Whole Genome Sequencing of SARS-CoV-2 in Cats and Dogs in South Korea in 2021.

SARS-CoV-2 infections have caused unprecedented damage worldwide by affecting humans and various animals. The first reported animal infection was observed in a pet dog in Hong Kong in March 2020. 36 countries reported 692 SARS-CoV-2 infections in 25 different animal species by 31 August 2022. Most outbreaks were caused by contact with SARS-CoV-2 infected humans. In South Korea, the first SARS-CoV-2 infection in an animal was reported in a cat in February 2021. As of 31 December 2021, 74 dogs and 42 cats have been confirmed to have SARS-CoV-2 in South Korea. Here, we identified various SARS-CoV-2 genomic lineages in SARS-CoV-2 confirmed cats and dogs. Among the 40 animal samples sequenced for lineage identification, a total of eight Pango lineages (B.1.1.7 (Alpha variant), B.1.429 (Epsilon variant), B.1.470, B.1.497, B.1.619.1, B.1.620, AY.69 (Delta variant), and AY.122.5 (Delta variant)) were identified. The dominant lineages were AY.69 (Delta variant; 37.5%), B.1.497 (35.0%), and B.1.619.1 (12.5%). This study provides the first reported cases of six lineages (B.1.470, B.1.497, B.1.620, B.1.619.1, AY.69 (Delta variant)), and AY.122.5 (Delta variant) in cats and dogs. Our results emphasize the importance of monitoring SARS-CoV-2 in pets because they are dynamic hosts of variant Pango lineages of SARS-CoV-2.

Publisher Correction: MAOA variants differ in oscillatory EEG & ECG activities in response to aggression-inducing stimuli.

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MAOA variants differ in oscillatory EEG & ECG activities in response to aggression-inducing stimuli.

Among the genetic variations in the monoamine oxidase A (MAOA) gene, upstream variable number tandem repeats (uVNTRs) of the promoter have been associated with individual differences in human physiology and aggressive behaviour. However, the evidence for a molecular or neural link between MAOA uVNTRs and aggression remains ambiguous. Additionally, the use of inconsistent promoter constructs in previous studies has added to the confusion. Therefore, it is necessary to demonstrate the genetic function of MAOA uVNTR and its effects on multiple aspects of aggression. Here, we identified three MAOA alleles in Koreans: the predominant 3.5R and 4.5R alleles, as well as the rare 2.5R allele. There was a minor difference in transcriptional efficiency between the 3.5R and 4.5R alleles, with the greatest value for the 2.5R allele, in contrast to existing research. Psychological indices of aggression did not differ among MAOA genotypes. However, our electroencephalogram and electrocardiogram results obtained under aggression-related stimulation revealed oscillatory changes as novel phenotypes that vary with the MAOA genotype. In particular, we observed prominent changes in frontal γ power and heart rate in 4.5R carriers of men. Our findings provide genetic insights into MAOA function and offer a neurobiological basis for various socio-emotional mechanisms in healthy individuals.

A novel supportive assessment for comprehensive aggression using EEG and ECG.

Aggression is a complex, ubiquitous phenomenon that impacts behavioral traits and psychological health. Assessing aggression is challenging because aggression constitutes multiple subtraits, such as anger, reactive aggression, and overt aggression. Conventional methods of assessing aggression are susceptible to bias because they mainly rely upon self-reports. Thus, more objective methods that provide a multifaceted understanding of aggression in individuals are required. Here, we propose a supportive method of assessing specific aggression subtraits in Koreans using electroencephalography (EEG) and electrocardiography (ECG). Our evaluations and statistical analyses revealed that EEG and ECG signals in subjects responding to video cues that induced aggression are associated with aggression subtraits. In particular, we identified spectral differences in EEG signals in response to stimuli with situation-dependent aggression. The α and ß signals of the Fp2 site (the right ventromedial prefrontal region) are highly associated with anger, reactive aggression, and overt aggression. Moreover, ECG signals are associated with anger and overt aggression. These results link neurobiological findings to psychological explanations of aggression and multiple aspects of human behavior. Our findings can potentially be applied to supportive assessment methods for psychological counseling or psychiatric diagnoses.

Gender Differences in Aggression-related Responses on EEG and ECG.

Gender differences in aggression viewed from an evolutionary and sociocultural perspective have traditionally explained why men engage in more direct and physical aggression, and women engage in more indirect and relational aggression. However, psychological and behavioral studies offer inconsistent support for this theory due to personal or social factors, and little is known about the gender-based neurobiological mechanisms of aggression. This study investigates gender differences in aggression through an analysis of electroencephalography (EEG) and electrocardiography (ECG) based neurobiological responses to commonly encountered stimuli, as well as psychological approaches in healthy Korean youth. Our results from self-reports indicate that overall aggression indices, including physical and reactive/overt aggression, were stronger in men. This agrees with the results of previous studies. Furthermore, our study reveals prominent gender-related patterns in γ signals from the right ventrolateral frontal cortex and changes in heart rate through stimulation by aggressive videos. In particular, gender differences in EEG and ECG responses were observed in response to different scenes, as simple aversion and situation-dependent aggression, respectively. In addition, we discovered decisive gender-distinct EEG signals during stimulation of the situation-dependent aggression regions within the right ventromedial prefrontal and ventrolateral frontal regions. Our findings provide evidence of a psychological propensity for aggression and neurobiological mechanisms of oscillation underlying gender differences in aggression. Further studies of oscillatory responses to aggression and provocation will expand the objective understanding of the different emotional worlds between men and women.

Mussel-Inspired Anchoring of Polymer Loops That Provide Superior Surface Lubrication and Antifouling Properties.

