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Pericardial edema is commonly observed in zebrafish embryo-based chemical toxicity screens, and a mechanism underlying edema may be disruption of embryonic osmoregulation. Therefore, the objective of this study was to identify whether triphenyl phosphate (TPHP) - a widely used aryl phosphate ester-based flame retardant - induces pericardial edema via impacts on osmoregulation within embryonic zebrafish. In addition to an increase in TPHP-induced microridges in the embryonic yolk sac epithelium, an increase in ionic strength of exposure media exacerbated TPHP-induced pericardial edema when embryos were exposed from 24 to 72 h post-fertilization (hpf). However, there was no difference in embryonic sodium concentrations in situ within TPHP-exposed embryos relative to embryos exposed to vehicle (0.1% DMSO) from 24 to 72 hpf. Interestingly, increasing the osmolarity of exposure media with mannitol (an osmotic diuretic which mitigates TPHP-induced pericardial edema) and increasing the ionic strength of the exposure media (which exacerbates TPHP-induced pericardial edema) did not affect embryonic doses of TPHP, suggesting that TPHP uptake was not altered under these varying experimental conditions. Overall, our findings suggest that TPHP-induced pericardial edema within zebrafish embryos is dependent on the ionic strength of exposure media, underscoring the importance of further standardization of exposure media and embryo rearing protocols in zebrafish-based chemical toxicity screening assays.

Abstract Background The COVID‐19 pandemic, caused by the SARS‐CoV‐2 virus, has resulted in illness, deaths and societal disruption on a global scale. Societies have implemented various control measures to reduce transmission of the virus and mitigate its impact. Individual behavioural changes are crucial to the successful implementation of these measures. One commonly recommended measure to limit risk of infection is frequent handwashing. It is important to identify those factors that can predict the uptake and maintenance of handwashing. Objectives We aimed to identify and synthesise the evidence on malleable psychological and psychosocial factors that determine uptake and adherence to handwashing aimed at reducing the risk of infection or transmission of COVID‐19. Search Methods We searched various literature sources including electronic databases (Medline ALL, Child Development & Adolescent Studies, ERIC, PsycInfo, CINAHL and Web of Science), web searches, conference proceedings, government reports, other repositories of literature and grey literature. The search strategy was built around three concepts of interest including (1) context (terms relating to COVID‐19), (2) behaviour of interest and (3) terms related to psychological and psychosocial determinants of COVID Health‐Related Behaviours and adherence or compliance with handwashing, to capture malleable determines. Searches capture studies up until October 2021. Selection Criteria Eligibility criteria included observational studies (both retrospective and prospective) and experimental studies that measure and report malleable psychological and psychosocial determinants and handwashing at an individual level, amongst the general public. Screening was supported by the Cochrane Crowd. Titles and abstracts were screened against the eligibility criteria by three independent screeners. Following this, all potentially relevant studies were screened at full‐text level by the research team. All conflicts between screeners were resolved by discussion between the core research team. Data Collection and Analysis All data extraction was managed in EPPI‐Reviewer software. All eligible studies, identified through full‐text screening were extracted by one author. We extracted data on study information, population, determinant, behaviour and effects. A second author checked data extraction on 20% of all included papers. All conflicts were discussed by the two authors until consensus was reached. We assessed methodological quality of all included studies using an adapted version of the Joanna Briggs Institute Quality appraisal tool for cross‐sectional studies. Main Results Our initial searches yielded 23,587 results, of which 56 studies were included in this review. The included studies were cross sectional in design, came from 22 countries and had a combined sample of 199,376 participants. The vast majority of studies had samples from the general public, with eight of the studies focusing on specific samples. All included studies considered people over the age of 18. The quality of the majority of the studies was good (n = 30 rated low risk of bias), with 8 rated high risk of bias, predominately due to lack of reporting of recruitment, sample characteristics and methodology. Thirty‐four studies were included in the narrative synthesis and 28 in the meta‐analysis. Findings indicated that emotions about COVID‐19 (worry [0.381, confidence interval [CI] = 0.270–0.482, I2 = 92%) and anxiety (0.308, CI = 0.154–0.448, I2 = 91%]), knowledge of COVID‐19 (0.323, CI = 0.223–0.417, I2 = 94%), and perceived social norms (0.303, CI = 0.184–0.413, I2 = 92%) were among the malleable determinants most associated with handwashing. Perceived severity (0.006, CI = ‐0.011–0.023) and susceptibility of COVID‐19 (0.041, CI = −0.034 to 0.115) had little to no effect on handwashing behaviour. Authors' Conclusions Understanding the effects of various malleable determinants on COVID‐related handwashing can aid in the development and implementation of interventions and public health campaigns to promote handwashing behaviour in potential new waves of COVID‐19 or other respiratory infections. Emotions about COVID, knowledge of COVID and perceived social norms warrant further consideration in future research and policy.

