1,158 research outputs found
Conflict, Trust, and Effectiveness in Teams Performing Complex Tasks: A Study of Temporal Patterns
In this study we analyze the evolution of intra-team conflict and trust in teams that perform complex tasks. Using a longitudinal research design with six time intervals over a period of ten months, we collected data on 41 teams. Our findings suggest the existence of two distinct temporal patterns. One pattern develops in a stable manner and is characterized by high levels of trust and relatively low levels of task and relationship conflict. The other pattern is unstable with low, deteriorating levels of trust and high, amplifying levels of task and relationship conflict. These patterns are associated with significant differences in team effectiveness. On a self-perception as well as a stakeholder measure of team effectiveness, teams with stable patterns outperformed teams with unstable patterns.management and organization theory ;
A sentence completion procedure as an alternative to the Autobiographical Memory Test for assessing overgeneral memory in non-clinical populations
Overgeneral memory (OGM) has been proposed as a vulnerability factor for depression (Williams et al., 2007) or depressive reactivity to stressful life-events (e.g., Gibbs & Rude, 2004). Traditionally, a cue word procedure known as the Autobiographical Memory Test (AMT; Williams & Broadbent, 1986) is used to assess OGM. Although frequently and validly used in clinical populations, there is evidence suggesting that the AMT is insufficiently sensitive to measure OGM in non-clinical groups. Study 1 evaluated the usefulness of a sentence completion method to assess OGM in non-clinical groups, as an alternative to the AMT. Participants were 197 students who completed the AMT, the Sentence Completion for Events from the Past Test (SCEPT), a depression measure, and visual analogue scales assessing ruminative thinking. Results showed that the mean proportion of overgeneral responses was markedly higher for the SCEPT than for the standard AMT. Also, overgeneral responding on the SCEPT was positively associated to depression scores and depressive rumination scores, whereas overgeneral responding on the AMT was not. Results suggest that the SCEPT, relative to the AMT, is a more sensitive instrument to measure OGM, at least in non-clinical populations. Study 2 further showed that this enhanced sensitivity is most likely due to the omission of the instruction to be specific rather than to the SCEPT's sentence completion format (as opposed to free recall to cue words)
Scrutinizing the mechanisms underlying the induction of anemia of inflammation through GPI-mediated modulation of macrophage activation in a model of African trypanosomiasis
Benchmarking microbiome transformations favors experimental quantitative approaches to address compositionality and sampling depth biases
While metagenomic sequencing has become the tool of preference to study host-associated microbial communities, downstream analyses and clinical interpretation of microbiome data remains challenging due to the sparsity and compositionality of sequence matrices. Here, we evaluate both computational and experimental approaches proposed to mitigate the impact of these outstanding issues. Generating fecal metagenomes drawn from simulated microbial communities, we benchmark the performance of thirteen commonly used analytical approaches in terms of diversity estimation, identification of taxon-taxon associations, and assessment of taxon-metadata correlations under the challenge of varying microbial ecosystem loads. We find quantitative approaches including experimental procedures to incorporate microbial load variation in downstream analyses to perform significantly better than computational strategies designed to mitigate data compositionality and sparsity, not only improving the identification of true positive associations, but also reducing false positive detection. When analyzing simulated scenarios of low microbial load dysbiosis as observed in inflammatory pathologies, quantitative methods correcting for sampling depth show higher precision compared to uncorrected scaling. Overall, our findings advocate for a wider adoption of experimental quantitative approaches in microbiome research, yet also suggest preferred transformations for specific cases where determination of microbial load of samples is not feasible
Local mapping of dissipative vortex motion
We explore, with unprecedented single vortex resolution, the dissipation and
motion of vortices in a superconducting ribbon under the influence of an
external alternating magnetic field. This is achieved by combing the phase
sensitive character of ac-susceptibility, allowing to distinguish between the
inductive-and dissipative response, with the local power of scanning Hall probe
microscopy. Whereas the induced reversible screening currents contribute only
inductively, the vortices do leave a fingerprint in the out-of-phase component.
