Cavitation Inception - A Selective Review

This paper reviews recent developments in selected cavitation research areas which have been active mainly within the past two years. The new understanding resulting from this work is summarized. Research topics discussed are cavitation inception on smooth surfaces, on vortex cavitation and scaling, on the measurement of cavitation nuclei, and on the effects of polymer additives. Because of the selective nature of the review, a fairly comprehensive listing of recent contributions to the literature on these and related aspects of cavitation research is an essential part of the exposition

Tunneling Anisotropic Magnetoresistance of Helimagnet Tunnel Junctions

We theoretically investigate the angular and spin dependent transport in normal-metal/helical-multiferroic/ferromagnetic heterojunctions. We find a tunneling anisotropic magnetoresistance (TAMR) effect due to the spiral magnetic order in the tunnel junction and to an effective spin-orbit coupling induced by the topology of the localized magnetic moments in the multiferroic spacer. The predicted TAMR effect is efficiently controllable by an external electric field due to the magnetoelectric coupling

Menu engineering to encourage sustainable food choices when dining out: An online trial of priced-based decoys

Menu-based ‘nudges’ hold promise as effective ways to encourage a shift away from ruminant meat and towards more environmentally friendly plant-based options when dining out. One example of a menu-based nudge is including an inferior ‘decoy’ option to existing items on menus. Decoys have been shown to influence decision-making in other domains (e.g. Lichters, Bengart, Sarstedt, & Vogt, 2017), but have yet to be used to promote sustainable food choices. Two online randomized controlled trials tested whether the addition of higher priced ‘decoy’ vegetarian options to menus influenced the number of diners choosing a ‘target’ vegetarian option. Adjusted Generalized Estimating Equations on data from four menu conditions showed no main effect of intervention group in study 1 (decoy absent vs. decoy present; odds ratio (OR) 1.08 (95% Confidence Interval (CI) 0.45 to 2.57). Replicating the trial in study 2 across seven menu conditions and testing a more expensive decoy also showed no main effect of the intervention (decoy absent vs. decoy present; OR 0.68 (95% CI 0.41 to 1.12). Further analyses revealed that our price-based decoy strategy (a £30% price increase) did not significantly influence the numbers who chose the inferior decoy dish, potentially due to the fact that dish choices were purely hypothetical. Further research is now needed to clarify which attributes of a dish (e.g. taste, portion size, signature ingredients etc.) are optimal candidates for use as decoys and testing these in real world choice contexts

Dynamic Network Mechanisms of Relational Integration

A prominent hypothesis states that specialized neural modules within the human lateral frontopolar cortices (LFPCs) support “relational integration” (RI), the solving of complex problems using inter-related rules. However, it has been proposed that LFPC activity during RI could reflect the recruitment of additional “domain-general” resources when processing more difficult problems in general as opposed to RI specifi- cally. Moreover, theoretical research with computational models has demonstrated that RI may be supported by dynamic processes that occur throughout distributed networks of brain regions as opposed to within a discrete computational module. Here, we present fMRI findings from a novel deductive reasoning paradigm that controls for general difficulty while manipulating RI demands. In accordance with the domain- general perspective, we observe an increase in frontoparietal activation during challenging problems in general as opposed to RI specifically. Nonetheless, when examining frontoparietal activity using analyses of phase synchrony and psychophysiological interactions, we observe increased network connectivity during RI alone. Moreover, dynamic causal modeling with Bayesian model selection identifies the LFPC as the effective connectivity source. Based on these results, we propose that during RI an increase in network connectivity and a decrease in network metastability allows rules that are coded throughout working memory systems to be dynamically bound. This change in connectivity state is top-down propagated via a hierarchical system of domain-general networks with the LFPC at the apex. In this manner, the functional network perspective reconciles key propositions of the globalist, modular, and computational accounts of RI within a single unified framework

The physiological effects of Transcranial Electrical Stimulation do not apply to parameters commonly used in studies of Cognitive Neuromodulation

Transcranial direct current stimulation (tDCS) and transcranial random noise stimulation (tRNS) have been claimed to produce many remarkable enhancements in perception, cognition, learning and numerous clinical conditions. The physiological basis of the claims for tDCS rests on the finding that 1 mA of unilateral anodal stimulation increases cortical excitation and 1 mA of cathodal produces inhibition. Here we show that these classic excitatory and inhibitory effects do not hold for the bilateral stimulation or 2 mA intensity conditions favoured in cognitive enhancement experiments. This is important because many, including some of the most salient claims are based on experiments using 2 mA bilateral stimulation. The claims for tRNS are also based on unilateral stimulation. Here we show that, again the classic excitatory effects of unilateral tRNS do not extend to the bilateral stimulation preferred in enhancement experiments. Further, we show that the effects of unilateral tRNS do not hold when one merely doubles the stimulation duration. We are forced to two conclusions: (i) that even if all the data on TES enhancements are true, the physiological explanations on which the claims are based are at best not established but at worst false, and (ii) that we cannot explain, scientifically at least, how so many experiments can have obtained data consistent with physiological effects that may not exist

Gaseous Photocatalytic Oxidation of Formic Acid over TiO2: A Comparison between the Charge Carrier Transfer and Light-Assisted Mars-van Krevelen Pathways

Under light illumination, it is usually considered that photocatalytic oxidations of organics such as volatile organic compounds over semiconductors are driven by the transfer of photogenerated carriers. Some studies also proposed that the photocatalytic oxidations might take place according to the light-assisted Mars–van Krevelen (MvK) pathway that involved the participation of lattice oxygens under aerobic conditions. Based on the concept of the MvK mechanism, the current work first gives an elaboration on the light-assisted MvK pathway and its intrinsic difference from the charge carrier transfer pathway. We then examined which one of these two mechanisms is responsible for the the photocatalytic oxidation of formic acid over TiO2. Comprehensive experiments, including apparent kinetics, online electric conductances, vacuum electric conductances, online optical transmittances, and first principle calculations, were carried out to discuss this problem. The results showed that the photocatalytic oxidations of formic acid over TiO2 dominantly follow the charge carrier transfer pathway at both low and elevated temperatures, the light-assisted MvK mechanism could not play a major role, and there was also no transition from the charge carrier transfer to the light-assisted MvK mechanism with an increase of reaction temperature