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A growth mode of pentacene thin films deposited by high vacuum sublimation where the morphology versus thickness h "rings" back and forth between rough 3D films with pyramid islands and smooth 2D films with ziqqurat islands is discovered. The roughness σ versus h exhibits seamless coherent oscillations whose amplitude and wavelength increase as integer multiples of 1.5 ML thickness. The quantized oscillations are reconducted to dynamic wetting/dewetting transitions involving the upper layers of pentacene film. Importantly, the transconductance of organic field effect transistors, either in solid state or electrolyte‐gated, exhibits antiphase oscillations with one‐decade swing. Charge mobilities in the wetting regime reach 0.1 cm2 V−1 s−1, in line with high‐end values reported for thin‐film pentacene transistors. Controlling this growth mode enables the limitations of charge transport imposed by the roughening transition to be overcome, a universal feature of high vacuum growth to date. [ABSTRACT FROM AUTHOR]

Multi‐electrode arrays with 3D micropillars allow the recording of electrophysiological signals in vitro with higher precision and signal‐to‐noise ratio than planar arrays. This is the result of the tight interaction between the 3D electrode and the cell membrane. Most 3D electrodes are manufactured on rigid substrates and their integration on flexible substrates is largely unexplored. Here, a straightforward approach is presented for fabricating soft interfaces featuring 3D poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) micropillars on a soft flexible substrate made of polydimethylsiloxane (PDMS). Large‐area isotropic arrays of PEDOT:PSS micropillars with tailored geometric area, surface properties, and electrochemical characteristics are fabricated via a combination of soft‐lithography and electrodeposition. A 60% increase in capacitance is achieved for high density micropillars compared to planar electrodes and this is found to be correlated with the increased electroactive surface area. Furthermore, 3D PEDOT:PSS micropillars support adhesion, growth and differentiation of SH‐SY5Y cells, and influence the direction of neurite outgrowth. Finally, by virtue of their elasticity, soft micropillars act as excellent anchoring loci for elongating neurites, facilitating their bending and twisting around the micropillar, increasing the number of contact points between the cells and the electrode, a key requirement to obtain high performance neural interfaces. [ABSTRACT FROM AUTHOR]

Successful translation of organic transistors as sensors and transducers to clinical settings is hampered by safety and stability issues. The operation of such devices demands driving voltages across the biotic/abiotic interface, which may result in undesired electrochemical reactions that may harm both the patient and the device. In this study, a novel operational mode is presented for electrolyte‐gated organic transistors that avoid these drawbacks: the common‐drain/grounded‐source configuration. This approach reverts the standard common‐source/common‐ground configuration and achieves maximum signal amplification while applying null net bias across the electrolyte, with no parasitic currents. The viability of the proposed configuration is demonstrated by recording in vivo the somatosensory evoked activity from the barrel cortex of rats. The main inherent advantage of transistors with respect to passive electrodes is preserved in the proposed scheme: a superior signal‐to‐noise ratio is achieved which enables the detection of evoked activity at the single‐trial level. Then, common‐drain/grounded‐source organic transistors are proposed as ideal candidate devices for a harmless translational recording platform. [ABSTRACT FROM AUTHOR]

Organic neuromorphic devices mimic signal processing features of biological synapses, with short‐term plasticity, STP, modulated by the frequency of the input voltage pulses. Here, an artificial synapse, made of intracortical microelectrodes, is demonstrated that exhibits either depressive or facilitative STP. The crossover between the two STP regimes is controlled by the frequency of the input voltage. STP features are described with an equivalent circuit where an inductance component is introduced in parallel with the RC circuit associated with poly(3,4‐ethylenedioxythiophene)/polystyrene sulfonate (PEDOT/PSS)||electrolyte interface. The proposed RLC circuit explains the physical origin of the observed STP and its two timescales in terms of charge build up in PEDOT/PSS. [ABSTRACT FROM AUTHOR]

The home advantage and unconscious referee bias are two well-documented phenomena in professional sports, especially in association football. Among the various factors determining them, the crowd noise is considered as one of the most relevant; yet, the majority of previous studies could not isolate its contribution. The possibility to study the effects of crowd noise – or, better, of its absence – in an ecological context was given by the matches played behind closed doors due to the COVID-19 pandemic. The aim of the present study was to investigate whether home advantage and referee bias still occur (and to what extent) during matches played in absence of spectators. In particular, the focus was on the first and second divisions of the top four countries in the UEFA ranking, for a total of 841 matches behind closed doors. The hypothesis was that, if these phenomena are largely due to the effect of crowd noise, the absence of spectators should reduce their occurrence. Various parameters for each of the two phenomena were considered, and the analyses revealed a reduction of home advantage and the absence of referee bias. The results bring further support to the claim that, among all the factors contributing to home advantage and referee bias, crowd noise has a relevant role. Thus, spectators can significantly contribute to determine the dynamics and the outcomes of professional football matches. [ABSTRACT FROM AUTHOR]

The Impact of Event Scale–Revised (IES‐R) is a widely used self‐report questionnaire used to assess symptoms of posttraumatic stress disorder (PTSD). Although the IES‐R has been translated and validated in multiple languages, no previous version has employed the Arabic dialect commonly spoken in Syria. The present work aimed to assess the psychometric properties of a Syrian Arabic version of the IES‐R. Syrian citizens (N = 288) living in refugee camps in Turkey were administered the Syrian Arabic IES‐R as part of a humanitarian aid project focused on providing psychological assistance. The data were analyzed with respect to 10 previously published factor solutions. We found that the best‐fitting model was a four‐factor structure that included factors involving Avoidance–Numbing, Intrusion, Hyperarousal, and Sleep Disturbance. The model showed strong measurement invariance between male and female subsamples, allowing for meaningful comparisons of the factor means. Overall, the present findings support the validity of a new version of the IES‐R, which can be used by both researchers and clinicians responding to the urgent need for psychological care for Syrian refugees fleeing war‐related violence. [ABSTRACT FROM AUTHOR]

