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In the past years, we have undertaken an extensive investigation of LMC and SMC star clusters based on HST data. We present photometry and astrometry of stars in 101 fields observed with the WFC/ACS, UVIS/WFC3 and NIR/WFC3 cameras. These fields comprise 113 star clusters. We provide differential-reddening maps and illustrate various scientific outcomes that arise from the early inspection of the photometric catalogs. In particular, we provide new insights on the extended main-sequence turn-off (eMSTO) phenomenon: i) We detected eMSTOs in two clusters, KMHK361 and NGC265, which had no previous evidence of multiple populations. This finding corroborates the conclusion that the eMSTO is a widespread phenomenon among clusters younger than ~2 Gyr. ii) The homogeneous color-magnitude diagrams (CMDs) of 19 LMC clusters reveal that the distribution of stars along the eMSTO depends on cluster age. iii) We discovered a new feature along the eMSTO of NGC1783, which consists of a distinct group of stars going on the red side of the eMSTO in CMDs composed of ultraviolet filters. Furthermore, we derived the proper motions of stars in the fields of view of clusters with multi-epoch images. Proper motions allowed us to separate the bulk of bright field stars from cluster members and investigate the internal kinematics of stellar populations in various LMC and SMC fields. As an example, we analyze the field around NGC346 to disentangle the motions of its stellar populations, including NGC364 and BS90, young and pre-MS stars in the star-forming region associated with NGC346, and young and old field stellar populations of the SMC. Based on these results and the fields around five additional clusters, we find that young SMC stars exhibit elongated proper-motion distributions that point toward the LMC, thus bringing new evidence for a kinematic connection between the LMC and SMC., Comment: 37 pages, 27 figures, accepted for publication in Astronomy & Astrophysics

The presence of differential reddening in the direction of Galactic globular clusters (GCs) has proven to be a serious limitation in the traditional colour-magnitude diagram (CMD) analysis. Here, we estimate local reddening variations in the direction of 56 Galactic GCs. To do that, we use the public catalogs derived as part of the Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters, which include photometry in the F275W, F336W, F438W, F606W, and F814W filters. We correct photometry for differential reddening finding that for 21 out of 56 GCs the adopted correction procedure significantly improves the CMDs. Moreover, we measure the reddening law in the direction of these clusters finding that $R_{V}$ exhibits a high level of variability within the Galaxy, ranging from $\sim2.0$ to $\sim4.0$. The updated values of $R_{V}$ have been used to improve the determination of local reddening variations and derive high-resolution reddening maps in the direction of the 21 highly-reddened targets within our sample. To compare the results of the different clusters, we compute the 68$^{\rm th}$ percentile of the differential-reddening distribution, $\sigma_{\Delta A_{\rm F814W}}$. This quantity ranges from 0.003 mag to 0.030 mag and exhibits a significant anti-correlation with the absolute module of the Galactic latitude and a strong correlation with the average reddening in the direction of each cluster. Therefore, highly-reddened GCs located in the proximity of the Galactic plane typically show higher differential-reddening variations across their field of view., Comment: 14 pages, 14 figures, accepted for pubblication in MNRAS. The photometric catalogs corrected for differential reddening are publicly available at this website: http://progetti.dfa.unipd.it/GALFOR/

We use images collected with the near-infrared camera (NIRCam) on board the James Webb Space Telescope and with the Hubble Space Telescope (HST) to investigate multiple populations at the bottom of the main sequence (MS) of 47 Tucanae. The F115W vs. F115W-F322W2 CMD from NIRCam shows that, below the knee, the MS stars span a wide color range, where the majority of M-dwarfs exhibit blue colors, and a tail of stars are distributed toward the red. A similar pattern is observed from the F160W vs. F110W-F160W CMD from HST, and multiple populations of M-dwarfs are also visible in the optical F606W vs. F606W-F814W CMD. The NIRCam CMD shows a narrow sequence of faint MS stars with masses smaller than 0.1 solar masses. We introduce a chromosome map of M-dwarfs that reveals an extended first population and three main groups of second-population stars. By combining isochrones and synthetic spectra with appropriate chemical composition, we simulate colors and magnitudes of different stellar populations in the NIRCam filters (at metallicities [Fe/H]=-1.5 and [Fe/H]=-0.75) and identify the photometric bands that provide the most efficient diagrams to investigate the multiple populations in globular clusters. Models are compared with the observed CMDs of 47 Tucanae to constrain M-dwarfs' chemical composition. Our analysis suggests that the oxygen range needed to reproduce the colors of first- and second-population M-dwarfs is similar to that inferred from spectroscopy of red giants, constraining the proposal that the chemical variations are due to mass transfer phenomena in proto-clusters., Comment: 21 pages, 17 figures, accepted for publication in MNRAS

Background: Mycoplasmas (Mycoplasma spp. and Ureaplasma spp.) are sexually transmitted organisms found primarily in the human urogenital microbiota. These microorganisms are frequently associated with some diseases including non-gonococcal urethritis, vaginosis, pregnancy complications, prenatal infections, systemic infections and infertility. Objectives: The current studyaimedto evaluate the prevalence of Mycoplasma hominisandUreaplasmaspp. in routinegynecological care. Patients and Methods: A cross sectional study with simple random sampling was designed. A total of 6,810 patients with the age range of 11 to 80 years were evaluated, during a six-month period from January 2015 to June 2015 in Sao Paulo, Brazil. DNAs were extracted from cytological samples (ThinPrep™) to detect microorganisms by real-time polymerase chain reaction (qPCR). Results: The high prevalence of M. hominis (n = 79), Ureaplasma spp. (n = 2,026) and the co-colonization of both (n = 199) with P < 0.0001 in the samples were verified, mainly in sexually active aged females. The results also indicated a negative and significant correlation between co-colonization of Ureaplasma spp. and M. hominis, Ureaplasma spp., and age. Conclusions: In conclusion, the data showed that high rate of females harbor these microorganisms in the genital microbiota. This finding suggests the importance of routine gynecological tests, mainly in pregnant females, during the second and third trimesters, and in asymptomatic females under infertility clinical investigation. Furthermore, the application of molecular methods is suggested; since they provide a fast and accurate diagnosis of these microorganisms, but sensitivity of the tests should be considered in the clinical relevant concentration of microorganisms in the genital microbiota