Abstract Background The COVID‐19 pandemic, caused by the SARS‐CoV‐2 virus, has resulted in illness, deaths and societal disruption on a global scale. Societies have implemented various control measures to reduce transmission of the virus and mitigate its impact. Individual behavioural changes are crucial to the successful implementation of these measures. One commonly recommended measure to limit risk of infection is face covering. It is important to identify those factors that can predict the uptake and maintenance of face covering. Objectives We aimed to identify and synthesise the evidence on malleable psychological and psychosocial factors that determine uptake and adherence to face covering aimed at reducing the risk of infection or transmission of COVID‐19. Search Methods We searched various literature sources including electronic databases (Medline ALL, Child Development & Adolescent Studies, ERIC, PsycInfo, CINAHL & Web of Science), web searches, conference proceedings, government reports, other repositories of literature and grey literature. The search strategy was built around three concepts of interest including (1) context (terms relating to COVID19), (2) behaviour of interest and (3) terms related to psychological and psychosocial determinants of COVID Health‐Related Behaviours and adherence or compliance with face covering, to capture malleable determines. Searches capture studies up until October 2021. Selection Criteria Eligibility criteria included observational studies (both retrospective and prospective) and experimental studies that measure and report malleable psychological and psychosocial determinants and handwashing at an individual level, amongst the general public. Screening was supported by the Cochrane Crowd. Studies titles and abstracts were screened against the eligibility criteria by three independent screeners. Following this, all potentially relevant studies were screened at full‐text level by the research team. All conflicts between screeners were resolved by discussion between the core research team. Data Collection and Analysis All data extraction was managed in EPPI‐Reviewer software. All eligible studies, identified through full‐text screening were extracted by one author. We extracted data on study information, population, determinant, behaviour and effects. A second author checked data extraction on 20% of all included papers. All conflicts were discussed by the two authors until consensus was reached. We assessed methodological quality of all included studies using an adapted version of the Joanna Briggs Institute Quality appraisal tool for cross‐sectional studies. Main Results Our initial searches yielded 23,587 results, of which 23 were included in this review. The included studies were cross‐sectional in design, came from nine countries and had a combined sample of 54,401 participants. The vast majority of studies had samples from the general public, with five of the studies focusing on specific samples. All included studies considered people over the age of 18. The quality of 10 of the studies was rated as unclear, 10 were rated as low, and 3 rated high risk of bias, predominately due to lack of reporting of recruitment, sample characteristics and methodology. Ten studies were included in the meta‐analysis and 16 in the narrative synthesis. Findings from the meta‐analysis indicated that knowledge of COVID‐19 (0.341, 95% confidence interval [CI] = 0.06, 0.530, I2 = 100%) was the malleable determinant most associated with face covering behaviour. Perceived susceptibility of COVID‐19 (r = 0.088, 95% CI = −0.004, 0.180, I2 = 80%) and COVID‐related worry and anxiety (r = 0.064, 95% CI = −0.066, 0.191, I2 = 93% had little to no effect on face covering behaviour. In the narrative synthesis, the strongest association was found between perceived benefits and effectiveness of behaviours and mask wearing behaviour. Authors' Conclusions Understanding the effects of various malleable determinants on COVID‐related face covering can aid in the development and implementation of interventions and public health campaigns to promote face covering behaviour in potential new waves of COVID‐19 or other respiratory infections. Knowledge of COVID and perceived benefits of face coverings warrant further consideration in future research and policy.

Abstract 2D materials have received a lot of interest over the past decade. Especially van der Waals (vdW) 2D materials, such as transition metal dichalcogenides (TMDCs), and their heterostructures exhibit semiconducting properties that make them highly suitable for novel device applications. Controllable mixing and matching of the 2D materials with different properties and precise control of the in‐plane twist angle in these heterostructures are essential to achieve superior properties and need to be established through large‐scale device fabrication. To gain fundamental insight into the potential control of these twist angles, 2D heterostructures of tungsten disulfide (WS2) and graphene (Gr) grown by bottom‐up synthesis via metal‐organic chemical vapor deposition (MOCVD) are investigated using a scanning transmission electron microscope (STEM). Specifically, the combination of conventional high‐resolution imaging with scanning nanobeam diffraction (SNBD) using advanced 4D STEM techniques is used to analyze moiré structures. The latter technique is used to reveal the epitaxial alignment within the WS2/Gr heterostructure, showing a direct influence of the underlying Gr layers on the moiré structure in the subsequent WS2 layers. In particular, the importance of grain boundaries (GBs) within the underlying WS2 and Gr layers on the structure of moiré patterns with rotation angles below 2° is discussed.

