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Conjugated polymers have sparked much interest as photocatalysts for hydrogen production. However, beyond basic considerations such as spectral absorption, the factors that dictate their photocatalytic activity are poorly understood. Here we investigate a series of linear conjugated polymers with external quantum efficiencies for hydrogen production between 0.4 and 11.6%. We monitor the generation of the photoactive species from femtoseconds to seconds after light absorption using transient spectroscopy and correlate their yield with the measured photocatalytic activity. Experiments coupled with modeling suggest that the localization of water around the polymer chain due to the incorporation of sulfone groups into an otherwise hydrophobic backbone is crucial for charge generation. Calculations of solution redox potentials and charge transfer free energies demonstrate that electron transfer from the sacrificial donor becomes thermodynamically favored as a result of the more polar local environment, leading to the production of long-lived electrons in these amphiphilic polymers. While inorganic semiconductors are well-studied for their solar-to-fuel energy conversion abilities, organic materials receive far less attention. Here, authors prepare linear conjugated polymers as H 2 evolution photocatalysts and rationalize photocatalytic activities with fundamental properties.

Data on the safety of COVID-19 vaccines in early pregnancy are limited. We conducted a national, population-based, matched cohort study assessing associations between COVID-19 vaccination and miscarriage prior to 20 weeks gestation and, separately, ectopic pregnancy. We identified women in Scotland vaccinated between 6 weeks preconception and 19 weeks 6 days gestation (for miscarriage; n = 18,780) or 2 weeks 6 days gestation (for ectopic; n = 10,570). Matched, unvaccinated women from the pre-pandemic and, separately, pandemic periods were used as controls. Here we show no association between vaccination and miscarriage (adjusted Odds Ratio [aOR], pre-pandemic controls = 1.02, 95% Confidence Interval [CI] = 0.96–1.09) or ectopic pregnancy (aOR = 1.13, 95% CI = 0.92–1.38). We undertook additional analyses examining confirmed SARS-CoV-2 infection as the exposure and similarly found no association with miscarriage or ectopic pregnancy. Our findings support current recommendations that vaccination remains the safest way for pregnant women to protect themselves and their babies from COVID-19. Data on the safety of COVD-19 vaccines in early pregnancy are limited. Here, the authors assess the rates of miscarriage and ectopic pregnancy following vaccination using electronic health record data from Scotland, and find no evidence of increased risks.

ObjectivesTo examine neonates in Scotland aged 0–27 days with SARS-CoV-2 infection confirmed by viral testing; the risk of confirmed neonatal infection by maternal and infant characteristics; and hospital admissions associated with confirmed neonatal infections.DesignPopulation-based cohort study.Setting and populationAll live births in Scotland, 1 March 2020–31 January 2022.ResultsThere were 141 neonates with confirmed SARS-CoV-2 infection over the study period, giving an overall infection rate of 153 per 100 000 live births (141/92 009, 0.15%). Among infants born to women with confirmed infection around the time of birth, the confirmed neonatal infection rate was 1812 per 100 000 live births (15/828, 1.8%). Two-thirds (92/141, 65.2%) of neonates with confirmed infection had an associated admission to neonatal or (more commonly) paediatric care. Six of these babies (6/92, 6.5%) were admitted to neonatal and/or paediatric intensive care; however, none of these six had COVID-19 recorded as their main diagnosis. There were no neonatal deaths among babies with confirmed infection.Implications and relevanceConfirmed neonatal SARS-CoV-2 infection was uncommon over the first 23 months of the pandemic in Scotland. Secular trends in the neonatal confirmed infection rate broadly followed those seen in the general population, although at a lower level. Maternal confirmed infection at birth was associated with an increased risk of neonatal confirmed infection. Two-thirds of neonates with confirmed infection had an associated admission to hospital, with resulting implications for the baby, family and services, although their outcomes were generally good. Ascertainment of confirmed infection depends on the extent of testing, and this is likely to have varied over time and between groups: the extent of unconfirmed infection is inevitably unknown.

