How to Determine When SARS-CoV-2 Antibody Testing Is or Is Not Useful for Population Screening: A Tutorial

Extensive testing lies at the heart of any strategy to effectively combat the SARS-COV-2 pandemic. In recent months, the use of enzyme-linked immunosorbent assay–based antibody tests has gained a lot of attention. These tests can potentially be used to assess SARS-COV-2 immunity status in individuals (e.g., essential health care personnel). They can also be used as a screening tool to identify people that had COVID-19 asymptomatically, thus getting a better estimate of the true spread of the disease, gain important insights on disease severity, and to better evaluate the effectiveness of policy measures implemented to combat the pandemic. But the usefulness of these tests depends not only on the quality of the test but also, critically, on how far disease has already spread in the population. For example, when only very few people in a population are infected, a positive test result has a high chance of being a false positive. As a consequence, the spread of the disease in a population as well as individuals’ immunity status may be systematically misinterpreted. SARS-COV-2 infection rates vary greatly across both time and space. In many places, the infection rates are very low but can quickly skyrocket when the virus spreads unchecked. Here, we present two tools, natural frequency trees and positive and negative predictive value graphs, that allow one to assess the usefulness of antibody testing for a specific context at a glance. These tools should be used to support individual doctor-patient consultation for assessing individual immunity status as well as to inform policy discussions on testing initiatives.Peer Reviewe

Smart Electric Vehicle Charging considering Discounts for Customer Flexibility

The expansion of large-scale charging infrastructure is crucial to cope with growing shares of electric vehicles. However, operators often struggle with profitable operation due to volatile occupancy and high costs for peaks in charging demand. Using information and communication technology may enable smart charging and thereby profitable operation by addressing the challenge of costly peak demand but requires customer flexibility to shift and manage charging processes. Therefore, operators must offer discounts on charging prices for customers to provide flexibility, which in turn mark an additional cost. Here we provide a model to analyze whether the costs to allocate flexibility exceed cost savings through smart charging. The model is evaluated in a case study of a large-scale charging park with real-world data on highway traffic and charging station usage. The results indicate that smart charging can provide net benefits even if operators are required to offer discounts for charging flexibility

Lasting Effects of Soil Compaction on Soil Water Regime Confirmed by Geoelectrical Monitoring

Despite its importance for hydrological and ecological soil functioning, characterizing, and quantifying soil structure in the field remains a challenge. Traditional characterization of soil structure often relies on point measurements, more recently, we advanced the use of minimally invasive geophysical methods that operate at plot-field scales and provide information under natural conditions. In this study, we expand the application using geoelectrical and time-domain reflectometry (TDR) monitoring of soil water dynamics to infer impacts of compaction on soil structure and function. We developed a modeling scheme combining a new pedophysical model of soil electrical conductivity and a soil-structure-informed one-dimensional water flow and heat-transfer model. The model was used to interpret Direct Current (DC)-resistivity and TDR monitoring data in compacted soils at the Soil Structure Observatory (SSO) located in the vicinity of Zürich, Switzerland. We find that (1) soil compaction leads to a persistent decrease in soil electrical resistivity and (2) that compacted soils are typically drier than non-compacted soils during long drying events. The main decrease in electrical resistivity is attributed to decreasing macroporosity and increasing connectivity of soil aggregates due to compaction. Higher water losses in compacted soils are explained in terms of enhanced evaporation. Our work advances characterization of soil structure at the field scale with electrical methods by offering a physically based explanation of the impact of soil compaction on electrical properties and by interpreting DC-resistivity data in terms of soil water dynamics

Lasting Effects of Soil Compaction on Soil Water Regime Confirmed by Geoelectrical Monitoring

Despite its importance for hydrological and ecological soil functioning, characterizing, and quantifying soil structure in the field remains a challenge. Traditional characterization of soil structure often relies on point measurements, more recently, we advanced the use of minimally invasive geophysical methods that operate at plot-field scales and provide information under natural conditions. In this study, we expand the application using geoelectrical and time-domain reflectometry (TDR) monitoring of soil water dynamics to infer impacts of compaction on soil structure and function. We developed a modeling scheme combining a new pedophysical model of soil electrical conductivity and a soil-structure-informed one-dimensional water flow and heat-transfer model. The model was used to interpret Direct Current (DC)-resistivity and TDR monitoring data in compacted soils at the Soil Structure Observatory (SSO) located in the vicinity of Zurich, Switzerland. We find that (1) soil compaction leads to a persistent decrease in soil electrical resistivity and (2) that compacted soils are typically drier than non-compacted soils during long drying events. The main decrease in electrical resistivity is attributed to decreasing macroporosity and increasing connectivity of soil aggregates due to compaction. Higher water losses in compacted soils are explained in terms of enhanced evaporation. Our work advances characterization of soil structure at the field scale with electrical methods by offering a physically based explanation of the impact of soil compaction on electrical properties and by interpreting DC-resistivity data in terms of soil water dynamics

Evolutionary history of the recruitment of conserved developmental genes in association to the formation and diversification of a novel trait.

