School Closures and Respiratory Infections Transmission and Mortality: Evidence from School Holidays in Poland.

This study examines the impact of temporary school closures on influenza transmission and respiratory mortality, leveraging a natural experiment from winter break timings in Polish schools. Using causal inference methods on 12 years of ILI (Influenza-Like Illness) data and two decades of respiratory death records, the analysis shows significant reductions in ILI incidence within four weeks post-closures in an average season: 75% among school-aged children, 55% in adults, 26% in pre-school children, and 31% in the elderly, compared to pre-vacation averages. Notably, a 7% decrease in respiratory mortality was observed among the elderly, highlighting school closures as an effective public health intervention for reducing influenza spread and mortality among high-risk groups.

High-Statistics Measurement of Collins and Sivers Asymmetries for Transversely Polarized Deuterons.

New results are presented on a high-statistics measurement of Collins and Sivers asymmetries of charged hadrons produced in deep inelastic scattering of muons on a transversely polarized ^{6}LiD target. The data were taken in 2022 with the COMPASS spectrometer using the 160 GeV muon beam at CERN, statistically balancing the existing data on transversely polarized proton targets. The first results from about two-thirds of the new data have total uncertainties smaller by up to a factor of three compared to the previous deuteron measurements.

Final COMPASS Results on the Transverse-Spin-Dependent Azimuthal Asymmetries in the Pion-Induced Drell-Yan Process.

The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190  GeV/c π^{-} beam impinging on a transversely polarized ammonia target. Combining the data of both years, we present final results on the amplitudes of five azimuthal modulations, which correspond to transverse-spin-dependent azimuthal asymmetries (TSAs) in the dimuon production cross section. Three of them probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs).

Opening of hotels and ski facilities: Impact on mobility, spending, and Covid-19 outcomes.

This paper investigates how reopening hotels and ski facilities in Poland impacted tourism spending, mobility, and COVID-19 outcomes. We used administrative data from a government program that subsidizes travel to show that the policy increased the consumption of tourism services in ski resorts. By leveraging geolocation data from Facebook, we showed that ski resorts experienced a significant influx of tourists, increasing the number of local users by up to 50%.