The incidence of diarrhea due to six categories of diarrheogenic Escherichia coli was determined in two pediatric cohorts in a low socioeconomic level community in Santiago, Chile, with access to chlorinated water. An age cross-sectional cohort of 340 children aged birth to 47 months was assembled. A newborn cohort was assembled by enrolling 10-12 newborns monthly for 12 months. Episodes of diarrhea were detected by twice weekly household visits. E. coli from stool cultures of cases and matched controls were hybridized with DNA probes specific for enterotoxigenic, enteroinvasive, enteropathogenic, enterohemorrhagic, enteroaggregative, and diffuse adherence E. coli. Overall, the incidence of diarrhea was low (2.1 episodes/infant/year). Nevertheless, a putative E. coli enteropathogen was found in a large proportion of diarrheal episodes, particularly during the summer. In both cohorts, enterotoxigenic E. coli were important pathogens. Enteropathogenic E. coli were incriminated during the first year of life in the newborn cohort, where they were found significantly more often in cases (p = 0.021) than in controls; beyond this age, isolation rates were similar. In contrast, the relative risk of isolation of diffuse adherence E. coli increased with age in the age cross-sectional cohort, where, overall, the difference in rate of isolation between cases and controls was significant (p = 0.0024). Enteroinvasive and enterohemorrhagic E. coli were isolated infrequently. Enteroaggregative E. coli were encountered equally in cases and controls. Facile transmission of E. coli enteropathogens is occurring in this community despite the availability of potable water.

We present Reverberation Mapping (RM) results for 17 high-redshift, high-luminosity quasars with good quality R-band and emission line light curves. We are able to measure statistically significant lags for Lyα (11 objects), SiIV (5 objects), CIV (11 objects), and CIII] (2 objects). Using our results and previous lag determinations taken from the literature, we present an updated CIV radiusluminosity relation and provide for the first time radius-luminosity relations for Lyα, SiIV and CIII]. While in all cases the slope of the correlations are statistically significant, the zero points are poorly constrained because of the lack of data at the low luminosity end. We find that the emissivity weighted distance from the central source of the Lyα, SiIV and CIII] line emitting regions are all similar, which corresponds to about half that of the Hβ region. We also find that 3/17 of our sources show an unexpected behavior in some emission lines, two in the Lyα light curve and one in the SiIV light curve, in that they do not seem to follow the variability of the UV continuum. Finally, we compute RM black hole masses for those quasars with highly significant lag measurements and compare them with CIV single-epoch (SE) mass determinations. We find that the RM-based black hole mass determinations seem smaller than those found using SE calibrations.

A cohort of 113 women and their newborns from the coastal area of El Salvador were studied longitudinally to estimate malaria incidence and indirect fluorescent antibody (IFA) response to malaria infection. The district in which the study was conducted had an estimated annual parasite index of 600/1,000 inhabitants, and all malaria infections were treated immediately with a 4-aminoquinoline. In the third trimester of pregnancy, the IFA response to Plasmodium falciparum was significantly depressed. As a result of antimalarial therapy and depressed immune responsiveness, 49% (P. vivax) and 53% (P. falciparum) of the pregnant subjects had a malaria IFA titer less than 1:20 at the time of delivery. Malaria IFA crossed the placenta to the fetus with a step-down of approximately a 4-fold dilution, except for the step-up noted in the P. falciparum titer for 17 of 116 newborns. Due to the overall low prevalence and intensity of maternal IFA, a titer of at least 1:20 was passed to only 23% (P. vivax) and 45% (P. falciparum) of newborns. Passively-acquired malaria IFA degraded with a half-life estimated between 43 and 52 days. During follow-up of infants to 6 months of age, no protection from malaria resulting from passively-acquired antibody could be demonstrated. Because of the limited transplacental immunization of these newborns with antimalarial antibody, it appears that passive immunity can exert little effect on the incidence of infant malaria in coastal El Salvador.

The third observing run by LVC has brought the discovery of many compact binary coalescences. Following the detection of the first binary neutron star merger in this run (LIGO/Virgo S190425z), we performed a dedicated follow-up campaign with the Zwicky Transient Facility (ZTF) and Palomar Gattini-IR telescopes. The initial skymap of this single-detector gravitational wave (GW) trigger spanned most of the sky observable from Palomar Observatory. Covering 8000 deg 2 of the initial skymap over the next two nights, corresponding to 46% integrated probability, ZTF system achieved a depth of ≈21 m AB in g-and r-bands. Palomar Gattini-IR covered 2200 square degrees in J-band to a depth of 15.5 mag, including 32% integrated probability based on the initial skymap. The revised skymap issued the following day reduced these numbers to 21% for the ZTF and 19% for Palomar Gattini-IR. We narrowed 338,646 ZTF transient "alerts" over the first two nights of observations to 15 candidate counterparts. Two candidates, ZTF19aarykkb and ZTF19aarzaod, were particularly compelling given that their location, distance, and age were consistent with the GW event, and their early optical light curves were photometrically consistent with that of kilonovae. These two candidates were spectroscopically classified as young core-collapse supernovae. The remaining candidates were ruled out as supernovae. Palomar Gattini-IR did not identify any viable candidates with multiple detections only after merger time. We demonstrate that even with single-detector GW events localized to thousands of square degrees, systematic kilonova discovery is feasible.

The developmental impact of opioid use during pregnancy is a subject of ongoing debate. Short-term neonatal outcomes, such as lower birth weight and neonatal abstinence syndrome, are the most well-recognized outcomes. However, knowledge gaps exist regarding longer-term neurocognitive and mental health outcomes. In this article, we summarize an expert panel discussion that was held in April 2018 by the Substance Abuse and Mental Health Services Administration and attended by national experts in the field of perinatal opioid exposure and its impact on child development. Despite the challenges with research in this area, there is emerging literature revealing an association between neonates exposed to opioids in utero and longer-term adverse neurocognitive, behavioral, and developmental outcomes. Although adverse sequalae may not be apparent in the neonatal period, they may become more salient as children develop and reach preschool and school age. Multiple variables (genetic, environmental, and biological) result in a highly complex picture. The next steps and strategies to support families impacted by opioid use disorder are explored. Model programs are also considered, including integrated care for the child and mother, parenting supports, and augmentations to home visiting.