BACKGROUND: The origin and modification of novel traits are important aspects of biological diversification. Studies combining concepts and approaches of developmental genetics and evolutionary biology have uncovered many examples of the recruitment, or co-option, of genes conserved across lineages for the formation of novel, lineage-restricted traits. However, little is known about the evolutionary history of the recruitment of those genes, and of the relationship between them -for example, whether the co-option involves whole or parts of existing networks, or whether it occurs by redeployment of individual genes with de novo rewiring. We use a model novel trait, color pattern elements on butterfly wings called eyespots, to explore these questions. Eyespots have greatly diversified under natural and sexual selection, and their formation involves genetic circuitries shared across insects. RESULTS: We investigated the evolutionary history of the recruitment and co-recruitment of four conserved transcription regulators to the larval wing disc region where circular pattern elements develop. The co-localization of Antennapedia, Notch, Distal-less, and Spalt with presumptive (eye)spot organizers was examined in 13 butterfly species, providing the largest comparative dataset available for the system. We found variation between families, between subfamilies, and between tribes. Phylogenetic reconstructions by parsimony and maximum likelihood methods revealed an unambiguous evolutionary history only for Antennapedia, with a resolved single origin of eyespot-associated expression, and many homoplastic events for Notch, Distal-less, and Spalt. The flexibility in the (co-)recruitment of the targeted genes includes cases where different gene combinations are associated with morphologically similar eyespots, as well as cases where identical protein combinations are associated with very different phenotypes. CONCLUSIONS: The evolutionary history of gene (co-)recruitment is consistent with both divergence from a recruited putative ancestral network, and with independent co-option of individual genes. The diversity in the combinations of genes expressed in association with eyespot formation does not parallel diversity in characteristics of the adult phenotype. We discuss these results in the context of inferring homology. Our study underscores the importance of widening the representation of phylogenetic, morphological, and genetic diversity in order to establish general principles about the mechanisms behind the evolution of novel traits.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Long-Term Soil Structure Observatory for Monitoring Post-Compaction Evolution of Soil Structure

The projected intensification of agriculture to meet food targets of a rapidly growing world population are likely to accentuate already acute problems of soil compaction and deteriorating soil structure in many regions of the world. The key role of soil structure for soil functions, the sensitivity of soil structure to agronomic management practices, and the lack of reliable observations and metrics for soil structure recovery rates after compaction motivated the establishment of a long-term Soil Structure Observatory (SSO) at the Agroscope research institute in Zürich, Switzerland. The primary objective of the SSO is to provide long-term observation data on soil structure evolution after disturbance by compaction, enabling quantification of compaction recovery rates and times. The SSO was designed to provide information on recovery of compacted soil under different post-compaction soil management regimes, including natural recovery of bare and vegetated soil as well as recovery with and without soil tillage. This study focused on the design of the SSO and the characterization of the pre- and post-compaction state of the field. We deployed a monitoring network for continuous observation of soil state variables related to hydrologic and biophysical functions (soil water content, matric potential, temperature, soil air O2 and CO2 concentrations, O2 diffusion rates, and redox states) as well as periodic sampling and in situ measurements of infiltration, mechanical impedance, soil porosity, gas and water transport properties, crop yields, earthworm populations, and plot-scale geophysical measurements. Besides enabling quantification of recovery rates of compacted soil, we expect that data provided by the SSO will help improve our general understanding of soil structure dynamics

The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and its Implications for Structure Growth

We present new measurements of cosmic microwave background (CMB) lensing over $9400$ sq. deg. of the sky. These lensing measurements are derived from the Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) CMB dataset, which consists of five seasons of ACT CMB temperature and polarization observations. We determine the amplitude of the CMB lensing power spectrum at $2.3\%$ precision ($43\sigma$ significance) using a novel pipeline that minimizes sensitivity to foregrounds and to noise properties. To ensure our results are robust, we analyze an extensive set of null tests, consistency tests, and systematic error estimates and employ a blinded analysis framework. The baseline spectrum is well fit by a lensing amplitude of $A_{\mathrm{lens}}=1.013\pm0.023$ relative to the Planck 2018 CMB power spectra best-fit $\Lambda$CDM model and $A_{\mathrm{lens}}=1.005\pm0.023$ relative to the $\text{ACT DR4} + \text{WMAP}$ best-fit model. From our lensing power spectrum measurement, we derive constraints on the parameter combination $S^{\mathrm{CMBL}}_8 \equiv \sigma_8 \left({\Omega_m}/{0.3}\right)^{0.25}$ of $S^{\mathrm{CMBL}}_8= 0.818\pm0.022$ from ACT DR6 CMB lensing alone and $S^{\mathrm{CMBL}}_8= 0.813\pm0.018$ when combining ACT DR6 and Planck NPIPE CMB lensing power spectra. These results are in excellent agreement with $\Lambda$CDM model constraints from Planck or $\text{ACT DR4} + \text{WMAP}$ CMB power spectrum measurements. Our lensing measurements from redshifts $z\sim0.5$--$5$ are thus fully consistent with $\Lambda$CDM structure growth predictions based on CMB anisotropies probing primarily $z\sim1100$. We find no evidence for a suppression of the amplitude of cosmic structure at low redshiftsComment: 45+21 pages, 50 figures. Prepared for submission to ApJ. Also see companion papers Madhavacheril et al and MacCrann et a