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Genomes are constantly in flux, undergoing changes due to recombination, repair and mutagenesis. In vivo, many of such changes are studies using reporters for specific types of changes, or through cytological studies that detect changes at the single-cell level. Single molecule assays, which are reviewed here, can detect transient intermediates and dynamics of events. Biochemical assays allow detailed investigation of the DNA and protein activities of each step in a repair, recombination or mutagenesis event. Each type of assay is a powerful tool but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.

Pupil size is a non‐invasive index for autonomic arousal mediated by the locus coeruleus–norepinephrine (LC‐NE) system. While pupil size and its derivative (velocity) are increasingly used as indicators of arousal, limited research has investigated the relationships between pupil size and other well‐known autonomic responses. Here, we simultaneously recorded pupillometry, heart rate, skin conductance, pulse wave amplitude, and respiration signals during an emotional face–word Stroop task, in which task‐evoked (phasic) pupil dilation correlates with LC‐NE responsivity. We hypothesized that emotional conflict and valence would affect pupil and other autonomic responses, and trial‐by‐trial correlations between pupil and other autonomic responses would be observed during both tonic and phasic epochs. Larger pupil dilations, higher pupil size derivative, and lower heart rates were observed in the incongruent condition compared to the congruent condition. Additionally, following incongruent trials, the congruency effect was reduced, and arousal levels indexed by previous‐trial pupil dilation were correlated with subsequent reaction times. Furthermore, linear mixed models revealed that larger pupil dilations correlated with higher heart rates, higher skin conductance responses, higher respiration amplitudes, and lower pulse wave amplitudes on a trial‐by‐trial basis. Similar effects were seen between positive and negative valence conditions. Moreover, tonic pupil size before stimulus presentation significantly correlated with all other tonic autonomic responses, whereas tonic pupil size derivative correlated with heart rates and skin conductance responses. These results demonstrate a trial‐by‐trial relationship between pupil dynamics and other autonomic responses, highlighting pupil size as an effective real‐time index for autonomic arousal during emotional conflict and valence processing. [ABSTRACT FROM AUTHOR]

Autistic individuals encounter challenges in recognizing emotional expressions of others. Pupillary response has been proposed as an indicator of arousal dysregulation or cognitive load. The pupillary response of autistic individuals during socio‐affective tasks remains unclear. This study investigated pupillary response in autistic adults when viewing emotional faces/eyes and recognizing emotions during the Reading the Mind in the Eyes Test (RMET) and watching interpersonal touch scenes in the social touch task. The study included 98 participants diagnosed with autism spectrum disorder and 37 typically developing controls (TD). Pupil size was measured using the Tobii X2‐30 Eye Tracker. The results showed that autistic adults had larger maximal pupil sizes, smaller minimal pupil sizes, and greater change rates of pupil size, particularly during the RMET Eyes task. Clinical correlations revealed that attention switching difficulty positively correlated with mean pupil size in TD participants, while social communication deficits positively correlated with mean pupil size in autistic participants. In conclusion, our findings suggest atypical pupillary responses in autistic adults during socio‐affective tasks, indicating heightened cognitive demand. Further investigation is necessary to understand the underlying mechanisms and their association with autistic traits. Lay Summary: Autistic adults show unusual changes in their pupils when they read other people's facial emotions. Their pupils change size more to reach larger maximal sizes, and change size more quickly, suggesting it takes more mental effort for them to read emotions on faces. The average pupil size during the task may be linked to autistic traits. In non‐autistic people, larger pupils were related to difficulty switching attention; while in autistic adults, larger pupils were related to difficulty in social communication. [ABSTRACT FROM AUTHOR]

The locus coeruleus‐norepinephrine (LC‐NE) system, which regulates arousal levels, is important for cognitive control, including emotional conflict resolution. Additionally, the LC‐NE system is implicated in P300 generation. If the P300 is mediated by the LC‐NE system, and considering the established correlations between LC activity and pupil dilation, P300 amplitude should correlate with task‐evoked (phasic) pupil dilation on a trial‐by‐trial basis. However, prior studies, predominantly utilizing oddball‐type paradigms, have not demonstrated correlations between concurrently recorded task‐evoked pupil dilation and P300 responses. Using a recently developed emotional face‐word Stroop task that links pupil dilation to the LC‐NE system, here, we examined both intra‐ and inter‐individual correlations between task‐evoked pupil dilation and P300 amplitude. We found that lower accuracy, slower reaction times, and larger task‐evoked pupil dilation were obtained in the incongruent compared to the congruent condition. Furthermore, we observed intra‐individual correlations between task‐evoked pupil dilation and P300 amplitude, with larger pupil dilation correlating with a greater P300 amplitude. In contrast, pupil dilation did not exhibit consistent correlations with N450 and N170 amplitudes. Baseline (tonic) pupil size also showed correlations with P300 and N170 amplitudes, with smaller pupil size corresponding to larger amplitude. Moreover, inter‐individual differences in task‐evoked pupil dilation between the congruent and incongruent conditions correlated with differences in reaction time and P300 amplitude, though these effects only approached significance. To summarize, our study provides evidence for a connection between task‐evoked pupil dilation and P300 amplitude at the single‐trial level, suggesting the involvement of the LC‐NE system in P300 generation. The locus coeruleus‐norepinephrine system is implicated in the generation of the P300. Using pupillometry as an indirect measure of locus coeruleus‐norepinephrine activity, we demonstrated intra‐individual trial‐to‐trial correlations between concurrently recorded task‐evoked pupil dilation and P300 responses in the emotional face‐word Stroop task, with larger pupil dilation correlating with a greater P300 amplitude, suggesting the involvement of the locus coeruleus‐norepinephrine system in P300 generation. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting is a key technology for long-term hydrogen evolution with low environmental impact. In this work, an environment-friendly photocatalyst consisting of FeS2–TiO2 heterostructured nanocrystals has been successfully prepared by wet chemical synthesis for enhancing the photocatalytic hydrogen production rate over a wide range of absorption wavelengths. Its absorption range has been extended from the ultraviolet–visible to near-infrared (NIR) spectrum. The results of ultrafast optical spectroscopy suggest that charge transfer occurs between the FeS2 and TiO2 interface under NIR pulsed laser irradiation (800 nm). The highest photocatalytic hydrogen production rate of the FeS2–TiO2 heterostructure has been obtained in comparison with FeS2 nanocrystals (NCs) and TiO2 nanoparticles (NPs) under irradiation by a mercury arc lamp or a xenon lamp. In the FeS2–TiO2 heterostructure, the FeS2 NCs as a light harvester can efficiently absorb visible and NIR light to generate much more photoelectrons than TiO2 NPs only for hydrogen production. For long-term photocatalytic hydrogen production, the FeS2–TiO2 heterostructures also reveal an outstanding durability over 40 h. Overall, the FeS2–TiO2 heterostructure shows potential to be a TiO2-based photocatalyst for clean hydrogen production in practical applications. [ABSTRACT FROM AUTHOR]