The observed large phase-lag demonstrates the dissipation of vortices at
timescales comparable to the period of the driving force (i.e. 13 ms). These
results indicate the presence of slow microscopic loss mechanisms mediated by
thermally activated hopping transport of vortices between metastable states.Comment: 5 pages, 2 figure
Simulating climate change impacts on forests and associated vascular epiphytes in a subtropical island of East Asia
Autobiographical Memory Specificity and Emotional Disorder
The authors review research showing that when recalling autobiographical events, many emotionally disturbed patients summarize categories of events rather than retrieving a single episode. The mechanisms underlying such overgeneral memory are examined, with a focus on M. A. Conway and C. W. Pleydell-Pearce's (2000) hierarchical search model of personal event retrieval. An elaboration of this model is proposed to account for overgeneral memory, focusing on how memory search can be affected by (a) capture and rumination processes, when mnemonic information used in retrieval activates ruminative thinking; (b) functional avoidance, when episodic material threatens to cause affective disturbance; and (c) impairment in executive capacity and control that limits an individual's ability to remain focused on retrieval in the face of distraction
The influence of superabsorbent polymers and nanosilica on the hydration process and microstructure of cementitious mixtures
Superabsorbent polymers (SAPs) are known to mitigate the development of autogenous shrinkage in cementitious mixtures with a low water-to-cement ratio. Moreover, the addition of SAPs promotes the self-healing ability of cracks. A drawback of using SAPs lies in the formation of macropores when the polymers release their absorbed water, leading to a reduction of the mechanical properties. Therefore, a supplementary material was introduced together with SAPs, being nanosilica, in order to obtain an identical compressive strength with respect to the reference material without additives. The exact cause of the similar compressive behaviour lies in the modification of the hydration process and subsequent microstructural development by both SAPs and nanosilica. Within the present study, the effect of SAPs and nanosilica on the hydration progress and the hardened properties is assessed. By means of isothermal calorimetry, the hydration kinetics were monitored. Subsequently, the quantity of hydration products formed was determined by thermogravimetric analysis and scanning electron microscopy, revealing an increased amount of hydrates for both SAP and nanosilica blends. An assessment of the pore size distribution was made using mercury intrusion porosimetry and demonstrated the increased porosity for SAP mixtures. A correlation between microstructure and the compressive strength displayed its influence on the mechanical behaviour
SoLid : Search for Oscillations with Lithium-6 Detector at the SCK-CEN BR2 reactor
Sterile neutrinos have been considered as a possible explanation for the recent reactor and Gallium anomalies arising from reanalysis of reactor flux and calibration data of previous neutrino experiments. A way to test this hypothesis is to look for distortions of the anti-neutrino energy caused by oscillation from active to sterile neutrino at close stand-off (similar to 6-8m) of a compact reactor core. Due to the low rate of anti-neutrino interactions the main challenge in such measurement is to control the high level of gamma rays and neutron background.
The SoLid experiment is a proposal to search for active-to-sterile anti-neutrino oscillation at very short baseline of the SCK center dot CEN BR2 research reactor.
This experiment uses a novel approach to detect anti-neutrino with a highly segmented detector based on Lithium-6. With the combination of high granularity, high neutron-gamma discrimination using 6LiF:ZnS(Ag) and precise localization of the Inverse Beta Decay products, a better experimental sensitivity can be achieved compared to other state-of-the-art technology. This compact system requires minimum passive shielding allowing for very close stand off to the reactor. The experimental set up of the SoLid experiment and the BR2 reactor will be presented. The new principle of neutrino detection and the detector design with expected performance will be described. The expected sensitivity to new oscillations of the SoLid detector as well as the first measurements made with the 8 kg prototype detector deployed at the BR2 reactor in 2013-2014 will be reported
Atmospheric electric conductivity measurements over the Indian Ocean during the Indian Antarctic Expedition in 1996-1997
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