We describe robustly anchored triblock copolymers that adopt loop conformations on surfaces and endow them with unprecedented lubricating and antifouling properties. The triblocks have two end blocks with catechol-anchoring groups and a looping poly(ethylene oxide) (PEO) midblock. The loops mediate strong steric repulsion between two mica surfaces. When sheared at constant speeds of ∼2.5 µm/s, the surfaces exhibit an extremely low friction coefficient of ∼0.002-0.004 without any signs of damage up to pressures of ∼2-3 MPa that are close to most biological bearing systems. Moreover, the polymer loops enhance inhibition of cell adhesion and proliferation compared to polymers in the random coil or brush conformations. These results demonstrate that strongly anchored polymer loops are effective for high lubrication and low cell adhesion and represent a promising candidate for the development of specialized high-performance biomedical coatings.

Formation, Removal, and Reformation of Surface Coatings on Various Metal Oxide Surfaces Inspired by Mussel Adhesives.

Mussels survive by strongly attaching to a variety of different surfaces, primarily subsurface rocks composed of metal oxides, through the formation of coordinative interactions driven by protein-based catechol repeating units contained within their adhesive secretions. From a chemistry perspective, catechols are known to form strong and reversible complexes with metal ions or metal oxides, with the binding affinity being dependent on the nature of the metal ion. As a result, catechol binding with metal oxides is reversible and can be broken in the presence of a free metal ion with a higher stability constant. It is proposed to exploit this competitive exchange in the design of a new strategy for the formation, removal, and reformation of surface coatings and self-assembled monolayers (SAM) based on catechols as the adhesive unit. In this study, catechol-functionalized tri(ethylene oxide) (TEO) was synthesized as a removable and recoverable self-assembled monolayer (SAM) for use on oxides surfaces. Attachment and detachment of these catechol derivatives on a variety of surfaces was shown to be reversible and controllable by exploiting the high stability constant of catechol to soluble metal ions, such as Fe(III). This tunable assembly based on catechol binding to metal oxides represents a new concept for reformable coatings with applications in fields ranging from friction/wettability control to biomolecular sensing and antifouling.

Improved performance of protected catecholic polysiloxanes for bioinspired wet adhesion to surface oxides.

A facile synthetic strategy for introducing catecholic moieties into polymeric materials based on a readily available precursor (eugenol) and efficient chemistries [tris(pentafluorophenyl)borane-catalyzed silation and thiol-ene coupling] is reported. Silyl protection is shown to be critical for the oxidative stability of catecholic moieties during synthesis and processing, which allows functionalized polysiloxane derivatives to be fabricated into 3D microstructures as well as 2D patterned surfaces. Deprotection gives stable catechol surfaces whose adhesion to a variety of oxide surfaces can be precisely tuned by the level of catechol incorporation. The advantage of silyl protection for catechol-functionalized polysiloxanes is demonstrated and represents a promising and versatile new platform for underwater surface treatments.

Reactive, multifunctional polymer films through thermal cross-linking of orthogonal click groups.

The ability to produce robust and functional cross-linked materials from soluble and processable organic polymers is dependent upon facile chemistries for both reinforcing the structure through cross-linking and for subsequent decoration with active functional groups. Generally, covalent cross-linking of polymeric assemblies is brought about by the application of heat or light to generate highly reactive groups from stable precursors placed along the chains that undergo coupling or grafting reactions. Typically, these strategies suffer from a general lack of control of the cross-linking chemistry as well as the fleeting nature of the reactive species that precludes secondary chemistry. We have addressed both of these issues using orthogonal chemistries to effect both cross-linking and subsequent functionalization of polymer films by mild heating, which results in exacting control of the cross-link density as well as the density of the residual stable functional groups available for subsequent, stepwise functionalization. This methodology is exploited to develop a strategy for the independent and orthogonal triple-functionalization of cross-linked polymer thin-films through microcontact printing.

Real-space mapping of the strongly coupled plasmons of nanoparticle dimers.

We carried out the near-field optical imaging of isolated and dimerized gold nanocubes to directly investigate the strong coupling between two adjacent nanoparticles. The high-resolution (approximately 10 nm) local field maps (intensities and phases) of self-assembled nanocube dimers reveal antisymmetric plasmon modes that are starkly different from a simple superposition of two monomeric dipole plasmons, which is fully reproduced by the electrodynamics simulations. The result decisively proves that, for the closely spaced pair of nanoparticles (interparticle distance/particle size approximately 0.04), the strong Coulombic attraction between the charges at the interparticle gap dominates over the intraparticle charge oscillations, resulting in a hybridized dimer plasmon mode that is qualitatively different from those expected from a simple dipole-dipole coupling model.

Nanoparticle assembly on nanoplates.

By using dithiol linkage or biological interaction, Au nanoparticles are readily assembled on the single-crystalline Au nanoplates with well-defined geometries.

Optical nonlinearities of Au nanoparticles and Au/Ag coreshells.

Au nanoparticles exhibited both negative and positive nonlinear absorptions with ground-state plasmon bleaching and free-carrier absorption that could be origins of the saturable and reverse-saturable optical properties. Au/Ag coreshells displayed only positive nonlinear absorption and reverse-saturable optical properties as a function of excitation intensity at the edge of surface-plasmon resonance, which implies no ground-state plasmon bleaching and the existence of two-photon absorption.

Controlled synthesis and characterization of the enhanced local field of octahedral Au nanocrystals.

Octahedral Au nanocrystals with localized surface plasmon-assisted enhancing optical properties can be prepared in aqueous solution via the forced reduction of Au ions by ascorbic acid through the addition of NaOH.