Background: Influenza virus infection is a major threat to human health. Small interfering RNA (siRNA) is a promising approach for the prevention and treatment of viral infections. In this study, we constructed a series of DNA vector-based short hairpin RNAs (shRNAs) that target various genes of the influenza A virus using the polymerase III U6-RNA promoter to prevent influenza virus infection in vitro and in a mouse model. Results: Three sets of DNA vector-based shRNA, two targeting genes encoding the polymerase acidic protein (PA) and one targeting polymerase basic protein 2 (PB2), efficiently inhibited the replication of influenza virus A/WSN/33(H1N1) in vitro. We also successfully prevented influenza virus A/WSN/33(H1N1) infection in a C57BL/6 mouse model by intratracheal delivery of anti-PB2 shRNA. Conclusions: Our findings suggest that the PB2-targeting shRNA plasmid showed potential for use as an RNAi-based therapeutic for influenza virus infection. [ABSTRACT FROM AUTHOR]

The interaction between Phytophthora pathogens and host plants involves the exchange of complex molecular signals from both sides. Recent studies of Phytophthora have led to the identification of various apoplastic elicitors known to trigger plant immunity. Here, we provide evidence that the protein encoded by OPEL of Phytophthora parasitica is a novel elicitor. Homologues of OPEL were identified only in oomycetes, but not in fungi and other organisms. Quantitative reverse transcription-polymerase chain reaction ( RT-PCR) revealed that OPEL is expressed throughout the development of P. parasitica and is especially highly induced after plant infection. Infiltration of OPEL recombinant protein from Escherichia coli into leaves of Nicotiana tabacum (cv. Samsun NN) resulted in cell death, callose deposition, the production of reactive oxygen species and induced expression of pathogen-associated molecular pattern ( PAMP)-triggered immunity markers and salicylic acid-responsive defence genes. Moreover, the infiltration conferred systemic resistance against a broad spectrum of pathogens, including Tobacco mosaic virus, the bacteria wilt pathogen Ralstonia solanacearum and P. parasitica. In addition to the signal peptide, OPEL contains three conserved domains: a thaumatin-like domain, a glycine-rich protein domain and a glycosyl hydrolase ( GH) domain. Intriguingly, mutation of a putative laminarinase active site motif in the predicted GH domain abolished its elicitor activity, which suggests enzymatic activity of OPEL in triggering the defence response. [ABSTRACT FROM AUTHOR]

Pupil size primarily changes to regulate the amount of light entering the retina, optimizing the balance between visual acuity and sensitivity for effective visual processing. However, research directly examining the relationship between pupil size and visual processing has been limited. While a few studies have recorded pupil size and EEG signals to investigate the role of pupil size in visual processing, these studies have predominantly focused on the domain of visual sensitivity. Causal effects of pupil size on visual acuity, therefore, remain poorly understood. By manipulating peripheral background luminance levels and target stimulus contrast while simultaneously recording pupillometry and EEG signals, we examined how absolute pupil size affects visual discrimination and visually evoked potentials (VEP) in a task using optotype mimicking the Snellen eye chart, the most common assessment of visual acuity. Our findings indicate that both higher background luminance levels and higher target contrast were associated with improved target discrimination and faster correct reaction times. Moreover, while higher contrast visual stimuli evoked larger VEPs, the effects of pupil size on VEPs were not significant. Additionally, we did not observe inter-individual correlations between absolute pupil size and discrimination performance or VEP amplitude. Together, our results demonstrate that absolute pupil size, regulated by global luminance level, played a functional role in enhancing visual discrimination performance in an optotype discrimination task. The differential VEP effects of pupil size compared to those of stimulus contrast further suggested distinct neural mechanisms involved in facilitating visual acuity under small pupils., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chin, Tai, Yep, Chang, Hsu and Wang.)