Background Large-scale sequencing of SARS-CoV-2 has enabled the study of viral evolution during the COVID-19 pandemic. Some viral mutations may be advantageous to viral replication within hosts but detrimental to transmission, thus carrying a transient fitness advantage. By affecting the number of descendants, persistence times and growth rates of associated clades, these mutations generate localised imbalance in phylogenies. Quantifying these features in closely-related clades with and without recurring mutations can elucidate the tradeoffs between within-host replication and between-host transmission. Methods We implemented a novel phylogenetic clustering algorithm (mlscluster, https://github.com/mrc-ide/mlscluster) to systematically explore time-scaled phylogenies for mutations under transient/multilevel selection. We applied this method to a SARS-CoV-2 time-calibrated phylogeny with >1.2 million sequences from England, and characterised these recurrent mutations that may influence transmission fitness across PANGO-lineages and genomic regions using Poisson regressions and summary statistics. Results We found no major differences across two epidemic stages (before and after Omicron), PANGO-lineages, and genomic regions. However, spike, nucleocapsid, and ORF3a were proportionally more enriched for transmission fitness polymorphisms (TFP)-homoplasies than other proteins. We provide a catalog of SARS-CoV-2 sites under multilevel selection, which can guide experimental investigations within and beyond the spike protein. Conclusions This study provides empirical evidence for the existence of important tradeoffs between within-host replication and between-host transmission shaping the fitness landscape of SARS-CoV-2. This method may be used as a fast and scalable means to shortlist large sequence databases for sites under putative multilevel selection which may warrant subsequent confirmatory analyses and experimental confirmation.

ABSTRACT Objective: We aimed to analyze the frequency of adherence to social distancing and individual protection measures of adult and older populations in two cities in southern Brazil and to characterize the sociodemographic aspects of these individuals. Methods: This cross-sectional, population-based study was conducted in the cities of Rio Grande, RS, and Criciúma, SC, Brazil. The outcome measure was the frequency of adherence to social distancing measures. Fisher's exact test (5% significance) was used to calculate the differences in prevalence according to exposure variables. Results: Among the 2,170 participants over the age of 18, the prevalence of adherence to social distancing was 18.5%. Adherence was significantly higher among women; older adults; single, divorced, or widowed people with a low educational level; people of lower socioeconomic status; and people affected by multiple chronic diseases. Conclusion: Approximately one in five respondents adhered to measures of social distancing, and adherence was more prevalent among the risk groups.

The SARS-CoV-2 Delta (Pango lineage B.1.617.2) variant of concern spread globally, causing resurgences of COVID-19 worldwide1,2. The emergence of the Delta variant in the UK occurred on the background of a heterogeneous landscape of immunity and relaxation of non-pharmaceutical interventions. Here we analyse 52,992 SARS-CoV-2 genomes from England together with 93,649 genomes from the rest of the world to reconstruct the emergence of Delta and quantify its introduction to and regional dissemination across England in the context of changing travel and social restrictions. Using analysis of human movement, contact tracing and virus genomic data, we find that the geographic focus of the expansion of Delta shifted from India to a more global pattern in early May 2021. In England, Delta lineages were introduced more than 1,000 times and spread nationally as non-pharmaceutical interventions were relaxed. We find that hotel quarantine for travellers reduced onward transmission from importations; however, the transmission chains that later dominated the Delta wave in England were seeded before travel restrictions were introduced. Increasing inter-regional travel within England drove the nationwide dissemination of Delta, with some cities receiving more than 2,000 observable lineage introductions from elsewhere. Subsequently, increased levels of local population mixing-and not the number of importations-were associated with the faster relative spread of Delta. The invasion dynamics of Delta depended on spatial heterogeneity in contact patterns, and our findings will inform optimal spatial interventions to reduce the transmission of current and future variants of concern, such as Omicron (Pango lineage B.1.1.529).

Abstract Rydberg excitons in Cu2O feature giant optical nonlinearities. To exploit these nonlinearities for quantum applications, the confinement must match the Rydberg blockade size, which in Cu2O could be as large as a few microns. Here, in a top-down approach, we show how exciton confinement can be realised by focused-ion-beam etching of a polished bulk Cu2O crystal without noticeable degradation of the excitonic properties. The etching of the crystal to micron sizes allows for tuning the energies of Rydberg excitons locally, and precisely, by optically induced temperature change. These results pave the way for exploiting the large nonlinearities of Rydberg excitons in micropillars for making non-classical light sources, while the precise tuning of their emission energy opens up a viable pathway for realising a scalable photonic quantum simulation platform.

