Does re-opening schools contribute to the spread of SARS-CoV-2?:Evidence from staggered summer breaks in Germany

This paper studies the effect of the end of school summer breaks on SARS-CoV-2 cases in Germany. The staggered timing of summer breaks across federal states allows us to implement an event study design. We base our analysis on official daily counts of confirmed coronavirus infections by age groups across all 401 German counties. We consider an event window of two weeks before and four weeks after the end of summer breaks. We do not find evidence of a positive effect of school re-openings on case numbers. For individuals aged between 5 and 59 years, comprising school-aged children and their parents, our pre- ferred specification indicates that the end of summer breaks had a negative but insignificant effect on the number of new confirmed cases. Our results are not explained by changes in mobility patterns around school re-openings arising from travel returnees. Analyses of Google Trends data suggest that behavioral changes of parents may have contributed to contain larger outbreaks after school re-openings. We conclude that school re-openings in Germany under strict hygiene measures combined with quarantine and containment measures have not increased the number of newly confirmed SARS-CoV-2 infections

MinActionPath: maximum likelihood trajectory for large-scale structural transitions in a coarse-grained locally harmonic energy landscape

The non-linear problem of simulating the structural transition between two known forms of a macromolecule still remains a challenge in structural biology. The problem is usually addressed in an approximate way using ‘morphing’ techniques, which are linear interpolations of either the Cartesian or the internal coordinates between the initial and end states, followed by energy minimization. Here we describe a web tool that implements a new method to calculate the most probable trajectory that is exact for harmonic potentials; as an illustration of the method, the classical Calpha-based Elastic Network Model (ENM) is used both for the initial and the final states but other variants of the ENM are also possible. The Langevin equation under this potential is solved analytically using the Onsager and Machlup action minimization formalism on each side of the transition, thus replacing the original non-linear problem by a pair of linear differential equations joined by a non-linear boundary matching condition. The crossover between the two multidimensional energy curves around each state is found numerically using an iterative approach, producing the most probable trajectory and fully characterizing the transition state and its energy. Jobs calculating such trajectories can be submitted on-line at: http://lorentz.dynstr.pasteur.fr/joel/index.php

AquaSAXS: a web server for computation and fitting of SAXS profiles with non-uniformally hydrated atomic models

Small Angle X-ray Scattering (SAXS) techniques are becoming more and more useful for structural biologists and biochemists, thanks to better access to dedicated synchrotron beamlines, better detectors and the relative easiness of sample preparation. The ability to compute the theoretical SAXS profile of a given structural model, and to compare this profile with the measured scattering intensity, yields crucial structural informations about the macromolecule under study and/or its complexes in solution. An important contribution to the profile, besides the macromolecule itself and its solvent-excluded volume, is the excess density due to the hydration layer. AquaSAXS takes advantage of recently developed methods, such as AquaSol, that give the equilibrium solvent density map around macromolecules, to compute an accurate SAXS/WAXS profile of a given structure and to compare it to the experimental one. Here, we describe the interface architecture and capabilities of the AquaSAXS web server (http://lorentz.dynstr.pasteur.fr/aquasaxs.php)

Does re-opening schools contribute to the spread of SARS-CoV-2?: Evidence from staggered summer breaks in Germany

This paper studies the effect of the end of school summer breaks on SARS-CoV-2 cases in Germany. The staggered timing of summer breaks across federal states allows us to implement an event study design. We base our analysis on official daily counts of confirmed coronavirus infections by age groups across all 401 German counties. We consider an event window of two weeks before and four weeks after the end of summer breaks. We do not find evidence of a positive effect of school re-openings on case numbers. For individuals aged between 5 and 59 years, comprising school-aged children and their parents, our pre- ferred specification indicates that the end of summer breaks had a negative but insignificant effect on the number of new confirmed cases. Our results are not explained by changes in mobility patterns around school re-openings arising from travel returnees. Analyses of Google Trends data suggest that behavioral changes of parents may have contributed to contain larger outbreaks after school re-openings. We conclude that school re-openings in Germany under strict hygiene measures combined with quarantine and containment measures have not increased the number of newly confirmed SARS-CoV-2 infections