We examine the contemporaneous causal relationship between outdoor air pollution levels and student cognitive performance in Brazil’s nationwide university entrance examinations. Our analysis relies upon a unique previously unexplored student-level data set allowing us to effect of particulate matter (PM10) on students’ scores. In our main specification we construct individual-level panel for 2...

We investigate classes of SQL queries which are syntactically correct, but certainly not intended, no matter for which task the query was written. For instance, queries that are contradictory, i.e. always return the empty set, are quite often written in exams of database courses. Current database management systems, e.g. Oracle, execute such queries without any warning. In this paper, we give s...

With the continuous development of society and improvement people's living standards, high quality life has become theme life, music is an important part life. In 2021, General Office State Council China issued "Opinions on Further Reducing Burden Classwork Off-Campus Training Students in Compulsory Education" (the "Double Reduction" policy). The "double reduction" policy explicitly requires th...

Asymptomatic/mildly symptomatic coronavirus disease 2019 (COVID-19) patients produce a considerable amount of virus and transmit severe acute respiratory syndrome 2 (SARS-CoV-2) through close contact. Preventing in-hospital transmission SARS-CoV-2 is challenging, since symptom-based screening protocols may miss asymptomatic/mildly patients. In particular, dental healthcare workers (HCWs) are at...