Abstract In response to the COVID-19 pandemic, multiple vaccines were developed using platforms such as viral vectors and mRNA technology. Here, we report humoral and cellular immunogenicity data from human phase 1 clinical trials investigating two recombinant Modified Vaccinia virus Ankara vaccine candidates, MVA-SARS-2-S and MVA-SARS-2-ST, encoding the native and the prefusion-stabilized SARS-CoV-2 spike protein, respectively. MVA-SARS-2-ST was more immunogenic than MVA-SARS-2-S, but both were less immunogenic compared to licensed mRNA- and ChAd-based vaccines in SARS-CoV-2 naïve individuals. In heterologous vaccination, previous MVA-SARS-2-S vaccination enhanced T cell functionality and MVA-SARS-2-ST boosted the frequency of T cells and S1-specific IgG levels when used as a third vaccination. While the vaccine candidate containing the prefusion-stabilized spike elicited predominantly S1-specific responses, immunity to the candidate with the native spike was skewed towards S2-specific responses. These data demonstrate how the spike antigen conformation, using the same viral vector, directly affects vaccine immunogenicity in humans.

Abstract We report the precise measurement of electric fields in nanostructures, and high-contrast imaging of soft matter at ultralow electron doses by transmission electron microscopy (TEM). In particular, a versatile method based on the theorem of reciprocity is introduced to enable differential phase contrast imaging and ptychography in conventional, plane-wave illumination TEM. This is realised by a series of TEM images acquired under different tilts, thereby introducing the sampling rate in reciprocal space as a tuneable parameter, in contrast to momentum-resolved scanning techniques. First, the electric field of a p–n junction in GaAs is imaged. Second, low-dose, in-focus ptychographic and DPC characterisation of Kagome pores in weakly scattering covalent organic frameworks is demonstrated by using a precessing electron beam in combination with a direct electron detector. The approach offers utmost flexibility to record relevant spatial frequencies selectively, while acquisition times and dose requirements are significantly reduced compared to the 4D-STEM counterpart.

The decisive experimental evidence of enhanced heat conduction driven by surface phonon polaritons (SPhPs) has been recently demonstrated along polar nanofilms. However, a proper quantitative interpretation remains to be fully established. In this work, we provide a consistent theoretical explanation of the measured thermal conductivities of polar nanofilms, based on a coupled Boltzmann transport equation and heat diffusion equation for describing the dynamics of SPhPs and phonons, respectively. This formalism enables to separately quantify the SPhP and phonon contributions to the in-plane heat transport and shows the overestimation of the SPhP thermal conductivity predicted by previous empirical model for predominant boundary scattering. This study, thus, promotes the understanding of the observed thermal conductivity enhancement driven by SPhPs, as a novel heat conduction channel for heat dissipation applications in nanoelectronics and optoelectronics. [ABSTRACT FROM AUTHOR]

Tris (1,3-dichloro-2-propyl) phosphate (TDCIPP) is an organophosphate ester-based flame retardant widely used within the United States. Within zebrafish, initiation of TDCIPP exposure at 0.75 h post-fertilization (hpf) reliably disrupts cytosine methylation from cleavage (2 hpf) through early-gastrulation (6 hpf). Therefore, the objective of this study was to determine whether TDCIPP-induced effects on cytosine methylation persist beyond 6 hpf. First, we exposed embryos to vehicle or TDCIPP from 0.75 hpf to 6, 24, or 48 hpf, and then conducted bisulfite amplicon sequencing of a target locus (lmo7b) using genomic DNA derived from whole embryos. Within both vehicle- and TDCIPP-treated embryos, CpG methylation was similar at 6 hpf and CHG/CHH methylation were similar at 24 and 48 hpf (relative to 6 hpf). However, relative to 6 hpf within the same treatment, CpG methylation was lower within vehicle-treated embryos at 48 hpf and TDCIPP-treated embryos at 24 and 48 hpf - an effect that was driven by acceleration of CpG hypomethylation. Similar to our previous findings with DNA methyltransferase, we found that, even at high μM concentrations, TDCIPP had no effect on zebrafish and human thymine DNA glycosylase activity (a key enzyme that decreases CpG methylation), suggesting that TDCIPP-induced effects on CpG methylation are not driven by direct interaction with thymine DNA glycosylase. Finally, using 5-methylcytosine (5-mC)-specific whole-mount immunochemistry and automated imaging, we found that exposure to TDCIPP increased 5-mC abundance within the yolk of blastula-stage embryos, suggesting that TDCIPP may impact cytosine methylation of maternally loaded mRNAs during the maternal-to-zygotic transition. Overall, our findings suggest that TDCIPP disrupts the trajectory of cytosine methylation during zebrafish embryogenesis, effects which do not appear to be driven by direct interaction of TDCIPP with key enzymes that regulate cytosine methylation.