Determining the halo mass scale where galaxies lose their gas

A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well characterized clusters and groups at $0.410.4$) of these old galaxies with weak [OII] emission. We use line ratios and compare to studies of local early type galaxies to conclude that this gas is likely excited by post-AGB stars and hence represents a diffuse gas component in the galaxies. For cluster and group galaxies the fraction with EW([OII])$>5$\AA\ is $f_{[OII]}=0.08^{+0.03}_{-0.02}$ and $f_{[OII]}=0.06^{+0.07}_{-0.04}$ respectively. For field galaxies we find $f_{[OII]}=0.27^{+0.07}_{-0.06}$, representing a 2.8$\sigma$ difference between the [OII] fractions for old galaxies between the different environments. We conclude that a population of old galaxies in all environments has ionized gas that likely stems from stellar mass loss. In the field galaxies also experience gas accretion from the cosmic web and in groups and clusters these galaxies have had their gas accretion shut off by their environment. Additionally, galaxies with emission preferentially avoid the virialized region of the cluster in position-velocity space. We discuss the implications of our results, among which is that gas accretion shutoff is likely effective at group halo masses (log~${\cal M}/$\msol$>12.8$) and that there are likely multiple gas removal processes happening in dense environments

Perfusion Index and Pulse Oximetry Screening for Congenital Heart Defects

Objective To evaluate the efficacy of combined pulse oximetry (POX) and perfusion index (PI) neonatal screening for severe congenital heart defects (sCHD) and assess different impacts of screening in tertiary and nontertiary hospitals. Study design A multicenter, prospective study in 10 tertiary and 6 nontertiary maternity hospitals. A total of 42\u2009169 asymptomatic newborns from among 50\u2009244 neonates were screened; exclusion criteria were antenatal sCHD diagnosis, postnatal clinically suspected sCHD, and neonatal intensive care unit admission. Eligible infants underwent pre- and postductal POX and PI screening after routine discharge examination. Targeted sCHD were anatomically defined. Positivity was defined as postductal oxygen saturation (SpO2) 6495%, prepostductal SpO2gradient >3%, or PI <0.90. Confirmed positive cases underwent echocardiography for definitive diagnosis. Missed cases were identified by consulting clinical registries at 6 regional pediatric heart centers. Main outcomes were incidence of unexpected sCHD; proportion of undetected sCHD after discharge in tertiary and nontertiary hospitals; and specificity, sensitivity, positive predictive value, and negative predictive value of combined screening. Results One hundred forty-two sCHD were detected prenatally. Prevalence of unexpected sCHD was 1 in 1115 live births, similar in tertiary and nontertiary hospitals. Screening identified 3 sCHD (low SpO2, 2; coarctation for low PI, 1). Four cases were missed. In tertiary hospitals, 95% of unsuspected sCHDs were identified clinically, whereas only 28% in nontertiary units; in nontertiary units PI-POX screening increased the detection rate to 71%. Conclusions PI-POX predischarge screening provided benefits in nontertiary units, where clinical recognition rate was low. PI can help identify coarctation cases missed by POX but requires further evaluation in populations with higher rates of missed cases

Congenital syphilis in Italy: a multicentre study

OBJECTIVE: To study the prevalence of congenital syphilis and its risk factors in Italy. STUDY DESIGN: Prospective study from 1 July 2006 to 30 June 2007. Data on mother-child pairs were collected for every syphilis seropositive mother. RESULTS: Maternal syphilis seroprevalence at delivery was 0.17%. 207 infants were born to 203 syphilis seropositive mothers. In 25 newborns it was possible to diagnose congenital syphilis (20/100,000 live births). Maternal risk factors included age <20 years, no antenatal care and no adequate treatment. The infected babies were more often preterm or weighed <2000 g at birth. DISCUSSION: Many syphilis seropositive mothers were foreign born but the risk of an infected newborn was not higher in foreign-born than in Italian seropositive women. The significant factors were lack of antenatal screening and inadequate maternal treatment. CONCLUSION: Syphilis is a re-emerging infection in Italy. Prevention strategies should include antenatal serological tests for all pregnant women and treatment for infected mothers