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Sustained attention is a fundamental cognitive ability that influences various aspects of human functioning. Studies of the neural correlates of attention commonly treat sustained attention as an isolated construct, however in any ecological context, sustained attention interacts with other executive functions such as inhibition of interference and processing of complex hierarchical stimuli. We have thus constructed a protocol to probe the interplay between these cognitive processes during visual attention task. We contrast putative typical vs atypical attention by comparing 18 healthy participants with 53 adults with Attention-Deficit/Hyperactivity Disorder, for whom difficulties with sustained attention are a core symptom and thus constitute a natural experiment condition. Our behavioural and brain-imaging analyses demonstrate distinct neural patterns in bottom-up visual processing and attention allocation mechanisms in ADHD and Control groups, highlighting different cognitive strategies utilised by adults with ADHD and healthy participants in tasks requiring sustained attention.

Introduction: Setting the right price is crucial for effectively positioning products in the market. Conversely, setting a "non-optimal price"—one that is perceived as much lower or higher than the product's true market value—can negatively influence consumer decisions and business results. Methods: We conducted two electroencephalography (EEG) studies and one magnetoencephalography (MEG) study to investigate brain mechanisms underlying the perception of prices during a price judgment task. In each trial, participants were exposed to a mobile phone image (iPhone, Nokia, or Xiaomi) followed by a price, and instructed to judge whether the price was high or low based on a target word ("cheap" or "expensive"). Results: In both EEG experiments, we found a strong N400-like response to the incongruent target words following prices that substantially differed from the real market value of the mobile phone. The MEG experiment extended these findings by localizing the brain source of the price-related, M400-like response, the magnetic counterpart to the N400 component, in the ventromedial prefrontal cortex (vmPFC) and anterior cingulate cortex (ACC) implicated in value-based and reward-based learning, respectively. Our results demonstrate that both the brain sources and the timing of the price-related M400 response differed from those of the standard M400 evoked by semantically incongruent words. Discussion: Overall, our results suggest that the N400-like response can serve as a neural marker of price-product incongruity, with potential applications in consumer research. [ABSTRACT FROM AUTHOR]

Despite the extensive history of investigation, characterization and diagnostics of giftedness is still a point of debate. The lack of understanding of the phenomenon affects the identification process of gifted children, development of targeted educational programs and state of research in the field of gifted education. In the current systematic review, we seek to delineate the specific aspects in which gifted children differ from their typically developing peers in cognitive abilities, psychophysiology and psychological characteristics. Secondly, we aim to document the prevalence and criteria of intelligence tests used to assess gifted children and adolescents. We reviewed 104 articles from more than 25 countries that examined a total of 77,705 children ages 5–18 years. Results reveal a discernible trend toward adopting more culturally appropriate measures for assessing giftedness in children. Findings highlight that gifted children generally outperform their peers in several cognitive domains such as verbal working memory, inhibition, geometric problem solving, attention-switching and elemental information processing, showcasing an accuracy-reaction time trade-off. Psychophysiological assessments demonstrate heightened and accelerated brain activity during complex effortful cognitive processes. Psychological and behavioral measures reveal that gifted children score higher on tests measuring intrinsic motivation, self-efficacy, and openness to experience; as well as achieving higher grades in school and employing better problem-solving strategies. Our systematic review can be beneficial in educational and research contexts, giving directions in assessment of giftedness and designing future research. [ABSTRACT FROM AUTHOR]

Several clades of luminescent bacteria are known currently. They all contain similar lux operons, which include the genes luxA and luxB encoding a heterodimeric luciferase. The aldehyde oxygenation reaction is presumed to be catalyzed primarily by the subunit LuxA, whereas LuxB is required for efficiency and stability of the complex. Recently, genomic analysis identified a subset of bacterial species with rearranged lux operons lacking luxB. Here, we show that the product of the luxA gene from the reduced luxACDE operon of Enhygromyxa salina is luminescent upon addition of aldehydes both in vivo in Escherichia coli and in vitro. Overall, EsLuxA is much less bright compared with luciferases from Aliivibrio fischeri (AfLuxAB) and Photorhabdus luminescens (PlLuxAB), and most active with medium‐chain C4–C9 aldehydes. Crystal structure of EsLuxA determined at the resolution of 2.71 Å reveals a (β/α)8 TIM‐barrel fold, characteristic for other bacterial luciferases, and the protein preferentially forms a dimer in solution. The mobile loop residues 264–293, which form a β‐hairpin or a coil in Vibrio harveyi LuxA, form α‐helices in EsLuxA. Phylogenetic analysis shows EsLuxA and related proteins may be bacterial protoluciferases that arose prior to duplication of the luxA gene and its speciation to luxA and luxB in the previously described luminescent bacteria. Our work paves the way for the development of new bacterial luciferases that have an advantage of being encoded by a single gene. [ABSTRACT FROM AUTHOR]

