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The technique of mutual approximations accurately gives the central instant at the maximum apparent approximation of two moving natural satellites in the sky plane. This can be used in ephemeris fitting to infer the relative positions between satellites with high precision. Only the mutual phenomena -- occultations and eclipses -- may achieve better results. However, mutual phenomena only occur every six years in the case of Jupiter. Mutual approximations do not have this restriction and can be observed at any time along the year as long as the satellites are visible. In this work, we present 104 central instants determined from the observations of 66 mutual approximations between the Galilean moons carried out at different sites in Brazil and France during the period 2016--2018. For 28 events we have at least two independent observations. All telescopes were equipped with a narrow-band filter centred at 889 nm with a width of 15 nm to eliminate the scattered light from Jupiter. The telescope apertures ranged between 25--120 cm. For comparison, the precision of the positions obtained with classical CCD astrometry is about 100 mas, for mutual phenomena it can achieve 10 mas or less and the average internal precision obtained with mutual approximations was 11.3 mas. This new kind of simple, yet accurate observations can significantly improve the orbits and ephemeris of Galilean satellites and thus be very useful for the planning of future space missions aiming at the Jovian system., Comment: 12 pages, 7 figures

TOBACCO USE is among the leading preventable causes of death worldwide,1 and is a major contributor to respiratory diseases, including tuberculosis (TB).2 Smoking reduces normal mucociliary clearance of tracheobronchial secretions and impairs alveolar macrophage function against Mycobacterium tuberculosis.3 Culture conversion to negative after the first 2 months of treatment is a widely used measure of bacteriologic response to therapy in anti-tuberculosis treatment trials, and is associated with long-term cure.4 Delayed sputum conversion prolongs the time during which patients are infectious and capable of transmitting TB to others in their community. Several studies have examined the impact of smoking on sputum smear and culture conversion and outcomes of TB treatment.2 Smoking did not affect smear conversion in a study from Kuwait,5 whereas smoking and bilateral cavitary disease increased the risk of culture positivity two fold after the first 2 months of treatment in a cohort of non-human immunodeficiency virus (HIV) infected patients with drug-susceptible TB in Spain.6 Batista et al. recently reported that smoking was associated with a 2.5-fold increased risk of relapse after treatment in 754 patients in Brazil.7 However, most earlier studies did not control for confounding by other factors associated with delayed response to treatment, such as non-adherence to treatment, alcohol use and cavitary disease.8 To further examine the impact of smoking and other factors on bacillary clearance and response to anti-tuberculosis treatment, we analyzed sputum culture status during the first 2 months of treatment in adults with non-cavitary pulmonary TB participating in a TB treatment trial.