ObjectiveTo investigate the incidence of confirmed SARS-CoV-2 infection in neonates (babies aged 0–27 days inclusive) born in Scotland and assess maternal/infant characteristics of cases and hospital admission rates.MethodsThis was a population-based cohort study from 1st March 2020 to 31st January 2022. Data on all pregnancies and resulting live births in Scotland were obtained from the ‘COVID-19 in Pregnancy in Scotland’ (COPS) study dataset. The COPS dataset contained linked information on results of community and in-hospital SARS-CoV-2 viral testing; hospital admissions (including to neonatal units, paediatric wards and paediatric/neonatal intensive care units) and deaths among neonates; and maternal information including SARS-CoV-2 status at delivery, age, ethnicity and Scottish Index of Multiple Deprivation (SIMD) quintile. An admission was considered temporally associated with a baby’s SARS-CoV-2 infection if their first positive viral test occurred during, or in the 7 days prior to, the admission.ResultsLinked data were available for 92009 (of total 92032) livebirths and 141 (of 142) neonates with confirmed infection, with an infection rate of 153/100,000 live births (0.15%). The overall trend in infection rate followed that of the general paediatric population, albeit at a much lower level (figure 1). The infection rate was higher for babies born to mothers who tested positive for SARS-CoV-2 at the time of delivery; 1.8% (15/828) of these babies tested positive at some point in the first 27 days of life. Ninety-two babies (92/141, 65.2%) had a hospital admission which was temporally associated with their positive test (table 1). Six of these babies (6/92, 6.5%) had an episode in paediatric/neonatal intensive care but COVID-19 was not recorded as the main diagnosis in any of these cases. No neonate with a positive SARS-CoV-2 test died.ConclusionThis is the first population-wide study of SARS-CoV-2 in neonates which considers both those in the community and those admitted to hospital. We found that, during the first 23 months of the COVID-19 pandemic, confirmed neonatal SARS-CoV-2 infection was uncommon. Though almost 2/3 of neonates with a positive test were admitted, outcomes were good and admission to intensive care were lower than previously reported.1 2 Continued surveillance is important to monitor the ongoing impact of SARS-CoV-2 on neonates as the pandemic evolves.ReferencesSwann, et al. BMJ 2020.Swann, et al. Paed Res 2022.Abstract 113 Figure 1[Image Omitted. See PDF.]

Organic based semiconductor materials offer emerging and sustainable solutions for solar energy conversion technologies and electronics. However, knowledge of their intrinsic (photo)physical properties and light-matter interactions is often limited, especially with respect to the frequency dependent dielectric properties on the relevant timescales of exciton separation and charge generation (fs-ps). By using terahertz-time-domain spectroscopy (THz-TDS), we show that the complex permittivity and THz conductivity of different polymer materials and graphitic carbon nitrides - melon and poly(heptazine imides) (K-PHI) - can be measured directly and accurately in different environmental humidities. Its effects are most strongly observed in the ionic and 2D carbon nitride, K-PHI, where both real permittivity and THz conductivity double from dry to humid conditions (~4-8 and 75-150 S/m, respectively) surpassing the intrinsic dielectric response from water or K-PHI through synergistic effects. Our findings are backed by fs-ps transient absorption spectroscopy (TAS), confirming the impact of humidity on light conversion behaviour on the ps-timescale in K-PHI. We highlight the importance of dielectric property characterization at THz frequencies as critical for understanding photophysical behaviour at exciton or charge separation time scales, especially in the presence of water and hydrated ions, which may also be beneficial for computation, exploring next generation photocatalysts, electronics or ionotronics.

\"I figured something like this would happen,\" grumbles Joe Davis, as the oil can rattles to a stop. \"This touring stuff never was anything but the sliced salami.\"

Advancements in brain imaging techniques have significantly expanded the size and complexity of real-time neuroimaging and behavioral data. However, identifying patterns, trends and synchronies within these datasets presents a significant computational challenge. Here, we demonstrate an approach that can translate time-varying neuroimaging data into unique audiovisualizations consisting of audible representations of dynamic data merged with simplified, color-coded movies of spatial components and behavioral recordings. Multiple variables can be encoded as different musical instruments, letting the observer differentiate and track multiple dynamic parameters in parallel. This representation enables intuitive assimilation of these datasets for behavioral correlates and spatiotemporal features such as patterns, rhythms and motifs that could be difficult to detect through conventional data interrogation methods. These audiovisual representations provide a novel perception of the organization and patterns of real-time activity in the brain, and offer an intuitive and compelling method for complex data visualization for a wider range of applications.

Learning alters cortical representations and improves perception. Apical tuft dendrites in cortical layer 1, which are unique in their connectivity and biophysical properties, may be a key site of learning-induced plasticity. We used both two-photon and SCAPE microscopy to longitudinally track tuft-wide calcium spikes in apical dendrites of layer 5 pyramidal neurons in barrel cortex as mice learned a tactile behavior. Mice were trained to discriminate two orthogonal directions of whisker stimulation. Reinforcement learning, but not repeated stimulus exposure, enhanced tuft selectivity for both directions equally, even though only one was associated with reward. Selective tufts emerged from initially unresponsive or low-selectivity populations. Animal movement and choice did not account for changes in stimulus selectivity. Enhanced selectivity persisted even after rewards were removed and animals ceased performing the task. We conclude that learning produces long-lasting realignment of apical dendrite tuft responses to behaviorally relevant dimensions of a task.