
dependent on electron acceleration. We also present a simple model for a flare
in X-rays and TeV gamma-rays by temporarily changing the acceleration
timescale. Our model will be used, in future, to analyze observed data in
detail to obtain information on electron acceleration in blazars.Comment: 24 pages, 12 figures, accepted by the Astrophysical Journa
Energetics of Tev Blazars and Physical Constraints on their Emission Regions
Using multi-frequency spectra from TeV blazars in quiescent states, we obtain
the physical parameters of the emission region of blazars within the framework
of the one-zone synchrotron self-Compton (SSC) model. We numerically calculate
the steady-state energy spectra of electrons by self-consistently taking into
account the effects of radiative cooling with a proper account of the
Klein-Nishina effects. Here electrons are assumed to be injected with a
power-law spectrum and to escape on a finite time scale, which naturally leads
to the existence of a break energy scale. Although we do not use time
variabilities but utilize a model of electron escape to constrain the size of
the emission region, the resultant size turns out to be similar to that
obtained based on time variabilities. Through detailed comparison of the
predicted emission spectra with observations, we find that for Mrk 421, Mrk
501, and PKS 2155--304, the energy density of relativistic electrons is about
an order of magnitude larger than that of magnetic fields with an uncertainty
within a factor of a few.Comment: Accepted for publication in Ap
Temporal and Spectral Variabilities of High Energy Emission from Blazars Using Synchrotron Self-Compton Models
Multiwavelength observations of blazars such as Mrk 421 and Mrk 501 show that
they exhibit strong short time variabilities in flare-like phenomena. Based on
the homogeneous synchrotron self-Compton (SSC) model and assuming that time
variability of the emission is initiated by changes in the injection of
nonthermal electrons, we perform detailed temporal and spectral studies of a
purely cooling plasma system. One important parameter is the total injected
energy E and we show how the synchrotron and Compton components respond as E
varies. We discuss in detail how one could infer important physical parameters
using the observed spectra. In particular, we could infer the size of the
emission region by looking for exponential decay in the light curves. We could
also test the basic assumption of SSC by measuring the difference in the rate
of peak energy changes of synchrotron and SSC peaks. We also show that the
trajectory in the photon-index and flux plane evolves clockwise or
counter-clockwise depending on the value of E and observed energy bands.Comment: 35 pages, 18 figures, accepted by the Astrophysical Journa
The Politics of Commerce : The Congress of Chambers of Commerce of the Empire, 1886-1914
Peer reviewedPublisher PD
Rapid Optical Fluctuations in the Black Hole Binary, V4641 Sgr
We report on unprecedented short-term variations detected in the optical flux
from the black hole binary system, V4641 Sgr. Amplitudes of the optical
fluctuations were larger at longer time scales, and surprisingly reached ~60%
around a period of ~10 min. The power spectra of fluctuations are characterized
by a power law. It is the first case in black hole binaries that the optical
emission was revealed to show short-term and large-amplitude variations given
by such a power spectrum. The optical emission from black hole binaries is
generally dominated by the emission from the outer portion of an accretion
disc. The rapid optical fluctuations however indicate that the emission from an
inner accretion region significantly contributes to the optical flux. In this
case, cyclo-synchrotron emission associated with various scales of magnetic
flares is the most promising mechanism for the violently variable optical
emission.Comment: 5 pages, 2 figures, accepted for publication in PAS
Protein profiling in hepatocellular carcinoma by label-free quantitative proteomics in two west african populations.
Background Hepatocellular Carcinoma is the third most common cause of cancer related death worldwide, often diagnosed by measuring serum AFP; a poor performance stand-alone biomarker. With the aim of improving on this, our study focuses on plasma proteins identified by Mass Spectrometry in order to investigate and validate differences seen in the respective proteomes of controls and subjects with LC and HCC. Methods Mass Spectrometry analysis using liquid chromatography electro spray ionization quadrupole time-of-flight was conducted on 339 subjects using a pooled expression profiling approach. ELISA assays were performed on four significantly differentially expressed proteins to validate their expression profiles in subjects from the Gambia and a pilot group from Nigeria. Results from this were collated for statistical multiplexing using logistic regression analysis. Results Twenty-six proteins were identified as differentially expressed between the three subject groups. Direct measurements of four; hemopexin, alpha-1-antitrypsin, apolipoprotein A1 and complement component 3 confirmed their change in abundance in LC and HCC versus control patients. These trends were independently replicated in the pilot validation subjects from Nigeria. The statistical multiplexing of these proteins demonstrated performance comparable to or greater than ALT in identifying liver cirrhosis or carcinogenesis. This exercise also proposed preliminary cut offs with achievable sensitivity, specificity and AUC statistics greater than reported AFP averages. Conclusions The validated changes of expression in these proteins have the potential for development into high-performance tests usable in the diagnosis and or monitoring of HCC and LC patients. The identification of sustained expression trends strengthens the suggestion of these four proteins as worthy candidates for further investigation in the context of liver disease. The statistical combinations also provide a novel inroad of analyses able to propose definitive cut-offs and combinations for evaluation of performance
Rapid, ultra low coverage copy number profiling of cell-free DNA as a precision oncology screening strategy.
Current cell-free DNA (cfDNA) next generation sequencing (NGS) precision oncology workflows are typically limited to targeted and/or disease-specific applications. In advanced cancer, disease burden and cfDNA tumor content are often elevated, yielding unique precision oncology opportunities. We sought to demonstrate the utility of a pan-cancer, rapid, inexpensive, whole genome NGS of cfDNA approach (PRINCe) as a precision oncology screening strategy via ultra-low coverage (~0.01x) tumor content determination through genome-wide copy number alteration (CNA) profiling. We applied PRINCe to a retrospective cohort of 124 cfDNA samples from 100 patients with advanced cancers, including 76 men with metastatic castration-resistant prostate cancer (mCRPC), enabling cfDNA tumor content approximation and actionable focal CNA detection, while facilitating concordance analyses between cfDNA and tissue-based NGS profiles and assessment of cfDNA alteration associations with mCRPC treatment outcomes. Therapeutically relevant focal CNAs were present in 42 (34%) cfDNA samples, including 36 of 93 (39%) mCRPC patient samples harboring AR amplification. PRINCe identified pre-treatment cfDNA CNA profiles facilitating disease monitoring. Combining PRINCe with routine targeted NGS of cfDNA enabled mutation and CNA assessment with coverages tuned to cfDNA tumor content. In mCRPC, genome-wide PRINCe cfDNA and matched tissue CNA profiles showed high concordance (median Pearson correlation = 0.87), and PRINCe detectable AR amplifications predicted reduced time on therapy, independent of therapy type (Kaplan-Meier log-rank test, chi-square = 24.9, p < 0.0001). Our screening approach enables robust, broadly applicable cfDNA-based precision oncology for patients with advanced cancer through scalable identification of therapeutically relevant CNAs and pre-/post-treatment genomic profiles, enabling cfDNA- or tissue-based precision oncology workflow optimization
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