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Background Vaccines are an important means to overcome the SARS-CoV-2 pandemic. They induce specific anti-body and T-cell responses but it remains open how well vaccine-induced immunity is preserved over time following homologous and heterologous immunization regimens. Here, we compared the dynamics of humoral and cellular immune responses up to 180 days after homologous or heterologous vaccination with either ChAdOx1-nCoV-19 (ChAd) or BNT162b2 (BNT) or both.Methods Various tests were used to determine the humoral and cellular immune response. To quantify the antibody levels, we used the surrogate neutralization (sVNT) assay from YHLO, which we augmented with pseudo-and real virus neutralization tests (pVNT and rVNT). Antibody avidity was measured by a modified ELISA. To determine cel-lular reactivity, we used an IFN-g Elispot, IFN-g/IL Flurospot, and intracellular cytokine staining.Findings Antibody responses significantly waned after vaccination, irrespective of the regimen. The capacity to neu-tralize SARS-CoV-2 -including variants of concern such as Delta or Omicron -was superior after heterologous compared to homologous BNT vaccination, both of which resulted in longer-lasting humoral immunity than homol-ogous ChAd immunization. All vaccination regimens induced stable, polyfunctional T-cell responses. Interpretation These findings demonstrate that heterologous vaccination with ChAd and BNT is a potent alternative to induce humoral and cellular immune protection in comparison to the homologous vaccination regimens.Copyright (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Methane bubbling up from subarctic lakes is one of the contributing factors to climate change. The annual freezing of these lakes influences the methane release, especially the grounding of the ice cover strongly reduces methane emissions. Using Google Earth Engine (GEE) as the pri- mary data source and geospatial computing platform, we investigated and compared grounded ice formation in Barrow, Alaska (USA) and Kytalyk, Yakutia (Russia) from 2017 to 2020. Using Sentinel-1 SAR data, we took into account all four polarisations (HH, VV, HV and VH). Based on the VV-polarised backscatter time series (12-days revisit intervals), the approximate dates for the annual ice maxima were determined for both study sites. The backscatter frequency distributions of masked lake ice surfaces were then used to set a global threshold value for each polarisation. We found that cross-pol (VH, HV) images individually are not well suited for grounded ice detection, as their thresholds need to be set too close to the Noise Equivalence Sigma Zero (NESZ) noise floor to produce plausible results. The co-polarised classifications on the other hand, produced results at both study sites that were in agreement with Joint Research Center (JRC) ERA5 climate reanal- ysis weather data. From 2017 to 2019, both study sites showed a steady increase in grounded ice of around +3% in Barrow and +6% in Kytalyk. In 2020, the grounded ice percentage in Barrow strongly rose (+9%) from 2019, while in Kytalyk, less grounded ice was formed (-3%). The de- tected grounded ice fractions were much higher in Barrow (between 32 and 48%) than in Kytalyk (5 - 14%), indicating deeper lakes in Kytalyk. The co-pol map products were very similar to each other, with overall consistencies always staying above 90% in all tests conducted. However, VV- based classifications always detected more grounded ice (between +0.38 and +4.33%) compared to the HH-classifications. We found that these deviations are positively correlated with

Lawns are considered monocultures and lesser contributors to sustainability than diverse nature but are still a dominating green area feature and an important cultural phenomenon in cities. Lawns have esthetical values, provide playground, are potential habitat for species, contribute to carbon sequestration and water infiltration, but also increase pesticides, fertilization, aremonocultures and costly to manage at the same time. To evaluate the potential impact of lawns, whether positive or negative, it is of interest to estimate the total lawn cover in cities and its change over time. This is not a straightforward process, e.g., because many lawns are small and covered by trees. In this study we review the existing literature of lawn cover in cities and the different methodologies used for cover estimation. We found both pros and cons with NDVI and LiDAR data as well as manually interpreted aerial photos. The total cover of lawns in three case study cities was estimated to 22.5%. By extrapolating these percentages to all Swedish cities lawn cover was estimated to 2589 km(2) (0.6% of the terrestrial surface). The approximated total municipal management cost of lawns in all Swedish cities was 910,000,000 USD/year. During 50 years lawn area almost doubled in relative cover and 56% of them were continuously managed. Since lawns constitute large parts of the urban greenery and are costly to manage it is highly relevant to consider their social, ecological and cultural value compared to alternatives, e.g., meadows with less intensive management.