Proactive inhibitory control: a general biasing account

Flexible behavior requires a control system that can inhibit actions in response to changes in the environment. Recent studies suggest that people proactively adjust response parameters in anticipation of a stop signal. In three experiments, we tested the hypothesis that proactive inhibitory control involves adjusting both attentional and response settings, and we explored the relationship with other forms of proactive and anticipatory control. Subjects responded to the color of a stimulus. On some trials, an extra signal occurred. The response to this signal depended on the task context subjects were in: in the ‘ignore’ context, they ignored it; in the ‘stop’ context, they had to withhold their response; and in the ‘double-response’ context, they had to execute a secondary response. An analysis of event-related brain potentials for no-signal trials in the stop context revealed that proactive inhibitory control works by biasing the settings of lower-level systems that are involved in stimulus detection, action selection, and action execution. Furthermore, subjects made similar adjustments in the double-response and stop-signal contexts, indicating an overlap between various forms of proactive action control. The results of Experiment 1 also suggest an overlap between proactive inhibitory control and preparatory control in task-switching studies: both require reconfiguration of task-set parameters to bias or alter subordinate processes. We conclude that much of the top-down control in response inhibition tasks takes place before the inhibition signal is presente

Application of UV-C irradiation prevented a severe outbreak of proliferative kidney disease in rainbow trout aquaculture

There is an urgent need to establish protocols on how to protect salmonids in aquaculture from outbreaks of proliferative kidney disease (PKD). For this purpose, systems for a continuous application of peracetic acid (PAA, 0.1 mg l−1) and of ultraviolet C light (UV-C, 323.5− 158.6 mW s cm−2) were installed in the inlet of raceway-channels within a sub-unit of a commercial rainbow trout Oncorhynchus mykiss farm. After 127 d of rearing, a fish health examination was conducted. Fish in the control and PAA treatment groups showed signs of PKD. In contrast, fish in the UV-C treatment group showed almost no signs of disease based on clinical examinations and necropsy. This observation indicates that UV-C irradiation could be a promising tool to protect fish from PKD in the future

Modelling Robust Feedback Control Mechanisms That Ensure Reliable Coordination of Histone Gene Expression with DNA Replication

Funding: Andrea Christopher was supported by the University of Aberdeen through a Milner Studentship. Heike Hameister was supported by a Postgraduate Research Studentship of the University of Aberdeen. Oliver Ebenhöh was supported by the University of Aberdeen and the Deutsche Forschungsgemeinschaft [Cluster of Excellence on Plant Sciences, CEPLAS (EXC 1028)]. Berndt Müller was supported by the University of Aberdeen. Ekkehard Ullner was supported by the Scottish Universities Life Sciences Alliance (SULSA). The funders provided support in the form of salaries for authors but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section. Heike Hameister is currently employed by Merck Serono GmbH. Merck Serono GmbH did not provide any support for this work and did not have any role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. This does not alter our adherence to PLOS ONE policies on sharing data and materials.Peer reviewedPublisher PD

Tacticity dependence of single chain polymer folding

Precision polymerization techniques offer the exciting opportunity to manufacture single-chain nanoparticles (SCNPs) with intramolecular crosslinks placed in specific positions along the polymer chain. Earlier studies showed that synthetic polymer chains can fold into defined SCNP conformations through a reversible two-state process, similar to that observed for small peptides and proteins – yet far behind in its structural sophistication. While the natural structures of proteins arise from polypeptides of perfectly defined stereochemistry, the role of main-chain stereochemistry on SCNP folding remains largely unexplored. To investigate the effect of tacticity on SCNP architectures, the development of specific simulation strategies is critical to provide reliable data. Herein, we investigate the structural transitions of SCNPs of different stereochemistries, i.e. atactic, syndiotactic and isotactic of various lengths (L = 10 to L = 30) using all-atom Monte-Carlo simulations. The results indicate that structural transitions occur in syndiotactic polymers at lower temperature compared to atactic and isotactic polymer chains. The effect of main chain stereochemistry on the transition temperature was found to be especially pronounced for shorter polymer chains of length L = 10 to L = 20

Spatially modulated broad-area lasers for narrow lateral far-field divergence

A novel laser design is presented that combines a longitudinal-lateral gain-loss modulation with an additional phase tailoring achieved by etching rectangular trenches. At 100 A pulsed operation, simulations predict a far-field profile with 0.3° full width at half maximum (ΘFWHM=0.3∘) where a 0.4°-wide main lobe contains 40% of the emitted optical output power (Θ40%=0.4∘). While far-field measurements of these structured lasers emitting 10 ns long pulses with 35 W peak power confirm a substantial enhancement of radiation within the central 1∘ angular range, the measured far-field intensity outside of the obtained central peak remains high

Spatially modulated broad-area lasers for narrow lateral far-field divergence

A novel laser design is presented that combines a longitudinal-lateral gain-loss modulation with an additional phase tailoring achieved by etching rectangular trenches. At 100 A pulsed operation, simulations predict a far-field profile with 0.3-degree full width at half maximum where a 0.4-degree-wide main lobe contains 40% of the emitted optical output power. While far-field measurements of these structured lasers emitting 10 ns long pulses with 35 W peak power confirm a substantial enhancement of radiation within the central one-degree angular range, the measured far-field intensity outside of the obtained central peak remains high