In a recent paper by Casasanto and Pitt (2019), the authors addressed a debate regarding the role of order and magnitude in SNARC and SNARC‐like effects. Their position is that all these effects can be explained by order, while magnitude could only account for a subset of evidence. Although we agree that order can probably explain the majority of these effects, in this commentary we argue that magnitude is still relevant, since there is evidence that cannot be explained based on ordinality alone. We argue that SNARC‐like effects can occur for magnitudes not clearly characterized by overlearned ordinality and that magnitude can prevail on order, when the two are pitted against each other. Finally, we propose that different interpretations of the role of order and magnitude depend on the interaction of stimulus properties and task demands. [ABSTRACT FROM AUTHOR]

We sought to examine whether the relationship between recovery–stress factors and performance would differ at the beginning (Stage 1) and the end (Final Stage) of a multi-stage cycling competition. Sixty-seven cyclists with a mean age of 21.90 years (SD = 1.60) and extensive international experience participated in the study. The cyclists responded to the Recovery–Stress Questionnaire for Athletes (RESTQ-Sport) and rated their performance (1 = extremely poorto 10 = excellent) in respect to the first and last stage. Two step-down multiple regression models were used to estimate the relationship among recovery (nine factors; e.g.Physical Recovery,Sleep Quality) and stress factors (10 factors; e.g.Lack of Energy,Physical Complaints), as assessed by the RESTQ-Sport and in relation to performance. Model 1 pertained to Stage 1, whereas Model 2 used data from the Final Stage. The final Model 1 revealed thatPhysical Recovery(β = .46,p = .01),Injury(β = −.31,p = .01) andGeneral Well-being(β = −.26,p = .04) predicted performance in Stage 1 (R2 = .21). The final Model 2 revealed a different relationship between recovery–stress factors and performance. Specifically, being aclimber(β = .28,p = .01),Conflicts/Pressure(β = .33,p = .01), andLack of Energy(β = −.37,p = .01) were associated with performance at the Final Stage (R2 = .19). Collectively, these results suggest that the relationship among recovery and stress factors changes greatly over a relatively short period of time, and dynamically influences performance in multi-stage competitions. [ABSTRACT FROM AUTHOR]

Charge transfer at organic‐organic heterojunctions is fundamental to several organic electronics devices, including light‐emitting diodes, photovoltaic cells, light‐emitting transistors, and ambipolar field‐effect transistors. Here, probe charge transfer (CT) processes during the formation of an organic‐organic heterojunction are probed by performing in situ real‐time electrical characterization during the growth of pentacene/C60 ambipolar transistors. N‐type C60 channel formation follows two different percolation pathways, one being associated to linear C60 structures growing along pentacene grain boundaries and the other to C60 island percolation. Upon n‐channel formation a shift of pentacene p‐type transfer characteristics is observed, which is attributed to CT across the heterojunction interface as a result of Fermi level alignment. The findings allow estimation of the energy of thermally accessible CT‐states and their mobility along the interface. Finally, a model is proposed that relates the amount of transferred charge to details in the bilayer morphology and layer thicknesses. The model relies on the capacitive coupling between C60 and pentacene in the accumulation layer, which is consistent with a single hole transport channel. [ABSTRACT FROM AUTHOR]

A simple, versatile, rapid, and inexpensive procedure based on the immersion method is developed to fabricate chemical gradients on chemically activated Si/SiO2 surfaces by a trichloro (1H,1H,2H,2H-perfluorooctyl) silane self-assembly monolayer (SAM). Contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy data based on the intensity of the signals of C1s and F1s, which progressively increase, indicate that the surface is characterized by the presence of increasing amounts of the SAM along the gradient direction. Experimental conditions are optimized by maximizing the variation of the contact angle of water drops at the starting and the ending points of the gradient. The application of the chemical gradient to droplet motion is demonstrated. The results are rationalized by dissipative particle dynamics simulations that well match the observed contact angles and the velocities of the drops. The simulations also show that the intrinsic nature of the gradient affects the velocity of the motion. [ABSTRACT FROM AUTHOR]

The photochemical core of every photosynthetic apparatus is the reaction center, a transmembrane enzyme that converts photons into charge‐separated states across the biological membrane with an almost unitary quantum yield. A light‐responsive organic transistor architecture, which converts light into electrical current by exploiting the efficiency of this biological machinery, is presented. Proper surface tailoring enables the integration of the bacterial reaction center as photoactive element in organic transistors, allowing the transduction of its photogenerated voltage into photomodulation of the output current up to two orders of magnitude. This device architecture, termed light‐responsive electrolyte‐gated organic transistor, is the prototype of a new generation of low‐power hybrid bio‐optoelectronic organic devices. [ABSTRACT FROM AUTHOR]

In this paper a novel approach is presented to prepare flexible and transparent conducting films, whose components can be separated and recovered via a recycling process. The fabrication method is based on low power sputtering of ultrathin gold layers on sodium alginate free‐standing films. The resulting foils are thin, easy to handle, and shape, while showing good conductive properties. In particular, they show excellent resistance to mechanical stress, like bending or rubbing, and are highly stable in ambient atmosphere over several months. Therefore they may represent a very promising candidate to be employed in green electronics, thanks to the reduced energy consumption required for their fabrication, the absence of toxic components or chemicals that are derived from oil, and the possibility to disassemble the devices at the end of their life in environmentally friendly conditions. [ABSTRACT FROM AUTHOR]