Recent advances in machine learning techniques have led to development of a number of protein design and engineering approaches. One of them, ProteinMPNN, predicts an amino acid sequence that would fold and match user‐defined backbone structure. Its performance was previously tested for proteins composed of standard amino acids, as well as for peptide‐ and protein‐binding proteins. In this short report, we test whether ProteinMPNN can be used to reengineer a non‐proteinaceous ligand‐binding protein, flavin‐based fluorescent protein CagFbFP. We fixed the native backbone conformation and the identity of 20 amino acids interacting with the chromophore (flavin mononucleotide, FMN) while letting ProteinMPNN predict the rest of the sequence. The software package suggested replacing 36–48 out of the remaining 86 amino acids so that the resulting sequences are 55%–66% identical to the original one. The three designs that we tested experimentally displayed different expression levels, yet all were able to bind FMN and displayed fluorescence, thermal stability, and other properties similar to those of CagFbFP. Our results demonstrate that ProteinMPNN can be used to generate diverging unnatural variants of fluorescent proteins, and, more generally, to reengineer proteins without losing their ligand‐binding capabilities. [ABSTRACT FROM AUTHOR]

Flavins such as flavin mononucleotide or flavin adenine dinucleotide are bound by diverse proteins, yet have very similar spectra when in the oxidized state. Recently, we developed new variants of flavin‐binding protein CagFbFP exhibiting notable blue (Q148V) or red (I52V A85Q) shifts of fluorescence emission maxima. Here, we use time‐resolved and low‐temperature spectroscopy to show that whereas the chromophore environment is static in Q148V, an additional protein‐flavin hydrogen bond is formed upon photoexcitation in the I52V A85Q variant. Consequently, in Q148V, excitation, emission, and phosphorescence spectra are shifted, whereas in I52V A85Q, excitation and low‐temperature phosphorescence spectra are relatively unchanged, while emission spectrum is altered. We also determine the x‐ray structures of the two variants to reveal the flavin environment and complement the spectroscopy data. Our findings illustrate two distinct color‐tuning mechanisms of flavin‐binding proteins and could be helpful for the engineering of new variants with improved optical properties. [ABSTRACT FROM AUTHOR]

This article argues that the institutional practices and journalistic ethics on RT, formerly Russia Today, have been influenced by the Soviet kontrpropaganda tradition, a defence mechanism against anti-communist narratives. RT's post-Soviet institutional structure has enabled the continuation of inherently 'defensive' practices in a way that they form a 'countering' ethic on the network. While kontrpropaganda informs the journalistic culture of RT's Russian staff, its international journalists are socialised into it. This article uses historical texts, archival materials and interviews with current and former journalists of RT and the Rossiya Segodnya network to examine how these defensive practices have become an everyday norm. In their strive for broadening the audience and for changing public opinion in the West, RT's staff adopts reactive, patriotic or legitimising practices. The countering ethic on RT informs the journalists' scramble for legitimacy not only of Russia as a country but also of RT as their employer. By analysing the underpinnings that organise the work of RT journalists, the article sheds light on broader problems of countering as a status-seeking effort in the international media ecosystem and contributes to ongoing research on self-censorship and conspiracy theories. [ABSTRACT FROM AUTHOR]

Previous research highlighted how algorithms on social media platforms can be abused to disseminate disinformation. However, less work has been devoted to understanding the interplay between Facebook news curation mechanisms and propaganda content. To address this gap, we analyze the activities of RT (formerly, Russia Today) on Facebook during the 2020 U.S. presidential election. We use agent-based algorithmic auditing and frame analysis to examine what content RT published on Facebook and how it was algorithmically curated in Facebook News Feeds and Search Results. We find that RT's strategic framing included the promotion of anti-Biden leaning content, with an emphasis on antiestablishment narratives. However, due to algorithmic factors on Facebook, individual agents were exposed to eclectic RT content without an overarching narrative. Our findings contribute to the debate on computational propaganda by highlighting the ambiguous relationship between government-sponsored media and Facebook algorithmic curation, which may decrease the exposure of users to propaganda and at the same time increase confusion. [ABSTRACT FROM AUTHOR]